JP6670194B2 - Fluid pipe separation prevention device and fluid pipe separation prevention method - Google Patents

Description

  The present invention relates to a device for preventing separation of a fluid pipe and a method for preventing separation of a fluid pipe using the same.

  At a connection point of a fluid pipe such as a water pipe, a detachment prevention device may be used for a pipe joint formed by inserting an insertion port of another pipe into a reception port of one pipe. Such a device for preventing detachment of a fluid pipe is applied to, for example, a press ring in a mechanical type pipe joint, a socket of a pipe in a slip-on type pipe joint, and a reinforcement fitting attached to an existing pipe joint.

  Patent Literature 1 describes a pressing ring in which a plurality of locking members are accommodated in accommodation grooves formed in an annular housing, and each of which is provided with a push bolt as a pressing member. According to this configuration, each of the locking members is locked to the outer peripheral surface of the insertion opening by operating the push bolt, and the insertion opening can be prevented from being detached from the receiving opening. Further, when the push bolt presses the inclined surface of the locking member, an external force (hereinafter referred to as “pull-out force”) in the direction of the tube axis for detaching the insertion port from the receiving port acts, the locking member is inserted by a wedge effect. It is strongly pressed toward the outer peripheral surface of the mouth, and can exert an excellent detachment prevention function.

  Conventionally, since a pressing member is provided in each of a plurality of locking members, the same number of pressing members as the locking members are required, and unless a mounting hole for inserting them is formed in the housing. However, the cost tends to increase. In particular, when the housing is formed of an undivided annular body, it is considered that the pressing member is indispensable to lock the locking member on the outer peripheral surface of the insertion opening because the diameter of the housing itself cannot be reduced.

  Further, in the configuration that exhibits the wedge effect, when a pulling force is applied, a force in a rotating direction acts on the locking member, so that a claw (front) formed on the front side where the outer diameter of the inclined surface increases. The claw tends to be pressed more strongly than the claw formed on the rear side (rear claw). Therefore, there is a possibility that the load is biased to the front nail, the front nail excessively bites into the tube, the front nail and the rear nail do not bite uniformly, and the detachment preventing function is not sufficiently exhibited. This problem has been pointed out in Patent Document 2 by the present applicant, and as a solution to this problem, the present inventor has proposed a structure in which a pressing surface that presses the inclined surface of the locking member is inclined. I have.

  Therefore, the present inventor has proposed a structure in which some locking members omit the pressing member and the pressing surface is inclined with respect to the inclined surface of the locking member in order to realize cost reduction and securing of the detachment prevention function. I arrived. FIG. 13 is an example of such a configuration, in which the inclined surface 8 a of the locking member 8 provided with no pressing member is pressed by the bottom surface 91 of the accommodation groove 9. The bottom surface 91, which is a pressing surface, is inclined with respect to the inclined surface 8a so that the load is not biased on the front claw 8b when a pulling force is applied. However, in this configuration, it has been found that the locking member 8 tends to be inclined as shown in FIG. 14 when the outer peripheral surface of the insertion opening 2 comes into contact with the claws 8b and 8c.

  In the state of FIG. 14, the locking member 8 is tilted so much that the front claw 8 b is further away from the outer peripheral surface of the insertion opening 2, so that not only the front claw 8 b does not lock but also the rear claw 8 c extends along the circumferential direction. Since it does not lock evenly, the function of preventing detachment cannot be sufficiently exhibited. The locking member provided with the pressing member is unlikely to be in such an inclined state, and even if it is inclined, it can be corrected to an appropriate posture by operating the pressing member. However, the locking member 8 omitting such a pressing member cannot cope with such a problem.

  Patent Literature 3 describes a pressing ring in which a pressing member is omitted in some of a plurality of locking members, but does not adopt a structure in which a pressing surface is inclined with respect to an inclined surface of the locking member. However, this does not suggest a solution to the above-mentioned problem caused by the inclination of the locking member.

JP 2013-167329 A JP 2012-215266 A Japanese Utility Model Publication No. 55-31338

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a fluid pipe detachment prevention device capable of securing a detachment prevention function while reducing cost, and a method of preventing a fluid pipe detachment using the same. It is in.

