impact tools

Abstract

The present application provides a kind of impact tool.The hammer drill (1) has motor (2), drive mechanism, main body shell (11), handle shell (15), front side guide (61) and rear side guide (62).Drive mechanism can at least execute the impact action of linearly driving top end tool along the drive axis (A1) parallel with the rotation axis (A2) of motor shaft (25).Handle shell (15) includes grip (17), and is formed into annular shape.Handle shell (15) is connected with main body shell (11) via elastic component (51).Front side guide (61) and rear side guide (62) guide the relative sliding of main body shell (11) and handle shell (15) in front and back direction.Rear side guide (62) is away from front side guide (61), and is configured at the position more rear than front side guide (61).Accordingly, the sliding of main body shell and handle shell can be guided in front and back direction with high precision and stability.

Description

Technical Field

[0001] The present invention relates to an impact tool configured to drive a tip tool in a linear manner. Background Art

[0002] In an impact tool that processes a workpiece by driving a top tool in a straight line along a drive axis, particularly large vibrations are generated in the direction in which the drive axis extends. In response to this, various vibration-isolating housing structures have been proposed. For example, in a hammer drill disclosed in Japanese Invention Patent Publication No. 2016-93867, a handle portion including a grip portion is elastically connected to a main body portion that houses a motor and a drive mechanism in a manner that allows movement in the direction in which the drive axis extends (front-back direction). In addition, a sliding guide portion is provided for guiding the movement of the handle portion relative to the main body portion. Summary of the Invention

[0003] [Technical problem to be solved by the invention]

[0004] The sliding guide portion includes a plurality of guide grooves and a plurality of small-diameter guide pins that abut and slide within the guide grooves. The guide grooves are circumferentially spaced apart on the inner surface of the cylindrical portion of the handle and extend in the front-to-back direction. The guide pins are circumferentially spaced apart on the outer surface of the cylindrical motor housing and extend in the front-to-back direction. In this structure, dimensional errors between the guide pins and the guide grooves may cause play.

[0005] An object of the present invention is to provide an impact tool with an improved guide structure, the impact tool comprising a main body and a handle portion elastically connected in a relatively movable manner.

[0006] [Methods used to solve technical problems]

[0007] According to one aspect of the present invention, there is provided an impact tool including a motor, a drive mechanism, a main body housing, a handle housing, a first guide portion, and a second guide portion.

[0008] The motor has a stator, a rotor and a motor shaft. The motor shaft extends from the rotor and is rotatable around a first axis integrally with the rotor. The drive mechanism is configured to perform at least an impact action by the power of the motor. The impact action refers to the action of driving the top tool in a straight line along the second axis. The second axis extends parallel to the first axis. In addition, the second axis defines the front and rear direction of the impact tool. The main body shell accommodates the motor and the drive mechanism. The handle shell includes an elongated grip portion. The grip portion extends behind the main body shell in a direction intersecting the second axis. The handle shell is formed in a ring shape. The handle shell is connected to the main body shell by a first elastic component in a manner that can move at least in the front and rear direction relative to the main body shell.

[0009] The first guide portion and the second guide portion are configured to guide the relative sliding of the main body shell and the handle shell in the front-to-back direction. The first guide portion and the second guide portion respectively include a first engaging portion and a second engaging portion, wherein the first engaging portion is provided on the main body shell; the second engaging portion is provided on the handle shell and engages with the first engaging portion in a manner that allows sliding along the front-to-back direction. The second guide portion is separated from the first guide portion and is arranged at a position farther back than the first guide portion. In addition, the first engaging portion and the second engaging portion of the first guide portion and the first engaging portion and the second engaging portion of the second guide portion may have the same structure or different structures.

[0010] The impact tool of this embodiment includes a first guide portion and a second guide portion, which are arranged separately in the front-to-back direction and are configured to guide the relative sliding of the main body housing and the handle housing in the front-to-back direction. This guide structure can guide the sliding of the main body housing and the handle housing in the front-to-back direction with high precision and stability, compared to a case where multiple guide portions are provided along the circumference of the main body housing and the handle housing at approximately the same position in the front-to-back direction.

[0011] In one embodiment of the present invention, at least one of the first guide portion and the second guide portion may be arranged at a position further back than the rear end of the motor stator. In this case, by guiding the sliding movement of the main body housing and the handle housing at a position closer to the grip portion, operability can be improved.

[0012] In one embodiment of the present invention, the first guide portion may be arranged radially outward of the stator. In this case, by arranging the first guide portion on the front side near the motor as a weight, the sliding of the main body housing and the handle housing can be guided more stably.

[0013] In one embodiment of the present invention, the main body housing may also include a stator housing portion and a first extension portion, wherein the stator housing portion houses the stator. When a direction orthogonal to the second axis and corresponding to the extension direction of the handle portion is defined as the up-down direction, the first extension portion extends rearward relative to the stator housing portion at a position above the first axis. The handle housing may include a cover portion and a second extension portion. The cover portion at least partially surrounds the stator housing portion in a circumferential direction around the first axis. The second extension portion extends forward from the upper end of the handle portion and is connected to the cover portion, covering at least a portion of the first extension portion. Furthermore, the first engaging portion of the second guide portion may be provided in a portion of the first extension portion that protrudes into the second extension portion. The second engaging portion of the second guide portion may also be provided within the second extension portion. In this embodiment, the main body housing includes a first extension portion that extends rearward relative to the stator housing portion and protrudes into the second extension portion of the handle housing. Furthermore, the rear second guide portion is provided within the second extension portion. In this manner, by intentionally extending a portion of the main body housing rearward, sliding guidance can be provided at a position closer to the handle portion, thereby further improving operability.

[0014] In one embodiment of the present invention, the impact tool may further include a limiting portion, which is configured to limit the relative movement of the main body shell and the handle shell in the left-right direction when the direction perpendicular to the second axis and corresponding to the extension direction of the grip portion is defined as the up-down direction and the direction perpendicular to the front-back direction and the up-down direction is defined as the left-right direction. The limiting portion may also include a first abutting portion and a second abutting portion that are respectively provided on the main body shell and the handle shell and can abut against each other. The first guide portion and the second guide portion may also be configured at a position above the first axis, and the limiting portion is configured at a position below the first axis. In this case, the limiting portion can effectively limit the rotation of the main body shell and the handle shell around the axis passing through the first guide portion and the second guide portion, thereby suppressing shaking.

[0015] In one embodiment of the present invention, one of the first and second abutting portions can be forced toward the other, allowing for sliding contact therewith. In this case, wobbling can be more effectively suppressed. Furthermore, the first guide portion, the second guide portion, and the restricting portion can more stably guide the sliding movement of the main housing and the handle housing.

[0016] In one aspect of the present invention, the restricting portion may be disposed between the first guide portion and the second guide portion in the front-rear direction. In this case, rattling can be effectively suppressed.

[0017] In one embodiment of the present invention, the main body shell may also include a stator housing portion and a third extension portion, wherein the stator housing portion houses the stator. When the direction perpendicular to the second axis and corresponding to the extension direction of the grip portion is defined as the up and down direction, the third extension portion extends rearward relative to the stator housing portion at a position lower than the first axis and protrudes into the handle shell. In addition, the third extension portion may also have a first abutment portion and be configured to guide the wires extending from the motor. In this case, the third extension portion can be used to reasonably implement a structure for suppressing shaking and a structure for guiding the wires extending from the motor into the handle shell.

[0018] In one embodiment of the present invention, the first abutting portion and the second abutting portion of the restricting portion may also be in contact with each other in a manner that allows for sliding movement. Furthermore, the first elastic member may be positioned vertically below the first and second guide portions, and above the restricting portion. In this case, the first guide portion, the second guide portion, and the restricting portion can more stably guide the sliding movement of the main body housing and the handle housing in the vertical direction. Furthermore, the elastic connection and sliding guidance between the main body housing and the handle housing can be well balanced in the vertical direction.

[0019] In one embodiment of the present invention, at least one of the first engaging portion and the second engaging portion may include a metal portion that slides with the other of the first engaging portion and the second engaging portion. In this case, the first engaging portion and the second engaging portion can slide smoothly.

[0020] In one embodiment of the present invention, the impact tool may further include a movable part, a detector, and a control device. The movable part may also be provided on one side of the main body shell and the handle shell, and may be configured to move as the other side of the main body shell and the handle shell moves relative to each other in the front-to-back direction. The detector may be provided on the side of the main body shell and the handle shell where the movable part is provided, and may be configured to detect the pressing of the top tool on the workpiece by detecting the movement of the movable part. The control device may also be configured to control the drive of the motor based on the detection result of the detector. The movable part and the detector may also be arranged between the first guide portion and the second guide portion in the front-to-back direction.

[0021] When the top tool is pressed against the workpiece, the handle shell elastically connected to the main body shell moves relative to the main body shell forward. That is, the transition from the no-load state to the loaded state corresponds to the relative movement of the handle shell forward. In the impact tool of this method, the relative movement of the other of the main body shell and the handle shell in the front-to-back direction corresponds to the movement of the movable part. Therefore, the detector can appropriately detect the pressing of the top tool on the workpiece (the transition from the no-load state to the loaded state) through the movement of the movable part. Moreover, the control device can control the drive of the motor according to whether the top tool is in the no-load state or the loaded state based on the detection result of the detector. In addition, since the movable part and the detector are arranged at a position where the main body shell and the handle shell can stably move relative to each other in the front-to-back direction, the detection accuracy can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is the right side view of the hammer drill.

[0023] Figure 2 This is a cross-sectional view of a hammer drill.

[0024] Figure 3 It is a perspective view of the main body shell.

[0025] Figure 4 yes Figure 2 A partial enlarged view of .

[0026] Figure 5 It is a three-dimensional image of a hammer drill.

[0027] Figure 6 This is a perspective view of the handle housing with the right half removed.

[0028] Figure 7 yes Figure 4 VII-VII cross-sectional view.

[0029] Figure 8 yes Figure 4 Sectional view taken along line VIII-VIII.

[0030] Figure 9 yes Figure 1 IX-IX cross-sectional view.

[0031] Figure 10 It is a partial perspective view of the handle housing with the right half removed, showing a state in which the movable member is arranged in the most forward position (initial position).

[0032] Figure 11 This is an explanatory diagram of the position detection mechanism when the movable member is arranged in the initial position.

[0033] Figure 12 yesFigure 4 Sectional view of XII-XII.

[0034] Figure 13 It is a partial perspective view of the handle housing with the right half removed, showing a state in which the movable member is arranged in the disconnected position.

[0035] Figure 14 This is an explanatory diagram of the position detection mechanism when the movable member is arranged in the disconnected position.

