JP2018034171A - Metal pipe expansion tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable compression by man power and to achieve miniaturization and light weight in an expansion tool for expanding a pipe by compressing and deforming pipe expansion rubber fitted in near the end of a metal pipe.SOLUTION: An adaptor 23 in which the end 51 of a metal pipe 5 is fitted is provided with a recess 233 that has a side surface 234 corresponding to a part to be expanded and a bottom 236 against which the end 51 abuts, and a press ring 26 is screwed into and fixed to a shaft 25 that moves back and forth in a body 22 in which the adaptor 23 is set. The center 263 of the press ring 26 is covered with expansion rubber 21, and expansion rubber 21 is held between the other end 264 of a large diameter and the bottom 236 to be compressed. The shaft 25 is moved back and forth through rotation of a drive shaft 24 engaged therewith. Thus, as a screwing-in force into the shaft 25 of the drive shaft 24 is used for compressing the expansion rubber 21, man-power compression is enabled by holding a grip 33 through rotation by a handle 34. Thus, miniaturization and light weight can be achieved.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a pipe expanding tool for metal pipes such as thin stainless steel pipes.

  When connecting a metal pipe such as a thin stainless steel pipe to a valve, a joint, or the like, the vicinity of the end is plastically deformed from the inside, and the diameter is expanded into a knob shape or a flange shape. FIG. 3 is an example of the joint 6, and the metal tube 5 has a knob-like diameter-enlarged portion 52 formed in a portion that slightly enters from the end portion 51. As shown on the right side of FIG. 3, the male screw formed on the outer periphery of the joint 6 with the end portion 51 of the metal tube 5 and the openings 59 and 71 of the cap nut 7 facing the opening portion 61 of the joint 6. By fitting the female screw 72 of the cap nut 7 to 62, the joint 6 and the metal tube 5 are connected as shown on the left side of FIG.

  At the time of the connection, the inclined surface 521 on the rear side of the enlarged diameter portion 52 is pressed in the joint 6 direction by the guide slope 73 of the cap nut 7 so as to be fitted in advance inside the opening 61 of the joint 6. A front inclined surface 522 is pressure-bonded to the packing 8 and, if necessary, a disc spring 9 fitted on the outer periphery of the male screw 62 is interposed between the receiving surface 63 of the joint 6 and the tip 74 of the cap nut 7. The cap nut 7 is prevented from loosening with respect to the joint 6 by the pressure-bonding and reaction thereof, and fluid leakage from the connecting portion between the metal tube 5 and the joint 6 is prevented.

  And in order to implement | achieve such a connection structure, the patent document 1 is proposed as a tool which expands the said metal pipe 5. As shown in FIG. According to the prior art, a metal tube is fitted inside the flange having an enlarged diameter portion corresponding to the portion to be expanded on the inner peripheral surface, and the expanded rubber disposed inside the metal tube is pulled and compressed by a piston (shaft). Then, the metal tube is expanded by bulging in the radial direction and plastically deformed.

  In order to compress the expanded rubber and further expand and plastically deform the metal tube, a very large force is required to pull the piston (shaft). Therefore, in Patent Document 1, hydraulic pressure is used to drive the piston (shaft). In addition, electric tools are commercially available.

JP 2011-194438 A

  In the prior art, a hydraulic pressure or a motor is used to generate the large force, and there is a problem that the tool is large and the cost is increased. Therefore, although the prior art is suitable for processing a metal tube, it cannot be said to be suitable for a metal tube that does not require a large force for processing.

  An object of the present invention is to provide a metal tube expansion tool that can be made small and low in cost.

