JP5459796B2 - Lock ring diameter expanding method and diameter expanding apparatus - Google Patents

Description

  The present invention provides a lock ring for preventing the insertion-side tube inserted into the receiving-side tube, and temporarily inserting the lock ring into a diameter-enlarged state when the insertion-side tube is inserted. The present invention relates to a lock ring diameter expanding method and a diameter expanding apparatus.

  Pipe joints such as ductile cast iron pipes used for water pipes, etc. are formed by forming a receiving port in the receiving side pipe body, forming an insertion port in the inserting side pipe body, and inserting them into each other. . In this pipe joint, in order to prevent the inserted pipes from coming off due to shaking such as an earthquake, a separation preventing mechanism may be provided.

  As an example of the separation preventing mechanism, as shown in FIG. 5, a lock ring groove 2 is formed in the inner periphery of the receiving port of the receiving tube 1, and a dividing portion 3 (cut) is formed in the lock ring groove 2 in the circumferential direction. The formed lock ring 4 is provided so as to be able to expand the diameter, and a protrusion 18 that protrudes in the outer diameter direction at the insertion port of the insertion side tube body 17 and has an outer diameter larger than the inner diameter of the lock ring 4 when the diameter is reduced. In some cases, the protrusion 18 is locked by the lock ring 4 so that the insertion-side tube 17 is prevented from coming off from the receiving-side tube 1.

  The protrusion 18 is formed with a taper 19 having a diameter that decreases toward the tip of the insertion opening, and a wall 20 that stands in the outer diameter direction is formed on the opposite side of the insertion opening of the protrusion 18. ing. On the other hand, the lock ring 4 is formed with a taper 5 whose diameter increases toward the receiving port side of the receiving tube 1, and a wall portion 6 standing in the inner diameter direction is formed on the back side of the receiving port. Has been.

  When the insertion tube 17 is inserted into the receiving tube 1, both the tapers 5 and 19 of the lock ring 4 and the projection 18 come into contact with each other, and the width of the divided portion 3 is expanded by the contact force. The inner diameter of the increases. Then, the protrusion 18 can pass through the inner diameter side of the lock ring 4, and the two pipe bodies 1 and 17 can be connected. The receiving tube 1 is provided with a watertight rubber ring 21, and a push ring 22 is provided so as to contact the watertight rubber ring 21. By tightening the nut 24 to the pusher 22 and the bolt 23 provided on the receiving flange 9 of the receiving tube 1, the watertight rubber ring 21 is pushed between the receiving tube 1 and the insertion tube 17. Watertightness between the tubes 1 and 17 is ensured.

  Although the pipes 1 and 17 can be connected in this way, when the lock ring 4 is expanded in diameter by the protrusion 18, a certain amount of insertion force is required to support the heavy insertion side pipe 17. However, when the insertion is performed, an accessory device such as a hydraulic device may be required. Therefore, for example, in Patent Document 1, the diameter of the lock ring 4 is expanded before the insertion-side tube 17 is inserted, and the insertion-side tube 17 can be easily inserted into the receiving-side tube 1. Such a connection method has been proposed.

  According to this connection method, a diameter expanding jig (enlarger) is applied to both end faces of the split part (split part) of the lock ring, and the diameter of the lock ring is expanded by expanding the split part with the diameter expanding jig. In this expanded state, a stopper (plate-shaped body) is interposed in the divided portion, and the expander is removed. Then, this stopper maintains the expanded diameter state. 6A and 6B, the diameter of the lock ring 4 is increased in the direction of the arrow shown in FIG. 6B using the lock ring diameter-expanding jig 25 shown in FIG. In addition, the diameter of the lock ring 4 can be maintained by extending the end of the stopper 26 to the end surface of the split portion 3 of the lock ring 4.

JP 2000-304176 A

  Since the diameter expansion jig 25 described in Patent Document 1 or FIGS. 6A and 6B is addressed to the end face of the split portion 3 of the lock ring 4, the catching area is small, and the diameter expansion jig 25 is slightly smaller. It is easy to cause troubles that come off the lock ring 4 just by shifting. Further, the diameter expansion jig 25 is provided with a handle 27 for performing a diameter expansion operation, and in order to operate the handle 27, a certain amount of space is required around it. However, in a small diameter pipe, it is often difficult to secure the space, or it is difficult to provide the diameter expansion jig 25 itself in the pipe.

