ELECTRIC POWER TOOL

• US 20190070705A1
• Filed: 08/28/2018
• Published: 03/07/2019
• Est. Priority Date: 09/05/2017
• Status: Active Grant

• Current Assignee: Makita Corporation
• Original Assignee: Makita Corporation
• Inventors: ISHIKAWA, Junya
• Granted Patent: US 11,000,933 B2
• Time in Patent Office: Days
• CPC Class Codes: B24B 23/028 Angle tools
• CPC Class Codes: B24B 23/03 the tool being driven in a combined movement
• CPC Class Codes: B24B 27/0076 grinding machines comprising two or more grinding tools
• CPC Class Codes: B24B 41/007 Weight compensation; Temperature compensation; Vibration damping
• CPC Class Codes: B24D 13/14 acting by the front face
• CPC Class Codes: B24D 13/147 comprising assemblies of felted or spongy material; comprising pads surrounded by a flexible material
• CPC Class Codes: B24D 9/08 Circular back-plates for carrying flexible material
• CPC Class Codes: B25F 5/008 Cooling means
• CPC Class Codes: B25F 5/02 Construction of casings, bodies or handles B25F5/006, B25F5/008 take precedence
• CPC Class Codes: B60S 3/06 with rotary bodies contacting the vehicle hand-held B60S3/048
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 50/247 specially adapted for portable devices, e.g. mobile phones, computers, hand tools or pacemakers
• CPC Class Codes: H02K 7/145 Hand-held machine tool
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

In an angle electric power tool 1 in which an output axis P intersects and is orthogonal to a motor axis J, a battery attachment portion 40 is provided to the rear of a grip 30 so as to extend in the rearward direction and a battery pack 50 is configured to be attached to an upper surface of said battery attachment portion 40. Because of this configuration, the battery pack 50 does not directly come into contact with a working surface W, thereby preventing flaws and scratches on the working surface W.

Claims

1. An electric power tool, comprising:

a tool main body that houses an electric motor in a main body housing;

an output shaft that protrudes from a lower portion of the tool main body and extends in an up-to-down direction; and

a battery attachment portion for attaching a slide-attachment type battery pack that supplies power to the electric motor, the battery attachment portion being disposed at the rear portion of the tool main body, wherein,

the battery pack is attached to an upper surface of the battery attachment portion.

2. The electric power tool according to claim 1, wherein the battery pack is attached to the upper surface of the battery attachment portion such that its shortest dimension is aligned with the up-to-down direction.

3. The electric power tool according to claim 1, wherein an upper end of the battery attachment portion region protrudes upward higher than the upper surface of the battery pack that is attached to the battery attachment portion.

4. The electric power tool according to claim 1, wherein an elastic member is disposed on the lower surface of the battery attachment portion.

7. The electric power tool according to claim 3, wherein an elastic member is disposed on the upper end of the battery attachment portion region.

8. The electric power tool according to claim 1, further comprising a leg used for placing the electric power tool upside down that is formed at the top of the main body housing, the leg being made of an elastic member.

5. An electric power tool, comprising:

a tool main body that houses an electric motor in a main body housing;

an output shaft that protrudes from a lower portion of the tool main body and extends in an up-to-down direction; and

a battery attachment portion for attaching a slide-attachment type battery pack that supplies power to the electric motor, the battery attachment portion being disposed at the rear portion of the tool main body, wherein,

an elastic member is disposed on a lower surface of the battery attachment portion.

9. The electric power tool according to claim 5, wherein the motor housed in the tool main body is a brushless motor that includes a cylindrically shaped stator that is fixed to the main body housing as well as a rotor that is rotatably supported on the inner circumferential periphery of the stator via a motor shaft, the motor shaft being orthogonal to the output shaft.

10. The electric power tool according to claim 9, wherein the motor shaft is rotatably supported by a front bearing and rear bearing at a region at the front of said shaft, and at the rear of said shaft, respectively, wherein the longitudinal axis of the motor shaft is parallel to the longitudinal axis of the tool main body, where the tool main body is formed in a roughly tubular shape.

11. The electric power tool according to claim 10, wherein a cooling fan is inserted at the front region of the motor shaft, but to the rear of the front bearing, the cooling fan fully surrounding the motor shaft and fitting with the shaft in a tight manner due to the presence of the front bearing.

12. The electric power tool according to claim 10, wherein a drive side bevel gear is provided at the front most region of the motor shaft, immediately in front of and adjacent to the front bearing, wherein the drive said bevel gear is fully surrounds and is tightly fitted on the motor shaft.

13. The electric power tool according to claim 12, wherein, a driven side bevel gear may be provided on the output shaft, such that it fully surrounds and is tightly fitted on the upper region of the output shaft, but not at the uppermost end.

14. The electric power tool according to claim 13, wherein the driven side bevel gear is present to the front of and lower than the drive side bevel gear, wherein the two gears are perpendicularly adjacent to each other such that their gears may enmesh, to enable a driving action from the motor shaft to the output shaft, wherein the output shaft may rotate by means of the bevel gear complementarily engaging with the bevel gear.

15. The electric power tool according to claim 14, wherein the output shaft may rotate about its longitudinal axis due to the driving action of the motor shaft.

16. The electric power tool according to claim 14, wherein an eccentric shaft may be integrally formed with the output shaft, extending downward from the lower surface of the output shaft, such that the longitudinal axis of the eccentric shaft may be disposed parallel to and spaced apart from the output axis by a predetermined distance in the radial direction.

17. The electric power tool according to claim 16, wherein a lower portion of the tool main body surrounding the eccentric shaft includes a cylindrical-shaped moving main body, which includes engagement teeth on its outer peripheral circumference, as well as a cylindrically shaped dependent body, wherein the moving main body may rotate within the dependent body.

18. The electric power tool according to claim 17, wherein the diameter of the dependent body is larger than the moving main body but where the moving main body may protrude lower than the dependent body, such that the lower end of the moving main body forms a tip end at the lowest point of the output shaft.

19. The electric power tool according to claim 17, wherein the dependent body may be selectively locked or unlocked, such that the moving main body may rotate around the longitudinal axis of the output shaft, or around the longitudinal axis of the output shaft as well as about the eccentric shaft, resulting in a changing position of the moving main body with respect to the dependent body.

20. The electric power tool according to claim 18, wherein a circular base portion, which may include a polishing pad which can be attached to the tip end formed by the moving main body at the lower end of the output shaft.

6. A polisher, comprising:

a tool main body that houses an electric motor in a main body housing;

an output shaft that protrudes from a lower portion of the tool main body and extends in an up-to-down direction; and

an elastic member that is disposed on at least a part of the lower portion of the tool main body.