  A tube expansion tool for a metal tube according to the present invention is a tool for plastically deforming the vicinity of an end portion of a metal tube from the inside to expand the metal tube, and a cap including a cylindrical base portion and an end plate fitted into one end thereof. The end plate has a recess into which the end of the metal tube is fitted, and the bottom of the recess serves as a contact surface with which the end surface of the metal tube contacts, and the side surface of the recess Such an adapter, which becomes a slope corresponding to the part to be expanded, a cylindrical main body having an internal space communicating with the adapter, and inserted into the main body, is rotatable while being prevented from being displaced in the axial direction. A drive shaft that is supported on the other end and is driven to rotate by projecting to the opposite side of the adapter, and one end of the drive shaft is concentric with the drive shaft on the other end side of the drive shaft and the drive shaft is rotatable. The other end and the one A shaft that is prevented from rotating around the axis by the main body while being able to slide in the axial direction, and an opening formed at one end of the recess at the bottom of the end plate. A presser ring that is inserted and fixed to the other end portion of the shaft and the other end portion is enlarged in diameter, and is formed in an annular shape so as to cover one end portion side of the presser ring, and the bottom portion of the recess and the presser ring And a tube expansion rubber that expands the tube by being narrowed between the other end of the metal tube and expands the expanded portion of the metal tube.

  According to the above configuration, in connecting a metal pipe such as a thin stainless steel pipe to a valve, a joint, or the like, in the tool that plastically deforms the vicinity of the end of the metal pipe from the inside and expands the pipe, The radially expanded portion of the metal tube is expanded by compressing the internally expanded tube rubber in the axial direction and elastically deforming the expanded rubber. When the expanded rubber is compressed and expanded in diameter, a screwing force is used for compression to enable compression by human power.

  As a specific structure for this purpose, a cap-shaped adapter is provided, and in the end plate portion of the adapter, a recess into which the end of the metal tube is fitted from the outside is formed, while the main body on which the adapter is set One end of a presser ring inserted through the opening formed in the bottom of the recess is fixed to the shaft that advances and retracts inside, and the expanded rubber is covered on the one end before inserting the opening. Then, the expanded rubber is sandwiched between the other end of the holding ring whose diameter has been expanded and the bottom of the recess, and the expanded rubber is compressed / released by the advance and retreat of the shaft.

  The shaft is projected and retracted by rotation of a drive shaft which is connected to one end of the shaft and is rotatable to the main body and is prevented from being displaced in the axial direction. One end of the drive shaft opposite to the side connected to the shaft protrudes from the main body and is freely rotatable. The shaft has one end portion screwed to the drive shaft and the other end portion. The intermediate portion between the two is held by the main body so as to be capable of sliding in the axial direction while preventing rotation around the axis.

  Therefore, since the screwing force of the drive shaft into the shaft is used for compressing the tube expansion rubber, it is possible to compress the drive shaft manually by rotating one end of the drive shaft with a tool such as a ratchet wrench. Can do. This makes it possible to eliminate the need for a power source for the tool, to make the tool small and light and easy to carry, and to reduce the cost of the tool.

  In the metal tube expansion tool of the present invention, the adapter, the tube expansion rubber, and the presser ring are detachable from the main body, so that the diameter of the metal tube can be accommodated.

  According to said structure, it can respond to the diameter of several types of metal pipes, for example like a call 1 / 2B, 3 / 4B, 1B, only by replacing | exchanging an adapter, a presser ring, and tube expansion rubber at least. .

  Thereby, when dealing with the diameters of a plurality of types of metal pipes, parts other than those parts can be shared, and the cost and space of the tool can be further reduced.

  Furthermore, in the metal pipe expanding tool of the present invention, a rod-shaped grip extending in the radial direction is attached to the main body, and a rod-shaped handle extending in the radial direction is attached to one end portion of the drive shaft. The person grasps the grip and rotates the handle to slide the shaft.

  According to the above configuration, when a thin stainless steel pipe of about 0.3 ton is easy to be plastically deformed, that is, when the deformation force is small, the main body is provided with a grip to be held by an operator while preventing rotation. One end of the shaft is provided with a handle that can be rotated with a small force by the lever principle.

  Therefore, a tool for rotating the drive shaft such as the ratchet wrench is not required, and it is easier to carry.

  Further, in the metal tube expanding tool of the present invention, a needle roller that is rotatably supported while preventing displacement in the axial direction is interposed between the main body and the drive shaft. Between the two, a drive bush is provided which is rotatably supported while preventing displacement of the drive shaft in the radial direction.

