Power tool

Abstract

The present invention provides a power tool. A hammer drill (1A) has a motor (2), a housing (10), a battery holder (5A), and a buffer member (6A). The housing (10) is for accommodating the motor (2). The battery holder (5A) is configured to detachably hold a battery (8) for supplying electric power to the motor (2). The battery holder (5A) is held by the housing (10) in a state capable of moving relative to the housing (10). The buffer member (6A) is held by the housing (10). The buffer member (6A) is arranged so as to cross the moving direction of the battery holder (5A), and is interposed between the battery (8) and the housing (10) when the battery (8) is mounted on the battery holder (5A). According to the present invention, a technique for protecting a battery in a power tool configured to detachably hold a battery can be provided.

Description

Technical Field

[0001] The present invention relates to a power tool configured with a detachable battery. Background Art

[0002] Various power tools powered by rechargeable batteries are known. For example, in Patent Document 1, a hammer drill having a housing with a detachable battery is disclosed. When the upper end portion of the battery is mounted on the battery mounting portion, the lower end portion of the battery protrudes from the housing to the outside.

[0003] [Prior Art Documents]

[0004] [Patent Documents]

[0005] Patent Document 1: Japanese Patent Application Laid-Open Publication No. 2018-79557 Summary of the Invention

[0006] [Technical Problem to be Solved by the Invention]

[0007] In the above-mentioned hammer drill, battery protection portions that protrude more downward than the battery protection portion are provided on the front side and the rear side of the battery mounting portion. These battery protection portions can effectively protect the battery from external forces. On the other hand, it is sometimes difficult to arrange such battery protection portions.

[0008] The technical problem to be solved by the present invention is to provide a technique that helps protect the battery in a power tool configured with a detachable battery.

[0009] [Technical Solution for Solving the Technical Problem]

[0010] According to one technical solution of the present invention, there is provided a power tool having a motor, a housing, a battery holder, and a buffer member. The housing is for housing the motor. The battery holder is configured to be detachable for supplying electric power to the motor. In addition, the battery holder is held by the housing in a state where it can move relative to the housing. The buffer member is held by the housing so as to cross the moving direction of the battery holder. In addition, the buffer member is directly or indirectly interposed between the battery and the housing when the battery is mounted on the battery holder.

[0011] According to this technical solution, for example, when the power tool falls and an external force is applied to the battery, the battery holder moves relative to the housing, thereby avoiding an impact on the battery. In addition, the buffer member can absorb the impact. Thus, according to this technical solution, a power tool that can effectively protect the battery from external forces is realized.

[0012] In a technical solution of the present invention, the power tool may further include a biasing member that biases the battery holder in a direction away from the buffer member in the moving direction of the battery holder. According to this technical solution, the buffering effect of the buffer member when the battery holder moves can be improved. Also, in this technical solution, the battery holder can be held in the initial position by the biasing force of the biasing member when no external force is applied in the direction approaching the buffer member. Moreover, the buffer member may be configured to be separated from the battery mounted on the battery holder when the battery holder is in the initial position, and to abut against the battery as the battery holder moves from the initial position. In this case, the buffering effect of the buffer member can be further improved.

[0013] In a technical solution of the present invention, the buffer member may also be configured to be able to abut against the battery at multiple locations. According to this technical solution, the buffer member is easily deformed, thereby improving the buffering effect of the buffer member.

[0014] In a technical solution of the present invention, the buffer member may also be disposed on the advancing direction side of the battery when the battery is mounted on the battery holder. According to this technical solution, a reasonable configuration of the buffer member that does not interfere with the installation of the battery is achieved.

[0015] In a technical solution of the present invention, the housing and the battery holder may also be engaged with each other in a slidable state. According to this technical solution, when an external force is applied to the battery, the battery holder can easily move relative to the housing.

[0016] In a technical solution of the present invention, the battery holder may also be able to move relative to the housing in multiple directions. According to this technical solution, the battery can be more effectively protected from external forces from various directions.

[0017] In a technical solution of the present invention, the battery holder may further include a first terminal that can be electrically connected to the second terminal of the battery, a terminal block for supporting the first terminal, a first member, and a second member. The first member and the second member may also clamp the terminal block and hold it. According to this technical solution, a battery holder with excellent assemblability is achieved.

[0018] In one technical solution of the present invention, the battery may further have a case and a locking member. The locking member may be movable between a first position protruding from the case and a second position protruding less from the case than the first position. In addition, the meaning of "protruding less from the case than the first position" as mentioned herein also includes the case where the locking member slightly protrudes from the case and the case where it does not protrude from the case. The battery holder may further have an engaging portion that can engage with the locking member disposed at the first position. According to this technical solution, even when the battery holder moves relative to the housing, the engagement of the locking member can be stably maintained, and further, the mounting state of the battery relative to the battery holder can be stably maintained.

[0019] In addition, in this technical solution, the housing may further have an abutting portion configured to abut against the locking member during the process of mounting the battery on the battery mounting portion, causing the locking member to move from the first position to the second position. In this case, compared with the case where the abutting portion is provided on the battery holder that moves relative to the housing together with the battery, it is easier to move the locking member.

[0020] In one technical solution of the present invention, the power tool may further be an impact tool configured to linearly drive a tip tool along a drive axis by the power of a motor. When a battery is mounted on the battery holder, a part of the battery may form a part of the outer contour of the impact tool. Since impact tools tend to be heavier than other types of power tools, there is a great demand for protecting the battery. According to this technical solution, the battery of the impact tool can be effectively protected by the battery holder and the buffer member. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a cross-sectional view of a hammer drill.

[0022] Figure 2 is Figure 1 a partial enlarged view of

[0023] Figure 3 is Figure 2 a cross-sectional view taken along line III-III of

[0024] Figure 4 is an exploded perspective view of the battery holder.

[0025] Figure 5 is Figure 2 a cross-sectional view taken along line V-V of

[0026] Figure 6 is an explanatory view showing the state when the battery holder moves.

[0027] Figure 7 is a partially cut-away view of the hammer drill.

[0028] Figure 8 is Figure 7 a cross-sectional view taken along line VIII-VIII.

