JP7258665B2 - impact tool - Google Patents

Description

The present invention relates to an impact tool configured to linearly drive a tip tool.

2. Description of the Related Art An impact tool is known that performs a machining operation on a workpiece by linearly driving a tip tool along a predetermined drive shaft. In such an impact tool, when the tip tool is not pressed against the workpiece and no load is applied (hereinafter referred to as a no-load condition), the motor is driven at a low speed so that the tip tool is pressed against the workpiece. When a load is applied (hereinafter referred to as a load state), the motor may be controlled to drive at a higher speed. For example, Patent Document 1 discloses a hammer drill that determines whether or not a load is applied to an output shaft based on acceleration detected by an acceleration detector provided in a housing, and controls driving of a motor. there is

JP-A-2018-58188

In the case of the hammer drill of Patent Document 1, in which the determination of whether or not there is a load is made based on the acceleration, even if the tip tool is not pressed against the workpiece, if the housing moves for some reason, It may be recognized as a load condition.

SUMMARY OF THE INVENTION In view of such circumstances, it is an object of the present invention to provide an impact tool capable of appropriately detecting the pressing of a tip tool against a workpiece and controlling the drive of a motor.

According to one aspect of the present invention, there is provided an impact tool configured to perform a machining operation on a workpiece by linearly driving a tip tool. This impact tool includes a motor, a drive mechanism, a tool body, an elastic connecting portion, a detection mechanism, and a control portion.

The drive mechanism is configured to linearly drive the tool bit along the drive shaft by the power of the motor. The drive shaft defines the front-rear direction of the impact tool. The tool body houses the motor and drive mechanism. The elastic coupling includes a grip that is gripped by a user. Further, the elastic connecting portion is elastically connected to the tool body so as to be relatively movable at least in the front-rear direction. It should be noted that the term "elasticly connected" here can also be translated into "connected via at least one elastic member". The detection mechanism is configured to detect pressing of the tip tool against the workpiece. The control unit is configured to control driving of the motor based on the detection result of the detection mechanism. The detection mechanism includes an interlocking member and a detector. The interlocking member is provided on one of the tool main body and the elastic connecting portion, and is configured to interlock with relative movement of the other of the tool main body and the elastic connecting portion in the front-rear direction. The detector is provided on one of the tool body and the elastic connecting portion, and is configured to detect pressing of the tip tool via movement of the interlocking member.

The impact tool of this aspect includes a detection mechanism that includes an interlocking member and a detector and is configured to detect pressing of the tip tool against the workpiece. When the tip tool is pressed against the workpiece, the elastic connecting portion elastically connected to the tool body moves forward relative to the tool body. That is, the transition from the unloaded state to the loaded state corresponds to a forward relative movement of the elastic link. In this aspect, the relative movement of the other of the tool main body and the elastic connecting portion in the front-rear direction corresponds to the movement of the interlocking member. Therefore, the detector can appropriately detect pressing of the tip tool against the workpiece (transition from unloaded state to loaded state) through the movement of the interlocking member. Then, the control unit can control the driving of the motor according to whether the tool bit is in the unloaded state or the loaded state based on the detection result by the detection mechanism.

Further, in the impact tool of this aspect, both the interlocking member and the detector of the detection mechanism are provided on one of the tool main body and the elastic connecting portion. When the interlocking member is provided on the tool main body or the elastic connecting part, and the detector is provided on the elastic connecting part or the tool main body separately from the interlocking member, due to dimensional errors of the tool main body and the elastic connecting part There is a possibility that the positional relationship between the interlocking member and the detector will differ from the original setting, and the transition from the no-load state to the loaded state cannot be accurately detected. On the other hand, according to this aspect, by arranging both the interlocking member and the detector on the same member (the tool body or the elastic connecting portion), the positional relationship between the interlocking member and the detector is stabilized, and an error is detected. The likelihood of detection can be reduced.

The tool main body in this aspect can also be called a housing. The elastic connecting portion may be configured as a handle including a grip portion and a connecting portion that connects the grip portion and the tool body, or may be configured as a housing member including a portion that covers a portion of the tool body. may have been

In this aspect, the interlocking member may be provided on one of the tool body and the elastic connecting portion so as to be interlockable with the relative movement of the other in the front-rear direction. An arrangement position or the like on one side is not particularly limited. As the interlocking member, for example, a member that contacts the other of the tool body and the elastic connecting portion (or another member integrated therewith) and rotates or moves linearly can be employed. Also, the detector may be provided on one of the tool main body and the elastic connecting portion, and should be able to detect the movement of the interlocking member. is not particularly limited. For example, as the detection method of the detector, either a non-contact method (eg, magnetic field detection method, optical method) or a contact method (eg, mechanical switch) may be adopted.

In one aspect of the invention, the detection mechanism may be configured as an assembly including the interlocking member and the detector. According to this aspect, in the process of assembling the impact tool, the worker can assemble the previously assembled single unit assembly to one of the tool main body and the elastic connecting portion. As a result, it is possible to improve the assemblability.

In one aspect of the invention, the detector may be configured to detect movement of the interlock member in a non-contact manner. According to this aspect, it is possible to protect the detector from wear and prevent deterioration in detection accuracy due to wear.

In one aspect of the present invention, the interlocking member and the detector may be provided on the tool body. According to this aspect, the interlocking member and the detector can be stably held.

In one aspect of the present invention, the tool body and the elastic connecting portion may be elastically connected so as to be slidable in the front-rear direction. According to this aspect, the relative movement of the tool body and the elastic connecting portion in the front-rear direction and the associated movement of the interlocking member are stabilized, so that the pressing of the tip tool can be detected more accurately.

In one aspect of the present invention, the gripping portion may extend in the vertical direction substantially perpendicular to the drive shaft. The tool body and the elastic connecting portion may be configured to be slidable on an upper sliding portion and a lower sliding portion that are spaced apart from each other in the vertical direction. The detection mechanism may be provided in the vicinity of the upper sliding portion or the lower sliding portion, whichever is closer to the drive shaft. In the impact tool, since the tip tool is arranged along the drive shaft, the forward relative movement of the elastic connecting part due to the pressing of the tip tool against the workpiece can be detected more accurately at a position closer to the drive shaft. Cheap. According to this aspect, the sliding in the front-rear direction of the tool body and the elastic connecting portion is stabilized by the two upper and lower sliding portions, and the tip tool can be pressed in the vicinity of the sliding portion closer to the drive shaft. It can be detected more accurately.

In one aspect of the present invention, the interlocking member has a first end and a second end, and is rotatably supported around a rotation axis located closer to the first end than the second end. It may be a lever that has been The first end is the end actuated by the other of the tool body and the resilient coupling. The second end is the end opposite the first end. The detector may then be configured to detect movement of the second end. According to this aspect, by appropriately setting the shape and size of the lever, the position of the rotation shaft, etc., it is possible to increase the degree of freedom in the arrangement position of the detector compared to the case where the interlocking member moves linearly. . Also, by setting the pivot axis closer to the first end than to the second end, the motion of the second end detected by the detector can be increased relative to the motion of the first end. can.

In one aspect of the present invention, the control unit drives the motor at a rotation speed not exceeding a predetermined rotation speed when the detector does not detect the pressing of the tip tool, and when the detector detects the pressing of the tip tool. , the motor may be configured to be driven at a rotation speed exceeding a predetermined rotation speed. According to this aspect, power saving can be achieved in a no-load state in which the tip tool is not pressed against the workpiece.

It is the side view which looked at the electric hammer whole from the left side. 1 is an overall perspective view of an electric hammer; FIG. FIG. 4 is a cross-sectional view of the electric hammer when the second housing is at the rearmost position; FIG. 4 is a partial cross-sectional view for explaining the internal structure of the electric hammer; FIG. 4 is a cross-sectional view of the electric hammer when the second housing is at the forwardmost position; It is the whole detection unit perspective view. FIG. 10 is an explanatory diagram of the detection unit when the second housing is at the rearmost position; FIG. 11 is an explanatory diagram of the detection unit when the second housing is at the forwardmost position; FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3 (however, the barrel portion is shown); FIG. 2 is a cross-sectional view taken along line XX of FIG. 1; FIG. 4 is a rear view of the crank housing and dynamic vibration absorber; 11. It is sectional drawing in the XII-XII line of FIG. It is explanatory drawing of the assembly|attachment of a dynamic vibration absorber.

An electric hammer 1 according to an embodiment of the present invention will be described below with reference to the drawings. An electric hammer (hereinafter simply referred to as a hammer) 1 is an example of an impact tool configured to linearly drive a tip tool 91 along a predetermined drive axis A1, and is used for chipping and scraping. be.

First, a schematic configuration of the hammer 1 will be described. As shown in FIGS. 1 to 3, the shell of the hammer 1 is mainly formed by a housing 20. As shown in FIGS. The housing 20 of this embodiment is configured as a so-called anti-vibration housing, and includes a first housing 21 and a second housing 25 elastically connected to the first housing 21 so as to be relatively movable.

As shown in FIG. 3, the first housing 21 is generally L-shaped when viewed from the side. The first housing 21 includes a barrel portion 22, a crank housing 23, and a motor housing 24 which are separately formed and connected to each other.

The barrel portion 22 is cylindrical and extends along a predetermined drive axis A1. A tool holder 221 to which the tip tool 91 can be attached and detached is arranged in one end portion in the axial direction of the barrel portion 22 . The crank housing 23 is a hollow body having an internal space, and is connected and fixed to the other axial end of the barrel portion 22 . The drive mechanism 4 is housed in the barrel portion 22 and the crank housing 23 . The motor housing 24 is arranged to intersect the drive shaft A<b>1 and project in a direction away from the drive shaft A<b>1 , and is connected and fixed to the crank housing 23 . A motor 31 is accommodated in the motor housing 24 . A rotation axis A2 of the motor shaft 315 is orthogonal to the drive axis A1.

In addition, in the following description, the extending direction of the driving shaft A1 of the hammer 1 is defined as the front-rear direction of the hammer 1 for convenience. In the front-rear direction, the one end side where the tool holder 221 is provided is defined as the front side (also referred to as the tip region side) of the hammer 1, and the opposite side is defined as the rear side. Also, the extending direction of the rotation axis A2 of the motor shaft 315 is defined as the vertical direction of the hammer 1 . In the vertical direction, the direction in which the motor housing 24 protrudes from the crank housing 23 is defined as downward, and the opposite direction is defined as upward. Further, a direction orthogonal to the front-rear direction and the up-down direction is defined as the left-right direction.