  According to the above configuration, when supporting the drive shaft so as not to be displaced in the axial direction, it is a needle roller, and when supporting the drive shaft so as not to be displaced in the radial direction, with a drive bush (cylindrical oil-free bearing), Friction (necessary force) between the drive shaft and the main body can be reduced, and work by hand can be further facilitated.

  Furthermore, in the metal tube expanding tool of the present invention, one of the other end of the drive shaft and one end of the shaft is an outer cylinder, and the other is an inner cylinder that is screwed to the outer cylinder. A spiral groove is formed for a length corresponding to the crushing allowance of the expanded rubber, or the one outer cylinder side is formed hollow for a length corresponding to the crushing allowance for the expanded rubber, and beyond Is characterized by being formed solid.

  According to the above configuration, when the expanded rubber is crushed by a predetermined amount, and thus the diameter of the metal tube is expanded by an amount corresponding to the expanded portion of the cylindrical portion, the shaft penetrates into the drive shaft most deeply and is integrated. Since the rotation around the shaft axis is prevented, the rotation of the drive shaft is also prevented.

  Thereby, it is possible to prevent the tubular rubber from being crushed (expanded) excessively and damaging the tubular portion.

  As described above, the tube expansion tool for a metal pipe according to the present invention has a tube expansion rubber which is expanded in diameter by compressing and elastically deforming the tube expansion rubber fitted in the vicinity of the end of the metal tube in the axial direction. It uses the force of screwing to compress, and enables compression by human power.

  Therefore, compared to the conventional case of using a hydraulic pressure or a motor, the power source for the tool becomes unnecessary, the tool is small and light and easy to carry, and the cost of the tool can be expected to be reduced.

It is sectional drawing of the pipe expansion tool of the metal pipe which concerns on one Embodiment of this invention. It is sectional drawing which shows the mode of the final process of the metal pipe expanded with the said pipe expansion tool. It is sectional drawing of the junction part vicinity of a metal pipe and a coupling.

  FIG. 1 is a cross-sectional view of a metal tube expansion tool 1 according to an embodiment of the present invention. This pipe expanding tool 1 also has the above-mentioned patent in that the annular pipe expanding rubber 21 is compressed / released in the axial direction to deform, and the vicinity of the end 51 of the metal pipe 5 such as SUS is plastically deformed from the inside to expand the pipe. This is the same as Document 1. The tube expansion tool 1 of this embodiment includes the tube expansion rubber 21, the main body 22, the adapter 23, the drive shaft 24, the shaft 25, the presser ring 26, and drive bushes (cylindrical oil-free bearings) 27 and 28. A needle-shaped roller 30, a grip 33, and a handle.

  In the present embodiment, for example, adapters 23 corresponding to the diameter of the metal tube 5 such as calls 1 / 2B, 3 / 4B, and 1B are selectively attached to the main body 22. Yes. The adapter 23 is formed in a cap shape including a base portion 232 formed in a cylindrical shape and an end plate 231 that closes one end of the base portion 232. The end plate 231 has a recess 233 into which the end 51 of the metal tube 5 is fitted from the outside. The bottom portion 236 of the recess 233 serves as a contact surface with which the end surface 55 of the metal tube 5 contacts, and the side surface 234 corresponds to the portion to be expanded. In the example of FIG. 1, the side surface 234 is formed in a tapered shape whose inner diameter increases toward the opening end 235. The end plate 231 has an opening 237 at the center of the bottom 236 of the recess 233.

  The main body 22 includes a small-diameter portion 221 on the adapter 23 side, a large-diameter portion 222 connected to the small-diameter portion 221, and an end plate 224 that covers the open end 223 of the large-diameter portion 222. It communicates with the internal space 238 of the cap-shaped adapter 23. The cylindrical portion 2321 of the base portion 232 of the adapter 23 is fixed to the distal end portion 2211 of the small diameter portion 221. In the example of FIG. 1, the cylindrical portion 2321 is fitted to the outside of the cylindrical tip portion 2211, but the relationship between the inside and the outside may be reversed. As described above, the adapter 23 can be exchanged from the main body 22 in accordance with the diameter of the metal tube 5, so that the tip 2211 and the cylindrical portion 2321 are coupled by screwing or separately. It is only necessary to be exchangeable by being coupled using screws or the like.

