JP7465647B2 - Hammer Drill - Google Patents

Description

The present invention relates to a hammer drill that can perform the operation of driving a tool tip in a linear manner and the operation of driving a tool tip in rotation.

A hammer drill is configured to be capable of performing a hammering operation in which a tool tip attached to a tool holder is driven linearly along a drive shaft, and a drilling operation in which a tool tip is driven in rotation around the drive shaft. Generally, a motion conversion mechanism that converts the rotational motion of an intermediate shaft into linear motion is used for the hammering operation, and a rotation transmission mechanism that transmits torque to the tool holder via the intermediate shaft is used for the drilling operation. For example, in the hammer drill disclosed in Patent Document 1, separate intermediate shafts are provided for the motion conversion mechanism and the rotation transmission mechanism.

European Patent No. 2700477

In the hammer drill of Patent Document 1, the intermediate shaft of the rotation transmission mechanism first rotates the spindle, which serves as the final output shaft, at a reduced speed, and then the spindle rotates the intermediate shaft of the motion conversion mechanism at an increased speed, which can result in reduced efficiency.

In view of this situation, the present invention aims to provide technology that can contribute to improving the efficiency of power transmission in a hammer drill equipped with two intermediate shafts.

According to one aspect of the present invention, a hammer drill is provided that includes a final output shaft, a motor, a first intermediate shaft, a first drive mechanism, a second intermediate shaft, and a second drive mechanism.

The final output shaft is configured to removably hold the tool bit. The final output shaft is rotatably arranged around the drive shaft. The motor has a motor shaft extending in a direction intersecting the drive shaft. The first intermediate shaft extends parallel to the drive shaft. The first drive mechanism is configured to perform a hammering operation. The hammering operation is an operation in which the rotational motion of the first intermediate shaft is converted into linear motion and the tool bit is driven linearly along the drive shaft. The second intermediate shaft extends parallel to the drive shaft. The second drive mechanism is configured to perform a drilling operation. The drilling operation is an operation in which the rotation of the second intermediate shaft is transmitted to the final output shaft and the tool bit is driven to rotate around the drive shaft.

Furthermore, the motor shaft is configured to rotate one of the first intermediate shaft and the second intermediate shaft via a pair of bevel gears. One of the first intermediate shaft and the second intermediate shaft is configured to rotate the other of the first intermediate shaft and the second intermediate shaft via a pair of gears.

In the hammer drill of this embodiment, the final output shaft, the first intermediate shaft for the first drive mechanism that performs the hammering operation, and the second intermediate shaft for the second drive mechanism that performs the drilling operation extend parallel to each other. Meanwhile, the motor shaft extends in a direction intersecting with the final output shaft. The rotation of the motor shaft is first transmitted to one of the first and second intermediate shafts via a pair of bevel gears, and is then transmitted to the other intermediate shaft via a pair of gears. With this configuration, the final output shaft is not interposed in the transmission path between the first and second intermediate shafts, so there is no need for unnecessary deceleration or acceleration, and efficient transmission can be achieved.

In one aspect of the present invention, the motor shaft may be configured to rotate the first intermediate shaft. The first intermediate shaft may be configured to rotate the second intermediate shaft. In this case, torque is transmitted directly from the motor shaft to the first intermediate shaft, which receives the load due to the hammering action, which is preferable.

In one aspect of the present invention, the first drive mechanism may include a motion conversion member disposed on the first intermediate shaft and configured to convert the rotational motion of the first intermediate shaft into linear motion. One of the pair of bevel gears may be provided on the first intermediate shaft adjacent to a bearing that rotatably supports one end of the first intermediate shaft. One of the pair of gears may be disposed on the first intermediate shaft between one of the pair of bevel gears and the motion conversion member. In this case, the arrangement area of the bevel gears and the gears can be made compact in the axial direction of the first intermediate shaft. In addition, by concentrating the gears near the bearing that has little deflection, the meshing between the pair of bevel gears and between the pair of gears can be maintained with high precision.

In one aspect of the present invention, the hammer drill may further include a torque limiter disposed on the second intermediate shaft and configured to cut off transmission when the torque acting on the second intermediate shaft exceeds a threshold value. By providing a first intermediate shaft for the first drive mechanism that performs the hammering operation and a second intermediate shaft for the first drive mechanism that performs the drilling operation separately, space is likely to be generated on the second intermediate shaft. Therefore, this space can be effectively utilized to realize a rational arrangement of the torque limiter.

In one aspect of the present invention, the rotation axis of the motor shaft and the rotation axis of one of the first intermediate shaft and the second intermediate shaft may be on the same plane. In this case, since these rotation axes are not offset from each other, a bevel gear with a simple configuration can be used. In this aspect, it is preferable that the drive shaft is also on the same plane. Furthermore, if the extension direction of the drive shaft is defined as the front-rear direction of the hammer drill, the direction perpendicular to the drive shaft and corresponding to the extension direction of the motor shaft is defined as the up-down direction, the direction perpendicular to the front-rear direction and the up-down direction is defined as the left-right direction, and further, in the front-rear direction, the side where the tool tip is attached is defined as the front side, and in the up-down direction, the side where the motor is located relative to the drive shaft is defined as the lower side, the other rotation axis of the first intermediate shaft and the second intermediate shaft may be located on the left side of the above plane when facing forward.

In one aspect of the present invention, the hammer drill may further include a first clutch mechanism and a second clutch mechanism. The first clutch mechanism is provided on the first intermediate shaft and configured to transmit or interrupt power for the hammer operation. The second clutch mechanism is provided on the second intermediate shaft and configured to transmit or interrupt power for the drill operation. In this case, the first clutch mechanism and the second clutch mechanism can be used to respectively interrupt the power for the hammer operation and the power for the drill operation as needed.

In this aspect, the hammer drill may further include an operating member for switching the operation mode of the hammer drill. The operating member may be configured to be manually operable by a user. Furthermore, both the first clutch mechanism and the second clutch mechanism may be configured to be switched between a power transmission state and a cut-off state in response to the operation of the operating member. In this case, the user can operate the first clutch mechanism and the second clutch mechanism simply by operating a single operating member in response to a desired task and switching the operation mode.

FIG. 2 is a cross-sectional view taken along line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. 4 is a cross-sectional view taken along line IV-IV in FIG. 2. FIG. 2 is a partially enlarged view of FIG. FIG. 13 is a diagram showing the internal structure of the drive mechanism housing as viewed in the direction of the rotation axis of the mode switching dial, illustrating the mode switching mechanism when the hammer drill mode is selected. 13 is an explanatory diagram of the mode switching mechanism when the hammer mode is selected. FIG. FIG. 13 is an explanatory diagram of the mode switching mechanism when the drill mode is selected.

Below, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a hammer drill 101 is illustrated as an example of an impact tool. The hammer drill 101 is a handheld power tool used for machining operations such as chipping and drilling, and is configured to be able to perform an operation of driving the tip tool 91 linearly along a predetermined drive axis A1 (hereinafter referred to as a hammering operation), and an operation of driving the tip tool 91 in rotation around the drive axis A1 (hereinafter referred to as a drilling operation).

