JP2023061296A - impact tool - Google Patents

Abstract

To suppress an anvil from coming off.SOLUTION: An impact tool comprises: a motor; a striking mechanism that can rotate with an output rotary shaft extending in a longitudinal direction as the center and is driven by the motor; an anvil which has an anvil shaft part arranged closer to a front side than the striking mechanism and an anvil protrusion part that protrudes outward in a radial direction from a rear end part of the anvil shaft part and is struck by the striking mechanism in a rotating direction with the output rotary shaft as the center; a hammer case for storing the striking mechanism; an anvil bearing held on the hammer case and arranged around the anvil shaft part; a first groove part formed on an outer peripheral surface of the anvil shaft part to surround the output rotary shaft; a second groove part formed on an inner peripheral surface of the anvil bearing to surround the output rotary shaft; and a suppressing member including a first part arranged at the first groove part and a second part arranged at the second groove part.SELECTED DRAWING: Figure 13

Description

The technology disclosed in this specification relates to impact tools.

BACKGROUND ART In the technical field related to impact tools, an impact wrench as disclosed in Patent Document 1 is known.

Japanese Patent No. 6801571

The impact tool has an anvil. When a high load acts on the anvil and the anvil breaks, at least part of the anvil may fall off the impact tool.

An object of the technique disclosed in this specification is to prevent the anvil from coming off.

This specification discloses an impact tool. The impact tool may include a motor, a striking mechanism driven by the motor, an anvil struck by the striking mechanism in a rotational direction, a hammer case housing the striking mechanism, and an anvil bearing. The striking mechanism may be rotatable around an output rotating shaft extending in the front-rear direction. The anvil may have an anvil shaft disposed forward of the striking mechanism, and an anvil projection projecting radially outward from the rear end of the anvil shaft. The anvil protrusion may be struck in a rotational direction about the output rotation axis by the striking mechanism. An anvil bearing may be carried by the hammer case and disposed about the anvil shank. A first groove may be formed in the outer peripheral surface of the anvil shaft so as to surround the output rotating shaft. A second groove may be formed in the inner peripheral surface of the anvil bearing so as to surround the output rotating shaft. The impact tool may comprise a restraining member including a first portion located in the first groove and a second portion located in the second groove.

According to the technology disclosed in this specification, the anvil is prevented from coming off.

FIG. 1 is a perspective view from the left front showing the impact tool according to the embodiment. FIG. 2 is a perspective view from the right rear showing the impact tool according to the embodiment. FIG. 3 is a view of the impact tool according to the embodiment viewed from the right. FIG. 4 is a left side view of the impact tool according to the embodiment. FIG. 5 is a rear view of the impact tool according to the embodiment. FIG. 6 is a front view of the impact tool according to the embodiment. FIG. 7 is a top view of the impact tool according to the embodiment. FIG. 8 is a bottom view of the impact tool according to the embodiment. FIG. 9 is a cross-sectional view showing the impact tool according to the embodiment. FIG. 10 is a cross-sectional view showing the impact tool according to the embodiment. FIG. 11 is a cross-sectional view showing part of the impact tool according to the embodiment. FIG. 12 is a cross-sectional view showing part of the impact tool according to the embodiment. FIG. 13 is a cross-sectional view showing a partially broken state of the anvil shaft according to the embodiment. FIG. 14 is a cross-sectional view showing part of the impact tool according to the embodiment. FIG. 15 is a cross-sectional view showing part of the impact tool according to the embodiment. FIG. 16 is a cross-sectional view showing part of the impact tool according to the embodiment. FIG. 17 is an exploded perspective view showing part of the impact tool according to the embodiment. FIG. 18 is an exploded perspective view showing part of the impact tool according to the embodiment.

In one or more embodiments, an impact tool includes a motor, a striking mechanism driven by the motor, an anvil rotationally struck by the striking mechanism, a hammer case housing the striking mechanism, and an anvil bearing. may be provided. The striking mechanism may be rotatable around an output rotating shaft extending in the front-rear direction. The anvil may have an anvil shaft disposed forward of the striking mechanism, and an anvil projection projecting radially outward from the rear end of the anvil shaft. The anvil protrusion may be struck in a rotational direction about the output rotation axis by the striking mechanism. An anvil bearing may be carried by the hammer case and disposed about the anvil shank. A first groove may be formed in the outer peripheral surface of the anvil shaft so as to surround the output rotating shaft. A second groove may be formed in the inner peripheral surface of the anvil bearing so as to surround the output rotating shaft. The impact tool may comprise a restraining member including a first portion located in the first groove and a second portion located in the second groove.

In the above configuration, the suppressing member including the first portion arranged in the first groove and the second portion arranged in the second groove is provided. portion is caught by the restraining member supported by the second groove portion. Therefore, the anvil shaft is prevented from coming off forward from the hammer case. Therefore, falling off of the anvil from the impact tool is suppressed.

In one or more embodiments, the restraining member may be ring-shaped surrounding the output rotary shaft.

In the above configuration, when at least a portion of the anvil shaft is broken, the anvil shaft can be sufficiently caught by the suppressing member supported by the second groove.

In one or more embodiments, the restraining member may be an O-ring contacting each of the inner surface of the first groove and the inner surface of the second groove.

In the above configuration, the O-ring seals the boundary between the inner surface of the first groove and the inner surface of the second groove. Therefore, for example, grease supplied to the striking mechanism is prevented from leaking from the boundary between the inner surface of the first groove portion and the inner surface of the second groove portion.

In one or more embodiments, the anvil shank may have a breakage origin with a section modulus less than the section modulus of the anvil shank in the first groove. The breakage starting point may be arranged behind the first groove.

In the above configuration, when a high load acts on the anvil shaft, the anvil shaft breaks at the breakage starting point. Since the anvil shaft is broken behind the first groove, the first groove of the anvil shaft can be caught by the suppressing member supported by the second groove.

In one or more embodiments, the impact tool may include a third groove formed in the outer peripheral surface of the anvil shaft to surround the output rotary shaft behind the first groove. The diameter of the anvil shank in the third groove may be smaller than the diameter of the anvil shank in the first groove. The breakage starting portion may include the anvil shaft portion in the third groove portion.

In the above configuration, the breakage starting point is easily formed by forming the third groove.

In one or more embodiments, the inner surface of the first groove includes a first rearwardly facing front side, a first forwardly facing rearward side positioned rearwardly of the first frontal side, and a first frontal side. a radially outwardly facing first peripheral surface connected to each of the radially inner end and the radially inner end of the first rear side surface. The inner surface of the second groove portion may include a rearward facing second front side surface and a radially inward facing second circumferential surface connected to a radially outer end of the second front side surface.

In the above configuration, the first groove portion and the second groove portion are properly formed. Therefore, when the anvil shaft portion is broken at the breakage starting point, the first groove portion of the anvil shaft portion is supported by the second groove portion. It can get caught on the restraining member.

In one or more embodiments, the restraining member may contact each of the first rear side surface and the second front side surface in a condition in which the anvil shank is broken at the breakage origin.

In the above configuration, when the anvil shaft is broken at the breakage starting point, the restraining member supported by the second front side of the second groove catches the first rear side surface of the first groove. It is suppressed to pass forward from.

In one or more embodiments, the hammer case may have a bearing support surface that contacts the forward end of the anvil bearing.

In the above configuration, since the front end portion of the anvil bearing contacts the bearing support surface of the hammer case, the anvil bearing is prevented from slipping forward from the hammer case. Even if the anvil shaft is broken, the anvil bearing does not come off forward from the hammer case, so the suppressing member supported by the second groove of the anvil bearing also does not come off forward from the hammer case. Therefore, when at least a portion of the anvil shaft is broken, the anvil shaft is caught by the restraining member supported in the second groove, thereby restraining the anvil shaft from coming off forward from the hammer case.

In one or more embodiments, the anvil bearing may be a plain bearing.

In the above configuration, the second groove portion is appropriately formed on the inner peripheral surface of the anvil bearing, which is a slide bearing.

Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the embodiments. The constituent elements of the embodiments described below can be combined as appropriate. Also, some components may not be used.

In the embodiments, the terms "left", "right", "front", "rear", "upper", and "lower" are used to describe the positional relationship of each part. These terms refer to relative positions or orientations with respect to the center of the impact tool 1 . The left-right direction, the front-rear direction, and the up-down direction are orthogonal to each other.

[Impact tool]
FIG. 1 is a perspective view from the left front showing an impact tool 1 according to an embodiment. FIG. 2 is a perspective view from the rear right showing the impact tool 1 according to the embodiment. FIG. 3 is a view of the impact tool 1 according to the embodiment viewed from the right. FIG. 4 is a left side view of the impact tool 1 according to the embodiment. FIG. 5 is a rear view of the impact tool 1 according to the embodiment. FIG. 6 is a front view of the impact tool 1 according to the embodiment. FIG. 7 is a top view of the impact tool 1 according to the embodiment. FIG. 8 is a bottom view of the impact tool 1 according to the embodiment. FIG. 9 is a cross-sectional view showing the impact tool 1 according to the embodiment, and corresponds to the cross-sectional view taken along line BB in FIG. FIG. 10 is a cross-sectional view showing the impact tool 1 according to the embodiment, and corresponds to the cross-sectional view taken along line AA of FIG.

In the embodiment, the impact tool 1 is an impact wrench which is a type of fastening tool. The impact tool 1 includes a body housing 2, a grip housing 3, a motor housing 4, a gear case 5, a hammer case 6, a side handle 7, a bumper 8, a battery mounting portion 9, a motor 10, and a controller 11. , a fan 12 , a deceleration mechanism 13 , a spindle 14 , a striking mechanism 15 , an anvil 16 , a trigger switch 17 and a light assembly 18 .

The body housing 2 accommodates the gear case 5 . At least part of the body housing 2 is arranged forward of the grip housing 3 . At least part of the body housing 2 is arranged above the motor housing 4 . The body housing 2 is arranged behind the hammer case 6 . The body housing 2 is connected to the grip housing 3 . The body housing 2 is connected to the motor housing 4 . The body housing 2 is fixed to the hammer case 6 .

