JP2008240771A - Sealing method and sealing structure of joint for flexible pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform connection in the sealed form by one-touch operation in which a flexible pipe is only inserted, to make hardly influenced with regard to deformation of the flexible pipe and bending or the like after construction, and to attain enhancement of sealing performance. <P>SOLUTION: A cylindrical rubber seal 6 is stored at the inside of a receiving port part 3 of a coupling body 5 such that an outer periphery of a second projection part 6c outwardly and projectedly formed is abutted on a taper surface 10. A distal end of the flexible pipe 2 is inserted to the inside of the rubber seal 6 following that the distal end is inserted to the receiving port part 3, and it is abutted on the first projection part 6b and pushes-in the rubber seal 6 in an inner depth direction of the receiving port part. Following the push-in, the second projection part 6c is slide-contacted with the taper surface 10, is inwardly radially contracted/deformed and is closely adhered to a slant surface 8a of a bottom part 8 of the flexible pipe 2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sealing method and a sealing structure for a joint for a flexible pipe that can be sealed by a one-touch operation of inserting a flexible pipe for guiding a fluid such as gas or liquid.

  As a plug-in type flexible pipe joint of this type, for example, as shown in FIG. 7, a joint body 31 in which a large-diameter hole 31 a, a medium-diameter hole 31 b, and a small-diameter hole 31 c are formed in order from the inlet side. The intermediate diameter hole 31b is slidably mounted, the inlet side extends to the large diameter hole 31a of the joint body 31, and the sleeve 33 that engages with the distal end portion of the flexible pipe 32 is formed in an annular shape and is elastically expanded and contracted. In a free state, the ring spring 34 is fitted into the outer periphery of the valley 32b of the flexible tube 32, and is expanded and attached to the outer surface of the inlet side of the sleeve 33, and is screwed to the inlet side of the joint body 31 via the O-ring 35. The packing 36 is attached to the inner peripheral surface, and the inner peripheral surface at the inner back end is larger than the outer diameter of the ring spring 34 when the ring spring 34 is fitted into the outer periphery of the valley portion 32b of the flexible pipe 32. There is provided with the pressing ring 37 which is smaller in diameter, (see Patent Document 1.).

JP-A-6-185680

  However, the flexible pipe joint sealing structure in which the packing 36 is compressed by the crests 32a of the flexible pipe 32 to prevent fluid leakage is poor in followability to deformation of the flexible pipe 32 such as dents and flattening, so that fluid leaks. In addition, there is a problem that it is easily affected by bending after the construction of the flexible pipe 32 and causes fluid leakage.

  The present invention has been made to solve such problems, and the object of the present invention is that it can be connected in a seal-like manner by a so-called one-touch operation by simply inserting the flexible tube, An object of the present invention is to provide a sealing method and a sealing structure for a joint for flexible pipes which can be hardly affected by bending after construction and the like and can improve sealing performance.

  In order to achieve the above object, the present invention will be described with reference to the reference numerals attached to FIGS. 1 to 4 to facilitate understanding of the contents of the invention. Of the flexible pipe 2 in which crests 7 and troughs 8 extending in the circumferential direction are arranged alternately in the pipe axis direction on the receiving part 3 of the joint body 5 having the receiving part 3 at the outer periphery. In the sealing method of the joint for flexible pipes, in which the tip part is inserted and the gap between the inner periphery of the receiving part 3 and the outer periphery in the vicinity of the tip part of the flexible pipe 2 is sealed with the rubber seal 6, the rubber seal 6 includes the peripheral wall part 6a, In a cylindrical shape having an annular first protrusion 6b projecting inwardly on the inner periphery of the front end of the peripheral wall 6a and an annular second protrusion 6c projecting outward on the outer periphery of the rear end of the peripheral wall 6a. The tapered surface 10 is formed on the inner periphery of the receiving part 3 toward the inner part of the receiving part. A small-diameter hole 11 is formed in a continuous shape at the small-diameter side end of the tapered surface 10, and the rubber seal 6 has the small-diameter so that the outer periphery of the second protrusion 6 c contacts the tapered surface 10. It is accommodated in the hole 11, and as the distal end portion of the flexible tube 2 is inserted into the receiving portion 3, the distal end portion is inserted into the rubber seal 6 and comes into contact with the first projecting portion 6 b to receive the rubber seal 6. At least the inclined surface of the valley portion 8 of the flexible tube 2 is deformed inwardly by being pushed inwardly into the mouth portion 3 and the second protrusion 6c is slidably contacted with the tapered side of the tapered surface 10 along with the pushing. It is characterized by being in close contact with 8a.

