Impact tool

Abstract

To inhibit the size increase of an impact tool.SOLUTION: An impact tool includes: a motor; a striking mechanism which is driven by the motor; an anvil having an anvil shaft part to which a tip tool is attached and an anvil projection part which protrudes from a rear end part of the anvil shaft part to a radial outer side and is struck in a rotation direction by the striking mechanism; a hammer case which houses the striking mechanism; a bearing which is held by the hammer case and is disposed around the anvil shaft part; a ring member which is arranged so that at least a part thereof faces a front surface of the anvil projection part and contacts with a rear end surface of the bearing; and an inhibition member which engages with the hammer case and the ring member to inhibit the ring member from being removed to the rear side.SELECTED DRAWING: Figure 5

Description

Technical Field

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

Background Art

[0002] In the technical field related to impact tools, impact tools as disclosed in Patent Document 1 are known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to improve the workability of using an impact tool, a technology for suppressing the enlargement of the impact tool is required.

[0005] The technology disclosed in this specification aims to suppress the enlargement of an impact tool.

Means for Solving the Problems

[0006] This specification discloses an impact tool. The impact tool may include a motor, a striking mechanism driven by the motor, an anvil shaft portion to which a tip tool is attached, an anvil protrusion that protrudes radially outward from the rear end portion of the anvil shaft portion and is struck in the rotational direction by the striking mechanism, an anvil having the anvil protrusion, a hammer case that houses the striking mechanism, a bearing held by the hammer case and disposed around the anvil shaft portion, a ring member disposed so as to face at least a part of the front surface of the anvil protrusion and in contact with the rear end surface of the bearing, and a restraining member that engages with the hammer case and the ring member and restrains the ring member from coming off backward.

Effects of the Invention

[0007] According to the technology disclosed in this specification, the increase in size of the impact tool is suppressed.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0009] In one or more embodiments, the impact tool may include a motor, a striking mechanism driven by the motor, an anvil shaft portion to which a tip tool is attached, an anvil protrusion that protrudes radially outward from the rear end portion of the anvil shaft portion and is struck in the rotational direction by the striking mechanism, an anvil having the anvil protrusion, a hammer case that houses the striking mechanism, a bearing held by the hammer case and disposed around the anvil shaft portion, a ring member disposed so as to face at least a part of the front surface of the anvil protrusion and in contact with the rear end surface of the bearing, and a restraining member that engages with the hammer case and the ring member and restrains the ring member from coming off backward.

[0010] In the above configuration, since the ring member contacts the rear end surface of the bearing, the bearing is supported by the ring member. The ring member is suppressed from coming off rearward by the suppressing member. Since the bearing is supported by the suppressing member via the ring member, the bearing is suppressed from coming off rearward. Since the bearing is supported by the ring member and the ring member is supported by the suppressing member, an increase in the size of the impact tool in the axial direction parallel to the rotation axis of the motor is suppressed.

[0011] In one or more embodiments, the hammer case may have a support surface facing at least a part of the front surface of the ring member, and at least a part of the ring member may be disposed between the front surface of the anvil protrusion and the support surface of the hammer case.

[0012] In the above configuration, the ring member is supported so as to be sandwiched in the front-rear direction by the support surface of the hammer case and the suppressing member. Thereby, the ring member is suppressed from moving with respect to the hammer case. The bearing is stably supported by the ring member.

[0013] In one or more embodiments, the ring member may suppress contact between the hammer case and the anvil protrusion.

[0014] In the above configuration, contact between the hammer case and the anvil protrusion is suppressed by the ring member disposed between the hammer case and the anvil protrusion.

[0015] In one or more embodiments, at least a part of the front surface of the ring member may contact the support surface of the hammer case.

[0016] In the above configuration, since the front surface of the ring member directly contacts the support surface of the hammer case, an increase in the size of the impact tool in the axial direction is suppressed.

[0017] In one or more embodiments, the outer edge of the front surface of the ring member may contact the support surface of the hammer case, and the inner edge of the front surface of the ring member may contact the rear end surface of the bearing.

[0018] In the above configuration, the support surface of the hammer case and the rear end surface of the bearing are arranged substantially in the same plane, and the front surface of the ring member contacts each of the support surface of the hammer case and the rear end surface of the bearing. Thereby, the bearing is stably supported by the ring member, and an increase in the size of the impact tool in the axial direction is suppressed.

[0019] In one or more embodiments, the outer edge of the rear surface of the ring member may contact the suppression member.

[0020] In the above configuration, since the rear surface of the ring member directly contacts the suppression member, an increase in the size of the impact tool in the axial direction is suppressed.

[0021] In one or more embodiments, a groove into which at least a part of the suppression member fits may be provided on the inner surface of the hammer case.

[0022] In the above configuration, fluctuations in the relative position between the hammer case and the suppression member in the axial direction are suppressed.

[0023] In one or more embodiments, in the front-rear direction, the suppression member may be disposed between the outer edge of the front surface of the anvil protrusion and the outer edge of the rear surface of the ring member.

[0024] In the above configuration, contact between the anvil protrusion and the ring member is suppressed by the suppression member disposed between the anvil protrusion and the ring member.

[0025] In one or more embodiments, the outer edge of the front surface of the anvil protrusion may be inclined rearward toward the outside in the radial direction.

[0026] In the above configuration, contact between the outer edge of the front surface of the anvil protrusion and the suppression member is suppressed.

[0027] In one or more embodiments, the hammer case may have a first cylindrical portion disposed around the striking mechanism and a second cylindrical portion disposed forward of the first cylindrical portion and having an outer diameter smaller than the outer diameter of the first cylindrical portion. The bearing may be held by the second cylindrical portion.

[0028] In the above configuration, the bearing is stably held by the second cylindrical portion.

[0029] [Embodiment] Embodiments will be described with reference to the drawings. In the embodiments, the positional relationships of the respective parts will be described using the terms left, right, front, rear, top, and bottom. These terms indicate relative positions or directions with respect to the center of the impact tool 1. The impact tool 1 has a motor 6 as a power source.

[0030] In the embodiments, the direction parallel to the rotation axis AX of the motor 6 is appropriately referred to as the axial direction, the direction around the rotation axis AX is appropriately referred to as the circumferential direction or the rotational direction, and the radial direction of the rotation axis AX is appropriately referred to as the radial direction.

[0031] The rotation axis AX extends in the front-rear direction. One side in the axial direction is the front, and the other side in the axial direction is the rear. Also, in the radial direction, a position close to the rotation axis AX or a direction approaching it is appropriately referred to as the inner radial side, and a position far from the rotation axis AX or a direction separating from it is appropriately referred to as the outer radial side.

