JPH0669568U - Pipe connection structure - Google Patents

Abstract

(57) [Abstract] [Purpose] Generally, the safety of the fluid pipe can be ensured even when the pulling force acts on the receiving pipe and the inserting pipe and when the compressive force acts on the both pipes. Provided is a pipe connection structure capable of ensuring the safety of a fluid pipe when the pulling force acts even under the condition that the protection ring is displaced in the radial contraction direction and easily slips into the inner peripheral side of the pullout blocking ring. Structure: The inner peripheral surface of the ring 6 is guided so as to translate the protection ring 6 (the ring that protects the seal ring 7) in the axial direction of the tube in parallel with the compression force and the extraction force. The fin-shaped guide portion 5d is inserted into the insertion tube 3 and extends in the tube axis direction.
It is provided on the end face of the pull-out prevention ring 5 on the base end side of the insertion tube 3.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pipe connection structure used when connecting fluid pipes such as water pipes and gas pipes in a watertight and airtight state.

[0002]

[Prior art]

 It is possible to secure the safety of the fluid pipe when a pulling force above a certain level is applied to both pipes connected using such a pipe connection structure due to landslides, uneven settlement, etc. As a pipe connection structure capable of ensuring the safety of the fluid pipe when a certain amount of axial compressive force is applied to both pipes due to the above, the inventors of the present invention have previously shown in FIG. Is developing.

The pipe connection structure is specifically configured as described below. That is, on the outer peripheral surface near the tip of the insertion pipe 3 fitted in the taper pipe portion 1 in the receiving pipe 2 having the taper pipe portion 1 having an outward expansion at the end, in the pipe axis direction. The annular groove 4 having an appropriate groove width is formed so as to have a constant groove depth in the tube axis direction. In the vicinity of the base end side of the position where the annular groove 4 is formed in the insertion tube 3, the pressing force from the base end side of the insertion tube 3 (specifically, the flange portion 1A provided in the tapered pipe portion 1 The sealing ring 7 (which seals between the two pipes 2 and 3) based on the pressing force of the push ring 9 that is moved toward the distal end side of the insertion pipe 3 by the bolt 10 that is fastened with a nut while the head is locked to For example, a protective ring 6 (for example, a rubber-impregnated fibrous body) for protecting a rubber annular gasket or the like from the distal end side of the insertion tube 3 is externally positioned. The annular groove 4 has a width smaller than the groove width, and when the both tubes 2 and 3 relatively move in the drawing direction by a certain amount or more, the annular groove 4 is rigidly attached to the one axial end face 4a of the annular groove 4. A steel C-shaped pull-out prevention ring 5 that abuts and prevents further pull-out movement is fitted in a reduced-diameter biased state. A portion 5a that deforms or breaks when an axial compression force of a certain level or more acts on the inner peripheral edge portion of the pull-out prevention ring 5 on the proximal end side of the insertion tube 3 (for example, the cross-sectional shape is reduced by the compression force). A deformable inwardly opening concave portion (hereinafter referred to as a deformable / destructive portion 5a) is formed in advance. The end surface of the pull-out prevention ring 5 on the proximal end side of the insertion tube 3 except for the outer peripheral side portion formed with a tapered surface 5b for guiding the protection ring 6 to move over the distal end side of the insertion tube 3. It is formed in a planar state orthogonal to or substantially parallel to the axial direction.

In the pipe connection structure having such a configuration, when a pulling force of a certain amount or more is applied to both the pipes 2 and 3 due to landslide, uneven settlement, etc. As shown in (a), (b), and (c), the tip end side of the mouthpiece tube 3 is relatively pressed and moved, and the one end surface 4a of the annular groove 4 in the axial direction is brought into rigid contact with the tip end side 4a. Therefore, the withdrawal movement of the fluid pipe is prevented, and thus the safety of the fluid pipe when the withdrawal force acts is secured. The protection ring 6 is divided into two parts from the state of FIG. 5 (a), and with respect to the pullout prevention ring 5, a part thereof is on the distal end side of the insertion tube 3 and the remaining part is the proximal end of the insertion tube 3. Will be located on the side. Further, when a certain amount of axial compressive force is applied to both pipes 2 and 3 due to an earthquake or the like, the deformed / destructed portion 5a is in the state of FIG. 6 (a) due to the compressive force. 6 to the state shown in FIG. 6B, the apparent compression rigidity of the pipe connection structure is reduced, and even when the compression force is applied, the relative proximity of the two pipes 2 and 3 in the axial direction. It is possible to provide an allowable amount of compressive displacement that allows movement, and thus ensure the safety of the fluid pipe when the compressive force acts.

