Power tool

Abstract

To provide a power tool which can suppress leakage of grease within a casing to the outside.SOLUTION: A power tool includes: a motor; a planetary gear which is driven by the motor; an internal gear which is engaged with the planetary gear; a casing which stores the planetary gear and the internal gear; a through hole which is provided on each of one side and the other side of a lateral side with respect to an axial direction of a central axis of the internal gear of the casing; a link which is inserted into each through hole and makes the internal gear movable in the axial direction; and a cover member which covers a gap between the through hole and the link.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The technology disclosed in this specification relates to power tools. [Background technology]

[0002] In the technical field of power tools, there is known a driver drill in which the speed mode of a planetary gear can be switched between a high-speed mode and a low-speed mode, as disclosed in Patent Document 1. In such a driver drill, the speed mode can be switched by moving a speed switching lever. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] China Patent Publication No. 102049549 Summary of the Invention [Problem to be solved by the invention]

[0004] In the driver drill, the planetary gear is housed in a casing. A switching wire is connected to the speed switching lever. The switching wire is inserted from the outside to the inside of the casing and connected to the planetary gear. An insertion hole for inserting the switching wire is provided in the casing. In order to move the switching wire, the insertion hole is formed along the moving direction of the switching wire. In such a configuration, it is necessary to suppress leakage of grease inside the casing to the outside. [Means for solving the problem]

[0005] This specification discloses an electric power tool including a motor, a planetary gear driven by the motor, an internal gear meshing with the planetary gear, a casing accommodating the planetary gear and the internal gear, through holes provided on one and the other sides of the casing in an axial direction of a central axis of the internal gear, links inserted into the respective through holes to move the internal gear in the axial direction, and a cover member covering a gap between the through holes and the links.

[0006] This specification discloses an electric power tool that includes a motor, a planetary gear disposed in front of the motor and driven by the motor, an internal gear meshing with the planetary gear, a casing that houses the planetary gear and the internal gear, an output section disposed in front of the planetary gear and driven by the planetary gear, a right through groove provided in a right part of the casing and extending in a front-rear direction, a left through groove provided in a left part of the casing and extending in a front-rear direction, a right link inserted in the right through groove and capable of moving the internal gear in the front-rear direction, a left link inserted in the left through groove and capable of moving the internal gear in the front-rear direction, a right cover member that covers a gap between the right through groove and the right link, and a left cover member that covers a gap between the left through groove and the left link. Effect of the Invention

[0007] The technology disclosed in this specification provides a power tool that can prevent grease inside a casing from leaking to the outside. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a front perspective view showing a driver drill according to an embodiment. [Diagram 2] FIG. 2 is a side view showing the driver drill according to the embodiment. [Diagram 3] FIG. 3 is a cross-sectional view showing a driver drill according to an embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing an upper portion of the driver drill according to the embodiment. [Diagram 5] FIG. 5 is a perspective view showing a casing and a link according to the embodiment. [Figure 6] FIG. 6 is an exploded perspective view showing a casing and a link according to the embodiment. [Figure 7] FIG. 7 is a side view showing a casing and a link according to the embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing a casing and a link according to the embodiment. [Figure 9] FIG. 9 is a perspective view showing a first casing and a link according to the embodiment. [Figure 10] FIG. 10 is a cross-sectional view showing a first casing and a link according to the embodiment. [Figure 11] FIG. 11 is a perspective view showing a casing and a link according to the embodiment. [Figure 12] FIG. 12 is an exploded perspective view showing a casing and a link according to the embodiment. [Figure 13] FIG. 13 is a side view showing a casing and a link according to the embodiment. [Figure 14] FIG. 14 is a cross-sectional view showing a casing and a link according to the embodiment. [Figure 15] FIG. 15 is a cross-sectional view showing a first casing and a link according to the embodiment. [Figure 16] FIG. 16 is a perspective view showing a casing and a link according to the embodiment. [Figure 17] FIG. 17 is an exploded perspective view showing a casing and a link according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In one or more embodiments, the power tool may include a motor, a planetary gear driven by the motor, an internal gear that meshes with the planetary gear, a casing that houses the planetary gear and the internal gear, through holes provided on one and the other lateral sides of the casing relative to the axial direction of a central axis of the internal gear, links inserted into each of the through holes to move the internal gear in the axial direction, and a cover member that covers a gap between the through holes and the links.

[0010] In the above-described configuration, the gap between the through hole of the casing and the link is covered with the cover member, which makes it possible to prevent the grease inside the casing from leaking to the outside.

[0011] In one or more embodiments, the cover member may be provided to be movable in conjunction with the movement of the link.

[0012] In the above configuration, since the cover member is movable in conjunction with the movement of the link, it is possible to cover the gap without interfering with the movement of the link.

[0013] In one or more embodiments, the cover member is configured to maintain the gap covered throughout its range of movement in response to movement of the link.

[0014] In the above configuration, the cover member maintains the state in which the gap is covered over the entire range of movement, so that leakage of grease inside the casing to the outside can be more appropriately prevented.

[0015] In one or more embodiments, the cover member has a tapered shape at least on one end in the direction of movement.

[0016] In the above configuration, at least one end of the cover member in the movement direction has a tapered shape, so that the cover member can easily push aside the grease when it moves.

[0017] In one or more embodiments, the cover member may be axially movable.

[0018] In the above configuration, in a configuration in which the cover member is provided so as to be movable in the axial direction, leakage of grease inside the casing to the outside can be suppressed.

[0019] In one or more embodiments, the cover member may be movable transversely axially along a surface of the casing.

[0020] In the above configuration, in a configuration in which the cover member is provided movably in a direction intersecting the axial direction along the surface of the casing, leakage of grease inside the casing to the outside can be suppressed.

[0021] In one or more embodiments, the cover member may have a groove extending in a direction oblique to the axial direction.

[0022] In the above configuration, the cover member has a cover side through hole extending in a direction inclined relative to the axial direction, so that when the link moves in the axial direction, the cover member can be appropriately moved in a direction intersecting the axial direction depending on the inclination of the cover side through hole.

[0023] In one or more embodiments, the casing may have a guide portion for guiding the cover member.

[0024] In the above-described configuration, since the casing has a guide portion that guides the cover member, the cover member can be moved smoothly in conjunction with the movement of the link.

[0025] In one or more embodiments, the guide portions may be disposed on both sides of the cover member in the direction of movement.

[0026] In the above configuration, since the guide portions are disposed on both sides in the moving direction of the cover member, the cover member can be guided more appropriately.

[0027] In one or more embodiments, the casing may have a fall-off prevention portion that prevents the cover member from falling off the guide portion.

[0028] In the above configuration, the anti-fall-out portion prevents the cover member from falling off from the guide portion, thereby allowing the cover member to move smoothly while appropriately preventing grease inside the casing from leaking to the outside.

[0029] In one or more embodiments, the fall-off prevention portion may be provided so as to surround the cover member between the fall-off prevention portion and the guide portion.

[0030] In the above configuration, the fall-off prevention portion is provided so as to surround the cover member between itself and the guide portion, so that the cover member can be appropriately prevented from falling off.

[0031] In one or more embodiments, the casing may have a stopper disposed at an end in the direction of movement of the cover member.

[0032] In the above-described configuration, since the stopper is provided at the end of the casing in the moving direction of the cover member, the cover member can be appropriately positioned.

[0033] In one or more embodiments, the cover member may have a shape that protrudes laterally in the direction of movement, and the stopper may be disposed at a position that abuts against the protruding portion of the cover member.

[0034] In the above configuration, the cover member has a shape that protrudes laterally in the direction of movement, and the stopper is positioned at a position where it abuts the protruding portion of the cover member, so that the cover member can be properly positioned by abutting the protruding portion of the cover member against the stopper.

[0035] In one or more embodiments, the cover member may be disposed within the casing.

[0036] In the above-described configuration, since the cover member is disposed inside the casing, it is possible to cover the gap from the inside of the through hole, thereby appropriately preventing the grease inside the casing from leaking to the outside.

[0037] In one or more embodiments, the cover member may be disposed externally of the casing.

[0038] In the above-described configuration, since the cover member is disposed outside the casing, it is possible to cover the gap from the outside of the through hole, thereby appropriately preventing the grease inside the casing from leaking to the outside.

[0039] In one or more embodiments, the cover member may be formed using an elastic material that deforms in response to movement of the link.

[0040] In the above-described configuration, since the cover member is formed using an elastic body that deforms in response to movement of the link, it is possible to cover the gap without interfering with movement of the link.

