WO2020241086A1

WO2020241086A1 - Electric tool

Info

Publication number: WO2020241086A1
Application number: PCT/JP2020/016045
Authority: WO
Inventors: 高弘川上; 直樹副田; 博貴金子; 雄也田中
Original assignee: 株式会社マキタ
Priority date: 2019-05-29
Filing date: 2020-04-09
Publication date: 2020-12-03
Also published as: JP2020192655A

Abstract

The description discloses an electric tool. The electric tool may be provided with a motor, a power transmission mechanism connected to the motor, a control unit that controls driving of the motor, a housing that accommodates the motor, the power transmission mechanism, and the control unit, a tip tool holder connected to the power transmission mechanism and removably holding a tip tool, a handle removably attached to the housing, and a mechanical switch that detects whether the handle is attached to the housing. When the mechanical switch does not detect that the handle is attached to the housing, the control unit may inhibit the motor from rotating.

Description

Electric tool

The technology disclosed in this specification relates to power tools.

Japanese Patent Application Laid-Open No. 2005-138239 describes a motor, a power transmission mechanism connected to the motor, a control unit for controlling the drive of the motor, and a housing for accommodating the motor, the power transmission mechanism, and the control unit. A power tool having a tip tool holding portion connected to the power transmission mechanism and to which the tip tool can be attached and detached and a handle detachably attached to the housing is disclosed.

When the user uses the power tool, it is preferable that the user grips the handle and stably holds the power tool while performing the work. However, in a configuration in which the handle can be attached to and detached from the housing as in JP-A-2005-138239, the power tool may be used with the handle removed. The present specification provides a technique capable of preventing the power tool from being used with the handle removed.

This specification discloses power tools. The power tool includes a motor, a power transmission mechanism connected to the motor, a control unit that controls the drive of the motor, a housing that houses the motor, the power transmission mechanism, and the control unit, and the power transmission. A tip tool holder that is connected to the mechanism and allows the tip tool to be attached and detached, a handle that is detachably attached to the housing, and a mechanical switch that detects whether or not the handle is attached to the housing. You may have it. If the mechanical switch does not detect that the handle is attached to the housing, the control unit may prohibit rotation of the motor.

According to the above configuration, unless the mechanical switch detects that the handle is attached to the housing, the rotation of the motor is prohibited, thus preventing the power tool from being used with the handle removed. can do.

It is a perspective view which looked at the power tool 2 of Example 1 from the front right upper side. It is a vertical sectional view of the electric tool 2 of Example 1. FIG. FIG. 5 is a cross-sectional view of a front portion of the power tool 2 of the first embodiment in a state where the side grip 14 is attached to the gear housing 8. It is a perspective view which saw the microswitch 60 of the power tool 2 of Example 1 from the front right upper side. FIG. 5 is a cross-sectional view of a front portion of the power tool 2 of the first embodiment in a state where the side grip 14 is removed from the gear housing 8. FIG. 5 is a cross-sectional view of a front portion of the power tool 102 of the second embodiment in a state where the side grip 14 is removed from the gear housing 106. FIG. 5 is a cross-sectional view of a front portion of the power tool 202 of the third embodiment in a state where the side grip 14 is removed from the gear housing 206. FIG. 3 is a perspective view of the first cam member 214 of the power tool 202 of the third embodiment as viewed from the rear left upper side. FIG. 3 is a perspective view of the first cam member 214 of the power tool 202 of the third embodiment as viewed from the rear right upper side. FIG. 5 is a perspective view of the second cam member 216 of the power tool 202 of the third embodiment as viewed from the rear left upper side. FIG. 5 is a perspective view of the second cam member 216 of the power tool 202 of the third embodiment as viewed from the rear right upper side. It is a vertical sectional view of the front part of the power tool 202 of Example 3 in a state where the side grip 14 is removed from the gear housing 206. It is a vertical cross-sectional view of the front part of the power tool 202 of Example 3 in a state where the side grip 14 is attached to the gear housing 206. FIG. 5 is a vertical cross-sectional view of a front portion of the power tool 202 of the third embodiment in a state where the side grip 14 is attached to the gear housing 206 and tightened with a predetermined torque.

In the following, typical and non-limiting specific examples of the present invention will be described in detail with reference to the drawings. This detailed description is intended to provide those skilled in the art with details for implementing the preferred examples of the invention and is not intended to limit the scope of the invention. In addition, the additional features and inventions disclosed below may be used separately or together with other features and inventions to provide further improved power tools, methods of manufacture and use thereof.

In addition, the combination of features and processes disclosed in the following detailed description is not essential for carrying out the present invention in the broadest sense, and is particularly for explaining a typical specific example of the present invention. It is to be described. In addition, the various features of the above and below representative examples, as well as the various features of those described in the independent and dependent claims, are described herein in providing additional and useful embodiments of the invention. It does not have to be combined according to the specific examples given or in the order listed.

All features described herein and / or the scope of claims are separate, as a limitation to the disclosure at the time of filing and the specific matters claimed, apart from the composition of the features described in the examples and / or claims. It is intended to be disclosed independently of each other. In addition, all numerical ranges and statements relating to groups or groups are made with the intention of disclosing their intermediate composition as a limitation to the disclosure at the time of filing and the specific matters claimed.

In one or more embodiments, the power tool comprises a motor, a power transmission mechanism connected to the motor, a control unit that controls the drive of the motor, the motor, the power transmission mechanism, and the control unit. A housing that accommodates the above, a tip tool holding portion that is connected to the power transmission mechanism and has a detachable tip tool, a handle that is detachably attached to the housing, and whether the handle is attached to the housing. It may be provided with a mechanical switch that detects whether or not it is present. If the mechanical switch does not detect that the handle is attached to the housing, the control unit may prohibit rotation of the motor.

In one or more embodiments, the power tool may further include a main switch that switches between on and off in response to an operation from the user instructing the rotation of the motor. Even when it is detected that the handle is attached to the housing in the mechanical switch, the main switch is turned on when it is detected that the handle is attached to the housing. In the case of, the control unit may prohibit the rotation of the motor.

From the state where the handle is not attached to the housing and the main switch is on (in this case, motor rotation is prohibited), the user attaches the handle to the housing while keeping the main switch on. It may end up. In this case, if the mechanical switch detects that the handle is attached to the housing and immediately rotates the motor, the motor may rotate at a timing unintended by the user. According to the above configuration, it is possible to prevent the motor from rotating at a timing not intended by the user, and it is possible to ensure the safety of the user.

In one or more embodiments, the control unit in the mechanical switch when it is detected that the handle is attached to the housing and the main switch is switched from off to on. May rotate the motor.

According to the above configuration, the power tool can be operated while the safety of the user is ensured.

In one or more embodiments, the housing may include a first mounting portion to which the handle can be mounted and a second mounting portion to which the handle can be mounted in addition to the first mounting portion. Good. The mechanical switch may include a first mechanical switch corresponding to the first mounting portion and a second mechanical switch corresponding to the second mounting portion.

According to the above configuration, it is possible to prevent the power tool from being used with the handle removed for the power tool whose housing includes the first mounting portion and the second mounting portion.