[0005]

[Problems to be solved by the device]

 There is no room for further improvement in the above-mentioned pipe connection structure, and in order to further improve the safety of the fluid pipe, it is further to provide a pipe connection structure that can avoid the following situations. It is left as room for improvement. That is, in the above-mentioned pipe connection structure, in order to secure the safety of the fluid pipe both when the compression force acts and when the pulling force acts, the inner peripheral edge portion of the pull-out prevention ring 5 on the proximal end side of the insertion pipe 3 In addition, the deformation / destruction portion 5a that effectively acts when the compressive force acts is formed, and the pull-out prevention that effectively acts when the compressive force acts on the outer peripheral surface near the distal end of the insertion tube 3. The annular groove 4 is formed to have a constant groove depth in the axial direction of the tube so that the ring 5 is fitted to the fitting position. Therefore, when the pull-out force is applied, the pull-out prevention ring 5 is moved toward the distal end side of the insertion tube 3 by the pressing force of the protection ring 6 so that the pull-out prevention ring 5 is rigidly brought into contact with the one axial end face 4a of the annular groove 4. In the process, the protective ring 6 falls into the annular groove 4 as shown in FIG. 7 (a), and the deformed / destructed portion 5a is compressed by the pressing force of the protective ring 6 as shown in FIG. 7 (b). It becomes deformed or destroyed in the same way as when a force is applied. Under a certain condition (that is, under the condition that the protection ring 6 is displaced in the radial contraction direction and easily slips into the inner peripheral side of the pullout prevention ring 5), the deformation / destruction portion 5a is actually deformed. Alternatively, the protection ring 6 may entirely sneak into the inner peripheral side of the broken pullout prevention ring 5 (that is, the whole or most of the protection ring 6 sank). When the protective ring 6 as a whole sinks in, the protective ring 6 in the retracted state acts to expand and deform the pull-out prevention ring 5 in the contracted diameter-biased state. As shown in FIG. 7C, the pull-out prevention ring 5 rides up from the inside of the annular groove 4 to the outer peripheral surface of the insertion tube 3, and the pull-out prevention ring 5 causes the pull-out prevention ring 5 to move along the axis of the annular groove 4. As shown in FIG. 7D, it is impossible to make abutting contact with the one end face 4a in the direction, so that it may be impossible to effectively prevent the pull-out movement. The present invention has been made in view of such circumstances, and generally, the safety of the fluid pipe when the pulling force acts and the safety of the fluid pipe when the compressing force acts can be generally ensured, and moreover, the above-mentioned constant It is an object of the present invention to provide a further improved pipe connection structure capable of avoiding the above situation and ensuring the safety of the fluid pipe under the action of the drawing force even under the above condition.

[0006]

[Means for Solving the Problems]

 The feature of the pipe connecting structure according to the present invention is that the pipe is attached to the outer peripheral surface in the vicinity of the distal end of the insertion pipe fitted in the tapered pipe portion of the receiving pipe having the tapered pipe portion having the outward expansion. An annular groove having an appropriate groove width is formed in the axial direction, and based on the pressing force from the proximal end side of the insertion tube, the portion near the proximal end side of the formation position of the annular groove in the insertion tube is formed. A protective ring for protecting the seal ring that seals between the two pipes from the tip end side of the mouthpiece is externally fitted and has a width smaller than the groove width in the annular groove, and When both pipes have moved relative to each other in the drawing direction by a certain amount or more, the C-shaped pulling-out prevention ring which is in rigid contact with one end face in the axial direction of the annular groove and prevents further pulling-out movement is in a reduced-diameter urging state. Align it with the fitting position, and attach it to the inner peripheral edge of the removal prevention ring on the proximal end side of the insertion tube. A pipe connection structure in which a portion that is deformed or destroyed when a compressive force in the axial direction of a certain level or more is applied is formed in advance, and a state in which a compressive force along the axial direction acts on both pipes. However, even if a force is applied in the pulling direction, a fin-shaped guide portion that guides the inner peripheral surface of the protection ring so as to translate the protection ring in the axial direction of the pipe is fitted into the insertion tube. The point is that it is provided on the end face of the pull-out prevention ring on the proximal end side of the insertion tube in a state of being freely movable and extending in the axial direction of the tube.

