WO2022168710A1

WO2022168710A1 - Impact rotary tool

Info

Publication number: WO2022168710A1
Application number: PCT/JP2022/002913
Authority: WO
Inventors: 光政水野; 公孝小沢
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2021-02-08
Filing date: 2022-01-26
Publication date: 2022-08-11
Also published as: JP2022121272A

Abstract

The purpose of the present disclosure is to provide an impact rotary tool capable of reducing vibrations. The impact rotary tool (1) is equipped with a drive shaft (41), a hammer (42), a hammer claw (425) and an anvil (45). The drive shaft (41) rotates in the direction of rotation as a result of the drive unit (3). The hammer (42) engages the outer circumference of the drive shaft (41) so as to be capable of rotating in the direction of rotation and capable of moving in the axial direction of the drive shaft (41). The hammer claw (425) is provided to the hammer (42). The anvil (45) has an anvil claw (455) capable of engaging the hammer claw (425) in the direction of rotation. At least part of the hammer (42) and/or the anvil (45) is formed from a damping material which has higher damping properties than does steel.

Description

impact rotary tool

The present disclosure generally relates to impact rotary tools. More particularly, the present disclosure relates to an impact rotary tool having a configuration in which the hammer impacts the anvil.

Conventionally, impact rotary tools, which are portable tools for screw tightening called impact drivers and impact wrenches, have been used (see Patent Document 1, for example). The impact rotary tool has a hammer and an anvil, and the hammer collides with the anvil to apply an impact force in the rotational direction. As a result, the impact rotary tool can apply a strong screw-tightening torque to the screw or the like to be screw-tightened via the socket or the like attached to the attachment portion of the anvil.

　Conventional impact rotary tools generate vibration when the hammer and anvil collide. At this time, there is a problem that the vibration cannot be reduced and the impact rotary tool vibrates.

JP-A-2005-66807

An object of the present disclosure is to provide an impact rotary tool capable of reducing vibration.

An impact rotary tool according to one aspect of the present disclosure includes a drive shaft, a hammer, a hammer claw, and an anvil. The drive shaft is rotated in the direction of rotation by the drive section. The hammer is fitted on the outer periphery of the drive shaft so as to be movable in the axial direction of the drive shaft and rotatable in the rotational direction. A hammer claw is provided on the hammer. The anvil has an anvil pawl rotationally engageable with the hammer pawl. At least a portion of at least one of the hammer and the anvil is made of a damping material having damping properties higher than steel.

1 is an external perspective view of an impact rotary tool according to an embodiment of the present disclosure; FIG. FIG. 2 is a cross-sectional view of main parts of an impact rotary tool according to an embodiment of the present disclosure; FIG. 3A is an external perspective view of the same hammer. FIG. 3B is an external perspective view of the same hammer from another viewpoint. FIG. 4 is an external perspective view of the anvil same as the above. 5A to 5E are external views explaining a portion of the anvil same as the above which is formed of a damping material. FIGS. 6A to 6E are external views for explaining portions of the same hammer formed of a damping material.

(embodiment)
(1) Overview An overview of an impact rotary tool 1 according to one embodiment will be described below with reference to FIGS. 1 and 2. FIG.

The impact rotary tool 1 of this embodiment includes a drive shaft 41, a hammer 42, a hammer claw 425, and an anvil 45, as shown in FIGS. Assume a case where a worker uses the impact rotary tool 1 for a tightening work of tightening a tightening part (screw, bolt, nut, etc.) to a tightening object (electrical appliance, furniture, etc.). Moreover, the impact rotary tool 1 may be used for a removal work in which a worker loosens a tightened part from a tightened object.

The drive shaft 41 is rotated in the direction of rotation by the drive unit 3 .

The hammer 42 is fitted on the outer periphery of the drive shaft 41 so as to be movable in the axial direction of the drive shaft 41 and rotatable in the rotational direction. A hammer claw 425 is provided on the hammer 42 .

The anvil 45 has an anvil claw 455 that can be engaged with the hammer claw 425 in the rotational direction of the drive shaft 41 . Since the hammer 42 rotates in the rotational direction of the drive shaft 41 while moving forward, the hammer 42 imparts a rotational impact force to the anvil claw 455 when the hammer claw 425 engages the anvil claw 455 in the rotational direction. At the same time, the hammer claw 425 collides with the anvil claw 455, causing vibration.

At least a portion of at least one of the hammer 42 and the anvil 45 is made of a damping material with higher damping properties than steel. The term "vibration damping property" as used herein refers to the property of converting vibrational energy entering the material from the outside into heat energy and absorbing it. In other words, "high damping property" means that the damping rate of vibration entering the material from the outside is high. Therefore, the vibration generated when the hammer claw 425 collides with the anvil claw 455 is absorbed and attenuated by the damping material when transmitted through the portion formed of the damping material.