According to such a configuration, the sealed state by the rubber seal 6 between the outer peripheral surface near the tip of the flexible tube 2 and the inner peripheral surface of the small diameter hole 11 of the joint body 5 is the second protrusion 6 c of the rubber seal 6. Is obtained by being in close contact with at least the inclined surface 8a of the valley portion 8 of the flexible tube 2, so that the distal end portion inserted into the joint body 5 of the flexible tube 2 or the deformation in the vicinity of the distal end portion and the bending after the construction are performed. Etc., and the sealing performance can be improved.
Further, as the flexible tube 2 is inserted into the receiving portion 3 of the joint body 5, the distal end portion of the flexible tube 2 is inserted into the rubber seal 6 and comes into contact with the first protrusion 6 b so that the rubber seal 6 is inserted into the receiving portion 3. The second protrusion 6c is slidably in contact with the tapered side of the tapered surface 10 along with the pressing, so that the diameter of the second protrusion 6c is reduced inward so as to be in close contact with the trough 8 of the flexible tube 2. Therefore, it can seal easily by one-touch operation only to insert the flexible tube 2.
Furthermore, since the rubber seal 6 protrudes outward from the second protrusion 2c at the beginning, that is, before the flexible pipe is inserted, the distal end is supported by the second protrusion 6c when the distal end of the flexible pipe 2 is inserted. Therefore, the flexible tube 2 can be smoothly inserted into the rubber seal 6 without causing an obstacle to insertion, and the ease of insertion of the flexible tube 2 can be ensured.

In order to achieve the above object, the present invention will be described with reference to the reference numerals attached to FIG. 4 in order to facilitate understanding of the contents of the invention as described in claim 2. A flexible pipe 2 in which crests 7 and troughs 8 extending over the entire circumference in the direction are alternately arranged in the pipe axis direction, and a joint body 5 having a receiving part 3 for receiving the tip of the flexible pipe 2 at one end. In the seal structure of the joint for flexible pipes, which includes a rubber seal 6 for sealing between the inner periphery of the receiving port 3 of the joint body 5 and the outer periphery in the vicinity of the distal end of the flexible tube 2, A tapered surface 10 is formed in the inner periphery so as to be constricted toward the inner side of the receiving portion, and a small diameter hole 11 is formed in a communication shape at a small diameter side end of the tapered surface 10, and the peripheral wall portion 6 a and the peripheral wall portion An annular first projecting inwardly on the inner periphery of the tip of 6a A flexible tube in which the rubber seal 6 formed into a cylindrical shape having a protrusion 6b and an annular second protrusion 6c projecting outward on the outer periphery of the rear end of the peripheral wall 6a is inserted into the receiving portion 3 2 is fitted into the vicinity of the distal end portion of the flexible tube 2 and is pressed into the small-diameter hole 11 by receiving the pressing action by the distal end portion of the flexible tube 2 into the small-diameter hole 11 and is slidably contacted with the tapered surface 10 along with the pressing. The second projecting portion 6 c that has been deformed inwardly in diameter is in close contact with at least the inclined surface 8 a of the valley portion 8 of the flexible tube 2.
According to such a configuration, the sealed state by the rubber seal 6 between the outer peripheral surface near the tip of the flexible tube 2 and the inner peripheral surface of the small diameter hole 11 of the joint body 5 is the second protrusion 6 c of the rubber seal 6. Is obtained by adhering to at least the inclined surface 8a of the valley portion 8 of the flexible tube 2, so that the distal end portion inserted into the joint body 5 of the flexible tube 2 and the deformation of the vicinity of the distal end portion and the influence on the bending after the construction are affected. It becomes hard to receive and can improve sealing performance.
In addition, the rubber seal 6 is pressed into the small-diameter hole 11 by receiving the pressing action by the tip of the flexible tube 2 inserted in the receiving portion 3 into the small-diameter hole 11, and the taper surface 10 is pressed with the pressing. Since the second protrusion 6c slidably contacted and contracted inwardly is in close contact with the trough 8 of the flexible tube 2, it can be easily sealed with a one-touch operation by simply inserting the flexible tube 2. can do.