  The above object can be achieved by the present invention as described below. That is, the fluid pipe detachment prevention device according to the present invention is a fluid pipe detachment prevention device used for a pipe joint formed by inserting the insertion opening of the other pipe into the reception opening of one of the pipes. A housing formed of an annular body formed separately or integrally and externally fitted to the insertion port, a plurality of locking members for locking on an outer peripheral surface of the insertion port, And a receiving groove for receiving the plurality of locking members, wherein the locking member has an inclined surface whose outer diameter changes along a tube axis direction, and an outer diameter of the inclined surface increases. A front claw formed on the front side, and a rear claw formed on a rear side where the outer diameter of the inclined surface is reduced, the accommodation groove has a first bottom surface whose diameter increases toward the front side, A second bottom surface formed on the front side of the first bottom surface, wherein the second bottom surface extends parallel to the tube axis direction, Or the diameter is reduced toward the front side, or the diameter is increased toward the front side at an inclination angle smaller than the first bottom surface, and the first bottom surface is in contact with the rear side of the inclined surface. In a state where the first bottom surface is gradually separated from the inclined surface toward the front side, and the second bottom surface is in contact with the front side of the inclined surface, the front claw and the rear claw are separated from the accommodation groove. It is configured to project evenly.

  In this device, it is necessary to provide a pressing member such as a push bolt since the front claw and the rear claw of the locking member protrude from the storage groove in a state where the bottom surface of the storage groove is in contact with the inclined surface of the locking member. There is no. Therefore, the number of pressing members can be reduced as compared with the conventional case, and the processing for forming the mounting holes in the housing can be reduced, which contributes to cost reduction. In addition, by bringing the bottom surface of the accommodation groove into contact with the inclined surface of the locking member as described above, the locking member is prevented from being inclined (see FIG. 14). With the wedge effect, the front nail and the rear nail are made to bite evenly without biasing the load on the front nail, so that the detachment prevention function can be secured.

  The plurality of locking members include a first locking member provided with a pressing member inserted through a mounting hole of the housing, and a second locking member not provided with the pressing member. The first locking member can be moved in the radial direction of the tube by operating a member, and the first bottom surface and the second bottom surface are provided at a location where the second locking member is disposed in the accommodation groove. Is preferred. In this case, since the pressing member is provided on the first locking member, the first locking member moved toward the insertion opening by operating the pressing member can be locked on the outer peripheral surface of the insertion opening. Although the pressing member is not provided in the second locking member, the front claw and the rear claw are evenly projected from the accommodation groove in a state where the first bottom surface and the second bottom surface are in contact with the inclined surface, The two locking members can be locked to the outer peripheral surface of the insertion opening.

  Since the diameter of the housing made of an undivided annular body cannot be reduced, a pressing member is usually provided for each of the plurality of locking members. However, according to the fluid pipe detachment prevention device of the present invention, the front claw and the rear claw protrude from the accommodation groove evenly in a state where the first bottom surface and the second bottom surface are in contact with the inclined surface of the locking member. Therefore, there is no problem even if the housing is formed of an undivided annular body.

  A plurality of through-holes extending in the pipe axis direction may be formed at a plurality of locations in the pipe circumferential direction on the outer peripheral surface of the housing, and the total number of the plurality of locking members may be smaller than the number of the through-holes. Normally, a locking member is provided between a pair of through holes that are adjacent in the circumferential direction, so that the number of locking members is the same as that of the through holes. On the other hand, according to the above configuration, the number of components for the locking member can be reduced.

  Further, the method for preventing detachment of a fluid pipe according to the present invention is characterized in that a housing made of an annular body is formed separately or integrally with the insertion port of the other pipe by inserting the insertion port of the other pipe into the reception port of the other pipe. An external fitting step of externally fitting the insertion opening, and a locking step of locking a plurality of locking members housed in a housing groove opening toward the outer peripheral surface of the insertion opening to the outer peripheral surface of the insertion opening. The locking member has an inclined surface whose outer diameter changes along the tube axis direction, a front claw formed on the front side where the outer diameter of the inclined surface is increased, and an outer diameter of the inclined surface. Has a rear claw formed on the rear side where the size is reduced, and the housing groove has a first bottom surface whose diameter increases toward the front side, and a second bottom surface formed on the front side of the first bottom surface. In the locking step, the first bottom surface is brought forward toward the front while the first bottom surface is in contact with the rear side of the inclined surface. The front claw and the rear claw, which are gradually separated from the inclined surface and the second bottom surface is in contact with the front side of the inclined surface and protrude from the accommodation groove, are respectively provided on the outer peripheral surface of the insertion opening. Is to be locked.