As shown in FIGS. 1 to 3, the second housing 25 is a generally U-shaped hollow body, and includes a grip portion 26, an upper housing 27, and a lower housing .

The grip portion 26 is configured to be grippable by the user and extends generally in the vertical direction. More specifically, the grip portion 26 is spaced rearward from the first housing 21 and extends generally in the vertical direction. A trigger 261 that can be pressed (pulled) by the user's finger is provided on the front portion of the grip portion 26 . The upper housing 27 is a portion that connects to the upper end of the grip portion 26 . In this embodiment, the upper housing 27 extends forward from the upper end of the grip portion 26 and is configured to cover the barrel portion 22 of the first housing 21 and the crank housing 23 (see FIG. 3). The lower housing 28 is a portion that connects to the lower end of the grip portion 26 . In this embodiment, the lower housing 28 extends forward from the lower end of the gripper 26 and is mostly located below the motor housing 24 . A battery mounting portion 29 is provided at substantially the central portion of the lower housing 28 in the front-rear direction. The hammer 1 operates using a battery 93 detachably attached to the battery attachment portion 29 as a power source.

With the above configuration, in the hammer 1, in addition to the second housing 25, the motor housing 24 of the first housing 21 is exposed to the outside while sandwiched between the upper housing 27 and the lower housing 28 from above and below. . A second housing 25 and a motor housing 24 form the outer surface of the hammer 1 .

A detailed configuration of the hammer 1 will be described below.

First, the anti-vibration housing structure of the housing 20 will be described. As described above, in the housing 20, the second housing 25 including the grip portion 26 is elastically connected to the first housing 21 so as to be relatively movable. As a result, transmission of vibration from the first housing 21 to the second housing 25 is suppressed.

More specifically, as shown in FIG. 3, an elastic member 501 is interposed between the crank housing 23 of the first housing 21 and the upper housing 27 of the second housing 25 . More specifically, the elastic member 501 employs a compression coil spring. A rear wall portion 231 that defines the rear end portion of the crank housing 23 is provided with a spring receiving portion. Inside the upper housing 27 (specifically, a region adjacent to the upper end of the grip portion 26), a spring receiving portion facing this spring receiving portion is provided. These spring receiving portions are configured as convex portions, respectively, and are fitted to the front end portion and the rear end portion of the elastic member 501 to support the elastic member 501 . An annular elastic member (so-called O-ring) 504 is interposed between the barrel portion 22 of the first housing 21 and the front end portion of the upper housing 27 .

Furthermore, an elastic member 505 is interposed between the motor housing 24 of the first housing 21 and the lower housing 28 of the second housing 25 . More specifically, the elastic member 505 employs a compression coil spring. A part of the lower end portion of the motor housing 24 is arranged inside the lower housing 28 and has a spring receiving portion. Inside the lower housing 28, there is provided a spring receiving portion facing this spring receiving portion. Each of these spring receiving portions is configured as a concave portion, and receives the front end portion and the rear end portion of the elastic member 505 to support the elastic member 505 .

The elastic members 501 and 505 are arranged so that the direction of their elastic force generally coincides with the front-rear direction, and the first housing 21 and the second housing 25 are arranged in the extending direction of the drive shaft A1. (the direction in which the grip portion 26 separates from the first housing 21). That is, the first housing 21 and the second housing 25 are biased forward and backward, respectively.

Furthermore, the upper housing 27 and the lower housing 28 are configured to be slidable relative to the upper end and lower end of the motor housing 24, respectively. More specifically, as shown in FIG. 4, the lower end surfaces 511 of the left and right side walls of the upper housing 27 and the upper end surfaces 513 of the left and right side walls of the motor housing 24 are in contact with each other. It is a moving surface. The lower end surface 511 and the upper end surface 513 constitute the upper sliding portion 51 . Further, guide rails 521 are provided on the left and right side walls of the lower housing 28 so as to protrude inward (the center in the left-right direction) and extend in the front-rear direction. Guide grooves 523 extending in the front-rear direction are provided at the lower ends of the left and right side walls of the motor housing 24 . The guide rail 521 is engaged with the guide groove 523 so as to be slidable in the front-rear direction. The guide rails 521 and the guide grooves 523 constitute the lower sliding portion 52 . The first housing 21 and the second housing 25 slide in the front-rear direction on the upper sliding portion 51 and the lower sliding portion 52 .

Vibration is generated in the first housing 21 by driving the tip tool 91 along the drive axis A1. Among the generated vibrations, the largest and dominant one is the vibration in the front-rear direction. On the other hand, in this embodiment, the first housing 21 and the second housing 25, which are connected via the elastic members 501, 504, 505, slide on the upper sliding portion 51 and the lower sliding portion 52. By moving relative to each other in the front-rear direction, it is possible to effectively suppress transmission of the vibration in the front-rear direction to the second housing 25 (particularly, the grip portion 26).

In addition, the first housing 21 and the second housing 25 are provided with a structure for defining a relative movable range in the front-rear direction. More specifically, as shown in FIG. 4 , a pair of inwardly projecting stopper portions 531 are provided on left and right side wall portions of the upper end portion of the lower housing 28 . Each stopper portion 531 has a recess (not shown). On the other hand, the lower end of the motor housing 24 is provided with a pair of left and right protrusions 533 projecting downward. The pair of projections 533 are arranged in the recesses of the pair of stopper portions 531, respectively. With this configuration, the first housing 21 and the second housing 25 have a position where the projection 533 abuts against the wall surface defining the front end of the recess and a position where the projection 533 abuts against the wall surface defining the rear end of the recess. Relative movement is possible in the front-rear direction between them. That is, when the projection 533 contacts the wall surface defining the front end of the recess, the second housing 25 is at the rearmost position with respect to the first housing 21, and when the projection 533 contacts the wall surface defining the rear end of the recess. , the second housing 25 can be said to be at the most forward position with respect to the first housing 21 .

As described above, the first housing 21 and the second housing 25 are biased forward and rearward by the elastic members 501 and 505, respectively. Therefore, in the initial state, the second housing 25 is held at the rearmost position with respect to the first housing 21 . Hereinafter, the rearmost position of the second housing 25 is also referred to as the initial position. As shown in FIGS. 1 and 3, when the second housing 25 is in the initial position, the position of the upper rear end of the motor housing 24 and the rear end of the crank housing 23 of the upper housing 27 in the front-rear direction. and the lower front end of the motor housing 24 and the upper front end of the lower housing 28 generally match. On the other hand, as shown in FIG. 5, when the second housing 25 is arranged at the forwardmost position with respect to the first housing 21, the motor housing 24 is arranged at a position shifted rearward from the upper housing 27 and the lower housing 28. be done.

The detailed configuration and internal structure of the first housing 21 will be described below.

First, the motor housing 24 and its internal structure will be described. As shown in FIGS. 1 to 3, the motor housing 24 is formed in the shape of a bottomed rectangular cylinder with an open top. The motor housing 24 accommodates the motor 31 , the speed change dial unit 35 and the detection unit 6 .

In this embodiment, a brushless DC motor is used as the motor 31 . Motor 31 includes a motor body 310 including a stator and a rotor, and a motor shaft 315 extending from the rotor and rotating integrally with the rotor. A vertically extending motor shaft 315 is rotatably supported by bearings at its upper and lower ends. A fan 33 is arranged between the motor body 310 and the upper bearing. The fan 33 is fixed to the motor shaft 315 and rotates together with the motor shaft 315 . The fan 33 flows into the housing 20 through an air inlet 201 (see FIG. 1), flows around the motor 31 to cool the motor 31, and then flows out of the housing 20 through an air outlet (not shown). configured to generate an airflow that The upper end of the motor shaft 315 protrudes into the crank housing 23, and a drive gear is formed in this portion. The driving gear meshes with the driven gear of the crankshaft 41 .

The speed change dial unit 35 is arranged behind the motor body 310 at the lower end of the motor housing 24 . The variable speed dial unit 35 is a device for receiving a setting input of the rotation speed of the motor 31 in response to an external operation by the user. Although not shown in detail, the speed change dial unit 35 includes a dial as an operation member that can be rotated from the outside of the motor housing 24 by the user. The variable speed dial unit 35 is connected to the controller 30 by wiring (not shown), and is configured to output to the controller 30 a signal indicating a resistance value (that is, a set rotational speed) corresponding to the rotational position of the dial. ing.

The detection unit 6 is configured to detect the relative position of the second housing 25 with respect to the first housing 21 in the front-rear direction. As shown in FIGS. 4 and 6, the detection unit 6 includes a lever 61, a hall sensor 63, and a holder 65 in this embodiment. The lever 61 and Hall sensor 63 are assembled in a holder 65 to form the detection unit 6 as a single assembly.

The holder 65 is mainly composed of a base 651 and a lever support portion 653 . The base 651 is an elongated plate-like portion fixed to the motor housing 24 . The lever support portion 653 is a plate-like portion that protrudes rearward from the back surface of the base 651 so as to be perpendicular to the base 651 .

Lever 61 includes an elongated plate-shaped lever arm 610 and a cylindrical portion 615 protruding from lever arm 610 . A magnet 62 is fixed to one surface of one end of the lever arm 610 . The lever 61 is supported by a lever support portion 653 so as to be rotatable about a rotation axis A4 extending in the left-right direction. More specifically, the lever support portion 653 is provided with a support shaft protruding rightward from the right side surface. In a state in which the cylindrical portion 615 of the lever 61 is fitted to the support shaft of the lever support portion 653, the lever 61 can be rotated to the lever support portion 653 by tightening a female screw portion formed on the support shaft. supported by Of the two ends of the lever arm 610, the end opposite to the end where the magnet 62 is fixed is the end that is actuated by the second housing 25 in accordance with the relative movement of the second housing 25. function as Hereinafter, the end opposite to the end to which the magnet 62 is fixed is referred to as a first end 611 , and the end to which the magnet 62 is fixed is referred to as a second end 612 .

