Electrically-driven fastening device

Abstract

To suppresses falling of a screw that fixes an outer intermediate sleeve and an outer sleeve.SOLUTION: An electrically-driven fastening device comprises: a motor; a planetary gear mechanism with an internal gear to which torque of the motor is inputted; an outer intermediate sleeve which is arranged at an inner side of a front end part of the internal gear in a radial direction and to which torque of the planetary gear mechanism is inputted; an inner intermediate sleeve which is arranged at an inner side of the outer intermediate sleeve in the radial direction and to which torque of the planetary gear mechanism is inputted; an outer sleeve which is arranged at an inner side of a front end part of the outer intermediate sleeve in the radial direction to hold a nut; an inner sleeve which is arranged at an inner side of the outer sleeve in the radial direction to hold a pin tail of a shear bolt; a screw which fixes the outer intermediate sleeve and the outer sleeve; and a cover member which covers the screw from an outer side in the radial direction.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The technology disclosed in this specification relates to an electric fastening machine. [Background technology]

[0002] In the technical field related to electric fastening machines, a shear wrench as disclosed in Patent Document 1 is known. The shear wrench is used for fastening a shear bolt and a nut. In Patent Document 1, the shear wrench has an outer intermediate sleeve (200) and an outer sleeve (204) disposed in front of the outer intermediate sleeve (200). The outer intermediate sleeve and the outer sleeve are fixed together by a screw. The outer sleeve is replaced according to the size of the nut. An operator can replace the outer sleeve by releasing the screw that fixes the outer intermediate sleeve and the outer sleeve together. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-018312 A Summary of the Invention [Problem to be solved by the invention]

[0004] For example, the screw that fastens the outer intermediate sleeve and the outer sleeve may become loose due to vibrations caused by the tightening operation. If the loosened screw falls off the shear wrench, the screw may be lost.

[0005] The technology disclosed in this specification aims to prevent the screws that fasten the outer intermediate sleeve and the outer sleeve from falling off. [Means for solving the problem]

[0006] This specification discloses an electric tightening machine. The electric tightening machine may include a motor, a planetary gear mechanism including an internal gear to which the rotational force of the motor is input, an outer intermediate sleeve arranged radially inside the front end of the internal gear and to which the rotational force of the planetary gear mechanism is input, an inner intermediate sleeve arranged radially inside the outer intermediate sleeve and to which the rotational force of the planetary gear mechanism is input, an outer sleeve arranged radially inside the front end of the outer intermediate sleeve and holding a nut, an inner sleeve arranged radially inside the outer sleeve and holding a pintail of a shear bolt, and a screw that fixes the outer intermediate sleeve and the outer sleeve. The electric tightening machine may include a cover member that covers the screw from the radial outside. Effect of the Invention

[0007] According to the technique disclosed in this specification, the screws that fasten the outer intermediate sleeve and the outer sleeve are prevented from falling off. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing an electric fastening device according to a first embodiment, seen from the right front. [Diagram 2] FIG. 2 is a perspective view showing the electric fastening device according to the first embodiment, seen from the left rear. [Diagram 3] FIG. 3 is a right side view showing the electric fastening device according to the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing the electric fastening device according to the first embodiment. [Diagram 5] FIG. 5 is a perspective view showing the front end portion of the electric fastening device according to the first embodiment, seen from the left front. [Figure 6] FIG. 6 is an exploded perspective view showing the front end portion of the electric fastening device according to the first embodiment, as viewed from the front left. [Figure 7] FIG. 7 is a right side view showing the front end portion of the electric fastening device according to the first embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing a front end portion of the electric fastening device according to the first embodiment. [Figure 9]FIG. 9 is a perspective view showing the front end portion of the electric fastening device according to the first embodiment, seen from the left front. [Figure 10] FIG. 10 is a right side view showing the front end portion of the electric fastening device according to the first embodiment. [Figure 11] FIG. 11 is a cross-sectional view showing a front end portion of the electric fastening device according to the first embodiment. [Figure 12] FIG. 12 is a perspective view showing the front end portion of the electric fastening device according to the second embodiment, seen from the left front. [Figure 13] FIG. 13 is an exploded perspective view showing the front end portion of the electric fastening device according to the second embodiment, as viewed from the front left. [Figure 14] FIG. 14 is a right side view showing the front end portion of the electric fastening device according to the second embodiment. [Figure 15] FIG. 15 is a cross-sectional view showing a front end portion of the electric fastening device according to the second embodiment. [Figure 16] FIG. 16 is a cross-sectional view showing a front end portion of the electric fastening device according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In one or more embodiments, the electric tightening machine may include a motor, a planetary gear mechanism including an internal gear to which a rotational force of the motor is input, an outer intermediate sleeve disposed radially inside a front end of the internal gear and to which the rotational force of the planetary gear mechanism is input, an inner intermediate sleeve disposed radially inside the outer intermediate sleeve and to which the rotational force of the planetary gear mechanism is input, an outer sleeve disposed radially inside a front end of the outer intermediate sleeve and holding a nut, an inner sleeve disposed radially inside the outer sleeve and holding a pintail of a shear bolt, and a screw that fixes the outer intermediate sleeve and the outer sleeve. The electric tightening machine may include a cover member that covers the screw from the radial outside.

[0010] In the above configuration, the cover member that covers the screw is provided, so that even if the screw becomes loose, the cover member prevents the screw from falling off.

[0011] In one or more embodiments, the cover member may be attached to the outer intermediate sleeve.

[0012] In the above-described configuration, an operator can, for example, replace the outer sleeve while the cover member is attached to the outer intermediate sleeve, which reduces the risk of losing the cover member.

[0013] In one or more embodiments, the outer intermediate sleeve may have a screw hole into which the screw is coupled. The outer sleeve may have a through hole into which the tip of the screw is inserted. The cover member may be movable between a position that covers the screw hole and a position that exposes the screw hole when attached to the outer intermediate sleeve.

[0014] In the above configuration, the operator can perform a tightening operation using an electric tightening machine while the cover member is placed in a position that covers the screw holes. The operator can also perform, for example, an outer sleeve replacement operation while the cover member is placed in a position that exposes the screw holes.

[0015] In one or more embodiments, the cover member may be movable circumferentially about the outer intermediate sleeve.

[0016] In the above configuration, an operator can move the cover member in the circumferential direction to a position where the cover member covers the screw hole and a position where the cover member exposes the screw hole.

[0017] In one or more embodiments, the cover member may be a strip disposed about a portion of the circumference of the outer intermediate sleeve.

[0018] In the above configuration, the shape or structure of the cover member is prevented from becoming complicated.

[0019] In one or more embodiments, the cover member may generate a resilient force to clamp the outer intermediate sleeve.

[0020] In the above configuration, the elastic force of the cover member prevents the cover member from moving unnecessarily or from falling off the outer intermediate sleeve. When the cover member is attached to the outer intermediate sleeve, the cover member can be attached to the outer intermediate sleeve by expanding the diameter of the cover member against the elastic force of the cover member.

[0021] In one or more embodiments, the cover member may have an opening. The position that blocks the screw hole may be a position where a non-opening of the cover member coincides with the screw hole. The position that exposes the screw hole may be a position where an opening coincides with the screw hole.

[0022] In the above configuration, an opening is provided in a part of the cover member, so that an operator can expose the screw hole by moving the cover member in the circumferential direction so that the opening aligns with the screw hole.

[0023] In one or more embodiments, the cover member may have a protrusion that protrudes radially inward. The position that blocks the screw hole may be a position where the protrusion coincides with the screw hole.