The body housing 2 is made of synthetic resin. Nylon resin is exemplified as a synthetic resin forming the body housing 2 . The body housing 2 includes a left body housing 2L and a right body housing 2R arranged to the right of the left body housing 2L. The left body housing 2L and the right body housing 2R constitute a pair of half-split housings. The left body housing 2L and the right body housing 2R are fixed by a plurality of screws 19. As shown in FIG.

The body housing 2 has a body portion 20 and a projecting portion 21 projecting rearward from the body portion 20 . The body portion 20 has a gear case accommodating portion 22 that accommodates the gear case 5 and a motor housing connection portion 23 that is connected to the motor housing 4 . The gear case housing portion 22 has a tubular portion 24 arranged around the gear case 5 and a rear wall portion 25 arranged at the rear end portion of the tubular portion 24 . The motor housing connection portion 23 is arranged to protrude downward from the rear portion of the gear case housing portion 22 . The motor housing connecting portion 23 is arranged behind the motor housing 4 . The protrusion 21 is connected to the grip housing 3 . A portion of the projecting portion 21 projects rearward from the gear case accommodating portion 22 . A portion of the protrusion 21 protrudes rearward from the motor housing connection portion 23 .

The grip housing 3 is gripped by an operator. Grip housing 3 houses controller 11 . Grip housing 3 supports trigger switch 17 . At least part of the grip housing 3 is arranged behind the body housing 2 . The grip housing 3 is connected to the body housing 2 so as to be movable relative to the body housing 2 .

The grip housing 3 is made of synthetic resin. Nylon resin is exemplified as a synthetic resin forming the grip housing 3 . The grip housing 3 includes a left grip housing 3L and a right grip housing 3R arranged to the right of the left grip housing 3L. The left grip housing 3L and the right grip housing 3R form a pair of half-split housings. The left grip housing 3L and right grip housing 3R are fixed by a plurality of screws 26. As shown in FIG.

The grip housing 3 is connected to a grip portion 27 gripped by an operator, a controller accommodating portion 28 accommodating the controller 11, a battery connecting portion 29 in which the battery mounting portion 9 is arranged, and the protruding portion 21 of the main body housing 2. It has a connection part 30 that connects. The grip portion 27 includes a rear grip portion 31 extending upward from the rear portion of the controller housing portion 28 , an upper grip portion 32 extending forward from the upper end portion of the rear grip portion 31 , and a front grip portion 32 extending downward from the front end portion of the upper grip portion 32 . and a grip portion 33 . The front grip portion 33 is arranged to connect the front end portion of the upper grip portion 32 and the upper portion of the connecting portion 30 . The grip portion 27 is formed in a substantially annular shape. The trigger switch 17 is arranged above the rear grip portion 31 . The battery connector 29 is arranged below the controller housing 28 . At least part of the battery connector 29 is arranged forward of the controller housing 28 . The connecting portion 30 is arranged in the front portion of the controller accommodating portion 28 .

Motor housing 4 accommodates motor 10 . The motor housing 4 is arranged below the gear case 5 . A motor housing 4 is connected to the body housing 2 . A motor housing 4 is fixed to the gear case 5 .

The motor housing 4 is made of synthetic resin. A polycarbonate resin is exemplified as a synthetic resin forming the motor housing 4 .

The motor housing 4 has a tubular portion 34 arranged around the motor 10 and a lower wall portion 35 arranged at the lower end portion of the tubular portion 34 .

An opening 36 is provided in the upper portion of the motor housing 4 . An opening 37 is formed in the lower portion of the gear case accommodating portion 22 .

An opening 38 is provided in the rear of the motor housing 4 . An opening 39 is provided in the motor housing connection 23 . An opening 40A is provided in the rear portion of the body housing 2 . An opening 40B is provided in the front portion of the grip housing 3 . The internal space of the motor housing 4 and the internal space of the controller accommodating portion 28 are connected via the openings 38, 39, 40A, and 40B.

The gear case 5 accommodates at least part of the speed reduction mechanism 13 . The gear case 5 is arranged behind the hammer case 6 . Gear case 5 is fixed to hammer case 6 .

The gear case 5 is made of metal. Aluminum or magnesium is exemplified as the metal forming the gear case 5 .

The gear case 5 is substantially cylindrical. An opening 41 is provided in the front portion of the gear case 5 . An opening 42 is provided in the rear portion of the gear case 5 . An opening 43 is provided in the lower portion of the gear case 5 . A bearing cover 44 is arranged in the opening 42 of the gear case 5 . The bearing cover 44 is fixed to the rear portion of the gear case 5 with screws 45 .

Hammer case 6 accommodates striking mechanism 15 . A hammer case 6 is connected to the front portion of the main body housing 2 . The hammer case 6 is connected to the front portion of the gear case 5 .

The hammer case 6 is made of metal. Aluminum is exemplified as the metal forming the hammer case 6 .

Hammer case 6 is substantially cylindrical. The hammer case 6 has a first tubular portion 46 and a second tubular portion 47 . The first cylindrical portion 46 is arranged around the striking mechanism 15 . The second tubular portion 47 is arranged forward of the first tubular portion 46 . The outer diameter of the second cylindrical portion 47 is smaller than the outer diameter of the first cylindrical portion 46 . An opening 48 is provided in the rear portion of the first tubular portion 46 . An opening 49 is provided in the front portion of the second tubular portion 47 . A front end of the gear case 5 is inserted into the opening 48 .

Gear case 5 and hammer case 6 are fixed by a plurality of screws 50 . Gear case 5 has a plurality of screw bosses 51 . At least part of the body housing 2 is arranged to cover the screw boss 51 . The body housing 2 is also fixed to the hammer case 6 with a plurality of screws 50. As shown in FIG. Hammer case 6 has a plurality of screw bosses 52 . A screw 50 is inserted into a through hole provided in the body housing 2 and a through hole provided in a screw boss 51 of the gear case 5 . The screw 50 is inserted into a threaded hole provided in a threaded boss 52 of the hammer case 6 . The screw 50 is inserted into the through hole of the main body housing 2 and the through hole of the screw boss 51 from behind the screw boss 51 and then into the screw hole of the screw boss 52 .

Motor housing 4 and gear case 5 are fixed by a plurality of screws 53 . The motor housing 4 has multiple screw bosses 54 . A screw 53 is inserted into a through hole provided in a screw boss 54 of the motor housing 4 . The screw 53 is inserted into a threaded hole provided at the bottom of the gear case 5 . The screw 53 is inserted into the through hole of the screw boss 54 from below and then into the screw hole of the gear case 5 .

The internal space of the motor housing 4 and the internal space of the gear case 5 are connected via the openings 36 and 43 .

The internal space of the gear case 5 and the internal space of the hammer case 6 are connected via the openings 41 and 48 .

The side handle 7 is held by the operator. The side handle 7 has a handle portion 55 gripped by the operator and a base portion 56 fixed to the hammer case 6 . The handle portion 55 is arranged on the left side of the hammer case 6 . The base portion 56 includes a first base portion 57 and a second base portion 58 arranged below the first base portion 57 . Each of the first base portion 57 and the second base portion 58 has an arc shape. The first base portion 57 and the second base portion 58 are arranged so as to sandwich the first tubular portion 46 of the hammer case 6 . A cover 460 is arranged on the upper portion of the first tubular portion 46 . At least part of the first base portion 57 overlaps the cover 460 . A right end portion of the first base portion 57 and a right end portion of the second base portion 58 are connected via a hinge 59 . A left end portion of the first base portion 57 and a left end portion of the second base portion 58 are each connected to the handle portion 55 . A left end portion of the first base portion 57 and a left end portion of the second base portion 58 are connected via a tightening mechanism 60 . The tightening mechanism 60 has a screw 61 arranged in a screw hole provided at the left end of the second base portion 58 and a dial portion 62 rotatable with respect to the screw 61 . The operator can operate the dial portion 62 to rotate the dial portion 62 . The distance between the left end of the first base portion 57 and the left end of the second base portion 58 is adjusted by rotating the dial portion 62 . By rotating the screw 61 so that the distance between the left end of the first base portion 57 and the left end of the second base portion 58 is shortened, the hammer case 6 is tightened to the base portion 56, and the side handle 7 is attached to the hammer. It is fixed to the case 6.

Although the handle portion 55 is arranged on the left side of the hammer case 6 in the embodiment, the handle portion 55 can be arranged at any position around the hammer case 6 . For example, the handle portion 55 can be arranged on the left side of the hammer case 6 , can be arranged above the hammer case 6 , and can be arranged below the hammer case 6 . The position (angle) of the handle portion 55 with respect to the hammer case 6 can be adjusted 360 degrees.

The bumper 8 is arranged to cover at least part of the surface of the hammer case 6 . In the embodiment, the bumper 8 is arranged to cover the surface of the first tubular portion 46 . A bumper 8 protects the hammer case 6 . The bumper 8 suppresses contact between the hammer case 6 and the impact tool 1 and surrounding objects. The bumper 8 is made of an elastic material that is softer than the hammer case 6 . Styrene-butadiene rubber is exemplified as an elastic body forming the bumper 8 .

The battery mounting portion 9 is provided in the battery connecting portion 29 . A battery pack 63 is attached to the battery attachment portion 9 . A portion of the battery connecting portion 29 is arranged above the battery pack 63 attached to the battery attaching portion 9 . A portion of the battery connecting portion 29 is arranged forward of the battery pack 63 attached to the battery attaching portion 9 . A battery pack 63 functions as a power source for the impact tool 1 . The battery pack 63 is attachable to and detachable from the battery mounting portion 9 . Battery pack 63 includes a secondary battery. In embodiments, the battery pack 63 includes rechargeable lithium-ion batteries. By being attached to the battery attachment portion 9 , the battery pack 63 can supply electric power to the impact tool 1 . Motor 10 is driven based on power supplied from battery pack 63 . The controller 11 operates based on power supplied from the battery pack 63 .

