JP6939137B2 - Power work machine - Google Patents

Description

The present invention relates to a power working machine.

Conventionally, power work such as forming a hole in a work material (for example, concrete, steel, wood, etc.) by rotating the tip tool by driving a motor, or crushing by applying a striking force to the tip tool. The machine is widely known. As an example of such a power work machine, as an operation mode, a rotation / striking mode in which the tip tool is rotated while applying a striking force to the tip tool, a rotation mode in which the tip tool is only rotated, and a striking force are applied to the tip tool. A hammer drill that can switch to a single striking mode is known (see Patent Document 1).

In such a power work machine, the tip tool may get caught in a hard part of the work material during work and the tip tool may lock, causing kickback in which the housing is largely swung by the drive of the tip tool, resulting in workability. It could get worse.

In order to deal with the kickback, a power work machine in which an acceleration sensor is provided in the housing can be considered. In the power work machine, when the housing is swung widely and acceleration in the driving direction of the tip tool is generated in the housing, the acceleration sensor detects the acceleration and controls to stop the rotation of the motor. Further, in general, the handle gripped by the operator has less vibration in the axial direction of the tip tool than the gear housing in which the striking mechanism is housed. Therefore, an acceleration sensor is provided in the handle in order to appropriately detect the acceleration of the housing in the rotation direction of the tip tool.

Japanese Unexamined Patent Publication No. 2017-13173

In the above configuration, in order to appropriately detect the acceleration of the housing in the rotation direction of the tip tool, it is advantageous that the distance between the acceleration sensor and the axis of the tip tool is long. On the other hand, as described above, since it is necessary to provide the acceleration sensor in the handle, the acceleration sensor has to be arranged at a position close to the axis of the tip tool depending on the shape of the handle.

Therefore, an object of the present invention is to increase the degree of freedom in arranging the acceleration sensor and to provide a power work machine capable of appropriately detecting the acceleration in the rotation direction of the tip tool generated in the housing.

In order to solve the above problems, the present invention comprises a housing, a motor housed in the housing and having a rotating shaft, an output unit driven by the motor and to which a tip tool can be attached and detached, and a rotational movement of the rotating shaft. A power transmission unit capable of transmitting and driving the tip tool and a sensor unit supported by the housing and capable of detecting the motion state of the housing are provided, and the sensor unit is the first of the sensor units. The power work machine is supported by the housing so that the movement allowance for the housing in one direction is larger than the movement allowance for the housing in the second direction intersecting the first direction of the sensor unit. Is provided.

According to the power working machine having the above configuration, the allowable movement amount of the sensor unit with respect to the housing in the direction intersecting the driving direction of the tip tool is smaller than the movable allowable amount of the sensor unit in the driving direction (front-back direction) of the tip tool. Therefore, it is possible to appropriately detect the acceleration of the housing in the direction intersecting the driving direction of the tip tool while suppressing the detection of the vibration in the driving direction of the tip tool.

In the above configuration, the power transmission unit can transmit the rotation direction of the rotation shaft to rotate the tip tool in the rotation direction about an axis extending in the first direction, and the rotational movement of the rotation shaft. Can be reciprocated to reciprocate the tip tool in the first direction, and the second direction is preferably the rotation direction.

According to such a configuration, it is possible to appropriately detect the acceleration of the housing in the rotation direction of the tip tool while suppressing the detection of the vibration in the reciprocating direction of the tip tool.

In the above configuration, it is preferable that the sensor unit is supported by the housing via a cushioning member.

According to such a configuration, by providing the cushioning member in the first direction, it is possible to easily suppress the axial vibration of the tip tool from being transmitted to the acceleration sensor. Further, it is not necessary to provide the sensor unit on the handle, the degree of freedom in arranging the sensor unit is increased, and the sensor unit can be arranged at a position far from the axis of the tip tool.

It is preferable that the sensor unit is directly supported by the housing in the rotation direction.

According to such a configuration, since the sensor unit is directly supported by the housing, it is possible to appropriately detect the acceleration in the rotational direction of the housing.

Further, the housing has a sensor portion support portion that supports the sensor portion, the sensor portion support portion has a support member having a spring constant larger than that of the cushioning member, and the sensor portion has the rotation. In the direction, it is preferably supported by the support member.

According to such a configuration, since the housing has a support member having a spring constant larger than that of the cushioning member, it is possible to appropriately detect the acceleration in the rotational direction of the housing.

Further, the output unit has a tip tool mounting portion to which the tip tool can be attached and detached, and the housing has a gear housing accommodating the power transmission portion and a side opposite to the tip tool mounting portion with respect to the gear housing. A handle portion located in and gripped by an operator is further provided, and the distance between the sensor portion and the axis line is longer than the distance between the end portion of the handle portion farthest from the axis line and the axis line. Is preferable.

According to such a configuration, since the sensor portion is located below the lower end portion of the handle portion, it is possible to appropriately detect the acceleration in the rotational direction of the tip tool generated in the housing.

Further, a battery pack for supplying electric power to the motor is further provided, and the distance between the battery pack and the axis is longer than the distance between the end of the handle portion farthest from the axis and the axis, and the sensor. It is preferable that the portion is provided at a position where the position in the third direction perpendicular to the first direction overlaps with the battery pack.

According to such a configuration, the sensor portion is located at a position overlapping the battery pack located below the lower end portion of the handle portion in the vertical or horizontal direction of the power work machine, so that the tip tool appropriately generated in the housing It becomes possible to detect the acceleration in the rotation direction.

It is preferable that the rotation axis extends in a third direction perpendicular to the first direction, and the sensor unit is provided at a position where the position in the third direction overlaps with the motor.