[0032] <Impact Tool> FIG. 1 is a perspective view from the front showing the impact tool 1 according to the embodiment. FIG. 2 is a side view showing the upper part of the impact tool 1 according to the embodiment. FIG. 3 is a longitudinal sectional view showing the upper part of the impact tool 1 according to the embodiment. FIG. 4 is a cross-sectional view showing the upper part of the impact tool 1 according to the embodiment.

[0033] In an embodiment, the impact tool 1 is an impact driver which is a type of screwdriving tool. The impact tool 1 includes a housing 2, a rear cover 3, a hammer case 4, a hammer case cover 5, a motor 6, a speed reduction mechanism 7, a spindle 8, a striking mechanism 9, an anvil 10, a tool holding mechanism 11, a fan 12, a battery mounting portion 13, a trigger lever 14, a forward / reverse switching lever 15, an operation display portion 16, a mode switching switch 17, and a light assembly 18.

[0034] The housing 2 is made of synthetic resin. In the embodiment, the housing 2 is made of nylon. 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 by a plurality of screws 2S. The housing 2 is composed of a pair of split housings.

[0035] The housing 2 has a motor housing portion 21, a grip portion 22, and a battery holding portion 23.

[0036] The motor housing portion 21 is cylindrical. The motor housing portion 21 houses the motor 6. The motor housing portion 21 houses at least a part of the hammer case 4.

[0037] The grip portion 22 extends downward from the motor housing portion 21. The trigger lever 14 is provided at the upper part of the grip portion 22. The grip portion 22 is grasped by an operator.

[0038] The battery holding portion 23 is connected to the lower end portion of the grip portion 22. In each of the front-rear direction and the left-right direction, the outer dimensions of the battery holding portion 23 are larger than the outer dimensions of the grip portion 22.

[0039] The rear cover 3 is made of synthetic resin. The rear cover 3 is disposed behind the motor housing portion 21. The rear cover 3 houses at least a part of the fan 12. The fan 12 is disposed on the inner peripheral side of the rear cover 3. The rear cover 3 is disposed so as to cover the opening at the rear end portion of the motor housing portion 21. The rear cover 3 is fixed to the rear end portion of the motor housing portion 21 by two screws 3S.

[0040] The motor housing portion 21 has an air inlet 19. The rear cover 3 has an exhaust port 20. The air in the external space of the housing 2 flows into the internal space of the housing 2 through the air inlet 19. The air in the internal space of the housing 2 flows out to the external space of the housing 2 through the exhaust port 20.

[0041] The hammer case 4 is made of metal. In the embodiment, the hammer case 4 is made of aluminum. The hammer case 4 is cylindrical. The hammer case 4 is connected to the front portion of the motor housing portion 21. A bearing box 24 is fixed to the rear portion of the hammer case 4. A thread is formed on the outer peripheral portion of the bearing box 24. A thread groove is formed on the inner peripheral portion of the hammer case 4. The bearing box 24 and the hammer case 4 are fixed by coupling the thread of the bearing box 24 and the thread groove of the hammer case 4. The hammer case 4 is sandwiched between the left housing 2L and the right housing 2R. At least a part of the hammer case 4 is housed in the motor housing portion 21. The bearing box 24 is fixed to each of the motor housing portion 21 and the hammer case 4.

[0042] The hammer case 4 houses at least a part of the speed reduction mechanism 7, the spindle 8, the striking mechanism 9, and the anvil 10. At least a part of the speed reduction mechanism 7 is disposed inside the bearing box 24. The speed reduction mechanism 7 includes a plurality of gears.

[0043] The hammer case 4 has a first cylindrical portion 401 and a second cylindrical portion 402. The first cylindrical portion 401 is disposed around the striking mechanism 9. The second cylindrical portion 402 is disposed in front of the first cylindrical portion 401. The outer diameter of the second cylindrical portion 402 is smaller than the outer diameter of the first cylindrical portion 401.

[0044] The hammer case cover 5 covers at least a part of the surface of the hammer case 4. The hammer case cover 5 protects the hammer case 4. The hammer case cover 5 suppresses contact between the hammer case 4 and objects around the hammer case 4.

[0045] The motor 6 is a power source of the impact tool 1. The motor 6 is an inner rotor type brushless motor. The motor 6 has a stator 26 and a rotor 27. The stator 26 is supported by the motor housing portion 21. At least a part of the rotor 27 is disposed inside the stator 26. The rotor 27 rotates with respect to the stator 26. The rotor 27 rotates about a rotation axis AX extending in the front-rear direction.

[0046] The stator 26 has a stator core 28, a front insulator 29, a rear insulator 30, and a coil 31.

[0047] The stator core 28 is disposed radially outside the rotor 27. The stator core 28 includes a plurality of laminated steel plates. The steel plate is a metal plate mainly made of iron. The stator core 28 is cylindrical. The stator core 28 has a plurality of teeth that support the coil 31.

[0048] The front insulator 29 is provided at the front portion of the stator core 28. The rear insulator 30 is provided at the rear portion of the stator core 28. Each of the front insulator 29 and the rear insulator 30 is an electric insulating member made of synthetic resin. The front insulator 29 is disposed so as to cover a part of the surface of the teeth. The rear insulator 30 is disposed so as to cover a part of the surface of the teeth.

[0049] The coil 31 is mounted on the stator core 28 via the front insulator 29 and the rear insulator 30. A plurality of coils 31 are arranged. The coils 31 are arranged around the teeth of the stator core 28 via the front insulator 29 and the rear insulator 30. The coil 31 and the stator core 28 are electrically insulated by the front insulator 29 and the rear insulator 30. The plurality of coils 31 are connected via the husing terminal 38.

[0050] The rotor 27 rotates about the rotation axis AX. The rotor 27 includes a rotor core portion 32, a rotor shaft portion 33, a rotor magnet 34, and a sensor magnet 35.

[0051] Each of the rotor core portion 32 and the rotor shaft portion 33 is made of steel. The rotor shaft portion 33 protrudes in the front-rear direction from the end face of the rotor core portion 32. The rotor shaft portion 33 includes a front shaft portion 33F protruding forward from the front end face of the rotor core portion 32 and a rear shaft portion 33R protruding rearward from the rear end face of the rotor core portion 32.

[0052] The rotor magnet 34 is fixed to the rotor core portion 32. The rotor magnet 34 is cylindrical. The rotor magnet 34 is arranged around the rotor core portion 32.

[0053] The sensor magnet 35 is fixed to the rotor core portion 32. The sensor magnet 35 is annular. The sensor magnet 35 is arranged on the front end face of the rotor core portion 32 and the front end face of the rotor magnet 34.