Furthermore, a torsion coil spring 67 is mounted on the cylindrical portion 615 . One end of the torsion coil spring 67 is locked to the lever support portion 653 . The other end of the torsion coil spring 67 is locked near the first end 611 of the lever arm 610 . As a result, the first end 611 of the lever 61 is biased away from the base 61 , and the portion near the second end 612 is held at a position in contact with the stopper projection 655 provided on the base 651 . there is

The Hall sensor 63 is a known sensor having a Hall element and is mounted on the substrate 631 . The substrate 631 is fixed to the lever support portion 653 via screws so that the surface on which the Hall sensor 63 is mounted faces the surface of the lever arm 610 to which the magnet 62 is fixed. The Hall sensor 63 is electrically connected to the controller 30 via wiring (not shown), and outputs a specific signal (ON signal) to the controller 30 when the magnet 62 is placed within a predetermined detection range. is configured as

The detection unit 6 configured as described above is fixed to the first housing 21 by fixing the holder 65 to the motor housing 24 . More specifically, inside the motor housing 24, an inner rear wall portion 243 is provided on the rear side of the motor 31 so as to be orthogonal to the front-rear direction (see FIG. 3). The base 651 is screwed to the rear surface of the upper end of the inner rear wall 243 with the second end 612 positioned below and the first end 611 positioned above the two ends of the lever arm 610 . (not shown).

As shown in FIG. 7, the first end portion 611 of the lever arm 610 extends from the opening at the upper end of the motor housing 24 to the inside of the upper housing 27 (the space between the crank housing 23 and the rear wall portion 271 of the upper housing 27). ). A contact portion 273 projecting forward is provided at the lower end portion of the rear wall portion 271 . In this embodiment, as shown in FIGS. 3 and 7, when the second housing 25 is in the initial position (most rearmost position) with respect to the first housing 21, the lever 61 is positioned at the second end as described above. A portion near the portion 612 is held at a position abutting against the stopper projection 655, and the first end portion 611 of the lever 61 is arranged at the rearmost position within its rotatable range. At this time, the first end portion 611 is slightly separated forward from the contact portion 273 . The position of the lever 61 at this time is called the initial position of the lever 61 . When the lever 61 is in the initial position, the magnet 62 faces the Hall sensor 63 on the right side of the Hall sensor 63 and is within its detection range. Therefore, the Hall sensor 63 outputs an ON signal to the controller 30 .

On the other hand, as shown in FIGS. 5 and 8, when the second housing 25 moves forward from the initial position with respect to the first housing 21, the first end portion 611 moves through the abutting portion 273 to the torsion coil spring. Pushed forward against the biasing force of 67, the lever 61 rotates counterclockwise (in the direction of arrow CCW in FIG. 8) from the initial position in a left side view. That is, the lever 61 rotates in conjunction with the forward relative movement of the second housing 25 . When the second housing 25 relatively moves forward from the initial position to a predetermined position, the lever 61 also rotates from the initial position by a predetermined angular range and is placed at the corresponding predetermined position. Along with this, the magnet 62 leaves the detection range of the Hall sensor 63 and stops outputting the ON signal.

In this embodiment, the distance between the rotation axis A4 of the lever 61 and the second end 612 (more specifically, the distance between the magnet 62) is the distance between the rotation axis A4 and the first end 611. It is set slightly shorter than the distance (more specifically, the distance between the contact position of the first end 611 and the contact portion 273). Therefore, the movement (movement amount) of the second end portion 612 when the lever 61 rotates from the initial position to the predetermined position in conjunction with the relative forward movement of the second housing 25 is is slightly larger than the movement (movement amount) of As a result, the magnet 62 is reliably removed from the detection range of the Hall sensor 63 in conjunction with the relative forward movement of the relatively small second housing 25 .

The predetermined position of the second housing 25 (hereinafter referred to as the OFF position) is set slightly behind the forwardmost position (the position shown in FIG. 8) in the movable range of the second housing 25 . Similarly, the predetermined position of the lever 61 (hereinafter referred to as the OFF position) is set slightly behind the position (the position shown in FIG. 8) where the first end 611 is arranged at the forwardmost position in the rotatable range. ing. Hall sensor 63 does not output an ON signal when second housing 25 and lever 61 are between the OFF position and the forwardmost position.

Although the details will be described later, the detection result of the hall sensor 63 is used for drive control of the motor 31 by the controller 30 .

The crank housing 23, the barrel portion 22, and their internal structures will be described below.

As shown in FIGS. 3 and 4, the crank housing 23 is formed as a substantially rectangular hollow body. On the other hand, as shown in FIGS. 3 and 9, the barrel portion 22 is formed as an elongated cylindrical body. The crank housing 23 and the barrel portion 22 are connected and fixed to each other in the front-rear direction by a screw (not shown), and constitute a drive mechanism accommodation portion that accommodates the drive mechanism 4 . Furthermore, as shown in FIGS. 3 and 4, the lower end of the crank housing 23 is connected and fixed to the motor housing 24 by a screw 246 while being positioned within the upper end of the motor housing 24 . This forms the first housing 21 as a single housing.

The drive mechanism 4 will be explained. In this embodiment, the drive mechanism 4 is configured to perform an operation (hereinafter referred to as a hammer operation) to linearly drive the tip tool 91 along the drive axis A1 by the power of the motor 31. FIG. , includes a motion converting mechanism 40 and a striking element 46. As shown in FIG.

The motion conversion mechanism 40 is a mechanism configured to convert rotational motion of the motor shaft 315 into linear motion of the piston 43 . In this embodiment, a well-known crank mechanism including a crankshaft 41 , a connecting rod 42 , a piston 43 and a cylinder 45 is employed as the motion converting mechanism 40 .

The crankshaft 41 is arranged behind the motor shaft 315 and extends vertically. The crankshaft 41 is rotatably supported by two bearings held in the crank housing 23 about a rotation axis A3 parallel to the rotation axis A2 of the motor shaft 315 and perpendicular to the drive axis A1. The crankshaft 41 has a driven gear that meshes with the drive gear of the motor shaft 315, and rotates around the rotation axis A3 as the motor shaft 315 rotates. Further, the crankshaft 41 has an eccentric pin provided at a position eccentric from the rotation axis A3. One end of the connecting rod 42 is connected to the eccentric pin, and the other end is connected to the piston 43 via the connecting pin. The cylinder 45 is an elongated cylindrical body housed in the barrel portion 22 and extends in the front-rear direction along the drive shaft A1. The piston 43 is slidably arranged within the cylinder 45 . The piston 43 reciprocates in the front-rear direction within the cylinder 45 as the crankshaft 41 rotates.

The striking element 46 is configured to linearly move in the front-rear direction along with the reciprocating motion of the piston 43 and apply a striking force to the tip tool 91 . In this embodiment, striking element 46 includes striker 461 and impact bolt 463 . The striker 461 is arranged in the cylinder 45 so as to be slidable in the front-rear direction. An air chamber 465 is formed between the striker 461 and the piston 43 to linearly move the striker 461 through air pressure fluctuations caused by the reciprocating motion of the piston 43 . The impact bolt 463 is slidably arranged in the front-rear direction within the tool holder 221 held within the front end of the barrel portion 22 .

When the motor 31 is driven and the piston 43 is moved forward, the air in the air chamber 465 is compressed to increase the internal pressure. Therefore, the striker 461 is pushed forward at high speed by the action of the air spring, collides with the impact bolt 463 , and transmits kinetic energy to the tip tool 91 via the impact bolt 463 . The tip tool 91 receives the transmitted kinetic energy and is linearly driven along the drive axis A1 to hit the workpiece. On the other hand, when the piston 43 is moved rearward, the air in the air chamber 465 expands to reduce the internal pressure and the striker 461 is pulled rearward. The tip tool 91 moves backward by being pressed against the workpiece. In this way, the hammering action is repeated by the motion converting mechanism 40 and the striking element 46, thereby performing the chipping work and the scraping work.

By the way, as described above, when the hammer 1 performs the hammering operation, the first housing 21 undergoes relatively large vibrations in the front-rear direction. Therefore, as shown in FIGS. 4 and 10 , in this embodiment, the hammer 1 is provided with a pair of left and right dynamic vibration absorbers 7 for absorbing vibrations generated in the first housing 21 . Note that the pair of dynamic vibration absorbers 7 have the same configuration, include the drive shaft A1, and extend vertically with respect to a virtual plane P (a virtual plane including the drive shaft A1, the rotation axis A2, and the rotation axis A2). are arranged symmetrically. Further, as shown in FIG. 1, the pair of dynamic vibration reducers 7 extend in the front-rear direction slightly below the drive shaft A1 and parallel to the drive shaft A1.

A detailed configuration of the dynamic vibration reducer 7 will be described below. As shown in FIG. 10, in this embodiment, each dynamic vibration reducer 7 includes a weight 71, two springs 72 arranged on both sides of the weight 71, and a housing portion 73 housing the weight 71 and the springs 72. It is composed as the subject.

The weight 71 is formed as a long columnar member extending in the front-rear direction. More specifically, the weight 71 has a large-diameter portion 711 having a uniform diameter and a small-diameter portion 713 having a smaller diameter than the large-diameter portion 711 and protruding from the front and rear ends of the large-diameter portion 711 . The two springs 72 are each fitted in the small diameter portion 713 , and one end of each spring 72 abuts the end of the large diameter portion 711 . In the following description, when the two springs 72 are collectively referred to and when any one of them is referred to without distinction, the term "spring 72" is simply used, and when the spring 72 disposed on the front side of the weight 71 among the two springs 72 is referred to, , the front side spring 721, and when referring to the spring 72 arranged on the rear side of the weight 71, the rear side spring 723 is used.

The accommodating portion 73 is generally formed in a cylindrical shape with both ends closed, and is formed by connecting a plurality of members. In the present embodiment, the housing portion 73 is constructed using a portion of the barrel portion 22 and a portion of the crank housing 23 . More specifically, the housing portion 73 includes a first support portion 74 that is part of the barrel portion 22 , a second support portion 75 that is part of the crank housing 23 , a sleeve 76 and a cap 77 .