  The end plate 224 covers the opening end 223 at the rear end of the main body 22 and has an opening 226 through which a drive shaft 24 described later is inserted. The end plate 224 is provided to prevent the drive shaft 24 and the shaft 25 from falling off from the main body 22, and since they correspond to the small-diameter metal tube 5 and are lightweight, the end plate 224 includes: This is realized by a simple configuration called a C-shaped ring that fits into a groove 227 formed on the inner periphery on the opening end 223 side. However, the end plate 224 may be fixed to the opening end 223 of the main body 22 by screwing, brazing, bonding, screwing, or the like.

  Inside the large-diameter portion 222 of the main body 22, a concave groove and a step portion are formed for appropriately positioning and housing the drive bushes 27 and 28 and the needle roller 30. The drive bushes 27 and 28 are smaller than the ball bearings and are cheaper and support the drive shaft 24 in a rotatable manner while preventing displacement of the drive shaft 24 in the radial direction. The needle-shaped roller 30 is also smaller than the thrust roller bearing, is less expensive, and is supported rotatably while preventing displacement of the drive shaft 24 in the axial direction. A washer 31 is interposed between the needle roller 30 and the large diameter portion 222 of the main body 22. After the drive shafts 24 and 28 are fitted to the large diameter portion 222, the needle rollers 30 are fitted to the drive shaft 24, and the washer 31 is fitted, the drive shaft 24 is fitted to the main body 22, and then the end plate 224 is It is inserted.

  One end 241 of the drive shaft 24 protrudes from the opening 226 of the end plate 224 as described above, and is formed in the shape of a hex nut in this embodiment. The shape of the one end 241 may be such that a tool such as a ratchet wrench that rotates the drive shaft 24 can be driven without slipping. The other end 242 of the drive shaft 24 is formed in a cylindrical shape, and a spiral female screw is formed therein.

  A male screw formed on the outer peripheral surface of the one end 251 of the shaft 25 is screwed into the female screw of the other end 242. It should be noted that the male and female screw relationship between the other end 242 of the drive shaft 24 and the one end 251 of the shaft 25 may be reversed. In the shaft 25, an intermediate portion 253 between the one end portion 251 and the other end portion 252 is formed in a polygon, for example, a square, and is inserted through the opening 227 of the small diameter portion 221. Accordingly, the shaft 25 is held by the main body 22 so as to be able to slide in the axial direction while being prevented from rotating about the axis. The drive shaft 24 and the shaft 25 are concentrically screwed with the shaft 25 so that the drive shaft 24 is rotatable.

  One end 262 of the presser ring 26 is fixed to the other end 252 of the shaft 25 by screwing. In the present embodiment, the tip 261 of the presser ring 26 is formed in the shape of a hexagon nut, the one end 262 is formed with a male screw on its outer peripheral surface, and the inner peripheral surface of the cylindrical other end 252 of the shaft 25. Are screwed into the female screw formed on the head. The center portion 263 of the presser ring 26 is inserted through the opening 237 formed in the bottom 236 of the recess 233 of the end plate 231, and the expanded rubber 21 is fitted on the outer peripheral surface thereof. The other end portion 264 of the presser ring 26 connected to the central portion 263 is enlarged in diameter and forms a step portion with the central portion 263. Therefore, the expanded rubber 21 can be sandwiched between the bottom 236 of the recess 233 of the end plate 231 and the other end 264 of the presser ring 26.

  According to the tube expansion tool 1 configured as described above, the tube expansion rubber 21 fitted in the vicinity of the end 51 of the thin metal tube 5 is compressed in the axial direction and elastically deformed to expand the diameter. When plastically deforming the vicinity of the end 51 from the inside and expanding the pipe, the force of screwing into the shaft 25 of the drive shaft 24 is used to compress the expanded rubber 21, so the hexagonal portion of the one end 241 of the drive shaft 24 Can be compressed manually by rotating it with a tool such as a ratchet wrench. Then, by reducing the angle of the thread of the connecting portion between the shaft 25 and the drive shaft 24, the drive shaft 24 has to be rotated a little more or less in order to move the shaft 25 back and forth. Can also be plastically deformed. In this way, compared to the conventional case of using hydraulics and motors, a tool that does not require a power source, a small and lightweight tool that is easy to carry, and a tube expansion tool that can be expected to reduce tool costs are realized. can do.