  Therefore, an object of the present invention is to easily and surely perform the diameter expansion work of the lock ring regardless of the pipe diameter.

  In order to solve the above-mentioned problems, the present invention provides a lock ring groove formed on the inner periphery of the receiving tube with a lock ring formed with a split portion in the circumferential direction, and expands from the inner periphery side of the lock ring. The lock ring is expanded in diameter by pressing the tool, and a stopper is provided in the divided portion in this expanded state so that the expanded state of the lock ring is maintained even after the pressing by the expanded jig is released. The lock ring diameter increasing method was constructed.

  Since the inner peripheral surface of the lock ring is sufficiently wide compared to the end surface, even if the diameter expansion jig is slightly displaced when the diameter expansion jig is pressed to expand the diameter of the lock ring, the lock ring comes off the lock ring. Trouble is unlikely to occur. For this reason, the diameter expansion operation can be performed easily and reliably. Further, since this diameter expansion jig only needs to have a function of expanding the diameter of the lock ring, it is easy to reduce the size. For this reason, it can be applied to small diameter pipes without any problem. Further, by expanding the lock ring in advance with this diameter expansion jig, the insertion side tube can be easily inserted into the receiving side tube, and the insertion side tube can be directly inserted. As in the case of expanding the diameter of the lock ring, an auxiliary device such as a hydraulic device is not required.

  As the shape of the diameter expansion jig, it is particularly preferable to adopt a cylindrical or rod-like shape in which a taper having a smaller outer diameter is formed at the tip. If the taper and the inner periphery of the lock ring come into contact with each other when the diameter expanding jig is inserted into the receiving side tube, the inner periphery of the lock ring tapers as the amount of insertion of the diameter expanding jig becomes deeper. By sliding relatively upward, the diameter of the lock ring can be smoothly increased.

  The diameter expanding jig is not limited to a shape having a taper, and for example, a shape having a slit penetrating the inner and outer surfaces of the cylindrical body along the axial direction of the cylindrical member may be used. . The outer diameter of the cylindrical member is reduced by narrowing the width of the slit against the elastic force, and the cylindrical member is inserted into the receiving side tube body in the reduced diameter state. By expanding the diameter of the cylindrical member, it is possible to obtain the same lock ring diameter increasing effect as that of the diameter increasing jig having a taper.

  The width of the divided portion in a state where the diameter of the lock ring is expanded is substantially the same as the width of the stopper interposed in the divided portion. For this reason, the diameter expansion state of this lock ring is maintainable by interposing this stopper in a division part. The diameter expansion jig is removed from the receiving tube while the diameter expansion state is maintained by the stopper. And after this removal, it inserts in a receiving side pipe body, and inserts a side pipe body. At this time, since the diameter of the lock ring has already been expanded, the insertion work of the insertion side tube body into the receiving side tube body can be performed smoothly. By removing the stopper after this insertion work, the lock ring is reduced in diameter by its elasticity. Due to this diameter reduction, when a pulling force is applied to the insertion side tube body, the lock ring is brought into contact with the protrusion of the insertion side tube body to prevent the insertion side tube body from dropping off from the receiving side tube body. Can do.

  The lock ring diameter increasing device according to the above-mentioned lock ring diameter increasing method is provided in a lock ring groove formed in the inner periphery of the receiving side pipe body, and the lock ring having a circumferentially divided portion is removed from the inner periphery side. A diameter expansion jig that expands the diameter by pressing in the direction, and is provided in the divided portion of the lock ring in an expanded state, and when the pressing by the diameter expansion jig is released, the diameter expansion state of the lock ring And a stopper for maintaining. The functions of the diameter expanding jig and the stopper are as described above.

  According to the present invention, a diameter increasing jig is pressed from the inner peripheral side of the lock ring to increase the diameter of the lock ring, and in this expanded state, a stopper is provided in a divided portion formed in the circumferential direction of the lock ring, Even after the pressing by the jig is released, the diameter of the lock ring is maintained to be expanded. The outer diameter of the diameter expanding jig is appropriately determined in accordance with the inner diameter of the receiving tube, and can be applied regardless of the inner diameter of the receiving tube. Thus, the insertion work can be smoothly performed by inserting the side tube into the receiving tube with the diameter of the lock ring expanded.