[0029] [Description of Reference Numerals]

[0030] 1A, 1B: Hammer drill; 10: Housing; 11: First housing; 111: Drive mechanism receiving portion; 117: Motor receiving portion; 121: Elastic member; 123: Elastic member; 13: Second housing; 131: Gripping portion; 133: Upper side portion; 135: Lower side portion; 136: Connecting portion; 137: Opening; 138: Controller receiving portion; 139: Recess; 14A, 14B: Holding portion; 141: Side wall; 142: Guide groove; 143: Stopper; 145: Rear wall; 146: Contact portion; 148: Recess; 151: Controller; 153: Trigger; 154: Switch; 2: Motor; 25: Motor shaft; 3: Drive mechanism; 30: Motion conversion mechanism; 34: Tool holder; 36: Impact structure element; 38: Rotation transmission mechanism; 39: Mode changeover dial; 5A, 5B: Battery holder; 51: Case; 511: Left side member; 512: Right side member; 514: Opening; 515: Opening; 517: Projection; 52: Guide rail; 53: Guide rail; 54: Projection; 55: Terminal; 56: Terminal block; 58: Biasing member; 59: Hook engaging member; 591: Engaging portion; 6A, 6B: Buffer member; 61: Groove; 8: Battery; 81: Case; 83: Guide groove; 85: Hook; 87: Button; A1: Drive axis. Detailed Description of the Invention

[0031] Hereinafter, embodiments will be described with reference to the drawings. In addition, in the following embodiments, a hammer drill is illustrated as an example of a power tool. The hammer drill is also an example of an impact tool configured to linearly drive a tip tool.

[0032] First, with reference to Figures 1 to 6 , a hammer drill 1A according to an embodiment will be described. The hammer drill 1A is configured to perform an operation (hammering operation) of linearly driving a tip tool (not shown) along the drive axis A1 and an operation (drilling operation) of rotationally driving the tip tool around the drive axis A1 using the battery 8 as a power source.

[0033] First, with reference to Figure 1 the schematic structure of the hammer drill 1A will be described. As shown in Figure 1 , the outer contour of the hammer drill 1A is mainly formed by the housing 10. The housing 10 of the present embodiment is configured as a so-called vibration-proof housing and includes a first housing 11 and a second housing 13 elastically connected to the first housing 11.

[0034] The first housing 11 is integrally formed in a substantially L shape. The first housing 11 includes: a motor housing portion 117 for housing the motor 2; and a drive mechanism housing portion 111 for housing the drive mechanism 3, the drive mechanism 3 being configured to drive the tip tool by the power of the motor 2.

[0035] The drive mechanism housing portion 111 is formed in a long shape and extends along the drive axis A1. A tool holder 34 for detachably attaching the tip tool is disposed at one end portion of the drive mechanism housing portion 111 in the long axis direction. The motor housing portion 117 is connected and fixed to the other end portion of the drive mechanism housing portion 111 in the long axis direction. The motor housing portion 117 intersects (specifically, is substantially orthogonal to) the drive axis A1 and protrudes from the drive mechanism housing portion 111 in a direction away from the drive axis A1. The motor 2 is disposed such that the rotation axis of the motor shaft 25 is orthogonal to the drive axis A1.

[0036] In addition, in the following description, for convenience, the extending direction of the drive axis A1 of the hammer drill 1A (the long axis direction of the drive mechanism housing portion 111) is defined as the front-rear direction of the hammer drill 1A. In the front-rear direction, the end portion side where the tool holder 34 is disposed is defined as the front side of the hammer drill 1A, and the opposite side of the end portion where the tool holder 34 is disposed is defined as the rear side. Further, the extending direction of the rotation axis of the motor shaft 25 is defined as the up-down direction of the hammer drill 1A. In the up-down direction, the direction in which the motor housing portion 117 protrudes from the drive mechanism housing portion 111 is defined as the lower side, and the opposite direction of the direction in which the motor housing portion 117 protrudes from the drive mechanism housing portion 111 is defined as the upper side. And the direction orthogonal to the front-rear direction and the up-down direction is defined as the left-right direction.

[0037] The second housing 13 is an integrally formed substantially U-shaped hollow body, which includes a grip portion 131, an upper side portion 133, and a lower side member 135.

[0038] The gripping portion 13 is a portion configured to be gripped by the user. The gripping portion 131 extends rearward away from the first housing 11 and extends in the vertical direction. A trigger 153 for the user to perform a pressing operation (triggering operation) with a finger is provided at the front portion of the gripping portion 131. The upper side portion 133 is a portion connected to the upper end portion of the gripping portion 131. In the present embodiment, the upper side portion 133 is configured to extend forward from the upper end portion of the gripping portion 131 and cover most of the drive mechanism housing portion 111 of the first housing 11. The lower side portion 135 is a portion connected to the lower end portion of the gripping portion 131. In the present embodiment, the lower side portion 135 extends forward from the lower end portion of the gripping portion 131, and the front side portion thereof is disposed below the motor housing portion 117. A battery holder 5A is held at the lower end portion of the rear end portion of the lower side portion 135. The hammer drill 1A operates using a battery 8 detachably attached to the battery holder 5A as a power source.

[0039] With the above structure, in the hammer drill 1A, in addition to the second housing 13, the motor housing portion 117 in the first housing 11 is exposed to the outside in a state of being sandwiched from above and below by the upper side portion 133 and the lower side portion 135. The second housing 13 and the motor housing portion 117 form the outer surface of the hammer drill 1A. Further, in the present embodiment, the second housing 13 is formed of a left housing and a right housing. More specifically, the left housing and the right housing made of synthetic resin are respectively connected to each other by screws in a state of sandwiching the first housing 11 from the left and the right, thereby forming the housing 10.

[0040] Next, the detailed structure of the hammer drill 1A will be described.

[0041] First, with reference to Figure 1 , the vibration-proof structure of the housing 10 will be briefly described. As described above, in the housing 10, the second housing 13 including the gripping portion 131 is elastically connected to the first housing 11 so as to be relatively movable with respect to the first housing 11, and the first housing 11 houses the motor 2 and the drive mechanism 3.