The present invention further comprises a housing, a motor housed in the housing and having a rotating shaft, an output unit driven by the motor to which the tip tool can be attached and detached, and the tip tool by transmitting the rotational motion of the rotating shaft. A power transmission unit that can be driven in the front-rear direction, a battery pack that supplies power to the motor, a sensor unit that is supported by the housing and can detect the motion state of the housing, and the housing and the sensor unit. The housing comprises a grip portion extending in the vertical direction and a handle portion located behind the motor, the battery pack is located below the handle portion. is arranged, said sensor unit is configured with the position in the vertical direction is arranged in front of the front Symbol battery pack so as to overlap with the battery pack, the rear of the axis of the rotary shaft of position in the longitudinal direction the motor Further, the present invention provides a power working machine characterized in that it is arranged between the battery pack and the axis.
In the above configuration, the cushioning member preferably includes a plurality of elastic bodies supported by the housing so as to sandwich the sensor portion.
Further, the cushioning member is arranged between a first elastic body arranged between the housing and the sensor portion in the front-rear direction and a second elastic body arranged between the housing and the sensor portion in the vertical direction . It is preferable to include an elastic body of.
Further, the housing has a wall surface facing the battery pack in the front-rear direction, and the sensor portion has a flat plate shape and is arranged so as to extend in the vertical direction and the horizontal direction along the wall surface. preferable.
Further, the motor is a brushless motor and further has a control unit that controls the drive of the motor, and the control unit is separated from the sensor unit and electrically connected to the sensor unit via a conducting wire. It is preferable that the control unit is arranged so that the position in the vertical direction overlaps with the motor, and the sensor unit is arranged below the control unit.
Further, the housing further includes a motor housing that is connected to the handle portion and houses the motor inside, and the handle portion extends forward from the lower end portion of the grip portion and extends in the left-right direction. The first connection portion rotatably connected to the motor housing with the moving shaft as a fulcrum, and the motor housing extending forward from the upper end portion of the grip portion and via a vibration reduction mechanism. It is preferable that the sensor unit and the control unit are supported by the motor housing so as to have a substantially U-shape in the left-right direction including the second connection portion connected to the motor housing.
Further, the handle portion has a laterally defined U-shape including a first connecting portion extending forward from the lower end portion of the grip portion and a second connecting portion extending forward from the upper end portion of the grip portion. It has a shape, and the sensor unit is preferably arranged below the first connection unit.
The present invention further comprises a housing, a motor housed in the housing and having a rotating shaft, an output unit driven by the motor and to which the tip tool can be attached and detached, and the tip tool by transmitting the rotational motion of the rotating shaft. A power transmission unit that can be driven in the front-rear direction, a battery pack that supplies electric power to the motor, a sensor unit that is supported by the housing and can detect the motion state of the housing, and the housing and the sensor unit. The housing includes a grip portion extending in the vertical direction and a handle portion located behind the motor, the battery pack is located below the handle portion. The sensor unit is arranged in front of the battery pack so that the position in the vertical direction overlaps with the battery pack, and the sensor unit is a movement allowance of the sensor unit with respect to the housing in the front-rear direction. However, there is provided a power working machine characterized in that it is supported by the housing so as to be larger than the movement allowance for the housing in the left-right direction of the sensor unit.
Further, the power transmission unit can transmit the rotational motion of the rotary shaft to rotate the tip tool in the rotational direction around the axis extending in the front-rear direction, and reciprocate the rotary motion of the rotary shaft. It is possible to reciprocate the tip tool in the front-rear direction, and it is preferable that the axis line is arranged above the motor.
Further, it is preferable that the sensor unit is supported by the housing in the front-rear direction via a cushioning member.
Further, it is preferable that the sensor unit is directly supported by the housing in the left-right direction.
Further, the housing has a sensor portion support portion that supports the sensor portion, the sensor portion support portion has a support member having a spring constant larger than that of the cushioning member, and the sensor portion has the left and right sides. In the direction, it is preferably supported by the support member.
The present invention further comprises a housing, a motor housed in the housing and having a rotating shaft, an output unit driven by the motor to which the tip tool can be attached and detached, and the tip tool by transmitting the rotational movement of the rotating shaft. A power transmission unit that can be driven in the front-rear direction, a battery pack that supplies power to the motor, a sensor unit that is supported by the housing and can detect the motion state of the housing, and the housing and the sensor unit. The housing has a grip portion extending in the vertical direction and is connected to a handle portion located behind the motor, and is connected to the handle portion and has the motor inside. The handle portion extends forward from the lower end portion of the grip portion and rotatably with respect to the motor housing with a rotation shaft extending in the left-right direction as a fulcrum. A substantially U-shape in the left-right direction including a first connection portion to be connected and a second connection portion extending forward from the upper end portion of the grip portion and connected to the motor housing via a vibration reduction mechanism. The power working machine is characterized in that the handle portion has an extension portion arranged in front of the battery pack, and the sensor portion is provided on the extension portion of the handle portion. Is provided .
Also, the battery pack is disposed below the handle portion, the sensor unit, so that the position in the vertical direction overlap with the battery pack, it is preferably arranged in front of the battery pack.
The present invention further comprises a housing, a motor housed in the housing and having a rotating shaft, an output unit driven by the motor and to which a tip tool can be attached and detached, and the tip tool by transmitting the rotational motion of the rotating shaft. A power transmission unit that can be driven in the front-rear direction, a battery pack that supplies power to the motor, a sensor unit that is supported by the housing and can detect the motion state of the housing, and the housing and the sensor unit. The housing comprises a grip portion extending in the vertical direction and a handle portion located behind the motor, the battery pack is located below the handle portion. The sensor unit is arranged in front of the battery pack so that the position in the vertical direction overlaps with the battery pack, and the housing has a wall surface facing the battery pack in the front-rear direction. The sensor unit provides a power working machine having a flat plate shape and being arranged so as to extend in the vertical direction and the horizontal direction along the wall surface.