[0041] In one or more embodiments, the cover member may have an axially extending cover-side through hole, the cover-side through hole having a width smaller than a diameter of the link.

[0042] In the above configuration, the cover member has a cover-side through hole extending in the axial direction, and the width of the cover-side through hole is smaller than the diameter of the link, so that by inserting the link into the cover-side through hole, the cover-side through hole elastically deforms so as to expand at the portion where the link is inserted. The portion of the cover-side through hole other than the inserted portion remains in a state where it does not expand in the vertical direction. When the link moves, the cover member elastically deforms in accordance with the movement of the link, and the position where it expands in the vertical direction changes. Therefore, when the link is inserted, the cover member can appropriately cover the area between the through hole and the link.

[0043] In one or more embodiments, the cover-side through-hole may include a linear cut portion.

[0044] In the above configuration, since the cover-side through hole includes a linear cut portion, the area between the through hole and the link can be appropriately covered in the area other than the insertion portion of the link.

[0045] In one or more embodiments, the cover member may be formed using a porous material.

[0046] In the above configuration, the cover member is made of a porous material and is therefore capable of absorbing grease.

[0047] In one or more embodiments, the power tool may include a motor, a planetary gear disposed in front of the motor and driven by the motor, an internal gear that meshes with the planetary gear, a casing that houses the planetary gear and the internal gear, an output section disposed in front of the planetary gear and driven by the planetary gear, a right through groove provided in a right part of the casing and extending in the front-to-rear direction, a left through groove provided in a left part of the casing and extending in the front-to-rear direction, a right link inserted into the right through groove and capable of moving the internal gear in the front-to-rear direction, a left link inserted into the left through groove and capable of moving the internal gear in the front-to-rear direction, a right cover member that covers a gap between the right through groove and the right link, and a left cover member that covers a gap between the left through groove and the left link.

[0048] With the above configuration, in a power tool having an output part driven by a planetary gear, leakage of grease inside the casing to the outside can be appropriately suppressed.

[0049] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited thereto. The components of the embodiments described below can be appropriately combined. In addition, some components may not be used.

[0050] In the embodiments, the positional relationship of each part will be described using the terms left, right, front, rear, top, and bottom. These terms indicate a relative position or direction based on the center of the power tool.

[0051] The electric power tool has a motor. In the embodiments, a direction parallel to a rotation axis AX of the motor is referred to as an axial direction, a direction going around the rotation axis AX is referred to as a circumferential direction or a rotation direction, and a radial direction of the rotation axis AX is referred to as a radial direction.

[0052] In the embodiment, the rotation axis AX extends in the front-rear direction. The axial direction and the front-rear direction coincide with each other. One axial side is the front, and the other axial side is the rear. In addition, in the radial direction, a position closer to or a direction approaching the rotation axis AX is appropriately referred to as the radial inner side, and a position farther from or a direction away from the rotation axis AX is appropriately referred to as the radial outer side.

[0053] In the embodiment, the power tool is a driver drill, which is a type of screw tightening tool. The power tool will be referred to as a driver drill as appropriate.

[0054] [Driver Drill Overview] Fig. 1 is a front perspective view showing the driver drill 1 according to the embodiment. Fig. 2 is a side view showing the driver drill 1 according to the embodiment. Fig. 3 is a cross-sectional view showing the driver drill 1 according to the embodiment. In the embodiment, the driver drill 1 is a vibration driver drill.

[0055] As shown in Figures 1, 2, and 3, the driver drill 1 includes a housing 2, a rear cover 3, a casing 4, a battery mounting section 5, a motor 6, a power transmission mechanism 7, an output section 8, a fan 9, a trigger lever 10, a forward / reverse rotation switch lever 11, a speed switch lever 12, a mode switch ring 13, a light unit 14, an interface panel 15, a dial 16, and a controller 18.

[0056] The housing 2 is made of synthetic resin. In this embodiment, the housing 2 is made of nylon. The housing 2 includes a left housing 2L and a right housing 2R. The left housing 2L and the right housing 2R are fixed together by a screw 2S. The housing 2 is formed by fixing the left housing 2L and the right housing 2R together.

[0057] The housing 2 has a motor accommodating portion 21, a grip portion 22, a battery holding portion 23, and a light holding portion 24.

[0058] The motor accommodating portion 21 accommodates the motor 6. The motor accommodating portion 21 is cylindrical.

[0059] The grip portion 22 is held by an operator. The grip portion 22 is disposed below the motor accommodating portion 21. The grip portion 22 extends downward from the motor accommodating portion 21. The trigger lever 10 is disposed in front of the grip portion 22.

[0060] The battery holding section 23 houses the controller 18. The battery holding section 23 holds the battery 20 via the battery attachment section 5. The battery holding section 23 is disposed below the grip section 22. The battery holding section 23 is connected to the lower end of the grip section 22. The external dimensions of the battery holding section 23 are larger than the external dimensions of the grip section 22 in both the front-rear and left-right directions.

[0061] The light holding portion 24 holds the light unit 14. The light holding portion 24 is fixed to the front of the battery holding portion 23 with a screw 5S. The light holding portion 24 may be considered as a part of the battery holding portion 23. The battery holding portion 23 may be considered as a first battery holding portion, and the light holding portion 24 may be considered as a second battery holding portion.

[0062] The rear cover 3 is made of synthetic resin. The rear cover 3 is disposed behind the motor accommodating portion 21. The rear cover 3 accommodates the fan 9. The rear cover 3 is disposed so as to cover an opening at the rear of the motor accommodating portion 21. The rear cover 3 is fixed to the motor accommodating portion 21 with screws 3S.

[0063] The motor accommodating portion 21 has an intake port 19A. The rear cover 3 has an exhaust port 19B. Air in the external space of the housing 2 flows into the internal space of the housing 2 through the intake port 19A. Air in the internal space of the housing 2 flows out to the external space of the housing 2 through the exhaust port 19B.

[0064] The casing 4 houses the power transmission mechanism 7. The casing 4 includes a first casing 4A and a second casing 4B. The second casing 4B is disposed in front of the first casing 4A. The mode switching ring 13 is disposed in front of the second casing 4B. The first casing 4A and the second casing 4B are made of synthetic resin. The casing 4 is disposed in front of the motor accommodating section 21. Each of the first casing 4A and the second casing 4B is cylindrical.

[0065] The first casing 4A is fixed to the rear end of the second casing 4B. The opening at the rear end of the first casing 4A is covered by a bracket plate 4C. The opening at the front end of the second casing 4B is covered by a stop plate 4D. The stop plate 4D is fixed to the front end of the second casing 4B by screws 4E.

[0066] The casing 4 is disposed so as to cover the opening at the front of the motor accommodating portion 21. The first casing 4A is disposed inside the motor accommodating portion 21. The second casing 4B is fixed to the motor accommodating portion 21 with screws 4S.

[0067] The battery mounting section 5 is formed at the bottom of the battery holding section 23. The battery mounting section 5 is connected to the battery 20. The battery 20 is mounted to the battery mounting section 5. The battery 20 is detachable from the battery mounting section 5. The battery 20 includes a secondary battery. In the embodiment, the battery 20 includes a rechargeable lithium ion battery. When mounted to the battery mounting section 5, the battery 20 can supply power to the driver drill 1. The motor 6 is driven based on the power supplied from the battery 20. The interface panel 15 and the controller 18 operate based on the power supplied from the battery 20.

[0068] The motor 6 is a power source of the driver drill 1. The motor 6 is an inner rotor type brushless motor. The motor 6 is housed in the motor housing 21. The motor 6 has a cylindrical stator 61 and a rotor 62 disposed inside the stator 61. The rotor 62 includes a rotor shaft 63 extending in the axial direction. The rotor 62 is rotatable relative to the stator 61.

[0069] The power transmission mechanism 7 is disposed in front of the motor 6. The power transmission mechanism 7 is housed in the casing 4. The power transmission mechanism 7 connects the rotor shaft 63 and the output unit 8. The power transmission mechanism 7 transmits the power generated by the motor 6 to the output unit 8. The power transmission mechanism 7 has a plurality of gears.

[0070] The power transmission mechanism 7 includes a reduction mechanism 30 and a vibration mechanism 40 .