  The flexible pipe joint sealing structure according to claim 2 has a large-diameter hole 13 having a female thread 12 formed on the inner periphery at the large-diameter side end of the tapered surface 10 in the joint body 5 as described in claim 3. It is formed in a communication shape, and the tip end portion of the presser wheel 14 is screwed into the large-diameter hole 13, and an annular shape that fits on the outer periphery of the flexible tube 2 between the tip end portion of the presser wheel 14 and the rear end portion of the rubber seal 6. The fireproof packing 15 and the retaining ring 16 whose inner diameter portion engages with the valley portion 8 of the flexible tube 2 can be accommodated. According to this, the flexible pipe 2 can be connected to the joint body 5 in a retaining shape by the retaining ring 16 and in a fireproof seal shape by the fireproof packing 15.

  According to the present invention, it is possible to connect in a seal shape by a one-touch operation by simply inserting the flexible pipe, and at least the slope of the valley of the flexible pipe is sealed with a rubber seal, thereby affecting the deformation of the flexible pipe, bending after construction, etc. There is an advantage that it is difficult to receive and can improve the sealing performance.

  Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a half cutaway sectional view showing a flexible pipe joint according to an embodiment of the present invention in a state before insertion of the flexible pipe, and FIG. FIG. 3 is a cutaway sectional view of the flexible pipe joint shown in the middle of insertion of the flexible pipe, and FIG. 4 is a half cutaway sectional view of the flexible pipe joint shown in the state after completion of insertion of the flexible pipe.

  As shown in FIG. 4, the seal structure of the flexible pipe joint 1 is formed with a receiving part 3 for receiving the tip part of the metal flexible pipe 2 at one end part and a male screw 4 for connection on the outer periphery of the other end part. The joint body 5 and the rubber seal 6 accommodated in the receiving portion 3 of the joint body 5 are provided.

  The flexible tube 2 has crest portions 7 and trough portions 8 that extend in the circumferential direction on the outer peripheral portion thereof alternately in the tube axis direction, and the outer periphery thereof is covered with a synthetic resin layer 9 such as vinyl chloride. .

  In the joint body 5, a tapered surface 10 is formed on the inner periphery of the receiving portion 3 so as to be narrowed toward the inner side of the receiving portion 3, and a small-diameter hole 11 is formed in communication with the small-diameter side end of the tapered surface 10. .

The rubber seal 6 is made of NBR, SBR, EPDM, etc., and has a peripheral wall 6a, an annular first protrusion 6b projecting inwardly at the inner periphery of the tip of the peripheral wall 6a, and an outer periphery of the rear end of the peripheral wall 6a. It is formed in a cylindrical shape having an annular second protrusion 6c projecting in the direction.
As shown in FIG. 1, the rubber seal 6 has a small-diameter hole 11 so that the outer periphery of the second protrusion 6 c abuts against the tapered surface 10 and the peripheral wall 6 a is positioned in the small-diameter hole 11 before the flexible tube 2 is inserted. It is housed and arranged inside. The first projecting portion 6b is formed in a circular shape as shown in FIG. 1 or a quadrangle as shown in FIG. 5 so that the tip of the flexible tube 2 inserted into the receiving portion 3 can be reliably received. The As shown in FIG. 3, when the flexible tube 2 is inserted, the second protrusion 6c is slidably contacted with the tapered surface 10 when the rubber seal 6 moves in the interior of the receiving portion together with the flexible tube 2. 10 is subjected to a pressure reduction deformation inward by receiving a pressing force, and the cross-sectional shape thereof is a circle that linearly contacts the tapered surface 10 as shown in FIG. 1 or a part of its circumference as shown in FIG. It is formed in a flat circular shape or the like having a flat surface 6 d in surface contact with the tapered surface 10.