[0007]

[Action]

 First, the safety of the fluid pipe when a pulling force acts on the both pipes and the safety of the fluid pipe when a compressive force acts on the both pipes are generally considered to be conventional. Secured as well. Furthermore, when a relative withdrawal force of a certain level or more acts on both pipes, the protection ring presses the withdrawal prevention ring toward the tip of the insertion tube based on the withdrawal force, and the pressing force causes The pull-out preventing ring in the diametrically-biased state moves toward the distal end side of the insertion tube so as to be rigidly contacted with one end face in the axial direction of the annular groove, but in the pipe connecting structure of the present invention, Since the fin-shaped guide portion is provided on the end surface of the pull-out prevention ring on the proximal side of the insertion tube, the inner circumference of the pull-out prevention ring is reduced under certain conditions (that is, the protection ring is displaced in the radial contraction direction). Under the condition that the pull-out prevention ring easily slips into the side, the inner peripheral surface of the pull-out prevention ring moves to the distal end side of the insertion tube while being guided by the fin-shaped guide portion. Protection to the circumference Grayed comes to is suppressed that overall slips. As a result, the expansion prevention deformation of the pullout prevention ring, which has occurred conventionally due to the overall diving of the protection ring, is avoided, and as a result, the expansion prevention deformation of the extraction prevention ring to the outer peripheral surface of the inlet pipe is caused. It is also possible to avoid riding on the vehicle, and thus to avoid the situation in which the pull-out movement cannot be effectively prevented.

[0008]

[Effect of device]

 Therefore, according to the present invention, the safety of the fluid pipe under the action of the pulling force and the safety of the fluid pipe under the action of the compressive force can be generally ensured, and the above-mentioned situation can be avoided even under the certain conditions. Then, the conventional problem can be solved.

[0009]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same reference numerals as those in the conventional example indicate the same or corresponding portions.

FIG. 1 shows an embodiment in which a gas pipe is connected in a watertight and airtight state by using the pipe connection structure according to the present invention. In the figure, 2 is a taper of an outward expansion at an end. It is a cast iron socket tube having a tube portion 1.

In the tapered pipe portion 1 of the receiving pipe 2, a cast iron insertion pipe 3 is inserted and arranged concentrically so that the two pipes 2 and 3 are fitted together. An annular groove 4 having an appropriate groove width in the axial direction of the tube is formed on the outer peripheral surface near the front end of the insertion tube 3 so that the groove depth is constant in the axial direction of the tube. .

In the vicinity of the base end side of the formation position of the annular groove 4 in the insertion tube 3, the pressing force from the base end side of the insertion tube 3 (specifically, the tapered tube portion 1 is provided. A seal that seals between the two pipes 2 and 3 based on (the pressing force by the push ring 9 that is moved to the distal end side of the insertion pipe 3 by the bolt 10 that is tightened with the nut while the head is locked to the flange portion 1A). A protective ring 6 (for example, a rubber-impregnated fibrous body) for protecting the ring 7 (for example, a rubber annular gasket or the like) from the distal end side of the insertion tube 3 is externally positioned.

The annular groove 4 has a width smaller than the groove width thereof, and when the both tubes 2 and 3 relatively move in the drawing direction by a certain amount or more, the annular groove 4 has a certain axial direction. A steel C-shaped pull-out prevention ring 5 (specifically, a side-view C-shaped elastic C-ring) that comes into rigid contact with the end face 4a and prevents further pulling movement is in a diametrically urged state. The mating position is.

A portion 5a that deforms when an axial compression force of a certain level or more acts on the inner peripheral edge of the pull-out prevention ring 5 on the proximal end side of the insertion tube 3 (specifically, the compression force Therefore, an inwardly-opening recess whose cross-sectional shape can be reduced and deformed (hereinafter, simply referred to as recess 5a) is formed in advance. A taper surface 5b is formed on the outer peripheral portion of the pull-out prevention ring 5 on the proximal end side of the insertion tube 3 so as to guide the protection ring 6 over the distal end side of the insertion tube 3 for movement.