Therefore, the impact rotary tool 1 of this embodiment has the advantage of being able to reduce the vibration generated when the hammer claw 425 collides with the anvil claw 455 .

(2) Details (2-1) Overall Configuration The detailed configuration of the impact rotary tool 1 of the present embodiment will be described below with reference to FIGS. 1 to 6. FIG.

In the following description, the direction in which the hammer 42 and the anvil 45 are aligned (the X direction in FIG. 2) is defined as the front-rear direction, and the anvil 45 side as viewed from the hammer 42 is defined as the front. The 42 side is defined as rear. Further, in the following description, the direction in which the second portion 22 and the grip portion 23 are arranged is defined as the vertical direction (the Y direction in FIG. 2), and the second portion 22 side as viewed from the grip portion 23 , and the grip portion 23 side as viewed from the second portion 22 is defined as the bottom. However, these regulations are not meant to define the usage direction of the impact rotary tool 1 .

The impact rotary tool 1 of this embodiment is a portable power tool. As shown in FIG. 2 , the impact rotary tool 1 includes a housing 2 , a drive section 3 , a transmission mechanism 4 , a drive circuit block 81 , a control section 82 and an operation section 83 .

(2-2) Housing The impact rotary tool 1 further includes a housing 2 that accommodates at least a portion of the drive shaft 41 , hammer 42 or anvil 45 . The housing 2 of this embodiment accommodates the drive section 3, the transmission mechanism 4, the drive circuit block 81, and the control section 82. As shown in FIG. As shown in FIGS. 1 and 2 , the housing 2 has a first portion 21 , a second portion 22 , a grip portion 23 and a battery mounting portion 24 .

(First part)
The first portion 21 has a first bottom portion 211 and a first side portion 212 . The shape of the first bottom portion 211 is disc-shaped. The thickness direction of the first bottom portion 211 extends along the front-rear direction. The first bottom portion 211 has a housing through hole 2110 formed in the front-rear direction. A housing through-hole 2110 is provided in the center of the first bottom portion 211 . A power transmission portion 452 of the anvil 45 , which will be described later, is passed through the housing through hole 2110 .

The shape of the first side portion 212 is cylindrical. More specifically, the shape of the first side portion 212 is cylindrical. The first side portion 212 protrudes from the first bottom portion 211 . More specifically, the first side portion 212 protrudes from the peripheral portion of the first bottom portion 211 . The first side portion 212 protrudes rearward from the first bottom portion 211 .

(Second part)
The second portion 22 has a second bottom portion 221 and a second side portion 222 . The shape of the second bottom portion 221 is disc-shaped. The thickness direction of the second bottom portion 221 extends along the front-rear direction.

The shape of the second side portion 222 is substantially cylindrical. More specifically, the shape of the second side portion 222 is generally cylindrical. The second side portion 222 protrudes from the second bottom portion 221 . More specifically, the second side portion 222 protrudes from the peripheral portion of the second bottom portion 221 . The second side portion 222 protrudes forward from the second bottom portion 221 .

The second part 22 accommodates the first part 21 . More specifically, the inner surface of the second side portion 222 is in close contact with the outer surface of the first side portion 212 , and the front end of the second side portion 222 is in contact with the peripheral edge of the first bottom portion 211 . The part 22 accommodates the first part 21 . Also, since the front-rear dimension of the second side portion 222 is longer than the front-rear dimension of the first side portion 212 , the rear end portion of the first side portion 212 does not touch the peripheral portion of the second bottom portion 221 . Therefore, the rear portion of the second side portion 222 does not adhere to the outer surface of the first side portion 212 .

A plurality of ventilation holes 223 are provided in the second side portion 222 of the second portion 22 . More specifically, the second part 22 has a plurality of ventilation holes 223 in a second side portion 222 that is not in close contact with the outer surface of the first side portion 212 .

(Grip part)
The grip portion 23 protrudes from the second portion 22 . More specifically, the grip portion 23 protrudes downward from the second portion 22 . A worker can grip the grip portion 23 and perform operations such as screw tightening.

(applied part)
The shape of the battery mounting portion 24 is rectangular parallelepiped. Battery mounting portion 24 is connected to the lower end of grip portion 23 . A rechargeable battery pack B<b>1 is detachably attached to the battery mounting portion 24 . The impact rotary tool 1 operates using the battery pack B1 as a power source. That is, the battery pack B<b>1 is a power source that supplies a current for driving the drive unit 3 . Battery pack B<b>1 is not a component of impact rotary tool 1 . However, the impact rotary tool 1 may include the battery pack B1. The battery pack B1 includes an assembled battery configured by connecting a plurality of secondary batteries (for example, lithium ion batteries) in series, and a case accommodating the assembled battery.

