Pipe expanding tool

Abstract

The invention provides a pipe expanding tool. There is a need for a pipe expanding tool in which a plurality of jaws can expand the diameter of the end of a pipe while suppressing breakage of the end of the pipe. A pipe expanding tool (1) for expanding the diameter of the end of a pipe is provided with a movement mechanism (25) for moving a wedge (3) back and forth. The pipe expanding tool (1) is provided with a plurality of clamping jaws (4) which are pushed by the advancing wedge (3) and mutually expand towards the radial outer direction. The pipe expanding tool (1) has a switch (6a) which, by being operated, transmits a switch-on signal. The pipe expanding tool (1) has a controller. When the controller receives an ON signal from the switch (6a), the wedge (3) is advanced to a first advanced position and the plurality of jaws (4) are opened at a first opening degree. The controller retracts the wedge (3) to close the plurality of jaws. The controller advances the wedge (3) to a second advanced position forward of the first advanced position and opens the plurality of jaws at a second opening greater than the first opening. The controller retracts the wedge to close the plurality of jaws.

Description

Technical Field

[0001] The present invention relates to a pipe expanding tool for expanding the diameter of, for example, an end portion of a pipe so as to connect the end portion to a connected body. Background Art

[0002] In order to connect copper tubes for flowing fluids, for example, a tool for expanding the diameter of the end of one copper tube has been used in the past. The end of the other copper tube that has not been expanded is inserted into the end of the expanded copper tube and brazed. In this way, the copper tubes can be connected to each other. In the past, the tube expansion tool expanded the diameter of the end of the tube manually. The multiple jaws of the tube expansion tool are inserted into the end of the copper tube, and the operating handle is manually operated to move the wedge forward. The multiple jaws arranged in front of the wedge are pushed and opened by the wedge. In this way, the end of the copper tube into which the multiple jaws are inserted is expanded. Depending on the wall thickness of the copper tube, for example, a very strong force is required to expand the diameter of the end of the copper tube.

[0003] Instead of a manual expansion tool, it is considered possible to use an electric expansion tool that uses a motor as a driving source to open a plurality of jaws. Patent document 1 describes an electric expansion tool that expands the diameter of a PEX (cross-linked polyethylene) pipe made of PEX (cross-linked polyethylene). An electric expansion tool for copper pipes is provided based on the electric expansion tool for PEX pipes. By using the motor output to advance a wedge and open a plurality of jaws, the end of the copper pipe can be easily expanded.

[0004] When the end of the elastically deformed PEX pipe is expanded, the plurality of jaws are repeatedly opened and closed to gradually expand the end of the PEX pipe. The plurality of jaws are inserted into the PEX pipe only to a portion of the top end at the beginning of the expansion. The insertion length of the plurality of jaws into the PEX pipe increases as the end of the PEX pipe is expanded. The plurality of jaws rotate circumferentially at a predetermined angle (e.g., every 15°) at each closing action, for example.

[0005] On the other hand, in the case of a copper tube, due to plastic deformation, it is opened at once with a large force, for example. In order to expand the diameter at once, a plurality of jaws are inserted into the copper tube from before the diameter expansion to near the root. When the plurality of jaws start to open, each jaw has not yet received the load from the copper tube. Therefore, the motor rotates at a high speed, and the inertia force of the wedge pushing the plurality of jaws is large. Therefore, when the plurality of jaws start to open, the diameter of the end of the copper tube is expanded with the maximum force. The diameter of the end of the copper tube is expanded at once by using the impulse when the maximum force is applied to the end of the copper tube.

[0006] The plurality of jaws are, for example, divided into six parts along the circumferential direction. When the end of the copper tube is opened at once, each jaw wants to expand the diameter of the end of the copper tube, and the area between the jaws does not act on the end of the copper tube in the direction of expansion. Therefore, the end of the copper tube is expanded into a hexagonal shape. That is, the end of the copper tube has a mixture of expanded parts and almost unexpanded parts, which makes the radial extension uneven. Therefore, cracks sometimes occur at the end of the copper tube. Therefore, it is desired to improve the action of the wedge and the plurality of jaws in the tube expansion tool, for example, for expanding the end of the copper tube. [Prior art literature] [Patent Document]

[0007] Patent Document 1: U.S. Patent No. 20230256498 Summary of the invention [Technical problem to be solved by the invention]

[0008] Therefore, there is a need for a pipe expanding tool that enables a plurality of jaws to expand the diameter of the end portion of the pipe while suppressing damage to the end portion of the pipe. [Technical solutions for solving technical problems]

[0009] According to one feature of the present invention, a pipe expansion tool for expanding the diameter of the end of a pipe has a moving mechanism that moves a wedge forward and backward. The pipe expansion tool has a plurality of jaws that are pushed by the advancing wedge and open radially outward to each other. The pipe expansion tool has a switch that sends an on signal when operated. The pipe expansion tool has a controller. When the controller receives the on signal from the switch, it advances the wedge to a first advanced position and opens the plurality of jaws at a first opening. The controller retreats the wedge and closes the plurality of jaws. The controller advances the wedge to a second advanced position that is forward of the first advanced position and opens the plurality of jaws at a second opening that is larger than the first opening. The controller retreats the wedge and closes the plurality of jaws.

[0010] Therefore, when the switch is turned on, the wedge is first advanced to the first advanced position. The plurality of jaws expand the diameter of the end of the pipe to the first opening. Then, after the plurality of jaws are closed by retreating the wedge, the wedge is advanced to the second advanced position. The plurality of jaws expand the diameter of the end of the pipe to the second opening that is larger than the first opening. In this way, the opening of the plurality of jaws can be changed by changing the advanced position of the wedge. Thus, the diameter of the end of the pipe can be expanded in stages. By expanding the diameter of the end of the pipe in stages, the end of the pipe can be expanded to the target diameter while suppressing the occurrence of cracks or other damage on the end of the pipe during the expansion. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a perspective view of a pipe expansion tool according to the present embodiment when the plurality of jaws are in a closed position. Figure 2 It is a three-dimensional view of the pipe expansion tool when multiple jaws are at the maximum opening. Figure 3 It is a right side view of the tube expansion tool when multiple jaws are at maximum opening. 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 housing removed, as viewed from the rear right side. Figure 6 This is a perspective view of the tool body with the housing removed, when the screw shaft is in the initial position, as viewed from the left rear side. Figure 7 It is a left side view of the tool body with the housing removed and the screw shaft in the initial position. Figure 8 The left side view of the tool body with the housing removed and the screw shaft in the end position. Fig. 9 This is a longitudinal sectional view of the tool body when the wedge and the screw shaft are in the initial position as viewed from the right. Fig.10 This is a longitudinal sectional view of the tool body when the wedge and the screw shaft are in the terminal position as viewed from the right. Fig.11 yes Fig. 9 The XI-XI section view in FIG. Fig.12 yes Fig.11 The XII-XII section view in FIG. Fig.13 yes Fig.11 In section XII-XII in FIG. 1 , a sectional view of the wedge and the screw shaft is shown when they are in the terminal position. Fig.14 It is a top view of the rotating gear, the bearing cam and the multiple clamping jaws. Fig.15 is a block diagram showing the electronic components of the tube expansion tool. Fig.16 This is a flowchart showing a first example of the operation of the wedge and the plurality of grippers. Fig.17 This is a flowchart showing a second example of the operation of the wedge and the plurality of grippers. Fig.18 This is a flowchart showing a third example of the operation of the wedge and the plurality of grippers. [Explanation of Reference Numerals] 1: expansion tool; 2: end cap; 2a: jaw support groove; 2b: internal thread; 3: wedge; 4: jaw; 4a: ring receiving groove; 4b: jaw engaging portion; 4c: ring; 4d: convex portion; 5: grip; 6: trigger; 6a: switch; 7: protrusion; 7a: battery mounting portion; 8: battery; 9: controller; 10: tool body; 11: body housing; 12: front mechanism housing; 12a: external thread; 12b: first inner peripheral surface; 12c: second inner peripheral surface; 12d: radial extension surface; 13: first central mechanism housing; 13a: inner peripheral surface; 13b: lower extension portion; 13c: recess; 13d: through hole; 13e: shaft support portion; 14: second central mechanism housing; 14a: inner peripheral surface; 1 4b: lower extension; 14c: recess; 14d: through hole; 14e: guide shaft support; 14f: spring receiving portion; 14g: shaft support; 15: rear mechanism housing; 15a: through hole; 16: bolt; 17: housing; 18: input portion; 20: motor; 20a: motor shaft; 20b: stator; 20c: rotor; 20d: speed detection sensor; 20e, 20f: bearing; 21: fan; 22: planetary reduction mechanism; 23: gear shaft; 23a: driving side gear; 23b, 23c: bearing; 24: idler; 24a: shaft component; 24b: radial bearing; 25: moving mechanism (ball screw mechanism); 26: internal thread component; 26a: driven side gear; 26b: Internal thread; 26c, 26d: bearing; 26e: thrust bearing; 27: screw shaft; 27a: external thread; 27b: ball; 28: screw shaft guide; 28a: roller shaft; 28b: roller; 28c: guide rail; 28d, 28e: magnet; 29: position sensor; 29a: initial position sensor; 29b: terminal position sensor; 30: rotating mechanism; 31: shaft; 32: front shaft; 32a: Internal thread; 33: rear axle; 33a: external thread; 33b: ball groove; 34: push plate; 34a: through hole; 35: ball holder; 35a: sleeve mounting portion; 35b: ball holding hole; 35c: shaft insertion hole; 35d: lateral extension; 35e: through hole; 36: sleeve; 37: nut; 38: ball; 39: compression spring; 41: guide shaft; 42: one-way clutch; 43: driving side gear; 50: rotating gear; 50a: driven side gear; 50b: cylinder wall; 50c: Through hole; 50d: spring bearing portion; 50e: guide; 51: bearing cam; 51a: cylindrical portion; 51b: through hole; 51c: spring bearing portion; 51d: guide engaging portion; 51e: cam engaging portion; 51f: front surface; 52: coil spring; 60: tube; 60a: inner circumference; 60b: end; J: motor axis; K: screw shaft axis; R1: first rotation; R2: second rotation; P1: initial position; P2: terminal position; D1: closed diameter; D2: maximum opening diameter. DETAILED DESCRIPTION