[0042] More specifically, as Figure 1As shown, the elastic member 121 is interposed between the drive mechanism housing portion 111 of the first housing 11 and the upper side portion 133 of the second housing 13. And the elastic member 123 is interposed between the motor housing portion 117 of the first housing 11 and the lower side portion 135 of the second housing 13. In addition, in the present embodiment, a compression coil spring is adopted as the elastic member 121 and the elastic member 123. The elastic member 121 and the elastic member 123 respectively apply forces to the first housing 11 and the second housing 13 in the directions away from each other in the extending direction of the drive axis A1 (the direction in which the holding portion 131 is away from the first housing 11). That is, the first housing 11 and the second housing 13 are respectively applied forces forward and backward. In addition, although detailed illustrations and descriptions are omitted, a guiding structure is provided on the first housing 11 and the second housing 13 for guiding the relative movement of the first housing 11 and the second housing 13 in the front-rear direction.

[0043] According to the anti-vibration structure described above, the first housing 11 and the second housing 13 can move relative to each other in the front-rear direction. Therefore, it is possible to effectively suppress the following vibration from being transmitted to the second housing 13, which is the vibration generated in the first housing 11 during the hammering action and is the largest and dominant vibration in the extending direction (front-rear direction) of the drive axis A1.

[0044] Hereinafter, the internal structure of the first housing 11 will be described.

[0045] As Figure 1 shown, a motor 2 is housed in the motor housing portion 117. In the present embodiment, a brushless DC motor is adopted as the motor 2. The upper and lower end portions of the motor shaft 25 are rotatably supported by bearings. The upper end portion of the motor shaft 25 projects into the drive mechanism housing portion 111, and a drive gear is formed at this portion.

[0046] A drive mechanism 3 is housed in the drive mechanism housing portion 111. The drive mechanism 3 has a motion conversion mechanism 30, an impact structure element 36, and a rotation transmission mechanism 38. In addition, since the drive mechanism 3 having such a structure is well-known, it will be simply described below.

[0047] The motion conversion mechanism 30 is configured to convert the rotational motion of the motor shaft 25 into linear motion and transmit it to the impact structural element 36. In the present embodiment, a crank mechanism including a crank shaft and a piston is adopted as the motion conversion mechanism 30. When the driving motor 2 is driven and the piston moves forward, under the action of the air spring, the impact structural element 36 transmits kinetic energy to the tip tool. Accordingly, the tip tool is linearly driven along the driving axis A1, thereby impacting the workpiece. On the other hand, when the piston moves backward, the impact structural element 36 and the tip tool return to their original positions. In this way, the hammering action is performed by the motion conversion mechanism 30 and the impact structural element 36.

[0048] The rotational transmission mechanism 38 is configured to transmit the rotational power of the motor shaft 25 to the tool holder 34. In the present embodiment, the rotational transmission mechanism 38 is configured as a gear reduction mechanism including a plurality of gears. An engaging clutch is arranged on the power transmission path of the rotational transmission mechanism 38. When the clutch is in the engaged state, the tool holder 34 is rotated by the rotational transmission mechanism 38, thereby driving the tip tool mounted on the tool holder 34 to rotate around the driving axis A1. On the other hand, when the engagement state of the clutch is released, the power transmission to the tool holder 34 based on the rotational transmission mechanism 38 is cut off, and thus the tip tool cannot be driven to rotate.

[0049] In the present embodiment, the hammer drill 1A is configured to operate in response to one of the two modes selected from the hammering mode and the hammer drill mode. The hammering mode is a mode in which only the motion conversion mechanism 30 is driven by releasing the engagement state of the clutch, thereby performing only the hammering action. The hammer drill mode is a mode in which the motion conversion mechanism 30 and the rotational transmission mechanism 38 are driven by engaging the clutch, thereby performing the hammering action and the drilling action. The mode of the hammer drill 1A is switched by a clutch switching mechanism that operates in response to the rotational operation of a mode switching dial 39 provided on the first housing 11. In addition, since the switching of the mode is a well-known technique, the detailed description and illustration thereof are omitted here.

[0050] Hereinafter, the second housing 13 and its internal structure will be described.

[0051] As Figure 1 shown, the upper side portion 133 is connected to the upper end portion of the grip portion 131 and extends forward. The rear side portion of the upper side portion 133 is formed in a substantially rectangular box shape with an open bottom and covers the rear side portion of the drive mechanism housing portion 111 from above. In addition, the front side portion of the upper side portion 133 is formed in a cylindrical shape and covers the outer periphery of the front side portion of the drive mechanism housing portion 111 (more specifically, the portion accommodating the tool holder 34).

[0052] The holding part 131 is configured as a cylindrical part extending in the vertical direction. As described above, a trigger 153 is provided at the front part of the holding part 131. The trigger 153 is held so as to be rotatable in a substantially front-rear direction with the lower end as a fulcrum. A switch 154 is disposed inside the holding part 131. The switch 154 remains in an off state in the initial state where the trigger 153 is not pressed, and on the other main surface, when the trigger 153 is pressed, it switches to an on state. The switch 154 is configured to be electrically connected to the controller 151 through a wiring (not shown) and output a signal indicating the on state or the off state to the controller 151.

[0053] As Figure 1 shown, the lower side part 135 is configured as a hollow body connected to the lower end part of the holding part 131 and extending forward. The rear side part of the lower side part 135 is formed to have a height in the vertical direction smaller than that of the front side part. Hereinafter, this part will be referred to as the connecting part 136. A battery holder 5A for detachably holding the battery 8 is held at the lower end part of the connecting part 136. The battery holder 5A and its holding structure will be described in detail later.

[0054] The front side part of the lower side part 135 is formed in a substantially rectangular box shape and protrudes more downward than the connecting part 136. The controller 151 is housed inside the rear end part of this part. Hereinafter, the front side part of the lower side part 135 will be referred to as the controller housing part 138. The controller 151 is configured to drive the motor 2 during the period when the switch 154 is in the on state according to the signal from the switch 154. When the battery 8 is mounted on the battery holder 5A, the controller housing part 138 is located on the front side of the battery 8. In addition, the lower surface of the controller housing part 138 is arranged at a position substantially the same as the lower surface of the battery 8 in the vertical direction. A buffer member 6A is held at the rear side of the controller housing part 138. The buffer member 6A will be described in detail later.

[0055] Next, the details of the battery holder 5A and its peripheral parts will be described.

