DE102022127106A1 - IMPACT TOOL - Google Patents

Abstract

Objective: Limit detachment of an anvil. Solution: An impact tool (1) comprises a motor (10), an impact mechanism (15) rotatable about an output pivot axis (BX) and operatively driven by the motor (10), an anvil ( 16) having an anvil shank portion (113) disposed in front of the striking mechanism and a radially outwardly projecting anvil projection portion (114) struck in a rotating direction by the striking mechanism, a hammer case (6) accommodating the striking mechanism, an anvil bearing (115) held by the hammer housing and surrounding the anvil shank portion, a first groove portion (121) formed on an outer peripheral surface of the anvil shank portion so as to encircle the output rotation axis, a second groove portion (122) formed on a An inner peripheral surface of the anvil bearing formed so as to encircle the output axis of rotation, and a retaining member (123) having a first portion (124) disposed in the first groove portion and a second portion (125) disposed in the second groove portion is arranged.

Description

TECHNICAL AREA

The techniques disclosed herein relate to an impact tool.

STATE OF THE ART

JP 6 801 571 B2 discloses a known bump key.

SHORT SUMMARY

The known striking tool mentioned above has an anvil. If an excessively heavy load (e.g., a large torque and/or bending moment) acts on the anvil and causes the anvil to break, there is a possibility that at least a portion of the anvil will detach (fall off, fall out, separate) from the striking tool ).

A non-limiting object of the present teachings is to disclose techniques for reducing the possibility of a portion of the anvil detaching (separating) from the striking tool in the event that the anvil breaks (breaks, breaks off) during use of the striking tool.

The object mentioned above is solved by an impact tool according to claim 1 .

In one non-limiting aspect of the present teachings, an impact tool may include a motor, an impact mechanism driven by the motor, an anvil that is impacted in a rotational direction by the impact mechanism, a hammer housing that houses the impact mechanism, and an anvil bearing. The striking mechanism may be rotatable about an output pivot axis extending in the front-rear direction. The anvil may include an anvil shank portion (anvil shank) disposed forward of the striking mechanism, and an anvil projection portion (anvil projection) protruding radially from a rear end portion of the anvil shank portion. The anvil projection portion can be struck in a rotational direction by the striking mechanism and thereby rotated about the output rotational axis. The anvil bearing may be carried by the hammer housing and disposed around (surround) the anvil shank portion. A first groove part (first groove) may be formed (defined) on an outer peripheral surface of the anvil shaft part so as to encircle (encircle) the output rotation axis. A second groove part (second groove) may be formed (defined) on an inner peripheral surface of the anvil bearing so as to encircle (encircle) the output rotation axis. The impact tool may include a holding member having a first portion disposed in the first groove portion and a second portion disposed in the second groove portion.

According to the one or more techniques disclosed in the present specification, it is possible to reduce the likelihood that a portion of the anvil will detach (fall out) from the impact tool in the event that the anvil breaks during use.

character list

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

DETAILED DESCRIPTION

As noted above, an impact tool may include a motor, an impact mechanism driven by the motor, an anvil impacted in a rotational direction by the impact mechanism, a hammer housing housing the impact mechanism, and an anvil bearing. The striking mechanism may be rotatable about an output pivot axis extending in the front-rear direction. The anvil may include an anvil shank portion (anvil shank) disposed forward of the striking mechanism, and an anvil projection portion (anvil projection) protruding radially from a rear end portion of the anvil shank portion. The anvil projection portion can be struck in a rotational direction by the striking mechanism and thereby rotated about the output rotational axis. The anvil bearing may be carried by the hammer housing and disposed around (surround) the anvil shank portion. A first groove part (first groove) may be formed (defined) on an outer peripheral surface of the anvil shaft part so as to encircle (encircle) the output rotation axis. A second groove part (second groove) may be formed (defined) on an inner peripheral surface of the anvil bearing so as to encircle (encircle) the output rotation axis. The impact tool may include a holding member having a first portion disposed in the first groove portion and a second portion disposed in the second groove portion.

According to the configuration described above, by providing the holding member having the first portion disposed inside the first groove part and the second portion disposed inside the second groove part, even if a portion of the anvil shaft part (anvil shaft) is damaged during the operation of the striking tool, the broken portion of the anvil shank portion can be caught (blocked) by the retaining member which is supported by the second groove portion of the anvil bearing (which is retained by the hammer housing) so that the broken portion of the anvil shank portion does not become detached from the striking tool (from this separates, detaches, falls out). That is, the broken part of the anvil shank part is restrained (blocked, prevented, restrained) from detaching (falling out) from the hammer housing in the forward direction. Accordingly, it is possible to reduce the possibility that the broken part of the anvil comes off the striking tool in the event that the anvil shaft part breaks during use.

In one or more embodiments, the retaining member may have an annular shape that encircles (encircles) the output pivot axis.

According to the configuration described above, if a portion of the anvil shaft part is broken off, the anvil shaft part can be sufficiently (reliably) caught by the annular retaining member supported by the second groove part.

In one or more embodiments, the retention member may be an O-ring that contacts both an inner (e.g., circumferentially extending) surface of the first groove portion and an inner (e.g., circumferentially extending) surface of the second groove portion. For example, the O-ring may preferably contact both of a radially outward peripheral surface of the first groove portion and a radially inward peripheral surface of the second groove portion.

According to the configuration described above, the boundary (gap, space) between the inner surface of the first groove part and the inner surface of the second groove part is sealed by the O-ring. Accordingly, e.g., a lubricant supplied to the percussion mechanism is prevented from leaking (leaking, flowing out) from (through) the boundary (gap, space) between the inner surface of the first groove part and the inner surface of the second groove part.

In one or more embodiments, the anvil shank portion may have a predetermined breaking point area (fracture start point area) having a section modulus less than the section modulus of the anvil shank portion at (along, inside) the first groove portion. The predetermined breaking point area can be arranged on the rear of the first groove part.

According to the configuration described above, if an excessively heavy load acts on the anvil shank portion, the shank portion will tend to be broken at the breaking point portion. If the shank portion rearward of the first groove portion breaks, the first groove portion of the anvil shank portion can still be caught (blocked, prevented) by the retaining member supported (held) by the second groove portion of the anvil bearing (which is firmly held by the hammer housing), thereby the broken-off portion of the anvil stem portion from detaching (separating) from the striking tool is blocked in the forward direction of the striking tool.

In one or more embodiments, the impact tool may have a third groove part (third groove) formed (defined) on the outer peripheral surface of the anvil shank part rearward of the first groove part (in the axial direction of the anvil shank part) and encircling (encircling) the output rotation axis. The diameter of the anvil shank portion at (along, inside) the third groove portion may be smaller than the diameter of the anvil shank portion at (along, inside) the first groove portion. In other words, the outer diameter of a radially outward-facing (facing) peripheral surface of the first groove portion may be larger than the outer diameter of a radially outward-facing (facing) peripheral surface of the third groove portion. The area of weakness may include the anvil shank portion in the third groove portion. In other words, the breaking point area may be defined or located within the dimension (length) of the third groove part in the axial direction of the anvil shank part.

According to the above-described configuration, by forming the third groove part in this way, the breaking point portion can be formed in a simple manner.

In one or more embodiments, the inner surface of the first groove portion may include a front (e.g., radially extending) first surface facing rearwardly (in the axial direction of the anvil shank portion), a rearward (e.g., radially extending) first surface, rearwardly facing the first front surface and facing forward (in the axial direction of the anvil shank part), and having a first peripheral surface connected to a radially inner end portion of the first front surface and to a radially inner end portion of the first rear surface, and the first peripheral surface points radially outwards. The inner surface of the second groove part may have a second front (e.g. radially extending) surface facing rearwardly (in the axial direction of the anvil shank part) and a second peripheral surface which is connected to a radially outer end portion of the second front surface and which second peripheral surface faces radially inward.

According to the configuration described above, the first groove part and the second groove part are formed (defined) in an advantageous manner. For example, if the anvil shank portion breaks at (or along) the frangible area, the first groove portion of the anvil shank portion may be caught by the restraining member which is supported by the second groove portion or the anvil bearing, thereby blocking (restraining, restraining) the fractured portion of the anvil shank portion. will detach (fall out) from the striking tool.

In one or more embodiments, the first groove portion and second groove portion may be configured (defined, dimensioned) such that the retaining member may contact the first rear surface and the second front surface in the event the anvil shank portion is fractured at the frangible area.

According to the configuration described above, when the anvil shank portion is broken at (or along) the breaking point portion, since the first rear surface of the first groove portion is caught by the retaining member supported (held therein) by the second front surface of the second groove portion, the anvil shank portion is restrained (blocked, prevented) from detaching from the hammer housing in the forward direction.

In one or more embodiments, the hammer housing may have a bearing seating surface that contacts (comes in contact with) a front end portion of the anvil bearing (in the axial direction of the anvil shank part).

According to the configuration described above, since the front end portion of the anvil bearing contacts the bearing mounting surface of the hammer case, the anvil bearing is restrained (locked) from coming off (falling out) from the hammer case in the forward direction. Even if the anvil shank part breaks, since the anvil bearing does not detach (fall out) from the hammer housing in the forward direction, the retaining member, which is held (supported) by the second groove part of the anvil bearing, will also not detach from the hammer housing to the forward direction (fall out). Accordingly, if a portion of the anvil shank portion is broken, the anvil shank portion is restrained (blocked) from detaching (falling out) from the hammer housing in the forward direction due to the broken portion of the anvil shank portion being caught by the retaining member supported by the second groove portion becomes.

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

According to the configuration described above, the second groove part can be suitably positioned on the inner peripheral surface of the anvil bearing configured (designed, constructed) as a slide bearing.

Embodiments according to the present disclosure will be described below with reference to the drawings, but the present disclosure is not limited to the embodiments. Structural elements of the embodiments described below may be combined as appropriate. In addition, there are situations where some of the structural elements are not used.

In the embodiments, positional relationships between parts are described using the terms "left", "right", "front", "back", "top" and "bottom". These terms indicate relative positions or directions with respect to the center of an impact tool 1 . A left-right direction, a front-back direction, and a top-bottom direction are all mutually perpendicular.

striking tool

1 14 is a front left perspective view of the impact tool 1 according to an embodiment. 2 14 is a rear right perspective view of the impact tool 1 according to the embodiment. 3 14 is a right side view of the impact tool 1 according to the embodiment. 4 12 is a left view of the impact tool 1 according to the embodiment. 5 12 is a rear view of the impact tool 1 according to the embodiment. 6 12 is a front view of the impact tool 1 according to the embodiment. 7 12 is a plan view of the impact tool 1 according to the embodiment. 8th 12 is a bottom view of the impact tool 1 according to the embodiment. 9 14 is a cross-sectional view of the impact tool 1 according to the embodiment, and corresponds to a cross-sectional view taken along line BB in FIG 7 . 10 12 is a cross-sectional view of the impact tool 1 according to the embodiment, and corresponds to a cross-sectional view taken along line AA in FIG 3 .