  Further, in the tube expansion tool 1 of the present embodiment, the adapter 23 is detachable from the main body 22, and the adapter 23 has a plurality of types of diameters of the recesses 233 according to the diameter of the metal tube 5. Corresponding to this, a plurality of types of tube expansion rubber 21 and presser ring 26 are also prepared. Therefore, it is possible to cope with the diameters of a plurality of types of metal pipes such as, for example, the calls 1 / 2B, 3 / 4B, and 1B, by simply replacing the adapter 23, the presser ring 26, and the tube expansion rubber 21. The remaining main body 22, drive shaft 24, shaft 25, drive bushes 27 and 28, needle rollers 30, etc. are shared to reduce the tool cost.

  Furthermore, in the tube expansion tool 1 of the present embodiment, one of the other end portion 242 of the drive shaft 24 and the one end portion 251 of the shaft 25 is an outer cylinder, and the other is an inner cylinder that is screwed thereto ( In the example of FIG. 1, the drive shaft 24 is an outer cylinder and the shaft 25 is an inner cylinder), and a helical groove for screwing is formed by a length H corresponding to the crushing allowance of the expanded rubber 21, or One outer cylinder side is formed hollow by a length H corresponding to the crushing allowance of the tube expansion rubber 21, and the distance beyond that is solid (in the example of FIG. 1, corresponding to the crushing allowance on the outer cylinder (242) side) A space for the inner cylinder (251) to enter the length H). By doing so, when the tube expansion rubber 21 is crushed by a predetermined amount and thus the diameter of the metal tube 5 is expanded by an amount corresponding to the side surface 234 of the recess 233 of the end plate 231, the shaft 25 penetrates the drive shaft 24 most deeply. Since the rotation about the axis of the shaft 25 is prevented, the rotation of the drive shaft 24 is also prevented. Accordingly, it is possible to prevent the tubular rubber 231 from being crushed (expanded) excessively and damaging the tubular portion 231.

  Here, FIG. 2 shows a state of the final processing of the metal pipe 5 expanded by the tube expansion tool 1. In the present embodiment, the end portion 51 of the metal tube 5 is expanded in diameter from the end surface 55 in the shape of a knob 53 as shown in FIGS. 2 (a) to 2 (b). Therefore, the end plate 231 of the adapter 23 is also recessed from the opening end 235 only by the side surface 234 and immediately becomes the bottom surface 236, and the metal tube 5 cannot be supported from the outside. For this reason, two pipe holding rubber rings 32 are fitted on the outer peripheral surface of the other end 264 of the presser ring 26 to which the metal tube 5 is fitted, with an interval in the axial direction. As a result, the metal tube 5 can be held without backlash. As shown in FIG. 2C, the end portion 51 of the metal tube 5 is finally formed in the flange 54 by crushing the portion of the knob 53 in the axial direction with another jig (not shown). The

  Further, in the tube expansion tool 1 of the present embodiment, a rod-like grip 33 extending in the radial direction is attached to the main body 22 by screwing, and a rod-like handle 34 extending in the radial direction is attached to the one end portion 241 side of the drive shaft 24. It is done. One end 241 of the drive shaft 24 is formed in a hexagonal shape as described above, and the handle 34 is inserted into a hole 244 formed on one diameter line inside the hexagonal portion. Both ends of the handle 34 are crushed by a press machine to prevent the handle 34 from coming off. Alternatively, both ends of the handle 34 may be secured by screwing with nuts 35 as shown in FIG. 1, and in this case, as with the grip 33, this handle may be used during carrying and storage. 34 can also be removed.