[0071] The reduction mechanism 30 reduces the rotation speed of the rotor shaft 63 and rotates the output section 8 at a lower rotation speed than the rotor shaft 63. In the embodiment, the reduction mechanism 30 has a first planetary gear mechanism 31, a second planetary gear mechanism 32, and a third planetary gear mechanism 33. The second planetary gear mechanism 32 is disposed in front of the first planetary gear mechanism 31. The third planetary gear mechanism 33 is disposed in front of the second planetary gear mechanism 32. The reduction mechanism 30 including the first planetary gear mechanism 31, the second planetary gear mechanism 32, and the third planetary gear mechanism 33 is disposed in front of the rotor 62. The gears of the first planetary gear mechanism 31, the second planetary gear mechanism 32, and the third planetary gear mechanism 33 are rotated by the rotor 62.

[0072] The vibration mechanism 40 vibrates the output portion 8 in the axial direction. The vibration mechanism 40 has a first cam 41, a second cam 42, and a vibration switching ring 43.

[0073] The output unit 8 (output shaft) is disposed forward of the motor 6. The output unit 8 rotates due to the rotational force of the motor 6. The output unit 8 rotates with the tool tip attached based on the rotational force transmitted from the motor 6 via the power transmission mechanism 7. The output unit 8 is disposed forward of a reduction mechanism 30 including a first planetary gear mechanism 31, a second planetary gear mechanism 32, and a third planetary gear mechanism 33, and is rotated by the reduction mechanism 30. The output unit 8 includes a spindle 81 that rotates about a rotation axis AX based on the rotational force transmitted from the motor 6, and a chuck 82 to which the tool tip is attached.

[0074] The fan 9 is disposed behind the motor 6. The fan 9 generates an airflow for cooling the motor 6. The fan 9 is fixed to at least a portion of the rotor 62. The fan 9 is fixed to a rear portion of the rotor shaft 63. The fan 9 rotates by the rotation of the rotor shaft 63. As the rotor shaft 63 rotates, the fan 9 rotates together with the rotor shaft 63. As the fan 9 rotates, air in the external space of the housing 2 flows into the internal space of the housing 2 through the intake port 19A. The air that has flowed into the internal space of the housing 2 cools the motor 6 by circulating through the internal space of the housing 2. The air that has circulated through the internal space of the housing 2 flows out to the external space of the housing 2 through the exhaust port 19B.

[0075] The trigger lever 10 is operated to start the motor 6. The trigger lever 10 is provided on the upper part of the grip portion 22. The front end of the trigger lever 10 protrudes forward from the front of the grip portion 22. The trigger lever 10 is movable in the front-rear direction. The trigger lever 10 is operated by an operator. When the trigger lever 10 is operated so as to move backward, a trigger signal is generated in the trigger signal generating circuit 17, and the motor 6 is started. When the operation of the trigger lever 10 is released, the motor 6 is stopped.

[0076] The forward / reverse switching lever 11 is operated to switch the rotation direction of the motor 6. The forward / reverse switching lever 11 is provided on the upper part of the grip portion 22. The left end of the forward / reverse switching lever 11 protrudes leftward from the left part of the grip portion 22. The right end of the forward / reverse switching lever 11 protrudes rightward from the right part of the grip portion 22. The forward / reverse switching lever 11 can move left and right. The forward / reverse switching lever 11 is operated by an operator. When the forward / reverse switching lever 11 is operated to move leftward, the motor 6 rotates in the forward direction. When the forward / reverse switching lever 11 is operated to move rightward, the motor 6 rotates in the reverse direction. When the rotation direction of the motor 6 is switched, the rotation direction of the spindle 81 is switched.

[0077] The speed switch lever 12 is operated to change the speed mode of the reduction mechanism 30. The speed switch lever 12 is provided on the upper part of the motor housing part 21. The speed switch lever 12 is movable in the forward and backward directions. The speed switch lever 12 is operated by an operator. The speed modes of the reduction mechanism 30 include a low speed mode and a high speed mode. The low speed mode refers to a speed mode in which the output part 8 is rotated at a low speed. The high speed mode refers to a speed mode in which the output part 8 is rotated at a high speed. When the speed switch lever 12 is operated to move forward, the speed mode of the reduction mechanism 30 is set to the low speed mode. When the speed switch lever 12 is operated to move backward, the speed mode of the reduction mechanism 30 is set to the high speed mode.

[0078] The mode switching ring 13 is operated to change the working mode of the vibration mechanism 40. The mode switching ring 13 is disposed in front of the casing 4. The mode switching ring 13 is rotatable. The mode switching ring 13 is operated by an operator. A mode detection ring 49 is provided which rotates integrally with the mode switching ring 13. The mode detection ring 49 is disposed inside the mode switching ring 13. A permanent magnet 49M is provided on the mode detection ring 49. The working modes of the vibration mechanism 40 include a vibration mode and a non-vibration mode. The vibration mode refers to a working mode in which the output unit 8 is vibrated in the axial direction. The non-vibration mode refers to a working mode in which the output unit 8 is not vibrated in the axial direction. The working mode of the vibration mechanism 40 is set to the vibration mode by operating the mode switching ring 13 to be disposed in the vibration mode position in the rotational direction. By manipulating the mode switching ring 13 so as to be disposed in the non-vibration mode position in the rotational direction, the working mode of the vibration mechanism 40 is set to the non-vibration mode.

[0079] The light unit 14 emits illumination light that illuminates the area in front of the driver drill 1. The light unit 14 includes, for example, a light emitting diode (LED). The light unit 14 and a light holding portion 24 that holds the light unit 14 are provided in the front of the battery holding portion 23. The light unit 14 may be considered to be disposed in the battery holding portion 23. The light unit 14 is disposed in the front of the battery holding portion 23.

[0080] A light opening 29 is provided in the light holding portion 24. The light opening 29 is formed in the front surface of the light holding portion 24 (the battery holding portion 23). At least a part of the light unit 14 is disposed in the light opening 29.

[0081] The interface panel 15 is provided in the battery holding section 23. The interface panel 15 includes an operating device 25A and a display device 25B. The interface panel 15 is plate-shaped. The operating device 25A includes an operation button. Examples of the display device 25B include a segment display including a plurality of segment light emitters, a flat panel display such as a liquid crystal display, and an indicator-type display in which a plurality of light-emitting diodes are arranged.

[0082] A panel opening 27 is formed in the battery holding portion 23. The panel opening 27 is formed in the upper surface of the battery holding portion 23, forward of the grip portion 22. At least a portion of the interface panel 15 is disposed in the panel opening 27.

[0083] The operating device 25A is operated to change the drive mode of the motor 6. The operating device 25A is operated by an operator. The drive modes of the motor 6 include a drill mode and a clutch mode. The drill mode refers to a drive mode in which the motor 6 is driven regardless of the torque acting on the motor 6 when the motor 6 is driven. The clutch mode refers to a drive mode in which the motor 6 is stopped when the torque acting on the motor 6 when the motor 6 is driven exceeds a torque threshold value.

[0084] The dial 16 is operated to change the driving conditions of the motor 6. The dial 16 is disposed on the right side of the front part of the battery holding part 23. The dial 16 is rotatable about a dial axis extending in the left-right direction. The dial 16 is rotatable 360° or more. The dial 16 is operated by an operator. The driving conditions of the motor 6 include a torque threshold. The dial 16 is operated to change the torque threshold in the clutch mode set by the operating device 25A.

[0085] A dial opening is formed in the battery holding portion 23. The dial opening is formed in the front portion of the battery holding portion 23. At least a portion of the dial 16 is disposed in the dial opening .

[0086] The controller 18 includes a computer system. The controller 18 outputs a control command to control the motor 6. At least a part of the controller 18 is housed in a controller case 26. The controller 18 is housed in a battery holding section 23 while being held in the controller case 26. The controller 18 includes a controller board 18A on which a plurality of electronic components are mounted. Examples of the electronic components mounted on the controller board 18A include a processor such as a CPU (Central Processing Unit), a non-volatile memory such as a ROM (Read Only Memory) or storage, a volatile memory such as a RAM (Random Access Memory), a transistor, a capacitor, and a resistor.

[0087] The controller 18 sets the drive conditions of the motor 6 based on the operation of the dial 16. As described above, the drive conditions of the motor 6 include a torque threshold. In the clutch mode, the controller 18 sets the torque threshold based on the operation of the dial 16.

[0088] Furthermore, in the clutch mode, the controller 18 stops the motor 6 when the torque acting on the motor 6 during driving of the motor 6 exceeds a set torque threshold value.

[0089] Furthermore, the controller 18 causes the display device 25B to display the set drive conditions of the motor 6. The controller 18 causes the display device 25B to display the set torque threshold value.