First, the schematic configuration of the hammer drill 101 will be briefly described with reference to Figure 1. As shown in Figure 1, the outer shell of the hammer drill 101 is mainly formed by the main body housing 10 and a handle 15 connected to the main body housing 10.

The main body housing 10 is a hollow body also referred to as a tool main body or an outer housing, and houses the spindle 31, the drive mechanism 5, the motor 2, etc. The spindle 31 is a long cylindrical member. The spindle 31 is provided at one end in the axial direction with a tool holder 32 that removably holds the tip tool 91. The long axis of the spindle 31 defines the drive axis A1 of the tip tool 91.
In this embodiment, the main body housing 10 is formed in a generally L-shape in a side view. The main body housing 10 includes two parts: a drive mechanism housing section 11 that houses the spindle 31 and the drive mechanism 5, and a motor housing section 12 that houses the motor 2. The drive mechanism housing section 11 extends along the drive axis A1. The tool holder 32 is disposed in one end of the drive mechanism housing section 11 in the extension direction of the drive axis A1 (hereinafter, simply referred to as the drive axis direction). The motor housing section 12 protrudes obliquely from the other end of the drive mechanism housing section 11 in the drive axis direction in a direction away from the drive axis A1. The motor 2 is disposed in the motor housing section 12 so that the rotation axis A2 of the motor shaft 25 extends in a direction intersecting the drive axis A1 (specifically, in a diagonal direction with respect to the drive axis A1).

For the sake of convenience, in the following description, the extension direction of the drive shaft A1 is defined as the front-rear direction of the hammer drill 101. In the front-rear direction, the end side where the tool holder 32 is arranged is defined as the front side of the hammer drill 101, and the opposite side is defined as the rear side. In addition, the direction perpendicular to the drive shaft A1 and corresponding to the extension direction of the rotation axis A2 of the motor shaft 25 is defined as the up-down direction of the hammer drill 1. In the up-down direction, the direction in which the motor housing 12 protrudes from the drive mechanism housing 11 is defined as the downward direction, and the opposite direction is defined as the upward direction. Furthermore, the direction perpendicular to the front-rear direction and the up-down direction is defined as the left-right direction.

The handle 15 is generally formed in a roughly C-shape in side view, and both ends are connected to the main housing 10. The handle 15 includes a long, cylindrical grip 16 and a rectangular box-shaped controller housing 17 connected to the lower side of the grip 16. The grip 16 is a portion that is gripped by the user, is disposed at a distance from the rear of the main housing 10, and extends generally in the vertical direction so as to intersect with the drive axis A1. A trigger 161 that can be pressed (pulled) by the user is provided at the front of the upper end of the grip 16. A switch 162 that is turned on in response to pressing the trigger 161 is provided inside the grip 16. The controller housing 17 houses a controller 171 for controlling the drive of the motor 2. A battery attachment section 173 is provided at the lower end of the controller housing 17 to which a rechargeable battery (battery pack) 93 can be attached and detached as a power source for the motor 2, etc.

In this embodiment, the handle 15 is elastically connected to the main housing 10 so as to be movable relative to the main housing 10. Specifically, the lower end of the handle 15 is disposed within the lower end of the motor housing 12 and is supported so as to be rotatable about a rotation axis extending in the left-right direction. The upper end of the handle 15 is connected to the rear end of the drive mechanism housing 11 via a biasing spring so as to be movable in the front-rear direction.

In the hammer drill 1, when the trigger 161 is pulled and the switch 162 is turned on, the motor 2 is energized by the controller 171, and the hammer operation and/or drill operation is performed.

The detailed configuration of the hammer drill 101 is described below.

First, we will explain the configuration and internal structure of the main body housing 10 (motor housing section 12 and drive mechanism housing section 11).

As shown in FIG. 1, the motor housing 12 is a portion of the main body housing 10 that is connected to the rear end of the drive mechanism housing 11 and extends downward. The motor housing 12 houses the motor 2. In this embodiment, a DC brushless motor is used for the motor 2. The motor 2 includes a main body 20 including a stator and a rotor, and a motor shaft 25 configured to rotate integrally with the rotor. The motor shaft 25 is supported by bearings 251 and 252 to be rotatable around a rotation axis A2 relative to the main body housing 10. The rotation axis A2 extends diagonally downward and forward relative to the drive axis A1. The upper end of the motor shaft 25 protrudes into the drive mechanism housing 11. A drive bevel gear 255 is fixed to the upper end of the motor shaft 25.

As shown in FIG. 1, the drive mechanism accommodating section 11 is a portion of the main body housing 10 that extends along the drive axis A1 and accommodates the spindle 31 and drive mechanism 5. The drive mechanism accommodating section 11 has a cylindrical front end. This cylindrical portion is called the barrel section 111. The portion of the drive mechanism accommodating section 11 other than the barrel section 111 is formed in a roughly rectangular box shape. An auxiliary handle (not shown) can be attached to the barrel section 111. In addition to the handle 15, the user can also hold the auxiliary handle attached to the barrel section 111 as an auxiliary grip.

The spindle 31 is the final output shaft of the hammer drill 101. The spindle 31 is supported by bearings 316 and 317 to be rotatable around the drive axis A1 relative to the main housing 10. The front half of the spindle 31 constitutes a tool holder 32 to which the tip tool 91 can be attached and detached. The tip tool 91 is inserted into the tool holder 32 so that its long axis coincides with the drive axis A1, and is held in a state in which axial movement relative to the tool holder 32 is permitted and rotation around the axis is restricted. The rear half of the spindle 31 constitutes a cylinder 33 that slidably holds a piston 65 (described later). In this embodiment, the spindle 31 is a single member in which the tool holder 32 and the cylinder 33 are integrally formed, but may be formed by connecting multiple members.

The drive mechanism 5 includes a striking mechanism 6 configured to perform a hammering operation, and a rotation transmission mechanism 7 (see FIG. 3) configured to perform a drilling operation. In this embodiment, the power of the motor 2 is transmitted to the striking mechanism 6 via a first intermediate shaft 41, and to the rotation transmission mechanism 7 via a second intermediate shaft 42. In other words, the hammer drill 101 has two separate intermediate shafts for the striking mechanism 6 and the rotation transmission mechanism 7.

Here, we will explain the arrangement of the first intermediate shaft 41 and the second intermediate shaft 42.

As shown in Figures 1 to 4, both the first intermediate shaft 41 and the second intermediate shaft 42 extend parallel to the drive axis A1 within the drive mechanism accommodating section 11. As shown in Figure 3, the first intermediate shaft 41 is supported rotatably about the rotation axis A3 relative to the main housing 10 via two bearings 411 and 412. Similarly, the second intermediate shaft 42 is supported rotatably about the rotation axis A4 relative to the main housing 10 via two bearings 421 and 422.

As shown in FIG. 2, in this embodiment, the rotation axis A3 of the first intermediate shaft 41 extends directly below the drive shaft A1 and parallel to the drive shaft A1. Furthermore, the rotation axis A3, the drive shaft A1, and the rotation axis A2 of the motor shaft 25 are all on the same plane (hereinafter referred to as the reference plane P). The reference plane P extends in the vertical direction of the hammer drill 101. On the other hand, the rotation axis A4 of the second intermediate shaft 42 is located to the left of the reference plane P.

