CZ310085B6 - A stop mandrel for a mould for shaping plastic tubes or rubber hoses - Google Patents

Abstract

A stop mandrel (1) for a mould (2) for shaping plastic tubes (3) or rubber hoses, which includes a mounting part (14) for mounting the stop mandrel (1) on the mould (2), whereas the stop mandrel (1) contains a guide pin (11) for guiding a shaped tube (3) or hose on the stop mandrel (1), lies in the fact that the guide pin (11) is mounted in an axially spring-loaded reciprocatingly sliding way on the mounting part (14), whereas the mounting part (14) contains a bush (10) with a cavity (100), where the guide pin (11) is either mounted in an axially spring-loaded reciprocatingly sliding way in the cavity (100) of the bushing (10) or it is mounted in an spring-loaded reciprocatingly sliding way with its axial cavity (113) on the outside perimeter of the bushing (10).

Description

Stop mandrel for a mold for forming plastic pipes or rubber hoses

Field of technology

A stop mandrel weight for a mold for forming plastic pipes or rubber hoses is invented, which contains a bearing part for storing the stop mandrel on the mold, whereby the stop mandrel contains a guide pin for said shaped pipes or hoses to the stop mandrel.

Current state of the art

For bending plastic pipes or rubber hoses, hereinafter referred to as "pipes or hoses", forming molds made of mechanically and temperature-resistant material are used, into which a plastic pipe or rubber hose is pressed for shaping, which after passing through the furnace/steam forming process and after cooling, it retains the three-dimensional shape of the forming mold in which it was placed at the beginning of the process. An example of a forming mold can be, for example, a solution according to EP 3647018 A1. Even when a pipe or hose is inserted into a three-dimensional forming mold, bending, or even twisting or other stressing of the outgoing straight pipe or hose occurs. The actual insertion of the shaped pipe or hose into the forming mold is performed either manually or with the help of a machine device, known for example from EP 3650198 A1.

The actual insertion of the pipe or hose into the molding mold is carried out in such a way that the pipe or hose must first be positioned with respect to the front end of the molding mold, so that the pipe or hose is placed with its front end against the stop of the attached molding mold, which determines the length of this front end of the pipe or hose after inserting the entire length of pipe or hose into the forming mold. Currently, rigid (fixed) stops are used as stops, as shown, for example, in Fig. 0, which shows a fixed stop according to the state of the art. Such a fixed stop includes a bearing part 14 with a navadecim pin 11 and an axial end 111. The excessive stiffness of such a stop is, however, unsuitable for mechanically inserting a pipe or hose into a mold, for example using the device known from EP 3650198 A1, when the unequal length of the pipe or hose blank causes a different position the ends of the pipe or hose due to the form, thus leading to errors in the production of shaped pipes or hoses.

The aim of the invention is to eliminate or at least minimize the disadvantages of the current state of the art, i.e. in particular to reduce or eliminate errors in the positioning of pipes or hoses when they are mechanically inserted into a forming mold, which is currently caused by the non-uniform length of the formed pipes or hoses.

The essence of the invention

The aim of the invention is to insert a stop mandrel for shaping plastic pipes or rubber hoses, the essence of which is that the guide pin is mounted on the bearing part in an axially spring-loaded reciprocating manner, whereby the bearing part contains a housing with a cavity, where the guide pin is axially spring-loaded in a reciprocating manner housed in the housing cavity or is spring-loaded and reciprocatingly housed by its axial cavity on the outer circumference of the housing.

Such a stop mandrel makes it possible to effectively and efficiently eliminate the disadvantages of the state of the art, especially errors in laying pipes or hoses due to the uneven length of individual pipes or hoses. Another advantage of this solution is that when using the system of pushing the pipe or hose to this flexible stop, the pipe or hose does not move from the zero point when the pipe or hose is inserted into the forming mold by the automatic device and enables smoother operation of the automatic device for inserting pipes or hoses into the molding forms. Another advantage is that when starting to install a plastic pipe or rubber hose, the load on the installer is reduced.

- 1 CZ 310085 B6 robot, or the load on the mechanisms of this robot is reduced, because if the length tolerance of the pipe or hose were too "plus", the robot would push itself into the sprung stop with an unnecessarily large force (the so-called "hard force") and could, as a result of its protection against pressure and turn off. A flexible stop according to this solution for this barrier.

