Pipe expanding tool

Abstract

A pipe expanding tool (1) expands the diameter of the end of a synthetic resin fluid pipe. A pipe expanding tool (1) is provided with a motor shaft (20a) that is rotated by a motor (20). The feed screw mechanism (25) converts rotation of the motor shaft (20a) into forward and backward movement of the output shaft (27). A wedge (3) provided on the front portion of the output shaft (27) presses the plurality of claws (4). The plurality of claws (4) are expanded to the outside in the radial direction. A claw rotation mechanism (30) having a shaft (31) is provided. The shaft (31) rotates about the axis in conjunction with the rotation of the motor shaft (20a). The shaft (31) rotates the plurality of claws (4) about the axis. The output shaft (27), the motor shaft (20a), and the shaft (31) of the claw rotation mechanism (30) are arranged side by side and overlap each other in the front-rear direction.

Description

Technical Field

[0001] One aspect of the present invention relates to a tube diameter expanding tool for expanding the diameter of an end portion of a fluid tube made of, for example, synthetic resin in order to connect the end portion to a connected body. Background Art

[0002] For example, a fluid pipe (hereinafter referred to as a PEX pipe) made of PEX (Cross-linked polyethylene) is sometimes connected to a connected body such as a resin pipe fitting. The prior art provides a pipe expansion tool for expanding the inner diameter of the end of the PEX pipe. After the end of the PEX pipe is expanded using the pipe expansion tool, it is installed on the connected body. The end of the PEX pipe is reduced in diameter by elastic deformation in a manner that gradually returns to the original diameter. Accordingly, the end of the PEX pipe is tightly connected to the connected body. The PEX pipe is firmly held to the connected body by its own elasticity.

[0003] The specification of U.S. Patent No. 9862137 describes a pipe expansion tool that uses an electric motor as a driving source to expand the diameter of a PEX pipe. The pipe expansion tool is provided with a wedge having a substantially conical front end and a plurality of jaws arranged in the circumferential direction of the wedge in front of the wedge. The wedge is mounted on the front end of an output shaft that moves back and forth inside the pipe expansion tool. When the wedge moves forward together with the output shaft, the plurality of jaws are pressed by the wedge and open to each other radially outward of the wedge. By opening the plurality of jaws radially outward while entering the end opening of the PEX pipe, the end of the PEX pipe can be expanded.

[0004] For example, when the pipe expansion tool has six claws, the end of the PEX pipe is subjected to the force of opening radially outward by each claw at six locations at equal intervals in the circumferential direction. Therefore, in one expansion action, the end of the PEX pipe is expanded into a roughly hexagonal shape. In order to expand the end of the PEX pipe into a circular shape, the expansion action and the rotation action are repeated alternately, wherein the rotation action refers to the action of rotating multiple claws at a specified angle (for example, 15° to 30°) in the circumferential direction of the wedge. Accordingly, the position where each claw contacts the inner circumferential surface of the PEX pipe is moved by the rotation action. Therefore, the end of the PEX pipe is uniformly expanded and close to a circle.

[0005] For example, a PEX pipe may be placed between two walls facing each other with a narrow gap (see Figure 2). In order to improve the workability of expanding the end of a PEX pipe installed in a narrow place, it is preferred that the pipe expanding tool is compact in the front-to-back direction. The pipe expanding tool has a power conversion mechanism that converts the rotational drive of the motor into the front-to-back movement of the output shaft, and a claw rotation mechanism that rotates the claw. As described in the specification of U.S. Patent No. 9,862,137, in the pipe expanding tool of the prior art, the claw rotation mechanism is coaxially arranged with the output shaft. Therefore, it is difficult to compactly arrange the pipe expanding tool in the front-to-back direction.

[0006] A pipe expansion tool is also disclosed in the specification of U.S. Patent No. 2020 / 0261959, which expands the diameter of the PEX pipe by a feed screw mechanism driven by an electric motor. At the front of the pipe expansion tool, a roughly conical wedge is provided, which advances or retreats relative to the end of the PEX pipe by the feed screw mechanism. In front of the wedge, a plurality of claws are arranged in the circumferential direction of the wedge. The plurality of claws are pressed by the advancing wedge and open to each other radially outward of the wedge. The plurality of claws are opened radially outward in a state where the plurality of claws enter the end opening of the PEX pipe, thereby expanding the end of the PEX pipe. Usually, in the expansion operation of the PEX pipe, the diameter is expanded to a specified size by repeating the opening action of the claws multiple times. For example, for a PEX pipe with a diameter of 1 inch, the opening action of the claws required to expand the PEX pipe to a specified size is usually 12 to 18 times.

[0007] In the conventional pipe expansion tool, the jaws are opened only once by a single start operation (trigger on operation) by the user. Therefore, the user needs to repeat the start operation of the pipe expansion tool the required number of times of jaw opening, which places a heavy burden on the user. Summary of the invention Technical problem to be solved by the invention

[0008] Therefore, there is a need in the prior art for a pipe diameter expanding tool that is compactly arranged in the front-rear direction. Alternatively, there is a need in the prior art for a pipe diameter expanding tool that can reduce the burden on the user when performing the diameter expanding operation on a PEX pipe. Technical solutions for solving technical problems

[0009] One feature of the present invention relates to a tube expansion tool for expanding the diameter of the end of a fluid tube made of synthetic resin. The tube expansion tool has a motor shaft that is rotated by an electric motor. A power conversion mechanism converts the rotation of the motor shaft into forward and backward movement of an output shaft. A wedge arranged at the front of the output shaft presses a plurality of claws. The plurality of claws are opened radially outward from each other. A claw rotation mechanism having an axis is provided. The shaft rotates around an axis in conjunction with the rotation of the motor shaft. The shaft rotates the plurality of claws around an axis. The output shaft, the motor shaft, and the axis of the claw rotation mechanism are arranged in parallel and overlapped in the front-to-back direction.

[0010] Therefore, the tube expansion tool can be compactly arranged in the front-rear direction. In addition, the output shaft, the motor shaft and the shaft are arranged in parallel with each other. Therefore, the tube expansion tool can be compactly arranged even in the direction intersecting the front-rear direction (up-down direction or left-right direction). BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a perspective view of a pipe expanding tool according to an embodiment of the present invention. Figure 2 This is a perspective view of a pipe expanding tool for expanding the diameter of an end portion of a PEX pipe. Figure 3 This is a perspective view of the tool body with the main body casing removed, as viewed from the right front. Figure 4 This is a three-dimensional exploded view of the tool body. Figure 5 This is a perspective view of the tool body with the main body case removed, as seen from the right rear. Figure 6 This is a perspective view of the tool body with the body casing removed, as viewed from the left front. Figure 7 This is a perspective view of the tool body from which the body case is removed, as viewed from the left rear, and is a perspective view showing a state in which the output shaft is located at the rear end position. Figure 8 This is a perspective view of the tool body with the body case removed, as viewed from the left rear, and is a perspective view showing a state in which the output shaft is located at the front end position. Fig. 9 This is a rear view of a state in which the main body casing of the tool main body is removed. Fig.10 is an exploded perspective view of the components including the rear axle. Fig.11 is a perspective view showing an assembly including a tool body and a rear axle. Fig.12 yes Fig. 9 Section view XII-XII in. Fig.13 yes Fig.12 Section view XIII-XIII in FIG. Fig.14 When the output shaft is at the rear end Fig.13 Section view XIV-XIV. Fig.15 When the output shaft is at the front end Fig.13 Section view XIV-XIV. Fig.16 When the output shaft is at the rear end Fig.13 Section view XVI-XVI. Fig.17 When the output shaft is at the front end Fig.13 Section view XVI-XVI. Fig.18 is the block diagram of the controller. Fig.19 It is a diagram that represents the control flow. Fig. 20 It is a diagram that represents the control flow. DETAILED DESCRIPTION

[0012] According to another feature of the present invention, the shaft of the claw rotating mechanism and the motor are arranged so that more than 80% of their respective axial lengths overlap with the output shaft at the rear end in the front-to-back direction. Therefore, the protrusion of the shaft of the claw rotating mechanism and the motor relative to the output shaft in the front-to-back direction is suppressed. In particular, the protrusion of the output shaft at the rear end toward the rear is suppressed. Accordingly, the compactness of the tube expansion tool in the front-to-back direction can be improved.

[0013] According to another feature of the present invention, the shaft of the claw rotating mechanism and the motor are arranged in such a manner that their respective axial lengths overlap with the output shaft at the rear end in the front-to-back direction. Therefore, the shaft of the claw rotating mechanism and the motor do not protrude in the front-to-back direction relative to the output shaft at the rear end. Accordingly, the compactness of the tube expanding tool in the front-to-back direction can be further improved.

[0014] According to another feature of the present invention, the tube expansion tool has a speed change mechanism for changing the speed of the rotation output of the motor shaft. An idler wheel is provided between the speed change mechanism and the power conversion mechanism. Therefore, the speed change mechanism can be arranged to overlap with the power conversion mechanism in the axial direction (front-rear direction). Therefore, the electric motor arranged near the speed change mechanism can be arranged close to the power conversion mechanism. Accordingly, the tube expansion tool can be compactly arranged in the front-rear direction.