In one or more embodiments, the mechanical switch may directly detect the movement of the handle.

According to the above configuration, the structure of the power tool can be simplified and the number of parts of the power tool can be reduced.

In one or more embodiments, the housing may have mounting holes that penetrate the housing from the outside to the inside. The handle may include a protrusion that penetrates the mounting hole when the handle is mounted in the housing. The mechanical switch is housed inside the housing and may be arranged so as to face the mounting hole on an extension of the central axis of the mounting hole.

According to the above configuration, it is possible to reliably detect whether or not the handle is attached to the housing by the mechanical switch while simplifying the structure of the power tool.

In one or more embodiments, the power tool is housed in the housing and may further include an intermediate member that operates in conjunction with attachment / detachment of the handle to the housing. The mechanical switch may detect the operation of the intermediate member.

According to the above configuration, the degree of freedom in arranging the mechanical switch in the power tool can be improved.

In one or more embodiments, the housing may have mounting holes that penetrate the housing from the outside to the inside. The handle may include a protrusion that penetrates the mounting hole when the handle is mounted in the housing. The mechanical switch may be housed inside the housing. The intermediate member may be interposed between the mechanical switch and the mounting hole.

In one or more embodiments, the power tool is housed inside the housing and may further include a switch case for holding the mechanical switch. One end of the intermediate member may be arranged so as to face the mechanical switch. The other end of the intermediate member may be fixed to the switch case. When the handle is attached to the housing, the intermediate member may be pressed by the protrusion and elastically deformed so that the intermediate member comes into contact with the mechanical switch. When the handle is removed from the housing, the intermediate member may be separated from the mechanical switch by an elastic restoring force.

According to the above configuration, the mechanical switch, the intermediate member, and the switch case can be handled as an integrated part, so that the power tool can be manufactured more easily.

In one or more embodiments, the handle may be attached to the housing by screwing it into the housing. The power tool may further include a torque detection mechanism that detects whether or not the tightening torque of the handle with respect to the housing has reached a predetermined torque.

According to the above configuration, it is possible to determine whether or not the handle is securely attached to the housing.

In one or more embodiments, the torque detection mechanism comprises a first cam member that is rotatable and axially immovable with respect to the housing and that is non-rotatable and axially non-rotatable with respect to the housing. A second cam member that can move to, an urging member that urges the second cam member in a direction close to the first cam member, and a direction in which the second cam member separates from the first cam member. It may be provided with a detection switch for detecting the movement of the. The first cam member may have a first cam surface. The second cam member may have a second cam surface that abuts on the first cam surface. The first cam member may rotate integrally with the handle when the handle is tightened to the housing. The first cam surface and the second cam surface are the first cam member when the first cam member rotates relative to the second cam member in a direction in which the handle is tightened to the housing. And the second cam member may have a shape of moving in a direction away from each other.

In the above configuration, when the handle is tightened with respect to the housing, the first cam member and the second cam member rotate relatively, and the second cam member moves in a direction away from the first cam member. I will go. Since the urging member acts on the second cam member in a direction close to the first cam member, the second cam member separates from the first cam member when the tightening torque for the handle housing is small. The detection switch does not work because it does not move much in the direction of the movement. On the other hand, when the tightening torque for the housing of the handle is large, the second cam member moves significantly in the direction away from the first cam member, and the detection switch operates. As described above, according to the above configuration, it is possible to realize a torque detection mechanism that detects whether or not the tightening torque for the housing of the handle has reached a predetermined torque with a simple configuration.

In one or more embodiments, the housing is formed in a cam accommodating groove accommodating the first cam member, the second cam member and the urging member, and an inner end of the cam accommodating groove. It may have a first opening and a second opening formed on the inner peripheral surface near the inner end of the cam accommodating groove. The handle may include a protrusion that penetrates the cam accommodating groove and the first opening and is screwed into the first cam member when the handle is attached to the housing. The mechanical switch is housed inside the housing and may be arranged on an extension of the shafts of the first cam member and the second cam member so as to face the first opening. The detection switch is housed inside the housing and may be arranged to face the second opening.

According to the above configuration, while simplifying the structure of the power tool, it is possible to reliably detect whether or not the handle is attached to the housing by the mechanical switch, and the detection switch reduces the tightening torque of the handle to the housing. It is possible to reliably detect whether or not a predetermined torque has been reached.

In one or more embodiments, the torque detection mechanism relative to the housing of the handle, even if the mechanical switch detects that the handle is attached to the housing. If it is not detected that the tightening torque has reached a predetermined torque, the control unit may prohibit the rotation of the motor.

According to the above configuration, it is possible to prevent the power tool from being used in a state where the handle is attached to the housing but is not securely attached.

In one or more embodiments, the power tool is detachably attached to the housing and may further include a battery that powers the motor and the control unit.

According to the above configuration, power can be supplied to the motor and the control unit without connecting to an external power supply with a cord.

In one or more embodiments, the power tool may be capable of using a grinding wheel as the tip tool. The power tool may function as a grinder.

According to the above configuration, it is possible to prevent the power tool that functions as a grinder from being used with the handle removed.

In one or more embodiments, the housing may include a grip. The user may be able to use the power tool with the grip held by one hand and the handle held by the other hand.

According to the above configuration, when using the power tool, the user can grip the grip with one hand and the handle with the other hand to stably hold the power tool.

(Example 1)
As shown in FIG. 1, the power tool 2 of this embodiment is, for example, a grinder. The power tool 2 includes a motor housing 4, a motor cover 6, a gear housing 8, a bearing box 10, a wheel cover 12, and a side grip 14. In the following description, the longitudinal direction of the motor housing 4 is referred to as the front-rear direction, the direction orthogonal to the front-rear direction is referred to as the left-right direction, and the direction orthogonal to the front-rear direction and the left-right direction is referred to as the up-down direction.

As shown in FIG. 2, the motor 16 is housed inside the front of the motor housing 4. The motor 16 is, for example, an inner rotor type brushless DC motor. The motor 16 has an output shaft 18 extending in the front-rear direction. A motor cover 6 is attached to the front end of the motor housing 4. The output shaft 18 is rotatably supported by the motor housing 4 via the bearing 20 and rotatably supported by the motor cover 6 via the bearing 22. A battery 24 is attached to the rear end of the motor housing 4. The battery 24 is a rechargeable secondary battery, such as a lithium ion battery. The battery 24 is a slide-type battery that can be attached to and detached from the motor housing 4 by sliding it in the vertical direction. A control unit 26 is housed inside the rear of the motor housing 4. The electric power supplied from the battery 24 is supplied to the motor 16 via the control unit 26. A slide switch 28 that can slide in the front-rear direction is provided on the front upper surface of the motor housing 4. The slide switch 28 can be switched between the front on position and the rear off position by a user operation. The position of the slide switch 28 is detected by the main switch 30 housed inside the motor housing 4. The main switch 30 is connected to the control unit 26. When the slide switch 28 is in the on position, the main switch 30 is turned on, power from the battery 24 is supplied to the motor 16 via the control unit 26, and the motor 16 rotates the output shaft 18. When the slide switch 28 is in the off position, the main switch 30 is turned off, the power supply of the battery 24 to the motor 16 is cut off, and the motor 16 stops the output shaft 18. A display unit 32 is provided on the upper surface behind the motor housing 4. The display unit 32 is connected to the control unit 26. The display unit 32 notifies the user of the operating state of the power tool 2 and the remaining battery level of the battery 24 by changing the display according to the operating state of the power tool 2 and the remaining battery level of the battery 24.