[0012] According to another feature of the present invention, the pipe expansion tool has a rotating mechanism, which rotates the plurality of jaws around the axis of the wedge in conjunction with the retreat of the wedge. Therefore, the plurality of jaws change their positions around the axis of the wedge each time they are closed. Therefore, each jaw changes the position of the inner circumferential surface of the end of the pipe around the axis of the wedge during each expansion operation. Therefore, by performing multiple expansion operations, the opening shape of the end of the expanded pipe can be made close to a perfect circle. As a result, the end of the pipe can be expanded evenly, and the occurrence of cracks and other damage at the end of the pipe can be suppressed.

[0013] According to another feature of the present invention, the controller advances the wedge from the initial position to the first advanced position. The controller retreats the wedge from the first advanced position to the initial position. The controller advances the wedge from the initial position to the second advanced position. The controller retreats the wedge from the second advanced position to the initial position. Therefore, each time the wedge is retreated to the initial position, the plurality of jaws are reliably closed to the closed position. Therefore, the plurality of jaws are prevented from contacting the end of the pipe when the plurality of jaws are closed while rotating around the axis of the wedge. Thus, the plurality of jaws can be prevented from biting the end of the pipe, and the plurality of jaws can be opened and closed smoothly.

[0014] According to another feature of the present invention, the controller advances the wedge from the initial position to the second advanced position. The controller retreats the wedge from the second advanced position to the first retreated position that is forward of the initial position. The controller advances the wedge from the first retreated position to a position forward of the second advanced position. Therefore, by setting the first retreated position forward of the initial position, the total movement amount of the wedge can be suppressed. Thus, the end of the pipe can be rapidly expanded in diameter.

[0015] According to another feature of the present invention, the controller moves the wedge forward and backward multiple times while receiving the on signal from the switch, and each time the wedge moves forward, the wedge approaches the terminal position. After the wedge reaches the terminal position, the controller returns the wedge and stops it at the initial position. Therefore, when the wedge reaches the terminal position, the plurality of clamps expand the diameter of the end of the pipe to the maximum opening. By returning the wedge and stopping it at the initial position after the expansion of the end of the pipe is completed, it is possible to quickly shift to a state of preparation for expanding the diameter of the end of the next pipe. As a result, the operation time for expanding the diameters of the ends of the plurality of pipes can be shortened, thereby improving the workability.

[0016] According to another feature of the present invention, the controller moves the wedge forward and backward multiple times while receiving the on signal from the switch, and each time the wedge is advanced, the wedge approaches the terminal position. After the wedge reaches the terminal position, the controller moves the wedge backward. The controller advances the wedge to the terminal position again. Therefore, when the wedge reaches the terminal position, the plurality of clamps expand the diameter of the end of the pipe to the maximum opening. By repeatedly performing the operation of opening the plurality of clamps to the maximum opening and then closing them, the opening shape of the end of the pipe opened to the maximum opening can be made closer to a perfect circle.

[0017] According to another feature of the present invention, the pipe expansion tool has an input part, which inputs the number of forward and backward movements of the wedge. The input part sends a signal of the number of times information to the controller. Therefore, the number of forward and backward movements of the wedge can be changed according to, for example, the diameter, wall thickness, or material of the pipe. As a result, it is possible to effectively suppress the generation of cracks at the end of the pipe during the expansion.

[0018] According to another feature of the present invention, the controller calculates the first and second advanced positions based on the number of times information. Therefore, the controller can calculate the first and second advanced positions to efficiently move the wedge, thereby improving the work efficiency.

[0019] According to another feature of the present invention, the pipe expansion tool has an initial position sensor that detects the initial position of the wedge and sends a signal to the controller. The pipe expansion tool has a terminal position sensor that detects the terminal position of the wedge and sends a signal to the controller. The pipe expansion tool has a motor that drives the moving mechanism. The pipe expansion tool has a rotation speed detection sensor that detects the rotation speed of the motor. The controller calculates the position of the wedge based on the signal from the rotation speed detection sensor. Therefore, the position of the wedge relative to the initial position or the terminal position can be quickly detected by detecting the rotation speed of the motor. Therefore, the movement of the wedge and the opening and closing of the plurality of jaws can be smoothly operated.

[0020] According to another feature of the present invention, the moving mechanism has a screw shaft, which is arranged on the wedge. The moving mechanism has an internal threaded component, which moves the screw shaft forward and backward by being screwed with the screw shaft and rotating around the axis of the screw shaft. Therefore, in a pipe expansion tool that converts the rotation of the internal threaded component into the forward and backward movement of the screw shaft and the wedge, it is also possible to move the wedge to multiple forward positions and open multiple jaws with different openings. In this way, the end of the pipe can be expanded while suppressing the occurrence of damage such as cracks.

[0021] Next, according to Figures 1 to 18 To illustrate an embodiment of the present invention. 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 The handle 5 is held at the left side of the hand (the deep side in the left direction). In the following description, the near side of the user is set as the rear, and the side opposite to the near side of the user is set as the front. The up, down, left and right directions are based on the user.

[0022] like Figure 1 , 9 As shown in Figure 10, an annular end cap 2 is installed at the front part of the tool body 10. A cylindrical screw 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 screw shaft 27. The wedge 3 is located radially inward of the end cap 2. The screw shaft 27 and the wedge 3 are arranged on the screw shaft axis K which is located in the center of the tool body 10 and extends in the front-to-back direction. The wedge 3 can move in the front-to-back direction along the screw shaft axis K integrally with the screw shaft 27. The wedge 3 can move in the front-to-back direction within a range with the initial position P1 as the rear end and the terminal position P2 as the front end.

[0023] like Figure 2 , 3As shown in Figures 9 and 10, a plurality of jaws 4 extending in the front-to-back direction are provided radially outward of the wedge 3 and radially inward of the end cap 2. The plurality of jaws 4 are arranged at equal intervals along the circumference of the wedge 3. The pipe expansion tool 1 has, for example, 6 jaws 4, each of which is arranged at 60° intervals along the circumference of the wedge 3. The plurality of jaws 4 are inserted into the end 60b of the cylindrical tube 60. The tube 60 is made of, for example, copper, and is provided with a substantially constant diameter and a substantially constant wall thickness along the length direction. The plurality of jaws 4 can be opened and closed radially between a closed position in which the wedge 3 is tightly covered in the circumferential direction and a maximum opening in which the top of the wedge 3 is exposed by opening radially outward. The outer circumferential surfaces of the plurality of jaws 4 are cylindrical with a closed diameter D1 in the closed position. The closed diameter D1 is slightly smaller than the diameter of the inner circumferential surface 60a of the tube 60 that has not been expanded. The outer circumferential surfaces of the plurality of jaws 4 are cylindrical with a maximum opening diameter D2 at the maximum opening. The outer peripheral surface of each clamping jaw 4 extends substantially straight with respect to the front-rear direction and is hardly inclined in both the closed position and the maximum opening.

