JP2017209842A - Mold for molding tubular hollow body, method for molding tubular hollow body, and tubular hollow body - Google Patents

Abstract

An object of the present invention is to reduce the number of steps for forming a tubular hollow body. A tubular hollow body molding die 10 has a shape of an outer peripheral surface 4 of a tubular hollow body 1, a main cavity 11 into which resin is injected, and one end of the main cavity 11. A pressurizing port 12 into which a pressurized fluid is press-fitted, a discharge port 14 formed at the other end of the main cavity 11 for discharging the resin from the main cavity 11, and a floating provided detachably on the pressurization port 12. A core 16 and a cylindrical stopper 17 extending from the discharge port 14 toward the pressure port 12 side along the axis L11 of the main cavity 11 are provided. When the floating core 16 moves through the main cavity 11 by pressurizing the pressurized fluid from the pressurized port 12, the floating core 16 is pressed against the inner peripheral surface 17 a of the stopper 17. [Selection] Figure 2

Description

  The present invention relates to a tubular hollow body molding die, a tubular hollow body molding method, and a tubular hollow body.

  The tubular hollow body made of resin is used for various parts such as a water pipe, an oil cooling pipe, and an air duct, and is formed into various bent shapes. As one method for producing such a tubular hollow body, there is fluid assist molding described in Patent Documents 1 and 2. In fluid-assisted molding, a molding is provided that includes a main cavity having a pressurization port with a floating core provided at one end and a discharge port formed at the other end, and a subcavity communicated with the discharge port of the main cavity. Prepare a mold. Then, after the resin is injected into the main cavity, the floating core is moved by press-fitting a pressurized fluid from the pressure port, and the resin and the floating core in the main cavity are discharged from the discharge port to the sub-cavity. Thereby, the internal peripheral surface of a tubular hollow body is shape | molded. Thereafter, a resin molded product is taken out from the main cavity and the subcavity, and the portion discharged into the subcavity is cut and removed from the molded product, whereby a tubular hollow body is obtained.

Japanese Patent No. 5038119 JP 09-123212 A

  In the fluid assist molding described in Patent Literatures 1 and 2, the molded product taken out from the molding die is in a state where the resin remaining in the main cavity and the resin discharged in the subcavity are connected. For this reason, after taking out the molded product from the molding die, a cutting process for cutting the portion discharged into the sub-cavity from the molded product is separately required. For example, when a two-layer tubular hollow body is formed, a cutting step is required in which the portion discharged into the subcavity is cut from the molded product in both the outer layer portion forming step and the inner layer portion forming step.

  Further, in the fluid assist molding described in Patent Documents 1 and 2, since the floating core is discharged into the subcavity, the molded tubular hollow body has an inner peripheral surface having the same diameter in the entire region. For this reason, for example, when the connecting member is inserted into the tubular hollow body, it is difficult to position the connecting member with high accuracy because the connecting member is not locked to the inner peripheral surface of the tubular hollow body.

  Then, an object of this invention is to provide the tubular hollow body shaping | molding die and tubular hollow body shaping | molding method which can aim at reduction of a man-hour. Moreover, an object of this invention is to provide the tubular hollow body which can latch another member in an internal peripheral surface.

  A first tubular hollow body molding die according to one aspect of the present invention is a tubular hollow body molding die for molding a tubular hollow body, and has a shape of the outer peripheral surface of the tubular hollow body, and the resin A main cavity to be injected, a pressurization port formed at one end of the main cavity and pressurized fluid is press-fitted into the main cavity, and a discharge port formed at the other end of the main cavity to discharge the resin from the main cavity And a floating core detachably provided on the pressurization port, and a cylindrical stopper extending from the discharge port toward the pressurization port along the axis of the main cavity, the pressurization fluid from the pressurization port When the floating core moves through the main cavity by being press-fitted, the floating core is pressed against the inner peripheral surface of the stopper.

  In this tubular hollow body molding die, when the pressurized fluid is injected from the pressurized port after injecting the resin into the main cavity, the resin is discharged from the discharge port, and the floating core moves through the main cavity to move the stopper. Pressed against the inner surface. As a result, the resin remaining in the main cavity and the resin discharged from the main cavity are cut or almost cut. For this reason, by taking out the resin molded product from the main cavity, a molded product from which the portion discharged from the main cavity is removed, that is, a tubular hollow body can be obtained. As described above, since it is not necessary to provide a separate process for cutting the portion discharged from the main cavity, the number of man-hours can be reduced.

  In the first tubular hollow body molding die, the outer peripheral surface of the stopper may be separated from the peripheral wall surface of the main cavity.

  In this tubular hollow body molding die, since the outer peripheral surface of the stopper is separated from the peripheral wall surface of the main cavity, the end on the discharge port side of the molded product is formed by the peripheral wall surface of the main cavity and the outer peripheral surface of the stopper. Is done. For this reason, regardless of the positional relationship between the floating core and the stopper, the end of the molded product on the discharge port side can be molded with high accuracy.

  In the first tubular hollow body molding die, the outer diameter of the stopper may be larger than the outer diameter of the floating core.

  In this tubular hollow body molding die, since the outer diameter of the stopper is larger than the outer diameter of the floating core, the resin molded product can be easily taken out from the main cavity after the floating core is pressed against the inner peripheral surface of the stopper.

  By the way, when the tubular hollow body is molded by this tubular hollow body molding die, the inner peripheral surface of the end of the tubular hollow body is molded by the outer peripheral surface of the stopper, and the inner peripheral surface of the remaining portion of the tubular hollow body is Molded by the outer peripheral surface of the floating core. Since the outer diameter of the stopper is larger than the outer diameter of the floating core, the inner diameter of the end portion of the tubular hollow body is larger than the inner diameter of the remaining portion of the tubular hollow body. Thereby, since a level | step difference can be provided in the internal peripheral surface of a tubular hollow body, when inserting a connection member in a tubular hollow body, for example, a connection member can be positioned with high precision.

  A second tubular hollow body molding die according to one aspect of the present invention is a tubular hollow body molding for molding a multilayer hollow tubular body having an outer layer portion and an inner layer portion laminated on the inner layer side of the outer layer portion. A first mold part for molding the outer layer part and a second mold part for molding the inner layer part, wherein the first mold part has the shape of the outer peripheral surface of the outer layer part A first main cavity into which the first resin is injected, a first pressurization port formed at one end of the first main cavity and pressurizing the first pressurization fluid into the first main cavity, and a first main cavity A first discharge port for discharging the first resin from the first main cavity, a first floating core detachably provided in the first pressure port, and an axis of the first main cavity. And a cylindrical first stopper extending from the first discharge port toward the first pressure port side When the first pressurized fluid is pressed from the first pressurized port and the first floating core moves through the first main cavity, the first floating core is pressed against the inner peripheral surface of the first stopper, The mold part has the shape of the outer peripheral surface of the outer layer part and is formed at one end of the second main cavity and the second main cavity into which the second resin is injected, and pressurizes the second pressurized fluid into the second main cavity. A second pressure port that is formed at the other end of the second main cavity, a second discharge port that discharges the second resin from the second main cavity, and a second diameter that is smaller than the first floating core. A second floating core detachably provided on the pressure port; and a cylindrical second stopper extending from the second discharge port toward the second pressure port along the axis of the second main cavity. , Second pressure from the second pressure port When the second floating core by the fluid is pressed moves a second main cavity, the second floating core is pressed against the inner peripheral surface of the second stopper.

  In this tubular hollow body molding die, after injecting the first resin into the first main cavity and then press-fitting the first pressurized fluid from the first pressurized port, the first resin is discharged from the first outlet, The first floating core moves through the first main cavity and is pressed against the inner peripheral surface of the first stopper. Accordingly, the first resin remaining in the first main cavity and the first resin discharged from the first main cavity are cut or almost cut. For this reason, the molded product from which the part discharged | emitted from the 1st main cavity was removed, ie, an outer-layer part, can be obtained by taking out the 1st molded product of 1st resin from a 1st main cavity. And after installing the 1st molded product taken out from the 1st main cavity in the 2nd main cavity, injecting the 2nd resin into the 2nd main cavity, and press-fitting the 2nd pressurization fluid from the 2nd pressurization port The second resin is discharged from the second discharge port, and the second floating core moves through the second main cavity and is pressed against the inner peripheral surface of the second stopper. Thereby, the second resin remaining in the second main cavity and the second resin discharged from the second main cavity are cut or almost cut. For this reason, by removing the second molded product of the second resin from the second main cavity, the molded product from which the portion discharged from the second main cavity has been removed, that is, the inner layer portion laminated on the inner layer side of the outer layer portion. Can be obtained. As described above, since it is not necessary to separately provide a step of cutting the portion discharged from the first main cavity and a step of cutting the portion discharged from the second main cavity, the number of man-hours can be reduced.

  In the second tubular hollow body molding die, the outer peripheral surface of the first stopper is separated from the peripheral wall surface of the first main cavity, and the outer peripheral surface of the second stopper is separated from the peripheral wall surface of the second main cavity. It may be.

  In this tubular hollow body molding die, since the outer peripheral surface of the first stopper is separated from the peripheral wall surface of the first main cavity, the end on the first discharge port side of the outer layer portion is the peripheral wall surface of the first main cavity. And the outer peripheral surface of the first stopper. For this reason, the edge part by the side of the 1st discharge port of an outer layer part can be shape | molded with high precision irrespective of the positional relationship of a 1st floating core and a 1st stopper. Similarly, since the outer peripheral surface of the second stopper is separated from the peripheral wall surface of the second main cavity, the end on the second discharge port side of the inner layer portion is the outer peripheral surface of the second main cavity and the second stopper. And the surface. For this reason, the edge part by the side of the 2nd discharge port of an inner layer part can be shape | molded with high precision irrespective of the positional relationship of a 2nd floating core and a 2nd stopper.

  In the second tubular hollow body, the outer diameter of the first stopper may be larger than the outer diameter of the first floating core, and the outer diameter of the second stopper may be larger than the outer diameter of the second floating core.

  In this tubular hollow body molding die, since the outer diameter of the first stopper is larger than the outer diameter of the first floating core, after pressing the first floating core against the inner peripheral surface of the first stopper, It becomes easy to take out the first molded product of the first resin. Similarly, since the outer diameter of the second stopper is larger than the outer diameter of the second floating core, after the second floating core is pressed against the inner peripheral surface of the second stopper, the second resin is discharged from the second main cavity to the second resin. It becomes easy to take out the molded product.

  By the way, when the tubular hollow body is molded by this tubular hollow body molding die, the inner peripheral surface of the end portion of the inner layer portion is formed by the outer peripheral surface of the second stopper, and the inner peripheral surface of the remaining portion of the inner layer portion is Molded by the outer peripheral surface of the second floating core. Since the outer diameter of the second stopper is larger than the outer diameter of the second floating core, the inner diameter of the end portion of the inner layer portion is larger than the inner diameter of the remaining portion of the inner layer portion. Thereby, for example, when the inner layer portion is the innermost layer of the tubular hollow body, a step can be provided on the inner peripheral surface of the tubular hollow body. For example, when the coupling member is inserted into the tubular hollow body, The member can be positioned with high accuracy.