[0024] In the above configuration, a protrusion is provided on a portion of the non-opening part of the cover member, so that an operator can cover the screw hole by moving the cover member circumferentially so that the protrusion aligns with the screw hole.

[0025] In one or more embodiments, the protrusion may be contactable against an edge of the outer intermediate sleeve that defines a radially outer opening of the screw hole.

[0026] In the above configuration, the protrusion contacts the edge of the outer intermediate sleeve with the position of the protrusion coinciding with the position of the screw hole, so that the cover member is positioned relative to the outer intermediate sleeve, thereby preventing the cover member from moving unnecessarily during a fastening operation using, for example, an electric fastening machine.

[0027] In one or more embodiments, the cover member may be axially movable relative to the outer intermediate sleeve.

[0028] In the above configuration, an operator can move the cover member in the axial direction to a position that covers the screw hole and a position that exposes the screw hole.

[0029] In one or more embodiments, the cover member may be annular and disposed about the outer intermediate sleeve.

[0030] In the above configuration, since the cover member is provided so as to surround the outer intermediate sleeve, the cover member is prevented from falling off the outer intermediate sleeve.

[0031] In one or more embodiments, the cover member may include an arcuate first cover member and an arcuate second cover member secured to the first cover member.

[0032] In the above configuration, since the cover member has a so-called half-split structure, the cover member can be disposed around the outer intermediate sleeve.

[0033] In one or more embodiments, the first cover member and the second cover member may be fixed together by a first protrusion provided at one end of the first cover member being pressed into a first recess provided at one end of the second cover member, and a second protrusion provided at the other end of the second cover member being pressed into a second recess provided at the other end of the first cover member.

[0034] In the above configuration, the first cover member and the second cover member are fixed together without using, for example, an adhesive.

[0035] In one or more embodiments, the position at which the screw hole is exposed may be a position at which the cover member is disposed rearward of the screw hole.

[0036] In the above configuration, an operator can move the cover member, which is disposed in a position covering the screw holes, backwards, thereby moving the cover member from a position covering the screw holes to a position exposing the screw holes.

[0037] In one or more embodiments, the electric tightening machine may include a spring that generates a resilient force to move the cover member to a position that covers the screw hole.

[0038] In the above-described configuration, the cover member can move from a position exposing the screw hole to a position covering the screw hole by the elastic force of the spring.

[0039] In one or more embodiments, the cover member may have a ring portion and a stopper portion protruding radially inward from the ring portion. The outer intermediate sleeve may have a large diameter portion in which the screw hole is provided and a small diameter portion provided rearward of the large diameter portion. The spring and the stopper portion may be disposed around the small diameter portion.

[0040] In the above configuration, the ring portion can be disposed around the large diameter portion.

[0041] In one or more embodiments, a front end of the spring may contact a rear surface of the stopper portion and a rear end of the spring may contact a rear support surface provided at the rear end of the reduced diameter portion.

[0042] In the above configuration, the spring can generate an elastic force so as to move the ring portion from a position exposing the screw hole to a position covering the screw hole.

[0043] In one or more embodiments, when the ring portion is positioned to block the screw hole, the front surface of the stopper portion may contact a front support surface provided at the front end of the small diameter portion.

[0044] In the above-mentioned configuration, the ring portion is positioned at a position where it covers the screw hole. The elastic force of the spring presses the stopper portion against the front support surface of the outer intermediate sleeve, thereby preventing the cover member from moving unnecessarily.

[0045] In one or more embodiments, the front support surface may be angled forwardly toward the radially outward direction.

[0046] In the above-described configuration, the stopper portion comes into contact with the front support surface that is inclined forward toward the outside in the radial direction, whereby the ring portion is positioned at a position where it covers the screw hole.

[0047] In one or more embodiments, when the ring portion is positioned to block the screw hole, the front end of the ring portion and the front end of the screw hole may coincide.

[0048] In the above-described configuration, the ring portion is prevented from becoming large, and in particular, the axial dimension of the ring portion is prevented from becoming excessively large.

[0049] Hereinafter, an embodiment will be described with reference to the drawings. In the embodiment, the positional relationship of each part will be described using the terms left, right, front, rear, top, and bottom. These terms indicate relative positions or directions based on the center of the electric fastening device 1.

[0050] [First embodiment] A first embodiment will be described. Fig. 1 is a perspective view of an electric fastening machine 1 according to this embodiment, seen from the front right. Fig. 2 is a perspective view of an electric fastening machine 1 according to this embodiment, seen from the rear left. Fig. 3 is a right side view of the electric fastening machine 1 according to this embodiment. Fig. 4 is a cross-sectional view of the electric fastening machine 1 according to this embodiment.

[0051] In this embodiment, the electric tightening machine 1 is a shear wrench. The electric tightening machine 1 may be a primary tightening wrench. The electric tightening machine 1 is used for tightening a shear bolt and a nut. The primary tightening wrench is used for a provisional tightening operation (primary tightening operation) in which the shear bolt and the nut are tightened with a first torque. The shear wrench is used for a main tightening operation in which the shear bolt and the nut tightened with the primary tightening wrench are tightened with a second torque higher than the first torque. The main tightening operation separates the pintail provided on the shear bolt from the shear bolt.

[0052] <Shear wrench> The electric tightening machine 1 includes a housing 2, a power unit 6, a power transmission unit 4, a sleeve mechanism 18, a handle unit 7, and a battery attachment unit 9. The housing 2 directly or indirectly holds various components constituting the electric tightening machine 1. The power unit 6 generates a rotational force. The power transmission unit 4 transmits the rotational force generated by the power unit 6 to the sleeve mechanism 18. The central axis AX of the power transmission unit 4 and the sleeve mechanism 18 extends in the front-rear direction. The power unit 6 is disposed so as to protrude downward from the central lower part of the power transmission unit 4. The handle unit 7 is disposed so as to protrude downward from the rear lower part of the power transmission unit 4. The battery attachment unit 9 is disposed so as to connect the lower part of the power unit 6 and the lower part of the handle unit 7. A battery 8 is attached to the battery attachment unit 9.

[0053] The power unit 6 includes a motor 11 having a rotor shaft 10. The rotation axis of the rotor shaft 10 extends in the vertical direction. At least a part of the power transmission unit 4 is disposed rearward of the sleeve mechanism 18. The power transmission unit 4 includes an intermediate gear mechanism 12 to which the rotation force of the motor 11 is input, and a planetary gear mechanism 14 to which the rotation force of the motor 11 is input via the intermediate gear mechanism 12. At least a part of the planetary gear mechanism 14 is disposed forward of the intermediate gear mechanism 12. The planetary gear mechanism 14 includes an internal gear 31. At least a part of the sleeve mechanism 18 is disposed forward of the planetary gear mechanism 14. The motor 11 is a drive source of the electric fastening tool 1. The rotation of the rotor shaft 10 is decelerated by the intermediate gear mechanism 12 and the planetary gear mechanism 14, and then transmitted to the sleeve mechanism 18.

[0054] The housing 2 includes a handle housing 20, a motor housing 24, a gear housing 26, a rear cover 28, and a gear case 30. The handle housing 20 is a so-called split housing, and includes a left handle housing 21 and a right handle housing 22. The handle housing 20 and the motor housing 24 are arranged so as to extend downward from the lower part of the gear housing 26. The motor housing 24 is arranged forward of the handle housing 20. The motor housing 24 holds the motor 11. The gear housing 26 holds the intermediate gear mechanism 12 and at least a part of the power transmission unit 4. The gear case 30 holds at least a part of the power transmission unit 4. The rear part of the gear case 30 is arranged above the gear housing 26. The rear cover 28 is arranged above the handle housing 20 so as to cover the rear openings of the gear housing 26 and the gear case 30. The gear housing 26 and the gear case 30 are made of metal. The gear housing 26 and the gear case 30 may be regarded as one unit. The rear cover 28 is made of synthetic resin. Since the rear cover 28 is made of synthetic resin, the weight of the housing 2 can be reduced.