[0024] like Figure 3 As shown, the maximum opening diameter D2 is the diameter of the inner peripheral surface 60a when the end 60b of the tube 60 is expanded, for example, slightly larger than the outer diameter of the end 60b of the other tube 60. The end 60b of the other tube 60 is inserted and brazed into the end 60b of the expanded tube 60. Thus, the ends 60b of the two tubes 60 are connected.

[0025] like Figure 1 , 2 As shown, a trigger-type trigger 6 is provided on the front surface of the handle 5. The user can pull the trigger 6 while holding the handle 5. A switch 6a is provided inside the handle 5, and the switch 6a switches on and off in a manner linked to the operation of the trigger 6. When the trigger 6 is not pulled, the switch 6a is in an off state, and when the trigger 6 is pulled, the switch 6a is in an on state. When the switch 6a is in the on state, it sends an on signal to the controller 9 described later. When the switch 6a is in the off state, it stops sending the on signal to the controller 9. When using the pipe expansion tool 1, the user holds the handle 5 to insert the plurality of jaws 4 into the end 60b of the pipe 60 (refer to Figure 3 ). The plurality of jaws 4 are opened and closed in the radial direction by pulling the trigger 6. Finally, the inner peripheral surface 60a of the end portion 60b of the tube 60 is expanded to the maximum opening diameter D2.

[0026] like Figure 1 , 2As shown in Figures 1 and 11, a roughly rectangular box-shaped protrusion 7 is provided at the lower end of the handle 5, which is extended in the front-rear direction and the left-right direction than the handle 5. A controller 9 is accommodated in the protrusion 7. The controller 9 has a shallow-bottomed rectangular box-shaped housing and a control substrate that is accommodated in the housing and is made of resin mold. The controller 9 is accommodated in the protrusion 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. An input unit 18 is provided on the upper surface of the protrusion 7. The input unit 18 includes, for example, an operating unit that can be pressed and a display unit that changes the display by operating the operating unit. The signal input by the input unit 18 is sent to the controller 9.

[0027] like Figure 1 , 2 As shown in FIGS. 1 and 11 , a battery mounting portion 7a is provided on the lower surface of the protrusion 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 using a separately prepared charger. The battery 8 can be used as a power source for other electric tools. The battery 8 functions as a power source for supplying electric power to the motor 20 and the like.

[0028] like Fig. 9 , 10 As shown, the main body housing 11 includes a housing 17 covering the outer periphery of the tool body 10 and a front mechanism housing 12, a first central mechanism housing 13, a second central mechanism housing 14, and a rear mechanism housing 15 connected to each other in the housing 17. 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 to be a plate 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 are connected in the front-to-back direction by bolts 16, and form a mechanism housing by working together. In the mechanism housing, a gear shaft 23, an idler gear 24, and an internal thread component 26 described later are accommodated.

[0029] like Figure 4 , 9 As shown in FIG. 10 , 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 cap 2. The end cap 2 is connected to the front part of the front mechanism housing 12 by screwing the external thread 12a with the internal thread 2b.

[0030] like Figure 4 , 9As shown in Figures 10 and 11, the first central mechanism housing 13 has a generally U-shaped downward extension portion 13b extending downward from the cylindrical shape. The second central mechanism housing 14 has a generally U-shaped downward extension portion 14b extending downward from the cylindrical shape. The downward extension portion 13b and the downward extension 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 described later. The downward extension portion 13b is provided with two through holes extending in the front-to-back direction in parallel from top to bottom. A recessed portion 13c is provided in the through hole on the lower side, and the recessed portion 13c is used to press-fit the bearing 23b supporting the gear shaft 23. The shaft member 24a supporting the idler gear 24 is pressed into the through hole 13d on the upper side. The downward extension portion 14b is provided with two through holes extending in the front-to-back direction in parallel from top to bottom. A recessed portion 14c is provided in the through hole on the lower side, and the recessed portion 14c is used to press-fit the bearing 23c supporting the gear shaft 23. The shaft member 24a is inserted into the upper through hole 14d.

[0031] like Fig. 9 , 10 As shown, a roughly cylindrical motor 20 is housed in the rear lower portion of the housing 17. The motor 20 uses a motor called a DC brushless motor, for example. The motor 20 is located below the screw shaft 27 and above the handle 5. The motor shaft 20a of the motor 20 extends in the front-to-back direction along the motor axis J in a manner parallel to the screw shaft axis K passing through the center of the screw shaft 27. The motor shaft 20a is supported by bearings 20e and 20f held in the housing 17 so as to be rotatable around the motor axis J.

[0032] like Fig. 9 , 10 As shown, the motor 20 has a stator 20b, which is supported by the housing 17 in a non-rotatable manner. The stator 20b is arranged radially outward 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 can rotate integrally 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, a fan 21 that can rotate integrally with the motor shaft 20a is provided between the rotor 20c and the rear bearing 20f. When the fan 21 rotates together with the motor shaft 20a, cooling air flows from the front to the rear of the motor 20 to cool the motor 20.

[0033] like Fig. 9 , 10As shown, a planetary reduction mechanism 22 is provided in front of the motor 20, and the planetary reduction mechanism 22 is used to reduce the output of the motor shaft 20a. The planetary reduction mechanism 22 and the motor 20 are arranged in the front-to-back direction and are accommodated in the housing 17. The rotational drive of the motor shaft 20a is reduced in two stages in the planetary reduction mechanism 22 and transmitted to the gear shaft 23. The gear shaft 23 is supported by bearings 23b and 23c so as to be rotatable around the motor axis J. The gear shaft 23 has a driving side gear 23a between the bearing 23b and the bearing 23c in the front-to-back direction. The driving side gear 23a rotates integrally with the gear shaft 23 around the motor axis J.

[0034] like Fig. 9 , 10 As shown, an idler wheel 24 is provided between the gear shaft 23 and the screw shaft 27 in the vertical direction. The idler wheel 24 is supported to be rotatable around the axis of a cylindrical shaft member 24a extending in the front-rear direction. A radial bearing 24b is provided between the idler wheel 24 and the shaft member 24a in the radial direction. The idler wheel 24 meshes with the driving side gear 23a below and meshes with the driven side gear 26a of the internal thread member 26 above.

[0035] like Fig. 9 , 10 As shown, a moving mechanism 25 of a feed screw mechanism called a so-called ball screw mechanism is provided on the tool body 10. The moving mechanism 25 has a screw shaft 27 and an internal thread component 26. An external thread 27a is provided on the outer peripheral surface of the screw shaft 27. The internal thread component 26 is provided in a substantially cylindrical shape covering the screw shaft 27 in the circumferential direction. An internal thread 26b is provided on the inner peripheral surface of the internal thread component 26. The internal thread 26b is screwed with the external thread 27a of the screw shaft 27 via a plurality of balls 27b. A driven side gear 26a protruding radially outward is provided on the outer periphery of the internal thread component 26. The rotational drive of the gear shaft 23 is transmitted to the internal thread component 26 at a reduced speed through the meshing of the driving side gear 23a with the idler gear 24 and the meshing of the idler gear 24 with the driven side gear 26a.

[0036] like Fig. 9 , 10 As shown, the internal thread component 26 is supported by bearings 26c and 26d housed in the tool body 10 so as to be rotatable about the screw shaft 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 internal thread component 26 and the front surface of the rear side mechanism housing 15, and the thrust bearing 26e is used to bear the thrust load of pushing the internal thread component 26 backward. The rear portion of the screw shaft 27 can protrude backward from the through hole 15a provided in the center of the rear side mechanism housing 15.

[0037] like Figures 4 to 6 As shown, a screw shaft guide 28 is installed at the rear of the screw shaft 27, and the screw shaft guide 28 stops the rear of the screw shaft 27 and guides the front-rear movement of the screw shaft 27. The screw shaft guide 28 has a roller shaft 28a, which is connected to the rear end of the screw shaft 27 and extends in the left-right direction. Rollers 28b are provided at the left and right ends of the roller shaft 28a. A pair of annular guide rails 28c extending in the front-rear direction are respectively installed on the left and right side parts of the second central mechanism housing 14. The roller 28b can engage with the guide rail 28c and move in the front-rear direction along the guide rail 28c. The screw shaft 27 can be guided by the roller 28b and the guide rail 28c and move in the front-rear direction together with the screw shaft guide 28.