  In the above tubular hollow body molding die, the first floating core may include a convex portion protruding from the outer peripheral surface.

  In this tubular hollow body molding die, since the convex portion protrudes from the outer peripheral surface of the first floating core, the concave portion corresponding to the convex portion can be formed on the inner peripheral surface of the outer layer portion. Thereby, since an outer layer part and an inner layer part are couple | bonded by an uneven structure, the coupling strength of an outer layer part and an inner layer part can be improved.

  A third tubular hollow body molding die according to one aspect of the present invention is a tubular hollow body molding for molding a multilayer hollow tubular body having an outer layer portion and an inner layer portion laminated on the inner layer side of the outer layer portion. A first mold part for molding the outer layer part and a second mold part for molding the inner layer part, wherein the first mold part has the shape of the outer peripheral surface of the outer layer part The second mold part has the shape of the outer peripheral surface of the inner layer part, and the second main cavity into which the second resin is injected, and the second main cavity. The second pressurization port is formed at one end of the second main cavity and pressurizes the second pressurization fluid into the second main cavity, and is formed at the other end of the second main cavity to discharge the second resin from the second main cavity. A second discharge port, a second floating core detachably provided at the second pressure port, and a second main cavity A second stopper extending from the second discharge port toward the second pressurization port along the axis, and when the second pressurization fluid is press-fitted from the second pressurization port, the second floating core is When the second main cavity is moved, the second floating core is pressed against the inner peripheral surface of the second stopper.

  In this tubular hollow body molding die, after injecting the second resin into the second main cavity and then press-fitting the second pressurized fluid from the second pressurized port, the second resin is discharged from the second discharge port, The second floating core moves through the second main cavity and is pressed against the inner peripheral surface of the second stopper. Thereby, the second resin remaining in the second main cavity and the second resin discharged from the second main cavity are cut or almost cut. For this reason, the molded product from which the part discharged | emitted from the 2nd main cavity was removed by extracting the 2nd molded product of 2nd resin from a 2nd main cavity, ie, an inner layer part, can be obtained. Then, the second molded product taken out from the second main cavity is placed in the first main cavity, the first resin is injected into the first main cavity, and the first molded product of the first resin is taken out from the first main cavity. Thus, the inner layer portion laminated on the inner layer side of the outer layer portion can be obtained. As described above, since it is not necessary to provide a separate process for cutting the portion discharged from the second main cavity, the number of man-hours can be reduced.

  In the third tubular hollow body molding die, the outer peripheral surface of the second stopper may be separated from the peripheral wall surface of the second main cavity.

  In this tubular hollow body molding die, since the outer peripheral surface of the second stopper is separated from the peripheral wall surface of the second main cavity, the end on the second discharge port side of the inner layer portion is the peripheral wall surface of the second main cavity. And the outer peripheral surface of the second stopper. For this reason, the edge part by the side of the 2nd discharge port of an inner layer part can be shape | molded with high precision irrespective of the positional relationship of a 2nd floating core and a 2nd stopper.

  In the third tubular hollow body molding die, the outer diameter of the second stopper may be larger than the outer diameter of the second floating core.

  In this tubular hollow body molding die, since the outer diameter of the second stopper is larger than the outer diameter of the second floating core, after pressing the second floating core against the inner peripheral surface of the second stopper, It becomes easy to take out the second molded product of the second resin.

  By the way, when the tubular hollow body is molded by this tubular hollow body molding die, the inner peripheral surface of the end portion of the inner layer portion is formed by the outer peripheral surface of the second stopper, and the inner peripheral surface of the remaining portion of the inner layer portion is Molded by the outer peripheral surface of the second floating core. Since the outer diameter of the second stopper is larger than the outer diameter of the second floating core, the inner diameter of the end portion of the inner layer portion is larger than the inner diameter of the remaining portion of the inner layer portion. Thereby, for example, when the inner layer portion is the innermost layer of the tubular hollow body, a step can be provided on the inner peripheral surface of the tubular hollow body. For example, when the coupling member is inserted into the tubular hollow body, The member can be positioned with high accuracy.

  In the third tubular hollow body molding die, the second main cavity may be provided with a recess that is recessed by the thickness of the outer layer portion.

  In this tubular hollow body molding die, since the concave portion is formed in the second main cavity, the convex portion corresponding to the concave portion can be formed on the outer peripheral surface of the inner layer portion. Thereby, since an outer layer part and an inner layer part are couple | bonded by an uneven structure, the coupling strength of an outer layer part and an inner layer part can be improved. Moreover, since the concave portion is recessed by the thickness of the outer layer portion, the inner layer portion can be positioned when the inner layer portion is installed in the first main cavity by the convex portion formed on the outer peripheral surface of the inner layer portion. it can.

  A first tubular hollow body molding method according to one aspect of the present invention is a tubular hollow body molding method for molding a tubular hollow body using the first tubular hollow body molding die described above. The injection process of injecting the resin, and pressurizing the pressurized fluid from the pressurized port moves the floating core from the pressurized port toward the discharge port, discharges the resin from the discharge port, and moves the floating core inside the stopper. A core moving step for pressing against the peripheral surface, and a removing step for taking out a resin molded product from the main cavity.

  In this tubular hollow body forming method, after the resin is injected into the main cavity, a pressurized fluid is press-fitted from the pressurizing port, the resin is discharged from the discharge port, and the floating core is pressed against the inner peripheral surface of the stopper. As a result, the resin remaining in the main cavity and the resin discharged from the main cavity are cut or almost cut. For this reason, by taking out the resin molded product from the main cavity, a molded product from which the portion discharged from the main cavity is removed, that is, a tubular hollow body can be obtained. As described above, since it is not necessary to provide a separate process for cutting the portion discharged from the main cavity, the number of man-hours can be reduced.

  A second tubular hollow body molding method according to one aspect of the present invention is a multilayer including an outer layer portion and an inner layer portion laminated on the inner layer side of the outer layer portion using the second tubular hollow body molding die. A tubular hollow body forming method for forming a tubular hollow body having a structure, comprising: a first forming step for forming an outer layer portion; and a second forming step for forming an inner layer portion after the first forming step, One molding process includes a first injection process for injecting the first resin into the first main cavity, and after the first injection process, the first pressurized fluid is press-fitted from the first pressurized port to form the first floating core. A first core moving step of moving from the first pressure port toward the first outlet, discharging the first resin from the first outlet and pressing the first floating core against the inner peripheral surface of the first stopper; 1st molding of 1st resin from 1st main cavity after 1st core movement process A first take-out step, and a second molding step is a step of installing the first molded product in the second main cavity, and a step of injecting a second resin into the second main cavity after the installation step. After the second injection step and the second injection step, the second floating core is moved from the second pressurization port toward the second discharge port side by press-fitting the second pressurization fluid from the second pressurization port, After the second resin is discharged from the second discharge port and the second floating core is pressed against the inner peripheral surface of the second stopper, and after the second core movement step, the second resin is discharged from the second main cavity. A second removal step of taking out the second molded product.

  In this tubular hollow body forming method, after injecting the first resin into the first main cavity, the first pressurized fluid is press-fitted from the first pressure port, and the first resin is discharged from the first outlet. Press one floating core against the inner peripheral surface of the first stopper. Accordingly, the first resin remaining in the first main cavity and the first resin discharged from the first main cavity are cut or almost cut. For this reason, the molded product from which the part discharged | emitted from the 1st main cavity was removed, ie, an outer-layer part, can be obtained by taking out a 1st molded product from a 1st main cavity. Then, after the first molded product taken out from the first main cavity is placed in the second main cavity and the second resin is injected into the second main cavity, the second pressurized fluid is press-fitted from the second pressure port. The second resin is discharged from the second discharge port and the second floating core is pressed against the inner peripheral surface of the second stopper. Thereby, the second resin remaining in the second main cavity and the second resin discharged from the second main cavity are cut or almost cut. For this reason, by taking out the second molded product from the second main cavity, it is possible to obtain a molded product from which the portion discharged from the second main cavity is removed, that is, an inner layer portion laminated on the inner layer side of the outer layer portion. it can. As described above, since it is not necessary to separately provide a step of cutting the portion discharged from the first main cavity and a step of cutting the portion discharged from the second main cavity, the number of man-hours can be reduced.

  In the second tubular hollow body forming method, in the first forming step, a recess may be formed on the inner peripheral surface of the first molded product.

  In this tubular hollow body molding method, the second resin enters the concave portion in the second molding step following the first molding step by molding the concave portion on the inner peripheral surface of the first molded product. Thereby, since an outer layer part and an inner layer part are couple | bonded by an uneven structure, the coupling strength of an outer layer part and an inner layer part can be improved.

  A third tubular hollow body molding method according to one aspect of the present invention is a multilayer comprising an outer layer portion and an inner layer portion laminated on the inner layer side of the outer layer portion using the third tubular hollow body molding die. A tubular hollow body molding method for molding a tubular hollow body having a structure, comprising: a second molding step for molding an inner layer portion; and a first molding step for molding an outer layer portion after the second molding step, The second molding step includes a second injection step of injecting a second resin into the second main cavity, and a second pressurized core is pressed into the second floating core after the second injection step by pressing the second pressurized fluid. A second core moving step of moving from the second pressure port toward the second discharge port side to discharge the second resin from the second discharge port and pressing the second floating core against the inner peripheral surface of the second stopper; After the second core moving step, the second resin is secondly formed from the second main cavity. A second take-out step of taking out the product, and the first molding step injects the first resin into the first main cavity after the installation step of installing the second molded product in the first main cavity. A first injection step; and a first removal step of taking out a first molded product of the first resin from the first main cavity after the first injection step.

  In this tubular hollow body forming method, after injecting the second resin into the second main cavity, the second pressurized fluid is press-fitted from the second pressure port, and the second resin is discharged from the second outlet. Press the two floating cores against the inner peripheral surface of the second stopper. Thereby, the second resin remaining in the second main cavity and the second resin discharged from the second main cavity are cut or almost cut. For this reason, the molded product from which the part discharged | emitted from the 2nd main cavity was removed, ie, an inner layer part, can be obtained by taking out a 2nd molded product from the 2nd main cavity. Then, the second molded product taken out from the second main cavity is placed in the first main cavity, the first resin is injected into the first main cavity, and the first molded product of the first resin is taken out from the first main cavity. Thus, the inner layer portion laminated on the inner layer side of the outer layer portion can be obtained. As described above, since it is not necessary to separately provide a step of cutting the portion discharged from the first main cavity and a step of cutting the portion discharged from the second main cavity, the number of man-hours can be reduced.

  In the third tubular hollow body forming method, in the second forming step, a convex portion protruding by the thickness of the outer layer portion may be formed on the outer peripheral surface of the second molded product.