The gear housing 8 is attached to the front of the motor cover 6. Inside the gear housing 8, a first bevel gear 34 and a second bevel gear 36 arranged so as to mesh with each other are housed. The first bevel gear 34 is fixed to the front end of the output shaft 18. The second bevel gear 36 is fixed to the upper end of the spindle 38 extending in the vertical direction. Hereinafter, the first bevel gear 34 and the second bevel gear 36 are collectively referred to as a bevel gear 40. The bevel gear 40 is a reduction mechanism that reduces the rotation of the motor 16 and transmits it to the spindle 38, and can be called a power transmission mechanism. The gear housing 8 rotatably supports the upper end of the spindle 38 via a bearing 42. As shown in FIG. 1, a shaft lock 44 is provided on the upper surface of the gear housing 8. When the user operates the shaft lock 44 and pushes it downward, the rotation of the second bevel gear 36 is prohibited and the rotation of the spindle 38 is prohibited.

As shown in FIG. 2, the bearing box 10 is attached below the gear housing 8. The bearing box 10 rotatably supports the spindle 38 via the bearing 46. The spindle 38 is rotatable with respect to the bearing box 10 with respect to a rotation axis along the vertical direction. A grinding wheel 52 can be attached to the lower end of the spindle 38 via an inner flange 48 and an outer flange 50. The inner flange 48 is fitted to the spindle 38. The grinding wheel 52 is attached to the spindle 38 from below the inner flange 48 and is fitted to the inner flange 48. The outer flange 50 is screwed onto the spindle 38 from the lower end of the spindle 38, and sandwiches the grinding wheel 52 with the inner flange 48. In the power tool 2, when the motor 16 rotates, the grinding wheel 52 rotates around the rotation axis together with the spindle 38, so that the workpiece can be ground. The spindle 38 can also be said to be a tip tool holding portion that holds the grinding wheel 52, which is a tip tool. In this embodiment, the motor housing 4, the motor cover 6, the gear housing 8, and the bearing box 10 are collectively referred to as the housing 54.

The wheel cover 12 is detachably attached to the bearing box 10. The wheel cover 12 is formed so as to cover at least a part of the grinding wheel 52 when attached to the power tool 2. It can also be said that the wheel cover 12 has a shape that at least partially covers the spindle 38 when attached to the power tool 2. The wheel cover 12 prevents cutting powder from scattering to the user side when the grinding wheel 52 grinds the workpiece.

As shown in FIG. 1, the side grip 14 is detachably attached to the gear housing 8. When the user uses the power tool 2, the user can stably hold the power tool 2 by gripping the motor housing 4 with one hand and the side grip 14 with the other hand. ..

As shown in FIG. 3, the side grip 14 includes a protrusion 56. A male screw is formed on the outer peripheral surface of the protruding portion 56. The gear housing 8 is formed with a grip mounting hole 58. The grip mounting hole 58 is formed on the left surface of the gear housing 8. The grip mounting hole 58 is a substantially cylindrical hole extending along the central axis CL, penetrates from the outside to the inside of the gear housing 8, and has a female screw corresponding to the male screw of the protruding portion 56 on the inner peripheral surface. It is formed. The side grip 14 is attached to the gear housing 8 by screwing the protruding portion 56 into the grip mounting hole 58. The user can tighten the side grip 14 with respect to the gear housing 8 by rotating the side grip 14 with respect to the gear housing 8 around the central axis CL.

A micro switch 60 is housed inside the gear housing 8. As shown in FIG. 4, the micro switch 60 includes a switch case 62, a detection switch 64, and a detection arm 66. The switch case 62 is fixed to a support portion 68 (see FIG. 3) provided on the motor cover 6. The detection switch 64 is held in the switch case 62. The detection switch 64 is connected to the control unit 26. The detection arm 66 is an elongated plate-shaped member, the right end of which is arranged to face the detection switch 64, and the left end of which is fixed to the switch case 62. When the detection arm 66 comes into contact with the detection switch 64, the detection switch 64 outputs an on signal to the control unit 26, and when the detection arm 66 separates from the detection switch 64, the detection switch 64 outputs an off signal to the control unit 26. ..

As shown in FIG. 3, when the side grip 14 is attached to the grip mounting hole 58 of the gear housing 8, the protruding portion 56 penetrating the grip mounting hole 58 abuts and presses against the detection arm 66 of the micro switch 60. In this case, the detection arm 66 elastically deforms and comes into contact with the detection switch 64, and the detection switch 64 outputs an ON signal to the control unit 26. When the control unit 26 receives the ON signal from the detection switch 64, the control unit 26 determines that the side grip 14 is attached to the gear housing 8 and allows the motor 16 to rotate. In this state, when the user moves the slide switch 28 from the off position to the on position, the control unit 26 drives the motor 16 and the spindle 38 rotates.

As shown in FIG. 5, when the side grip 14 is removed from the gear housing 8, the detection arm 66 of the micro switch 60 is separated from the detection switch 64 by the elastic restoring force. In this case, the detection switch 64 outputs an off signal to the control unit 26. When the control unit 26 receives the off signal from the detection switch 64, the control unit 26 determines that the side grip 14 is not attached to the gear housing 8 and prohibits the rotation of the motor 16. In this state, even if the user moves the slide switch 28 from the off position to the on position, the control unit 26 does not drive the motor 16 and the spindle 38 does not rotate.

As shown in FIG. 5, the side grip 14 is not attached to the gear housing 8 and the slide switch 28 is in the on position (in this state, the rotation of the motor 16 is stopped). The user may attach the side grip 14 to the gear housing 8 while the switch 28 is in the on position. In this case, if the control unit 26 rotates the motor 16 when the detection switch 64 detects that the side grip 14 is attached to the gear housing 8, the spindle 38 rotates at a timing not intended by the user. There is a risk. Therefore, in the power tool 2 of the present embodiment, as shown in FIG. 3, when the user moves the slide switch 28 from the off position to the on position while the side grip 14 is attached to the gear housing 8. Only, the control unit 26 drives the motor 16 to rotate the spindle 38. With such a configuration, the safety of the user can be ensured.

As described above, the electric tool 2 of the present embodiment includes the motor 16, the bevel gear 40 (example of the power transmission mechanism) connected to the motor 16, the control unit 26 for controlling the drive of the motor 16, and the motor 16. A housing 54 that houses the bevel gear 40 and the control unit 26, and a spindle 38 (example of a tip tool holding portion) that is connected to the bevel gear 40 and has a detachable grinding wheel 52 (example of a tip tool) and a housing 54. It includes a possibly attached side grip 14 (example of a handle) and a detection switch 64 (example of a mechanical switch) that detects whether the side grip 14 is attached to the housing 54. When the detection switch 64 does not detect that the side grip 14 is attached to the housing 54, the control unit 26 prohibits the rotation of the motor 16.

