Extension tools

Abstract

To provide an improved rotation mechanism of a jaw in a pipe expanding tool for expanding an end of a pipe.SOLUTION: The expanding tool has a wedge, a plurality of jaws, a spring, and a first rotary member. The wedge can be reciprocated along a first axis between a first position and a second position. The plurality of jaws are movable about the first axis to a closed position and an open position radially outward from the closed position, and are rotatable about the first axis. The plurality of jaws are configured to move from the closed position to the open position in response to movement of the wedge from the first position to the second position and to move from the open position to the closed position in response to movement of the wedge from the second position to the first position. The first rotary member is integrally rotatable with the plurality of jaws and engages the plurality of jaws. The first rotary member is configured to rotate in only one direction around the first axis by the elastic force of the spring.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] SUMMARY The present disclosure relates to a pipe expansion tool configured to expand an end of a pipe. [Background technology]

[0002] A tube expansion tool is configured to expand the end of a resin pipe (e.g., PEX (crosslinked polyethylene)) to enable connection of the pipe. The tube expansion tool includes a conical (tapered) wedge (also called a needle) that reciprocates in the axial direction, and a plurality of jaws (also called chucks) that are configured to expand the end of the pipe by moving radially outward in response to forward movement of the wedge. Also known is a tube expansion tool that includes a jaw rotation mechanism for changing the circumferential position of the jaws (see, for example, Patent Document 1). This rotation mechanism includes a cam that can move axially together with the needle, and a crown operably connected to the cam via a follower. The crown rotates around its axis together with the jaws in response to axial movement of the cam. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 7,922,475 Summary of the Invention [Problem to be solved by the invention]

[0004] In the jaw rotation mechanism configured as described above, even if the jaw becomes unable to rotate for some reason, an attempt is made to forcibly rotate the jaw, which places an excessive load on the rotation mechanism, which may result in damage to the rotation mechanism.

[0005] In view of the above circumstances, one non-limiting object of the present disclosure is to provide an improved jaw rotation mechanism in a pipe expansion tool for expanding the end of a pipe. [Means for solving the problem]

[0006] In one non-limiting embodiment of the present disclosure, the tube expansion tool includes a wedge, a plurality of jaws, a spring, and a first rotating member. The wedge is reciprocatable along a first axis between a first position and a second position. The plurality of jaws are movable relative to the first axis between a closed position and an open position radially outward from the closed position, and are rotatable about the first axis. The plurality of jaws are configured to move from the closed position to the open position in response to movement of the wedge from the first position to the second position, and to move from the open position to the closed position in response to movement of the wedge from the second position to the first position. The first rotating member is engaged with the plurality of jaws so as to be rotatable integrally with the plurality of jaws. The first rotating member is configured to rotate only in one direction about the first axis by the elastic force (elastic energy, restoring force) of the spring.

[0007] In the tube expanding tool of this embodiment, the first rotating member rotates due to the elastic force (elastic energy, restoring force) of the spring, thereby rotating the multiple jaws. Therefore, if the multiple jaws become unable to rotate for some reason, even if the first rotating member tries to rotate the multiple jaws, a force exceeding the elastic force of the spring will not be applied to the first rotating member. This effectively reduces the possibility of damage to the first rotating member due to excessive load being applied. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view of a tube expansion tool according to one embodiment of the present disclosure, showing a wedge in a first position and multiple jaws in a closed position; [Figure 2] FIG. 2 is a partially enlarged view of FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. [Figure 4] 1 is a perspective view of the wedge, the reciprocating mechanism, and the jaw rotation mechanism, showing the wedge in a first position. [Figure 5] 3 is a cross-sectional view corresponding to FIG. 2, showing the wedge in a second position and the jaws in an open position; [Figure 6] 4 is a cross-sectional view corresponding to FIG. 3, showing the wedge in a second position and the jaws in an open position; [Figure 7] 10 is a perspective view of the wedge, reciprocating mechanism, jaw rotation mechanism, and retaining sleeve, showing the wedge in a second position; FIG. [Figure 8] FIG. 2 is a perspective view of a jaw assembly. [Figure 9] FIG. 1 is an exploded perspective view of the jaw rotation mechanism (excluding the driven gear ring). [Figure 10] FIG. 10 is a perspective view of a second member of the rotary shaft. DETAILED DESCRIPTION OF THE INVENTION

[0009] In one non-limiting embodiment of the present disclosure, the first rotating member may be configured to rotate by the elastic force of a spring corresponding to at least a portion of the movement phase of the wedge from the second position to the first position. According to this embodiment, the multiple jaws rotate while returning from the open position to the closed position after expanding the end of the pipe, i.e., while moving in a direction away from the inner circumferential surface of the expanded pipe. This reduces the influence of the multiple jaws on the inner circumferential surface of the pipe, and the first rotating member allows the multiple jaws to rotate smoothly.

[0010] In addition to or instead of the above embodiment, the spring may be configured to accumulate elastic force corresponding to at least a portion of a movement phase of the wedge from the first position to the second position. The first rotating member may be configured to rotate by the elastic force accumulated in the spring corresponding to at least a portion of a movement phase of the wedge from the second position to the first position. According to this embodiment, the phase in which the spring accumulates elastic force (elastic energy) and the phase in which the first rotating member rotates the multiple jaws using the elastic force accumulated in the spring can be reasonably matched to the movement phase of the wedge.

[0011] In addition to or instead of the above embodiment, the tube expansion tool may further include a movable member operably coupled to the spring, configured to move in correspondence with at least a portion of the movement phase of the wedge from the first position to the second position, and configured to elastically deform the spring. According to this embodiment, the movable member can efficiently store elastic force in the spring.

[0012] In addition to or instead of the above embodiment, the tube expansion tool may further include a second rotating member and a transmission member. The second rotating member may be configured to rotate in a first direction about a second axis corresponding to at least a portion of the movement phase of the wedge from the first position to the second position, and to rotate in a second direction opposite to the first direction about the second axis by elastic force of a spring corresponding to at least a portion of the movement phase of the wedge from the second position to the first position. The transmission member may be operably coupled to the first rotating member and the second rotating member and configured to transmit only the rotation of the second rotating member in the second direction to the first rotating member. According to this embodiment, by using the second rotating member that can rotate in both directions about the second axis, a rational configuration can be realized in which the multiple jaws rotate only while the second rotating member rotates in the second direction by elastic force of the spring.

[0013] In addition to or instead of the above embodiment, the tube expansion tool may include a motion conversion mechanism operably coupled to the spring and the first rotating member and configured to convert linear motion into rotational motion. The motion conversion mechanism may be configured to be actuated by the elastic force of the spring in response to at least a portion of the movement phase of the wedge from the second position to the first position, thereby rotating the first rotating member. According to this embodiment, the elastic force of the spring is utilized to convert linear motion into rotational motion, thereby efficiently rotating the first rotating member and the multiple jaws.

[0014] In addition to or instead of the above embodiment, the motion conversion mechanism may include a fixed member and a second rotating member operably engaged with the fixed member via a cam portion. At least a portion of the second rotating member may be configured to rotate the first rotating member by moving along the second axis relative to the fixed member and rotating about the second axis. This embodiment makes it possible to realize a rational mechanism for converting linear motion into rotational motion.