[0054] The sensor substrate 37 is attached to the front insulator 29. The sensor substrate 37 is fixed to the front insulator 29 by screws 29S. The sensor substrate 37 includes a disc-shaped circuit board provided with a hole at the center and a rotation detection element supported by the circuit board. At least a part of the sensor substrate 37 faces the sensor magnet 35. The rotation detection element detects the position of the rotor 27 in the rotation direction by detecting the position of the sensor magnet 35 of the rotor 27.

[0055] The rotor shaft portion 33 is rotatably supported by a rotor bearing 39. The rotor bearing 39 includes a front rotor bearing 39F that rotatably supports the front shaft portion 33F and a rear rotor bearing 39R that rotatably supports the rear shaft portion 33R.

[0056] The front rotor bearing 39F is held by a bearing box 24. The bearing box 24 has a recess 24A that is recessed forward from the rear surface of the bearing box 24. The front rotor bearing 39F is disposed in the recess 24A. The rear rotor bearing 39R is held by a rear cover 3. The front end portion of the rotor shaft portion 33 is disposed in the internal space of the hammer case 4 through the opening of the bearing box 24.

[0057] A pinion gear 41 is formed at the front end portion of the rotor shaft portion 33. The pinion gear 41 is connected to at least a part of the speed reduction mechanism 7. The rotor shaft portion 33 is connected to the speed reduction mechanism 7 via the pinion gear 41.

[0058] The speed reduction mechanism 7 is disposed forward of the motor 6. The speed reduction mechanism 7 connects the rotor shaft portion 33 and the spindle 8. The speed reduction mechanism 7 transmits the rotation of the rotor 27 to the spindle 8. The speed reduction mechanism 7 rotates the spindle 8 at a rotational speed lower than the rotational speed of the rotor shaft portion 33. The speed reduction mechanism 7 includes a planetary gear mechanism.

[0059] The speed reduction mechanism 7 has a plurality of gears. The gears of the speed reduction mechanism 7 are driven by the rotor 27.

[0060] The speed reduction mechanism 7 has a plurality of planetary gears 42 arranged around the pinion gear 41 and an internal gear 43 arranged around the plurality of planetary gears 42. Each of the pinion gear 41, the planetary gears 42, and the internal gear 43 is housed in the hammer case 4. Each of the plurality of planetary gears 42 meshes with the pinion gear 41. The planetary gear 42 is rotatably supported by the spindle 8 via the pin 42P. The spindle 8 is rotated by the planetary gear 42. The internal gear 43 has internal teeth that mesh with the planetary gears 42. The internal gear 43 is fixed to the hammer case 4. The internal gear 43 is always non-rotatable relative to the hammer case 4.

[0061] When the rotor shaft portion 33 rotates due to the drive of the motor 6, the pinion gear 41 rotates, and the planetary gears 42 revolve around the pinion gear 41. The planetary gears 42 revolve while meshing with the internal teeth of the internal gear 43. Due to the revolution of the planetary gears 42, the spindle 8 connected to the planetary gears 42 via the pins 42P rotates at a rotational speed lower than the rotational speed of the rotor shaft portion 33.

[0062] The spindle 8 is arranged in front of at least a part of the motor 6. The spindle 8 is arranged in front of the stator 26. At least a part of the spindle 8 is arranged in front of the rotor 27. At least a part of the spindle 8 is arranged in front of the speed reduction mechanism 7. The spindle 8 is arranged behind the anvil 10. The spindle 8 is rotated by the rotor 27. The spindle 8 is rotated by the rotational force of the rotor 27 transmitted by the speed reduction mechanism 7. The spindle 8 transmits the rotational force of the motor 6 to the anvil 10 via the ball 48 and the hammer 47.

[0063] The spindle 8 has a flange portion 8A and a spindle shaft portion 8B that protrudes forward from the flange portion 8A. The planetary gear 42 is rotatably supported by the flange portion 8A via a pin 42P. The rotation axis of the spindle 8 coincides with the rotation axis AX of the motor 6. The spindle 8 rotates about the rotation axis AX. The spindle 8 is rotatably supported by a spindle bearing 44. A convex portion 8C is provided at the rear end portion of the spindle 8. The convex portion 8C protrudes rearward from the flange portion 8A. The convex portion 8C is arranged so as to surround the spindle bearing 44.

[0064] The bearing box 24 is arranged at at least a part around the spindle 8. The spindle bearing 44 is held by the bearing box 24. The bearing box 24 has a convex portion 24B that protrudes forward from the front surface of the bearing box 24. The spindle bearing 44 is arranged around the convex portion 24B.

[0065] The striking mechanism 9 is driven by the motor 6. The rotational force of the motor 6 is transmitted to the striking mechanism 9 via the speed reduction mechanism 7 and the spindle 8. The striking mechanism 9 strikes the anvil 10 in the rotational direction based on the rotational force of the spindle 8 that rotates by the motor 6. The striking mechanism 9 has a hammer 47, a ball 48, a first coil spring 49, a second coil spring 50, a third coil spring 51, a first washer 52, and a second washer 53. The striking mechanism 9 including the hammer 47, the ball 48, the first coil spring 49, the second coil spring 50, the third coil spring 51, the first washer 52, and the second washer 53 is housed in the first cylindrical portion 401 of the hammer case 4.

[0066] The hammer 47 is disposed forward of the speed reduction mechanism 7. The hammer 47 is disposed around the spindle 8. The hammer 47 is held by the spindle 8. The ball 48 is disposed between the spindle 8 and the hammer 47. The hammer 47 has a cylindrical hammer body 47D and a hammer projection 47E provided at the front portion of the hammer body 47D. A ring-shaped recess 47C is provided on the rear surface of the hammer body 47D. The recess 47C is recessed forward from the rear surface of the hammer body 47D.

[0067] The hammer 47 is disposed around the spindle shaft portion 8B. The hammer 47 has a hole 47A in which the spindle shaft portion 8B is disposed.

[0068] The hammer 47 is rotated by the motor 6. The rotational force of the motor 6 is transmitted to the hammer 47 via the speed reduction mechanism 7 and the spindle 8. The hammer 47 is rotatable together with the spindle 8 based on the rotational force of the spindle 8 rotated by the motor 6. The rotation axis of the hammer 47, the rotation axis of the spindle 8, and the rotation axis AX of the motor 6 coincide. The hammer 47 rotates about the rotation axis AX.

[0069] The first washer 52 is disposed inside the recess 47C. The first washer 52 is supported by the hammer 47 via a plurality of balls 54. The balls 54 are disposed forward of the first washer 52.

[0070] The second washer 53 is disposed rearward of the first washer 52 inside the recess 47C. The outer diameter of the second washer 53 is smaller than the outer diameter of the first washer 52. The second washer 53 and the hammer 47 are relatively movable in the front-rear direction.