  In this tubular hollow body molding method, since the convex portion is molded on the outer peripheral surface of the second molded product, the first resin surrounds the convex portion in the first molding step subsequent to the second molding step. Thereby, since an outer layer part and an inner layer part are couple | bonded by an uneven structure, the coupling strength of an outer layer part and an inner layer part can be improved. Moreover, since the convex portion protrudes by the thickness of the outer layer portion, the inner layer portion can be positioned by the convex portion when the inner layer portion is installed in the first main cavity.

  In the second or third tubular hollow body forming method, the first resin and the second resin may be different from each other.

  In this tubular hollow body molding method, since the first resin and the second resin are different from each other, each layer can have various properties.

  The tubular hollow body according to one aspect of the present invention is a resin-made tubular hollow body, and the inner peripheral surface of at least one end of the tubular hollow body includes a first inner peripheral surface portion and a first inner peripheral surface portion. A second inner peripheral surface portion reaching an end surface of the tubular hollow body, and an inner diameter of the second inner peripheral surface portion is larger than an inner diameter of the first inner peripheral surface portion.

  In this tubular hollow body, the inner diameter of the second inner peripheral surface portion is larger than the inner diameter of the first inner peripheral surface portion at at least one end. Thereby, since a level | step difference can be provided in the internal peripheral surface of a tubular hollow body, when inserting a connection member in a tubular hollow body, for example, a connection member can be positioned with high precision.

  The tubular hollow body may include an outer layer portion and an inner layer portion laminated on the inner layer side of the outer layer portion.

  Since this tubular hollow body has a multilayer structure including at least an outer layer portion and an inner layer portion, the resins of the respective layers can be made different from each other. Thereby, each layer can have various properties.

  In the tubular hollow body, two or more bent portions may be provided along the axis of the tubular hollow body.

  Since this tubular hollow body is provided with two or more bent portions, it can be arranged in various applications and places.

  According to the tubular hollow body molding die and the tubular hollow body molding method according to one aspect of the present invention, the number of steps can be reduced. Moreover, according to the tubular hollow body which concerns on one side surface of this invention, an other member can be latched in an internal peripheral surface.

It is a schematic sectional drawing of the tubular hollow body which concerns on 1st embodiment. It is a schematic sectional drawing of the hollow body shaping | molding die concerning 1st embodiment. It is a schematic sectional drawing which shows the injection | emission process of 1st embodiment. It is a schematic sectional drawing which shows the core movement process of 1st embodiment. It is a schematic sectional drawing of the tubular hollow body which concerns on 2nd embodiment. It is a schematic sectional drawing of the hollow body shaping | molding die concerning 2nd embodiment. It is a schematic sectional drawing which shows the 1st injection process of 2nd embodiment. It is a schematic sectional drawing which shows the 1st core movement process of 2nd embodiment. It is a schematic sectional drawing which shows the installation process of 2nd embodiment. It is a schematic sectional drawing which shows the 2nd injection process of 2nd embodiment. It is a schematic sectional drawing which shows the 2nd core moving process of 2nd embodiment. 12 (a) to 12 (3) are schematic cross-sectional views of a hollow body mold according to the third embodiment. It is a schematic sectional drawing of the tubular hollow body which concerns on 4th embodiment. 14A to 14D are examples of cross-sectional views taken along line XIV-XIV in FIG. It is a schematic sectional drawing of the hollow body shaping | molding die which concerns on 4th embodiment. It is a schematic sectional drawing which shows the 2nd injection process of 4th embodiment. It is a schematic sectional drawing which shows the 2nd core moving process of 4th embodiment. It is a schematic sectional drawing which shows the installation process of 4th embodiment. It is a schematic sectional drawing which shows the 1st injection process of 4th embodiment. It is a schematic sectional drawing of the tubular hollow body of a modification.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected about the element which is the same or it corresponds in each figure, and the overlapping description is abbreviate | omitted.

[First embodiment]
First, the tubular hollow body 1 according to the present embodiment will be described.

  As shown in FIG. 1, the tubular hollow body 1 according to the present embodiment is a resin hollow body formed in an elongated tubular shape from one end 2 to the other end 3. The tube shape of the tubular hollow body 1 is not particularly limited. For example, the tubular hollow body 1 may be a circular tube having a circular cross section of the outer peripheral surface 4 and the inner peripheral surface 5. In the present embodiment, the tubular hollow body 1 is described as being circular.

  The tubular hollow body 1 includes two or more bent portions 6 along the axis L1 of the tubular hollow body 1. In the present embodiment, the tubular hollow body 1 will be described as including two bent portions 6 along the axis L1 of the tubular hollow body 1. The position, shape (curvature), length, and the like of the bent portion 6 are not particularly limited.

  The outer peripheral surface 4 of the tubular hollow body 1 is provided with a fixing plate portion 7 for fixing the tubular hollow body 1 to another member such as an engine. The number, position, size, shape and the like of the fixed plate portion 7 are not particularly limited. Further, the fixed plate portion 7 is not necessarily provided on the outer peripheral surface 4 of the tubular hollow body 1.

  The inner peripheral surface 5 of at least one end of the tubular hollow body 1 includes a first inner peripheral surface portion 5a and a second inner peripheral surface portion 5b having different inner diameters. In the present embodiment, the first inner peripheral surface portion 5a and the second inner peripheral surface portion 5b are described as being provided at the end portion of the tubular hollow body 1 on the other end 3 side. The first inner peripheral surface portion 5 a is formed in a region separated from the other end 3. The second inner peripheral surface portion 5 b is formed in a region extending from the first inner peripheral surface portion 5 a to the other end 3. The inner diameter of the second inner peripheral surface portion 5b is larger than the inner diameter of the first inner peripheral surface portion 5a. The length of the 2nd inner peripheral surface part 5b in the axis line L1 direction of the tubular hollow body 1 is not specifically limited, It can set arbitrarily.

  Next, the tubular hollow body molding die 10 according to this embodiment will be described.

  As shown in FIG. 2, the tubular hollow body molding die 10 according to the present embodiment is a mold for molding the tubular hollow body 1 by fluid assist molding. The tubular hollow body molding die 10 includes a main cavity 11, a pressure port 12, an injector 13, a discharge port 14, a subcavity 15, a floating core 16, and a stopper 17.

  The main cavity 11 is a cavity in which the resin is injected in the shape of the outer peripheral surface 4 of the tubular hollow body 1. The pressurization port 12 is a port that is formed at one end of the main cavity 11 and pressurizes a pressurized fluid into the main cavity 11. The injector 13 is an injection device that is in communication with the pressure port 12 and injects a pressurized fluid. The discharge port 14 is formed at the other end of the main cavity 11 and discharges the resin from the main cavity 11. The sub cavity 15 is a cavity communicated with the discharge port 14 and stores the resin discharged from the discharge port 14.

  The floating core 16 is detachably attached to the pressure port 12. The floating core 16 is provided in the main cavity 11 with the pressurizing port 12 as the back so as to be pressed by the pressurizing fluid press-fitted from the pressurizing port 12. The maximum diameter of the floating core 16 is substantially the same as the inner diameter of the tubular hollow body 1 and is smaller than the inner diameter of the main cavity 11. The shape of the outer peripheral surface of the floating core 16 is not particularly limited, and may be a shell shape, a conical shape, a hemispherical shape, a spherical shape, or the like. In the present embodiment, the outer peripheral surface of the floating core 16 will be described as having a conical shape with the tip rounded and the rear end having the maximum diameter.

  The stopper 17 is formed in a cylindrical shape having the axis L11 of the main cavity 11 as the central axis. The stopper 17 extends from the discharge port 14 toward the pressure port 12 along the axis L11 of the main cavity 11. The discharge port 14 is formed on the inner peripheral surface 17 a side of the stopper 17. Therefore, the resin injected into the main cavity 11 is discharged from the discharge port 14 to the sub cavity 15 only through the inner peripheral surface 17a side of the stopper 17.

  The inner peripheral surface 17 a of the stopper 17 is formed in a conical shape (funnel shape) whose diameter is increased toward the pressurizing port 12. The minimum inner diameter of the inner peripheral surface 17 a of the stopper 17 is smaller than the maximum diameter of the floating core 16. For this reason, when the floating core 16 moves through the main cavity 11 by pressurizing the pressurized fluid from the pressurized port 12, the floating core 16 is pressed against the inner peripheral surface 17 a of the stopper 17. The floating core 16 is preferably pressed against the inner peripheral surface 17a of the stopper 17 on the entire circumference. When the inner peripheral surface 17a of the stopper 17 and the outer peripheral surface of the floating core 16 are conical, the apex angle θ2 of the inner peripheral surface 17a of the stopper 17 is substantially the same as the apex angle θ1 of the outer peripheral surface of the floating core 16, or It is preferably slightly smaller than the apex angle θ1 of the outer peripheral surface of the floating core 16.

  The outer peripheral surface 17b of the stopper 17 has the same diameter over the entire region in the direction of the axis L11 of the main cavity 11. The outer diameter of the stopper 17 is larger than the outer diameter of the floating core 16. Further, the outer peripheral surface 17 b of the stopper 17 is separated from the peripheral wall surface 11 a of the main cavity 11. Therefore, the main cavity 11 has a space for the injected resin to enter between the peripheral wall surface 11 a of the main cavity 11 and the outer peripheral surface 17 b of the stopper 17. The peripheral wall surface 11 a of the main cavity 11 refers to a wall surface having a circular cross section for forming the outer peripheral surface 4 of the tubular hollow body 1.

  Next, the tubular hollow body forming method according to the present embodiment will be described.

  The tubular hollow body forming method according to the present embodiment is a method of forming the tubular hollow body 1 using the tubular hollow body forming die 10. In this tubular hollow body forming method, first, an injection process is performed, then a core moving process is performed, and then an extraction process is performed.

  As shown in FIG. 3, in the injection process, the discharge port 14 is closed by a hydraulic cylinder or the like, and the resin R is injected into the main cavity 11. As the resin R injected into the main cavity 11, for example, aromatic polyamide resin, ethylene-tetrafluoroethylene copolymer (ETFE), or polyphenylene sulfide (PPS) having high heat resistance, chemical resistance and high strength can be used. . The tubular hollow body molding die 10 is formed with one or a plurality of gates (not shown) communicating with the main cavity 11, and the heat-melted resin R is injected from the gates into the main cavity 11. Then, the resin R is filled in the main cavity 11. At this time, the injected resin R enters the space between the peripheral wall surface 11 a of the main cavity 11 and the stopper 17.