[0015] In addition to or instead of the above embodiment, the spring may be a coil spring. Furthermore, the fixed member and the second rotating member may be at least partially housed inside the coil spring. According to this embodiment, the spring and the motion conversion mechanism can be accommodated in a relatively small space.

[0016] In addition to or instead of the above embodiment, the second rotating member may include a first portion and a second portion coupled to each other. The first portion and the second portion may be rotatable together around the second axis and movable relative to each other along the second axis. According to this embodiment, the first portion and the second portion can be rotated together by simply moving only one of the first portion and the second portion along the second axis.

[0017] In addition to or instead of the above embodiment, the first portion may be movable along a second axis relative to the fixed member and the second portion. Furthermore, the first portion may be configured to elastically deform the spring by moving along the second axis corresponding to at least a portion of the movement phase of the wedge from the first position to the second position. According to this embodiment, elastic force can be efficiently accumulated in the spring in response to the movement of the first portion.

[0018] A tube expansion tool 1 according to a representative but non-limiting embodiment of the present disclosure will be specifically described below with reference to the drawings. The tube expansion tool 1 is a power tool used to expand the end of a pipe (e.g., made of PEX (crosslinked polyethylene)) to enable the pipes to be connected.

[0019] First, the general configuration of the tube expanding tool 1 will be described.

[0020] As shown in FIG. 1, the tube expansion tool 1 mainly comprises an L-shaped housing 10, a jaw assembly 5 arranged at one end of the housing 10, a motor 20 housed within the housing 10, and a wedge 3 reciprocated by the motor 20.

[0021] The wedge 3 extends along the drive axis A1 within the housing 10. The tip of the wedge 3 protrudes into the jaw assembly 5 through an opening formed in the housing 10. The jaw assembly 5 is arranged around the wedge 3 and includes multiple jaws 51 that are movable radially (in the radial direction) relative to the drive axis A1. An elongated portion of the housing 10 extending in a direction substantially perpendicular to the drive axis A1 includes a grip portion 16 that is gripped by a user. The grip portion 16 is provided with a lever (also referred to as a trigger) 161 that is pressed by the user. When the lever 161 is pressed, the motor 20 is driven, causing the wedge 3 to reciprocate and the jaws 51 to move radially. The jaws 51 move radially outward, expanding the end of the pipe.

[0022] For convenience, in the following description, the extension direction of the drive shaft A1 is defined as the front-to-rear direction of the tube expansion tool 1. In the front-to-rear direction, the tip side of the wedge 3 is defined as the front side, and the opposite side is defined as the rear side. In addition, the direction perpendicular to the drive shaft A1 and corresponding to the longitudinal direction of the gripping portion 16 is defined as the up-to-down direction of the tube expansion tool 1. In the up-to-down direction, the protruding end side of the gripping portion 16 is defined as the bottom side, and the opposite side is defined as the top side. In addition, the direction perpendicular to the front-to-rear direction and the up-to-down direction is defined as the left-to-right direction of the tube expansion tool 1.

[0023] The detailed configuration of the tube expanding tool 1 will be described below.

[0024] As shown in FIG. 1, the housing 10 includes a portion (hereinafter referred to as the main body portion 11) extending in the front-to-rear direction along the drive axis A1, a grip portion 16 protruding downward from the rear end of the main body portion 11, and a controller accommodating portion 18 connected to the lower end of the grip portion 16.

[0025] A jaw assembly 5 is detachably connected to the front end of the main body 11. Inside the main body 11, there are mainly arranged a wedge 3, a reciprocating mechanism 4 for the wedge 3, and a rotating mechanism 6 for the jaw 51. The detailed configurations of the mechanisms (components) arranged inside the main body 11 and the jaw assembly 5 will be described later.

[0026] Inside the grip portion 16, a motor 20, a reducer 23, and a switch 163 are mainly arranged.

[0027] The motor 20 is disposed in the center of the grip part 16 in the vertical direction. In this embodiment, a brushless DC motor is used for the motor 20. An output shaft 201 of the motor 20 extends in the vertical direction and is rotatably supported at its upper and lower ends by bearings supported within the housing 10. The rotation axis of the output shaft 201 is perpendicular to the drive axis A1.

[0028] The reducer 23 is disposed above the motor 20 within the gripper 16 and is operably connected to an output shaft 201 of the motor 20. In this embodiment, a multi-stage planetary reducer is used for the reducer 23. The output shaft 201 of the motor 20 functions as an input shaft of the reducer 23. A drive shaft 41 is connected to the output shaft of the reducer 23. An axis A3 of the drive shaft 41 extends in the vertical direction and is perpendicular to the drive axis A1. In response to the driving of the motor 20, the drive shaft 41 is driven to rotate about the axis A3 at a slower rotational speed than the output shaft 201 of the motor 20. Note that instead of a planetary reducer, a reducer configured with a normal gear train may be used for the reducer 23.

[0029] The switch 163 is disposed within the lower end of the grip portion 16. The plunger 164 of the switch 163 is disposed directly behind the lever 161 disposed on the front side of the grip portion 16 (specifically, directly behind the rear end of the lever 161). The switch 163 is maintained in the OFF state while the lever 161 is not pressed. On the other hand, when the lever 161 is pressed rearward, the plunger 164 is pushed rearward by the lever 161, and the switch 163 is turned ON. The switch 163 is electrically connected to the controller 27 (described below) by an electric wire (not shown), and is configured to output a predetermined signal to the controller 27 while in the ON state.

[0030] A controller 27 that controls the operation of the tube expanding tool 1 is disposed within the controller housing 18. The controller 27 is configured, for example, by a microcomputer including a CPU, ROM, RAM, etc., or by another type of circuit. The controller 27 is configured to drive the motor 20 while the switch 163 is in the on state. In addition, a battery mounting section 181 is provided at the lower end of the controller housing 18. The battery mounting section 181 removably receives a rechargeable battery (also referred to as a battery pack or battery cartridge) 185. Although detailed illustrations and explanations are omitted, the battery mounting section 181 includes an engagement structure that can slidably engage with the battery 185 and terminals that can be electrically connected to the terminals of the battery 185.

[0031] The detailed configuration of the wedge 3 and the reciprocating mechanism 4 for the wedge 3 will be described below.

[0032] As shown in FIGS. 2 to 4, the wedge 3 is an elongated member having a conical (tapered) front portion (hereinafter referred to as the conical portion 31). More specifically, the front portion of the wedge 3 is configured so that the diameter decreases toward the front end. The wedge 3 may also be referred to as a needle, a cone, or the like. In this embodiment, the portion of the wedge 3 that extends rearward from the conical portion 31 is formed in a cylindrical shape (hereinafter referred to as the cylindrical portion 32). A flange portion 33 that protrudes radially outward beyond the outer circumferential surface of the cylindrical portion 32 is formed at the rear of the cylindrical portion 32.

