Electric work machine

Abstract

To provide an electric work machine which is suppressed from enlarging in size.SOLUTION: The electric work machine is provided with: a motor which has a stator and a rotor at least a portion of which is arranged inside the stator and which rotates with a rotation axis as a center; a spindle, arranged closer to a front side than the stator in a longitudinal direction which is parallel to the rotation axis, which is rotated by rotation force generated by the rotor; and a spindle bearing that rotatably bears a rear part of the spindle. The spindle bearing is arranged inside in a radial direction of the stator.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] 2. Description of the Related Art In the technical field related to impact tools, a power tool such as that disclosed in Patent Document 1 is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2021 / 0187707 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to improve the workability when using an electric work machine, a technique is required that prevents the electric work machine from becoming larger.

[0005] The technology disclosed in this specification aims to prevent an increase in size of an electric operating machine. [Means for solving the problem]

[0006] This specification discloses an electric working machine. The electric working machine may include a motor having a stator and a rotor at least a portion of which is disposed inside the stator and rotates about a rotation shaft, a spindle disposed forward of the stator in a front-rear direction parallel to the rotation shaft and rotated by a rotational force generated by the rotor, and a spindle bearing rotatably supporting a rear portion of the spindle. The spindle bearing may be disposed radially inside the stator. Effect of the Invention

[0007] According to the technology disclosed in this specification, an increase in size of an electric operating machine is suppressed. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing an electric operating machine according to an embodiment, as seen from the front. [Diagram 2] FIG. 2 is a perspective view showing a part of the electric operating machine according to the embodiment, seen from the rear. [Diagram 3] FIG. 3 is a side view showing a part of the electric operating machine according to the embodiment. [Figure 4] FIG. 4 is a vertical cross-sectional view showing a part of the electric operating machine according to the embodiment. [Diagram 5] FIG. 5 is a cross-sectional view showing a part of the electric operating machine according to the embodiment. [Figure 6] FIG. 6 is a perspective cross-sectional view showing a part of the electric operating machine according to the embodiment. [Figure 7] FIG. 7 is an exploded perspective view, seen from the front, showing a part of the electric operating machine according to the embodiment. [Figure 8] FIG. 8 is an exploded perspective view showing a part of the electric operating machine according to the embodiment, as seen from the rear. [Figure 9] FIG. 9 is a front perspective view showing the motor according to the embodiment. [Figure 10] FIG. 10 is an exploded perspective view showing the motor according to the embodiment, as viewed from the front. [Figure 11] FIG. 11 is an exploded perspective view showing the stator according to the embodiment, as viewed from the front. [Figure 12] FIG. 12 is an exploded perspective view, seen from the front, showing a part of the electric operating machine according to the embodiment. [Figure 13] FIG. 13 is an exploded perspective view showing a part of the electric operating machine according to the embodiment, as seen from the rear. [Figure 14] FIG. 14 is a cross-sectional view showing the operation of the electric operating machine according to the embodiment. [Figure 15] FIG. 15 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. [Figure 16] FIG. 16 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. [Figure 17]FIG. 17 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. [Figure 18] FIG. 18 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. [Figure 19] FIG. 19 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. [Figure 20] FIG. 20 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. [Figure 21] FIG. 21 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. [Figure 22] FIG. 22 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. [Figure 23] FIG. 23 is a cross-sectional view showing the operation of the electric operating machine according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In one or more embodiments, the electric operating machine may include a motor having a stator and a rotor at least partially disposed inside the stator and rotating about a rotation axis, a spindle disposed forward of the stator in a front-rear direction parallel to the rotation axis and rotated by a rotational force generated by the rotor, and a spindle bearing rotatably supporting a rear portion of the spindle. The spindle bearing may be disposed radially inside the stator.

[0010] In the above configuration, the spindle bearing is positioned radially inside the stator and overlaps at least a portion of the stator in the fore-and-aft direction, thereby preventing the electric work machine from becoming larger in the fore-and-aft direction parallel to the motor's rotating shaft.

[0011] In one or more embodiments, the stator may include a stator core and an insulator fixed at least in part to a front portion of the stator core. The spindle bearing may be disposed radially inward of the insulator.

[0012] In the above configuration, the spindle bearing is positioned radially inside the insulator and overlaps at least a portion of the insulator in the front-to-rear direction, thereby preventing the electric work machine from becoming larger in the front-to-rear direction parallel to the motor's rotating shaft.

[0013] In one or more embodiments, the electric operating machine may include a bearing box that holds the spindle bearing. The insulator may be connected to the bearing box.

[0014] In the above configuration, the relative movement between the stator and the bearing box is suppressed.

[0015] In one or more embodiments, the bearing box may have an insertion hole into which a pin portion provided in the insulator is inserted.

[0016] In the above configuration, the insulator and the bearing box are connected together by inserting the pin portion into the insertion hole.

[0017] In one or more embodiments, the bearing box may have a first protrusion that contacts the front end surface of the stator core.

[0018] In the above configuration, the stator is supported by the first protrusion of the bearing box.

[0019] In one or more embodiments, the electric work machine may include a hammer case that houses the spindle. The bearing box may be disposed to cover an opening at a rear end of the hammer case.

[0020] In the above configuration, the bearing box and the hammer case are connected.

[0021] In one or more embodiments, the electric operating machine may include a rear case that houses at least a portion of the motor. The rear case and the hammer case may be fixed to each other by a screw.

[0022] In the above configuration, the relative movement between the rear case and the hammer case is suppressed.

[0023] In one or more embodiments, the hammer case may have a second protrusion that contacts the front end surface of the rear case.

[0024] In the above configuration, the rear case is supported by the first protrusion of the hammer case.

[0025] Hereinafter, an embodiment will be described with reference to the drawings. The components of the embodiment described below can be appropriately combined. In addition, there are cases where some components are not used.

[0026] 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 operating machine. The electric operating machine has a motor 6 as a power source.

[0027] In the embodiment, the direction parallel to the rotation axis AX of the motor 6 is referred to as the axial direction, the direction circumferential around the rotation axis AX is referred to as the circumferential direction or rotation direction, and the radial direction of the rotation axis AX is referred to as the radial direction.

[0028] A direction or position away from the center of the electric operating machine in a specified direction in the axial direction is appropriately referred to as one axial side, and the opposite side of the one axial side is appropriately referred to as the other axial side. A specified direction in the circumferential direction is appropriately referred to as one circumferential side, and the opposite side of the one circumferential side is appropriately referred to as the other circumferential side. A direction or position away from the rotation axis AX in the radial direction is appropriately referred to as the radial outer side, and the opposite side of the radial outer side is appropriately referred to as the radial inner side.

[0029] In the embodiment, the axial direction and the front-rear direction coincide with each other. One side in the axial direction may be regarded as the front. The other side in the axial direction may be regarded as the rear.

[0030] [Electric work equipment] FIG. 1 is a front perspective view of an electric working machine 1 according to an embodiment. FIG. 2 is a rear perspective view of a part of the electric working machine 1 according to an embodiment. FIG. 3 is a side view of a part of the electric working machine 1 according to an embodiment. FIG. 4 is a vertical cross-sectional view of a part of the electric working machine 1 according to an embodiment. FIG. 5 is a horizontal cross-sectional view of a part of the electric working machine 1 according to an embodiment. FIG. 6 is a perspective cross-sectional view of a part of the electric working machine 1 according to an embodiment. FIG. 7 is an exploded front perspective view of a part of the electric working machine 1 according to an embodiment. FIG. 8 is an exploded rear perspective view of a part of the electric working machine 1 according to an embodiment. In the embodiment, the electric working machine 1 is an impact driver, which is a type of power tool.

[0031] The electric work machine 1 includes a housing 2, a rear case 3, a hammer case 4, a bearing box 5, a motor 6, a fan 7, a rear rotor bearing 8, a front rotor bearing 9, a reduction mechanism 10, a spindle 11, a spindle bearing 12, an impact mechanism 13, a hammer bearing 14, a tool holding shaft 15, a shaft bearing 16, a movable anvil 17, and a tool holding mechanism 18.

[0032] The housing 2 accommodates at least some of the components of the electric operating machine 1. The housing 2 is made of synthetic resin. In this embodiment, the housing 2 is made of nylon. The housing 2 is composed of a pair of half-split housings. The housing 2 includes a left housing 2L and a right housing 2R disposed to the right of the left housing 2L. The left housing 2L and the right housing 2R are fixed together by a plurality of screws (not shown).

[0033] The housing 2 has a storage portion 2A, a grip portion 2B, and a battery holding portion 2C.

[0034] The housing portion 2A is disposed so as to cover the hammer case 4. The housing portion 2A may be disposed so as to cover both the rear case 3 and the hammer case 4. The housing portion 2A is cylindrical.

[0035] The grip portion 2B is held by an operator and extends downward from the housing portion 2A.

[0036] The battery holding portion 2C holds the battery pack 19. A battery attachment portion is provided at the bottom of the battery holding portion 2C. The battery holding portion 2C holds the battery pack 19 via the battery attachment portion. The battery pack 19 is attached to and detached from the battery attachment portion. The battery holding portion 2C is connected to the lower end portion of the grip portion 2B.

[0037] The rear case 3 accommodates at least a part of the motor 6 and the fan 7. The rear case 3 is made of synthetic resin. An example of the synthetic resin from which the rear case 3 is made is nylon resin.

[0038] The rear case 3 has a cylindrical portion 3A, a disk portion 3B, a bearing holding portion 3C, a screw boss portion 3D, and a protruding portion 3E.

[0039] The cylindrical portion 3A is disposed so as to surround the rotation axis AX. The disk portion 3B is disposed so as to cover the opening at the rear end portion of the cylindrical portion 3A.