As shown in Figures 3 and 5, a driven bevel gear 414 is fixed to the rear end of the first intermediate shaft 41 adjacent to the front side of the bearing 412. The driven bevel gear 414 meshes with the drive bevel gear 255 of the motor shaft 25. Thus, the rotation of the motor shaft 25 is transmitted to the first intermediate shaft 41 via the drive bevel gear 255 and the driven bevel gear 414.

In this embodiment, the rotation axis A3 of the first intermediate shaft 41 and the rotation axis A2 of the motor shaft 25 are both on the reference plane P and intersect with each other. More specifically, the rotation axis A2 and the rotation axis A3 intersect at an acute angle. For this reason, in this embodiment, straight bevel gears that are simply configured and relatively inexpensive are used as the drive bevel gear 255 and the driven bevel gear 414. However, other types of intersecting axis gears (e.g., spiral bevel gears) may also be used. The drive bevel gear 255 and the driven bevel gear 414 form a reduction gear mechanism.

Furthermore, as shown in FIG. 3, a drive gear 415 is fixed to the rear end of the first intermediate shaft 41 adjacent to the front side of the driven bevel gear 414. On the other hand, a gear member 423 having a driven gear 424 is disposed at the rear end of the second intermediate shaft 42 adjacent to the front side of the bearing 422. The driven gear 424 is meshed with the drive gear 415. Thus, the rotation of the first intermediate shaft 41 is transmitted to the gear member 423 via the drive gear 415 and the driven gear 424. In this embodiment, the drive gear 415 and the driven gear 424 have the same diameter. In addition, a spur gear with a simple configuration and relatively low cost is used as the drive gear 415 and the driven gear 424. However, other types of parallel shaft gears (e.g., helical gears) may be used.

The gear member 423 is cylindrical and is disposed on the outer periphery of the second intermediate shaft 42 (more specifically, the drive side member 74 described below). A spline portion 425 is provided on the outer periphery of the cylindrical front end of the gear member 423. The spline portion 425 has a plurality of splines (external teeth) extending in the direction of the rotation axis A4 (front-rear direction). The rotation of the gear member 423 is transmitted to the second intermediate shaft 42 via the second transmission member 72 and the torque limiter 73, which will be described in detail later.

The detailed configuration of the impact mechanism 6 and the rotation transmission mechanism 7 will be explained below.

The impact mechanism 6 is a mechanism for performing a hammering operation, and is configured to convert the rotational motion of the first intermediate shaft 41 into linear motion and drive the tip tool 91 linearly along the drive axis A1. In this embodiment, as shown in Figures 1 and 5, the impact mechanism 6 includes a motion conversion member 61, a piston 65, a striker 67, and an impact bolt 68.

The motion conversion member 61 is disposed on the first intermediate shaft 41 and is configured to convert the rotational motion of the first intermediate shaft 41 into linear motion and transmit it to the piston 65. More specifically, the motion conversion member 61 includes a rotating body 611 and a swinging member 616.

The rotating body 611 is supported by a bearing 614 so as to be rotatable around the rotation axis A3 relative to the main housing 10. In this embodiment, a cylindrical intervening member 63 is interposed between the rotating body 611 and the first intermediate shaft 41. The intervening member 63 is configured to be immovable in the front-rear direction relative to the first intermediate shaft 41 and to be rotatable integrally with the rotating body 611 relative to the first intermediate shaft 41. The front end of the intervening member 63 protrudes forward from the front end of the rotating body 611. The oscillating member 616 is rotatably attached to the outer periphery of the rotating body 611 and is configured to oscillate in the extension direction of the rotation axis A3 (front-rear direction) as the rotating body 611 rotates. The oscillating member 616 has an arm portion 617 extending upward from the rotating body 611.

The piston 65 is a cylindrical member with a bottom, and is disposed within the cylinder 33 of the spindle 31 so as to be able to slide along the drive axis A1. The piston 65 is connected to the arm portion 617 of the oscillating member 616 via a connecting pin, and is reciprocated in the front-rear direction in association with the oscillation of the oscillating member 616.

The striker 67 is a striking element for applying a striking force to the tip tool 91. The striker 67 is arranged inside the piston 65 so as to be slidable along the drive axis A1. The internal space of the piston 65 behind the striker 67 is defined as an air chamber that functions as an air spring. The impact bolt 68 is an intermediate element that transmits the kinetic energy of the striker 67 to the tip tool 91. The impact bolt 68 is arranged in front of the striker 67 inside the tool holder 32 so as to be movable along the drive axis A1.

When the piston 65 moves forward and backward with the swinging member 616, the air pressure in the air chamber fluctuates, and the striker 67 slides forward and backward inside the piston 65 due to the action of the air spring. More specifically, when the piston 65 moves forward, the air in the air chamber is compressed and the internal pressure rises. The striker 67 is pushed forward at high speed by the action of the air spring and strikes the impact bolt 68. The impact bolt 68 transmits the kinetic energy of the striker 67 to the tip tool 91. As a result, the tip tool 91 is driven linearly along the drive axis A1. On the other hand, when the piston 65 moves backward, the air in the air chamber expands, the internal pressure drops, and the striker 67 is pulled backward. The tip tool 91 is pressed against the workpiece and moves backward together with the impact bolt 68. In this way, the hammering action is repeated by the impact mechanism 6.

In this embodiment, the rotation of the first intermediate shaft 41 is transmitted to the motion conversion member 61 (specifically, the rotating body 611) via the first transmission member 64 and the intervening member 63.

The first transmission member 64 is disposed on the first intermediate shaft 41 and is configured to be rotatable integrally with the first intermediate shaft 41 and to be movable in the direction of the rotation axis A3 (front-rear direction) relative to the first intermediate shaft 41 and the intervening member 63. More specifically, the inner circumference of the first transmission member 64 is provided with a first spline portion 641 that can engage with the intervening member 63, and a second spline portion 642 that always engages with the first intermediate shaft 41.

The first spline portion 641 is provided on the inner circumference of the rear end portion of the first transmission member 64. The first spline portion 641 has a plurality of splines (internal teeth) extending in the direction of the rotation axis A3 (front-rear direction). Meanwhile, the spline portion 631 is provided on the outer circumference of the front end portion of the intervening member 63. The spline portion 631 has a plurality of splines (external teeth) that can engage with the first spline portion 641.

The second spline portion 642 is provided on the inner circumference of the front half of the first transmission member 64. The second spline portion 642 has a plurality of splines (internal teeth) extending in the direction of the rotation axis A3 (front-rear direction). On the other hand, the front end portion (the portion adjacent to the rear side of the front bearing 411) of the first intermediate shaft 41 is configured as a large diameter portion. The spline portion 416 is provided on the outer periphery of the large diameter portion. The spline portion 416 has a plurality of splines (external teeth) that constantly engage with the second spline portion 642.