[0038] like Figures 7-10 As shown, magnets 28d and 28e are provided on the upper part of the roller shaft 28a. The magnet 28d on the rear side and the magnet 28e on the front side are spaced apart from each other along the front and rear. A position sensor 29 for detecting the front and rear positions of the screw shaft 27 is provided on the upper inner peripheral surface of the housing 17. The position sensor 29 is a sensor for detecting magnetic fields, which is called a Hall IC. The position sensor 29 includes an initial position sensor 29a on the rear side and a terminal position sensor 29b on the front side. The initial position sensor 29a is configured to be located directly above the magnet 28d when the wedge 3 and the screw shaft 27 are in the initial position P1. The initial position sensor 29a detects the initial position P1 of the wedge 3 when the magnet 28d moves directly downward, and sends a signal to the controller 9 (refer to Figure 1 The terminal position sensor 29b is configured to be located directly above the magnet 28e when the wedge 3 and the screw shaft 27 are at the terminal position P2. The terminal position sensor 29b detects the terminal position P2 of the wedge 3 when the magnet 28e moves directly downward, and sends a signal to the controller 9.

[0039] like Figures 6 to 8 As shown in FIGS. 12 and 13, the tool body 10 has a rotating mechanism 30 for rotating the plurality of jaws 4. The plurality of jaws 4 are rotated around the screw shaft axis K by the rotating mechanism 30. The rotating mechanism 30 has a push plate 34 and a shaft 31, wherein the push plate 34 moves forward and backward in conjunction with the rotation of the motor shaft 20a; and the shaft 31 rotates around the axis in conjunction with the forward and backward movement of the push plate 34.

[0040] like Figure 5 , 7As shown in Figures 1 and 8, the rotating mechanism 30 has a ball holder 35 mounted on the shaft 31. The ball holder 35 can move in the front-to-back direction along the extension direction of the shaft 31. A guide shaft 41 extending parallel to the shaft 31 is provided on the right side of the shaft 31. A cylindrical guide shaft support portion 14e protruding rearward is provided on the lower extension portion 14b of the second central mechanism housing 14. An internal thread penetrating in the front-to-back direction is provided at the center of the guide shaft support portion 14e. The guide shaft 41 is fixed to the second central mechanism housing 14 by screwing the external thread provided at the top end into the internal thread of the guide shaft support portion 14e.

[0041] like Figure 4 , 5 As shown, the ball retainer 35 has a sleeve mounting portion 35a that is roughly cylindrical and a lateral extension portion 35d that extends to the right of the sleeve mounting portion 35a. An axis insertion hole 35c that penetrates in the front-to-back direction is provided in the center of the sleeve mounting portion 35a. The shaft 31 is inserted into the axis insertion hole 35c in a manner that allows it to slide in the front-to-back direction. A through hole 35e that penetrates in the front-to-back direction is provided in the lateral extension portion 35d. A guide shaft 41 is inserted into the through hole 35e in a manner that allows it to slide in the front-to-back direction. Thus, the ball retainer 35 can be guided by the shaft 31 and the guide shaft 41 to slide in the front-to-back direction, and the rotation around the axis of the shaft 31 is restricted.

[0042] like Figures 4 to 6 As shown, the plate-shaped push plate 34 is integrally mounted on the roller shaft 28a in a posture with the plate thickness direction being the front-to-back direction. The push plate 34 extends downward from the roller shaft 28a and is arranged behind the sleeve mounting portion 35a. The push plate 34 has a through hole 34a that penetrates in the front-to-back direction. In the through hole 34a, the shaft 31 protruding backward from the sleeve mounting portion 35a is inserted. The push plate 34 moves forward and backward in an integrated manner with the screw shaft 27. When the screw shaft 27 moves forward, the push plate 34 pushes the rear surface of the ball retainer 35 forward. When the screw shaft 27 moves backward, the push plate 34 moves in a manner away from the ball retainer 35. Therefore, the push plate 34 applies force to the ball retainer 35 only when moving forward.

[0043] like Figure 4As shown, a pair of ball retaining holes 35b are provided on the sleeve mounting portion 35a, and the pair of ball retaining holes 35b extend radially in a manner connected to the shaft insertion hole 35c. Balls 38 are respectively inserted into the pair of ball retaining holes 35b. A sleeve 36 is installed on the sleeve mounting portion 35a, and the sleeve 36 covers the pair of balls 38 and the ball retaining holes 35b from the radial outside. By installing the sleeve 36 on the sleeve mounting portion 35a, the pair of balls 38 are retained in a manner that does not disengage from the ball retaining holes 35b. The pair of balls 38 are arranged at positions facing each other at 180° around the axis of the shaft 31. The movement of the pair of balls 38 around the axis of the shaft 31 is limited by the ball retainer 35 being stopped. A nut 37 for retaining the sleeve 36 is installed at the front of the sleeve mounting portion 35a.

[0044] like Figure 4 , 12 As shown in Figures 1 and 13, the shaft 31 is formed by assembling a front shaft 32 and a rear shaft 33 in the front-to-back direction. The front shaft 32 is supported by the shaft support portion 13e of the first central mechanism housing 13 in a manner that allows rotation around the axis. The rear shaft 33 is supported by the shaft support portion 14g of the second central mechanism housing 14 in a manner that allows rotation around the axis. The rear shaft 33 is inserted into the ball retainer 35. An external thread 33a is provided at the front portion of the rear shaft 33. An internal thread 32a that is screwed with the external thread 33a is provided at the rear portion of the front shaft 32. By screwing the internal thread 32a with the external thread 33a, the front shaft 32 and the rear shaft 33 are mounted integrally with each other.

[0045] like Figure 4 , 12 As shown in FIG. 13 , a pair of ball grooves 33b are provided on the outer peripheral surface of the rear shaft 33. The ball grooves 33b extend substantially along the longitudinal direction of the rear shaft 33 and extend circumferentially from the rear to the front in the manner of a thread groove. The ball grooves 33b extend from the rear to the front in the manner of a second rotation R2 (refer to FIG. Figure 6 ) 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. In each ball groove 33b, a ball 38 protruding radially inward from the ball retaining hole 35b of the ball retainer 35 to the shaft insertion hole 35c is engaged.

[0046] like Figures 6 to 8 As shown, when the ball holder 35 moves forward and backward relative to the rear axle 33, a pair of balls 38 (see Figure 4) moves in the ball groove 33b along the extension direction of the ball groove 33b. Since the pair of balls 38 will not move around the axis of the rear axle 33, the rear axle 33 rotates around the axis relative to the ball retainer 35 that moves forward and backward. When the ball retainer 35 moves forward, the rear axle 33 rotates in the direction of the first rotation R1 relative to the ball retainer 35. When the ball retainer 35 moves backward, the rear axle 33 rotates in the direction of the second rotation R2 relative to the ball retainer 35. The front axle 32 screwed to the rear axle 33 rotates around the axis integrally with the rear axle 33. A flange-shaped spring bearing portion 14f extending radially is provided on the shaft support portion 14g of the second central mechanism housing 14. Between the spring bearing portion 14f and the front-to-back direction of the ball retainer 35, a compression spring 39 that applies force to the ball retainer 35 toward the rear is sandwiched.

[0047] like Figures 11 to 13 As shown in FIG. 1 , the rotating 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 mounted on the front part of the front shaft 32 in front of the 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 transmits only the rotation in one direction of the radial inner peripheral surface side to the radial outer peripheral surface side through a structure such as a so-called sprag type. The one-way clutch 42 transmits the second rotation R2 (refer to FIG. 1 ) of the front shaft 32 to the Figure 6 ) is transmitted to the driving side gear 43. The one-way clutch 42 does not transmit the first rotation R1 (refer to Figure 6 ) is transmitted to the driving side gear 43 to cause the front axle 32 to idle.