  In the core moving process, the discharge port 14 is opened by a hydraulic cylinder or the like. Then, as shown in FIG. 4, pressurized fluid is press-fitted from the pressurized port 12, and the floating core 16 is moved from the pressurized port 12 toward the discharge port 14. That is, when the pressurized fluid is press-fitted into the main cavity 11 from the pressurized port 12, the floating core 16 provided in the pressurized port 12 is pressed by the pressurized fluid, thereby along the axis L11 of the main cavity 11. The pressure port 12 moves toward the discharge port 14 side. As the pressurized fluid, a gas or liquid that does not react with or be compatible with the resin under the temperature and pressure of injection molding can be used. Specifically, nitrogen gas, carbon dioxide gas, air, water, glycerin, liquid paraffin Etc. can be used. And the resin R is discharged | emitted from the discharge port 14 by moving the floating core 16 in this way. Thereby, the inner peripheral surface 5 of the tubular hollow body 1 is molded. Further, the floating core 16 is pressed against the inner peripheral surface 17 a of the stopper 17 by moving the floating core 16 in this way. Then, the resin R remaining in the main cavity 11 and the resin R discharged from the main cavity 11 to the sub-cavity 15 are cut or almost cut.

  In the extraction step, the molded product M of the resin R is extracted from the main cavity 11 by a hydraulic arm or the like. At this time, the resin R remaining in the main cavity 11 and the resin R discharged from the main cavity 11 to the sub-cavity 15 are cut or almost cut. For this reason, by taking out the molded product M from the main cavity 11, a molded product from which the portion discharged from the main cavity 11 to the sub-cavity 15 is removed, that is, the tubular hollow body 1 is obtained. Thereby, shaping | molding of the tubular hollow body 1 is complete | finished. Note that the portion discharged from the subcavity 15 to the subcavity 15 and the floating core 16 are taken out at an arbitrary timing.

  Thus, in the tubular hollow body molding die 10 and the tubular hollow body molding method according to the present embodiment, when the pressurized fluid is injected from the pressurized port 12 after the resin R is injected into the main cavity 11, the resin R is The floating core 16 moves through the main cavity 11 and is pressed against the inner peripheral surface 17 a of the stopper 17. Thereby, the resin R remaining in the main cavity 11 and the resin R discharged from the main cavity 11 are cut or almost cut. For this reason, by taking out the molded product M of the resin R from the main cavity 11, the molded product M from which the portion discharged from the main cavity 11 is removed, that is, the tubular hollow body 1 can be obtained. As described above, since it is not necessary to provide a separate process for cutting the portion discharged from the main cavity 11, man-hours can be reduced.

  Further, since the outer peripheral surface 17 b of the stopper 17 is separated from the peripheral wall surface 11 a of the main cavity 11, the end of the molded product M on the discharge port 14 side is the peripheral wall surface 11 a of the main cavity 11 and the outer peripheral surface 17 b of the stopper 17. And then molded. For this reason, regardless of the positional relationship between the floating core 16 and the stopper 17, the end of the molded product M on the discharge port 14 side can be molded with high accuracy.

  Further, since the outer diameter of the stopper 17 is larger than the outer diameter of the floating core 16, the molded product M of the resin R can be easily taken out from the main cavity 11 after the floating core 16 is pressed against the inner peripheral surface 17 a of the stopper 17.

  By the way, when the tubular hollow body 1 is molded by the tubular hollow body molding die 10, the inner peripheral surface 5 at the end of the tubular hollow body 1 is formed by the outer peripheral surface 17 b of the stopper 17, and the remaining part of the tubular hollow body 1 is formed. The inner peripheral surface 5 of the part is formed by the outer peripheral surface of the floating core 16. Since the outer diameter of the stopper 17 is larger than the outer diameter of the floating core 16, the inner diameter of the end portion of the tubular hollow body 1 is larger than the inner diameter of the remaining portion of the tubular hollow body 1. Thereby, since a level | step difference can be provided in the internal peripheral surface 5 of the tubular hollow body 1, when inserting a connection member in the tubular hollow body 1, a connection member can be positioned with high precision.

  In the tubular hollow body 1 according to the present embodiment, the first inner circumferential surface portion 5a and the second inner circumferential surface portion 5b are formed on the inner circumferential surface 5 of the end portion on the other end 3 side of the tubular hollow body 1, and the first The inner diameter of the two inner peripheral surface portions 5b is larger than the inner diameter of the first inner peripheral surface portion 5a. Thereby, since a level | step difference can be provided in the internal peripheral surface 5 of the tubular hollow body 1, when inserting a connection member in the tubular hollow body 1, a connection member can be positioned with high precision.

  Moreover, since the 2 or more bending part 6 is provided, it can arrange | position in various uses and places.

[Second Embodiment]
Next, a second embodiment will be described.

  The tubular hollow body according to the second embodiment is basically the same as the tubular hollow body 1 according to the first embodiment, but only the first embodiment has a multilayer structure in which a plurality of resin layers are laminated. It differs from the tubular hollow body 1 which concerns on a form. For this reason, below, only the matter different from the tubular hollow body 1 which concerns on 1st embodiment is demonstrated, and description of the matter similar to the tubular hollow body 1 which concerns on 1st embodiment is abbreviate | omitted.

  As shown in FIG. 5, the tubular hollow body 1A according to the present embodiment has a multilayer structure in which a plurality of resin layers are laminated. In the present embodiment, the tubular hollow body 1 </ b> A will be described as having a two-layer structure including an outer layer portion 8 and an inner layer portion 9 laminated on the inner layer side of the outer layer portion 8. As a material of the outer layer part 8, for example, a resin having properties excellent in impact resistance, corrosion resistance, heat resistance and the like can be used. As a material of the inner layer portion 9, for example, a resin having properties excellent in low permeability, corrosion resistance, chemical resistance, and the like can be used.

  Next, the tubular hollow body molding die 20 according to this embodiment will be described.

  As shown in FIG. 6, the tubular hollow body molding die 20 according to this embodiment forms a tubular hollow body 1 </ b> A having a multilayer structure including an outer layer portion 8 and an inner layer portion 9 laminated on the inner layer side of the outer layer portion 8. It is a mold to do. The tubular hollow body molding die 20 is a mold for molding the inner layer portion 9 after molding the outer layer portion 8. The tubular hollow body molding die 20 includes a first mold portion 20a for molding the outer layer portion 8 by fluid-assisted molding similar to the tubular hollow body molding die 10 of the first embodiment, and the tubular hollow body of the first embodiment. A second mold part 20b for molding the inner layer part 9 by fluid-assisted molding similar to the body molding mold 10; In the present embodiment, the first mold part 20a and the second mold part 20b are described as being integrally formed. However, the first mold part 20a and the second mold part 20b are formed separately. It may be.

  The first mold portion 20 a includes a first main cavity 21 corresponding to the main cavity 11, a first pressure port 22 corresponding to the pressure port 12, a first injector 23 corresponding to the injector 13, and the discharge port 14. A corresponding first discharge port 24, a first subcavity 25 corresponding to the subcavity 15, a first floating core 26 corresponding to the floating core 16, and a first stopper 27 corresponding to the stopper 17 are provided. .

  The 1st main cavity 21 makes the shape of the outer peripheral surface (outer peripheral surface 4 of 1 A of tubular hollow bodies) of the outer layer part 8, and is a cavity where 1st resin is inject | emitted. The first pressurized port 22 is a port that is formed at one end of the first main cavity 21 and into which the first pressurized fluid is press-fitted into the first main cavity 21. The first injector 23 is an injection device that communicates with the first pressurization port 22 and injects the first pressurization fluid. The first discharge port 24 is formed at the other end of the first main cavity 21 and discharges the first resin from the first main cavity 21. The first subcavity 25 is a cavity communicated with the first discharge port 24 and stores the first resin discharged from the first discharge port 24.

  The first floating core 26 is detachably attached to the first pressure port 22. The first floating core 26 is provided in the first main cavity 21 with the first pressurization port 22 as the back so as to be pressed by the first pressurization fluid press-fitted from the first pressurization port 22. . The maximum diameter of the first floating core 26 is substantially the same as the inner diameter of the outer layer portion 8 and is smaller than the inner diameter of the first main cavity 21. The shape of the outer peripheral surface of the first floating core 26 is not particularly limited, and may be a shell shape, a conical shape, a hemispherical shape, a spherical shape, or the like. In the present embodiment, the outer peripheral surface of the first floating core 26 will be described as having a conical shape with the leading end rounded and the trailing end having the maximum diameter.

  The first stopper 27 is formed in a cylindrical shape having the axis L21 of the first main cavity 21 as the central axis. The first stopper 27 extends from the first discharge port 24 toward the first pressure port 22 along the axis L21 of the first main cavity 21. The first discharge port 24 is formed on the inner peripheral surface 27 a side of the first stopper 27. Therefore, the first resin injected into the first main cavity 21 is discharged from the first discharge port 24 to the first sub cavity 25 only through the inner peripheral surface 27 a side of the first stopper 27.

  The inner peripheral surface 27 a of the first stopper 27 is formed in a conical shape (funnel shape) whose diameter is increased toward the first pressure port 22. The minimum inner diameter of the inner peripheral surface 27 a of the first stopper 27 is smaller than the maximum diameter of the first floating core 26. For this reason, when the first floating core 26 moves through the first main cavity 21 due to the pressurization of the first pressurized fluid from the first pressure port 22, the first floating core 26 is moved into the first stopper 27. It is pressed against the peripheral surface 27a. In addition, it is preferable that the 1st floating core 26 is pressed on the internal peripheral surface 27a of the 1st stopper 27 in the perimeter. When the inner peripheral surface 27a of the first stopper 27 and the outer peripheral surface of the first floating core 26 are conical, the apex angle θ4 of the inner peripheral surface 27a of the first stopper 27 is the apex of the outer peripheral surface of the first floating core 26. It is preferably substantially the same as the angle θ3 or slightly smaller than the apex angle θ3 of the outer peripheral surface of the first floating core 26.

  The outer peripheral surface 27b of the first stopper 27 has the same diameter over the entire region in the direction of the axis L21 of the first main cavity 21. The outer diameter of the first stopper 27 is larger than the outer diameter of the first floating core 26. Further, the outer peripheral surface 27 b of the first stopper 27 is separated from the peripheral wall surface 21 a of the first main cavity 21. Therefore, the first main cavity 21 has a space for the injected first resin to enter between the peripheral wall surface 21 a of the first main cavity 21 and the outer peripheral surface 27 b of the first stopper 27. The peripheral wall surface 21a of the first main cavity 21 refers to a wall surface having a circular cross section for forming the outer peripheral surface of the outer layer portion 8 (the outer peripheral surface 4 of the tubular hollow body 1A).

  The second mold part 20b includes a second main cavity 31, a second pressure port 32, a second injector 33, a second discharge port 34, a second sub cavity 35, a second floating core 36, a first And two stoppers 37.

  The second main cavity 31 is a cavity in which the second resin is injected in the shape of the outer peripheral surface of the outer layer portion 8 (the outer peripheral surface 4 of the tubular hollow body 1A), like the first main cavity 21. The second pressurization port 32 is a port that is formed at one end of the second main cavity 31 and into which the second pressurization fluid is press-fitted into the second main cavity 31. The second injector 33 is an injection device that communicates with the second pressurization port 32 and injects the second pressurization fluid. The second discharge port 34 is formed at the other end of the second main cavity 31 and discharges the second resin from the second main cavity 31. The second sub cavity 35 is a cavity communicated with the first discharge port 24 and stores the second resin discharged from the second discharge port 34.