[0040] The bearing retaining portion 3C is disposed in the center of the front surface of the disk portion 3B. The bearing retaining portion 3C protrudes forward from the front surface of the disk portion 3B. The bearing retaining portion 3C is cylindrical. The rear rotor bearing 8 is retained by the bearing retaining portion 3C.

[0041] The screw boss portion 3D is provided on the outer circumferential surface of the cylindrical portion 3A. Four screw boss portions 3D are provided at intervals in the circumferential direction. An intermediate portion of the screw 20 is disposed in a screw opening 3F provided in the screw boss portion 3D.

[0042] The protrusion 3E protrudes downward from a lower portion of the outer circumferential surface of the cylindrical portion 3A. The protrusion 3E is hooked onto at least a portion of the housing 2. A screw opening 3G is provided in the protrusion 3E. A screw (not shown) inserted into the screw opening 3G is coupled to the housing 2. This suppresses relative movement between the rear case 3 and the housing 2 in the circumferential direction.

[0043] The hammer case 4 houses the reduction mechanism 10, the spindle 11, the striking mechanism 13, the movable anvil 17, the spindle bearing 12, the hammer bearing 14, and the shaft bearing 16. The hammer case 4 is made of metal. Examples of metals that form the hammer case 4 include iron, aluminum, and magnesium.

[0044] The hammer case 4 is cylindrical and has a large cylinder portion 4A, a small cylinder portion 4B, a convex portion 4C, a screw boss portion 4D, and a protruding portion 4E.

[0045] The large cylinder portion 4A and the small cylinder portion 4B are disposed so as to surround the rotation axis AX. The small cylinder portion 4B is disposed forward of the large cylinder portion 4A. The inner diameter of the large cylinder portion 4A is larger than the inner diameter of the small cylinder portion 4B. The outer diameter of the large cylinder portion 4A is larger than the outer diameter of the small cylinder portion 4B. The protrusion 4C protrudes rearward from the rear surface of the large cylinder portion 4A.

[0046] The protrusions 4C are provided at intervals in the circumferential direction. The rear end surfaces of the protrusions 4C come into contact with the front end surface of the tubular portion 3A.

[0047] The screw boss portion 4D is provided on the outer peripheral surface of the large cylinder portion 4A. Four screw boss portions 4D are provided at intervals in the circumferential direction. A front end portion of a screw 20 is inserted into a screw hole 4F provided in the screw boss portion 4D. With the screw 20 inserted into the screw opening 3F of the screw boss portion 3D from the rear of the screw boss portion 3D, the threaded portion provided at the front end portion of the screw 20 is coupled to the screw hole 4F provided in the screw boss portion 4D. By fixing the rear case 3 and the hammer case 4 with the screw 20, relative movement between the rear case 3 and the hammer case 4 is suppressed.

[0048] The protrusion 4E protrudes downward from a lower portion of the outer circumferential surface of the large cylinder portion 4A. The protrusion 4E is hooked onto at least a portion of the housing 2. A screw opening 4G is provided in the protrusion 4E. A screw (not shown) inserted into the screw opening 4G is coupled to the housing 2. This suppresses relative movement between the hammer case 4 and the housing 2 in the circumferential direction.

[0049] The bearing box 5 is disposed so as to cover the opening at the rear end of the large cylindrical portion 4 A. The bearing box 5 holds a spindle bearing 12.

[0050] The bearing box 5 has a large cylinder portion 5A, a small cylinder portion 5B, a front annular portion 5C, a rear annular portion 5D, a protrusion 5E, a rotation preventing portion 5F, and a boss portion 5G.

[0051] The large cylinder portion 5A and the small cylinder portion 5B are disposed so as to surround the rotation axis AX. The small cylinder portion 5B is disposed rearward of the large cylinder portion 5A. The inner diameter of the large cylinder portion 5A is larger than the inner diameter of the small cylinder portion 5B. The outer diameter of the large cylinder portion 5A is larger than the outer diameter of the small cylinder portion 5B.

[0052] The front annular portion 5C is disposed to connect the rear end of the large cylinder portion 5A and the front end of the small cylinder portion 5B. The outer edge of the front annular portion 5C is connected to the rear end of the large cylinder portion 5A. The inner edge of the front annular portion 5C is connected to the front end of the small cylinder portion 5B.

[0053] The rear annular portion 5D is disposed at the rear end of the small tube portion 5B. The outer edge of the rear annular portion 5D is connected to the rear end of the small tube portion 5B.

[0054] The spindle bearing 12 is disposed radially inside the small cylindrical portion 5B. The inner peripheral surface of the small cylindrical portion 5B contacts the outer peripheral surface of the outer ring of the spindle bearing 12. The rear end of the spindle bearing 12 is supported by the front surface of the rear annular portion 5D.

[0055] The protrusions 5E protrude rearward from the peripheral edge of the rear surface of the front annular portion 5C. A plurality of protrusions 5E are provided at intervals in the circumferential direction. The rear end surface of the protrusions 5E contacts the front end surface of the outer core 25, which will be described later.

[0056] The boss portion 5G protrudes rearward from the rear surface of the front annular portion 5C. A plurality of boss portions 5G are provided at intervals in the circumferential direction. The boss portions 5G are integrally formed on the inner surface of the protrusion portion 5E facing radially inward. A pin portion 28C of the insulator 26, which will be described later, is inserted into an insertion hole 5H provided in the boss portion 5G.

[0057] The rear end surface of the protrusion 5E is disposed rearward of the rear end surface of the boss 5G. A recess 5J is provided on the inner surface of the protrusion 5E rearward of the rear end surface of the boss 5G. The recess 5J is provided so as to be recessed radially outward from the inner surface of the protrusion 5E. The recess 5J extends in the front-rear direction. The pin portion 28C is inserted into the insertion hole 5H from the rear of the boss 5G.

[0058] When the pin portion 28C is inserted into the insertion hole 5H, the cylindrical portion 28B, which will be described later, is guided by the recess 5J. After the pin portion 28C is inserted into the insertion hole 5H, the cylindrical portion 28B is supported by the recess 5J. By inserting the pin portion 28C into the insertion hole 5H, relative movement between the bearing box 5 and the stator 21 in both the front-rear direction and the circumferential direction is suppressed.

[0059] The motor 6 is a power source for the electric work machine 1. The motor 6 is an electric motor that is driven based on electric power supplied from a battery pack 19. The motor 6 is an inner rotor type brushless motor.

[0060] The motor 6 has a stator 21 and a rotor 22. The stator 21 is supported by the rear case 3. At least a portion of the rotor 22 is disposed inside the stator 21. The rotor 22 rotates relative to the stator 21. The rotor 22 rotates about a rotation axis AX extending in the front-rear direction.

[0061] Fig. 9 is a front perspective view of the motor 6 according to the embodiment. Fig. 10 is an exploded front perspective view of the motor 6 according to the embodiment. Fig. 11 is an exploded front perspective view of the stator 21 according to the embodiment.

[0062] The stator 21 has a stator core 23, an insulator 26, and a coil 29. The stator core 23 is disposed radially outward of the rotor 22. The stator core 23 includes a plurality of stacked steel plates. The steel plates are metal plates whose main component is iron. The insulator 26 is disposed so as to cover at least a portion of the surface of the stator core 23. The insulator 26 is fixed to the stator core 23. The insulator 26 is an electrical insulating member made of synthetic resin.

[0063] In the embodiment, the stator core 23 includes an inner core 24 and an outer core 25. The outer core 25 is disposed around the inner core 24.

[0064] The inner core 24 includes an inner yoke portion 24A, teeth portions 24B, and connecting portions 24C.

[0065] The inner yoke portion 24A is annular.

[0066] Teeth portion 24B protrudes radially outward from the outer circumferential surface of inner yoke portion 24A. A plurality of teeth portions 24B are provided at intervals in the circumferential direction.

[0067] The connecting portion 24C is connected to the radial outer end of the tooth portion 24B. In the circumferential direction, the dimension of the connecting portion 24C is larger than the dimension of the tooth portion 24B. The connecting portion 24C is provided so as to protrude from the radial outer end of the tooth portion 24B to one circumferential side and the other circumferential side.

[0068] The outer core 25 is substantially annular. A recess 25A is provided in the inner circumferential surface of the outer core 25 on the radially inner side, in which at least a part of the connecting portion 24C is disposed.

[0069] At least a portion of connecting portion 24C is disposed in recess 25A, thereby connecting inner core 24 and outer core 25. When inner core 24 and outer core 25 are connected and integrated with each other, stator core 23 is formed.

[0070] In the embodiment, the insulator 26 includes a rear insulator 27 and a front insulator 28. The rear insulator 27 is fixed to a rear portion of the stator core 23. The front insulator 28 is fixed to a front portion of the stator core 23. The insulator 26 is disposed so as to cover a surface of the inner core 24.

[0071] The rear insulator 27 has a rear plate portion 27A that contacts the rear end surface of the outer core 25. A plurality of rear plate portions 27A are provided at intervals in the circumferential direction. The rear plate portions 27A are disposed radially outward from the coil 29. The rear plate portions 27A support an outer periphery of the coil 29 that faces radially outward.

[0072] The front insulator 28 has a support plate portion 28D that supports an outer periphery of the coil 29, a front plate portion 28A that contacts the front end surface of the inner core 24, a cylindrical portion 28B that protrudes forward from the front surface of the front plate portion 28A, and a pin portion 28C that protrudes forward from the front end portion of the cylindrical portion 28B. A plurality of support plate portions 28D are provided at intervals in the circumferential direction. Each of the front plate portion 28A and the cylindrical portion 28B is fixed to an outer surface of the support plate portion 28D that faces radially outward. The pin portion 28C is disposed forward of the front end portion of the support plate portion 28D. The thickness of the pin portion 28C is thinner than the thickness of the cylindrical portion 28B.

