Electric power tool

Patent metadata

Field	Value
Publication number	US-12030170-B2
Application number	US-202017640643-A
Country	US
Kind code	B2
Filing date	Aug 6, 2020
Priority date	Sep 6, 2019
Publication date	Jul 9, 2024
Grant date	Jul 9, 2024

Abstract

The disclosure discloses an electric power tool. The electric power tool may include a motor, a power transmission mechanism connected to the motor, a housing that houses the motor and the power transmission mechanism, an end tool holder to which an end tool is configured to be attached and from which the end tool is configured to be detached, and connected to the power transmission mechanism, and a handle attached to the housing. The electric power tool may be configured to prohibit rotation of the motor when a user is not gripping the handle.

First claim

What is claimed is:

1. An electric power tool comprising:
a motor;
a power transmission mechanism connected to the motor;
a housing that houses the motor and the power transmission mechanism;
an end tool holder to which an end tool is configured to be attached and from which the end tool is configured to be detached, and connected to the power transmission mechanism;
a handle attached to the housing;
an intermediate member configured to move between a first position and a second position;
a control unit configured to control an operation of the motor; and
a detection sensor connected to the control unit and configured to detect a movement of the intermediate member,
wherein the intermediate member is in the first position when the user is not gripping the handle, and moves from the first position to the second position in response to a manipulation performed by the user while the user is gripping the handle,
the detection sensor is disposed inside the housing, and
the control unit is configured to prohibit the rotation of the motor when the detection sensor does not detect that the intermediate member has moved from the first position to the second position, and allow the rotation of the motor when the detection sensor detects that the intermediate member has moved from the first position to the second position.

2. The electric power tool according to claim 1 , wherein the detection sensor is a non-contact type detection sensor.

3. The electric power tool according to claim 2 , wherein the detection sensor and the intermediate member are disposed in the housing, and
the handle further comprises a relay member that moves the intermediate member from the first position to the second position in conjunction with a manipulation performed by the user while the user is gripping the handle.

4. The electric power tool according to claim 2 , wherein the detection sensor comprises a light emitting element and a light receiving element corresponding to the light emitting element.

5. The electric power tool according to claim 4 , wherein the light emitting element and the light receiving element are arranged to face each other;
the intermediate member is positioned between the light emitting element and the light receiving element when the intermediate member is in one of the first position and the second position, and
the intermediate member is not positioned between the light emitting element and the light receiving element when the intermediate member is in the other of the first position and the second position.

6. The electric power tool according to claim 4 , wherein
the light emitting element and the light receiving element are arranged to be oriented in a same direction,
light emitted by the light emitting element is reflected by the intermediate member and received by the light receiving element when the intermediate member is in one of the first position and the second position, and
the light emitted by the light emitting element is not received by the light receiving element when the intermediate member is in the other of the first position and the second position.

7. The electric power tool according to claim 1 , wherein the detection sensor is a contact type detection sensor,
the intermediate member presses the detection sensor when the intermediate member is in one of the first position and the second position, and
the intermediate member does not press the detection sensor when the intermediate member is in the other of the first position and the second position.

8. The electric power tool according to claim 7 , wherein
the intermediate member is swingably supported by the housing,
the handle is fixed to the intermediate member, and
the intermediate member swings from the first position to the second position by the user swinging the handle with respect to the housing.

9. The electric power tool according to claim 7 , wherein
the intermediate member is slidably supported by the housing,
the electric power tool further comprises:
a relay member swingably supported by the housing; and
a bias member that biases the intermediate member in a direction to press the intermediate member against the relay member,
the handle is fixed to the relay member, and
the relay member swings and the intermediate member slides from the first position to the second position by the user swinging the handle with respect to the housing.

10. The electric power tool according to claim 9 , wherein the relay member is swingably supported by the housing about a first swing axis and a second swing axis orthogonal to the first swing axis.

11. The electric power tool according to claim 1 , wherein
the handle comprises:
a handle body; and
a handle manipulation member disposed on the handle body and configured to be manipulated by the user, and
the intermediate member moves from the first position to the second position in conjunction with a manipulation to the handle manipulation member by the user.

12. The electric power tool according to claim 11 , wherein one of the handle and the housing comprises an insertion pin having a non-circular shape;
the other of the handle and the housing comprises an insertion hole that accepts the insertion pin such that the insertion pin is unable to rotate, and
the electric power tool further comprises a lock member that prevents the insertion pin from coming out of the insertion hole.

13. The electric power tool according to claim 1 , further comprising a battery detachably attached to the housing and configured to supply power to the motor.

14. The electric power tool according to claim 1 , that is configured to use a grinding wheel as the end tool and configured to function as a grinder.

15. The electric power tool according to claim 1 , wherein
the housing includes a grip, and
the electric power tool is configured to be used by the user with one hand gripping the grip and the other hand gripping the handle.

16. An electric power tool comprising:
a motor;
a power transmission mechanism connected to the motor;
a housing that houses the motor and the power transmission mechanism;
an end tool holder to which an end tool is configured to be attached and from which the end tool is configured to be detached, and connected to the power transmission mechanism;
a handle attached to the housing;
an intermediate member configured to move between a first position and a second position; and
a main manipulation member configured to move between an on position and an off position according to a manipulation by the user,
wherein the electric power tool is configured to rotate the motor when the main manipulation member is in the on position and stop the rotation of the motor when the main manipulation member is in the off position,
the intermediate member is in the first position when the user is not gripping the handle, and moves from the first position to the second position in response to a manipulation performed by the user while the user is gripping the handle, and
a movement of the main manipulation member from the off position to the on position is prohibited when the intermediate member is in the first position and the movement of the main manipulation member from the off position to the on position is allowed when the intermediate member is in the second position.

Assignees

• Makita Corp

Inventors

• Kaneko Hiroki
• Mizutani Akira
• Otani Ryosuke
• Yamaji Shunpei
• Ishikawa Junya
• Saito Fumiyoshi

Classifications

• B24B47/12

  by mechanical gearing or electric power (B24B47/16 takes precedence) · CPC title

• B25F5/026 Primary

  in the form of an auxiliary handle (B25F5/024 takes precedence) · CPC title

• B24B47/26

  Accessories, e.g. stops · CPC title

• B25F5/00

  Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for · CPC title

• B24B23/028 Primary

  Angle tools · CPC title