According to the above configuration, unless it is detected by the detection switch 64 that the side grip 14 is attached to the housing 54, the rotation of the motor 16 is prohibited. Therefore, the electric tool 2 with the side grip 14 removed. Can be prevented from being used.

The power tool 2 of this embodiment further includes a main switch 30 that switches between on and off in response to an operation on the slide switch 28 by a user instructing the rotation of the motor 16. Even when the detection switch 64 detects that the side grip 14 is attached to the housing 54, the main switch 30 is set when it is detected that the side grip 14 is attached to the housing 54. When on, the control unit 26 prohibits the rotation of the motor 16.

According to the above configuration, it is possible to prevent the motor 16 from rotating at a timing not intended by the user, and it is possible to ensure the safety of the user.

In the power tool 2 of the present embodiment, when the detection switch 64 detects that the side grip 14 is attached to the housing 54 and the main switch 30 is switched from off to on, the control unit 26 The motor 16 is rotated.

According to the above configuration, the power tool 2 can be operated while the safety of the user is ensured.

The power tool 2 of this embodiment is housed in a housing 54, and further includes a detection arm 66 (an example of an intermediate member) that operates in conjunction with attachment / detachment of the side grip 14 to / from the housing 54. The detection switch 64 detects the operation of the detection arm 66.

According to the above configuration, the degree of freedom in arranging the detection switch 64 in the power tool 2 can be improved.

In the power tool 2 of this embodiment, the housing 54 has a grip mounting hole 58 (example of a mounting hole) that penetrates the housing 54 from the outside to the inside. The side grip 14 includes a protrusion 56 that penetrates the grip mounting hole 58 when the side grip 14 is mounted on the housing 54. The detection switch 64 is housed inside the housing 54. The detection arm 66 is interposed between the detection switch 64 and the grip mounting hole 58.

According to the above configuration, it is possible to reliably detect whether or not the side grip 14 is attached to the housing 54 by the detection switch 64 while simplifying the structure of the power tool 2.

The power tool 2 of this embodiment is housed inside the housing 54, and further includes a switch case 62 for holding the detection switch 64. One end of the detection arm 66 is arranged so as to face the detection switch 64. The other end of the detection arm 66 is fixed to the switch case 62. When the side grip 14 is attached to the housing 54, the detection arm 66 is pressed by the protrusion 56 and elastically deformed, so that the detection arm 66 comes into contact with the detection switch 64. When the side grip 14 is removed from the housing 54, the detection arm 66 separates from the detection switch 64 due to elastic restoring force.

According to the above configuration, the detection switch 64, the detection arm 66, and the switch case 62 can be handled as an integrated component, the micro switch 60, so that the power tool 2 can be manufactured more easily. Can be done.

The power tool 2 of this embodiment is detachably attached to the housing 54, and further includes a battery 24 that supplies power to the motor 16 and the control unit 26.

According to the above configuration, power can be supplied to the motor 16 and the control unit 26 without connecting to an external power supply with a cord.

In the power tool 2 of this embodiment, the grinding wheel 52 can be used as the tip tool. The power tool 2 functions as a grinder.

According to the above configuration, it is possible to prevent the power tool 2 functioning as a grinder from being used in a state where the side grip 14 is removed.

In the power tool 2 of this embodiment, the housing 54 includes a motor housing 4 (an example of a grip). The user can use the power tool 2 with one hand holding the motor housing 4 and the other hand holding the side grip 14.

According to the above configuration, when using the power tool 2, the user grips the motor housing 4 with one hand and the side grip 14 with the other hand to stably hold the power tool 2. can do.

(Example 2)
The power tool 102 of the present embodiment has substantially the same configuration as the power tool 2 of the first embodiment. Hereinafter, the power tool 102 of this embodiment will be described as being different from the power tool 2 of the first embodiment.

As shown in FIG. 6, the electric tool 102 of this embodiment includes a motor cover 104 and a gear housing 106 instead of the motor cover 6 and the gear housing 8. In this embodiment, the motor housing 4, the motor cover 104, the gear housing 106, and the bearing box 10 are collectively referred to as the housing 108. In this embodiment, the motor cover 104 does not include the support portion 68. Further, the gear housing 106 is formed with a plurality of

grip mounting holes

110 and 112. The grip mounting hole 110 is formed on the right surface of the gear housing 106. The grip mounting hole 112 is formed on the left surface of the gear housing 106. The grip mounting hole 110 is a substantially cylindrical hole extending along the central axis CL1, penetrates from the outside to the inside of the gear housing 106, and corresponds to the male screw of the protruding portion 56 of the side grip 14 on the inner peripheral surface. A female screw is formed. The grip mounting hole 112 is a substantially cylindrical hole extending along the central axis CL2, penetrates from the outside to the inside of the gear housing 106, and corresponds to the male screw of the protruding portion 56 of the side grip 14 on the inner peripheral surface. A female screw is formed. The side grip 14 is attached to the gear housing 106 by screwing the protrusion 56 into one of the plurality of

grip mounting holes

110, 112. When the side grip 14 is attached to the grip mounting hole 110, the user can tighten the side grip 14 to the gear housing 106 by rotating the side grip 14 around the central axis CL1 with respect to the gear housing 106. .. When the side grip 14 is attached to the grip mounting hole 112, the user can tighten the side grip 14 to the gear housing 106 by rotating the side grip 14 around the central axis CL2 with respect to the gear housing 106. ..

The power tool 102 of this embodiment includes a plurality of

detection switches

114 and 116 instead of the micro switch 60. Each of the plurality of

detection switches

114 and 116 corresponds to each of the plurality of

grip mounting holes

110 and 112. The plurality of

detection switches

114 and 116 are housed inside the gear housing 106. The detection switch 114 is arranged so as to face the grip mounting hole 110. The detection switch 116 is arranged so as to face the grip mounting hole 112. Each of the plurality of

detection switches

114 and 116 is connected to the control unit 26.

In the power tool 102 of this embodiment, when the side grip 14 is attached to the grip mounting hole 110 on the right side of the gear housing 106, the protruding portion 56 penetrating the grip mounting hole 110 abuts on the detection switch 114 and presses it. In this case, the detection switch 114 outputs an on signal to the control unit 26, and the detection switch 116 outputs an off signal to the control unit 26. Further, in the power tool 102 of the present embodiment, when the side grip 14 is attached to the grip mounting hole 112 on the left side of the gear housing 106, the protruding portion 56 penetrating the grip mounting hole 112 abuts and presses against the detection switch 116. In this case, the detection switch 114 outputs an off signal to the control unit 26, and the detection switch 116 outputs an on signal to the control unit 26. When the control unit 26 receives an on signal from any one of the detection switch 114 and the detection switch 116, the control unit 26 determines that the side grip 14 is attached to the gear housing 106 and allows the motor 16 to rotate. In this state, when the user moves the slide switch 28 to the on position, the control unit 26 drives the motor 16 and the spindle 38 rotates.

