Impact tool

Abstract

The present application provides an impact tool capable of suppressing the large-scale of the impact tool. The impact tool is provided with: a motor; a striking mechanism driven by the motor; an anvil having an anvil shaft portion to which a front-end tool is fitted, and an anvil protrusion portion protruding from a rear end portion of the anvil shaft portion toward the radial outside and struck in the rotation direction by the striking mechanism; a hammer housing for housing the striking mechanism; a bearing held to the hammer housing and arranged around the anvil shaft portion; a ring member arranged in such a manner that at least a portion thereof opposes a front surface of the anvil protrusion portion and contacts a rear end surface of the bearing; and a suppression member engaged with the hammer housing and the ring member and for suppressing the ring member from falling out toward the rear.

Description

Technical Field

[0001] The technology disclosed in this specification relates to an impact tool. Background Technology

[0002] Among the technical fields involved in impact tools, impact tools as disclosed in Patent Document 1 are known.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-033738 Summary of the Invention

[0006] To improve the operability of impact tools, a technology is needed to curb the enlargement of impact tools.

[0007] The purpose of the technology disclosed in this specification is to suppress the enlargement of impact tools.

[0008] This specification discloses an impact tool. The impact tool may include: a motor; a striking mechanism driven by the motor; an anvil having: an anvil shaft for mounting a front tool, and an anvil protrusion protruding radially outward from the rear end of the anvil shaft and struck in the direction of rotation by the striking mechanism; a hammer housing for housing the striking mechanism; a bearing held in the hammer housing and disposed around the anvil shaft; an annular member disposed at least partially opposite the front surface of the anvil protrusion and in contact with the rear end face of the bearing; and a restraining member engaged with the hammer housing and the annular member, and for preventing the annular member from falling off rearward.

[0009] Invention Effects

[0010] The technology disclosed in this specification can suppress the enlargement of impact tools. Attached Figure Description

[0011] Figure 1 This is a perspective view showing the impact tool involved in the implementation method as viewed from the front.

[0012] Figure 2 This is a side view showing the upper part of the impact tool involved in the embodiment.

[0013] Figure 3 This is a longitudinal cross-sectional view showing the upper part of the impact tool involved in the embodiment.

[0014] Figure 4 This is a cross-sectional view showing the upper part of the impact tool involved in the embodiment.

[0015] Figure 5 It is Figure 4 The image is an enlarged version of a portion of the image.

[0016] Figure 6 This is an exploded perspective view showing a portion of the impact tool involved in the embodiment.

[0017] Explanation of reference numerals in the attached figures

[0018] 1…Impact tool; 2…Housing; 2L…Left housing; 2R…Right housing; 2S…Screw; 3…Rear cover; 3S…Screw; 4…Hammer housing; 4A…Support surface; 4B…Groove; 4C…Inner circumferential surface; 4D…First support surface; 4E…Second support surface; 4F…Inner circumferential surface; 5…Hammer housing cover; 6…Motor; 7…Reduction mechanism; 8…Spindle; 8A…Flange; 8B…Spindle shaft; 8C…Protrusion; 8D…Spindle groove; 8E…Spindle recess; 9…Strike mechanism; 10…Anvil; 10A…Tool hole; 10B…Anvil protrusion; 11…Tool holding mechanism; 12…Fan; 12A…Bushing; 13…Battery assembly; 4… Trigger lever; 15… Forward / reverse switch lever; 16… Operation display section; 16A… Operation button; 16B… Indicator light display; 17… Mode switch; 18… Lamp assembly; 18A… Base component; 18B… Light-emitting element; 18C… Ring component; 19… Air inlet; 20… Exhaust port; 21… Motor housing; 22… Handle; 23… Battery holder; 24… Bearing housing; 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; 33… Rotor shaft; 33F…Front shaft; 33R…Rear shaft; 34…Rotor magnet; 35…Sensor magnet; 37…Sensor substrate; 38…Fuse terminal; 39…Rotor bearing; 39F…Front rotor bearing; 39R…Rear rotor bearing; 41…Pin; 42…Planetary gear; 42P…Pin; 43…Internal gear; 44…Main shaft 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 bearing; 49… First helical spring; 50… Second helical spring; 51… Third helical spring; 52… First washer; 53… Second washer; 54… Ball bearing; 61… Annular component; 61A… Outer edge of front surface; 61B… Inner edge of front surface; 61C… Outer edge of rear surface; 62… Suppressing component; 71… Ball bearing; 72… Leaf spring; 73… Sleeve; 74… Helical spring; 75… Positioning component; 76… Support recess; 101… Anvil shaft; 102… Anvil protrusion; 102A… Outer edge of front surface; 401… First cylinder; 402… Second cylinder; AX… Rotation shaft. Detailed Implementation

[0019] In one or more embodiments, the impact tool comprises: a motor; a striking mechanism driven by the motor; an anvil having: an anvil shaft for mounting a front tool, and an anvil protrusion protruding radially outward from the rear end of the anvil shaft and struck in the direction of rotation by the striking mechanism; a hammer housing for housing the striking mechanism; a bearing held in the hammer housing and disposed around the anvil shaft; an annular member disposed at least partially opposite the front surface of the anvil protrusion and in contact with the rear end face of the bearing; and a restraining member engaged with the hammer housing and the annular member and for preventing the annular member from falling off rearward.

[0020] In the above configuration, the annular component contacts the rear end face of the bearing, so the bearing is supported by the annular component. The annular component can be prevented from falling rearward by the suppressing component. Since the bearing is supported by the suppressing component via the annular component, the possibility of the bearing falling rearward can be prevented. Because the bearing is supported by the annular component, and the annular component is supported by the suppressing component, the enlargement of the impact tool in the axial direction parallel to the rotating shaft of the motor can be prevented.

[0021] In one or more embodiments, the hammer housing may be configured such that: a support surface is opposite to at least a portion of the front surface of the annular member, and at least a portion of the annular member is disposed at a position between the front surface of the anvil protrusion and the support surface of the hammer housing.

[0022] In the above configuration, the annular component is supported by being clamped in the front-to-back direction by the support surface of the hammer housing and the suppressing component. This suppresses any movement of the annular component relative to the hammer housing. The bearing is stably supported on the annular component.

[0023] In one or more embodiments, the annular component can be used to suppress contact between the hammer housing and the anvil protrusion.

[0024] In the above configuration, the contact between the hammer housing and the anvil protrusion can be suppressed by the annular member disposed between the hammer housing and the anvil protrusion.

[0025] In one or more embodiments, at least a portion of the front surface of the annular component may contact the support surface of the hammer housing.

