JP2002168385A - Coupling for flexible pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent disengaging of a flexible pipe. SOLUTION: A supporting member 6 is adjacently arranged in a front side of an engaging member 7 in the inserting direction of the flexible pipe G1. Accordingly, when the engaging member 7 is moved to the front side in the inserting direction of the flexible pipe G1, the engaging member 7 abuts against an end face 36 of the supporting member 6, thereby preventing the engaging member 7 from moving in the same direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible pipe joint used for connecting a bellows-shaped flexible pipe.

[0002]

2. Description of the Related Art A conventional joint of this type has a joint body in which a connection hole into which a flexible pipe is inserted is formed, and a cylindrical supporting member is movable in the connection hole of the joint body. In addition, an engaging member capable of expanding and contracting the diameter is supported on the outer periphery of the supporting member in an expanded state. Then, when the flexible tube is inserted into the connection hole from one end opening thereof, the support member is moved in the same direction by the flexible tube. As a result, the engaging member falls off from the supporting member, the diameter of the engaging member is reduced, and the engaging member is fitted to the valley of the flexible pipe. The engagement member fitted to the valley of the flexible pipe abuts on a locking surface provided in the connection hole, thereby preventing the connection hole from moving toward the one end opening side. Thereby, the flexible tube is prevented from coming off and connected to the joint body (see Japanese Patent Application Laid-Open No. 5-306790).

In the joint for a flexible pipe having the above structure, when a force is applied to the flexible pipe to pull it out of the connection hole, the outer circumference of the flexible pipe is wavy. The force to act acts. For this reason, if the locking surface is formed in a plane perpendicular to the axis of the connection hole, the diameter of the engaging member increases, and the flexible pipe may fall out of the connection hole even with a relatively small force. is there.

Therefore, in the conventional flexible pipe joint, the locking surface is formed as a tapered surface having a small diameter in a direction in which the flexible pipe is pulled out (a direction from the other end to the one end of the connection hole). When the engaging surface has such a tapered surface, when the engaging member abuts against the engaging surface, the engaging surface not only prevents the engaging member from moving in the pull-out direction, but also reduces the diameter of the engaging member. Try to let it. Therefore, the connection strength of the flexible pipe can be improved.

[0005]

However, the conventional joint cannot sufficiently prevent the flexible pipe from coming off when a large tensile force is applied to the flexible pipe such that the flexible pipe extends in the longitudinal direction. could not. Therefore, there has been a demand for the development of a joint capable of preventing the flexible pipe from coming off more strongly.

[0006]

SUMMARY OF THE INVENTION The present invention meets the above-mentioned demands, and comprises a joint body having a connecting hole into which a bellows-shaped flexible pipe is inserted from one end opening toward the other end. An engagement member which is provided inside the connection hole and which can be expanded and contracted to fit into a valley portion of the flexible tube inserted into the connection hole; And a locking surface for preventing movement from the other end to the one end of the connection hole via the engaging member. The diameter of the locking surface decreases from the other end to the one end of the connection hole. In the flexible pipe joint formed on the tapered surface, the movement for preventing the engagement member fitted to the valley of the flexible pipe from moving from one end to the other end of the connection hole inside the connection hole. It is specially noted that It is set to. In this case, a cylindrical screw member through which the flexible tube can be inserted is screwed into one end opening of the connection hole, and the locking surface is formed on the inner peripheral surface of the distal end portion of the screw member in the insertion direction of the flexible tube. It is desirable to do. Inside the connection hole, a cylindrical support member for supporting the engagement member in an expanded state is provided so as to be movable in the axial direction of the connection hole, and the support member is connected to one end of the connection hole by the flexible pipe. By preventing the engagement member from moving in the same direction when it is moved from the side to the other end, the engagement member is dropped from the support member and fitted to the valley of the flexible tube. It is preferable that a stopper is provided, and an end of the support member at one end of the connection hole is the movement inhibiting portion. Inside the connection hole, a seal member having a seal portion against which the distal end of the flexible tube abuts on the inner peripheral surface is slidably provided. It is desirable to provide a contact surface that abuts on the end surface of the seal member at the other end of the connection hole when moved to the end side, and connects the support member to the seal member.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In this embodiment, the present invention is applied to a joint 1 for a flexible pipe to which a flexible gas pipe F is connected. FIG. 1 shows the joint 1 before the flexible gas pipe F is connected, and FIG.
3 shows a state in which the flexible gas pipe F is being connected, and FIG.
Indicates a joint 1 in which the connection of the flexible gas pipe G is completed. The flexible gas pipe G is composed of a metal flexible bellows-like flexible pipe (hereinafter abbreviated as a flexible pipe) G1 and a resin coating pipe G2 that covers the outer periphery of the flexible pipe F1. .

