POWER TOOL

• US 20140083375A1
• Filed: 09/24/2013
• Published: 03/27/2014
• Est. Priority Date: 09/26/2012
• Status: Abandoned Application

• Current Assignee: Makita Corporation
• Original Assignee: Makita Corporation
• Inventors: KAWASHIMA, Hideo, HIRABAYASHI, Shinji, HAYASHI, Noriaki
• Application Number:
  US14/034,980
• Publication Number:
  US 20140083375A1
• Time in Patent Office: Days
• US Class Current: 123/2
• CPC Class Codes: B60K 6/485 Motor-assist type
• CPC Class Codes: F02B 63/02 for hand-held tools
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A brush cutter as a power tool includes an engine, an electric motor, a driving shaft capable of driving a tool and a battery which provides current to the electric motor. The brush cutter is adapted to drive the tool in a hybrid driving mode in which both the engine and the electric motor drive the tool. Further, the engine is arranged between the electric motor and the driving shaft.

Claims

1. A power tool which drives a tool and perfumes an operation, comprising:

an engine,

a motor,

a driving shaft capable of driving the tool, and

a battery which provides current to the motor,

wherein the power tool drives the tool in a hybrid driving mode in which both the engine and the motor drive the tool,

and wherein the engine is arranged between the motor and the driving shaft.

2. The power tool according to claim 1, wherein the motor biases a piston of the engine when the piston moves toward a top dead point from a bottom dead point during one engine cycle.

3. The power tool according to claim 2, wherein the motor functions as a generator when the piston moves toward the bottom dead point from the top dead point during one engine cycle.

4. The power tool according to claim 1, wherein the motor functions as a generator, and wherein the battery is charged by electricity generated by the motor driven as the generator.

5. The power tool according to claim 1, wherein the motor functions as a starter motor when starting the engine.

6. The power tool according to claim 1, further comprising a recoil starter which is connected to the motor,

wherein the recoil starter starts the engine via the motor.

7. The power tool according to claim 1, wherein the motor is connected to an output shaft of the engine.

8. The power tool according to claim 7, wherein the motor has a stator and a rotor, and the motor is formed as an outer rotor motor in which the rotor is arranged rotatably outside the stator,

and wherein the rotor is connected to the output shaft of the engine.

9. The power tool according to claim 1, comprising a body portion which houses the engine, and a connecting portion which connects the body portion and the battery,

wherein the connecting portion has a holding region which is held by a user.

15. The power tool according to claim 1, comprising a body portion which houses the engine

wherein the body portion has an exhaust opening through which an exhaust air of the engine is exhausted,

and wherein the battery is arranged at the body portion other than on a normal line of a plane defined by an opening edge of the exhaust opening, the normal line extending from the plane outward opposite to the engine.

21. The power tool according to claim 1, comprising a battery cover which covers the battery.

10. A power tool which drives a tool and performs an operation, comprising:

an engine capable of driving the tool,

a motor,

a body portion which houses the engine,

a battery which provides current to the motor, and

a connecting portion which connects the body portion and the battery,

wherein the connecting portion has a holding region which is held by a user.

11. The power tool according to claim 10, wherein the connecting portion includes a first portion which connects the body portion and the battery, and a second portion which is other than the first portion, the second portion connecting the body portion and the battery,

and wherein the holding region is provided on at least one of the first portion and the second portion.

12. The power tool according to claim 10, wherein the battery is connected to a distal end region of the connecting portion, the distal end region being the most distant from the body portion.

13. The power tool according to claim 10, wherein the connecting portion includes a battery attached portion to which the battery is attached,

and wherein the battery is detachably attached to the battery attached portion.

14. The power tool according to claim 10, comprising a controller which controls the motor,

wherein the controller is arranged at the connecting portion.

16. A power tool which is adapted to drive a tool and perform an operation, comprising:

an engine,

a motor,

a driving shaft capable of driving the tool,

a body portion which houses the engine, and

a battery which provides current to the motor,

wherein the body portion has an exhaust opening through which exhaust air of the engine is exhausted,

and wherein the battery is arranged at the body portion other than on a normal line of a plane defined by an opening edge of the exhaust opening, the normal line extending from the plane outward opposite to the engine.

17. The power tool according to claim 16, wherein an exhausting direction in which the exhaust air is exhausted is opposite to a direction in which the driving shaft protrudes from the body portion,

and wherein the battery is arranged at the body portion so that the battery is closer to the driving shaft than the exhaust opening.

18. The power tool according to claim 16, wherein the battery is arranged at a region which overlaps with the driving shaft, when seen in a direction in which a piston slides within a cylinder of the engine.

19. The power tool according to claim 16, wherein the battery is detachably attached to the body portion.

20. The power tool according to claim 16, comprising a controller which controls the motor,

wherein the controller is arranged at the battery side of the body portion, which is across the engine from the exhaust opening.