In the embodiment, the impact tool 1 is an impact wrench, which is a kind of fastening tool. The impact tool 1 has a main body case 2, a handle case 3, a motor case 4, a gear case 5, a hammer case 6, a side handle 7, a damper 8, a battery mounting part 9, a motor 10, a controller 11, an impeller 12, a speed reduction mechanism 13, a spindle 14, an impact mechanism 15, an anvil 16, a trigger switch 17 and a light assembly 18.

The main body case 2 accommodates the gear case 5. At least a portion of the main body case 2 is disposed at the front of the handle case 3. At least a portion of the main body case 2 is located above the motor case 4 . The main body case 2 is arranged at the rear of the hammer case 6 . The main body case 2 is coupled to the handle case 3 . The main body case 2 is connected to the motor case 4 . The main body case 2 is fixed to the hammer case 6 .

The main body case 2 is made of synthetic resin (polymer). Nylon (polyamide) is an exemplary example of the synthetic resin that forms the main body case 2 . The main body case 2 includes a left main body case 2L and a right main body case 2R, which is located on the right of the left main body case 2L. The left main body case 2L and the right main body case 2R form a pair of half cases. The left main body case 2L and the right main body case 2R are fixed to each other by a plurality of screws 19 .

The main body casing 2 has a main body part 20 and a protruding part 21 which protrudes rearward from the main body part 20 . The main body part 20 has a gear housing receiving part 22 which receives the gear housing 5 and a motor housing connecting part 23 which is connected to the motor housing 4 . The gear housing receiving part 22 has a tubular part 24 which is arranged around the gear housing 5 and a rear wall part 25 which is arranged at a rear end portion of the tubular part 24 . The motor case connection part 23 is arranged so as to protrude downward from a rear portion of the gear case receiving part 22 . The motor case connection part 23 is arranged at the rear of the motor case 4 . The protruding part 21 is coupled to the handle housing 3 . A portion of the protruding part 21 protrudes rearward from the gear housing receiving part 22 . A portion of the protruding part 21 protrudes rearward from the motor case connecting part 23 .

The grip case 3 is configured (designed, constructed) to be gripped by a user. The handle housing 3 accommodates the controller 11 . The handle case 3 supports the trigger switch 17. At least a portion of the handle case 3 is arranged at the rear of the main body case 2. As shown in FIG. The handle case 3 is connected to the main body case 2 is coupled to be movable relative to the main body case 2 .

The grip case 3 is made of a synthetic resin (polymer). Nylon (polyamide) is an exemplary example of the synthetic resin that forms the grip case 3 . The grip case 3 has a left grip case 3L and a right grip case 3R which is arranged on the right of the left grip case 3L. The left grip case 3L and the right grip case 3R form a pair of half cases. The left grip case 3L and the right grip case 3R are fixed to each other by a plurality of screws 26 .

The grip case 3 has a grip part 27 configured (designed, constructed) to be gripped by the user, a controller receiving part 28 receiving the controller 11, a battery connecting part 29 on which the battery mounting part 9 is arranged, and a coupling part 30 which is coupled to the protruding part 21 of the main body case 2 . The grip portion 27 has a rear grip portion 31 which extends upward from a rear portion of the control receiving portion 28, an upper grip portion 32 which extends forward from an upper end portion of the rear grip portion 31, and a front grip portion 33 which extends downward from a front end portion of the upper handle portion 32. The front grip part 33 is arranged so as to connect a front end portion of the upper grip part 32 and an upper portion of the coupling part 30 . The grip part 27 is formed in a substantially ring shape. The trigger switch 17 is arranged at an upper portion of the rear grip part 31 . The battery connection part 29 is arranged at a lower portion of the controller receiving part 28 . At least a portion of the battery connection part 29 is arranged in front of the controller receiving part 28 . The coupling part 30 is arranged at a front portion of the control receiving part 28 .

The motor housing 4 accommodates the motor 10 . The motor case 4 is arranged downward from the transmission case 5 . The motor case 4 is connected to the main body case 2 . The motor housing 4 is fixed to the transmission housing 5 .

The motor case 4 is formed of a synthetic resin (polymer). Polycarbonate is an exemplary example of the synthetic resin that forms the motor case 4 .

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

An opening 36 is provided at an upper portion of the motor case 4 . An opening 37 is formed at a lower portion of the gear case receiving portion 22 .

An opening 38 is provided in a rear portion of the motor case 4 . An opening 39 is provided in the motor housing connection part 23 . An opening 40A is provided at a rear portion of the main body case 2 . An opening 40B is provided in a front portion of the grip case 3. As shown in FIG. The interior of the motor housing 4 and the interior of the controller accommodating part 28 are connected via the opening 38, the opening 39, the opening 40A and the opening 40B.

The transmission case 5 accommodates at least a portion of the speed reduction mechanism 13 . The gear housing 5 is arranged at the rear of the hammer housing 6 . The gear case 5 is fixed to the hammer case 6 .

The gear case 5 is made of a metal. Aluminum and magnesium are exemplary examples of the metal that forms the gear case 5 .

The transmission case 5 is substantially tubular in shape. An opening 41 is provided in a front portion of the transmission case 5 . An opening 42 is provided in a rear portion of the transmission case 5 . An opening 43 is provided in a lower portion of the transmission case 5 . A bearing cover 44 is arranged within the opening 42 of the transmission case 5 . The bearing cover 44 is fixed to a rear portion of the transmission case 5 by bolts 45 .

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

The hammer case 6 is made of a metal. Aluminum is an exemplary example of the metal that forms the hammer case 6 .

The hammer case 6 has a substantially tubular shape. The hammer housing 6 has a first tube part 46 and a second tube part 47 . The first tube part 46 is arranged around the striking mechanism 15 . The second tube part 47 is arranged in front of the first tube part 46 in the axial direction of the anvil 16 . The outer diameter of the second tube part 47 is smaller than the outer diameter of the first Pipe part 46. An opening 48 is provided in a rear portion of the first pipe part 46. As shown in FIG. An opening 49 is provided in a front portion of the second pipe part 47 . A front end portion of the transmission case 5 is inserted into the opening 48 .

The gear case 5 and the hammer case 6 are fixed by a plurality of bolts 50 . The transmission housing 5 has a plurality of screw attachments 51 . At least a portion of the main body case 2 is arranged to cover the screw bosses 51 . The main body case 2 is also fixed to the hammer case 6 by the plurality of bolts 50 . The hammer housing 6 has a plurality of screw attachments 52 . The bolts 50 are inserted into through holes provided in the main body case 2 and through holes provided in the screw bosses 51 of the gear case 5 . The bolts 50 are inserted into bolt holes provided in the bolt bosses 52 of the hammer case 6 . The screws 50 are inserted into through holes in the main body case 2 and through holes in the screw lugs 51 from the back of the screw lugs 51 , and then they are inserted into the screw holes of the screw lugs 52 .

The motor case 4 and the transmission case 5 are fixed to each other by a plurality of bolts 53 . The motor housing 4 has a plurality of screw attachments 54 . The bolts 53 are inserted into through holes provided in the bolt bosses 54 of the motor case 4 . The bolts 53 are inserted into bolt holes provided in a lower portion of the gear case 5 . The bolts 53 are inserted into through holes of the bolt lugs 54 from below the bolt lugs 54, after which they are inserted into the screw holes of the gear case 5.

The interior of the motor housing 4 and the interior of the gear housing 5 are connected via the opening 36 and the opening 43 .

The interior of the gear case 5 and the interior of the hammer case 6 are connected via the opening 41 and the opening 48 .

Referring now to 1 and 5 until 8th the side handle 7 is configured to be gripped by a user. The side handle 7 has a handle part 55 which is gripped by the user and a base part 56 which is fixed to the hammer case 6 . The handle part 55 is arranged to the left of the hammer housing 6 . The base portion 56 includes a first base portion 57 and a second base portion 58 disposed downward from the first base portion 57 . The first base part 57 and the second base part 58 each have an arc shape. The first base part 57 and the second base part 58 are arranged to sandwich the first tube part 46 of the hammer case 6 . A cover 460 is arranged at an upper portion of the first pipe part 46 . At least a portion of the first base 57 overlaps the cover 460 . A right end portion of the first base 57 and a right end portion of the second base 58 are coupled by hinges 59 . A left end portion of the first base 57 and a left end portion of the second base 58 are connected to the handle portion 55, respectively. A left end portion of the first base 57 and a left end portion of the second base 58 are coupled via a clamp mechanism 60 . The tightening mechanism 60 includes a screw 61 disposed within a screw hole provided in a left end portion of the second base 58 and a rotary wheel 62 rotatable relative to the screw 61 . The user can rotate the rotary wheel 62 by operating the rotary wheel 62 manually. By manually rotating the rotary knob 62, the distance between the left end portion of the first base 57 and the left end portion of the second base 58 can be changed. By rotating the screw 61 so that the distance between the left end portion of the first base 57 and the left end portion of the second base 58 becomes shorter, the base 56 is tightened to (tightened, clamped around) the hammer body 6, whereby the side handle 7 is fixed to the hammer case 6.

It is noted that, in the embodiment, although the handle portion 55 is disposed to the left of the hammer case 6, the handle portion 55 may be disposed at any position around the circumference of the hammer case 6. For example, the handle portion 55 may be placed leftward of the hammer case 6, upward of the hammer case 6, or downward of the hammer case 6. The position (angle) of the handle part 55 relative to the hammer housing 6 is continuously changeable over the entire 360° range.

The damper 8 is arranged to cover at least a portion of the surface of the hammer case 6 . In the embodiment, the damper 8 is arranged to cover the surface of the first pipe part 46 . The damper 8 protects the hammer case 6. The damper 8 protects the hammer case 6 from objects around the striking tool 1. The damper 8 is formed of an elastic body (material) softer (elastic) than that Hammer housing 6 is. Styrene butadiene rubber is an exemplary example of the elastic body that forms the damper 8 .

Referring now to 1 and 9 the battery mounting part 9 is provided on the battery connection part 29 . A battery pack 63 is mounted on the battery mounting part 9 . A portion of the battery connection part 29 is arranged upward of the battery pack 63 which is arranged on the battery mounting part 9 . A portion of the battery connection part 29 is arranged in front of the battery pack 63 mounted on the battery mounting part 9 . The battery pack 63 functions as a power supply (power source) of the impact tool 1 . The battery pack 63 includes secondary batteries. In the embodiment, the battery pack 63 includes rechargeable lithium-ion batteries. When mounted on the battery mounting part 9 , the battery pack 63 can supply electric power to the impact tool 1 . The motor 10 operates using electric power supplied from the battery pack 63 . The controller 11 is operated using electric power supplied from the battery pack 63 .