[0071] The first coil spring 49 is disposed around the spindle shaft portion 8B. The rear end portion of the first coil spring 49 is supported by the flange portion 8A. The front end portion of the first coil spring 49 is disposed inside the recess 47C and supported by the first washer 52. The first coil spring 49 constantly generates an elastic force that moves the hammer 47 forward.

[0072] The second coil spring 50 is disposed around the spindle shaft portion 8B. The second coil spring 50 is disposed radially inside the first coil spring 49. The rear end portion of the second coil spring 50 is supported by the flange portion 8A. The front end portion of the second coil spring 50 is disposed inside the recess 47C and is supported by the second washer 53. The second coil spring 50 generates an elastic force that moves the hammer 47 forward when the hammer 47 moves rearward.

[0073] The third coil spring 51 is disposed around the spindle shaft portion 8B. The third coil spring 51 is disposed radially inside the first coil spring 49. The third coil spring 51 is disposed inside the recess 47C. The rear end portion of the third coil spring 51 is supported by the second washer 53. The front end portion of the third coil spring 51 is supported by the first washer 52. The third coil spring 51 generates an elastic force that moves the second coil spring 50 rearward. Due to the elastic force of the third coil spring 51, the rear end portion of the second coil spring 50 is pressed against the flange portion 8A. Thereby, the second coil spring 50 is suppressed from floating with respect to the flange portion 8A.

[0074] The ball 48 is made of a metal such as steel. The ball 48 is disposed between the spindle shaft portion 8B and the hammer 47. The spindle 8 has a spindle groove 8D in which at least a part of the ball 48 is disposed. The spindle groove 8D is provided in a part of the outer surface of the spindle shaft portion 8B. The hammer 47 has a hammer groove 47B in which at least a part of the ball 48 is disposed. The hammer groove 47B is provided in a part of the inner surface of the hammer 47. The ball 48 is disposed between the spindle groove 8D and the hammer groove 47B. The ball 48 can roll inside the spindle groove 8D and inside the hammer groove 47B respectively. The hammer 47 is movable along with the ball 48. The spindle 8 and the hammer 47 can move relative to each other in the axial direction and the rotational direction within the movable range defined by the spindle groove 8D and the hammer groove 47B.

[0075] Anvil 10 is disposed in front of motor 6. Anvil 10 is the output part of impact tool 1 that rotates based on the rotational force of rotor 27. At least a part of anvil 10 is disposed in front of hammer 47. Anvil 10 has a tool hole 10A into which a tip tool is inserted. Tool hole 10A is provided at the front end of anvil 10. The tip tool is attached to anvil 10.

[0076] Anvil 10 has an anvil convex portion 10B. Anvil convex portion 10B is provided at the rear end of anvil 10. Anvil convex portion 10B protrudes rearward from the rear end of anvil 10. Spindle 8 is disposed behind anvil 10. A spindle concave portion 8E is provided at the front end of spindle shaft portion 8B. Anvil convex portion 10B is disposed in spindle concave portion 8E.

[0077] Anvil 10 has a rod-shaped anvil shaft portion 101 and an anvil protrusion portion 102. Tool hole 10A is provided at the front end of anvil shaft portion 101. The tip tool is attached to anvil shaft portion 101. Anvil protrusion portion 102 is provided at the rear end of anvil 10. Anvil protrusion portion 102 protrudes radially outward from the rear end of anvil shaft portion 101.

[0078] Anvil 10 is rotatably supported by bearing 46. The rotation axis of anvil 10, the rotation axis of hammer 47, the rotation axis of spindle 8, and the rotation axis AX of motor 6 coincide. Anvil 10 rotates about rotation axis AX. Bearing 46 is disposed around anvil shaft portion 101. Bearing 46 is disposed inside the second cylindrical portion 402 of hammer case 4. Bearing 46 is held by the second cylindrical portion 402 of hammer case 4. Bearing 46 rotatably supports the front portion of anvil shaft portion 101. An O-ring 45 is disposed between bearing 46 and anvil shaft portion 101.

[0079] In the embodiment, two bearings 46 are arranged in the axial direction. In the following description, each of the two bearings 46 is appropriately referred to as bearing 46A and bearing 46B. Bearing 46A is arranged forward of bearing 46B.

[0080] Also, in the embodiment, two O-rings 45 are arranged in the axial direction. In the following description, each of the two O-rings 45 is appropriately referred to as O-ring 45A and O-ring 45B. O-ring 45A is arranged forward of O-ring 45B. O-ring 45A is arranged between bearing 46A and anvil shaft portion 101. O-ring 45B is arranged between bearing 46B and anvil shaft portion 101.

[0081] At least a part of the hammer 47 can contact the anvil protrusion 102. A hammer protrusion 47E that protrudes forward is provided at the front portion of the hammer 47. The hammer protrusion 47E and the anvil protrusion 102 can contact each other. With the hammer 47 and the anvil protrusion 102 in contact, when the motor 6 is driven, the anvil 10 rotates together with the hammer 47 and the spindle 8.

[0082] The anvil 10 is struck in the rotational direction by the hammer 47. For example, in a screwing operation, when the load acting on the anvil 10 increases, there may be a situation where the anvil 10 cannot be rotated only by the load of the first coil spring 49. When the anvil 10 cannot be rotated only by the load of the first coil spring 49, the rotation of the anvil 10 and the hammer 47 stops. The spindle 8 and the hammer 47 are relatively movable in the axial direction and the circumferential direction via the ball 48. Even when the rotation of the hammer 47 stops, the rotation of the spindle 8 continues by the power generated by the motor 6. When the spindle 8 rotates while the rotation of the hammer 47 has stopped, the ball 48 moves rearward while being guided by the spindle groove 8D and the hammer groove 47B, respectively. The hammer 47 receives a force from the ball 48 and moves rearward along with the ball 48. That is, the hammer 47 moves rearward when the spindle 8 rotates while the rotation of the anvil 10 has been stopped. When the hammer 47 moves rearward, the contact between the hammer 47 and the anvil protrusion 102 is released.

[0083] As described above, the first coil spring 49 constantly generates an elastic force that moves the hammer 47 forward. The second coil spring 50 generates an elastic force that moves the hammer 47 forward after the hammer 47 has moved rearward from the specified position. The hammer 47 that has moved rearward moves forward by the elastic forces of the first coil spring 49 and the second coil spring 50. When the hammer 47 moves forward, it receives a force in the rotational direction from the ball 48. That is, the hammer 47 moves forward while rotating. When the hammer 47 moves forward while rotating, the hammer 47 contacts the anvil protrusion 102 while rotating. As a result, the anvil protrusion 102 is struck in the rotational direction by the hammer protrusion 47E of the hammer 47. Both the power of the motor 6 and the inertial force of the hammer 47 act on the anvil 10. Therefore, the anvil 10 can rotate around the rotation axis AX with high torque.