According to the power working machine of the present invention, the degree of freedom in arranging the acceleration sensor is increased, and the acceleration in the rotation direction of the tip tool generated in the housing can be appropriately detected.

It is a figure which shows the internal structure of the hammer drill which concerns on 1st Embodiment of this invention. FIG. 1 is a partially enlarged cross-sectional view of FIG. 1, showing an embodiment in which the accelerometer support portion of the hammer drill according to the first embodiment of the present invention supports the accelerometer. FIG. 2 is a cross-sectional view taken along the line III-III of FIG. 2, showing an embodiment in which the accelerometer support portion of the hammer drill according to the first embodiment of the present invention supports the accelerometer. FIG. 1 is a view taken along the line IV-IV of FIG. 1, showing an embodiment in which the accelerometer support portion of the hammer drill according to the first embodiment of the present invention supports the accelerometer. It is a figure which shows the internal structure of the hammer drill which concerns on the 2nd Embodiment of this invention. FIG. 5 is a partially enlarged cross-sectional view of the VI of FIG. 5, showing an embodiment in which the accelerometer support portion of the hammer drill according to the second embodiment of the present invention supports the accelerometer.

The hammer drill 1 which is an example of the power working machine according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 4. The hammer drill 1 is an electric power working machine for forming a perforated hole in a work material (for example, concrete, steel, wood, etc.) or crushing it by applying a striking force. The hammer drill 1 has two operation modes: a "rotation / striking mode" in which the tip tool P rotates to pierce the work material and reciprocates to hit the work material, and the tip tool P rotates to the work material. It has a "rotation mode" for drilling and a "striking mode" in which the tip tool P reciprocates to hit the work piece. The tip tool P is an example of the "tip tool" in the present invention.

In the following description, "up" shown in FIG. 1 is defined as an upward direction, "down" is defined as a downward direction, "front" is defined as a forward direction, and "rear" is defined as a backward direction. Further, when the hammer drill 1 is viewed from the rear, "right" is defined as the right direction, and "left" is defined as the left direction. When the dimensions, numerical values, etc. are referred to in the present specification, not only the dimensions and numerical values that completely match the dimensions, numerical values, etc., but also the dimensions, numerical values, etc. that substantially match (for example, when it is within the range of manufacturing error). ) Shall be included. Similarly for "identical", "orthogonal", "parallel", "match", "plane", etc., "substantially identical", "substantially orthogonal", "substantially parallel", "substantially match", "substantially flush", etc. Etc. shall be included.

As shown in FIG. 1, the hammer drill 1 includes a housing 2, a motor 3, an inverter circuit board unit 4, a control unit 5, a power transmission unit 6, an output unit 7, and an acceleration sensor 8. Mainly has.

As shown in FIG. 1, the housing 2 includes a motor housing 21, a gear housing 22, a back cover 23, a handle housing 24, and an acceleration sensor support portion 25.

As shown in FIG. 1, the motor housing 21 has a cylindrical shape extending in the vertical direction, and houses the motor 3 and the inverter circuit board portion 4. The motor housing 21 has a rear wall portion 21A.

The rear wall portion 21A forms the rear portion of the motor housing 21 and extends in the vertical direction. An acceleration sensor support portion 25 for supporting the acceleration sensor 8 is provided below the rear wall portion 21A. The details of the acceleration sensor support portion 25 will be described later.

The motor 3 is a DC brushless motor and has a rotating shaft 31, a rotor 32, a stator 33, and a fan 34.

The rotating shaft 31 extends in the vertical direction and is rotatably supported by the housing 2. A pinion 31A that rotates integrally with the rotating shaft 31 is fixed to the upper end of the rotating shaft 31. The vertical direction is an example of the "third direction" in the present invention.

The rotor 32 is a rotor having a permanent magnet (not shown), and is provided on the rotating shaft 31 so as to be integrally rotatable with the rotating shaft 31.

The stator 33 is a stator having a stator winding (not shown). The stator 33 is fixed to the inner peripheral surface of the motor housing 21.

The fan 34 is fixed to the rotating shaft 31 so as to be integrally rotatable with the rotating shaft 31 below the pinion 31A.

The inverter circuit board portion 4 is provided above the stator 33 of the motor 3. The inverter circuit board unit 4 has a board 40. The substrate 40 has an inverter circuit (not shown) for supplying electric power of the battery pack Q to the motor 3 and controlling the rotation of the motor 3, and a magnetic sensor (not shown) for detecting the rotation position of the rotor 32. ) Etc. are implemented.

The gear housing 22 is made of metal, is connected to the upper part of the motor housing 21, and extends in the front-rear direction. The gear housing 22 houses a power transmission unit 6 and an output unit 7 inside. Further, a side handle 2A gripped by an operator is attached to the gear housing 22. The gear housing 22 is an example of the “gear housing” in the present invention.

The power transmission unit 6 has a power conversion mechanism 61 and a rotational force transmission mechanism 62, and can convert the rotation of the rotation shaft 31 of the motor 3 into reciprocating motion and transmit it to the output unit 7, and the motor 3 The rotation of the rotating shaft 31 can be transmitted to the output unit 7. The power transmission unit 6 is an example of the "power transmission unit" in the present invention.