  In this method, since the front claw and the rear claw of the locking member protrude from the storage groove in a state where the bottom surface of the storage groove is in contact with the inclined surface of the locking member, it is necessary to provide a pressing member such as a push bolt. There is no. Therefore, the number of pressing members can be reduced as compared with the conventional case, and the processing for forming the mounting holes in the housing can be reduced, which contributes to cost reduction. In addition, by bringing the bottom surface of the accommodation groove into contact with the inclined surface of the locking member as described above, the locking member is prevented from being inclined (see FIG. 14). With the wedge effect, the front nail and the rear nail are made to bite evenly without biasing the load on the front nail, so that the detachment prevention function can be secured.

Front view of a press wheel which is an example of a fluid pipe movement prevention device according to the present invention. AA sectional view of the pressing wheel in FIG. BB sectional view of the press wheel in FIG. CC sectional view of the pressing wheel in FIG. Cross section of the push wheel before mounting Sectional view for explaining an outer fitting step Sectional view for explaining the sealing process Sectional view of the press wheel when using sheet material Sectional view showing another shape of the bottom surface of the accommodation groove Sectional view showing another shape of the bottom surface of the accommodation groove Front view of a pressing wheel according to another embodiment Half cross-sectional view of a reinforcement fitting as an example of a fluid pipe movement prevention device according to the present invention. Sectional view for explaining a conventional structure in which a pressing surface is inclined with respect to an inclined surface of a locking member. FIG. 13 is a cross-sectional view for explaining a problem caused by the structure in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 4 show an example in which the fluid pipe detachment prevention device according to the present invention is applied to a pressing wheel. The press ring 3 is used for a pipe joint formed by inserting the insertion port 2 of the other pipe P2 into the receiving port 1 of one pipe P1. Each of the pipes P1 and P2 is a ductile cast iron pipe for waterworks buried underground. However, the present invention is not limited to this, and may be, for example, a steel pipe, a vinyl chloride pipe, a polyethylene pipe, a polyolefin pipe, or another fluid pipe. The fluid flowing inside the pipes P1 and P2 is not limited to tap water, but may be, for example, industrial water, sewage, gas, or a gas-liquid mixture of gas and liquid.

  Between the receiving port 1 and the insertion port 2 inserted therein, there is disposed an annular sealing material 4 for sealing the gap therebetween. At the end of the receiving port 1, an enlarged diameter portion 1a whose diameter is enlarged toward the end face and a flange portion 1b which extends outward in the pipe diameter direction are formed, and the sealing material 4 is pushed into the enlarged diameter portion 1a. ing. The pressing wheel 3 presses the sealing material 4 in the tube axis direction and pushes the sealing material 4 into the enlarged diameter portion 1a, whereby a sealed state is secured.

  The press wheel 3 includes a housing 30 that is fitted to the insertion port 2, a plurality of locking members that lock on the outer peripheral surface of the insertion port 2, and a housing groove 33 that stores the plurality of locking members. The housing 30 is formed of a non-divided annular body formed separately from the socket 1 and is provided integrally and continuously in the pipe circumferential direction. The inner diameter of the housing 30 is larger than the outer diameter of the insertion port 2 (the outer diameter of the pipe P2), and the tips (front claws, rear claws) of the locking members protruding from the accommodation groove 33 are locked on the outer peripheral surface of the insertion port 2. are doing. In the present embodiment, an example in which the plurality of locking members include the first locking member 31 provided with the push bolt 34 and the second locking member 32 not provided with the push bolt 34 is shown.

  On the outer peripheral surface of the housing 30, through holes 35 extending in the tube axis direction are formed at a plurality of positions (four positions in the example of FIG. 1) in the tube circumferential direction. As shown in FIG. 4, a fastener 36 composed of a bolt and a nut is mounted in the through hole 35 and the through hole of the flange portion 1b. Thus, the pressing ring 3 is fixed to the receiving port 1 and the centering (centering) of the pressing ring 3 with respect to the receiving port 1 is performed. Further, the seal member 4 can be pressed by operating the fastener 36 to move the pressing wheel 3 toward the receiving port 1.