  When the flexible tube 2 is inserted into the receiving port 3 as shown in FIG. 2, the rubber seal 6 is externally fitted to the flexible tube 2 as shown in FIG. The first protrusion 6b is received and pushed into the small-diameter hole 11, and the second protrusion 6c is slidably contacted with the tapered surface 10 and deformed inwardly by the pushing, so that the slope 8a of the valley portion 8 of the flexible tube 2 is deformed. And at least one of the valley bottom portion 8b and at least the inclined surface 8a are brought into close contact with each other. Thereby, the space between the distal end portion of the flexible tube 2 and the outer peripheral surface in the vicinity of the distal end portion and the inner peripheral surface of the small-diameter hole 11 of the joint body 5 is surely hermetically sealed, and the fluid flowing in the flexible tube 2 flows. The state which can prevent leaking through between the front-end | tip outer periphery of the flexible tube 2 and the inner periphery of the small diameter hole 11 from a part is obtained.

  In the rubber seal 6, if the second protrusion 6c is formed inward in the same manner as the first protrusion 6b from the beginning, the second protrusion 6c becomes an insertion obstacle when the flexible tube 2 is inserted. At the beginning, that is, at the stage before inserting the flexible tube, the two projecting portions 6b protrude outwardly as shown in FIG. 1, and the second projecting portion 6b becomes an insertion obstacle when the flexible tube 2 is inserted. The tip of the flexible tube 2 can be inserted into the rubber seal 6 smoothly.

  A large-diameter hole 13 having a female thread 12 formed on the inner periphery is formed in a continuous manner at the large-diameter side end of the tapered surface 10 in the joint body 5, and the female thread 12 of the large-diameter hole 13 is connected to the tip of the push ring 14. The pusher wheel 14 is screwed into the large-diameter hole 13 by screwing a male screw 14 a provided on the outer periphery. An outwardly expanding tapered surface 14 b is provided on the inner periphery of the tip end portion of the press wheel 14. An annular fireproof packing 15 and a retaining ring 16 are accommodated between the front end of the pusher wheel 14 and the rear end of the rubber seal 6. A circumferential groove 17 is formed on the inner periphery of the push ring 14, and a waterproof packing 18 made of EPDM or the like is fitted into the circumferential groove 17. In addition, an inner cylinder 19 having an outer diameter smaller than the inner diameter of the flexible tube 2 is formed concentrically and integrally protruding from the inner wall of the joint body 5 in the small diameter hole 11 in the joint body 5. A space 20 is formed between the outer periphery of the inner cylinder 19 and the inner periphery of the small diameter hole 11 so that the tip of the flexible tube 2 is introduced together with the rubber seal 6.

  Next, a sealing method for connecting the flexible pipe 2 to the flexible pipe joint 1 in a sealing manner will be described with reference to FIGS.

  First, as shown in FIG. 2, the flexible pipe 2 from which the synthetic resin layer 9 has been peeled and about six ridges 7 are exposed is connected to the retaining ring 16 in the receiving portion 3 of the joint body 5 from the pusher wheel 14. The fireproof packing 15 and the rubber seal 6 are inserted in this order, and the tip of the flexible tube 2 is brought into contact with the first protrusion 6 b of the rubber seal 6.