  The second floating core 36 is detachably attached to the second pressure port 32. The second floating core 36 is provided in the second main cavity 31 with the second pressurization port 32 as the back so as to be pressed by the second pressurization fluid press-fitted from the second pressurization port 32. . The second floating core 36 is formed with a smaller diameter than the first floating core 26. The maximum diameter of the second floating core 36 is substantially the same as the inner diameter of the inner layer portion 9. The shape of the outer peripheral surface of the second floating core 36 is not particularly limited, and may be a shell shape, a conical shape, a hemispherical shape, a spherical shape, or the like. In the present embodiment, the outer peripheral surface of the second floating core 36 is described as having a conical shape with the tip rounded and the rear end having the maximum diameter, like the first floating core 26.

  The second stopper 37 is formed in a cylindrical shape having the axis L31 of the second main cavity 31 as the central axis. The second stopper 37 extends from the second discharge port 34 toward the second pressure port 32 side along the axis L31 of the second main cavity 31. The second discharge port 34 is formed on the inner peripheral surface 37 a side of the second stopper 37. For this reason, the second resin injected into the second main cavity 31 is discharged from the second discharge port 34 only through the inner peripheral surface 37 a side of the second stopper 37.

  The inner peripheral surface 37 a of the second stopper 37 is formed in a conical shape (funnel shape) whose diameter is increased toward the second pressure port 32. The minimum inner diameter of the inner peripheral surface 37 a of the second stopper 37 is smaller than the maximum diameter of the second floating core 36. Therefore, when the second pressurized core is moved from the second pressurized port 32 and the second floating core 36 moves through the second main cavity 31, the second floating core 36 is moved into the second stopper 37. It is pressed against the peripheral surface 37a. In addition, it is preferable that the 2nd floating core 36 is pressed on the internal peripheral surface 37a of the 2nd stopper 37 in the perimeter. When the inner peripheral surface 37a of the second stopper 37 and the outer peripheral surface of the second floating core 36 are conical, the apex angle θ6 of the inner peripheral surface 37a of the second stopper 37 is the apex of the outer peripheral surface of the second floating core 36. It is preferably substantially the same as the angle θ5 or slightly smaller than the apex angle θ5 of the outer peripheral surface of the second floating core 36.

  The outer peripheral surface 37b of the second stopper 37 has the same diameter over the entire region in the direction of the axis L31 of the second main cavity 31. The outer diameter of the second stopper 37 is larger than the outer diameter of the second floating core 36. The outer peripheral surface 37 b of the second stopper 37 is separated from the peripheral wall surface 31 a of the second main cavity 31. Therefore, the second main cavity 31 includes a space for the injected second resin to enter between the peripheral wall surface 31 a of the second main cavity 31 and the outer peripheral surface 37 b of the second stopper 37. The peripheral wall surface 31a of the second main cavity 31 refers to a wall surface having a circular cross section with which the outer peripheral surface of the outer layer portion 8 (the outer peripheral surface 4 of the tubular hollow body 1A) abuts.

  Next, the tubular hollow body forming method according to the present embodiment will be described.

  The tubular hollow body forming method according to the present embodiment is a tubular hollow body 1A having a multilayer structure including an outer layer portion 8 and an inner layer portion 9 laminated on the inner layer side of the outer layer portion 8 using a tubular hollow body forming die 20. This is a method of molding. This tubular hollow body forming method includes a first forming step for forming the outer layer portion 8 and a second forming step for forming the inner layer portion 9 after the first forming step.

  In the first molding step, first, the first injection step is performed, then the first core moving step is performed, and then the first extraction step is performed.

  As shown in FIG. 7, in the first injection step, the first discharge port 24 is closed by a hydraulic cylinder or the like, and the first resin R <b> 1 is injected into the first main cavity 21. Examples of the first resin R1 injected into the first main cavity 21 include aromatic polyamide resin having high heat resistance, chemical resistance and strength, ethylene-tetrafluoroethylene copolymer (ETFE), polyphenylene sulfide (PPS), and the like. Can be used. One or more gates (not shown) communicating with the first main cavity 21 are formed in the first mold part 20a, and the first resin R1 heated and melted is injected into the first main cavity 21 from the gate. To do. Then, the first main cavity 21 is filled with the first resin R1. At this time, the injected first resin R <b> 1 enters the space between the peripheral wall surface 21 a of the first main cavity 21 and the first stopper 27.

In the first core moving step, the first discharge port 24 is opened by a hydraulic cylinder or the like. And as shown in FIG. 8, the 1st pressurization fluid is press-fitted from the 1st pressurization port 22, and the 1st floating core 26 is moved toward the 1st discharge port 24 side from the 1st pressurization port 22. . That is, when the first pressurized fluid is pressed into the first main cavity 21 from the first pressurized port 22, the first floating core 26 provided in the first pressurized port 22 is pressed by the first pressurized fluid. Thus, the first main cavity 21 moves from the first pressure port 22 toward the first discharge port 24 along the axis L21. The first pressurized fluid that is press-fitted from the first pressurized port 22 can be the same fluid as the pressurized fluid that is press-fitted from the pressurized port 12 in the first embodiment.
And the 1st resin R1 is discharged | emitted from the 1st discharge port 24 by moving the 1st floating core 26 in this way. Thereby, the inner peripheral surface of the outer layer part 8 is shape | molded. Further, the first floating core 26 is pressed against the inner peripheral surface 27 a of the first stopper 27 by moving the first floating core 26 in this way. Then, the first resin R1 remaining in the first main cavity 21 and the first resin R1 discharged from the first main cavity 21 to the first subcavity 25 are cut or almost cut.

  In the first removal step, the first molded product M1 of the first resin R1 is removed from the first main cavity 21 by a hydraulic arm or the like. At this time, the first resin R1 remaining in the first main cavity 21 and the first resin R1 discharged from the first main cavity 21 to the first subcavity 25 are cut or almost cut off. . For this reason, by removing the first molded product M1 from the first main cavity 21, a molded product from which the portion discharged from the first main cavity 21 to the first subcavity 25 is removed, that is, the outer layer portion 8 is obtained. . In addition, the part discharged | emitted from the 1st subcavity 25 to the 1st subcavity 25 and the 1st floating core 26 are taken out at arbitrary timings.

  In the second molding step, first, an installation step is performed, then a second injection step is performed, and then a second extraction step is performed.

  As shown in FIG. 9, in the installation process, the first molded product M <b> 1 extracted in the first extraction process is installed in the second main cavity 31. Since the second main cavity 31 has the shape of the outer peripheral surface of the outer layer portion 8, the first molded product M <b> 1 with respect to the second main cavity 31 is inserted into the second main cavity 31 by inserting the first molded product M <b> 1 into the second main cavity 31. Installation ends.

  As shown in FIG. 10, in the second injection step, the second discharge port 34 is closed by a hydraulic cylinder or the like, and the second resin R <b> 2 is injected into the second main cavity 31. Examples of the second resin R2 injected into the second main cavity 31 include polyamide (PA), aromatic polyamide resin, ethylene-tetrafluoroethylene copolymer (ETFE), polyphenylene sulfide (PPS) having high heat resistance and high strength. Polypropylene (PP) or the like can be used. One or more gates (not shown) communicating with the second main cavity 31 are formed in the second mold part 20b, and the second resin R2 heated and melted from the gate to the second main cavity 31 is injected. To do. At this time, since the outer peripheral surface of the outer layer portion 8 is in contact with the peripheral wall surface 31a of the second main cavity 31, in the second injection fixation, the second resin R2 is used as the inner peripheral surface of the outer layer portion 8 in the second main cavity 31. Inject into the side space. Then, the space on the inner peripheral surface side of the outer layer portion 8 in the second main cavity 31 is filled with the second resin R2.

  In the second core moving step, the second discharge port 34 is opened by a hydraulic cylinder or the like. Then, as shown in FIG. 11, the second pressurized fluid is press-fitted from the second pressurized port 32, and the second floating core 36 is moved from the second pressurized port 32 toward the second discharge port 34. . That is, when the second pressurized fluid is pressed into the second main cavity 31 from the second pressurized port 32, the second floating core 36 provided in the second pressurized port 32 is pressed by the second pressurized fluid. Accordingly, the second main cavity 31 moves from the second pressurization port 32 toward the second discharge port 34 along the axis L31. As the second pressurized fluid that is press-fitted from the second pressurized port 32, the same fluid as the pressurized fluid that is press-fitted from the pressurized port 12 in the first embodiment can be used. And the 2nd resin R2 is discharged | emitted from the 2nd discharge port 34 by moving the 2nd floating core 36 in this way. Thereby, the inner peripheral surface of the inner layer portion 9 is formed. Further, the second floating core 36 is pressed against the inner peripheral surface 37 a of the second stopper 37 by moving the second floating core 36 in this way. Then, the second resin R2 remaining in the second main cavity 31 and the second resin R2 discharged from the second main cavity 31 to the second subcavity 35 are cut or almost cut.

  In the second extraction step, the second molded product M2 of the second resin R2 is extracted from the second main cavity 31 by a hydraulic arm or the like. At this time, the second resin R2 remaining in the second main cavity 31 and the second resin R2 discharged from the second main cavity 31 to the second subcavity 35 are cut or almost cut off. . For this reason, by removing the second molded product M2 from the second main cavity 31, the molded product from which the portion discharged from the second main cavity 31 to the second subcavity 35 has been removed, that is, the inner layer side of the outer layer portion 8 is removed. The inner layer portion 9 laminated on the substrate is obtained. Thereby, shaping | molding of 1 A of tubular hollow bodies is complete | finished.

  As described above, in the tubular hollow body molding die 20 and the tubular hollow body molding method according to the present embodiment, after the first resin R1 is injected into the first main cavity 21, the first pressurization port 22 performs the first pressurization. When the fluid is press-fitted, the first resin R1 is discharged from the first discharge port 24, and the first floating core 26 moves through the first main cavity 21 and is pressed against the inner peripheral surface 27a of the first stopper 27. Thereby, the first resin R1 remaining in the first main cavity 21 and the first resin R1 discharged from the first main cavity 21 are cut or almost cut. For this reason, by taking out the first molded product M1 of the first resin R1 from the first main cavity 21, it is possible to obtain the molded product from which the portion discharged from the first main cavity 21 is removed, that is, the outer layer portion 8. it can. Then, after the first molded product M1 taken out from the first main cavity 21 is installed in the second main cavity 31, and the second resin R2 is injected into the second main cavity 31, the second pressure port 32 is used to When the pressurized fluid is press-fitted, the second resin R2 is discharged from the second discharge port 34, and the second floating core 36 moves through the second main cavity 31 and is pressed against the inner peripheral surface 37a of the second stopper 37. . Thereby, the second resin R2 remaining in the second main cavity 31 and the second resin R2 discharged from the second main cavity 31 are cut or almost cut. For this reason, by removing the second molded product M2 of the second resin R2 from the second main cavity 31, the molded product from which the portion discharged from the second main cavity 31 has been removed, that is, on the inner layer side of the outer layer portion 8 is used. The laminated inner layer portion 9 can be obtained. As described above, since it is not necessary to separately provide a step of cutting the portion discharged from the first main cavity 21 and a step of cutting the portion discharged from the second main cavity 31, it is possible to reduce the number of steps.