[0026] In the above configuration, the front surface of the annular component is in direct contact with the support surface of the hammer housing, thus suppressing the axial enlargement of the impact tool.

[0027] In one or more embodiments, the ring component may be configured such that the outer edge of the front surface of the ring component contacts the support surface of the hammer housing, and the inner edge of the front surface of the ring component contacts the rear end face of the bearing.

[0028] In the above configuration, the support surface of the hammer housing and the rear end face of the bearing are substantially disposed on the same plane, and the front surface of the annular component contacts both the support surface of the hammer housing and the rear end face of the bearing. Therefore, the bearing can be stably supported by the annular component, thereby preventing the impact tool from becoming too large in the axial direction.

[0029] In one or more embodiments, the outer edge of the rear surface of the annular component may come into contact with the suppressing component.

[0030] In the above configuration, the rear surface of the annular component is in direct contact with the suppressing component, thus suppressing the axial enlargement of the impact tool.

[0031] In one or more embodiments, a groove for at least a portion of the suppressing component may be provided on the inner surface of the hammer housing.

[0032] In the above configuration, it is possible to suppress: the change in the relative position of the hammer housing and the suppressing component in the axial direction.

[0033] In one or more embodiments, in the front-rear direction, the suppressing member may be positioned between the outer edge of the front surface of the anvil protrusion and the outer edge of the rear surface of the annular member.

[0034] In the above configuration, the contact between the anvil protrusion and the annular member can be suppressed by the suppressing member positioned between the anvil protrusion and the annular member.

[0035] In one or more embodiments, the outer edge of the front surface of the anvil protrusion may tend to be radially outward and tilted rearward.

[0036] In the above configuration, it is possible to suppress contact between the outer edge of the front surface of the anvil protrusion and the suppression member.

[0037] In one or more embodiments, the hammer housing may have: a first cylindrical portion disposed around the striking mechanism, and a second cylindrical portion disposed further forward than the first cylindrical portion and having an outer diameter smaller than that of the first cylindrical portion.

[0038] In the above configuration, the bearing can be stably held in the second cylindrical section.

[0039] [Implementation Method]

[0040] The embodiments will be described with reference to the accompanying drawings. In the embodiments, terms such as left, right, front, back, up, and down are used to describe the positional relationships of the various parts. These terms indicate the relative position or direction with respect to the center of the impact tool 1. The impact tool 1 has a motor 6 as a power source.

[0041] In the implementation, the direction parallel to the rotation axis AX of the motor 6 is appropriately referred to as: axial direction, the direction around the rotation axis AX is appropriately referred to as: circumferential or rotational direction, and the radial direction of the rotation axis AX is appropriately referred to as: radial direction.

[0042] The axis of rotation AX extends in the front-to-back direction. One side of the axis is the front, and the other side is the rear. Furthermore, regarding the radial direction, the position closer to or in the direction of the axis of rotation AX is appropriately called the "radial inner side," and the position farther from or in the direction of the axis of rotation AX is appropriately called the "radial outer side."

[0043] Impact Tools

[0044] Figure 1 This is a perspective view showing the impact tool 1 involved in the embodiment as viewed from the front. Figure 2 This is a side view showing the upper part of the impact tool 1 according to the embodiment. Figure 3 This is a longitudinal cross-sectional view showing the upper part of the impact tool 1 according to the embodiment. Figure 4 This is a transverse cross-sectional view showing the upper part of the impact tool 1 according to the embodiment.

[0045] In this embodiment, the impact tool 1 is an impact screwdriver, which is a type of screw fastening tool. The impact tool 1 includes: a housing 2, a rear cover 3, a hammer housing 4, a hammer housing cover 5, a motor 6, a reduction mechanism 7, a spindle 8, a striking mechanism 9, an anvil 10, a tool holding mechanism 11, a fan 12, a battery assembly 13, a trigger lever 14, a forward / reverse switching lever 15, an operation display 16, a mode switching switch 17, and a lamp assembly 18.

[0046] The outer casing 2 is made of synthetic resin. In one embodiment, the outer casing 2 is made of nylon. The outer casing 2 includes a left outer casing 2L and a right outer casing 2R disposed to the right of the left outer casing 2L. The left outer casing 2L and the right outer casing 2R are secured by a plurality of screws 2S. The outer casing 2 is composed of a pair of half-shell casings.

[0047] The housing 2 includes a motor housing 21, a gripping part 22, and a battery holding part 23.

[0048] The motor housing 21 is cylindrical. The motor housing 21 is used to house the motor 6. The motor housing 21 is used to house at least a portion of the hammer housing 4.

[0049] The grip 22 extends downward from the motor housing 21. The trigger lever 14 is located on the upper part of the grip 22. The grip 22 is held by the operator.

[0050] The battery holding part 23 is connected to the lower end of the gripping part 22. The external dimensions of the battery holding part 23 are larger than those of the gripping part 22 in all directions, including the front-back direction and the left-right direction.

[0051] The rear cover 3 is made of synthetic resin. The rear cover 3 is positioned behind the motor housing 21. The rear cover 3 is used to house at least a portion of the fan 12. The fan 12 is positioned on the inner circumferential side of the rear cover 3. The rear cover 3 is configured to cover the opening at the rear end of the motor housing 21. The rear cover 3 is fixed to the rear end of the motor housing 21 by two screws 3S.

[0052] The motor housing 21 has an air inlet 19. The rear cover 3 has an exhaust port 20. Air from the external space of the housing 2 flows into the internal space of the housing 2 through the air inlet 19. Air from the internal space of the housing 2 flows out to the external space of the housing 2 through the exhaust port 20.

[0053] The hammer housing 4 is made of metal. In this embodiment, the hammer housing 4 is made of aluminum. The hammer housing 4 is cylindrical. The hammer housing 4 is connected to the front of the motor housing 21. A bearing housing 24 is fixed to the rear of the hammer housing 4. Threaded teeth are formed on the outer periphery of the bearing housing 24. Threaded grooves are formed on the inner periphery of the hammer housing 4. The bearing housing 24 and the hammer housing 4 are fixed by the engagement of the threaded teeth of the bearing housing 24 and the threaded grooves of the hammer housing 4. The hammer housing 4 is held by the left outer shell 2L and the right outer shell 2R. At least a portion of the hammer housing 4 is housed in the motor housing 21. The bearing housing 24 is fixed to both the motor housing 21 and the hammer housing 4.

[0054] The hammer housing 4 is used to house at least a portion of the reduction mechanism 7, the main shaft 8, the striking mechanism 9, and the anvil 10. At least a portion of the reduction mechanism 7 is located inside the bearing housing 24. The reduction mechanism 7 includes multiple gears.