The output unit 7 is arranged above the rotational force transmission mechanism 62 in the gear housing 22. The output unit 7 has a hammer 71, a cylinder 72, and a tool holding unit 73 to which the tip tool P can be attached and detached. The output unit 7 is an example of the “output unit” in the present invention. The tool holding portion 73 is an example of the “tip tool mounting portion” in the present invention.

The striking element 71 is configured to be reciprocating by a power conversion mechanism 61. The front end of the hammer 71 is configured to be able to come into contact with the rear end of the tip tool P mounted on the tool holding portion 73, and as the hammer 71 reciprocates in the front-rear direction, the tip tool P moves in the front-rear direction. It can move back and forth. The front-back direction is an example of the "first direction" in the present invention.

The cylinder 72 is configured to be rotatable about an axis A extending in the front-rear direction by receiving the rotational force of the motor 3 via the rotational force transmission mechanism 62. Further, the tool holding portion 73 is rotated by the rotation of the cylinder 72, and the tip tool P mounted on the tool holding portion 73 is configured to be rotatable around the axis A. In the following description, the direction in which the tip tool P rotates about the axis A is referred to as the rotation direction. Axis A is an example of the "axis" in the present invention. The direction of rotation is an example of the "second direction" in the present invention.

The back cover 23 extends in the vertical direction and is arranged so as to cover the rear portions of the motor housing 21 and the gear housing 22. The back cover 23 is provided with an insertion portion 23A and a connection portion 23B.

The insertion portion 23A projects rearward below the back cover 23. A through hole penetrating in the left-right direction is formed in the insertion portion 23A.

The connecting portion 23B extends in the front-rear direction at the upper end portion of the back cover 23.

Further, the control unit 5 is fixed in the back cover 23. The control unit 5 is configured to perform various controls on the hammer drill 1. The control unit 5 has a flat plate-shaped substrate (not shown), and various circuits and the like for controlling the hammer drill 1 are mounted on the substrate. The control unit 5 is electrically connected to the acceleration sensor 8 via the lead wire 8A.

The handle housing 24 has a substantially U-shape in side view and is located behind the back cover 23. As shown in FIG. 1, the handle housing 24 has a grip portion 24C, a first connection portion 24D, a second connection portion 24E, and an extension portion 24G.

The grip portion 24C is a portion gripped by an operator during work and extends in the vertical direction. The grip portion 24C is located on the opposite side of the gear housing 22 from the tool holding portion 73. A manually operable trigger 24A for controlling the start and stop of the motor 3 is provided on the upper part of the front portion of the grip portion 24C. The grip portion 24C is an example of the "handle portion" in the present invention.

The first connecting portion 24D extends forward from the lower end portion of the grip portion 24C. A shaft 24F extending in the left-right direction is provided inside the front portion of the first connecting portion 24D. The shaft 24F is inserted into the through hole of the insertion portion 23A. The handle housing 24 is configured to be rotatable around the shaft 24F as a fulcrum. Further, a battery mounting portion 24B to which the battery pack Q can be mounted is provided below the first connecting portion 24D. It is configured to be driveable by power supply from the battery pack Q mounted on the battery mounting portion 24B. The battery pack Q is an example of the "battery pack" in the present invention. Further, the extending portion 24G extends downward from the front end portion of the first connecting portion 24D.

The second connecting portion 24E extends forward from the upper end portion of the grip portion 24C. The second connection portion 24E is provided with a vibration reduction mechanism 2B, and the second connection portion 24E is connected to the connection portion 23B of the back cover 23 via the vibration reduction mechanism 2B. The vibration reduction mechanism 2B includes an elastic body (not shown). Even when vibration in the axis A direction occurs in the output unit 7, the handle housing 24 rotates around the shaft 24F, and the elastic body (not shown) of the vibration reduction mechanism 2B expands and contracts, so that the vibration in the axis A direction vibrates. Is absorbed, and the vibration in the axis A direction is reduced from being transmitted to the operator who grips the grip portion 24C.

Next, the configuration of the acceleration sensor support portion 25 that supports the acceleration sensor 8, the elastic body 9, and the acceleration sensor 8 will be described in detail with reference to FIGS. 1 to 4. FIG. 2 is a partially enlarged cross-sectional view of FIG. 1 II, FIG. 3 is a sectional view taken along line III-III of FIG. 2, and FIG. 4 is an arrow view of IV-IV of FIG.

As shown in FIG. 1, the acceleration sensor support portion 25 is located below the rear wall portion 21A of the motor housing 21. As shown in FIG. 2, the acceleration sensor support portion 25 has an accommodating wall portion 251 and a pressing portion 252. Further, as shown in FIGS. 3 and 4, the acceleration sensor support portion 25 is symmetrically configured. The acceleration sensor support unit 25 is an example of the “sensor unit support unit” in the present invention.

The accommodation wall portion 251 has a front wall 251A shown in FIG. 2, a lower wall 251B shown in FIG. 3, an upper left wall 251C, an upper right wall 251D, a left side wall 251E, and a right side wall 251F.

As shown in FIG. 2, the front wall 251A is formed in a flat plate shape that protrudes from the rear surface of the rear wall portion 21A and extends in the vertical and horizontal directions.

As shown in FIGS. 2 and 3, the lower wall 251B extends rearward from the lower end of the front wall 251A. The lower wall 251B has a flat plate shape extending in the front-rear direction and the left-right direction.