  The accommodation groove 33 opens toward the outer peripheral surface of the insertion opening 2 and is formed on the inner peripheral surface of the housing 30. The accommodation groove 33 is formed as an annular groove extending continuously in the pipe circumferential direction, but a plurality of arc-shaped accommodation grooves may be formed intermittently. As shown in FIGS. 1 and 2, at the location where the first locking member 31 is provided, a mounting hole is provided so as to penetrate the bottom surface of the accommodation groove 33, and a pressing bolt 34 serving as a pressing member is provided in the mounting hole. It has been inserted. Further, as shown in FIGS. 1 and 3, such a mounting hole is not provided at a location where the second locking member 32 is provided.

  The pressing wheel 3 includes a plurality of (four in the example of FIG. 1) locking members including a first locking member 31 and a second locking member 32, which are arranged in a circumferential direction of the tube. It is housed in the housing groove 33. In the present embodiment, the total number of the plurality of locking members is four, two of which are first locking members 31, and the remaining two are second locking members 32. The first locking member 31 is disposed above and the second locking member 32 is disposed below. By locking each of these locking members to the outer peripheral surface of the insertion port 2, it is possible to prevent the insertion port 2 from being detached from the receiving port 1.

  The second locking member 32 includes an inclined surface 32a whose outer diameter changes along the tube axis direction, and a front claw 32b formed on the front side (the right side in FIG. 3) where the outer diameter of the inclined surface 32a increases. And a rear claw 32c formed on the rear side (the left side in FIG. 3) where the outer diameter of the inclined surface 32a is reduced. The inclined surface 32 a is formed by a flat surface, and is inclined in a direction in which the diameter increases toward the receiving port 1. The front claw 32b and the rear claw 32c are arranged at an interval from each other in the tube axis direction. Each of the front claw 32b and the rear claw 32c has a triangular cross section while being curved at the same curvature as the outer peripheral surface of the insertion opening 2. Is protruded from the inner peripheral surface.

  Similarly, the first locking member 31 has an inclined surface 31a, a front claw 31b, and a rear claw 31c. The first locking member 31 is formed of the same member as the second locking member 32, and they differ only in the manner in which they are combined with the housing 30. The push bolt 34 is provided only on the first locking member 31, and by operating this, the first locking member 31 can be moved in the pipe radial direction. Each of the first locking member 31 and the second locking member 32 is made of a robust material such as metal, and specifically, cast iron is exemplified.

  As shown in FIG. 2, the end surface of the push bolt 34 inclined in the same direction is in contact with the inclined surface 31 a of the first locking member 31. When an external force (hereinafter referred to as “pull-out force”) in the direction of the tube axis that causes the insertion opening 2 to be detached from the receiving opening 1, the first locking member 31 is strongly pressed toward the outer peripheral surface of the insertion opening 2 by the wedge effect, and the detachment occurs. The prevention function is enhanced. Further, the end surface of the push bolt 34 is inclined with respect to the inclined surface 31a so that the load is not biased to the front claw 31b when a pulling force is applied. The push bolt 34 has an end face gradually separated from the inclined face 31a toward the front side while making its end face contact (line contact) the rear side of the inclined face 31a.

  As shown in FIG. 3, the bottom surface of the accommodation groove 33 is in contact with the inclined surface 32a of the second locking member 32. The second locking member 32 is held in the accommodation groove 33 with the front claw 32b and the rear claw 32c protruding from the accommodation groove 33. As described above, in the pressing wheel 3, the pressing bolt 34 is not provided on the second locking member 32. Therefore, in contrast to the conventional case where the same number of pressing bolts as the locking members are required, in the pressing wheel 3, the number of the pressing bolts 34 is smaller than the number of the locking members. Further, at the place where the second locking member 32 is provided, no mounting hole for inserting the push bolt 34 is provided, and the formation of the mounting hole is omitted. Since the formation of the mounting hole, which is a screw hole, requires drilling and tapping, the omission of such a hole has a great effect on cost reduction.

  The accommodation groove 33 has a first bottom surface 33a whose diameter increases toward the front side and a second bottom surface 33b formed on the front side of the first bottom surface 33a, and these are in contact with the inclined surface 32a. That is, the first bottom surface 33a and the second bottom surface 33b are provided at the location where the second locking member 32 is provided in the accommodation groove 33. The second bottom surface 33b extends in parallel with the tube axis direction, but this diameter decreases toward the front side or expands toward the front side at a smaller inclination angle (angle with respect to the tube axis direction) than the first bottom surface 33a. It can be diameter. In any case, it is preferable that the first bottom surface 33a and the second bottom surface 33b form an obtuse angle, and that the bottom surface of the housing groove 33 be bent as a whole.