[0055] The hammer housing 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 further forward than 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.

[0056] The hammer housing cover 5 covers at least a portion of the surface of the hammer housing 4. The hammer housing cover 5 is used to protect the hammer housing 4. The hammer housing cover 5 is used to prevent the hammer housing 4 from coming into contact with surrounding objects.

[0057] Motor 6 is the power source for impact tool 1. Motor 6 is an internal rotor type brushless motor. Motor 6 has a stator 26 and a rotor 27. Stator 26 is supported in motor housing 21. At least a portion of rotor 27 is disposed inside stator 26. Rotor 27 rotates relative to stator 26. Rotor 27 rotates about a rotation axis AX extending in the front-rear direction.

[0058] The stator 26 includes: a stator core 28, a front insulator 29, a rear insulator 30, and a coil 31.

[0059] The stator core 28 is positioned radially outward from the rotor 27. The stator core 28 comprises multiple stacked steel plates. The steel plates are plates made of a metal primarily composed of iron. The stator core 28 is cylindrical. The stator core 28 has multiple teeth for supporting the coils 31.

[0060] The front insulator 29 is located at the front of the stator core 28. The rear insulator 30 is located at the rear of the stator core 28. Both the front insulator 29 and the rear insulator 30 are electrical insulation components made of synthetic resin. The front insulator 29 is configured to cover a portion of the tooth surface. The rear insulator 30 is configured to cover a portion of the tooth surface.

[0061] Coil 31 is mounted on stator core 28 via front insulator 29 and rear insulator 30. Multiple coils 31 are arranged. Coil 31 are arranged around the teeth of stator core 28 via front insulator 29 and rear insulator 30. Coil 31 and stator core 28 are electrically insulated by front insulator 29 and rear insulator 30. Multiple coils 31 are connected by fusible terminals 38.

[0062] The rotor 27 rotates around the rotation axis AX. The rotor 27 includes: a rotor core 32, a rotor shaft 33, a rotor magnet 34, and a sensor magnet 35.

[0063] The rotor core 32 and the rotor shaft 33 are both made of steel. The rotor shaft 33 protrudes from the end face of the rotor core 32 in a front-rear direction. The rotor shaft 33 includes a front shaft 33F protruding forward from the front end face of the rotor core 32 and a rear shaft 33R protruding rearward from the rear end face of the rotor core 32.

[0064] The rotor magnet 34 is fixed to the rotor core 32. The rotor magnet 34 is cylindrical. The rotor magnet 34 is disposed around the rotor core 32.

[0065] The sensor magnet 35 is fixed to the rotor core 32. The sensor magnet 35 is ring-shaped. The sensor magnet 35 is disposed on the front end face of the rotor core 32 and the front end face of the rotor magnet 34.

[0066] A sensor substrate 37 is mounted on the front insulator 29. The sensor substrate 37 is fixed to the front insulator 29 by screws 29S. The sensor substrate 37 has: a circular plate-shaped circuit board with a hole in the center; and a rotation detection element supported on the circuit board. At least a portion of the sensor substrate 37 is opposite to the sensor magnet 35. The rotation detection element detects the position of the rotation direction of the rotor 27 by detecting the position of the sensor magnet 35 on the rotor 27.

[0067] The rotor shaft 33 is rotatably supported on the rotor bearing 39. The rotor bearing 39 includes a front rotor bearing 39F that supports the front shaft 33F and is rotatable, and a rear rotor bearing 39R that supports the rear shaft 33R and is rotatable.

[0068] The front rotor bearing 39F is held in the bearing housing 24. The bearing housing 24 has a recess 24A that is recessed from the rear surface of the bearing housing 24 toward the front. The front rotor bearing 39F is disposed in the recess 24A. The rear rotor bearing 39R is held in the rear cover 3. The front end of the rotor shaft portion 33 is disposed in the internal space of the hammer housing 4 through the opening of the bearing housing 24.

[0069] A pinion 41 is formed at the front end of the rotor shaft portion 33. The pinion 41 is connected to at least a portion of the reduction mechanism 7. The rotor shaft portion 33 is connected to the reduction mechanism 7 by means of the pinion 41.

[0070] The reduction mechanism 7 is positioned further forward than the motor 6. The reduction mechanism 7 connects the rotor shaft 33 to the main shaft 8. The reduction mechanism 7 transmits the rotation of the rotor 27 to the main shaft 8. The reduction mechanism 7 causes the main shaft 8 to rotate at a speed lower than the rotational speed of the rotor shaft 33. The reduction mechanism 7 includes a planetary gear mechanism.

[0071] The reduction mechanism 7 has multiple gears. The gears of the reduction mechanism 7 are driven by the rotor 27.

[0072] The reduction mechanism 7 includes a plurality of planetary gears 42 arranged around a pinion 41, and an internal gear 43 arranged around the plurality of planetary gears 42. The pinion 41, planetary gears 42, and internal gear 43 are each housed within a hammer housing 4. The plurality of planetary gears 42 mesh with the pinion 41. The planetary gears 42 are rotatably supported on a main shaft 8 by means of pins 42P. The main shaft 8 rotates via the planetary gears 42. The internal gear 43 has internal teeth that mesh with the planetary gears 42. The internal gear 43 is fixed to the hammer housing 4. The internal gear 43 cannot rotate relative to the hammer housing 4.

[0073] When the rotor shaft 33 is rotated by the drive of the motor 6, the pinion 41 rotates, causing the planetary gear 42 to revolve around the pinion 41. The planetary gear 42 revolves while meshing with the internal teeth of the internal gear 43. The revolution of the planetary gear 42 causes the main shaft 8, connected to the planetary gear 42 by means of pin 42P, to rotate at a speed lower than the rotational speed of the rotor shaft 33.

[0074] The main shaft 8 is positioned further forward than at least a portion of the motor 6. The main shaft 8 is positioned further forward than the stator 26. At least a portion of the main shaft 8 is positioned further forward than the rotor 27. At least a portion of the main shaft 8 is positioned in front of the reduction gear 7. The main shaft 8 is positioned behind the anvil 10. The main shaft 8 rotates via the rotor 27. The main shaft 8 rotates via the rotational force of the rotor 27 transmitted by the reduction gear 7. The main shaft 8 transmits the rotational force of the motor 6 to the anvil 10 via the balls 48 and the hammers 47.