With this configuration, as shown by the solid line in Figure 5, when the first spline portion 641 is disposed in a position (hereinafter referred to as the engaged position) in which it engages with the spline portion 631 of the intervening member 63 in the front-rear direction, the first transmission member 64 can rotate integrally with the intervening member 63 and the rotating body 611, that is, it can transmit power from the first intermediate shaft 41 to the motion conversion member 61. On the other hand, as shown by the dotted line in Figure 5, when the first spline portion 641 is disposed in a position (hereinafter referred to as the separated position) in which it is separated from the spline portion 631 (cannot be engaged), the first transmission member 64 disables (cuts off) the transmission of power from the first intermediate shaft 41 to the motion conversion member 61.

As described above, in this embodiment, the first transmission member 64 and the intervening member 63 function as a first clutch mechanism 62 that transmits or cuts off the power for the hammer operation. In this embodiment, the first transmission member 64 is connected to a mode switching mechanism 80 (see FIG. 6) and is moved between an engaged position and a disengaged position in response to the operation of the mode switching dial 800 (see FIGS. 2 and 4) by the user. In other words, the first clutch mechanism 62 is switched between a power transmission state and a cut-off state in response to the operation of the mode switching dial 800. The mode switching mechanism 80 will be described in detail later.

The rotation transmission mechanism 7 is a mechanism for performing a drilling operation, and is configured to transmit the rotation of the second intermediate shaft 42 to the spindle 31 and rotate the tip tool 91 around the drive axis A1. As shown in FIG. 4, in this embodiment, the rotation transmission mechanism 7 includes a drive gear 78 and a driven gear 79. The drive gear 78 is fixed to the front end of the second intermediate shaft 42 (the part adjacent to the rear side of the front bearing 421). The driven gear 79 is fixed to the outer periphery of the cylinder 33 of the spindle 31 and meshes with the drive gear 78. The drive gear 78 and the driven gear 79 form a gear reduction mechanism. As the drive gear 78 rotates integrally with the second intermediate shaft 42, the spindle 31 rotates integrally with the driven gear 79. As a result, a drilling operation is performed in which the tip tool 91 held by the tool holder 32 is rotated around the drive axis A1.

As described above, in this embodiment, the rotation of the driven gear 424, which rotates in conjunction with the rotation of the motor shaft 25, is transmitted to the second intermediate shaft 42 via the second transmission member 72 and the torque limiter 73. The torque limiter 73 and the second transmission member 72 will be described in order below.

As shown in Figs. 3 and 4, the torque limiter 73 is a safety clutch mechanism disposed on the second intermediate shaft 42 and configured to cut off transmission when the torque acting on the second intermediate shaft 42 exceeds a threshold value. In this embodiment, the torque limiter 73 includes a driving member 74, a driven member 75, a ball 76, and a biasing spring 77.

The driving side member 74 is a cylindrical member and is rotatably supported by the rear half of the second intermediate shaft 42. The driven gear 424 is rotatably supported by the rear end of the driving side member 74. Therefore, the driving side member 74 can rotate around the rotation axis A4 relative to the second intermediate shaft 42 and the driven gear 424.

The driving side member 74 includes a cam recess 742 (see FIG. 4) and a spline portion 743. The cam recess 742 is provided at the front end of the driving side member 74. Although detailed illustration is omitted, the cam recess 742 has a cam surface that is inclined in the circumferential direction. The spline portion 743 is provided on the outer periphery of the driving side member 74 behind the cam recess 742, and has a plurality of splines (external teeth) that extend in the direction of the rotation axis A4 (front-rear direction).

The driven member 75 is a cylindrical member and is disposed around the second intermediate shaft 42 in front of the driving member 74. The driven member 75 has a plurality of grooves extending in the direction of the rotation axis A4 (front-rear direction) in the circumferential direction on its inner circumference. The second intermediate shaft 42 has a plurality of grooves extending in the direction of the rotation axis A4 (front-rear direction) in the circumferential direction on its outer circumference. The balls 76 are rollably accommodated in the raceways defined by these grooves. As a result, the driven member 75 engages with the second intermediate shaft 42 via the balls 76 in the radial and circumferential directions, and is capable of rotating integrally with the second intermediate shaft 42. The driven member 75 is movable in the front-rear direction relative to the second intermediate shaft 42 within the range in which the balls 76 can roll in the raceways.

The driven member 75 has a cam protrusion 752 (see FIG. 4) provided at the rear end. Although detailed illustration is omitted, the cam protrusion 752 has a shape that generally matches the cam recess 742 of the driving member 74, and has a cam surface that is inclined in the circumferential direction. The biasing spring 77 is a compression coil spring and is arranged in a compressed state between the driving gear 78 and the driven member 75. For this reason, the biasing spring 77 always biases the driven member 75 in a direction approaching the driving member 74, that is, in a direction in which the cam protrusion 752 and the cam recess 742 mesh (rearward). When the cam protrusion 752 and the cam recess 742 are meshed and engaged, torque transmission from the driving member 74 to the driven member 75, and thus rotation of the second intermediate shaft 42, are possible. The driving member 74 and the gear member 423 are biased rearward via the driven member 75 and are held in the rearmost position relative to the second intermediate shaft 42.

Although detailed illustration is omitted, when a load of a threshold value or more is applied to the second intermediate shaft 42 through the tool holder 32 (spindle 31) during rotation of the second intermediate shaft 42 due to the tip tool 91 being locked, the meshing engagement between the cam protrusion 752 and the cam recess 742 is released. More specifically, due to the action of the cam surfaces (inclined surfaces) of the cam protrusion 752 and the cam recess 742, the cam protrusion 752 disengages from the cam recess 742 and rides onto the front end surface of the driving side member 74 against the biasing force of the biasing spring 77. In other words, the driven side member 75 moves in a direction away from the driving side member 74 (forward). At this time, the driven side member 75 is guided by the ball 76 that rolls between the second intermediate shaft 42 and the driven side member 75, and can move smoothly forward. As a result, the torque transmission from the driving side member 74 to the driven side member 75 is interrupted, and the rotation of the second intermediate shaft 42 is interrupted.

As shown in Figures 3 and 4, the second transmission member 72 is disposed on the second intermediate shaft 42 and is configured to be rotatable integrally with the driving side member 74 of the torque limiter 73 and to be movable in the direction of the rotation axis A4 (front-rear direction) relative to the driving side member 74 and the gear member 423.

More specifically, the second transmission member 72 is a substantially cylindrical member arranged around the driving side member 74, and a first spline portion 721 and a second spline portion 722 are provided on the inner circumference of the second transmission member 72. The first spline portion 721 is provided in the front half of the second transmission member 72. The first spline portion 721 has a plurality of splines (internal teeth) that are always engaged with the spline portion 743 of the driving side member 74. The second spline portion 722 is provided at the rear end of the second transmission member 72. The second spline portion 722 has a plurality of splines (internal teeth) that can be engaged with the spline portion 425 of the gear member 423.

With this configuration, as shown by the solid line in FIG. 4, when the second spline portion 722 is disposed in a position where it engages with the spline portion 425 of the gear member 423 in the front-rear direction (hereinafter referred to as the engaged position), the second transmission member 72 can rotate integrally with the gear member 423. Therefore, the driving side member 74 spline-engaged with the second transmission member 72 can also rotate integrally with the gear member 423. In other words, when the second transmission member 72 is in the engaged position, it can transmit power from the gear member 423 to the second intermediate shaft 42 via the torque limiter 73. On the other hand, when the second spline portion 722 is disposed in a position (hereinafter referred to as the separated position) where it is separated from the spline portion 425 (where it cannot be engaged), as shown by the dotted line in FIG. 4, the second transmission member 72 disables (cuts off) the transmission of power from the gear member 423 to the second intermediate shaft 42.