[0056] First, the structure of the battery 8 that can be mounted on the battery holder 5A will be described. The battery 8 is a rechargeable battery (also referred to as a battery pack: battery pack) having a well-known structure, and has a case 81 and a plurality of battery cells (not shown) housed in the case 81. As Figure 2 and Figure 3As shown, the box body 81 is formed in a substantially rectangular parallelepiped shape. A pair of guide grooves 83, hooks 85, buttons 87, and terminals (specifically, a positive output terminal and a negative output terminal, both of which are omitted from the illustration) are provided on the box body 81. In addition, in the following description, for convenience, regarding the direction of the battery 8, in the state where it is installed in the hammer drill 1A, its up-and-down direction is defined.

[0057] A pair of guide grooves 83 are provided on a pair of side walls of the box body 81 along the length direction of the battery 8 (the direction orthogonal to the left-right direction of Figure 2 and the paper surface direction of Figure 3 ). Each guide groove 83 is a groove formed on the outer surface side of the upper end portion of the side wall and extending linearly in the length direction.

[0058] The hook 85 is provided at one end portion of the box body 81 in the length direction. The hook 85 is always biased upward and is held in a protruding position protruding from the upper surface of the box body 81 (the position shown in Figure 2 ) in the state where no downward external force is applied. The hook 85 is configured to move to a retracted position lower than the protruding position (in this embodiment, a position lower than the upper surface of the box body 81) when the button 87 provided near the hook 85 is pressed. In addition, the hook 85 has a rear end surface and an inclined surface, wherein the rear end surface is substantially orthogonal to a straight line extending in the front-rear direction; the inclined surface slopes downward as it approaches the front from the upper end of the rear end surface. The terminals are provided at the upper end portion of the box body 81.

[0059] Next, the structure of the battery holder 5A will be described. The battery holder 5A is a component configured to detachably hold the battery 8 and is held by the housing 10 in a state where it can move in the front-rear direction relative to the housing 10. As Figure 2 Figure 4 shown, in this embodiment, the battery holder 5A mainly includes a terminal 55, a terminal block 56, and a box body 51.

[0060] The terminal 55 is a terminal that can be electrically connected to the terminals of the battery 8. Although detailed illustrations are omitted, the terminal 55 at least includes a positive input terminal and a negative input terminal that can be respectively connected to the positive output terminal and the negative output terminal of the battery 8. The terminal 55 is supported by the terminal block 56. The terminal block 56 is a component that is rectangular when viewed from above.

[0061] The box body 51 is configured to hold the terminal block 56 and to removably accommodate the battery 8.

[0062] In this embodiment, the housing 51 is an overall hollow body in a substantially rectangular parallelepiped shape, formed by connecting and fixing two members (hereinafter also referred to as the left member 511 and the right member 512) divided in the left-right direction to each other using screws. In addition, the left member 511 and the right member 512 are made of synthetic resin. The left member 511 and the right member 512 respectively sandwich the terminal block 56 from the left and the right, and hold the terminal block 56 in a manner that it cannot move relative to the housing 51. With the structure of sandwiching the housing 51 by these two members, the assemblability can be improved.

[0063] An opening 514 is provided in the upper wall of the housing 51, and this opening 514 is used to pull out an electric wire (not shown) connected to the terminal block 56. In addition, this electric wire passes through an opening 137 provided in the bottom wall of the connecting portion 136 and is connected to the controller 151.

[0064] An opening 515 is formed in the lower wall of the housing 51. The opening 515 is an opening for housing the upper end portion of the battery 8. The rear end of the opening 515 is open, so that the upper end portion of the battery 8 can enter the housing 51 from the rear end of the opening 515 toward the front. A pair of guide rails 52 are provided at the lower end portion of the housing 51. The guide rails 52 are respectively provided at the lower end portions (the portions above the opening 515) of a pair of left and right side walls of the housing 51, and extend in the front-rear direction in parallel with each other. The pair of guide rails 52 can slidably engage with a pair of guide grooves 83 provided at the upper end portion of the battery 8. When installing the battery 8 into the housing 51, the battery 8 slides linearly from the rear side to the front side of the battery holder 5A in a state where the guide grooves 83 are engaged with the guide rails 52. That is, the installation direction of the battery 8 with respect to the battery holder 5A is the rear.

[0065] In addition, a hook engaging member 59 is disposed inside the rear portion of the housing 51. Moreover, the rear portion of the housing 51 protrudes more upward than other portions of the housing 51 because the hook engaging member 59 is housed therein. The hook engaging member 59 is configured to engage with the hook 85 when the hook 85 is disposed at the protruding position when the battery 8 is installed in the battery holder 5A. The rear end portion of the hook engaging member 59 is formed in an L shape when viewed from the side, and includes an engaging portion 591 that can abut against the rear end surface of the hook 85 from the rear side. The hook engaging member 59, like the terminal block 56, is sandwiched and held by the left member 511 and the right member 512. In addition, the hook engaging member 59 is formed of a metal (such as an iron alloy) to ensure strength.

[0066] Moreover, the housing 51 is configured as a member that engages with the outer shell 10 in a manner that it can move in the front-rear direction. Therefore, the left and right pair of side walls of the housing 51 have two pairs of left and right guide rails 53. That is, each side wall has two guide rails 53. The two guide rails are separately disposed in the up-down direction on the outer surface side of each side wall, and extend in the front-rear direction parallel to each other.

[0067] Next, the holding structure of the battery holder 5A on the housing 10 and the peripheral structure of the battery holder 5A will be described.

[0068] As Figure 2 and Figure 3 shown, the lower end portion of the rear end portion of the connecting portion 136 is configured as a holding portion 14A, and the holding portion 14A holds the battery holder 5A in a manner that allows it to move in the front-rear direction. The holding portion 14A is located below the gripping portion 131 (see Figure 1 ). The holding portion 14A includes a pair of left and right side walls 141 and a rear wall 145. In addition, the side walls 141 protrude more downward than the rear wall 145, and a housing space for the battery holder 5A is formed between the side walls 141.