As shown in FIG. 3, the left side wall 251E and the right side wall 251F extend upward from the left end portion and the right end portion of the lower wall 251B, respectively. Although not shown in the figure, the front end of the left wall 251E is connected to the left end of the front wall 251A, and the front end of the right wall 251F is connected to the right end of the front wall 251A. The left side wall 251E and the right side wall 251F have a flat plate shape extending in the vertical direction and the front-rear direction.

As shown in FIG. 3, the upper left wall 251C and the upper right wall 251D are located at substantially the same position in the vertical direction. The upper left wall 251C extends to the right from the upper end of the left wall 251E, and the upper right wall 251D extends to the left from the upper end of the right wall 251F. As shown in FIG. 2, the front end of the upper left wall 251C is connected to the upper end of the front wall 251A, and although not shown in the figure, the front end of the right wall 251F is connected to the upper end of the front wall 251A. There is. The upper left wall 251C and the upper right wall 251D have a flat plate shape extending in the front-rear direction and the left-right direction. Further, an opening is formed by the right end surface of the upper left wall 251C and the left end surface of the upper right wall 251D.

The front wall 251A is integrally formed with the rear wall portion 21A of the motor housing 21. Further, the lower wall 251B, the upper left wall 251C, the upper right wall 251D, the left side wall 251E and the right side wall 251F are integrally formed with the front wall 251A. That is, the accommodating wall portion 251 is formed integrally with the motor housing 21, and is configured to be relatively immovable with respect to the motor housing 21.

The rear surfaces of the lower wall 251B, the upper left wall 251C, the upper right wall 251D, the left side wall 251E, and the right side wall 251F are flush with each other.

As shown in FIGS. 2 and 4, the pressing portion 252 has a screw 252A, a washer 252B, and a pressing plate 252C.

As shown in FIG. 4, the holding plate 252C has a flat plate shape extending in the left-right direction. Although not shown in the figure, a through hole is formed symmetrically in the holding plate 252C, and a screw 252A is inserted into the through hole via a washer 252B.

As shown in FIG. 2, the elastic body 9 is arranged in the accommodating wall portion 251. The spring constant of the elastic body 9 is smaller than that of the left side wall 251E and the right side wall 251F of the accommodating wall portion 251. The elastic body 9 has a first elastic body 9A, a second elastic body 9B, and a third elastic body 9C. The elastic body 9 is an example of the "buffer member" in the present invention.

The first elastic body 9A and the second elastic body 9B are elastic bodies made of resin, and have a flat plate shape extending in the front-rear direction and the up-down direction and having a thickness in the front-rear direction.

The third elastic body 9C is an elastic body made of resin, and has a flat plate shape extending in the front-rear direction and the left-right direction and having a thickness in the up-down direction.

The acceleration sensor 8 is arranged in the accommodating wall portion 251 of the acceleration sensor support portion 25. In the present embodiment, an acceleration signal corresponding to the acceleration in the rotation direction of the housing 2 can be detected. As shown in FIG. 1, the acceleration sensor 8 is electrically connected to the control unit 5 via a conducting wire 8A, and outputs an acceleration signal corresponding to the acceleration in the rotation direction of the housing 2 to the control unit 5. It is configured to be possible. As shown in FIGS. 2 to 4, the acceleration sensor 8 has a substrate 81 and a case 82. The acceleration sensor 8 is an example of the "sensor unit" in the present invention.

The case 82 is made of resin and is symmetrically configured as shown in FIG. 2 and symmetrically as shown in FIG. The case 82 has a front plate 82A, a rear plate 82B, a lower plate 82C, a left plate 82D, and a right plate 82E.

The front plate 82A and the rear plate 82B are formed in a flat plate shape extending in the vertical direction and the horizontal direction.

The lower plate 82C is formed in a flat plate shape extending in the front-rear direction and the left-right direction. The lower plate 82C connects the lower end of the front plate 82A and the lower end of the rear plate 82B.

The left plate 82D and the right plate 82E are formed in a flat plate shape extending in the vertical direction and the front-rear direction. The left end plate 82D connects the left end portion of the front plate 82A and the left end portion of the rear plate 82B. The right plate 82E connects the right end portion of the front plate 82A and the right end portion of the rear plate 82B.

The upper end surfaces of the front plate 82A, the rear plate 82B, the left plate 82D, and the right plate 82E are flush with each other. Further, as shown in FIGS. 2 and 3, an opening is formed in the upper part of the case 82.

As shown in FIGS. 2 and 3, the substrate 81 is arranged in the case 82. The substrate 81 has a flat plate shape extending in the vertical direction and the horizontal direction. Various elements for detecting the acceleration in the rotational direction of the housing 2 are mounted on the rear surface of the substrate 81. The front surface of the substrate 81 is fixed to the rear surface of the front plate 82A of the case 82. A conducting wire 8A extends from the upper part of the substrate 81. The conductor 8A extends out of the accommodation wall 251 through an opening formed in the upper part of the case 82 and an opening formed by the right end surface of the upper left wall 251C of the accommodation wall 251 and the left end surface of the upper right wall 251D. There is.

Next, with reference to FIGS. 2 to 4, the mode in which the acceleration sensor support portion 25 supports the acceleration sensor 8 will be described in detail with reference to the dimensions and distances between the components.

As shown in FIG. 3, the distance from the upper end surface of the case 82 to the lower surface of the lower plate 82C is larger than the distance from the lower surface of the upper left wall 251C and the upper right wall 251D of the accommodating wall portion 251 to the upper surface of the lower wall 251B. Is also short. The upper end surface of the case 82 is in contact with the lower surface of the upper left wall 251C and the upper right wall 251D. Further, a third elastic body 9C is arranged between the lower plate 82C and the lower wall 251B. The lower surface of the lower plate 82C and the upper surface of the third elastic body 253C are in contact with each other, and the upper surface of the lower wall 251B and the lower surface of the third elastic body 9C are in contact with each other.