(2-3) Drive Section As shown in FIG. 2, the drive section 3 is not accommodated in the first portion 21 of the housing 2, but is accommodated in the rear portion of the second portion 22. As shown in FIG. The drive unit 3 is, for example, a brushless motor. The drive unit 3 includes a rotor 31 having a rotating shaft 311 and permanent magnets, and a stator 32 having coils. Rotor 31 rotates relative to stator 32 due to electromagnetic interaction between the permanent magnets and the coils.

Also, the drive unit 3 is a servomotor. The torque and rotational speed of the drive section 3 change according to control by the control section 82 (servo driver). More specifically, the control unit 82 controls the operation of the drive unit 3 through feedback control that controls the torque and rotational speed of the drive unit 3 to approach target values.

(2-4) Transmission Mechanism As shown in FIG. 2, the transmission mechanism 4 is housed in the first portion 21 of the housing 2 . The transmission mechanism 4 has an impact mechanism 40 . The impact rotary tool 1 of this embodiment is an electric impact driver that performs a tightening operation while performing an impact operation by an impact mechanism 40 . The impact mechanism 40 generates an impact force based on the power of the drive unit 3 in the impact operation, and the impact force acts on the tip tool 62 .

The transmission mechanism 4 has a planetary gear mechanism 48 in addition to the impact mechanism 40 . The impact mechanism 40 includes a drive shaft 41 , a hammer 42 , an elastic member 43 , an anvil 45 and two first spheres 49 .

The planetary gear mechanism 48 converts the rotation speed and torque of the rotating shaft 311 of the drive unit 3 into the rotation speed and torque required for the screw driving operation. The planetary gear mechanism 48 is a reduction gear. Torque of the rotating shaft 311 of the drive unit 3 is transmitted to the drive shaft 41 via the planetary gear mechanism 48 . Torque of the drive shaft 41 is transmitted to the hammer 42 . This causes the hammer 42 to rotate. Torque of hammer 42 is transmitted to anvil 45 . This causes the anvil 45 to rotate. The drive shaft 41 is arranged between the drive portion 3 and the anvil 45 .

The hammer 42 moves relative to the anvil 45 and receives power from the drive unit 3 to apply a striking force to the anvil 45 . 3A is an external perspective view of the hammer 42 seen from the front side, and FIG. 3B is an external perspective view of the hammer 42 seen from the rear side. As shown in FIGS. 2 and 3A, hammer 42 includes a hammer body 420 and two hammer pawls 425 . The shape of the hammer body 420 is cylindrical, as shown in FIGS. 3A and 3B. The hammer body 420 has a front surface 424 of the hammer body 420 on the anvil 45 side (front side) and a rear surface 426 of the hammer body 420 on the side of the drive unit 3 (rear side).

The hammer body 420 has a hammer through hole 421 through which the drive shaft 41 is passed. More specifically, the hammer through-hole 421 is fitted to the outer circumference of the drive shaft 41 so as to be movable in the axial direction of the drive shaft 41 and rotatable in the rotational direction.

The two hammer claws 425 protrude from the hammer front surface 424. The two hammer claws 425 are arranged at approximately equal intervals in the circumferential direction of the hammer body 420 . When viewed from the front side of the hammer 42, each of the two hammer claws 425 has a fan shape. The two hammer claws 425 each have two hammer claw side surfaces 4250 that are circumferential side surfaces of the hammer body 420 .

The hammer rear surface 426 has a hammer recess 427 . The shape of the hammer recess 427 is an annular shape that extends in the circumferential direction of the hammer body 420 .

The hammer main body 420 has two hammer side grooves 423 on the inner peripheral surface of the hammer through hole 421 . As shown in FIG. 1, the drive shaft 41 has two drive shaft side grooves 413 on its outer peripheral surface. The two drive shaft side grooves 413 may be connected. Two first spheres 49 are sandwiched between the two hammer-side grooves 423 and the two drive-shaft-side grooves 413 . The two hammer-side grooves 423, the two drive-shaft-side grooves 413, and the two first spherical bodies 49 constitute a cam mechanism. While the two first spherical bodies 49 move in the hammer-side groove portion 423 and the drive-shaft-side groove portion 413, the hammer 42 can move in the axial direction (front-rear direction) of the drive shaft 41 with respect to the drive shaft 41, Moreover, it is rotatable with respect to the drive shaft 41 . As the hammer 42 moves toward or away from the power transmission section 452 along the axial direction of the drive shaft 41 , the hammer 42 rotates with respect to the drive shaft 41 .