[0055] The internal gear 31 is disposed so as to hold the sleeve mechanism 18. The internal gear 31 is disposed forward of the gear case 30.

[0056] The left handle housing 21 and the right handle housing 22 are fixed to each other by a plurality of screws 34. The gear housing 26 is sandwiched from above and below between the motor housing 24 and the gear case 30. The gear housing 26 is fixed to the motor housing 24 by a plurality of screws 35. The rear cover 28 is positioned in the handle housing 20. The rear cover 28 is fixed to the gear case 30 by screws 38.

[0057] A switch 44 and a trigger 45 are disposed at the upper end of the handle portion 7. The trigger 45 is operated by an operator to start the motor 11. The switch 44 and the trigger 45 are each held in the handle housing 20. The trigger 45 is disposed in front of the switch 44.

[0058] A battery 8 is attached to the battery attachment section 9. The battery 8 is a rechargeable battery. The battery 8 is a lithium ion battery. A controller 74 is disposed above the battery attachment section 9. A plurality of air vents 79 are provided at the bottom of the right handle housing 22. A partition rib 80 extending in all directions is disposed at the boundary between the battery attachment section 9 and the power section 6 inside the handle housing 20. The controller 74 is appropriately cooled by natural ventilation through the air vents 79 without relying on a fan 126. A plurality of air intakes 90 are provided at the bottom of the motor housing 24.

[0059] The motor 11 is an electric motor. The motor 11 is an inner rotor type brushless motor. The motor 11 has a stator 96 and a rotor 98 disposed inside the stator 96. The motor 11 is controlled by the controller 74.

[0060] The stator 96 includes a stator core and a plurality of coils attached to the stator core via insulators. A sensor circuit board 108 is fixed to the lower part of the stator 96.

[0061] The rotor 98 has a rotor shaft 10, a cylindrical stator core arranged around the rotor shaft 10, a permanent magnet arranged inside the stator core, and a sensor permanent magnet fixed to the lower part of the stator core so as to face a sensor circuit board 108. The rotor shaft 10 is fixed to the rotor core. A pinion 115 is provided at the upper end of the rotor shaft 10.

[0062] The sensor circuit board 108 has a magnetic sensor that detects the sensor permanent magnet to detect the rotational position of the rotor 98. The controller 74 controls the current supplied to the motor 11 based on the rotational position of the rotor 98 detected by the magnetic sensor of the sensor circuit board 108.

[0063] A bearing 122 that supports an upper part of the rotor shaft 10 is provided below the pinion 115. The bearing 122 is held by the gear housing 26. A bearing 124 that supports a lower part of the rotor shaft 10 is provided below the stator 96. The bearing 124 is held by the motor housing 24.

[0064] A fan 126 is disposed between the bearing 122 and the stator 96. The fan 126 is fixed to the rotor shaft 10. The fan 126 rotates due to the rotation of the rotor shaft 10. The rotation of the fan 126 generates an airflow around the motor 11, thereby cooling the motor 11. A plurality of exhaust ports 128 are provided in the gear housing 26. The air that has flowed around the motor 11 is exhausted from the exhaust ports 128.

[0065] The intermediate gear mechanism 12 has a first intermediate gear 130 that meshes with the pinion 115, and a second intermediate gear 132 that meshes with the first intermediate gear 130. The rotation shaft of the first intermediate gear 130 extends in the vertical direction. A bearing 134 that supports an upper portion of the first intermediate gear 130 is held by the gear case 30. A bearing 136 that supports a lower portion of the first intermediate gear 130 is held by the gear housing 26. The rotation shaft of the second intermediate gear 132 extends in the vertical direction. The second intermediate gear 132 is disposed rearward of the first intermediate gear 130. A bearing 138 that supports an upper portion of the second intermediate gear 132 is held by the gear case 30. A bearing 139 that supports a lower portion of the second intermediate gear 132 is held by the gear housing 26. A through hole is formed in the center of the second intermediate gear 132. The through hole of the second intermediate gear 132 extends in the vertical direction. A rod 140 is disposed in the through hole of the second intermediate gear 132. The lower end of the rod 140 contacts the upper end of the tip lever 56.

[0066] The planetary gear mechanism 14 reduces the speed of rotation of the rotor shaft 10 and transmits it to the sleeve mechanism 18. The planetary gear mechanism 14 has three stages of planetary gear trains arranged in the front-rear direction parallel to the central axis AX. The planetary gear mechanism 14 has a rear planetary gear train 150, a middle planetary gear train 160, and a front planetary gear train 170.

[0067] The rear planetary gear train 150 has bevel teeth 151 that mesh with the upper bevel tooth portion of the second intermediate gear 132, multiple (four) planetary gears 152 that each mesh with a sun gear portion formed in front of the bevel teeth 151, a pin and a carrier, and internal teeth portions formed on the inner surface of the internal gear 31 that mesh with the planetary gears 152. The front portion of the bevel teeth 151 is supported by a bearing 156. The rear portion of the bevel teeth 151 is supported by a bearing 157. The bevel teeth 151 rotate about the central axis AX.

[0068] The intermediate planetary gear train 160 has multiple (four) planetary gears 162 that mesh with a sun gear portion formed in the front part of the first stage carrier, a pin and carrier, and an internal tooth portion formed on the inner surface of the internal gear 31 that meshes with the planetary gears 162.

[0069] The front planetary gear train 170 has multiple (four) planetary gears 172 that mesh with a sun gear portion formed at the front of the second stage carrier, a pin 173, a carrier 174, and an internal tooth portion 175 that is held by the internal gear 31 and meshes with the planetary gears 172.

[0070] A tip rod 180 is disposed so as to pass through the center of the planetary gear mechanism 14. The tip rod 180 is disposed so as to extend in the front-rear direction. The tip rod 180 is movable in the front-rear direction. A push-out ring 182 is disposed at the rear of the tip rod 180. The push-out ring 182 contacts the rod 140.

[0071] The sleeve mechanism 18 is an output part of the electric fastening device 1. The central axis AX of the sleeve mechanism 18 extends in the front-rear direction. In the following description, the direction parallel to the rotation axis AX is appropriately referred to as the axial direction. The radial direction of the rotation axis AX is appropriately referred to as the radial direction. The direction going around the rotation axis AX is appropriately referred to as the circumferential direction or the rotation direction. In the radial direction, the position or the direction approaching the rotation axis AX is appropriately referred to as the radial inner side, and the position or the direction away from the rotation axis AX is appropriately referred to as the radial outer side. The position or the direction on one side in the circumferential direction is appropriately referred to as the circumferential one side, and the position or the direction on the other side in the circumferential direction is appropriately referred to as the circumferential other side. The position or the direction on one side in the axial direction is appropriately referred to as the axial one side, and the position or the direction on the other side in the axial direction is appropriately referred to as the axial other side. The axial one side is the front side, and the axial other side is the rear side.

[0072] The sleeve mechanism 18 can hold a shear bolt and a nut simultaneously. The sleeve mechanism 18 has an outer intermediate sleeve 200, an inner intermediate sleeve 202, an outer sleeve 204, and an inner sleeve 206.