As shown in FIGS. 9 and 10, the pair of first support portions 74 of the pair of dynamic vibration reducers 7 are provided at the lower rear end portion of the barrel portion 22 so as to protrude leftward and rightward. The first support portion 74 is formed in a bottomed cylindrical shape with the front-rear direction as the axial direction, the front end being closed, and the rear end being open. In other words, the first support portion 74 has a recess opening rearward. The recess is configured as a stepped recess with a front portion having a smaller inner diameter than the rear portion.

As shown in FIGS. 4 and 10, the pair of second support portions 75 are provided in the lower central portion of the crank housing 23 so as to protrude left and right. The pair of second support portions 75 are arranged coaxially at positions spaced rearward from the pair of first support portions 74 . The second support portion 75 is formed in a cylindrical shape whose axial direction is the front-rear direction.

The sleeve 76 is formed as a cylindrical body separate from the first support portion 74 and the second support portion 75 . The sleeve 76 is a member for ensuring stable sliding motion of the weight 71 (specifically, the large-diameter portion 711 ), and has approximately the same inner diameter as the large-diameter portion 711 .

The cap 77 is formed in a bottomed cylindrical shape with a closed rear end and an open front end. The cap 77 is coaxially fitted and connected to the rear end of the sleeve 76 to close the opening at the rear end of the sleeve 76 . As shown in FIGS. 11 and 12, the rear end portion of the cap 77 is provided with a protrusion 771 protruding radially outward.

As shown in FIG. 10, the sleeve 76 and the cap 77 are coaxially supported by the first support portion 74 and the second support portion 75 . More specifically, the front end of the sleeve 76 is inserted into the large diameter portion of the recess of the first support portion 74 . Also, the rear end portion of the sleeve 76 and the front portion of the cap 77 are inserted into the second support portion 75 . A rear portion of the cap 77 protrudes rearward from the second support portion 75 . With such a configuration, the accommodating portion 73 having a columnar internal space (accommodating space) is formed. An O-ring 761 is attached to the front end of the sleeve 76 to seal the gap between the inner peripheral surface of the first support portion 74 and the outer peripheral surface of the sleeve 76 . At the rear end of the sleeve 76 and at the center of the cap 77 are O-rings 762 for sealing the gaps between the inner peripheral surface of the second support portion 75 and the outer peripheral surfaces of the sleeve 76 and cap 77, respectively. 773 is installed.

The weight 71 and the spring 72 are inserted into the inner space of the housing portion 73 in a state in which the two springs 72 are compressed and the large-diameter portion 711 of the weight 71 is slidable within the sleeve 76 while receiving the biasing force of the spring 72 . Contained. Also, the sleeve 76 and the cap 77 are fixedly held in the crank housing 23 by utilizing the biasing force of the spring 72 .

More specifically, a spring receiving member 725 is fitted to the front end of the front spring 721 . The spring receiving member 725 is fitted into the small diameter portion of the recess of the first support portion 74 and is in contact with the bottom surface of the recess. A rear end portion of the rear side spring 723 abuts on the cap 77 . In this embodiment, the compression of the two springs 72 urges the sleeve 76 and the cap 77 rearward, but the rearward movement is restricted by the stopper pin 772 fixed to the crank housing 23, so that the sleeve 76 and the cap 77 are held at a predetermined position. retained. Specifically, as shown in FIGS. 11 and 12, the projection 771 of the cap 77 is arranged to protrude upward, and is locked by coming into contact with the stopper pin 772 from the front, so that the sleeve 76 and the The cap 77 is positioned and held in the front-rear direction. A pair of stopper pins 772 are provided on the upper and rear sides of the pair of second support portions 75, and protrude leftward and rightward from left and right side wall portions of the crank housing 23, respectively. With this configuration, the first support portion 74 receives the forward biasing force of the spring 72 via the spring receiving member 725 , and the stopper pin 772 receives the rearward biasing force of the spring 72 via the cap 77 . there is

The central portion of the stopper pin 772 is curved and recessed, and the rear end surface of the projection 771 has a shape matching this recess. By engaging the projection 771 with the recess of the stopper pin 772 , the cap 77 is positioned and held with respect to the crank housing 23 not only in the longitudinal direction but also in the circumferential direction around the axis of the accommodating portion 73 .

In this embodiment, the dynamic vibration reducer 7 is assembled as follows.

As shown in FIG. 13, first, the operator fits the cap 77 fitted with the O-ring 773 to the sleeve 76 fitted with the O-rings 761 and 762 to connect them. Next, the operator sequentially inserts the rear spring 723 , the weight 71 , and the front spring 721 with the spring receiving member 725 fitted into the connecting body of the sleeve 76 and the cap 77 . At this time, the front end portion of the front side spring 721 including the spring receiving member 725 projects forward from the front end opening of the sleeve 76 . The operator inserts the connected body of the sleeve 76 and the cap 77 containing the weight 71 and the spring 72 into the second support portion 75 from the rear, and further inserts the front end portion of the front side spring 721 and the sleeve 76 into the first support portion. It is inserted into 74 from the rear. At this time, the operator adjusts the position of the connecting body in the circumferential direction so that the protrusion 771 does not interfere with the stopper pin 772 .

Subsequently, the operator compresses the spring 72 and pushes the cap 77 forward until the protrusion 771 is positioned forward of the stopper pin 772, and then pushes the cap 77 forward until the protrusion 771 is engaged with the concave portion of the stopper pin 772. , the cap 77 is rotated in the circumferential direction. When the operator releases the pushing of the cap 77, the projection 771 is locked to the stopper pin 772 by the biasing force of the spring 72, and the assembly is completed. A groove 775 is formed in the rear end face of the cap 77 so that the tip of a flat-blade screwdriver can be engaged therewith. Therefore, the operator can easily perform a series of operations of pushing and rotating the cap 77 using a flat-blade screwdriver.

Before the connecting body of the sleeve 76 and the cap 77 is inserted into the first support portion 74 and the second support portion 75, the space between the first support portion 74 and the second support portion 75 in the front-rear direction is: space exists. Therefore, in the present embodiment, this space is used to connect and fix the crank housing 23 to the motor housing 24 arranged below with screws 246 .

More specifically, as shown in FIGS. 4 and 13, a pair of base portions 233 are provided at the lower end of the crank housing 23. As shown in FIGS. The pair of base portions 233 are positioned between the first support portion 74 and the second support portion 75 in the front-rear direction and below the first support portion 74 and the second support portion 75 in the vertical direction. protrude to the right. On the other hand, the motor housing 24 is provided with a pair of left and right base portions 245 projecting upward. The base portion 233 and the base portion 245 are fixed by screws 246 from above the base portion 233 . In this way, using the space between the first support portion 74 and the second support portion 75, the operator can easily attach the crank housing 23 and the motor housing 24 with the screws 246 before the dynamic vibration reducer 7 is assembled. can be connected and fixed.

As shown in FIG. 13, on the rear side of the second support portion 75 (the position where the cap 77 is arranged), the crank housing 23 and the motor housing 24 are similarly separated before the dynamic vibration reducer 7 is assembled. , are connected and fixed with screws.

By the way, the dynamic vibration reducer 7 of the present embodiment is configured as a dynamic vibration reducer of a method (so-called air vibration method) that actively vibrates the weight 71 by utilizing pressure fluctuations in the barrel portion 22 and the crank housing 23. It is More specifically, as shown in FIG. 10 , the internal space of the housing portion 73 includes a front space 731 formed in front of the weight 71 by the weight 71 (more specifically, the large diameter portion 711) and It is divided into a rear side space 733 formed on the rear side.

As shown in FIG. 9, the front space 731 communicates via a passage 741 with the internal space of the barrel portion 22 that accommodates the cylinder 45 (not shown in FIG. 9). The end of the passage 741 on the front space 731 side communicates with the inside of the small diameter portion of the first support portion 74 (see FIG. 10). As mentioned above, no sleeve 76 is located in this position. Therefore, the passage 741 is formed as a single through hole extending obliquely upward from the first support portion 74 to the barrel portion 22 .

Further, as shown in FIG. 4 , the rear space 733 communicates through a passage 743 with the internal space of the crank housing 23 that accommodates the crankshaft 41 . The end of the passage 743 on the rear side space 733 side communicates with the inside of the cap 77 . Therefore, the passage 743 is formed by a through hole 744 provided in the cap 77 and a through hole 745 extending upward from the second support portion 75 to the crank housing 23 so as to be continuous with this through hole. . The through hole 744 provided in the cap 77 communicates with the through hole 745 by positioning the cap 77 in the circumferential direction by the projection 771 and the stopper pin 772 as described above.

When the hammer 1 is driven, the pressures in the inner space of the barrel portion 22 and the inner space of the crank housing 23 fluctuate with the driving of the motion conversion mechanism 40 and the striking element 46, and the pressure fluctuations are approximately 180 degrees. have a phase difference. That is, when the pressure in the internal space of the barrel portion 22 increases, the pressure in the internal space of the crank housing 23 decreases, and when the pressure in the internal space of the barrel portion 22 decreases, the pressure in the internal space of the crank housing 23 increases. There is a relationship that Therefore, by connecting the front space 731 and the rear space 733 of the dynamic vibration reducer 7 to the internal space of the barrel portion 22 and the internal space of the crank housing 23, respectively, the dynamic vibration reducer can utilize these pressure fluctuations. 7 weight 71 can be actively driven to effectively absorb vibrations. Since this air vibration method itself is known, detailed description thereof will be omitted here.

The detailed configuration and internal structure of the second housing 25 will be described below.

First, the upper housing 27 will be described. As shown in FIGS. 1 to 3, the rear portion of the upper housing 27 is formed in a substantially rectangular box shape with an open bottom and covers the crank housing 23 from above. A front portion of the upper housing 27 is cylindrical and covers the outer periphery of the barrel portion 22 . An auxiliary handle 97 (see FIGS. 1 and 2) can be attached to and detached from the outer peripheral surface of this cylindrical portion. Since the configuration of the auxiliary handle 97 is well known, detailed description thereof will be omitted here.

The grip portion 26 and its internal structure will be described. As shown in FIG. 3, the grip portion 26 is configured as a tubular portion extending in the vertical direction. A trigger 261 that can be pressed (pulled) by the operator is provided on the front portion of the grip portion 26 . A switch 263 that is switched between an on state and an off state in accordance with the operation of a trigger 261 is provided inside the grip portion 26 . The switch 263 is electrically connected to the controller 30 via wiring, and configured to output a signal indicating an ON state or an OFF state to the controller 30 .