As shown in FIG. 3, the distance between the left side of the left plate 82D of the case 82 and the right side of the right plate 82E and the distance between the right side of the left side wall 251E of the accommodating wall portion 251 and the left side of the right side wall 251F. The distances of are substantially the same. The left plate 82D is in direct contact with the left wall 251E without an elastic body. Further, the right plate 82E is in direct contact with the right wall 251F without passing through an elastic body.

As described above, since the acceleration sensor 8 is in contact with the accommodating wall portion 251 of the acceleration sensor support portion 25 constituting the housing 2 in the left-right direction and is directly supported, when the housing 2 is accelerated in the rotational direction, the acceleration sensor 8 is supported. It is possible to appropriately detect the acceleration in the rotation direction of the housing 2. The left side wall 251E and the right side wall 251F are examples of the "support member" in the present invention.

As shown in FIG. 2, the distance between the front surface of the front plate 82A of the case 82 and the rear surface of the rear plate 82B is determined by the rear surface of the front wall 251A of the accommodating wall portion 251 and the rear end surface of the accommodating wall portion 251. It is configured to be shorter than the distance between the upper left wall 251C, the upper right wall 251D and the lower wall 251B). A second elastic body 9B is arranged between the front wall 251A and the front plate 82A. The rear surface of the front wall 251A and the front surface of the second elastic body 9B are in contact with each other, and the front surface of the front plate 82A and the rear surface of the second elastic body 9B are in contact with each other. Further, a first elastic body 9A is arranged between the pressing plate 252C and the rear plate 82B. The front surface of the pressing plate 252C and the rear surface of the first elastic body 9A are in contact with each other, and the rear surface of the rear plate 82B and the front surface of the first elastic body 9A are in contact with each other. In the state where the acceleration sensor 8 is sandwiched between the first elastic body 9A and the second elastic body 9B in this way, the holding plate 252C is fixed (not shown) to the housing by the screw 252A, whereby the acceleration sensor 8 and the elastic body are formed. It is prevented that 9 falls out of the accommodating wall portion 251.

In this way, since the acceleration sensor 8 is sandwiched between the first elastic body 9A and the second elastic body 9B in the front-rear direction, when the tip tool P vibrates in the front-rear direction (axis A direction), the said. It is possible to prevent the vibration in the front-rear direction from being transmitted to the acceleration sensor 8.

Further, since the elastic body 9 is used to absorb the vibration in the front-rear direction, it is not necessary to provide the acceleration sensor 8 on the grip portion 24C gripped by the operator, and the degree of freedom in arranging the acceleration sensor 8 is increased. Can be arranged at a position far from the axis A of the tip tool P. More specifically, in order to detect the acceleration in the rotation direction of the housing 2, it is preferable to separate the acceleration sensor 8 from the axis A as much as possible. However, in the present embodiment, the acceleration sensor 8 and the axis A are separated from each other. The distance is longer than the distance between the farthest end of the grip portion 24C from the axis A and the axis A. Further, the acceleration sensor 8 is provided so that the position in the vertical direction overlaps with the battery pack Q. Therefore, as compared with the case where the acceleration sensor 8 is arranged in the grip portion 24C, it is possible to appropriately detect the acceleration in the rotational direction generated in the housing 2.

Further, in the present embodiment, the acceleration sensor 8 is arranged so that the position in the vertical direction overlaps with the motor 3. According to such a configuration, since the acceleration sensor 8 is located on the side surface of the motor 3 which is less affected by the magnetic field generated from the stator 33 of the motor 3, the acceleration in the rotation direction of the tip tool P generated in the housing 2 is appropriate. Can be detected.

Further, in the present embodiment, as shown in FIG. 1, the acceleration sensor 8 and the control unit 5 are arranged between the back cover 23 and the motor housing 21. Therefore, wiring (conductor wire 8A) between the acceleration sensor 8 and the control unit 5 can be easily performed.

Next, the operation of the hammer drill 1 will be described with reference to FIGS. 1 to 3.

When the operator pulls the trigger 24A of the grip portion 24C, the control unit 5 starts the drive control of the motor 3. As a result, the motor 3 is driven, the driving force of the motor 3 is transmitted to the output unit 7 via the power transmission unit 6, and the tip tool P mounted on the tool holding unit 73 starts rotating and reciprocating.

At this time, the tip tool P may be caught in a hard portion of the work piece and the tip tool P may be locked, which may cause a kickback in which the housing 2 is largely swung by the rotation of the tip tool. In preparation for such a kickback, it is effective to detect the acceleration in the rotation direction generated in the housing by using an acceleration sensor. Also in the present embodiment, if the acceleration of the housing 2 detected by the acceleration sensor 8 exceeds a predetermined acceleration threshold value while the motor 3 is being driven, the control unit 5 stops the driving of the motor 3.

Conventionally, in order to prevent the accelerometer from erroneously detecting the axial vibration of the tip tool, the accelerometer is provided in the grip portion of the handle housing gripped by the operator with less axial vibration. rice field. On the other hand, when the acceleration sensor is provided in the grip portion, the acceleration sensor cannot be provided away from the axis of the tip tool, and it may not be possible to properly detect the acceleration in the rotation direction of the housing. There was sex.