[0015] According to another feature of the present invention, the output shaft and the motor shaft are offset in the up-down direction orthogonal to the front-back direction. The claw rotating mechanism is located between the output shaft and the motor shaft in the up-down direction when viewed in the axial direction of the output shaft. Therefore, in addition to the up-down direction orthogonal to the front-back direction, the output shaft, the claw rotating mechanism and the motor can also be compactly arranged in the up-down direction orthogonal to the front-back direction. Therefore, it is possible to suppress the tube expansion tool from becoming longer in the up-down direction.

[0016] According to another feature of the present invention, the claw rotating mechanism is offset relative to the imaginary plane including both the motor shaft and the output shaft. Therefore, in the extension direction (up and down direction) of the imaginary plane in which the motor shaft and the output shaft are arranged, the output shaft, the claw rotating mechanism and the motor can be compactly arranged. Accordingly, the pipe expansion tool can be compactly arranged in the up and down direction.

[0017] According to another feature of the present invention, the claw rotating mechanism has a one-way clutch. The one-way clutch rotates in conjunction with the first rotation of the shaft to rotate the plurality of claws. On the other hand, the one-way clutch does not rotate in conjunction with the second rotation of the shaft that is opposite to the first rotation. The shaft of the claw rotating mechanism has a rear shaft and a front shaft that is screwed with the front portion of the rear shaft. Therefore, the shaft of the claw rotating mechanism can be separated into a rear shaft and a front shaft, and the rear shaft is assembled to a component for rotating the shaft; the front shaft is assembled to a tool body in order to transmit the rotational drive of the shaft to a plurality of claws. The tool body on the front shaft side and the component on the rear shaft side are separately assembled, and after assembly, the front shaft and the rear shaft are connected in the front-to-back direction by screwing. Accordingly, the assemblability of the shaft can be improved.

[0018] According to another feature of the present invention, the front axle is screwed with respect to the rear axle to be fastened to the rear axle in the direction of the first rotation. Therefore, when the front axle performs the first rotation, the torque is transmitted from the front axle to the multiple claws through the one-way clutch, and the torque acts in the direction in which the rear axle is fastened relative to the front axle. Therefore, the fastening force between the rear axle and the front axle becomes stronger. On the other hand, when the front axle performs the second rotation, the torque transmitted from the front axle to the multiple claws is a tiny amount. Therefore, the front axle is almost free to rotate without resistance and performs the second rotation. The rear axle rotates in the direction of loosening relative to the front axle, but no resistance is applied to the front axle. Therefore, the fastening force with the front axle will not loosen and rotate. In this way, it is possible to suppress the screwing of the front axle and the rear axle from loosening due to the action of the claw rotating mechanism.

[0019] According to another feature of the present invention, the power conversion mechanism is a feed screw mechanism, and the feed screw mechanism has an external thread arranged on the outer periphery of the output shaft, and a nut penetrated by the external thread. Therefore, the power conversion mechanism can be arranged around the output shaft. Therefore, it is possible to suppress the power conversion mechanism from protruding in the axial direction (front-to-back direction) relative to the output shaft. Accordingly, the pipe expansion tool can be compactly arranged in the front-to-back direction.

[0020] According to another feature of the present invention, the tube expansion tool has a handle extending in a direction intersecting the axial direction of the output shaft. At least a portion of the nut of the feed screw mechanism and at least a portion of the motor overlap with the handle in the front-to-back direction. Therefore, the nut of the feed screw mechanism and the motor can be arranged near the support center when the user holds the handle to support the tube expansion tool. Accordingly, the weight balance of the tube expansion tool in the front-to-back direction can be improved.

[0021] According to another feature of the present invention, for example, the end of a fluid tube made of synthetic resin is expanded by a tube expansion tool. The tube expansion tool has an internal thread component. The internal thread component rotates forward by the forward rotation of the motor and reverses by the reverse rotation of the motor. The screw shaft is screwed with the internal thread component. The screw shaft advances from an initial position to a terminal position by the forward rotation of the internal thread component. The screw shaft retreats from the terminal position to an initial position by the reverse rotation of the internal thread component. A wedge extends forward from the screw shaft. When the wedge advances together with the screw shaft, the wedge presses a plurality of claws. The plurality of claws open to each other radially outward. An operating component for starting the motor is provided. The controller causes the motor to repeatedly rotate forward and reverse during the operation of the operating component, thereby opening the plurality of claws multiple times.

[0022] Therefore, the claws are opened multiple times during one operation of the operating member, thereby reducing the burden on the user.

[0023] According to another feature of the present invention, at least one of the initial position and the terminal position of the screw shaft is detected by the detection device. Therefore, the reciprocating motion of the screw shaft is performed quickly and reliably.

[0024] According to another feature of the present invention, both the initial position and the terminal position of the screw shaft are detected by the detection device, so that the reciprocating motion of the screw shaft can be performed more quickly and reliably.

[0025] According to another feature of the present invention, the controller reverses the motor after the operation of the operating member is released to return the screw shaft to the initial position. Therefore, when the operation of the operating member is released, the screw shaft retreats and returns to the initial position, whereby the claw reliably returns to the closed position.

[0026] According to another feature of the present invention, when the screw shaft is not in the initial position when the operation of the operating member starts, the controller reverses the motor when the operation of the operating member starts so that the screw shaft returns to the initial position. Therefore, it is prevented that the screw shaft starts to move forward from the midway position. Accordingly, the opening action of the claw does not start from the half-open state, but always starts from the closed position.

[0027] According to another feature of the present invention, during the operation of the operating member, the controller measures the number of reciprocating movements of the screw shaft between the initial position and the terminal position. The controller stops the rotation of the motor when the number of reciprocating movements reaches a preset number. Therefore, even during the operation of the operating member, the motor automatically stops at the time point when the opening action of the claws is performed for a preset number of times. Accordingly, an appropriate diameter expansion action is quickly performed.

[0028] According to another feature of the present invention, the controller calculates the number of reciprocating movements according to the rotation speed of the motor. Therefore, when the rotation speed of the motor reaches the set number, the motor automatically stops after the screw shaft returns to the initial position. Accordingly, the burden on the user is reduced for multiple diameter expansion actions of the claw.

[0029] According to another feature of the present invention, the detection device is a Hall IC sensor. Therefore, one or both of the initial position and the terminal position of the screw shaft are detected by the Hall IC sensor.

[0030] According to another feature of the present invention, the detection device is a detection circuit that detects the position of the screw shaft based on the rotation speed of the motor. Therefore, one or both of the initial position and the terminal position of the screw shaft are detected by the detection circuit.

[0031] According to another feature of the present invention, the tube expansion tool has a ball screw, and the ball screw is provided with balls between the screw shaft and the internal threaded component. Therefore, the screw shaft is smoothly and smoothly screwed with the internal threaded component. Accordingly, the screw shaft reciprocates accurately and smoothly.

[0032] Next, according to Figures 1 to 20 An embodiment of the present invention is described below. Figure 1 As shown, the pipe expansion tool 1 of this embodiment has a tool body 10 housed in a main body housing 11 and a handle 5 extending downward from the lower portion of the main body housing 11. The user is located approximately behind the pipe expansion tool 1 ( Figure 1 In the following description, the side close to the user is defined as the rear side, and the side opposite to the side close to the user is defined as the front side. The up, down, left, and right directions are based on the user.

[0033] like Figure 1 , Figure 4 , Fig.12As shown, an annular end cap 2 is installed at the front of the tool body 10. A cylindrical output shaft 27 extending in the front-to-back direction is provided in the center of the tool body 10. A roughly conical wedge 3 is installed at the front end of the output shaft 27. The wedge 3 is located radially inside the end cap 2. The output shaft 27 and the wedge 3 are arranged on the output axis K extending in the front-to-back direction at the approximate center of the upper and lower and left and right sides of the tool body 10. The output shaft 27 and the wedge 3 can move in the front-to-back direction between the initial position (rear end position) at the rear and the terminal position (front end position) at the front along the output axis K. A plurality of claws 4 extending in the front-to-back direction are provided radially outside the wedge 3 and radially inside the end cap 2. The plurality of claws 4 are arranged at equal intervals in the circumferential direction of the wedge 3. The pipe expansion tool 1 has, for example, 6 claws 4, and each claw 4 is arranged at 60° intervals in the circumferential direction of the wedge 3. The plurality of claws 4 can be opened and closed in the radial direction between a closed position and an open position, wherein the closed position is a position in which the claws 4 are in close contact with each other in the circumferential direction and cover the wedge 3 , and the open position is a position in which the claws 4 are opened radially outward and the top end of the wedge 3 is exposed.

[0034] like Figure 1 , Fig.12 As shown, a trigger-type operating component (e.g., a switch operating lever) 6 is provided on the front surface of the handle 5. The user can pull the operating component 6 while holding the handle 5. Inside the handle 5, a switch body 6a is provided that switches on / off in conjunction with the operation of the operating component 6. When the operating component 6 is not pulled, the switch body 6a is in an off state, and when the operating component 6 is pulled, the switch body 6a becomes an on state. At the lower end of the handle 5, a roughly rectangular box-shaped enlarged diameter portion 7 that is enlarged in the front-to-back direction and the left-to-right direction is provided. A controller 9 is accommodated in the enlarged diameter portion 7. The controller 9 has a shallow-bottomed rectangular box-shaped housing, and a control substrate that is housed in the housing and is resin-molded. The controller 9 is housed in the enlarged diameter portion 7 in a posture along the up-down direction in the thickness direction (the direction in which the shortest side of the housing extends). The controller 9 mainly controls the drive of the motor 20 described later.