[0036] [Explanation of Reference Numerals]

[0037] 1: Hammer drill; 2: Motor; 3: Drive mechanism; 11: Main body housing; 12: Gear housing; 121: Cylinder; 125: Support body; 13: Motor housing; 13L, 13R: Split housing; 131: Connecting portion; 133: Stator housing; 135: Bearing housing; 136: Through hole; 141: Upper extension; 146: Lower extension; 147: Opening; 15: Handle housing; 15L, 15R: Split housing; 17: Grip; 171: Trigger; 173: Switch; 18: Base; 181: Cover; 182: Rear wall; 183: Support wall; 184: Upper extension; 186: Lower extension; 187: Battery mounting portion; 188: Front extension; 21: Stator; 23: Rotor; 25: Motor shaft; 251: Bearing; 253: Bearing; 28: Fan; 30: Tool holder; 31: Motion conversion mechanism; 32: Intermediate shaft; 33: Rotating body; 34: Swinging member; 35: Piston cylinder; 36: Cylinder; 37: Impact element; 371: Hammer; 373: Impact rod; 38: Rotation transmission mechanism; 381: First gear; 382: Second gear; 39: Mode change Operation lever; 41: Controller; 43: Acceleration detection unit; 431: Sensor body; 433: Housing; 435: Elastic member; 437: Pin; 45: Position detection mechanism; 451: Movable member; 452: Base; 453: Protrusion; 454: Protrusion; 455: Protrusion; 456: Magnet; 457: Force-applying member; 458: Hall sensor; 459: Circuit board; 461: Support; 462: Support wall; 463: Guide recess; 465: Stopper wall; 467: Cover; 51: Elastic member; 53: Spring-bearing member; 5 9: Corrugated portion; 61: Front guide portion; 611: Guide protrusion; 612: Cover plate; 615: Guide wall; 616: Recess; 62: Rear guide portion; 621: Guide protrusion; 622: Cover plate; 625: Guide wall; 626: Recess; 631: Stop protrusion; 633: Stop wall; 635: Stop wall; 65: Pressing protrusion; 67: Limiting portion; 671: Abutment portion; 672: Abutment surface; 673: Abutment plate; 674: Protrusion; 677: Elastic component; 91: Top tool; 93: Battery; A1: Drive axis; A2: Rotation axis. DETAILED DESCRIPTION

[0038] The following embodiments are described with reference to the accompanying drawings. The following embodiments illustrate a handheld hammer drill 1 as an example of an impact tool and, more specifically, as an example of a drilling tool. The hammer drill 1 is configured to be capable of both linearly driving a tip tool 91 along a predetermined drive axis A1 (hereinafter referred to as an impact operation) and rotating the tip tool 91 about the drive axis A1 (hereinafter referred to as a drilling operation).

[0039] First, the schematic structure of the hammer drill 1 will be described. Figure 1 and Figure 2 As shown, the outer contour of the hammer drill 1 is mainly formed by a main body housing 11 and a handle housing 15. In this embodiment, the main body housing 11 and the handle housing 15 are both made of synthetic resin.

[0040] The main body housing 11 is a long hollow body extending along the drive axis A1. A tool holder 30 is arranged in one end portion of the main body housing 11 in the longitudinal direction (see Figure 2 ). A tip tool 91 is detachably mounted on the tool holder 30. In addition, the motor 2 and the drive mechanism 3 are housed in the main body housing 11.

[0041] The handle housing 15 is elastically connected to the other end of the main body housing 11 in the longitudinal direction (the end on the side opposite to the end where the tool holder 30 is arranged). The handle housing 15 includes a long strip-shaped gripping portion 17 for the user to hold. The gripping portion 17 is away from the main body housing 11 and extends in a direction intersecting the drive axis A1 (in detail, a direction approximately orthogonal). One end of the gripping portion 17 in the longitudinal direction is arranged on the drive axis A1 and has a trigger 171 that the user can press. The other end of the gripping portion 17 is located at a position away from the drive axis A1. When the handle housing 15 as a whole is observed from a direction orthogonal to the drive axis A1 and the longitudinal axis of the gripping portion 17, the handle housing 15 is formed into a ring shape (approximately D-shaped).

[0042] When the user presses the trigger 171 , the motor 2 is driven to perform an impact action and / or a drilling action through the driving mechanism 3 .

[0043] The detailed structure of the hammer drill 1 is described below. In addition, in the following description, for convenience, the extension direction of the drive axis A1 (also referred to as the long axis direction of the main body housing 11, or the axial direction of the top tool 91) is defined as the front-to-back direction of the hammer drill 1. In the front-to-back direction, the side on which the top tool 91 is mounted (the side on which the tool holder 30 is arranged) is defined as the front side of the hammer drill 1, and the opposite side (the side on which the grip 17 is arranged) is defined as the rear side. In addition, the direction perpendicular to the drive axis A1 and corresponding to the extension direction of the grip 17 is defined as the up-down direction. In the up-down direction, the side of one end of the grip 17 on which the trigger 171 is arranged is defined as the upper side, and the opposite side (the end side located at a position away from the drive axis A1) is defined as the lower side. Furthermore, the direction perpendicular to the front-to-back direction and the up-down direction is defined as the left-right direction.

[0044] First, the main body housing 11 and its internal structure will be described.

[0045] like Figure 2 andFigure 3 As shown, in this embodiment, the main housing 11 includes a gear housing 12 and a motor housing 13. The gear housing 12 is a housing that primarily houses the drive mechanism 3. The motor housing 13 is a housing that primarily houses the motor 2. The gear housing 12 and the motor housing 13 are each assembled with internal mechanisms. With the motor housing 13 positioned behind the gear housing 12, they are connected and fixed in the front-to-back direction by screws. The gear housing 12 and the motor housing 13 are connected and fixed together in a manner that prevents relative movement, thereby forming the main housing 11 as a single housing.

[0046] The gear housing 12 and its internal structure will be described below.

[0047] like Figure 2 and Figure 3 As shown, the gear housing 12 is formed as a long cylindrical body as a whole. The gear housing 12 has a cylindrical front end portion (hereinafter referred to as the barrel 121). The tool holder 30 is supported in the barrel 121 in a manner that can rotate around the drive axis A1. The entire portion of the gear housing 12 that is further rearward than the barrel 121 is formed to have a rectangular cross-section and accommodates the drive mechanism 3. In addition, in this embodiment, the drive mechanism 3 is fixedly held in the gear housing 12 while being supported by a metal support body 125.

[0048] like Figure 2 As shown, in this embodiment, the driving mechanism 3 includes a motion conversion mechanism 31 , an impact element 37 and a rotation transmission mechanism 38 .

[0049] The motion conversion mechanism 31 is configured to convert the rotational motion of the motor shaft 25 of the motor 2 into linear motion and transmit the linear motion to the impact element 37. In this embodiment, the motion conversion mechanism 31 includes an intermediate shaft 32, a rotating body 33, a swing member 34, and a piston cylinder 35.

[0050] The intermediate shaft 32 extends in the front-to-back direction parallel to the motor shaft 25 and is supported in a rotatable manner by two bearings retained on the gear housing 12. The rotating body 33 is mounted on the outer periphery of the intermediate shaft 32. The swinging component 34 is mounted on the outer periphery of the rotating body 33 and swings in the front-to-back direction as the rotating body 33 rotates. The piston cylinder 35 is formed into a cylindrical shape with a bottom. The piston cylinder 35 is retained in a cylindrical cylinder 36 in a manner that allows it to slide in the front-to-back direction. The piston cylinder 35 reciprocates in the front-to-back direction as the swinging component 34 swings. In addition, the cylinder 36 is coaxially connected to the rear side of the tool holder 30 and is integrated. The integrated tool holder 30 and cylinder 36 are supported in a rotatable manner around the drive axis A1 by two bearings retained on the gear housing 12.

[0051] The impact element 37 is configured to impact the tip tool 91 (see Figure 1 ), thereby driving the top tool 91 linearly along the drive axis A1. In this embodiment, the impact element 37 includes a hammer 371 and an impact rod 373. The hammer 371 is arranged in a manner that can slide in the front-back direction within the piston cylinder 35. The impact rod 373 is arranged in front of the hammer 371. The space inside the piston cylinder 35 behind the hammer 371 is defined as an air chamber that functions as an air spring.

[0052] When the motor 2 is driven to move the piston cylinder 35 forward, the air in the air chamber is compressed and the internal pressure rises. Therefore, the hammer 371 is pushed forward at high speed and hits the impact rod 373, thereby transmitting kinetic energy to the top tool 91. Accordingly, the top tool 91 is driven in a straight line along the drive axis A1, thereby impacting the workpiece. On the other hand, when the piston cylinder 35 moves backward, the air in the air chamber expands and the internal pressure drops, and the hammer 371 is pulled in backward. In addition, the top tool 91 is pressed by the workpiece and returns to the rear. The motion conversion mechanism 31 and the impact element 37 perform the impact action by repeating the above-mentioned actions.

[0053] The rotation transmission mechanism 38 is configured to transmit the rotational power of the motor shaft 25 to the tool holder 30. The rotation transmission mechanism 38 is a gear reduction mechanism composed of multiple gears, including a first gear 381 and a second gear 382. The first gear 381 is disposed at the front end of the intermediate shaft 32. The second gear 382 is disposed on the outer periphery of the cylinder 36 and meshes with the first gear 381. When the motor 2 is driven, the cylinder 36 and the tool holder 30 rotate integrally about the drive axis A1 via the rotation transmission mechanism 38. Consequently, the top tool 91 held in the tool holder 30 is driven to rotate about the drive axis A1. As described above, the rotation transmission mechanism 38 performs the drilling operation.

[0054] The hammer drill 1 of this embodiment has three operation modes: hammer drill mode, electric hammer mode and drilling mode. The user operates the mode change operation lever 39 (see Figure 3), one of the three modes can be selected. In the hammer drill mode, the motion conversion mechanism 31 and the rotation transmission mechanism 38 are driven to perform impact and drilling actions. In the electric hammer mode, the power transmission in the rotation transmission mechanism 38 is cut off, and only the motion conversion mechanism 31 is driven, so that only the impact action is performed. In the drilling mode, the power transmission in the motion conversion mechanism 31 is cut off, and only the rotation transmission mechanism 38 is driven, so that only the drilling action is performed. A mode switching mechanism is provided in the gear housing 12, and the mode switching mechanism switches the transmission state of the motion conversion mechanism 31 and the rotation transmission mechanism 38 according to the operation of the mode change operating lever 39. Since the structure of the mode switching mechanism itself is well known, its description is omitted here.

[0055] The motor housing 13 and its internal structure are described below. Figure 2 and Figure 3 As shown, the motor housing 13 is formed as a long hollow body extending in the front-to-back direction and accommodates the motor 2. The motor 2 is a brushless motor having a stator 21, a rotor 23 and a motor shaft 25, wherein the motor shaft 25 extends from the rotor 23 and is configured to rotate integrally with the rotor 23. The motor 2 is configured so that the rotation axis A2 of the motor shaft 25 extends parallel to the drive axis A1 (in the front-to-back direction). The front end and the rear end of the motor shaft 25 are supported in a rotatable manner by bearings 251 and 253, respectively. In addition, the front side bearing 251 is supported by the support body 125 of the gear housing 12. The rear side bearing 253 is supported by the motor housing 13 (in detail, the bearing receiving portion 135 described later).

[0056] In this embodiment, the motor housing 13 is arranged along a plane P (see FIG. Figure 7 ) is divided into a left half 13L and a right half 13R. The motor housing 13, which is a single housing, is formed by connecting and fixing the half 13L and 13R in the left-right direction using a plurality of screws.