[0048] like Figure 4 , 12 As shown in Figures 1 and 13, the rotating mechanism 30 has a rotating gear 50 having a substantially cylindrical shape and a receiving cam 51 having a substantially cylindrical shape. The rotating gear 50 is arranged in front of the internal thread component 26. The receiving cam 51 is arranged in front of the rotating gear 50. The front mechanism housing 12 has a first inner peripheral surface 12b and a second inner peripheral surface 12c as the inner peripheral surface of the cylinder centered on the screw shaft axis K. The rotating gear 50 is supported by the first inner peripheral surface 12b of the front mechanism housing 12 so as to be rotatable around the screw shaft axis K. The receiving cam 51 is supported by the second inner peripheral surface 12c of the front mechanism housing 12 so as to be rotatable around the screw shaft axis K. The front end of the first inner peripheral surface 12b and the rear end of the second inner peripheral surface 12c are connected by a radial extension surface 12d extending radially.

[0049] like Figure 4 , 12As shown in 13, the rotating gear 50 has a cylindrical wall 50b and a driven side gear 50a protruding radially from the rear of the cylindrical wall 50b. A through hole 50c penetrating in the front-to-back direction is provided in the center of the cylindrical wall 50b. The through hole 50c is provided with a diameter that enables the wedge 3 and the screw shaft 27 to be inserted therein and move in the front-to-back direction. The driven side gear 50a meshes with the driving side gear 43. The rotational power of the driving side gear 43 is decelerated and transmitted to the driven side gear 50a. The driven side gear 50a rotates to the second rotation R2 (refer to Figure 6 ) direction, it rotates counterclockwise when viewed from the front. The driven side gear 50a rotates in the first rotation R1 (refer to Figure 6 ), it rotates in the clockwise direction when viewed from the front. The rotating gear 50 has a spring receiving portion 50d extending radially inward from the rear portion of the cylindrical wall 50b. The inner peripheral surface of the spring receiving portion 50d is set to a diameter that allows the screw shaft 27 to be inserted therein and does not allow the rear end 3a of the wedge 3 to pass therethrough. The rear portion of the coil spring 52 described later abuts against the front surface of the spring receiving portion 50d.

[0050] like Figure 4 , 14 As shown, the rotating gear 50 has a substantially rectangular guide 50e protruding forward from the front surface of the cylindrical wall 50b. Two guides 50e are provided at intervals of 180° along the circumferential direction of the cylindrical wall 50b. The guides 50e guide the receiving cam 51 so that it can move in the front-rear direction without causing the receiving cam 51 to rotate relative to the rotating gear 50.

[0051] like Figure 4 , 12 As shown in Figures 1 to 14, the receiving cam 51 has a cylindrical portion 51a in a cylindrical shape. A through hole 51b is provided in the center of the cylindrical portion 51a and penetrates in the front-rear direction. The through hole 51b is provided with a diameter capable of inserting the wedge 3 and the screw shaft 27. A spring receiving portion 51c protruding radially outward in a flange shape is provided at the rear of the cylindrical portion 51a. A coil spring 52 is interposed between the spring receiving portion 50d of the rotating gear 50 and the spring receiving portion 51c of the receiving cam 51. The receiving cam 51 is urged forward relative to the rotating gear 50 by the coil spring 52.

[0052] like Figure 4 , 14As shown in FIG. 1 , a guide engaging portion 51d is provided on the spring receiving portion 51c, which is notched radially inward and penetrates the spring receiving portion 51c in the front-rear direction. Two guide engaging portions 51d are provided at intervals of 180° along the circumference of the spring receiving portion 51c. Each guide engaging portion 51d engages with each guide member 50e of the rotating gear 50. As a result, the receiving cam 51 and the rotating gear 50 are integrally connected around the screw shaft axis K (refer to FIG. 1 ). Fig.12 ) axis. In addition, the receiving cam 51 can move relative to the rotating gear 50 in the front-rear direction.

[0053] like Figure 4 , 14 As shown, the bearing cam 51 has a plurality of cam engaging portions 51e protruding forward from the front surface 51f of the cylindrical portion 51a. Each cam engaging portion 51e is formed into a roughly rectangular shape. A total of 6 cam engaging portions 51e are provided at 60° intervals along the circumference of the cylindrical portion 51a. A concave jaw engaging portion 4b engaging with any one of the plurality of cam engaging portions 51e is provided on the rear surface of the jaw 4. The plurality of jaws 4 rotate integrally with the bearing cam 51 around the screw shaft axis K by engaging each cam engaging portion 51e with the jaw engaging portion 4b of each jaw 4. A convex portion 4d convexly shaped to the rear relative to the jaw engaging portion 4b is formed at both ends in the circumferential direction of each jaw engaging portion 4b.

[0054] like Fig. 9 , 10 As shown, a ring receiving groove 4a with an arc-shaped cross section is provided on the radial outer periphery of the rear part of each jaw 4. The ring receiving grooves 4a of multiple jaws 4 are connected in the circumferential direction to form an annular groove. Multiple jaws 4 are connected in the circumferential direction by a ring 4c that is inserted into the ring receiving groove 4a and can elastically expand and contract. A jaw supporting groove 2a that can accommodate the ring 4c is provided on the inner circumferential surface of the end cap 2 in a manner extending radially outward and circumferentially. The jaw supporting groove 2a allows the ring 4c to move in the radial direction, but limits the movement of the ring 4c in the front-rear direction. Multiple jaws 4 open and close radially with the ring 4c supported by the jaw supporting groove 2a as the center.

[0055] Reference Figures 6 to 13The driving of the moving mechanism 25 and the rotating mechanism 30 will be described below. First, the motor shaft 20a of the motor 20 rotates. The motor 20 is switched between forward and reverse rotation by the controller 9. The rotational drive of the motor shaft 20a is decelerated by the planetary reduction mechanism 22 and transmitted to the gear shaft 23. When the gear shaft 23 rotates, the idler gear 24 meshing with the driving side gear 23a rotates. The internal thread component 26 meshing with the idler gear 24 at the driven side gear 26a rotates around the screw shaft axis K. When the internal thread component 26 rotates, the screw shaft 27 stopped by the screw shaft guide 28 moves forward and backward. The screw shaft 27 moves forward when the motor 20 rotates forward, and moves backward when the motor 20 rotates reversely. When the screw shaft 27 moves forward, the wedge 3 also moves forward and pushes the plurality of jaws 4 and the ring 4c in a manner that opens radially outward. When the screw shaft 27 moves backward, the wedge 3 also moves backward and the pushing force is eliminated. Therefore, the ring 4c contracts and the plurality of jaws 4 close radially inward.

[0056] When the screw shaft 27 moves forward, the push plate 34 mounted on the roller shaft 28a also moves forward integrally. The push plate 34 pushes the ball retainer 35 forward by overcoming the force of the compression spring 39. When the ball retainer 35 moves forward, the shaft 31 rotates in the direction of the first rotation R1. At this time, the one-way clutch 42 does not transmit the rotational power of the shaft 31 to the drive side gear 43. The rotating gear 50 does not rotate because the rotational power is not transmitted from the drive side gear 43. Therefore, the bearing cam 51 and the multiple jaws 4 connected to the rotating gear 50 do not rotate. As a result, the multiple jaws 4 do not rotate around the screw shaft axis K, but are pushed radially outward by the wedge 3 to open.

[0057] When the screw shaft 27 retreats, the push plate 34 installed on the roller shaft 28a also retreats integrally. The ball retainer 35 is released due to the pushing force of the push plate 34, and is forced to move backward by the compression spring 39. When the ball retainer 35 retreats, the shaft 31 rotates in the direction of the second rotation R2. At this time, the one-way clutch 42 transmits the rotational power of the front shaft 32 to the drive side gear 43. The rotating gear 50 rotates in the counterclockwise direction as viewed from the front by the rotational power transmitted from the drive side gear 43. The bearing cam 51 and the multiple jaws 4 also rotate integrally with the rotating gear 50. As a result, the multiple jaws 4 rotate in the counterclockwise direction as viewed from the front around the screw shaft axis K while closing radially inward.

[0058] Next, various examples of the operation of the wedge 3 and the plurality of jaws 4 in the present invention are shown. The position of the wedge 3 movement or the number of times it moves in the front-rear direction, the opening degree of the plurality of jaws 4 or the number of times they are opened and closed are not limited to the examples.