  Subsequently, as shown in FIG. 3, when the flexible tube 2 is inserted further deeply, the rubber seal 6 is pushed into the receiving portion in the back direction together with the flexible tube 2, and the second protrusion 6 c of the rubber seal 6 is tapered with the pushing. 10 slidably contacted to the narrowed side of the tape 10 and pressed by the taper surface 10 to reduce the diameter thereof inwardly. As soon as it passes through the taper surface 10, both the slope 8a and the valley bottom 8b of the valley 8 Or at least in close contact with the inclined surface 8a. As a result, the space between the outer peripheral surface of the distal end portion of the flexible tube 2 and the inner peripheral surface of the small-diameter hole 11 of the joint body 5 is surely hermetically sealed, and fluid flowing in the flexible tube 2 flows from the distal end portion of the flexible tube 2 to the flexible tube. The state which can prevent leaking through between the outer periphery of the front-end | tip part of 2 and the small hole 11 inner periphery of the coupling main body 5 is obtained. A sealing function can also be expected between the tip of the flexible tube 2 and the first protrusion 6b of the rubber seal 6.

  In the rubber seal 6, if the second protrusion 6c is formed so as to protrude inward in the same manner as the first protrusion 6b from the beginning, the distal end of the flexible pipe 2 is supported by the second protrusion 6c when inserted. Although it becomes an obstacle, since the second protrusion 6b protrudes outward before the flexible pipe is inserted, the flexible pipe 2 does not cause the second protrusion 6b to become an obstacle when the flexible pipe 2 is inserted. Can be smoothly inserted into the rubber seal 6.

  Further, by inserting the flexible tube 2 further deeply as shown in FIG. 3, the retaining ring 16 and the fireproof packing 15 also move in the interior of the receiving portion together with the flexible tube 2, so that the distal end of the retaining ring 16 and the push ring 14. A space S is formed between the two parts, and this space S is eliminated by tightening the push wheel 14 as shown in FIG. When the push ring 14 is tightened, the sealed state of the rubber seal 6 is reliably maintained. Further, as the push ring 14 is tightened, the retaining ring 16 comes close to and faces the tapered surface 14 b of the push ring 14 with the inner diameter portion 16 a engaged with the valley portion 8 of the flexible tube 2. Therefore, even if an external force is applied in the direction in which the flexible tube 2 is pulled out at this time, the retaining ring 16 that accompanies the flexible tube 2 contacts the constricted side of the tapered surface 14b, so that the retaining ring 16 is reduced in diameter. The inner diameter portion 16a of the lever increases the engagement force of the flexible tube 2 with the valley portion 8, so that the flexible tube 2 is reliably prevented from coming out.

  In the above embodiment, a large-diameter hole 13 having an internal thread 12 formed in the inner periphery is formed in a continuous manner at the large-diameter side end of the tapered surface in the joint body 5, and a pusher wheel 14 is screwed into the large-diameter hole 13. An annular fireproof packing 15 for fitting and sealing to the outer periphery of the flexible tube 2 inserted between the front end portion of the push ring 14 and the rear end portion of the rubber seal 6, and a flexible tube into which the inner diameter portion is inserted. 2, and a retaining ring 16 that engages with the trough 8 of the two to prevent the flexible tube 2 from being removed, but is limited to the fireproof sealing means by the fireproof packing 15 and the retaining means by the retaining ring 16. However, other fireproof sealing means and retaining means may be used. Further, it is not always necessary to incorporate the push ring 14, the fireproof sealing means, the retaining means and the like.

  Moreover, in the said Example, although the receptacle part 3 was formed in the one end of the coupling main body 5, and the male screw flexible pipe joint formed in the outer periphery of the other end was described, this invention is not limited to this, Needless to say, the present invention can also be applied to a structure, for example, a bilaterally symmetric socket-type joint for a flexible pipe having an opening at both ends, an elbow-type joint for a flexible pipe, and the like.