The battery mounting part 9 has a terminal block 64 in the form of a plate. The terminal block 64 has a board made of a synthetic resin (polymer) and connection terminals made of a metal and arranged on (in) the board. By mounting the battery pack 63 on the battery mounting part 9, the connection terminals of the battery pack 63 electrically connect to the connection terminals of the terminal block 64. The terminal block 64 is held by a terminal holder 65. FIG. The terminal holder 65 is sandwiched between the left grip case 3L and the right grip case 3R. A spring 66 and a cushioning member 67 are arranged at a portion of the battery connection part 29 which portion is located in front of the battery pack 63 . The spring 66 is arranged in front of the terminal holder 65 . The spring 66 is supported by a portion of the battery connector 29 which portion is located in front of the terminal block 64 . The spring 66 biases the terminal holder 65 rearward. The cushioning member 67 is arranged in front of the battery pack 63 mounted on the battery mounting part 9 . The cushioning member 67 is supported by a portion of the battery connection part 29 which is located in front of the battery pack 63 mounted on the battery mounting part 9 . Rubber is an exemplary example of the cushioning member 67. The cushioning member 67 is (comes) in contact with a front portion of the battery pack 63. For example, in the event that the impact tool 1 falls, the impact applied to the terminal block 64 is cushioned by the elastic force of the spring 66 , and the impact that acts on the battery pack 63 is cushioned by the cushioning member 67 .

The motor 10 functions as the driving power source (driving motor) of the impact tool 1. The motor 10 is a brushless inner rotor type motor. The motor 10 has a stator 68 , a rotor 69 and a rotor shaft 70 . The stator 68 is supported by the motor housing 4 . At least a portion of the rotor 69 is disposed inside (inside) the stator 68 . The rotor shaft 70 is fixed to the rotor 69 . The rotor 69 is rotatable relative to the stator 68 about a motor rotation axis MX extending in the up-down direction.

The stator 68 has a stator core 71, an insulator 72 and coils 73. FIG.

The stator core 71 is arranged radially outside of the rotor 69 . The stator core 71 has a plurality of laminated steel discs. Each of the steel disks is a disk made of a metal of which iron is the main component. The stator core 71 has a yoke having a tubular shape and a plurality of teeth projecting radially inward from an inner peripheral surface of the yoke.

The insulator 72 is an electrically insulating member made of synthetic resin (polymer). At least a portion of the insulator 72 is provided at an upper portion of the stator core 71 . At least a portion of the insulator 72 is provided at a lower portion of the stator core 71 . At least a portion of the insulator 72 is arranged to cover surfaces of the teeth of the stator core 71 .

The coils 73 are mounted on the teeth of the stator core 71 via the insulator 72, respectively. The stator core 71 and the coils 73 are electrically insulated from each other by the insulating piece 72 . The coils 73 are connected to each other via a bus bar unit 74 .

The rotor 69 rotates about a motor rotation axis MX. The rotor 69 includes a rotor core 75 and a rotor magnet or magnets 76 .

The rotor core 75 has a plurality of laminated steel discs. The rotor core 75 has a tubular shape.

The rotor magnet(s) 76 is (are) fixed to the rotor core 75 . At the execution ing shape, the rotor magnet(s) 76 is (are) arranged inside the rotor core 75.

A sensor board 77 is fixed to the insulator 72 . The sensor board 77 detects the position of the rotor 69 in the direction of rotation. The sensor board 77 has a circuit board having a ring shape and a rotation detecting device supported by the circuit board. At least a portion of the sensor board 77 faces the rotor magnet(s) 76 . By detecting the position(s) of the rotor magnet(s) 76, the rotation detection device detects the position of the rotor 69 in the direction of rotation.

The rotor shaft 70 is arranged inward (inside) of the rotor core 75 . The rotor shaft 70 is fixed to the rotor core 75 . The rotor 69 and the rotor shaft 70 rotate together about the motor rotation axis MX. An upper end portion of the rotor shaft 70 projects upward from an upper end surface of the 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 supported in a rotatable manner by a rotor bearing 78 and a rotor bearing 79 . The rotor bearing 78 rotatably supports an upper portion of the rotor shaft 70 which is located upward from the upper end surface of the rotor core 75 . The rotor bearing 79 supports, in a rotatable manner, a lower portion of the rotor shaft 70 which is located downward from a lower end surface of the rotor core 75 . The rotor bearing 78 is held by the gear case 5 . The rotor bearing 79 is held by the motor case 4 .

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

The controller 11 outputs control signals that control the motor 10 . The controller 11 has a circuit board on which a plurality of electric parts are mounted. A processor such as a CPU (Central Processing Unit), a non-volatile memory such as a ROM (read only memory) and a storage device, a volatile memory such as a RAM (random access memory), field effect transistors (FET: field -effect transistor) and resistors are exemplary examples of the electronic parts mounted on the circuit board.

The controller 11 is housed within the controller accommodating part 28 of the handle housing 3 . Within the controller accommodating portion 28, the controller 11 is held by a controller case 81. As shown in FIG.

The fan 12 creates an air flow for cooling the motor 10 and the controller 11. The fan 12 is disposed upwardly from the stator 78 of the motor 10. FIG. The fan wheel 12 is fixed to an upper area of the rotor shaft 70 . The fan wheel 12 is arranged between the rotor bearing 78 and the stator core 71 . The fan wheel 12 and the rotor shaft 70 rotate together. Air intake openings 82 are provided in the lower wall part 35 of the motor housing 4 . Air outlet openings 83 are provided in a front upper portion, a left upper portion, and a right upper portion of the pipe part 34 of the motor housing 4 . Air suction openings 82 are provided in a left area and a right area of the controller receiving part 28 . By rotating the fan wheel 12 , air will flow from the outside of the motor housing 4 into the interior of the motor housing 4 via the air intake openings 82 . The air that has flowed into the interior of the motor housing 4 flows through the interior of the motor housing 4, whereby the motor 10 is cooled. By rotating the fan 12 , at least part of the air that has flowed through the interior of the motor housing 4 is discharged to the outside of the motor housing 4 via the air outlet openings 83 . Furthermore, by rotating the fan wheel 12 , air will flow from the outside of the handle housing 3 into the interior of the controller receiving part 28 via the air intake openings 84 . The air that has flowed into the inside of the controller accommodating part 28 flows through the inside of the controller accommodating part 28, whereby the controller 11 is cooled. By rotating the fan 12 , the air that has flowed through the inside of the controller accommodating part 28 is discharged to the outside of the motor case 4 via the air discharge ports 83 .

In the embodiment, a baffle 85 is interposed between the fan 12 and the stator 68 . The baffle 85 guides the air flowing in response to the rotation of the fan 12 .

The speed reduction mechanism 13 transmits the rotational power of the motor 10 to the impact mechanism 15 via the spindle 14. The speed reduction mechanism 13 operatively couples the rotor shaft 70 and the spindle 14. The speed reduction mechanism 13 causes the spindle 14 to rotate at a speed less than the RPM of the rotor shaft 70 is.

The speed reduction mechanism 13 has a second bevel gear 86 meshing with the first bevel gear 80 and a planetary gear mechanism 87 which is driven by the rotational force of the engine 10 transmitted to 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 within the gear case 5 . The internal gear 90 is fixedly held so that it is not rotatable relative to the case 2 .

The second bevel gear 86 is arranged around the sun gear 88 . The 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 about an output rotation axis BX extending in the front-rear direction. The output rotation axis BX and the motor rotation axis MX are perpendicular to each other. 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 . Rotating the rotor shaft 70 and thereby rotating the first bevel gear 80 rotates the second bevel gear 86. Rotating the second bevel gear 86 rotates the sun gear 88.

Each of the planetary gears 89 meshes with the sun gear 88. The planetary gears 89 are each supported in a rotatable manner by pins 93 on the spindle 14. The spindle 14 is rotated by the planetary gears 89 . The internal gear 90 has internal teeth which mesh with the planetary gears 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 . The protruding parts of the internal gear 90 are each positively engaged with recessed parts (recesses) provided on (in) the inner peripheral surface of the gear case 5 . The internal gear 90 is always non-rotatable relative to the gear case 5 .

By operating (exciting) the motor 10, the rotor shaft 70 and the first bevel gear 80 will rotate, and thus the second bevel gear 86 and the sun gear 88 will rotate. When the sun gear 88 rotates, the planetary gears 89 revolve around the sun gear 88. The planetary gears 89 revolve while meshing with the internal teeth of the internal gear 90. Due to the rotation of the planetary gears 89, the spindle 14, which is connected to the planetary gears 89 via the pins 93, rotates at a speed which is less than the speed of the rotor shaft 70.

The spindle 14 rotates due to the rotational force of the motor 10 transmitted through the speed reduction mechanism 13 . The spindle 14 transmits the rotational force of the motor 10, which has been transmitted through the speed reduction mechanism 13, to the percussion mechanism 15. The spindle 14 is rotatable about the output rotation axis BX. A rear portion of the spindle 14 is housed within the transmission case 5 . A front portion of the spindle 14 is housed within the hammer case 6 . At least a portion of the spindle 14 is arranged in front of the speed reduction mechanism 13 . The spindle 14 is arranged at the rear of the anvil 16 .

Referring now to 9 and 10 the spindle 14 has a flange portion 94, a spindle shaft portion 95 which protrudes forward from the flange portion 94 in the axial direction of the spindle 14, and a protruding portion 96 which protrudes rearward from the flange portion 94 in the axial direction of the spindle 14 . The planetary gears 89 are each supported in a rotatable manner by the flange portion 94 and the protruding portion 96 via the pins 93 . The spindle 14 is supported in a rotatable manner by a spindle bearing 97 . The spindle bearing 97 supports the protruding part 96 in a rotatable manner. The spindle bearing 97 is held by the gear case 5 .

The striking mechanism 15 strikes the anvil 16 in the rotating direction, thereby rotating the anvil 16 about the output rotating axis BX. The striking mechanism 15 is driven by the motor 10 . The striking mechanism 15 is rotatable about the output pivot axis BX. The rotational force of the motor 10 is transmitted to the impact mechanism 15 via the speed reduction mechanism 13 and the spindle 14 . The striking mechanism 15 strikes the anvil 16 in the rotational direction using the rotational force of the spindle 14 rotated by the motor 10.

The striking mechanism 15 is accommodated within the first tubular part 46 of the hammer housing 6 . The striking mechanism 15 comprises a hammer 98, balls 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 at the front of the speed reduction mechanism 13 . The hammer 98 is positioned around the spindle 14 . The hammer 98 is held by the spindle 14. The balls 99 are positioned between the spindle 14 and the hammer 98 . The hammer 98 has a hammer body 105 having a tubular shape and hammer projection parts 106 provided at a front portion of the hammer body 105 . An annular recessed part 107 is provided on a rear surface of the hammer body 105 . The recessed part 107 is recessed forward from a rear surface of the hammer body 105 .

The hammer 98 is placed around the spindle shaft portion 95 . The hammer 98 has a hole 108 in which the spindle shaft portion 95 is located.

The hammer 98 is rotated by the 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. FIG. The hammer 98 is rotatable together with the spindle 14 using the rotational force of the spindle 14 which is rotated by the motor 10. The hammer 98 and spindle 14 each rotate about the output axis of rotation BX.

The first washer 103 is arranged inside (inside) of the recessed part 107 . The first washer 103 is supported by the hammer 98 through a plurality of balls 109 . The balls 109 are arranged in front of the first washer 103 .

The second washer 104 is disposed rearward of the first washer 103 inside (inside) the recessed portion 107 . The outer diameter of the second washer 104 is smaller than the outer diameter of the first washer 103. The second washer 104 and the hammer 98 are movable relative to the front-rear direction.