  Further, since the outer peripheral surface 27 b of the first stopper 27 is separated from the peripheral wall surface 21 a of the first main cavity 21, the end of the outer layer portion 8 on the first discharge port 24 side is the peripheral wall surface of the first main cavity 21. 21a and the outer peripheral surface 27b of the first stopper 27 are formed. For this reason, regardless of the positional relationship between the first floating core 26 and the first stopper 27, the end portion on the first discharge port 24 side of the outer layer portion 8 can be formed with high accuracy. Similarly, since the outer peripheral surface 37 b of the second stopper 37 is separated from the peripheral wall surface 31 a of the second main cavity 31, the end of the inner layer portion 9 on the second discharge port 34 side is the periphery of the second main cavity 31. It is formed by the wall surface 31 a and the outer peripheral surface 37 b of the second stopper 37. For this reason, regardless of the positional relationship between the second floating core 36 and the second stopper 37, the end portion of the inner layer portion 9 on the second discharge port 34 side can be formed with high accuracy.

  Further, since the outer diameter of the first stopper 27 is larger than the outer diameter of the first floating core 26, after the first floating core 26 is pressed against the inner peripheral surface 27 a of the first stopper 27, It becomes easy to take out the first molded product M1 of one resin R1. Similarly, since the outer diameter of the second stopper 37 is larger than the outer diameter of the second floating core 36, after the second floating core 36 is pressed against the inner peripheral surface 37 a of the second stopper 37, It becomes easy to take out the second molded product M2 of the second resin R2.

  By the way, when the tubular hollow body 1A is formed by the tubular hollow body forming die 20, the inner peripheral surface of the end portion of the inner layer portion 9 is formed by the outer peripheral surface of the second stopper 37, and the remaining portion of the inner layer portion 9 is formed. The inner peripheral surface is formed by the outer peripheral surface of the second floating core 36. Since the outer diameter of the second stopper 37 is larger than the outer diameter of the second floating core 36, the inner diameter of the end portion of the inner layer portion 9 is larger than the inner diameter of the remaining portion of the inner layer portion 9. Thereby, when the inner layer portion 9 is the innermost layer of the tubular hollow body 1A, a step can be provided on the inner peripheral surface 5 of the tubular hollow body 1A, so that a connecting member (not shown) is inserted into the tubular hollow body 1A. In this case, the connecting member can be positioned with high accuracy.

  In addition, since the tubular hollow body 1A according to the present embodiment has a multilayer structure including the outer layer portion 8 and the inner layer portion 9, the resin of each layer can be made different from each other. Thereby, each layer can have various properties.

[Third embodiment]
Next, a third embodiment will be described.

  The tubular hollow body according to the third embodiment is basically the same as the tubular hollow body 1A according to the second embodiment, but a recess is formed on the inner peripheral surface of the outer layer portion and the outer peripheral surface of the inner layer portion. The difference from the tubular hollow body 1 </ b> A according to the second embodiment is that only a convex portion that enters the concave portion is formed.

  As shown in FIG. 12A, the tubular hollow body molding die 40 according to the third embodiment is basically the same as the tubular hollow body molding die 20 according to the second embodiment. The second floating core 46 corresponding to the second floating core 36 of the molding die 20 includes a convex portion 46a protruding from the outer peripheral surface.

  As shown in FIGS. 12A and 12B, the convex portion 46a moves in the first main cavity 21 in the first core moving step, so that the inner peripheral surface of the first molded product M1 (outer layer portion 8). In addition, a groove-like recess M1a extending along the axis L21 of the first main cavity 21 is formed. In addition, if the convex part 46a can form the recessed part M1a in the internal peripheral surface of the 1st molded product M1, the number, a shape, arrangement | positioning, etc. will not be specifically limited, It can set suitably.

  Thus, in this embodiment, the convex part 46a protrudes from the outer peripheral surface of the second floating core 46. For this reason, as shown to Fig.12 (a)-(c), the recessed part M1a corresponding to the convex part 46a is shape | molded in the internal peripheral surface of the 1st molded product M1 used as the outer layer part 8, and a 1st shaping | molding process is carried out. In the subsequent second molding step, the second resin R2 enters the concave portion M1a. Thereby, since the outer layer part 8 and the inner layer part 9 are couple | bonded by an uneven structure, the coupling strength of the outer layer part 8 and the inner layer part 9 can be improved.

[Fourth embodiment]
Next, a fourth embodiment will be described.

  The tubular hollow body according to the fourth embodiment is basically the same as the tubular hollow body 1A according to the second embodiment, except that convex portions are formed on the outer peripheral surface of the inner layer portion and the inner periphery of the outer layer portion. It differs from the tubular hollow body 1A according to the second embodiment only in that a recess into which the recess enters is formed on the surface. For this reason, below, only the matter which is different from the tubular hollow body 1A according to the second embodiment will be described, and description of the same matters as the tubular hollow body 1A according to the second embodiment will be omitted.

  As shown in FIG. 13, the tubular hollow body 1 </ b> C according to the present embodiment has a multilayer structure in which a plurality of resin layers are laminated, similarly to the tubular hollow body 1 </ b> A according to the second embodiment. In the present embodiment, the tubular hollow body 1C will be described as having a two-layer structure including an outer layer portion 8C and an inner layer portion 9C laminated on the inner layer side of the outer layer portion 8C. The outer layer portion 8 </ b> C is a layer corresponding to the outer layer portion 8, and the inner layer portion 9 </ b> C is a layer corresponding to the outer layer portion 8.

  The inner layer portion 9C includes a convex portion 9a protruding from the outer peripheral surface. The outer layer portion 8C includes a concave portion 8a that is recessed from the inner peripheral surface and into which the convex portion 9a enters. As a result, the outer layer portion 8C and the inner layer portion 9C are coupled together by a concavo-convex structure.

  The number, position, size, shape, and the like of the convex portions 9a and the concave portions 8a are not particularly limited. For example, as shown in FIGS. 13 and 14A to 14D, a plurality of (three in the drawing) convex portions 9a and concave portions 8a are formed in a plurality of cross sections in the direction of the axis L1 of the tubular hollow body 1C. May be. Further, the convex portion 9a may have a rectangular cross section as shown in FIG. 14A, or may have a reverse tapered shape as shown in FIG. 14B. ) And (d), the cross section may be tapered.

  Next, the tubular hollow body molding die 50 according to this embodiment will be described.

  As shown in FIG. 15, a tubular hollow body molding die 50 according to this embodiment forms a tubular hollow body 1C having a multilayer structure including an outer layer portion 8C and an inner layer portion 9C laminated on the inner layer side of the outer layer portion 8C. It is a mold to do. The tubular hollow body molding die 50 is a mold for molding the outer layer portion 8C after the inner layer portion 9C is molded, unlike the tubular hollow body molding die 20 according to the second embodiment. The tubular hollow body molding die 50 includes a first mold portion 50a for molding the outer layer portion 8C by injection molding, and an inner layer portion 9C by a fluid assist molding method similar to the tubular hollow body molding die 10 of the first embodiment. And a second mold part 50b for forming the mold. In the present embodiment, the first mold part 50a and the second mold part 50b are described as being integrally formed. However, the first mold part 50a and the second mold part 50b are formed separately. It may be.

  The first mold part 50 a includes a first main cavity 51, one end side opening / closing mold 52, and the other end side opening / closing mold 53.

  The first main cavity 51 is a cavity in which the first resin is injected in the shape of the outer peripheral surface of the outer layer portion 8C (the outer peripheral surface 4 of the tubular hollow body 1C). The one end side opening / closing mold 52 is a mold for opening and closing an end face on one end side of the first main cavity 51. The other end opening / closing mold 53 is a mold that opens and closes the end face on the other end side of the first main cavity 51.

  The second mold part 50b includes a second main cavity 61, a second pressure port 62, a second injector 63, a second discharge port 64, a second sub cavity 65, a second floating core 66, a first Two stoppers 67.

  The second main cavity 61 is a cavity in which the second resin is injected in the shape of the outer peripheral surface of the inner layer portion 9C. The second main cavity 61 includes a recess 61b that is recessed by the thickness of the outer layer portion 8C. The concave portion 61b forms the convex portion 9a of the inner layer portion 9C. For this reason, the recessed part 61b is formed in the position corresponding to the convex part 9a provided in the inner layer part 9C. The second pressurization port 62 is a port that is formed at one end of the second main cavity 61 and into which the second pressurization fluid is press-fitted into the second main cavity 61. The second injector 63 is an injection device that communicates with the second pressurization port 62 and injects the second pressurization fluid. The second discharge port 64 is formed at the other end of the second main cavity 61 and discharges the second resin from the second main cavity 61. The second sub cavity 65 is a cavity communicated with the first discharge port 54 and stores the second resin discharged from the second discharge port 64.

  The second floating core 66 is detachably provided on the second pressure port 62. The second floating core 66 is provided in the second main cavity 61 with the second pressurization port 62 as the back so as to be pressed by the second pressurization fluid press-fitted from the second pressurization port 62. . The maximum diameter of the second floating core 66 is substantially the same as the inner diameter of the inner layer portion 9C. The shape of the outer peripheral surface of the second floating core 66 is not particularly limited, and may be a shell shape, a conical shape, a hemispherical shape, a spherical shape, or the like. In the present embodiment, the outer peripheral surface of the second floating core 66 will be described as having a conical shape with the leading end rounded and the trailing end having the maximum diameter.

  The second stopper 67 is formed in a cylindrical shape having the axis L61 of the second main cavity 61 as the central axis. The second stopper 67 extends from the second discharge port 64 toward the second pressure port 62 along the axis L61 of the second main cavity 61. The second discharge port 64 is formed on the inner peripheral surface 67 a side of the second stopper 67. For this reason, the second resin injected into the second main cavity 61 is discharged from the second discharge port 64 only through the inner peripheral surface 67 a side of the second stopper 67.

  The inner peripheral surface 67 a of the second stopper 67 is formed in a conical shape (funnel shape) whose diameter is increased toward the second pressure port 62. The minimum inner diameter of the inner peripheral surface 67 a of the second stopper 67 is smaller than the maximum diameter of the second floating core 66. For this reason, when the second floating core 66 moves through the second main cavity 61 due to the pressurization of the second pressurized fluid from the second pressure port 62, the second floating core 66 moves into the second stopper 67. It is pressed against the peripheral surface 67a. In addition, it is preferable that the 2nd floating core 66 is pressed on the internal peripheral surface 67a of the 2nd stopper 67 in the perimeter. When the inner peripheral surface 67a of the second stopper 67 and the outer peripheral surface of the second floating core 66 are conical, the apex angle θ8 of the inner peripheral surface 67a of the second stopper 67 is the apex of the outer peripheral surface of the second floating core 66. It is preferably substantially the same as the angle θ7 or slightly smaller than the apex angle θ7 of the outer peripheral surface of the second floating core 66.