[0035] like Figure 1As shown, an operation panel 7b is provided on the upper surface of the enlarged diameter portion 7. Various operation buttons are provided on the operation panel 7b, for example, for presetting the number of opening and closing actions of the claw 4. When the operation button 7c is long pressed, the operation panel 7b is activated. The activation state is notified by the display portion 7d lighting up. By pressing the operation button 7e in the activation state, the tens digit as the set number can be set. The tens digit is numerically displayed on the display portion 7f. Similarly, by pressing the operation button 7g in the activation state, the ones digit as the set number can be set. The ones digit is numerically displayed on the display portion 7h. The user can pre-set the number of opening and closing actions of the claw 4 by pressing the operation buttons 7e and 7g. During one detent operation of the operating member 6, the opening and closing action of the claw 4 is continuously performed for a set number of times. When the claw 4 is opened and closed continuously for a set number of times, the motor 20 stops automatically.

[0036] like Figure 1 As shown, a battery mounting portion 7a is provided on the lower surface of the enlarged diameter portion 7 to which a rectangular box-shaped battery 8 can be detachably mounted. The battery 8 can be removed from the battery mounting portion 7a by sliding forward. The battery 8 can be mounted on the battery mounting portion 7a by sliding from the front to the rear of the battery mounting portion 7a. The battery 8 can be removed from the battery mounting portion 7a and repeatedly charged with a charger prepared separately for use. The battery 8 can be used as a power source for other electric tools. The battery 8 operates as a power source for supplying electric power to the motor 20.

[0037] like Figure 2 As shown in the figure, when using the tube expansion tool 1, the user holds the handle 5 and inserts the plurality of claws 4 into the end 51a of the PEX tube (fluid tube) 51 made of synthetic resin. By depressing the operating member 6, the plurality of claws 4 are opened and closed in the radial direction. As a result, the end 51a of the PEX tube 51 is expanded. The PEX tube 51 is, for example, arranged between two walls 52 facing each other. Therefore, it is preferable that the front-to-rear length of the tube expansion tool 1 is accommodated in the narrow space between the two walls 52.

[0038] like Figure 4 As shown, in the tool body 10, the front mechanism housing 12, the first central mechanism housing 13, the second central mechanism housing 14 and the rear mechanism housing 15 are housed in sequence from the front side to the rear side. The front mechanism housing 12, the first central mechanism housing 13 and the second central mechanism housing 14 are substantially cylindrical in shape with a hollow path passing through the center in the front-to-back direction. The rear mechanism housing 15 is set in a plate shape with the front-to-back direction as the plate thickness direction. The front mechanism housing 12, the first central mechanism housing 13, the second central mechanism housing 14 and the rear mechanism housing 15 cooperate to form a mechanism housing. The gear shaft 23, the idler gear 24 and the nut 26 described later are housed in the mechanism housing.

[0039] like Figure 3, Figure 4 As shown, an external thread 12a is provided on the front outer peripheral surface of the front mechanism housing 12. An internal thread 2b screwed with the external thread 12a is provided on the rear inner peripheral surface of the end cover 2. By screwing the external thread 12a and the internal thread 2b together, the end cover 2 is connected to the front part of the front mechanism housing 12.

[0040] like Figure 3 , Figure 4 As shown, on the outer peripheral surface of the front mechanism housing 12, four bosses 12c of a substantially cylindrical shape extending radially outward are provided. In the bosses 12c, threaded holes 12d penetrating in the front-to-back direction are formed. The first central mechanism housing 13 and the second central mechanism housing 14 respectively have four bosses 13g and 14j of a substantially cylindrical shape extending radially outward. In each of the bosses 13g and 14j, through holes 13h and 14k penetrating in the front-to-back direction are provided. In the four corners of the rear mechanism housing 15, through holes 15b penetrating in the front-to-back direction are provided. By arranging the bosses 12c, 13g, 14j and the through holes 15b in the front-to-back direction, the threaded holes 12d and the through holes 13h, 14k, and 15b are connected in the front-to-back direction. Four bolts 16 are inserted from the rear to the front into the connected through holes 15b, 14k, and 13h and fastened to the threaded holes 12d. As a result, the front mechanism case 12 , the first center mechanism case 13 , the second center mechanism case 14 , and the rear mechanism case 15 are connected in parallel in the front-rear direction.

[0041] like Figure 3 , Figure 4 As shown, the first central mechanism housing 13 has a cylindrical downwardly extending portion 13b with a generally U-shaped outer shape. The second central mechanism housing 14 has a cylindrical downwardly extending portion 14b with a generally U-shaped outer shape. The downwardly extending portion 13b and the downwardly extending portion 14b are connected in the front-to-back direction to form a space for accommodating the gear shaft 23 and the idler gear 24. The downwardly extending portion 13b has two through holes extending in the front-to-back direction arranged side by side in the upper and lower directions. The through hole on the lower side is provided with a recessed portion 13c for supporting the gear shaft 23 described later. The shaft member 24a supporting the idler gear 24 is pressed into the through hole 13d on the upper side. The downwardly extending portion 14b has two through holes extending in the front-to-back direction arranged side by side in the upper and lower directions. The through hole on the lower side is provided with a recessed portion 14c for supporting the gear shaft 23. The shaft member 24a is inserted into the through hole 14d on the upper side.

[0042] like Figure 3 , Fig.12As shown, a roughly cylindrical electric motor 20 is housed in the rear lower portion of the main body housing 11. The electric motor 20 uses, for example, a motor called a brushless DC motor. The electric motor 20 is located below the output shaft 27 at the rear end position and above the handle 5. More than 80% of the axial (front-to-back direction) length of the electric motor 20 overlaps with the output shaft 27 at the rear end position. In the present embodiment, the entire axial length of the electric motor 20 overlaps with the output shaft 27 at the rear end position. The motor shaft 20a of the electric motor 20 extends in the front-to-back direction along the motor axis J and parallel to the output axis K passing through the center of the output shaft 27. The motor axis J is vertically parallel to the output axis K on an imaginary plane S extending in the up-down direction (refer to FIG. 2 ). Fig.13 The motor shaft 20a is supported by bearings 20e and 20f so as to be rotatable about the motor axis J. The bearing 20e is provided between the motor 20 and a planetary reduction mechanism 22 described later. The bearing 20f is supported by the inner wall of the rear surface of the main body housing 11.

[0043] like Fig.12 As shown, the motor 20 has a stator 20b supported in a manner that is non-rotatable relative to the main body housing 11. The stator 20b is arranged on the radially outer side of the motor shaft 20a. The rotor 20c of the motor 20 is mounted on the motor shaft 20a on the inner circumferential side of the stator 20b in a manner that is rotatable together with the motor shaft 20a. A rotation speed detection sensor 20d is provided in front of the rotor 20c. The rotation speed detection sensor 20d detects the rotation speed of the motor shaft 20a by detecting the rotation angle of the rotor 20c. In the front-to-back direction, between the rotor 20c and the rear bearing 20f, a fan 21 for introducing cooling air into the motor 20 is integrally installed with the motor shaft 20a. When the fan 21 rotates together with the motor shaft 20a, the cooling air flows from the front to the rear of the motor 20.

[0044] like Fig.12 As shown, a planetary reduction mechanism (speed change mechanism) 22 for reducing the output of the motor shaft 20a is provided in front of the motor 20. The planetary reduction mechanism 22 is a roughly cylindrical shape with the motor axis J as the center and a diameter substantially the same as that of the motor 20. The planetary reduction mechanism 22 is arranged in the front-to-back direction with the motor 20 and is accommodated in the main body housing 11. The first sun gear 22a of the planetary reduction mechanism 22 is integrally provided with the front end of the motor shaft 20a in front of the bearing 20e. A ring-shaped first internal gear 22b centered on the motor axis J is provided on the radially outer side of the first sun gear 22a. A plurality of first planetary gears 22c are meshed between the first sun gear 22a and the first internal gear 22b. The first planetary gear 22c is connected to the first planetary carrier 22d in front of the first sun gear 22a. The rotational drive of the motor shaft 20a is reduced and transmitted to the first planetary carrier 22d through the first sun gear 22a and the first planetary gear 22c.

[0045] like Fig.12 As shown, the first planetary carrier 22d is integrally provided with the second sun gear 22e in front, and can rotate with the second sun gear 22e around the motor axis J. On the radially outer side of the second sun gear 22e, an annular second internal gear 22f is provided around the motor axis J. A plurality of second planetary gears 22g are meshed between the second sun gear 22e and the second internal gear 22f. The second planetary gears 22g are connected to the second planetary carrier 22h arranged in front of the second sun gear 22e. The second planetary carrier 22h is integrally provided with the rear end of the gear shaft 23 in front, and can rotate around the motor axis J. Therefore, the rotational drive of the first planetary carrier 22d is reduced and transmitted to the gear shaft 23 through the second sun gear 22e, the second planetary gears 22g, and the second planetary carrier 22h. In this way, the rotational drive of the motor shaft 20a is reduced and transmitted to the gear shaft 23 through the planetary reduction mechanism 22.