The battery mounting portion 9 includes a plate-shaped terminal 64 . The terminal 64 has a synthetic resin plate and a metal connection terminal arranged on the plate. By attaching the battery pack 63 to the battery attachment portion 9, the connection terminals of the battery pack 63 and the connection terminals of the terminal 64 are connected. Terminals 64 are held by terminal holders 65 . The terminal holder 65 is sandwiched between the left grip housing 3L and the right grip housing 3R. A spring 66 and a buffer member 67 are arranged in a portion of the battery connecting portion 29 arranged in front of the battery pack 63 . A spring 66 is arranged in front of the terminal holder 65 . The spring 66 is supported by a portion of the battery connecting portion 29 arranged forward of the terminal 64 . A spring 66 biases the terminal holder 65 rearward. The buffer member 67 is arranged in front of the battery pack 63 attached to the battery attachment portion 9 . The cushioning member 67 is supported by a part of the battery connecting portion 29 arranged forward of the battery pack 63 mounted on the battery mounting portion 9 . Rubber is exemplified as the buffer member 67 . The buffer member 67 contacts the front portion of the battery pack 63 . For example, when the impact tool 1 is dropped, the elastic force of the spring 66 reduces the impact acting on the terminal 64 , and the cushioning member 67 reduces the impact acting on the battery pack 63 .

A motor 10 functions as a power source for the impact tool 1 . The motor 10 is an inner rotor type brushless motor. Motor 10 has a stator 68 , a rotor 69 and a rotor shaft 70 . Stator 68 is supported by motor housing 4 . At least part of the rotor 69 is arranged inside the stator 68 . A rotor shaft 70 is fixed to the rotor 69 . The rotor 69 is rotatable with respect to the stator 68 around a vertically extending motor rotation axis MX.

The stator 68 has a stator core 71 , insulators 72 and coils 73 .

The stator core 71 is arranged radially outside the rotor 69 . Stator core 71 includes a plurality of laminated steel plates. A steel plate is a metal plate whose main component is iron. The stator core 71 has a cylindrical yoke and a plurality of teeth protruding radially inward of the yoke from the inner peripheral surface of the yoke.

The insulator 72 is an electrical insulating member made of synthetic resin. At least part of insulator 72 is provided above stator core 71 . At least part of insulator 72 is provided below stator core 71 . At least part of insulator 72 is arranged to cover the surfaces of the teeth of stator core 71 .

Coils 73 are attached to the teeth of stator core 71 via insulators 72 . Stator core 71 and coil 73 are electrically insulated by insulator 72 . A plurality of coils 73 are connected via a busbar unit 74 .

The rotor 69 rotates around the motor rotation axis MX. The rotor 69 has a rotor core 75 and rotor magnets 76 .

Rotor core 75 includes a plurality of laminated steel plates. The rotor core 75 is tubular.

A rotor magnet 76 is fixed to the rotor core 75 . In embodiments, the rotor magnets 76 are located inside the rotor core 75 .

A sensor substrate 77 is fixed to the insulator 72 . The sensor board 77 detects the rotational position of the rotor 69 . The sensor board 77 has an annular circuit board and a rotation detecting element supported by the circuit board. At least part of the sensor substrate 77 faces the rotor magnet 76 . The rotation detection element detects the position of the rotor 69 in the rotational direction by detecting the position of the rotor magnet 76 .

The rotor shaft 70 is arranged inside the rotor core 75 . Rotor shaft 70 is fixed to rotor core 75 . The rotor 69 and rotor shaft 70 rotate together about the motor rotation axis MX. The upper end of rotor shaft 70 protrudes upward from the upper end surface of rotor core 75 . A lower end portion of the rotor shaft 70 protrudes downward from a lower end surface of the rotor core 75 .

The rotor shaft 70 is rotatably supported by a rotor bearing 78 and a rotor bearing 79, respectively. The rotor bearing 78 rotatably supports the upper portion of the rotor shaft 70 arranged above the upper end surface of the rotor core 75 . Rotor bearing 79 rotatably supports the lower portion of rotor shaft 70 arranged below the lower end surface of rotor core 75 . The rotor bearing 78 is held by the gear case 5 . A rotor bearing 79 is held in the motor housing 4 .

A first bevel gear 80 is fixed to the upper end of the rotor shaft 70 . The first bevel gear 80 is connected to at least part of the speed reduction mechanism 13 . The rotor shaft 70 is connected to the speed reduction mechanism 13 via a first bevel gear 80 .

The controller 11 outputs control signals for controlling the motor 10 . Controller 11 includes a circuit board on which a plurality of electronic components are mounted. Electronic components mounted on a circuit board include processors such as CPUs (Central Processing Units), non-volatile memories such as ROMs (Read Only Memory) or storage, volatile memories such as RAMs (Random Access Memory), electric field Field Effect Transistors (FETs) and resistors are exemplified.

The controller 11 is housed in the controller housing portion 28 of the grip housing 3 . The controller 11 is held by the controller case 81 in the controller housing portion 28 .

Fan 12 generates airflow for cooling motor 10 and controller 11 . The fan 12 is arranged above the stator 68 of the motor 10 . Fan 12 is fixed to the upper portion of rotor shaft 70 . Fan 12 is arranged between rotor bearing 78 and stator core 71 . Fan 12 and rotor shaft 70 rotate together. An intake port 82 is provided in the lower wall portion 35 of the motor housing 4 . An exhaust port 83 is provided in each of the upper front, left, and right portions of the cylindrical portion 34 of the motor housing 4 . Air inlets 84 are provided in each of the left and right portions of the controller housing portion 28 . As the fan 12 rotates, the air in the outer space of the motor housing 4 flows into the inner space of the motor housing 4 through the intake port 82 . The air that has flowed into the internal space of the motor housing 4 cools the motor 10 by circulating through the internal space of the motor housing 4 . At least part of the air that has flowed through the internal space of the motor housing 4 flows out to the external space of the motor housing 4 through the exhaust port 83 as the fan 12 rotates. In addition, the rotation of the fan 12 causes the air in the outer space of the grip housing 3 to flow into the inner space of the controller accommodating portion 28 through the air inlet 84 . The air that has flowed into the internal space of the controller accommodating portion 28 cools the controller 11 by circulating through the internal space of the controller accommodating portion 28 . The air that has flowed through the internal space of the controller accommodating portion 28 flows out to the external space of the motor housing 4 through the exhaust port 83 as the fan 12 rotates.

In an embodiment, a baffle plate 85 is positioned between fan 12 and stator 68 . The baffle plate 85 guides the air that is circulated by the rotation of the fan 12 .

The speed reduction mechanism 13 transmits the rotational force of the motor 10 to the impact mechanism 15 via the spindle 14 . The speed reduction mechanism 13 connects the rotor shaft 70 and the spindle 14 . The reduction mechanism 13 rotates the spindle 14 at a rotational speed lower than that of the rotor shaft 70 .

The speed reduction mechanism 13 has a second bevel gear 86 meshing with the first bevel gear 80 and a planetary gear mechanism 87 driven by the torque of the motor 10 transmitted via the second bevel gear 86 .

The planetary gear mechanism 87 has a sun gear 88 , a plurality of planetary gears 89 arranged around the sun gear 88 , and an internal gear 90 arranged around the plurality of planetary gears 89 . The planetary gear mechanism 87 is housed in the gear case 5 .

A second bevel gear 86 is arranged around the sun gear 88 . A second bevel gear 86 is fixed to the sun gear 88 . The second bevel gear 86 and the sun gear 88 rotate together. The second bevel gear 86 and the sun gear 88 are rotatable around an output rotation axis BX extending in the front-rear direction. The output rotation axis BX and the motor rotation axis MX are orthogonal. A rear end portion of the sun gear 88 is supported by a gear bearing 91 . An intermediate portion of the sun gear 88 is supported by a gear bearing 92 . The gear bearing 91 is held by the bearing cover 44 . The gear bearing 92 is held by the gear case 5 . As the rotor shaft 70 rotates and the first bevel gear 80 rotates, the second bevel gear 86 rotates. The rotation of the second bevel gear 86 causes the sun gear 88 to rotate.

Each of the planetary gears 89 meshes with the sun gear 88 . Planetary gear 89 is rotatably supported by spindle 14 via pin 93 . Spindle 14 is rotated by planetary gear 89 . The internal gear 90 has internal teeth that mesh with the planetary gear 89 . The internal gear 90 is fixed to the gear case 5 . A plurality of protrusions are provided on the outer peripheral surface of the internal gear 90 . A convex portion of the internal gear 90 fits into a concave portion provided on the inner peripheral surface of the gear case 5 . The internal gear 90 is always non-rotatable with respect to the gear case 5 .

When the rotor shaft 70 and the first bevel gear 80 are rotated by driving the motor 10, the second bevel gear 86 and the sun gear 88 are rotated. When the sun gear 88 rotates, the planetary gears 89 revolve around the sun gear 88 . The planetary gear 89 revolves while meshing with the inner teeth of the internal gear 90 . The revolution of planetary gear 89 causes spindle 14 , which is connected to planetary gear 89 via pin 93 , to rotate at a rotational speed lower than that of rotor shaft 70 .

The spindle 14 is rotated by the rotational force of the motor 10 transmitted by the speed reduction mechanism 13 . The spindle 14 transmits the rotational force of the motor 10 transmitted via the reduction mechanism 13 to the impact mechanism 15 . The spindle 14 is rotatable around the output rotation axis BX. A rear portion of the spindle 14 is housed in the gear case 5 . A front portion of the spindle 14 is housed in the hammer case 6 . At least part of the spindle 14 is arranged in front of the speed reduction mechanism 13 . Spindle 14 is positioned behind anvil 16 .

The spindle 14 has a flange portion 94 , a spindle shaft portion 95 projecting forward from the flange portion 94 , and a projecting portion 96 projecting rearward from the flange portion 94 . Planetary gear 89 is rotatably supported by flange portion 94 and projecting portion 96 via pin 93 . The spindle 14 is rotatably supported by a spindle bearing 97 . A spindle bearing 97 rotatably supports the protrusion 96 . The spindle bearing 97 is held by the gear case 5 .

The striking mechanism 15 strikes the anvil 16 in a rotational direction around the output rotation axis BX. The striking mechanism 15 is driven by the motor 10 . The impact mechanism 15 is rotatable around the output rotation axis BX. The rotational force of the motor 10 is transmitted to the striking mechanism 15 via the speed reduction mechanism 13 and the spindle 14 . The striking mechanism 15 strikes the anvil 16 in the rotational direction based on the rotational force of the spindle 14 rotated by the motor 10 .