The anvil 45 includes an anvil body 450, a mounting portion 451, an anvil shaft 453, and two anvil claws 455, as shown in FIGS. The anvil body 450 has an annular shape. The two anvil claws 455 protrude from the anvil body 450 in the radial direction of the anvil body 450 . The shape of the two anvil claws 455 is a rectangular parallelepiped. More specifically, the shape of the two anvil claws 455 is a rectangular parallelepiped having an anvil recess 4551 recessed on the front side (X direction side in FIG. 4) of the radial side surface of the anvil main body 450 . Two anvil pawls 455 are engageable with hammer pawls 425 in the rotational direction of hammer 42 . More specifically, the two anvil claws 455 each have two anvil claw side surfaces 4550 that are circumferential sides of the hammer body 420, and the anvil claw side surfaces 4550 engage the hammer claw side surfaces 4250 in the rotational direction. do.

The power transmission part 452 is formed between the anvil claw 455 and the mounting part 451 and is composed of an anvil shaft 453 and an anvil main body 450 . The shape of the anvil shaft 453 is cylindrical. Also, the anvil shaft 453 protrudes forward from the anvil main body 450 (the X direction in FIGS. 2 and 4). The anvil 45 faces the hammer body 420 in the front-rear direction. The anvil body 450 and two anvil claws 455 are housed in the first portion 21 of the housing 2 . The power transmission portion 452 is passed through a housing through hole 2110 provided in the housing 2 , and the mounting portion 451 is exposed to the outside of the housing 2 . The power transmission portion 452 transmits impact or vibration from the two anvil claws 455 to the mounting portion 451 .

The mounting part 451 mounts the tip tool 62 (see FIG. 1). In this embodiment, the tip tool 62 is connected to the power transmission part 452 via the chuck 61 (see FIG. 1). The anvil 45 receives torque from the drive unit 3 and rotates together with the chuck 61 and the tip tool 62 .

The chuck 61 and the tip tool 62 are not components of the impact rotary tool 1. However, the impact rotary tool 1 may include at least one of the chuck 61 and the tip tool 62 . Alternatively, the tip tool 62 may be directly connected to the power transmission portion 452 .

The tip tool 62 is, for example, a driver bit. The tip tool 62 is fitted with a screw (bolt, screw, or the like) to be worked. By rotating the tip tool 62 in a state where the tip tool 62 is engaged with the screw, it is possible to tighten or loosen the screw.

The elastic member 43 is sandwiched between the hammer recess 427 and the planetary gear mechanism 48 . The elastic member 43 of this embodiment is a conical coil spring. The impact mechanism 40 further includes a plurality of (two in FIG. 2) second spheres 50 sandwiched between the hammer 42 and the elastic member 43 and a ring 51 . Thereby, the hammer 42 is rotatable with respect to the elastic member 43 . The hammer 42 receives forward force from the elastic member 43 .

When the impact mechanism 40 is not performing an impact operation, the two hammer claws 425 of the hammer 42 and the two anvil claws 455 of the anvil 45 are in contact with each other in the rotational direction of the drive shaft 41 while the hammer 42 and the anvil 45 are in contact with each other. rotate together. Therefore, at this time, the drive shaft 41, the hammer 42, the anvil 45, and the tip tool 62 rotate together.

The impact mechanism 40 performs an impact operation when a torque condition regarding the magnitude of torque applied to the anvil 45 (hereinafter referred to as load torque) is satisfied. The impact operation is an operation in which the hammer 42 applies a striking force to the anvil 45 . In this embodiment, the torque condition is that the load torque is equal to or greater than a predetermined value. That is, as the load torque increases, the component of the force generated between the hammer 42 and the anvil 45 that causes the hammer 42 to move backward also increases. When the load torque reaches or exceeds a predetermined value, the hammer 42 retreats while compressing the elastic member 43 . Then, the hammer 42 rotates while the two hammer claws 425 of the hammer 42 get over the two anvil claws 455 of the anvil 45 by retreating the hammer 42 . After that, the hammer 42 moves forward by receiving the restoring force from the elastic member 43 . Then, when the drive shaft 41 rotates approximately halfway, the two hammer claws 425 of the hammer 42 collide with the anvil claw side surfaces 4550 of the two anvil claws 455 of the anvil 45 . In the impact mechanism 40, the two hammer pawls 425 of the hammer 42 collide with the two anvil pawls 455 of the anvil 45 each time the drive shaft 41 rotates approximately halfway. That is, the hammer 42 applies an impact (rotational impact force) to the anvil 45 each time the drive shaft 41 rotates approximately halfway.

