Rotation control device, rotation control method and construction machine

• US 7,619,378 B2
• Filed: 07/04/2005
• Issued: 11/17/2009
• Est. Priority Date: 07/05/2004
• Status: Expired due to Fees

• Current Assignee: Komatsu Ltd.
• Original Assignee: Komatsu Ltd.
• Inventors: Inoue, Hiroaki, Morinaga, Jun
• Primary Examiner(s): Ro; Bentsu
• Application Number:
  US11/631,433
• Publication Number:
  US 20080018271A1
• Time in Patent Office: 1,597 Days
• Field of Search: 318/139, 318/268, 123/361
• US Class Current: 318/139
• CPC Class Codes: E02F 9/123 Drives or control devices specially adapted therefor E02F9/125 and E02F9/128 take precedence

Abstract

A control device 50 of an electric rotary excavator generates a rotation speed coefficient in accordance with a setting condition of a fuel dial 13 and a selection condition of a mode selection switch 14 and changes a value of a target speed command value based on the rotation speed coefficient to change a rotation speed of a rotary body 4. Accordingly, when the engine speed becomes low through operation of the fuel dial 13 or the mode selection switch 14, the rotation speed of the rotary body 4 can be decreased accordingly, while when the engine speed becomes high, the rotation speed can be increased accordingly. Therefore, the operation feeling substantially similar to a conventional arrangement for hydraulically rotating the rotary body 4 can be obtained, so that the operator is not confused when the operator shifts excavators from the conventional hydraulic excavator to the electric rotary excavator.

Claims

1. A rotation control device for an electric motor that drives a rotary body provided with a work machine of a construction machine, the electric motor driving the rotary body in accordance with an operation of a rotation lever, the rotation control device comprising:

a target speed command generating unit that generates a target speed command value of the electric motor in accordance with the operation of the rotation lever,

wherein the target speed command generating unit changes the target speed command value in accordance with at least one of;

a setting condition of a fuel supply setting means for setting an engine speed of an engine that is used in conjunction with the electric motor;

an operation amount of a work machine lever for operating the work machine that is driven by the engine; and

a selection condition of a work mode selecting means for selecting a work mode of a work performed using the work machine to set a fuel supply to the engine.

2. A rotation control method for an electric motor that drives a rotary body provided with a work machine of a construction machine, the electric motor driving the rotary body in accordance with an operation of a rotation lever, the rotation control method comprising:

generating a target speed command value of the electric motor in accordance with the operation of the rotation lever; and

changing the target speed command value of the electric motor in accordance with at least one of;

a setting condition of a fuel supply setting means for setting an engine speed of an engine that is used in conjunction with the electric motor;

an operation amount of a work machine lever for operating the work machine that is driven by the engine; and

a selection condition of a work mode selecting means for selecting a work mode of a work performed using the work machine to set a fuel supply to the engine.

3. A construction machine, comprising:

a rotary body provided with a work machine;

a rotation lever that is actuated to cause rotation of the rotary body;

an electric motor that drives the rotary body in accordance with operation of the rotation lever; and

a rotation control device for controlling the electric motor,

wherein the rotation control device changes a target speed command value of the electric motor in accordance with at least one of;

a setting condition of a fuel supply setting means for setting an engine speed of an engine that is used in conjunction with the electric motor;

an operation amount of a work machine lever for operating the work machine that is driven by the engine; and

a selection condition of a work mode selecting means for selecting a work mode of a work performed using the work machine to set a fuel supply to the engine.