[0046] like Fig.12 As shown, the gear shaft 23 is supported by bearings 23b and 23c so as to be rotatable around the motor axis J. The front bearing 23b is pressed into a recessed portion 13c provided in a lower portion of the first central mechanism housing 13. The rear bearing 23c is pressed into a recessed portion 14c provided in a lower portion of the second central mechanism housing 14. The gear shaft 23 has a driving side gear 23a between the bearings 23b and 23c in the front-rear direction. The driving side gear 23a is integral with the gear shaft 23 and rotates around the motor axis J.

[0047] like Fig.12 As shown in FIG. 1 , an idler gear 24 is provided between the gear shaft 23 and the output shaft 27 in the vertical direction. The idler gear 24 is supported by a cylindrical shaft member 24a extending in the front-rear direction so as to be rotatable about the axis of the shaft member 24a. The shaft member 24a is inserted into a through hole 13d provided in the lower extension portion 13b of the first central mechanism housing 13 and a through hole 14d provided in the lower extension portion 14b of the second central mechanism housing 14. The axis of the shaft member 24a is located on a virtual plane S including the motor axis J and the output axis K (see FIG. 1 ). Fig. 9 ). A radial bearing 24b is provided in the radial direction between the shaft member 24a and the idler gear 24. The idler gear 24 meshes with the driving side gear 23a at the bottom and meshes with the driven side gear 26a at the top.

[0048] like Fig.12As shown, a feed screw mechanism (power conversion mechanism) 25 called a ball screw mechanism is provided on the tool body 10. The feed screw mechanism 25 has an output shaft 27 and a nut 26. An external thread 27a is provided on the outer peripheral surface of the output shaft 27. Therefore, the output shaft 27 is equivalent to the screw shaft of the ball screw mechanism. The nut 26 is formed into a substantially cylindrical shape covering the output shaft 27 in the circumferential direction. An internal thread 26b is provided on the inner peripheral surface of the nut 26. The internal thread 26b is screwed with the external thread 27a between it and the external thread 27a of the output shaft 27 through a plurality of balls 27b. On the outer periphery of the nut 26, a driven side gear 26a that protrudes radially outward and meshes with the idler 24 is provided. The rotational drive of the gear shaft 23 is decelerated and transmitted to the nut 26 by the meshing of the driving side gear 23a with the idler 24 and the meshing of the idler 24 with the driven side gear 26a.

[0049] like Fig.12 As shown, the nut 26 is supported by bearings 26c and 26d housed in the tool body 10 so as to be rotatable about the output axis K. The front bearing 26c is pressed into the inner peripheral surface 13a of the first central mechanism housing 13. The rear bearing 26d is pressed into the inner peripheral surface 14a of the second central mechanism housing 14. A thrust bearing 26e is provided between the rear surface of the nut 26 and the front surface 15a of the rear side mechanism housing 15 to bear the thrust load pressing the nut 26 forward.

[0050] like Figure 3 , Figure 5 As shown, an output shaft guide 28 is installed at the rear of the output shaft 27 to prevent the output shaft 27 from rotating and to guide the output shaft 27 to move forward and backward. The output shaft guide 28 has a roller shaft 28a connected to the rear end of the output shaft 27 and extending in the left-right direction. The output shaft guide 28 has a pair of rollers 28b at the left and right ends of the roller shaft 28a. A pair of annular tracks 28c extending in the front-back direction are installed on the left and right side parts of the second central mechanism housing 14. The roller 28b can engage with the track 28c and move along the track 28c in the front-back direction. The output shaft 27 is guided by the roller 28b and moves in the front-back direction together with the output shaft guide 28.

[0051] like Figure 6 , Fig.12As shown, the tool body 10 has a claw rotating mechanism 30 that rotates the plurality of claws 4. The plurality of claws 4 rotate around the axis of the output axis K. The claw rotating mechanism 30 has a push plate 34 that moves forward and backward in conjunction with the rotation of the motor shaft 20a, and a transmission shaft 31 that rotates in conjunction with the forward and backward movement of the push plate 34. The transmission shaft 31 is arranged on a transmission shaft axis L extending in the front-to-back direction. The transmission shaft 31 rotates around the transmission shaft axis L. The transmission shaft axis L is located below the output axis K and above the motor axis J in the up-down direction. The transmission shaft axis L is offset in the left-right direction to a position to the left of the imaginary plane S containing the output axis K and the motor axis J (refer to Fig.13 ). A portion of the transmission shaft 31 of the claw rotating mechanism 30 overlaps with the idler gear 24 in the vertical direction. More than 80% of the axial length (front-rear direction) of the transmission shaft 31 overlaps with the output shaft 27 at the rear end. In this embodiment, the entire axial length of the transmission shaft 31 overlaps with the output shaft 27 at the rear end.

[0052] like Figure 5 , Fig.14 As shown, the claw rotating mechanism 30 has a ball holding portion 36 mounted on the transmission shaft 31. The ball holding portion 36 can move in the front-to-back direction along the transmission shaft axis L. On the right side of the transmission shaft 31, a guide shaft 41 extending parallel to the transmission shaft 31 is provided. The second central mechanism housing 14 has a guide shaft support portion 14e below the output shaft 27 and above the planetary reduction mechanism 22. A through hole 14f penetrating in the front-to-back direction is provided in the guide shaft support portion 14e. The guide shaft 41 is pressed into the through hole 14f and fixed to the second central mechanism housing 14.

[0053] like Figure 5 , Fig.10 As shown, the ball retaining portion 36 has a roughly cylindrical sleeve mounting portion 36a and a lateral extension portion 36e extending to the right side of the sleeve mounting portion 36a. In the center of the sleeve mounting portion 36a, an axial insertion hole 36c is provided that penetrates in the front-to-back direction. The transmission shaft 31 is inserted into the axial insertion hole 36c in a manner that allows it to slide relative to the ball retaining portion 36. A through hole 36f that penetrates in the front-to-back direction is provided in the lateral extension portion 36e. The guide shaft 41 is inserted into the through hole 36f in a manner that allows it to slide relative to the ball retaining portion 36. In this way, the ball retaining portion 36 can be guided by the transmission shaft 31 and the guide shaft 41 to slide in the front-to-back direction, and the rotation around the axis of the transmission shaft 31 is restricted.

[0054] like Figure 5 , Fig.14As shown, the claw rotating mechanism 30 has a push plate 34 that pushes the ball retaining portion 36 from the rear. The plate-shaped push plate 34 is integrally mounted on the roller shaft 28a in a posture with the plate thickness direction as the front-to-back direction. The push plate 34 extends downward from the roller shaft 28a and is arranged behind the sleeve mounting portion 36a. The push plate 34 has a through hole 34a that passes through in the front-to-back direction. The transmission shaft 31 protruding rearward from the sleeve mounting portion 36a can pass through the through hole 34a. When the push plate 34 moves forward together with the output shaft 27, it presses the rear surface of the ball retaining portion 36 forward. When the push plate 34 moves rearward together with the output shaft 27, it moves in a manner away from the ball retaining portion 36. Therefore, the force of the push plate 34 to move the ball retaining portion 36 does not work.

[0055] like Fig.10 , Fig.14 As shown, a ball retaining hole 36b is provided in the sleeve mounting portion 36a, which penetrates in the up-down direction and communicates with the shaft insertion hole 36c. Balls 39 are respectively inserted into a pair of ball retaining holes 36b located on the upper and lower sides of the shaft insertion hole 36c. A sleeve 37 is installed in the sleeve mounting portion 36a, which covers the ball retaining hole 36b from the radial outer side. By installing the sleeve 37 in the sleeve mounting portion 36a, the ball 39 is retained in the ball retaining hole 36b. A groove 36d extending in the circumferential direction is provided in the front portion of the sleeve mounting portion 36a. In the groove 36d, an O-ring 38 is installed to prevent the sleeve 37 from falling off from the sleeve mounting portion 36a.

[0056] like Fig.14 , Fig.15 As shown, the transmission shaft 31 is constructed by assembling a front shaft 32 and a rear shaft 33 together in the front-to-back direction. The front shaft 32 is supported by the first central mechanism housing 13 and the second central mechanism housing 14 in a manner that allows rotation around the axis. The rear shaft 33 is supported by the second central mechanism housing 14 in a manner that allows rotation around the axis. The rear shaft 33 is inserted into the ball retaining portion 36. An external thread 33a is provided at the front end of the rear shaft 33. An internal thread 32a that screws with the external thread 33a is provided on the front shaft 32. By screwing the external thread 33a with the internal thread 32a, the rear shaft 33 is integrally mounted on the front shaft 32. By rotating the rear shaft 33 relative to the front shaft 32 in the clockwise direction (as viewed from the rear) Figure 8 The outer thread 33a and the inner thread 32a are tightened to each other by rotating the rear shaft 33 in the counterclockwise direction (as viewed from the rear) relative to the front shaft 32. Figure 7 By rotating in the direction of the second rotation R2 shown in the figure, the external thread 33a and the internal thread 32a are loosened from each other.

[0057] like Fig.10 , Fig.14 , Fig.15As shown in FIG. 1 , a pair of ball grooves 33b are provided on the outer peripheral surface of the rear shaft 33. The ball grooves 33b extend approximately along the length direction of the rear shaft 33 and extend circumferentially from the rear to the front like a thread groove. The ball grooves 33b extend from the rear portion 33c to the front portion 33e along the first rotation R1 (refer to FIG. 1 ). Figure 8 ) direction. A pair of ball grooves 33b are arranged in a point-symmetrical positional relationship with respect to the axial center of the rear axle 33. The balls 39 protruding radially inward from the ball retaining hole 36b of the ball retaining portion 36 toward the shaft insertion hole 36c are engaged with the ball grooves 33b.