[0057] In addition, the motor housing 13 includes a connecting portion 131, a stator housing portion 133, and a bearing housing portion 135 in order from the front side. The connecting portion 131 is a portion connected and fixed to the gear housing 12. The connecting portion 131 is formed to have a rectangular cross-section corresponding to the shape of the gear housing 12. A fan 28 fixed to the motor shaft 25 is arranged in the connecting portion 131. The stator housing portion 133 is a portion that houses the stator 21 of the motor 2. The stator housing portion 133 is formed to have a roughly cylindrical shape corresponding to the stator 21, and its diameter is smaller than that of the connecting portion 131. The bearing housing portion 135 is a portion that houses the bearing 253 that supports the rear end of the motor shaft 25. The bearing housing portion 135 is formed to have a cylindrical shape corresponding to the bearing 253, and its diameter is smaller than that of the stator housing portion 133.

[0058] In addition, if Figure 3 and Figure 4 As shown, the motor housing 13 includes an upper extension portion 141 and a lower extension portion 146. The upper extension portion 141 and the lower extension portion 146 protrude rearward from the stator housing 133 and extend in the front-to-back direction above and below the bearing housing 135, respectively. The rear ends of the upper extension portion 141 and the lower extension portion 146 are both located rearward of the rear end of the bearing housing 135. Furthermore, the rear end of the upper extension portion 141 is located rearward of the rear end of the lower extension portion 146. The interior space of the lower extension portion 146 communicates with the interior space of the stator housing 133.

[0059] The upper extension portion 141 mainly functions as a portion that guides the relative movement of the main body shell 11 and the handle shell 15 in the front-to-back direction, which will be described in detail later. The lower extension portion 146 mainly functions as a portion that limits the relative rotation of the main body shell 11 and the handle shell 15. In addition, the lower extension portion 146 defines a path through which the wires (not shown) connected to the motor 2 pass. An opening 147 is provided on the lower wall of the rear end portion of the lower extension portion 146, and the wires are guided into the handle shell 15 (in detail, into the front extension portion 188 described later) through the opening 147.

[0060] The connecting portion 131 of the motor housing 13 having the above structure is fixed to the gear housing 12 and exposed to the outside of the handle housing 15. On the other hand, most of the stator housing 133, the bearing housing 135, the upper extension portion 141, and the lower extension portion 146 are arranged in the handle housing 15 (specifically, the base 18).

[0061] The handle housing 15 and its internal structure are described below.

[0062] like Figure 5 As shown, the handle housing 15 is similar to the motor housing 13, along a plane P (refer to Figure 7 ), is divided into a left-hand half body 15L and a right-hand half body 15R. The handle housing 15 as a single shell is formed by connecting and fixing the half bodies 15L and 15R in the left-right direction using a plurality of screws.

[0063] In addition, if Figure 1 and Figure 2 As shown, the handle housing 15 includes a grip portion 17 and a base portion 18 .

[0064] As described above, the grip portion 17 extends rearwardly away from the rear end portion of the main body housing 11 and in a generally vertical direction, and a trigger 171 is arranged on the front surface side of the upper end portion of the grip portion 17. The upper end portion of the grip portion 17 and the trigger 171 are arranged on the drive axis A1. Inside the grip portion 17, a switch 173 is arranged adjacent to the trigger 171. The switch 173 is normally maintained in the off state and becomes the on state in response to the user's pressing operation on the trigger 171. The switch 173 is connected to the controller 41 via an electric wire (not shown) and outputs a signal indicating the on state or the off state to the controller 41.

[0065] The base 18 connects the grip 17 to the main body housing 11 and forms an annular portion (ring) together with the grip 17. The base 18 includes a cover 181, an upper extension 184, a lower extension 186, and a front extension 188.

[0066] The cover portion 181 is a portion that extends in the front-to-back direction and surrounds a portion of the main body housing 11 in the circumferential direction around the drive axis A1. The cover portion 181 is roughly formed into a rectangular box with a bottom. In more detail, the front end of the cover portion 181 is open, and the rear end of the cover portion 181 is closed by the rear wall 182. The cover portion 181 has a cross-sectional shape that roughly matches the connecting portion 131 of the gear housing 12 and the motor housing 13. The cover portion 181 is arranged behind the connecting portion 131 of the motor housing 13, and accommodates a portion of the stator housing portion 133 of the motor housing 13, the bearing housing portion 135, a portion of the upper extension portion 141, and a portion of the lower extension portion 146.

[0067] In addition, if Figure 2 As shown, an annular bellows portion 59 is interposed between the front end of the cover portion 181 and the rear end of the connecting portion 131 of the motor housing 13. The bellows portion 59 is capable of expanding and contracting in the front-to-back direction. The bellows portion 59 expands and contracts in response to the front-to-back movement of the handle housing 15 relative to the main housing 11, and prevents dust and the like from entering between the main housing 11 and the handle housing 15.

[0068] like Figure 6 As shown, the position detection mechanism 45 is housed in the cover portion 181. The position detection mechanism 45 is configured to detect the relative position of the handle housing 15 with respect to the main body housing 11 in the front-rear direction. The position detection mechanism 45 will be described in detail later.

[0069] like Figure 1 and Figure 2As shown, upper extension 184 is a portion that protrudes rearward from the upper rear end of cover 181 and connects to the upper end of grip 17. Upper extension 184 is cylindrical, and the interior of upper extension 184 communicates with the interior of cover 181 via an opening provided in rear wall 182. The interior of upper extension 184 also communicates with the interior of grip 17. The rear end of upper extension 141 of motor housing 13 protrudes into upper extension 184.

[0070] The lower extension portion 186 is a portion that protrudes forward from the lower end portion of the grip portion 17. The lower extension portion 186 is formed in a rectangular box shape. The interior space of the lower extension portion 186 communicates with the interior space of the grip portion 17.

[0071] The controller 41 is housed in the lower extension 186. Although not shown in detail, the controller 41 includes a control circuit, a three-phase inverter, and a circuit board on which these components are mounted. The control circuit comprises a microcomputer including a CPU, ROM, RAM, a timer, and other components. The control circuit drives the motor 2 via the three-phase inverter. In this embodiment, the controller 41 (control circuit) is configured to control the drive of the motor 2 based on the on / off state of the switch 173 and the detection results of various sensors, as described in detail below.

[0072] In addition, a battery mounting portion 187 is provided at the lower end portion of the lower extension portion 186. The battery 93 is mounted on the battery mounting portion 187 in a detachable manner. The battery 93 is a power source for supplying power to the motor 2, the controller 41, etc. and can be repeatedly charged, and is also called a battery pack. The battery mounting portion 187 has: a rail that can be slidably engaged with the guide groove of the battery 93; and a terminal that can be electrically connected to the terminal of the battery 93. In addition, since the structure of the battery 93 and the battery mounting portion 187 is well known, detailed description and illustration are omitted. The battery mounting portion 187 is connected to the controller 41 via an electric wire not shown. The battery mounting portion 187 and the controller 41 are both provided on the lower extension portion 186 and are located near each other, so wiring is easy.

[0073] Front extension 188 connects lower extension 186 and cover 181. Front extension 188 is cylindrical, extending generally upward from the front end of lower extension 186 and connecting to the lower rear end of cover 181. The interior of front extension 188 communicates with both the interiors of lower extension 186 and cover 181. The lower end of lower extension 146 of motor housing 13 protrudes into the interior of the upper end of front extension 188.

[0074] like Figure 4 and Figure 6As shown, the acceleration detection unit 43 is housed in the front extension 188. More specifically, the acceleration detection unit 43 is disposed in the lower end portion of the front extension 188 (in the lower end portion of the base 18 connecting the lower end portion of the grip 17 to the main body housing 11).

[0075] The structure of the acceleration detection unit 43 is described below. The acceleration detection unit 43 includes a housing 433 and a sensor body 431. The housing 433 is formed in a rectangular box shape. The sensor body 431 is housed within the housing 433 and molded integrally with the housing 433. Furthermore, the sensor body 431 is connected to the controller 41 via electrical wiring (not shown). As described above, the controller 41 is housed in the lower extension 186 connected to the front extension 188, making wiring easier.

[0076] Although detailed illustrations are omitted, the sensor body 431 includes an acceleration sensor, a microcomputer including a CPU, ROM, RAM, etc., and a circuit board on which these components are mounted. The acceleration sensor detects acceleration as information (physical quantity, indicator) corresponding to the rotational state of the handle housing 15 rotating about the drive axis A1 (and therefore the rotational state of the main body housing 11). In addition, the acceleration detection unit 43 is arranged directly below the drive axis A1. At this position, the rotation of the handle housing 15 and the main body housing 11 about the drive axis A1 can be captured as movement in the left-right direction. Therefore, a well-known acceleration sensor capable of detecting acceleration in the left-right direction is mounted on the sensor body 431. In the hammer drill 1, the acceleration detection unit 43 is arranged at the lower end of the base 18 (front extension 188), that is, the position farthest from the drive axis A1, so that the acceleration sensor can detect acceleration in the left-right direction with high precision.

[0077] The microcomputer of the sensor body 431 determines whether the acceleration detected by the acceleration sensor exceeds a predetermined threshold value. Then, when the acceleration exceeds the threshold value, a specific signal (hereinafter referred to as an error signal) is output to the controller 41 (refer to Figure 7 The acceleration exceeding the threshold value corresponds to a state in which the hammer drill 1 is excessively rotated about the drive axis A1. Typically, this state occurs when the tip tool 91 becomes stuck during the drilling operation, rendering the tool holder 30 unable to rotate (also known as a blocking state), resulting in excessive reaction torque acting on the handle housing 15 and the main body housing 11.

[0078] Alternatively, the sensor body 431 may not include a microcomputer, but may directly output a signal indicating the detection result of the acceleration sensor to the controller 41, and the controller 41 may perform the above-mentioned determination. Controlling the operation of the hammer drill 1 based on the signal output from the sensor body 431 will be described later.

[0079] Furthermore, the acceleration detection unit 43 is supported on the front extension 188 via elastic members 435. More specifically, multiple elastic members 435 are embedded in the housing 433 and sandwiched between the housing 433 and the left side wall of the front extension 188, as well as between the housing 433 and the right side wall of the front extension 188. In this embodiment, two pairs of elastic members 435 (i.e., four elastic members 435 in total) are provided: one pair is embedded in the left and right sides of the upper end of the housing 433, and the remaining pair is embedded in the left and right sides of the lower end of the housing 433. A pin 437 is inserted into each pair of elastic members 435. The pins 437 are supported at both ends by the left and right sides of the front extension 188, and extend in the left-right direction within the front extension 188. This elastic support structure allows the acceleration detection unit 43 to be supported on the handle housing 15 in a manner that allows for movement in all directions, including front-to-back, up-down, and left-to-right directions.

[0080] As described above, in this embodiment, the acceleration detection unit 43 is housed in the base 18 (specifically, the front extension 188), which connects the lower end of the grip 17, located farther from the drive axis A1 (i.e., the end located further from the main housing 11), to the main housing 11. This allows for a convenient placement of the acceleration detection unit 43 without increasing the overall size of the hammer drill 1 in the direction extending (forward and backward) along the drive axis A1 or in a direction intersecting the drive axis A1.

[0081] Furthermore, as described above, the acceleration detection unit 43 is supported by the elastic member 435 , thereby effectively protecting the acceleration sensor, which is a precision device, from vibration.