However, in the present embodiment, the acceleration sensor 8 abuts and is directly supported by the accommodating wall portion 251 of the acceleration sensor support portion 25 constituting the housing 2 in the left-right direction, and the first elastic body 9A and the second elastic body 9A and the second in the front-rear direction. Since it is sandwiched by the elastic body 9B, the movement allowance of the acceleration sensor 8 with respect to the housing 2 in the front-rear direction is larger than the movement allowance of the acceleration sensor 8 with respect to the housing 2 in the rotation direction. Thereby, when the acceleration in the rotation direction is generated in the housing 2, it is possible to appropriately detect the acceleration in the rotation direction of the housing 2 without being affected by the vibration in the front-rear direction.

Further, since the elastic body 9 is used to absorb the vibration in the front-rear direction, it is not necessary to provide the acceleration sensor 8 on the grip portion 24C gripped by the operator, and the degree of freedom in arranging the acceleration sensor 8 is increased. Can be arranged at a position far from the axis A of the tip tool P. In the present embodiment, since the acceleration sensor 8 is arranged farther from the axis A than the end farthest from the axis A of the grip portion 24C, it is compared with the case where the acceleration sensor 8 is arranged in the grip portion 24C. Therefore, it becomes possible to appropriately detect the acceleration in the rotation direction generated in the housing 2.

As described above, the hammer drill 1, which is an example of the power working machine according to the first embodiment of the present invention, is housed in the housing 2, and is driven by the motor 3 having the rotating shaft 31 and the motor 3. , The output unit 7 to which the tip tool P can be attached and detached, and the rotary shaft 31 can be rotated in the rotational direction around the axis A extending in the front-rear direction by transmitting the rotational motion of the rotary shaft 31. It is provided with a power transmission unit 6 capable of converting rotary motion into reciprocating motion and reciprocating the tip tool P in the front-rear direction, and an acceleration sensor 8 supported by the housing 2 and capable of detecting the motion state of the housing 2. The acceleration sensor 8 is supported by the housing 2 so that the movement allowance of the acceleration sensor 8 with respect to the housing 2 in the front-rear direction is larger than the movement allowance of the acceleration sensor 8 with respect to the housing 2 in the rotation direction. As a result, the movement allowance of the acceleration sensor 8 with respect to the housing 2 in the rotation direction of the tip tool P is smaller than the movement allowance of the acceleration sensor 8 in the axis A direction (front-back direction) of the tip tool P. Therefore, it is possible to appropriately detect the acceleration of the housing 2 in the rotation direction of the tip tool P while suppressing the detection of the vibration of the tip tool P in the axis A direction.

Next, the hammer drill 100, which is an example of the power working machine according to the second embodiment of the present invention, will be described with reference to FIGS. 5 and 6. The hammer drill 100 basically has the same configuration as the hammer drill 1 according to the first embodiment, and the description of the same configuration as that of the hammer drill 1 will be omitted, and the different configurations will be mainly described. ..

In the second embodiment as well, the acceleration sensor 8 is sandwiched between the first elastic body 9A and the second elastic body 9B in the front-rear direction as in the first embodiment. When vibration in the axis A direction is generated in the tip tool P, it is possible to suppress transmission of the vibration in the axis A direction to the acceleration sensor 8.

Further, since the elastic body 9 is used to absorb the vibration in the front-rear direction, it is not necessary to provide the acceleration sensor 8 on the grip portion 24C to be gripped by the operator.

In the hammer drill 100 according to the second embodiment, the acceleration sensor support portion 125 is provided in the extension portion 24G of the handle housing 24 instead of the acceleration sensor support portion 25. More specifically, as shown in FIG. 5, the acceleration sensor support portion 125 is provided in the extension portion 24G so as to project forward from the inner surface of the extension portion 24G.

According to such a configuration, since the handle housing 24 is connected to the back cover 23 by the vibration reduction mechanism 2B that reduces the vibration in the front-rear direction, the handle housing 24 rotates more appropriately without detecting the vibration in the axis A direction. It is possible to detect acceleration in the direction.

Further, also in the second embodiment, since the acceleration sensor 8 is in contact with and directly supported by the accommodating wall portion 1251 of the acceleration sensor support portion 125 constituting the housing 2 in the left-right direction, the acceleration sensor 8 is supported by the housing 2 in the rotation direction. When acceleration is generated, it is possible to appropriately detect the acceleration in the rotation direction of the housing 2.

In the present embodiment, the hammer drills 1 and 100 have been described as an example, but the present invention is a power working machine driven by a motor other than the hammer drill, for example, a power working machine for rotating a tip tool such as a driver drill or a brush cutter. It can be applied to any of a power working machine for reciprocating a tip tool such as a saver saw and a jigsaw, and a power working machine for linearly moving a tip tool such as a chain saw.

1, 100 ... Hammer drill 2 ... Housing 3 ... Motor 4 ... Inverter circuit board 5 ... Control 6 ... Power transmission 7 ... Output 8 ... Accelerometer 9 ... Elastic body

Claims (15)