[0069] As Figure 3 shown, the pair of left and right side walls 141 have a pair of left and right guide grooves 142 corresponding to the pair of left and right guide rails 53 of the battery holder 5A. More specifically, two guide grooves 142 that are separated and arranged in the vertical direction and extend in the front-rear direction in parallel with each other are formed on the inner surface side of the lower end portion of each side wall 141. The pair of left and right guide rails 53 of the battery holder 5A can be engaged with the pair of left and right guide grooves 142, so that the battery holder 5A can move linearly in the front-rear direction with respect to the housing 10. In addition, in the present embodiment, the housing 10 and the battery holder 5A are engaged through the pair of guide grooves 142 and the guide rails 52, thereby ensuring the strength of the engagement structure and maintaining a stable engagement state.

[0070] As Figure 2 shown, the lower end portion of the rear wall 145 is configured as an abutting portion 146, and when the battery 8 is mounted on the battery holder 5A, the abutting portion 146 abuts against and presses the hook 85. The abutting portion 146 has an inclined surface that slopes forward as it approaches the lower side. The inclination angle of the inclined surface of the abutting portion 146 is substantially the same as the inclination angle of the inclined surface of the hook 85 of the battery 8. A engaging portion 591 of the hook engaging member 59 of the battery holder 5A is disposed on the front side of the abutting portion 146. The lower end of the rear wall 145 and the lower end of the engaging portion 591 are located at substantially the same position in the vertical direction.

[0071] As Figure 2 and Figure 5As shown, a buffer member 6A is held at the rear side of the controller housing portion 138. The buffer member 6A is a member for cushioning impacts. When the battery 8 mounted on the battery holder 5A moves forward relative to the housing 10, the buffer member 6A abuts against the battery 8 and deforms, thereby cushioning the impact. In the present embodiment, the buffer member 6A is formed of rubber. More specifically, the buffer member 6A is connected to the rear wall of the controller housing portion 138 in such a manner as to face the front surface of the battery 8 when the battery 8 is mounted on the battery holder 5A. Two grooves 61 extending in the vertical direction are formed at the rear end portion of the buffer member 6A. The rear end surface of the buffer member 6A (the surface of the portion where the grooves 61 are not provided) has a shape substantially matching the front surface of the case 81 of the battery 8.

[0072] And, as Figure 2 shown, a biasing member 58 is disposed between the battery holder 5A and the housing 10. In the present embodiment, a compression coil spring is employed as the biasing member 58. Both end portions of the biasing member 58 are respectively fitted into a convex portion 517 protruding rearward from the center of the rear end portion of the case 51 of the battery holder 5A and a concave portion 139 provided in the controller housing portion 138. The biasing member 58 always biases the battery holder 5A and the controller housing portion 138 forward and rearward, respectively. Therefore, in the initial state where no external force is applied to the battery holder 5A in the forward direction, the rear wall of the case 51 is held at a position (hereinafter also referred to as the initial position) where it abuts against a stopper 143, and the stopper 143 is disposed on the inner surface side of the rear wall of the holding portion 14A. As Figure 2 and Figure 5 shown, when the battery holder 5A is in the initial position, the front surface of the battery 8 (specifically, the case 81) does not contact the rear end surface of the buffer member 6A and is slightly separated rearward from the rear end surface.

[0073] In addition, in the present embodiment, the biasing force of the biasing member 58 is set to satisfy the following two conditions. The first condition is that when the battery 8 is mounted, the biasing member 58 generates a biasing force that overcomes the pressing force in the rearward direction accompanying the mounting of the battery 8, and only allows a slight movement of the battery holder 5A within a range where the battery 8 does not abut against the buffer member 6A. The second condition is that when the battery holder 5A moves forward together with the battery 8 due to an impact during a fall, the biasing member 58 allows the battery holder 5A to move to an extent that the battery 8 elastically deforms the buffer member 6A.

[0074] Next, the mounting of the battery 8 relative to the battery holder 5A will be described.

[0075] First, the user engages the guide groove 83 of the battery 8 with the guide rail 52 of the battery holder 5A and slides the battery 8 linearly forward relative to the battery holder 5A. During the process in which the user slides the battery 8 forward, the hook 85 abuts against the abutting portion 146 of the holding portion 14A. More specifically, the inclined surface of the hook 85 abuts against the inclined surface of the abutting portion 146 from the rear. When the user further slides the battery 8 forward, the hook 85 is pressed from the protruding position to the retracted position by the abutting portion 146 in a state where the inclined surfaces are in contact with each other. In addition, in this way, by providing the abutting portion 146 on the housing 10, the hook 85 can be pressed more effectively compared to the case where it is provided on the battery holder 5A that moves relative to the housing 10 together with the battery 8.

[0076] When the user further slides the battery 8 forward and arranges the battery 8 at a specified position relative to the battery holder 5A, the terminals of the battery 8 are electrically connected to the terminals 55 of the battery holder 5A. In addition, the hook 85 returns to the protruding position and engages with the hook engaging member 59 in a state where the rear end surface of the hook 85 abuts against the engaging portion 591. Accordingly, the battery 8 is locked relative to the battery holder 5A, and thus the installation of the battery 8 is completed. In addition, since the applied force of the biasing member 58 is set as described above, the user can easily install the battery 8 on the battery holder 5A.

[0077] Next, the actions of the battery holder 5A and the buffer member 6A when the hammer drill 1A falls will be described.

[0078] When the hammer drill 1A falls, sometimes the part of the battery 8 that is not adjacent to the housing 10 (especially the rear end portion of the battery 8) collides with the ground or the floor prior to the housing 10. At this time, when the hammer drill 1A falls in a state where the center of gravity of the hammer drill 1A is located at the rear end portion of the battery 8 (in other words, in a posture where the center of gravity is directly above the rear end portion of the battery 8, or in a state where the entire weight of the hammer drill 1A acts on the rear end portion) and the rear end portion collides with the ground or the floor, a large impact force is applied to the rear end portion. The hammer drill 1A of the present embodiment is a relatively large and heavy impact tool among various power tools, and the battery 8 forms a part of the outer contour of the hammer drill 1A. Therefore, it is particularly easy to apply a large impact to the battery 8.

[0079] In addition, although detailed illustrations are omitted, the center of gravity of the hammer drill 1A with the battery 8 installed is located below the drive axis A1 and near the drive mechanism 3 and the motor 2. Therefore, when the hammer drill 1A falls in a state where the center of gravity is located at the rear end portion of the battery 8, an impact force including a forward component is applied to the battery 8.