The first coil spring 100 is disposed around (surrounds) 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 disposed inside (inside) of the recessed portion 107 and supported by the first washer 103 . The first coil spring 100 continuously generates an elastic force that causes the hammer 98 to move forward (biases, urges the hammer 98 forward).

The second coil spring 101 is disposed around (surrounds) the spindle shaft portion 95 . The second coil spring 101 is arranged radially inside (inside) of the first coil spring 100 . A rear end portion of the second coil spring 101 is supported by the flange portion 94 . A front end portion of the second coil spring 101 is located inside (inside) of the recessed part 107 and supported by the second washer 104 . When the hammer 98 moves backward, the second coil spring 101 generates an elastic restoring force, which causes the hammer 98 to move forward (return).

The third coil spring 102 is disposed around (surrounds) the spindle shaft portion 95 . The third coil spring 102 is arranged radially inside (inside) of the first coil spring 100 . The third coil spring 102 is arranged inside (inside) the recessed part 107 . A rear end portion of the third coil spring 102 is supported by the 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 biases the second coil spring 101 rearward. A rear end portion of the second coil spring 101 is pressed against the flange part 94 due to the elastic force of the third coil spring 102 . As a result, the second coil spring 101 is held firmly with respect to the flange portion 94 .

The balls 99 are made of a metal such as steel. The balls 99 are arranged between the spindle shaft part 95 and the hammer 98 . The spindle 14 has a spindle groove 110 in which at least one of the balls 99 is arranged. The spindle groove 110 is provided on a portion of the outer surface of the spindle shaft part 95 . The hammer 98 has a hammer groove 111 in which at least some of the balls 99 are located. The hammer groove 111 is provided on an inner surface portion of the hammer 98 . The balls 99 are located between the spindle groove 110 and the hammer groove 111 . The balls 99 can roll along the inside of the spindle groove 110 and the inside of the hammer groove 111 . The hammer 98 is movable along with the balls 99. Spindle 14 and hammer 98 can each move relative to each other within a movable range defined by spindle groove 110 and hammer groove 111 in a direction parallel to output pivot axis BX and in a direction about output pivot axis BX.

The anvil 16 is the output part of the striking tool 1 and is rotated in response to the rotation power output by the engine 10 is rotated. At least a portion of the anvil 16 is forward of the hammer 98 .

The anvil 16 has an anvil recess part (anvil recess, anvil blind hole) 112 . The anvil recess part 112 is provided at (in) a rear end portion of the anvil 16 . The anvil recessed portion 112 is recessed forward from the rear end portion of the anvil 16 . The spindle 14 is arranged at the rear of the anvil 16 . A front end portion of the spindle shaft portion 95 is located within the anvil cavity portion 112 .

The anvil 16 has an anvil shank portion (anvil shank) 113 and anvil projection portions (projections, flanges, wings) 114 . The anvil shaft part 113 is arranged in front of the striking mechanism 15 in the axial direction of the anvil shaft part 113 . The anvil projection portions 114 protrude radially outward of the anvil shank portion 113 from a rear end portion of the anvil shank portion 113 . The anvil projection parts 114 are struck in the rotational direction by the striking mechanism 15 and are thus rotated about the output rotational axis BX, whereby the anvil shank part 113 is rotated.

A front end portion of the anvil shank part 113 is located in front of the hammer case 6 via the opening 49 in the axial direction of the anvil shank part 113 . A tool accessory, such as a socket, can be mounted on the forward end portion of the anvil shank portion 113 .

The anvil 16 is supported in a rotatable manner by an anvil bearing 115 . Anvil bearing 115 is disposed around (surrounds) anvil shank portion 113 . The anvil 16 is rotatable about the dispensing axis of rotation BX. The anvil bearing 115 is held by the hammer case 6 . The anvil bearing 115 is disposed inside (inside) the second tubular portion 47 of the hammer case 6 . The anvil bearing 115 is held by the second tubular part 47 of the hammer housing 6 .

The trigger switch 17 is manually operated by the user to operate (operate) the motor 10 . The operation of the motor 10 is related to the coils 73 of the stator 68 being energized causing the rotor 69 to rotate. The trigger switch 17 is provided at an upper portion of the rear grip portion 31 . The push switch 17 has a push lever 116 and a switch main body 117 . The switch main body 117 is arranged in the inner space of the rear grip part 31 . The pusher lever 116 protrudes forward from an upper end portion of a front portion of the rear grip 31 . The pusher lever 116 is manually operated (pressed) by the user to move rearward. By manually actuating trigger lever 116 to move rearward, motor 10 is operated (energized). By releasing the manual operation (pressing) of the trigger lever 116, the operation (energization) of the motor 10 stops.

The light assembly 18 emits an illumination light. The light assembly 18 illuminates the anvil 16 and the periphery of the anvil 16 with an illuminating light. The light assembly 18 illuminates the front of the anvil 16 with an illuminating light. The light assembly 18 also illuminates the socket that has been assembled to the anvil 16 and the vicinity of the socket with an illuminating light. In the embodiment, the light assembly 18 includes a circuit board 118, a light emitting device 119 installed on a front surface of the circuit board 118, and an annular light cover 120 disposed in front of the circuit board 118. The light cover 120 is arranged to cover the light emitting device 119 . The light assembly 18 is arranged around the second tubular part 47 of the hammer housing 6 . A ring spring 181, which restrains the light assembly 18 from disengaging from the second tube portion 47 in the forward direction, is disposed in front of the light assembly 18. As shown in FIG.

retention component

11 12 is a partial cross-sectional view of the impact tool 1 according to the embodiment, and corresponds to a partial enlarged view of FIG 9 . 12 12 is a partial cross-sectional view of the impact tool 1 according to the embodiment, and corresponds to a partial enlarged view of FIG 10 .

In 11 and 12 a direction parallel to the output rotation axis BX is referred to as the axial direction when appropriate, a direction that is about the output rotation axis BX is referred to as the circumferential direction or the rotation direction when appropriate, and a radial direction of the output rotation axis BX is referred to as the radial Direction indicated when appropriate. Furthermore, in the radial direction, a location closer to or a direction approaching the output rotation axis BX is referred to as radially inward (or inward in the radial direction) as appropriate, and a location away from or a direction , leading away from the output axis of rotation BX is referred to as radially outward (or outward in the radial direction) where appropriate.

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

As in 11 and 12 1, a first groove portion (a first groove) 121 is formed on (in) the outer peripheral surface of the anvil shank portion 113, preferably such that it encircles (encircles) the output pivot axis BX.

A second groove part (a second groove) 122 is formed on (in) the inner peripheral surface of the anvil bearing 115, preferably such that it encircles (encircles) the output rotation axis BX.

In the embodiment, the anvil bearing 115 is a plain bearing. The second groove part 122 is formed on an inner peripheral surface of the plain bearing. The anvil bearing 115 has a tubular shape. A sleeve is used as the anvil bearing 115 in the embodiment. It is noted that, for example, a plain bearing can be formed by impregnating a tubular metal porous body made by a powder metallurgy method with a lubricating oil.

The striking tool 1 has a retaining member 123 which restrains (blocks) a (broken off) portion of the anvil shank portion 113 from detaching (falling out) from the hammer housing 6 (i.e., separating or detaching from the striking tool 1) in the forward direction in the fall , hindered) in which the anvil shank part 113 breaks during operation of the striking tool 1. The retaining member 123 has a first portion 124 located inside (in contact with) the first groove portion 121 and a second portion 125 located inside (in contact with) the second groove portion 122 . The first area 124 is the radially inner area of the retaining member 123 . The second area 125 is the radially inner area of the retaining member 123 and is located further radially outward than the first area 124 .

The retaining member 123 has a ring shape that encircles (encircles) the output rotation axis BX. In the embodiment, the retaining member 123 is an O-ring contacting both of the inner surface of the first groove part 121 and the inner surface of the second groove part 122 .

The inner surface of the first groove part 121 has a first front (radially extending) surface 126 , a first rear (radially extending) surface 127 and a first peripheral surface 128 . The first front surface 126 faces rearward in the axial direction of the anvil shank portion 113 . The first rear surface 127 is arranged rearward of the first front surface 126 in the axial direction of the anvil shank part 113 . The first rear surface 127 faces forward in the axial direction of the anvil shank portion 113 . The first peripheral surface 128 is connected to (i) an end portion of the first front surface 126 that is on the radially inner side and (ii) an end portion of the first rear surface 127 that is on the radially inner side. The first peripheral surface 128 faces radially outward with respect to the axial direction (axis of rotation) of the anvil shank portion 113.

The inner surface of the second groove portion 122 has a second front (radially extending) surface 129 , a second rear (radially extending) surface 130 and a second peripheral surface 131 . The second front surface 129 faces rearward in the axial direction of the anvil shank portion 113 . The second rear surface 130 is arranged rearward of the second front surface 129 in the axial direction of the anvil shank part 113 . The second rear surface 130 faces forward in the axial direction of the anvil shank portion 113 . The second peripheral surface 131 is connected to (i) an end portion of the second front surface 129 that is on the radially outer side and (ii) an end portion of the second rear surface 130 that is on the radially outer side. The second peripheral surface 131 faces radially inward with respect to the axial direction (axis of rotation) of the anvil shank portion 113.

In the embodiment, the depth of the first groove part 121 and the depth of the second groove part 122 are substantially equal to each other. It is noted that the depth of the first groove part 121 may be greater than the depth of the second groove part 122, or depth of the second groove part 122 may be greater than the depth of the first groove part 121. The depth of the first groove part 121 refers to the dimension of the first groove part 121 in the radial direction. That is, the depth of the first groove part 121 refers to the distance between the outer peripheral surface of the anvil shank part 113 and the first peripheral surface 128 in the radial direction. The depth of the second groove part 122 refers to the dimension of the second groove part 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 which contacts (slidably supports) the anvil shank portion 113 and the second peripheral surface 131 in the radial direction.

The dimension (axial length) of the first groove part 121 in the axial direction is shorter than the dimension (axial length) of the second groove part 122 in the axial direction. The dimension of the first groove part 121 in the axial direction refers to the distance between the first front surface 126 and the first back surface 127. The dimension of the second groove part 122 in the axial direction refers to the distance between the second front surface 129 and of the second rear surface 130. In the examples shown in FIG 11 and 12 1, the position of the first front surface 126 and the position of the second front surface 129 in the axial direction are substantially the same. The first rear surface 127 is located in front of the second rear surface 130 in the axial direction of the anvil shank part 113 .

It is noted that the position of the first front surface 126 and the position of the second front surface 129 in the axial direction may be different from each other. The first rear surface 127 may be located in front of the second rear surface 130 in the axial direction of the anvil shaft part 113 , or may be located rear of the second rear surface 130 in the axial direction of the anvil shaft part 113 .

The retaining member 123 is arranged such that it (i.e., the first portion 124) contacts the first peripheral surface 128 and that it (i.e., the second portion 125) contacts the second peripheral surface 131. As described above, in the embodiment, the retaining member 123 is an O-ring. The retaining member 123 is somewhat compressed by the first peripheral surface 128 and the second peripheral surface 131 . The retaining member 123 seals the boundary (gap, space) between the first peripheral surface 128 and the second peripheral surface 131.