[0090] [Motor and power transmission mechanism] Fig. 4 is a cross-sectional view showing an upper portion of the driver drill 1 according to the embodiment. As shown in Fig. 4, the motor 6 has a cylindrical stator 61 and a rotor 62 disposed inside the stator 61. The rotor 62 includes a rotor shaft 63 extending in the axial direction.

[0091] The stator 61 includes a stator core 61A including a plurality of laminated steel plates, a front insulator 61B disposed in front of the stator core 61A, a rear insulator 61C disposed in the rear of the stator core 61A, a plurality of coils 61D wound around the stator core 61A via the front insulator 61B and the rear insulator 61C, a sensor circuit board 61E attached to the front insulator 61B, a fusing terminal 61F connected to the coils 61D, and a short-circuit member 61G supported by the front insulator 61B. The sensor circuit board 61E includes a plurality of rotation detection elements for detecting the rotation of the rotor 62. The short-circuit member 61G connects the plurality of coils 61D via the fusing terminal 61F. The short-circuit member 61G is connected to the controller 18 via a lead wire.

[0092] The rotor 62 rotates about a rotation axis AX. The rotor 62 has a rotor shaft 63, a rotor core 62A arranged around the rotor shaft 63, and a plurality of permanent magnets 62B held by the rotor core 62A. The rotor core 62A is cylindrical. The rotor core 62A includes a plurality of laminated steel plates. The rotor core 62A has a through hole extending in the axial direction. A plurality of through holes are formed in the circumferential direction. The permanent magnets 62B are arranged in each of the plurality of through holes of the rotor core 62A.

[0093] The rotation detection element of the sensor circuit board 61E detects the magnetic field of the permanent magnet 62B, thereby detecting the rotation of the rotor 62. The controller 18 supplies a drive current to the coil 61D based on the detection data of the rotation detection element.

[0094] The rotor shaft 63 rotates about a rotation axis AX. The rotation axis AX of the rotor shaft 63 coincides with the rotation axis of the output section 8. A front portion of the rotor shaft 63 is rotatably supported by a bearing 64. A rear portion of the rotor shaft 63 is rotatably supported by a bearing 65. The bearing 64 is held by a bracket plate 4C disposed in front of the stator 61. The bearing 65 is held by the rear cover 3. A front end portion of the rotor shaft 63 is disposed forward of the bearing 64. A front end portion of the rotor shaft 63 is disposed in the internal space of the casing 4.

[0095] A pinion gear 31S is provided at the front end of the rotor shaft 63. The rotor shaft 63 is connected to the first planetary gear mechanism 31 of the reduction mechanism 30 via the pinion gear 31S.

[0096] The first planetary gear mechanism 31 has a plurality of planetary gears 31P arranged around the pinion gear 31S, a first carrier 31C supporting the plurality of planetary gears 31P, and an internal gear 31R arranged around the plurality of planetary gears 31P. Gears are provided on the outer periphery of the first carrier 31C.

[0097] The second planetary gear mechanism 32 has a sun gear 32S, a plurality of planetary gears 32P arranged around the sun gear 32S, a second carrier 32C supporting the plurality of planetary gears 32P, and an internal gear 32R arranged around the plurality of planetary gears 32P. The sun gear 32S is arranged in front of the first carrier 31C. The diameter of the sun gear 32S is smaller than the diameter of the first carrier 31C. The first carrier 31C and the sun gear 32S are integral. The first carrier 31C and the sun gear 32S rotate together. The central axis of the internal gear 32R extends in the front-rear direction. The axial direction of the central axis of the internal gear 32R coincides with the front-rear direction.

[0098] The third planetary gear mechanism 33 has a sun gear 33S, a plurality of planetary gears 33P arranged around the sun gear 33S, a third carrier 33C supporting the plurality of planetary gears 33P, and an internal gear 33R arranged around the plurality of planetary gears 33P. The sun gear 33S is arranged in front of the second carrier 32C.

[0099] The speed reduction mechanism 30 also has a link 34 connected to the speed change lever 12, and a connecting ring 35 arranged in front of the link 34. The connecting ring 35 is fixed to the inner surface of the first casing 4A. A gear is provided on the inner periphery of the connecting ring 35. The link 34 is a wire made of, for example, a metal. The link 34 is arranged on the outside of the first casing 4A. The link 34 is movable in the front-rear direction outside the first casing 4A.

[0100] Fig. 5 is a perspective view showing the casing 4 and the link 34 according to the embodiment. Fig. 6 is an exploded perspective view showing the casing 4 and the link 34 according to the embodiment. In Figs. 5 and 6, a part of the internal configuration of the casing 4 is omitted. As shown in Figs. 5 and 6, the link 34 has a base 34a connected to the speed change lever 12, and an arm 34b extending from the base 34a to both sides in the left-right direction along the outer periphery of the first casing 4A. A tip 34c of the arm 34b is inserted into a through hole 4H provided in the first casing 4A.

[0101] The through holes 4H are provided on one side (e.g., the right side) and the other side (e.g., the left side) of the first casing 4A in the axial direction of the rotation shaft AX. The through holes 4H each extend in the front-rear direction. The tip portion 34c of the arm portion 34b is disposed inside the first casing 4A through the through hole 4H.

[0102] FIG. 7 is a side view showing the casing 4 and the link 34 according to the embodiment. FIG. 8 is a cross-sectional view showing the casing 4 and the link 34 according to the embodiment. FIG. 9 is a perspective view showing the first casing 4A and the link 34 according to the embodiment. FIG. 10 is a cross-sectional view showing the first casing 4A and the link 34 according to the embodiment. FIG. 8 shows a configuration along the AA section in FIG. 7. FIG. 9 shows a configuration along the BB section in FIG. 7. FIG. 9 omits a part of the internal configuration of the casing 4. FIG. 10 omits a part of the internal configuration of the internal gear 32R. As shown in FIG. 7 to FIG. 10, the link 34 can move between a forward position P1 where the tip 34c of the arm portion 34b is disposed at the front end of the through hole 4H and a rear position P2 where the tip 34c of the arm portion 34b is disposed at the rear end of the through hole 4H. A tip end 34c of the arm portion 34b is connected to the internal gear 32R of the second planetary gear mechanism 32 inside the first casing 4A (see FIGS. 8 and 10).

[0103] The reduction gear mechanism 30 also has a cover member 37. The cover member 37 is disposed so as to cover the gap between the through hole 4H and the link 34. The cover member 37 covers the gap between the through hole 4H of the first casing 4A and the link 34, thereby preventing the grease in the casing 4 from leaking to the outside. The cover member 37 can be formed using various materials such as a resin material, a metal material, etc. The cover member 37 may also be formed using an elastic body such as a sponge or rubber.

[0104] The cover member 37 is disposed inside the first casing 4A. The cover member 37 has a shape extending in one direction. The cover member 37 is disposed so that the longitudinal direction coincides with the front-rear direction. The cover member 37 has a tapered shape, such as a rounded shape at both ends in the longitudinal direction. This shape reduces the resistance to push aside the grease when moving in the front-rear direction, making it easier to move by pushing aside the grease. The cover member 37 may have a configuration in which at least one end in the longitudinal direction has a tapered shape. The tapered shape is not limited to the above-mentioned rounded shape, and may be another shape, such as a triangular shape, as long as it reduces the resistance to push aside the grease. The cover member 37 has a cover-side through-hole 37a in the center in the longitudinal direction. The tip portion 34c of the arm portion 34b is inserted into the cover-side through-hole 37a. The link 34 is fitted into the cover-side through-hole 37a. A tip end 34c of the arm portion 34b passes through the through hole 4H and the cover side through hole 37a to be connected to the internal gear 32R.

[0105] The cover member 37 is provided so as to be movable in conjunction with the movement of the link 34. In the embodiment, the cover member 37 is movable in the axial direction of the rotation axis AX. Guide portions 71 that guide the movement of the cover member 37 are provided on the inner circumferential surface of the first casing 4A. The guide portions 71 are disposed above and below the movement range of the cover member 37 and extend in the front-rear direction. The guide portions 71 are disposed so as to sandwich the cover member 37 in the up-down direction.