[0033] The wedge 3 is disposed within the housing 10 (main body 11) so that its major axis coincides with the drive axis A1, and is held relative to the housing 10 so as to be able to linearly reciprocate in the front-to-rear direction along the drive axis A1. More specifically, a driven gear ring 68 constituted by a first ring 681 and a second ring 685 is disposed within the front end of the main body 11. As will be described in detail later, the driven gear ring 68 is part of the rotation mechanism 6 of the jaw 51. The driven gear ring 68 is supported by a bearing 111 so as to be rotatable about the drive axis A1 relative to the housing 10 but substantially immovable in the front-to-rear direction. The wedge 3 is inserted coaxially through the driven gear ring 68 and held so as to be able to slide relative to the driven gear ring 68 in the front-to-rear direction.

[0034] Furthermore, rotation of the wedge 3 around the drive shaft A1 is substantially prevented by the guide frame 113. The guide frame 113 is held substantially immovably relative to the housing 10 (main body 11) behind the driven gear ring 68. The front half of the guide frame 113 is a cylindrical member and is disposed around the wedge 3. The rear half of the guide frame 113 is composed of two protrusions 114 extending rearward from the upper and lower rear ends of the front half. A guide groove 115 is formed in each of the two protrusions 114. The two guide grooves 115 extend forward from the rear end of the guide frame 113, directly above and below the drive shaft A1, respectively.

[0035] Meanwhile, a pin 36 is engaged with the rear end of the wedge 3. More specifically, two protrusions 34 protrude rearward from the flange portion 33 of the wedge 3. The two protrusions 34 are arranged symmetrically with respect to the long axis of the wedge 3. A through hole is formed in each of the protrusions 34. The through hole penetrates the protrusion 34 in a direction perpendicular to the long axis of the wedge 3. The pin 36 is inserted into the through holes of the two protrusions 34 and engages with the wedge 3. Both ends of the pin 36 protrude radially outward from the protrusions 34 of the wedge 3 and are respectively arranged in two guide grooves 115 so as to be slidable in the front-rear direction. Thus, the pin 36 extends in the up-down direction and is movable in the front-rear direction relative to the housing 10 together with the wedge 3.

[0036] With this holding structure, the wedge 3 can move in the front-to-rear direction relative to the housing 10 (main body portion 11) within a range in which the pin 36 can slide along the guide groove 115, without substantially rotating around the drive axis A1. The wedge 3 is constantly biased rearward relative to the housing 10 and the jaw assembly 5 by the biasing spring 48. More specifically, the biasing spring 48 is a compression coil spring, and is disposed around (radially outward from) the wedge 3. One end of the biasing spring 48 abuts against the rear surface of the driven gear ring 68 from behind, and the other end of the biasing spring 48 abuts against the front surface of the flange portion 33 of the wedge 3 from the front.

[0037] Furthermore, a roller 37 is disposed around a portion of the pin 36 that is disposed between the two protruding portions 34 of the wedge 3 in the vertical direction. The roller 37 is rotatable around the axis of the pin 36 relative to the pin 36. A cam 45 of the reciprocating mechanism 4 is disposed directly behind the roller 37. Because the wedge 3 is biased rearward relative to the housing 10, the roller 37 is always in contact with the cam 45 (cam surface 450).

[0038] 2 to 4, the reciprocating mechanism 4 is operably coupled / engaged with the motor 20 and the wedge 3, and is configured to be driven by the motor 20 to reciprocate the wedge 3 along the drive axis A1. The reciprocating mechanism 4 of this embodiment includes a drive shaft 41, a cam 45, and the above-mentioned biasing spring 48.

[0039] The drive shaft 41 extends in the vertical direction, and is rotatably supported at its upper and lower ends by bearings 411, 412 supported within the housing 10 (main body 11). As described above, the drive shaft 41 is driven by the motor 20 to rotate around the axis A3 extending in the vertical direction.

[0040] The cam 45 is a member configured to convert rotational motion into linear motion. The cam 45 is fixed to the drive shaft 41 so as to rotate integrally with the drive shaft 41. More specifically, the cam 45 is fixed to a portion of the drive shaft 41 between the bearings 411 and 412 in the vertical direction. In this embodiment, the cam 45 is a plate cam (also known as a disc cam or a radial cam) whose distance from the rotation axis to its outer circumferential surface is not constant.

[0041] As described above, roller 37 operatively connected to wedge 3 is constantly pressed against the outer peripheral surface (cam surface 450) of cam 45 by the biasing force of biasing spring 48. Therefore, while motor 20 drives drive shaft 41 and cam 45 to rotate in one direction around axis A3 (the direction of arrow RD in FIG. 3), roller 37 rolls along cam surface 450, causing wedge 3 to reciprocate back and forth.

[0042] More specifically, while a portion of cam surface 450 of cam 45 where the distance from the rotation axis (axis A3) to cam surface 450 is minimum (hereinafter referred to as minimum diameter portion 451) is in contact with roller 37, wedge 3 is maintained at the rearmost position (hereinafter referred to as first position) within its movable range, as shown in FIGS. 2 and 3 . While a portion of cam surface 450 where the distance from axis A3 to the contact point between cam surface 450 and roller 37 increases with rotation (hereinafter referred to as diameter changing portion 452) is in contact with roller 37, wedge 3 moves forward from the first position. As shown in FIGS. 5 and 6 , when a portion of cam surface 450 where the distance from axis A3 to cam surface 450 is maximum (hereinafter referred to as maximum diameter portion 453) is in contact with roller 37, wedge 3 reaches the forwardmost position (hereinafter referred to as second position) within its movable range. When the roller 37 passes over the maximum diameter portion 453 in response to the rotation of the cam 45, the minimum diameter portion 451 faces the roller 37, and the wedge 3 moves rearward from the second position to the first position due to the biasing force of the biasing spring .

[0043] Thus, in this embodiment, one cycle of the reciprocating motion of the wedge 3 is defined by a waiting phase in which the wedge 3 is maintained at the first position, a movement phase from the first position to the second position (hereinafter also referred to as the forward phase), and a movement phase from the second position to the first position (hereinafter also referred to as the backward phase).

[0044] The detailed configuration of the jaw assembly 5 will be described below.

[0045] 2, 3, and 8, the jaw assembly 5 of this embodiment includes a plurality of jaws 51 and a cap 55. The jaw assembly 5 may also be referred to as an extension head, etc. The jaws 51 may also be referred to as a chuck, claws, etc., and the cap 55 may also be referred to as a collar, jaw holder, etc.

[0046] The multiple jaws 51 all have substantially the same shape and are arranged around the drive shaft A1. In this embodiment, there are six jaws 51. When viewed from the front, the shape of the front end (tip) of each jaw 51 is substantially a sector with a central angle of 60 degrees. A protrusion 511 that protrudes radially outward is provided at the rear end of each jaw 51. A groove 512 with an arc-shaped cross section is formed at the protruding end of the protrusion 511. In addition, a recess 515 that recesses forward from the rear end is formed at the rear end of each jaw 51.

[0047] The cap 55 is configured to hold the jaw 51 so that it can move radially relative to the drive shaft A1 and rotate around the drive shaft A1. More specifically, the cap 55 is a cylindrical member as a whole. The cap 55 is removably connected to the front end of the housing 10 (main body 11). In this embodiment, the cap 55 is threadedly engaged with the front end of the main body 11, but it may also be connected to the main body 11 by another method.