[0073] The coil 29 is attached to the stator core 23 via the insulator 26. A plurality of coils 29 are arranged. The coils 29 are arranged around the teeth portion 24B via the rear insulator 27 and the front insulator 28. The coils 29 and the stator core 23 are electrically insulated by the insulator 26. The plurality of coils 29 are connected to each other via a jumper wire 30. Current from the battery pack 19 is supplied to the coils 29 via a fusing terminal 31 and the jumper wire 30.

[0074] The rotor 22 rotates about a rotation axis AX. The rotor 22 includes a rotor magnet 32 ​​and a rotor shaft 33.

[0075] The rotor shaft 33 is made of steel. The rotor magnet 32 ​​is fixed to the rotor shaft 33. The rotor magnet 32 ​​is cylindrical. The rotor shaft 33 is disposed radially inward of the rotor magnet 32.

[0076] The rotor shaft 33 has a magnet fixing portion 33A to which the rotor magnet 32 ​​is fixed, a fan fixing portion 33B arranged rearward of the rear end surface of the rotor magnet 32, a rear support portion 33C protruding rearward from the rear end surface of the fan fixing portion 33B, and a front support portion 33D arranged forward of the front end surface of the rotor magnet 32.

[0077] The diameter of the fan fixing portion 33B is larger than the diameter of the magnet fixing portion 33A. The diameters of the rear support portion 33C and the front support portion 33D are each smaller than the diameter of the magnet fixing portion 33A. The diameter of the rear support portion 33C is smaller than the diameter of the front support portion 33D.

[0078] A rear support portion 33C of the rotor shaft 33 is rotatably supported by a rear rotor bearing 8. A front support portion 33D of the rotor shaft 33 is rotatably supported by a front rotor bearing 9. The rear rotor bearing 8 is held by a bearing holding portion 3C of the rear case 3. The front rotor bearing 9 is held by the spindle 11. A front end portion of the rotor shaft 33 is disposed inside the spindle 11.

[0079] A pinion gear is fixed to a front end of the rotor shaft 33. The pinion gear is connected to at least a part of the reduction gear mechanism 10. The rotor shaft 33 is connected to the reduction gear mechanism 10 via the pinion gear .

[0080] The fan 7 generates an airflow for cooling the motor 6. The fan 7 is disposed rearward of the motor 6. The fan 7 is fixed to a fan fixing portion 33B of the rotor shaft 33 via a bush 7A. The fan 7 rotates due to the rotation of the rotor 22. As the rotor shaft 33 rotates, the fan 7 rotates together with the rotor shaft 33. The rotation of the fan 7 generates an airflow around the motor 6, thereby cooling the motor 6.

[0081] The speed reduction mechanism 10 connects the rotor shaft 33 and the spindle 11. The speed reduction mechanism 10 transmits the rotation of the rotor 22 to the spindle 11. The speed reduction mechanism 10 rotates the spindle 11 at a rotational speed lower than the rotational speed of the rotor shaft 33. The speed reduction mechanism 10 includes a planetary gear mechanism.

[0082] Fig. 12 is an exploded perspective view from the front showing a part of the electric working machine 1 according to the embodiment. Fig. 13 is an exploded perspective view from the rear showing a part of the electric working machine 1 according to the embodiment.

[0083] The reduction mechanism 10 has a plurality of planetary gears 58 arranged around the pinion gear 48, pins 59 supporting each of the planetary gears 58, and an internal gear 60 arranged around the planetary gears 58. Each of the planetary gears 58 meshes with the pinion gear 48. The planetary gears 58 are rotatably supported by the spindle 11 via the pins 59. The spindle 11 is rotated by the planetary gears 58. The internal gear 60 has internal teeth that mesh with the planetary gears 58.

[0084] The internal gear 60 is fixed to the bearing box 5. As shown in Figs. 7 and 8, a protrusion 62 is provided on the outer surface of the internal gear 60. The protrusion 62 protrudes radially outward from the outer circumferential surface of the internal gear 60. A plurality of the protrusions 62 are provided at intervals in the circumferential direction. As described above, the bearing box 5 has a plurality of rotation stoppers 5F arranged at intervals in the circumferential direction. A recess 5K is formed between a pair of adjacent rotation stoppers 5F. The protrusion 62 is arranged in the recess 5K. By arranging the protrusion 62 in the recess 5K, relative rotation between the bearing box 5 and the internal gear 60 is suppressed. The bearing box 5 is fixed to each of the rear case 3 and the hammer case 4 via the front insulator 28. The internal gear 60 is always unable to rotate with respect to the hammer case 4 and the rear case 3.

[0085] When the rotor shaft 33 is rotated by the drive of the motor 6, the pinion gear 48 rotates, and the planetary gear 58 revolves around the pinion gear 48. The planetary gear 58 revolves while meshing with the internal teeth of the internal gear 60. Due to the revolution of the planetary gear 58, the spindle 11 connected to the planetary gear 58 via the pin 59 rotates at a rotational speed lower than the rotational speed of the rotor shaft 33.

[0086] The spindle 11 rotates due to the rotational force of the motor 6. At least a portion of the spindle 11 is disposed forward of the reduction mechanism 10. The spindle 11 is disposed rearward of the tool holding shaft 15. The spindle 11 rotates due to the rotor 22. The spindle 11 rotates due to the rotational force of the rotor 22 transmitted by the reduction mechanism 10. The spindle 11 transmits the rotational force of the motor 6 to the tool holding shaft 15 via the impact mechanism 13.

[0087] The spindle 11 has a spindle shaft portion 11A, a flange portion 11B, a pin support portion 11C, a connecting portion 11D, and a protruding portion 11E.

[0088] The spindle shaft portion 11A extends in the axial direction. The spindle shaft portion 11A is disposed so as to surround the rotation axis AX. A spindle protrusion 69 is provided at the front end of the outer peripheral surface of the spindle shaft portion 11A. The spindle protrusion 69 protrudes radially outward from the front end of the outer peripheral surface of the spindle shaft portion 11A. Two spindle protrusions 69 are provided around the rotation axis AX. The two spindle protrusions 69 are disposed so as to sandwich the rotation axis AX. In the following description, one of the spindle protrusions 69 is appropriately referred to as a first spindle protrusion 691, and the other spindle protrusion 69 is appropriately referred to as a second spindle protrusion 692.

[0089] A ball groove 70 is formed on the outer circumferential surface of the spindle shaft portion 11A. The ball groove 70 is disposed rearward of the spindle protrusion portion 69. The ball groove 70 is formed so as to surround the rotation axis AX. The ball groove 70 is formed so as to be recessed radially inward from the outer circumferential surface of the spindle shaft portion 11A.

[0090] The flange portion 11B is provided at the rear of the spindle shaft portion 11A. The flange portion 11B protrudes radially outward from the rear of the spindle shaft portion 11A. A spindle groove 71 is provided on the front surface of the flange portion 11B. A plurality of spindle grooves 71 are provided in the circumferential direction. In this embodiment, three spindle grooves 71 are provided in the circumferential direction.

[0091] The pin support portion 11C is disposed rearward of the flange portion 11B. The pin support portion 11C is annular. A part of the flange portion 11B and a part of the pin support portion 11C are connected via a connecting portion 11D. The convex portion 11E protrudes rearward from the pin support portion 11C.

[0092] Planetary gear 58 is disposed between flange portion 11B and pin support portion 11C. A front end portion of pin 59 is supported by flange portion 11B. A rear end portion of pin 59 is supported by pin support portion 11C. Planetary gear 58 is rotatably supported by each of flange portion 11B and pin support portion 11C via pin 59.

[0093] The protrusion 11E is disposed inside the spindle bearing 12. The protrusion 11E is rotatably supported by the spindle bearing 12. A washer 74 is disposed at a position facing the front end of the inner ring of the spindle bearing 12.

[0094] The spindle bearing 12 is disposed radially inside the stator 21. The spindle bearing 12 and at least a portion of the stator 21 overlap in the front-rear direction.

[0095] In the embodiment, the spindle bearing 12 is disposed radially inside the front insulator 28 of the insulator 26. The spindle bearing 12 and at least a portion of the front insulator 28 overlap in the front-rear direction. The spindle bearing 12 and at least a portion of the coil 29 overlap in the front-rear direction. The spindle bearing 12 is disposed forward of the stator core 23. Note that the spindle bearing 12 and the front end portion of the stator core 23 may overlap in the front-rear direction.

[0096] The striking mechanism 13 is driven by the motor 6. The rotational force of the motor 6 is transmitted to the striking mechanism 13 via the reduction mechanism 10 and the spindle 11. The striking mechanism 13 strikes the movable anvil 17 in the rotational direction based on the rotational force of the spindle 11 rotated by the motor 6.

[0097] The striking mechanism 13 includes a hammer 75 , a cam ring 76 , a ball 77 , an elastic member 78 , a washer 79 , and a rotating ball 80 .

[0098] The hammer 75 strikes the movable anvil 17 in the rotational direction. The hammer 75 strikes the tool holding shaft 15 in the rotational direction via the movable anvil 17. The hammer 75 is supported by the spindle 11. The hammer 75 is disposed around the spindle shaft portion 11A. The hammer 75 is rotatably supported by the spindle shaft portion 11A. The hammer 75 is disposed forward of the reduction mechanism 10.

[0099] The hammer 75 does not move in the axial direction relative to the hammer case 4. In reality, the hammer 75 may move slightly in the axial direction relative to the hammer case 4 due to, for example, rattle. The hammer 75 can rotate relatively to the spindle 11. The hammer 75 can rotate relatively to the spindle shaft portion 11A while being supported by the spindle shaft portion 11A. The hammer 75 strikes the movable anvil 17 in the rotational direction without being displaced in the axial direction relative to the spindle 11.

[0100] The hammer 75 has a rear outer cylinder portion 81, a front outer cylinder portion 82, and an inner cylinder portion 83. The rear outer cylinder portion 81, the front outer cylinder portion 82, and the inner cylinder portion 83 are arranged to surround the rotation axis AX. The rear outer cylinder portion 81, the front outer cylinder portion 82, and the inner cylinder portion 83 are integral with each other.