[0075] The spindle 8 has a flange portion 8A and a spindle shaft portion 8B protruding forward from the flange portion 8A. The planetary gear 42 is rotatably supported on the flange portion 8A by means of a pin 42P. The rotation axis of the spindle 8 is aligned with the rotation axis AX of the motor 6. The spindle 8 rotates about the rotation axis AX. The spindle 8 is rotatably supported on a spindle bearing 44. A protrusion 8C is provided at the rear end of the spindle 8. The protrusion 8C protrudes rearward from the flange portion 8A. The protrusion 8C is configured to surround the spindle bearing 44.

[0076] The bearing housing 24 is disposed around at least a portion of the spindle 8. The spindle bearing 44 is held in the bearing housing 24. The bearing housing 24 has a protrusion 24B projecting forward from the front surface of the bearing housing 24. The spindle bearing 44 is disposed around the protrusion 24B.

[0077] 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 reduction mechanism 7 and the main shaft 8. The striking mechanism 9 strikes the anvil 10 in the direction of rotation based on the rotational force of the main shaft 8, which is rotated by the motor 6. The striking mechanism 9 includes: a hammer 47, a ball bearing 48, a first helical spring 49, a second helical spring 50, a third helical spring 51, a first washer 52, and a second washer 53. The striking mechanism 9, including the hammer 47, ball bearing 48, first helical spring 49, second helical spring 50, third helical spring 51, first washer 52, and second washer 53, is housed in the first cylindrical portion 401 of the hammer housing 4.

[0078] Hammer 47 is positioned further forward than reduction mechanism 7. Hammer 47 is positioned around spindle 8. Hammer 47 is held on spindle 8. Ball bearing 48 is positioned between spindle 8 and hammer 47. Hammer 47 has a cylindrical hammer body 47D and a hammer protrusion 47E located at the front of hammer body 47D. An annular recess 47C is provided on the rear surface of hammer body 47D. Recess 47C is recessed from the rear surface of hammer body 47D towards the front.

[0079] Hammer 47 is disposed around spindle shaft portion 8B. Hammer 47 has a hole 47A for mounting spindle shaft portion 8B.

[0080] Hammer 47 is rotated by motor 6. The rotational force of motor 6 is transmitted to hammer 47 via reduction gear 7 and main shaft 8. Hammer 47 can rotate together with main shaft 8 based on the rotational force of main shaft 8 rotated by motor 6. The rotation axis of hammer 47, the rotation axis of main shaft 8, and the rotation axis AX of motor 6 are aligned. Hammer 47 rotates around rotation axis AX.

[0081] The first washer 52 is positioned inside the recess 47C. The first washer 52 is supported on the hammer 47 by means of a plurality of balls 54. The balls 54 are positioned further forward than the first washer 52.

[0082] The second washer 53 is located inside the recess 47C, positioned further rearward than the first washer 52. The outer diameter of the second washer 53 is smaller than that of the first washer 52. The second washer 53 and the hammer 47 are movable relative to each other in the front-to-back direction.

[0083] The first helical spring 49 is disposed around the spindle shaft portion 8B. The rear end of the first helical spring 49 is supported by the flange portion 8A. The front end of the first helical spring 49 is disposed inside the recess 47C and is supported by the first washer 52. The first helical spring 49 always generates a spring force for moving the hammer 47 forward.

[0084] The second helical spring 50 is disposed around the spindle shaft portion 8B. The second helical spring 50 is disposed radially inward of the first helical spring 49. The rear end of the second helical spring 50 is supported by the flange portion 8A. The front end of the second helical spring 50 is disposed inside the recess 47C and is supported by the second washer 53. When the hammer 47 moves rearward, the second helical spring 50 generates a spring force for moving the hammer 47 forward.

[0085] The third helical spring 51 is disposed around the main shaft portion 8B. The third helical spring 51 is disposed radially inward of the first helical spring 49. The third helical spring 51 is disposed inward of the recess 47C. The rear end of the third helical spring 51 is supported by the second washer 53. The front end of the third helical spring 51 is supported by the first washer 52. The third helical spring 51 generates a spring force for moving the second helical spring 50 rearward. Due to the spring force of the third helical spring 51, the rear end of the second helical spring 50 is pressed against the flange portion 8A. Therefore, it is possible to suppress the second helical spring 50 from floating relative to the flange portion 8A.

[0086] The ball bearing 48 is made of a metal such as steel. The ball bearing 48 is positioned between the spindle shaft portion 8B and the hammer 47. The spindle 8 has a spindle groove 8D for at least a portion of the ball bearing 48. The spindle groove 8D is located on a portion of the outer surface of the spindle shaft portion 8B. The hammer 47 has a hammer groove 47B for at least a portion of the ball bearing 48. The hammer groove 47B is located on a portion of the inner surface of the hammer 47. The ball bearing 48 is positioned between the spindle groove 8D and the hammer groove 47B. The ball bearing 48 can roll on the inner side of both the spindle groove 8D and the hammer groove 47B. The hammer 47 can move along with the ball bearing 48. The spindle 8 and the hammer 47 can move relative to each other along the axial and rotational directions within the movable range defined by the spindle groove 8D and the hammer groove 47B, respectively.

[0087] The anvil 10 is positioned further forward than the motor 6. The anvil 10 is the output part of the impact tool 1, which rotates based on the rotational force of the rotor 27. At least a portion of the anvil 10 is positioned further forward than the hammer 47. The anvil 10 has a tool hole 10A for inserting a front-end tool. The tool hole 10A is located at the front end of the anvil 10. The front-end tool is fitted onto the anvil 10.

[0088] The anvil 10 has an anvil protrusion 10B. The anvil protrusion 10B is located at the rear end of the anvil 10. The anvil protrusion 10B protrudes rearward from the rear end of the anvil 10. A spindle 8 is disposed at the rear of the anvil 10. A spindle recess 8E is provided at the front end of the spindle shaft portion 8B. The anvil protrusion 10B is disposed in the spindle recess 8E.

[0089] The anvil 10 has a rod-shaped anvil shaft portion 101 and an anvil protrusion 102. A tool hole 10A is provided at the front end of the anvil shaft portion 101. A front-end tool is fitted to the anvil shaft portion 101. The anvil protrusion 102 is provided at the rear end of the anvil 10. The anvil protrusion 102 protrudes radially outward from the rear end of the anvil shaft portion 101.

[0090] The anvil 10 is rotatably supported by the bearing 46. The rotation axis of the anvil 10, the rotation axis of the hammer 47, the rotation axis of the main shaft 8, and the rotation axis AX of the motor 6 are aligned. The anvil 10 rotates around the rotation axis AX. The bearing 46 is disposed around the anvil shaft portion 101. The bearing 46 is disposed inside the second cylindrical portion 402 of the hammer housing 4. The bearing 46 is held in the second cylindrical portion 402 of the hammer housing 4. The bearing 46 supports the front part of the anvil shaft portion 101 so that it can rotate. An O-ring 45 is disposed between the bearing 46 and the anvil shaft portion 101.