  The outer peripheral surface 67b of the second stopper 67 has the same diameter over the entire region in the direction of the axis L61 of the second main cavity 61. The outer diameter of the second stopper 67 is larger than the outer diameter of the second floating core 66. Further, the outer peripheral surface 67 b of the second stopper 67 is separated from the peripheral wall surface 61 a of the second main cavity 61. Therefore, the second main cavity 61 has a space for the injected second resin to enter between the peripheral wall surface 61 a of the second main cavity 61 and the outer peripheral surface 67 b of the second stopper 67. The peripheral wall surface 61a of the second main cavity 61 refers to a wall surface having a circular cross section with which the outer peripheral surface of the outer layer portion 8C comes into contact.

  Next, the tubular hollow body forming method according to the present embodiment will be described.

  The tubular hollow body forming method according to this embodiment uses a tubular hollow body forming die 50 to form a multilayer hollow tubular body 1C having an outer layer portion 8C and an inner layer portion 9C laminated on the inner layer side of the outer layer portion 8C. This is a method of molding.

  This tubular hollow body forming method includes a second forming step for forming the inner layer portion 9C and a first forming step for forming the outer layer portion 8C after the second forming step.

  In the second molding step, first, the second injection step is performed, then the second core moving step is performed, and then the second extraction step is performed.

  As shown in FIG. 16, in the second injection step, the second discharge port 64 is closed by a hydraulic cylinder or the like, and the second resin R <b> 4 is injected into the second main cavity 61. The second resin R4 injected into the second main cavity 61 can be the same resin as the second resin R2 injected into the second main cavity 31 in the second embodiment. One or more gates (not shown) communicating with the second main cavity 61 are formed in the second mold part 50b, and the second resin R4 heated and melted is injected into the second main cavity 61 from the gate. To do. Then, the second main cavity 61 is filled with the second resin R4. The concave portion 61b of the second main cavity 61 is also filled with the second resin R4.

  In the second core moving step, the second discharge port 64 is opened by a hydraulic cylinder or the like. Then, as shown in FIG. 17, the second pressurized fluid is press-fitted from the second pressurized port 62, and the second floating core 66 is moved from the second pressurized port 62 toward the second discharge port 64 side. . That is, when the second pressurized fluid is pressed into the second main cavity 61 from the second pressurized port 62, the second floating core 66 provided in the second pressurized port 62 is pressed by the second pressurized fluid. Thus, the second main cavity 61 moves from the second pressure port 62 toward the second discharge port 64 along the axis L61. The second pressurized fluid that is press-fitted from the second pressurized port 62 can be the same fluid as the pressurized fluid that is press-fitted from the pressurized port 12 in the first embodiment. And the 2nd resin R4 is discharged | emitted from the 2nd discharge port 64 by moving the 2nd floating core 66 in this way. Thereby, the inner peripheral surface of the inner layer portion 9C is formed. Further, the second floating core 66 is pressed against the inner peripheral surface 67 a of the second stopper 67 by moving the second floating core 66 in this way. Then, the second resin R4 remaining in the second main cavity 61 and the second resin R4 discharged from the second main cavity 61 to the second subcavity 65 are cut or almost cut.

  In the second extraction step, the second molded product M4 of the second resin R4 is extracted from the second main cavity 61 by a hydraulic arm or the like. At this time, the second resin R4 remaining in the second main cavity 61 and the second resin R4 discharged from the second main cavity 61 to the second subcavity 65 are cut or almost cut off. . For this reason, by removing the second molded product M4 from the second main cavity 61, a molded product from which the portion discharged from the second main cavity 61 to the second sub-cavity 65 is removed, that is, the inner layer portion 9C is obtained. . Note that the portion discharged from the second subcavity 65 to the second subcavity 65 and the second floating core 66 are taken out at an arbitrary timing.

  In the first molding process, first, an installation process is performed, then a first injection process is performed, and then a first extraction process is performed.

  As shown in FIG. 18, in the installation process, the one end side opening / closing mold 52 and the other end side opening / closing mold 53 are opened by a hydraulic cylinder or the like, and the second molded product M <b> 4 taken out in the second extraction process is made into the first main cavity 51. Install. At this time, since the convex portion 9a protruding by the thickness of the outer layer portion 8C is formed on the outer peripheral surface of the second molded product M4 to be the inner layer portion 9C, the second molded product M4 is moved to the second main cavity 61. Then, the second molded product M4 is positioned with respect to the second main cavity 61 by the convex portion 9a. In addition, it is preferable to set the number, position, size, shape, and the like of the convex portion 9a to such an extent that the second molded product M4 can be positioned with respect to the second main cavity 61. Thereby, the installation of the second molded product M4 with respect to the second main cavity 61 is completed.

  As shown in FIG. 19, in the first injection step, the one end side opening / closing mold 52 and the other end side opening / closing mold 53 are closed by a hydraulic cylinder or the like, and the first resin R <b> 3 is injected into the first main cavity 51. The first resin R3 injected into the first main cavity 51 can be the same resin as the first resin R1 injected into the first main cavity 21 in the second embodiment. One or more gates (not shown) communicating with the first main cavity 51 are formed in the first mold part 50a, and the first resin R3 heated and melted is injected into the first main cavity 51 from the gate. To do. At this time, the first resin R3 is injected into the space on the outer peripheral surface side of the inner layer portion 9C in the first main cavity 51. Then, the first resin R3 fills the space on the outer peripheral surface side of the inner layer portion 9C in the first main cavity 51 and surrounds the convex portion 9a of the inner layer portion 9C.

  In the first removal step, the one end side opening / closing mold 52 and the other end side opening / closing mold 53 are opened by a hydraulic arm or the like. Then, the first molded product M3 of the first resin R3 is taken out from the first main cavity 51 by a hydraulic arm or the like. Thereby, the outer layer part 8C laminated | stacked on the outer peripheral surface side of the inner layer part 9C is obtained. Thereby, shaping | molding of the tubular hollow body 1C is complete | finished.

  Thus, in the tubular hollow body molding die 50 and the tubular hollow body molding method according to the present embodiment, after the second resin R4 is injected into the second main cavity 61, the second pressurization port 62 is used for the second pressurization. When the fluid is press-fitted, the second resin R4 is discharged from the second discharge port 64, and the second floating core 66 moves through the second main cavity 61 and is pressed against the inner peripheral surface 67a of the second stopper 67. Accordingly, the second resin R4 remaining in the second main cavity 61 and the second resin R4 discharged from the second main cavity 61 are cut or almost cut. For this reason, by taking out the second molded product M4 of the second resin R4 from the second main cavity 61, a molded product from which the portion discharged from the second main cavity 61 is removed, that is, the inner layer portion 9C can be obtained. it can. Then, the second molded product M4 taken out from the second main cavity 61 is installed in the first main cavity 51, the first resin R3 is injected into the first main cavity 51, and the first resin R3 is injected from the first main cavity 51. By taking out the first molded product M3, the inner layer portion 9C laminated on the inner layer side of the outer layer portion 8C can be obtained. As described above, since it is not necessary to provide a separate step for cutting the portion discharged from the second main cavity 61, the number of man-hours can be reduced.

  Further, since the outer peripheral surface 67 b of the second stopper 67 is separated from the peripheral wall surface 61 a of the second main cavity 61, the end portion on the second discharge port 64 side of the inner layer portion 9 C is the peripheral wall surface of the second main cavity 61. It is formed by 61 a and the outer peripheral surface 67 b of the second stopper 67. For this reason, regardless of the positional relationship between the second floating core 66 and the second stopper 67, the end portion on the second discharge port 64 side of the inner layer portion 9C can be formed with high accuracy.

  In addition, since the outer diameter of the second stopper 67 is larger than the outer diameter of the second floating core 66, the second floating core 66 is pressed against the inner peripheral surface 67 a of the second stopper 67, and then is It becomes easy to take out the second molded product M4 of the two resins R4.

  By the way, when the tubular hollow body 1C is formed by the tubular hollow body forming die 50, the inner peripheral surface of the end portion of the inner layer portion 9C is formed by the outer peripheral surface 67b of the second stopper 67, and the remaining portion of the inner layer portion 9C. The inner peripheral surface is formed by the outer peripheral surface of the second floating core 66. Since the outer diameter of the second stopper 67 is larger than the outer diameter of the second floating core 66, the inner diameter of the end portion of the inner layer portion 9C is larger than the inner diameter of the remaining portion of the inner layer portion 9C. Thereby, when the inner layer portion 9C is the innermost layer of the tubular hollow body, a step can be provided on the inner peripheral surface 5 of the tubular hollow body 1C. The member can be positioned with high accuracy.

  Moreover, since the recessed part 61b is formed in the 2nd main cavity 61, the convex part 9a corresponding to the recessed part 61b is formed in the outer peripheral surface of the 2nd molded product M4 used as the inner layer part 9C, and follows a 2nd shaping | molding process. In the first molding step, the first resin R3 surrounds the convex portion 9a. As a result, the outer layer portion 8C and the inner layer portion 9C are bonded by the concavo-convex structure, so that the bonding strength between the outer layer portion 8C and the inner layer portion 9C can be improved.

  Moreover, since the concave portion 61b is depressed by the thickness of the outer layer portion 8C, the inner layer portion 9C when the inner layer portion 9C is installed in the first main cavity 51 by the convex portion formed on the outer peripheral surface of the inner layer portion 9C. Can be positioned.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment.

  For example, in the above embodiment, the outer peripheral surface of each stopper has been described as being separated from the peripheral wall surface of each main cavity, but if there is no problem with the molding accuracy of the end of each molded product, the outer peripheral surface of each stopper is You may contact | abut to the surrounding wall surface of each main cavity.

  In the above embodiment, the outer diameter of each stopper is described as being larger than the outer diameter of each floating core. However, when the step does not have to be formed on the inner peripheral surface of the tubular hollow body, both outer diameters are used. May be the same.

  Moreover, in the said embodiment, although the cross-sectional shape of each tubular hollow body, each main cavity, each floating core, and each stopper was demonstrated as circular, these cross-sectional shapes are not limited to circular. For example, an ellipse or a polygon may be used.

  Moreover, in 2nd-4th embodiment, although demonstrated as what is a multilayer structure in the whole region of a tubular hollow body, it is good also considering a part of tubular hollow body of a multilayer structure as a single layer structure. For example, as shown in FIG. 20, in the tubular hollow body 1D having a multilayer structure in which the inner layer portion 72 is laminated on the inner layer side of the outer layer portion 71, one connection end portion 73 connected to another member such as a connection member and the other The connecting end portion 74 may have a single layer structure including only the inner layer portion 72.