  The pressing wheel 3 is configured such that, while the first bottom surface 33a is in contact with the rear side of the inclined surface 32a, the first bottom surface 33a is gradually separated from the inclined surface 32a toward the front side, and the second bottom surface 33b is located forward of the inclined surface 32a. The front claw 32b and the rear claw 32c are configured to protrude evenly from the storage groove 33 in a state where the abutment is in contact with the front claw 32b. Here, "the front claws and the rear claws project equally" means that the protrusions (positions in the tube radial direction) of the claws are substantially the same, and there is no problem in locking them together. This includes the case where a slight difference in projection (for example, 1 mm or less, preferably 0.5 mm or less) occurs.

  In this configuration, since the second bottom surface 33b is in contact with the front side of the inclined surface 32a, when the outer peripheral surface of the insertion port 2 is brought into contact with the front claw 32b or the rear claw 32c, the second locking member 32 It does not become inclined (see FIG. 14). Moreover, since the first bottom surface 33a is in contact with the rear side of the inclined surface 32a as described above, when a pulling force is applied, the wedge effect is exerted and the load is not biased to the front claw 32b, and 32b and the rear claw 32c are evenly bitten, so that an excellent detachment prevention function can be secured.

  The inclination angle θ of the first bottom surface 33a with respect to the inclined surface 32a is preferably 1 degree or more, more preferably 2 degrees or more, and 3 degrees in order to prevent the load from being biased to the front claw 32b when a pulling force is applied. The above is more preferred. Is preferably 5 degrees or less, more preferably less than 5 degrees, and even more preferably 4 degrees or less from the viewpoint of appropriately pressing the second locking member 32 toward the insertion opening 2. As described above, the inclination angle θ is preferably 1 to 5 degrees.

  The first bottom surface 33a is in contact (line contact) with the rear edge of the inclined surface 32a. It is preferable that those contact points are located on the rear side of the rear claw 32c, whereby the pressing of the first bottom surface 33a inward in the tube radial direction is preferentially transmitted to the rear claw 32c, 32c is pressed more strongly than the front claw 32b. As a result, when a pulling force is applied, a state in which the load is not biased to the front claw 32b is appropriately obtained, and the front claw 32b and the rear claw 32c can be bitten into the outer peripheral surface of the insertion hole 2 in a well-balanced manner. .

  A movement allowance is provided in the accommodation groove 33 so that each locking member can move in the tube axis direction. Such a movement allowance helps to develop the wedge effect. Further, the front claw 32b and the rear claw 32c are configured to always protrude from the accommodation groove 33 regardless of the position of the second locking member 32 in the accommodation groove 33. As a result, the second locking member 32 is appropriately locked to the outer peripheral surface of the insertion opening 2, and the detachment prevention function can be properly secured. When the second locking member 32 moves rearward, the rear claw 32c further protrudes due to the wedge effect on the first bottom surface 33a, but the front claw 32b does not excessively protrude due to the second bottom surface 33b as described above. The front claws 32b and the rear claws 32c bite evenly in a balanced manner. Although not shown, between the side surface of each locking member and the wall surface of the accommodating groove 33, an elastic material for preventing the locking member from dropping is interposed, and they are compressed and deformed. Can be moved to

  At the location where the first locking member 31 is provided with the push bolt 34, the outer diameter of the housing 30 needs to be relatively large, but the location of the second locking member 32 where the push bolt 34 is not provided. Thus, the outer diameter of the housing 30 can be made relatively small. As described above, the outer diameter of the housing 30 is made smaller at the setting position of the second locking member 32 than at the setting position of the first locking member 31, and the volume of the housing 30 is reduced by that amount to reduce the cost. be able to.

  In this embodiment, as shown in FIGS. 1 and 4, the distal end of the first locking member 31 or the second locking member 32 and the first locking member 31 or the second locking member 32 The tip and the pipe overlap each other in the pipe axis direction, and the region where the locking member contacts the outer peripheral surface of the insertion opening 2 is configured to be continuous in the pipe circumferential direction. The configuration of such a locking member is disclosed, for example, in Japanese Patent Application Laid-Open No. 2008-309186 by the present applicant. However, the present invention is not limited to this.