[0091] In this embodiment, two bearings 46 are arranged axially. In the following description, the two bearings 46 will be appropriately referred to as bearing 46A and bearing 46B, respectively. Bearing 46A is positioned further forward than bearing 46B.

[0092] Furthermore, in this embodiment, two O-rings 45 are arranged axially. In the following description, the two O-rings 45 will be appropriately referred to as O-ring 45A and O-ring 45B, respectively. O-ring 45A is positioned further forward than O-ring 45B. O-ring 45A is positioned between bearing 46A and anvil shaft portion 101. O-ring 45B is positioned between bearing 46B and anvil shaft portion 101.

[0093] At least a portion of the hammer 47 can contact the anvil protrusion 102. A forward-protruding hammer protrusion 47E is provided at the front of the hammer 47. The hammer protrusion 47E can contact the anvil protrusion 102. When the hammer 47 is in contact with the anvil protrusion 102, it is driven by the motor 6, causing the anvil 10, hammer 47, and spindle 8 to rotate together.

[0094] The anvil 10 is struck in the direction of rotation by the hammer 47. For example, in screw tightening operations, if the load acting on the anvil 10 becomes high, a situation may occur where the anvil 10 cannot rotate due to the load of the first coil spring 49 alone. When the anvil 10 cannot rotate due to the load of the first coil spring 49 alone, the rotation of the anvil 10 and the hammer 47 will stop. The spindle 8 and the hammer 47 can move relative to each other in the axial and circumferential directions by means of the balls 48. Even if the rotation of the hammer 47 stops, the rotation of the spindle 8 will continue due to the power generated by the motor 6. When the rotation of the hammer 47 stops, as the spindle 8 rotates, the balls 48 move backward while being guided through the spindle groove 8D and the hammer groove 47B respectively. The hammer 47 is subjected to force from the balls 48 and moves backward along with the balls 48. That is, with the rotation of the anvil 10 stopped, the hammer 47 moves backward due to the rotation of the spindle 8. As the hammer 47 moves backward, the contact between the hammer 47 and the anvil protrusion 102 is released.

[0095] As described above, the first helical spring 49 consistently generates a spring force that moves the hammer 47 forward. The second helical spring 50 generates a spring force that moves the hammer 47 forward after the hammer 47 has moved to a position further back than a predetermined position. The hammer 47, now in a rearward position, moves forward due to the spring forces of the first helical spring 49 and the second helical spring 50. As the hammer 47 moves forward, it receives a force in the direction of rotation from the ball bearing 48. That is, the hammer 47 rotates while moving forward. While rotating and moving forward, the hammer 47 contacts the anvil protrusion 102. Thus, the anvil protrusion 102 is struck in the direction of rotation by the hammer protrusion 47E of the hammer 47. The anvil 10 is acted upon by both the power of the motor 6 and the inertial force of the hammer 47. Therefore, the anvil 10 can rotate around the rotation axis AX with a high torque.

[0096] The tool holding mechanism 11 is disposed around the front portion of the anvil 10. The tool holding mechanism 11 holds the front-end tool inserted into the tool hole 10A of the anvil 10. The tool holding mechanism 11 allows for the attachment and removal of the front-end tool.

[0097] The tool holding mechanism 11 includes: a ball bearing 71, a leaf spring 72, a sleeve 73, a coil spring 74, and a positioning component 75.

[0098] 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 this embodiment, two support recesses 76 are formed on the anvil shaft portion 101.

[0099] The ball 71 is movably supported on the anvil 10. The ball 71 is disposed in the support recess 76. One ball 71 is disposed in one support recess 76.

[0100] A through hole is formed in the anvil shaft portion 101 for connecting the inner surface of the support recess 76 to the inner surface of the tool hole 10A. The diameter of the ball 71 is smaller than the diameter of the through hole. With the ball 71 supported in the support recess 76, it is positioned inside the tool hole 10A by means of at least a portion of the ball 71. The ball 71 can fix the front end tool inserted into the tool hole 10A. The ball 71 can move to an engaged position for fixing the front end tool and a released position for releasing the fixing of the front end tool.

[0101] The leaf spring 72 generates a spring force to move the ball 71 toward the engaging position. The leaf spring 72 is disposed around the anvil shaft portion 101. The leaf spring 72 generates a spring force to move the ball 71 forward.

[0102] Sleeve 73 is a cylindrical component. Sleeve 73 is disposed around the anvil shaft portion 101. Sleeve 73 is movable axially around the anvil shaft portion 101. Sleeve 73 prevents the ball 71, which is positioned in the engaged position, from disengaging from the engaged position. By moving axially, sleeve 73 allows the ball 71 to change to a state where it can move from the engaged position toward the disengaged position.

[0103] The sleeve 73 can move around the anvil shaft portion 101 to: a blocking position that prevents the ball 71 from moving radially outward, and a permissive position that allows the ball 71 to move radially outward.

[0104] By positioning the sleeve 73 in the blocking position, it is possible to prevent the ball 71, which is positioned in the engaging position, from moving radially outward. In other words, by positioning the sleeve 73 in the blocking position, it is possible to prevent the ball 71, which is positioned in the engaging position, from disengaging from the engaging position. By positioning the sleeve 73 in the blocking position, it is possible to maintain the state in which the front-end tool is fixed by the ball 71.

[0105] By moving the sleeve 73 toward the allowable position, it is possible for the ball 71, which is positioned in the engaged position, to move radially outward. Moving the sleeve 73 toward the allowable position changes the ball 71 to a state where it can move from the engaged position toward the disengaged position. That is, by positioning the sleeve 73 in the allowable position, it is possible for the ball 71, which is positioned in the engaged position, to disengage from the engaged position. By positioning the sleeve 73 in the allowable position, it is possible to release the state in which the front-end tool is fixed by the ball 71.

[0106] The coil spring 74 generates a spring force to move the sleeve 73 toward the stop position. The coil spring 74 is disposed around the anvil shaft portion 101. The stop position is defined as a position further rearward than the permissible position. The coil spring 74 generates a spring force for moving the sleeve 73 rearward.

[0107] The positioning member 75 is an annular member fixed to the outer surface of the anvil shaft portion 101. The positioning member 75 is fixed in a position opposite to the rear end of the sleeve 73. The positioning member 75 positions the sleeve 73 in a stopped position. The sleeve 73, which is given a rearward elastic force by the coil spring 74, is positioned in the stopped position by contacting the positioning member 75.