[0073] The outer intermediate sleeve 200 is cylindrical. The outer intermediate sleeve 200 is disposed around the rotation axis AX. The rear end of the outer intermediate sleeve 200 is disposed radially inside the front end of the internal gear 31. The outer intermediate sleeve 200 is coupled to the planetary gear mechanism 14. In the embodiment, the outer intermediate sleeve 200 is coupled to the third stage internal tooth portion 175. The rotational force of the planetary gear mechanism 14 is input to the outer intermediate sleeve 200.

[0074] The inner intermediate sleeve 202 is cylindrical. The inner intermediate sleeve 202 is disposed around the rotation axis AX. The inner intermediate sleeve 202 is disposed radially inside the outer intermediate sleeve 200. The inner intermediate sleeve 202 is coupled to the planetary gear mechanism 14. In the embodiment, the inner intermediate sleeve 202 is coupled to the third stage carrier 174. The rotational force of the planetary gear mechanism 14 is input to the inner intermediate sleeve 202.

[0075] A bearing 210 is disposed between the outer intermediate sleeve 200 and the inner intermediate sleeve 202. An inner ring of the bearing 210 contacts the inner intermediate sleeve 202 and the third stage carrier. An outer ring of the bearing 210 contacts the outer intermediate sleeve 200. A bearing 211 is disposed between the center of the outer intermediate sleeve 200 and the front end of the inner intermediate sleeve 202. The bearing 211 is an oilless bearing.

[0076] The outer sleeve 204 is detachable from the outer intermediate sleeve 200. At least a portion of the outer sleeve 204 is disposed on the front side of the outer intermediate sleeve 200. The rear end portion of the outer sleeve 204 is disposed radially inside the front end portion of the outer intermediate sleeve 200. The outer intermediate sleeve 200 and the outer sleeve 204 are fixed together by a screw 222, which will be described later.

[0077] The inner sleeve 206 is detachably attached to the inner intermediate sleeve 202. At least a portion of the inner sleeve 206 is disposed on the front side of the inner intermediate sleeve 202. The inner sleeve 206 is disposed radially inside the outer sleeve 204. A rear end portion of the inner sleeve 206 is disposed radially inside a front end portion of the inner intermediate sleeve 202. The inner intermediate sleeve 202 and the inner sleeve 206 are spline-coupled.

[0078] The outer sleeve 204 and the inner sleeve 206 function as a tool tip of the electric fastening tool 1. The outer intermediate sleeve 200 and the inner intermediate sleeve 202 function as a tool tip holder of the electric fastening tool 1 that holds the tool tip.

[0079] The outer sleeve 204 is socket-shaped. The outer sleeve 204 holds a nut. A nut fitting portion into which the nut is fitted is formed on the inner peripheral surface of the front portion of the outer sleeve 204.

[0080] The inner sleeve 206 is socket-shaped. The inner sleeve 206 holds the pintail of a shear bolt. A bolt fitting portion into which the pintail of the shear bolt is fitted is formed on the inner peripheral surface of the front part of the inner sleeve 206.

[0081] The inner sleeve 206 is biased forward by an inner sleeve spring 212. The inner sleeve spring 212 is disposed between the third stage carrier 174 and the inner sleeve 206. The inner sleeve 206 has one pin 214 movable in the front-rear direction and a plurality of stoppers 216 disposed so as to extend radially outward from the pin 214. The rear portion of the pin 214 is thicker than the front portion of the pin 214. When the pin 214 is positioned forward, the rear portion of the pin 214 comes into contact with the inner end of the stopper 216 and pushes the stopper 216 radially outward. When the pin 214 is positioned rearward, the front portion of the pin 214 allows the stopper 216 to move radially inward. The stopper 216 pushed radially outward engages with the inner periphery of the outer sleeve 204.

[0082] The rear portion of the pin 214 comes into contact with a head portion 218 attached to the tip portion of the tip rod 180. The tip rod 180 and the head portion 218 are biased forward by a tip rod spring 220. The tip rod spring 220 is disposed between the third stage carrier 174 and the head portion 218. The pin 214 is pushed forward by the head portion 218.

[0083] When performing the tightening operation (main tightening operation) of the shear bolt and the nut, the worker inserts the pintail of the shear bolt into the inner sleeve 206. The shear bolt and the nut are provisionally tightened (primary tightening). When the pintail is completely inserted into the inner sleeve 206 against the biasing force of the tip rod spring 220, the pin 214 is pushed backward by the pintail, the stopper 216 moves radially inward, the engagement between the inner sleeve 206 and the outer sleeve 204 is released, the inner sleeve 206 is allowed to move backward, and the nut is allowed to be fitted into the outer sleeve 204. At this time, the tip rod 180 moves backward, and the rear end of the tip rod 180 passes through the push-out ring 182 and reaches the hole 40 provided in the rear cover 28.

[0084] The nut fitted into the outer sleeve 204 moves the inner sleeve 206 rearward against the biasing force of the inner sleeve spring 212. The nut is fitted into the outer sleeve 204 when the pintail of the shear bolt is completely fitted into the inner sleeve 206.

[0085] When an operator grips handle portion 7 and pulls trigger 45, switch 44 is turned on and power is supplied from battery 8 to motor 11 via controller 74, driving motor 11. Based on a detection signal indicating the rotational position of rotor 98 output from a magnetic sensor on sensor circuit board 108, controller 74 passes current through the coils of stator 96 in sequence, thereby rotating rotor 98 including rotor shaft 10.

[0086] Rotation of the rotor shaft 10 rotates the fan 126, causing air to flow from the intake port 90 to the exhaust port 128, and the air flow cools the motor 11 and various other components.

[0087] The rotational force of the rotor shaft 10 is transmitted from the pinion 115 via the first intermediate gear 130 and the second intermediate gear 132 to the planetary gear mechanism 14, and then transmitted to the sleeve mechanism 18 after being reduced in speed by the planetary gear mechanism 14. The rotational force of the third stage carrier 174 is transmitted to the inner intermediate sleeve 202 and the inner sleeve 206. The rotational force of the third stage internal teeth portion 175 is transmitted to the outer intermediate sleeve 200 and the outer sleeve 204. The direction of the rotational force of the third stage carrier 174 is opposite to the direction of the rotational force of the third stage internal teeth portion 175. As the internal teeth portion 175 rotates, the internal gear 31 rotates slowly.

[0088] During the tightening of the nut, the inner sleeve 206 is stopped by the shear bolt, and the rotational force of the outer sleeve 204 is transmitted to the nut, causing the nut to rotate relative to the shear bolt. In addition, the internal gear 31 rotates slowly in accordance with the rotation of the internal teeth portion 175.

[0089] When the tightening of the nut reaches the final stage and a reaction torque equal to or greater than a predetermined threshold value is applied to the outer sleeve 204, the rotation of the internal gear 31 is restricted via the third stage internal teeth portion 175. Then, the outer sleeve 204 integral with the third stage carrier 174 rotates in the direction opposite to the nut tightening direction against the rigidity of the pintail of the shear bolt, shearing the pintail. The pintail is separated from the shear bolt. In this way, the tightening of the nut to the shear bolt is completed, and the tightening of the nut accompanied by the separation of the pintail ensures that the nut is tightened to a predetermined torque.

[0090] When the nut is removed from the outer sleeve 204, the inner sleeve 206, which is biased forward by the inner sleeve spring 212, moves forward, and the stopper 216 engages with the outer sleeve 204. Inside the inner sleeve 206, there is a tip, which is a pintail separated from the shear bolt. The tip inside the inner sleeve 206 is urged to be discharged forward by the tip rod 180 and the pin 214, which are biased forward by the tip rod spring 220. Also, when the operator pulls the tip lever 56, the rod 140, which is pushed upward by the tip lever 56, pushes the push-out ring 182, which pushes the tip rod 180 and the pin 214 located at the rear forward, and the tip inside the inner sleeve 206 is discharged forward.