In the examples given in 11 and 12 1, the retaining member 123 is arranged to contact both the first front surface 126 and the second front surface 129. As shown in FIG. The retaining member 123 seals the boundary (gap, space) between the anvil shank portion 113 and the anvil bearing 115.

The hammer housing 6 has a bearing bearing surface 132 which contacts a front end of the anvil bearing 115 . The bearing mounting surface 132 is provided at a front end portion of the second pipe part 47 . The bearing mounting surface 132 faces rearward. The bearing seating surface 132 pushes the anvil bearing 115 from the front. The bearing support surface 132 restrains (blocks) the anvil bearing 115 from detaching (falling out) from the hammer case 6 in the forward direction. Within a plane perpendicular to the output rotation axis BX, the bearing support surface 132 has a tubular shape. The opening 49 is defined radially inward of the bearing mounting surface 132 .

A front end portion of the anvil shaft portion 113 is located at the front of the second tube portion 47 through the opening 49. At least a portion of the anvil shaft portion 113 is located inside the opening 49. As shown in FIG. A sealing member 133 is provided at a front end portion of the second pipe part 47 . The sealing member 133 is arranged in the interior of the opening 49 . The sealing member 133 seals the boundary (gap, space) between a front end portion of the second pipe part 47 and the anvil shaft part 113. The sealing member 133 is arranged in front of the retaining member 123 in the axial direction of the anvil shaft part 113.

The anvil shank part 113 has a predetermined breaking point area (breaking start point area) 134 which is arranged on the rear of the first groove part 121 . The section modulus of the anvil shank portion 113 at (along, inside) the predetermined breaking point area 134 is smaller (lower) than the section modulus of the anvil shank part 113 at (along, inside) the first groove portion 121. That is, the modulus of resistance of the anvil shank portion 113 passing through the predetermined breaking point area 134 passes through and is perpendicular to the payout pivot axis BX is smaller than the section modulus of the anvil shank portion 113 that passes through the first groove portion 121 and is perpendicular to the payout pivot axis BX. In the case of the anvil shank part 113, the breaking point area 134 is the area in which the strength in relation to the bending moment is the lowest. That is, for the anvil shank portion 113, the area of weakness 134 is the area most likely to break when the anvil shank portion 113 is subjected to an excessively heavy load. Further or alternatively, the cross-sectional area (cross-sectional area) of the anvil shank portion 113 in a first plane perpendicular to the axial direction (axis of rotation) of the anvil shank portion 113, which first plane passes through the frangible portion 134, is smaller (smaller) than the cross-sectional area (cross-sectional area) of the anvil shank part 113 in a second plane perpendicular to the axial direction (axis of rotation) of the anvil shank part 113, which second plane passes through the first groove part 121.

A third groove part (third groove) 135 is on (in) the outer peripheral surface of the anvil shank part 113 formed (defined). The third groove part 135 is formed rearward of the first groove part 121 in the axial direction of the anvil shank part 113 . The third groove part 135 is formed on the outer peripheral surface of the anvil shaft part 113 so as to encircle (encircle) the output rotation axis BX.

The depth of the third groove part 135 is greater than the depth of the first groove part 121. The depth of the third groove part 135 refers to the dimension of the third groove part 135 in the radial direction. A diameter Db of the anvil shank portion 113 at (along, in) the third groove portion 135 is smaller than a diameter Da of the anvil shank portion 113 at (along, in) the first groove portion 121. The frangible area 134 includes the anvil shank portion 113 at the third groove portion 135. In other words, the breaking point portion 134 is defined within the dimension (axial length) of the third groove part 135 in the axial direction of the anvil shank part 113 . In the axial direction, a large-diameter part 136 of the anvil shank part 113, the diameter of which is larger than the diameter Da and the diameter Db, is provided (disposed) between the first groove part 121 and the third groove part 135. The first rear surface 127 is located at a front portion of the large-diameter part 136 .

13 12 is a cross-sectional view showing the state where a portion of the anvil shaft part 113 according to the embodiment is broken. For example, if an excessive heavy load acts on the anvil shank part 113 during fastening work, there is a possibility that at least a portion of the anvil shank part 113 will break. In the embodiment, the breaking point portion 134 is provided at (in) the anvil shank portion 113 . Accordingly, if an excessively heavy load acts on the anvil shank portion 113, the anvil shank portion 113 is designed (constructed) to break (first) at the breakneck portion 134, as shown in FIG 13 shown.

Here, if the anvil shank part 113 breaks at the breaking point portion 134 , there is a possibility that the (broken) portion of the anvil shank part 113 that is at the front of the breaking point portion 134 moves forward relative to the hammer case 6 . However, according to the embodiment, if the broken portion of the anvil shaft part 113 moves forward, the first rear surface 127 of the first groove part 121 is caught (blocked, restrained, prevented) by the retaining member 123 so that the broken portion of the anvil shaft part 113 blocks thereon is to exit the hammer case 6 (exit the hammer case 6).

As noted above, a front end portion of the anvil bearing 115 comes (is) in contact with the bearing bearing surface 132 of the hammer housing 6. Therefore, even if the anvil shank portion 113 breaks, the anvil bearing 115 will not move forward relative to the hammer housing 6. Moreover, the retaining member 123 is supported by (contacts) the second front surface 129 of the second groove part 122 . Therefore, the retaining member 123, which is supported by (contacts) the second front surface 129 of the anvil bearing 115, will not move forward relative to the hammer housing 6 either. As in 13 As shown, in the state where the anvil shank portion 113 is fractured at the frangible portion 134, the retaining member 123 contacts the first rear surface 127 and the second front surface 129. Therefore, the fractured portion of the anvil shank portion 113 is caught by the retaining member 123 (blocked, restrained, prevented) so that it will not move forward relative to the hammer housing 6. Accordingly, when the anvil shank portion 113 breaks (breaks off) at (along, within) the breaking point portion 134, the broken portion of the anvil shank portion 113 is restrained (blocked, prevented) from moving away from the hammer housing 6 in the forward direction in the axial direction of the anvil shaft part 113 detaches (falls out). That is, if the anvil shank portion 113 is broken, the broken portion of the anvil shank portion 113, which is in front of the breaking point portion 134, is restrained (blocked, prevented) from detaching (falling out, separating, separating) from the impact tool 1.

vibration damping mechanism

14 12 is a partial cross-sectional view of the impact tool 1 according to the embodiment, and corresponds to a cross-sectional view taken along line CC in FIG 9 . 15 12 is a partial cross-sectional view of the impact tool 1 according to the embodiment, and corresponds to a cross-sectional view taken along line DD in FIG 14 . 16 12 is a partial cross-sectional view of the impact tool 1 according to the embodiment, and corresponds to a drawing, when viewed from above (the E direction), of a cross section taken along line E′-E′ in FIG 14 . 17 14 is a partially exploded perspective view of the impact tool 1 according to the embodiment. 18 14 is a partially exploded perspective view of the impact tool 1 according to the embodiment.

As in 14 until 18 As shown, the impact tool 1 has a vibration damping mechanism 137 . The vibration damper Mechanism 137 dampens (isolates) the transmission of vibration from the hammer case 6 to the handle case 3 via the main body case 2. Vibration normally arises in the hammer case 6 during operation due at least to the rotation of the anvil 16 during fastening work, from the impacts on the anvil 16 by the impact mechanism 15 and/or by the load carried by the anvil 16 from the work piece. When a vibration of the hammer case 6 is transmitted to the handle case 3 via the main body case 2, the handle case 3 shakes (vibrates), and there is a possibility that the working efficiency of the fastening work decreases, the user holding the handle case 3 feels discomfort, or similar. Due to the damping (damping) of the transmission of the vibration of the hammer case 6 to the handle case 3 via the main body case 2 by the vibration damping mechanism 137, the occurrence of a decrease in working efficiency of the fastening work, the occurrence of the feeling of discomfort by the user gripping the handle case 3 , and the like are insulated (reduced). In addition, in the embodiment, the controller 11 is housed within the controller accommodating portion 28 of the handle case 3 . When the controller 11 vibrates, there is a possibility of occurrence of malfunction of the controller 11. Due to the damping (damping) of transmission of the vibration of the hammer case 6 to the handle case 3 by the vibration damping mechanism 137, the vibration of the controller 11 can be damped (reduced). .

The vibration-isolating mechanism 137 has vibration-isolating members 138 and vibration-isolating members 139 disposed between the main body case 2 and the handle case 3 . The vibration isolating members 138 and the vibration isolating members 139 each dampen (dam) the transmission of the vibration of the hammer case 6 to the handle case 3 via the main body case 2.

As described above, the main body case 2 has the main body part 20 and the protruding part 21 which protrudes rearward from the main body part 20 . The grip case 3 has the coupling part 30 coupled to the protruding part 21 . The vibration isolating members 138 and the vibration isolating members 139 are each disposed between the protruding part 21 and the coupling part 30 .

It is noted that, as in 14 and 15 As shown, the protruding part 21, the left main body case 2L and the right main body case 2R are fixed to each other by a screw 190.

Each of the vibration isolating members 138 is a first vibration isolating member that dampens (reduces) the transmission of the vibration of the hammer case 6 in the axial direction parallel to the output rotation axis BX of the handle case 3 via the main body case 2 . Each of the vibration damping members 138 is formed from a rubber or other type of elastomer. In the embodiment, each of the vibration damping members 138 is a rubber damper.

Each of the vibration isolating members 139 is a second vibration isolating member that dampens (reduces) the transmission of the vibration of the hammer case 6 in the rotational direction centered on the output rotational axis BX to the handle case 3 via the main body case 2 . Each of the vibration isolating members 139 has a spring. In the embodiment, each of the vibration isolating members 138 is a compression spring.

As in 17 and 18 As shown, the outer shape of the protruding part 21 is substantially a circular columnar shape. The protruding part 21 has an outer peripheral surface 140 arranged to encircle (encircle) a virtual axis CX parallel to the output rotation axis BX, and groove parts (grooves) 141 formed in at least portions of the outer peripheral surface 140 are. The opening 40A is provided in the protruding part 21. As shown in FIG.

As in 14 and 16 until 18 1, a plurality of the groove parts (grooves) 141 are provided on the outer peripheral surface 140. As shown in FIG. In the embodiment, four of the groove parts 141 are provided on the outer peripheral surface 140 . In the following description, the groove part 141 provided on the upper left side of the virtual axis CX is referred to as a groove part 141A, where appropriate, the groove part 141 provided on the lower left side of the virtual axis CX is referred to as a groove part 141B denotes where appropriate, the groove part 141 provided at the upper right side of the virtual axis CX is referred to as the groove part 141C where appropriate and the groove part 141 provided at the lower right side of the virtual axis CX referred to as groove portion 141D where appropriate.

The groove parts 141 (141A, 141B, 141C, 141D) are formed so as to extend in the circumferential direction around the virtual axis CX. Within a plane perpendicular to the virtual On the axis CX, each of the groove parts 141 is formed in an arc shape.

