Electric working machine

Patent metadata

Field	Value
Publication number	US-2020260644-A1
Application number	US-202016787140-A
Country	US
Kind code	A1
Filing date	Feb 11, 2020
Priority date	Feb 18, 2019
Publication date	Aug 20, 2020
Grant date	—

Abstract

An electric working machine includes an attachment portion, a motor, and a controller. Multiple types of tip tools are alternatively attached to the attachment portion. The motor drives the tip tool attached to the attachment portion. The controller has first start control and second start control. The controller is configured to execute the first start control so as to determine the type of the tip tool when not having tool type information, and configured to execute the second start control when having the tool type information.

First claim

What is claimed is:

1 . An electric working machine comprising:
an attachment portion to which multiple types of tip tools are alternatively attached; a motor that drives the tip tool attached to the attachment portion; and a controller that has first start control in which the motor is started and controlled with a first parameter, and second start control in which the motor is started and controlled with a second parameter, the second parameter being different from the first parameter, the controller being configured to execute the first start control so as to determine the type of the tip tool in response to not having tool type information on the tip tool, and the controller being configured to execute the second start control in response to having the tool type information.

2 . The electric working machine according to claim 1 ,
wherein the controller is configured to detect a determination parameter set in advance to determine the type of the tip tool, and determine the type of the tip tool by determining whether the determination parameter exceeds a preset tip tool determination value during execution of the first start control.

3 . The electric working machine according to claim 1 , further comprising:
a rotation speed manipulator configured to be manipulated by an operator to set rotation speed of the motor, wherein, in the first start control, manipulation performed on the rotation speed manipulator is disabled.

4 . The electric working machine according to claim 1 ,
wherein an increase per unit time in rotation speed of the motor is set as an increase in rotation speed, wherein the increase in rotation speed at the time of rotating the motor during execution of the first start control by the controller is set as an increase in first rotation speed, wherein the increase in rotation speed at the time of rotating the motor during execution of the second start control by the controller is set as an increase in second rotation speed, and wherein the increase in first rotation speed is larger than the increase in second rotation speed.

5 . The electric working machine according to claim 1 , further comprising:
a driving operating portion configured to be manipulated by an operator to switch between driving and stopping the motor, wherein, in the first start control, manipulation on other portions than the driving operating portion is disabled.

6 . The electric working machine according to claim 1 ,
wherein the electric working machine is a grass cutter.

7 . The electric working machine according to claim 1 ,
wherein a target value of rotation speed of the motor is set as target rotation speed, wherein the target rotation speed at the time of rotating the motor during execution of the first start control by the controller is set as first target rotation speed, wherein the target rotation speed at the time of rotating the motor during execution of the second start control by the controller is set as second target rotation speed, and wherein a maximum value of the first target rotation speed is smaller than a maximum value of the second target rotation speed.

8 . The electric working machine according to claim 2 ,
wherein the determination parameter is one of electric current flowing to the motor, an increase rate in the electric current, rotation speed of the motor, an increase rate in the rotation speed, a duty ratio of a PWM signal for drive control of the motor, or vibration.

9 . An electric working machine comprising:
an attachment portion to which multiple types of tip tools are alternatively attached; a motor that drives the tip tool attached to the attachment portion; and a controller that has first start control in which the motor is started and controlled with a first parameter, and second start control in which the motor is started and controlled with a second parameter, the second parameter being different from the first parameter, the controller being configured to execute the first start control at initial startup following power supply so as to determine the type of a tip tool, and the controller being configured to execute the second start control at startup after execution of the first start control following the power supply.

10 . The electric working machine according to claim 9 ,
wherein the controller is configured to detect a determination parameter set in advance to determine the type of the tip tool, and determine the type of the tip tool by determining whether the determination parameter exceeds a preset tip tool determination value during execution of the first start control.

11 . The electric working machine according to claim 9 , further comprising:
a rotation speed manipulator configured to be manipulated by an operator to set rotation speed of the motor, wherein, in the first start control, manipulation performed on the rotation speed manipulator is disabled.

12 . The electric working machine according to claim 9 ,
wherein an increase per unit time in rotation speed of the motor is set as an increase in rotation speed, wherein the increase in rotation speed at the time of rotating the motor during execution of the first start control by the controller is set as an increase in first rotation speed, wherein the increase in rotation speed at the time of rotating the motor during execution of the second start control by the controller is set as an increase in second rotation speed, and wherein the increase in first rotation speed is larger than the increase in second rotation speed.

13 . The electric working machine according to claim 9 , further comprising:
a driving operating portion configured to be manipulated by an operator to switch between driving and stopping the motor, wherein, in the first start control, manipulation on other portions than the driving operating portion is disabled.

14 . The electric working machine according to claim 9 ,
wherein the electric working machine is a grass cutter.

15 . The electric working machine according to claim 9 ,
wherein a target value of rotation speed of the motor is set as target rotation speed, wherein the target rotation speed at the time of rotating the motor during execution of the first start control by the controller is set as first target rotation speed, wherein the target rotation speed at the time of rotating the motor during execution of the second start control by the controller is set as second target rotation speed, and wherein a maximum value of the first target rotation speed is smaller than a maximum value of the second target rotation speed.

16 . The electric working machine according to claim 10 ,
wherein the determination parameter is one of electric current flowing to the motor, an increase rate in the electric current, rotation speed of the motor, an increase rate in the rotation speed, a duty ratio of a PWM signal for drive control of the motor, or vibration.

Assignees

• Makita Corp

Inventors

• Ichikawa Yoshitaka

Classifications

• B25F5/00

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

• H02P29/00 Primary

  Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors (arrangements for starting electric motors H02P1/00; arrangements for stopping or slowing electric motors H02P3/00; control of motors that can be connected to two or more different electric power supplies H02P4/00; regulating or controlling the speed or torque of two or more electric motors H02P5/00; vector control H02P21/00) · CPC title

• H02P29/40

  Regulating or controlling the amount of current drawn or delivered by the motor for controlling the mechanical load · CPC title

• A01D34/78 Primary

  electric · CPC title

• A01D34/90

  for carrying by the operator · CPC title