Thus, in the impact mechanism 40, collisions between the hammer 42 and the anvil 45 occur repeatedly. The torque due to this collision allows the tightening parts to be tightened more strongly than when there is no collision.

(2-5) Holding Base As shown in FIG. 2, the impact rotary tool 1 further includes a holding base 11. As shown in FIG. The holding table 11 is housed in the housing 2 . The holding table 11 is held by the first portion 21 of the housing 2 .

The shape of the holding table 11 is a hollow columnar shape. The holding base 11 holds a planetary gear mechanism 48 inside thereof. That is, the holding base 11 rotatably holds the gears of the planetary gear mechanism 48 . A rotating shaft 311 of the drive unit 3 is inserted into a through hole formed in the rear surface of the holding base 11 and connected to the planetary gear mechanism 48 . A drive shaft 41 protrudes from the front surface of the holding table 11 .

(2-6) Spacer As shown in FIG. 2, the impact rotary tool 1 further includes a spacer 46. As shown in FIG. The spacer 46 has an annular shape. A spacer 46 is attached to the rear end of the first portion 21 of the housing 2 . Spacer 46 is arranged between first portion 21 and two anvil claws 455 of anvil 45 .

(2-7) Bearings As shown in FIG. 2, the impact rotary tool 1 includes a first bearing 71, a second bearing 72, a third bearing 73, a fourth bearing 74, and a fifth bearing 75. Prepare more.

The first bearing 71 is held by the first portion 21 of the housing 2 . The first bearing 71 is arranged inside the first portion 21 . The first bearing 71 rotatably supports the power transmission portion 452 .

The second bearing 72 is held by the holding base 11 . The second bearing 72 is attached to the front surface of the holding base 11 . The second bearing 72 rotatably supports the drive shaft 41 .

The third bearing 73 is held by the holding base 11 . The third bearing 73 is arranged inside the holding base 11 . The third bearing 73 rotatably supports the drive shaft 41 .

The fourth bearing 74 is held by the holding table 11 . The fourth bearing 74 is attached to the rear surface of the holding base 11 . The fourth bearing 74 rotatably supports the rotating shaft 311 of the driving section 3 .

The fifth bearing 75 is held by the second portion 22 of the housing 2 . The fifth bearing 75 rotatably supports the rotating shaft 311 of the driving section 3 .

(2-8) Operation Portion As shown in FIG. 2, the operation portion 83 protrudes from the grip portion 23. As shown in FIG. The operating portion 83 receives an operation for controlling the rotation of the rotating shaft 311 of the drive portion 3 . The drive unit 3 can be turned on and off by pulling the operation unit 83 . Further, the rotation speed of the rotating shaft 311 can be adjusted by the amount of retraction of the operation of pulling the operation portion 83 . The rotation speed of the rotary shaft 311 increases as the retraction amount increases.

(2-9) Control Unit The control unit 82 rotates or stops the rotating shaft 311 and controls the rotation speed of the rotating shaft 311 according to the amount of pulling of the operation unit 83 .

The control unit 82 includes, for example, a microcontroller. The control section 82 can change the rotational speeds of the power transmission section 452 and the tip tool 62 by changing the rotational speed of the rotating shaft 311 . The control unit 82 changes the rotation speed of the rotating shaft 311 by changing the electric power supplied to the drive unit 3, for example.

(2-10) Drive Circuit Block As shown in FIG. 2, the drive circuit block 81 is arranged behind the drive section 3 . Drive circuit block 81 includes a substrate 810 and a plurality of electronic components mounted on substrate 810 . A plurality of electronic components includes a plurality of power elements forming an inverter circuit. Each power element is, for example, a FET (Field Effect Transistor) element.

The control unit 82 controls the driving unit 3 via the driving circuit block 81. That is, the control unit 82 controls the power supplied to the driving unit 3 via multiple FET elements (inverter circuits) by switching the multiple FET elements of the driving circuit block 81 on and off.

(2-11) Fan As shown in FIG. 2 , the impact rotary tool 1 further includes a fan 14 . Fan 14 is housed in second portion 22 of housing 2 . The fan 14 is arranged between the driving section 3 and the holding base 11 .

The fan 14 is connected to the rotating shaft 311 of the drive unit 3. The fan 14 rotates together with the rotating shaft 311 . The fan 14 generates wind that flows forward. Thereby, the fan 14 air-cools the internal space of the housing 2 .