When the side grip 14 is removed from the gear housing 106, each of the plurality of

detection switches

114 and 116 outputs an off signal to the control unit 26. When the control unit 26 receives an off signal from each of the plurality of

detection switches

114 and 116, the control unit 26 determines that the side grip 14 is not attached to the gear housing 106 and prohibits the rotation of the motor 16. In this state, even if the user moves the slide switch 28 to the on position, the control unit 26 does not drive the motor 16 and the spindle 38 does not rotate.

From the state where the side grip 14 is not attached to the gear housing 106 and the slide switch 28 is in the on position (in this state, the rotation of the motor 16 is stopped), the slide switch 28 is set to the on position. As it is, the user may attach the side grip 14 to the grip mounting hole 110 or the grip mounting hole 112. In this case, when the detection switch 114 or the detection switch 116 detects that the side grip 14 is attached to the grip mounting hole 110 or the grip mounting hole 112, if the control unit 26 rotates the motor 16, the user However, the spindle 38 may rotate at an unintended timing. Therefore, in the power tool 102 of the present embodiment, only when the user moves the slide switch 28 from the off position to the on position while the side grip 14 is attached to the grip mounting hole 110 or the grip mounting hole 112. , The control unit 26 drives the motor 16 to rotate the spindle 38. With such a configuration, the safety of the user can be ensured.

As described above, the electric tool 102 of the present embodiment includes the motor 16, the bevel gear 40 (example of the power transmission mechanism) connected to the motor 16, the control unit 26 for controlling the drive of the motor 16, and the motor 16. A housing 108 that houses the bevel gear 40 and the control unit 26, and a spindle 38 (an example of a tip tool holding portion) that is connected to the bevel gear 40 and has a detachable grinding wheel 52 (an example of a tip tool) and a housing 108. It includes a possibly attached side grip 14 (example of a handle) and detection switches 114, 116 (example of a mechanical switch) that detect whether the side grip 14 is attached to the housing 108. When the detection switches 114 and 116 do not detect that the side grip 14 is attached to the housing 108, the control unit 26 prohibits the rotation of the motor 16.

According to the above configuration, unless it is detected by the detection switches 114 and 116 that the side grip 14 is attached to the housing 108, the rotation of the motor 16 is prohibited. Therefore, the motor 16 is electrically operated with the side grip 14 removed. It is possible to prevent the tool 102 from being used.

The power tool 102 of this embodiment further includes a main switch 30 that switches between on and off in response to an operation on the slide switch 28 by a user instructing the rotation of the motor 16. Even if the detection switches 114 and 116 detect that the side grip 14 is attached to the housing 108, the main switch is when it is detected that the side grip 14 is attached to the housing 108. When 30 is on, the control unit 26 prohibits the rotation of the motor 16.

In the power tool 102 of this embodiment, when the detection switches 114 and 116 detect that the side grip 14 is attached to the housing 108 and the main switch 30 is switched from off to on, the control unit 26 rotates the motor 16.

According to the above configuration, the power tool 102 can be operated while the safety of the user is ensured.

In the power tool 102 of this embodiment, the housing 108 has a grip mounting hole 110 (example of the first mounting portion) to which the side grip 14 can be mounted and a grip to which the side grip 14 can be mounted separately from the grip mounting hole 110. It is provided with a mounting hole 112 (an example of a second mounting portion). Of the detection switches 114 and 116, the detection switch 114 corresponds to the grip mounting hole 110, and the detection switch 116 corresponds to the grip mounting hole 112.

According to the above configuration, with respect to the power tool 102 in which the housing 108 includes the grip mounting hole 110 and the grip mounting hole 112, it is possible to prevent the power tool 102 from being used with the side grip 14 removed.

In the power tool 102 of this embodiment, the detection switches 114 and 116 directly detect the operation of the side grip 14.

According to the above configuration, the structure of the power tool 102 can be simplified and the number of parts of the power tool 102 can be reduced.

In the power tool 102 of this embodiment, the housing 108 has grip mounting holes 110 and 112 (examples of mounting holes) that penetrate the housing 108 from the outside to the inside. The side grip 14 includes a protrusion 56 that penetrates the

grip mounting holes

110 and 112 when the side grip 14 is attached to the housing 108. The detection switches 114 and 116 are housed inside the housing 108, and are arranged on the extension lines of the central axes CL1 and CL2 of the

grip mounting holes

110 and 112 so as to face the

grip mounting holes

110 and 112.

According to the above configuration, it is possible to reliably detect whether or not the side grip 14 is attached to the housing 108 by the detection switches 114 and 116 while simplifying the structure of the power tool 102.

The power tool 102 of this embodiment is detachably attached to the housing 108, and further includes a battery 24 that supplies electric power to the motor 16 and the control unit 26.

In the power tool 102 of this embodiment, the grinding wheel 52 can be used as the tip tool. The power tool 102 functions as a grinder.

According to the above configuration, it is possible to prevent the power tool 102 functioning as a grinder from being used in a state where the side grip 14 is removed.

In the power tool 102 of this embodiment, the housing 108 includes a motor housing 4 (an example of a grip). The user can use the electric tool 102 with one hand holding the motor housing 4 and the other hand holding the side grip 14.

According to the above configuration, when using the power tool 102, the user grips the motor housing 4 with one hand and the side grip 14 with the other hand to stably hold the power tool 102. can do.

(Example 3)
The power tool 202 of the present embodiment has substantially the same configuration as the power tool 2 of the first embodiment. Hereinafter, the power tool 202 of this embodiment will be described as being different from the power tool 2 of the first embodiment.

As shown in FIG. 7, the electric tool 202 of this embodiment includes a motor cover 204 and a gear housing 206 instead of the motor cover 6 and the gear housing 8. In this embodiment, the motor housing 4, the motor cover 204, the gear housing 206, and the bearing box 10 are collectively referred to simply as the housing 208. In this embodiment, the motor cover 204 does not include the support portion 68. Further, the gear housing 206 is formed with a grip mounting portion 210. The grip mounting portion 210 is formed on the left surface of the gear housing 206. The grip mounting portion 210 has a substantially cylindrical shape that protrudes outward from the outer surface of the gear housing 206. The grip mounting portion 210 is formed with a cam accommodating groove 212 having a substantially cylindrical shape extending along the central axis CL. Inside the cam accommodating groove 212, a first cam member 214, a second cam member 216, a compression spring 218, and a retaining member 220 are arranged.