[0059] like Fig.15As shown, the controller 9 receives the ON signal of the switch 6a and drives the motor 20. The controller 9 supplies electric power from the battery 8 to the motor 20 to drive the motor 20. The controller 9 detects that the wedge 3 is located at the initial position P1 (see FIG. 1 ) based on the signal sent from the initial position sensor 29a. Fig. 9 The controller 9 detects that the wedge 3 is located at the terminal position P2 (see Fig.10 ). The controller 9 calculates the moving distance of the wedge 3 from the initial position P1 or the terminal position P2 from the rotation speed of the motor 20 based on the signal sent from the rotation speed detection sensor 20d. Thus, the position of the wedge 3 between the initial position P1 and the terminal position P2 is calculated. The controller 9 calculates the movement of the wedge 3 based on the signal sent from the input unit 18. For example, the input unit 18 can input the number of times the wedge 3 is moved forward and backward. A signal of the number of times information is sent from the input unit 18 to the controller 9.

[0060] according to Fig. 9 , 10 , 15, and 16 show a first example of the action of the wedge 3 and the plurality of jaws 4. First, the user pulls the trigger 6 (step 01, hereinafter referred to as ST01). While the trigger 6 is pulled, the switch 6a sends an on signal to the controller 9 (ST02). The controller 9 drives the motor 20 in the forward direction (ST03). The wedge 3 advances 4 mm from the initial position P1 to the first advanced position further rearward than the terminal position P2 through the moving mechanism 25. The plurality of jaws 4 are pushed by the wedge 3 and open to the first opening whose diameter is larger than the closed diameter D1 (ST04). The controller 9 reverses the motor 20. The wedge 3 retreats 4 mm from the first advanced position to the initial position P1 through the moving mechanism 25. The plurality of jaws 4 close from the first opening to the closed position and rotate around the screw shaft axis K through the rotating mechanism 30 (ST05). The plurality of jaws 4 rotate, for example, 15° counterclockwise when viewed from the front.

[0061] The controller 9 rotates the motor 20 forward. The wedge 3 advances 8 mm from the initial position P1 to the second advanced position which is forward of the first advanced position and rearward of the terminal position P2 through the moving mechanism 25. The plurality of jaws 4 are pushed by the wedge 3 and open to the second opening which is larger in diameter than the first opening (ST06). The controller 9 reverses the motor 20. The wedge 3 retreats 8 mm from the second advanced position to the initial position P1 through the moving mechanism 25. The plurality of jaws 4 close from the second opening to the closed position and rotate around the screw shaft axis K through the rotating mechanism 30 (ST07). The plurality of jaws 4 rotate, for example, 30° counterclockwise when viewed from the front. When the wedge 3 retreats once, the angle of rotation of the plurality of jaws 4 is roughly proportional to the distance the wedge 3 retreats.

[0062] The controller 9 rotates the motor 20 forward. The wedge 3 advances 12 mm from the initial position P1 to the terminal position P2 through the moving mechanism 25. The plurality of jaws 4 are pushed by the wedge 3 and open to a maximum opening whose diameter is larger than the second opening (ST08). The controller 9 reverses the motor 20. The wedge 3 retreats 12 mm from the terminal position P2 to the initial position P1 through the moving mechanism 25. The plurality of jaws 4 close from the maximum opening to the closed position and rotate around the screw shaft axis K through the rotating mechanism 30 (ST09). The plurality of jaws 4 rotate 45° counterclockwise when viewed from the front, for example. The controller 9 stops the motor 20 and ends a series of diameter expansion actions. In addition, the first forward position and the second forward position are calculated by the controller 9 based on the signals sent from the initial position sensor 29a and the rotation speed detection sensor 20d, respectively.

[0063] Each of the above steps is executed when the user pulls the trigger 6. For example, when the user stops pulling the trigger 6, the switch 6a stops sending the on signal to the controller 9. The controller 9 reverses the motor 20 to retreat the wedge 3 to the initial position P1. When the controller 9 detects that the wedge 3 has returned to the initial position P1 through the signal sent from the initial position sensor 29a, the motor 20 stops. The plurality of jaws 4 close to the closed position. In this way, even when the user stops pulling the trigger 6 before a series of diameter expansion operations are completed, the position of the wedge 3 and the opening of the plurality of jaws 4 can be returned to the initial state and the motor 20 can be stopped.

[0064] When the end 60b of the tube 60 is expanded while changing the opening of the plurality of jaws 4 by changing the stroke amount of the wedge 3 as in the first example, it is possible to suppress the breakage of the end 60b of the tube 60, as compared with the case where the end 60b of the tube 60 is expanded by a single expansion operation. For example, when a test was conducted to expand the end of an annealed copper tube with an outer diameter of 3 / 8 inches and a wall thickness of 0.8 mm or an end of a work-hardened copper tube with an outer diameter of 1 inch and a wall thickness of 1.5 mm by a single expansion operation, cracks occurred at the end of each tube. For example, by performing the expansion operation by changing the stroke amount of the wedge 3 three times as in the first example, it is possible to expand the end of the tube while suppressing cracks.

[0065] In addition, for example, as in the first example, the end 60b of the tube 60 is expanded by the expansion operation in which the stroke amount of the wedge 3 is changed three times, so that the output of the motor 20 can be reduced. The end 60b of the tube 60 is expanded by the combined force of the output of the motor 20 and the force of the inertial action of the rotating body such as the rotor 20c, the screw shaft 27, the wedge 3, etc. When the end 60b of the tube 60 is expanded by a single expansion operation, the expansion can be carried out by a large inertial force at the beginning of the expansion, but the inertial force decreases as the expansion is near the end. Therefore, it is necessary to increase the output of the motor 20 at the end of the expansion when the force required for the expansion is large. Therefore, the peak value of the current flowing in each electronic component also increases, and it is necessary to provide an electronic component that can withstand the peak value of the current. As in the first example, when the end 60b of the tube 60 is expanded by the expansion operation in which the stroke amount of the wedge 3 is changed three times, the expansion operation at the beginning with a large inertial force is performed three times. Therefore, the output of the motor 20 can be reduced at the end of the expansion of each operation. This can suppress the peak value of the current flowing through each electronic component.

[0066] Next, according to Fig. 9 , 10 , 15, and 17 show a second example of the action of the wedge 3 and the plurality of jaws 4. In the second example, the actions are performed in the same manner as in the first example until ST01 to ST06. After ST06 is completed, the controller 9 reverses the motor 20. The wedge 3 is retracted 4 mm from the second forward position to the first retracted position that is forward of the initial position P1 via the moving mechanism 25. The plurality of jaws 4 are closed to an opening whose diameter is smaller than the second opening and larger than the closed position, and are rotated around the screw shaft axis K via the rotating mechanism 30 (ST11). At this time, the opening of the plurality of jaws 4 is approximately the first opening. The plurality of jaws 4 are rotated, for example, 15° counterclockwise when viewed from the front.

[0067] The controller 9 rotates the motor 20 in the forward direction. The wedge 3 advances 8 mm from the first retracted position to the terminal position P2 through the moving mechanism 25. The plurality of jaws 4 are pushed by the wedge 3 and open to the maximum opening (ST12). The controller 9 rotates the motor 20 in the reverse direction. The wedge 3 retreats 12 mm from the terminal position P2 to the initial position P1 through the moving mechanism 25. The plurality of jaws 4 close from the maximum opening to the closed position and rotate around the screw shaft axis K through the rotating mechanism 30 (ST13). The plurality of jaws 4 rotate 45° in the counterclockwise direction when viewed from the front, for example. The controller 9 stops the motor 20 to end a series of diameter expansion operations. In the case of the second example, the distance between the initial position P1 and the first retracted position in ST11 and ST12 is shorter than that in the first example, so that the moving distance of the wedge 3 is shortened. In addition, the first forward position, the second forward position, and the first retracted position are calculated by the controller 9 based on the signals sent from the initial position sensor 29a and the rotation speed detection sensor 20d, respectively.

[0068] The above steps are executed when the user pulls the trigger 6. For example, when the user stops pulling the trigger 6, the controller 9 stops the motor 20 while returning the wedge 3 to the initial position P1 and closing the plurality of jaws 4 to the closed position, as in the first example.

[0069] Next, according to Fig. 9 , 10 , 15, and 18 show a third example of the action of the wedge 3 and the plurality of jaws 4. In the third example, the actions are performed in the same manner as in the first example until ST01 to ST08. After ST08 is completed, the controller 9 reverses the motor 20. The wedge 3 is retracted 12 mm from the terminal position P2 to the initial position P1 by the moving mechanism 25. The plurality of jaws 4 are closed from the maximum opening to the closed position and rotated around the screw shaft axis K by the rotating mechanism 30 (ST21). The plurality of jaws 4 are rotated 45° counterclockwise, for example, when viewed from the front.