  When the first locking member 31 and the second locking member 32 coexist as in the present embodiment, the total number of the plurality of locking members is set to 4 or more, and one or two of them are replaced by the second locking member 32. Is preferable. Thereby, the ratio of the second locking member 32 is appropriately suppressed, and the contact balance of each locking member with the outer peripheral surface of the insertion opening 2 is improved. In particular, when the housing 30 is formed of a non-divided annular body, if the number of the second locking members 32 increases, it becomes difficult for the respective locking members to make contact with good balance. Therefore, one or two second locking members 32 are desirable. . When there are a plurality of second locking members 32, they are preferably arranged adjacent to each other.

  A method for preventing the detachment of the fluid pipe using the pressing wheel 3 will be described. The push wheel 3 in FIG. 5 shows an initial state such as at the time of shipping and transportation or at the start of an external fitting operation, and the housing 30 has not yet been fitted over the insertion opening 2 yet. The second locking member 32 is held in the accommodation groove 33 via the elastic material with the front claw 32b and the rear claw 32c protruding. First, the housing 30 is externally fitted to the insertion opening 2 as shown in FIG. 6 using this pressing wheel 3 (external fitting step). Next, as shown in FIG. 7, the sealing member 4 interposed in the gap between the receiving port 1 and the insertion port 2 is pressed to be in a sealed state, and the pressing ring 3 is fixed to the receiving port 1 (sealing step). Then, as shown in FIGS. 1 to 4, each locking member is locked to the outer peripheral surface of the insertion opening 2 (locking step).

  In the outer fitting step, the second locking member 32 is disposed below while the first locking member 31 is disposed above (see FIG. 1). Then, the housing 30 that is eccentric downward with respect to the insertion opening 2 is fitted outside the insertion opening 2 without causing the distal end of the first locking member 31 disposed above to protrude from the housing groove 33. At this time, the center of the housing 30 can be positioned lower than the center of the insertion port 2 by depositing the pressing wheel 3 in the insertion port 2 whose tube axis direction is oriented horizontally. Since the outer peripheral surface of the insertion port 2 is coated with an anticorrosive paint or the like, it is useful to prevent the outer peripheral surface of the insertion port 2 from being damaged in this way.

  FIG. 8 shows an example in which the second locking member 32 before being locked to the outer peripheral surface of the insertion opening 2 is covered with the sheet material 5. The sheet member 5 is provided only on the second locking member 32 of the first locking member 31 and the second locking member 32, and is arranged so as to close the opening of the accommodation groove 33. In the external fitting step, by covering the second locking member 32 with the sheet material 5 in this manner, it is possible to more reliably prevent the front claw 32b and the rear claw 32c from damaging the outer peripheral surface of the insertion opening 2. However, the use of the sheet material 5 is not essential. The sheet material 5 is preferably made of a soft material having weather resistance.

  In the sealing step, after the fastener 36 is attached to the flange portion 1b and the housing 30, the pressing ring 3 is moved toward the receiving port 1 by operating the fastener 36, and the sealing material 4 is pressed. By mounting the fastener 36, centering of the receiving port 1 and the pressing wheel 3 is performed, and centering of the insertion port 2 inserted into the receiving port 1 is also performed. Accordingly, the front claw 32b and the rear claw 32c of the second locking member 32 projecting from the accommodation groove 33 are locked to the outer peripheral surface of the insertion opening 2, respectively. When the sheet material 5 is used, the sheet material 5 is cut by locking the front claw 32b and the rear claw 32c.

  In the locking step, the first bottom surface 33a is gradually separated from the inclined surface 32a toward the front while the first bottom surface 33a is in contact with the rear side of the inclined surface 32a, and the second bottom surface 33b is The front claw 32b and the rear claw 32c protruding from the housing groove 33 are engaged with the outer peripheral surface of the insertion opening 2, respectively. Thus, when the outer peripheral surface of the insertion opening 2 comes into contact with the front claws 32b and the rear claws 32c, the second locking member 32 does not become inclined (see FIG. 14).

  By moving the first locking member 31 toward the insertion opening 2 by operating the push bolt 34, the front claw 31 b and the rear claw 31 c are locked on the outer peripheral surface of the insertion opening 2, respectively. In the present embodiment, the first locking member 31 is arranged only on the half circumference (upper half circumference) of the housing 30, and two or three (two in this embodiment) are provided on the remaining half circumference (lower half circumference) of the housing 30. Since the second locking member 32 is arranged, it is not necessary to operate the push bolt 34 on the half circumference of the housing 30. Eliminating the operation of the push bolt 34 at the lower part simplifies the operation as compared with the related art, and is particularly useful for construction in an excavation trench.