[0082] In this embodiment, the handle housing 15 is elastically connected to the main body housing 11 and can move in the front-rear direction relative to the main body housing 11. The elastic connection structure between the main body housing 11 and the handle housing 15 will be described below.

[0083] like Figure 4 As shown, an elastic member 51 is interposed between the main body housing 11 and the handle housing 15 in the front-to-back direction. The elastic member 51 urges the main body housing 11 and the handle housing 15 in a direction away from each other (i.e., forward and backward, respectively). The elastic member 51 is a compression coil spring.

[0084] More specifically, the elastic member 51 is positioned between the rear end of the motor shaft 25 (specifically, the bearing 253) and the support wall 183, which is provided in front of the rear wall 182 of the handle housing 15. As described above, the bearing housing 135 of the motor housing 13 is cylindrical and has a through-hole 136 extending in the front-to-back direction along the rotation axis A2. The bearing (specifically, a ball bearing) 253, which supports the rear end of the motor shaft 25, is inserted into the through-hole 136. Furthermore, the spring receiving member 53 is positioned behind the bearing 253. The front portion of the spring receiving member 53 is inserted into the through-hole 136, while the rear portion of the spring receiving member 53 protrudes rearward from the through-hole 136. The front end of the spring receiving member 53 abuts the rear end of the bearing 253 (specifically, the outer ring of the ball bearing). One end portion of the elastic member 51 is fitted into the rear end portion of the spring receiving member 53 , and the other end portion of the elastic member 51 is in contact with the front end surface of the support wall 183 .

[0085] With this arrangement, the elastic member 51 urges the main body housing 11 forward via the spring receiving member 53 , the bearing 253 , and the motor shaft 25 , and urges the handle housing 15 rearward via the support wall 183 .

[0086] Furthermore, the hammer drill 1 has a guide structure for guiding the handle housing 15 to move relative to the main body housing 11 in the front-rear direction. The guide structure will be described below.

[0087] In this embodiment, if Figure 4 、 Figure 7 and Figure 8 As shown, the hammer drill 1 has a pair of front guides 61 and a pair of rear guides 62 that are separated in the front-to-back direction. The pair of front guides 61 are arranged symmetrically (symmetrically with respect to the plane P). The front guides 61 are each composed of a set of engaging portions, which are respectively provided on the main body housing 11 and the handle housing 15 and engage with each other in a manner that allows sliding in the front-to-back direction. Similarly, the pair of rear guides 62 are also arranged symmetrically. The rear guides 62 are each composed of a set of engaging portions, which are respectively provided on the main body housing 11 and the handle housing 15 and engage with each other in a manner that allows sliding in the front-to-back direction. In addition, in this embodiment, the front guides 61 and the rear guides 62 have substantially the same structure. The detailed structure of the front guides 61 and the rear guides 62 will be described below.

[0088] like Figure 3 、 Figure 6 and Figure 7 As shown, the front guide portion 61 is composed of a guide protrusion 611 and recesses 616 formed on two guide walls 615 .

[0089] The guide protrusions 611 are provided at the upper end of the stator housing 133 of the motor housing 13 (i.e., above the stator 21). Each guide protrusion 611 protrudes leftward or rightward toward the left or right side wall of the handle housing 15. The guide protrusions 611 are formed into a rectangular parallelepiped shape that is elongated in the front-to-back direction. The surface of the guide protrusions 611 is covered by a metal cover plate 612.

[0090] Two guide walls 615 are provided at the upper front end of the cover portion 181 of the handle housing 15. Each guide wall 615 protrudes inward (plane P) from the sidewall of the cover portion 181 and has a recess 616 having a shape that generally matches the cross-sectional shape of the guide protrusion 611. The two guide walls 615 are spaced apart in the front-to-back direction so that the recesses 616 are aligned along a straight line extending in the front-to-back direction. The guide protrusion 611 is disposed within the recesses 616 of the two guide walls 615 and is slidable in the front-to-back direction.

[0091] Likewise, Figure 3 、 Figure 6 and Figure 8 As shown, each rear guide portion 62 is composed of a guide protrusion 621 and a recess 626 formed on two guide walls 625 .

[0092] The guide protrusions 621 are provided at the rear end of the upper extension 141 of the motor housing 13. Each guide protrusion 621 protrudes to the left or right side, toward the left or right side wall of the handle housing 15. Two guide walls 625 are arranged within the upper extension 184 of the handle housing 15, spaced apart in the front-to-back direction. The guide protrusions 621 and guide walls 625 have substantially the same structure as the guide protrusions 611 and guide walls 615. Specifically, the guide protrusions 621 are formed into a roughly rectangular parallelepiped shape, and their surfaces are covered by a metal cover plate 622. Furthermore, the guide plate 622 is the same metal component (common component) as the cover plate 612 of the guide protrusions 611. Each guide wall 625 protrudes inward (plane P) from the sidewalls of the upper extension 184 and has a recess 626. The guide protrusions 621 are arranged within the recesses 626 of the two guide walls 625, allowing them to slide in the front-to-back direction.

[0093] By the above structure, the main body housing 11 (motor housing 13) and the handle housing 15 are slidably guided in the front-back direction at two different positions in the front-back direction. Figure 4As shown, the front guide portion 61 and the rear guide portion 62 are arranged above the rotation axis A2 of the motor shaft 25 in the vertical direction. Furthermore, the rear guide portion 62 is arranged slightly above the front guide portion 61, but the lower end of the rear guide portion 62 is located below the upper end of the front guide portion 61. Therefore, the main body housing 11 (motor housing 13) and the handle housing 15 are guided in the front-to-back direction at positions that are substantially the same in the vertical direction and spaced apart in the front-to-back direction.

[0094] Furthermore, the hammer drill 1 has a structure for defining the rearmost position and the frontmost position of the handle housing 15 relative to the main body housing 11. Figure 3 and Figure 6 As shown, a pair of left and right stopper protrusions 631 are provided on the upper extension portion 141 of the main body housing 11. Meanwhile, a pair of left and right stopper walls 633 and a pair of left and right stopper walls 635 (only the left stopper walls 633 and 635 are shown) are provided on the upper extension portion 184 of the handle housing 15. The stopper protrusions 631, stopper walls 633, and stopper walls 635 are all arranged between the front guide portion 61 and the rear guide portion 62 in the front-to-back direction.

[0095] Each stop protrusion 631 protrudes to the left or right side toward the left side wall or the right side wall of the handle housing 15. The stop wall 633 and the stop wall 635 are respectively extended from the side wall of the upper extension portion 184 to the inner side (plane P, reference Figure 7 The stopper wall 635 is arranged at a distance behind the stopper wall 633. The distance between the stopper wall 635 and the stopper wall 633 in the front-to-back direction is greater than the length of the stopper protrusion 631 in the front-to-back direction.

[0096] The stop protrusion 631 is arranged between the stop wall 633 and the stop wall 635 in the front-to-back direction. The stop protrusion 631 and the stop wall 633 abut against each other, thereby defining the rearmost position of the handle housing 15. The front surface of the stop protrusion 631 and the rear surface of the stop wall 633 each function as a pair of abutting surfaces that can abut against each other. In addition, the stop protrusion 631 and the stop wall 635 define the frontmost position of the handle housing 15 by abutting against each other. The rear surface of the stop protrusion 631 and the front surface of the stop wall 635 each function as a pair of abutting surfaces that can abut against each other.

[0097] As described above, the handle housing 15 is always urged rearward relative to the main body housing 11 by the elastic member 51. Therefore, the handle housing 15 is maintained at the rearmost position (also referred to as the initial position) where the rear surface of the stopper wall 633 abuts the front surface of the stopper protrusion 631. Figure 2 The position shown is the rearmost position (initial position) of the handle housing 15 .

[0098] During the execution of the impact operation, a large vibration in the front-rear direction is generated on the main body case 11 by driving the tip tool 91 along the driving axis Al. In contrast, the main body case 11 and the handle case 15 connected via the elastic member 51 slide on the front side guide portion 61 and the rear side guide portion 62 relative to each other and move in the front-rear direction relative to each other, whereby the transmission of the vibration in the front-rear direction to the handle case 15 can be effectively suppressed.

[0099] As in the present embodiment, the front side guide portion 61 and the rear side guide portion 62 arranged at intervals in the front-rear direction can improve the dimensional accuracy as compared with a plurality of guide portions arranged at intervals in the circumferential direction of the main body case 11 and the handle case 15. Therefore, the sliding of the main body case 11 and the handle case 15 can be guided stably with high accuracy in the front-rear direction.

[0100] In particular, in the present embodiment, the front side guide portion 61 is arranged inside the cover portion 181 radially outward of the stator 21 (more specifically, above the stator 21). In this way, by providing the front side guide portion 61 in the vicinity of the stator 21 and the rotor 23 which are heavy, the stabilization of the sliding is achieved. On the other hand, the rear side guide portion 62 is provided inside the upper side extension portion 184 of the handle case 15, that is, is provided to a portion extending in the front-rear direction between the stator housing portion 133 and the upper end portion of the grip portion 17. Also, by this, the upper side extension portion 141 can be provided protruding into the upper side extension portion 184 regardless of whether or not any component is housed in the main body case 11 (the motor case 13). In this way, by intentionally extending a portion of the main body case 11 to the rear side, the guide can be performed at a position closer to the grip portion 17, whereby the improvement of the operability is achieved.

[0101] Further, in the present embodiment, the rectangular guide protrusions 611, 621 and the two rectangular recesses 616, 626 respectively engage with each other, and three surfaces of the guide protrusions 611, 621 and three surfaces of each of the recesses 616, 626 respectively contact, and move relative to each other in the front-rear direction in this state. Therefore, particularly stable sliding is achieved. In addition, the portions including the sliding surfaces of the guide protrusions 611, 621 are respectively formed by the metal-made cover plates 612, 622. Therefore, the guide protrusions 611, 621 can respectively slide smoothly relative to the recesses 616, 626. Further, in the present embodiment, the guide walls 615, 625 are formed of a material different from metal (more specifically, synthetic resin). Therefore, the guide protrusions 611, 621 and the recesses 616, 626 are prevented from being fused to each other accompanying the sliding, and particularly, smooth sliding is achieved.

[0102] Furthermore, as Figure 4 and Figure 9As shown, in this embodiment, the hammer drill 1 includes a restricting portion 67 in addition to the front guide portion 61 and the rear guide portion 62. The restricting portion 67 is configured to restrict the left-right relative movement of the main body housing 11 and the handle housing 15 at a position relatively farther from the front guide portion 61 and the rear guide portion 62, below the rotation axis A2 of the motor shaft 25. Furthermore, the restricting portion 67 is disposed between the front guide portion 61 and the rear guide portion 62 in the front-to-back direction.

[0103] like Figure 3 、 Figure 6 and Figure 9 As shown, the limiting portion 67 is composed of a set of abutment portions, which are respectively provided on the main body housing 11 and the handle housing 15, and limit the movement of the handle housing 15 in the left and right directions relative to the main body housing 11 by abutting against each other. More specifically, the limiting portion 67 is composed of an abutment portion 671 provided on the lower side extension portion 146 of the main body housing 11 and a pair of abutment plates 673.