As described above, in this embodiment, the second transmission member 72 and the gear member 423 function as a second clutch mechanism 71 that transmits or cuts off the power for drill operation. Note that in this embodiment, the second transmission member 72, like the first transmission member 64, is connected to the mode switching mechanism 80 (see FIG. 6) and is moved between an engaged position and a disengaged position in response to the operation of the mode switching dial 800 (see FIG. 2) by the user. In other words, like the first clutch mechanism 62, the second clutch mechanism 71 can also be switched between a power transmission state and a cut-off state in response to the operation of the mode switching dial 800.

The mode switching dial 800 and the mode switching mechanism 80 are described below.

As shown in Figures 6 to 8, the mode switching mechanism 80 is a mechanism configured to switch the operation mode of the hammer drill 101 in conjunction with the mode switching dial 800. In this embodiment, the hammer drill 101 has three operation modes: hammer drill mode, hammer mode, and drill mode. The hammer drill mode is an operation mode in which both the impact mechanism 6 and the rotation transmission mechanism 7 are driven to perform hammering and drilling operations. The hammer mode is an operation mode in which only the hammering operation is performed by cutting off the power transmission for the drilling operation by the second clutch mechanism 71 and driving only the impact mechanism 6. The drill mode is an operation mode in which only the drilling operation is performed by cutting off the power transmission for the hammering operation by the first clutch mechanism 62 and driving only the rotation transmission mechanism 7.

As shown in Figures 2, 4 and 6, the mode switching dial 800 is provided on the left side of the main body housing 10 (specifically, the drive mechanism housing 11) so that it can be operated externally by the user. The mode switching dial 800 includes a disk-shaped operating portion 801 having a knob, and a first pin 803 and a second pin 805 protruding from the operating portion 801.

The operating unit 801 is held by the main housing 10 so as to be rotatable around the rotation axis R (see FIG. 6). A part of the operating unit 801 is partially exposed to the outside from an opening formed in the left wall of the main housing 10 (drive mechanism housing 11), and can be rotated by the user. The mode switching dial 800 has rotation positions corresponding to the hammer drill mode, hammer mode, and drill mode. The user can set the operation mode by placing the mode switching dial 800 in a rotation position corresponding to the desired operation mode. The first pin 803 and the second pin 805 protrude from the inner surface of the operating unit 801 toward the inside of the main housing 10. The first pin 803 and the second pin 805 move on a circumference centered on the rotation axis R of the operating unit 801 as the mode switching dial 800 rotates.

The mode switching mechanism 80 includes a first switching member 81, a second switching member 82, a first spring 83, and a second spring 84.

The first switching member 81 has a pair of support holes (not shown) and is supported by a support shaft 88 inserted into the support holes so as to be movable in the front-rear direction. The support shaft 88 is supported by the main housing 10 (specifically, the support wall 113 fixed inside the drive mechanism accommodating section 11) and is a shaft extending in the front-rear direction. The support shaft 88 extends parallel to the first intermediate shaft 41 and the second intermediate shaft 42. A retaining ring 881 is fixed to the axial center of the support shaft 88. The first switching member 81 is supported in front of the retaining ring 881. The second switching member 82 has a pair of support holes (not shown) and is supported by the support shaft 88 inserted into the support holes so as to be movable in the front-rear direction behind the retaining ring 881.

The first switching member 81 and the second switching member 82 are engaged with the first transmission member 64 and the second transmission member 72, respectively. More specifically, the outer periphery of the first transmission member 64 and the second transmission member 72 is provided with annular grooves 645 and 725, respectively. The first switching member 81 is engaged with the first transmission member 64 via a plate-shaped first engagement portion 813 (see FIG. 8) arranged in the groove 645. Similarly, the second switching member 82 is engaged with the second transmission member 72 via a plate-shaped second engagement portion 823 (see FIG. 5) arranged in the groove 725. Note that the first transmission member 64 and the second transmission member 72 are rotatable with respect to the first switching member 81 and the second switching member 82 with the first engagement portion 813 and the second engagement portion 823 engaged with the grooves 645 and 725, respectively.

The first spring 83 is a compression coil spring, and is arranged in a compressed state between the drive mechanism housing 11 and the first switching member 81, and always urges the first switching member 81 backward. As a result, the first transmission member 64 engaged with the first switching member 81 is also always urged toward the rear engagement position. The second spring 84 is a compression coil spring, and is arranged in a compressed state between the stop ring 881 fixed to the support shaft 88 and the second switching member 82, and always urges the second switching member 82 backward. As a result, the second transmission member 72 engaged with the second switching member 82 is also always urged toward the rear engagement position. The rearmost position of the first switching member 81 is the position where the first switching member 81 abuts against the stop ring 881. The rearmost position of the second switching member 82 is the position where the second switching member 82 abuts against the front surface of the support wall 113.

When the mode switching dial 800 is located in a rotational position corresponding to the hammer drill mode shown in FIG. 6 (hereinafter referred to as the hammer drill position), the first pin 803 is located in a position adjacent to the rear of the first switching member 81 located in the rearmost position, and the second pin 805 is located in a position adjacent to the rear of the second switching member 82 located in the rearmost position. At this time, the first transmission member 64 is located in an engagement position where the second spline portion 642 engages with the spline portion 631 of the intervening member 63 (see FIG. 5), and the first clutch mechanism 62 is placed in a power transmission state. In addition, the second transmission member 72 is located in an engagement position where the second spline portion 722 engages with the spline portion 425 of the gear member 423 (see FIG. 4), and the second clutch mechanism 71 is also placed in a power transmission state.

When the motor 2 is energized, power is transmitted from the motor shaft 25 to the first intermediate shaft 41 via the drive bevel gear 255 and the driven bevel gear 414. Furthermore, power is transmitted from the first intermediate shaft 41 to the impact mechanism 6 via the first clutch mechanism 62, and a hammering operation is performed. At the same time, power is transmitted from the first intermediate shaft 41 to the drive gear 415 and the driven gear 424, and further to the second intermediate shaft 42 via the second clutch mechanism 71 and the torque limiter 73. Furthermore, power is transmitted from the second intermediate shaft 42 to the spindle 31 via the rotation transmission mechanism 7, and a drilling operation is also performed.

When the mode switching dial 800 is rotated from the hammer drill position shown in FIG. 6 to a rotation position corresponding to the hammer mode shown in FIG. 7 (hereinafter referred to as the hammer position), the second pin 805 moves in a clockwise direction while abutting the second switching member 82 from the rear, and moves the second switching member 82 forward against the biasing force of the second spring 84. When the mode switching dial 800 is located in the hammer position, the second switching member 82 is located in the frontmost position. As the second switching member 82 moves, the second transmission member 72 moves from the engaged position to the disengaged position (see FIG. 4), and the second clutch mechanism 71 is switched to the disconnected state.