Furthermore, as in 14 , 15 , 17 and 18 As shown, the protruding part 21 has recessed parts (recesses) 142 formed adjacent to the groove parts (grooves) 141 on the outer peripheral surface 140 . A plurality of the recessed parts 142 are provided on the outer peripheral surface 140 . In the embodiment, two of the recessed parts 142 are provided on the outer peripheral surface 140 . In the following description, the recessed part 142 provided on the left of the virtual axis CX is referred to as recessed part 142A when appropriate, and the recessed part 142 provided on the right of the virtual axis CX is referred to as recessed part 142B as appropriate .

The recessed parts 142 are formed between the first groove parts 141 among the plurality of groove parts 141 and the second groove parts 141 among the plurality of groove parts 141 adjacent to each other. In the embodiment, the recessed part 142A is provided between the groove part 141A and the groove part 141B which is located adjacent to the groove part 141A. The groove part 141B is provided downward from the groove part 141A. The recessed part 142B is provided between the groove part 141C and the groove part 141D which is adjacent to the groove part 141C. The groove part 141D is provided downward from the groove part 141C.

The recessed parts 142 (142A, 142B) are formed so as to extend in the top-bottom direction.

The space inside (inside) of the recessed part 142A, the space inside (inside) of the groove part 141A, and the space inside (inside) of the groove part 141B are connected to each other. The space inside (inside) of the recessed part 142B, the space inside (inside) of the groove part 141C, and the space inside (inside) of the groove part 141D are connected to each other.

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

A partition wall 155 is provided between a lower end portion of the groove portion 141C and an upper end portion of the recessed portion 142B. The space inside (inside) of the groove part 141C and the space inside (inside) of the recessed part 142B are connected via a notched part 165 provided on the partition wall 155 . A partition wall 156 is provided between an upper end portion of the groove portion 141D and a lower end portion of the recessed portion 142B. The inside space (inside) of the groove part 141D and the inside space (inside) of the recessed part 142B are connected via a notched part 166 provided on the partition wall 156 . Similarly, a partition wall 153 is provided between a lower end portion of the groove portion 141A and an upper end portion of the recessed portion 142A. The inside space (inside) of the groove part 141A and the inside space (inside) of the recessed part 142A are connected via a notched part 163 provided on the partition wall 153. As shown in FIG. A partition wall 154 is provided between an upper end portion of the groove portion 141B and a lower end portion of the recessed portion 142A. The inside space (inside) of the groove part 141B and the inside space (inside) of the recessed part 142A are connected via a notched part 164 provided on the partition wall 154. As shown in FIG.

As in 14 and 17 1, protruding parts 143 are provided on the inner surface of the coupling part 30 of the handle housing 3. As shown in FIG.

The protruding parts 143 provided on the coupling part 30 of the handle housing 3 are located in the groove parts 141 provided on the protruding part 21 of the main body housing 2, respectively. A plurality of the protruding parts 143 are provided such that the protruding parts 143 are located in the groove parts 141, respectively. In the embodiment, four of the protruding parts 143 are provided on the inner surface of the coupling part 30 . In the following description, the protruding part 143 arranged in the groove part 141A will be referred to as the protruding part 143A, where appropriate, the protruding part 143 arranged in the groove part 141B will be referred to as the protruding part 143B, where appropriate, the projecting part 143 arranged in the groove part 141C is called projecting part 143C when appropriate, and projecting part 143 arranged in the groove part 141D is called projecting part 143D when appropriate.

The protruding parts 143 (143A, 143B, 143C, 143D) are formed so as to extend in the circumferential direction around the virtual axis CX, within a plane perpendicular to the On the virtual axis CX, each of the protruding parts 143 is formed in an arc shape.

As in 14 and 16 until 18 1, the vibration isolating members 138 are disposed in the groove portions 141. As shown in FIG. Each of the vibration isolating members 138 is disposed in the corresponding groove portion 141 . In the embodiment, four of the vibration isolating members 138 are provided. In the following description, the vibration isolating member 138 disposed in the groove portion 141A is called vibration isolating member 138A, when appropriate, the vibration isolating member 138 is disposed in the groove portion 141B is called vibration isolating member 138B, when appropriate, is called vibration isolating member 138 disposed in The vibration isolating member 138 disposed in the groove part 141C is referred to as vibration isolating member 138C as appropriate, and the vibration isolating member 138 arranged in the groove portion 141D is referred to as vibration isolating member 138D as appropriate.

The vibration isolating members 138 (138A, 138B, 138C, 138D) extend in the circumferential direction around the virtual axis CX. Within a plane perpendicular to the virtual axis CX, each of the vibration isolating members 138 has an arc shape.

As in 14 , 15 , 17 and 18 As shown, the vibration isolating members 139 are disposed in the recessed portions 142, respectively. That is, each of the vibration isolating members 139 is disposed in a corresponding one of the recessed parts 142 . In the embodiment, two of the vibration isolating members 139 are provided. In the following description, the vibration isolating member 139 located in the recessed portion 142A is referred to as vibration isolating member 139A, as appropriate, and the vibration isolating member 139 that is in the recessed portion 142B is referred to as vibration isolating member 139B, as appropriate.

The vibration isolating members 139 (139A, 139B) extend in the up-down direction. Each of the vibration isolating members 139 has an upper end portion and a lower end portion.

The vibration isolating members 139 are arranged in the recessed portions 142 such that the vibration isolating members 139 expand (elongate) and contract (compress) in the rotating direction (up-down direction). The vibration isolating members 139 elastically deform at least in the rotational direction.

Each of the inner surfaces of the groove parts 141 has a first bearing surface 144 , a second bearing surface 145 and a peripheral surface 146 . The first bearing surfaces 144 face rearward in the axial direction of the anvil shaft part 113. The second bearing surfaces 145 are arranged rearward of the first bearing surfaces 144 in the axial direction of the anvil shaft part 113. The second bearing surfaces 145 face forward in the axial direction of the anvil shank part 113. The peripheral surfaces 146 are connected to radially inner end portions of the first bearing surfaces 144 and to radially inner end portions of the second bearing surfaces 145, respectively. The peripheral surfaces 146 each face radially outward.

The vibration isolating members 138 have first vibration isolating portions 147 supported by the first supporting surfaces 144, second vibration isolating portions 148 supported by the second supporting surfaces 145, and third vibration isolating portions 149 supported by the peripheral surfaces 146. The first vibration-isolating portions 147 elastically deform at least in the axial direction (front-back direction) of the anvil shaft part 113. The second vibration-isolating portions 148 elastically deform at least in the axial direction (front-back direction). The first vibration-isolating portions 147 come (stand) in contact with the first bearing surfaces 144, respectively. The second vibration-isolating portions 148 come (stand) in contact with the second bearing surfaces 145, respectively. The third vibration-isolating portions 149 come (stand) in contact with the peripheral surfaces 146, respectively.

The first vibration-isolating portions 147 and the second vibration-isolating portions 148 are spaced in the front-rear direction and preferably extend parallel to each other. The second vibration isolating portions 148 are arranged rearwardly of the first vibration isolating portions 147 . The first vibration isolating portions 147 and the second vibration isolating portions 148 face each other across a gap.

The protruding parts 143 of the handle housing 3 are arranged between the first vibration-isolating portions 147 and the second vibration-isolating portions 148, respectively. The protruding part 143A is between the first Vibration isolating portions 147 and the second vibration isolating portion 148 are disposed at the vibration isolating member 138A. The protruding part 143B is arranged between the first vibration-isolating portion 147 and the second vibration-isolating portion 148 of the vibration-isolating member 138B. The protruding part 143C is arranged between the first vibration-isolating portion 147 and the second vibration-isolating portion 148 of the vibration-isolating member 138C. The protruding part 143D is arranged between the first vibration-isolating portion 147 and the second vibration-isolating portion 148 of the vibration-isolating member 138D.

The front surfaces of the protruding parts 143 come (are) in contact with the first vibration-isolating portions 147, respectively. The rear surfaces of the protruding parts 143 come (are) in contact with the second vibration-isolating portions 148, respectively. The radially inner surfaces of the protruding parts 143 come ( are) each in contact with the third vibration damping areas 149.

Furthermore, at least a portion of each of the protruding parts 143 comes (is) in contact with an end portion of the corresponding vibration isolating member 139 arranged in the corresponding recessed part 142 . The end portions of the protruding parts 143 in the direction of rotation come (stand) in contact with the end portions of the vibration-isolating members 139 arranged in the recessed parts 142 .

A lower end portion of the protruding part 143A, which is located in the groove part 141A, comes (stands) in contact with an upper end portion, which is an end portion of the vibration isolating member 139A, which is located in the recessed part 142A, via the notched part 163 , which is formed on the partition wall 153, at the lower end portion of the groove part 141A. The upper end portion of the vibration isolating member 139A comes (stands) in contact with a lower end portion of the protruding part 143A in the state where the upper end portion of the vibration isolating member 139A is inserted inside the notched part 163 . An upper end portion of the protruding part 143A, which is located in the groove part 141A, is spaced from the partition wall 151 at an upper end portion of the groove part 141A. If the handle housing 3 rotates relative to the main body housing 2, e.g., due to vibration and/or torsion during operation of the impact tool 1, the upper end portion of the protruding part 143A and the partition wall 151 will contact (touch) each other.

An upper end portion of the protruding part 143B, which is located in the groove part 141B, comes (stands) in contact with a lower end portion, which is the other end portion of the vibration isolating member 139A, which is located in the recessed part 142A, via the notched part 164 , which is formed on the partition wall 154, at an upper end portion of the groove part 141B. The lower end portion of the vibration isolating member 139A comes into contact with an upper end portion of the protruding part 143B in the state where the lower end portion of the vibration isolating member 139A is inserted inside the notched part 164 . A lower end portion of the protruding part 143B, which is located in the groove part 141B, is spaced from the partition wall 152 at a lower end portion of the groove part 141B. If the grip case 3 rotates relative to the main body case 2, e.g., due to vibration or torsion during operation of the impact tool 1, the lower end portion of the protruding part 143B and the partition wall 152 will come into contact (touch) with each other.

The vibration isolating member 139A is sandwiched between the lower end portion of the protruding part 143A and the upper end portion of the protruding part 143B.

A lower end portion of the protruding part 143C, which is located in the groove part 141C, comes (stands) in contact with an upper end portion, which is an end portion of the vibration isolating member 139B, which is in the recessed part 142B, via the notched part 165, which is formed on the partition wall 155, at the lower end portion of the groove part 141C. The upper end portion of the vibration isolating member 139B comes (stands) in contact with a lower end portion of the protruding part 143C in the state where the upper end portion of the vibration isolating member 139B is inserted into the inside of the notched part 165 . An upper end portion of the projecting part 143C, which is located in the groove part 141C, is spaced from the partition wall 151 at an upper end portion of the groove part 141C. If the handle housing 3 rotates relative to the main body housing 2, e.g., due to vibration and/or torsion during operation of the impact tool 1, the upper end portion of the protruding part 143C and the partition wall 155 will come into contact (touch each other).