[0048] An annular recess 551 is formed inside the cap 55. The multiple jaws 51 are held by the cap 55 with each protrusion 511 positioned within the recess 551. The recess 551 has enough space inside to allow the protrusion 511 to move radially. An annular elastic member 553 is attached to the groove 512 of each protrusion 511 so as to surround all of the jaws 51. This constantly biases the multiple jaws 51 radially inward (toward the drive shaft A1 and wedge 3).

[0049] With this configuration, the multiple jaws 51 move radially as the wedge 3 reciprocates along the drive shaft A1. More specifically, as shown in Figures 2 and 3, when the wedge 3 is in the first position (rearmost position), the multiple jaws 51 are each positioned closest to the drive shaft A1 in the radial direction due to the biasing force of the elastic member 553. Hereinafter, the radial position of the multiple jaws 51 at this time will also be referred to as the closed position.

[0050] On the other hand, when the wedge 3 moves forward from the first position to the second position, the outer peripheral surface of the conical portion 31 of the wedge 3 abuts against the inner peripheral surfaces of the jaws 51 during the forward movement phase of the wedge 3, causing the jaws 51 to move radially outward. As shown in Figures 5 and 6, when the wedge 3 is located in the second position, the jaws 51 are each located at a position farthest from the drive shaft A1 in the radial direction. Hereinafter, the radial position of the jaws 51 at this time is also referred to as the open position.

[0051] Furthermore, when the wedge 3 moves rearward from the second position to the first position, the multiple jaws 51 are biased by the elastic member 553 to move radially inward as the wedge 3 retracts, and return to the closed position during the retraction phase of the wedge 3.

[0052] The detailed configuration of the rotation mechanism 6 of the jaw 51 will be described below.

[0053] As shown in Figures 2, 4 and 9, the rotation mechanism 6 of this embodiment includes a fixed shaft 63, a rotating shaft 60, a biasing spring 65, a one-way clutch 66, a driving gear ring 67, and a driven gear ring 68.

[0054] The fixed shaft 63 is supported in a substantially immovable manner relative to the housing 10 (main body 11). The fixed shaft 63 extends along an axis A2 parallel to the drive axis A1. More specifically, the rear end of the fixed shaft 63 is press-fitted into and fixed to a support hole in a support plate 630 that is fixedly supported on the main body 11, and the fixed shaft 63 extends in the front-to-rear direction directly below the wedge 3. Two cam grooves 631 are formed on the outer circumferential surface of the fixed shaft 63. The two cam grooves 631 are disposed symmetrically with respect to the long axis (axis A2) of the fixed shaft 63. The cam groove 631 extends obliquely (spiral-like) with respect to the axial and circumferential directions of the fixed shaft 63.

[0055] The rotating shaft 60 is disposed coaxially with the fixed shaft 63 and is supported rotatably about an axis A2 relative to the fixed shaft 63. In this embodiment, the rotating shaft 60 includes a first member 61 and a second member 62 that are operably and coaxially connected to each other.

[0056] The first member 61 includes a cylindrical portion 611 and a flange portion 615 formed at one axial end of the cylindrical portion 611. The first member 61 is fitted around the fixed shaft 63 with the flange portion 615 positioned rearward. A portion of the flange portion 615 is always located just forward of the lower end of the pin 36 (the portion extending downward from the lower protrusion 34 of the wedge 3). In other words, a portion of the flange portion 615 and the lower end of the pin 36 are on a straight line extending parallel to the axis A2 (i.e., in the front-to-rear direction). Two circular ball retaining holes 612 are formed in the cylindrical portion 611 symmetrically with respect to the axis of the first member 61. A ball 64 is rotatably fitted into and retained in each of the ball retaining holes 612. Each of the balls 64 is partially disposed in a cam groove 631 of the fixed shaft 63 and is capable of rolling within the cam groove 631.

[0057] With this configuration, the first member 61 is connected to the fixed shaft 63 via the ball 64. The first member 61 can rotate about the axis A2 while moving in the front-to-rear direction relative to the fixed shaft 63 and the housing 10 (main body 11) within a range in which the ball 64 can roll along the cam groove 631. In other words, the fixed shaft 63 and the first member 61 operably engaged with the fixed shaft 63 via the ball 64 constitute a motion conversion mechanism 600 that converts linear motion into rotational motion.

[0058] The second member 62 includes a cylindrical (cup-shaped) cylindrical portion 621 with a bottom, and a shaft portion 625 extending from the center of the bottom of the cylindrical portion 621. The second member 62 is supported rotatably relative to the housing 10 (main body 11) and substantially immovable in the front-to-rear direction, with the cylindrical portion 621 located on the rear side and the shaft portion 625 projecting forward. The second member 62 is coupled to the first member 61 so as to rotate integrally with the first member 61 relative to the fixed shaft 63, while allowing the first member 61 to move in the front-to-rear direction relative to the second member 62.

[0059] More specifically, a support plate 620 is fixedly held in front of a support plate 630 within the main body 11. The shaft 625 is inserted into a support hole formed in the support plate 620 and is rotatably supported by the support plate 620. A portion of the shaft 625 protrudes forward beyond the support plate 620. The inner diameter of the cylindrical portion 621 of the second member 62 is larger than the outer diameter of the cylindrical portion 611 of the first member 61, and a portion of the cylindrical portion 621 is disposed radially outward from the cylindrical portion 611. Two ball guide grooves 622 extending linearly in the axial direction are formed on the inner circumferential surface of the cylindrical portion 621, symmetrically with respect to the axis (axis A2) of the second member 62 (see FIG. 10 ). A portion of the ball 64 held in the ball holding hole 612 of the cylindrical portion 611 protrudes radially outward from the cylindrical portion 611 and engages with the ball guide groove 622.

[0060] With this configuration, the second member 62 is connected to the first member 61 via the ball 64. As the first member 61 rotates about the axis A2 while moving in the front-rear direction relative to the fixed shaft 63, the second member 62 rotates integrally with the first member 61 while allowing the first member 61 to move in the front-rear direction.

[0061] The biasing spring 65 is a compression coil spring and is disposed in a slightly compressed state (loaded state) between the support plate 620 and the first member 61 in the front-rear direction. More specifically, the front and rear ends of the biasing spring 65 abut against the rear surface of the support plate 620 and the front surface of the flange portion 615, respectively. The biasing spring 65 biases the first member 61 in a direction away from the support plate 620 (i.e., rearward relative to the fixed shaft 63 and the second member 62). Therefore, in an initial state in which no external force is applied forward, the first member 61 is held in a rearmost position (hereinafter also referred to as the initial position) in which the rear surface of the flange portion 615 abuts against the front surface of the support plate 630. Note that although the biasing spring 65 is preferably in a slightly compressed state in the initial state, it may also be disposed between the support plate 620 and the first member 61 in a substantially uncompressed state.

[0062] The coil diameter of the biasing spring 65 is slightly larger than the outer diameter of the cylindrical portion 621 of the second member 62, and the biasing spring 65 is disposed around (radially outward from) the cylindrical portion 621. Therefore, the cylindrical portion 611 of the first member 61, the cylindrical portion 621 of the second member 62, and a portion of the fixed shaft 63 are disposed inside (radially inward from) the biasing spring 65. With this configuration, the space occupied by the fixed shaft 63, the rotating shaft 60, and the biasing spring 65 can be made relatively small, and a relatively compact rotation mechanism 6 is realized.

