Method and device for driving a load

• US 5,955,792 A
• Filed: 11/10/1997
• Issued: 09/21/1999
• Est. Priority Date: 11/08/1996
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Fischer, Werner, Luebbert, Birte
• Primary Examiner(s): PALADINI, ALBERT WILLIAM
• Application Number:
  US08/966,512
• Time in Patent Office: 680 Days
• Field of Search: 307/87, 307/131, 327/108, 327/110, 327/139, 361/93, 361/143, 361/152, 361/31, 323/285
• US Class Current: 307/87
• CPC Class Codes: H01F 7/1844 Monitoring or fail-safe circuits for relays H01H47/002

Abstract

A method and a device for driving a load, particularly an electromagnetic load. The current flowing through the load is detected, and is controlled by a control device connected in series to the load. During a first phase, in addition to the control device, a first switching device is driven that is disposed parallel to the control device. During a third phase, in addition to the control device, a second switching device is driven that is disposed parallel to the control device.

Claims

1. A method for driving a load, comprising the steps of:

during a first phase of a three-phase driving process, driving a control device and a first switching device disposed parallel to the control device being controlled as a function of a current flowing through the load;

performing a second phase of the three-phase driving process; and

during a third phase of the three-phase driving process, driving the control device and a second switching device disposed parallel to the control device.

2. The method according to claim 1, wherein the load is an electromagnetic load.

3. The method according to claim 1, further comprising the step of detecting the current flowing through the load.

4. The method according to claim 1, wherein the control device is controlled as a function of a comparison between the current flowing through the load and a desired current.

5. The method according to claim 1, wherein the current flowing through the load is adjusted to a first setpoint value during the first phase, to a second setpoint value during a second phase, and to a third setpoint value during the third phase.

6. The method according to claim 5, wherein, during the first phase, before a driving of the load, a position of the load remains constant and a large current component flows through the first switching device.

7. The method according to claim 5, wherein, during the second phase, at a start of a driving of the load, a position of the load changes and a large current component flows through the control device.

8. The method according to claim 5, wherein, during the third phase, a position of the load is maintained and a large current component flows through the second switching device.

9. A device for driving a load, comprising:

means for detecting a current flowing through the load;

a control device connected in series with the load, the control device being controlled as a function of the current flowing through the load;

first and second switching devices disposed parallel to the control device; and

means for driving the control device and the first switching device during a first phase of a three-phase driving process, and for driving the control device and the second switching device during a third phase of the three-phase driving process, the three-phase driving process including a second phase.

10. The device according to claim 9, wherein the load is an electromagnetic load.