[0080] In contrast, the battery 8 is mounted on a battery holder 5A that is movable in the front-rear direction relative to the housing 10. Further, in the front-rear direction, a buffer member 6A is interposed between the battery 8 and the housing 10 (controller housing portion 138). Thus, as Figure 6 shown, when the rear end portion of the battery 8 collides with the ground or the floor, the battery holder 5A slides forward relative to the housing 10 together with the battery 8, and the battery 8 collides with the buffer member 6A. The buffer member 6A absorbs the impact by elastic deformation, thereby reducing the possibility of damage to the battery 8. Thus, the hammer drill 1A of the present embodiment can effectively protect the battery 8 from external forces (in particular, the impact force when the hammer drill 1A falls with the center of gravity located at the rear end portion of the battery 8) through the battery holder 5A and the buffer member 6A.

[0081] Further, as described above, the battery holder 5A is biased in a direction away from the buffer member 6A (rearward) by a biasing member 58 and is held in the initial position as long as an external force in the opposite direction is not applied. In the initial position, the battery 8 mounted on the battery holder 5A does not contact the buffer member 6A. Accordingly, the buffering effect of the buffer member 6A when the battery holder 5A moves forward together with the battery 8 can be improved. Further, since the battery holder 5A and the holding portion 14A of the housing 10 are engaged with each other in a slidable state, the battery holder 5A can easily move relative to the housing 10 when the battery 8 is subjected to an external force.

[0082] Moreover, since the rear end portion of the buffer member 6A has two grooves 61, the buffer member 6A abuts against and deforms the front surface of the battery 8 at multiple locations (specifically, three regions on the rear surface). Compared with the case where the entire rear surface of the buffer member 6A contacts the front surface of the battery 8 (surface contact), the buffer member 6A having this shape is more easily deformed. Therefore, the buffer member 6A can more effectively absorb the impact.

[0083] Further, in the present embodiment, the hook 85 of the battery 8 is engaged not with the housing 10 but with a hook engaging member 59 (specifically, an engaging portion 591) of the battery holder 5A. Thus, even when the battery holder 5A moves relative to the housing 10 as described above, the engagement of the hook 85 can be stably maintained, and further, the mounting state of the battery 8 relative to the battery holder 5A can be stably maintained.

[0084] Next, with reference to Figure 7 and Figure 8 , a hammer drill 1B according to another embodiment will be described. The hammer drill 1B of the present embodiment has a structure similar to that of the above-described hammer drill 1A (refer to Figure 1 Figure 5) Different holding parts 14B, battery holder 5B, and buffer members 6B. Additionally, the hammer drill 1B does not have a biasing member 58 that biases the battery holder 5B. On the other hand, except for these differences, the structure of the hammer drill 1B is substantially the same as the structure of the hammer drill 1A (including cases where the shapes are slightly different). Therefore, in the following descriptions and the accompanying drawings, for structures that are substantially the same as those of the hammer drill 1A, the same reference numerals are used and their descriptions are simplified or omitted.

[0085] As Figure 7 and Figure 8 shown, in the present embodiment, the battery holder 5B is held by the buffer member 6B in a relatively movable manner in the holding part 14B.

[0086] The holding part 14B is the same as the holding part 14A of the first embodiment, and includes a pair of left and right side walls 141 and a rear wall 145 (refer to Figure 2 and Figure 3 ). On the other hand, different from the holding part 14A, two recesses 148 are provided on each side wall 141 instead of two guide grooves 142. The recess 148 is a bottomed recess with a circular cross-section.

[0087] The battery holder 5B is the same as the battery holder 5A of the first embodiment Figure 4 shown, and has a box body 51, terminals 55, a terminal base 56 for supporting the terminals 55, and a hook engaging member 59. The terminal base 56 and the hook engaging member 59 are clamped and held by the left side member 511 and the right side member 512 of the box body 51. A pair of guide rails 52 are provided at the lower end of the box body 51. That is, in the battery holder 5B, with respect to the engagement with and electrical connection to the battery 8, it has the same structure as the battery holder 5A.

[0088] On the other hand, as Figure 8 shown, different from the battery holder 5A, two cylindrical convex portions 54 are provided on the outer surface side of each side wall of the box body 51 of the battery holder 5B instead of the guide rails 53. The convex portion 54 has an outer diameter smaller than the diameter of the recess 148. The convex portion 54 projects into the recess 148 of the side wall 141. In addition, the protruding end of the convex portion 54 is slightly separated from the bottom of the recess 148.

[0089] In the present embodiment, four buffer members 6B are provided. Each buffer member 6B is a cylindrical member made of rubber. Each buffer member 6B is embedded in the outer periphery of the convex portion 54 and is embedded in the recess 148.

[0090] According to such a structure, the battery holder 5B is connected to the housing 10 (specifically, the second housing 13) through the buffer member 6B, and can move relative to the housing 10 not only in the front-rear direction but also in all directions intersecting the axis of the convex portion 54 (the axis extending in the left-right direction).

[0091] Next, the functions of the battery holder 5B and the buffer member 6B when the hammer drill 1B falls will be described.

[0092] When the hammer drill 1B falls, the battery holder 5B elastically deforms the buffer member 6B and moves relative to the housing 10 together with the battery 8. By the movement of the battery holder 5B relative to the housing 10, the impact on the battery 8 can be avoided. In addition, the buffer member 6B can absorb the impact. Thus, the hammer drill 1B of the present embodiment can effectively protect the battery 8 from external forces through the battery holder 5B and the buffer member 6B.

[0093] In addition, in the present embodiment, the battery holder 5B can move relative to the housing 10 in all directions intersecting the axis of the convex portion 54. Therefore, the battery 8 can be effectively protected from external forces from all directions. For example, when the hammer drill 1B falls in a state where the center of gravity is located at the rear end portion of the battery 8, the impact force applied to the battery 8 includes not only a component in the forward direction but also a component in the upward direction. Therefore, excellent effects can be achieved even for such an impact force.

[0094] The following shows the correspondence between the structural elements of the above-described embodiments and modification examples and the structural elements of the present invention. However, each structural element of the embodiment is only an example and does not limit the structural elements of the present invention.