The striking mechanism 15 is housed in the first tubular portion 46 of the hammer case 6 . The striking mechanism 15 has a hammer 98 , a ball 99 , a first coil spring 100 , a second coil spring 101 , a third coil spring 102 , a first washer 103 and a second washer 104 .

The hammer 98 is arranged forward of the speed reduction mechanism 13 . A hammer 98 is arranged around the spindle 14 . A hammer 98 is retained on the spindle 14 . Ball 99 is positioned between spindle 14 and hammer 98 . The hammer 98 has a tubular hammer body 105 and a hammer protrusion 106 provided on the front portion of the hammer body 105 . An annular recess 107 is provided in the rear surface of the hammer body 105 . The recess 107 is recessed forward from the rear surface of the hammer body 105 .

A hammer 98 is arranged around the spindle shaft portion 95 . Hammer 98 has a hole 108 in which spindle shank 95 is arranged.

Hammer 98 is rotated by motor 10 . The rotational force of the motor 10 is transmitted to the hammer 98 via the speed reduction mechanism 13 and the spindle 14 . Hammer 98 is rotatable together with spindle 14 based on the rotational force of spindle 14 rotated by motor 10 . Each of the hammer 98 and the spindle 14 rotates around the output rotation axis BX.

The first washer 103 is arranged inside the recess 107 . The first washer 103 is supported by the hammer 98 via multiple balls 109 . The ball 109 is arranged forward of the first washer 103 .

The second washer 104 is arranged behind the first washer 103 inside the recess 107 . The outer diameter of second washer 104 is smaller than the outer diameter of first washer 103 . The second washer 104 and the hammer 98 are relatively movable in the front-rear direction.

The first coil spring 100 is arranged around the spindle shaft portion 95 . A rear end portion of the first coil spring 100 is supported by the flange portion 94 . A front end portion of the first coil spring 100 is arranged inside the recess 107 and supported by the first washer 103 . The first coil spring 100 always generates an elastic force that moves the hammer 98 forward.

A second coil spring 101 is arranged around the spindle shaft portion 95 . The second coil spring 101 is arranged radially inside the first coil spring 100 . A rear end portion of the second coil spring 101 is supported by the flange portion 94 . The front end of the second coil spring 101 is arranged inside the recess 107 and supported by the second washer 104 . The second coil spring 101 generates an elastic force that moves the hammer 98 forward when the hammer 98 moves backward.

A third coil spring 102 is arranged around the spindle shaft portion 95 . The third coil spring 102 is arranged radially inside the first coil spring 100 . The third coil spring 102 is arranged inside the recess 107 . A rear end portion of the third coil spring 102 is supported by a second washer 104 . A front end portion of the third coil spring 102 is supported by the first washer 103 . The third coil spring 102 generates an elastic force that moves the second coil spring 101 rearward. The elastic force of the third coil spring 102 presses the rear end of the second coil spring 101 against the flange portion 94 . As a result, the second coil spring 101 is prevented from moving loosely with respect to the flange portion 94 .

Ball 99 is made of metal such as steel. A ball 99 is arranged between the spindle shaft portion 95 and the hammer 98 . The spindle 14 has a spindle groove 110 in which at least a portion of the balls 99 are arranged. The spindle groove 110 is provided on a portion of the outer surface of the spindle shaft portion 95 . Hammer 98 has a hammer groove 111 in which at least a portion of ball 99 is arranged. A hammer groove 111 is provided in a portion of the inner surface of the hammer 98 . Ball 99 is positioned between spindle groove 110 and hammer groove 111 . The ball 99 can roll inside the spindle groove 110 and inside the hammer groove 111 respectively. Hammer 98 is movable with ball 99 . The spindle 14 and the hammer 98 can relatively move in a direction parallel to the output rotation axis BX and in a direction of rotation about the output rotation axis BX within a movable range defined by the spindle groove 110 and the hammer groove 111. can.

The anvil 16 is the output part of the impact tool 1 that rotates based on the torque of the motor 10 . At least part of the anvil 16 is arranged forward of the hammer 98 .

Anvil 16 has an anvil recess 112 . Anvil recess 112 is provided at the rear end of anvil 16 . Anvil recess 112 is recessed forward from the rear end of anvil 16 . A spindle 14 is positioned behind the anvil 16 . A front end of the spindle shaft portion 95 is located in the anvil recess 112 .

Anvil 16 has anvil shaft 113 and anvil projection 114 . The anvil shaft portion 113 is arranged forward of the striking mechanism 15 . The anvil projection 114 protrudes radially outward of the anvil shaft 113 from the rear end of the anvil shaft 113 . The anvil projection 114 is struck by the striking mechanism 15 in the direction of rotation about the output rotation axis BX.

A front end portion of the anvil shaft portion 113 is arranged forward of the hammer case 6 through the opening 49 . A socket is attached to the front end portion of the anvil shaft portion 113 as a tip tool.

Anvil 16 is rotatably supported by anvil bearing 115 . Anvil bearing 115 is arranged around anvil shaft 113 . The anvil 16 is rotatable around the output rotation axis BX. Anvil bearing 115 is held by hammer case 6 . The anvil bearing 115 is arranged inside the second tubular portion 47 of the hammer case 6 . The anvil bearing 115 is held by the second tubular portion 47 of the hammer case 6 .

A trigger switch 17 is operated by an operator to drive the motor 10 . Driving the motor 10 means that the coil 73 of the stator 68 is energized to rotate the rotor 69 . The trigger switch 17 is provided above the rear grip portion 31 . Trigger switch 17 includes trigger lever 116 and switch body 117 . The switch body 117 is arranged in the internal space of the rear grip portion 31 . The trigger lever 116 protrudes forward from the upper front portion of the rear grip portion 31 . The trigger lever 116 is operated by the operator so as to move backward. The motor 10 is driven by operating the trigger lever 116 to move backward. By releasing the operation of the trigger lever 116, the driving of the motor 10 is stopped.

The light assembly 18 emits illumination light. The light assembly 18 illuminates the anvil 16 and the periphery of the anvil 16 with illumination light. The light assembly 18 illuminates the front of the anvil 16 with illumination light. Also, the light assembly 18 illuminates the socket attached to the anvil 16 and the periphery of the socket with illumination light. In the embodiment, the light assembly 18 has a circuit board 118 , a light emitting element 119 mounted on the front surface of the circuit board 118 , and a ring-shaped light cover 120 arranged forward of the circuit board 118 . Light cover 120 is arranged to cover light emitting element 119 . The light assembly 18 is arranged around the second tubular portion 47 of the hammer case 6 . A ring spring 181 is arranged in front of the light assembly 18 to prevent the light assembly 18 from slipping forward from the second tubular portion 47 .

[Suppression member]
FIG. 11 is a cross-sectional view showing part of the impact tool 1 according to the embodiment, and corresponds to an enlarged view of part of FIG. FIG. 12 is a cross-sectional view showing part of the impact tool 1 according to the embodiment, and corresponds to an enlarged view of part of FIG.

11 and 12, the direction parallel to the output rotation axis BX will be referred to as the axial direction, and the direction that revolves around the output rotation axis BX will be referred to as the circumferential direction or the rotation direction. is appropriately referred to as the radial direction. Further, in the radial direction, a position close to or approaching the output rotation axis BX is appropriately referred to as radial inner side, and a position far from or away from the output rotation axis BX is appropriately referred to as radial outer side.

In a cross section perpendicular to the output rotation axis BX, the shape of the outer peripheral surface of the anvil shaft portion 113 is circular. The shape of the inner peripheral surface of the anvil bearing 115 is circular in a cross section perpendicular to the output rotation axis BX.

As shown in FIGS. 11 and 12 , a first groove portion 121 is formed on the outer peripheral surface of the anvil shaft portion 113 . The first groove portion 121 is formed on the outer peripheral surface of the anvil shaft portion 113 so as to surround the output rotating shaft BX.

A second groove portion 122 is formed on the inner peripheral surface of the anvil bearing 115 . The second groove portion 122 is formed on the inner peripheral surface of the anvil bearing 115 so as to surround the output rotating shaft BX.

In embodiments, the anvil bearing 115 is a plain bearing. The second groove portion 122 is formed on the inner peripheral surface of the slide bearing. Anvil bearing 115 is cylindrical. In embodiments, a sleeve is used as the anvil bearing 115 . The slide bearing may be formed by impregnating a cylindrical porous metal body manufactured by powder metallurgy, for example, with lubricating oil.

The impact tool 1 includes a restraining member 123 that restrains the anvil shaft portion 113 from slipping forward from the hammer case 6 . Suppression member 123 includes a first portion 124 arranged in first groove portion 121 and a second portion 125 arranged in second groove portion 122 . The first portion 124 is a portion of the radially inner restraining member 123 . The second portion 125 is a portion of the restraining member 123 radially outward of the first portion 124 .

The suppressing member 123 has a ring shape surrounding the output rotation axis BX. In the embodiment, the suppressing member 123 is an O-ring that contacts the inner surface of the first groove portion 121 and the inner surface of the second groove portion 122, respectively.

The inner surface of first groove portion 121 includes a first front side surface 126 , a first rear side surface 127 and a first peripheral surface 128 . The first front side 126 faces rearward. The first rear side surface 127 is arranged behind the first front side surface 126 . The first rear side 127 faces forward. The first peripheral surface 128 is connected to the radially inner end of the first front side 126 and the radially inner end of the first rear side 127 respectively. The first peripheral surface 128 faces radially outward.

The inner surface of the second groove portion 122 includes a second front side surface 129 , a second rear side surface 130 and a second peripheral surface 131 . The second front side 129 faces rearward. The second rear side surface 130 is arranged rearward of the second front side surface 129 . The second rear side 130 faces forward. The second peripheral surface 131 is connected to the radially outer end of the second front side surface 129 and the radially outer end of the second rear side surface 130 . The second peripheral surface 131 faces radially inward.