The lower housing 28 and its internal structure will now be described. As shown in FIGS. 1 to 4, the lower housing 28 is shaped like a rectangular box with a partially open top. The lower housing 28 extends forward from the lower end of the gripper 26 and is mostly located below the motor housing 24 . Lower housing 28 includes battery mounting portion 29 , battery protection portion 280 , and connection portion 285 .

As described above, the battery mounting portion 29 is provided at the lower end portion of the lower housing 28 at the substantially central portion in the front-rear direction. In this embodiment, the battery mounting part 29 is configured such that only one rechargeable battery 93 can be attached and detached. The battery 93 detachable from the hammer 1 of this embodiment has a maximum voltage of 40 volts.

Here, the configuration of the battery 93 will be briefly described. For convenience of explanation, regarding the direction of the battery 93, the vertical direction is defined in the state that the battery 93 is attached to the hammer 1. As shown in FIG. As shown in FIGS. 3 and 4, the battery 93 has a substantially rectangular parallelepiped shape. The center of gravity G of the battery 93 is generally at the central position in any of the longitudinal (length) direction, the lateral (width) direction, and the height direction. The battery 93 has a hook 931 , a button 933 , terminals (not shown), and a pair of guide grooves 935 .

The hook 931 and terminals are provided on the top surface of the battery 93 . The hook 931 is provided at one end of the battery 93 in the longitudinal direction (perpendicular to the paper surface of FIG. 3, left and right direction of FIG. 4), and is normally biased by a spring (not shown) to protrude upward from the upper surface. there is The button 933 is provided at the upper end of the side surface of the battery 93 that defines the lateral direction. The hook 931 is configured to be retracted downward from the upper surface in response to a downward pressing operation of the button 933 . A terminal is provided on the upper surface of the battery 93 adjacent to the hook 931 . The pair of guide grooves 935 are formed as grooves extending linearly in the longitudinal direction at the upper end portions of the pair of side surfaces of the battery 93 arranged along the longitudinal direction.

As shown in FIGS. 1 to 4, in correspondence with the battery 93 having such a configuration, the battery mounting portion 29 is configured such that the upper end portion of the battery 93 is mounted with a portion of the battery 93 exposed on the lower side. configured to be In this embodiment, the battery mounting portion 29 is configured so that the battery 93 can be slidably engaged with the battery 93 in a direction in which the longitudinal direction of the battery 93 coincides with the left-right direction. Specifically, the battery mounting portion 29 has a pair of guide rails 293, a hook engaging portion 291, and a battery connection terminal (not shown). The pair of guide rails 293 extends linearly in the left-right direction and is configured to be slidably engaged with the pair of guide grooves 935 of the battery 93 . The hook engaging portion 291 is a recess recessed upward, and is configured to be able to engage with the hook 931 of the battery 93 . The battery connection terminal is configured to be electrically connected to the terminal of the battery 93 as the guide groove 935 is slidably engaged with the guide rail 293 and the hook 931 is engaged with the hook engaging portion 291 . .

In this embodiment, the battery 93 is attached to the battery attachment portion 29 by sliding the hammer 1 from left to right with the hook 931 disposed on the left side. Therefore, the hook engaging portion 291 is arranged at the left end of the battery mounting portion 29, and the battery connection terminal is configured to be connected to the terminal of the battery 93 from the right side. A button 933 for releasing the engagement of the hook 931 is provided at the upper end of the left side surface. For this reason, a concave portion 287 is provided in a portion of the lower housing 28 adjacent to the upper side of the button 933 . The concave portion 287 is configured so that the user can insert his or her finger into the concave portion 287 to facilitate the operation of the button 933 by the user.

Furthermore, when the battery 93 is attached to the battery mounting portion 29, the center of gravity G of the battery 93 is aligned in the front-rear direction (as seen from the left or right side) with the rotation axis A2 of the motor shaft 315 and the rotation axis of the crankshaft 41. It is configured to be positioned between A3 (see FIG. 3). When the battery 93 is attached to the battery mounting portion 29, the center of gravity G of the battery 93 is positioned approximately on the center line of the housing 20 (virtual plane P described above) in the left-right direction (as viewed from the front side or the rear side). (see FIG. 4).

Battery protection unit 280 and its internal configuration will be described below.

The battery protection portion 280 is configured to protect the exposed portion of the battery 93 from external forces when the battery 93 is attached to the battery attachment portion 29 . In this embodiment, the battery protection portion 280 includes a front protection portion 281 and a rear protection portion 282 provided on both sides of the battery mounting portion 29 in the front-rear direction. In this embodiment, the front protection portion 281 and the rear protection portion 282 are each formed as part of the housing 20 (lower housing 28). More specifically, the front protection portion 281 and the rear protection portion 282 are formed as hollow portions of the lower housing 28 that protrude below the battery mounting portion 29 with the battery mounting portion 29 interposed therebetween. .

As shown in FIGS. 3 and 4, with respect to the vertical direction, the lower surfaces of the front protective portion 281 and the rear protective portion 282 each protrude below the lower surface of the battery 93 mounted on the battery mounting portion 29 . is configured to In addition, the front protection portion 281 and the rear protection portion 282 are slightly shorter than the battery 93 in the left-right direction. Therefore, the left and right ends of the battery 93 slightly protrude from the lower housing 28 in the left-right direction when attached to the battery attachment portion 29 .

In this embodiment, the upper end of the battery 93 is attached to the battery attachment portion 29 and most of the battery 93 is exposed below the battery attachment portion 29 . Therefore, the front side protection portion 281 and the rear side protection portion 282 are provided so as to protect the exposed portion of the battery 93 from the battery mounting portion 29 . Specifically, the front protection portion 281 is configured to protect the front side portion of the battery 93 from external forces. On the other hand, the rear side protection portion 282 is configured to protect the rear side portion of the battery 93 from external force. More specifically, the front protection part 281 mainly protects the front side part by interfering with an external force directed toward the front side part from the front (including oblique directions) of the front protection part 281 . The rear protection part 282 mainly protects the rear side part by interfering with an external force directed toward the rear side part from behind (including oblique directions) from the rear side protection part 282 .

Also, since the battery 93 is formed in a substantially rectangular parallelepiped shape, there are four corner regions 930 at the lower end (two on the front left and right, and two on the rear left and right). These four corner areas 930 are particularly susceptible to external forces when the hammer 1 is dropped. Therefore, the front side protection portion 281 and the rear side protection portion 282 are configured to effectively protect the corner region 930 particularly from the impact when dropped. Specifically, an imaginary straight line connecting the center of gravity of the hammer 1 (including the auxiliary handle 97) when the battery 93 is attached to the battery attachment portion 29 and any corner area 930 of the lower front end of the battery 93. and further defines a virtual plane perpendicular to the virtual straight line and passing through the corner region 930, the front protection part 281 is formed to protrude in a direction away from the center of gravity from the virtual plane. It is In addition, the rear side protection portion 282 is perpendicular to an imaginary straight line connecting the center of gravity of the hammer 1 and any corner area 930 of the lower front end of the battery 93, and is perpendicular to the imaginary plane passing through the corner area 930. Protruding.

Generally, with the battery 93 installed and the center of gravity of the hammer 1 resting on the corner area 930 (in other words, in a position where the center of gravity is located directly above the corner area 930, or on the corner area 930). With the full weight of the hammer 1 acting))) If the hammer 1 falls and the corner area 930 hits the ground or floor, the impact on the corner area 930 will be greater and the potential for damage to the battery 93 will increase. . On the other hand, by forming the front side protection portion 281 and the rear side protection portion 282 so as to protrude from the imaginary plane, the hammer 1 can be moved with the center of gravity on any of the corner regions 930 of the lower end portion. Even if the mobile phone falls, the front protection part 281 or the rear protection part 282 first contacts the ground or floor, so the corner area 930 can be effectively protected.

In this embodiment, the controller 30 is housed inside the rear side protection portion 282 . Although not shown in detail, the controller 30 includes a control circuit 300 that controls driving of the motor 31, a board on which the control circuit 300 is mounted, and a case that accommodates them. The controller 30 as a whole is formed in a substantially rectangular parallelepiped shape having length, width and thickness. Of the length, width, and thickness, the length is the maximum and the thickness is the minimum. The controller 30 is arranged in the rear protection portion 282 so that the length direction, width direction, and thickness direction are aligned with the left-right direction, the up-down direction, and the front-rear direction, respectively. In this embodiment, the control circuit 300 is configured as a microcomputer including a CPU, ROM, RAM, timer, and the like. The controller 30 is electrically connected to the motor 31, the switch 263, the detection unit 6, the terminals of the battery mounting portion 29, and the like via wiring 301 (only a portion of which is shown). The drive control of the motor 31 by the controller 30 will be detailed later.

The connection portion 285 and its internal structure will be described below.

As shown in FIGS. 1 to 3, the connection portion 285 is a hollow portion that connects the lower end of the grip portion 26 and the rear protection portion 282, and connects the lower end of the grip portion 26 to the rear protection portion 282. It extends forward towards. A continuous internal space is formed inside the grip portion 26 and the lower housing 28 . The internal space of the grip portion 26 and the internal space of the rear protection portion 282 are connected via the internal space of the connecting portion 285 . Therefore, in the present embodiment, the internal space of the connection portion 285 is effectively used to electrically connect the switch 263 arranged in the grip portion 26 and the controller 30 arranged in the rear side protection portion 282. Wiring (not shown), connectors for wiring (not shown), etc. are arranged.

Furthermore, a wireless communication unit 286 is accommodated inside the connection section 285 . The wireless communication unit 286 is an electronic device capable of wireless communication with an external device. In this embodiment, the wireless communication unit 286 sends a predetermined interlocking signal using radio waves of a predetermined frequency band to a stationary dust collector (not shown) separate from the hammer 1 according to the control signal from the controller 30. configured for wireless transmission. In addition, since such a system itself is publicly known, the controller 30 causes the wireless communication unit 286 to transmit an interlocking signal while the trigger 261 is pressed and the switch 263 is turned on. . The dust collector controller is configured to drive the dust collector motor while receiving the interlock signal transmitted from the wireless communication unit 286 . That is, the user of the hammer 1 can operate the dust collector in conjunction with the hammer 1 simply by pressing the trigger 261 .