[0095] The hammer drills 1A and 1B are examples of an "electric tool" and an "impact tool", respectively. The drive axis A1 is an example of a "drive axis". The motor 2 is an example of a "motor". The housing 10 is an example of a "housing". The battery holders 5A and 5B are examples of a "battery holder", respectively. The battery 8 is an example of a "battery". The buffer members 6A and 6B are examples of a "buffer member", respectively. The biasing member 58 is an example of a "biasing member". The terminals 55, the terminal block 56, the left-side member 511, and the right-side member 512 are examples of a "first terminal", a "terminal block", a "first member", and a "second member", respectively. The box body 81 and the hook 85 are examples of a "box body" and a "locking member", respectively. The engaging portion 591 is an example of an "engaging portion". The abutting portion 146 is an example of an "abutting portion".

[0096] The above embodiments are merely illustrative, and the power tools related to the present invention are not limited to the structures of the illustrated hammer drills 1A and 1B. For example, the following illustrated changes can be added. In addition, among these changes, only any one or more of them can be used in combination with the structures of the hammer drills 1A and 1B shown in the embodiments or the structural features described in each technical solution.

[0097] The structures (shape, size, material, structural elements, etc.) of the battery holders 5A and 5B can be appropriately changed. For example, the box body 51 may not be formed by connecting the left-side member 511 and the right-side member 512, but may be formed by connecting, for example, a front-side member and a rear-side member, or a lower-side member and a cover. Or, the box body 51 may be formed by more members. The terminal block 56 and the hook engaging member 59 may be held on the box body 51 not by clamping but by other means such as screws. In addition, the hook engaging member 59 may be configured to be omitted, and the rear wall of the box body 51 bears the hook 85 disposed at the protruding position.

[0098] The engaging structure between the battery holders 5A and 5B and the battery 8 is not limited to the sliding engagement structure of the guide rail 52 and the guide groove 83. For example, contrary to the above embodiments, guide grooves may be provided on the battery holders 5A and 5B, and guide rails may be provided on the battery 8. The number of the guide grooves and the guide rails can also be appropriately changed. In addition, for example, a protruding portion protruding linearly may be provided on one of the battery holders 5A and 5B and the battery 8, and a recess capable of engaging with the protruding portion may be provided on the other. In this case, the protruding direction of the protruding portion defines the disassembly and assembly direction of the battery 8. The disassembly and assembly direction of the battery 8 relative to the battery holders 5A and 5B may be, for example, the left-right direction or the up-down direction.

[0099] The engaging structure between the battery holders 5A and 5B and the housing 10 can also be appropriately changed. For example, contrary to the example of the hammer drill 1A, a guide groove may be provided on the battery holder 5A, and a guide rail may be provided on the holding portion 14A. In addition, the number and the arrangement position of the guide groove and the guide rail can be appropriately changed. In addition, contrary to the example of the hammer drill 1B, a recess may be provided on the battery holder 5B, and a convex portion and a buffer member may be provided on the holding portion 14B. The number and the arrangement position of the recess, the convex portion, and the buffer member can also be appropriately changed. The moving direction of the battery holders 5A and 5B relative to the housing 10 is not limited to the examples of the above embodiments. In addition, the arrangement position of the buffer member 6A can also be changed according to the change in the moving direction. However, in a state where the center of gravity is located at a part of the battery 8, the moving direction is set according to the direction of the impact force when the hammer drills 1A and 1B fall.

[0100] The shapes, numbers, and materials of the buffer members 6A and 6B are not limited to the examples of the above-described embodiments. For example, a plurality of buffer members may be provided on the hammer drill 1A instead of one buffer member 6A. In this case, for example, the plurality of buffer members may be held on the rear wall of the controller housing portion 138 so as to be separated from each other in the left-right direction (or up-down direction). Similar to the hammer drill 1A, a buffer member 6A may also be provided on the hammer drill 1B. In addition, the buffer members 6A and 6B may be formed of an elastic material other than rubber (for example, an elastic synthetic resin (such as polyurethane foam), etc.).

[0101] Regarding the structures, arrangements of the internal structures of the motor 2, the drive mechanism 3, the controller 151, etc., and the structure of the housing 10 that houses these components, appropriate changes can also be made. In addition, the arrangements of the battery holders 5A and 5B can also be changed according to the changes in the housing 10.

[0102] For example, the motor 2 may be arranged such that the rotation axis of the motor shaft 25 extends parallel to the drive axis A1. The motion conversion mechanism 30 may not be a crank mechanism, but a swing member type motion conversion mechanism.

[0103] The shapes of the first housing 11 and the second housing 13, the structures, numbers, and arrangement positions of the elastic structural elements (elastic members 121 and 123) between the first housing 11 and the second housing 13, etc. can be appropriately changed. For example, a C-shaped handle including a grip portion may be elastically connected to the rear end portion of the L-shaped first housing 11. In this case, for example, holding portions 14A and 14B may be provided at the lower end portion of the motor housing portion 17 of the first housing 11 to hold the battery holders 5A and 5B. In addition, when the battery holder 5A is adopted, the buffer member 6A may be held at the lower end portion of the motor housing portion 117. In addition, as described above, when the rotation axis of the motor shaft 25 is arranged to extend parallel to the drive axis A1, the first housing 11 may be configured to extend along the drive axis A1, and the upper end portion of the handle including only the grip portion is elastically connected to the first housing 11 in a cantilever manner. In this case, similar to the above case, holding portions 14A and 14B may be provided at the lower end portion of the handle to hold the battery holder 5A and 5B.

[0104] Moreover, the power tools according to the present invention are not limited to the hammer drills 1A and 1B as an example of impact tools. A power tool is a general tool that operates using electric power supplied by a battery and is used for work and the like. For example, the power tool according to the present invention can be embodied as an impact tool other than a hammer drill (for example, a rotary hammer). Alternatively, it can be embodied as a so-called rotary tool (for example, a shear wrench) configured to drive a final output shaft to rotate. Depending on the type of power tool, the structure and arrangement of the housing 10 and the internal structure disposed within the housing 10 can be appropriately changed.

[0105] Moreover, in view of the gist of the present invention and the above-described embodiments and their modifications, the following modes are constructed. The following modes can be used independently or in combination with the hammer drills 1A and 1B shown in the embodiments, the above-described modifications, other modes, or the technical solutions recited in the respective claims.