In order to improve the guidance of the guide pin on the pipe or hose, it is convenient if the guide pin is placed in or on the housing with its rear end and at its front end is provided with a fitting that is adapted to fit the front end of the pipe or hose.

For the improvement of the guided pipe or hose on the guide pin, it is advantageous if, before fitting, an axle end protrudes from the guide pin, which is adjusted for the defined insertion and guidance of the front end of the pipe or hose and on the fitting.

From a design, production and operational point of view, it is advantageous if a compression coil spring or at least one Thaler spring is placed in the cavity of the housing, which rests with its front end on the rear end of the guide flail and with its rear end rests on the rear of the housing.

At the same time, a coil spring or plate spring is also suitable for guiding the guide pin, if the compression coil spring or plate spring is mounted on an axial pin, which has its rear end of the axle located in the rear cell of the housing and its front end reaches into the cavity in the guide pin .

To limit mutual movements, it is convenient if the housing is equipped with a longitudinal groove through which a radial pin located in the navadecim pin passes.

Clarification of drawings

The invention is shown schematically in the drawing, where Fig. 0 shows a stop mandrel according to the current state of the art, Fig. 1 a stop mandrel according to this invention - longitudinal section, Fig. 2 a first example of the realization of a forming mold for use with a stop mandrel according to this invention and Fig. 3 second example of the implementation of a forming mold for use with a stop mandrel according to this invention.

Examples of the implementation of the invention

The invention will be described on examples of the design of a stop mandrel 1 for use with a molding mold 2 for the machine introduction of plastic pipes or rubber hoses into the molding mold 2 and an example of the design of a pair of molding molds 2 usable with this stop mandrel 1.

The stop mandrel 1 is essentially an axially sprung unit, i.e. it is provided with an axially sprung navadecim pin 11, which is provided with a fitting 110 at its front end, which is designed to fit against the front wall 30 of the front end of the pipe 3 or hose.

In the illustrated embodiment, the stop mandrel 1 contains a housing 10, which is adapted to be placed on the forming mold 2 (indicated by dashed lines in Fig. 1) or is adapted for a defined fixed placement with respect to the front end of the forming mold 2, etc. The housing 10 is thus a part of the bearing part 14 for storing the stop mandrel 1 on the form 2 or about the form 2.

In the cavity 100 of the housing 10, a guide pin 11 is mounted with its rear end of the spring reciprocatingly displaceable in the direction of the longitudinal axis O of the stop mandrel 1. The guide pin 11 is provided with a fitting 110 at its front end, which is adapted to abut the front wall 30 of the front end of the pipe 3 or hose. Before mounting 110, an axial end 111 protrudes from the guide pin 11, which is

- 2 CZ 310085 B6 adapted for the defined insertion and guidance of the front end of the pipe 3 or hose and on the fitting 110.

In the illustrated embodiment, the cavity 100 of the housing 10 houses a compressive coil spring 12, or an unillustrated plate spring or a set of plate springs, etc., which rests with its front end 120 on the rear end 112 of the drive pin 11. The coil spring is pressed with its rear end 121 12 rests on the rear cell 101 of the housing 10. In the illustrated embodiment, the compression coiled spring 12 is mounted on the axial pin 13, which is located with its rear end of the axis in the rear cell 101 of the housing 10 and with its front end extends into the cavity 113 in the navadecim pin 11 , which improves not only the rigidity of the entire assembly, but also the axial guidance of the spring 12 and the guide pin 11.

To define the length tolerance of pipes 3 or hoses, the housing 10 is equipped with a longitudinal slot 101, which is traversed by a radial pin 114 located in the guide pin 11. The radial pin 114 and the longitudinal slot 101 prevent the guide pin 11 from being accidentally removed from the housing 10 and define the so-called zero point, which is described in more detail in the next text. Together with the length of the longitudinal groove 101, the radial pin 114 limits the elastic stroke, which prevents the full compression of the spring 12 when inserting the pipe or hose.

