Operation circuit for a work vehicle

• US 20050122068A1
• Filed: 11/29/2004
• Published: 06/09/2005
• Est. Priority Date: 12/04/2003
• Status: Active Grant

• Current Assignee: Hitachi Construction Machinery Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi Construction Machinery Company Limited (Hitachi, Ltd.)
• Inventors: Ichimura, Kazuhiro, Kodaka, Katsuaki
• Granted Patent: US 7,518,322 B2
• Time in Patent Office: Days
• US Class Current: 318/34
• CPC Class Codes: E02F 9/2025 Particular purposes of control systems not otherwise provided for E02F3/16, E02F3/26, sub-groups of E02F3/43, E02F3/651, sub-groups of E02F3/84, E02F3/907, E02F5/145 take precedence

Abstract

An operation circuit for a work vehicle drives an electromagnetic actuator by generating an operation signal corresponding to a switch operation and drives a work actuator in response to the drive of the electromagnetic actuator. By installing a specific detachable electric circuit unit in a first operation circuit that generates a first operation signal in response to an operation of a specific switch, the first operation circuit can be modified to a second operation circuit that generates a second operation signal different from the first operation signal in response to an operation of the same switch.

Claims

1. An operation circuit for a work vehicle, which drives a work actuator in response to drive of an electromagnetic actuator driven with an operation signal generated in response to a switch operation, wherein:

a first operation circuit that generates a first operation signal in response to an operation of a specific switch can be modified to a second operation circuit that generates a second operation signal different from the first operation signal in response to an operation of the specific switch by installing a specific detachable electric circuit unit at the first operation circuit via connectors.

2. An operation circuit for a work vehicle according to claim 1, wherein:

the first operation circuit is modified to the second operation circuit by replacing an electric circuit unit included in the first operation circuit which is disposed between the specific switch and the electromagnetic actuator, with the specific detachable electric circuit unit.

3. An operation circuit for a work vehicle according to claim 1, wherein:

the electric circuit unit includes a relay circuit.

4. An operation circuit for a work vehicle according to claim 1, wherein:

the first operation signal is an operation signal in response to which a drive command for driving the work actuator is output while the switch operation is sustained, and the second operation signal is an operation signal in response to which the drive command for driving the work actuator is continuously output once the switch operation is performed even if the switch operation stops.

5. An operation circuit for a work vehicle according to claim 1, wherein:

the first operation signal is an operation signal used to issue a command for a specific operation of the work actuator in response to the switch operation, and the second operation signal is an operation signal used to issue a command for another operation of the work actuator in addition to the specific operation of the work actuator.

6. An operation circuit for a work vehicle according to claim 1, wherein:

the second operation circuit includes a selector switch operated to select drive of a single work actuator among a plurality of work actuators; and

the first operation signal is an operation signal in response to which a drive command for driving a specific work actuator is output and the second operation signal is an operation signal in response to which a drive command for driving a work actuator selected with the selector switch is output.

7. An operation circuit for a work vehicle, comprising:

a switch device;

an electromagnetic actuator driven in response to a command issued through the switch device;

an electric circuit unit disposed between the switch device and the electromagnetic actuator, which controls drive of the electromagnetic actuator in response to a command issued through the switch device; and

a connector device that individually connects the switch device with the electric circuit unit and the electric circuit unit with the electromagnetic actuator, wherein;

a mode in which the electromagnetic actuator is driven in response to the command from the switch device is modified by replacing the electric circuit unit with another electric circuit unit via the connector device.