[0091] <Cover material> Fig. 5 is a perspective view of the front end of the electric fastening machine 1 according to this embodiment, seen from the front left. Fig. 6 is an exploded perspective view of the front end of the electric fastening machine 1 according to this embodiment, seen from the front left. Fig. 7 is a right side view of the front end of the electric fastening machine 1 according to this embodiment. Fig. 8 is a cross-sectional view of the front end of the electric fastening machine 1 according to this embodiment, and corresponds to the cross-sectional arrow view taken along line A1-A1 in Fig. 7.

[0092] The outer intermediate sleeve 200 has a plurality of claw portions 230 protruding forward from the outer intermediate sleeve 200. In this embodiment, four claw portions 230 are provided. The four claw portions 230 are arranged at equal intervals in the circumferential direction. A groove portion 232 is provided in the outer sleeve 204. The claw portions 230 are arranged in the groove portion 232. By arranging the claw portions 230 in the groove portion 232, relative rotation between the outer intermediate sleeve 200 and the outer sleeve 204 is suppressed. The claw portions 230 and the groove portion 232 function as a rotation prevention mechanism that suppresses relative rotation between the outer intermediate sleeve 200 and the outer sleeve 204.

[0093] The outer intermediate sleeve 200 and the outer sleeve 204 are fixed together by a plurality of screws 222. In this embodiment, the outer intermediate sleeve 200 and the outer sleeve 204 are fixed together by two screws 222.

[0094] As described above, the outer sleeve 204 is detachable from the outer intermediate sleeve 200. That is, the outer sleeve 204 is replaceable. The outer sleeve 204 is replaced according to the size of the nut. When removing the outer sleeve 204 from the outer intermediate sleeve 200, an operator uses a tool to release the fixation between the outer intermediate sleeve 200 and the outer sleeve 204 by the screw 222. The outer sleeve 204 is removed from the outer intermediate sleeve 200 by releasing the fixation between the outer intermediate sleeve 200 and the outer sleeve 204 by the screw 222. When fixing the outer sleeve 204 to the outer intermediate sleeve 200, an operator inserts the rear end of the outer sleeve 204 radially inside the front end of the outer intermediate sleeve 200, and then fixes the outer intermediate sleeve 200 and the outer sleeve 204 with the screw 222.

[0095] As described above, the inner sleeve 206 is detachable from the inner intermediate sleeve 202. The inner sleeve 206 is replaced according to the size of the pintail (sear bolt). An operator can replace the inner sleeve 206 with the outer sleeve 204 removed from the outer intermediate sleeve 200.

[0096] The outer intermediate sleeve 200 has a screw hole 224 in which an intermediate portion of the screw 222 is disposed. The screw hole 224 has a screw groove in which the thread of the screw 222 is connected. The screw 222 is coupled to the screw hole 224. The outer sleeve 204 has a through hole 226 into which the tip of the screw 222 is inserted. With the screw 222 coupled to the screw hole 224, the tip of the screw 222 is inserted into the through hole 226, thereby suppressing relative rotation between the outer intermediate sleeve 200 and the outer sleeve 204 and suppressing relative movement in the axial direction between the outer intermediate sleeve 200 and the outer sleeve 204. The screw 222 and the through hole 226 function as a positioning mechanism that suppresses relative movement between the outer intermediate sleeve 200 and the outer sleeve 204.

[0097] The number of screw holes 224 and through holes 226 provided is the same as the number of screws 222. In this embodiment, two screw holes 224 are provided. Two through holes 226 are provided. The screw holes 224 are provided at positions opposing each other across the rotation axis AX. The through holes 226 are provided at positions opposing each other across the rotation axis AX.

[0098] In this embodiment, the electric fastening machine 1 includes a cover member 100 that covers the screw 222 from the radially outer side. The cover member 100 prevents the screw 222 from falling off the outer intermediate sleeve 200. For example, the screw 222 that fastens the outer intermediate sleeve 200 and the outer sleeve 204 may loosen due to vibration caused by the fastening operation. If the loosened screw 222 falls off the electric fastening machine 1, the screw 222 may be lost. The cover member 100 prevents the screw 222 from falling off the electric fastening machine 1.

[0099] The cover member 100 is attached to the outer intermediate sleeve 200. The cover member 100 is in the shape of a strip arranged on a part of the periphery of the outer intermediate sleeve 200. In this embodiment, the cover member 100 is made of a strip-shaped thin metal plate.

[0100] The cover member 100 generates an elastic force so as to fasten the outer intermediate sleeve 200. The cover member 100 is in the shape of a leaf spring. By the cover member 100 generating an elastic force so as to fasten the outer intermediate sleeve 200, the cover member 100 is prevented from falling off the outer intermediate sleeve 200.

[0101] The cover member 100 has a protrusion 101 that protrudes radially inward, and an opening 102. The protrusion 101 is provided in a non-opening portion of the cover member 100 where no opening 102 is provided. The protrusions 101 and openings 102 are provided in the same numbers as the screw holes 224. In this embodiment, two protrusions 101 are provided. Two openings 102 are provided. One protrusion 101 and one opening 102 are provided adjacent to each other in the circumferential direction.

[0102] In this embodiment, covering the screws 222 from the radially outer side with the cover member 100 includes blocking the screw holes 224 with the cover member 100 in a state in which the cover member 100 is attached to the outer intermediate sleeve 200 .

[0103] The cover member 100 is movable in the circumferential direction of the outer intermediate sleeve 200. The cover member 100 is supported by the outer intermediate sleeve 200 so as to be movable in the circumferential direction. When attached to the outer intermediate sleeve 200, the cover member 100 is movable between a position that covers the screw holes 224 and a position that exposes the screw holes 224.

[0104] Fig. 9 is a perspective view from the front left showing the front end of the electric fastening machine 1 according to this embodiment. Fig. 10 is a right side view showing the front end of the electric fastening machine 1 according to this embodiment. Fig. 11 is a cross-sectional view showing the front end of the electric fastening machine 1 according to this embodiment, and corresponds to the cross-sectional arrow view taken along line A2-A2 in Fig. 10.

[0105] 5, 7, and 8 show a state in which the cover member 100 is disposed in a position that covers the screw holes 224. Figures 9, 10, and 11 show a state in which the cover member 100 is disposed in a position that exposes the screw holes 224.

[0106] 5, 7, and 8, the position at which the screw hole 224 is blocked is a position at which the non-opening portion of the cover member 100 coincides with the screw hole 224. In this embodiment, the position at which the screw hole 224 is blocked is a position at which the protruding portion 101 coincides with the screw hole 224. In other words, blocking the screw hole 224 with the cover member 100 includes disposing the protruding portion 101 in the screw hole 224.

[0107] 8, the protrusion 101 enters the screw hole 224 from the radially outer opening of the screw hole 224. The protrusion 101 can come into contact with the edge of the outer intermediate sleeve 200 that defines the radially outer opening of the screw hole 224.

[0108] As shown in FIGS. 9, 10, and 11, the position at which the screw hole 224 is exposed is the position at which the opening 102 coincides with the screw hole 224.

[0109] For example, when performing a tightening operation between a torsion bolt and a nut, the worker places the cover member 100 in a position that covers the screw hole 224, as shown in Figures 5, 7, and 8. Since the screw hole 224 is covered from the radial outside by the cover member 100, the screw 222 is prevented from falling off. Since the outer intermediate sleeve 200 is tightened to the cover member 100 by the elastic force of the cover member 100, unnecessary movement of the cover member 100 during the tightening operation is prevented.