[0058] like Fig.14 , Fig.15 As shown in FIG. 1 , the ball 39 moves in the ball groove 33b along the extension direction of the ball groove 33b. In addition, the ball 39 is held by the ball holding portion 36 whose rotation around the transmission shaft axis L is restricted. When the ball holding portion 36 is moved forward relative to the rear axle 33, the ball 39 moves from the rear portion 33c of the ball groove 33b to the front portion 33e. Therefore, the rear axle 33 rotates R2 (refer to FIG. 1 ) relative to the ball holding portion 36. Figure 7 When the ball holding portion 36 is moved rearward relative to the rear shaft 33, the ball 39 moves from the front portion 33e to the rear portion 33c of the ball groove 33b. Therefore, the rear shaft 33 rotates in the first direction R1 (see Figure 8 ) direction.

[0059] like Fig.14 , Fig.15 As shown, the second central mechanism housing 14 has a transmission shaft support portion 14h that supports the area where the front shaft 32 and the rear shaft 33 are screwed together. The transmission shaft support portion 14h is provided with a rib-shaped spring receiving portion 14g protruding in the radial direction and a through hole 14i that penetrates in the front-to-back direction and can insert the transmission shaft 31. A compression spring 40 is provided between the spring receiving portion 14g and the ball holding portion 36 in the front-to-back direction. The rear shaft 33 is inserted in the center of the compression spring 40. The compression spring 40 urges the ball holding portion 36 to the rear.

[0060] like Fig.14 , Fig.15 As shown, the first central mechanism case 13 has a transmission shaft support portion 13e that supports the front shaft 32. A through hole 13f that penetrates in the front-rear direction and through which the front shaft 32 can be inserted is provided at the center of the transmission shaft support portion 13e.

[0061] like Fig.14 , Fig.15As shown, the claw rotation mechanism 30 has a cylindrical one-way clutch 42 and a drive side gear 43. The one-way clutch 42 and the drive side gear 43 are installed in front of the front shaft 32 in front of the transmission shaft support portion 13e. The one-way clutch 42 is provided between the front shaft 32 and the drive side gear 43 in the radial direction. The one-way clutch 42 is, for example, a structure called a wedge type, and transmits only the rotation in one direction of the radial inner peripheral surface side to the radial outer peripheral surface side. The one-way clutch 42 transmits the first rotation R1 (refer to Figure 8 ) is transmitted to the driving side gear 43. The one-way clutch 42 does not transmit the second rotation R2 (refer to Figure 7 ) is transmitted to the driving side gear 43 to cause the front axle 32 to idle.

[0062] like Fig.11 As shown, the rear shaft 33, the ball holding portion 36, the ball 39, and the sleeve 37 can be integrally assembled into an assembly 35. The assembly 35 is assembled to the tool body 10 by screwing the external thread 33a of the rear shaft 33 and the internal thread 32a of the front shaft 32. When the assembly 35 is assembled to the tool body 10, the assembly 35 is assembled in such a manner that the compression spring 40 is compressed.

[0063] like Figure 7 , Figure 8 , Fig.11 As shown, a width across flats portion 32b is provided at the rear portion of the front shaft 32, and the width across flats portion 32b has a pair of flat surfaces extending parallel to each other in the front-to-back direction. The width across flats portion 32b is exposed to the outside of the mechanism housing between the first central mechanism housing 13 and the second central mechanism housing 14. A width across flats portion 33f is provided at the rear end of the rear shaft 33, and the width across flats portion 33f has a pair of flat surfaces extending parallel to each other in the front-to-back direction. While the width across flats portion 32b is held by a wrench or the like to prevent the front shaft 32 from rotating, the width across flats portion 33f is held by a wrench or the like to rotate the rear shaft 33 in the direction of the first rotation R1. Accordingly, the rear shaft 33 is screwed together with the front shaft 32. In this way, the assembly 35 having the rear shaft 33 can be integrally assembled to the tool body 10 supporting the front shaft 32.

[0064] like Figure 4 , Fig.12 , Fig.16 , Fig.17As shown, the claw rotating mechanism 30 has a roughly cylindrical rotating drive ring 44 and a roughly cylindrical joint 45. The rotating drive ring 44 and the joint 45 are supported on the radial inner side of the inner circumferential surface 12b of the front mechanism housing 12, and rotate around the axis with the output axis K as the center. An O-ring 45d is provided between the joint 45 and the front mechanism housing 12 in the radial direction. In the center of the rotating drive ring 44, a through hole 44b is provided that penetrates in the front-to-back direction and can penetrate the output shaft 27. On the rear outer periphery of the rotating drive ring 44, a driven side gear 44a extending radially outward is provided. The driving side gear 43 meshes with the driven side gear 44a. The rotating power of the driving side gear 43 is decelerated and transmitted to the driven side gear 44a. At the front end of the rotating drive ring 44, a plurality of engaging protrusions 44c protruding forward and arranged circumferentially are provided.

[0065] like Figure 4 , Fig.16 , Fig.17 As shown, in the center of the joint 45, a through hole 45a is provided which penetrates in the front-to-back direction and through which the output shaft 27 can be inserted. At the rear end of the joint 45, a plurality of engaging recesses 45b are provided which engage with the plurality of engaging protrusions 44c of the rotation drive ring 44. The joint 45 rotates integrally with the rotation drive ring 44 by the engagement of the engaging protrusions 44c and the engaging recesses 45b. At the front end of the joint 45, a plurality of engaging protrusions 45c which protrude forward and are arranged in the circumferential direction are provided.

[0066] like Figure 4 , Fig.16 , Fig.17 As shown, at the rear end of the claw 4, there is provided an engaging recess 4b that engages with a plurality of engaging protrusions 45c of the joint 45. The claw 4 and the joint 45 rotate integrally around the axis of the output axis K by fitting the plurality of engaging protrusions 45c with the engaging recesses 4b of each claw 4. A ring receiving groove 4a having a circular arc cross section is provided at the radial outer periphery of the rear portion of the claw 4. The ring receiving grooves 4a of the plurality of claws 4 are connected in the circumferential direction to form an annular groove. The plurality of claws 4 are connected in the circumferential direction by the ring 4c that is inserted into the ring receiving groove 4a and can be elastically extended. On the inner circumferential surface of the end cover 2, a claw support groove 2a that can accommodate the ring 4c is provided to extend radially outward and in the circumferential direction. The claw support groove 2a allows the ring 4c to move in the radial direction, but restricts the ring 4c from moving in the front-rear direction. The plurality of claws 4 open and close in the radial direction with the ring 4c supported in the claw support groove 2a as the center.

[0067] like Fig.14 , Fig.15As shown in FIG. 1 , a magnet 46 is mounted on the upper portion of the roller shaft 28a. An initial position (rear end position) sensor 47 and a terminal position (front end position) sensor 48 are provided on the upper inner circumference of the main body housing 11. The initial position sensor 47 and the terminal position sensor 48 are sensors for detecting magnetic fields, which are called Hall ICs. Fig.14 As shown in FIG. 1 , the initial position sensor 47 is arranged at a position directly above the magnet 46 when the output shaft 27 is at the rear end position (initial position). When the front and rear positions of the magnet 46 reach a position corresponding to the initial position sensor 47, the initial position sensor 47 sends a signal. That is, the initial position sensor 47 detects the rear end position (initial position) of the output shaft 27 and sends a signal to the controller 9 (refer to FIG. 1 ). Figure 1 ) sends a signal. Fig.15 As shown in FIG. 1 , the terminal position sensor 48 is arranged at a position directly above the magnet 46 when the output shaft 27 is at the front end position. When the front and rear positions of the magnet 46 reach a position corresponding to the terminal position sensor 48, the terminal position sensor 48 sends a signal. That is, the terminal position sensor 48 detects the front end position (terminal position) of the output shaft 27 and sends a signal to the controller 9.

[0068] Next, the driving of the feed screw mechanism 25 and the claw rotating mechanism 30 will be described. Fig.12 First, by the detent operation of the operating member 6, the motor shaft 20a of the motor 20 rotates. The rotational drive of the motor shaft 20a is decelerated by the planetary reduction mechanism 22 and then transmitted to the gear shaft 23. When the gear shaft 23 rotates, the idler gear 24 meshing with the driving side gear 23a rotates. And the nut 26 rotates around the axis of the output axis K together with the driven side gear 26a meshing with the idler gear 24. When the nut 26 rotates, the internal thread 26b is screwed with the external thread 27a, and the output shaft guide 28 prevents the output shaft 27 from rotating, accordingly, the output shaft 27 is rotated as described with reference to FIG. Figure 7 , Figure 8 Move in the forward and backward direction as shown. Fig.16 , Fig.17 When the output shaft 27 moves forward, the wedge 3 installed at the front end of the output shaft 27 presses the plurality of claws 4 and the ring 4c to move them to the radially outer open position. When the output shaft 27 moves backward, the pressing force of the wedge 3 is eliminated, so the ring 4c contracts and the plurality of claws 4 return to the radially inner closed position. For example, the plurality of claws 4 are moved from Fig.15 The mutually separated positions shown are Fig.14 The positions shown are moved towards or abutting each other.