[0101] The front outer cylinder portion 82 is disposed forward of the rear outer cylinder portion 81. The front end portion of the rear outer cylinder portion 81 is connected to the rear end portion of the front outer cylinder portion 82. The outer diameter of the rear outer cylinder portion 81 is larger than the outer diameter of the front outer cylinder portion 82. The inner diameter of the rear outer cylinder portion 81 is larger than the inner diameter of the front outer cylinder portion 82.

[0102] The inner cylinder portion 83 is supported by the spindle shaft portion 11A. The inner cylinder portion 83 is disposed radially inward from the rear outer cylinder portion 81 and the front outer cylinder portion 82. The front end portion of the inner cylinder portion 83 is connected to the rear end portion of the front outer cylinder portion 82. The front outer cylinder portion 82 is disposed radially outward and forward from the inner cylinder portion 83. The rear outer cylinder portion 81 is disposed radially outward from the inner cylinder portion 83 and the front outer cylinder portion 82, and is disposed rearward from the front outer cylinder portion 82.

[0103] A hammer protrusion 84 is provided on the inner peripheral surface of the front outer cylinder portion 82. The hammer protrusion 84 protrudes radially inward from the inner peripheral surface of the front outer cylinder portion 82. Two hammer protrusions 84 are provided around the rotation axis AX. The two hammer protrusions 84 are arranged to sandwich the rotation axis AX. The two hammer protrusions 84 are arranged to face each other. In the following description, one hammer protrusion 84 will be appropriately referred to as a first hammer protrusion 841, and the other hammer protrusion 84 will be appropriately referred to as a second hammer protrusion 842.

[0104] The inner cylinder portion 83 is disposed around the spindle shaft portion 11A. The inner peripheral surface of the inner cylinder portion 83 faces the outer peripheral surface of the spindle shaft portion 11A. A ball groove 85 is formed on the inner peripheral surface of the inner cylinder portion 83. The ball groove 85 is formed so as to surround the rotation axis AX. The ball groove 85 is formed so as to be recessed radially outward from the inner peripheral surface of the inner cylinder portion 83.

[0105] A guide groove 86 is provided on the inner peripheral surface of the rear outer cylinder portion 81. The guide groove 86 is formed to extend in the axial direction on the inner peripheral surface of the rear outer cylinder portion 81. The guide groove 86 is formed to extend forward from the rear end portion of the rear outer cylinder portion 81. A plurality of guide grooves 86 are provided at intervals around the rotation axis AX of the hammer 75. In this embodiment, six guide grooves 86 are provided around the rotation axis AX. The six guide grooves 86 are provided at equal intervals in the circumferential direction.

[0106] The cam ring 76 is connected to the flange portion 11B via balls 77 so as to be relatively rotatable. The cam ring 76 is connected to the hammer 75 so as to be relatively movable in the axial direction but not rotatable relative to the hammer. The cam ring 76 is disposed so as to face the front surface of the flange portion 11B. The cam ring 76 is connected to the rear portion of the hammer.

[0107] The cam ring 76 is disposed inside the rear outer cylinder portion 81. The cam ring 76 and the hammer 75 can move relative to each other in the axial direction. As described above, the hammer 75 does not move axially relative to the hammer case 4. Note that, in reality, the hammer 75 may move slightly in the axial direction relative to the hammer case 4 due to, for example, rattle. The cam ring 76 moves axially relative to the hammer case 4 inside the rear outer cylinder portion 81 of the hammer 75.

[0108] Cam slide portions 87 are provided on the outer peripheral surface of the cam ring 76. The cam slide portions 87 protrude radially outward from the outer peripheral surface of the cam ring 76. A plurality of cam slide portions 87 are provided at intervals around the rotation axis AX of the cam ring 76. Six cam slide portions 87 are provided around the rotation axis AX. The six cam slide portions 87 are provided at equal intervals in the circumferential direction. The cam slide portions 87 are disposed in the guide grooves 86. One cam slide portion 87 is disposed in one guide groove 86. The cam slide portions 87 move in the guide grooves 86 in the axial direction. The cam ring 76 can move in the axial direction relative to the hammer 75 while being guided by the guide grooves 86 via the cam slide portions 87.

[0109] The guide groove 86 of the hammer 75 guides the cam ring 76 in the axial direction and functions as a guide portion that suppresses relative rotation between the hammer 75 and the cam ring 76 .

[0110] Cam grooves 88 are provided on the inner circumferential surface of the cam ring 76. A plurality of cam grooves 88 are provided in the circumferential direction. In this embodiment, three cam grooves 88 are provided in the circumferential direction.

[0111] The cam ring 76 is disposed forward of the flange portion 11 B. The cam ring 76 is disposed inside the rear outer cylinder portion 81 of the hammer 75 so as to face the front surface of the flange portion 11 B.

[0112] The ball 77 is disposed between the spindle 11 and the cam ring 76. The ball 77 is disposed between the flange portion 11B and the cam ring 76. The flange portion 11B of the spindle 11 and the cam ring 76 can rotate relative to each other via the ball 77.

[0113] The ball 77 is made of a metal such as steel. The flange portion 11B has a spindle groove 71 in which at least a portion of the ball 77 is disposed. The spindle groove 71 is provided in a part of the front surface of the flange portion 11B. In a plane perpendicular to the rotation axis AX, the spindle groove 71 is arc-shaped. The cam ring 76 has a cam groove 88 in which at least a portion of the ball 77 is disposed. The cam groove 88 is provided in a part of the inner peripheral surface of the cam ring 76. In a plane perpendicular to the rotation axis AX, the cam groove 88 is arc-shaped. The ball 77 is disposed between the spindle groove 71 and the cam groove 88. As described above, three spindle grooves 71 are provided. Three cam grooves 88 are provided. Three balls 77 are provided. One ball 77 is disposed between one spindle groove 71 and one cam groove 88. The balls 77 can roll inside the spindle groove 71 and inside the cam groove 88. The cam ring 76 can move together with the balls 77.

[0114] At least a portion of the spindle groove 71 is inclined rearward toward one circumferential side. At least a portion of the spindle groove 71 may be inclined rearward toward the other circumferential side.

[0115] At least a portion of the cam groove 88 is inclined rearward toward one circumferential side. At least a portion of the cam groove 88 may be inclined rearward toward the other circumferential side.

[0116] During relative rotation between flange portion 11B and cam ring 76, ball 77 moves between spindle groove 71 and cam groove 88 from the center of spindle groove 71 toward one circumferential end, causing cam ring 76 to receive force from ball 77 and move forward.

[0117] In addition, during relative rotation between flange portion 11B and cam ring 76, ball 77 moves between spindle groove 71 and cam groove 88 from one circumferential end toward the center of spindle groove 71, causing cam ring 76 to receive force from ball 77 and move rearward.

[0118] During relative rotation between flange portion 11B and cam ring 76, ball 77 moves between spindle groove 71 and cam groove 88 from the center of spindle groove 71 toward the other circumferential end, causing cam ring 76 to receive force from ball 77 and move forward.

[0119] In addition, during relative rotation between flange portion 11B and cam ring 76, ball 77 moves between spindle groove 71 and cam groove 88 from the other circumferential end toward the center of spindle groove 71, causing cam ring 76 to receive force from ball 77 and move rearward.

[0120] The flange portion 11B of the spindle 11 and the cam ring 76 can move relative to each other in the axial direction and the rotational direction within a movable range defined by the spindle groove 71 and the cam groove 88.

[0121] The cam ring 76 is connected to the flange portion 11B of the spindle 11 via balls 77. The cam ring 76 can rotate together with the spindle 11 based on the rotational force of the spindle 11 rotated by the motor 6. The cam ring 76 rotates about the rotation axis AX.

[0122] The elastic member 78 constantly generates an elastic force that moves the cam ring 76 backward. In the axial direction, the elastic member 78 is disposed between the hammer 75 and the cam ring 76. At least a part of the elastic member 78 is disposed around the spindle shaft portion 11A. In the embodiment, the hammer 75 has a recess 89 formed so as to be recessed forward from the rear surface of the hammer 75. The recess 89 is defined by the inner peripheral surface of the rear outer cylinder portion 81, the outer peripheral surface of the inner cylinder portion 83, and a support surface 90 disposed forward of the flange portion 11B and the cam ring 76. The support surface 90 is disposed so as to connect the front end of the inner peripheral surface of the rear outer cylinder portion 81 and the front end of the outer peripheral surface of the inner cylinder portion 83. The support surface 90 is annular. At least a part of the elastic member 78 is disposed inside the recess 89. In the axial direction, the elastic member 78 is disposed between the front surface of the cam ring 76 and a support surface 90 of the hammer 75 that is disposed forward of the flange portion 11B and the cam ring 76 .

[0123] In the embodiment, a rear portion of the elastic member 78 is disposed around the spindle shaft portion 11A. A front portion of the elastic member 78 is disposed around the inner tube portion 83 inside the recess 89. In the embodiment, the elastic member 78 includes a plurality of disc springs 91. The plurality of disc springs 91 are disposed in the axial direction. In the embodiment, four disc springs 91 are disposed in the axial direction. The disc springs 91 are annular. In the embodiment, some of the disc springs 91 are disposed around the spindle shaft portion 11A, and some of the disc springs 91 are disposed around the inner tube portion 83.

[0124] The hammer 75 is disposed around the spindle shaft portion 11A. The cam ring 76 is disposed forward of the flange portion 11B and is connected to the flange portion 11B via a ball 77. The cam ring 76 is connected to the rear of the hammer 75 via a cam slide portion 87 and a guide groove 86. A closed space is defined by the spindle shaft portion 11A, the hammer 75, and the cam ring 76. The closed space is defined by the outer peripheral surface of the spindle shaft portion 11A, the outer peripheral surface of the inner cylinder portion 83, the support surface 90, the inner peripheral surface of the rear outer cylinder portion 81, and the front surface of the cam ring 76. The elastic member 78 is disposed in the closed space.