[0063] The one-way clutch 66 is a clutch configured to transmit rotation in only one direction and rotate freely in the opposite direction. The one-way clutch 66 of this embodiment is a general-purpose one-way clutch and includes a cylindrical outer ring and a plurality of rolling elements (clutch members) arranged inside the outer ring. Rollers (specifically, needle rollers) are used as the rolling elements. However, any one-way clutch having a different configuration may be used. The one-way clutch 66 is arranged between the rotating shaft 60 and the drive gear ring 67 and is configured to transmit rotation of the rotating shaft 60 in only one predetermined direction to the drive gear ring 67.

[0064] The drive gear ring 67 is an annular (cylindrical) member having a gear, and includes a cylindrical portion 671 and gear teeth 675 protruding radially outward from the outer circumferential surface of the cylindrical portion 671. The outer ring of the one-way clutch 66 is press-fitted and fixed to the inner circumferential surface of the cylindrical portion 671 of the drive gear ring 67. In addition, a portion of the shaft portion 625 of the second member 62 that protrudes forward beyond the support plate 620 is inserted into the one-way clutch 66.

[0065] The driven gear ring 68 is an annular (cylindrical) member having gears, and as described above, is disposed around the wedge 3 coaxially with the wedge 3. The driven gear ring 68 is operably engaged with the drive gear ring 67 and the plurality of jaws 51, and is configured to be rotated by the drive gear ring 67 and to rotate integrally with the plurality of jaws 51. In this embodiment, the driven gear ring 68 includes a first ring 681 and a second ring 685 that are coaxially connected so as to be integrally rotatable.

[0066] The first ring 681 is a gear ring (annular (cylindrical) member having gears) and includes a cylindrical portion 682 and gear teeth 683 provided on the rear end portion of the cylindrical portion 682. The gear teeth 683 mesh with the gear teeth 675 of the drive gear ring 67.

[0067] The second ring 685 is a flanged annular (cylindrical) member and includes a cylindrical portion 686, a flange portion 687 provided at the front end of the cylindrical portion, and multiple protrusions 688 protruding forward from the front end of the cylindrical portion 686. The multiple protrusions 688 are arranged at equal intervals in the circumferential direction. In this embodiment, the number of protrusions 688 is six, corresponding to the number of jaws 51. Each protrusion 688 is configured to be engageable with a recess 515 at the rear end of a jaw 51. By engaging the protrusions 688 with the recesses 515 of the jaws 51, the second ring 685 and the multiple jaws 51 are connected to each other so as to be rotatable together.

[0068] The first ring 681 and the second ring 685 are connected to each other so as to rotate integrally as a driven gear ring 68 by engagement of teeth formed on the front end of the first ring 681 and the rear end of the second ring 685 (see FIG. 4). The driven gear ring 68 is rotatably supported around the drive axis A1 relative to the housing 10 (main body 11) by a common bearing 111 disposed between the gear teeth 683 of the first ring 681 and the flange portion 687 of the second ring 685. The bearing 111 is fixed to the inner circumferential surface of a retaining sleeve 112 that is fixedly supported inside the main body 11. The driven gear ring 68 is supported by the retaining sleeve 112 and the guide frame 113 so as to be substantially immovable in the front-to-rear direction relative to the housing 10 (main body 11).

[0069] In this embodiment, for ease of assembly, the driven gear ring 68 is formed of two separate members (the first ring 681 and the second ring 685) as described above. However, the driven gear ring 68 may be configured as a single (inseparable) member.

[0070] The rotation mechanism 6 configured as above rotates the plurality of jaws 51 in only one direction around the drive axis A1 by the elastic force (elastic energy, restoring force) of the biasing spring 65. The operation of the rotation mechanism 6 will be described below.

[0071] When a forward external force (pressing force) is applied to the first member 61 of the rotating shaft 60, the first member 61 rotates in a predetermined direction about the axis A2 while moving forward from the initial position relative to the fixed shaft 63, compressing (elastically deforming) the biasing spring 65. During this time, the second member 62 rotates in the predetermined direction together with the first member 61, without moving in the front-to-rear direction relative to the fixed shaft 63, while allowing the first member 61 to move forward. Hereinafter, the rotation direction of the rotating shaft 60 when the first member 61 moves forward relative to the fixed shaft 63 and the housing 10 will be referred to as the first direction. The first member 61 compresses (elastically deforms) the biasing spring 65 while moving forward from the initial position, thereby storing elastic force (elastic energy) in the biasing spring 65 (applying a load elastically).

[0072] When the rotary shaft 60 rotates in the first direction, the one-way clutch 66 rotates freely relative to the shaft portion 625 of the second member 62 and does not transmit rotation to the drive gear ring 67. In other words, even if the rotary shaft 60 rotates in the first direction, the drive gear ring 67 does not rotate. Therefore, the driven gear ring 68 and the plurality of jaws 51 do not rotate either.

[0073] On the other hand, after the first member 61 has moved forward from the initial position, when the external force (pressing force) acting forward on the first member 61 is released, the first member 61 is urged rearward by the elastic force (elastic energy, restoring force) accumulated in the urging spring 65. As a result, the first member 61 rotates around the axis A2 in a second direction opposite to the first direction while moving rearward. During this time, the second member 62 rotates together with the first member 61 in the second direction without moving in the front-to-rear direction relative to the fixed shaft 63, while allowing the first member 61 to move rearward. In this way, the elastic force accumulated in the urging spring 65 rotates the rotating shaft 60 in the second direction.

[0074] When the rotating shaft 60 rotates in the second direction, the one-way clutch 66 is locked to the shaft portion 625 of the second member 62 and rotates integrally with the rotating shaft 60, thereby transmitting the rotation to the drive gear ring 67. In other words, the drive gear ring 67 rotates integrally with the rotating shaft 60 in the second direction. Therefore, in response to the rotation of the drive gear ring 67, the driven gear ring 68 and the plurality of jaws 51 rotate around the drive axis A1 relative to the housing 10. In this way, the driven gear ring 68 and the plurality of jaws 51 rotate in one direction around the drive axis A1 only when the rotating shaft 60 is rotated in the second direction by the elastic force accumulated in the biasing spring 65.

[0075] Furthermore, in this embodiment, the rotation mechanism 6 is configured so that the forward and backward movement of the first member 61 partially corresponds to the forward and backward movement of the wedge 3. The correspondence between the operations of the reciprocating mechanism 4 and the wedge 3 and the operation of the rotation mechanism 6 will be described below.

[0076] Cam 45 rotates in response to the driving of motor 20, and while diameter changing portion 452 of cam surface 450 is in contact with roller 37, cam 45 moves wedge 3 from the first position (rearmost position) to the second position (forward most position) via roller 37 and pin 36. As described above, wedge 3 moves multiple jaws 51 from the closed position to the open position during part of this forward movement phase (see FIGS. 5 and 6).