As shown in FIG. 8, the first cam member 214 includes a base portion 222 and a first cam portion 224. The base portion 222 is formed in a substantially cylindrical shape extending along the central axis CL. A female screw corresponding to the male screw of the protruding portion 56 of the side grip 14 is formed on the inner peripheral surface of the base portion 222. As shown in FIG. 9, the first cam portion 224 is formed in a substantially cylindrical shape extending along the central axis CL, and has a shape in which the end portion on the side facing the second cam member 216 is cut out. doing. The outer diameter of the first cam portion 224 is smaller than the outer diameter of the base portion 222, and the inner diameter of the first cam portion 224 substantially coincides with the inner diameter of the base portion 222. A first cam surface having a first inclined portion 226, a first vertical portion 228, a second inclined portion 230, and a second vertical portion 232 on a surface of the first cam portion 224 facing the second cam member 216. 224a is formed. When the first cam member 214 is viewed from the side facing the second cam member 216, the first inclined portion 226 increases the angle around the central axis CL from one end 226a to the other end 226b. , Has a shape that increases in height from the base 222. The second inclined portion 230 has a shape rotationally symmetric with respect to the first inclined portion 226 with respect to the central axis CL. That is, when the first cam member 214 is viewed from the side of the second inclined portion 230 facing the second cam member 216, the angle around the central axis CL increases from one end 230a to the other 230b. It has a shape in which the height from the base 222 increases as the height increases. The first vertical portion 228 connects the other end portion 226b of the first inclined portion 226 and the one end portion 230a of the second inclined portion 230. The second vertical portion 232 connects the other end portion 230b of the second inclined portion 230 and the one end portion 226a of the first inclined portion 226.

As shown in FIG. 10, the second cam member 216 is formed in a substantially cylindrical shape extending along the central axis CL. The inner diameter and outer diameter of the second cam member 216 substantially coincide with the inner diameter and outer diameter of the first cam portion 224 of the first cam member 214. The surface of the second cam member 216 facing the first cam member 214 corresponds to the first inclined portion 226, the first vertical portion 228, the second inclined portion 230, and the second vertical portion 232 of the first cam surface 224a. Therefore, a second cam surface 242a having a first inclined portion 234, a first vertical portion 236, a second inclined portion 238, and a second vertical portion 240 is formed. The portion of the second cam member 216 on which the first inclined portion 234, the first vertical portion 236, the second inclined portion 238, and the second vertical portion 240 are formed is also referred to as a second cam portion 242. Further, as shown in FIG. 11, the second cam member 216 is formed with a plurality of guide grooves 244 and a contact piece 246. Each of the plurality of guide grooves 244 is formed on the outer peripheral surface of the second cam member 216 and extends in the direction along the central axis CL. The contact piece 246 is formed so as to project from the end of the second cam member 216.

As shown in FIG. 7, a step portion 212a is formed in the vicinity of the outer end portion of the cam accommodating groove 212. The first cam member 214 is mounted in the cam accommodating groove 212 in a state in which the base portion 222 is slidably mounted on the step portion 212a and the movement in the direction along the central axis CL is prohibited by the retaining member 220. Have been placed. That is, the first cam member 214 is held in the gear housing 206 so as to be immovable with respect to the gear housing 206 in the direction along the central axis CL and to be rotatable around the central axis CL. The second cam member 216 is arranged in the cam accommodating groove 212 so that the second cam portion 242 of the second cam member 216 faces the first cam portion 224 of the first cam member 214. On the inner peripheral surface near the inner end of the cam accommodating groove 212, a guide protrusion (not shown) extending in the direction along the central axis CL is formed corresponding to the guide groove 244 of the second cam member 216. .. The second cam member 216 is arranged in the cam accommodating groove 212 in a state where the guide groove 244 is slidably engaged with the guide protrusion. That is, the second cam member 216 is movable with respect to the gear housing 206 in the direction along the central axis CL, and is held in the gear housing 206 so as not to rotate around the central axis CL. The second cam member 216 is urged toward the first cam member 214 by a compression spring 218 arranged in the cam accommodating groove 212.

As shown in FIG. 12, a first detection switch 248 and a second detection switch 250 are arranged inside the gear housing 206. The first detection switch 248 is arranged so as to face the first opening 212b formed at the inner end of the cam accommodating groove 212, and is arranged on an extension line of the central axis CL. The second detection switch 250 is arranged so as to face the second opening 212c formed on the upper inner peripheral surface near the inner end portion of the cam accommodating groove 212, and is offset upward from the central axis CL. Have been placed. A detection arm 252 is provided in the vicinity of the second detection switch 250. One end of the detection arm 252 is arranged to face the second detection switch 250, and the other end is rotatably supported by the gear housing 206. Each of the first detection switch 248 and the second detection switch 250 is connected to the control unit 26.

As shown in FIG. 12, when the side grip 14 is not attached to the gear housing 206, the first detection switch 248 outputs an off signal to the control unit 26, and the second detection switch 250 also outputs an off signal to the control unit 26. Output. In this case, the control unit 26 determines that the side grip 14 is not attached to the grip attachment portion 210, and prohibits the rotation of the motor 16. In this state, even if the user moves the slide switch 28 to the on position, the control unit 26 does not drive the motor 16 and the spindle 38 does not rotate.

As shown in FIG. 13, when the side grip 14 is inserted into the grip mounting portion 210 of the gear housing 206 and rotated, the male screw of the protruding portion 56 and the female screw of the first cam member 214 are screwed together to form the protruding portion. 56 advances with respect to the first cam member 214, and the tip of the protruding portion 56 abuts and presses against the first detection switch 248. In this state, the first detection switch 248 outputs an on signal to the control unit 26, and the second detection switch 250 outputs an off signal to the control unit 26. In this case, the control unit 26 determines that the side grip 14 is attached to the grip mounting portion 210, but the tightening torque of the side grip 14 does not reach a predetermined torque, and prohibits the rotation of the motor 16. In this state, even if the user moves the slide switch 28 to the on position, the control unit 26 does not drive the motor 16 and the spindle 38 does not rotate.

From the state shown in FIG. 13, when the side grip 14 is further rotated with respect to the gear housing 206 and the side grip 14 is tightened with respect to the gear housing 206, the protruding portion 56 cannot advance any further, so that the first cam The member 214 rotates together with the side grip 14. In this case, since the first cam member 214 rotates relative to the second cam member 216, the first inclined portion 226 of the first cam surface 224a presses the first inclined portion 234 of the second cam surface 242a. As shown in FIG. 14, the second inclined portion 230 of the first cam surface 224a presses the second inclined portion 238 of the second cam surface 242a, so that the second cam member 216 is located along the central axis CL. 1 It moves in a direction away from the cam member 214. As a result, the contact piece 246 of the second cam member 216 abuts and presses the detection arm 252, and the detection arm 252 presses the second detection switch 250. In this state, the first detection switch 248 outputs an on signal to the control unit 26, and the second detection switch 250 also outputs an on signal to the control unit 26. In this case, the control unit 26 determines that the side grip 14 is attached to the grip mounting portion 210 and the tightening torque of the side grip 14 has reached a predetermined torque, and allows the motor 16 to rotate. In this state, when the user moves the slide switch 28 to the on position, the control unit 26 drives the motor 16 and the spindle 38 rotates. As described above, whether or not the tightening torque of the side grip 14 of the first cam member 214, the second cam member 216, the compression spring 218, the second detection switch 250, and the detection arm 252 has reached a predetermined torque. It constitutes a torque detection mechanism 254 that detects the cam.

