IP Library › Granted Patent US 12,246,410
Granted Patent B2
US 12,246,410 · App. 17/799,827 · Granted Mar 11, 2025

Electric power tool

Inventors: Akira Mizutani (Anjo, JP); Ryosuke Otani (Anjo, JP); Fumiyoshi Saito (Anjo, JP)
Assignee: MAKITA CORPORATION
B24B49/10B24B47/12B25F5/02B24B23/028
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Quick Facts
Patent No.
US 12,246,410
App. No.
17/799,827
Granted
Mar 11, 2025
Kind
B2
Abstract

An electric power tool. The electric power tool may include: a motor; a control device configured to control the motor; a power transmission mechanism connected to the motor; a housing that houses the motor, the control device and the power transmission mechanism; an end tool holder connected to the power transmission mechanism; an accessory configured to be detachably attached to the housing; and a detector configured to detect whether the accessory is attached or not. The detector may include: a link member configured to move with respect to the housing according to the accessory being attached or detached; a magnet fixed in position with respect to one of the link member and the housing; and a magnetic sensor fixed in position with respect to another of the link member and the housing.

Claims (138)

1. An electric power tool comprising:

a motor;

a control device configured to control the motor;

a power transmission mechanism connected to the motor;

a housing that houses the motor, the control device and the power transmission mechanism;

an end tool holder connected to the power transmission mechanism;

an accessory configured to be detachably attached to the housing; and

a detector configured to detect whether the accessory is attached or not,

wherein the detector comprises:

a link member configured to move with respect to the housing according to the accessory being attached or detached;

a magnet fixed in position with respect to one of the link member and the housing; and

a magnetic sensor fixed in position with respect to another of the link member and the housing,

the link member comprises:

a movement member configured to move with respect to the housing according to the accessory being attached or detached; and

a slide member configured to slide with respect to the housing according to moving of the movement member,

the slide member comprises:

a slide bar extending along a longitudinal direction of the electric power tool;

a movement portion disposed at one end of the slide bar and configured to move along with the movement member; and

a mount portion disposed at another end of the slide bar and in which one of the magnet and the magnetic sensor is mounted, and

the one of the magnet and the magnetic sensor that is mounted in the mount portion is located on an opposite side from the movement member as seen from the motor in the longitudinal direction of the electric power tool.

2. The electric power tool according to claim 1 , wherein the magnet is fixed in position with respect to the link member, and

the magnetic sensor is fixed in position with respect to the housing.

3. The electric power tool according to claim 1 , wherein the slide member is configured to move along the longitudinal direction of the electric power tool with respect to the housing.

4. The electric power tool according to claim 1 , wherein the link member further comprises a bias member biasing the slide member.

5. The electric power tool according to claim 1 , wherein the motor is housed in a motor housing chamber, and

the magnet and the magnetic sensor are housed in a sensor housing chamber arranged separately from the motor housing chamber.

6. The electric power tool according to claim 5 , wherein an opening through which a wiring is to pass is defined in the sensor housing chamber, the wiring being configured to connect the magnetic sensor and the control device to each other, and

the electric power tool further comprises a sealing member closing the opening around the wiring.

7. The electric power tool according to claim 5 , wherein the sensor housing chamber is disposed on an outer surface of the housing.

8. The electric power tool according to claim 1 , further comprising a magnetic shield member covering an outside of the magnetic sensor.

9. The electric power tool according to claim 1 , wherein the magnetic sensor is arranged on an opposite side from the power transmission mechanism in the longitudinal direction of the power tool as seen from the motor.

10. The electric power tool according to claim 1 , further comprising:

a power cable configured to be connected to an AC power source; and

a power circuit configured to convert AC power supplied from the power cable to DC power.

11. The electric power tool according to claim 1 , further comprising a battery pack configured to be detachably attached to the housing,

wherein the electric power tool is configured to be operated by DC power supplied from the battery pack.

12. The electric power tool according to claim 1 , wherein the control device is configured to prohibit the motor from being driven when the detector does not detect that the accessory is attached.