[0077] Additionally, in response to a portion of the forward movement phase of the wedge 3, the lower end of the pin 36 abuts against the rear surface of the flange portion 615 of the first member 61, causing the first member 61 to move forward. Specifically, as shown in FIGS. 2 and 4 , when the wedge 3 is in the first position, the lower end of the pin 36 is located rearward and spaced apart from the first member 61, which is in the initial position. Hereinafter, the longitudinal position of the pin 36 at this time will be referred to as the "spaced position." In the forward movement phase, when the wedge 3 moves forward a predetermined distance from the first position, the lower end of the pin 36 abuts against the rear surface of the flange portion 615 from behind. Hereinafter, the longitudinal position of the pin 36 at this time will be referred to as the "contact position." Thereafter, as shown in FIGS. 5 and 7 , in response to the forward movement of the wedge 3 to the second position, the pin 36 moves forward from the abutment position, causing the first member 61 to move forward. As described above, during this time, the rotary shaft 60 rotates in the first direction, and the one-way clutch 66 does not operate, so the jaws 51 do not rotate.

[0078] As the motor 20 is driven, the cam 45 further rotates, and the roller 37 moves over the maximum diameter portion 453 of the cam surface 450, so that the minimum diameter portion 451 faces the roller 37, and the wedge 3 moves rearward from the second position to the first position. As described above, during part of this retraction phase of the wedge 3, the multiple jaws 51 move from the open position to the closed position (see FIGS. 2 and 3).

[0079] Furthermore, in response to a part of the retraction phase of the wedge 3, the first member 61 is moved rearward by the elastic force of the biasing spring 65. More specifically, at the same time that the minimum diameter portion 451 faces the roller 37, the forward pressing force applied to the first member 61 by the lower end of the pin 36 is released. Therefore, due to the elastic force accumulated in the biasing spring 65, the first member 61 rotates in the second direction while moving rearward, and the second member 62 also rotates in the second direction. Therefore, as described above, the one-way clutch 66 operates, and the jaw 51 is rotated via the drive gear ring 67 and the driven gear ring 68.

[0080] The angle by which the jaw 51 rotates while the first member 61 moves rearward along the cam groove 631 (the rotation angle of the jaw 51) is indirectly determined by the cam groove 631. More specifically, the rotation angle of the drive gear ring 67 is directly determined by the cam groove 631. On the other hand, since the drive gear ring 67 and the driven gear ring 68 constitute a speed reduction mechanism, the rotation angle of the driven gear ring 67 is directly determined by the cam groove 631. 68 The rotation angle of the jaw 51 is smaller than the rotation angle of the drive gear ring 67 in accordance with the gear ratio of this reduction mechanism.

[0081] Thus, in this embodiment, the force that rotates the rotary shaft 60, and therefore the driven gear ring 68 and the plurality of jaws 51, in the second direction is not a force applied by the cam 45 and the pin 36, but is the elastic force of the biasing spring 65. Furthermore, during the retraction phase of the wedge 3, the rearward movement of the wedge 3 is caused by the elastic force of the biasing spring 48, although it is synchronized with the rotation of the cam 45. The rotation of the driven gear ring 68 and the jaws 51 corresponds to a part of the retraction phase of the wedge 3, but is not caused in mechanical conjunction with the rearward movement of the wedge 3.

[0082] As described above, in the tube expanding tool 1 of this embodiment, the rotation mechanism 6 includes the driven gear ring 68, which rotates due to the elastic force (elastic energy, restoring force) of the biasing spring 65, and rotates the jaw 51 via the driven gear ring 68. Therefore, if the jaw 51 becomes unable to rotate for some reason, even if the driven gear ring 68 attempts to rotate the jaw 51, a force exceeding the elastic force of the biasing spring 65 is not applied to the driven gear ring 68 and other components of the rotation mechanism 6. This effectively reduces the possibility of damage to the rotation mechanism 6 due to excessive load. Furthermore, as a countermeasure for when the jaw 51 becomes unable to rotate for some reason, a mechanical clutch mechanism may be adopted. However, with a mechanical clutch mechanism, the torque at which transmission is interrupted must be precisely set. In this embodiment, a rotation mechanism 6 is realized that does not require such complicated settings.

[0083] In this embodiment, the rotation mechanism 6 rotates the jaws 51 in response to part of the retraction phase in which the wedge 3 moves from the second position to the first position. Therefore, the jaws 51 rotate while returning from the open position to the closed position after expanding the end of the pipe, i.e., while moving in a direction away from the inner circumferential surface of the expanded pipe. This makes it possible to reduce the influence of the inner circumferential surface of the pipe on the jaws 51, and the rotation mechanism 6 can smoothly rotate the multiple jaws 51.

[0084] In this embodiment, the rotation mechanism 6 accumulates elastic force in the biasing spring 65 in correspondence with a part of the forward movement phase in which the wedge 3 moves from the first position to the second position. Moreover, the rotation mechanism 6 rotates the plurality of jaws 51 by the elastic force accumulated in the biasing spring 65 in correspondence with a part of the backward movement phase in which the wedge 3 moves from the second position to the first position. Therefore, the phase in which the biasing spring 65 accumulates elastic force and the phase in which the jaws 51 are rotated using the elastic force accumulated in the biasing spring 65 can be reasonably matched to the movement phase of the wedge 3.

[0085] In this embodiment, the first member 61 moves in response to part of the forward movement phase of the wedge 3, elastically deforming the biasing spring 65, thereby efficiently accumulating elastic force in the biasing spring 65. In particular, the pin 36, which is driven linearly by the motor 20, is used to move the first member 61 forward. Because the pin 36 is also a member that moves the wedge 3 forward, a configuration that moves the first member 61 can be realized without increasing the number of parts.

[0086] In this embodiment, the rotating shaft 60 rotates in a first direction corresponding to a portion of the forward phase of the wedge 3, and rotates in a second direction corresponding to a portion of the backward phase of the wedge 3. Furthermore, a one-way clutch 66 interposed between the rotating shaft 60 and the drive gear ring 67 transmits only the rotation of the rotating shaft 60 in the second direction to the jaw 51, but does not transmit the rotation in the first direction. In this way, by employing the one-way clutch 66, a rational rotation mechanism 6 is realized that utilizes the rotating shaft 60 that can rotate in both directions (first direction and second direction) around the axis A2, and rotates the jaw 51 only while the rotating shaft 60 rotates in the second direction by the elastic force of the biasing spring 65 corresponding to a portion of the backward phase.

[0087] Furthermore, in this embodiment, the fixed shaft 63 of the rotation mechanism 6 and the rotating shaft 60 (more specifically, the first member 61) operably engaged with the fixed shaft 63 via the ball 64 constitute a motion conversion mechanism 600 that converts linear motion into rotational motion. The motion conversion mechanism 600 is actuated by the elastic force of the biasing spring 65 in response to at least a portion of the retreat phase of the wedge 3, and rotates the driven gear ring 68 and the jaw 51. In this way, by using the motion conversion mechanism 600, the jaw 51 can be efficiently rotated using the elastic force of the biasing spring 65. In particular, in this embodiment, the linear motion of the first member 61 is converted into rotational motion of the first member 61, thereby realizing a motion conversion mechanism 600 that is compact in the axial direction.

[0088] Furthermore, in this embodiment, the rotating shaft 60 includes a first member 61 and a second member 62 that are connected to each other and are rotatable together around the axis A2 and are movable relative to each other in the direction in which the axis A2 extends (the front-rear direction). With this configuration, the first member 61 and the second member 62 can be rotated together in the front-rear direction by moving only the first member 61 without moving the second member 62. Therefore, the second member 62 can rotate the driven gear ring 68 in a stable state via the drive gear ring 67.