In the lock ring diameter increasing method of the present invention, a state in which a diameter increasing jig is being inserted into the receiving tube is shown, (a) is a partial sectional view, and (b) is a partial sectional view of an essential part thereof. Following FIG. 1 a, a partial cross-sectional view showing a state where the insertion of the diameter expansion jig has been completed Following FIG. 1 b, a state in which a stopper is provided in the split part of the lock ring is shown, (a) is a partial sectional view, and (b) is a perspective view of the main part. FIG. 1C is a partial cross-sectional view showing a state in which the diameter expansion jig is being pulled out while maintaining the diameter expansion state of the lock ring. FIG. 1D is a partial cross-sectional view showing a state in which the extraction of the diameter expansion jig has been completed. FIG. 1E is a partial cross-sectional view showing a state where the insertion tube is inserted into the receiving tube. Following FIG. 1 f, a partial cross-sectional view showing a state where the stopper is removed. An example of the diameter expansion jig which concerns on this invention is shown, (a) is a front view, (b) is a side view, (c) is a perspective view. The stopper which concerns on this invention is shown, (a) is a front view, (b) is a side view, (c) is a rear view, (d) is a perspective view. Side view showing another example of the diameter expansion jig according to the present invention Partial cross-sectional view showing a connection configuration between tubular bodies having a detachment prevention mechanism The diameter expansion state using the lock ring diameter expansion jig which concerns on a prior art is shown, (a) is a fragmentary sectional view, (b) is a front view. Partial sectional view showing a state in which the diameter of the lock ring is maintained by a stopper in the prior art

  The connection procedure of the tubular bodies to which the lock ring diameter increasing method according to the present invention is applied is shown in FIGS. A lock ring groove 2 is formed on the inner periphery of the receiving port of the receiving tube 1, and a lock ring 4 having a split portion 3 formed in the circumferential direction is provided in the lock ring groove 2. As shown in FIG. 1 a, the lock ring 4 is formed with a taper 5 whose inner diameter increases toward the opening side of the receiving tube 1. In addition, a wall portion 6 is formed on the back side so as to stand toward the radially outer side of the tube shaft. On the opening side of the lock ring groove 2, a guide groove 7 is formed at a circumferential position corresponding to the split portion 3 of the lock ring 4. A stopper 8 described later is inserted through the guide groove 7. The lock ring 4 shown here is only an example, and other shapes can be used as long as the shape is obtained by forming the divided portions 3 in the circumferential direction. Further, if a gap for inserting the stopper 8 can be secured between the inner periphery of the receiving port of the receiving tube 1 and the diameter expansion jig 11 described later, the formation of the guide groove 7 is omitted. Can do.

  First, a feed screw 10 is provided on the receiving flange 9 of the receiving tube 1, and a diameter expansion jig 11 is provided on the feed screw 10. As shown in FIG. 2, the diameter expansion jig 11 has a substantially cylindrical shape with a tapered taper 12 formed at the tip. The diameter of the straight body 13 is smaller than the inner diameter of the receiving tube 1 so that the diameter-enlarging jig 11 can be freely inserted into the receiving tube 1. The feed screw 10 is provided with a feed nut 14 that feeds the diameter expansion jig 11 into the receiving tube 1 and a return nut 15 that pulls out the diameter expanding jig 11 inserted into the receiving tube 1. It has been.

  When the feed screw 10 is screwed and the diameter expanding jig 11 is inserted into the receiving tube 1, as shown in FIGS. 1 a (a) and (b), both the taper 5 of the lock ring 4 and the diameter expanding jig 11, 12 abuts. Due to this contact force, the diameter of the lock ring 4 is expanded. When the diameter is expanded, the entire inner circumference of the lock ring 4 is in contact with the taper 12 of the diameter expansion jig 11. The risk that the jig 11 will come off is low. For this reason, the diameter expansion operation | work of the lock ring 4 can be performed simply and reliably.