13. The electric power tool according to claim 1 , wherein the accessory is a wheel cover.

14. An electric power tool comprising:

a motor;

a control device configured to control the motor;

a power transmission mechanism connected to the motor;

a housing that houses the motor, the control device and the power transmission mechanism;

an end tool holder connected to the power transmission mechanism;

an accessory configured to be detachably attached to the housing; and

a detector configured to detect whether the accessory is attached or not,

wherein the detector comprises:

a link member configured to move with respect to the housing according to the accessory being attached or detached;

a magnet fixed in position with respect to one of the link member and the housing; and

a magnetic sensor fixed in position with respect to another of the link member and the housing,

a slide groove and a sensor housing chamber communicating with the slide groove are disposed on an outer surface of the housing,

the link member comprises a slide member arranged from the slide groove over the sensor housing chamber, and configured to slide with respect to the housing,

the magnet is fixed in position with respect to the slide member,

the magnetic sensor is arranged in the sensor housing chamber, and

the electric power tool further comprises a sensor cover that covers the slide groove and the sensor housing chamber.

15. The electric power tool according to claim 14 , wherein the sensor cover incorporates therein a magnetic shield member covering the sensor housing chamber.

16. The electric power tool according to claim 14 , wherein a first spring receiving wall is disposed in the slide groove or the sensor housing chamber of the housing,

the slide member comprises a second spring receiving wall, and

the link member further comprises a compression spring having one end in contact with the first spring receiving wall and another end in contact with the second spring receiving wall.

17. The electric power tool according to claim 14 , wherein the link member further comprises:

a base member fixed on the outer surface of the housing; and

a swing member configured to swing with respect to the base member according to the accessory being attached or detached, and

the slide member is configured to slide with respect to the housing according to swinging of the swing member.

18. The electric power tool according to claim 17 , wherein the base member comprises a groove in which the swing member is arranged, and

the groove is covered by the sensor cover.

19. The electric power tool according to claim 14 , wherein a vicinity of one end of the sensor cover is fixed to the housing by a screw, and a vicinity of another end of the sensor cover is fixed to the housing by another screw.

20. The electric power tool according to claim 14 , wherein one end of the sensor cover is inserted into an inside of the housing, and a vicinity of another end of the sensor cover is fixed to the housing by a screw.

21. An electric power tool comprising:

a motor;

a control device configured to control the motor;

a power transmission mechanism connected to the motor;

a housing that houses the motor, the control device and the power transmission mechanism;

an end tool holder connected to the power transmission mechanism;

an accessory configured to be detachably attached to the housing; and

a detector configured to detect whether the accessory is attached or not,

wherein the detector comprises:

a link member configured to move with respect to the housing according to the accessory being attached or detached;

a magnet fixed in position with respect to one of the link member and the housing; and

a magnetic sensor fixed in position with respect to another of the link member and the housing,

the magnet is fixed in position with respect to the link member, the magnetic sensor is fixed in position with respect to the housing, the link member comprises:

a swing member configured to swing with respect to the housing according to the accessory being attached or detached; and

a slide member configured to slide with respect to the housing according to swinging of the swing member,

the slide member is configured to move along a longitudinal direction of the electric power tool with respect to the housing,

the link member further comprises a bias member biasing the slide member,

the motor is housed in a motor housing chamber, the magnet and the magnetic sensor are housed in a sensor housing chamber arranged separately from the motor housing chamber,

an opening through which a wiring is to pass is defined in the sensor housing chamber, the wiring being configured to connect the magnetic sensor and the control device to each other,

the electric power tool further comprises a sealing member closing the opening around the wiring, the sensor housing chamber is disposed on an outer surface of the housing,

the electric power tool further comprises a magnetic shield member covering an outside of the magnetic sensor,

the magnetic sensor is arranged on an opposite side from the power transmission mechanism in the longitudinal direction of the power tool as seen from the motor,

a slide groove is disposed on an outer surface of the housing,

the sensor housing chamber communicates with the slide groove,

the slide member is arranged from the slide groove over the sensor housing chamber,

the magnet is fixed in position with respect to the slide member,

the magnetic sensor is arranged in the sensor housing chamber,

the electric power tool further comprises a sensor cover that covers the slide groove and the sensor housing chamber,

the sensor cover incorporates therein the magnetic shield member,

the magnetic shield member covers the sensor housing chamber,

a first spring receiving wall is disposed in the slide groove or the sensor housing chamber of the housing,

the slide member comprises a second spring receiving wall,

the link member further comprises a compression spring, as the bias member, having one end in contact with the first spring receiving wall and another end in contact with the second spring receiving wall,

the link member further comprises:

a base member fixed on the outer surface of the housing; and

the swing member configured to swing with respect to the base member according to the accessory being attached or detached,

the base member comprises a groove in which the swing member is arranged,

the groove of the base member is covered by the sensor cover,

a vicinity of one end of the sensor cover is fixed to the housing by a screw, and one end of the sensor cover is inserted into an inside of the housing,

the control device is configured to prohibits the motor from being driven, when the detector does not detect that the accessory is attached, and

the accessory is a wheel cover.

