HYDRAULIC VALVE CONTROL CIRCUIT AND METHOD FOR CHECKING THE FUNCTION OF A HYDRAULIC VALVE CONTROL CIRCUIT

• US 20090279222A1
• Filed: 05/06/2009
• Published: 11/12/2009
• Est. Priority Date: 05/09/2008
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Keller, Dieter
• Granted Patent: US 8,189,316 B2
• Time in Patent Office: Days
• US Class Current: 361/93.100
• CPC Class Codes: F15B 19/00 Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
• CPC Class Codes: F15B 20/002 Electrical failure
• CPC Class Codes: G05B 9/02 electric

Abstract

A hydraulic valve control circuit of a hydraulic valve comprises an external voltage supply, an output stage having a voltage supply input and at least one output configured to actuate an actuator of the hydraulic valve, an overcurrent protective device disposed in a path between the external voltage supply and the voltage supply input, an enable input configured to activate and deactivate the output stage, and a switch configured to connect the at least one output to a fixed potential when the output stage is deactivated.

Claims

1. A hydraulic valve control circuit of a hydraulic valve comprising:

an external voltage supply;

an output stage having a voltage supply input and at least one output configured to actuate an actuator of the hydraulic valve;

an overcurrent protective device disposed in a path between the external voltage supply and the voltage supply input;

an enable input configured to activate and deactivate the output stage; and

a switch configured to connect the at least one output to a fixed potential when the output stage is deactivated.

2. The hydraulic control circuit as recited in claim 1, wherein the overcurrent protective device includes a fusible cutout.

3. The hydraulic valve control circuit as recited in claim 1, wherein the overcurrent protective device includes a circuit breaker.

4. The hydraulic valve control circuit as recited in claim 1, further comprising a measuring circuit configured to measure a voltage at an output of the output stage.

5. The hydraulic valve control circuit as recited in claim 4, further comprising an error output indicating an error if the measuring circuit measures a potential at the output differing from the fixed potential by more than a prescribed threshold value.

6. The hydraulic valve control circuit as recited in claim 1, further comprising a second measuring circuit configured to measure a voltage at the first voltage supply input of the output stage.

7. The hydraulic valve control circuit as recited in claim 1, wherein the fixed potential is a ground potential.

8. The hydraulic valve control circuit as recited in claim 1, wherein the fixed potential is equal to the earth potential.

9. The hydraulic valve circuit as recited in claim 1, wherein the actuator actuating the hydraulic valve comprises a coil to generate a magnetic field.

10. A method to check the function of a hydraulic valve control circuit of a hydraulic control valve comprising:

providing an external voltage supply;

actuating an actuator of the hydraulic control valve using an output stage having a voltage supply input and at least one output;

disposing an overcurrent protective device in a path between the external voltage supply and the voltage supply input;

activating and deactivating the output stage using the enable input;

connecting the at least one output to a fixed potential using a switch when the output stage is deactivated;

a measuring a voltage at an output of the output stage using a measuring circuit; and

indicating an error using an error output if the potential at the output differs from the fixed potential by more than a prescribed value.

11. The method as recited in claim 10, further comprising measuring a voltage at the first voltage supply input of the output stage using a second measuring circuit.

12. The method as recited in claim 10, further comprising testing functioning of the switch.