[0069] Reference Fig.12The motor 20 switches forward and reverse rotation through the controller 9. The output shaft 27 moves forward when the motor 20 rotates forward, and moves backward when the motor 20 rotates reversely. The controller 9 switches forward and reverse rotation of the motor 20 according to the signal sent from the initial position sensor 47 and the signal sent from the terminal position sensor 48.

[0070] The motor 20 switches forward and reverse rotation by the controller 9. The output shaft 27 moves forward when the motor 20 rotates forward, and moves backward when the motor 20 rotates reversely. The controller 9 switches forward and reverse rotation of the motor 20 according to a signal sent from the initial position sensor 47 and a signal sent from the terminal position sensor 48.

[0071] Reference Figure 7 , Figure 8 When the output shaft 27 moves forward, the push plate 34 mounted on the roller shaft 28a also moves forward integrally. The push plate 34 overcomes the biasing force of the compression spring 40 and presses the ball retaining portion 36 forward. When the ball retaining portion 36 moves forward, Fig.14 , Fig.15 , the ball 39 engages with the ball groove 33b. Figure 7 , Figure 8 , the ball retaining portion 36 is prevented from rotating by the guide shaft 41, and the rear shaft 33 rotates in the direction of the second rotation R2. The front shaft 32 that is screwed with the rear shaft 33 also rotates in the direction of the second rotation R2. At this time, the one-way clutch 42 does not transmit the rotational power of the front shaft 32 to the driving side gear 43. Therefore, the front shaft 32 rotates in the direction of the second rotation R2 that loosens the screwing with the rear shaft 33, but due to idling, the torque that loosens the screwing is suppressed. The rotating drive ring 44 with the driven side gear 44a does not rotate because the rotational power is not transmitted from the driving side gear 43. Therefore, the joint 45 and the multiple claws 4 connected to the rotating drive ring 44 do not rotate. In this way, the multiple claws 4 do not rotate around the axis of the output axis K, and are pressed by the wedge 3 to open radially outward.

[0072] Reference Figure 7 , Figure 8 When the output shaft 27 moves backward, the push plate 34 mounted on the roller shaft 28a also moves backward integrally. The pressing force of the push plate 34 is released, and the ball retaining portion 36 is urged by the compression spring 40 to move backward. When the ball retaining portion 36 moves backward, Fig.14 , Fig.15 , the ball 39 engages with the ball groove 33b. Figure 7 , Figure 8, the guide shaft 41 prevents the ball retaining portion 36 from rotating, and accordingly the rear shaft 33 rotates in the direction of the first rotation R1. The front shaft 32 that is screwed with the rear shaft 33 also rotates in the direction of the first rotation R1. At this time, the one-way clutch 42 transmits the rotational power of the front shaft 32 to the driving side gear 43. Therefore, the front shaft 32 rotates in the direction of the first rotation R1, which further tightens the screwing with the rear shaft 33. Fig.16 , Fig.17 The rotation drive ring 44 having the driven side gear 44a rotates in the clockwise direction when viewed from the front by receiving the rotational power transmitted from the driving side gear 43. The joint 45 and the plurality of claws 4 also rotate integrally with the rotation drive ring 44. In this way, the plurality of claws 4 rotate from Fig.17 Position to Fig.16 That is, the plurality of claws 4 are closed radially inward while rotating around the axis of the output axis K in the clockwise direction as viewed from the front.

[0073] As described above, by the triggering operation of the operating member 6, the motor 20 is started to perform the opening and closing action and the rotation action of the jaws 4. In the pipe expanding tool 1 of this example, during the operation of the operating member 6, the opening and closing action and the rotation action of the jaws 4 are performed multiple times continuously by repeating the forward and reverse rotation of the motor 20. A control circuit C for repeating the forward and reverse rotation of the motor 20 is provided on the control substrate 9a of the controller 9. The control substrate 9a includes a power supply circuit for supplying power from the battery 8 to the motor 20.

[0074] like Fig.18 As shown, in addition to the on-operation signal of the operating member 6, the on-signal of the initial position sensor 47, and the on-signal of the terminal position sensor 48, the rotation speed information of the rotation speed detection sensor 20d and the set number of times information based on the operation of the operation panel 7b are input to the control circuit C. The control substrate 9a includes a detection circuit for detecting the rotation speed of the motor 20 by the rotation speed detection sensor 20d. The number of opening and closing actions (reciprocating actions of the output shaft 27) of the plurality of claws 4 is set by the user operating the operation panel 7b in advance. The information of the set number of actions is stored in the control circuit C as the set number of times P. The set number of times P of the opening and closing actions of the claws 4 is appropriately set according to the object of the diameter expansion operation, that is, the PEX pipe 51.

[0075] Fig.19 1 shows a series of operation flows of the pipe expanding tool 1 controlled by the control circuit C. By installing the battery 8 in the battery installation portion 7a, the operation flow enters the start standby state (step 100, hereinafter referred to as ST100). When the operating member 6 is pulled in ST101, the position of the output shaft 27 is detected (ST102). In ST102, by determining the on / off state of the initial position sensor 47, it is determined whether the output shaft 27 is in the initial position.

[0076] When it is confirmed in ST102 that the output shaft 27 is not at the initial position (the initial position sensor 47 is turned off), the motor 20 is reversed in ST103. Accordingly, the output shaft 27 is first returned to the initial position at the rear. When it is confirmed in ST102 that the output shaft 27 is at the initial position (the initial position sensor 47 is turned on), the motor 20 is forwardly rotated in ST104. Accordingly, the output shaft 27 advances and the plurality of claws 4 open.

[0077] During the forward rotation of the motor 20, the detent operation of the operating member 6 (the on state of the switch body 6a) is confirmed in ST105. The detent operation of the operating member 6 is confirmed, the forward rotation of the motor 20 continues, and the claws 4 are opened. When the output shaft 27 reaches the terminal position in ST106, the terminal position sensor 48 is turned on. Accordingly, the plurality of claws 4 are in a state of being fully opened.

[0078] If the detent operation of the operating member 6 is not confirmed in ST105 during the opening action of the claw 4, it is determined that the user has released the detent operation of the operating member 6. In this case, the motor 20 is switched to reverse in ST110. Accordingly, the output shaft 27 starts to move backward during the forward movement, and the opening action of the claw 4 is stopped on the way. When the initial position of the output shaft 27 is confirmed in ST111, the motor 20 is stopped in ST112. In this way, when the detent operation of the operating member 6 is released during the opening action of the claw 4, the motor 20 is reversed and the output shaft 27 returns to the initial position. Accordingly, the claw 4 returns to the closed state, and the control flow returns to the standby state of ST100.

[0079] like Fig. 20 As shown, for example, at the stage where the output shaft 27 reaches the terminal position and the diameter expansion action is completed by the claws 4, the number of times the terminal position sensor 48 is turned on (the number of times the diameter expansion action is executed p) is counted. In ST107, the counted execution number p is compared with the preset number P. When the execution number p of the opening action of the claws 4 is less than the set number P (p<P), the motor 20 is reversed (ST108). Accordingly, the output shaft 27 retreats and the plurality of claws 4 are closed. In the closing stage of the claws 4, they are rotated around the output axis K by the claw rotating mechanism 30.

[0080] In ST109, the detent operation state of the operating member 6 during the reverse rotation of the motor 20 is determined. If the detent operation of the operating member 6 is not confirmed in ST109, the control flow returns to ST110. Therefore, at the time point when the motor 20 continues to reverse and the output shaft 27 returns to the initial position, the motor 20 stops. Accordingly, the user's operation is terminated and the control flow returns to the standby state of ST100.

[0081] When the detent operation state of the operating part 6 is confirmed in ST109, the control flow returns to ST102. In ST102, the initial position of the output shaft 27 is confirmed based on the on signal of the initial position sensor 47. When the output shaft 27 reaches the initial position and the closed state of multiple claws 4 is confirmed, the motor 20 is switched to forward rotation again in ST104. Accordingly, the second opening action of the claw 4 begins. Thereafter, the motor 20 rotates forward and the claw 4 opens again, conditional on the detent operation of the operating part 6 being confirmed in ST105 until the output shaft 27 reaches the terminal position in ST106. In addition, the motor 20 reverses and the claw 4 closes, conditional on the detent operation of the operating part 6 being confirmed in ST109 until the output shaft 27 reaches the initial position in ST102.

[0082] In this way, the opening action of the plurality of claws 4 is repeated and the execution times p are accumulated one by one. After ST107, it is confirmed in ST120 that the execution times p reaches the set times P (p=P). When it is confirmed in ST120 that p=P, the motor 20 is switched to reverse rotation in ST121 and the output shaft 27 moves backward. Accordingly, the claws 4 are closed while rotating around the output axis K.

[0083] In the stage of reverse rotation of the motor 20 in ST121 (the final stage of the set number of times P), unlike the reverse rotation stage in ST108 (the stage during the set number of times P), the detent operation of the operating member 6 is not confirmed. In the reverse rotation stage in ST121, regardless of the operating state of the operating member 6, the reverse rotation of the motor 20 continues and the output shaft 27 returns to the initial position, after which the motor 20 stops.

[0084] When the initial position of the output shaft 27 is confirmed in ST122 and the closed state of the plurality of claws 4 is confirmed, the motor 20 is stopped in ST123. Thereafter, the detent operation of the operating member 6 is released in ST124, and a series of control operations are completed.