[0106] The first casing 4A is provided with a falling-off prevention portion 72. The falling-off prevention portion 72 prevents the cover member 37 from falling off from the guide portion 71. The falling-off prevention portion 72 is, for example, a portion bent downward from the inner end portion of the upper guide portion 71. The falling-off prevention portion 72 is, for example, a portion bent upward from the inner end portion of the lower guide portion 71. The falling-off prevention portion 72 can support the inner surface of the cover member 37. The falling-off prevention portion 72 is provided so as to surround the cover member 37 between the falling-off prevention portion 72 and the guide portion 71. Therefore, it is possible to prevent the cover member 37 from falling off inward from the guide portion 71.

[0107] The first casing 4A has a configuration in which the front end of the portion where the guide portion 71 and the fall-off prevention portion 72 are provided protrudes forward relative to other portions. The guide portion 71 and the fall-off prevention portion 72 are formed up to the tip of this forward-protruding protrusion 4I. With this configuration, it is possible to ensure the front-rear stroke of the guide portion 71 and the fall-off prevention portion 72 on the first casing 4A side. The second casing 4B is provided with a recess 4J corresponding to the protrusion 4I. The guide portion 71 and the fall-off prevention portion 72 may be arranged straddling from the first casing 4A side to the second casing 4B side.

[0108] The cover member 37 is movable between a forward position P3 when the tip 34c of the arm portion 34b is disposed at a forward position P1, and a rearward position P4 when the tip 34c of the arm portion 34b is disposed at a rearward position P2. The cover member 37 is formed so as to maintain a state in which the gap is covered over the entire movement range in the front-rear direction from the forward position P3 to the rearward position P4. For example, the longitudinal dimensions and the like of the cover member 37 are set so that the through hole 4H can be covered from the cover-side through hole 37a to the rear end when the cover member 37 is disposed at the forward position P3. Similarly, the longitudinal dimensions and the like of the cover member 37 are set so that the through hole 4H can be covered from the cover-side through hole 37a to the front end when the cover member 37 is disposed at the rearward position P4.

[0109] The link 34 can move in the front-rear direction together with the speed change lever 12. The speed change lever 12 is connected to the internal gear 32R via the link 34. The speed change lever 12, the link 34, and the internal gear 32R can move together. When the speed change lever 12 is operated by an operator, the link 34 moves in the front-rear direction outside the first casing 4A. The link 34 can move in the front-rear direction between the front position P1 and the rear position P2 while the internal gear 32R and the planetary gear 32P are engaged with each other, so that the internal gear 32R can be moved between the low-speed mode position PL and the high-speed mode position PH rearward of the low-speed mode position PL, as shown in FIG. 8. When the internal gear 32R moves in the front-rear direction between the low-speed mode position PL and the high-speed mode position PH, the low-speed mode and the high-speed mode are switched. When the speed change lever 12 is operated, the low-speed mode and the high-speed mode are switched.

[0110] When the internal gear 32R is disposed at the low speed mode position PL, it comes into contact with the coupling ring 35. The internal gear 32R comes into contact with the coupling ring 35, thereby restricting the rotation of the internal gear 32R. When the internal gear 32R is disposed at the high speed mode position PH, it moves away from the coupling ring 35. The internal gear 32R moves away from the coupling ring 35, thereby allowing the internal gear 32R to rotate.

[0111] Furthermore, when the internal gear 32R is disposed at the low speed mode position PL, it meshes with the planetary gear 32P. When the internal gear 32R is disposed at the high speed mode position PH, it meshes with both the planetary gear 32P and the first carrier 31C.

[0112] When the internal gear 32R is disposed at the low speed mode position PL, the rotor shaft 63 rotates by being driven by the motor 6, so that the pinion gear 31S rotates and the planetary gear 31P revolves around the pinion gear 31S. The revolution of the planetary gear 31P causes the first carrier 31C and the sun gear 32S to rotate at a rotational speed lower than the rotational speed of the rotor shaft 63. When the sun gear 32S rotates, the planetary gear 32P revolves around the sun gear 32S. The revolution of the planetary gear 32P causes the second carrier 32C and the sun gear 33S to rotate at a rotational speed lower than the rotational speed of the first carrier 31C. In this manner, when the motor 6 is driven with the internal gear 32R disposed at the low-speed mode position PL, both the speed reduction function of the first planetary gear mechanism 31 and the speed reduction function of the second planetary gear mechanism 32 are exerted, and the second carrier 32C and the sun gear 33S rotate in the low-speed mode. In this state, the cover member 37 is disposed at the front position P3. The cover member 37 covers the through-hole 4H with the portion from the cover-side through-hole 37a to the rear end.

[0113] When the rotor shaft 63 rotates by the drive of the motor 6 while the internal gear 32R is disposed at the high speed mode position PH, the pinion gear 31S rotates and the planetary gear 31P revolves around the pinion gear 31S. Due to the revolution of the planetary gear 31P, the first carrier 31C and the sun gear 32S rotate at a rotation speed lower than the rotation speed of the rotor shaft 63. Since the internal gear 32R meshes with both the planetary gear 32P and the first carrier 31C while the internal gear 32R is disposed at the high speed mode position PH, the internal gear 32R and the first carrier 31C rotate together. Due to the rotation of the internal gear 32R, the planetary gear 32P revolves at the same revolution speed as the rotation speed of the internal gear 32R. Due to the revolution of the planetary gear 32P, the second carrier 32C and the sun gear 33S rotate at the same rotation speed as the first carrier 31C. In this manner, when the motor 6 is driven in a state in which the internal gear 32R is disposed at the high speed mode position PH, the speed reduction function of the first planetary gear mechanism 31 is exerted but the speed reduction function of the second planetary gear mechanism 32 is not exerted, and the second carrier 32C and the sun gear 33S rotate in the high speed mode. In this state, the cover member 37 is disposed at the rear position P4. The cover member 37 is in a state in which the through hole 4H is covered by the portion from the cover side through hole 37a to the front end portion.

[0114] When second carrier 32C and sun gear 33S rotate, planetary gear 33P revolves around sun gear 33S. The revolution of planetary gear 33P rotates third carrier 33C.

[0115] The spindle 81 is connected to the third carrier 33C via a lock cam 85 (see FIG. 4). The spindle 81 is splined to the lock cam 85. The lock cam 85 is rotatably supported by a lock ring 86. The lock ring 86 is disposed inside the second casing 4B. The lock ring 86 is fixed to the second casing 4B. The spindle 81 rotates due to the rotation of the third carrier 33C.

[0116] The spindle 81 is rotatably supported by a bearing 83 and a bearing 84. While being supported by the bearings 83 and 84, the spindle 81 is movable in the front-rear direction.

[0117] The spindle 81 has a flange portion 81F. A coil spring 87 is disposed between the flange portion 81F and the bearing 83. The coil spring 87 generates an elastic force that moves the spindle 81 forward.

[0118] The chuck 82 is capable of holding a tool bit. The chuck 82 is connected to the front part of the spindle 81. The chuck 82 rotates as the spindle 81 rotates. The chuck 82 rotates while holding the tool bit.

[0119] The first cam 41 and the second cam 42 of the vibration mechanism 40 are disposed inside the second casing 4B. The first cam 41 and the second cam 42 are disposed between the bearing 83 and the bearing 84 in the front-rear direction.

[0120] The first cam 41 is ring-shaped. The first cam 41 is disposed around the spindle 81. The first cam 41 is fixed to the spindle 81. The first cam 41 rotates together with the spindle 81. Cam teeth are provided on the rear surface of the first cam 41. The first cam 41 is supported by a stop ring 44. The stop ring 44 is disposed around the spindle 81. In the front-rear direction, the stop ring 44 is disposed between the first cam 41 and the bearing 83. The elastic force of the coil spring 87 causes the stop ring 44 to contact the rear surface of the bearing 83.

[0121] The second cam 42 is ring-shaped. The second cam 42 is disposed behind the first cam 41. The second cam 42 is disposed around the spindle 81. The second cam 42 is rotatable relative to the spindle 81. Cam teeth are provided on a front surface of the second cam 42. The cam teeth on the front surface of the second cam 42 mesh with the cam teeth on the rear surface of the first cam 41. A pawl is provided on the rear surface of the second cam 42.

[0122] A support ring 45 is disposed between the second cam 42 and the bearing 84 in the front-rear direction. The support ring 45 is disposed inside the second casing 4B. The support ring 45 is fixed to the second casing 4B. A plurality of steel balls 46 are disposed on the front side of the support ring 45. A washer 47 is disposed between the steel balls 46 and the second cam 42. The second cam 42 is rotatable in a space defined by the small diameter portion 402 and the washer 47 with its front-rear movement restricted.