From the state shown in FIG. 14, when the side grip 14 is further rotated with respect to the gear housing 206 and the side grip 14 is tightened with respect to the gear housing 206, the first inclined portion 226 of the first cam surface 224a is further tightened. Overtakes the first inclined portion 234 of the second cam surface 242a and faces the second inclined portion 238, and the second inclined portion 230 of the first cam surface 224a gets over the second inclined portion 238 of the second cam surface 242a. Since it faces the first inclined portion 226, as shown in FIG. 13, the second cam member 216 moves in the direction approaching the first cam member 214 along the central axis CL by the urging force of the compression spring 218. In this case, the contact piece 246 of the second cam member 216 is separated from the detection arm 252, and the detection arm 252 is separated from the second detection switch 250. In this state, the first detection switch 248 outputs an on signal to the control unit 26, and the second detection switch 250 outputs an off signal to the control unit 26, but the control unit 26 already has the tightening torque of the side grip 14. Since it is detected that the predetermined torque has been reached, the rotation of the motor 16 is allowed. In this state, when the user moves the slide switch 28 to the on position, the control unit 26 drives the motor 16 and the spindle 38 rotates.

As shown in FIG. 12, the side grip 14 is not attached to the gear housing 206, and the slide switch 28 is in the on position (in this state, the rotation of the motor 16 is stopped). The user may attach the side grip 14 to the gear housing 206 while the switch 28 is in the on position. In this case, the first detection switch 248 detects that the side grip 14 is attached to the gear housing 206, and then the second detection switch 250 detects that the tightening torque of the side grip 14 has reached a predetermined torque. Occasionally, if the control unit 26 rotates the motor 16, the spindle 38 may rotate at a timing not intended by the user. Therefore, in the power tool 202 of the present embodiment, as shown in FIG. 14, the first detection switch 248 detects that the side grip 14 is attached to the gear housing 206, and the tightening torque of the side grip 14 is predetermined. Only when the user moves the slide switch 28 from the off position to the on position after the second detection switch 250 detects that the torque has been reached, the control unit 26 drives the motor 16 to drive the spindle. Rotate 38. With such a configuration, the safety of the user can be ensured.

As described above, the electric tool 202 of the present embodiment includes the motor 16, the bevel gear 40 (example of the power transmission mechanism) connected to the motor 16, the control unit 26 for controlling the drive of the motor 16, and the motor 16. A housing 208 that houses the bevel gear 40 and the control unit 26, and a spindle 38 (an example of a tip tool holding portion) that is connected to the bevel gear 40 and has a detachable grinding wheel 52 (an example of a tip tool) and a housing 208. It includes a possibly attached side grip 14 (example of a handle) and a first detection switch 248 (example of a mechanical switch) that detects whether the side grip 14 is attached to the housing 208. When the first detection switch 248 does not detect that the side grip 14 is attached to the housing 208, the control unit 26 prohibits the rotation of the motor 16.

According to the above configuration, unless it is detected by the first detection switch 248 that the side grip 14 is attached to the housing 208, the rotation of the motor 16 is prohibited. Therefore, the motor 16 is electrically operated with the side grip 14 removed. It is possible to prevent the tool 202 from being used.

The power tool 202 of this embodiment further includes a main switch 30 that switches between on and off in response to an operation on the slide switch 28 by the user instructing the rotation of the motor 16. Even if the first detection switch 248 detects that the side grip 14 is attached to the housing 208, the main switch is when it is detected that the side grip 14 is attached to the housing 208. When 30 is on, the control unit 26 prohibits the rotation of the motor 16.

In the power tool 202 of the present embodiment, when the first detection switch 248 detects that the side grip 14 is attached to the housing 208 and the main switch 30 is switched from off to on, the control unit 26 rotates the motor 16.

According to the above configuration, the power tool 202 can be operated while the safety of the user is ensured.

In the power tool 202 of this embodiment, the first detection switch 248 directly detects the operation of the side grip 14.

According to the above configuration, the structure of the power tool 202 can be simplified and the number of parts of the power tool 202 can be reduced.

In the power tool 202 of this embodiment, the housing 208 has a cam accommodating groove 212 and a first opening 212b (example of a mounting hole) that penetrate the housing 208 from the outside to the inside. The side grip 14 includes a protrusion 56 that penetrates the cam accommodating groove 212 and the first opening 212b when the side grip 14 is attached to the housing 208. The first detection switch 248 is housed inside the housing 208, and is arranged on the extension line of the central axis CL of the cam housing groove 212 and the first opening 212b so as to face the first opening 212b.

According to the above configuration, it is possible to reliably detect whether or not the side grip 14 is attached to the housing 208 by the first detection switch 248 while simplifying the structure of the power tool 202.

In the power tool 202 of this embodiment, the side grip 14 is attached to the housing 208 by screwing it into the housing 208. The power tool 202 further includes a torque detection mechanism 254 that detects whether or not the tightening torque of the side grip 14 with respect to the housing 208 has reached a predetermined torque.

According to the above configuration, it is possible to determine whether or not the side grip 14 is securely attached to the housing 208.

In the power tool 202 of this embodiment, the torque detection mechanism 254 is rotatable with respect to the housing 208 and is immovable with respect to the first cam member 214, and is immovable with respect to the housing 208 in the axial direction. A second cam member 216 that can be moved to, a compression spring 218 (an example of the urging member) that urges the second cam member 216 in a direction close to the first cam member 214, and a first cam member 216. A second detection switch 250 (example of a detection switch) for detecting movement in a direction away from the cam member 214 is provided. The first cam member 214 has a first cam surface 224a. The second cam member 216 has a second cam surface 242a that abuts on the first cam surface 224a. The first cam member 214 rotates integrally with the side grip 14 when the side grip 14 is tightened to the housing 208. The first cam surface 224a and the second cam surface 242a are the first cam members when the first cam member 214 rotates relative to the second cam member 216 in the direction in which the side grip 14 is tightened to the housing 208. The 214 and the second cam member 216 have a shape of moving in a direction away from each other.

According to the above configuration, it is possible to realize a torque detection mechanism 254 that detects whether or not the tightening torque of the side grip 14 with respect to the housing 208 has reached a predetermined torque with a simple configuration.

In the power tool 202 of this embodiment, the housing 208 has a cam accommodating groove 212 for accommodating the first cam member 214, the second cam member 216, and the compression spring 218, and a second cam accommodating groove 212 formed at the inner end portion of the cam accommodating groove 212. It has one opening 212b and a second opening 212c formed on the inner peripheral surface near the inner end of the cam accommodating groove 212. The side grip 14 includes a protrusion 56 that penetrates the cam accommodating groove 212 and the first opening 212b and is screwed into the first cam member 214 when the side grip 14 is attached to the housing 208. The first detection switch 248 is housed inside the housing 208 and is arranged on an extension of the axes of the first cam member 214 and the second cam member 216 so as to face the first opening 212b. The second detection switch 250 is housed inside the housing 208 and is arranged to face the second opening 212c.

According to the above configuration, while simplifying the structure of the power tool 202, it is possible to reliably detect whether or not the side grip 14 is attached to the housing 208 by the first detection switch 248, and the second detection switch. With the 250, it is possible to reliably detect whether or not the tightening torque of the side grip 14 with respect to the housing 208 has reached a predetermined torque.