  In the present embodiment, since the second bottom surface 33b extends in parallel with the pipe axis direction, the posture of the second locking member 32 is easily stabilized, and the locking by the rear claw 32c is strengthened when a pulling force is applied. Can be As shown in FIG. 9, when the second bottom surface 33b is reduced in diameter toward the front side, the locking by the rear claw 32c is further strengthened. As shown in FIG. 10, in the shape in which the second bottom surface 33b is increased in diameter toward the front side at a smaller inclination angle than the first bottom surface 33a, the locking by the front claw 32b is effective although not so much as the rear claw 32c. In this way, by adjusting the angle of the second bottom surface 33b, the balance of the engagement between the front claw 32b and the rear claw 32c can be adjusted.

  The pressing wheel shown in FIG. 11 has the same configuration as the above-described pressing wheel 3 except for the structure relating to the locking member and the pressing bolt. In each of these press rings, through holes extending in the tube axis direction are formed at a plurality of positions (six positions in the present embodiment) in the tube circumferential direction on the outer peripheral surface of the housing, and a plurality of locking members are provided. The total number is smaller than the number of through holes. The locking member and the locking member adjacent to the locking member are arranged such that their tips overlap each other in the tube axis direction.

  In the example of (a), the number of locking members differs between the half circumference (upper half circumference) and the remaining half circumference (lower half circumference) of the housing, and the lengths of the first locking member and the second locking member also differ. I have. The number of through-holes is 6, which is originally a structure in which six locking members are arranged. However, the use of a second locking member that is long in the circumferential direction reduces the number of parts compared to the past. is made of. In the example of (b), in the structure of the above (a), the first locking member arranged on the upper half circumference is also formed long to further reduce the number of components. Further, an attachment hole is provided near the through hole in which the fastener is mounted so that the central portion of the first locking member can be pressed by the push bolt. In this configuration, since the lengths of the locking members are equal, the load balance is better than that of the structure (a). In the example of (c), the structure of (b) is further modified, and two push bolts are provided for one first locking member. Although the cost reduction effect is inferior to the structure of the above (b), the strength is excellent because there are many places for supporting the load.

  The pressing wheel shown in FIG. 11 is also configured so that the bottom surface of the housing groove is brought into contact with the inclined surface of the locking member, as described above, so that the above-described advantageous effects can be obtained.

  FIG. 12 shows an example in which the fluid pipe detachment prevention device according to the present invention is applied to a reinforcing bracket. Other than the configuration described below, the configuration can be the same as that of the above-described embodiment of the pressing wheel. The reinforcing metal fitting 6 is used for a pipe joint in which the insertion port of the other pipe P4 is inserted into the reception port of one pipe P3, and prevents the insertion port from being detached from the reception port. The space between the receiving opening and the insertion opening is sealed by a sealing material 40. The housing 60 is formed of a divided annular body formed separately from the socket of the pipe P3, and is configured to be able to be externally fitted to the insertion opening of the pipe P4 in the existing pipe joint. This pipe joint is a slip-on type, but may be a mechanical type.

  The structure of the bottom surface of the housing groove 63 of the housing 60 and the structure of the locking member 72 housed in the housing groove 63 are the same as those of the above-described example of the press wheel 3. That is, while the first bottom surface 63a is in contact with the rear side of the inclined surface 72a, the first bottom surface 63a is gradually separated from the inclined surface 72a toward the front side, and the second bottom surface 63b is in contact with the front side of the inclined surface 72a. The front claw 72b and the rear claw 72c are configured to evenly protrude from the accommodation groove 63 in the contact state. With such a configuration, the advantageous effects described above can be obtained.

  The housing 60 has a split structure (for example, a split structure) having split portions at a plurality of locations in the pipe circumferential direction, and the split portions are connected by a connecting tool (not shown). Since the diameter of the housing 60 can be reduced by tightening the connecting member, all the locking members housed in the housing groove 63 may be locking members provided with no pressing member. That is, the plurality of locking members accommodated in the accommodation groove 63 may be constituted only by the engagement member 72 pressed by the bottom surface of the accommodation groove 63 instead of the push bolt as shown in FIG.