As described above, in the present embodiment, the convenience of the hammer 1 is enhanced by effectively utilizing the internal space of the connecting portion 285, which tends to be an empty space, and arranging the wireless communication unit 286 therein. In addition, the wireless communication unit 286 is not limited to transmitting an interlocking signal to the dust collector, and may be configured to perform wireless communication with other external devices (for example, a mobile terminal), or may be omitted. good too.

In addition, air inlets 201 are formed in the left and right side wall portions of the connection portion 285 to allow the inside and the outside of the connection portion 285 to communicate with each other. As the motor 31 is driven, the airflow generated by the fan 33 flows from the intake port 201 into the connecting portion 285 , passes through the lower housing 28 , and flows to the motor housing 24 . In this embodiment, the controller 30 is arranged on the path of this air flow near the intake port 201 . Therefore, the airflow generated by the fan 33 effectively cools not only the motor 31 but also the controller 30 .

Drive control of the motor 31 by the controller 30 will be described below.

In this embodiment, the controller 30 (more specifically, the control circuit 300) is configured to perform so-called soft no-load control. The soft no-load control means that, when the switch 263 is in the ON state, the rotation speed of the motor 31 is set to a predetermined relatively low rotation speed (hereinafter referred to as an initial It is a drive control method that limits the rotational speed of the motor 31 to below (referred to as the rotational speed) and allows the rotational speed of the motor 31 to exceed the initial rotational speed under load. Soft no-load control can reduce wasteful power consumption of the motor 31 in a no-load state. In this embodiment, the rotational speed set by the variable speed dial unit 35 is used as the rotational speed corresponding to the maximum amount of operation of the trigger 261 (that is, the maximum rotational speed). The rotation speed of the motor 31 is set based on the maximum rotation speed and the actual amount of operation (operating ratio) of the trigger 261 .

In this embodiment, the detection result of the detection unit 6 is used to distinguish between a no-load state and a load state in soft no-load control. As described above, the Hall sensor 63 of the detection unit 6 detects, via the magnet 62, the position of the lever 61 interlocked with the relative movement of the second housing 25 with respect to the first housing 21, thereby It detects the relative position of the second housing 25 .

In the no-load state, the biasing force of the elastic members 501 and 505 places the second housing 25 at the rearmost position (initial position), and the lever 61 is also placed at the initial position (see FIGS. 3 and 7). . Therefore, the hall sensor 63 detects the magnet 62 and the detection unit 6 outputs an ON signal. The controller 30 determines that the motor 31 is in the no-load state when the output from the detection unit 6 is on. The controller 30 starts driving the motor 31 when the switch 263 is turned on from the off state. At this time, if the rotation speed calculated based on the maximum rotation speed and the operation amount of the trigger 261 is equal to or lower than the initial rotation speed, the calculated rotation speed is set as the rotation speed of the motor 31 as it is. On the other hand, when the calculated rotation speed exceeds the initial rotation speed, the initial rotation speed is set as the rotation speed of the motor 31 . As the motor 31 is driven, the drive mechanism 4 is driven to perform a hammering action.

When the user presses the tip tool 91 against the workpiece while gripping the grip portion 26 , the second housing 25 is moved against the second housing 25 at the upper sliding portion 51 and the lower sliding portion 52 . It slides and moves forward from the initial position while compressing the elastic members 501 and 505 . In conjunction with the forward relative movement of the second housing 25, the lever 61 also rotates from the initial position. When the second housing 25 and the lever 61 reach the off position, the hall sensor 63 stops outputting the on signal. The controller 30 recognizes the change from on to off of the output from the hall sensor 63 as the transition from the no-load state to the load state.

When the controller 30 recognizes the shift to the load state, it drives the motor 31 at a rotational speed calculated based on the maximum rotational speed and the amount of operation of the trigger 261 . At this time, when the rotation speed of the motor 31 is increased to the calculated rotation speed, the controller 30 may immediately increase the rotation speed to that speed or gradually increase the rotation speed. The controller 30 stops driving the motor 31 when the trigger 261 is released and the switch 263 is turned off. Note that when the switch 263 is turned on while the output from the hall sensor 63 is off (that is, in a load state), the controller 30 calculates the maximum rotation speed and the operation amount of the trigger 261. The motor 31 is started to be driven at a rotational speed of .

The controller 30 stops driving the motor 31 when the trigger 261 is released and the switch 263 is turned off.

When the switch 263 is in the ON state, the controller 30 changes the output from the Hall sensor 63 from OFF to ON (that is, the relative movement of the second housing 25 and the lever 61 from the OFF position to the initial position, from the load state). The motor 31 may be configured to limit the rotation speed of the motor 31 to the initial rotation speed or less when the transition to the no-load state is recognized. In this case, for example, the controller 30 monitors the duration of the ON state of the Hall sensor 63 after the change by using a timer. Then, only when the ON state continues for a predetermined period of time, the rotation speed of the motor 31 may be limited to the initial rotation speed or less. This is to reliably distinguish between a temporary change to the ON state when the first housing 21 is vibrating during machining and a change from the loaded state to the unloaded state.

Specifically, the second housing 25 reciprocates in the front-rear direction with respect to the first housing 21 due to the vibration of the first housing 21 in the front-rear direction. In conjunction with this, the lever 61 having the magnet 62 also rotates. In this case, the output from Hall sensor 63 may switch between on and off in short cycles. On the other hand, when the pressing of the tip tool 91 is released and the state shifts to the no-load state, the ON state continues for a predetermined time after the output from the Hall sensor 63 is switched from OFF to ON. Therefore, if the control as described above is adopted, the controller 30 can more reliably recognize the transition from the load state to the no-load state based on the detection result of the Hall sensor 63 .

As described above, the hammer 1 of the present embodiment includes the first housing 21 that houses the motor 31 and the drive mechanism 4, and the grip portion 26, and is movable relative to the first housing 21 at least in the front-rear direction. and a second housing 25 elastically connected to the housing. Further, the hammer 1 is configured to control the driving of the motor 31 based on the detection unit 6 configured to detect the pressing of the tip tool 91 against the workpiece, and the detection result of the detection unit 6. A controller 30 (more specifically, a control circuit 300) is provided. The detection unit 6 includes a lever 61 provided in the first housing 21 and configured to interlock with the relative movement of the second housing 25 in the front-rear direction, and a lever 61 provided in the first housing 21 to detect the movement of the lever 61. and a Hall sensor 63 configured to detect the pressing of the tip tool 91 via.

When the tip tool 91 is pressed against the workpiece, the second housing 25 elastically connected to the first housing 21 moves forward relative to the first housing 21 . That is, the transition from the unloaded state to the loaded state corresponds to the forward relative movement of the second housing 25 . The relative movement of the second housing 25 in the front-rear direction corresponds to the movement of the lever 61 . Therefore, the Hall sensor 63 detects the pressing of the tip tool 91 against the workpiece via the movement of the lever 61 (specifically, whether or not the magnet 62 attached to the second end 612 of the lever 61 is detected). transition from load state to load state) can be detected appropriately. Then, the controller 30 can control the drive of the motor 31 based on the result of detection by the detection unit 6, depending on whether the tip tool 91 is in the unloaded state or in the loaded state.

In this embodiment, both the lever 61 and Hall sensor 63 of the detection unit 6 are provided on the same first housing 21 . If the lever 61 is provided in one of the first housing 21 and the second housing 25 and the Hall sensor 63 is provided in the other, the lever 61 may and the Hall sensor 63 will be different from the original setting, and the Hall sensor 63 may not be able to accurately detect the transition from the no-load state to the loaded state. On the other hand, by arranging both the lever 61 and the Hall sensor 63 in the same first housing 21 as in the present embodiment, the positional relationship between the lever 61 and the Hall sensor 63 is further stabilized, and erroneous detection is prevented. Possibility can be reduced.

In this embodiment, the detection unit 6 is constructed as one assembly including the lever 61 and the Hall sensor 63 . Therefore, in the process of assembling the hammer 1, the operator can assemble the detection unit 6, which is a previously assembled single assembly, to the first housing 21, thereby improving assembling efficiency.

Further, the Hall sensor 63 can detect the movement of the lever 61 without contact by detecting the magnet 62 attached to the lever 61 . Therefore, the Hall sensor 63 does not wear out due to contact with the object to be detected, and deterioration of detection accuracy due to wear can be prevented.

In addition, in the present embodiment, the interlocking member that interlocks with the relative movement of the second housing 25 in the front-rear direction has the first end portion 611 and the second end portion 612 , and the first end portion A lever 61 that is rotatably supported around a rotation axis A4 located near the portion 611 is employed. In this case, by appropriately setting the shape and size of the rotary lever 61, the position of the rotary shaft A4, etc., the arrangement position of the hall sensor 63 can be adjusted as compared with the case where an interlocking member that moves linearly is adopted. It can increase the degree of freedom. Also, by setting the pivot axis A4 closer to the first end 611 actuated by the second housing 25 than to the second end 612 used to detect the movement of the lever 61, the second end Movement of 612 can be increased relative to movement of first end 611 . Therefore, relatively small relative movement of the second housing 25 makes it possible to reliably move the magnet 62 out of the detection range of the hall sensor 63 .

Furthermore, in this embodiment, the first housing 21 and the second housing 25 are elastically connected so as to be slidable in the front-rear direction. As a result, the relative movement of the first housing 21 and the second housing 25 in the front-rear direction and the accompanying movement of the lever 61 are stabilized, and the pressing of the tip tool 91 can be detected more accurately. In particular, in this embodiment, the first housing 21 and the second housing 25 are provided with two sliding portions (an upper sliding portion 51 and a lower sliding portion 52) that are spaced apart from each other in the vertical direction. there is That is, the first housing 21 and the second housing 25 are slidable at two upper and lower positions. The detection unit 6 is provided in the vicinity of the upper sliding portion 51 closer to the drive shaft A1 than the upper sliding portion 51 and the lower sliding portion 52 . In the hammer 1, since the tip tool 91 is arranged along the drive axis A1, the forward relative movement of the second housing 25 accompanying the pressing of the tip tool 91 against the workpiece is directed toward the position closer to the drive axis A1. is easy to detect accurately. In this embodiment, the sliding of the first housing 21 and the second housing 25 in the front-rear direction is further stabilized by the two sliding portions, and in the vicinity of the upper sliding portion 5 closer to the drive shaft A1, the tip tool The pressing of 91 can be detected more accurately.