It is a half notched cross-sectional view showing the joint for flexible pipe showing an embodiment of the present invention in a state before insertion of the flexible pipe. It is a missing sectional view of the joint for flexible pipes shown in the state in the middle of flexible tube insertion. It is a missing sectional view of the joint for flexible pipes shown in the state in the middle of flexible tube insertion. FIG. 6 is a half-broken cross-sectional view of the flexible pipe joint shown in a state after completion of insertion of the flexible pipe. It is sectional drawing which shows the other Example of the rubber seal of the joint for flexible pipes. It is sectional drawing which shows other Example of the rubber seal of the joint for flexible pipes. It is a half notched cross-sectional view of the joint for flexible pipes of the conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Joint for flexible pipes 2 Flexible pipe 3 Receptacle part 5 Joint body 6 Rubber seal 6a Peripheral wall part 6b 1st protrusion part 6c 2nd protrusion part 7 Mountain part 8 Valley part 8a Slope 10 Tapered surface 11 Small diameter hole 13 Large diameter hole 14 Push ring 15 Fireproof packing 16 Retaining ring

Claims (3)

A distal end portion of a flexible pipe in which crests and troughs extending in the circumferential direction are arranged alternately in the pipe axis direction on the outer periphery of the receiving part of the joint body having a receiving part at one end. In the sealing method of the joint for flexible pipes inserted and sealed between the inner circumference of the receiving port and the outer circumference in the vicinity of the tip of the flexible pipe with a rubber seal,
The rubber seal includes a peripheral wall portion, an annular first protrusion projecting inwardly on the inner periphery of the distal end of the peripheral wall portion, and an annular second protrusion projecting outward on the outer periphery of the rear end portion of the peripheral wall portion. Is formed into a cylindrical shape having
A tapered surface is formed in the inner periphery of the receiving part so as to be narrowed toward the inner part of the receiving part, and a small-diameter hole is formed in a continuous shape at the small-diameter side end of the tapered surface,
The rubber seal is accommodated in the small-diameter hole so that the outer periphery of the second protrusion is in contact with the tapered surface,
As the distal end portion of the flexible tube is inserted into the receiving portion, the distal end portion is inserted into the rubber seal, abuts against the first protrusion, and the rubber seal is pushed inward in the receiving portion. Accordingly, the second projection is slidably contacted with the tapered side of the taper surface so that the diameter of the second projection is reduced inward so as to be in close contact with at least the slope of the valley of the flexible tube. How to seal the joint. A flexible pipe in which crests and troughs extending over the entire circumference in the circumferential direction are alternately arranged in the pipe axis direction, and a joint body having a receiving part for receiving the tip of the flexible pipe at one end; In the seal structure of the joint for flexible pipes, comprising a rubber seal that seals between the inner circumference of the receiving portion of the joint body and the outer circumference in the vicinity of the tip of the flexible pipe,
A tapered surface is formed in the inner periphery of the receiving part so as to be narrowed toward the inner part of the receiving part, and a small-diameter hole is formed in a communication manner at the small-diameter side end of the tapered surface,
A cylindrical shape having a peripheral wall, an annular first protrusion projecting inwardly on the inner periphery of the tip of the peripheral wall, and an annular second protrusion projecting outward on the outer periphery of the rear end of the peripheral wall The rubber seal formed on the outer periphery of the flexible tube is inserted in the vicinity of the distal end portion of the flexible tube inserted into the receiving portion, and the pressing action by the distal end portion of the flexible tube is received by the first protrusion into the small diameter hole. The flexible structure is characterized in that, while being pushed, the second protrusion, which is slidably in contact with the taper surface with the pushing and deformed inwardly, is in close contact with at least the slope of the valley of the flexible tube. Pipe joint seal structure. A large-diameter hole having a female thread on the inner periphery is formed in a continuous manner at the large-diameter side end of the tapered surface in the joint body, and the tip of the press ring is screwed into the large-diameter hole. An annular fireproof packing that fits to the outer periphery of the flexible pipe and a retaining ring whose inner diameter engages with the valley of the flexible pipe are accommodated between the front end and the rear end of the rubber seal. The seal structure for a flexible pipe joint according to claim 2.

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