[0085] As described above, in this embodiment, the forward and reverse rotations of the motor 20 are switched, and the output shaft 27 reciprocates between the initial position and the terminal position multiple times. Accordingly, when the operating member 6 is pulled once, the opening and closing actions of the claw 4 are repeated. Therefore, the burden on the user is reduced.

[0086] According to the embodiment, the initial position and the final position of the output shaft 27 (screw shaft) are detected by the initial position sensor 47 and the final position sensor 48, respectively. Thus, the reciprocating motion of the output shaft 27 is performed quickly and reliably.

[0087] According to the embodiment, after the triggering operation of the operating member 6 (operating member) is released, the motor 20 is reversed to return the output shaft 27 (screw shaft) to the initial position (ST110, ST111). Therefore, when the operation of the operating member 6 is released during the set number of times P, the output shaft 27 returns to the initial position and the claw 4 reliably returns to the closed position. Accordingly, the next operation can be performed quickly.

[0088] According to the embodiment, when the output shaft 27 is not at the initial position when the operation of the operating member 6 is started, the motor 20 is temporarily reversed and the output shaft 27 returns to the initial position. Therefore, the output shaft 27 is prevented from advancing from the midway position. According to this, the opening action of the claw does not start from the half-open state, but always starts from the closed position. Therefore, the diameter expansion operation can be performed efficiently.

[0089] According to the embodiment, during the detent operation of the operating member 6, the number of reciprocating movements p between the initial position and the terminal position of the output shaft 27 is measured. When the number of reciprocating movements p reaches a preset number of times P, the rotation of the motor 20 is stopped. Therefore, even during the detent operation of the operating member 6, at the time point when the opening movement of the claw 4 is performed the set number of times P, the motor 20 is automatically stopped. Accordingly, an appropriate diameter expansion movement can be quickly performed.

[0090] According to the embodiment, when the number of executions p of the reciprocating action of the output shaft 27 reaches a preset number of times P (ST120), the motor 20 is reversed to stop the output shaft 27 at the initial position (ST121). After the output shaft 27 returns to the initial position (ST122), the motor 20 stops (ST123). Therefore, when the opening action of the plurality of claws 4 is performed for the set number of times P, the motor 20 automatically stops after the output shaft 27 returns to the initial position. Accordingly, the next diameter expansion action can be started quickly.

[0091] According to the embodiment, the initial position and the terminal position of the output shaft 27 are detected by the Hall IC sensors (initial position sensor 47 and terminal position sensor 48). Therefore, the accuracy and compactness of the detection device for detecting the initial position and the terminal position of the output shaft 27 are ensured.

[0092] According to the embodiment, the tube expanding tool 1 has a feed screw mechanism 25 (ball screw) provided with balls 27b between an output shaft 27 (screw shaft) and a nut 26 (internal thread member). Therefore, the output shaft 27 is smoothly and smoothly screwed with the nut 26. Accordingly, the output shaft 27 reciprocates accurately and smoothly.

[0093] As described above, the pipe expansion tool 1 for expanding the end of a synthetic resin fluid pipe is Fig.12As shown, the tube expansion tool 1 has a motor shaft 20a that is rotated by a motor 20. The tube expansion tool 1 has a feed screw mechanism (power conversion mechanism) 25 that converts the rotation of the motor shaft 20a into forward and backward movement of the output shaft 27. The tube expansion tool 1 has a plurality of claws 4 that are pressed by a wedge 3 provided at the front of the output shaft 27 and open radially outward from each other. The tube expansion tool 1 has a claw rotation mechanism 30 that has a transmission shaft 31 that rotates around the axis in conjunction with the rotation of the motor shaft 20a, and the plurality of claws 4 are rotated around the axis by the transmission shaft 31. The output shaft 27, the motor shaft 20a, and the transmission shaft 31 of the claw rotation mechanism 30 are arranged in parallel with each other and overlapped in the front-back direction.

[0094] Therefore, by arranging the output shaft 27, the motor shaft 20a, and the transmission shaft 31 of the claw rotating mechanism 30 in an overlapping manner in the front-to-back direction, the tube expanding tool 1 can be compactly arranged in the front-to-back direction. Furthermore, the output shaft 27, the motor shaft 20a, and the transmission shaft 31 are arranged in parallel with each other. Therefore, the tube expanding tool 1 can be compactly arranged in the up-down direction or the left-right direction intersecting the front-to-back direction.

[0095] like Fig.12 , Fig.14 As shown in the figure, the transmission shaft 31 of the claw rotating mechanism 30 and the motor 20 are arranged so that more than 80% of their axial lengths overlap with the output shaft 27 at the rear end in the front-to-back direction. Therefore, the protrusion amount of the transmission shaft 31 of the claw rotating mechanism 30 and the motor 20 relative to the output shaft 27 in the front-to-back direction is suppressed, and in particular, the protrusion amount relative to the output shaft 27 at the rear end is suppressed. According to this, the compactness of the pipe expanding tool 1 in the front-to-back direction can be improved.

[0096] like Fig.12 , Fig.14 As shown in the figure, the transmission shaft 31 of the claw rotating mechanism 30 and the motor 20 are arranged so that their respective axial full lengths overlap with the output shaft 27 at the rear end in the front-rear direction. Therefore, the transmission shaft 31 of the claw rotating mechanism 30 and the motor 20 do not protrude in the front-rear direction relative to the output shaft 27 at the rear end. According to this, the compactness of the pipe expanding tool 1 in the front-rear direction can be further improved.

[0097] like Fig.12As shown in FIG. 1 , the tube expansion tool 1 has a planetary reduction mechanism (speed change mechanism) 22 for changing the speed of the rotation output of the motor shaft 20a. The tube expansion tool 1 has an idler gear 24 provided between the planetary reduction mechanism 22 and the feed screw mechanism 25. Therefore, by providing the idler gear 24 between the planetary reduction mechanism 22 and the feed screw mechanism 25, the planetary reduction mechanism 22 can be arranged overlapping with the feed screw mechanism 25 in the front-to-back direction. Therefore, the motor 20 provided near the planetary reduction mechanism 22 can be arranged close to the feed screw mechanism 25. According to this, the tube expansion tool 1 can be compactly provided in the front-to-back direction.

[0098] like Fig.13 As shown in FIG. 1 , the output shaft 27 and the motor shaft 20a are offset in the up-down direction perpendicular to the front-back direction. The claw rotating mechanism 30 is located between the output shaft 27 and the motor shaft 20a in the up-down direction when viewed in the axial direction of the output shaft 27. Therefore, the output shaft 27, the claw rotating mechanism 30, and the motor 20 can be compactly arranged in the up-down direction perpendicular to the front-back direction in addition to the up-down direction. Therefore, it is possible to suppress the tube expanding tool 1 from becoming longer in the up-down direction.

[0099] like Fig.13 As shown, the claw rotating mechanism 30 is offset with respect to the virtual plane S including both the motor shaft 20a and the output shaft 27. Therefore, the output shaft 27, the claw rotating mechanism 30, and the motor 20 can be compactly arranged in the vertical direction in which the virtual plane S in which the motor shaft 20a and the output shaft 27 are arranged extends. Accordingly, the pipe expanding tool 1 can be compactly arranged in the vertical direction.

[0100] like Fig.11 , Fig.14 As shown, the claw rotation mechanism 30 has a one-way clutch 42. The one-way clutch 42 and the first rotation R1 (see Figure 8 ) are rotated in conjunction with each other to rotate the plurality of claws 4, and the second rotation R2 (refer to Figure 7 ) linkage. The transmission shaft 31 of the claw rotating mechanism 30 has a rear shaft 33 and a front shaft 32 screwed with the front part of the rear shaft 33. Therefore, the transmission shaft 31 of the claw rotating mechanism 30 can be separated into the rear shaft 33 and the front shaft 32, wherein the rear shaft 33 is assembled to the component 35 for rotating the transmission shaft 31; the front shaft 32 is assembled to the tool body 10 in order to transmit the rotation drive of the transmission shaft 31 to the plurality of claws 4. The tool body 10 on the side of the front shaft 32 and the component 35 on the side of the rear shaft 33 are assembled separately, and after assembly, the front shaft 32 and the rear shaft 33 are connected in the front-to-back direction by screwing. Accordingly, the assemblability of the transmission shaft 31 can be improved.

[0101] like Fig.14 , Fig.15As shown, the front shaft 32 is screwed with respect to the rear shaft 33 to rotate at the first rotation R1 (refer to Figure 8 ) direction to the rear axle 33. Therefore, when the front axle 32 performs the first rotation R1, the torque is transmitted from the front axle 32 to the plurality of claws 4 through the one-way clutch 42, and the torque acts in the direction in which the rear axle 33 is fastened to the front axle 32. Therefore, the fastening force between the rear axle 33 and the front axle 32 becomes stronger. On the other hand, when the front axle 32 performs the second rotation R2 (refer to Figure 7 ), the torque transmitted from the front shaft 32 to the plurality of claws 4 is a small amount. Therefore, the front shaft 32 is almost free from resistance and rotates idly, performing the second rotation R2. The rear shaft 33 rotates in the loosening direction relative to the front shaft 32, but no resistance is applied to the front shaft 32, so the fastening to the front shaft 32 is not loosened and rotates. In this way, the loosening of the front shaft 32 and the rear shaft 33 due to the operation of the claw rotating mechanism 30 can be suppressed.