Meanwhile, the first pin 803 moves in a clockwise direction in a bottom view without interfering with either the first switching member 81 or the second switching member 82, and is positioned away from the first switching member 81 and the second switching member 82. Therefore, during this time, the first switching member 81 and the first transmission member 64 do not move, and the first clutch mechanism 62 remains in the power transmission state.

Even when the motor 2 is energized, no power is transmitted from the motor shaft 25 to the second intermediate shaft 42, so no drilling action is performed. On the other hand, power is transmitted from the motor shaft 25 via the first intermediate shaft 41 to the impact mechanism 6, so only the hammering action is performed.

When the mode switching dial 800 is rotated from the hammer drill position shown in FIG. 6 to a rotation position corresponding to the drill mode shown in FIG. 8 (hereinafter referred to as the drill position), the first pin 803 abuts against the first switching member 81 from the rear and moves counterclockwise around the rotation axis R of the operating unit 801 in a bottom view, moving the first switching member 81 forward against the biasing force of the first spring 83. When the mode switching dial 800 is placed in the drill position, the first switching member 81 is placed in the frontmost position. As the first switching member 81 moves, the first transmission member 64 is moved from the engaged position to the disengaged position (see FIG. 5), and the first clutch mechanism 62 is switched to the disconnected state.

Meanwhile, the second pin 805 moves counterclockwise around the rotation axis R of the operating unit 801 in a bottom view without interfering with either the first switching member 81 or the second switching member 82, and is positioned adjacent to the second switching member 82. Therefore, during this time, the second switching member 82 and the second transmission member 72 do not move, and the second clutch mechanism 71 remains in the power transmission state.

Even when the motor 2 is energized, no power is transmitted from the first intermediate shaft 41 to the motion conversion member 61, so no hammering action is performed. On the other hand, power is transmitted from the motor shaft 25 via the second intermediate shaft 42 to the rotation transmission mechanism 7, so only the drilling action is performed.

As described above, in the hammer drill 101 of this embodiment, the spindle 31, the first intermediate shaft 41 for the striking mechanism 6 that performs the hammering operation, and the second intermediate shaft 42 for the rotation transmission mechanism that performs the drilling operation extend parallel to each other. On the other hand, the motor shaft 25 extends in a direction intersecting with the spindle 31. The rotation of the motor shaft 25 is first transmitted to the first intermediate shaft 41 via the driving bevel gear 255 and the driven bevel gear 414, and then transmitted to the second intermediate shaft 42 via the driving gear 415 and the driven gear 424. In other words, the spindle 31 is not interposed on the transmission path between the first intermediate shaft 41 and the second intermediate shaft 42. Therefore, unlike the case where the rotation is transmitted from the second intermediate shaft 42 to the first intermediate shaft 41 via the spindle 31, no deceleration or acceleration is required, and therefore efficient transmission can be performed.

The load caused by the hammering operation is greater than the load caused by the drilling operation. Therefore, in this embodiment, a configuration is adopted in which torque is transmitted directly from the motor shaft 25 to the first intermediate shaft 41, which receives the greater load out of the first intermediate shaft 41 and the second intermediate shaft 42.

In addition, on the first intermediate shaft 41, the driven bevel gear 414 is disposed adjacent to the front side of the bearing 412, and the drive gear 415 is disposed between the driven bevel gear 414 and the motion conversion member 61. In other words, the driven bevel gear 414 and the drive gear 415 are disposed close to the bearing 412 that supports the first intermediate shaft 41. This minimizes the area in which the driven bevel gear 414 and the drive gear 415 are disposed in the front-rear direction. In addition, by concentrating the various gears near the bearing 412, which has little deflection, the meshing between the drive bevel gear 255 and the driven bevel gear 414, and between the drive gear 415 and the driven gear 424 can be maintained with high precision.

In addition, the first intermediate shaft 41 requires a certain length since the motion conversion member 61 is mounted on it. In contrast, the drive gear 78 mounted on the second intermediate shaft 42 does not require such a length. In particular, in this embodiment, as described above, the arrangement of the driven gear 424 on the second intermediate shaft 42 is determined according to the drive gear 415 arranged near the rear bearing 412, so that the second intermediate shaft 42 has sufficient space in front of the driven gear 424. Therefore, the torque limiter 73 is arranged by making effective use of this space. The second intermediate shaft 42 has a lower transmission torque than the spindle 31 as the final output shaft. Therefore, a torque limiter 73 that is smaller and lighter than the torque limiter mounted on the spindle 31 can be adopted.

In addition, in the torque limiter 73 of this embodiment, when the torque limiter 73 is in operation, the balls 76 roll and guide the driven member 75 in the direction of the rotation axis A4. This reduces friction between the driven member 75 and the second intermediate shaft 42 and stabilizes the operating torque.

In this embodiment, the drive shaft A1, the rotation axis A2 of the motor shaft 25, and the rotation axis A3 of the first intermediate shaft 41 are all on the reference plane P, while the rotation axis A4 of the second intermediate shaft 42 is located to the left of the reference plane P. Therefore, the center of gravity of the hammer drill 101 is likely to be biased to the left of the reference plane P. However, since there are more right-handed users than left-handed users, it is thought that the bias in the center of gravity can be easily addressed by users attaching an auxiliary handle to the barrel portion 111 and holding it with their left hand. Therefore, it is reasonable to position the rotation axis A4 of the second intermediate shaft 42 on the left side of the reference plane P rather than on the right side.

In addition, in this embodiment, the first intermediate shaft 41 and the second intermediate shaft 42 are provided with a first clutch mechanism 62 and a second clutch mechanism 71, respectively. Therefore, it is possible to cut off the power for the hammer operation and the power for the drill operation, respectively, as necessary. Furthermore, both the first clutch mechanism 62 and the second clutch mechanism 71 can be switched between a power transmission state and a power cut-off state in response to the operation of the same operating member (mode switching dial 800). Therefore, the user can operate the first clutch mechanism 62 and the second clutch mechanism 71 simply by operating the mode switching dial 800 according to the desired work and switching the operation mode. In particular, in this embodiment, a rational arrangement of the mode switching dial 800 and the mode switching mechanism 80 is realized by utilizing the space generated below the second intermediate shaft 42.

The correspondence between each component of the above embodiment and each component of the present invention is shown below. However, each component of the embodiment is merely an example and does not limit each component of the present invention. The hammer drill 101 is an example of a "hammer drill". The spindle 31 is an example of a "final output shaft". The drive shaft A1 is an example of a "drive shaft". The motor 2 and the motor shaft 25 are examples of a "motor" and a "motor shaft", respectively. The first intermediate shaft 41 is an example of a "first intermediate shaft". The impact mechanism 6 is an example of a "first drive mechanism". The second intermediate shaft 42 is an example of a "second intermediate shaft". The rotation transmission mechanism 7 is an example of a "second drive mechanism". The drive bevel gear 255 and the driven bevel gear 414 are an example of a "pair of bevel gears". The drive gear 415 and the driven gear 424 are an example of a "pair of gears".