[0123] The vibration switching ring 43 switches between a vibration mode and a non-vibration mode. The mode switching ring 13 is connected to the vibration switching ring 43 via a cam ring 48. The mode switching ring 13 and the cam ring 48 can rotate together. The vibration switching ring 43 can move in the front-rear direction. The vibration switching ring 43 has a protrusion 43T. The protrusion 43T is inserted into a guide hole provided in the second casing 4B. The vibration switching ring 43 can move in the front-rear direction while being guided by the guide hole provided in the second casing 4B. The rotation of the vibration switching ring 43 is restricted by the protrusion 43T. When the mode switching ring 13 is operated by an operator, the vibration switching ring 43 moves in the front-rear direction. The vibration switching ring 43 switches between the vibration mode and the non-vibration mode by moving in the front-rear direction between a forward position and a backward position that is further rearward than the forward position. By operating the mode switching ring 13, the vibration mode and the non-vibration mode can be switched.

[0124] The vibration mode includes a state in which the rotation of the second cam 42 is restricted. The non-vibration mode includes a state in which the rotation of the second cam 42 is permitted. When the vibration switching ring 43 moves to the forward position, the rotation of the second cam 42 is restricted. When the vibration switching ring 43 moves to the backward position, the rotation of the second cam 42 is permitted.

[0125] In the vibration mode, at least a part of the vibration switching ring 43 that has moved to the forward position comes into contact with the second cam 42. The contact between the vibration switching ring 43 and the second cam 42 restricts the rotation of the second cam 42. When the motor 6 is driven in a state in which the rotation of the second cam 42 is restricted, the first cam 41 fixed to the spindle 81 rotates while contacting the cam teeth of the second cam 42. As a result, the spindle 81 rotates while vibrating in the front-rear direction.

[0126] In the non-vibration mode, the vibration switching ring 43, which has moved to the retracted position, moves away from the second cam 42. The movement of the vibration switching ring 43 and the second cam 42 away from each other allows the second cam 42 to rotate. When the motor 6 is driven in a state in which the rotation of the second cam 42 is allowed, the second cam 42 rotates together with the first cam 41 and the spindle 81. As a result, the spindle 81 rotates without vibrating in the front-rear direction.

[0127] The vibration switching ring 43 is disposed around the first cam 41 and the second cam 42. The vibration switching ring 43 also has a facing portion 43S that faces the rear surface of the second cam 42. The facing portion 43S protrudes from the rear of the vibration switching ring 43 radially inward.

[0128] When the mode switching ring 13 is operated and the vibration switching ring 43 moves to the forward position, the claw on the rear surface of the second cam 42 comes into contact with the opposing portion 43S of the vibration switching ring 43. This restricts the rotation of the second cam 42. In this manner, when the mode switching ring 13 is operated and the vibration switching ring 43 moves to the forward position, the vibration mechanism 40 is switched to the vibration mode.

[0129] When the mode switching ring 13 is operated and the vibration switching ring 43 moves to the retracted position, the opposing portion 43S of the vibration switching ring 43 moves away from the second cam 42. This allows the second cam 42 to rotate. In this manner, when the mode switching ring 13 is operated and the vibration switching ring 43 moves to the retracted position, the vibration mechanism 40 is switched to the non-vibration mode.

[0130] Fig. 11 is a perspective view showing another casing 104 and a link 134 according to the embodiment. Fig. 12 is an exploded perspective view showing the casing 104 and the link 134 according to the embodiment. In Figs. 11 and 12, a part of the internal configuration of the casing 104 is omitted. As shown in Figs. 11 and 12, the arm portion 134b of the link 134 extends from the base portion 134a to both sides in the left-right direction along the outer periphery of the first casing 104A. The tip portion 134c of the arm portion 134b is inserted into a through hole 104H provided in the first casing 104A.

[0131] Fig. 13 is a side view showing the casing 104 and the link 134 according to the embodiment. Fig. 14 is a cross-sectional view showing the casing 104 and the link 134 according to the embodiment. Fig. 15 is a cross-sectional view showing the first casing 104A and the link 134 according to the embodiment. Fig. 14 shows the configuration along the CC cross section in Fig. 13. Fig. 15 shows the configuration along the DD cross section in Fig. 13. In Fig. 15, the inner configuration of the internal gear 32R is partially omitted.

[0132] 12 to 15, the link 134 of the reduction gear mechanism 130 is movable between a forward position P11 where the tip 134c of the arm portion 134b is disposed at the front end of the through hole 104H and a rearward position P12 where the tip 134c of the arm portion 134b is disposed at the rear end of the through hole 104H. The tip 134c of the arm portion 134b is connected to the internal gear 32R of the second planetary gear mechanism 32 inside the first casing 104A (see FIGS. 14 and 15).

[0133] The reduction gear mechanism 130 also has a cover member 137. The cover member 137 is disposed so as to cover the gap between the through hole 104H and the link 134. The cover member 137 covers the gap between the through hole 104H of the first casing 104A and the link 134, thereby preventing the grease in the casing 104 from leaking to the outside. The cover member 137 can be formed using various materials such as a resin material, a metal material, etc. The cover member 137 may be formed using an elastic body such as a sponge or rubber.

[0134] The cover member 137 is disposed outside the first casing 104A. The cover member 137 is formed, for example, in a plate shape, and has a base portion 137a and a covering portion 137b. The base portion 137a is provided in a band shape along the axial direction. The covering portion 137b extends from the base portion 137a in a direction perpendicular to the axial direction. The covering portion 137b is provided with a cover-side through-hole 137c into which the link 134 is inserted. The tip portion 134c of the arm portion 134b is inserted into the cover-side through-hole 137c. The tip portion 134c of the arm portion 134b passes through the through-hole 104H from the cover-side through-hole 137c and is connected to the internal gear 32R. The cover-side through-hole 137c extends in a direction inclined with respect to the axial direction. The cover member 137 is shaped such that the base portion 137a protrudes on both sides in the front-rear direction relative to the covering portion 137b.

[0135] The cover member 137 is provided so as to be movable in conjunction with the movement of the link 134. In this configuration, the cover member 137 is movable along the surface 104F of the first casing 104A in a direction intersecting the axial direction. Guide portions 171 that guide the movement of the cover member 137 are provided on the outer peripheral surfaces of the first casing 104A and the second casing 104B. The guide portions 171 are disposed in front of and behind the movement range of the cover member 137 and extend in the front-rear direction. The guide portions 171 are disposed so as to sandwich the cover member 137 in the front-rear direction.

[0136] The first casing 104A and the second casing 104B are provided with a falling-off prevention portion 172. The falling-off prevention portion 172 prevents the cover member 137 from falling off the guide portion 171. The falling-off prevention portion 172a is, for example, a portion bent forward from the outer end of the guide portion 171a on the rear side (first casing 104A side). The falling-off prevention portion 172b is, for example, a portion protruding backward from the guide portion 171b on the front side (second casing 104B side). The falling-off prevention portion 172 can support the outer surface of the cover member 137. The falling-off prevention portion 172 is provided so as to surround the cover member 137 between the falling-off prevention portion 172 and the guide portion 171. Therefore, it is possible to prevent the cover member 137 from falling outward from the guide portion 171. The falling-off prevention portion 172 is not limited to being provided on the casing 104 (the first casing 104A and the second casing 104B). The falling-off prevention portion 172 may be provided on, for example, the housing 2 (the left housing 2L and the right housing 2R).

[0137] The first casing 104A and the second casing 104B are provided with stoppers 173 (see FIG. 13). The stoppers 173 are disposed inside the fall-off prevention portion 172. The stoppers 173 are disposed at the ends of the cover member 137 in the movement direction. The stoppers 173 regulate the movement of the cover member 137. The stoppers 173 can position the cover member 137. The stoppers 173 are disposed so as to abut against the protruding portion of the base 137a of the cover member 137. In this configuration, the cover member 137 can be appropriately positioned at the lower position P13 by abutting the protruding portion of the base 137a of the cover member 137 against the stoppers.

[0138] The cover member 137 can move between a lower position P13 and an upper position P14. The lower position P13 is a position when the tip 134c of the arm portion 134b is disposed at a forward position P11. The upper position P14 is a position when the tip 134c of the arm portion 134b is disposed at a rearward position P12. The cover member 137 has a cover-side through hole 137c extending in a direction inclined with respect to the axial direction, so that the cover member 137 moves up and down according to the inclination as the arm portion 134b moves forward and backward. Specifically, the cover-side through hole 137c is formed so as to extend upward toward the front. Therefore, when the arm portion 134b moves forward, the cover member 137 is pushed down by the arm portion 134b and moves downward. Also, when the arm portion 134b moves backward, the cover member 137 is pushed up by the arm portion 134b and moves upward.