[0084] The tool holding mechanism 11 is disposed around the front portion of the anvil 10. The tool holding mechanism 11 holds the tip tool inserted into the tool hole 10A of the anvil 10. The tool holding mechanism 11 is detachable from the tip tool.

[0085] The tool holding mechanism 11 includes a ball 71, a leaf spring 72, a sleeve 73, a coil spring 74, and a positioning member 75.

[0086] The anvil 10 has a support recess 76 for supporting the ball 71. The support recess 76 is formed on the outer surface of the anvil shaft portion 101. In the embodiment, two support recesses 76 are formed in the anvil shaft portion 101.

[0087] The ball 71 is movably supported by the anvil 10. The ball 71 is disposed in the support recess 76. One ball 71 is disposed in one support recess 76.

[0088] A through hole connecting the inner surface of the support recess 76 and the inner surface of the tool hole 10A is formed in the anvil shaft portion 101. The diameter of the ball 71 is smaller than the diameter of the through hole. With the ball 71 supported by the support recess 76, at least a part of the ball 71 is disposed inside the tool hole 10A. The ball 71 can fix the tip tool inserted into the tool hole 10A. The ball 71 is movable between an engagement position for fixing the tip tool and a release position for releasing the fixing of the tip tool.

[0089] The leaf spring 72 generates an elastic force for moving the ball 71 to the engagement position. The leaf spring 72 is disposed around the anvil shaft portion 101. The leaf spring 72 generates an elastic force for moving the ball 71 forward.

[0090] The sleeve 73 is a cylindrical member. The sleeve 73 is disposed around the anvil shaft portion 101. The sleeve 73 is axially movable around the anvil shaft portion 101. The sleeve 73 can prevent the ball 71 disposed at the engagement position from escaping from the engagement position. The sleeve 73 can change the ball 71 to a state where it can be moved from the engagement position to the release position by being axially moved.

[0091] The sleeve 73 is movable around the anvil shaft portion 101 between a blocking position that blocks the radial outward movement of the ball 71 and an allowing position that allows the radial outward movement of the ball 71.

[0092] When the sleeve 73 is disposed at the blocking position, the ball 71 disposed at the engagement position is suppressed from moving radially outward. That is, when the sleeve 73 is disposed at the blocking position, the ball 71 disposed at the engagement position is prevented from escaping from the engagement position. When the sleeve 73 is disposed at the blocking position, the state in which the tip tool is fixed by the ball 71 is maintained.

[0093] When the sleeve 73 is moved to the allowing position, the ball 71 disposed at the engagement position is allowed to move radially outward. The sleeve 73 changes the ball 71 to a state where it can be moved from the engagement position to the release position by being moved to the allowing position. That is, when the sleeve 73 is disposed at the allowing position, the ball 71 disposed at the engagement position is allowed to escape from the engagement position. When the sleeve 73 is disposed at the allowing position, the state in which the tip tool is fixed by the ball 71 can be released.

[0094] The coil spring 74 generates an elastic force so that the sleeve 73 moves to the blocking position. The coil spring 74 is disposed around the anvil shaft portion 101. The blocking position is defined rearward of the allowing position. The coil spring 74 generates an elastic force that moves the sleeve 73 rearward.

[0095] The positioning member 75 is a ring-shaped member fixed to the outer surface of the anvil shaft portion 101. The positioning member 75 is fixed at a position where it can face the rear end portion of the sleeve 73. The positioning member 75 positions the sleeve 73 at the blocking position. The sleeve 73, which is applied with an elastic force to move rearward from the coil spring 74, is positioned at the blocking position by contacting the positioning member 75.

[0096] The fan 12 is disposed rearward of the stator 26 of the motor 6. The fan 12 generates an air flow for cooling the motor 6. The fan 12 is fixed to at least a part of the rotor 27. The fan 12 is fixed to the rear portion of the rear shaft portion 33R via the bush 12A. The fan 12 is disposed between the rear rotor bearing 39R and the stator 26. The fan 12 rotates by the rotation of the rotor 27. When the rotor shaft portion 33 rotates, the fan 12 rotates together with the rotor shaft portion 33. When the fan 12 rotates, air in the external space of the housing 2 flows into the internal space of the housing 2 through the intake port 19. The air that has flowed into the internal space of the housing 2 cools the motor 6 by flowing through the internal space of the housing 2. The air that has flowed through the internal space of the housing 2 flows out to the external space of the housing 2 through the exhaust port 20 due to the rotation of the fan 12.

[0097] The battery mounting portion 13 is disposed below the battery holding portion 23. The battery mounting portion 13 is connected to the battery pack 25. The battery pack 25 is mounted on the battery mounting portion 13. The battery pack 25 is detachable from the battery mounting portion 13. The battery pack 25 is mounted on the battery mounting portion 13 by being inserted into the battery mounting portion 13 from the front of the battery holding portion 23. The battery pack 25 is removed from the battery mounting portion 13 by being pulled out forward from the battery mounting portion 13. The battery pack 25 includes a secondary battery. In an embodiment, the battery pack 25 includes a rechargeable lithium-ion battery. By being mounted on the battery mounting portion 13, the battery pack 25 can supply power to the impact tool 1. The motor 6 is driven based on the power supplied from the battery pack 25. The operation display portion 16 operates by the power supplied from the battery pack 25.

[0098] The trigger lever 14 is provided on the grip portion 22. The trigger lever 14 is operated by an operator to start the motor 6. When the trigger lever 14 is operated, the driving and stopping of the motor 6 are switched.

[0099] The forward / reverse switching lever 15 is provided on the upper part of the grip portion 22. The forward / reverse switching lever 15 is operated by an operator. When the forward / reverse switching lever 15 is operated, the rotation direction of the motor 6 is switched from one of the forward rotation direction and the reverse rotation direction to the other. When the rotation direction of the motor 6 is switched, the rotation direction of the spindle 8 is switched.

[0100] The operation display unit 16 is provided in the battery holding unit 23. The operation display unit 16 is provided on the upper surface of the battery holding unit 23 on the front side of the grip unit 22. The operation display unit 16 has a plurality of operation buttons 16A and an indicator display 16B. When the operation buttons 16A are operated by an operator, the operation mode of the motor 6 is switched. The indicator display 16B has a plurality of light emitting units. The indicator display 16B displays the operation mode of the motor 6 by changing the lighting pattern of the plurality of light emitting units.