In embodiments, the depth of the first groove 121 and the depth of the second groove 122 are substantially equal. In addition, the depth of the first groove portion 121 may be deeper than the depth of the second groove portion 122 , and the depth of the second groove portion 122 may be deeper than the depth of the first groove portion 121 . The depth of the first groove portion 121 refers to the dimension of the first groove portion 121 in the radial direction. That is, the depth of the first groove portion 121 refers to the distance between the outer peripheral surface of the anvil shaft portion 113 and the first peripheral surface 128 in the radial direction. The depth of the second groove portion 122 refers to the dimension of the second groove portion 122 in the radial direction. That is, the depth of the second groove portion 122 refers to the distance between the inner peripheral surface of the anvil bearing 115 and the second peripheral surface 131 in the radial direction.

The dimension of the first groove portion 121 in the axial direction is shorter than the dimension of the second groove portion 122 in the axial direction. The dimension of the first groove portion 121 in the axial direction refers to the distance between the first front side surface 126 and the first rear side surface 127 . The dimension of the second groove portion 122 in the axial direction refers to the distance between the second front side surface 129 and the second rear side surface 130 . In the example shown in Figures 11 and 12, the axial positions of the first front side 126 and the second front side 129 are substantially equal. The first rear side surface 127 is arranged forward of the second rear side surface 130 .

Note that the position of the first front side surface 126 and the position of the second front side surface 129 in the axial direction may be different. The first rear side surface 127 may not be positioned forward of the second rear side surface 130 or may be positioned rearward of the second rear side surface 130 .

The suppressing member 123 is arranged so as to contact each of the first peripheral surface 128 and the second peripheral surface 131 . As noted above, in embodiments, the restraining member 123 is an O-ring. The suppressing member 123 is slightly crushed by the first peripheral surface 128 and the second peripheral surface 131 . The suppressing member 123 seals the boundary between the first peripheral surface 128 and the second peripheral surface 131 .

In the example shown in FIGS. 11 and 12, the restraining member 123 is arranged to contact the first front side surface 126 and the second front side surface 129, respectively. The suppressing member 123 seals the boundary between the anvil shaft portion 113 and the anvil bearing 115 .

The hammer case 6 has a bearing support surface 132 that contacts the front end of the anvil bearing 115 . The bearing support surface 132 is provided at the front end portion of the second tubular portion 47 . The bearing support surface 132 faces rearward. The bearing support surface 132 presses the anvil bearing 115 from the front. The bearing support surface 132 prevents the anvil bearing 115 from slipping forward from the hammer case 6 . The bearing support surface 132 is ring-shaped in a plane orthogonal to the output rotation axis BX. The opening 49 is defined radially inward of the bearing support surface 132 .

A front end portion of the anvil shaft portion 113 is arranged forward of the second cylindrical portion 47 through the opening 49 . At least a portion of anvil shank 113 is disposed inside opening 49 . A seal member 133 is provided at the front end portion of the second tubular portion 47 . The seal member 133 is arranged inside the opening 49 . The seal member 133 seals the boundary between the front end portion of the second tubular portion 47 and the anvil shaft portion 113 . The sealing member 133 is arranged forward of the suppressing member 123 .

The anvil shaft portion 113 has a breakage starting point portion 134 arranged behind the first groove portion 121 . The section modulus of anvil shaft portion 113 at breakage starting point 134 is smaller than the section modulus of anvil shaft portion 113 at first groove portion 121 . That is, the section modulus of the anvil shaft portion 113 passing through the breakage starting point 134 and perpendicular to the output rotation axis BX is smaller than the section modulus of the anvil shaft portion 113 passing through the first groove portion 121 and perpendicular to the output rotation axis BX. In the anvil shaft portion 113, the breakage starting portion 134 is the portion having the lowest strength against bending moment. That is, in the anvil shaft portion 113, the breakage starting portion 134 is the portion that is most likely to break when a high load acts on the anvil shaft portion 113. As shown in FIG.

A third groove portion 135 is formed on the outer peripheral surface of the anvil shaft portion 113 . The third groove portion 135 is formed behind the first groove portion 121 . The third groove portion 135 is formed on the outer peripheral surface of the anvil shaft portion 113 so as to surround the output rotating shaft BX.

The depth of the third groove portion 135 is deeper than the depth of the first groove portion 121 . The depth of the third groove portion 135 refers to the dimension of the third groove portion 135 in the radial direction. Diameter Db of anvil shaft portion 113 in third groove portion 135 is smaller than diameter Da of anvil shaft portion 113 in first groove portion 121 . Breakage starting portion 134 includes anvil shaft portion 113 in third groove portion 135 . A large-diameter portion 136 of the anvil shaft portion 113 having a diameter larger than the diameters Da and Db is provided between the first groove portion 121 and the third groove portion 135 in the axial direction. A first rear side surface 127 is arranged in front of the large diameter portion 136 .

FIG. 13 is a cross-sectional view showing a partially broken state of the anvil shaft portion 113 according to the embodiment. For example, if a high load acts on the anvil shaft portion 113 during fastening work, at least a portion of the anvil shaft portion 113 may break. In the embodiment, the anvil shaft portion 113 is provided with a breakage starting portion 134 . Therefore, when a high load acts on the anvil shaft portion 113, the anvil shaft portion 113 breaks at the breakage starting point 134 as shown in FIG.

When the anvil shaft portion 113 is broken at the breakage starting point 134 , the anvil shaft portion 113 ahead of the breakage starting point 134 may move forward with respect to the hammer case 6 . When the anvil shaft portion 113 moves forward, the first rear side surface 127 of the first groove portion 121 is caught by the suppressing member 123 .

A front end of the anvil bearing 115 contacts the bearing support surface 132 of the hammer case 6 . Even if the anvil shaft portion 113 breaks, the anvil bearing 115 does not move forward with respect to the hammer case 6 . The suppressing member 123 is supported by the second front side surface 129 of the second groove portion 122 . The suppressing member 123 supported by the second front side surface 129 of the anvil bearing 115 also does not move forward with respect to the hammer case 6 . As shown in FIG. 13 , when anvil shaft portion 113 is broken at breakage starting point 134 , restraining member 123 contacts first rear side surface 127 and second front side surface 129 . The anvil shaft portion 113 is caught by the suppressing member 123 that does not move forward with respect to the hammer case 6 . Therefore, when the anvil shaft portion 113 is broken at the breakage starting point 134 , the anvil shaft portion 113 is prevented from slipping forward from the hammer case 6 . That is, when the anvil shaft portion 113 is broken, the anvil shaft portion 113 ahead of the breakage starting portion 134 is prevented from coming off the impact tool 1 .

[Anti-vibration mechanism]
FIG. 14 is a cross-sectional view showing part of the impact tool 1 according to the embodiment, and corresponds to the cross-sectional view taken along line CC of FIG. FIG. 15 is a cross-sectional view showing part of the impact tool 1 according to the embodiment, and corresponds to the cross-sectional view taken along line DD of FIG. FIG. 16 is a cross-sectional view showing part of the impact tool 1 according to the embodiment, and corresponds to a view of the E′-E′ line cross-section of FIG. 14 viewed from above (direction E). FIG. 17 is an exploded perspective view showing part of the impact tool 1 according to the embodiment. FIG. 18 is an exploded perspective view showing part of the impact tool 1 according to the embodiment.

As shown in FIGS. 14, 15, 16, 17 and 18, the impact tool 1 has a vibration isolation mechanism 137. As shown in FIG. The vibration isolation mechanism 137 suppresses transmission of vibration of the hammer case 6 to the grip housing 3 via the body housing 2 . Vibration may occur in the hammer case 6 due to at least one of the rotation of the anvil 16 during the fastening work, the impact of the anvil 16 by the impact mechanism 15, and the load received by the anvil 16 from the work target. When the vibration of the hammer case 6 is transmitted to the grip housing 3 through the main body housing 2 and the grip housing 3 is shaken, the workability of the fastening work is lowered and the operator holding the grip housing 3 feels uncomfortable. there's a possibility that. The transmission of the vibration of the hammer case 6 to the grip housing 3 via the main body housing 2 is suppressed by the vibration isolation mechanism 137, thereby reducing the workability of the fastening work and causing inconvenience to the operator holding the grip housing 3. Giving pleasure is suppressed. Also, in the embodiment, the controller 11 is housed in the controller housing portion 28 of the grip housing 3 . When the controller 11 vibrates, malfunction of the controller 11 may occur. The transmission of the vibration of the hammer case 6 to the grip housing 3 is suppressed by the vibration isolation mechanism 137, thereby suppressing the controller 11 from vibrating.

The anti-vibration mechanism 137 includes an anti-vibration member 138 and an anti-vibration member 139 arranged between the body housing 2 and the grip housing 3 . Each of the vibration isolating member 138 and the vibration isolating member 139 suppresses transmission of vibration of the hammer case 6 to the grip housing 3 via the body housing 2 .

As described above, the body housing 2 has the body portion 20 and the projecting portion 21 projecting rearward from the body portion 20 . The grip housing 3 has a connecting portion 30 connected to the protrusion 21 . Each of the vibration isolating member 138 and the vibration isolating member 139 is arranged between the projecting portion 21 and the connecting portion 30 .

In addition, as shown in FIGS. 14 and 15 , the left main body housing 2L and the right main body housing 2R are fixed by screws 190 at the projecting portion 21 .

The vibration isolation member 138 is a first vibration isolation member that suppresses transmission of vibration of the hammer case 6 in the axial direction parallel to the output rotation axis BX to the grip housing 3 via the body housing 2 . Anti-vibration member 138 contains rubber. In embodiments, the vibration isolation member 138 is cushion rubber.

The anti-vibration member 139 is a second anti-vibration member that suppresses transmission of vibration of the hammer case 6 in the direction of rotation about the output rotation axis BX to the grip housing 3 via the body housing 2 . Anti-vibration member 139 includes a spring. In embodiments, the vibration isolation member 139 is a compression spring.

As shown in FIGS. 17 and 18, the outer shape of the protrusion 21 is substantially cylindrical. Projecting portion 21 has an outer peripheral surface 140 arranged to surround imaginary axis CX parallel to output rotation axis BX, and groove portion 141 formed in at least a portion of outer peripheral surface 140 . 40 A of openings are provided in the protrusion part 21. As shown in FIG.