[0110] For example, when replacing the outer sleeve 204, the worker places the cover member 100 in a position that exposes the screw hole 224, as shown in Figs. 9, 10, and 11. The worker rotates the cover member 100 by hand while the cover member 100 is attached to the outer intermediate sleeve 200. The worker rotates the cover member 100 by twisting it so that the opening 102 and the screw hole 224 match. The cover member 100 is placed in a position that exposes the screw hole 224 by rotating it around the outer intermediate sleeve 200 so that the opening 102 and the screw hole 224 match. The worker can bring a tool into contact with the screw 222 through the opening 102 and remove the screw 222. The outer sleeve 204 is removed from the outer intermediate sleeve 200 by releasing the fixation between the outer intermediate sleeve 200 and the outer sleeve 204 by the screw 222. When fixing the outer sleeve 204 to the outer intermediate sleeve 200, an operator inserts the rear end of the outer sleeve 204 radially inside the front end of the outer intermediate sleeve 200, and then inserts the screw 222 into the screw hole 224 and the through hole 226 through the opening 102. After inserting the screw 222 into the screw hole 224 and the through hole 226, an operator brings a tool into contact with the screw 222 through the opening 102 and tightens the screw 222. As a result, the outer intermediate sleeve 200 and the outer sleeve 204 are fixed together by the screw 222. After the outer intermediate sleeve 200 and the outer sleeve 204 are fixed together by the screw 222, the cover member 100 is rotated so that the protruding portion 101 coincides with the screw hole 224, and the screw 222 is covered by the cover member 100.

[0111] <Effects> As described above, in this embodiment, the electric tightening machine 1 includes the motor 11, the planetary gear mechanism 14 including the internal gear 31 to which the rotational force of the motor 11 is input, the outer intermediate sleeve 200 arranged radially inside the front end of the internal gear 31 and to which the rotational force of the planetary gear mechanism 14 is input, the inner intermediate sleeve 202 arranged radially inside the outer intermediate sleeve 200 and to which the rotational force of the planetary gear mechanism 14 is input, the outer sleeve 204 arranged radially inside the front end of the outer intermediate sleeve 200 and holding a nut, the inner sleeve 206 arranged radially inside the outer sleeve 204 and holding a pintail of a shear bolt, and the screw 222 that fixes the outer intermediate sleeve 200 and the outer sleeve 204. The electric tightening machine 1 includes a cover member 100 that covers the screw 222 from the radial outside.

[0112] In the above configuration, the cover member 100 is provided to cover the screw 222, so that even if the screw 222 becomes loose, the cover member 100 prevents the screw 222 from falling off.

[0113] In this embodiment, the cover member 100 is attached to an outer intermediate sleeve 200 .

[0114] In the above configuration, an operator can, for example, replace the outer sleeve 204 while the cover member 100 is attached to the outer intermediate sleeve 200. This reduces the risk of the cover member 100 being lost.

[0115] In this embodiment, the outer intermediate sleeve 200 has a screw hole 224 to which the screw 222 is coupled. The outer sleeve 204 has a through hole 226 to which the tip of the screw 222 is inserted. The cover member 100, when attached to the outer intermediate sleeve 200, is movable between a position that covers the screw hole 224 and a position that exposes the screw hole 224.

[0116] In the above configuration, the worker can perform a tightening operation using the electric tightening tool 1 with the cover member 100 placed in a position that covers the screw holes 224. The worker can perform, for example, a replacement operation of the outer sleeve 204 with the cover member 100 placed in a position that exposes the screw holes 224.

[0117] In this embodiment, the cover member 100 is movable in the circumferential direction of the outer intermediate sleeve 200 .

[0118] In the above configuration, an operator can move the cover member 100 in the circumferential direction to move the cover member 100 between a position that covers the screw holes 224 and a position that exposes the screw holes 224.

[0119] In this embodiment, the cover member 100 is in the form of a strip that is disposed around a portion of the periphery of the outer intermediate sleeve 200 .

[0120] In the above configuration, the shape or structure of the cover member 100 is prevented from becoming complicated.

[0121] In this embodiment, the cover member 100 generates an elastic force to tighten the outer intermediate sleeve 200 .

[0122] In the above configuration, the elastic force of the cover member 100 prevents the cover member 100 from moving unnecessarily or from falling off the outer intermediate sleeve 200. When the cover member 100 is attached to the outer intermediate sleeve 200, the cover member 100 can be attached to the outer intermediate sleeve 200 by expanding the diameter of the cover member 100 against the elastic force of the cover member 100.

[0123] In this embodiment, the cover member 100 has an opening 102. The position at which the screw hole 224 is covered is a position at which the non-opening portion of the cover member 100 coincides with the screw hole 224. The position at which the screw hole 224 is exposed is a position at which the opening 102 coincides with the screw hole 224.

[0124] In the above configuration, an opening 102 is provided in a portion of the cover member 100, so that an operator can expose the screw hole 224 by moving the cover member 100 circumferentially so that the opening 102 aligns with the screw hole 224.

[0125] In this embodiment, the cover member 100 has a protruding portion 101 that protrudes radially inward. The position at which the screw hole 224 is covered is the position at which the protruding portion 101 coincides with the screw hole 224.

[0126] In the above configuration, a protrusion 101 is provided in a portion of the non-opening part of the cover member 100, so that an operator can cover the screw hole 224 by moving the cover member 100 circumferentially so that the protrusion 101 aligns with the screw hole 224.

[0127] In this embodiment, the protrusion 101 is contactable with an edge of the outer intermediate sleeve 200 that defines the radially outer opening of the screw hole 224 .

[0128] In the above configuration, the protrusion 101 contacts the edge of the outer intermediate sleeve 200 with the position of the protrusion 101 coinciding with the position of the screw hole 224, so that the cover member 100 is positioned relative to the outer intermediate sleeve 200. This prevents the cover member 100 from moving unnecessarily during a fastening operation using the electric fastening machine 1, for example.

[0129] [Second embodiment] A second embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0130] <Cover material> Fig. 12 is a perspective view from the left front showing the front end of the electric fastening machine 1 according to this embodiment. Fig. 13 is an exploded perspective view from the left front showing the front end of the electric fastening machine 1 according to this embodiment. Fig. 14 is a right side view showing the front end of the electric fastening machine 1 according to this embodiment. Fig. 15 is a cross-sectional view showing the front end of the electric fastening machine 1 according to this embodiment. Fig. 16 is a cross-sectional view showing the front end of the electric fastening machine 1 according to this embodiment.

[0131] In this embodiment, the cover member 300 that covers the screws 222 from the radially outer side is movable in the axial direction of the outer intermediate sleeve 200. Similar to the cover member 100 described in the above-mentioned first embodiment, the cover member 300 is attached to the outer intermediate sleeve 200. When attached to the outer intermediate sleeve 200, the cover member 300 is movable between a position that covers the screw holes 224 and a position that exposes the screw holes 224.

[0132] 12, 14, and 15 show a state in which the cover member 100 is disposed in a position that covers the screw holes 224. Fig. 16 shows a state in which the cover member 100 is disposed in a position that exposes the screw holes 224.

[0133] The cover member 300 is annular and disposed around the outer intermediate sleeve 200. As shown in Fig. 13, in this embodiment, the cover member 300 includes an arc-shaped first cover member 300L and an arc-shaped second cover member 300R fixed to the first cover member 300L. That is, in this embodiment, the cover member 300 has a so-called half-split structure.