[0101] The mode changeover switch 17 is provided on the upper part of the trigger lever 14. The mode changeover switch 17 is operated by an operator to change the operation mode of the motor 6.

[0102] The light assembly 18 emits illumination light. The light assembly 18 illuminates the anvil 10 and the periphery of the anvil 10 with the illumination light. The light assembly 18 illuminates the front of the anvil 10 with the illumination light. Further, the light assembly 18 illuminates the tip tool attached to the anvil 10 and the periphery of the tip tool with the illumination light. In the embodiment, the light assembly 18 includes a ring-shaped base member 18A and a plurality of light emitting elements 18B held by the base member 18A. The base member 18A is disposed around the second cylindrical portion 402 of the hammer case 4. Further, the light assembly 18 has a ring member 18C that suppresses the base member 18A from coming out forward from the second cylindrical portion 402.

[0103] <Ring member and suppression member> FIG. 5 is an enlarged view of a part of FIG. 4. FIG. 6 is an exploded perspective view showing a part of the impact tool 1 according to the embodiment.

[0104] As shown in FIGS. 3, 4, 5, and 6, the impact tool 1 includes a hammer case 4, a bearing 46, an O-ring 45, a ring member 61, and a suppression member 62.

[0105] The hammer case 4 has a first cylindrical portion 401 and a second cylindrical portion 402. The first cylindrical portion 401 is disposed around the striking mechanism 9. The second cylindrical portion 402 is disposed forward of the first cylindrical portion 401. The outer diameter of the second cylindrical portion 402 is smaller than the outer diameter of the first cylindrical portion 401. The bearing 46 is held by the hammer case 4. The bearing 46 is disposed inside the second cylindrical portion 402 of the hammer case 4.

[0106] The bearing 46 is disposed around the anvil shaft portion 101. The O-ring 45 is disposed between the outer peripheral portion of the anvil shaft portion 101 and the inner peripheral portion of the bearing 46. The O-ring 45 contacts each of the outer peripheral portion of the anvil shaft portion 101 and the inner peripheral portion of the bearing 46. The bearing 46 rotatably supports the anvil shaft portion 101. As described above, two bearings 46 are disposed in the front-rear direction. Two O-rings 45 are disposed in the front-rear direction. The bearing 46 includes a bearing 46A and a bearing 46B disposed rearward of the bearing 46A. The O-ring 45 includes an O-ring 45A and an O-ring 45B disposed rearward of the O-ring 45A. The O-ring 45A is disposed between the bearing 46A and the anvil shaft portion 101. The O-ring 45B is disposed between the bearing 46B and the anvil shaft portion 101.

[0107] The bearing 46 is a ball bearing. Each of the bearing 46A and the bearing 46B has an inner ring 46C, a ball 46D, and an outer ring 46E. The inner ring 46C of the bearing 46A contacts the O-ring 45A. The inner ring 46C of the bearing 46B contacts the O-ring 45B. The ball 46D is disposed between the inner ring 46C and the outer ring 46E in the radial direction. The ball 46D contacts each of the inner ring 46C and the outer ring 46E. A plurality of balls 46D are disposed in the circumferential direction. The outer ring 46E is disposed radially outside the inner ring 46C and the ball 46D. The outer ring 46E of the bearing 46A contacts the inner peripheral surface of the second cylindrical portion 402. The outer ring 46E of the bearing 46B contacts the inner peripheral surface of the second cylindrical portion 402.

[0108] The ring member 61 is an annular member. The ring member 61 is made of metal. Iron is exemplified as the metal forming the ring member 61. Each of the front and rear surfaces of the ring member 61 is flat.

[0109] In the front-rear direction, the ring member 61 is disposed between the anvil projection 102 and the rear bearing 46B. The bearing 46B is disposed forward of the ring member 61. The anvil projection 102 is disposed rearward of the ring member 61. At least a part of the rear surface of the ring member 61 is disposed to face the front surface of the anvil projection 102. At least a part of the front surface of the ring member 61 contacts the rear end surface of the rear bearing 46B.

[0110] The restraining member 62 engages with each of the hammer case 4 and the ring member 61. The restraining member 62 prevents the ring member 61 from coming off rearward. A snap ring or a C-ring is exemplified as the restraining member 62. The restraining member 62 is disposed to contact the ring member 61.

[0111] The hammer case 4 has a support surface 4A facing at least a part of the front surface of the ring member 61 and an inner circumferential surface 4C facing the outer circumferential surface of the ring member 61. The support surface 4A of the hammer case 4 and the rear end surface of the rear bearing 46 are disposed substantially in the same plane. At least a part of the ring member 61 is disposed between the front surface of the anvil projection 102 and the support surface 4A of the hammer case 4.

[0112] The ring member 61 suppresses contact between the hammer case 4 and the anvil projection 102.

[0113] At least a part of the front surface of the ring member 61 contacts the support surface 4A of the hammer case 4. Also, at least a part of the front surface of the ring member 61 contacts the rear end surface of the rear bearing 46B.

[0114] As shown in FIG. 5, a front outer edge portion 61A showing the outer edge portion of the front surface of the ring member 61 contacts the support surface 4A of the hammer case 4. The outer peripheral surface of the ring member 61 can contact the inner peripheral surface 4C of the hammer case 4. A front inner edge portion 61B showing the inner edge portion of the front surface of the ring member 61 can contact the rear end surface of the outer ring 46E of the bearing 46B. The ring member 61 is disposed radially outside the inner ring 46C of the bearing 46B. The ring member 61 and the inner ring 46C of the bearing 46B do not contact each other.

[0115] A rear outer edge portion 61C showing the outer edge portion of the rear surface of the ring member 61 contacts the suppression member 62.

[0116] A groove 4B into which at least a part of the suppression member 62 fits is provided on the inner surface of the first cylindrical portion 401 of the hammer case 4. The hammer case 4 has a first support surface 4D connected to the rear end portion of the inner peripheral surface 4C, a second support surface 4E disposed behind the first support surface 4D, and an inner peripheral surface 4F. The first support surface 4D faces rearward. The first support surface 4D is disposed radially outside the inner peripheral surface 4C. The second support surface 4E faces forward. The second support surface 4E faces the first support surface 4D. The inner peripheral surface 4F is disposed so as to connect the radially outer end portion of the first support surface 4D and the radially outer end portion of the second support surface 4E. The first support surface 4D can face the outer edge portion of the front surface of the suppression member 62. The second support surface 4E can face the outer edge portion of the rear surface of the suppression member 62. The inner peripheral surface 4F can face the outer peripheral surface of the suppression member 62. The groove 4B is defined by the first support surface 4D, the second support surface 4E, and the inner peripheral surface 4F. By disposing the suppression member 62 in the groove 4B, at least the fluctuation of the relative position between the hammer case 4 and the suppression member 62 in the axial direction is suppressed.