Further, in the present embodiment, the controller 30 (control circuit 300) sets a predetermined rotation speed (initial rotation speed ) to drive the motor 31 at a rotational speed not exceeding Further, the controller 30 (control circuit 300) starts the motor at a rotation speed exceeding the initial rotation speed when the Hall sensor 63 detects the pressing of the tip tool 91 (when the output of the Hall sensor 63 changes from ON to OFF). 31 can be driven. As a result, it is possible to save power in a no-load state in which the tip tool 91 is not pressed against the workpiece.

The hammer 1 of this embodiment also includes a first housing 21 that houses the motor 31 and the drive mechanism 4 and two dynamic vibration absorbers 7 . Drive mechanism 4 is configured as a crank mechanism including crankshaft 41 , piston 43 and cylinder 45 . The first housing 21 includes a motor housing 24 that accommodates the motor 31, a crank housing 23 that accommodates the crankshaft 41, and a cylindrical barrel portion 22 that is arranged on the front side of the crank housing 23 and accommodates the cylinder 45. . Each dynamic vibration reducer 7 includes a weight 71 , two springs 72 arranged on the front side and rear side of the weight 71 , and a housing portion 73 housing the weight 71 and the spring 72 . A first support portion 74 and a second support portion 75, which are part of the housing portion 73, are formed by a portion of the barrel portion 22 and a portion of the crank housing 23, respectively.

Therefore, for example, even if the length of the crank housing 23 in the front-rear direction is less than the length required for the dynamic vibration reducer 7, the dynamic vibration reducer 7 is arranged using the barrel portion 22 and part of the crank housing 23. can do. That is, the dynamic vibration reducer 7 can be arranged rationally without being restricted by the longitudinal length of the crank housing 23 .

Furthermore, in the present embodiment, the accommodating portion 73 of the dynamic vibration reducer 7 includes a cylindrical sleeve 76 that accommodates at least a portion of the weight 71 and extends in the front-rear direction. The first support portion 74 and the second support portion 75 are arranged apart from each other in the front-rear direction and support the sleeve 76 . With such a configuration, for example, by appropriately changing the distance between the first support portion 74 and the second support portion 75 and the length of the sleeve 76, the length of the housing portion 73 in the front-rear direction (the stroke of the weight 71 length) can be set. Therefore, the degree of freedom in setting the length of the accommodation portion 73 can be increased.

Further, in this embodiment, the sleeve 76 is held by the first housing 21 (specifically, the crank housing 23) using the biasing force of the spring 72. As shown in FIG. Therefore, since it is not necessary to fix the sleeve 76 to the first housing 21 with a screw or the like, the operator can easily assemble and disassemble the accommodating portion 73 .

Furthermore, in the present embodiment, the first support portion 74 is configured as a spring receiving portion that receives the forward biasing force of the spring 72 . More specifically, the first support portion 74 is formed in a bottomed tubular shape with a closed front end, and receives the front end portion while holding the spring 72 (front side spring 721) inserted therein. With such a configuration, the springs 72 can be efficiently arranged without increasing the number of parts.

Moreover, in this embodiment, the two dynamic vibration reducers 7 are arranged symmetrically with respect to the virtual plane P including the drive axis A1. Therefore, the two dynamic vibration absorbers 7 can absorb vibrations on both sides of the virtual plane P in a well-balanced manner.

Further, in the present embodiment, the internal space of the housing portion 73 includes a front space 731 formed on the front side of the weight 71 and a rear space 733 formed on the rear side of the weight. The first support portion 74 has a passage 741 that communicates the interior space of the barrel portion 22 with the front space 731, and the second support portion 75 communicates the interior space of the crank housing 23 with the rear space 733. It has a passage 743 that allows According to such a configuration, pressure fluctuations in the internal space of the barrel portion 22 and the internal space of the crank housing 23 can be used to positively vibrate the weight. Thereby, vibration can be absorbed more effectively.

Further, the hammer 1 of the present embodiment includes a housing 20 that accommodates the motor 31 and the drive mechanism 4, and a battery mounting portion 29 that is provided in the housing 20 and to which one substantially rectangular parallelepiped battery 93 can be attached and detached. there is The drive mechanism 4 is configured as a crank mechanism including a crankshaft 41 . The crankshaft 41 is arranged on the rear side of the motor shaft 315 and is rotatable around a rotation axis A3 parallel to the rotation axis A2 of the motor shaft 315 . The battery mounting portion 29 is arranged below the motor 31 . In addition, the battery mounting portion 29 can mount the battery 93 in the left-right direction, and when the battery 93 is mounted, the center of gravity G of the battery 93 is aligned with the rotation axis in the front-rear direction (that is, when viewed from the right or left side). It is configured to be positioned between A2 and the rotation axis A3.

With such a battery mounting portion 29, the housing 20 can be made more compact in the front-rear direction than when a plurality of batteries are mounted side by side in the front-rear direction. In addition, in the present embodiment, the battery mounting portion 29 is further configured so that the battery 93 can be mounted in such a direction that the longitudinal direction of the battery 93 coincides with the left-right direction. Therefore, the housing 20 can be made more compact in the front-rear direction than when one battery is mounted with its longitudinal direction aligned with the front-rear direction. Further, the battery mounting portion 29 is configured such that the center of gravity of the battery 93 when mounted in the battery mounting portion 29 is located near the center of gravity of the motor 31 and the crankshaft 41, which are relatively heavy. . Such centralization of the center of gravity makes it possible to prevent the center of gravity of the battery 93 from moving away from the center of gravity of the hammer 1, thereby realizing the hammer 1 with excellent workability.

In addition, in the present embodiment, the hammer 1 has a front protection portion 281 and a rear protection portion 282 provided on the front side and rear side of the battery mounting portion 29 in the front-rear direction. The front protection portion 281 and the rear protection portion 282 are configured to protect the front side portion and the rear side portion of the battery 93 from external forces, respectively. The exposed portion of the battery 93 attached to the battery attachment portion 29 is a portion that is easily damaged when an external force is applied. On the other hand, by providing the front side protection portion 281 and the rear side protection portion 282, the possibility of the battery 93 being damaged can be reduced. Further, in this embodiment, the front protector 281 and the rear protector 282 are configured to protect the lower front edge and lower rear edge corner regions 930 from external forces, respectively. Therefore, the possibility of damage to the corner region 930 due to impact, especially when dropped, can also be effectively reduced. Since the front protection part 281 and the rear protection part 282 are formed by a part of the housing 20, the function of protecting the battery 93 can be added to the hammer 1 without increasing the number of parts.

Further, in the present embodiment, a controller 30 including a control circuit 300 configured to control driving of the motor 31 is arranged inside the rear protection section 282 . Further, controller 30 has a substantially rectangular parallelepiped shape having a length, width and thickness. Of the length, width and thickness, the length is the maximum and the thickness is the minimum. The controller 30 is arranged in such a direction that the thickness direction coincides with the front-rear direction and the length direction coincides with the left-right direction. In this manner, the internal space of the rear protection portion 282, which tends to be empty space, is effectively used to suppress the lengthening of the rear protection portion 282 in the front-rear direction and the vertical direction, while the controller 30 controls the rear protection portion. 282 are rationally located.

Furthermore, the hammer 1 is configured to be grippable by the user, and has a tubular grip portion 26 extending in the vertical direction, which connects the lower end of the grip portion 26 and the rear end portion of the rear side protection portion 282 . and a hollow connecting portion 285 . Therefore, the internal space of the connecting portion, which tends to become an empty space, can be effectively used as an arrangement space for various parts, wiring, connectors, and the like.

Correspondence between each component of the above embodiment and each component of the present invention is shown below. The electric hammer 1 is an example of a "percussion tool." The tip tool 91 is an example of a "tip tool." The motor 31 is an example of a "motor". The drive mechanism 4 is an example of a "drive mechanism." The drive shaft A1 is an example of a "drive shaft". The first housing 21 is an example of a "tool main body". The second housing 25 and the gripping portion 26 are examples of the "elastic connecting portion" and the "gripping portion", respectively. The detection unit 6 is an example of a "detection mechanism". The controller 30 (specifically, the control circuit 300) is an example of a "control section." The lever 61 (specifically, the lever arm 610) and the Hall sensor 63 are examples of the "interlocking member" and the "detector", respectively. The upper sliding portion 51 and the lower sliding portion 52 are examples of the “upper sliding portion” and the “lower sliding portion”, respectively. The first end 611, the second end 612, and the rotation axis A4 of the lever arm 610 are examples of the "first end," the "second end," and the "rotation axis," respectively. The initial rotation speed is an example of a "predetermined rotation speed".

Note that the above-described embodiment is merely an example, and the impact tool according to the present invention is not limited to the configuration of the hammer 1 illustrated. For example, the modifications exemplified below can be made. It should be noted that one or more of these modifications can be employed in combination with the hammer 1 shown in the embodiment or the inventions described in each claim.

In the above-described embodiment, as an example of the impact tool, the hammer 1 configured to perform only the hammering action of linearly driving the tip tool 91 is exemplified. However, the invention may be embodied in other impact tools capable of performing actions other than hammering action. For example, the impact tool may be a hammer drill capable of executing not only the hammering action but also the drilling action of rotationally driving the tip tool 91 around the drive axis A1.

In addition, depending on the impact tool, the configuration of the motor 31, the drive mechanism 4, the first housing 21 (tool main body) that houses the motor 31 and the drive mechanism 4, and the second housing 25 (elastic connection portion) having the grip portion 26, The arrangement relationship can be changed as appropriate. Examples of changes that can be adopted for these are given below.

The motor 31 may be a motor having brushes instead of a brushless motor. Alternatively, the motor 31 may be an AC motor. In this case, the housing 20 is provided with a power cable connectable to an external commercial power source instead of the battery mounting portion 29, and the battery protection portion 280 is omitted. Further, as the motion conversion mechanism 40 of the drive mechanism 4, a well-known motion conversion mechanism using a swing member may be employed instead of the crank mechanism of the above embodiment.