An upper end portion of the protruding part 143D, which is located in the groove part 141D, comes (stands) in contact with a lower end portion, which is the other end portion of the vibration isolating member 139B, which is located in the recessed part 142B, via the notched part 164 , which is formed on the partition wall 156, at an upper end portion of the groove part 141D. The lower end portion of the vibration isolating member 139B comes into contact with an upper end portion of the protruding part 143D in the state where the lower end portion of the vibration isolating member 139B is inserted inside the notched part 166 . A lower end portion of the protruding part 143D, which is located in the groove part 141D, is spaced from the partition wall 152 at a lower end portion of the groove part 141D. If the grip case 3 rotates relative to the main body case 2, for example, due to vibration or torsion during operation of the impact tool 1, the lower end portion of the projecting part 143D and the partition wall 152 will come into contact (touch each other).

The vibration isolating member 139B is sandwiched between the lower end portion of the protruding part 143C and the upper end portion of the protruding part 143D.

If 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 handle case 3 via the main body case 2 is suppressed by elastic deformation of the first vibration isolating portions 147 which are respectively in contact with the front Surfaces of the protruding parts 143 come (stand), and the elastic deformation of the second vibration-isolating portions 148, which respectively come (stand) in contact with the rear surfaces of the protruding parts 143, is damped. That is, due to the elastic deformation of the vibration isolating members 138 in the axial direction, the transmission of the vibration of the hammer case 6 in the axial direction parallel to the output rotation axis BX to the handle case 3 is damped (reduced).

If the hammer case 6 vibrates in the rotational direction centered on the output rotation axis BX, the vibration transmitted from the hammer case 6 to the handle case 3 via the main body case 2 is damped by elastic deformation of the vibration isolating members 139 each in contact with the end portions of the protruding parts 143 come (stand) in the direction of rotation. That is, due to the elastic deformation of the vibration isolating members 139 in the rotating direction, the transmission of the vibration of the hammer case 6 in the rotating direction centering on the output rotating axis BX to the handle case 3 is damped (reduced).

operation of the grinding tool

The operation of the striking tool 1 will be described below. For example, when a fastening work is performed on a work item, a socket used in the fastening work is mounted on a front end portion of the anvil 16 . After installing the socket on the anvil 16, the user grasps the side handle 7 with his left hand, grasps the handle portion 27 with his right hand, and manually actuates the trigger lever 116 with his index finger or middle finger of his right hand so that the trigger lever 116 moves moved behind. When the trigger lever 116 is manually operated (pressed) to move rearward, electric power is supplied from the battery pack 63 to the motor 10, and thereby the motor 10 is operated (energized) and the light assembly 18 is turned ON. In response to the operation (excitation) of the motor 10, the rotor 69 and the rotor shaft 70 rotate. When the rotor shaft 70 rotates, the rotational force of the rotor shaft 70 is transmitted to the planetary gears 89 via the first bevel gear 80, the second bevel gear 86 and the sun gear 88 . Since the planetary gears 89 mesh with the internal teeth of the internal gear 90 (which is non-rotatable relative to the housing), the planetary gears 89 revolve around the sun gear 88 while rotating. The planetary gears 89 are each supported in a rotatable manner by the spindle 14 via the pins 93 . Due to the rotation of the planetary gears 89, the spindle 14 rotates at a speed that is slower than the speed of the rotor shaft 70.

While the hammer projection parts 106 and the anvil projection parts 114 are in contact with each other and the spindle 14 rotates, the anvil 16 rotates together with the hammer 98 and the spindle 14. Due to the rotation of the anvil 16, the fastening work progresses.

However, when a load of a predetermined value or more acts on the anvil 16 due to the progress of the fastening work, the rotation of the anvil 16 and the hammer 98 temporarily stops. In this condition, in which the rotation of the hammer 98 is momentarily stopped but the spindle 14 continues to rotate relative to the anvil 16, the hammer 98 moves rearward. In response to the rearward movement of the hammer 98, the contact between the hammer projection parts 106 and the anvil projection parts 114 are released. Due to the elastic force of the first coil spring 100 and the second coil spring 101, the hammer 98, which has moved rearward, moves forward while rotating. Due to the forward movement of the hammer 98 while it is rotating, the anvil 16 is struck by the hammer 98 in the direction of rotation. As a result, the anvil 16 rotates about the output axis of rotation BX with a higher torque. Accordingly, a bolt or nut can be pulled out with a higher torque.

Here, if an excessively heavy load acts on the anvil shank part 113 during fastening work, there is a possibility that a portion of the anvil shank part 113 will break. In the embodiment, the breaking point portion 134 is provided on the anvil shank portion 113 . Accordingly, when an excessively heavy load is applied to the anvil shank portion 113, the anvil shank portion 113 is more prone to fracture (break off, fracture) at the frangible portion 134 than any other portion of the anvil shank portion 113, as referred to in FIG 13 described. Therefore, if the anvil shank portion 113 breaks at the frangible area 134 and the anvil shank portion 113 at the front of the frangible portion 134 moves forward relative to the hammer housing 6, the first rear surface 127 of the first groove portion 121 is caught by the retaining member 123. Accordingly, the broken-off area of the anvil shank part 113 on the front side of the predetermined breaking point area 134 is restrained (impeded, blocked) from detaching (falling out, separating) from the impact tool 1 .

Additionally or alternatively, the vibration of the hammer case 6 generated during fastening work is damped by the vibration damping mechanism 137. Therefore, the amount of vibration of the hammer case 6 transmitted to the handle case 3 via the main body case 2 is dampened (reduced). Accordingly, the occurrence of a decrease in work efficiency in the fastening work, the feeling of discomfort by the user gripping the grip case 3, or the like can be curbed. A vibration of the controller 11 accommodated in the controller accommodating portion 28 of the grip case 3 is also damped (reduced). Accordingly, the occurrence of operational errors of the controller 11 can be curbed (reduced).

effects

According to the embodiment described above, the impact tool 1 comprises the motor 10, the impact mechanism 15 which is driven by the motor 10, the anvil 16 which is impacted in the rotating direction by the impact mechanism 15, the hammer case 6 which accommodates the impact mechanism 15, and the anvil bearing 115. The striking mechanism 15 is rotatable about the output rotation axis BX extending in the front-rear direction. The anvil 16 has the anvil shank portion 113 disposed in front of the striking mechanism 15 and the anvil projection portions 114 projecting radially outward from the rear end portion of the anvil shank portion 113 . The anvil projection parts 114 are struck by the striking mechanism 15 in the rotating direction about the output rotating axis BX. The anvil bearing 115 is held by the hammer housing 6 and is disposed around the anvil shank portion 113 . A first groove part 121 is formed in the outer peripheral surface of the anvil shaft part 113 so as to encircle (encircle) the output rotation axis BX. A second groove part 122 is formed in the inner peripheral surface of the anvil bearing 115 so as to encircle (encircle) the output rotation axis BX. The striking tool 1 has the retaining component 123 which has the first area 124 which is arranged in the first groove part 121 and the second area 125 which is arranged in the second groove part 122 .

According to the configuration described above, since the retaining member 123 having the first portion 124 disposed inside (in contact with) the first groove portion 121 and the second portion 125 disposed inside (in contact with) the second groove portion 122 is provided, if the anvil shank portion 113 breaks during operation, the broken portion of the anvil shank portion 113 is caught by the retaining member 123 which is supported by the second groove portion 122. Accordingly, the broken portion of the anvil shank part 113 is restrained (blocked, prevented) from coming off (falling out, separating) from the hammer case 6 in the forward direction in the axial direction of the anvil shank part 113 . Accordingly, the broken portion of the anvil 16 can be restrained (blocked, prevented) from detaching (falling out) from the impact tool 1 .

In the embodiment, the retaining member 123 has a ring shape that encircles (encircles) the output rotation axis BX.

According to the configuration described above, if the anvil shaft part 113 breaks, the broken portion of the anvil shaft part 113 can be sufficiently caught by the retaining member 123 which is supported (held) by the second groove part 122 (is in contact with).

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

According to the configuration described above, the boundary (gap, space) between the inner surface of the first groove part 121 and the inner surface of the second groove part 122 is sealed by the O-ring. Accordingly, for example, a lubricant supplied to the striking mechanism 15 is prevented from flowing out (leaking) from (through) the boundary (gap, space) between the inner surface of the first groove part 121 and the inner surface of the second groove part 122 .

In the embodiment, the anvil shank portion 113 has the breaking point portion 134 whose section modulus is smaller than the section modulus of the anvil shank portion 113 in the first groove portion 121 . The breaking point portion 134 is arranged rearward of the first groove part 121 in the axial direction of the anvil shaft part 113 .

According to the configuration described above, if an excessively heavy load acts on the anvil shaft part 113 , the anvil shaft part 113 is more likely to be broken at the breaking point portion 134 . If the anvil shank part 113 breaks behind the first groove part 121, the first groove part 121 of the anvil shank part 113 is caught by the retaining member 123, which is supported (held) by the second groove part 122 (is in contact with it).

In the embodiment, the impact tool 1 has the third groove part 135 which is formed on the outer peripheral surface of the anvil shaft part 113 so as to encircle (encircle) the output rotation axis BX and which is arranged (located) rearward of the first groove part 121 . The diameter Db of the anvil shank portion 113 at the third groove portion 135 is smaller than the diameter Da of the anvil shank portion 113 at the first groove portion 121 . In other words, the predetermined breaking point area 134 is defined within or along the axial dimension of the third groove part 135 .

According to the above-described configuration, by forming the third groove part 135 in this way, the breaking point portion 134 can be formed in a simple manner.

In the embodiment, the inner surface of the first groove part 121 has the first front surface 126 which faces rearward, the first rear surface 127 which is arranged rearward of the first front surface 126 and faces forward, and the first peripheral surface 128 which is provided with a radially inner end portion of the first front surface 126 and a radially inner end portion of the first rear surface 127 with the first peripheral surface 128 facing radially outward. The inner surface of the second groove portion 122 has the second front surface 129 facing rearward and the second peripheral surface 131 connected to a radially outer end portion of the second front surface 129, the second peripheral surface 131 facing radially inward.

According to the configuration described above, since the first groove part 121 and the second groove part 122 are each suitably formed, if the anvil shank part 113 breaks at (along, inside) the breaking point area 134, the first groove part 121 of the anvil shank part 113 can be caught by the retaining member 123 , which is supported by the second groove portion 122.

In the embodiment, if the anvil shank portion 113 breaks at (along, within) the area of weakness 134, the retaining member 123 comes into contact with the first rear surface 127 and the second front surface 129.

According to the configuration described above, if the anvil shank portion 113 breaks at (along, within) the breaking point area 134, since the first back surface 127 of the first groove portion 121 is caught by the retaining member 123 which is supported by the second front surface 129 of the second groove portion 122 is stored, the broken portion of the anvil shank part 113 is restrained (blocked, prevented) from detaching (falling out, separating) from the hammer case 6 in the forward direction.

In the embodiment, the hammer case 6 has the bearing support surface 132 which comes into contact with (contacts) a front end portion of the anvil bearing 115 .