[0104] The contact portion 671 is provided at a portion of the lower extension portion 146 that protrudes into the upper end portion of the front extension portion 188 of the handle housing 15 . The left and right sides of the contact portion 671 function as a pair of contact surfaces 672 .

[0105] A pair of abutment plates 673 are disposed at the upper end of the front extension portion 188 of the handle housing 15. The abutment plates 673 are formed by bending the two longitudinal ends of a metal rectangular thin plate in the same direction and are flexible. The two ends of the abutment plates 673 are embedded in two protrusions 674 provided on the left or right wall of the front extension portion 188, and the abutment plates 673 are supported by the protrusions 674 while allowing slight bending in the left and right directions. In addition, an elastic member 677 is sandwiched between each abutment plate 673 and the left or right wall of the front extension portion 188. In this embodiment, a synthetic resin foam (so-called sponge) formed into a rectangular parallelepiped is used as the elastic member 677. The pair of abutment plates 673 are respectively urged toward the abutment portion 671 by the elastic member 677 at all times, abutting against the pair of abutment surfaces 672.

[0106] With the above structure, the limiting portion 67 can limit the left-right movement of the handle housing 15 relative to the main body housing 11. Accordingly, the limiting portion 67 can effectively limit the relative rotation of the main body housing 11 and the handle housing 15 around the axis passing through the front guide portion 61 and the rear guide portion 62, thereby suppressing shaking.

[0107] Furthermore, because the abutment plate 673 can slide relative to the abutment surface 672, the restricting portion 67 also functions as a guide portion for guiding the sliding of the handle housing 15 relative to the main body housing 11 in the front-to-back direction. That is, in this embodiment, the three guide portions can stably guide the sliding of the main body housing 11 and the handle housing 15. In particular, as described above, the restricting portion 67 is relatively far from the front guide portion 61 and the rear guide portion 62 in the vertical direction and is located between the front guide portion 61 and the rear guide portion 62 in the front-to-back direction. Therefore, the addition of the restricting portion 67 can achieve the excellent effect of suppressing shaking and stabilizing the sliding guidance.

[0108] Furthermore, as described above, the elastic member 51, which urges the main body housing 11 and the handle housing 15 away from each other, is located on the rotation axis A2 of the motor shaft 25. Specifically, the elastic member 51 is positioned vertically below the front guide portion 61 and the rear guide portion 62 and above the restricting portion 67. Therefore, the elastic connection and sliding guidance of the main body housing 11 and the handle housing 15 are well balanced in the vertical direction.

[0109] Next, the detailed structure of the position detection mechanism 45 will be described.

[0110] like Figures 10-12 As shown, in this embodiment, the position detection mechanism 45 is installed inside the cover portion 181 of the handle housing 15. The position detection mechanism 45 includes a movable member 451, a biasing member 457, and a Hall sensor 458.

[0111] The movable member 451 is formed into a generally T-shape, comprising a linearly extending elongated base 452 and a protrusion 453 protruding from the approximate center of the base 452. The movable member 451 is a single component made of synthetic resin. A spring-supporting protrusion 454 is provided at one end of the base 452 in the longitudinal direction. A magnet 456 is fixed to the protrusion 453.

[0112] The movable member 451 is supported in the cover portion 181 of the handle housing 15 so as to be movable in the front-rear direction relative to the handle housing 15. More specifically, a support portion 461 is provided on the left side wall of the cover portion 181. The support portion 461 is arranged behind the guide wall 615 of the front guide portion 61 and in front of the guide wall 625 of the rear guide portion 62. The support portion 461 is formed by extending from the left side wall toward the inner side ( Figure 12The illustrated flat surface P) is constituted by a plurality of wall portions protruding. The support portion 461 has two guide recesses 463 provided to two support walls 462 arranged at intervals in the front-rear direction. The two guide recesses 463 are arranged on a straight line extending in the front-rear direction, each having a shape substantially matching the cross-sectional shape of the base portion 452 of the movable member 451.

[0113] The movable member 451 is supported by the support wall 462 in a state where the base portion 452 is arranged within the two guide recesses 463, and is able to slide linearly in the front-rear direction with respect to the support wall 462. Further, the movable member 451 is arranged such that the spring-receiving protrusion 454 of the base portion 452 protrudes rearward, and the convex portion 453 of the movable member 451 protrudes downward. In addition, the magnet 456 is exposed from the left side surface of the convex portion 453. Although detailed illustration is omitted, a protrusion 455 protruding to the left side is provided at the rear end portion of the base portion 452 (refer to FIG. 6). Figure 11 ) The protrusion 455 abuts against the rear surface of the rear one of the two support walls 462 of the movable member 451, whereby the movable member 451 is prohibited from further moving forward. That is, the rear one of the support walls 462 defines the forwardmost position of the movable member 451.

[0114] The biasing member 457 is supported by the support portion 461 rearward of the movable member 451. The biasing member 457 is a compression coil spring. One end portion of the biasing member 457 is held by the spring-receiving protrusion 454 of the rear end portion of the base portion 452. The other end portion of the biasing member 457 abuts against the stop wall 465 of the support portion 461. With this arrangement, the biasing member 457 always biases the movable member 451 forward, and the movable member 451 is held at the above-described forwardmost position (also referred to as the initial position) in a state where no external force is applied rearward (hereinafter referred to as the initial state).

[0115] The Hall sensor 458 is a known sensor having a Hall element. The Hall sensor 458 is mounted on a circuit substrate 459, which is arranged on the left side of the movable member 451 in such a manner that the Hall sensor 458 faces the magnet 456, and is fixed to the support portion 461 by a screw. The Hall sensor 458 is electrically connected to the controller 41 via an electric wire not shown, and is configured to output a specific signal (an ON signal) to the controller 41 when the magnet 456 is arranged within a prescribed detection range.

[0116] Further, as Figure 6 and 12As shown, a thin plate-shaped cover plate 467 is disposed on the right side of the movable member 451 and is fixed to the support portion 461 by a screw. The cover plate 467 covers a portion of the right side surface of the movable member 451. The cover plate 467 is in partial contact with the movable member 451, allowing the movable member 451 to slide in the front-rear direction and preventing the movable member 451 from coming off to the right side from the guide recess 463. In addition, the cover plate 467 is made of aluminum. By employing such a cover plate 467, the assembly of the movable member 451 can be easily performed, and a reasonable structure capable of maintaining the movable member 451 without affecting the magnet 456 can be achieved.

[0117] The operation of the position detection mechanism 45 will be described below.

[0118] As shown in Figure 3 , a pressing protrusion 65 is provided on the main body case 11, which abuts against the movable member 451 to move the movable member 451. In more detail, the pressing protrusion 65 protrudes rearward from the upper left end portion of the stator housing portion 133 of the motor case 13 (in detail, the rear end of the left-side stop protrusion 631).

[0119] When the handle case 15 is located at the initial position (the rearmost position) relative to the main body case 11, as shown in Figure 10 and Figure 11 , the movable member 451 is held at the initial position (the foremost position). At this time, the front end of the base portion 452 of the movable member 451 is slightly separated rearward from the pressing protrusion 65 of the main body case 11. In addition, the pressing protrusion 65, the movable member 451, and the urging member 457 are disposed on a straight line extending in the front-rear direction. In addition, the recess 616 of the front-side guide portion 61 is also disposed on this straight line. When the movable member 451 is at the initial position, the magnet 456 faces the Hall sensor 458 on the right side of the Hall sensor 458 (refer to Figure 12 ), and is located within the detection range of the Hall sensor 458. Therefore, the Hall sensor 458 outputs an on signal to the controller 41.

[0120] On the other hand, when the handle case 15 is moved forward relative to the main body case 11 from the initial position, as shown in Figure 13 and Figure 14 , the pressing protrusion 65 of the main body case 11 abuts against the front end of the base portion 452 of the movable member 451, causing the movable member 451 to move rearward against the force of the urging member 457. When the handle case 15 reaches a prescribed position forward of the initial position relative to the main body case 11, the movable member 451 moves to a prescribed position rearward of the initial position. Along with this, the magnet 456 comes out of the detection range of the Hall sensor 458, and the output of the on signal is stopped.

[0121] Furthermore, the predetermined position of the handle housing 15 at this time (hereinafter referred to as the disconnected position) is set slightly behind the frontmost position within the movable range of the handle housing 15. Similarly, the predetermined position of the movable member 451 (hereinafter referred to as the disconnected position) is set slightly ahead of the rearmost position within the movable range of the movable member 451. When the movable member 451 is between the disconnected position and the rearmost position, the Hall sensor 458 does not output an on signal.

[0122] As described above, the Hall sensor 458 can detect the position of the movable member 451, which moves linearly as the handle housing 15 moves relative to the main housing 11, via the magnet 456. In other words, the Hall sensor 458 can detect the relative position of the handle housing 15 relative to the main housing 11. The detection result of the Hall sensor 458 is used by the controller 41 to control the drive of the motor 2, which will be described in detail later.

[0123] Furthermore, in this embodiment, as described above, both the movable member 451 and the Hall sensor 458 of the position detection mechanism 45 are disposed on the handle housing 15. If the movable member 451 is disposed on one of the main housing 11 and the handle housing 15, and the Hall sensor 458 is disposed on the other, dimensional variations between the main housing 11 and the handle housing 15 can cause the positional relationship between the movable member 451 and the Hall sensor 458 to differ from the intended setting, potentially leading to erroneous detection by the Hall sensor 458. In contrast, by disposing both the movable member 451 and the Hall sensor 458 on the same handle housing 15 as in this embodiment, the positional relationship between the movable member 451 and the Hall sensor 458 is more stable, thereby reducing the possibility of erroneous detection. In particular, in this embodiment, by disposing the movable member 451 and the Hall sensor 458 on the handle housing 15 rather than the main housing 11, they are also protected from vibration.

[0124] Furthermore, the movable member 451 and the Hall sensor 458 are mounted within the handle housing 15 within the cover portion 181 that circumferentially surrounds the rear portion of the motor housing 13. This prevents the main housing 11 and the handle housing 15 from being oversized in the front-to-back direction, thereby enabling a rational arrangement of the movable member 451 and the Hall sensor 458. Furthermore, by employing a movable member 451 that moves linearly in the front-to-back direction between the cover portion 181 and the motor housing 13 (specifically, the upper extension portion 141), radial oversizing can be suppressed.

[0125] Further, the movable member 451 and the Hall sensor 458 are located between the front side guide portion 61 and the rear side guide portion 62 in the front-rear direction. Further, the movable member 451 and the Hall sensor 458 are located at substantially the same positions as the front side guide portion 61 and the rear side guide portion 62 in the up-down direction. That is, the movable member 451 and the Hall sensor 458 are arranged at positions where the main body case 11 and the handle case 15 are relatively moved most stably in the front-rear direction. Thereby, further improvement of detection accuracy is achieved.

[0126] Further, as described above, the pressing protrusion 65, the movable member 451, and the urging member 457 are arranged on one straight line extending in the front-rear direction, and therefore, the pressing protrusion 65 can move the movable member 451 linearly with high accuracy. On the other hand, the magnet 456 as a detection object of the Hall sensor 458 is attached to the movable member 451 at a position deviated from the straight line. Thereby, the arrangement position of the Hall sensor 458 can be set more freely.