On the end face of the pull-out prevention ring 5 on the proximal end side of the insertion tube 3, a fin-shaped guide portion 5d is in a state in which the insertion tube 3 can be fitted therein and extends in the axial direction of the tube. It is provided in. The fin-shaped guide portion 5d guides the protection ring 6 to the tube 2 regardless of whether a compressive force along the axial direction acts on the tubes 2 and 3 or a force in the pulling direction. It is designed to guide the inner peripheral surface of the protection ring 6 so as to be translated in the axial direction. The fin-shaped guide portion 5d may exist over the entire circumference in the pipe circumferential direction, or may partially exist in the pipe circumferential direction.

Next, the procedure for connecting gas pipes using the pipe connection structure having such a configuration will be described. First, the push ring 9, the seal ring 7, and the protective ring 6 are sequentially fitted onto the insertion tube 3 from the tip side thereof, and finally, the pull-out prevention ring 5 is fitted into the annular groove 4. . Since the pull-out prevention ring 5 is configured as a so-called elastic C ring, the pull-out prevention ring 5 is externally fitted on the insertion tube 3 while being elastically expanded and deformed by applying a diameter expansion deformation force. Then, when the diametrical expansion force is released and moved to the position of the annular groove 4, the pull-out prevention ring 5 is released from the diametrical expansion deformation and elastically returns to its original shape, and is fitted into the annular groove 4. Become so. Next, the insertion pipe 3 to which the above-mentioned members are fitted is inserted and arranged concentrically into the tapered pipe portion 1 of the receiving pipe 2, and the flange portion 1A of the tapered pipe portion 1 and the push ring are inserted. The flange portion 9a of 9 is tightened so as to approach each other in the axial direction via a plurality of bolts 10 in the circumferential direction, so that the inner peripheral surface of the tapered pipe portion 1 and the outer peripheral surface of the insertion pipe 3 are separated from each other. The seal ring 7 located between them is pressed via the push ring 9 toward the axial direction of the pipe axis and toward the pull-out prevention ring 5, so that the seal ring 7 becomes the inner peripheral surface of the taper pipe portion 1. The two pipes 2 and 3 are connected to each other in a desired water-tight and air-tight state where they are elastically and deformed to the outer peripheral surface of the insertion pipe 3.

In the pipe connecting structure having such a structure, when a pulling force of a certain amount or more is applied to both the pipes 2 and 3 due to landslide, uneven settlement, etc. As shown in (a), (b), and (c), the tip end side of the mouthpiece tube 3 is relatively pressed and moved, and the one end surface 4a of the annular groove 4 in the axial direction is brought into rigid contact with the tip end side 4a. Therefore, the withdrawal movement of the fluid pipe is prevented, and thus the safety of the fluid pipe when the withdrawal force acts is secured. The protection ring 6 is divided into two parts from the state of FIG. 2 (a), and with respect to the pull-out prevention ring 5, a part thereof is on the distal end side of the insertion tube 3 and the remaining part is the proximal end of the insertion tube 3. Will be located on the side.

When a certain amount of axial compressive force is applied to both the pipes 2 and 3 due to an earthquake or the like, the recess 5a is deformed by the compressive force (mechanism of this deformation). Since the same as in the conventional case, see FIGS. 6 (a) and 6 (b)), the apparent compression rigidity of the pipe connection structure is reduced, and even when the compression force is applied, the two pipes 2, It is possible to provide a permissible compressive displacement amount that allows the relative movement of the shaft 3 in the axial direction, thereby ensuring the safety of the fluid pipe when the compressive force acts.

Further, when a relative drawing force of a certain level or more is applied to both the pipes 2 and 3, the protection ring 6 presses the pull-out blocking ring 5 toward the tip end side of the insertion pipe 3 based on the pulling force. The pressing force causes the pull-out prevention ring 5 in the reduced-diameter biased state to move toward the distal end side of the insertion tube 3 so as to be rigidly abutted against one end face in the axial direction of the annular groove 4. However, in the pipe connection structure of the present invention, since the fin-shaped guide portion 5b is provided on the end face of the pull-out prevention ring 5 on the base end side of the insertion pipe 3 as described above, under certain conditions. Even under the condition that the protective ring 6 is displaced in the radial contraction direction and easily slips into the inner peripheral side of the pullout prevention ring 5, the inner peripheral surface of the protective ring 6 is as shown in FIG. Is guided by the fin-shaped guide portion 5d as shown in FIG. Therefore, it is possible to prevent the protection ring 6 from being entirely submerged in the inner peripheral side of the pullout prevention ring 5 as a result. As a result, the diameter-expanding deformation of the withdrawal blocking ring 5, which has occurred in the prior art, can be avoided based on the overall diving of the protection ring 6. Therefore, the expansion preventing deformation of the pull-out preventing ring 5 (see FIG. 7B), which has conventionally occurred due to the overall diving of the protection ring 6, is avoided, so that the pull-out preventing ring 5 based on the expand expanding deformation. Riding on the outer peripheral surface of the insertion tube 3 (see FIG. 7C) can be avoided, and thus the situation in which the above-mentioned pull-out movement cannot be effectively prevented can be avoided.