  The present invention is not limited to the above-described embodiment at all, and various improvements and modifications can be made without departing from the spirit of the present invention. Can be appropriately changed according to the conditions.

  In the above-described embodiment, an example in which the fluid pipe detachment prevention device is applied to a press ring or a reinforcing metal fitting is shown. However, the present invention is not limited to this, and may be applied to a pipe socket in a slip-on type pipe joint, for example. Is also possible. In that case, the housing is formed of an undivided annular body formed integrally with the receiving port, and a plurality of locking members are housed in housing grooves formed on the inner peripheral surface thereof.

1 Receiving port 2 Insertion port 3 Pressing wheel (an example of a device to prevent detachment)
4 Sealing material 5 Sheet material 6 Reinforcement metal fittings (an example of a separation prevention device)
30 housing 31 locking member (first locking member)
32 Locking member (second locking member)
32a Inclined surface 32b Front claw 32c Rear claw 33 Housing groove 33a First bottom surface 33b Second bottom surface 34 Push bolt (press member)
60 housing 63 receiving groove 63a first bottom surface 63b second bottom surface 72 locking member 72a inclined surface 72b front claw 72c rear claw P1 tube P2 tube

Claims (5)

In a device for preventing detachment of a fluid pipe used in a pipe joint obtained by inserting an insertion port of another pipe into a reception port of one pipe,
A housing made of an annular body formed separately or integrally with the receiving port, and externally fitted to the insertion port;
A plurality of locking members for locking to the outer peripheral surface of the insertion opening,
An accommodation groove that opens toward the outer peripheral surface of the insertion opening and accommodates the plurality of locking members,
The locking member has an inclined surface whose outer diameter changes along the tube axis direction, a front claw formed on the front side where the outer diameter of the inclined surface increases, and a rear surface where the outer diameter of the inclined surface decreases. With a rear claw formed on the side,
The accommodation groove has a first bottom surface whose diameter increases toward the front side, and a second bottom surface formed on the front side of the first bottom surface,
The second bottom surface extends parallel to the pipe axis direction, or has a diameter reduced toward the front side, or has a diameter increased toward the front side at a smaller inclination angle than the first bottom surface,
While the first bottom surface is in contact with the rear side of the inclined surface, the first bottom surface is gradually separated from the inclined surface toward the front side, and the second bottom surface is in contact with the front side of the inclined surface. The detachment prevention device for a fluid pipe, wherein the front claw and the rear claw are configured to protrude evenly from the accommodation groove in the state. The plurality of locking members include a first locking member provided with a pressing member inserted through the mounting hole of the housing, and a second locking member not provided with the pressing member,
By operating the pressing member, the first locking member can be moved in the pipe radial direction,
2. The detachment prevention device for a fluid pipe according to claim 1, wherein the first bottom surface and the second bottom surface are provided at a location where the second locking member is provided in the accommodation groove. 3.   3. The device according to claim 1, wherein the housing is formed of an undivided annular body.   A plurality of through holes extending in the tube axis direction are formed at a plurality of locations in the circumferential direction on the outer peripheral surface of the housing, and the total number of the plurality of locking members is smaller than the number of the through holes. 3. The device for preventing separation of a fluid pipe according to claim 3. An outer fitting step of inserting an insertion opening of the other pipe into a reception opening of one pipe, and externally fitting the housing made of an annular body formed separately or integrally with the insertion opening to the insertion opening,
A locking step of locking a plurality of locking members housed in a housing groove opening toward the outer peripheral surface of the insertion opening to the outer peripheral surface of the insertion opening,
The locking member has an inclined surface whose outer diameter changes along the tube axis direction, a front claw formed on the front side where the outer diameter of the inclined surface increases, and a rear surface where the outer diameter of the inclined surface decreases. With a rear claw formed on the side,
The accommodation groove has a first bottom surface whose diameter increases toward the front side, and a second bottom surface formed on the front side of the first bottom surface,
In the locking step, while the first bottom surface is in contact with the rear side of the inclined surface, the first bottom surface is gradually separated from the inclined surface toward the front side, and the second bottom surface is the inclined surface. A method for preventing a fluid pipe from being detached in a state where the fluid pipe is brought into contact with a front side of the housing and the front claw and the rear claw protruding from the accommodation groove are respectively engaged with the outer peripheral surface of the insertion opening.

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