[0108] The fan 12 is positioned further rearward than the stator 26 of the motor 6. The fan 12 generates airflow for cooling the motor 6. The fan 12 is fixed to at least a portion of the rotor 27. The fan 12 is fixed to the rear of the rear shaft portion 33R by means of a bushing 12A. The fan 12 is positioned between the rear rotor bearing 39R and the stator 26. The fan 12 rotates as the rotor 27 rotates. The fan 12 rotates together with the rotor shaft portion 33 as the rotor shaft portion 33 rotates. As the fan 12 rotates, air from the external space of the housing 2 flows into the internal space of the housing 2 through the air inlet 19. The air flowing into the internal space of the housing 2 cools the motor 6 by circulating within the internal space of the housing 2. The air circulating within the internal space of the housing 2 is rotated by the fan 12 and then flows out to the external space of the housing 2 through the exhaust port 20.

[0109] The battery assembly section 13 is disposed at the lower part of the battery holding section 23. The battery assembly section 13 is connected to the battery pack 25. The battery pack 25 is assembled in the battery assembly section 13. The battery pack 25 is detachable from the battery assembly section 13. The battery pack 25 is assembled in the battery assembly section 13 by being inserted into it from the front of the battery holding section 23. The battery pack 25 is removed from the battery assembly section 13 by being pulled forward from it. The battery pack 25 includes a secondary battery. In this embodiment, the battery pack 25 includes a rechargeable lithium-ion battery. The battery pack 25, by being assembled in the battery assembly section 13, can supply power to the impact tool 1. The motor 6 is driven by the power supplied from the battery pack 25. The operation display section 16 operates by the power supplied from the battery pack 25.

[0110] A trigger lever 14 is provided on the grip 22. The trigger lever 14 is operated by the operator to start the motor 6. By operating the trigger lever 14, the driving and stopping of the motor 6 can be switched.

[0111] A forward / reverse switching lever 15 is located on the upper part of the handle 22. The forward / reverse switching lever 15 is operated by the operator. By operating the forward / reverse switching lever 15, the rotation direction of the motor 6 is switched from either the forward or reverse direction. Switching the rotation direction of the motor 6 also switches the rotation direction of the spindle 8.

[0112] An operation display unit 16 is provided on the battery holding unit 23. The operation display unit 16 is located on the upper surface of the battery holding unit 23, further forward than the handle unit 22. The operation display unit 16 includes multiple operation buttons 16A and an indicator light display 16B. The operator switches the operating mode of the motor 6 by operating the operation buttons 16A. The indicator light display 16B includes multiple light-emitting parts. The indicator light display 16B displays the operating mode of the motor 6 by changing the illumination pattern of the multiple light-emitting parts.

[0113] The mode switching switch 17 is located on the upper part of the trigger lever 14. The mode switching switch 17 is operated by the operator to switch the operating mode of the motor 6.

[0114] The lamp assembly 18 emits illumination light. The lamp assembly 18 illuminates the anvil 10 and its periphery. The lamp assembly 18 also illuminates the front of the anvil 10. Additionally, the lamp assembly 18 illuminates the front tool mounted on the anvil 10 and its periphery. In this embodiment, the lamp assembly 18 includes an annular base member 18A and a plurality of light-emitting elements 18B held in the base member 18A. The base member 18A is disposed around the second cylindrical portion 402 of the hammer housing 4. Furthermore, the lamp assembly 18 has an annular member 18C for preventing the base member 18A from falling forward from the second cylindrical portion 402.

[0115] <Ring-shaped component and suppression component>

[0116] Figure 5 It is Figure 4 The image is an enlarged version of a portion of the image. Figure 6 This is an exploded perspective view showing a portion of the impact tool 1 involved in the embodiment.

[0117] like Figure 3 , Figure 4 , Figure 5 ,as well as Figure 6 As shown, the impact tool 1 includes: a hammer housing 4, a bearing 46, an O-ring 45, an annular component 61, and a suppressing component 62.

[0118] The hammer housing 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 further forward than 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. A bearing 46 is held in the hammer housing 4. The bearing 46 is disposed inside the second cylindrical portion 402 of the hammer housing 4.

[0119] Bearing 46 is disposed around the anvil shaft portion 101. O-ring 45 is disposed between the outer periphery of the anvil shaft portion 101 and the inner periphery of the bearing 46. O-ring 45 contacts both the outer periphery of the anvil shaft portion 101 and the inner periphery of the bearing 46. Bearing 46 supports the anvil shaft portion 101 for rotation. As described above, two bearings 46 are disposed in the longitudinal direction. Two O-rings 45 are disposed in the longitudinal direction. Bearing 46 includes bearing 46A and bearing 46B disposed further rearward than bearing 46A. O-ring 45 includes O-ring 45A and O-ring 45B disposed further rearward than O-ring 45A. O-ring 45A is disposed between bearing 46A and anvil shaft portion 101. O-ring 45B is disposed between bearing 46B and anvil shaft portion 101.

[0120] Bearing 46 is a ball bearing. Bearings 46A and 46B each have an inner ring 46C, balls 46D, and an outer ring 46E. The inner ring 46C of bearing 46A contacts an O-ring 45A. The inner ring 46C of bearing 46B contacts an O-ring 45B. Balls 46D are radially positioned between the inner ring 46C and the outer ring 46E. Balls 46D contact both the inner ring 46C and the outer ring 46E. Multiple balls 46D are arranged circumferentially. The outer ring 46E is positioned radially outward from the inner ring 46C and the balls 46D. The outer ring 46E of bearing 46A contacts the inner circumferential surface of the second cylinder portion 402. The outer ring 46E of bearing 46B contacts the inner circumferential surface of the second cylinder portion 402.

[0121] The annular component 61 is a belt-shaped component. The annular component 61 is made of metal. Iron is shown as an example of the metal used to form the annular component 61. The front and rear surfaces of the annular component 61 are flat.

[0122] In the longitudinal direction, the annular member 61 is positioned between the anvil protrusion 102 and the rear bearing 46B. The bearing 46B is positioned further forward than the annular member 61. The anvil protrusion 102 is positioned further rearward than the annular member 61. At least a portion of the rear surface of the annular member 61 is configured to face the front surface of the anvil protrusion 102. At least a portion of the front surface of the annular member 61 is configured to contact the rear end face of the rear bearing 46B.