According to the configuration described above, since the front end portion of the anvil bearing 115 comes (stands) in contact with the bearing support surface 132 of the hammer case 6, the anvil bearing 115 is prevented from detaching (falling off, separating) from the hammer case 6 in the forward direction in of the axial direction of the anvil shank part 113 is restrained (blocked, hindered). Also, when the anvil shank portion 113 breaks, since the anvil bearing 115 does not come out (fall out) from the hammer case 6 in the forward direction due to the bearing bearing surface 132, the retaining member 123 supported (held) by the second groove portion 122 of the anvil bearing 115 comes out. neither does it come out (does not come off) from the hammer case 6 in the forward direction. Accordingly, if the anvil shank portion 113 breaks, the broken portion of the anvil shank portion 113 is prevented from detaching (falling out) from the hammer housing 6 in the forward direction due to the anvil shank portion 113 being caught by the retaining member 123 which is formed by the second groove portion 122 is stored, held back (blocked, impeded).

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

According to the configuration described above, the second groove part 122 is suitably formed on the inner peripheral surface of the anvil bearing 115, which is the slide bearing.

Other embodiments

In the embodiment described above, the retaining member 123 is an O-ring made of rubber. However, the retaining member 123 need not be an O-ring and may be an annular member made of synthetic resin (polymer) such as another type of elastomeric material or metal. Additionally, the retaining member 123 need not be ring-shaped and may be a snap ring, for example.

In the embodiment described above, within a plane perpendicular to the output rotation axis BX, the outer shape of the anvil shaft part 113 at the first groove part 121 is a circular shape, and the outer shape of the anvil shaft part 113 at the third groove part 135 is a circular shape. In addition, the diameter Db of the anvil shank portion 113 at the third groove portion 135 is smaller (less) than the diameter Da of the anvil shank portion 113 at the second groove portion 122. The outer shape of the anvil shank portion 113 at the frangible region 134 need not be circular. The section modulus of the breakneck portion 134 should be smaller (less) than the section modulus of the anvil shank portion 113 at the first groove portion 121 .

In the embodiment described above, the anvil bearing 115 is a plain bearing. Furthermore, the second groove part 122 is formed on the inner peripheral surface of the plain bearing. However, for example in an alternative embodiment, the anvil bearing 115 may comprise two ball bearings spaced in the front-to-back direction (i.e. in the axial direction of the anvil shank portion 113). The gap between the ball bearings can function as the second groove part 122 .

In the embodiment described above, the vibration isolating members 138 are made of rubber. However, the vibration damping members 138 may additionally or alternatively include springs, such as metal fall springs. Similarly, in the embodiment described above, the vibration damping members 138 are springs. However, the vibration damping members 139 may additionally or alternatively be formed from a rubber or other type of elastomeric material.

In the embodiment described above, the vibration isolating members 138 are respectively disposed in the groove portions 141 provided in the main body case 2 , and the vibration isolating members 139 are respectively disposed in the recessed portions 142 provided in the main body case 2 . In addition, the protruding parts 143 provided in the grip case 3 come into contact with the vibration isolating members 138 and the vibration isolating members 139 supported (held) by the main body case 2 . However, in an alternative embodiment, the vibration isolating members 138 and the vibration isolating members 139 may be supported (supported) by the grip case 3, and protruding parts provided on the main body case 2 may come (stand) in contact with the vibration isolating members 138 and the vibration isolating members 139. , which are supported (held) by the handle housing 3 .

In the embodiment described above, the vibration-isolating mechanism 137 has the vibration-isolating members 138 which attenuate (reduce) the transmission of vibration of the hammer case 6 in the axial direction parallel to the output rotation axis BX to the handle housing 3, and the vibration-isolating members 139 which prevent the transmission of the vibration of the hammer housing 6 in the rotation dampen (reduce) direction about the output axis of rotation BX to the handle housing 3. However, in an alternate embodiment, vibration damping mechanism 137 may include vibration damping members 138 but not vibration damping members 139. Additionally or alternatively, vibration damping mechanism 137 may include vibration damping members 139 but not vibration damping members 138.

In the embodiment described above, the impact tool 1 is an impact wrench. However, the present teachings can be applied to an impact wrench as well. The anvil of an impact wrench has an insertion hole into which a tool accessory is inserted and a chuck mechanism that holds (chucks) the tool accessory.

In the embodiment described above, the battery pack 63 serves as the power supply of the impact tool 1 and is mounted on the battery mounting part 9 . Alternatively, commercial power (AC power source) may be used as the power source of the impact tool 1 instead.

In the embodiment described above, the motor 10 is a brushless inner rotor type motor. However, the motor 10 may instead be an outer rotor type motor or a brush motor.

It is explicitly emphasized that all features disclosed in the description and/or the claims are to be regarded as separate and independent from each other for the purpose of original disclosure as well as for the purpose of limiting the claimed invention independently of the combinations of features in the embodiments and/or the claims should. It is explicitly stated that all indications of ranges or groups of units disclose every possible intermediate value or subgroup of units for the purpose of original disclosure as well as for the purpose of limiting the claimed invention, in particular also as a limit of a range indication.

Reference List

1

striking tool

2

main body casing

2L

left main body casing

2R

right main body casing

3

handle housing

3L

left handle housing

3R

right handle housing

4

motor housing

5

gear case

6

hammer case

7

side handle

8th

mute

9

battery mounting part

10

engine

11

steering

12

fan wheel

13

speed reduction mechanism

14

spindle

15

impact mechanism

16

anvil

17

trigger switch

18

light assembly

19

screw

20

main body part

21

protruding part

22

Transmission housing receiving part

23

motor housing connection part

24

tube part

25

rear wall part

26

screw

27

handle part

28

control receiving part

29

battery connector

30

coupling part

31

rear handle

32

upper handle

33

front handle

34

tube part

35

lower part of the wall

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 pipe part

47

second pipe part

48

opening

49

opening

50

screw

51

screw attachment

52

screw attachment

53

screw

54

screw attachment

55

handle part

56

base part

57

first base part

58

second base part

59

hinge

60

clamping mechanism

61

screw

62

wheel part

63

battery pack

64

terminal block

65

connector holder

66

Feather

67

damping component

68

stator

69

rotor

70

rotor shaft

71

stator core

72

insulator

73

Kitchen sink

74

busbar unit

75

rotor core

76

rotor magnet

77

sensor board

78

rotor bearings

79

rotor bearings

80

first bevel gear

81

control housing

82

air intake opening

83

air outlet opening

84

air intake opening

85

baffle plate

86

second bevel gear

87

planetary gear mechanism

88

sun gear

89

planet gear

90

internal gear

91

gear bearing

92

gear bearing

93

Pen

94

flange part

95

spindle shaft

96

protruding part

97

spindle bearing

98

hammer

99

Bullet

100

first coil spring

101

second coil spring

102

third coil spring

103

first washer

104

second washer

105

hammer body

106

hammer protrusion part

107

excepted part

108

Hole

109

Bullet

110

spindle groove

111

hammer groove

112

anvil exception part

113

anvil shaft part

114

anvil projection part

115

anvil bearing

116

pusher lever

117

switch main body

118

circuit board

119

light emitting device

120

light cover

121

first nut part

122

second nut part

123

retention component

124

first area

125

second area

126

first front surface

127

first back surface

128

first perimeter surface

129

second front surface

130

second back surface

131

second peripheral surface

132

bearing storage surface

133

sealing component

134

breaking point area

135

third groove part

136

large diameter part

137

vibration damping mechanism

138

Anti-vibration member (first anti-vibration member)

138A

anti-vibration component

138B

anti-vibration component

138C

anti-vibration component

138D

anti-vibration component

139

Anti-Vibration Component (Second Anti-Vibration Component)

139A

anti-vibration component

139B

anti-vibration component

140

outer peripheral surface

141

groove part

141A

groove part

141B

groove part

141C

groove part

141D

groove part

142

excepted part

142A

excepted part

142B

excepted part

143

protruding part

143A

protruding part

143B

protruding part

143C

protruding part

143D

protruding part

144

first storage surface

145

second storage surface

146

perimeter surface

147

first vibration damping area

148

second vibration damping area

149

third vibration damping area

151

partition wall

152

partition wall

153

partition wall

154

partition wall

155

partition wall

156

partition wall

163

notched part

164

notched part

165

notched part

166

notched part

181

ring spring

190

screw

460

cover

BX

output axis of rotation

CX

virtual axis

MX

motor axis of rotation

There

diameter

db

diameter

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• JP 6801571 B2 [0002]

Claims (10)

Impact tool (1), with a motor (10), an impact mechanism (15) rotatable about an output pivot axis (BX) extending in a front-rear direction and configured to be driven by the motor, an anvil (16) having an anvil shank portion (113) arranged in front of said striking mechanism in the front-rear direction and at least one anvil projection portion (114) projecting radially outward from a rear end portion of said anvil shank and configured thereto is to be struck by the striking mechanism in one direction of rotation and thereby rotated about the output axis of rotation, a hammer housing (6) which accommodates the striking mechanism, an anvil bearing (115) carried by the hammer housing and positioned around the anvil shank, a first groove part (121) formed on an outer peripheral surface of the anvil shaft part so as to encircle the output rotation axis, a second groove part (122) formed on an inner peripheral surface of the anvil bearing so as to encircle the output rotation axis, and a retaining member (123) having a first portion (124) located in said first groove portion and a second portion (125) located in said second groove portion. striking tool claim 1 wherein the retaining member (123) has an annular shape encircling the output pivot axis (BX). striking tool claim 1 or 2 wherein the retaining member (123) is an O-ring contacting an inner surface (126, 127, 128) of the first groove portion (121) and an inner surface (129, 130, 131) of the second groove portion (122). striking tool claim 3 wherein the O-ring (123) contacts both of a first peripheral surface (128) of the first groove portion (121) and a second peripheral surface (131) of the second groove portion (122). Striking tool after one of Claims 1 until 4 wherein the anvil shank portion (113) has a breaking point portion (134) located rearwardly of the first groove portion (121) in the front-rear direction, and the section modulus of the breaking point portion is smaller than the section modulus of the anvil shank portion at, along or within the first nut part is. striking tool claim 5 , having a third groove part (135) which is formed on the outer peripheral surface of the anvil shank part (113) rear of the first groove part (121) in the front-rear direction and encircles the output rotation axis (BX) at which the diameter of the anvil shank part at the third groove portion is smaller than the diameter of the anvil shank portion at the first groove portion, and the area of weakness (134) is defined within or along the third groove portion. striking tool claim 5 or 6 , wherein the inner surface of the first groove part (121) has a first front surface (126) facing rearward in the front-back direction, a first rear surface (127) which is arranged rearward of the first front surface and in facing forward in the front-to-back direction, and having a first peripheral surface (128) connected to a radially inner end portion of the first front surface and to a radially inner end portion of the first rear surface, and the first peripheral surface faces radially outward , and the inner surface of the second groove part (122) has a second front surface (129) facing rearward in the front-rear direction and a second peripheral surface (131) connected to a radially outer end portion of the second front surface connected, and the second peripheral surface faces radially inward. striking tool claim 7 , wherein the retaining member (123), the first groove part (121) and the second groove part (122) are configured so that the retaining member (123) is in contact with both the first rear surface (127) and the second front surface ( 129) in response to the anvil shank portion breaking at the frangible area (134). Striking tool after one of Claims 1 until 8th wherein the hammer housing (6) has a bearing support surface (132) which is in contact with a front end portion of the anvil bearing (115). Striking tool after one of Claims 1 until 9 , in which the anvil bearing (115) is a plain bearing.

Images