(2-12) Vibration Damping Material However, vibration occurs when the hammer 42 and the anvil 45 collide repeatedly. Therefore, in order to reduce the vibration, at least a portion of at least one of the hammer 42 and the anvil 45 is made of a damping material having damping properties higher than that of steel. A damping material with high damping properties is a material that has a high ability to convert vibration energy entering the material from the outside into heat energy and absorb it. In other words, a damping material with high damping properties is a material with a high damping rate for vibrations coming from the outside. Therefore, the vibration generated when the hammer claw 425 collides with the anvil claw 455 is absorbed and attenuated by the damping material when transmitted through the portion formed of the damping material.

In this embodiment, of the hammer 42 and the anvil 45, at least part of the anvil 45 is made of a damping material. More specifically, at least a portion of the anvil claw 455 and at least a portion of the power transmission portion 452 are made of damping material. Specifically, as shown in FIG. 5A, the entire anvil claw 455 and the entire power transmission portion 452 are made of a damping material. FIG. 5A is an external view of the anvil 45, in which portions formed of damping material are indicated by dots. Therefore, the vibration generated when the hammer claw 425 collides with the anvil claw 455 is absorbed and attenuated by the damping material when it is transmitted to the mounting portion 451 via the anvil claw 455 and the power transmission portion 452 . As a result, it is possible to reduce the noise generated when the tip tool 62 collides with the fastening fixture due to the vibration of the mounting portion 451 . 5B, the entire anvil claw 455 and the rear portion of the power transmission portion 452 may be made of a damping material.

In the present embodiment, of the hammer 42 and the anvil 45, at least part of the anvil 45 may be made of the damping material, and at least part of the power transmission portion 452 of the anvil 45 may be made of the damping material. may be formed of In this case, the anvil claw 455 can be made of a hard metal such as steel to prevent the anvil claw 455 from wearing due to engagement with the hammer claw 425 . For example, the rear portion of anvil shaft 453 may be formed of damping material, as shown in the dotted portion of FIG. 5C.

Similarly, in the present embodiment, of the hammer 42 and the anvil 45, at least a portion of the anvil 45 only needs to be made of a damping material, and at least a portion of the anvil claw 455 of the anvil 45 is a damping material. It may be made of a vibrating material. For example, as shown in the dotted portion of FIG. 5D, the entire anvil claw 455 may be made of damping material. 5E, the anvil claw 455 includes two anvil claw side portions 4552 having anvil claw side surfaces 4550 and an anvil claw center sandwiched between the two anvil claw side portions 4552 in the circumferential direction of the anvil main body 450. and a part 4553 . In this case, the anvil claw central portion 4553 of the anvil 45 may be made of a damping material. FIG. 5E is an external view of the anvil 45 as viewed from the front, and the portions formed of the damping material are indicated by dots.

A damping alloy is used as the damping material in this embodiment. Specifically, the damping material of this embodiment is an alloy containing at least iron and aluminum. A damping alloy is an alloy that has the property of damping vibration by converting externally applied vibration energy into heat energy and absorbing it.

Also, at least part of the anvil claw 455 is preferably hardened. In this embodiment, the anvil claw side surface 4550 is hardened. As a result, the strength of the anvil claw side surface 4550 can be increased, and wear of the anvil claw side surface 4550 due to engagement with the hammer claw 425 can be prevented. For example, the hardening treatment is a nitriding treatment that increases hardness by forming a carbonitride or nitride layer on the surface of the anvil claw side surface 4550 . Alternatively, the surface of the anvil claw side surface 4550 itself may be quenched to have a high-hardness texture, or may be surface-protected to coat the surface of the anvil claw side surface 4550 with a high-hardness substance.

(2-13) Advantages In the impact rotary tool 1 of the present embodiment, both the anvil claw 455 and the power transmission part 452 are made of a vibration damping material, and the vibration damping material absorbs vibration to Vibration generation of the rotating tool 1 can be suppressed. Therefore, there is an advantage of providing an impact rotary tool 1 that can reduce vibration.

(3) Modifications The above-described embodiment is merely one of various embodiments of the present disclosure. The above-described embodiments can be modified in various ways according to design and the like as long as the object of the present disclosure can be achieved. The following modified examples may be implemented in combination as appropriate.

In the above-described embodiment, of the hammer 42 and the anvil 45, at least part of the anvil 45 is made of a damping material. However, of the hammer 42 and the anvil 45, at least part of the hammer 42 may be made of the damping material. For example, as shown in FIG. 6A, the entire hammer 42 may be made of damping material. FIG. 6A is an external view of the hammer 42, in which portions made of damping material are indicated by dots. 6B, the hammer body 420 may be made of a damping material, and as shown in the dotted portion of FIG. 6C, the hammer claw 425 may be made of a damping material. good too. Further, the hammer 42 has a hammer connection portion 428 that connects the hammer body 420 with the hammer claw 425, and as shown in the dot portion of FIG. may have been As shown in FIG. 6E , the hammer claw 425 includes two hammer claw side portions 4251 having hammer claw side surfaces 4250 and a hammer claw central portion sandwiched between the two hammer claw side portions 4251 in the circumferential direction of the hammer main body 420 . and a part 4252 . In this case, the hammer claw central portion 4252 of the hammer 42 may be made of a damping material. FIG. 6E is an external view of the hammer 42 viewed from the front, and the portion formed of the damping material is indicated by dots.