As shown in FIGS. 14 , 16 , 17 and 18 , a plurality of grooves 141 are provided on the outer peripheral surface 140 . In the embodiment, four grooves 141 are provided on the outer peripheral surface 140 . In the following description, the groove 141 provided on the upper left with respect to the virtual axis CX will be referred to as a groove 141A, and the groove 141 provided on the lower left with respect to the virtual axis CX will be referred to as a groove 141B. The groove portion 141 provided on the upper right with respect to the virtual axis CX is appropriately referred to as a groove portion 141C, and the groove portion 141 provided on the lower right with respect to the virtual axis CX is appropriately referred to as a groove portion 141D.

Grooves 141 (141A, 141B, 141C, 141D) are formed so as to extend in the circumferential direction around imaginary axis CX. The groove portion 141 is formed in an arc shape in a plane orthogonal to the virtual axis CX.

Further, as shown in FIGS. 14, 15, 17, and 18, the projection 21 has a recess 142 formed next to the groove 141 on the outer peripheral surface 140. As shown in FIGS. A plurality of recesses 142 are provided on the outer peripheral surface 140 . In the embodiment, two recesses 142 are provided on the outer peripheral surface 140 . In the following description, the recess 142 provided on the left with respect to the virtual axis CX will be referred to as a recess 142A, and the recess 142 provided on the right with respect to the virtual axis CX will be referred to as a recess 142B.

The concave portion 142 is formed between the first groove portion 141 and the second groove portion 141 adjacent to each other among the plurality of groove portions 141 . In the embodiment, the recess 142A is provided between the groove 141A and the groove 141B arranged next to the groove 141A. The groove portion 141B is provided below the groove portion 141A. The recess 142B is provided between the groove 141C and the groove 141D arranged next to the groove 141C. The groove portion 141D is provided below the groove portion 141C.

The recesses 142 (142A, 142B) are formed to extend vertically.

The space inside the recess 142A, the space inside the groove 141A, and the space inside the groove 141B are connected to each other. The space inside the recess 142B, the space inside the groove 141C, and the space inside the groove 141D are connected to each other.

As shown in FIGS. 14 and 18, a partition wall 151 is provided between the upper end of the groove 141A and the upper end of the groove 141C. A partition wall 152 is provided between the lower end of the groove 141B and the lower end of the groove 141D.

A partition wall 155 is provided between the lower end of the groove 141C and the upper end of the recess 142B. The space inside the groove portion 141</b>C and the space inside the recess portion 142</b>B are connected via a notch portion 165 provided in the partition wall 155 . A partition wall 156 is provided between the upper end of the groove 141D and the lower end of the recess 142B. The space inside the groove 141</b>D and the space inside the recess 142</b>B are connected via a notch 166 provided in the partition wall 156 . Similarly, a partition wall 153 is provided between the lower end of the groove 141A and the upper end of the recess 142A. The space inside the groove portion 141A and the space inside the recess portion 142A are connected via a notch portion 163 provided in the partition wall 153 . A partition wall 154 is provided between the upper end of the groove 141B and the lower end of the recess 142A. The space inside the groove portion 141B and the space inside the recess portion 142A are connected via a notch portion 164 provided in the partition wall 154 .

As shown in FIGS. 14 and 17 , a protrusion 143 is provided on the inner surface of the connecting portion 30 of the grip housing 3 .

The protrusion 143 provided on the connecting portion 30 of the grip housing 3 is arranged in the groove 141 provided on the protrusion 21 of the body housing 2 . A plurality of protrusions 143 are provided so as to be arranged in each of the plurality of grooves 141 . In the embodiment, four convex portions 143 are provided on the inner surface of the connecting portion 30 . In the following description, the convex portion 143 arranged in the groove portion 141A will be referred to as a convex portion 143A, the convex portion 143 arranged in the groove portion 141B will be referred to as a convex portion 143B, and the convex portion arranged in the groove portion 141C. The portion 143 is arbitrarily called a convex portion 143C, and the convex portion 143 arranged in the groove portion 141D is arbitrarily called a convex portion 143D.

Protrusions 143 (143A, 143B, 143C, 143D) are formed to extend in the circumferential direction about virtual axis CX. The convex portion 143 is formed in an arc shape in a plane perpendicular to the virtual axis CX.

As shown in FIGS. 14, 16, 17 and 18, the vibration isolating member 138 is arranged in the groove 141. As shown in FIG. A vibration isolating member 138 is arranged in each of the plurality of grooves 141 . In the embodiment, four anti-vibration members 138 are provided. In the following description, the vibration-isolating member 138 arranged in the groove 141A is appropriately referred to as a vibration-isolating member 138A, the vibration-isolating member 138 disposed in the groove 141B is appropriately referred to as a vibration-isolating member 138B, and the groove 141C The vibration isolating member 138 to be arranged is appropriately referred to as a vibration isolating member 138C, and the vibration isolating member 138 to be disposed in the groove portion 141D is appropriately referred to as a vibration isolating member 138D.

Anti-vibration members 138 (138A, 138B, 138C, 138D) extend in the circumferential direction about imaginary axis CX. The anti-vibration member 138 has an arc shape in a plane perpendicular to the virtual axis CX.

As shown in FIGS. 14 , 15 , 17 and 18 , vibration isolation member 139 is placed in recess 142 . A vibration isolating member 139 is arranged in each of the plurality of recesses 142 . In the embodiment, two anti-vibration members 139 are provided. In the following description, the vibration-isolating member 139 arranged in the recess 142A will be referred to as a vibration-isolating member 139A, and the vibration-isolating member 139 placed in the recess 142B will be referred to as a vibration-isolating member 139B.

The vibration isolating member 139 (139A, 139B) extends vertically. The vibration isolation member 139 has an upper end and a lower end.

The anti-vibration member 139 is arranged in the recess 142 so as to expand and contract in the rotational direction (vertical direction). The vibration isolating member 139 is elastically deformed at least in the rotational direction.

The inner surface of groove 141 includes a first support surface 144 , a second support surface 145 and a peripheral surface 146 . The first support surface 144 faces rearward. The second support surface 145 is arranged behind the first support surface 144 . The second support surface 145 faces forward. The peripheral surface 146 is connected to each of the radially inner end of the first support surface 144 and the radially inner end of the second support surface 145 . The peripheral surface 146 faces radially outward.

The vibration isolation member 138 includes a first vibration isolation portion 147 supported by the first support surface 144 , a second vibration isolation portion 148 supported by the second support surface 145 , and a third vibration isolation portion 148 supported by the peripheral surface 146 . and a vibrating portion 149 . The first vibration isolator 147 is elastically deformed at least in the axial direction (front-rear direction). The second vibration isolator 148 is elastically deformed at least in the axial direction (front-rear direction). The first vibration isolator 147 contacts the first support surface 144 . The second vibration isolator 148 contacts the second support surface 145 . The third vibration isolator 149 contacts the peripheral surface 146 .

The first vibration isolator 147 and the second vibration isolator 148 are arranged in the front-rear direction. The second vibration isolator 148 is arranged behind the first vibration isolator 147 . The first vibration isolator 147 and the second vibration isolator 148 face each other with a gap therebetween.

The convex portion 143 of the grip housing 3 is arranged between the first anti-vibration portion 147 and the second anti-vibration portion 148 . The convex portion 143A is arranged between the first vibration isolator 147 and the second vibration isolator 148 of the vibration isolator 138A. The convex portion 143B is arranged between the first vibration isolator 147 and the second vibration isolator 148 of the vibration isolator 138B. The convex portion 143C is arranged between the first vibration isolator 147 and the second vibration isolator 148 of the vibration isolator 138C. The convex portion 143D is arranged between the first vibration isolator 147 and the second vibration isolator 148 of the vibration isolator 138D.

A front surface of the projection 143 contacts the first vibration isolator 147 . The rear surface of the convex portion 143 contacts the second anti-vibration portion 148 . A radially inner inner surface of the projection 143 contacts the third vibration isolator 149 .

Also, at least a part of the convex portion 143 contacts the end portion of the anti-vibration member 139 arranged in the concave portion 142 . An end portion of the convex portion 143 in the rotation direction contacts an end portion of the vibration isolating member 139 arranged in the concave portion 142 .

The lower end of the projection 143A arranged in the groove 141A is connected to one end of the vibration isolating member 139A arranged in the recess 142A via a notch 163 formed in the partition wall 153 of the lower end of the groove 141A. touch some upper edge. The upper end of the anti-vibration member 139A contacts the lower end of the protrusion 143A while being inserted inside the notch 163. As shown in FIG. The upper end of the projection 143A arranged in the groove 141A is separated from the partition wall 151 of the upper end of the groove 141A. When the grip housing 3 rotates with respect to the body housing 2, the upper end of the protrusion 143A and the partition wall 151 come into contact with each other.

The upper end of the projection 143B arranged in the groove 141B is the other end of the anti-vibration member 139A arranged in the recess 142A via a notch 164 formed in the partition wall 154 of the upper end of the groove 141B. touch a lower edge. The lower end of the anti-vibration member 139A contacts the upper end of the projection 143B while being inserted inside the notch 164. As shown in FIG. The lower end of the projection 143B arranged in the groove 141B is separated from the partition wall 152 at the lower end of the groove 141B. When the grip housing 3 rotates with respect to the body housing 2, the bottom end of the projection 143B and the partition wall 152 come into contact with each other.

The anti-vibration member 139A is sandwiched between the lower end of the projection 143A and the upper end of the projection 143B.

The lower end of the projection 143C arranged in the groove 141C is connected to one end of the anti-vibration member 139B arranged in the recess 142B via a notch 165 formed in the partition wall 155 of the lower end of the groove 141C. touch some upper edge. The upper end of the anti-vibration member 139B comes into contact with the lower end of the protrusion 143C while being inserted inside the notch 165 . The upper end of the projection 143C arranged in the groove 141C is separated from the partition wall 151 at the upper end of the groove 141C. When the grip housing 3 rotates with respect to the body housing 2, the upper end of the protrusion 143C and the partition wall 151 come into contact with each other.