  With this configuration, the operator holds the grip 33 and uses the lever principle corresponding to the small-diameter metal tube 5, that is, utilizing the small force applied to the plastic deformation of the metal tube 5. By rotating the handle 34 with a small force, the shaft 25 can be slid and the metal tube 5 can be plastically deformed. Therefore, a tool for rotating the drive shaft 24 such as the ratchet wrench is not necessary, and it is easier to carry. Furthermore, since the grip 33 and the handle 34 protruding in the radial direction from the main body 22 are detachable, they are easy to carry and store.

DESCRIPTION OF SYMBOLS 1 Tube expansion tool 21 Tube expansion rubber 22 Main body 2211 Tip part 221 Small diameter part 222 Large diameter part 223 Open end 224 End plate 225 Internal space 226 Opening 227 Groove 23 Adapter 231 End plate 232 Base 2321 Cylindrical part 233 Recess 234 Side 235 Open end 236 Bottom portion 237 Opening portion 238 Internal space 24 Drive shaft 25 Shaft 251 One end portion 252 Other end portion 253 Intermediate portion 26 Press ring 261 Tip 262 One end portion 263 Central portion 264 Other end portion 27, 28 Drive sash 30 Needle-shaped roller 32 For holding pipe Rubber ring 33 Grip 34 Handle 35 Nut 5 Metal tube 51 End 52 Expanded diameter 521, 522 Inclined surface 53 Slope 54 Flange 55 End surface 59 Opening 61 Opening 62 Male screw 6 Joint 7 Cap nut 71 Opening 72 Female screw 8 Packing 9 Disc spring

Claims (5)

In the tool for expanding the metal tube by plastically deforming the vicinity of the end of the metal tube from the inside,
It is formed in a cap shape having a cylindrical base and an end plate fitted into one end thereof, and the end plate has a recess into which the end of the metal tube is fitted, and the bottom of the recess is the metal Such an adapter, wherein the end surface of the tube is a contact surface to contact, and the side surface of the recess is a slope corresponding to the portion to be expanded;
A cylindrical main body having an internal space communicating with the adapter;
A drive shaft that is inserted into the main body, is rotatably supported while preventing displacement in the axial direction, and has one end protruding to the opposite side of the adapter and driven to rotate;
One end of the drive shaft is concentric with the drive shaft on the other end side of the drive shaft, and the drive shaft is rotatably screwed. Between the other end and the one end is rotated about the axis of the main body. A shaft that is prevented from sliding and that is slidable in the axial direction;
A presser ring whose one end is fixed to the other end of the shaft through the opening formed in the bottom of the recess of the end plate, and whose other end is expanded in diameter,
It is formed in an annular shape and is placed on one end side of the presser ring, and the diameter is increased by narrowing the pressure between the bottom part of the recess and the other end part of the presser ring whose diameter is increased. A tube expansion tool for a metal tube, comprising a tube expansion rubber for expanding a tube expansion portion.   2. The metal tube expansion tool according to claim 1, wherein the adapter, the tube expansion rubber, and the presser ring are detachable from the main body, so that the adapter can correspond to the diameter of the metal tube. A rod-shaped grip extending in the radial direction is attached to the main body,
A rod-shaped handle extending in the radial direction is attached to one end of the drive shaft,
The metal pipe expansion tool according to claim 1 or 2, wherein an operator grips the grip and rotates the handle to slide the shaft. Between the main body and the drive shaft, a needle-shaped roller that supports the shaft while being displaced while preventing displacement in the axial direction is interposed,
The metal tube expansion tool according to claim 3, wherein a drive bush is interposed between the main body and the drive shaft so as to be rotatably supported while preventing displacement of the drive shaft in a radial direction. .   One of the other end portion of the drive shaft and the one end portion of the shaft is an outer cylinder, and the other is an inner cylinder that is screwed to the outer cylinder, and a spiral groove for the screwing is crushed of the expanded rubber. A length corresponding to a margin is formed, or the one outer cylinder side is formed hollow for a length corresponding to a crush margin of the expanded rubber, and a portion beyond that is solid. The pipe expansion tool of the metal pipe of any one of 1-4.

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