As shown in FIGS. 1 to 3, the flexible pipe joint 1 includes a joint main body 2. This joint body 2
Is formed with a connection hole 21 that penetrates a central portion from one end (left end in FIGS. 1 to 3; hereinafter, one end is referred to as a left end) to the other end (hereinafter, referred to as a right end). On the inner peripheral surface of the connection hole 21, a female screw portion 22, an annular receiving recess 23 having a larger diameter than the female screw portion 22, a sliding hole portion 24 having a diameter slightly smaller than the female screw portion 22 are provided from the left end to the right end.
An outlet hole 25 having a diameter smaller than that of the sliding hole 24 is sequentially formed. An annular contact surface 26 is formed between the sliding hole 24 and the outlet hole 25. The contact surface 26 is formed as an annular flat surface facing leftward and orthogonal to the axis of the connection hole 21. A tapered external thread 27 is formed on the outer peripheral surface of the right end of the joint body 2. The joint main body 2 is connected to a gas appliance by screwing the tapered male thread portion 27 into an inflow port of a gas appliance (not shown). The joint body 2 may be formed integrally with a gas appliance as a part thereof.

The right end of the cylindrical screw member 3 is screwed into the female screw portion 22. A large-diameter hole 31 through which the cladding tube G2 can be inserted is formed at the left portion of the inner periphery of the screw member 3, and only the flexible tube G1 can be inserted at the right portion, and the coating tube G2 cannot be inserted. A certain small-diameter hole 32 is formed. Therefore, when inserting the flexible gas pipe G into the connection hole 21 through the screw member 3, the covering pipe G2 is cut off in advance by a predetermined length from the tip. Large diameter hole 31
Is provided with a seal member 33 for preventing rainwater from entering the joint body 2 from between the outer peripheral surface of the cladding tube G2 and the inner peripheral surface of the large-diameter hole portion 31. A seal member 34 is provided on the inner peripheral surface of the small diameter hole 32. The seal member 34 expands in the event of a fire and comes into pressure contact with the outer peripheral surface of the flexible tube G1 to prevent gas from leaking from between the outer peripheral surface of the flexible tube G1 and the inner peripheral surface of the small-diameter hole 32.

The outer peripheral surface of the left end of the screw member 3 has a large diameter portion 3
5 are formed. A positioning member 4 is provided between the outer peripheral surface of the large diameter portion 35 and the outer peripheral surface of the left end portion of the joint body 2. The positioning member 4 is formed of a relatively hard resin into a cylindrical shape, and the left end portion thereof has a large diameter portion 3.
5 is fitted and fixed to the outer peripheral surface. An annular projection 41 is formed on the right end of the positioning member 4. In an initial state before the flexible gas pipe G is connected to the joint 1, the annular protrusion 41 is fitted into the first locking concave portion 28 formed on the outer peripheral surface of the joint main body 2 as shown in FIG. I have. As a result, the large diameter portion 35 is maintained at the initial position separated from the left end surface of the joint body 2 by a predetermined distance. However, when the annular projection 41 is pushed rightward by a force equal to or more than a predetermined amount, the annular projection 41 can be expanded in diameter and come out of the first locking recess 28. Therefore, when the screw member 3 is screwed in with a force equal to or larger than a predetermined magnitude, the annular projection 41 comes out of the first locking recess 28. When the large-diameter portion 35 reaches just before the large-diameter portion 35 abuts against the left end surface of the joint body 2, the annular projection 41 is moved to the second position.
It is fitted into the locking recess 29 immovably to the left. Thereby, the screw member 3 is prevented from coming off. When the annular projection 41 fits into the second locking recess 29, the right end of the positioning member 4 abuts on the outer peripheral surface of the joint body 2 due to its own elasticity, and generates an impact sound. The screw member 3 is screwed until the large diameter portion 35 abuts on the left end surface of the joint body 2.