In one aspect of the present embodiment, at least part of the housing 2 may be made of a damping material. In this case, vibrations transmitted through the housing 2 can be damped. For example, the entire first portion 21 may be made of a damping material, or the entire second portion 22 may be made of a damping material. Also, part of the first portion 21 may be made of a damping material, and part of the second portion 22 may be made of a damping material. Furthermore, at least part of the first part 21 and at least part of the second part 22 may be made of a damping material. In this case, at least part of at least one of the hammer 42 and the anvil 45 does not necessarily have to be made of a damping material. Therefore, both the hammer 42 and the anvil 45 may not be made of damping material, and at least part of the housing 2 may be made of damping material.

In addition, the damping material according to one aspect may be a material having high damping properties, and may be a twin-crystal damping alloy. A twin-type damping alloy is an alloy that absorbs vibration energy through static hysteresis and stress relaxation associated with the movement of the boundary between the twin crystal and the parent phase. A twin-type damping alloy is, for example, an alloy containing at least iron and copper.

Also, the damping material according to one aspect may be a ferromagnetic damping alloy. A ferromagnetic damping alloy is an alloy that absorbs vibration energy due to the magnetic and mechanical static hysteresis of magnetic domain walls that move irreversibly when a ferromagnetic body receives alternating stress. For example, a ferromagnetic damping alloy is an alloy containing at least iron and chromium.

(summary)
As described above, the impact rotary tool (1) according to the first aspect includes a drive shaft (41), a hammer (42), a hammer claw (425), and an anvil (45). The drive shaft (41) is rotated in the direction of rotation by the drive (3). The hammer (42) is fitted to the outer circumference of the drive shaft (41) so as to be movable in the axial direction of the drive shaft (41) and rotatable in the rotational direction. A hammer claw (425) is provided on the hammer (42). Anvil (45) has an anvil pawl (455) rotationally engageable with hammer pawl (425). At least a portion of at least one of the hammer (42) and the anvil (45) is made of a damping material that is more damping than steel.

According to this aspect, there is an advantage that the vibration generated when the hammer claw (425) collides with the anvil claw (455) can be reduced.

In the impact rotary tool (1) according to the second aspect, in the first aspect, at least part of the anvil (45) is made of a damping material.

According to this aspect, there is an advantage that the vibration transmitted by at least part of the anvil (45) can be reduced.

In the impact rotary tool (1) according to the third aspect, in the second aspect, the anvil (45) further has a mounting portion (451) and a power transmission portion (452). The mounting part (451) mounts the tip tool (62). A power transmission portion (452) is formed between the anvil pawl (455) and the mounting portion (451). At least part of the power transmission portion (452) is made of a damping material.

According to this aspect, there is an advantage that the vibration transmitted by the power transmission section (452) can be reduced.

In the impact rotary tool (1) according to the fourth aspect, in the third aspect, both at least part of the anvil claw (455) and at least part of the power transmission part (452) are made of a damping material is formed by

According to this aspect, there is an advantage that the vibration transmitted by both the power transmission section (452) and the anvil claw (455) can be reduced.

In the impact rotary tool (1) according to the fifth aspect, in the second aspect, at least part of the anvil claw (455) is made of a damping material.

According to this aspect, there is an advantage that the vibration transmitted by the anvil claw (455) can be reduced.

In the impact rotary tool (1) according to the sixth aspect, in any one of the first to fifth aspects, at least part of the anvil claw (455) is hardened.

According to this aspect, there is an advantage that vibration generated when the hammer claw (425) collides with the anvil claw (455) can be reduced while maintaining the strength of the anvil claw (455).

In the impact rotary tool (1) according to the seventh aspect, in the first aspect, at least part of the hammer (42) is made of a damping material.

According to this aspect, there is an advantage that the vibration transmitted by at least part of the hammer (42) can be reduced.

An impact rotary tool (1) according to an eighth aspect, in the first aspect, further comprises a housing (2) housing at least part of the drive shaft (41), the hammer (42), or the anvil (45). . At least part of the housing (2) is made of damping material.

According to this aspect, there is an advantage that vibration transmitted by at least a part of the housing (2) can be reduced.