Next, another embodiment will be described. In the above-described embodiment, the inner peripheral edge portion of the pull-out prevention ring 5 on the proximal end side of the insertion tube 3 is formed with the concave portion 5a that is deformed when a certain amount of axial compressive force is applied. Instead of the concave portion 5a, a material having low rigidity such as plastic is filled in the inner peripheral edge portion of the pull-out prevention ring 5 on the proximal end side of the insertion tube 3, and the inner peripheral edge portion is subjected to a certain axial compression force. The pipe connection structure according to the present invention can be applied even if the portion that is deformed or destroyed when being formed is constructed. In this case, the deforming or breaking portion may be formed at the edge of the pull-out blocking ring 5 on the proximal end side of the insertion tube 3 (see FIG. 3).

Further, in the above-mentioned embodiment, the gas pipe is connected in a watertight and airtight state by using the pipe connection structure according to the present invention. It is also conceivable to connect the water pipes (for example, water pipes) in a watertight and airtight state.

In the claims of the utility model registration, reference numerals are given for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a pipe connecting structure according to the present invention.

FIG. 2 is an explanatory view of the pipe connection structure when a pulling force is applied.

FIG. 3 is a sectional view showing another embodiment of the pipe connection structure according to the present invention.

FIG. 4 is a sectional view showing a conventional pipe connection structure.

FIG. 5 is an explanatory view of a conventional pipe connection structure when a compressive force is applied (normal)

FIG. 6 is an explanatory view of a conventional pipe connection structure when a pulling force is applied (when normal)

FIG. 7 is an explanatory view of a conventional pipe connection structure when a pulling force is applied (at the time of abnormality)

[Explanation of symbols]

 1 Taper pipe part 2 Receiving pipe 3 Inserting pipe 4 Annular groove 4a One end face in the axial direction 5 Extraction prevention ring 5a Deformation or destruction part 5d Fin-shaped guide part 6 Protective ring 7 Seal ring

Claims (1)

[Scope of utility model registration request] 1. A tapered pipe portion (1) having an outer flared end.
An annular groove having an appropriate groove width in the axial direction of the tube on the outer peripheral surface near the tip of the insertion tube (3) fitted in the tapered tube portion (1) of the receiving tube (2) having (4) is formed, and in the portion near the base end side of the formation position of the annular groove (4) in the insertion pipe (3), both of the above are formed based on the pressing force from the base end side of the insertion pipe (3). A protection ring (6) for protecting the seal ring (7) for sealing between the pipes (2) and (3) from the distal end side of the insertion pipe (3) is externally fitted to the inside of the annular groove (4). Has a width smaller than the groove width, and when the two pipes (2), (3) relatively move in the drawing direction by a certain amount or more, one end face (4a) in the axial direction of the annular groove (4). The C-shaped pull-out prevention ring (5), which comes into rigid contact with and is prevented from further pulling-out movement, is fitted to the reduced-diameter urging state, and the pull-out prevention ring A pipe connection structure in which a portion (5a) that deforms or breaks when an axial compressive force of a certain level or more acts is formed in advance on the inner peripheral edge portion on the proximal end side of the insertion pipe (3) in the ring (5). The protective ring (6) is attached to the tube shaft (2) regardless of whether a compressive force along the axial direction acts on the both tubes (2), (3) or a force in the drawing direction. A fin-shaped guide portion (5d) that guides the inner peripheral surface of the protection ring (6) so as to be translated in the axial direction is inserted into the insertion tube (3) and extends in the axial direction of the tube axis. In this state, the pipe connection structure is provided on the end face of the pull-out prevention ring (5) on the proximal end side of the insertion pipe (3).