  As shown in FIG. 1b, when the diameter expanding jig 11 is inserted so that the straight body portion 13 of the diameter expanding jig 11 is positioned in the lock ring groove 2, the lock ring 4 is completely expanded in diameter. . In this expanded diameter state, the stopper 8 shown in FIG. 3 is inserted into the gap between the receiving tube 1 and the expanded diameter jig 11. The tip of the stopper 8 reaches the lock ring groove 2 through the guide groove 7 as shown in FIG. At this time, as shown in FIG. 1 c (b), the stopper 8 is along the outer peripheral surface of the diameter expanding jig 11, and the stepped portion 16 at the tip thereof is in contact with the end surface of the split portion 3 of the lock ring 4. In addition, in the same figure, description of the receiving side pipe body 1 etc. is abbreviate | omitted in order to make the said contact state easy to see.

  With the stopper 8 maintained in a state where the diameter of the lock ring 4 is expanded, the return nut 15 is screwed and the diameter expansion jig 11 inserted into the receiving tube 1 is pulled out as shown in FIGS. 1d and 1e. . Even in the state in which the diameter expanding jig 11 is pulled out, the stopper 8 is provided in contact with the end face of the divided portion 3, so that the diameter of the lock ring 4 is maintained.

  Further, with the diameter of the lock ring 4 expanded, the side tube 17 is inserted into the receiving tube 1 as shown in FIG. At the time of this insertion, the protrusion 18 formed at the tip of the insertion opening does not directly contact the lock ring 4, so that the insertion operation can be easily performed without using an accessory device such as a hydraulic device. After the insertion side tube body 17 is inserted, the stopper 8 is removed as shown in FIG. 1g. Then, the lock ring 4 whose diameter has been expanded by the stopper 8 is reduced to its original shape due to its elasticity, and its inner diameter becomes smaller than the outer diameter of the protrusion 18 of the insertion side tube body 17. Therefore, when a pulling force is applied to the insertion side tube body 17, the lock ring 4 and the protrusion 18 come into contact with each other, and the insertion side tube body 17 is prevented from falling off.

  In the above description of the connection procedure, the diameter expansion jig 11 corresponding to the receiving-side tube 1 having a specific inner diameter is used. However, as shown in FIG. 4, a plurality of tapers 12a, 12b, 12c having different outer diameters are used. In addition, the straight body portions 13a, 13b, and 13c may be formed coaxially so that one diameter expanding jig 11 can be applied to a plurality of receiving-side pipe bodies 1 having different inner diameters.

DESCRIPTION OF SYMBOLS 1 Receiving side pipe body 2 Lock ring groove 3 Dividing part 4 Lock ring 5 Taper 6 (Lock ring) Wall part 7 (Lock ring) Wall part 7 Guide groove 8 Stopper 9 Receptacle flange 10 Feed screw 11 Expanding jig 12 (Expanding diameter) Taper 13 Straight body portion 14 Feed nut 15 Return nut 16 Stepped portion 17 Insertion side tube 18 Projection portion 19 (Projection portion) Taper 20 (Projection portion) Wall portion 21 Watertight rubber ring 22 Push ring 23 Bolt 24 Nut 25 Diameter expansion jig 26 Stopper 27 Handle

Claims (2)

  The lock ring groove (2) formed on the inner periphery of the receiving tube (1) is provided with a lock ring (4) having a split portion (3) in the circumferential direction, and the inner periphery side of the lock ring (4). The diameter expansion jig (11) is pressed to expand the lock ring (4), and a stopper (8) is provided on the divided portion (3) in this diameter expansion state, and the diameter expansion jig (11) is used. A lock ring diameter increasing method in which the diameter of the lock ring (4) is maintained even after the pressing is released.   The lock ring (4) formed in the lock ring groove (2) formed on the inner periphery of the receiving tube (1) and having the divided portion (3) formed in the circumferential direction is pressed outward from the inner periphery side. A diameter expanding jig (11) that expands the diameter, and provided in the split portion (3) of the lock ring (4) in a diameter expanded state, when the pressing by the diameter expanding jig (11) is released A lock ring diameter increasing device comprising a stopper (8) that maintains the diameter expansion state of the lock ring (4).

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