22. An electric power tool comprising:

a motor;

a control device configured to control the motor;

a power transmission mechanism connected to the motor;

a housing that houses the motor, the control device and the power transmission mechanism;

an end tool holder connected to the power transmission mechanism;

an accessory configured to be detachably attached to the housing; and

a detector configured to detect whether the accessory is attached or not,

wherein the detector comprises:

a link member configured to move with respect to the housing according to the accessory being attached or detached;

a magnet fixed in position with respect to one of the link member and the housing; and

a magnetic sensor fixed in position with respect to another of the link member and the housing,

the link member comprises:

a movement member configured to move with respect to the housing according to the accessory being attached or detached; and

a slide member configured to slide with respect to the housing according to moving of the movement member,

the slide member comprises:

a slide bar extending along a longitudinal direction of the electric power tool;

a movement portion disposed at one end of the slide bar and configured to move along with the movement member; and

a mount portion disposed at another end of the slide bar and in which one of the magnet and the magnetic sensor is mounted, and

the one of the magnet and the magnetic sensor that is mounted in the mount portion is located on an opposite side from the movement member as seen from the motor in the longitudinal direction of the electric power tool,

when a position of the link member with respect to the housing with the accessory detached from the housing is defined as a detachment position and

the position of the link member with respect to the housing with the accessory attached to the housing is defined as an attachment position,

the link member is configured to move from the detachment position to the attachment position via an intermediate position, and

at the intermediate position, a distance between the magnet and the magnetic sensor is smaller than at the detachment position and the attachment position.

23. The electric power tool according to claim 22 , wherein

when the link member is located at the detachment position, the magnet is offset from in a direction in which the magnet separates away from the end tool holder, and

when the link member is located at the attachment position, the magnet is offset from the magnetic sensor in a direction in which the magnet approaches the end tool holder.

24. The electric power tool according to claim 22 , further comprising a bias member biasing the link member toward the detachment position with respect to the housing, wherein

with the accessory detached from the housing, the link member is held in the detachment position by a biasing force of the bias member, and

by the accessory being attached to the housing, the link member moves from the detachment position to the attachment position against the biasing force of the bias member.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 15, 2022
From: MIZUTANI, AKIRA; OTANI, RYOSUKE; SAITO, FUMIYOSHI
To: MAKITA CORPORATION
Reel/Frame 060809/0681 →
Priority Claims (1)
JP 2020-024528 · Feb 17, 2020 · national
Continuity (1)
Related Publication 20230079761A1 · Mar 16, 2023
References Cited (19)
US 20060016678A1 · Mayer · 2006 [cited by examiner]
US 20150263592A1 · Kawakami · 2015 [cited by examiner]
US 20170106490A1 · Privett, Jr. · 2017 [cited by examiner]
US 20170165824A1 · Takeda · 2017 [cited by examiner]
US 20180180497A1 · Nishiguchi · 2018 [cited by examiner]
US 20180272494A1 · Schadow · 2018 [cited by examiner]
US 20180281146A1 · Tomonaga · 2018 [cited by examiner]
US 20210220959A1 · Matsubara et al. · 2021 [cited by applicant]
CN 202083441U · 2011 [cited by applicant]
CN 106488830A · 2017 [cited by applicant]
JP 2014133277A · 2014 [cited by applicant]
WO 2017051893A1 · 2017 [cited by applicant]
WO 2019191443A1 · 2019 [cited by applicant]
WO 2020054631A1 · 2020 [cited by applicant]
Apr. 15, 2023 Office Action issued in Chinese Patent Application No. 202080096822.8. [cited by applicant]
Mar. 9, 2021 International Search Report issued in International Patent Application No. PCT/JP2020/046927. [cited by applicant]
Mar. 9, 2021 Written Opinion of the International Searching Authority issued in International Patent Application No. PCT/JP2020/046927. [cited by applicant]
Oct. 19, 2023 Office Action issued in Chinese Patent Application No. 202080096822.8. [cited by applicant]
Mar. 8, 2024 Office Action issued in Chinese Patent Application No. 202080096822.8. [cited by applicant]