[0134] A first protrusion 300C provided at one end (upper end) of the first cover member 300L is press-fitted into a first recess 300D provided at one end (upper end) of the second cover member 300R. A second protrusion 300C provided at the other end (lower end) of the second cover member 300R is press-fitted into a second recess (not shown in FIG. 13) provided at the other end (lower end) of the first cover member 300L, thereby fixing the first cover member 300L and the second cover member 300R.

[0135] The cover member 300 is movable in the axial direction (front-rear direction) of the outer intermediate sleeve 200. The cover member 300 is supported by the outer intermediate sleeve 200 so as to be movable in the axial direction. When attached to the outer intermediate sleeve 200, the cover member 300 is movable between a position that covers the screw holes 224 and a position that exposes the screw holes 224.

[0136] 16, in this embodiment, the position at which the screw holes 224 are exposed is a position at which the cover member 300 is disposed rearward of the screw holes 224. That is, the screw holes 224 are exposed by the cover member 300 moving to the rear end of the movable range of the cover member 300 in the front-rear direction.

[0137] In this embodiment, a spring 301 is provided that generates an elastic force so that the cover member 300 moves to a position where it covers the screw hole 224. The spring 301 is a compression coil spring. The screw hole 224 is covered by the cover member 300 moving to the front end of the movable range of the cover member 300 in the front-rear direction. The spring 301 generates an elastic force so that the cover member 300 moves to the front end of the movable range of the cover member 300 in the front-rear direction.

[0138] The cover member 300 is made of synthetic resin. The cover member 300 may be made of metal. The cover member 300 has a ring portion 300A and a stopper portion 300B protruding radially inward from the ring portion 300A. The ring portion 300A is a belt-like shape that surrounds the outer intermediate sleeve 200. The stopper portion 300B protrudes radially inward from the inner peripheral surface of the ring portion 300A. The stopper portion 300B is provided so as to surround the outer intermediate sleeve 200. The stopper portion 300B is provided at the middle portion of the inner peripheral surface of the ring portion 300A in the front-rear direction. The front end portion of the ring portion 300A protrudes forward from the stopper portion 300B.

[0139] The outer intermediate sleeve 200 has a large diameter portion 200D in which a screw hole 224 is provided, and a small diameter portion 200C provided rearward of the large diameter portion 200D. The spring 301 is disposed around the small diameter portion 200C. The stopper portion 300B is disposed around the small diameter portion 200C. The stopper portion 300B moves in the front-rear direction around the small diameter portion 200C. The front end portion of the ring portion 300A is movable between a position that covers the screw hole 224 and a position that exposes the screw hole 224.

[0140] The front end of the spring 301 contacts the rear surface 300F of the stopper portion 300B. The rear end of the spring 301 contacts the rear support surface 200B provided at the rear end of the small diameter portion 200C. The rear support surface 200B faces forward.

[0141] As shown in FIG. 15, with the ring portion 300A disposed in a position to cover the screw hole 224, the front surface 300E of the stopper portion 300B comes into contact with the front support surface 200A provided at the front end portion of the small diameter portion 200C.

[0142] The front support surface 200A faces substantially rearward. The front support surface 200A is inclined forward and radially outward. The front surface 300E of the stopper portion 300B is parallel to the front support surface 200A.

[0143] As shown in FIG. 15, when the ring portion 300A is disposed in a position to cover the screw hole 224, the front end of the ring portion 300A and the front end of the screw hole 224 coincide with each other.

[0144] For example, when performing a tightening operation of a torsion bolt and a nut, the worker places the cover member 300 in a position to cover the screw hole 224, as shown in Figures 12, 14, and 15. Since the screw hole 224 is covered from the radial outside by the cover member 300, the screw 222 is prevented from falling off. Since the stopper portion 300B of the cover member 300 is pressed against the front support surface 200A of the outer intermediate sleeve 200 by the elastic force of the spring 301, unnecessary movement of the cover member 300 during the tightening operation is prevented.

[0145] For example, when replacing the outer sleeve 204, the worker places the cover member 300 in a position where the screw hole 224 is exposed, as shown in FIG. 16. With the cover member 300 attached to the outer intermediate sleeve 200, the worker manually moves the cover member 300 backward so that the cover member 300 moves from a position where the cover member 300 covers the screw hole 224 to a position where the cover member 300 exposes the screw hole 224. The worker can remove the screw 222 by bringing a tool into contact with the screw 222 through the opening 102. The outer sleeve 204 is removed from the outer intermediate sleeve 200 by releasing the fixation between the outer intermediate sleeve 200 and the outer sleeve 204 by the screw 222. When fixing the outer sleeve 204 to the outer intermediate sleeve 200, the worker inserts the rear end of the outer sleeve 204 radially inside the front end of the outer intermediate sleeve 200, and then inserts the screw 222 into the screw hole 224 and the through hole 226 through the opening 102. After inserting the screw 222 into the screw hole 224 and the through hole 226, the worker brings a tool into contact with the screw 222 through the opening 102 and tightens the screw 222. This causes the outer intermediate sleeve 200 and the outer sleeve 204 to be fixed together by the screw 222. After the outer intermediate sleeve 200 and the outer sleeve 204 are fixed together by the screw 222, the cover member 300 moves forward due to the elastic force of the spring 301, so that the screw 222 is covered by the cover member 300.

[0146] <Effects> As described above, in this embodiment, the cover member 300 is movable in the axial direction of the outer intermediate sleeve 200.

[0147] In the above configuration, an operator can move the cover member 300 in the axial direction to move the cover member 300 between a position that covers the screw hole 224 and a position that exposes the screw hole 224.

[0148] In this embodiment, the cover member 300 is annular and disposed around the outer intermediate sleeve 200 .

[0149] In the above configuration, since the cover member 300 is provided so as to surround the outer intermediate sleeve 200, the cover member 300 is prevented from falling off the outer intermediate sleeve 200.

[0150] In this embodiment, the cover member 300 includes a circular arc-shaped first cover member 300L and a circular arc-shaped second cover member 300R fixed to the first cover member 300L.

[0151] In the above configuration, since the cover member 300 has a so-called half-split structure, the cover member 300 can be disposed around the outer intermediate sleeve 200 .

[0152] In this embodiment, a first convex portion 300C provided at one end of the first cover member 300L is pressed into a first recess 300D provided at one end of the second cover member 300R, and a second convex portion 300C provided at the other end of the second cover member 300R is pressed into a second recess 300D provided at the other end of the first cover member 300L, thereby fixing the first cover member 300L and the second cover member 300R.

[0153] In the above configuration, the first cover member 300L and the second cover member 300R are fixed together without using, for example, an adhesive.

[0154] In this embodiment, the position at which the screw hole 224 is exposed is a position at which the cover member 300 is disposed rearward of the screw hole 224 .

[0155] In the above configuration, an operator can move the cover member 300, which is disposed in a position covering the screw hole 224, backward, thereby moving the cover member 300 from a position covering the screw hole 224 to a position exposing the screw hole 224.

[0156] In this embodiment, the electric fastener 1 includes a spring 301 that generates an elastic force so that the cover member 300 moves to a position where it covers the screw hole 224 .

[0157] In the above configuration, the elastic force of the spring 301 enables the cover member 300 to move from a position where the screw hole 224 is exposed to a position where the screw hole 224 is covered.

[0158] In this embodiment, the cover member 300 has a ring portion 300A and a stopper portion 300B protruding radially inward from the ring portion 300A. The outer intermediate sleeve 200 has a large diameter portion 200D in which a screw hole 224 is provided, and a small diameter portion 200C provided rearward of the large diameter portion 200D. The spring 301 and the stopper portion 300B are disposed around the small diameter portion 200C.