With the housing
A motor housed in the housing and having a rotating shaft,
An output unit that is driven by the motor and has a detachable tip tool,
A power transmission unit capable of transmitting the rotational motion of the rotating shaft to drive the tip tool in the front-rear direction, and
A battery pack that supplies power to the motor and
A sensor unit that is supported by the housing and can detect the motion state of the housing,
A cushioning member arranged between the housing and the sensor unit is provided.
The housing has a grip portion that extends in the vertical direction and includes a handle portion that is located behind the motor.
The battery pack is arranged below the handle portion.
The sensor unit, the up and down with the direction of the position is disposed in front of the battery pack overlaps way before Symbol battery pack, rearward and the battery of the axis of the rotary shaft position is the motor in the longitudinal direction A power working machine characterized in that it is arranged between the pack and the axis. The power working machine according to claim 1, wherein the cushioning member includes a plurality of elastic bodies supported by the housing so as to sandwich the sensor portion. The cushioning member has a first elastic body arranged between the housing and the sensor portion in the front-rear direction and a second elastic body arranged between the housing and the sensor portion in the vertical direction . The power working machine according to claim 1 or 2, wherein the power working machine includes a body. The housing has a wall surface facing the battery pack in the front-rear direction.
The power working machine according to any one of claims 1 to 3, wherein the sensor unit has a flat plate shape and is arranged so as to extend in the vertical direction and the horizontal direction along the wall surface. The motor is a brushless motor
Further having a control unit for controlling the drive of the motor,
The control unit is separated from the sensor unit and electrically connected to the sensor unit via a conducting wire.
The control unit is arranged so that the position in the vertical direction overlaps with the motor.
The power working machine according to any one of claims 1 to 4, wherein the sensor unit is arranged below the control unit. The housing further includes a motor housing that is connected to the handle and houses the motor internally.
The handle portion has a first connection portion that extends forward from the lower end portion of the grip portion and is rotatably connected to the motor housing with a rotation shaft extending in the left-right direction as a fulcrum. It has a substantially U-shape in the left-right direction including a second connection portion that extends forward from the upper end portion of the grip portion and is connected to the motor housing via a vibration reduction mechanism.
The power working machine according to claim 5, wherein the sensor unit and the control unit are supported by the motor housing. The handle portion has a substantially U-shape in the left-right direction including a first connecting portion extending forward from the lower end portion of the grip portion and a second connecting portion extending forward from the upper end portion of the grip portion. Doing
The power working machine according to any one of claims 1 to 5, wherein the sensor unit is arranged below the first connection unit. With the housing
A motor housed in the housing and having a rotating shaft,
An output unit that is driven by the motor and has a detachable tip tool,
A power transmission unit capable of transmitting the rotational motion of the rotating shaft to drive the tip tool in the front-rear direction, and
A battery pack that supplies power to the motor and
A sensor unit that is supported by the housing and can detect the motion state of the housing,
A cushioning member arranged between the housing and the sensor unit is provided.
The housing has a grip portion that extends in the vertical direction and includes a handle portion that is located behind the motor.
The battery pack is arranged below the handle portion.
The sensor unit is arranged in front of the battery pack so that the position in the vertical direction overlaps with the battery pack.
The sensor unit is supported by the housing so that the allowable movement amount of the sensor unit with respect to the housing in the front-rear direction is larger than the movement allowable amount of the sensor unit with respect to the housing in the left-right direction. dynamic force working machine shall be the feature. The power transmission unit can transmit the rotational motion of the rotary shaft to rotate the tip tool in the rotational direction around the axis extending in the front-rear direction, and convert the rotary motion of the rotary shaft into a reciprocating motion. It is possible to reciprocate the tip tool in the front-back direction.
The power working machine according to any one of claims 1 to 8, wherein the axis is arranged above the motor. The power working machine according to claim 9, wherein the sensor unit is supported by the housing via a cushioning member in the front-rear direction. The power working machine according to claim 10, wherein the sensor unit is directly supported by the housing in the left-right direction. The housing has a sensor portion support portion that supports the sensor portion, and has a sensor portion support portion.
The sensor portion support portion has a support member having a spring constant larger than that of the cushioning member.
The power working machine according to claim 11, wherein the sensor unit is supported by the support member in the left-right direction. With the housing
A motor housed in the housing and having a rotating shaft,
An output unit that is driven by the motor and has a detachable tip tool,
A power transmission unit capable of transmitting the rotational motion of the rotating shaft to drive the tip tool in the front-rear direction, and
A battery pack that supplies power to the motor and
A sensor unit that is supported by the housing and can detect the motion state of the housing,
A cushioning member arranged between the housing and the sensor unit is provided.
The housing includes a handle portion having a grip portion extending in the vertical direction and located behind the motor, and a motor housing connected to the handle portion and accommodating the motor inside.
The handle portion has a first connection portion that extends forward from the lower end portion of the grip portion and is rotatably connected to the motor housing with a rotation shaft extending in the left-right direction as a fulcrum. It has a substantially U-shape in the left-right direction including a second connection portion that extends forward from the upper end portion of the grip portion and is connected to the motor housing via a vibration reduction mechanism.
The handle portion has an extension portion that is arranged in front of the battery pack.
A power working machine characterized in that the sensor portion is provided on the extension portion of the handle portion. The battery pack is arranged below the handle portion.
The power working machine according to claim 13, wherein the sensor unit is arranged in front of the battery pack so that the position in the vertical direction overlaps with the battery pack. With the housing
A motor housed in the housing and having a rotating shaft,
An output unit that is driven by the motor and has a detachable tip tool,
A power transmission unit capable of transmitting the rotational motion of the rotating shaft to drive the tip tool in the front-rear direction, and
A battery pack that supplies power to the motor and
A sensor unit that is supported by the housing and can detect the motion state of the housing,
A cushioning member arranged between the housing and the sensor unit is provided.
The housing has a grip portion that extends in the vertical direction and includes a handle portion that is located behind the motor.
The battery pack is arranged below the handle portion.
The sensor unit is arranged in front of the battery pack so that the position in the vertical direction overlaps with the battery pack.
The housing has a wall surface facing the battery pack in the front-rear direction.
A power working machine having a flat plate shape and being arranged so as to extend in the vertical direction and the horizontal direction along the wall surface.

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