  In the fourth embodiment, the concave portion 61b is formed in the second main cavity 61 to form the convex portion 9a on the inner layer portion 9C. However, the bonding strength between the outer layer portion 8C and the inner layer portion 9C is increased. If the inner layer portion 9C can be positioned with respect to the first main cavity 51 by, for example, arranging another member in the first main cavity 51, the recess 61b is not formed in the second main cavity 61. Alternatively, the convex portion 9a may not be formed on the inner layer portion 9C.

  DESCRIPTION OF SYMBOLS 1,1A, 1C, 1D ... Tubular hollow body, 2 ... One end, 3 ... Other end, 4 ... Outer peripheral surface, 5 ... Inner peripheral surface, 5a ... First inner peripheral surface portion, 5b ... Second inner peripheral surface portion, 6 ... Bending part, 7 ... fixing plate part, 8,8C ... outer layer part, 8a ... concave part, 9, 9C ... inner layer part, 9a ... convex part, 10 ... tubular hollow body molding die, 11 ... main cavity, 11a ... circumferential wall surface , 12 ... Pressure port, 13 ... Injector, 14 ... Discharge port, 15 ... Subcavity, 16 ... Floating core, 17 ... Stopper, 17a ... Inner peripheral surface, 17b ... Outer peripheral surface, 20 ... Tubular hollow body molding die, 20a ... 1st type | mold part, 20b ... 2nd type | mold part, 21 ... 1st main cavity, 21a ... Circumferential wall surface, 22 ... 1st pressurization port, 23 ... 1st injector, 24 ... 1st discharge port, 25 ... 1st One sub-cavity, 26 ... first floating core, 27 ... first stopper, 27a ... inner peripheral surface 27b ... outer peripheral surface, 31 ... second main cavity, 31a ... peripheral wall surface, 32 ... second pressurizing port, 33 ... second injector, 34 ... second outlet, 35 ... second subcavity, 36 ... second floating 37, second stopper, 37a, inner circumferential surface, 37b, outer circumferential surface, 40 ... tubular hollow body molding die, 46 ... second floating core, 46a ... convex portion, 50 ... tubular hollow body molding die, 50a ... first mold part, 50b ... second mold part, 51 ... first main cavity, 52 ... one end side opening / closing mold, 53 ... other end side opening / closing mold, 54 ... first discharge port, 61 ... second main cavity, 61a ... peripheral wall surface, 61b ... concave portion, 62 ... second pressure port, 63 ... second injector, 64 ... second discharge port, 65 ... second subcavity, 66 ... second floating core, 67 ... second stopper, 67a ... inner peripheral surface, 67b ... outer peripheral surface, DESCRIPTION OF SYMBOLS 1 ... Outer layer part, 72 ... Inner layer part, 73 ... Connection end part, 74 ... Connection end part, L1, L11, L21, L31, L61 ... Axis, M ... Molded article, M1, M3 ... First molded article, M1a ... Recess, M2, M4 ... second molded product, R ... resin, R1, R3 ... first resin, R2, R4 ... second resin, [theta] 1- [theta] 8 ... apex angle.

Claims (20)

A mold for forming a tubular hollow body for forming a tubular hollow body,
The shape of the outer peripheral surface of the tubular hollow body, the main cavity into which the resin is injected,
A pressurization port formed at one end of the main cavity and into which a pressurized fluid is press-fitted into the main cavity;
Formed at the other end of the main cavity, and a discharge port for discharging the resin from the main cavity;
A floating core detachably provided on the pressure port;
A cylindrical stopper extending from the discharge port toward the pressure port side along the axis of the main cavity,
The floating core is pressed against the inner peripheral surface of the stopper when the pressurized fluid is press-fitted from the pressurized port and the floating core moves through the main cavity;
Tubular hollow body mold. The outer peripheral surface of the stopper is separated from the peripheral wall surface of the main cavity.
The tubular hollow body mold according to claim 1. The outer diameter of the stopper is larger than the outer diameter of the floating core,
The tubular hollow body mold according to claim 2. A tubular hollow body molding die for molding a tubular hollow body having a multilayer structure comprising an outer layer part and an inner layer part laminated on the inner layer side of the outer layer part,
A first mold part for molding the outer layer part;
A second mold part for molding the inner layer part,
The first mold part is
Forming the shape of the outer peripheral surface of the outer layer portion, a first main cavity into which the first resin is injected,
A first pressurization port formed at one end of the first main cavity and press-fitting a first pressurization fluid into the first main cavity;
A first discharge port formed at the other end of the first main cavity for discharging the first resin from the first main cavity;
A first floating core detachably provided on the first pressure port;
A cylindrical first stopper extending from the first discharge port toward the first pressure port side along the axis of the first main cavity,
When the first pressurized fluid is press-fitted from the first pressurized port and the first floating core moves through the first main cavity, the first floating core is an inner peripheral surface of the first stopper. Pressed against
The second mold part is
Forming the shape of the outer peripheral surface of the outer layer portion, a second main cavity into which the second resin is injected, and formed at one end of the second main cavity to press-fit a second pressurized fluid into the second main cavity A second pressure port;
A second discharge port formed at the other end of the second main cavity for discharging the second resin from the second main cavity;
A second floating core formed to be smaller in diameter than the first floating core and detachably provided in the second pressure port;
A cylindrical second stopper extending from the second discharge port toward the second pressure port side along the axis of the second main cavity,
When the second pressurized core is press-fitted from the second pressurized port and the second floating core moves through the second main cavity, the second floating core becomes the inner peripheral surface of the second stopper. Pressed against,
Tubular hollow body mold. The outer peripheral surface of the first stopper is separated from the peripheral wall surface of the first main cavity,
The outer peripheral surface of the second stopper is separated from the peripheral wall surface of the second main cavity.
The tubular hollow body mold according to claim 4. The outer diameter of the first stopper is larger than the outer diameter of the first floating core,
The outer diameter of the second stopper is larger than the outer diameter of the second floating core,
The tubular hollow body mold according to claim 5. The first floating core includes a protrusion protruding from the outer peripheral surface,
The tubular hollow body molding die according to any one of claims 4 to 6. A tubular hollow body molding die for molding a tubular hollow body having a multilayer structure comprising an outer layer part and an inner layer part laminated on the inner layer side of the outer layer part,
A first mold part for molding the outer layer part;
A second mold part for molding the inner layer part,
The first mold part has a shape of the outer peripheral surface of the outer layer part, and includes a first main cavity into which a first resin is injected,
The second mold part is
Forming the shape of the outer peripheral surface of the inner layer portion, a second main cavity into which the second resin is injected,
A second pressurization port formed at one end of the second main cavity and press-fitting a second pressurization fluid into the second main cavity;
A second discharge port formed at the other end of the second main cavity for discharging the second resin from the second main cavity;
A second floating core detachably provided on the second pressure port;
A second stopper extending from the second discharge port toward the second pressure port side along the axis of the second main cavity,
When the second pressurized core is press-fitted from the second pressurized port and the second floating core moves through the second main cavity, the second floating core becomes the inner peripheral surface of the second stopper. Pressed against,
Tubular hollow body mold. The outer peripheral surface of the second stopper is separated from the peripheral wall surface of the second main cavity.
The tubular hollow body molding die according to claim 8. The outer diameter of the second stopper is larger than the outer diameter of the second floating core,
The tubular hollow body molding die according to claim 9. The second main cavity includes a recess that is recessed by the thickness of the outer layer portion.
The tubular hollow body molding die according to any one of claims 8 to 10. A tubular hollow body molding method for molding a tubular hollow body using the tubular hollow body molding die according to any one of claims 1 to 3,
An injection step of injecting resin into the main cavity;
Pressurizing fluid from the pressurizing port moves the floating core from the pressurizing port toward the discharge port, discharges the resin from the discharge port, and moves the floating core to the inside of the stopper. A core moving process to press against the peripheral surface;
An extraction step of taking out the molded product of the resin from the main cavity,
Tubular hollow body forming method. A tubular hollow body having a multilayer structure including an outer layer part and an inner layer part laminated on the inner layer side of the outer layer part is molded using the tubular hollow body molding die according to any one of claims 4 to 7. A tubular hollow body forming method comprising:
A first molding step of molding the outer layer portion;
A second molding step for molding the inner layer portion after the first molding step,
The first molding step includes
A first injection step of injecting a first resin into the first main cavity;
After the first injection step, the first floating core is moved from the first pressurization port toward the first discharge port by press-fitting the first pressurization fluid from the first pressurization port, A first core moving step of discharging the first resin from the first outlet and pressing the first floating core against the inner peripheral surface of the first stopper;
After the first core moving step, a first removal step of taking out the first molded product of the first resin from the first main cavity,
The second molding step includes
An installation step of installing the first molded product in the second main cavity;
A second injection step of injecting a second resin into the second main cavity after the installation step;
After the second injection step, the second floating core is moved from the second pressure port toward the second outlet side by press-fitting a second pressure fluid from the second pressure port, A second core moving step of discharging the second resin from the second discharge port and pressing the second floating core against the inner peripheral surface of the second stopper;
After the second core moving step, a second extraction step of taking out the second molded product of the second resin from the second main cavity,
Tubular hollow body forming method. In the first molding step, a recess is formed on the inner peripheral surface of the first molded product.
The tubular hollow body forming method according to claim 13. A tubular hollow body having a multilayer structure including an outer layer part and an inner layer part laminated on the inner layer side of the outer layer part is molded using the tubular hollow body molding die according to any one of claims 8 to 11. A tubular hollow body forming method comprising:
A second molding step for molding the inner layer portion;
A first molding step for molding the outer layer portion after the second molding step,
The second molding step includes
A second injection step of injecting a second resin into the second main cavity;
After the second injection step, the second pressurized core is pressed from the second pressurized port to move the second floating core from the second pressurized port toward the second outlet side. A second core moving step of discharging the second resin from the second discharge port and pressing the second floating core against the inner peripheral surface of the second stopper;
After the second core moving step, a second removal step of taking out the second molded product of the second resin from the second main cavity,
The first molding step includes
An installation step of installing the second molded article in the first main cavity;
A first injection step of injecting a first resin into the first main cavity after the installation step;
After the first injection step, a first removal step of taking out the first molded product of the first resin from the first main cavity,
Tubular hollow body forming method. In the second molding step, a convex portion protruding by the thickness of the outer layer portion is molded on the outer peripheral surface of the second molded product.
The tubular hollow body forming method according to claim 15. The first resin and the second resin are different from each other.
The method for forming a tubular hollow body according to any one of claims 13 to 16. A tubular hollow body made of resin,
The inner peripheral surface of at least one end of the tubular hollow body is:
A first inner peripheral surface portion;
A second inner peripheral surface portion extending from the first inner peripheral surface portion to the end surface of the tubular hollow body,
The inner diameter of the second inner peripheral surface portion is larger than the inner diameter of the first inner peripheral surface portion.
Tubular hollow body. The outer layer,
An inner layer portion laminated on the inner layer side of the outer layer portion,
The tubular hollow body according to claim 18. Two or more bent portions are provided along the axis of the tubular hollow body,
The tubular hollow body according to any one of claims 18 to 19.

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