[0117] The ring member 61 and the suppression member 62 prevent the bearing 46 from falling off rearward (the other axial side).

[0118] As shown in FIG. 3, a front outer edge portion 102A showing the outer edge portion of the front surface of the anvil protrusion 102 inclines rearward toward the radially outer side.

[0119] In the front-rear direction, the suppression member 62 is disposed between the front outer edge portion 102A of the anvil projection 102 and the rear outer edge portion 61C of the ring member 61.

[0120] <Operation of the impact tool> Next, the operation of the impact tool 1 will be described. For example, when performing a screwing operation on a work target, a tip tool (driver bit) used for the screwing operation is inserted into the tool hole 10A of the anvil 10. The tip tool inserted into the tool hole 10A is held by the tool holding mechanism 11. After the tip tool is attached to the anvil 10, the operator holds the grip portion 22 with, for example, the right hand and operates the trigger lever 14 by pulling it with the index finger of the right hand. When the trigger lever 14 is operated, power is supplied from the battery pack 25 to the motor 6, the motor 6 is started, and at the same time, the light assembly 18 is lit. When the motor 6 is started, the rotor shaft portion 33 of the rotor 27 rotates. When the rotor shaft portion 33 rotates, the rotational force of the rotor shaft portion 33 is transmitted to the planetary gear 42 via the pinion gear 41. The planetary gear 42 revolves around the pinion gear 41 while rotating in a state of meshing with the internal teeth of the internal gear 43. The planetary gear 42 is rotatably supported by the spindle 8 via the pin 42P. Due to the revolution of the planetary gear 42, the spindle 8 rotates at a rotational speed lower than the rotational speed of the rotor shaft portion 33.

[0121] When the spindle 8 rotates while the hammer 47 and the anvil projection 102 are in contact with each other, the anvil 10 rotates together with the hammer 47 and the spindle 8. As the anvil 10 rotates, the screwing operation progresses.

[0122] When a load equal to or greater than a predetermined value acts on the anvil 10 due to the progress of the screwing operation, the rotation of the anvil 10 and the hammer 47 stops. When the spindle 8 rotates while the rotation of the hammer 47 has stopped, the hammer 47 moves rearward. When the hammer 47 moves rearward, the contact between the hammer 47 and the anvil projection 102 is released. The hammer 47 that has moved rearward moves forward while rotating by the elastic force of the first coil spring 49 and the second coil spring 50. When the hammer 47 moves forward while rotating, the anvil 10 is struck in the rotational direction by the hammer 47. As a result, the anvil 10 rotates about the rotation axis AX with high torque. Therefore, the screw is tightened onto the work piece with high torque.

[0123] <Effect> As described above, in the embodiment, the impact tool 1 includes a motor 6, a striking mechanism 9 driven by the motor 6, an anvil shaft portion 101 to which a tip tool is attached, an anvil projection 102 that projects radially outward from the rear end portion of the anvil shaft portion 101 and is struck in the rotational direction by the striking mechanism 9, an anvil 10 having the above, a hammer case 4 that houses the striking mechanism 9, a bearing 46 held by the hammer case 4 and disposed around the anvil shaft portion 101, a ring member 61 disposed so as to face at least a part of the front surface of the anvil projection 102 and in contact with the rear end surface of the bearing 46, and a restraining member 62 that engages with the hammer case 4 and the ring member 61 and restrains the ring member 61 from coming off rearward.

[0124] In the above configuration, since the ring member 61 contacts the rear end surface of the bearing 46, the bearing 46 is supported by the ring member 61. The ring member 61 is suppressed from coming off rearward by the suppressing member 62. Since the bearing 46 is supported by the suppressing member 62 via the ring member 61, the bearing 46 is suppressed from coming off rearward. Since the bearing 46 is supported by the ring member 61 and the ring member 61 is supported by the suppressing member 62, the increase in size of the impact tool 1 is suppressed. In particular, an increase in the dimension of the upper portion of the impact tool 1 in the axial direction parallel to the rotation axis AX of the motor 6 is suppressed. For example, an increase in the axial length indicating the distance between the rear end surface of the rear cover 3 and the front end surface of the anvil shaft portion 101 is suppressed.

[0125] In the embodiment, the hammer case 4 has a support surface 4A facing at least a part of the front surface of the ring member 61, and at least a part of the ring member 61 is disposed between the front surface of the anvil protrusion 102 and the support surface 4A of the hammer case 4.

[0126] In the above configuration, the ring member 61 is supported so as to be sandwiched in the front-rear direction by the support surface 4A of the hammer case 4 and the suppressing member 62. Thereby, the ring member 61 is suppressed from moving with respect to the hammer case 4. The bearing 46 is stably supported by the ring member 61.

[0127] In the embodiment, the ring member 61 suppresses contact between the hammer case 4 and the anvil protrusion 102.

[0128] In the above configuration, contact between the hammer case 4 and the anvil protrusion 102 is suppressed by the ring member 61 disposed between the hammer case 4 and the anvil protrusion 102.

[0129] In the embodiment, at least a part of the front surface of the ring member 61 contacts the support surface 4A of the hammer case 4.

[0130] In the above configuration, since the front surface of the ring member 61 directly contacts the support surface 4A of the hammer case 4, the increase in the size of the impact tool 1 in the axial direction is suppressed. That is, the increase in the axial length is suppressed.

[0131] In the embodiment, a front outer edge portion 61A indicating the outer edge portion of the front surface of the ring member 61 contacts the support surface 4A of the hammer case 4, and a front inner edge portion 61B indicating the inner edge portion of the front surface of the ring member 61 contacts the rear end surface of the bearing 46.

[0132] In the above configuration, the support surface 4A of the hammer case 4 and the rear end surface of the bearing 46 are arranged substantially in the same plane, and the front surface of the ring member 61 contacts each of the support surface 4A of the hammer case 4 and the rear end surface of the bearing 46. Thereby, the bearing 46 is stably supported by the ring member 61, and the increase in the size of the impact tool 1 in the axial direction is suppressed. That is, the increase in the axial length is suppressed.

[0133] In the embodiment, a rear outer edge portion 61C indicating the outer edge portion of the rear surface of the ring member 61 contacts the suppressing member 62.

[0134] In the above configuration, since the rear surface of the ring member 61 directly contacts the suppressing member 62, the increase in the size of the impact tool 1 in the axial direction is suppressed. That is, the increase in the axial length is suppressed.

[0135] In the embodiment, a groove 4B into which at least a part of the suppressing member 62 is fitted is provided on the inner surface of the hammer case 4.

