Control Device for an Electric Actuator

• US 20130073111A1
• Filed: 05/11/2011
• Published: 03/21/2013
• Est. Priority Date: 05/20/2010
• Status: Active Grant

• Current Assignee: Komatsu Ltd.
• Original Assignee: Komatsu Ltd.
• Inventors: Kawaguchi, Tadashi, Morinaga, Jun, Take, Hiroaki
• Granted Patent: US 9,617,713 B2
• Time in Patent Office: Days
• US Class Current: 700/301
• CPC Class Codes: E02F 9/123 Drives or control devices specially adapted therefor E02F9/125 and E02F9/128 take precedence
• CPC Class Codes: E02F 9/2095 Control of electric, electro-mechanical or mechanical equipment not otherwise provided for, e.g. ventilators, electro-driven fans control of hydraulic driven equipment E02F9/22
• CPC Class Codes: E02F 9/2221 Control of flow rate; Load sensing arrangements E02F9/2203 take precedence over E02F9/2221
• CPC Class Codes: F15B 2211/20553 with pilot circuit, e.g. for controlling a swash plate
• CPC Class Codes: F15B 2211/275 Control of the prime mover, e.g. hydraulic control
• CPC Class Codes: F15B 2211/50527 using cross-pressure relief valves
• CPC Class Codes: F15B 2211/6316 the pressure being a pilot pressure
• CPC Class Codes: F15B 2211/7058 Rotary output members

Abstract

A control device of an electric actuator adapted to perform a forward-reverse movement includes a control unit adapted to be operated in a forward direction or a reverse direction in accordance with the forward-reverse movement of the electric actuator. It also includes a pilot circuit, which is connected to the control unit and which generates a forward pilot pressure or a reverse pilot pressure in accordance with the forward operation or the reverse operation of the control unit. The control device has a differential pressure acquiring unit that acquires a differential pressure between a pilot pressure corresponding to an operation direction of the control unit and a pilot pressure, in a direction opposite to the operation direction, and it has a control command generator that generates a control command for controlling the electric actuator based on the differential pressure acquired by the differential pressure acquiring unit. The control device includes a drive controller for controlling a drive of the electric actuator based on the generated control command.

Claims

1. A control device of an electric actuator that is adapted to perform a forward-reverse movement, the control device comprising:

a control unit that is adapted to be operated in a forward direction or a reverse direction in accordance with the forward-reverse movement of the electric actuator;

a pilot circuit that is connected with the control unit, the pilot circuit generating a forward pilot pressure or a reverse pilot pressure in accordance with the forward operation or the reverse operation of the control unit;

a differential pressure acquiring unit that acquires a differential pressure between a pilot pressure corresponding to a operation direction of the control unit and a pilot pressure in a direction opposite to the operation direction;

a control command generator that generates a control command to the electric actuator based on the differential pressure acquired by the differential pressure acquiring unit; and

a drive controller that controls a drive of the electric actuator based on the control command generated by the control command generator.

2. The control device according to claim 1, wherein

the differential pressure acquiring unit comprises:

a forward pressure detector that detects the forward pilot pressure of the pilot circuit;

a reverse pressure detector that detects the reverse pilot pressure of the pilot circuit; and

a differential pressure calculating section that calculates a differential pressure between the forward pilot pressure detected by the forward pressure detector and the reverse pilot pressure detected by the reverse pressure detector.