[0123] The suppressing member 62 engages with both the hammer housing 4 and the annular member 61. The suppressing member 62 is used to suppress the annular member 61 from falling off rearward. Examples of the suppressing member 62 include a retaining ring or a C-ring. The suppressing member 62 is configured to contact the annular member 61.

[0124] The hammer housing 4 has a support surface 4A opposite to at least a portion of the front surface of the annular member 61, and an inner circumferential surface 4C opposite to the outer circumferential surface of the annular member 61. The support surface 4A of the hammer housing 4 and the rear end face of the rear bearing 46 are substantially disposed in the same plane. At least a portion of the annular member 61 is disposed between the front surface of the anvil protrusion 102 and the support surface 4A of the hammer housing 4.

[0125] The annular component 61 is used to suppress contact between the hammer housing 4 and the anvil protrusion 102.

[0126] At least a portion of the front surface of the annular component 61 contacts the support surface 4A of the hammer housing 4. Additionally, at least a portion of the front surface of the annular component 61 contacts the rear end face of the bearing 46B.

[0127] like Figure 5 As shown, the outer edge 61A of the front surface of the annular member 61 contacts the support surface 4A of the hammer housing 4. The outer peripheral surface of the annular member 61 can contact the inner peripheral surface 4C of the hammer housing 4. The inner edge 61B of the front surface of the annular member 61 can contact the rear end face of the outer ring 46E of the bearing 46B. The annular member 61 is positioned radially outward from the inner ring 46C of the bearing 46B. The annular member 61 does not contact the inner ring 46C of the bearing 46B.

[0128] The outer edge of the rear surface of the annular component 61, 61C, is in contact with the suppressing component 62.

[0129] A groove 4B is provided on the inner surface of the first cylindrical portion 401 of the hammer housing 4 for at least a portion of the suppressing member 62 to engage. The hammer housing 4 has a first support surface 4D connected to the rear end of the inner peripheral surface 4C, a second support surface 4E disposed further rearward than 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 outward than the inner peripheral surface 4C. The second support surface 4E faces forward. The second support surface 4E is opposite to the first support surface 4D. The inner peripheral surface 4F is configured to connect the radially outer end of the first support surface 4D to the radially outer end of the second support surface 4E. The first support surface 4D can be opposite to the outer edge of the front surface of the suppressing member 62. The second support surface 4E can be opposite to the outer edge of the rear surface of the suppressing member 62. The inner peripheral surface 4F can be opposite to the outer peripheral surface of the suppressing member 62. The groove 4B is defined by the first support surface 4D, the second support surface 4E, and the inner circumferential surface 4F. By distributing the suppressing member 62 in the groove 4B, at least the axial displacement of the hammer housing 4 and the suppressing member 62 can be suppressed.

[0130] The annular component 61 and the suppressing component 62 prevent the bearing 46 from moving backward (to the other side of the axial direction).

[0131] like Figure 3 As shown, the outer edge of the front surface of the anvil protrusion 102, the outer edge of the front surface 102A, tends to be radially outward and tilts backward.

[0132] In the front-rear direction, the suppressing member 62 is positioned between the outer edge of the front surface of the anvil protrusion 102 and the outer edge of the rear surface of the annular member 61.

[0133] <Action of the impact tool>

[0134] Next, the operation of the impact tool 1 will be explained. For example, when performing screw tightening operations on the work object, the front tool (screwdriver bit) used in the screw tightening operation is inserted into the tool hole 10A of the anvil 10. The front tool inserted into the tool hole 10A is held by the tool holding mechanism 11. After the front tool is assembled into the anvil 10, the operator, for example, holds the handle 22 with his right hand and pulls the trigger lever 14 with his right index finger. Once the trigger lever 14 is pulled, power is supplied from the battery pack 25 to the motor 6, thereby starting the motor 6 and illuminating the lamp assembly 18. With the start of the motor 6, the rotor shaft 33 of the rotor 27 rotates. Once the rotor shaft 33 rotates, the rotational force of the rotor shaft 33 is transmitted to the planetary gear 42 via the pinion 41. The planetary gear 42, in a state of meshing with the internal teeth of the internal gear 43, rotates on its own axis while revolving around the pinion 41. The planetary gear 42 is rotatably supported on the main shaft 8 by means of pin 42P. Through the revolution of the planetary gear 42, the main shaft 8 rotates at a speed lower than that of the rotor shaft 33.

[0135] With the hammer 47 in contact with the anvil protrusion 102, when the spindle 8 rotates, the anvil 10 will rotate together with the hammer 47 and the spindle 8. The screw tightening operation can be performed by rotating the anvil 10.

[0136] When a load exceeding a specified value is applied to the anvil 10 during screw tightening, the rotation of the anvil 10 and the hammer 47 stops. With the hammer 47 stopped rotating, the hammer 47 moves rearward as the spindle 8 rotates. This rearward movement of the hammer 47 releases the contact between the hammer 47 and the anvil protrusion 102. The hammer 47, now in the rearward position, is moved forward while rotating due to the force of the first coil spring 49 and the second coil spring 50. As the hammer 47 rotates and moves forward, the anvil 10 is struck in the direction of rotation by the hammer 47. Consequently, the anvil 10 rotates around the rotation axis AX with a high torque. Therefore, the screw can be tightened to the workpiece with a high torque.

[0137] <Effect>

[0138] As described above, in this embodiment, the impact tool 1 includes: a motor 6; a striking mechanism 9 driven by the motor 6; an anvil 10 having an anvil shaft 101 for mounting a front tool and an anvil protrusion 102 protruding radially outward from the rear end of the anvil shaft 101 and struck in the direction of rotation by the striking mechanism 9; a hammer housing 4 for housing the striking mechanism 9; a bearing 46 held in the hammer housing 4 and disposed around the anvil shaft 101; an annular member 61 disposed with at least a portion facing the front surface of the anvil protrusion 102 and in contact with the rear end face of the bearing 46; and a restraining member 62 engaged with the hammer housing 4 and the annular member 61 and used to prevent the annular member 61 from falling off rearward.

[0139] In the above configuration, the annular member 61 contacts the rear end face of the bearing 46, so the bearing 46 is supported by the annular member 61. The annular member 61 can be prevented from falling rearward by the suppressing member 62. The bearing 46 is supported by the suppressing member 62 by means of the annular member 61, so the situation of the bearing 46 falling rearward can be prevented. The bearing 46 is supported by the annular member 61, and the annular member 61 is supported by the suppressing member 62, so the enlargement of the impact tool 1 can be prevented. In particular, the situation where the upper dimension of the impact tool 1 in the axial direction parallel to the rotation axis AX of the motor 6 becomes larger can be prevented. For example, the situation where the axial length, which represents the distance between the rear end face of the rear cover 3 and the front end face of the anvil shaft portion 101, becomes longer can be prevented.