The motion conversion member 61 is an example of a "motion conversion member." The bearing 412 is an example of a "bearing." The driven bevel gear 414 is an example of "one of a pair of bevel gears." The drive gear 415 is an example of "one of a pair of gears." The torque limiter 43 is an example of a "torque limiter." The first clutch mechanism 62 and the second clutch mechanism 71 are examples of a "first clutch mechanism" and a "second clutch mechanism," respectively. The mode switching dial 800 (operation unit 801) is an example of an "operation member."

The above embodiment is merely an example, and the fastening tool according to the present invention is not limited to the configuration of the hammer drill 101 shown in the example. For example, the following modifications can be made. Note that any one or more of these modifications can be adopted in combination with the hammer drill 101 shown in the embodiment or the invention described in each claim.

The hammer drill 101 may be configured to operate on power supplied from an external AC power source instead of a rechargeable battery. In this case, a power cable that can be connected to an external AC power source is provided instead of the battery mounting section 173. In addition, the motor 2 may be an AC motor instead of a DC motor, and may be a motor with brushes instead of a brushless motor.

The configuration (shape, components, materials, etc.) of the main body housing 10 and the handle 15 may be changed as appropriate. For example, the motor housing 12 may protrude downward from the rear end of the drive mechanism housing 11 so as to be perpendicular to the drive axis A1. In this case, the motor 2 is positioned so that the rotation axis A2 of the motor shaft 25 is perpendicular to the rotation axis A3 of the first intermediate shaft 41.

The main housing 10 may also have a vibration-proof structure different from the vibration-proof structure exemplified in the above embodiment. For example, both ends of the handle 15 may be elastically connected to the main housing 10 so as to be movable relative to the main housing 10. Alternatively, the main housing 10 may include an inner housing that houses the drive mechanism 5, and an outer housing that includes a gripping portion that is held by the user and is elastically connected to the inner housing so as to be movable relative to the inner housing. Furthermore, inside the main housing 10, the spindle 31 and the impact mechanism 6 may be supported by a support body and may be movable in the front-rear direction integrally with the main housing 10. Such a vibration-proof structure is disclosed, for example, in JP 2016-000447 A.

The arrangement of the first intermediate shaft 41 (rotation axis A3) and the second intermediate shaft 42 (rotation axis A4) relative to the motor shaft 25 (rotation axis A2), and the arrangement of the first intermediate shaft 41 (rotation axis A3) and the second intermediate shaft 42 (rotation axis A4) relative to the spindle 31 (drive shaft A1) are not limited to the arrangements exemplified in the above embodiment.

For example, the rotation of the motor shaft 25 may first be transmitted to the second intermediate shaft 42 instead of the first intermediate shaft 41, and then further transmitted to the first intermediate shaft 41. In this case, it is preferable that a driven bevel gear that meshes with the drive bevel gear 255 is provided adjacent to the front side of the bearing 422 of the second intermediate shaft 42, and a drive gear is further provided adjacent to the front side of that. Then, a driven gear that meshes with the drive gear of the second intermediate shaft 42 may be provided adjacent to the front side of the bearing 412 of the first intermediate shaft 41.

The rotation axis A2 of the motor shaft 25 and the rotation axis A3 of the first intermediate shaft 41 (or the rotation axis A4 of the second intermediate shaft 42) do not have to be on the same plane. In this case, the rotation of the motor shaft 25 may be transmitted to the first intermediate shaft 41 (or the second intermediate shaft 42) via, for example, a hypoid gear. In addition, the drive shaft A1 does not have to be on the same plane as the rotation axis A2 of the motor shaft 25 and/or the rotation axis A3 of the first intermediate shaft 41.

The configurations and positions of the first clutch mechanism 62, the second clutch mechanism 71, the torque limiter 73, and the mode switching mechanism 80 may be changed as appropriate.

For example, the intervening member 63 may be omitted, and the first transmission member 64 of the first clutch mechanism 62 may be movable between a position where it engages with the motion conversion member 61 (specifically, the rotating body 611) and a position where it is separated from the motion conversion member 61. In other words, the first transmission member 64 may be configured to directly transmit the rotation of the first intermediate shaft 41 to the motion conversion member 61. In addition, the second clutch mechanism 71 may be configured to transmit or cut off power between the second intermediate shaft 42 and the drive gear 78, rather than between the driven gear 424 and the second intermediate shaft 42.

Of the three operating modes, hammer drill mode, hammer mode, and drill mode, the hammer drill 101 may have only the hammer drill mode and the hammer mode. In this case, only the second clutch mechanism 71 is provided on the second intermediate shaft 42, and the first clutch mechanism 62 is omitted. In this case, the first switching member 81 and the first spring 83 of the mode switching mechanism 80 are also omitted.

The driven member 75 of the torque limiter 73 and the second intermediate shaft 42 may be engaged, for example, by splines, rather than via balls 76. The driving member 74 may be movable on the second intermediate shaft 42, instead of the driven member 75. The torque limiter 73 may be omitted, or may be provided on the spindle 31.

In the mode switching mechanism 80, the shapes, arrangements, and interlocking manner with the mode switching dial 800 of the first switching member 81, the second switching member 82, the first spring 83, and the second spring 84 may be appropriately changed. For example, the first switching member 81 for switching the first clutch mechanism 62 and the second switching member 82 for switching the second clutch mechanism 71 may be configured to be moved by separate operating members. In addition, the operating member interlocking with the mode switching mechanism 80 is not limited to a rotating dial, and may be, for example, a sliding lever. The first spring 83 and the second spring 84 may be other types of springs (for example, tension coil springs, torsion springs), and the first switching member 81 and the second switching member 82 do not necessarily have to be biased.

Furthermore, in consideration of the spirit of the present invention and the above-described embodiment, the following aspects are constructed. The following aspects can be adopted in combination with the hammer drill 101 shown in the embodiment and the above-described modified examples, or the invention described in each claim.
[Aspect 1]
The rotation axis of the motor shaft and the rotation axis of the first intermediate shaft are on the same plane.
[Aspect 2]
The rotation axis of the second intermediate shaft is disposed on the left side of the drive shaft.
[Aspect 3]
The first drive mechanism includes:
a swinging member disposed on the first intermediate shaft and configured to swing in association with rotation of the first intermediate shaft;
a piston configured to reciprocate along the drive shaft in association with the swing of the swing member;
and an impactor configured to move linearly by the action of an air spring caused by the reciprocating motion of the piston to drive the tool bit linearly.
The motion conversion member 61 (oscillating member 616), the piston 65, and the striker 67 are examples of the "oscillating member", the "piston", and the "striker" in this embodiment, respectively.
[Aspect 4]
The second drive mechanism is
a first rotation transmission gear disposed on the second intermediate shaft and configured to rotate together with the second intermediate shaft;
The reduction gear mechanism includes a second rotation transmission gear that is provided on the outer periphery of the spindle and meshes with the first rotation transmission gear.
The drive gear 78 and the driven gear 79 are examples of the "first rotation transmission gear" and the "second rotation transmission gear", respectively, in this embodiment.
[Aspect 5]
The torque limiter is
A driving cam;
a driven cam engageable with the drive cam;
a ball rollably disposed in a raceway extending in the axial direction of the second intermediate shaft between an inner periphery of one of the driving cam and the driven cam and an outer periphery of the second intermediate shaft,
the one of the driving side cam and the driven side cam is configured to disengage from the other of the driving side cam and the driven side cam by being guided by the ball in the axial direction in a direction away from the other of the driving side cam and the driven side cam when a torque acting on the second intermediate shaft exceeds a threshold value.
The driving side member 74, the driven side member 75, and the ball 76 are examples of the "driving side cam", the "driven side cam", and the "ball" in this embodiment, respectively.
[Aspect 6]
The torque limiter includes a biasing member that biases one of the driving cam and the driven cam toward the other.
The biasing spring 77 is an example of the "biasing member" in this embodiment.
[Aspect 7]
A switching mechanism configured to switch the operation mode in conjunction with the operation member,
The switching mechanism includes:
a first switching member configured to move in response to the manual operation of the operating member and to switch the first clutch mechanism between the power transmission state and the disconnected state;
The second switching member is configured to move in response to the manual operation and to switch the second clutch mechanism between the power transmission state and the disconnected state.
The mode switching mechanism 80, the first switching member 81, and the second switching member 82 are examples of the "switching mechanism", the "first switching member", and the "second switching member" in this embodiment, respectively.
[Aspect 8]
The operating member has a first abutment portion configured to abut against the first switching member and move the first switching member, and a second abutment portion configured to abut against the second switching member and move the second switching member.
The first pin 803 and the second pin 805 are examples of the "first contact portion" and the "second contact portion" in this embodiment, respectively.
[Aspect 9]
The first switching member and the second switching member are movably supported by a single support member.
The support shaft 88 is an example of the "support member" in this embodiment.