[0125] The washer 79 supports a front end of the elastic member 78. The washer 79 is disposed radially outward from the inner cylindrical portion 83. The washer 79 is annular. The washer 79 is disposed so as to surround the inner cylindrical portion 83. The washer 79 is disposed inside the recessed portion 89. The washer 79 is supported by at least a portion of the hammer 75 inside the recessed portion 89.

[0126] The rear end of the elastic member 78 contacts the front surface of the cam ring 76. The front end of the elastic member 78 contacts the washer 79. The front end of the elastic member 78 is connected to the hammer 75 via the washer 79. In the embodiment, the rear end of the elastic member 78 refers to the rear end of the disc spring 91 that is located at the rearmost position among the multiple disc springs 91 arranged in the axial direction. The front end of the elastic member 78 refers to the front end of the disc spring 91 that is located at the frontmost position among the multiple disc springs 91 arranged in the axial direction.

[0127] The rotating ball 80 is disposed between the spindle shaft portion 11A and the hammer 75. The rotating ball 80 is disposed between the ball groove 70 and the ball groove 85. A portion of the rotating ball 80 is disposed in the ball groove 70, and a portion of the rotating ball 80 is disposed in the ball groove 85. A plurality of rotating balls 80 are disposed around the rotation axis AX of the spindle 11. As described above, the hammer 75 can rotate relative to the spindle shaft portion 11A. The rotating ball 80 functions as a bearing for the hammer 75. The rotating ball 80 allows the hammer 75 and the spindle shaft portion 11A to rotate smoothly relative to each other.

[0128] In the embodiment, a screw 93 is provided for adjusting the elastic force of the elastic member 78 in the initial state before the motor 6 is started. The screw 93 adjusts the elastic force of the elastic member 78 by adjusting the amount of compression of the elastic member 78 in the initial state.

[0129] The rear end of the elastic member 78 is supported by the flange portion 11B via the cam ring 76. The screw 93 adjusts the amount of compression of the elastic member 78 by moving the position of the front end of the elastic member 78.

[0130] The screw 93 contacts the washer 79. The screw 93 is connected to the front end of the elastic member 78 via the washer 79. The screw 93 is disposed in a screw hole 94 formed in the hammer 75. The screw hole 94 is formed so as to penetrate a front end surface 95 of the rear outer cylinder portion 81 and the support surface 90. In a plane perpendicular to the rotation axis AX, the front end surface 95 is annular. The front end surface 95 faces forward. A plurality of screw holes 94 are formed around the rotation axis AX of the hammer 75 at intervals. One screw 93 is disposed in each of the plurality of screw holes 94. In the embodiment, six screw holes 94 are formed around the rotation axis AX at intervals. One screw 93 is disposed in each of the six screw holes 94.

[0131] The rear end of the screw 93 contacts the front surface of the washer 79. The rotation of the screw 93 adjusts the compression amount of the elastic member 78. When the screw 93 rotates in one direction, the screw 93 moves backward relative to the hammer 75. When the screw 93 moves backward, the front end of the elastic member 78 moves backward via the washer 79. When the rear end of the elastic member 78 is supported by the flange portion 11B via the cam ring 76, the front end of the elastic member 78 moves backward, compressing the elastic member 78. When the screw 93 rotates in the other direction, the screw 93 moves forward relative to the hammer 75. When the rear end of the elastic member 78 is supported by the flange portion 11B via the cam ring 76, the front end of the elastic member 78 moves forward, expanding the elastic member 78.

[0132] The adjustment of the compression amount of the elastic member 78 is performed during the assembly work of the electric work machine 1. After the spindle 11, the hammer 75, and the cam ring 76 are connected so that the elastic member 78 is disposed in a closed space defined by the spindle shaft portion 11A, the hammer 75, and the cam ring 76, a screw tightening tool is inserted into the screw hole 94 from the front of the front end face 95. The tip of the screw tightening tool is inserted into the tool hole of the screw 93 via the screw hole 94. An assembler can adjust the compression amount of the elastic member 78 by rotating the screw 93 using the screw tightening tool. Also, the axial position of each of the multiple screws 93 is adjusted, thereby adjusting the inclination angle of the elastic member 78 with respect to the spindle 11.

[0133] The hammer bearing 14 rotatably supports the hammer 75. The hammer bearing 14 is held by the hammer case 4. The hammer bearing 14 is disposed around the hammer 75. In the embodiment, the hammer bearing 14 rotatably supports the front end of the hammer 75. In the embodiment, the hammer bearing 14 is disposed around the front outer cylinder portion 82. At least a part of the rear end of the hammer bearing 14 contacts the front end surface 95 of the rear outer cylinder portion 81. The hammer case 4 has an opposing surface 96 that faces the front end of the hammer bearing 14. The opposing surface 96 faces rearward. The front end of the hammer bearing 14 and the opposing surface 96 of the hammer case 4 face each other via a gap. The hammer bearing 14 is a ball bearing. The outer ring of the hammer bearing 14 contacts the inner circumferential surface of the large cylinder portion 4A of the hammer case 4. The inner ring of the hammer bearing 14 contacts the outer circumferential surface of the front outer cylinder portion 82 of the hammer 75 .

[0134] In the embodiment, the hammer bearing 14 is disposed so as to cover the front end of the screw hole 94. In the assembly work of the electric operating machine 1, the screw 93 is turned with a screw tightening tool to adjust the compression amount of the elastic member 78, and then the hammer bearing 14 is disposed around the front outer cylinder portion 82.

[0135] The tool holding shaft 15 is an output part of the electric work machine 1 that rotates based on the rotational force of the rotor 22. At least a part of the tool holding shaft 15 is disposed forward of the spindle 11. The tool holding shaft 15 has a tool holding part 97 and an anvil part 98 disposed rearward of the tool holding part 97. The tool holding part 97 is rod-shaped and extends in the front-rear direction. The anvil part 98 is connected to the rear part of the tool holding part 97.

[0136] The tool holding portion 97 holds a tool bit. The tool holding portion 97 has a tool hole 99 into which the tool bit is inserted. The tool hole 99 is formed so as to extend rearward from the front end surface of the tool holding portion 97. The tool bit is attached to the tool holding shaft 15.

[0137] The anvil portion 98 is disposed rearward of the tool holding portion 97. The anvil portion 98 is connected to the rear portion of the tool holding portion 97. The anvil portion 98 is disposed so as to surround the rotation axis AX. The anvil portion 98 has a recess 100 into which the front end portion of the spindle shaft portion 11A is inserted. The front end portion of the spindle shaft portion 11A, including the spindle protrusion portion 69, is disposed inside the recess 100. The recess 100 is formed so as to be recessed forward from the rear end surface of the anvil portion 98.

[0138] The anvil portion 98 has an anvil hole 104 penetrating an outer peripheral surface 103 of the anvil portion 98 and an inner peripheral surface 101 of the anvil portion 98. The anvil hole 104 is formed to extend in the radial direction. Two anvil holes 104 are provided around the rotation axis AX. The two anvil holes 104 are arranged to sandwich the rotation axis AX.

[0139] In the embodiment, a support ball 106 is supported on the front end of the spindle shaft portion 11A. A support recess 105 is provided on the front end surface of the spindle shaft portion 11A. The inner surface of the support recess 105 is semispherical. The support ball 106 is disposed in the support recess 105. The support ball 106 contacts an opposing surface of the inner surface of the recess 100 facing rearward.

[0140] The tool holding shaft 15 is rotatably supported by a shaft bearing 16. The shaft bearing 16 is arranged around the tool holding portion 97. The shaft bearing 16 is arranged inside the small cylindrical portion 4B of the hammer case 4. The shaft bearing 16 is held in the small cylindrical portion 4B of the hammer case 4. The shaft bearing 16 rotatably supports the front portion of the tool holding portion 97. In the embodiment, two shaft bearings 16 are arranged in the axial direction. An O-ring 107 is arranged between the shaft bearing 16 and the tool holding portion 97.

[0141] A suppressing member 108 that suppresses the shaft bearing 16 from slipping out rearward is disposed behind the shaft bearing 16. The suppressing member 108 is disposed in a groove formed on the inner peripheral surface of the small cylinder portion 4B. Examples of the suppressing member 108 include a snap ring or a C-ring. The suppressing member 108 is disposed so as to contact the rear end surface of the shaft bearing 16. The suppressing member 108 suppresses the shaft bearing 16 from slipping out rearward from the small cylinder portion 4B.

[0142] The movable anvil 17 is movably supported on the tool holder shaft 15. In this embodiment, the movable anvil 17 moves only in the radial direction relative to the tool holder shaft 15. The movable anvil 17 does not move in the axial or radial directions relative to the tool holder shaft 15.

[0143] The movable anvil 17 is movably supported by the anvil portion 98. The movable anvil 17 is disposed in the anvil hole 104. One movable anvil 17 is disposed in each of the two anvil holes 104. The movable anvil 17 is a cylindrical (pin-shaped) member. The movable anvil 17 is disposed in the anvil hole 104 so that the central axis of the movable anvil 17 and the rotation axis AX of the tool holding shaft 15 are parallel to each other. In the following description, one movable anvil 17 will be appropriately referred to as the first movable anvil 171, and the other movable anvil 17 will be appropriately referred to as the second movable anvil 172.

[0144] The movable anvil 17 can move in the radial direction while being guided by the anvil hole 104. The inner surface of the anvil hole 104 functions as a guide surface that guides the movable anvil 17 in the radial direction. The front end of the spindle shaft portion 11A is positioned in the recess 100 of the anvil portion 98. The spindle protrusion 69 is positioned at the front end of the spindle shaft portion 11A. When the spindle protrusion 69 comes into contact with the movable anvil 17, the movable anvil 17 moves radially outward. When the spindle protrusion 69 moves away from the movable anvil 17, the movable anvil 17 moves radially inward.