[0139] The cover member 137 is formed to maintain the gap covered throughout the entire range of movement in the front-rear direction from the lower position P13 to the upper position P14. For example, when the cover member 137 is disposed at the lower position P13, the cover member 137 can cover the through-hole 104H at the rear of the cover-side through-hole 137c. Similarly, when the cover member 137 is disposed at the upper position P14, the cover member 137 can cover the through-hole 104H at the front of the cover-side through-hole 137c.

[0140] Fig. 16 is a perspective view showing another casing 204 and a link 234 according to the embodiment. Fig. 17 is an exploded perspective view showing a casing 204 and a link 234 according to the embodiment. In Figs. 16 and 17, a part of the internal configuration of the casing 204 is omitted. As shown in Figs. 16 and 17, an arm portion 234b of the link 234 extends from a base portion 234a to both sides in the left-right direction along the outer periphery of the first casing 204A. A tip portion 234c of the arm portion 234b is inserted into a through hole 204H provided in the first casing 204A.

[0141] The link 234 of the reduction gear mechanism 130 is movable between a forward position P21 where the tip 234c of the arm portion 234b is disposed at the front end of the through hole 204H and a rearward position P22 where the tip 234c of the arm portion 234b is disposed at the rear end of the through hole 204H. The tip 234c of the arm portion 234b is connected to the internal gear 32R of the second planetary gear mechanism 32 inside the first casing 204A.

[0142] Moreover, the speed reduction mechanism 230 has a cover member 237. The cover member 237 is disposed so as to cover the gap between the through hole 204H and the link 234. The cover member 237 covers the gap between the through hole 204H of the first casing 204A and the link 234, thereby preventing the grease in the casing 204 from leaking to the outside.

[0143] The cover member 237 is disposed outside the first casing 204A. For example, the cover member 237 is provided in the recess 204G of the first casing 204A. The cover member 237 is formed in a plate shape from an elastic body that can be elastically deformed, such as sponge or rubber. The cover member 237 may be formed using a porous material. When the cover member 237 is formed using a porous material, it can absorb grease. The cover member 237 has a cover-side through hole 237a. The cover-side through hole 237a is formed in the front-rear direction along the through hole 204H of the casing 204. The cover-side through hole 237a is formed so that the width in the up-down direction is smaller than the diameter of the arm portion 234b. In the embodiment, the cover-side through hole 237a is a linear cut portion along the front-rear direction. When the tip 234c of the arm portion 234b is inserted into the cover-side through-hole 237a, the cover member 237 is elastically deformed so that the cover-side through-hole 237a widens at the inserted portion. Also, the portion of the cover-side through-hole 237a other than the inserted portion remains in a state where it does not widen in the vertical direction. When the arm portion 234b moves in the front-rear direction, the arm portion 234b is elastically deformed with the movement of the arm portion 234b, and the position where it widens in the vertical direction changes. Therefore, when the arm portion 234b is inserted, it is possible to appropriately cover the space between the through-hole 204H and the link 234 (arm portion 234b).

[0144] In this embodiment, the driver drill (power tool) 1 may have a motor 6, a planetary gear 32P driven by the motor 6, an internal gear 32R meshing with the planetary gear 32P, a casing 4 accommodating the planetary gear 32P and the internal gear 32R, through holes 4H provided on one and the other lateral sides of the casing 4 relative to the axial direction of the rotation axis AX, links 34 inserted into each of the through holes 4H and capable of moving the internal gear 32R in the axial direction, and a cover member 37 covering the gap between the through holes 4H and the links 34.

[0145] In the above configuration, the gap between the through hole 4H of the casing 4 and the link 34 is covered with the cover member 37. This makes it possible to prevent the grease in the casing 4 from leaking to the outside.

[0146] In the present embodiment, the cover member 37 may be provided so as to be movable in conjunction with the movement of the link 34 .

[0147] In the above configuration, since the cover member 37 is movable in conjunction with the movement of the link 34, it is possible to cover the gap without interfering with the movement of the link 34.

[0148] In this embodiment, the cover member 37 is formed so as to maintain the gap covered throughout the entire range of movement in conjunction with the link 34 .

[0149] In the above configuration, the cover member 37 maintains a state in which the gap is covered over the entire range of movement, so that the grease inside the casing 4 can be more appropriately prevented from leaking to the outside.

[0150] In this embodiment, the cover member 37 has a rounded shape at least on one end in the movement direction.

[0151] In the above configuration, at least one end of the cover member 37 in the movement direction has a rounded shape, so that the cover member 37 can easily move by pushing aside the grease when it moves.

[0152] In this embodiment, the cover member 37 is axially movable.

[0153] In the above-described configuration, in a configuration in which the cover member 37 is provided so as to be movable in the axial direction, it is possible to prevent the grease inside the casing 4 from leaking to the outside.

[0154] In this embodiment, the cover member 137 is movable along the surface 104F of the casing 104 in a direction intersecting the axial direction.

[0155] In the above configuration, in a configuration in which cover member 137 is provided movably in a direction intersecting the axial direction along surface 104F of casing 104, it is possible to prevent grease inside casing 4 from leaking to the outside.

[0156] In this embodiment, the cover member 137 has a cover-side through-hole 137c extending in a direction inclined with respect to the axial direction.

[0157] In the above configuration, the cover member 137 has a cover side through hole 137c extending in a direction inclined relative to the axial direction, so that when the link 134 moves in the axial direction, the cover member 137 can be appropriately moved in a direction intersecting the axial direction in accordance with the inclination of the cover side through hole 137c.

[0158] In this embodiment, the casing 4 has a guide portion 71 that guides the cover member 37 .

[0159] In the above configuration, since the casing 4 has the guide portion 71 that guides the cover member 37, the cover member 37 can be moved smoothly in conjunction with the movement of the link .

[0160] In this embodiment, the guide portions 71 are disposed on both sides of the cover member 37 in the moving direction.

[0161] In the above configuration, the guide portions 71 are disposed on both sides of the cover member 37 in the moving direction, so that the cover member 37 can be guided more appropriately.

[0162] In this embodiment, the casing 4 has a fall-off prevention portion 72 that prevents the cover member 37 from falling off the guide portion 71.

[0163] In the above configuration, the anti-fall-out portion 72 prevents the cover member 37 from falling off from the guide portion 71, thereby allowing the cover member 37 to move smoothly while appropriately preventing the grease inside the casing 4 from leaking to the outside.

[0164] In this embodiment, the fall-off prevention portion 72 is provided so as to surround the cover member 37 between itself and the guide portion 71 .

[0165] In the above configuration, the fall-off prevention portion 72 is provided so as to surround the cover member 37 between itself and the guide portion 71, so that the cover member 37 can be appropriately prevented from falling off.

[0166] In this embodiment, the casing 104 has a stopper 173 disposed at an end of the cover member 137 in the moving direction.

[0167] In the above configuration, since the stopper 173 is provided at the end of the casing 104 in the moving direction of the cover member 137, the cover member 137 can be appropriately positioned.

[0168] In this embodiment, the cover member 137 has a shape that protrudes laterally in the direction of movement, and the stopper 173 is disposed at a position where it comes into contact with the protruding portion of the cover member 137 .

[0169] In the above configuration, cover member 137 has a shape that protrudes laterally in the direction of movement, and stopper 173 is positioned at a position where it abuts the protruding portion of cover member 137, so that cover member 137 can be appropriately positioned by abutting the protruding portion of cover member 137 against stopper 173.

[0170] In this embodiment, the cover member 37 is disposed inside the casing 4 .

[0171] In the above configuration, since the cover member 37 is disposed inside the casing 4, it is possible to cover the gap from the inside of the through hole 4H. This makes it possible to appropriately prevent the grease inside the casing 4 from leaking to the outside.

[0172] In this embodiment, the cover member 37 is disposed outside the casing 4 .

[0173] In the above configuration, since the cover member 37 is disposed outside the casing 4, it is possible to cover the gap from the outside of the through-hole 4H. This makes it possible to appropriately prevent the grease inside the casing 4 from leaking to the outside.

[0174] In this embodiment, the cover member 237 is formed using an elastic body that deforms in response to the movement of the link 234 .