[0106] [Mode 1]

[0107] The moving direction of the battery holder relative to the housing is substantially parallel to the direction of attachment and detachment of the battery relative to the battery holder.

[0108] [Mode 2]

[0109] The moving direction of the battery holder is a direction substantially parallel to the drive axis.

[0110] [Mode 3]

[0111] It further includes a drive mechanism configured to linearly drive a tip tool along a drive axis by the power of the motor.

[0112] The housing includes a first part, a second part, and a third part, wherein

[0113] The first part extends along the drive axis and has a first end and a second end;

[0114] The second part projects from the first end of the first part in a direction intersecting the drive axis;

[0115] The third part extends from a portion of the second part closer to the first part than the projecting side end in a direction opposite to the second end in a manner substantially parallel to the drive axis.

[0116] The drive mechanism is housed in the first part.

[0117] The motor is housed in the second part with the rotational axis of the motor shaft intersecting the drive axis.

[0118] The battery holder is held in the third part.

[0119] When the battery is installed in the battery holder, the battery is arranged so as to face the end portion of the protruding side of the second part in the extending direction of the drive axis.

[0120] The drive mechanism housing portion 111 is an example of the "first part" in this mode. The rear end portion and the front end portion of the drive mechanism housing portion 111 are examples of the "first end portion" and the "second end portion", respectively. The motor housing portion 117 and the controller housing portion 138 as a whole are an example of the "second part". The lower end portion of the controller housing portion 138 is an example of the "end portion of the protruding side". The connecting portion 136 is an example of the "third part".

[0121] [Mode 4]

[0122] In Mode 3,

[0123] The buffer member is held at the end portion of the protruding side of the second part.

[0124] [Mode 5]

[0125] It further includes a drive mechanism and a controller, wherein,

[0126] The drive mechanism is configured to linearly drive the tip tool along the drive axis by the power of the motor;

[0127] The controller is configured to control the drive of the motor,

[0128] The housing includes a first housing and a second housing that are elastically connected to each other,

[0129] The first housing includes a drive mechanism housing portion and a motor housing portion, wherein,

[0130] The drive mechanism housing portion extends along the drive axis and houses the drive mechanism;

[0131] The motor housing portion protrudes from one end portion of the drive mechanism housing portion in a first direction intersecting the drive axis and houses the motor,

[0132] The second housing includes a grip portion, a cover portion, a controller housing portion, and a connecting portion, wherein,

[0133] The grip portion extends in the first direction;

[0134] The cover portion extends from one end portion of the grip portion substantially parallel to the drive axis and covers at least a part of the drive mechanism housing portion;

[0135] The controller housing portion is disposed in the first direction, on a side opposite to the motor housing portion and the drive mechanism housing portion, and houses the controller;

[0136] The connecting portion extends substantially parallel to the drive axis from the other end of the gripping portion, and connects the gripping portion and the controller housing portion.

[0137] The battery holder is held by the connecting portion.

[0138] When the battery is mounted on the battery holder, the battery is arranged to face the controller housing portion in the extending direction of the drive shaft.

[0139] The drive mechanism 3 is an example of the "drive mechanism" in this mode. The controller 151 is an example of the "controller" in this mode. The first housing 11 and the second housing 13 are examples of the "first housing" and the "second housing" in this mode respectively. The drive mechanism housing portion 111 is an example of the "first part" in this mode. The motor housing portion 117 is an example of the "motor housing portion" in this mode. The gripping portion 131, the upper side portion 133, the controller housing portion 138 and the connecting portion 136 are examples of the "gripping portion", the "cover member", the "controller housing portion" and the "connecting portion" in this mode respectively.

[0140] [Mode 6]

[0141] In Mode 5,

[0142] The buffer member is held by the controller housing portion.

Claims

1. An electric tool, characterized in that, it has a motor, a housing, a battery holder, a buffer member and a biasing member, wherein, the motor is used to drive the tip tool; the housing is used to accommodate the motor; the battery holder is configured to be detachable for supplying electric power to the motor, and is held by the housing in a state capable of relative movement with respect to the housing; the buffer member is held by the housing in such a way that a surface facing the battery in a state of being mounted on the battery holder intersects the moving direction of the battery holder; the biasing member biases the battery holder in the moving direction of the battery holder in a direction away from the buffer member; the buffer member is disposed between the battery and the housing when the battery is mounted on the battery holder, and absorbs an impact on the battery by elastic deformation; the battery holder is held at the initial position by the biasing force of the biasing member in the case where an external force in a direction approaching the buffer member is not applied; the buffer member is configured to be separated from the battery mounted on the battery holder when the battery holder is at the initial position, and to come into contact with the battery as the battery holder moves from the initial position due to an impact when the electric tool falls.

2. The electric tool according to claim 1, characterized in that, the housing and the battery holder are engaged with each other in a relatively slidable state; at least one of the housing and the battery holder has at least one guide rail extending in a first direction, and the other of the housing and the battery holder has at least one groove extending in the first direction and engaging with the at least one guide rail in a slidable manner.

3. The electric tool according to claim 1 or 2, characterized in that, the battery holder has: a first terminal capable of being electrically connected to a second terminal of the battery; a terminal block for supporting the first terminal; and a first member and a second member that sandwich the terminal block to hold it, the first member and the second member are separate members and are connected to each other in a state of sandwiching the terminal block.

4. The electric tool according to claim 1 or 2, characterized in that, the battery has a case and a locking member that can move between a first position protruding from the case and a second position protruding less from the case than the first position; the battery holder has an engaging portion that can engage with the locking member disposed at the first position; the housing has an abutting portion configured to abut against the locking member and move the locking member from the first position to the second position during the process of mounting the battery on the battery holder.

5. The electric tool according to claim 1 or 2, characterized in that, the buffer member is configured to be able to abut against the battery at multiple locations.

6. The electric tool according to claim 1 or 2, characterized in that, The buffer member is disposed on the traveling direction side of the battery when the battery is installed in the battery holder.

7. The power tool according to claim 1 or 2, characterized in that the power tool is an impact tool configured to linearly drive a tip tool along a drive axis by the power of the motor, when the battery is installed on the battery holder, a part of the battery forms a part of the outer contour of the impact tool.

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