In the power tool 202 of the present embodiment, even when the first detection switch 248 detects that the side grip 14 is attached to the housing 208, the torque detection mechanism 254 detects that the side grip 14 is attached to the housing 208. If it is not detected that the tightening torque for 208 has reached a predetermined torque, the control unit 26 prohibits the rotation of the motor 16.

According to the above configuration, it is possible to prevent the power tool 202 from being used in a state where the side grip 14 is attached to the housing 208 but is not securely attached.

The power tool 202 of this embodiment is detachably attached to the housing 208, and further includes a battery 24 that supplies power to the motor 16 and the control unit 26.

In the power tool 202 of this embodiment, the grinding wheel 52 can be used as the tip tool. The power tool 202 functions as a grinder.

According to the above configuration, it is possible to prevent the power tool 202 functioning as a grinder from being used in a state where the side grip 14 is removed.

In the power tool 202 of this embodiment, the housing 208 includes a motor housing 4 (an example of a grip). The user can use the power tool 202 with one hand holding the motor housing 4 and the other hand holding the side grip 14.

According to the above configuration, when using the power tool 202, the user grips the motor housing 4 with one hand and the side grip 14 with the other hand to stably hold the power tool 202. can do.

(Modification example)
In the above embodiment, the

electric tools

2, 102, 202 are grinders, the power transmission mechanism is a bevel gear 40, the tip tool is a grinding wheel 52, the tip tool holding portion is a spindle 38, and the grip is a motor housing. The case where the number is 4 and the handle is the side grip 14 has been described. Unlike this, the

power tools

2, 102, 202 may be other types of power tools such as driver drills and hammer drills. Further, the power transmission mechanism may be another type of power transmission mechanism, the tip tool may be another type of tip tool, and the tip tool holding portion is another type of tip tool holding portion. The grip may be another type of grip, and the handle may be another type of handle.

In the above embodiment, the configuration in which the

power tools

2, 102, 202 are supplied with power from the detachable battery 24 to the

housings

54, 108, 208 has been described. Unlike this, the

power tools

2, 102, 202 may be configured to be supplied with electric power from an external power source via a cord.

Claims

With the motor
The power transmission mechanism connected to the motor and
A control unit that controls the drive of the motor and
A housing that houses the motor, the power transmission mechanism, and the control unit,
A tip tool holder that is connected to the power transmission mechanism and allows the tip tool to be attached and detached.
A handle detachably attached to the housing and
It is equipped with a mechanical switch that detects whether the handle is attached to the housing.
A power tool in which the control unit prohibits rotation of the motor when the mechanical switch does not detect that the handle is attached to the housing.
It also has a main switch that switches between on and off in response to an operation from the user instructing the rotation of the motor.
Even when it is detected that the handle is attached to the housing in the mechanical switch, the main switch is turned on when it is detected that the handle is attached to the housing. In the case of, the power tool according to claim 1, wherein the control unit prohibits the rotation of the motor.
2. The control unit rotates the motor when it is detected in the mechanical switch that the handle is attached to the housing and the main switch is switched from off to on. Power tools.
The housing includes a first mounting portion to which the handle can be mounted, and a second mounting portion to which the handle can be mounted, in addition to the first mounting portion.
The mechanical switch according to any one of claims 1 to 3, wherein the mechanical switch includes a first mechanical switch corresponding to the first mounting portion and a second mechanical switch corresponding to the second mounting portion. Electric tool.
The power tool according to any one of claims 1 to 4, wherein the mechanical switch directly detects the operation of the handle.
The housing has a mounting hole that penetrates the housing from the outside to the inside.
The handle comprises a protrusion that penetrates the mounting hole when the handle is mounted in the housing.
The power tool according to claim 5, wherein the mechanical switch is housed inside the housing and is arranged so as to face the mounting hole on an extension line of a central axis of the mounting hole.
It further comprises an intermediate member that is housed in the housing and operates in conjunction with the attachment and detachment of the handle to and from the housing.
The power tool according to any one of claims 1 to 4, wherein the mechanical switch detects the operation of the intermediate member.
The housing has a mounting hole that penetrates the housing from the outside to the inside.
The handle comprises a protrusion that penetrates the mounting hole when the handle is mounted in the housing.
The mechanical switch is housed inside the housing.
The power tool according to claim 7, wherein the intermediate member is interposed between the mechanical switch and the mounting hole.
It is housed inside the housing and further comprises a switch case for holding the mechanical switch.
One end of the intermediate member is arranged so as to face the mechanical switch.
The other end of the intermediate member is fixed to the switch case.
When the handle is attached to the housing, the intermediate member is pressed by the protrusion and elastically deformed, so that the intermediate member comes into contact with the mechanical switch.
The power tool according to claim 8, wherein when the handle is removed from the housing, the intermediate member is separated from the mechanical switch by an elastic restoring force.
The handle is attached to the housing by screwing it into the housing.
The power tool according to any one of claims 1 to 9, further comprising a torque detection mechanism for detecting whether or not the tightening torque of the handle to the housing of the power tool has reached a predetermined torque.
The torque detection mechanism
A first cam member that is rotatable with respect to the housing and cannot move in the axial direction,
A second cam member that is non-rotatable with respect to the housing and can move in the axial direction,
An urging member that urges the second cam member in a direction close to the first cam member, and
A detection switch for detecting the movement of the second cam member in a direction away from the first cam member is provided.
The first cam member has a first cam surface and has a first cam surface.
The second cam member has a second cam surface that abuts on the first cam surface.
The first cam member rotates integrally with the handle when the handle is tightened to the housing.
When the first cam surface and the second cam surface rotate relative to the second cam member in a direction in which the handle is tightened to the housing, the first cam member The power tool according to claim 10, which has a shape in which the second cam member and the second cam member move in directions away from each other.
The housing
A cam accommodating groove accommodating the first cam member, the second cam member, and the urging member,
A first opening formed at the inner end of the cam accommodating groove,
It has a second opening formed on the inner peripheral surface near the inner end of the cam accommodating groove.
The handle is provided with a protrusion that penetrates the cam accommodating groove and the first opening and is screwed into the first cam member when the handle is attached to the housing.
The mechanical switch is housed inside the housing and is arranged on an extension of the shafts of the first cam member and the second cam member so as to face the first opening.
The power tool according to claim 11, wherein the detection switch is housed inside the housing and is arranged so as to face the second opening.
Even when the mechanical switch detects that the handle is attached to the housing, the torque detection mechanism detects that the tightening torque of the handle with respect to the housing has reached a predetermined torque. If not, the power tool according to any one of claims 10 to 12, wherein the control unit prohibits the rotation of the motor.
The power tool according to any one of claims 1 to 13, which is detachably attached to the housing and further includes a battery for supplying electric power to the motor and the control unit.
A grinding wheel can be used as the tip tool.
The power tool according to any one of claims 1 to 14, which functions as a grinder.
The housing has a grip
The power tool according to any one of claims 1 to 15, wherein the power tool can be used in a state where the user holds the grip with one hand and holds the handle with the other hand.