[0070] After ST21, the controller 9 determines whether the trigger 6 is kept pulled and the on signal is continuously received from the switch 6a (ST22). When the controller 9 receives the on signal from the switch 6a, it rotates the motor 20 forward. The wedge 3 advances 12 mm from the initial position P1 to the terminal position P2 through the moving mechanism 25. The multiple jaws 4 are pushed by the wedge 3 and opened to the maximum opening (ST23). After that, ST21 and ST22 are executed again. In this way, the wedge 3 repeatedly moves back and forth between the initial position P1 and the terminal position P2. When the multiple jaws 4 are repeatedly opened and closed between the closed position and the maximum opening and rotate around the screw shaft axis K when closed. Therefore, the end 60b (refer to Figure 3 ) is shaped into a cylindrical leveling action.

[0071] When the controller 9 does not receive the ON signal from the switch 6a at the time point of ST22, the motor 20 is stopped. Thus, a series of diameter expansion operations are completed in a state where the wedge 3 returns to the initial position P1 and the plurality of jaws 4 are closed to the closed position. For example, when the user stops pulling the trigger 6 during ST01 to ST08, the controller 9 stops the motor 20 in a state where the wedge 3 returns to the initial position P1 and the plurality of jaws 4 are closed to the closed position, similarly to the first example.

[0072] As described above, the end portion 60b of the tube 60 (see Figure 3 ) for expanding the diameter of the pipe 1 such as Fig. 9 , 10The pipe expansion tool 1 has a moving mechanism 25, which moves the wedge 3 forward and backward. The pipe expansion tool 1 has a plurality of jaws 4, which are pushed by the advancing wedge 3 and open radially outward. The pipe expansion tool 1 has a switch 6a, which sends an on signal when operated. The pipe expansion tool 1 has a controller 9 (see Figure 1 ). When the controller 9 receives the ON signal from the switch 6a, the wedge 3 is advanced to the first advanced position and the plurality of jaws 4 are opened at the first opening. The controller 9 retracts the wedge 3 and closes the plurality of jaws 4. The controller 9 advances the wedge 3 to the second advanced position which is forward of the first advanced position and the plurality of jaws 4 are opened at the second opening which is larger than the first opening. The controller 9 retracts the wedge 3 and closes the plurality of jaws 4. In addition, in the present invention, the second advanced position also includes the front end position where the wedge 3 can move, that is, the terminal position.

[0073] Therefore, when the switch 6a is turned on, the wedge 3 is first advanced to the first advanced position. The plurality of jaws 4 expand the diameter of the end 60b of the tube 60 to the first opening. Then, after the wedge 3 is retracted to close the plurality of jaws 4, the wedge 3 is advanced to the second advanced position. The plurality of jaws 4 expand the diameter of the end 60b of the tube 60 to the second opening larger than the first opening. In this way, the opening of the plurality of jaws 4 can be changed by changing the advanced position of the wedge 3. Thus, the diameter of the end 60b of the tube 60 can be expanded in stages. By expanding the diameter of the end 60b of the tube 60 in stages, the diameter of the end 60b of the tube 60 can be expanded to the target diameter while suppressing the occurrence of cracks or other damages in the end 60b of the tube 60 during the expansion.

[0074] like Fig.12 , 13 As shown in FIG. 1 , the pipe expansion tool 1 has a rotating mechanism 30, which rotates the plurality of jaws 4 around the axis of the wedge 3 in conjunction with the retreat of the wedge 3. Therefore, each jaw 4 changes its position around the axis of the wedge 3 each time it is closed. Therefore, each jaw 4 changes its position relative to the inner circumferential surface 60a (see FIG. 1 ) of the end 60b of the pipe 60 around the axis of the wedge 3 each time it expands the diameter. Figure 3 ) contacting portion. Therefore, by performing multiple diameter expansion operations, the opening shape of the end portion 60b of the expanded tube 60 can be made close to a perfect circle. Thus, the end portion 60b of the tube 60 can be expanded uniformly, and the generation of cracks and other damages at the end portion 60b of the tube 60 can be suppressed.

[0075] like Fig.16As shown, the controller 9 advances the wedge 3 from the initial position P1 to the first advanced position. The controller 9 retreats the wedge 3 from the first advanced position to the initial position P1. The controller 9 advances the wedge 3 from the initial position P1 to the second advanced position. The controller 9 retreats the wedge 3 from the second advanced position to the initial position P1. Therefore, each time the wedge 3 is retreated to the initial position P1, the plurality of jaws 4 are reliably closed to the closed position. Therefore, the plurality of jaws 4 are prevented from contacting the end 60b (refer to the FIG. 6B ) of the tube 60 while rotating around the axis of the wedge 3 and closing. Figure 3 ) contact. Thus, it is possible to prevent the plurality of jaws 4 from biting the end 60b of the tube 60, and the plurality of jaws 4 can be opened and closed smoothly.

[0076] like Fig.17 As shown in FIG. 1 , the controller 9 advances the wedge 3 from the initial position P1 to the second advanced position. The controller 9 retreats the wedge 3 from the second advanced position to the first retreated position that is forward of the initial position P1. The controller 9 advances the wedge 3 from the first retreated position to a position forward of the second advanced position. Therefore, by setting the first retreated position forward of the initial position P1, the total movement amount of the wedge 3 can be suppressed. As a result, the end 60b (see FIG. 1 ) of the tube 60 can be made Figure 3 ) Rapid diameter expansion.

[0077] like Fig.16 As shown in FIG. 1 , the controller 9 moves the wedge 3 forward and backward a plurality of times while receiving the on signal from the switch 6a, and moves the wedge 3 closer to the terminal position P2 each time. After the wedge 3 reaches the terminal position P2, the controller 9 returns the wedge 3 and stops it at the initial position P1. Therefore, when the wedge 3 reaches the terminal position P2, the plurality of grippers 4 hold the end 60b of the tube 60 (see FIG. 1 ). Figure 3 ) to the maximum opening. By returning the wedge 3 and stopping it at the initial position P1 after the end 60b of the tube 60 is expanded, it is possible to quickly shift to a preparation state for expanding the end 60b of the next tube 60. As a result, the operation time for expanding the end 60b of a plurality of tubes 60 can be shortened, thereby improving the workability.

[0078] like Fig.18 As shown in FIG. 1 , the controller 9 moves the wedge 3 forward and backward multiple times while receiving the ON signal from the switch 6a, and moves the wedge 3 closer to the terminal position P2 each time. After the wedge 3 reaches the terminal position P2, the controller 9 moves the wedge 3 backward. The controller 9 moves the wedge 3 forward again to the terminal position P2. Therefore, when the wedge 3 reaches the terminal position P2, the plurality of clamping jaws 4 expand the diameter of the end 60b of the tube 60 to the maximum opening. By repeatedly opening the plurality of clamping jaws 4 to the maximum opening and closing the clamping jaws 4, the opening shape of the end 60b of the tube 60 opened to the maximum opening can be made closer to a perfect circle.

[0079] like Figure 2As shown in FIG. 1 , the pipe expansion tool 1 has an input unit 18 for inputting the number of forward and backward movements of the wedge 3. The input unit 18 sends a signal of the number of times to the controller 9. Therefore, the number of forward and backward movements of the wedge 3 can be changed according to, for example, the diameter, wall thickness, or material of the pipe 60. As a result, the end 60b (see FIG. 1 ) of the pipe 60 during the expansion can be effectively suppressed. Figure 3 ) may cause cracks or other damage.

[0080] like Fig.15 , 16 As shown, the controller 9 calculates the first and second advanced positions based on the number of times information. Therefore, the controller 9 can calculate the first and second advanced positions to efficiently move the wedge 3. This can improve the work efficiency.

[0081] like Fig.15 As shown, the pipe expansion tool 1 has an initial position sensor 29a, which detects the initial position P1 of the wedge 3 (see Fig. 9 ) and sends a signal to the controller 9. The pipe expansion tool 1 has an end position sensor 29b, which detects the end position P2 of the wedge 3 (refer to Fig.10 ) and sends a signal to the controller 9. The pipe expansion tool 1 has a motor 20, and the motor 20 drives the moving mechanism 25. The pipe expansion tool 1 has a rotation speed detection sensor 20d, and the rotation speed detection sensor 20d detects the rotation speed of the motor 20. The controller 9 calculates the position of the wedge 3 based on the signal from the rotation speed detection sensor 20d. Therefore, the position of the wedge 3 relative to the initial position P1 or the terminal position P2 can be quickly detected by detecting the rotation speed of the motor 20. Therefore, the movement of the wedge 3 and the opening and closing of the plurality of jaws 4 can be smoothly operated.