The upper end of the projection 143D arranged in the groove 141D is connected to the other end of the anti-vibration member 139B arranged in the recess 142B via a notch 166 formed in the partition wall 156 of the upper end of the groove 141D. touch a lower edge. The lower end of the anti-vibration member 139B comes into contact with the upper end of the projection 143D while being inserted inside the notch 166. As shown in FIG. The lower end of the projection 143D arranged in the groove 141D is separated from the partition wall 152 at the lower end of the groove 141D. When the grip housing 3 rotates with respect to the body housing 2, the bottom end of the protrusion 143D and the partition wall 152 come into contact.

The anti-vibration member 139B is sandwiched between the lower end of the projection 143C and the upper end of the projection 143D.

When the hammer case 6 vibrates in the axial direction parallel to the output rotation axis BX, the vibration transmitted from the hammer case 6 to the grip housing 3 via the main body housing 2 is transferred to the first vibration isolator contacting the front surface of the projection 143 . Attenuation is caused by elastic deformation of the second vibration isolator 148 that contacts the rear surface of the portion 147 and the convex portion 143 . That is, the vibration of the hammer case 6 in the axial direction parallel to the output rotation axis BX is suppressed from being transmitted to the grip housing 3 due to the elastic deformation of the vibration isolating member 138 in the axial direction.

When the hammer case 6 vibrates in the rotation direction about the output rotation axis BX, the vibration transmitted from the hammer case 6 to the grip housing 3 via the main body housing 2 contacts the end of the projection 143 in the rotation direction. It is attenuated by the elastic deformation of the anti-vibration member 139 . That is, the vibration of the hammer case 6 in the rotation direction about the output rotation axis BX is suppressed from being transmitted to the grip housing 3 due to the elastic deformation of the vibration isolation member 139 in the rotation direction.

[Action of impact tool]
Next, operation of the impact tool 1 will be described. For example, when performing a fastening operation on a work target, a socket used for the fastening operation is attached to the front end of the anvil 16 . After the socket is attached to the anvil 16, the operator grips the side handle 7 with the left hand, grips the grip portion 27 with the right hand, and moves the trigger lever 116 with the index and middle fingers of the right hand so that the trigger lever 116 moves backward. to operate. When the trigger lever 116 is operated to move backward, power is supplied from the battery pack 63 to the motor 10 to drive the motor 10 and light the light assembly 18 . Driving the motor 10 rotates the rotor 69 and the rotor shaft 70 . When the rotor shaft 70 rotates, the rotational force of the rotor shaft 70 is transmitted to the planetary gear 89 via the first bevel gear 80 , the second bevel gear 86 and the sun gear 88 . The planetary gear 89 revolves around the sun gear 88 while rotating while meshing with the internal teeth of the internal gear 90 . Planetary gear 89 is rotatably supported by spindle 14 via pin 93 . The revolution of the planetary gear 89 causes the spindle 14 to rotate at a rotational speed lower than that of the rotor shaft 70 .

As spindle 14 rotates while hammer projection 106 and anvil projection 114 are in contact, anvil 16 rotates with hammer 98 and spindle 14 . Fastening work progresses by rotating the anvil 16 .

As the fastening work progresses, when a load exceeding a predetermined value acts on the anvil 16, the anvil 16 and the hammer 98 stop rotating. When the spindle 14 rotates while the rotation of the hammer 98 is stopped, the hammer 98 moves backward. By moving the hammer 98 rearward, the contact between the hammer protrusion 106 and the anvil protrusion 114 is released. The hammer 98 that has moved backward moves forward while rotating due to the elastic force of the first coil spring 100 and the second coil spring 101 . As the hammer 98 rotates and moves forward, the anvil 16 is struck by the hammer 98 in the rotational direction. As a result, the anvil 16 rotates around the output rotation axis BX with high torque. Therefore, the bolts or nuts are tightened with high torque.

When a high load acts on anvil shaft portion 113 during fastening work, at least a portion of anvil shaft portion 113 may break. In the embodiment, the anvil shaft portion 113 is provided with a breakage starting portion 134 . Therefore, when a high load acts on anvil shaft portion 113 , anvil shaft portion 113 breaks at breakage starting point 134 as described with reference to FIG. 13 . When the anvil shaft portion 113 is broken at the breakage starting point 134 and the anvil shaft portion 113 ahead of the breakage starting point 134 moves forward with respect to the hammer case 6, the first rear side surface 127 of the first groove portion 121 It is caught by the suppressing member 123 . Therefore, the anvil shaft portion 113 ahead of the breakage starting portion 134 is prevented from coming off the impact tool 1 .

Vibration of the hammer case 6 generated during the fastening work is damped by the anti-vibration mechanism 137 . As a result, transmission of vibration of the hammer case 6 to the grip housing 3 via the body housing 2 is suppressed. Therefore, it is possible to prevent the workability of the fastening work from deteriorating and the operator who grips the grip housing 3 from feeling uncomfortable. Vibration of the controller 11 housed in the controller housing portion 28 of the grip housing 3 is suppressed. Therefore, the occurrence of malfunction of the controller 11 is suppressed.

[effect]
As described above, according to the embodiment, the impact tool 1 includes the motor 10, the impact mechanism 15 driven by the motor 10, the anvil 16 impacted in the rotational direction by the impact mechanism 15, and the impact mechanism 15. It is provided with a hammer case 6 to accommodate and an anvil bearing 115 . The striking mechanism 15 is rotatable around an output rotating shaft BX extending in the front-rear direction. The anvil 16 has an anvil shaft portion 113 arranged forwardly of the striking mechanism 15 and an anvil protrusion portion 114 protruding radially outward from the rear end portion of the anvil shaft portion 113 . The anvil projection 114 is struck by the striking mechanism 15 in the direction of rotation about the output rotation axis BX. The anvil bearing 115 is held by the hammer case 6 and arranged around the anvil shaft portion 113 . A first groove portion 121 is formed in the outer peripheral surface of the anvil shaft portion 113 so as to surround the output rotating shaft BX. A second groove portion 122 is formed in the inner peripheral surface of the anvil bearing 115 so as to surround the output rotating shaft BX. The impact tool 1 comprises a restraining member 123 including a first portion 124 arranged in the first groove portion 121 and a second portion 125 arranged in the second groove portion 122 .

In the above configuration, suppressing member 123 including first portion 124 arranged in first groove portion 121 and second portion 125 arranged in second groove portion 122 is provided, so that at least part of anvil shaft portion 113 is When broken, the anvil shaft portion 113 is caught by the suppressing member 123 supported by the second groove portion 122 . Therefore, the anvil shaft portion 113 is prevented from slipping forward from the hammer case 6 . Therefore, falling off of the anvil 16 from the impact tool 1 is suppressed.

In the embodiment, the suppressing member 123 has a ring shape surrounding the output rotation axis BX.

In the above configuration, when at least part of the anvil shaft portion 113 is broken, the anvil shaft portion 113 can be sufficiently caught by the suppressing member 123 supported by the second groove portion 122 .

In the embodiment, the suppressing member 123 is an O-ring that contacts the inner surface of the first groove portion 121 and the inner surface of the second groove portion 122, respectively.

In the above configuration, the boundary between the inner surface of the first groove portion 121 and the inner surface of the second groove portion 122 is sealed by the O-ring. Therefore, for example, grease supplied to the striking mechanism 15 is prevented from leaking from the boundary between the inner surface of the first groove portion 121 and the inner surface of the second groove portion 122 .

In the embodiment, the anvil shaft portion 113 has a breakage starting portion 134 with a smaller section modulus than the section modulus of the anvil shaft portion 113 in the first groove portion 121 . The breakage starting point 134 is arranged behind the first groove portion 121 .

In the above configuration, when a high load acts on anvil shaft portion 113 , anvil shaft portion 113 breaks at breakage starting point 134 . Since the anvil shaft portion 113 is broken behind the first groove portion 121 , the first groove portion 121 of the anvil shaft portion 113 can be caught by the suppressing member 123 supported by the second groove portion 122 .

In the embodiment, the impact tool 1 includes a third groove portion 135 formed in the outer peripheral surface of the anvil shaft portion 113 behind the first groove portion 121 so as to surround the output rotation axis BX. Diameter Db of anvil shaft portion 113 in third groove portion 135 is smaller than diameter Da of anvil shaft portion 113 in first groove portion 121 . Breakage starting portion 134 includes anvil shaft portion 113 in third groove portion 135 .

In the above configuration, the breakage starting portion 134 is easily formed by forming the third groove portion 135 .

In the embodiment, the inner surface of the first groove portion 121 includes a first front side surface 126 facing rearward, a first rear side surface 127 arranged behind the first front side surface 126 and facing forward, and a diameter of the first front side surface 126. a radially outwardly facing first circumferential surface 128 connected to each of the radially inner end and the radially inner end of the first rear side surface 127 . The inner surface of the second groove portion 122 includes a rearward facing second front side surface 129 and a radially inward facing second circumferential surface 131 connected to the radially outer end of the second front side surface 129 .

In the above configuration, since each of the first groove portion 121 and the second groove portion 122 is properly formed, when the anvil shaft portion 113 is broken at the breakage starting portion 134, the first groove portion 121 of the anvil shaft portion 113 is It can be caught on the suppressing member 123 supported by the second groove portion 122 .

In the embodiment, when the anvil shaft portion 113 is broken at the breakage starting portion 134 , the restraining member 123 contacts the first rear side surface 127 and the second front side surface 129 respectively.

In the above configuration, when the anvil shaft portion 113 is broken at the breakage starting point 134, the first rear side surface 127 of the first groove portion 121 is caught by the suppressing member 123 supported by the second front side surface 129 of the second groove portion 122. , the anvil shaft portion 113 is prevented from slipping forward from the hammer case 6 .

In embodiments, the hammer case 6 has a bearing support surface 132 that contacts the front end of the anvil bearing 115 .