[0136] In the above configuration, the fluctuation of the relative position between the hammer case 4 and the suppressing member 62 in the axial direction is suppressed.

[0137] In the embodiment, in the front-rear direction, the suppressing member 62 is arranged between a front outer edge portion 102A indicating the outer edge portion of the front surface of the anvil protrusion 102 and the rear outer edge portion 61C of the ring member 61.

[0138] In the above configuration, the contact between the anvil protrusion 102 and the ring member 61 is suppressed by the suppression member 62 disposed between the anvil protrusion 102 and the ring member 61.

[0139] In the embodiment, the front outer edge portion 102A of the anvil protrusion 102 inclines rearward toward the radially outer side.

[0140] In the above configuration, the contact between the front outer edge portion 102A of the anvil protrusion 102 and the suppression member 62 is suppressed.

[0141] In the embodiment, the hammer case 4 has a first cylindrical portion 401 disposed around the striking mechanism 9 and a second cylindrical portion 402 disposed forward of the first cylindrical portion 401 and having an outer diameter smaller than the outer diameter of the first cylindrical portion 401. The bearing 46 is held by the second cylindrical portion 402.

[0142] In the above configuration, the bearing 46 is stably held by the second cylindrical portion 402.

[0143] <Modification> In the above-described embodiment, the impact tool 1 is an impact driver. The impact tool 1 may be an impact wrench.

[0144] In the above-described embodiment, the power source of the impact tool 1 does not have to be the battery pack 25 and may be a commercial power source (alternating current power source).

Description of Reference Numerals

[0145] 1... Impact tool, 2... Housing, 2L... Left housing, 2R... Right housing, 2S... Screw, 3... Rear cover, 3S... Screw, 4... Hammer case, 4A... Support surface, 4B... Groove, 4C... Inner peripheral surface, 4D... First support surface, 4E... Second support surface, 4F... Inner peripheral surface, 5... Hammer case cover, 6... Motor, 7... Reduction mechanism, 8... Spindle, 8A... Flange portion, 8B... Spindle shaft portion, 8C... Protrusion, 8D... Spindle groove, 8E... Spindle recess, 9... Striking mechanism, 10... Anvil, 10A... Tool hole, 10B... Anvil protrusion, 11... Tool holding mechanism, 12... Fan, 12A... Bush, 13... Battery mounting portion, 14... Trigger lever, 15... Forward / reverse switching lever, 16... Operation display portion, 16A... Operation button, 16B... Indicator display, 17... Mode changeover switch, 18... Light assembly, 18A... Base member, 18B... Light emitting element, 18C... Ring member, 19... Air intake port, 20... Exhaust port, 21... Motor housing portion, 22... Grip portion, 23... Battery holding portion, 24... Bearing box, 24A... Recess, 24B... Protrusion, 25... Battery pack, 26... Stator, 27... Rotor, 28... Stator core, 29... Front insulator, 29S... Screw, 30... Rear insulator, 31... Coil, 32... Rotor core portion, 33... Rotor shaft portion, 33F... Front shaft portion, 33R... Rear shaft portion, 34... Rotor magnet, 35... Sensor magnet, 37... Sensor substrate, 38... Hugging terminal, 39... Rotor bearing, 39F... Front rotor bearing, 39R... Rear rotor bearing, 41... Pinion gear, 42... Planetary gear, 42P... Pin, 43... Internal gear, 44... Spindle bearing, 45... O-ring, 45A... O-ring, 45B... O-ring, 46... Bearing, 46A... Bearing, 46B... Bearing, 46C... Inner ring, 46D... Ball, 46E... Outer ring, 47... Hammer, 47A... Hole, 47B... Hammer groove, 47C... Recess, 47D... Hammer body, 47E... Hammer protrusion, 48... Ball, 49... First coil spring, 50... Second coil spring, 51... Third coil spring, 52... First washer, 53... Second washer, 54... Ball, 61... Ring member, 61A... Front outer edge portion, 61B... Front inner edge portion, 61C... Rear outer edge portion, 62... Suppressing member, 71... Ball, 72... Leaf spring, 73... Sleeve, 74... Coil spring, 75... Positioning member76…Support recess, 101…Anvil shaft portion, 102…Anvil protrusion, 102A…Front outer edge portion, 401…First cylindrical portion, 402…Second cylindrical portion, AX…Rotation axis.

Claims

1. A motor, A striking mechanism driven by the motor, An anvil shaft portion to which a tip tool is attached, and an anvil protrusion that protrudes radially outward from the rear end portion of the anvil shaft portion and is struck in the rotational direction by the striking mechanism, an anvil having the same, A hammer case that houses the striking mechanism, A bearing held by the hammer case and disposed around the anvil shaft portion, A ring member disposed so as to face at least a part of the front surface of the anvil protrusion and in contact with the rear end surface of the bearing, A restraining member that engages with the hammer case and the ring member to prevent the ring member from coming off backward, A groove into which at least a part of the restraining member fits is provided on the inner surface of the hammer case, In the radial direction, a first cylindrical portion of the hammer case adjacent to the front of the groove is disposed outside a second cylindrical portion of the hammer case that holds the bearing, In the radial direction, the outer peripheral surface of the ring member is disposed outside the outer peripheral surface of the second cylindrical portion, An impact tool.

2. The hammer case has a support surface that faces at least a part of the front surface of the ring member, At least a part of the ring member is disposed between the front surface of the anvil protrusion and the support surface of the hammer case, The impact tool according to claim 1.

3. The ring member suppresses contact between the hammer case and the anvil protrusion, The impact tool according to claim 2.

4. At least a part of the front surface of the ring member is in contact with the support surface of the hammer case, The impact tool according to claim 2 or claim 3.

5. The outer edge portion of the front surface of the ring member is in contact with the support surface of the hammer case, The inner edge portion of the front surface of the ring member is in contact with the rear end surface of the bearing, The impact tool according to any one of claims 2 to 4.

6. The outer edge portion of the rear surface of the ring member is in contact with the restraining member, The impact tool according to any one of claims 1 to 5.

7. In the front-rear direction, the restraining member is disposed between the outer edge portion of the front surface of the anvil protrusion and the outer edge portion of the rear surface of the ring member, The impact tool according to any one of claims 1 to 6.

8. The outer edge portion of the front surface of the anvil protrusion is inclined rearward toward the radially outer side, The impact tool according to claim 7.

9. The hammer case has a first cylindrical portion disposed around the striking mechanism and a second cylindrical portion disposed in front of the first cylindrical portion and having an outer diameter smaller than the outer diameter of the first cylindrical portion. The bearing is held by the second cylindrical portion. An impact tool according to any one of claims 1 to 8.

Images