The molding mold 2 of pipes 3 or hoses, in the example of the embodiment in Fig. 2, contains a clamping part 20 for the stop mandrel 1, where this clamping part 20 is integrated directly into the molding mold 2. In the embodiment in Fig. 3, the molding mold 2 is supported by arms 210 on the holder 21, through which the clamping part 20 for the stop mandrel 1 is also placed on the holder 21, here also with the help of the arms 210. In the embodiment not shown, the stop mandrel 1 is placed on the forming mold 2 in another suitable way, whereby integral parts of the forming body can also be forms 2.

In the non-illustrated embodiment, the guide pin 11 is spring-loaded and reversibly slidably supported by its axial cavity on the outer circumference of the sleeve 10, i.e. the sleeve 10 is arranged in the axial cavity 113 of the guide pin 11.

According to the invention, the stop mandrel 1 works in such a way that the device (not shown) for the mechanical introduction of the pipe 3 or the hose into the forming mold 2 guides the pipe 3 or the hose with its front end to the axial end 111 of the guide pin 11. The guide pin 11 can move along the guided pipe 3 or the hose in frames of the holder 101 and the radial flail 114 within a given tolerance given by the difference in the diameter of the radial flail 114 and the length of the holder 101. This compensates for the length tolerance of the pipe 3 or the hose and at the same time prevents collisions and excessive loading of both the device for machine installation of the pipe 3 or the hose and molding mold 2. After placing the pipe 3 or hose on the axial end 111 of the guide pin 11 and using the spring tolerance between the diameter of the radial pin 114 and the length of the slot 101, the pipe 3 or the hose is inserted by the device into the molding mold 2 and in the first phase of the device displacement, to move back the guide pin 11 to the zero (initial) position and to set the customs wall 30 of the front end of the pipe 3 or hose to the initial (zero) position. According to the needs of the particular technology, the material of the pipe 3 or hose, temperatures, etc., the pipe 3 or hose is now either fixed (clamped) in this zero position or left free, if the technology allows it and there is no danger of the front end of the pipe 3 or hose moving spontaneously, and arranged to completely insert the pipe 3 or hose along its entire length into the forming mold 2.

Industrial usability

The invention is particularly useful for the mechanical insertion of plastic pipes or rubber hoses into molding forms, such as labyrinths and similar 3D molding machines.

Claims (6)

1. Stop mandrel (1) for mold (2) for forming plastic pipes (3) or rubber hoses, which contains a bearing part (14) for placing the stop mandrel (1) on the mold (2), whereby the stop mandrel (1) contains guide pin (11) for said shaped pipes (3) or hoses on a stop mandrel (1), characterized by the fact that the guide pin (11) is mounted on the bearing part (14) in an axially spring-loaded reciprocating manner, through the bearing part (14) contains a housing (10) with a cavity (100), where the guide pin (11): - it is either axially sprung reversibly slidably housed in the cavity (100) of the housing (10); - or the suspension is reciprocatingly supported by its axial cavity (113) on the outer circumference of the housing (10). 2. The stop mandrel (1) according to claim 1, characterized in that the guide pin (11) is located in or on the housing (10) at its rear end, and that at its front end it is provided with a fitting (110) which is adapted for fitting the front wall (30) of the front end of the pipe (3) or hose. 3. The stop mandrel (1) according to claim 2, characterized by the fact that before the mounting (110) an axial end (111) extends from the guide pin (11), which is adapted for the defined insertion and guidance of the front end of the pipe (3) or hose and on the fitting (110). 4. Stop pin (1) according to any of the preceding claims, characterized by the fact that in the cavity (100) of the housing (10) a compressive coil spring (12) or at least one plate spring, which is supported by its front end (120), is placed it rests on the rear end (112) of the guide flail (11) and its rear end (121) on the rear whole (101) of the case (10). 5. Stop mandrel (1) according to claim 4, characterized by the fact that the pressure coil spring (12) or plate spring is mounted on the axial pin (13), which is located with its rear end of the axis in the rear cell (101) of the housing (10) ) and with its front end reaches into the cavity (113) in the navadecim flail (11). 6. Stop mandrel (1) according to any one of the preceding claims, characterized in that the housing (10) is provided with a longitudinal groove (101) through which the radial pin (114) located in the navadecim pin (11) passes.