In the above configuration, since the front end of the anvil bearing 115 contacts the bearing support surface 132 of the hammer case 6 , the anvil bearing 115 is prevented from slipping forward from the hammer case 6 . Even if the anvil shaft portion 113 is broken, the anvil bearing 115 does not come off forward from the hammer case 6 , so the suppressing member 123 supported by the second groove portion 122 of the anvil bearing 115 does not come off forward from the hammer case 6 either. Therefore, when at least a portion of the anvil shaft portion 113 is broken, the anvil shaft portion 113 is caught by the suppressing member 123 supported by the second groove portion 122, so that the anvil shaft portion 113 can be pulled out forward from the hammer case 6. Suppressed.

In embodiments, the anvil bearing 115 is a plain bearing.

In the above configuration, the second groove portion 122 is properly formed on the inner peripheral surface of the anvil bearing 115, which is a sliding bearing.

[Other embodiments]
In the above-described embodiment, the suppressing member 123 is a rubber O-ring. The suppressing member 123 may not be an O-ring, and may be a ring-shaped member made of synthetic resin or metal. Also, the suppressing member 123 may not be ring-shaped, and may be, for example, a snap ring.

In the above-described embodiment, in the plane orthogonal to the output rotation axis BX, the outer shape of the anvil shaft portion 113 in the first groove portion 121 is circular, and the outer shape of the anvil shaft portion 113 in the third groove portion 135 is circular. It was decided that Also, the diameter Db of the anvil shaft portion 113 in the third groove portion 135 is smaller than the diameter Da of the anvil shaft portion 113 in the first groove portion 121 . The outer shape of the anvil shaft portion 113 at the breakage starting point 134 may not be circular. It is sufficient that the section modulus of the breakage starting point 134 is smaller than the section modulus of the anvil shaft portion 113 in the first groove portion 121 .

In the above-described embodiment, the anvil bearing 115 is assumed to be a sliding bearing. Also, the second groove portion 122 is formed on the inner peripheral surface of the slide bearing. For example, the anvil bearing 115 may be composed of two ball bearings that are spaced apart in the front-rear direction. A gap between two ball bearings may function as the second groove portion 122 .

In the above-described embodiment, the anti-vibration member 138 is made of rubber. Anti-vibration member 138 may include a spring. In the above-described embodiment, the anti-vibration member 139 is a spring. The vibration isolation member 139 may contain rubber.

In the above-described embodiment, the vibration isolation member 138 is arranged in the groove 141 provided in the main body housing 2 , and the vibration isolation member 139 is arranged in the concave portion 142 provided in the main body housing 2 . In addition, the projection 143 provided on the grip housing 3 is brought into contact with each of the vibration isolating member 138 and the vibration isolating member 139 supported by the body housing 2 . The vibration isolating member 138 and the vibration isolating member 139 are respectively supported by the grip housing 3, and the protrusions provided on the main body housing 2 contact the vibration isolating member 138 and the vibration isolating member 139 supported by the grip housing 3, respectively. You may

In the above-described embodiment, the vibration isolation mechanism 137 includes a vibration isolation member 138 that suppresses transmission of vibration of the hammer case 6 in the axial direction parallel to the output rotation axis BX to the grip housing 3, and and a vibration isolating member 139 that suppresses transmission of vibration of the hammer case 6 in the direction of rotation to the grip housing 3 . The vibration isolation mechanism 137 may have the vibration isolation member 138 and may not have the vibration isolation member 139 . The vibration isolation mechanism 137 may have the vibration isolation member 139 and may not have the vibration isolation member 138 .

In the above-described embodiment, the impact tool 1 is an impact wrench. The impact tool may be an impact driver. The anvil of the impact driver has an insertion hole into which the tip tool is inserted, and a chuck mechanism that holds the tip tool.

In the above-described embodiment, the battery pack 63 attached to the battery attachment portion 9 is used as the power source for the impact tool 1 . A commercial power supply (AC power supply) may be used as the power supply for the impact tool 1 .

In the above-described embodiment, the motor 10 is an inner rotor type brushless motor. The motor 10 may be of the outer rotor type or may be a brushed motor.

DESCRIPTION OF SYMBOLS 1... Impact tool 2... Main body housing 2L... Left main body housing 2R... Right main body housing 3... Grip housing 3... Left grip housing 3R... Right grip housing 4... Motor housing 5... Gear case 6... Hammer case 7 Side handle 8 Bumper 9 Battery mounting part 10 Motor 11 Controller 12 Fan 13 Reduction mechanism 14 Spindle 15 Impact mechanism 16 Anvil 17 Trigger switch 18 Light assembly 19 Screw 20 Main body 21 Protruding part 22 Gear case housing part 23 Motor housing connection part 24 Cylindrical part 25 Rear wall part 26 Screw 27... Grip part 28... Controller accommodating part 29... Battery connector part 30... Connection part 31... Rear grip part 32... Upper grip part 33... Front grip part 34... Cylindrical part 35... Lower wall part , 36... Opening, 37... Opening, 38... Opening, 39... Opening, 40A... Opening, 40B... Opening, 41... Opening, 42... Opening, 43... Opening, 44... Bearing cover, 45... Screw, 46... First Cylindrical portion 47 Second cylindrical portion 48 Opening 49 Opening 50 Screw 51 Screw boss 52 Screw boss 53 Screw 54 Screw boss 55 Handle portion 56 Base portion , 57... First base part 58... Second base part 59... Hinge 60... Tightening mechanism 61... Screw 62... Dial part 63... Battery pack 64... Terminal 65... Terminal holder 66... Spring 67 Buffer member 68 Stator 69 Rotor 70 Rotor shaft 71 Stator core 72 Insulator 73 Coil 74 Busbar unit 75 Rotor core 76 Rotor magnet 77 Sensor substrate , 78... Rotor bearing 79... Rotor bearing 80... First bevel gear 81... Controller case 82... Intake port 83... Exhaust port 84... Intake port 85... Baffle plate 86... Second bevel gear 87... Planetary gear mechanism 88 Sun gear 89 Planetary gear 90 Internal gear 91 Gear bearing 92 Gear bearing 93 Pin 94 Flange 95 Spindle shaft 96 Projection 97 Spindle bearing 98 Hammer 99 Ball 100 First coil spring 101 Second coil spring 102 Third coil spring 103 First washer 104 Second washer 105 Hammer body 106 109 Ball 110 Spindle groove 111 Hammer groove 112 Anvil recess 113 Anvil shaft 114 Anvil projection 115 Anvil bearing 116 Trigger lever 117 Switch body 118 Circuit board 119 Light-emitting element 120 Light cover 121 First groove 122 Second groove 123 Suppressing member 124 First part 125 Second 2 parts, 126... First front side surface, 127... First rear side surface, 128... First peripheral surface, 129... Second front side surface, 130... Second rear side surface, 131... Second peripheral surface, 132... Bearing support surface , 133 Seal member 134 Breakage starting point 135 Third groove 136 Large-diameter portion 137 Anti-vibration mechanism 138 Anti-vibration member (first anti-vibration member) 138A Anti-vibration member 138B Vibration-isolating member 138C Vibration-isolating member 138D Vibration-isolating member 139 Vibration-isolating member (second vibration-isolating member) 139A Vibration-isolating member 139B Vibration-isolating member 140 Outer peripheral surface 141 Groove , 141A... groove, 141B... groove, 141C... groove, 141D... groove, 142... recess, 142A... recess, 142B... recess, 143... protrusion, 143A... protrusion, 143B... protrusion, 143C... protrusion, 143D 144 First support surface 145 Second support surface 146 Peripheral surface 147 First vibration isolator 148 Second vibration isolator 149 Third vibration isolator 151 Section Wall 152... Partitioning wall 153... Partitioning wall 154... Partitioning wall 155... Partitioning wall 156... Partitioning wall 163... Notch 164... Notch 165... Notch 166... Notch 181... Ring Spring 190 Screw 460 Cover BX Output rotary shaft CX Virtual shaft MX Motor rotary shaft Da Diameter Db Diameter.

Claims (9)

a motor;
a striking mechanism rotatable around an output rotary shaft extending in the front-rear direction and driven by the motor;
an anvil shaft disposed in front of the striking mechanism; and an anvil projection projecting radially outward from the rear end of the anvil shaft and struck by the striking mechanism in a rotational direction about the output rotation shaft. and an anvil having
a hammer case that houses the striking mechanism;
an anvil bearing held by the hammer case and arranged around the anvil shaft;
a first groove formed in the outer peripheral surface of the anvil shaft so as to surround the output rotary shaft;
a second groove formed in the inner peripheral surface of the anvil bearing so as to surround the output rotary shaft;
a suppressing member including a first portion arranged in the first groove and a second portion arranged in the second groove;
impact tool. The suppressing member has a ring shape surrounding the output rotation shaft,
The impact tool of Claim 1. The suppressing member is an O-ring that contacts the inner surface of the first groove and the inner surface of the second groove,
The impact tool according to claim 1 or 2. The anvil shaft portion has a breakage starting portion disposed rearward of the first groove portion and having a section modulus smaller than the section modulus of the anvil shaft portion in the first groove portion,
The impact tool according to any one of claims 1-3. a third groove formed in the outer peripheral surface of the anvil shaft so as to surround the output rotating shaft behind the first groove;
the diameter of the anvil shaft in the third groove is smaller than the diameter of the anvil shaft in the first groove;
The breakage starting portion includes the anvil shaft portion in the third groove portion,
An impact tool according to claim 4. The inner surface of the first groove portion includes a first front side surface facing rearward, a first rear side surface arranged rearward of the first front side surface and facing forward, a radially inner end portion of the first front side surface, and a radially outward facing first peripheral surface connected to each of the radially inner ends of the first rear side surface;
The inner surface of the second groove portion includes a second front side facing rearward and a second peripheral surface connected to a radially outer end of the second front side and facing radially inward,
The impact tool according to claim 4 or 5. In a state in which the anvil shaft portion is broken at the breakage starting portion, the suppressing member contacts the first rear side surface and the second front side surface, respectively.
An impact tool according to claim 6. The hammer case has a bearing support surface that contacts the front end of the anvil bearing.
An impact tool according to any one of claims 1 to 7. wherein the anvil bearing is a slide bearing;
An impact tool according to any one of claims 1-8.

Images