[0089] Meanwhile, the first member 61 rotates by the elastic force of the biasing spring 65 in response to a portion of the retreat phase of the wedge 3, not only rotating the driven gear ring 68 and the jaw 51, but also moving back and forth in response to a portion of the advance phase of the wedge 3, thereby elastically deforming the biasing spring 65. In this way, by providing the first member 61 with multiple functions, a rational rotation mechanism 6 is realized that can accumulate elastic force in the biasing spring 65 and rotate the driven gear ring 68 and the jaw 51 with the accumulated elastic force.

[0090] The correspondence between each component (feature) of the above embodiment and each component (feature) of the present disclosure or invention is shown below. However, each component of the embodiment is merely an example and does not limit each component of the present disclosure or invention.

[0091] The tube expansion tool 1 is an example of a "tube expansion tool." The wedge 3 is an example of a "wedge." The drive shaft A1 is an example of a "first shaft." The first and second positions of the wedge 3 are examples of a "first position" and a "second position," respectively. The jaw 51 is an example of a "jaw." The closed and open positions of the jaw 51 are examples of a "closed position" and an "open position," respectively. The biasing spring 65 is an example of a "spring." The driven gearing 68 is an example of a "first rotating member." The forward movement phase of the wedge 3 is an example of a "phase of movement of the wedge from the first position to the second position." The backward movement phase of the wedge 3 is an example of a "phase of movement of the wedge from the second position to the first position."

[0092] The first member 61 is an example of a "movable member." The rotating shaft 60 is an example of a "second rotating member." Each of the first member 61 and the second member 62 is also an example of a "second rotating member." The one-way clutch 66 is an example of a "transmitting member." The motion conversion mechanism 600 is an example of a "motion conversion mechanism." The fixed shaft 63 is an example of a "fixed member." The ball 64 and the cam groove 631 are an example of a "cam portion." The first member 61 and the second member 62 of the rotating shaft 60 are examples of a "first part of the second rotating member" and a "second part of the second rotating member," respectively.

[0093] It should be noted that the above embodiment is merely an example, and the tube expansion tool according to the present disclosure is not limited to the illustrated tube expansion tool 1. For example, the following modifications can be made. Furthermore, at least one of these modifications can be adopted in combination with the tube expansion tool 1 illustrated in the embodiment and at least one of the features described in each claim.

[0094] For example, the wedge 3 does not necessarily have to be driven by the motor 20. Similarly, the power for elastically deforming the biasing spring 65 in the rotation mechanism 6 of the jaw 51 is not limited to the power of the motor 20. In other words, the tube expanding tool 1 does not need to be equipped with the motor 20, and may be equipped with a mechanism for moving the wedge 3 forward and a mechanism for moving the first member 61 forward in response to manual operation by the user. When a motor is employed, a motor other than a DC brushless motor (for example, a brushed motor or an AC motor) may be employed.

[0095] In the above embodiment, the pin 36 driven by the motor 20 has the function of moving the wedge 3 forward and the function of moving the first member 61 forward. However, the member that moves the wedge 3 forward and the member that abuts against the first member 61 and moves it forward may be different members. The shapes of these members and the connection / engagement / operation modes between the motor 20, the wedge 3, and the first member 61 may be changed as appropriate.

[0096] Furthermore, the correspondence relationship between the rearward movement of the wedge 3 and the rearward movement of the first member 61 due to the elastic force of the biasing spring 65 (the portion of the retreat phase of the wedge 3 to which the driven gear ring 68 and the jaw 51 rotate) may be changed as appropriate. For example, the first member 61 may rotate while moving rearward due to the elastic force of the biasing spring 65 in response to the middle, latter half, or entirety of the retreat phase of the wedge 3.

[0097] Furthermore, the reciprocating mechanism 4 for the wedge 3 may be any mechanism capable of linearly reciprocating the wedge 3, and may be, for example, a well-known crank mechanism including a crankshaft. Furthermore, instead of a plate cam, the cam 45 may be another type of flat cam (for example, a face grooved cam) or a three-dimensional cam (for example, a cylindrical grooved cam or a barrel cam).

[0098] The configuration of the jaw assembly 5 can be changed as appropriate. For example, the shape and number of the jaws 51 and the manner in which the jaws 51 are held by the cap 55 can be configured as desired. Note that, in order to enable replacement according to the type of pipe, it is preferable that the multiple jaws 51 are part of the jaw assembly 5 that is removable from the housing 10, as in this embodiment.

[0099] The rotation mechanism 6 may be modified in any way as long as it includes at least a spring and a rotating member that engages with the multiple jaws 51 so as to be rotatable integrally with the jaws 51 and rotates in only one direction around the drive axis A1 due to the elastic force of the spring.

[0100] For example, instead of biasing spring 65 (compression coil spring), other types of springs (for example, tension springs, torsion springs, disc springs, and power springs) may be used. Furthermore, the movable member that acts on the spring to elastically deform the spring and accumulate elastic force (elastic energy) is not limited to first member 61. For example, such a movable member may be a member that moves by being driven by a motor or in response to manual operation by a user, independent of motion conversion mechanism 600.

[0101] A motion converting mechanism having a different configuration may be employed instead of the motion converting mechanism 600 of the above embodiment. For example, instead of the ball 64 and the cam groove 631, a motion converting mechanism using a different type of cam portion (for example, an inclined surface inclined in the axial A2 direction and the circumferential direction) may be employed.

[0102] Furthermore, in the above embodiment, in order to rotate the driven gear ring 68 in only one direction, the rotating shaft 60 that rotates in both directions (first direction and second direction) about the axis A2 and the one-way clutch 66 are used. Alternatively, for example, the driven gear ring 68 may be rotated by a rotating member that does not rotate while the spring is elastically deformed in correspondence with at least a portion of the advance phase of the wedge 3, and that rotates by the elastic force of the spring in correspondence with only at least a portion of the retreat phase or standby phase of the wedge 3.