In the sliding hole 24, a seal member 5 made of an elastic material such as rubber is provided so as to be slidable and airtight. The seal member 5 has a cylindrical shape, and a small diameter portion 51 having substantially the same diameter as the inner diameter of the outlet hole 25 is formed on the inner peripheral surface at the right end. The inner diameter of the small diameter portion 51 is slightly smaller than the minimum diameter of the flexible tube F1.
Therefore, the flexible pipe G1 does not penetrate the seal member 5. A seal portion 52 is formed at a portion adjacent to the left side of the small diameter portion 51 on the inner peripheral surface of the seal member 5. When the distal end of the flexible tube G1 abuts on the seal portion 52, the distal end of the flexible tube G1 is
Is hermetically sealed with the inner peripheral surface of the airbag. in this case,
The seal portion 52 is formed in the same shape as the portion from the valley portion at the most distal end of the flexible tube G1 (the flexible tube F1 is usually cut at the smallest diameter portion of the valley portion) to the ridge portion, so that the seal is formed. The performance is improved.

When the distal end of the flexible pipe G1 abuts against the seal portion 52, the seal member 5 is pushed in the same direction with the insertion of the flexible gas pipe G, and moves rightward until its right end face abuts against the contact surface 26. Moving. When the seal member 5 abuts against the contact surface 26, the flexible gas pipe G cannot be inserted any more. In this state, the space between the seal member 5 and the contact surface 26 is hermetically sealed. In particular,
In this embodiment, the sealing property is improved by forming the annular projection 53 on the right end face of the sealing member 5.

The sealing member 5 includes a cylindrical supporting member 6.
The right end of is buried. Thereby, the support member 6
Are connected so as to move integrally with the seal member 5. The support member 6 is not connected to the seal member 5,
It may be provided separately from the seal member 5. However,
In the case where the support member 6 is provided alone, the support member 6 is configured to be moved rightward by the flexible tube G1 when the flexible tube G1 is further inserted into the connection hole 21 beyond a predetermined position. There is a need.

At the right end of the support member 6 corresponding to the small diameter portion 51 of the seal member 5, an annular projecting portion 61 projecting radially inward is formed. The annular protrusion 61 is disposed between the right end face of the seal member 5 and the seal portion 52, and prevents the seal portion 52 from being greatly deformed when the flexible tube G1 strikes the seal portion 52. I do.
Thereby, while increasing the contact pressure between the flexible pipe G1 and the seal portion 52, the right end surface of the seal member 5 and the contact surface 26
The contact pressure with is also increased.

The left end of the support member 6 projecting leftward from the seal member 5 faces the housing recess 23, and the engaging member 7 is fitted around the outer periphery of the left end. The engagement member 7 is formed by connecting both ends of a coil body into an annular shape, for example. Accordingly, the diameter of the engaging member 7 can be increased and reduced, and the engaging member 7 is fitted to the support member 6 in the expanded state. Engaging member 7
Is made of a wire having a large wire diameter for its diameter. Therefore, the coil body has a large strength in the radial direction, and even if a large force acts in the radial direction of the coil body, the coil body is hardly crushed and deformed into an elliptical diameter.

The engaging member 7 fitted to the support member 6 initially moves rightward together with the support member 6 when the support member 6 is moved rightward together with the seal member 5 by the flexible tube F1. However, when the storage recess 23 moves slightly to the right,
And it cannot move further to the right. Therefore, as shown in FIG. 2, when the support member 6 further moves rightward until the annular projection 53 of the seal member 5 abuts against the contact surface 26,
The engagement member 7 moves to the left relative to the support member 6, and gets out of the support member 6 by riding over the low-height annular ridge 62 formed on the outer peripheral surface of the left end portion of the support member 6. . As a result, the diameter of the engagement member 7 is reduced by its own elasticity, and the engagement member 7 fits into the valley of the flexible pipe G1. The outer diameter of the engaging member 7 is set such that when fitted into the valley of the flexible tube G1, almost half of the outside protrudes outward from the peak of the flexible tube G1. The diameter of the engagement member 7 is slightly increased even when the engagement member 7 is fitted in the valley.

As soon as the engagement member 7 comes off the support member 6, it is fitted into the valley of the flexible tube G1. Therefore, the engagement member 7 and the support member 6 fitted into the valley are connected to the connection hole 21.
When the engaging member 7 moves slightly rightward, the left end surface of the support member 6 (movement preventing portion)
Hits 63. This prevents further movement of the engagement member 7 to the right.