[0175] In the above configuration, since the cover member 237 is formed using an elastic body that deforms in response to the movement of the link 234, it is possible to cover the gap without impeding the movement of the link 234.

[0176] In this embodiment, the cover member 237 has a cover-side through-hole 237a extending in the axial direction, and the cover-side through-hole 237a has a width smaller than the diameter of the link 234.

[0177] In the above configuration, the cover member 237 has a cover-side through hole 237a extending in the axial direction, and the width of the cover-side through hole 237a is smaller than the diameter of the link 234. Therefore, by inserting the link 234 into the cover-side through hole 237a, the cover-side through hole 237a elastically deforms so as to expand at the portion where the link 234 is inserted. The portion of the cover-side through hole 237a other than the inserted portion maintains a state in which it does not expand in the vertical direction. When the link 234 moves, the cover member 237 elastically deforms with the movement of the link 234, and the position where it expands in the vertical direction changes. Therefore, the cover member 237 can appropriately cover the area between the through hole 204H and the link 234 when the link 234 is inserted.

[0178] In this embodiment, the cover side through-hole 237a includes a linear cut portion.

[0179] In the above configuration, since the cover-side through-hole 237a includes a linear cut portion, the area between the through-hole 204H and the link 234 can be appropriately covered in a portion other than the portion where the link 234 is inserted.

[0180] In this embodiment, the cover member 237 is formed using a porous material.

[0181] In the above configuration, the cover member 237 is made of a porous material and is therefore capable of absorbing grease.

[0182] In this embodiment, the driver drill (electric power tool) 1 includes a motor 6, a planetary gear 32P arranged in front of the motor 6 and driven by the motor 6, an internal gear 32R meshing with the planetary gear 32P, a casing 4 accommodating the planetary gear 32P and the internal gear 32R, an output section 8 arranged in front of the planetary gear 32P and driven by the planetary gear 32P, a through hole (right through groove) 4H provided in the right part of the casing 4 and extending in the front-rear direction, and a through hole (right through groove) 4H provided in the left part of the casing 4. The casing 4 has a through hole (left through groove) 4H extending in the front-to-rear direction, a link (right link) 34 inserted into the through hole 4H in the right part of the casing 4 and capable of moving the internal gear 32R in the front-to-rear direction, a link (left link) 34 inserted into the through hole 4H in the left part of the casing 4 and capable of moving the internal gear 32R in the front-to-rear direction, a cover member (right cover member) 39 covering the gap between the right through hole 4H and the link 34, and a cover member (left cover member) 39 covering the gap between the left through hole 4H and the link 34.

[0183] With the above-described configuration, in the driver drill 1 having the output portion 8 driven by the planetary gear 32P, it is possible to appropriately prevent the grease in the casing 4 from leaking to the outside.

[0184] In the above-described embodiment, the power tool is the driver drill 1. The power tool may be a polisher, a pin cutter, a hammer drill, an impact driver, or an impact wrench. [Explanation of symbols]

[0185] 1...driver drill, 2...housing, 2L...left housing, 2R...right housing, 2S, 3S, 4E, 4S, 5S...screws, 3...rear cover, 4,104, 204...casing, 4A, 104A, 204A...first casing, 4B, 104B...second casing, 4C...bracket plate, 4D...stop plate, 4F...surface, 4H, 104H, 204H...through hole, 4I, 43T...projection, 4J...recess, 5...battery mounting section, 6...motor, 7...power transmission mechanism, 8...output section, 9...fan, 10...trigger lever, 11...forward / reverse switching lever, 12...speed switching lever , 13...mode switching ring, 14...light unit, 15...interface panel, 16...dial, 17...trigger signal generating circuit, 18...controller, 18A...controller board, 19A...air intake, 19B...exhaust, 20...battery, 21...motor housing, 22...grip, 23...battery holder, 24...light holder, 25A...operation device, 25B...display device, 26...controller case, 27...panel opening, 28...dial opening, 29...light opening, 30, 130, 230...reduction mechanism, 31...first planetary gear mechanism, 31C...first carrier, 3 1P, 32P, 33P... planetary gears, 31R, 32R, 33R... internal gears, 31S... pinion gears, 32... second planetary gear mechanism, 32C... second carrier, 32S, 33S... sun gears, 33... third planetary gear mechanism, 33C... third carrier, 34, 134, 234... links, 34a, 134a, 137a, 234a... base, 34b, 134b, 234b... arm portion, 35... coupling ring, 37, 137, 237... cover member, 37a, 137c... cover side through hole, 40... vibration mechanism, 41... first cam, 42... second cam, 43... vibration switching ring, 43 S... opposing portion, 44... stop ring, 45... support ring, 46... steel ball, 47... washer, 48... cam ring, 49... mode detection ring, 49M, 62B... permanent magnet, 61... stator, 61A... stator core, 61B... front insulator, 61C... rear insulator, 61D... coil, 61E... sensor circuit board, 61F... fusing terminal, 61G... short circuit member, 62... rotor, 62A... rotor core, 63... rotor shaft, 64, 65, 83, 84... bearing, 71, 171, 171a, 171b... guide portion, 72, 172, 172a,172b... Falling prevention portion, 81... Spindle, 81F... Flange portion, 82... Chuck, 85... Lock cam, 86... Lock ring, 87... Coil spring, 137b... Covering portion, 173... Stopper, 237a... Cover side through hole, 402... Small diameter portion, P1, P11, P3, P21... Front position, P2, P12, P4, P22... Rear position, P13... Lower position, P14... Upper position, PH... High speed mode position, AX... Rotating axis, PL... Low speed mode position,

Claims

1. Motor and, Planetary gears driven by the aforementioned motor, An internal gear that meshes with the aforementioned planetary gear, A casing that houses the planetary gear and the internal gear, The casing includes through holes provided on one and the other sides of the casing relative to the axial direction of the central axis of the internal gear, A link is inserted into each of the aforementioned through holes, and the internal gear is movable in the axial direction, A cover member that covers the gap between the through hole and the link. Power tools that possess [certain characteristics].

2. The cover member is provided so as to be movable in conjunction with the movement of the link. The power tool according to claim 1.

3. The cover member is formed to maintain a state of covering the gap over the entire range of movement that moves in conjunction with the movement of the link. The power tool according to claim 2.

4. The cover member has a tapered shape at least one end in the direction of movement. The power tool according to claim 2.

5. The cover member is movable in the axial direction. The power tool according to claim 2.

6. The cover member is movable along the surface of the casing in a direction intersecting the axial direction. The power tool according to claim 2.

7. The cover member has a cover-side through hole that extends in a direction inclined with respect to the axial direction. The power tool according to claim 6.

8. The casing has a guide portion that guides the cover member. The power tool according to claim 2.

9. The guide portion is positioned on both sides of the cover member in the direction of movement. The power tool according to claim 8.

10. The casing has a detachment prevention portion that prevents the cover member from falling off the guide portion. The power tool according to claim 8.

11. The detachment prevention portion is provided so as to surround the cover member between itself and the guide portion. The power tool according to claim 10.

12. The casing has a stopper positioned at the end of the cover member in the direction of movement. The power tool according to claim 2.

13. The cover member has a shape that protrudes laterally in the direction of movement, The stopper is positioned to strike the protruding portion of the cover member. The power tool according to claim 12.

14. The cover member is disposed inside the casing. The power tool according to claim 1.

15. The cover member is positioned outside the casing. The power tool according to claim 1.

16. The cover member is formed using an elastic body that deforms in accordance with the movement of the link. The power tool according to claim 1.

17. The cover member has a cover-side through hole extending in the axial direction, The through hole on the cover side is narrower than the diameter of the link. The power tool according to claim 16.

18. The cover-side through-hole includes a linear cut portion. The power tool according to claim 17.

19. The cover member is formed using a porous material. The power tool according to claim 16.

20. Motor and, A planetary gear positioned in front of the motor and driven by the motor, An internal gear that meshes with the aforementioned planetary gear, A casing that houses the planetary gear and the internal gear, An output unit positioned in front of the planetary gear and driven by the planetary gear, A right through groove extending in the front-rear direction is provided on the right side of the casing, A left through groove extending in the front-rear direction is provided on the left side of the casing, A right link is inserted into the right through groove and is capable of moving the internal gear in the front-rear direction, A left link is inserted into the left through groove and is capable of moving the internal gear in the front-rear direction, A right cover member that covers the gap between the right through groove and the right link, A left cover member that covers the gap between the left through groove and the left link, Power tools that possess [certain characteristics].

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