[0140] In one embodiment, the hammer housing 4 has a support surface 4A opposite to at least a portion of the front surface of the annular member 61, and at least a portion of the annular member 61 is disposed at a position between the front surface of the anvil protrusion 102 and the support surface 4A of the hammer housing 4.

[0141] In the above configuration, the annular member 61 is supported by being clamped in the front-rear direction by the support surface 4A of the hammer housing 4 and the suppressing member 62. This suppresses any movement of the annular member 61 relative to the hammer housing 4. The bearing 46 is stably supported on the annular member 61.

[0142] In one embodiment, the annular component 61 is used to suppress contact between the hammer housing 4 and the anvil protrusion 102.

[0143] In the above configuration, the contact between the hammer housing 4 and the anvil protrusion 102 can be suppressed by the annular member 61 positioned between the hammer housing 4 and the anvil protrusion 102.

[0144] In one embodiment, at least a portion of the front surface of the annular component 61 is in contact with the support surface 4A of the hammer housing 4.

[0145] In the above configuration, the front surface of the annular component 61 is in direct contact with the support surface 4A of the hammer housing 4, thus preventing the impact tool 1 from becoming too large in the axial direction. That is, it can prevent the shaft length from increasing.

[0146] In the embodiment, the outer edge of the front surface 61A, representing the outer edge of the front surface of the annular component 61, is in contact with the support surface 4A of the hammer housing 4, and the inner edge of the front surface 61B, representing the inner edge of the front surface of the annular component 61, is in contact with the rear end face of the bearing 46.

[0147] In the above configuration, the support surface 4A of the hammer housing 4 and the rear end face of the bearing 46 are substantially disposed on the same plane, and the front surface of the annular member 61 contacts both the support surface 4A of the hammer housing 4 and the rear end face of the bearing 46. Therefore, the bearing 46 can be stably supported by the annular member 61, thereby preventing the impact tool 1 from becoming too large in the axial direction. That is, it can prevent the shaft length from increasing.

[0148] In the embodiment, the outer edge of the rear surface of the annular member 61, denoted as the outer edge of the rear surface, is in contact with the suppression member 62.

[0149] In the above configuration, the rear surface of the annular member 61 is in direct contact with the suppressing member 62, thus suppressing the axial enlargement of the impact tool 1. That is, it can suppress the situation where the shaft length increases.

[0150] In one embodiment, a groove 4B is provided on the inner surface of the hammer housing 4 for at least a portion of the suppressing member 62 to engage.

[0151] In the above configuration, it is possible to suppress: the change in the relative position of the hammer housing 4 and the suppression component 62 in the axial direction.

[0152] In the embodiment, in the front-rear direction, the suppressing member 62 is positioned between the outer edge of the front surface of the anvil protrusion 102 (representing the outer edge of the front surface of the anvil protrusion 102) and the outer edge of the rear surface of the annular member 61.

[0153] In the above structure, the contact between the anvil protrusion 102 and the annular member 61 can be suppressed by the suppressing member 62 positioned between the anvil protrusion 102 and the annular member 61.

[0154] In one embodiment, the outer edge 102A of the front surface of the anvil protrusion 102 tends to be radially outward and tilted rearward.

[0155] In the above configuration, it is possible to suppress the contact between the outer edge 102A of the front surface of the anvil protrusion 102 and the suppression member 62.

[0156] In one embodiment, the hammer housing 4 has a first cylindrical portion 401 disposed around the striking mechanism 9, and a second cylindrical portion 402 disposed further forward than the first cylindrical portion 401 and having an outer diameter smaller than that of the first cylindrical portion 401. The bearing 46 is held in the second cylindrical portion 402.

[0157] In the above configuration, the bearing 46 can be stably held in the second cylindrical portion 402.

[0158] <Variation Example>

[0159] In the above embodiment, the impact tool 1 is an impact screwdriver. The impact tool 1 can also be an impact wrench.

[0160] In the above embodiments, the power source for the impact tool 1 may not be the battery pack 25, but may be a commercial power source (AC power).

Claims

1. An impact tool, characterized in that, The impact tool has the following features: motor; The striking mechanism is driven by the motor. An anvil has an anvil shaft portion for mounting a front tool, and an anvil protrusion portion that protrudes radially outward from the rear end of the anvil shaft portion and is struck in the direction of rotation by the striking mechanism. A hammer housing for housing the striking mechanism; A bearing is held in the hammer housing and disposed around the anvil shaft portion; An annular component, which is configured such that at least a portion of it is opposite to the front surface of the anvil protrusion and contacts the rear end face of the bearing; as well as A suppressing component, which engages with the hammer housing and the annular component, and is used to suppress the annular component from falling off backward. The hammer housing has: a first cylindrical portion disposed around the striking mechanism, and a second cylindrical portion disposed further forward than the first cylindrical portion and having an outer diameter smaller than the outer diameter of the first cylindrical portion. The inner surface of the first cylindrical portion of the hammer housing is provided with a groove for at least a portion of the suppressing member to engage. In the radial direction, the outer peripheral surface of the annular component is positioned further outward than the outer peripheral surface of the second cylindrical portion.

2. The impact tool according to claim 1, characterized in that, The hammer housing has a support surface opposite to at least a portion of the front surface of the annular component. At least a portion of the annular component is positioned between the front surface of the anvil protrusion and the support surface of the hammer housing.

3. The impact tool according to claim 2, characterized in that, The annular component is used to suppress contact between the hammer housing and the anvil protrusion.

4. The impact tool according to claim 2 or 3, characterized in that, At least a portion of the front surface of the annular component is in contact with the support surface of the hammer housing.

5. The impact tool according to claim 2 or 3, characterized in that, The outer edge of the front surface of the annular component contacts the supporting surface of the hammer housing. The inner edge of the front surface of the annular component contacts the rear end face of the bearing.

6. The impact tool according to claim 2 or 3, characterized in that, The outer edge of the rear surface of the annular component comes into contact with the suppressing component.

7. The impact tool according to claim 2 or 3, characterized in that, In the front-rear direction, the suppressing member is positioned between the outer edge of the front surface of the anvil protrusion and the outer edge of the rear surface of the annular member.

8. The impact tool according to claim 7, characterized in that, The outer edge of the front surface of the anvil protrusion tends to be radially outward and tilted backward.

9. The impact tool according to claim 2 or 3, characterized in that, The bearing is held in the second cylindrical section.

Images