[0127] Further, in the present embodiment, the Hall sensor 458 is configured to detect the magnet 456 arranged in the detection range as described above. Instead of this, the Hall sensor 458 can be able to distinguish the S pole and the N pole of the magnet 456. In this case, for example, the magnet 456 is attached to the movable member 451 with the N pole located at the front side and the S pole located at the rear side. The Hall sensor 458 detects the S pole when the movable member 451 is located between the initial position and the prescribed position (excluding the prescribed position), and detects the N pole when the movable member 451 is located between the prescribed position and the rearmost position. Further, the Hall sensor 458 can output different signals to the controller 41 when detecting the S pole of the magnet 456 and when detecting the N pole of the magnet 456. In this case, the Hall sensor 458 can also detect the position of the movable member 451 via the magnet 456, and further detect the relative position of the handle case 15 with respect to the main body case 11.

[0128] The driving control of the motor 2 by the controller 41 will be described below.

[0129] In the present embodiment, the controller 41 (more specifically, the control circuit) is configured to perform so-called soft no-load control. The soft no-load control refers to a drive control method in which, in a case where the switch 173 is in the on state, the rotational speed of the motor 2 is limited to be below a predetermined lower rotational speed (hereinafter, referred to as an initial rotational speed) in a no-load state, whereas the rotational speed of the motor 2 is allowed to exceed the initial rotational speed in a load state. Further, the no-load state refers to a state in which no load is applied to the tip tool 91, and the load state refers to a state in which a load is applied to the tip tool 91. According to the soft no-load control, it is possible to reduce unnecessary power consumption of the motor 2 in the no-load state.

[0130] In the present embodiment, the determination of the no-load state and the load state in the soft no-load control uses the detection result of the position detection mechanism 45 (more specifically, the Hall sensor 458). If the tip tool 91 is pressed against a workpiece, the handle housing 15 that is elastically connected to the main housing 11 moves forward with respect to the main housing 11. That is, the relative movement of the handle housing 15 in the forward direction, and further the linear movement of the movable member 451 in the rearward direction correspond to the shift from the no-load state to the load state. Therefore, the Hall sensor 458 can appropriately detect the pressing of the tip tool 91 against the workpiece (that is, the shift from the no-load state to the load state) by the movement of the movable member 451 (more specifically, whether the magnet 456 is detected). In particular, in the present embodiment, by the structure of the movable member 451 and the Hall sensor 458 as described above, the Hall sensor 458 can detect the shift from the no-load state to the load state with high precision.

[0131] More specifically, in the no-load state, the handle housing 15 and the movable member 451 are respectively disposed at the initial positions (the rearmost position and the foremost position) by the urging force of the elastic member 51. Therefore, the Hall sensor 458 detects the magnet 456, and the position detection mechanism 45 outputs an on signal. In a case where the output from the position detection mechanism 45 is on, the controller 41 determines that the motor 2 is in the no-load state. When the switch 173 becomes the on state from the off state, the controller 41 starts the drive of the motor 2.

[0132] Further, in the present embodiment, the rotational speed set by the speed change dial (not shown) is used as the rotational speed corresponding to the maximum operation amount of the trigger 171 (i.e., the highest rotational speed). Also, the rotational speed of the motor 2 is set in accordance with the highest rotational speed and the actual operation amount (depression amount) of the trigger 171. In the no-load state, if the rotational speed calculated in accordance with the highest rotational speed and the operation amount of the trigger 171 is below the initial rotational speed, the controller 41 sets the calculated rotational speed directly as the rotational speed of the motor 2. On the other hand, in the case where the calculated rotational speed exceeds the initial rotational speed, the controller 41 sets the initial rotational speed as the rotational speed of the motor 2.

[0133] Along with the driving of the motor 2, the drive mechanism 3 is driven in accordance with the operation mode selected via the mode change lever 39, and at least one of the impact operation and the drilling operation is performed.

[0134] If the user presses the tip tool 91 against the workpiece while holding the grip portion 17, the handle case 15 moves forward from the initial position while compressing the elastic member 51 relative to the main body case 11. At this time, the front side guide portion 61 and the rear side guide portion 62 guide the relative sliding of the main body case 11 and the handle case 15 in the front-rear direction. With the relative movement of the handle case 15 in the forward direction, the movable member 451 is pressed by the pressing protrusion 65 and moves rearward from the initial position. When the handle case 15 and the movable member 451 reach the disengagement position, the Hall sensor 458 stops outputting the on signal. The controller 41 recognizes the transition from the no-load state to the load state from the change in the output from the Hall sensor 458 from on to off.

[0135] If the controller 41 recognizes the transition to the load state, the motor 2 is driven at the rotational speed calculated in accordance with the highest rotational speed and the operation amount of the trigger 171. Unlike in the no-load state, even if the calculated rotational speed exceeds the initial rotational speed, the controller 41 does not limit the rotational speed.

[0136] Further, in the case where the output from the Hall sensor 458 is off (i.e., in the load state) and the switch 173 is in the on state, the controller 41 starts the driving of the motor 2 at the rotational speed calculated in accordance with the highest rotational speed and the operation amount of the trigger 171.

[0137] In any case, when the cocking operation of the trigger 171 is released and the switch 173 is in the off state, the controller 41 stops the driving of the motor 2.

[0138] In addition, the controller 41 can also be configured to limit the rotation speed of the motor 2 to below the initial rotation speed when it is recognized that the switch 173 is in the on state and the output from the Hall sensor 458 changes from the off state to the on state (that is, the relative movement of the handle housing 15 and the movable part 451 from the off position to the initial position, the transition from the loaded state to the unloaded state). In this case, for example, the controller 41 monitors the duration of the on state of the Hall sensor 458 after the change by a timer. Moreover, the rotation speed of the motor 2 is limited to below the initial rotation speed only when the on state lasts for the entire specified time. This is to reliably distinguish between the temporary change of the main body housing 11 to the on state when it vibrates in conjunction with the processing operation and the change from the loaded state to the unloaded state.

[0139] Furthermore, in the present embodiment, the controller 41 is configured to perform control based on the detection results of the acceleration detection unit 43 (more specifically, the acceleration sensor) in addition to performing no-load soft start control. More specifically, the controller 41 stops driving the motor 2 when it recognizes an error signal output from the acceleration detection unit 43. As described above, the error signal indicates a rotational state in which the main body housing 11 rotates excessively around the drive axis A1. Therefore, when the controller 41 recognizes the error signal, it stops driving the motor 2 to prevent the motor 2 from rotating further. Alternatively, in addition to the error signal, the controller 41 may also determine whether excessive rotation has occurred based on other information (for example, the torque acting on the top tool 91, the driving current of the motor 2).

[0140] The following shows the correspondence between the components of the above-mentioned embodiment and the components of the present invention. However, the components of the embodiment are merely examples and do not limit the components of the present invention.

[0141] The hammer drill 1 is an example of an "impact tool". The motor 2, the stator 21, the rotor 23, the motor shaft 25, and the rotation axis A2 are examples of the "motor", the "stator", the "rotor", the "motor shaft", and the "first axis", respectively. The drive mechanism 3 and the drive axis A1 are examples of the "drive mechanism" and the "second axis", respectively. The top tool 91 is an example of a "top tool". The main body housing 11 is an example of a "main body housing". The handle housing 15 and the grip portion 17 are examples of the "handle housing" and the "grip portion", respectively. The elastic component 51 is an example of an "elastic component". The front guide portion 61 and the rear guide portion 62 are examples of the "first guide portion" and the "second guide portion", respectively. The guide protrusion 611 and the guide protrusion 621 are examples of the "first engaging portion", respectively. The recess 616 and the recess 626 are examples of the "second engaging portion", respectively.

[0142] The stator housing portion 133 is an example of a "stator housing portion". The upper extension portion 141 is an example of a "first extension portion". The cover portion 181 and the upper extension portion 184 are examples of a "cover portion" and a "second extension portion", respectively. The limiting portion 67 is an example of a "limiting portion". The abutment portion 671 (abutment surface 672) and the abutment plate 673 are examples of a "first abutment portion" and a "second abutment portion", respectively. The lower extension portion 146 is an example of a "third extension portion". The cover plate 612 is an example of a "metal portion".

[0143] The above-described embodiments are merely examples, and the impact tool according to the present invention is not limited to the hammer drill 1 illustrated. For example, the following modifications may be implemented. Furthermore, at least one of these modifications may be employed in combination with the hammer drill 1 illustrated in the embodiment and any of the inventions described in the respective claims.

[0144] In the above embodiment, a hammer drill 1 is used as an example of an impact tool. However, the present invention can also be applied to impact tools other than the hammer drill 1 (for example, a rotary hammer). Furthermore, the hammer drill 1 may have only two operating modes: a rotary hammer mode and a drilling mode. Depending on the impact tool to which the present invention is applied, the motor 2 and drive mechanism 3 can be modified as appropriate.

[0145] The structures of the main body shell 11 and the handle shell 15 can be changed appropriately. For example, the gear housing 12 and the motor housing 13 of the main body shell 11 can have shapes different from those in the embodiment, or can have connection methods different from those in the embodiment. The same applies to the handle shell 15. In addition, the elastic connection structure between the main body shell 11 and the handle shell 15 can also be changed appropriately. For example, the configuration of the elastic component 51 can also be changed. In addition, multiple elastic components can also be interposed between the main body shell 11 and the handle shell 15. In addition, in addition to the compression coil spring, the elastic component can also be made of various springs, rubbers, and synthetic resins.

[0146] The structure (shape, size, etc.), number, and arrangement position of the front guide portion 61 and the rear guide portion 62 can be modified as appropriate.

[0147] For example, in the above-described embodiment, the front guide portion 61 and the rear guide portion 62 have substantially the same structure. That is, the guide protrusion 611 and the guide protrusion 621 have substantially the same structure, and the recess 615 and the recess 625 have substantially the same structure. However, the front guide portion 61 and the rear guide portion 62 may have different structures as long as they are composed of a set of engaging portions that are each slidably engaged with each other. For example, the front guide portion 61 may be composed of a protrusion provided on the main body housing 11 and a recess (groove) provided on the handle housing 15, and the rear guide portion 62 may be composed of a recess (groove) provided on the main body housing 11 and a protrusion provided on the handle housing 15. A reverse combination may also be employed. Furthermore, the guide protrusions 611, 621 and the recesses 616, 626 may have shapes different from those in the above-described embodiment (e.g., a semicircular cross-section or a triangular cross-section).

[0148] Furthermore, in the above embodiment, a pair of front guides 61 and a pair of rear guides 62 are provided. However, only one front guide 61 and only one rear guide 62 may be provided. In this case, for example, a single guide protrusion 611 may be provided so as to protrude above the upper extension 141, with two corresponding recesses 616 provided on the upper wall of the cover 181. The rear guide 62 has a similar structure. Alternatively, only one of the front guide 61 and the rear guide 62 may be provided in the center of the left-right direction, while the other may be provided with a pair.