1: Hammer drill, 2: Motor, 5: Drive mechanism, 6: Impact mechanism, 7: Rotation transmission mechanism, 10: Main body housing, 11: Drive mechanism accommodating section, 12: Motor accommodating section, 15: Handle, 16: Grip section, 17: Controller accommodating section, 20: Main body, 25: Motor shaft, 31: Spindle, 32: Tool holder, 33: Cylinder, 41: First intermediate shaft, 42: Second intermediate shaft, 43: Torque limiter, 61: Motion conversion member, 62: First clutch mechanism, 63: Intermediate current member, 64: first transmission member, 65: piston, 67: striker, 68: impact bolt, 71: second clutch mechanism, 72: second transmission member, 73: torque limiter, 74: driving side member, 75: driven side member, 76: ball, 77: biasing spring, 78: driving gear, 79: driven gear, 80: mode switching mechanism, 81: first switching member, 82: second switching member, 83: first spring, 84: second spring, 88: support shaft, 91: tip tool, 101: hammer drill, 111: bar rail portion, 113: support wall, 161: trigger, 162: switch, 171: controller, 173: battery mounting portion, 251: bearing, 255: driving bevel gear, 316: bearing, 411: bearing, 412: bearing, 414: driven bevel gear, 415: driving gear, 416: spline portion, 421: bearing, 422: bearing, 423: gear member, 424: driven gear, 425: spline portion, 611: rotating body, 614: bearing, 616: swing member, 617: arm portion, 631: spline Line part, 641: first spline part, 642: second spline part, 645: groove, 721: first spline part, 722: second spline part, 725: groove, 742: cam recess, 743: spline part, 752: cam protrusion, 800: mode switching dial, 801: operation part, 803: first pin, 805: second pin, 813: first engagement part, 823: second engagement part, 881: retaining ring, A1: drive shaft, A2: rotating shaft, A3: rotating shaft, A4: rotating shaft, P: reference surface, R: rotating shaft

Claims (9)

A hammer drill,
a final output shaft configured to removably hold the tool bit and rotatably disposed about the drive axis;
a motor having a motor shaft extending in a direction intersecting the drive shaft;
a first intermediate shaft extending parallel to the drive shaft;
a first drive mechanism configured to convert a rotational motion of the first intermediate shaft into a linear motion and to perform a hammering action of linearly driving the tool bit along the drive shaft;
a second intermediate shaft extending parallel to the drive shaft;
a second drive mechanism configured to transmit rotation of the second intermediate shaft to the final output shaft and to perform a drilling operation of rotating the bit about the drive shaft,
the motor shaft is configured to rotate the first intermediate shaft via a drive bevel gear provided on the motor shaft and a driven bevel gear provided on the first intermediate shaft and meshing with the drive bevel gear,
the first intermediate shaft is configured to rotate the second intermediate shaft via a drive gear provided on the first intermediate shaft and a driven gear provided on the second intermediate shaft and meshing with the drive gear,
the first drive mechanism includes a motion conversion member disposed on the first intermediate shaft and configured to convert a rotational motion of the first intermediate shaft into a linear motion;
When the extending direction of the drive shaft is defined as the front-rear direction of the hammer drill, and the side to which the bit is attached in the front-rear direction is defined as the front side,
the driven bevel gear of the first intermediate shaft is disposed adjacent to a front side of a first bearing that rotatably supports a rear end portion of the first intermediate shaft,
The hammer drill, wherein the drive gear of the first intermediate shaft is disposed between the driven bevel gear and the motion conversion member in the front-rear direction. 2. The hammer drill according to claim 1,
In the front-rear direction, the driven bevel gear of the first intermediate shaft is located in front of the drive bevel gear of the motor shaft,
The hammer drill, wherein the drive gear of the first intermediate shaft is disposed adjacent to a front side of the driven bevel gear. 3. The hammer drill according to claim 1 or 2,
the first bearing, which rotatably supports the rear end of the first intermediate shaft, and the second bearing, which rotatably supports the rear end of the second intermediate shaft, are supported by a common support wall. A hammer drill according to any one of claims 1 to 3,
The hammer drill further comprises a torque limiter disposed on the second intermediate shaft and configured to cut off transmission of torque acting on the second intermediate shaft when the torque exceeds a threshold value. A hammer drill according to any one of claims 1 to 4,
The hammer drill, wherein a rotation axis of the motor shaft and a rotation axis of one of the first intermediate shaft and the second intermediate shaft are on the same plane. 6. The hammer drill according to claim 5,
The hammer drill is characterized in that the drive shaft is also on the same plane. 7. The hammer drill according to claim 6,
A direction perpendicular to the drive shaft and corresponding to an extension direction of the motor shaft is defined as an up-down direction, and a direction perpendicular to the front-rear direction and the up-down direction is defined as a left-right direction,
Furthermore, in the vertical direction, when the side on which the motor is disposed with respect to the drive shaft is defined as the lower side,
The hammer drill , wherein a rotation axis of the other of the first intermediate shaft and the second intermediate shaft is disposed on the left side of the plane when facing forward. A hammer drill according to any one of claims 1 to 7,
a first clutch mechanism provided on the first intermediate shaft and configured to transmit or interrupt power for the hammer operation;
a second clutch mechanism provided on the second intermediate shaft and configured to transmit or interrupt power for operating the drill. 9. The hammer drill according to claim 8,
The hammer drill further includes an operating member for switching the operation mode of the hammer drill, the operating member being configured to be manually operated by a user,
The hammer drill, characterized in that the first clutch mechanism and the second clutch mechanism are both configured to be switched between a power transmission state and a power cut-off state in response to operation of the operating member.

Images