The shapes of the first housing 21 and the second housing 25 can be changed as appropriate. For example, in the above-described embodiment, the second housing 25 elastically connected to the first housing 21 has a structure that partially covers the first housing 21. The scope is not limited to the exemplary embodiments. Arrangement positions, types, and numbers of the elastic members 501 and 505 interposed between the first housing 21 and the second housing 25 can also be arbitrarily selected. As the elastic members 501 and 505, in addition to compression coil springs, various types of springs, rubber, and elastic synthetic resin can be used.

Also, a handle including a grip portion may be elastically connected to the body housing that accommodates the motor 31 and the drive mechanism 4 . In this case, each of the upper and lower ends of the handle may be connected to the body housing via one or more elastic members, or only the upper end of the handle may be elastically connected to the body housing in a cantilevered manner. good too. Further, the upper end of the handle is elastically connected to the main body housing so as to be relatively movable in the front-rear direction, while the lower end of the handle is supported by the main housing so as to be rotatable about a pivot shaft extending in the left-right direction. may be The elastic members interposed between the body housing and the handle are similar to the elastic members 501 and 505 .

The portions (sliding portions) in which the first housing 21 and the second housing 25 slide in the front-rear direction are not limited to the upper sliding portion 51 and the lower sliding portion 52 . For example, the sliding portion may be provided only at one position in the vertical direction. Also, a plurality of sliding portions may be provided at positions different from those exemplified in the above embodiments. Alternatively, the sliding portion may be omitted.

The battery mounting part 29 may be modified so that a plurality of batteries 93 can be attached and detached. In this case, the position of the battery mounting portion 29 and the configuration of the battery protection portion 280 are appropriately changed. Also, the battery protection unit 280 may be omitted.

Furthermore, the configuration and arrangement position of the detection unit 6 for detecting the pressing of the tip tool 91 against the workpiece are not limited to the examples in the above embodiment. Specifically, the detection unit 6 is provided in one of the first housing 21 and the second housing 25, and an interlocking member that interlocks with the relative movement in the front-rear direction of the other, and the same one as the interlocking member, which interlocks. It can be modified as appropriate as long as it includes a detector that detects pressing of the tip tool 91 against the workpiece through movement of the member.

For example, instead of the rotating lever 61, a linearly movable interlocking member may be employed. In this case, for example, the interlocking member is provided in one of the first housing 21 and the second housing 25, and contacts the other (or another member integrated therewith) to move in the front-rear direction. be done. Further, the interlocking member may be composed of a plurality of members (for example, a rotatable member and a linearly movable member) that are combined with each other. Further, the interlocking member may be attached to the rear wall portion 231 of the crank housing 23 in the first housing 21 and operated by the upper housing 27, or may be attached to the lower end portion of the motor housing 24 and operated by the lower housing 24, for example. It may be actuated by side housing 28 . Alternatively, the interlocking member may be attached to the second housing 25 instead of the first housing 21 and configured to interlock with the relative movement of the first housing 21 with respect to the second housing 25 in the front-rear direction.

Further, the detection method of the detector is not particularly limited, and instead of the magnetic field detection type Hall sensor 63, an optical sensor may be adopted, or a contact type mechanical switch may be adopted. good. The detector needs to be attached to the same one of the first housing 21 and the second housing 25 as the interlocking member, but the position can be appropriately set according to the configuration of the interlocking member and the detection method.

In the embodiment described above, the detection unit 6 is configured as an assembly including the lever 61 and the Hall sensor 63 . However, the lever 61 and Hall sensor 63 may each be supported by separate holders and attached to the first housing 21 or the second housing 25 .

In the above embodiment, the hammer 1 has a pair of left and right dynamic vibration absorbers 7 . However, the configuration, arrangement position, and number of the dynamic vibration reducers 7 can be changed as appropriate. Note that the dynamic vibration reducer 7 may be omitted.

In the above embodiment, the controller 30 (control circuit 300) is configured to perform soft no-load control based on the detection result of the detection unit 6. FIG. Alternatively, the controller 30 (control circuit 300) does not drive the motor 31 while the Hall sensor 63 does not detect the pressing of the tip tool 91, and in response to the detection of the pressing of the tip tool 91 by the Hall sensor 63, It may be configured to start driving the motor 31 . In this case, further power saving can be achieved in the no-load state. It should be noted that the drive control processing of the motor 31 is not performed by the control circuit 300 configured by a microcomputer, but by another type of control circuit, such as an ASIC (Application Specific Integrated Circuits) or an FPGA (Field Programmable Gate Array). It may be performed by a logic device. Further, the drive control process of the motor 31 may be distributed by a plurality of control circuits.

Furthermore, in view of the gist of the present invention and the above-described embodiments, the following aspects are constructed. The following aspects can be employed in combination with the hammer 1 shown in the embodiment, the above modifications, or the inventions described in each claim.
[Aspect 1]
The detection mechanism further includes a biasing member that biases the lever in a direction in which the first end contacts the other of the tool body and the elastic connecting portion.
The torsion coil spring 67 is an example of the "biasing member" in this aspect. Instead of the torsion coil spring 67, other types of springs, rubber, or elastic synthetic resin may be employed.
[Aspect 2]
The elastic connecting portion is configured to move forward with respect to the tool body from a first position to a second position in response to pressing of the tip tool against the workpiece,
The interlocking member is configured to move from a third position to a fourth position in conjunction with relative movement of the elastic connecting portion from the first position to the second position,
The detector is configured to detect movement of the interlock member from the third position to the fourth position.

1: electric hammer, 20: housing, 201: intake port, 21: first housing, 22: barrel portion, 221: tool holder, 23: crank housing, 231: rear wall portion, 233: base portion, 24: motor housing , 243: inner rear wall portion, 245: base portion, 246: screw, 25: second housing, 26: grip portion, 261: trigger, 263: switch, 27: upper housing, 271: rear wall portion, 273: contact contact portion 28: lower housing 280: battery protection portion 281: front side protection portion 282: rear side protection portion 285: connection portion 286: wireless communication unit 287: concave portion 29: battery mounting portion 291 : hook engaging portion 293: guide rail 30: controller 300: control circuit 301: wiring 31: motor 310: motor main body 315: motor shaft 33: fan 35: speed change dial unit 4 : drive mechanism, 40: motion conversion mechanism, 41: crankshaft, 42: connecting rod, 43: piston, 45: cylinder, 46: striking element, 461: striker, 463: impact bolt, 465: air chamber, 5: upper side Sliding portion, 501: elastic member, 504: elastic member, 505: elastic member, 51: upper sliding portion, 511: lower end surface, 513: upper end surface, 52: lower sliding portion, 521: guide rail, 523 : guide groove, 531: stopper portion, 533: projection, 6: detection unit, 61: lever, 610: lever arm, 611: first end portion, 612: second end portion, 615: cylindrical portion, 62: magnet, 63: Hall sensor, 631: Substrate, 65: Holder, 651: Base, 653: Lever support portion, 655: Stopper projection, 67: Coil spring, 7: Dynamic vibration absorber, 71: Weight, 711: Large diameter portion, 713: Small diameter portion 72: Spring 721: Front side spring 723: Rear side spring 725: Spring receiving member 73: Accommodating portion 731: Front side space 733: Rear side space 74: First support portion 741: Passage , 743: Passage, 744: Through hole, 745: Through hole, 75: Second support portion, 76: Sleeve, 761: O-ring, 762: O-ring, 77: Cap, 771: Protrusion, 772: Stopper pin, 773 : O-ring, 775: groove, 81: tip tool, 91: tip tool, 93: battery, 930: corner area, 931: hook, 933: button, 935: guide groove, 97: auxiliary handle, A1: drive shaft , A2: rotation axis, A3: rotation axis, A4: rotation axis

Claims (7)

An impact tool configured to perform a machining operation on a workpiece by linearly driving the tip tool,
a motor;
a drive mechanism configured to linearly drive the tip tool along a drive shaft defining the longitudinal direction of the impact tool by the power of the motor;
a tool body housing the motor and the drive mechanism;
an elastic connecting portion including a grasping portion grasped by a user and elastically connected to the tool body so as to be relatively movable at least in the front-rear direction;
a detection mechanism configured to detect pressing of the tip tool against the workpiece;
a control unit configured to control driving of the motor based on a detection result by the detection mechanism;
The detection mechanism is
an interlocking member provided on one of the tool main body and the elastic connecting portion and configured to interlock with the relative movement of the other of the tool main body and the elastic connecting portion in the front-rear direction;
a detector provided on the one of the tool body and the elastic connecting portion and configured to detect the rearward pressing of the tip tool through the movement of the interlocking member ;
The interlocking member has a first end operated by the other of the tool body and the elastic connecting portion, and a second end opposite to the first end. A lever rotatably supported around a rotation axis located closer to the first end than
An impact tool , wherein the detector is configured to detect movement of the second end . The impact tool according to claim 1,
An impact tool, wherein the detection mechanism is configured as one assembly including the interlocking member and the detector. The impact tool according to claim 1 or 2,
The impact tool, wherein the detector is configured to detect the movement of the interlocking member in a non-contact manner. The impact tool according to any one of claims 1 to 3,
A striking tool, wherein the detection mechanism is provided in the tool body. The impact tool according to any one of claims 1 to 4,
The impact tool, wherein the tool body and the elastic connecting portion are elastically connected so as to be slidable in the longitudinal direction. An impact tool according to claim 5,
The gripping portion extends in a vertical direction generally perpendicular to the drive shaft,
The tool body and the elastic connecting portion are configured to be slidable on the upper sliding portion and the lower sliding portion that are spaced apart from each other in the vertical direction,
The impact tool, wherein the detection mechanism is provided in the vicinity of the upper sliding portion or the lower sliding portion, whichever is closer to the drive shaft. The impact tool according to any one of claims 1 to 6 ,
The control unit
when the detector does not detect the pressing of the tip tool, driving the motor at a rotational speed that does not exceed a predetermined rotational speed;
An impact tool, wherein the motor can be driven at a rotational speed exceeding the predetermined rotational speed when the detector detects that the tip tool is pressed.

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