An engaging surface 36 is formed at the right end of the inner peripheral surface of the screw member 3. The locking surface 36 is formed as a tapered surface having a smaller diameter as going from the right side to the left side, and its inclination angle is set to about 30 ° to 45 °. That is, the taper angle of the locking surface 36 is 6
The angle is set to about 0 ° to 90 °. The locking surface 36 is arranged such that when the screw member 3 is screwed into the connection hole 21 and the large diameter portion 35 reaches a position slightly before the left end surface of the joint body 2, the locking surface 36 abuts on the engagement member 7. . Therefore,
When the screw member 3 is further screwed in until the large diameter portion 34 abuts on the joint body 2, the screw member 3 pushes the flexible pipe G <b> 1 rightward through the engaging member 7, and the distal end of the flexible pipe G <b> 1 The right end surface of the seal member 5 is strongly pressed against the contact surface 26 while strongly pressing the seal portion 52. This allows the contact surfaces to be more airtightly sealed. Moreover, when the locking surface 36 abuts against the engaging member 7, the engaging member 7 is prevented from moving leftward, and thus the flexible tube G1 is prevented from moving leftward. Thereby, the flexible gas pipe G is connected to the joint 1 in a state where it is prevented from falling off.

A flexible gas pipe G is connected to the joint 1 having the above structure.
Is connected, the cladding tube G2 is previously cut off from the tip by a predetermined length. Then, the flexible gas pipe G is inserted into the connection hole 21 via the screw member 3. When the distal end of the flexible pipe G1 abuts on the seal portion 52, the seal member 5 and the support member 6 move rightward with the insertion of the flexible gas pipe G. When the flexible gas pipe G is inserted to a predetermined position, that is, when the annular projection 5 of the seal member 5 is
When the insertion member 3 is inserted until it abuts against the contact surface 26, the engagement member 7 falls off the support member 6 and fits into the valley of the flexible pipe G1. Thereafter, the screw member 3 is screwed in the insertion direction of the flexible gas pipe G. When the screw member 3 is screwed until the annular projection 41 of the positioning member 4 fits into the second locking recess 29, the locking surface 36 abuts on the engaging member 7. As a result, the flexible pipe G1 (flexible gas pipe G) is connected to the joint 1 in a state where the flexible pipe G1 does not come off. However, the large diameter part 3 is actually
The screw member 3 is further screwed until 5 comes into contact with the left end surface of the joint body 2. This prevents the screw member 3 from easily rotating in a loosening direction, and strongly presses the seal member 5 against the contact surface 26.

FIG. 4 shows a flexible pipe G1 connected to the joint 1.
Pulling force F to pull out from the connection hole 21 to the left
Shows the state at the time of acting, and the pulling force F
Shows a case where the size does not reach a size enough to stretch the flexible tube G1. Pull force F on flexible tube G1
Is applied, the pressing force F1 acts on the engaging member 7.
In this case, the center of the engaging member 7 is C, and the contact points of the engaging member 7 with the flexible pipe G1 and the locking surface 36 are P and Q, respectively.
Then, the line connecting the contact points P and Q is located on the upper right side of the center C. Therefore, the pressing force F1 acts obliquely leftward toward the center of the connection hole 21. Therefore, in this case, the engagement member 7 reliably prevents the flexible tube G1 from being pulled out.

FIG. 5 shows a state where the pulling force F acting on the flexible tube G1 is large and the flexible tube G1 is stretched by the pulling force F. When the flexible tube G1 is expanded, the line connecting the contact points P and Q is located on the lower left side of the center C of the engaging member 7. Therefore, the pressing force F <b> 1 acting on the engagement member 7 is directed obliquely rightward toward the outside of the connection hole 21. Therefore, assuming that the support member 6 is not provided, the engagement member 7 is moved rightward while expanding its diameter along the tapered locking surface 36 as shown by an imaginary line in FIG. As a result, the peaks of the flexible pipe G1 can easily pass through the engagement member 7, and the flexible pipe G1 can be easily detached from the joint 1.