[0145] The movable anvil 17 moves so as to change between a first state in which at least a part of the movable anvil 17 protrudes radially outward from the outer circumferential surface 103 of the anvil portion 98 of the tool holder shaft 15, and a second state in which the movable anvil 17 is disposed radially inward from the outer circumferential surface 103 of the anvil portion 98 of the tool holder shaft 15. When the spindle 11 rotates, the spindle protrusion 69 comes into contact with the movable anvil 17, causing the movable anvil 17 to change from the second state to the first state. In other words, when the spindle protrusion 69 comes into contact with the movable anvil 17, at least a part of the movable anvil 17 is disposed radially outward from the outer circumferential surface 103 of the anvil portion 98.

[0146] When the movable anvil 17 is in the first state, the hammer protrusion 84 of the hammer 75 can come into contact with the movable anvil 17. The hammer 75 strikes the movable anvil 17 when the movable anvil 17 is in the first state. When the movable anvil 17 is in the second state, the hammer protrusion 84 of the hammer 75 cannot come into contact with the movable anvil 17. The hammer 75 rotates around the spindle shaft portion 11A when the movable anvil 17 is in the second state.

[0147] The tool holding mechanism 18 is disposed around the tool holding portion 97, forward of the hammer case 4. The tool holding mechanism 18 holds a tool tip inserted into a tool hole 99 of the tool holding portion 97. The tool holding mechanism 18 is capable of attaching and detaching the tool tip.

[0148] The tool holding mechanism 18 includes a holding ball 110 , a leaf spring 111 , a sleeve 112 , a coil spring 113 , and a positioning member 114 .

[0149] The tool holding portion 97 has a support recess 115 that supports the holding ball 110. The support recess 115 is formed on the outer surface of the tool holding portion 97. In this embodiment, two support recesses 115 are formed in the tool holding portion 97.

[0150] The retaining balls 110 are movably supported by the tool holding portion 97. The retaining balls 110 are arranged in the support recesses 115. One retaining ball 110 is arranged in each support recess 115.

[0151] A through hole is formed in the tool holding portion 97, connecting the inner surface of the support recess 115 and the inner surface of the tool hole 99. The diameter of the retaining ball 110 is smaller than the diameter of the innermost part of the through hole in the radial direction. With the retaining ball 110 supported by the support recess 115, it is disposed inside the tool hole 99 via at least a part of the retaining ball 110. The retaining ball 110 can fix a tool bit inserted into the tool hole 99. The retaining ball 110 is movable between an engagement position for fixing the tool bit and a release position for releasing the fixation of the tool bit.

[0152] The leaf spring 111 generates an elastic force that moves the retaining ball 110 to the engagement position. The leaf spring 111 is disposed around the tool retaining portion 97. The leaf spring 111 generates an elastic force that moves the retaining ball 110 forward.

[0153] The sleeve 112 is a cylindrical member. The sleeve 112 is disposed around the tool holding portion 97. The sleeve 112 is axially movable around the tool holding portion 97. The sleeve 112 can prevent the retaining ball 110, which is disposed at the engagement position, from escaping from the engagement position. The sleeve 112 can be moved in the axial direction to change the retaining ball 110 to a state where it can be moved from the engagement position to the release position.

[0154] The sleeve 112 is movable around the tool holding portion 97 between a blocking position where the retaining ball 110 is prevented from moving radially outward and an allowing position where the retaining ball 110 is allowed to move radially outward.

[0155] By disposing the sleeve 112 in the blocking position, the retaining ball 110, which is disposed in the engagement position, is prevented from moving radially outward. In other words, by disposing the sleeve 112 in the blocking position, the retaining ball 110, which is disposed in the engagement position, is prevented from escaping from the engagement position. By disposing the sleeve 112 in the blocking position, the bit is maintained in a state where it is fixed by the retaining ball 110.

[0156] By moving the sleeve 112 to the permissible position, the retaining ball 110 disposed at the engagement position is permitted to move radially outward. By moving the sleeve 112 to the permissible position, the retaining ball 110 is changed to a state in which it can be moved from the engagement position to the release position. In other words, by placing the sleeve 112 at the permissible position, the retaining ball 110 disposed at the engagement position is permitted to escape from the engagement position. By placing the sleeve 112 at the permissible position, the state in which the tool bit is fixed by the retaining ball 110 can be released.

[0157] The coil spring 113 generates an elastic force to move the sleeve 112 to the blocking position. The coil spring 113 is disposed around the tool holding portion 97. The blocking position is set rearward of the allowable position. The coil spring 113 generates an elastic force to move the sleeve 112 rearward.

[0158] The positioning member 114 is a ring-shaped member fixed to the outer surface of the tool holding portion 97. The positioning member 114 is fixed at a position capable of facing the rear end portion of the sleeve 112. The positioning member 114 positions the sleeve 112 at the blocking position. The sleeve 112, which is given an elastic force from the coil spring 113 to move rearward, comes into contact with the positioning member 114, and is positioned at the blocking position.

[0159] [Operation of electric work equipment] Next, the operation of the electric working machine 1 will be described. Each of Fig. 14 to Fig. 23 is a cross-sectional view showing the operation of the electric working machine 1 according to this embodiment. Each of Fig. 14, Fig. 16, Fig. 18, Fig. 20, and Fig. 22 is a cross-sectional view passing through the movable anvil 17. Each of Fig. 15, Fig. 17, Fig. 19, Fig. 21, and Fig. 23 is a cross-sectional view passing through the cam ring 76.

[0160] In the embodiment, the spindle projection 69 includes a first spindle projection 691 and a second spindle projection 692. The hammer projection 84 includes a first hammer projection 841 and a second hammer projection 842. The movable anvil 17 includes a first movable anvil 171 and a second movable anvil 172.

[0161] When performing a screw tightening operation on a work object, a tool tip (driver bit) to be used for the screw tightening operation is inserted into the tool hole 99 of the tool holding shaft 15. The tool tip inserted into the tool hole 99 is held by the tool holding mechanism 18.

[0162] In a screw tightening operation, the operator operates the forward / reverse switching lever 41 (see Figs. 1 and 2) provided on the upper part of the grip part 2B so that the tool holding shaft 15 rotates in the forward direction. By operating the forward / reverse switching lever 41, the rotation direction of the motor 6 is switched from one of the forward direction and the reverse direction to the other. By switching the rotation direction of the motor 6, the rotation direction of the spindle 11 is switched.

[0163] After the tool tip is attached to the tool holding shaft 15, the operator holds the grip portion 2B with, for example, his right hand and pulls the trigger lever 40 (see Figs. 1 and 2) provided at the front of the upper part of the grip portion 2B with the index finger of his right hand. When the trigger lever 40 is pulled, power is supplied from the battery pack 19 to the motor 6, and the motor 6 is started. When the motor 6 is started, the rotor shaft 33 of the rotor 22 rotates. When the rotor shaft 33 rotates, the rotational force of the rotor shaft 33 is transmitted to the planetary gear 58 via the pinion gear 48. The planetary gear 58 revolves around the pinion gear 48 while rotating on its own axis in a state of meshing with the internal teeth of the internal gear 60. The planetary gear 58 is rotatably supported by the spindle 11 via a pin. Due to the revolution of the planetary gear 58, the spindle 11 rotates at a rotational speed lower than the rotational speed of the rotor shaft 33.

[0164] Each of Fig. 14 and Fig. 15 shows a cross-sectional view of the electric working machine 1 in a low-load state in which the tool holding shaft 15 is rotating with a low load.

[0165] 14, in a low load state, the spindle protrusion 69 comes into contact with the movable anvil 17, and the movable anvil 17 comes into contact with the hammer protrusion 84. In addition, the spindle protrusion 69 comes into contact with the movable anvil 17, and the movable anvil 17 comes into contact with the hammer protrusion 84.

[0166] In a low load state, the movable anvil 17 moves radially outward due to contact with the spindle protrusion 69. At least a portion of the movable anvil 17 is disposed radially outward from the outer circumferential surface of the anvil portion 98. Since at least a portion of the movable anvil 17 is disposed radially outward from the outer circumferential surface of the anvil portion 98, in a low load state, the hammer protrusion 84 comes into contact with at least a portion of the movable anvil 17.

[0167] Under low load conditions, the wedge effect of the movable anvil 17 prevents the movable anvil 17 from passing between the spindle protrusion 69 and the hammer protrusion 84, preventing relative rotation among the spindle 11, hammer 75, and tool holder shaft 15. The tool holder shaft 15 rotates together with the hammer 75 and spindle 11 via the movable anvil 17.

[0168] The cam ring 76 is connected to the hammer 75 via a guide groove 86 and a cam slide portion 87. The cam ring 76 is also pressed against the flange portion 11B of the spindle 11 by the elastic force of an elastic member 78. Therefore, in a low load state in which the hammer 75 and the spindle 11 do not rotate relative to each other, the cam ring 76 rotates together with the spindle 11 and the hammer 75. That is, in a low load state, the spindle 11, the hammer 75, the tool holder shaft 15, and the cam ring 76 rotate together.

[0169] 15, in a low load state, the cam ring 76 and the spindle 11 rotate together with the balls 77 disposed in the center of the spindle groove 71. In a low load state, the cam ring 76 is disposed at the rear end of the rear outer cylinder portion 81 of the hammer 75 in the axial direction.

[0170] Each of Fig. 16 and Fig. 17 shows a cross-sectional view of the electric operating machine 1 in a transition state immediately after the load applied to the tool holding shaft 15 has transitioned from a low load state to a high load state.