[0082] like Fig. 9 , 10 As shown in FIG. 1 , the moving mechanism 25 includes a screw shaft 27, and the screw shaft 27 is provided on the wedge 3. The moving mechanism 25 includes an internal thread member 26, and the internal thread member 26 is screwed with the screw shaft 27 and rotates around the axis of the screw shaft 27 to move the screw shaft 27 forward and backward. Therefore, in the pipe expansion tool 1 that converts the rotation of the internal thread member 26 into the forward and backward movement of the screw shaft 27 and the wedge 3, it is also possible to move the wedge 3 to a plurality of forward positions and open a plurality of jaws 4 at different openings. As a result, the end 60b of the pipe 60 can be expanded while suppressing the occurrence of damage such as cracks.

[0083] Various changes can be made to the pipe expansion tool 1 of the present embodiment described above. An example of a pipe expansion tool 1 having six jaws 4 is given. Instead of this, for example, there may be five or less or seven or more jaws 4. It is also possible to replaceably mount a plurality of other types of jaws 4 with different closed diameters D1, maximum opening diameters D2, front-to-back lengths, etc. together with the end cap 2 on the tool body 10. The pipe 60 to be expanded is not limited to a copper pipe, and may be, for example, another type of metal pipe or a resin pipe such as a PEX pipe.

[0084] The example shows a rotation mechanism 30 that rotates the plurality of jaws 4 in the counterclockwise direction when viewed from the front. Instead, a structure that rotates the plurality of jaws 4 in the clockwise direction when viewed from the front may be used. In this case, the rotation direction of the front shaft 32 that transmits power to the drive side gear 43 from the one-way clutch 42 is counterclockwise when viewed from the front ( Figure 6 The direction of the first rotation R1 is shown).

[0085] The moving mechanism 25 is exemplified as a ball screw mechanism in which a ball 27b is sandwiched between the external thread 27a of the screw shaft 27 and the internal thread 26b of the internal thread member 26. Instead of this, for example, a feed screw mechanism in which the external thread 27a and the internal thread 26b are composed of trapezoidal threads and are directly screwed together may be used. As a mechanism for moving the wedge 3 forward and backward, for example, a cam mechanism that rotates a cam using the output of the motor 20 may be provided instead of the moving mechanism 25. By switching the rotation direction of the cam of the cam mechanism forward and reverse, an action that gradually changes the forward and backward movement of the wedge 3 can be performed. As a mechanism for moving the wedge 3 forward and backward, for example, a hydraulic mechanism may be provided instead of the moving mechanism 25.

[0086] The example shows an expansion action of expanding the diameter of the end 60b of the tube 60 in three steps. Instead of this, for example, the end 60b of the tube 60 may be expanded in two or four or more expansion actions. The position where the wedge 3 is moved forward and backward is not limited to the examples in the first to third examples, and may be changed appropriately. For example, the wedge 3 may be first advanced to the first advanced position two or more times, and then the advanced position may be changed to the second advanced position. For example, the wedge 3 may be advanced to the second advanced position two or more times, and then the advanced position may be changed to the third advanced position that is forward of the second advanced position. For example, the first retreat position may be set to the front or rear of the first advance position. For example, in addition to the action of retreating to the first retreat position, the action of retreating to the second retreat position that is forward of the first retreat position may also be included.

[0087] The example shows a diameter expansion action in which the first forward position, the second forward position and the terminal position P2 are respectively arranged at 4mm, 8mm and 12mm in proportion to the initial position P1. The distance from the initial position P1 to each position is not limited to a proportional manner or a linear function manner, and can be appropriately changed. The distance from the initial position P1 to the first forward position, the second forward position and the terminal position P2 can be, for example, 6mm, 9mm, 12mm, for example, 8mm, 10mm, 12mm, and for example, 5mm, 10mm, 12mm. For example, the leveling action of the third example can be added to the diameter expansion action of the second example.

[0088] The structure in which the plurality of jaws 4 are opened and closed by continuously pulling the trigger 6 to move the wedge 3 forward and backward is exemplified. Instead, for example, a structure in which the pipe expansion tool 1 can be continuously driven even if the trigger 6 is stopped immediately after being pulled. In this case, once the trigger 6 is pulled and the switch 6a sends an on signal to the controller 9, the controller 9 continues to drive the motor 20 until the wedge 3 completes a predetermined number of forward and backward movements. It is assumed that the disconnection operation will not be performed even if the trigger 6 is stopped, and the motor 20 is continuously driven until other disconnection operations such as emergency stop operations are performed.

[0089] The trigger 6 is shown as an example, which is pulled to turn on the switch 6a to start the pipe expanding tool 1. The operation unit for starting the pipe expanding tool 1 is not limited to the trigger 6, and may be, for example, a push button that turns on the switch 6a by pressing.

Claims

1. A pipe expansion tool for expanding the diameter of the end of a pipe, characterized in that: have: A moving mechanism, a plurality of grippers, a switch and a controller, wherein: The moving mechanism moves the wedge forward and backward; The plurality of clamping jaws are pushed by the advancing wedge to open radially outward relative to each other; The switch sends an on signal by being operated, When the controller receives the on signal from the switch, advancing the wedge to a first advanced position so that the plurality of jaws are opened at a first opening degree, retracting the wedge to close the plurality of jaws, The wedge is advanced to a second advanced position forward of the first advanced position to open the plurality of jaws to a second opening greater than the first opening, The wedge is retracted to close the plurality of jaws.

2. The pipe expansion tool according to claim 1, characterized in that: A rotating mechanism is provided, which rotates the plurality of clamping claws around the axis of the wedge in conjunction with the retreat of the wedge.

3. The pipe expansion tool according to claim 1 or 2, characterized in that: The controller is configured as follows: advancing the wedge from an initial position to the first advanced position, causing the wedge to retreat from the first advanced position to the initial position, advancing the wedge from the initial position to the second advanced position, The wedge is retracted from the second advanced position toward the initial position.

4. The pipe expansion tool according to claim 1 or 2, characterized in that: The controller is configured as follows: advancing the wedge from the initial position to the second advanced position, The wedge is retracted from the second forward position to a first retracted position forward of the initial position, The wedge is advanced from the first retracted position to a position forward of the second advanced position.

5. The pipe expansion tool according to any one of claims 1 to 4, characterized in that: The controller is configured as follows: During the period of receiving the on signal from the switch, The wedge is moved forward and backward a plurality of times, each advance bringing the wedge closer to the terminal position, After the wedge reaches the terminal position, the wedge is returned and stopped at the initial position.

6. The pipe expansion tool according to any one of claims 1 to 4, characterized in that: The controller is configured as follows: During the period of receiving the on signal from the switch, The wedge is moved forward and backward a plurality of times, each advance bringing the wedge closer to the terminal position, After the wedge reaches the terminal position, the wedge is retracted. The wedge is advanced again into the end position.

7. The pipe expansion tool according to any one of claims 1 to 6, characterized in that: An input unit is provided to input the number of times the wedge moves forward and backward, and the input unit sends a signal of number information to the controller.

8. The pipe expansion tool according to claim 7, characterized in that: The controller calculates the first advanced position and the second advanced position based on the number of times information.

9. The pipe expansion tool according to any one of claims 1 to 8, characterized in that: It has an initial position sensor, a terminal position sensor, a motor and a speed detection sensor, wherein: The initial position sensor detects the initial position of the wedge and sends a signal to the controller; The terminal position sensor detects the terminal position of the wedge and sends a signal to the controller; The motor drives the moving mechanism; The rotation speed detection sensor detects the rotation speed of the motor. The controller calculates the position of the wedge based on the signal from the rotation speed detection sensor.

10. The pipe expansion tool according to any one of claims 1 to 9, characterized in that: The moving mechanism includes a screw shaft and an internal thread component. The screw shaft is provided on the wedge. The internal thread component is screwed with the screw shaft and rotates around the axis of the screw shaft to move the screw shaft forward and backward.

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