However, in the joint 1 of the present invention,
Since the left end surface 63 of the support member 6 is located close to and on the right side of the engagement member 7, when the engagement member 7 attempts to move rightward, it abuts against the left end surface 63 of the support member 6 and becomes more Can not move towards Therefore, the diameter of the engaging member 7 cannot be increased. Therefore, the engagement member 7
5 moves to the right and expands in diameter, making it more difficult for the peak portion of the flexible pipe G1 to pass through the engaging member 7. As a result, the tensile force F when the flexible pipe G1 is pulled out from the joint 1 increases.

In order to confirm such an effect, the magnitude of the pulling force F when the flexible pipe G1 is pulled out of the joint 1 depends on whether the movement of the engaging member 7 is blocked by the support member 6 or not. As a result, the tensile force was able to be increased by about 20% in the present invention in which the resistance was measured. In other words, the joint 1 of the present invention
According to the above, the pull-out preventing ability for the flexible tube G1 is 2
It could be improved by about 0%.

The present invention is not limited to the above embodiment, but can be changed as appropriate. For example, in the above-described embodiment, the screw member 3 is screwed into the one end opening of the connection hole 21 and the locking surface 36 is formed on the screw member 3.
It is not necessary to provide the screw member 3 like the one described in Japanese Patent Publication No. 90. In that case, the locking surface 36 may be formed on the inner peripheral surface of the connection hole 21 or another member provided inside the connection hole 21.

[0025]

As described above, according to the present invention, the pulling force when the flexible pipe is pulled out from the joint can be increased, and the flexible pipe can be strongly stopped by that much. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention in a state before a flexible gas pipe F is connected.

FIG. 2 is a cross-sectional view of the same embodiment in a state where a flexible gas pipe F is being connected.

FIG. 3 is a sectional view showing the same embodiment in a state where connection of a flexible gas pipe G is completed.

FIG. 4 is an enlarged cross-sectional view of a main part showing a force acting on the engaging member when a relatively small force trying to pull out from the connection hole acts on the flexible tube of the embodiment.

FIG. 5 is an enlarged sectional view of a main part showing a force acting on the engaging member when a force large enough to extend the flexible tube acts on the flexible tube of the embodiment.

FIG. 6 shows a state in which the support member prevents the engaging member from moving to the larger diameter side of the locking surface when a force large enough to stretch the flexible tube of the embodiment is applied. It is an expanded sectional view of the important section showing.

[Explanation of symbols]

 G1 Flexible pipe 1 Joint 2 Joint body 3 Screw member 5 Seal member 6 Support member 7 Engagement member 21 Connection hole 23a Right side surface (locking portion) of accommodation recess 26 Contact surface 36 Locking surface 63 Left end surface of support member ( Movement prevention part)

Claims (4)

[Claims] 1. A joint body having a connection hole into which a bellows-shaped flexible pipe is inserted from one end opening toward the other end, and expansion and contraction fitting into a valley of the flexible pipe inserted into the connection hole. The engagement member is provided inside the connection hole and is capable of moving the flexible tube from the other end to the one end of the connection hole by contacting the engagement member. A flexible pipe joint formed with a tapered surface having a smaller diameter as it goes from the other end to the one end of the connection hole. A flexible pipe joint, further comprising a movement preventing portion for preventing an engaging member fitted to a valley of the flexible pipe from moving from one end to the other end of the connection hole. 2. A cylindrical screw member through which the flexible tube can be inserted is screwed into one end opening of the connection hole, and the locking surface is provided on an inner peripheral surface of a distal end portion of the screw member in the insertion direction of the flexible tube. 2. The method according to claim 1, wherein
The joint for flexible pipes according to the above. 3. A cylindrical support member for supporting the engaging member in an expanded state is provided inside the connection hole so as to be movable in the axial direction of the connection hole, and the support member is provided by the flexible tube. By preventing the engagement member from moving in the same direction when being moved from one end to the other end of the connection hole, the engagement member is dropped from the support member and the valley portion of the flexible tube is removed. 3. The flexible pipe joint according to claim 1, wherein an engaging portion is provided to be fitted to the connecting hole, and an end of the support member at one end of the connection hole is the movement preventing portion. 4. A seal member having a seal portion on the inner peripheral surface of which the tip of the flexible tube abuts is slidably provided inside the connection hole, and the seal member is connected to the connection hole by the flexible tube. A contact surface abutting against an end surface of the seal member at the other end of the connection hole when the support member is moved from one end to the other end of the connection hole, and the support member is connected to the seal member. The flexible pipe joint according to claim 3.