[0159] In the above configuration, the ring portion 300A can be disposed around the large diameter portion 200D.

[0160] In this embodiment, the front end of the spring 301 contacts the rear surface 300F of the stopper portion 300B, and the rear end of the spring 301 contacts the rear support surface 200B provided at the rear end of the small diameter portion 200C.

[0161] In the above configuration, the spring 301 can generate an elastic force so that the ring portion 300A moves from a position where the screw hole 224 is exposed to a position where the screw hole 224 is blocked.

[0162] In this embodiment, with the ring portion 300A disposed in a position that blocks the screw hole 224, the front surface of the stopper portion 300B comes into contact with the front support surface 200A provided at the front end portion of the small diameter portion 200C.

[0163] In the above configuration, the ring portion 300A is positioned at a position that covers the screw hole 224. The elastic force of the spring 301 presses the stopper portion 300B against the front support surface 200A of the outer intermediate sleeve 200, thereby preventing the cover member 300 from moving unnecessarily.

[0164] In this embodiment, the front support surface 200A is inclined forward and radially outward.

[0165] In the above configuration, the stopper portion 300B comes into contact with the front support surface 200A that is inclined forward toward the outside in the radial direction, so that the ring portion 300A is positioned at a position where it covers the screw hole 224.

[0166] In this embodiment, when the ring portion 300A is disposed in a position that covers the screw hole 224, the front end of the ring portion 300A and the front end of the screw hole 224 coincide with each other.

[0167] The above configuration prevents the ring portion 300A from becoming too large, particularly the axial dimension of the ring portion 300A from becoming too large.

[0168] [Other embodiments] In the above embodiment, the electric tightening machine 1 is a shear wrench. The electric tightening machine 1 may be a primary tightening wrench. [Explanation of symbols]

[0169] 1...electric tightening machine, 2...housing, 4...power transmission section, 6...power section, 7...handle section, 8...battery, 9...battery mounting section, 10...rotor shaft, 11...motor, 12...intermediate gear mechanism, 14...planetary gear mechanism, 18...sleeve mechanism, 20...handle housing, 21...left handle housing, 22...right handle housing, 24...motor housing, 26...gear housing, 28...rear cover, 30...gear case, 31...internal gear, 34...screw, 35...screw, 38... Screw, 40...hole, 44...switch, 45...trigger, 56...tip lever, 74...controller, 79...vent, 80...partition rib, 90...intake port, 96...stator, 98...rotor, 100...cover member, 101...protrusion, 102...opening, 108...sensor circuit board, 115...pinion, 122...bearing, 124...bearing, 126...fan, 128...exhaust port, 130...first intermediate gear, 132...second intermediate gear, 134...bearing, 136...bearing, 138...bearing, 139...bearing, 140...rod , 150... rear planetary gear train, 151... bevel teeth, 152... planetary gear, 156... bearing, 157... bearing, 160... middle planetary gear train, 162... planetary gear, 170... front planetary gear train, 172... planetary gear, 173... pin, 174... carrier, 175... internal tooth portion, 180... tip rod, 182... extrusion ring, 200... outer intermediate sleeve, 200A... front support surface, 200B... rear support surface, 200C... small diameter portion, 200D... large diameter portion, 202... inner intermediate sleeve, 204... outer sleeve, 206... inner Reeve, 210...bearing, 211...bearing, 212...inner sleeve spring, 214...pin, 216...stopper, 218...head, 220...tip rod spring, 222...screw, 224...screw hole, 226...through hole, 230...claw portion, 232...groove portion, 300...cover member, 300A...ring portion, 300B...stopper portion, 300C...convex portion, 300D...concave portion, 300E...front surface, 300F...rear surface, 300L...first cover member, 300R...second cover member, 301...spring, AX...rotating shaft.

Claims

1. A motor; a planetary gear mechanism including an internal gear to which the rotational force of the motor is input; an outer intermediate sleeve disposed radially inside a front end portion of the internal gear, to which a rotational force of the planetary gear mechanism is input; an inner intermediate sleeve disposed radially inside the outer intermediate sleeve and receiving a rotational force of the planetary gear mechanism; an outer sleeve disposed radially inside a front end portion of the outer intermediate sleeve and holding a nut; an inner sleeve disposed radially inside the outer sleeve and holding a pin tail of a shear bolt; a screw for fixing the outer intermediate sleeve and the outer sleeve together; A cover member that covers the screw from the radially outer side. Electric clamping machine.

2. The cover member is attached to the outer intermediate sleeve. The electric fastening machine according to claim 1.

3. the outer intermediate sleeve has a screw hole into which the screw is coupled; the outer sleeve has a through hole into which the tip of the screw is inserted, The cover member is movable between a position that covers the screw holes and a position that exposes the screw holes when attached to the outer intermediate sleeve. The electric fastening machine according to claim 1.

4. The cover member is movable in the circumferential direction of the outer intermediate sleeve. The electric fastening machine according to claim 3.

5. The cover member is a strip-shaped member that is disposed around a portion of the outer intermediate sleeve. The electric fastening machine according to claim 4.

6. The cover member generates an elastic force to tighten the outer intermediate sleeve. The electric fastening machine according to claim 5.

7. The cover member has an opening, the position at which the screw hole is covered is a position at which the non-opening portion of the cover member coincides with the screw hole; The position where the screw hole is exposed is a position where the opening coincides with the screw hole. The electric fastening machine according to claim 4.

8. the cover member has a protruding portion that protrudes radially inward, The position at which the screw hole is blocked is a position at which the protrusion coincides with the screw hole. The electric fastening machine according to claim 3.

9. the protrusion is capable of contacting an edge of the outer intermediate sleeve that defines a radially outer opening of the screw hole; The electric fastening machine according to claim 8.

10. The cover member is movable in the axial direction of the outer intermediate sleeve. The electric fastening machine according to claim 3.

11. The cover member has an annular shape and is disposed around the outer intermediate sleeve. The electric fastening machine according to claim 10.

12. The cover member includes an arc-shaped first cover member and an arc-shaped second cover member fixed to the first cover member. The electric fastening machine according to claim 11.

13. a first protrusion provided at one end of the first cover member is press-fitted into a first recess provided at one end of the second cover member; a second protrusion provided at the other end of the second cover member is press-fitted into a second recess provided at the other end of the first cover member, thereby fixing the first cover member and the second cover member together; The electric fastening machine according to claim 12.

14. The position at which the screw hole is exposed is a position at which the cover member is disposed rearward of the screw hole. The electric fastening machine according to claim 10.

15. a spring that generates an elastic force so that the cover member moves to a position where it covers the screw hole; The electric fastening machine according to claim 14.

16. The cover member has a ring portion and a stopper portion protruding radially inward from the ring portion, the outer intermediate sleeve has a large diameter portion in which the screw hole is provided and a small diameter portion provided rearward of the large diameter portion, the spring and the stopper portion are disposed around the small diameter portion; The electric fastening machine according to claim 15.

17. a front end of the spring contacts a rear surface of the stopper portion, and a rear end of the spring contacts a rear support surface provided at a rear end of the small diameter portion; The electric fastening machine according to claim 16.

18. When the ring portion is disposed at a position where it covers the screw hole, a front surface of the stopper portion contacts a front support surface provided at a front end of the small diameter portion. The electric fastening machine according to claim 16.

19. The front support surface is inclined forward and radially outward. The electric fastening machine according to claim 18.

20. When the ring portion is disposed at a position where it covers the screw hole, a front end of the ring portion and a front end of the screw hole are aligned. The electric fastening machine according to claim 18.

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