[0102] like Fig.12 As shown in the figure, the power conversion mechanism is a feed screw mechanism 25, and the feed screw mechanism 25 has an external thread 27a provided on the outer periphery of the output shaft 27, and a nut 26 penetrated by the external thread 27a. Therefore, the feed screw mechanism 25 can be provided around the output shaft 27. Therefore, it is possible to suppress the feed screw mechanism 25 from protruding in the front-rear direction relative to the output shaft 27. According to this, the pipe expansion tool 1 can be compactly provided in the front-rear direction.

[0103] like Fig.12 As shown, the tube expanding tool 1 has a handle 5 extending in a direction intersecting the axial direction of the output shaft 27. At least a portion of the nut 26 of the feed screw mechanism 25 and at least a portion of the motor 20 overlap with the handle 5 in the front-to-back direction. Therefore, the nut 26 of the feed screw mechanism 25 and the motor 20 can be arranged near the support center when the user holds the handle 5 to support the tube expanding tool 1. According to this, the weight balance of the tube expanding tool 1 in the front-to-back direction can be improved.

[0104] Various modifications can be added to the tube expanding tool 1 of the present embodiment described above. The tube expanding tool 1 having six claws 4 is exemplified. Alternatively, for example, the number of claws 4 may be 5 or less or 7 or more.

[0105] The structure in which the transmission shaft 31 of the claw rotating mechanism 30 and the motor 20 overlap the output shaft 27 at the rear end position in the full length in the front-to-back direction is exemplified. As an alternative, the transmission shaft 31 of the claw rotating mechanism 30 and the motor 20 may overlap the output shaft 27 at the rear end position in a length of, for example, 80% or 90% of the full length in the front-to-back direction. The structure in which the transmission shaft axis L is offset to the left of the imaginary plane S including the motor axis J and the output axis K is exemplified. As an alternative, the transmission shaft axis L may be offset to the right of the imaginary plane S including the motor axis J and the output axis K. The imaginary plane S including the motor axis J and the output axis K may also extend obliquely relative to the up-down direction. The structure in which the motor axis J, the output axis K, and the transmission shaft axis L are parallel to each other is exemplified. As an alternative, a structure in which the motor axis J and the output axis K, the output axis K and the transmission shaft axis L, and the motor axis J and the transmission shaft axis L are mutually inclined may also be included. The inclination angle of the mutually inclined axes may be, for example, less than 5° or less than 10°.

[0106] The claw rotating mechanism 30 is shown as an example, which rotates the plurality of claws 4 in the clockwise direction when viewed from the front. Alternatively, the plurality of claws 4 may be configured to rotate in the counterclockwise direction when viewed from the front. In this case, the rotation direction of the front shaft 32, in which the one-way clutch 42 transmits power to the drive side gear 43, is counterclockwise when viewed from the front ( Figure 7 In addition, the external thread 33a and the internal thread 32a are provided so that the rear shaft 33 is fastened to the front shaft 32 when the rear shaft 33 rotates in the direction of the second rotation R2.

[0107] The example shows a structure in which an external thread 33a is provided at the front end of the rear axle 33, and an internal thread 32a screwed with the external thread 33a is provided at the rear end of the front axle 32. Alternatively, it can also be configured such that an external thread 32a is provided at the rear end of the front axle 32, and an internal thread 33a screwed with the external thread 32a is provided at the front end of the rear axle 33.

[0108] The feed screw mechanism 25 is exemplified as a ball screw mechanism in which balls 27b are provided between the external thread 27a of the output shaft 27 and the internal thread 26b of the nut 26. Alternatively, for example, a slide screw mechanism may be used in which the external thread 27a and the internal thread 26b are directly screwed together without balls.

[0109] According to the embodiment, both the initial position and the final position of the output shaft 27 (screw shaft) are detected by the Hall IC sensor. Alternatively, only one of the initial position and the final position may be detected by the sensor.

[0110] According to the embodiment, the rotation speed of the motor 20 is detected by the rotation speed detection sensor 20d. It is also possible to configure the initial position and the terminal position of the output shaft 27 to be detected based on the rotation speed of the motor 20 detected by the rotation speed detection sensor 20d instead of the Hall IC sensor. In this case, it is possible to configure the initial position and the terminal position to be detected by the rotation speed detection circuit of the motor 20.

Claims

1. A pipe expansion tool for expanding the end of a synthetic resin fluid pipe, characterized in that: It has a motor shaft, a power conversion mechanism, a plurality of claws and a claw rotation mechanism, wherein: The motor shaft is rotated by the motor; The power conversion mechanism converts the rotation of the motor shaft into forward and backward movement of the output shaft; The plurality of claws are pressed by a wedge disposed at the front portion of the output shaft to open radially outward from each other; The claw rotating mechanism has a transmission shaft that rotates around the axis in conjunction with the rotation of the motor shaft, and the plurality of claws are rotated around the axis by the transmission shaft. The output shaft, the motor shaft, and the transmission shaft of the claw rotating mechanism are arranged in parallel with each other and overlapped in the front-rear direction.

2. The pipe expansion tool according to claim 1, characterized in that: The transmission shaft of the claw rotating mechanism and the electric motor are arranged so that 80% or more of their axial lengths overlap with the output shaft at the rear end position in the front-rear direction.

3. The pipe expansion tool according to claim 2, characterized in that: The transmission shaft and the electric motor of the claw rotating mechanism are arranged so that their respective full axial lengths overlap with the output shaft at the rear end position in the front-rear direction.

4. The pipe expansion tool according to any one of claims 1 to 3, characterized in that: It has a speed change mechanism and an idler wheel, wherein: The speed change mechanism is used to change the speed of the rotation output of the motor shaft; The idler gear is disposed between the speed change mechanism and the power conversion mechanism.

5. The pipe expansion tool according to claim 4, characterized in that: The output shaft and the motor shaft are arranged offset in a vertical direction orthogonal to the front-rear direction. The claw rotating mechanism is located between the output shaft and the motor shaft in the up-down direction when viewed in the axial direction of the output shaft.

6. The pipe expansion tool according to claim 5, characterized in that The claw rotating mechanism is arranged offset with respect to a virtual plane including both the motor shaft and the output shaft.

7. The pipe expansion tool according to any one of claims 1 to 6, characterized in that: The claw rotating mechanism includes a one-way clutch, which rotates in conjunction with a first rotation of the transmission shaft to rotate the plurality of claws, and does not rotate in conjunction with a second rotation opposite to the first rotation of the transmission shaft. The transmission shaft of the claw rotating mechanism has a rear shaft and a front shaft screwed with the front portion of the rear shaft.

8. The pipe expansion tool according to claim 7, characterized in that The front shaft is screwed with respect to the rear shaft so as to be fastened to the rear shaft in the first rotational direction.

9. The pipe expansion tool according to any one of claims 1 to 8, characterized in that: The power conversion mechanism is a feed screw mechanism having an external thread provided on an outer periphery of the output shaft and a nut penetrated by the external thread.

10. The pipe expansion tool according to claim 9, characterized in that A handle is provided, the handle extending in a direction intersecting the axial direction of the output shaft, At least a portion of the nut of the feed screw mechanism and at least a portion of the motor overlap the grip in a front-rear direction.

11. The pipe expansion tool according to claim 1, characterized in that An internal threaded component is provided as the power conversion mechanism, having a screw shaft as the output shaft, The internal thread member rotates forwardly by the forward rotation of the motor and rotates reversely by the reverse rotation of the motor. The screw shaft is screwed together with the internal thread member and moves forward from an initial position to a terminal position by the normal rotation of the internal thread member, and moves backward from the terminal position to the initial position by the reverse rotation of the internal thread member.

12. The pipe expansion tool according to claim 11, characterized in that It has operating components and a controller, wherein: The operating component is used to start the motor; The controller repeatedly rotates the motor forward and reversely during operation of the operating member, thereby opening the plurality of claws a plurality of times.

13. The pipe expansion tool according to claim 12, characterized in that A detection device is provided, and the detection device detects at least one of the initial position and the terminal position of the screw shaft.

14. The pipe expansion tool according to claim 13, characterized in that A detection device is provided, and the detection device detects both the initial position and the terminal position respectively.

15. The pipe expansion tool according to any one of claims 12 to 14, characterized in that: The controller reversely rotates the motor to return the screw shaft to the initial position after the operation of the operating member is released.

16. The pipe expansion tool according to any one of claims 12 to 15, characterized in that: When the screw shaft is not located at the initial position when the operation of the operating member is started, the controller reverses the motor to return the screw shaft to the initial position when the operation of the operating member is started.

17. The pipe expansion tool according to any one of claims 12 to 16, characterized in that: During the operation of the operating component, the controller measures the number of reciprocating movements of the screw shaft between the initial position and the terminal position, and stops the rotation of the motor when the number of reciprocating movements reaches a preset number.

18. The pipe expansion tool according to claim 17, characterized in that The controller calculates the number of reciprocating movements according to the rotation speed of the motor.

19. The pipe expansion tool according to claim 13 or 14, characterized in that: The detection device is a Hall IC sensor.

20. The pipe expansion tool according to claim 13 or 14, characterized in that The detection device is a detection circuit that detects the position of the screw shaft based on the rotation speed of the motor.

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