[0149] In addition, in the above-described embodiment, the front guide portion 61 and the rear guide portion 62 are arranged at approximately the same position in the vertical direction, but they can also be arranged at positions separated in the vertical direction. In addition, the distance between the front guide portion 61 and the rear guide portion 62 in the front-to-back direction can also be appropriately changed. However, in order to accurately guide the sliding of the main body housing 11 and the handle housing 15, it is preferable that the distance between the front guide portion 61 and the rear guide portion 62 is as large as possible. Therefore, it is preferable that the front guide portion 61 is provided at the front end portion of the handle housing 15, and the rear guide portion 62 is provided at the rear end portion of the main body housing 11.

[0150] The structure, number, and configuration position of the limiting portion 67 can be appropriately changed or omitted. For example, the limiting portion 67 can also be composed of an abutment portion 671 and a pair of protrusions made of resin, wherein the abutment portion 671 is provided on the main body shell 11, and the pair of protrusions made of resin are provided integrally with the left and right side walls of the handle shell 15 and can abut against the pair of abutment surfaces 672 of the abutment portion 671. Alternatively, the abutment plate 673 can be omitted so that the elastic component 677 can directly abut against the abutment surface 672. In addition, the elastic component 677 can also be other elastic components (such as springs or rubber) instead of synthetic resin foam.

[0151] In the above embodiment, the detection result of the relative position of the handle housing 15 relative to the main body housing 11 by the position detection mechanism 45 is used for no-load soft start control. However, other detection mechanisms that can detect the relative position of the handle housing 15 relative to the main body housing 11 can be used instead of the position detection mechanism 45. For example, a non-contact (for example, optical) sensor other than a magnetic field detection type can be used, or a contact detection mechanism (for example, a mechanical switch) can be used. In addition, the configuration of the position detection mechanism 45 can also be changed. In addition, the position detection mechanism 45 can also be omitted, and no-load soft start control can be performed.

[0152] The acceleration detection unit 43 can be located elsewhere within the base 18 (e.g., the lower extension 186). Furthermore, to detect the rotational state of the hammer drill 1 about the drive axis A1, a detector that detects other physical quantities (e.g., displacement, velocity, angular velocity, etc.) can also be employed. Such a detector is unnecessary in impact tools capable of only impacting, as excessive rotation does not occur. The elastic support structure of the acceleration sensor unit 43 can also be appropriately modified or omitted.

[0153] The hammer drill 1 may be configured to operate using power supplied from an external AC power source instead of the battery 93. That is, the battery mounting portion 187 may be omitted.

[0154] The configuration location of the controller 41 can be changed as appropriate. Furthermore, in the above embodiment, an example is given in which the control circuit of the controller 41 is composed of a microcomputer including a CPU, etc. However, other types of control circuits may be used. For example, programmable logic devices such as ASICs (Application Specific Integrated Circuits) and FPGAs (Field Programmable Gate Arrays) may be used. Furthermore, the control processing in the above embodiment may be distributed among multiple control circuits.

[0155] Furthermore, based on the gist of the present invention, the above-mentioned embodiment and its modifications, the following aspects 1 to 6 are constructed. At least one of the following aspects 1 to 6 can be employed in combination with any one of the above-mentioned embodiment and its modifications, and the inventions described in each claim.

[0156] [Mode 1] At least one of the first guide portion and the second guide portion is arranged as a pair symmetrically with respect to a plane including the first axis and the second axis.

[0157] [Mode 2] One of the first engaging portion and the second engaging portion includes at least one protrusion, and the other of the first engaging portion and the second engaging portion includes at least one recess that engages with the at least one protrusion.

[0158] [Mode 3] The at least one protrusion is in a rectangular parallelepiped shape, and the at least one recess is in a rectangular shape matching the at least one protrusion.

[0159] [Mode 4] The first contact portion has a pair of first contact surfaces, and the second contact portion has a pair of second contact surfaces.

[0160] [Mode 5] The one of the first abutting portion and the second abutting portion includes a pair of flexible plate members, and the pair of plate members are biased toward the other of the first abutting portion and the second abutting portion by elastic members.

[0161] [Mode 6] The grip portion has a first end and a second end, wherein the first end is arranged on the second axis, and the second end is an end on the side opposite to the first end and is located away from the second axis.

[0162] Furthermore, the following methods A to J are designed to provide an impact tool capable of appropriately detecting the pressure of the tool tip on the workpiece and controlling the drive of the motor. Methods A to J may be employed singly or in combination. Alternatively, at least one of Methods A to J may be employed in combination with the vibration tool 1 of the embodiment, the aforementioned variations, Methods A to J, and at least one of the inventions described in the respective technical solutions.

[0163] [Method A]

[0164] An impact tool comprising a motor, a drive mechanism, a main body shell, a handle shell, a movable part, a detector and a control device, wherein the motor comprises a stator, a rotor and a motor shaft, the motor shaft extending from the rotor and being rotatable around a first axis integrally with the rotor; the drive mechanism is configured to perform at least an impact action by the power of the motor, the impact action being an action of linearly driving a top tool along a second axis extending parallel to the first axis and defining the front-to-back direction of the impact tool; the main body shell accommodates the motor and the drive mechanism and extends in the front-to-back direction; the handle shell includes a handle for a user to hold The movable part is provided on one side of the main body shell and the handle shell, and is configured to move along with the relative movement of the other side of the main body shell and the handle shell in the front-to-back direction; the detector is provided on the side of the main body shell and the handle shell on which the movable part is provided, and is configured to detect the pressing of the top tool on the workpiece by detecting the movement of the movable part; the control device is configured to control the driving of the motor according to the detection result of the detector.

[0165] When the top tool is pressed against the workpiece, the handle shell elastically connected to the main body shell moves forward relative to the main body shell. That is, the transition from the no-load state to the loaded state corresponds to the relative movement of the handle shell forward. In the impact tool of this method, the relative movement of the other of the main body shell and the handle shell in the front-to-back direction corresponds to the movement of the movable part. Therefore, the detector can appropriately detect the pressing of the top tool on the workpiece (the transition from the no-load state to the loaded state) through the movement of the movable part. Moreover, the control device can control the drive of the motor according to whether the top tool is in the no-load state or the loaded state based on the detection result of the detector.

[0166] In addition, in the impact tool of this method, both the movable part and the detector are provided in one of the main body shell and the handle shell. In the case where the movable part is provided in the main body shell or the handle shell, and the detector and the movable part are provided independently of each other in the handle shell or the main body shell, due to the dimensional errors of the main body shell and the handle shell, the positional relationship between the movable part and the detector is different from the original setting, and it may not be possible to accurately detect the transition from the no-load state to the loaded state. In contrast, according to this method, by configuring both the movable part and the detector in the same part (main body shell or handle shell), the positional relationship between the movable part and the detector can be stabilized, thereby reducing the possibility of false detection.

[0167] [Method B]

[0168] The impact tool according to aspect A, wherein the handle case includes a cover portion that at least partially surrounds a portion of the main body case in a circumferential direction around the second axis, and both the movable member and the detector are installed inside the cover portion and an outer peripheral portion of the portion of the main body case.

[0169] In the impact tool of this aspect, both the movable member and the detector can also be installed inside the cover portion, and both the movable member and the detector can also be installed in the outer peripheral portion of the portion of the main body case. According to this aspect, the movable member and the detector can be arranged without increasing the impact tool in the front-rear direction.

[0170] [Aspect C]

[0171] The impact tool according to aspect A or B, further comprising first and second guide portions configured to guide relative sliding of the main body case and the handle case in the front-rear direction, the first and second guide portions being arranged apart from each other in the front-rear direction, and the movable member and the detector being arranged between the first and second guide portions in the front-rear direction.

[0172] According to this aspect, since the movable member and the detector are arranged at a position at which the main body case and the handle case are stably relatively moved in the front-rear direction, detection accuracy can be improved.

[0173] [Aspect D]

[0174] The impact tool according to any one of aspects A to C, wherein the movable member is configured to be movable in a straight line, and the detector is configured to detect straight-line movement of the movable member.

[0175] According to this aspect, a simple and small detection mechanism can be realized.

[0176] [Aspect E]

[0177] The impact tool according to aspect D, wherein the other of the main body case and the handle case has an abutting portion configured to abut against the movable member in conjunction with relative movement and move the movable member in the front or rear direction, and the impact tool further comprises a force applying member configured to apply a force to the movable member toward the abutting portion, the abutting portion, the movable member, and the force applying member being arranged on a straight line extending in the front-rear direction.

[0178] According to this aspect, the movable member can be moved in a straight line with high precision.

[0179] [Mode F]

[0180] The impact tool according to Mode E, wherein the detection object of the detector is provided on the movable member at a position deviated from the straight line.

[0181] According to the present mode, the degree of freedom of the configuration position of the detector and the support structure of the movable member can be improved.

[0182] [Mode G]

[0183] The impact tool according to any one of Modes D to F, wherein the detection object of the detector is a magnet mounted on the movable member, and the movable member is formed of synthetic resin.

[0184] According to the present mode, the possibility of false detection of the detector can be reduced.

[0185] [Mode H]

[0186] The impact tool according to Mode G, wherein the one of the main body case and the handle case has a recess for the movable member to be configured so as to be slidable in the front-rear direction, and the impact tool further has a restriction member made of aluminum configured to restrict the movable member from moving in a direction away from the recess.

[0187] According to the present mode, the assembly of the movable member can be facilitated and a reasonable structure for holding the movable member without affecting the magnet can be realized.

[0188] [Mode I]

[0189] The impact tool according to any one of Modes A to H, wherein both the movable member and the detector are mounted on the handle case.

[0190] According to the present mode, the detector as a precision device can be effectively protected from vibration.

[0191] [Mode J]

[0192] The impact tool according to any one of Modes A to I, wherein the grip portion extends in a direction intersecting the second axis at the rear of the main body case, and has a first end portion and a second end portion, wherein the first end portion is configured on the second axis, and the second end portion is an end portion on the side opposite to the first end portion, at a position away from the second axis,

[0193] The handle case includes a connection portion that connects the second end portion of the grip portion and the main body case in a manner of forming a ring portion together with the grip portion.

[0194] The following shows the correspondence relationship between each of the components of the above-described embodiment and each of the components of Modes A to J. However, each of the components of the embodiment is only an example, and does not limit each of the components of the invention.

[0195] The hammer drill 1 is an example of an "impact tool". The motor 2, the stator 21, the rotor 23, the motor shaft 25, and the rotation axis A2 are examples of a "motor", a "stator", a "rotor", a "motor shaft", and a "first axis", respectively. The drive mechanism 3 and the drive axis Al are examples of a "drive mechanism" and a "second axis", respectively. The tip tool 91 is an example of a "tip tool". The main body case 11 is an example of a "main body case". The handle case 15 and the grip portion 17 are examples of a "handle case" and a "grip portion", respectively. The movable member 451 is an example of a "movable member". The Hall sensor 458 is an example of a "detector". The controller 41 (control circuit) is an example of a "control device".

[0196] The cover portion 181 is an example of a "cover portion". The front side guide portion 61 and the rear side guide portion 62 are examples of a "first guide portion" and a "second guide portion", respectively. The force applying member 457 is an example of a "force applying member". The pressing protrusion 65 is an example of an "abutting portion". The magnet 456 is an example of a "magnet". The guide recess 463 is an example of a "recess". The cover plate 467 is an example of a limiting member. The grip portion 17 is an example of a "grip portion". The upper end portion and the lower end portion of the grip portion 17 are examples of a "first end portion" and a "second end portion", respectively. The base portion 18 is an example of a "connection portion".