[0103] Furthermore, in consideration of the spirit of the present invention and the above-described embodiments, the following aspects are constructed. Any one or more of the following aspects may be adopted in combination with the tube expanding tool 1 of the embodiment and its modified examples, or the inventions described in the respective claims. [Aspect 1] The tube expansion tool is a housing defining the first axis; a motor housed in the housing, The wedge is configured to be reciprocally driven by the motor. According to this aspect, an efficient tube expanding tool utilizing a motor is realized. The housing 10 (main body 11) and the motor 20 are examples of the "housing" and "motor" of this aspect, respectively. [Aspect 2] The tube expansion tool further includes a cam operatively coupled to the motor and configured to be rotationally driven by the motor to reciprocate the wedge along the first axis. According to this aspect, with a simple configuration, it is possible to convert the rotational motion of the motor into linear motion and reciprocate the wedge. The cam 45 is an example of the "cam" of this aspect. [Aspect 3] The movable member is configured to be moved by the power of the motor. According to this aspect, the motor moves the wedge and the movable member, which is efficient. [Aspect 4] The expansion tool further includes an abutment member driven by the motor and configured to selectively abut against the movable member and move the movable member in response to at least a portion of the movement phase of the wedge from the first position to the second position. According to this aspect, the abutment member driven by the motor can be used to efficiently accumulate elastic force in the spring in response to at least a portion of the movement phase of the wedge from the first position to the second position. The pin 36 is an example of the "abutment member" in this aspect. [Aspect 5] The motion conversion mechanism is configured to be selectively actuated by the motor in correspondence with at least a portion of a movement phase of the wedge from the first position to the second position. According to this aspect, a configuration is realized in which, during the phase in which the wedge moves from the first position to the second position, linear motion is converted into rotational motion using the power of the motor, and during the phase in which the wedge moves from the second position to the first position, linear motion is converted into rotational motion using the elastic force of the spring. [Aspect 6] The movable member is part of the motion conversion mechanism and is configured to move linearly along the second axis while rotating around the second axis, thereby elastically deforming the spring. According to this aspect, the movable member exhibits the function of elastic deformation of the spring while operating as part of the motion conversion mechanism, so that an efficient mechanism can be realized without increasing the number of parts. [Aspect 7] The second rotating member also serves as the movable member. [Aspect 8] The tube expansion tool is a housing defining the first axis; a cap removably coupled to the housing and configured to hold the plurality of jaws movable between the closed position and the open position and rotatable about the first axis; The plurality of jaws and the cap form a jaw assembly. The cap 55 and the jaw assembly 5 are examples of the "cap" and "jaw assembly" of this embodiment, respectively. [Aspect 9] The jaws are biased toward the closed position by a resilient member, The wedge is configured to move in contact with the jaws during at least a portion of the movement phase from the first position to the second position, thereby moving the jaws from the closed position to the open position. [Aspect 10] the tube expansion tool further includes a third rotating member operably coupled to the transmission member and the first rotating member; The first rotating member and the third rotating member are gear rings that mesh with each other. The drive gear ring 67 is the "third rotating member" in this embodiment. [Aspect 11] The transmission member is a one-way clutch. According to this aspect, a simple and rational configuration can be realized that uses a one-way clutch that is a general-purpose component and that allows the first rotating member to rotate in only one direction. [Aspect 12] The cam portion is a cam groove formed in one of the fixed member and the second rotary member and extending obliquely or spirally around the second axis; a follower engaged with the cam groove and operatively connected to the other of the fixed member and the rotating member. The cam groove 631 and the ball 64 are examples of the "cam groove" and the "follower" of this embodiment, respectively. [Aspect 13] Of the first and second portions of the second rotating member, the first portion is operably engaged with the fixed member via the cam portion. [Aspect 14] The fixing member is a shaft extending along the second axis, The second rotating member is disposed at least partially around the fixed member. [Aspect 15] The first axis and the second axis extend parallel to and spaced apart from each other. [Explanation of symbols]

[0104] 1: tube expansion tool, 10: housing, 11: main body, 111: bearing, 112: retaining sleeve, 113: guide frame, 114: protrusion, 115: guide groove, 16: grip, 161: lever, 163: switch, 164: plunger, 18: controller accommodating section, 181: battery mounting section, 185: battery, 20: motor, 201: output shaft, 23: reducer, 27: controller, 3: wedge, 31: conical section, 32: cylindrical section, 33: flange section, 34: protrusion, 36: pin, 37: roller, 4: reciprocating mechanism, 41: drive shaft, 411: bearing, 412: bearing, 45: cam, 450: cam surface, 451: minimum diameter section, 452: diameter change section, 453: maximum diameter section, 48: biasing spring, 5: jaw assembly, 51: jaw, 5 11: protrusion, 512: groove, 515: recess, 55: cap, 551: recess, 553: elastic member, 6: rotation mechanism, 600: motion conversion mechanism, 60: rotation shaft, 61: first member, 611: cylindrical portion, 612: ball holding hole, 615: flange portion, 62: second member, 620: support plate, 621: cylindrical portion, 622: ball guide groove, 625: shaft portion, 63: fixed shaft 630: support plate, 631: cam groove, 64: ball, 65: biasing spring, 66: one-way clutch, 67: driving gear ring, 671: cylindrical portion, 675: gear teeth, 68: driven gear ring, 681: first ring, 682: cylindrical portion, 683: gear teeth, 685: second ring, 686: cylindrical portion, 687: flange portion, 688: protrusion, A1: driving shaft, A2: shaft, A3: shaft

Claims

1. 1. A tube expansion tool configured to expand an end of a pipe, comprising: a wedge reciprocatable along a first axis between a first position and a second position; a plurality of jaws movable relative to the first axis between a closed position and an open position radially outward of the closed position and rotatable about the first axis, the jaws configured to move from the closed position to the open position in response to movement of the wedge from the first position to the second position, and to move from the open position to the closed position in response to movement of the wedge from the second position to the first position; Springs and a first rotating member that engages with the plurality of jaws so as to be rotatable integrally with the plurality of jaws, the first rotating member being configured to rotate in only one direction around the first axis by the elastic force of the spring; the first rotating member is configured to rotate by the elastic force of the spring in response to at least a part of a movement phase of the wedge from the second position to the first position; a second rotating member configured to rotate in a first direction about a second axis corresponding to at least a portion of the movement phase of the wedge from the first position to the second position, and to rotate in a second direction opposite to the first direction about the second axis by the elastic force of the spring corresponding to at least a portion of the movement phase of the wedge from the second position to the first position; a transmission member operably connected to the first rotating member and the second rotating member and configured to transmit only rotation of the second rotating member in the second direction to the first rotating member.

2. The tube expansion tool according to claim 1, the spring is configured to accumulate the elastic force corresponding to at least a part of a movement phase of the wedge from the first position to the second position; A tube expansion tool characterized in that the first rotating member is configured to rotate by the elastic force accumulated in the spring corresponding to at least a portion of the movement phase of the wedge from the second position to the first position.

3. The tube expanding tool according to claim 2, A tube expansion tool further comprising a movable member operably connected to the spring and configured to move in correspondence with at least a portion of the movement phase of the wedge from the first position to the second position and to elastically deform the spring.

4. The tube expanding tool according to any one of claims 1 to 3, a motion conversion mechanism operably coupled to the spring and the first rotary member and configured to convert linear motion into rotary motion; The motion conversion mechanism is configured to operate by the elastic force of the spring in response to at least a portion of the movement phase of the wedge from the second position to the first position, thereby rotating the first rotating member.

5. The tube expanding tool according to claim 4, The motion conversion mechanism includes: A fixing member; a second rotating member operably engaged with the fixed member via a cam portion; A tube expansion tool characterized in that at least a portion of the second rotating member is configured to rotate the first rotating member by moving along the second axis relative to the fixed member while rotating around the second axis.

6. The tube expanding tool according to claim 5, The spring is a coil spring, The tube expanding tool, wherein the fixed member and the second rotating member are at least partially housed inside the coil spring.

7. The tube expanding tool according to claim 5 or 6, A tube expansion tool characterized in that the second rotating member includes a first part and a second part that are connected to each other and can rotate together around the second axis and can move relatively along the second axis.

8. The tube expansion tool according to claim 7, A tube expansion tool characterized in that the first part is movable along the second axis relative to the fixed member and the second part, and is configured to elastically deform the spring by moving along the second axis corresponding to at least a portion of the movement phase of the wedge from the first position to the second position.

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