In the impact rotary tool (1) according to the ninth aspect, in any one of the first to eighth aspects, the damping material is an alloy containing at least iron and aluminum.

According to this aspect, using an alloy material containing iron has the advantage of ensuring durability and facilitating processing.

In the impact rotary tool (1) according to the tenth aspect, in any one of the first to eighth aspects, the damping material is a twinned damping alloy.

According to this aspect, there is an advantage that an alloy that absorbs vibrational energy can be used as a damping material due to the static history and stress relaxation associated with the movement of the boundary between the twin crystal and the parent phase.

In the impact rotary tool (1) according to the eleventh aspect, in the tenth aspect, the twin-type damping alloy is an alloy containing at least iron and copper.

In the impact rotary tool (1) according to the twelfth aspect, in any one of the first to eighth aspects, the damping material is a ferromagnetic damping alloy.

According to this aspect, there is an advantage that an alloy that absorbs vibration energy can be used as a damping material due to its magnetic and mechanical static history.

In the impact rotary tool (1) according to the thirteenth aspect, in the twelfth aspect, the ferromagnetic damping alloy is an alloy containing at least iron and chromium.

The impact rotary tool (1) according to the fourteenth aspect comprises a drive shaft (41), a hammer (42), a hammer claw (425) and an anvil (45). The drive shaft (41) is rotated in the direction of rotation by the drive (3). The hammer (42) is fitted to the outer circumference of the drive shaft (41) so as to be movable in the axial direction of the drive shaft (41) and rotatable in the rotational direction. A hammer claw (425) is provided on the hammer (42). Anvil (45) has an anvil pawl (455) rotationally engageable with hammer pawl (425). At least a portion of the hammer (42) is made of damping material.

An impact rotary tool (1) according to a fifteenth aspect comprises a drive shaft (41), a hammer (42), a hammer claw (425), an anvil (45) and a housing (2). The drive shaft (41) is rotated in the direction of rotation by the drive (3). The hammer (42) is fitted to the outer circumference of the drive shaft (41) so as to be movable in the axial direction of the drive shaft (41) and rotatable in the rotational direction. A hammer claw (425) is provided on the hammer (42). Anvil (45) has an anvil pawl (455) rotationally engageable with hammer pawl (425). A housing (2) houses at least part of the drive shaft (41), hammer (42) or anvil (45). At least part of the housing (2) is made of damping material.

The configurations according to the second to fifteenth aspects are not essential to the rotary impact tool (1) according to the first aspect, and can be omitted as appropriate.

1 impact rotary tool 2 housing 3 drive unit 41 drive shaft 42 hammer 425 hammer claw 45 anvil 451 mounting portion 452 power transmission unit 455 anvil claw 62 tip tool

Claims

a drive shaft rotated in a rotational direction by a drive unit;
a hammer fitted to the outer periphery of the drive shaft so as to be movable in the axial direction of the drive shaft and rotatable in the rotational direction;
a hammer claw provided on the hammer;
an anvil having an anvil claw engageable with the hammer claw in the rotational direction;
with
An impact rotary tool, wherein at least a portion of at least one of the hammer and the anvil is made of a damping material having a damping property higher than that of steel.
The impact rotary tool according to claim 1, wherein at least a portion of said anvil is formed of said damping material.
The anvil further includes a mounting portion for mounting a tip tool, and a power transmission portion formed between the anvil claw and the mounting portion,
The impact rotary tool according to claim 2, wherein at least part of the power transmission portion is made of the damping material.
The impact rotary tool according to claim 3, wherein both at least part of the anvil claw and at least part of the power transmission part are made of the damping material.
The impact rotary tool according to claim 2, wherein at least part of the anvil claw is made of the damping material.
The impact rotary tool according to any one of claims 1 to 5, wherein at least part of the anvil claw is hardened.
The impact rotary tool according to claim 1, wherein at least part of the hammer is made of the damping material.
further comprising a housing that houses at least a portion of the drive shaft, the hammer, or the anvil;
The impact rotary tool according to claim 1, wherein at least a portion of said housing is formed of said damping material.
The impact rotary tool according to any one of claims 1 to 8, wherein the damping material is an alloy containing at least iron and aluminum.
The impact rotary tool according to any one of claims 1 to 8, wherein the damping material is a twin-crystal damping alloy.
The impact rotary tool according to claim 10, wherein the twin-type damping alloy is an alloy containing at least iron and copper.
The impact rotary tool according to any one of claims 1 to 8, wherein the damping material is a ferromagnetic damping alloy.
The impact rotary tool according to claim 12, wherein the ferromagnetic damping alloy is an alloy containing at least iron and chromium.