[0197] Further, the electric power tools described in Modes A to J are not limited to the hammer drill 1 exemplified in the above-described embodiment. For example, the following exemplified modifications can be made. Further, at least one of these modifications can be adopted in combination with at least one of the invention described in the hammer drill 1 of the embodiment, the above-described modified example, the modes, and each of the technical solutions.

[0198] In the above-described embodiment, as the impact tool, the hammer drill 1 is exemplified, but the invention can also be applied to impact tools other than the hammer drill 1 (for example, an electric hammer). In addition, the hammer drill 1 can have only two operation modes of an electric hammer mode and a drilling mode. According to the impact tool to which the invention is applied, the motor 2 and the drive mechanism 3 can be appropriately changed.

[0199] The structures of the main housing 11 and the handle housing 15 can be modified as appropriate. For example, the gear housing 12 and the motor housing 13 of the main housing 11 can each have a shape different from that of the embodiment, or can each have a connection method different from that of the embodiment. In addition, for example, instead of the handle housing 15, a handle housing having the following structure can be used, namely, a cylindrical cover portion that circumferentially surrounds the rear end portion of the main housing 11 and a (cantilevered) grip portion that protrudes from the cover portion in a direction intersecting the drive axis A1.

[0200] The elastic connection structure between the main body housing 11 and the handle housing 15 can also be modified as appropriate. For example, the configuration of the elastic member 51 can be modified. Alternatively, multiple elastic members can be interposed between the main body housing 11 and the handle housing 15. Furthermore, in addition to compression coil springs, the elastic member can also be made of various springs, rubber, or synthetic resin.

[0201] Furthermore, the structure, number, arrangement position, etc. of the front guide portion 61 , the rear guide portion 62 , and the restriction portion 67 may be appropriately changed or omitted.

[0202] In addition, the structure and arrangement position of the position detection mechanism 45 for detecting the pressing of the tip tool 91 against the workpiece are not limited to the examples in the above-described embodiment.

[0203] For example, the movable part 451 may not be T-shaped, but may be in other shapes such as an arc or a cylinder. Similarly, the shape of the pressing protrusion 65 that contacts the movable part 451 may also be changed appropriately. In addition, the movable part 451 may not be supported to move in a straight line, but may be supported to move in an arc shape, for example. The support method of the movable part 451 may also be changed corresponding to the change or independently of the change. Depending on the support method, the cover plate 467 may be omitted. The magnet 456, the pressing protrusion 65, the movable part 451, and the force-applying part 457 may also be in the same straight line. In this case, the configuration position of the Hall sensor 458 may also be changed appropriately. In addition to the compression coil spring, the force-applying part 457 may also be made of various springs, rubbers, and synthetic resins, and its configuration position may also be changed appropriately.

[0204] For example, the movable member 451 and the Hall sensor 458 may be mounted on the right side, upper wall, or lower wall instead of the left side wall of the cover 181. Alternatively, both the movable member 451 and the Hall sensor 458 may be mounted on the main body housing 11 (e.g., the upper extension 141). In this case, for example, the protrusion provided inside the handle housing 15 only needs to move the movable member 451 as the handle housing 15 moves relative to the handle housing 15.

[0205] In addition, the manner of detecting the operation of the movable member 451 is not particularly limited, and an optical sensor can be used, or a mechanical switch of a contact type can be used instead of the magnetic field detection type Hall sensor 458. Furthermore, the detector needs to be installed in the same one of the main body case 11 and the handle case 15 as the movable member 451, but the position thereof can be appropriately set according to the structure of the movable member 451 and the detection manner.

[0206] The acceleration detection unit 43 can be arranged at other positions (for example, the lower side extension 186) in the base 18. In addition, in order to detect the rotation state of the hammer drill 1 rotating around the driving axis Al, a detector that detects other physical quantities (for example, displacement, speed, angular velocity, and the like) can also be used. In an impact tool that can only perform an impact operation, since excessive rotation does not occur, such a detector is not needed. The elastic support structure of the acceleration sensor unit 43 can also be appropriately changed or omitted.

[0207] The hammer drill 1 can also be configured to operate using power supplied from an external alternating current power supply instead of the battery 93. That is, the battery mounting portion 187 can be omitted.

[0208] The arrangement position of the controller 41 can be appropriately changed. In addition, in the above-described embodiment, an example in which the control circuit of the controller 41 is configured by a microcomputer including a CPU or the like is exemplified, but other kinds of control circuits can also be used. For example, a programmable logic device such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array) can be used. In addition, the control processing of the above-described embodiment can also be processed by a plurality of control circuits in a distributed manner.

Claims

1. An impact tool, characterized in that: It has a motor, a driving mechanism, a main body shell, a handle shell, a first guide part and a second guide part, wherein, The motor includes a stator, a rotor, and a motor shaft extending from the rotor and rotatable integrally with the rotor about a first axis. The driving mechanism is configured to be capable of performing at least an impact action by the power of the motor, wherein the impact action is an action of linearly driving the tip tool along a second axis extending parallel to the first axis and defining the front-rear direction of the impact tool. The main body housing accommodates the motor and the drive mechanism. The handle housing is formed into a ring shape and includes an elongated grip portion that extends behind the main body housing in a direction intersecting the second axis. The handle housing is connected to the main body housing via a first elastic component in a manner that allows it to move relative to the main body housing at least in the front-rear direction. The first guide portion and the second guide portion are configured to guide relative sliding movement of the main body housing and the handle housing in the front-rear direction. The first guide portion and the second guide portion respectively include a first engaging portion and a second engaging portion, wherein the first engaging portion is provided on the main body housing, and the second engaging portion is provided on the handle housing and engages with the first engaging portion in a manner capable of sliding along the front-rear direction. The second guide portion is separated from the first guide portion and is arranged at a position behind the first guide portion. A direction perpendicular to the second axis and corresponding to the extending direction of the grip portion defines the vertical direction of the impact tool. The main body housing includes a stator housing portion and a first extension portion, wherein the stator housing portion houses the stator, and the first extension portion is located above the first axis and extends rearward relative to the stator housing portion. The handle housing includes a cover portion and a second extension portion, wherein the cover portion at least partially surrounds the stator accommodating portion in a circumferential direction around the first axis, and the second extension portion extends forward from the upper end portion of the grip portion and is connected to the cover portion, and covers at least a portion of the first extension portion. The first engaging portion of the second guide portion is provided at a portion of the first extending portion that protrudes into the second extending portion. The second engaging portion of the second guide portion is disposed in the second extending portion.

2. The impact tool according to claim 1, wherein At least one of the first guide portion and the second guide portion is arranged behind a rear end of the stator of the motor.

3. The impact tool according to claim 1, wherein The first guide portion is arranged radially outside the stator.

4. The impact tool according to claim 1, wherein At least one of the first engaging portion and the second engaging portion includes a metal portion that slides with the other of the first engaging portion and the second engaging portion.

5. The impact tool according to claim 1, wherein It has a movable part, a detector and a control device, wherein, The movable member is provided in one of the main body housing and the handle housing and is configured to move along with the relative movement of the other of the main body housing and the handle housing in the front-rear direction. The detector is provided on the one of the main body housing and the handle housing where the movable member is provided, and is configured to detect the pressing of the top tool on the workpiece by detecting the movement of the movable member. The control device is configured to control the driving of the motor according to the detection result of the detector. The movable member and the detector are arranged between the first guide portion and the second guide portion in the front-rear direction.

6. An impact tool, characterized in that: It has a motor, a driving mechanism, a main body shell, a handle shell, a first guide part and a second guide part, wherein, The motor includes a stator, a rotor, and a motor shaft extending from the rotor and rotatable integrally with the rotor about a first axis. The driving mechanism is configured to be capable of performing at least an impact action by the power of the motor, wherein the impact action is an action of linearly driving the tip tool along a second axis extending parallel to the first axis and defining the front-rear direction of the impact tool. The main body housing accommodates the motor and the drive mechanism. The handle housing is formed into a ring shape and includes an elongated grip portion that extends behind the main body housing in a direction intersecting the second axis. The handle housing is connected to the main body housing via a first elastic component in a manner that allows it to move relative to the main body housing at least in the front-rear direction. The first guide portion and the second guide portion are configured to guide relative sliding movement of the main body housing and the handle housing in the front-rear direction. The first guide portion and the second guide portion respectively include a first engaging portion and a second engaging portion, wherein the first engaging portion is provided on the main body housing, and the second engaging portion is provided on the handle housing and engages with the first engaging portion in a manner capable of sliding along the front-rear direction. The second guide portion is separated from the first guide portion and is arranged at a position behind the first guide portion. A direction perpendicular to the second axis and corresponding to the extending direction of the grip portion defines the vertical direction of the impact tool. The direction perpendicular to the front-back direction and the up-down direction defines the left-right direction of the impact tool. The impact tool further includes a restriction portion configured to restrict relative movement of the main body housing and the handle housing in the left-right direction. The limiting portion includes a first abutting portion and a second abutting portion, the first abutting portion and the second abutting portion being respectively provided on the main body housing and the handle housing and capable of abutting against each other. The first guide portion and the second guide portion are arranged above the first axis. The restriction portion is arranged below the first axis.

7. The impact tool according to claim 6, wherein: At least one of the first guide portion and the second guide portion is arranged behind a rear end of the stator of the motor.

8. The impact tool according to claim 6, wherein The first guide portion is arranged radially outside the stator.

9. The impact tool according to claim 6, wherein One of the first and second abutting portions is urged toward the other of the first and second abutting portions and slidably contacts the other.

10. The impact tool according to claim 6, wherein The restriction portion is arranged between the first guide portion and the second guide portion in the front-rear direction.

11. The impact tool according to claim 6, wherein A direction perpendicular to the second axis and corresponding to the extending direction of the grip portion defines the vertical direction of the impact tool. The main body housing includes a stator housing portion and a third extension portion, wherein the stator housing portion houses the stator, and the third extension portion extends rearward relative to the stator housing portion at a position below the first axis and protrudes into the handle housing. The third extending portion includes the first contact portion and is configured to guide the electric wire extending from the motor.

12. The impact tool according to claim 6, wherein The first abutting portion and the second abutting portion of the restricting portion are in contact with each other in a slidable manner. The first elastic member is arranged below the first guide portion and the second guide portion in the up-down direction and above the restriction portion.

13. The impact tool according to claim 6, wherein At least one of the first engaging portion and the second engaging portion includes a metal portion that slides with the other of the first engaging portion and the second engaging portion.

14. The impact tool according to claim 6, wherein It has a movable part, a detector and a control device, wherein, The movable member is provided in one of the main body housing and the handle housing and is configured to move along with the relative movement of the other of the main body housing and the handle housing in the front-rear direction. The detector is provided on the one of the main body housing and the handle housing where the movable member is provided, and is configured to detect the pressing of the top tool on the workpiece by detecting the movement of the movable member. The control device is configured to control the driving of the motor according to the detection result of the detector. The movable member and the detector are arranged between the first guide portion and the second guide portion in the front-rear direction.

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