[0171] As the screw tightening operation progresses, the load on the tool holding shaft 15 increases, causing the rotational speed of the tool holding shaft 15 to decrease. Since the hammer 75 is connected to the tool holding shaft 15 via the movable anvil 17, the rotational speed of the hammer 75 also decreases as the rotational speed of the tool holding shaft 15 decreases. Furthermore, since the cam ring 76 is connected to the hammer 75 via the guide groove 86 and the cam slide portion 87, the rotational speed of the cam ring 76 also decreases as the rotational speed of the hammer 75 decreases. On the other hand, since the spindle 11 rotates due to the rotational force of the motor 6, the rotational speed of the spindle 11 does not decrease.

[0172] Although the rotation speed of the spindle 11 does not decrease, the rotation speeds of the tool holder shaft 15, the hammer 75, and the cam ring 76 decrease, so that the tool holder shaft 15, the hammer 75, and the cam ring 76 start to rotate relative to the spindle 11. The tool holder shaft 15, the hammer 75, and the cam ring 76 rotate together.

[0173] As shown in FIG. 16, when the load state transitions from a low load state to a high load state, the spindle protrusion 69 moves away from the movable anvil 17 due to the relative rotation of the tool holding shaft 15 and the hammer 75 with respect to the spindle 11 .

[0174] Because the cam ring 76 is connected to the hammer 75 via the guide groove 86 and the cam slide portion 87, the rotational speed of the cam ring 76 also decreases as the rotational speed of the hammer 75 decreases. Since the rotational speed of the spindle 11 does not decrease, if the spindle 11 continues to rotate with the rotational speed of the cam ring 76 decreasing, the balls 77 move inside the spindle groove 71 and the cam groove 88.

[0175] 17, when the load state transitions from a low load state to a high load state, balls 77 move from the center of spindle groove 71 toward the end. Cam ring 76 receives force from balls 77 and moves forward. Cam ring 76 moves forward while being guided by guide groove 86. Cam ring 76 moves forward against the elastic force of elastic member 78.

[0176] In this way, when the flange portion 11B of the spindle 11 and the cam ring 76 are rotating together in the forward direction, and the tool holding shaft 15 transitions from a low load state to a high load state, the rotational speed of the cam ring 76 decreases, and the flange portion 11B and the cam ring 76 begin to rotate relative to each other, the ball 77 moves from the center of the spindle groove 71 toward the other circumferential end, and the cam ring 76 receives a force from the ball 77 and moves forward.

[0177] Each of Fig. 18 and Fig. 19 shows a cross-sectional view of the electric operating machine 1 in a high-load state after a predetermined time has elapsed since transition from a low-load state to a high-load state.

[0178] Continuation of the high load state stops the rotation of the tool holder shaft 15, the hammer 75, and the cam ring 76. Even if the rotation of the tool holder shaft 15, the hammer 75, and the cam ring 76 stops, the spindle 11 continues to rotate by the rotational force of the motor 6.

[0179] When the tool holder shaft 15 is in a high load state, the rotation of the spindle 11 continues while the rotation of the tool holder shaft 15, the hammer 75, and the cam ring 76 is stopped. The cam ring 76 receives a force from the ball 77 and moves forward against the elastic force of the elastic member 78.

[0180] 18 , with the rotation of the tool holding shaft 15, the hammer 75, and the cam ring 76 stopped, the rotation of the spindle 11 continues, so that the spindle protrusion 69 moves further away from the movable anvil 17 in the rotational direction. As the spindle protrusion 69 moves away from the movable anvil 17, the movable anvil 17 becomes movable radially inward. As the movable anvil 17 moves radially inward beyond the outer circumferential surface 103 of the anvil portion 98, the hammer protrusion 84 moves away from the movable anvil 17. In other words, the lock of the hammer 75 by the movable anvil 17 is released, and the hammer 75 becomes rotatable relative to the spindle 11.

[0181] By releasing the lock of the hammer 75, the cam ring 76 also becomes rotatable relative to the spindle 11. The cam ring 76 moves backward relative to the hammer 75 due to the elastic force of the elastic member 78. The cam ring 76 moves backward while being guided by the guide groove 86. Since the cam ring 76 is rotatable relative to the spindle 11, as it moves backward, it receives force from the balls 77 and rotates in the forward direction. That is, the cam ring 76 rotates in the forward direction while moving backward. The balls 77 move from the end of the spindle groove 71 toward the center. Since the hammer 75 is connected to the cam ring 76 via the cam slide portion 87 and the guide groove 86, as the cam ring 76 rotates in the forward direction, the hammer 75 also rotates in the forward direction.

[0182] In this way, after the hammer 75 is unlocked, when the cam ring 76 receives an elastic force from the elastic member 78 so as to move rearward, the ball 77 moves from the other circumferential end of the spindle groove 71 toward the center of the spindle groove 71, and the cam ring 76 receives a force from the ball 77 and moves rearward while rotating relative to the flange portion 11B.

[0183] Each of FIGS. 20 and 21 shows a cross-sectional view of the electric working machine 1 in a hammer rotation state in which the hammer 75 is rotating to strike the movable anvil 17. FIG.

[0184] As shown in FIG. 20, in the rotating state of the hammer 75, the spindle 11 rotates in the normal direction by the rotational force of the motor 6. The hammer 75 rotates in the normal direction together with the cam ring 76 which rotates by the elastic force of the elastic member 78. The spindle 11 rotates such that the first spindle protrusion 691 separated from the first movable anvil 171 approaches the second movable anvil 172, and the second spindle protrusion 692 separated from the second movable anvil 172 approaches the first movable anvil 171. The hammer 75 also rotates such that the first hammer protrusion 841 separated from the first movable anvil 171 approaches the second movable anvil 172, and the second hammer protrusion 842 separated from the second movable anvil 172 approaches the first movable anvil 171.

[0185] The first hammer protrusion 841 revolves around the spindle 11 in the normal rotation direction so as to follow the first spindle protrusion 691. The first spindle protrusion 691 reaches the second movable anvil 172 before the first hammer protrusion 841. The second hammer protrusion 842 revolves around the spindle 11 in the normal rotation direction so as to follow the second spindle protrusion 692. The second spindle protrusion 692 reaches the first movable anvil 171 before the second hammer protrusion 842.

[0186] Each of Figures 22 and 23 shows a cross-sectional view of the electric working machine 1 in a striking state in which the hammer 75 strikes the movable anvil 17.

[0187] As described above, the first spindle projection 691 reaches the second movable anvil 172 before the first hammer projection 841. The first spindle projection 691 comes into contact with the second movable anvil 172. The second movable anvil 172 moves radially outward due to the contact with the first spindle projection 691. At least a portion of the second movable anvil 172 is disposed radially outward from the outer circumferential surface 103 of the anvil portion 98.

[0188] The first hammer protrusion 841 reaches the second movable anvil 172 after the first spindle protrusion 691 reaches the second movable anvil 172. That is, the first hammer protrusion 841 reaches the second movable anvil 172 after the second movable anvil 172 moves radially outward. The first hammer protrusion 841 strikes the second movable anvil 172, which is disposed radially outward from the outer circumferential surface 103 of the anvil part 98, in the rotational direction. When the second movable anvil 172 is struck by the first hammer protrusion 841, the position of the second movable anvil 172 in the radial direction is constrained by the first spindle protrusion 691, and the position of the second movable anvil 172 in the circumferential direction is constrained by the inner surface of the anvil hole 104. This allows the first hammer protrusion 841 to strike the second movable anvil 172.

[0189] The second spindle protrusion 692 reaches the first movable anvil 171 before the second hammer protrusion 842. The first movable anvil 171 moves radially outward due to contact with the second spindle protrusion 692. The second hammer protrusion 842 reaches the first movable anvil 171 after the first movable anvil 171 moves radially outward. The second hammer protrusion 842 strikes the first movable anvil 171, which is disposed radially outward from the outer circumferential surface 103 of the anvil part 98, in the rotational direction. When the first movable anvil 171 is struck by the second hammer protrusion 842, the position of the first movable anvil 171 in the radial direction is constrained by the second spindle protrusion 692, and the position of the first movable anvil 171 in the circumferential direction is constrained by the inner surface of the anvil hole 104. This allows the second hammer protrusion 842 to strike the first movable anvil 171.

[0190] The striking of the second movable anvil 172 by the first hammer protrusion 841 and the striking of the first movable anvil 171 by the second hammer protrusion 842 are carried out substantially simultaneously. The movable anvil 17 is struck by the hammer protrusion 84 in a state in which it is disposed in the anvil hole 104 of the tool holding shaft 15. The tool holding shaft 15 is struck in the rotational direction by the hammer 75 via the two movable anvils 17.

[0191] The tool holder shaft 15 is struck in the rotational direction by the hammer 75, and rotates about the rotation axis AX with high torque, so that the screw is tightened with high torque into the work object.

[0192] As shown in FIG. 23, the cam ring 76 moves rearward, so that the ball 77 is located in the center of the spindle groove 71 in the impact state.

[0193] After the impact state ends, the electric operating machine 1 transitions from the impact state to the low load state.

[0194] As described with reference to Figs. 14 to 23, in the embodiment, the movable anvil 17 is struck by the hammer protrusion 84 as the spindle 11 makes a half rotation. That is, in the embodiment, the hammer protrusion 84 strikes the movable anvil 17 twice during one rotation of the spindle 11. The hammer protrusion 84 may strike the movable anvil 17 once during one rotation of the spindle 11. When the hammer protrusion 84 strikes the movable anvil 17 once during one rotation of the spindle 11, the hammer protrusion 84 can strike the movable anvil 17 at a higher rotation speed and with a higher inertia force than when the movable anvil 17 is struck twice. That is, when the hammer protrusion 84 strikes the movable anvil 17 once during one rotation of the spindle 11, the hammer 75 can strike the movable anvil 17 with a higher striking energy than when the movable anvil 17 is struck twice. By adjusting one or both of the elastic energy (spring constant) of the elastic member 78 and the rotational speed of the spindle 11, it is possible to adjust the number of times that the hammer protrusion 84 strikes the movable anvil 17 during one rotation of the spindle 11. As a secondary effect, the ease of deformation of the elastic member 78 leads to an accelerated timing at which the hammer protrusion 84 starts striking the movable anvil 17, thereby suppressing the occurrence of the cam-out phenomenon in which the tip of the tool comes off the tool hole (cross hole) of the screw during screw tightening work.

[0195] In this embodiment, two movable anvils 17 and two hammer protrusions 84 are provided. Three movable anvils 17 and three hammer protrusions 84 may be provided. Four movable anvils 17 and four hammer protrusions 84 may be provided. Five or more movable anvils 17 and five or more hammer protrusions 84 may be provided.

[0196] 14 to 23 are examples in which the spindle 11, the cam ring 76, the hammer 75, and the tool holder shaft 15 rotate in the forward direction for a screw tightening operation. When performing a screw loosening operation, the worker operates the forward / reverse switching lever 41 to rotate the spindle 11, the cam ring 76, the hammer 75, and the tool holder shaft 15 in the reverse direction. In a screw loosening operation, when the flange portion 11B of the spindle 11 and the cam ring 76 are rotating together in the reverse direction, the tool holder shaft 15 is in a high load state, the rotation speed of the cam ring 76 decreases, and the flange portion 11B and the cam ring 76 start to rotate relative to each other. As a result, the ball 77 moves from the center of the spindle groove 71 toward one end on the circumferential side, and the cam ring 76 receives a force from the ball 77 and moves forward. In addition, after the hammer 75 is unlocked, when an elastic force is applied from the elastic member 78 so that the cam ring 76 moves rearward, the ball 77 moves from one circumferential end of the spindle groove 71 toward the center of the spindle groove 71, and the cam ring 76 receives a force from the ball 77 and moves rearward while rotating relative to the flange portion 11B.

[0197] [effect] As described above, in the embodiment, the electric working machine 1 includes the motor 6 having the stator 21 and the rotor 22 that is at least partially disposed inside the stator 21 and rotates about the rotation axis AX, the spindle 11 that is disposed forward of the stator 21 in the front-rear direction parallel to the rotation axis AX and rotates by the rotational force generated by the rotor 22, and the spindle bearing 12 that rotatably supports the rear part of the spindle 11. The spindle bearing 12 is disposed radially inside the stator 21.

[0198] In the above configuration, the spindle bearing 12 is disposed radially inside the stator 21, and the spindle bearing 12 overlaps with at least a portion of the stator 21 in the front-to-rear direction, thereby preventing the electric working machine 1 from becoming larger in size in the front-to-rear direction parallel to the rotation axis AX of the motor 6. The dimension of the electric working machine 1 in the front-to-rear direction parallel to the rotation axis AX of the motor 6 refers to the dimension in the front-to-rear direction between the rear end of the rear case 3 and the front end of the tool holding shaft 15. According to the technology disclosed in this specification, the dimension of the electric working machine 1 in the front-to-rear direction parallel to the rotation axis AX of the motor 6 is prevented from becoming larger.

[0199] In the embodiment, the stator 21 has a stator core 23 and an insulator 26 at least a portion of which is fixed to a front portion of the stator core 23. The spindle bearing 12 is disposed radially inside the insulator 26.

[0200] In the above configuration, the spindle bearing 12 is positioned radially inside the insulator 26 (front insulator 28), and the spindle bearing 12 overlaps with at least a portion of the insulator 26 in the fore-and-aft direction, thereby preventing the electric work machine 1 from becoming larger in size in the fore-and-aft direction parallel to the rotation shaft of the motor 6.

[0201] In the embodiment, the electric operating machine 1 includes a bearing box 5 that holds the spindle bearing 12. The insulator 26 is connected to the bearing box 5.

[0202] In the above configuration, the relative movement between the stator 21 and the bearing box 5 is suppressed.

[0203] In the embodiment, the bearing box 5 may have an insertion hole 5H into which the pin portion 28C provided in the insulator 26 is inserted.

[0204] In the above configuration, the insulator 26 and the bearing box 5 are connected together by inserting the pin portion 28C into the insertion hole 5H.

[0205] In the embodiment, the bearing box 5 has a protrusion 5E which is a first protrusion that contacts the front end surface of the stator core 23.

[0206] In the above configuration, the stator 21 is supported by the protruding portion 5E of the bearing box 5.

[0207] In the embodiment, the electric operating machine 1 includes a hammer case 4 that houses a spindle 11. The bearing box 5 is disposed so as to cover an opening at the rear end of the hammer case 4.

[0208] In the above configuration, the bearing box 5 and the hammer case 4 are connected.

[0209] In the embodiment, the electric operating machine 1 includes a rear case 3 that houses at least a part of the motor 6. The rear case 3 and the hammer case 4 are fixed together by screws 20.

[0210] In the above configuration, the relative movement between the rear case 3 and the hammer case 4 is suppressed.

[0211] [Other embodiments] In the above-described embodiment, the electric working machine 1 is an impact driver, which is a type of impact tool. The impact tool may be an impact wrench. The electric working machine 1 does not have to be an impact tool. The technology disclosed in this specification is widely applicable to electric working machines having a motor, a spindle, and a spindle bearing.

[0212] In the above-described embodiment, the power source for the electric operating machine 1 does not have to be the battery pack 19, and may be a commercial power source (AC power source). [Explanation of symbols]

[0213] 1...electrical work machine, 2...housing, 2A...accommodation section, 2B...grip section, 2C...battery holding section, 2L...left housing, 2R...right housing, 3...rear case, 3A...tubular section, 3B...disk section, 3C...bearing holding section, 3D...screw boss section, 3E...projection section, 3F...screw opening, 3G...screw opening, 4...hammer case, 4A...large tube section, 4B...small tube section, 4C...projection section, 4D...screw boss section, 4E...projection section, 4F...screw hole, 4G...screw opening, 5...bearing box, 5A...large tube section, 5B...small tube section, 5C...front annular section, 5D...rear annular section, 5E...projection section, 5F...rotation prevention section , 5G... boss portion, 5H... insertion hole, 5J... recess, 5K... recess, 6... motor, 7... fan, 7A... bush, 8... rear rotor bearing, 9... front rotor bearing, 10... reduction mechanism, 11... spindle, 11A... spindle shaft portion, 11B... flange portion, 11C... pin support portion, 11D... connection portion, 11E... convex portion, 12... spindle bearing, 13... impact mechanism, 14... hammer bearing, 15... tool holding shaft, 16... shaft bearing, 17... movable anvil, 18... tool holding mechanism, 19... battery pack, 20... screw, 21... stator, 22... rotor , 23... stator core, 24... inner core, 24A... inner yoke portion, 24B... teeth portion, 24C... connecting portion, 25... outer core, 25A... recess, 26... insulator, 27... rear insulator, 27A... rear plate portion, 27D... support plate portion, 28... front insulator, 28A... front plate portion, 28B... cylindrical portion, 28C... pin portion, 28D... support plate portion, 29... coil, 30... jumper, 31... fusing terminal, 32... rotor magnet, 33... rotor shaft, 33A... magnet fixing portion, 33B... fan fixing portion, 33C... rear support portion, 33 D...front support portion, 40...trigger lever, 41...forward / reverse switching lever, 48...pinion gear, 58...planetary gear, 59...pin, 60...internal gear, 62...projection portion, 69...spindle projection portion, 70...ball groove, 71...spindle groove, 74...washer, 75...hammer, 76...cam ring, 77...ball, 78...elastic member, 79...washer, 80...rotating ball, 81...rear outer cylinder portion, 82...front outer cylinder portion, 83...inner cylinder portion, 84...hammer projection portion, 85...ball groove, 86...guide groove, 87...cam slide portion, 88...cam groove, 89...recess, 90...support surface, 91...disc spring,93...screw, 94...screw hole, 95...front end surface, 96...opposing surface, 97...tool holding portion, 98...anvil portion, 99...tool hole, 100...recess, 101...inner peripheral surface, 103...outer peripheral surface, 104...anvil hole, 105...support recess, 106...support ball, 107...O-ring, 108...restraining member, 110...retaining ball, 111...leaf spring, 112...sleeve, 113...coil spring, 114...positioning member, 115...support recess, 171...first movable anvil, 172...second movable anvil, 691...first spindle protrusion, 692...second spindle protrusion, 841...first hammer protrusion, 842...second hammer protrusion, AX...rotating shaft.

Claims

1. A motor having a stator and a rotor at least a part of which is disposed inside the stator and rotates about a rotation axis, a spindle disposed forward of the stator in a front-rear direction parallel to the rotation axis and rotated by a rotational force generated by the rotor, and a spindle bearing that rotatably supports a rear portion of the spindle. The spindle bearing is disposed radially inside the stator. An electric power tool.

2. The stator has a stator core and an insulator at least a part of which is fixed to a front portion of the stator core. The spindle bearing is disposed radially inside the insulator. The electric power tool according to Claim 1.

3. A bearing box that holds the spindle bearing is provided. The insulator is connected to the bearing box. The electric power tool according to Claim 2.

4. The bearing box has an insertion hole into which a pin portion provided on the insulator is inserted. The electric power tool according to Claim 3.

5. The bearing box has a first convex portion that contacts a front end face of the stator core. The electric power tool according to Claim 3.

6. A hammer case that houses the spindle is provided. The bearing box is disposed so as to cover an opening at a rear end portion of the hammer case. The electric power tool according to Claim 3.

7. A rear case that houses at least a part of the motor is provided. The rear case and the hammer case are fixed by screws. The electric power tool according to Claim 6.

8. The hammer case has a second convex portion that contacts a front end face of the rear case. The electric power tool according to Claim 7.

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