Method for control of a proportional magnet of an electromagnetic valve

• US 20080073611A1
• Filed: 05/15/2007
• Published: 03/27/2008
• Est. Priority Date: 06/08/2006
• Status: Abandoned Application

• Current Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Wiesner, Maik, Moosmann, Markus, Mayr, Karlheinz, Kill, Walter
• Application Number:
  US11/803,477
• Publication Number:
  US 20080073611A1
• Time in Patent Office: Days
• US Class Current: 251/129.01
• CPC Class Codes: F16K 31/0655 Lift valves
• CPC Class Codes: H01F 7/1607 Armatures entering the winding
• CPC Class Codes: H01F 7/1844 Monitoring or fail-safe circuits for relays H01H47/002

Abstract

A method for control of a proportional magnet of an electromagnetic valve. Detecting valve seat bouncing by observing a control signal. Adjusting a control frequency or the alternate current amplitude to achieve the smallest hysteresis while preventing valve seat bouncing.

Claims

1-4. -4. (canceled)

5. A method of controlling a proportional magnet of an electromagnetic valve, the method comprising the steps of:

detecting seat bouncing of the valve; and

adjusting a frequency of an alternate current and an amplitude of a control current to prevent seat bouncing and minimize hysteresis.

6. The method of controlling the proportional magnet according to claim 5, further comprising the step of detecting the seat bouncing of the valve with an armature displacement sensor (7) integrated in the electromagnetic valve (1).

7. The method of controlling the proportional magnet according to claim 5, further comprising the step of detecting the seat bouncing of the valve via a counter-induction reaction produced by the seat bouncing on an actual current curve (10, 11).

8. The method of controlling the proportional magnet according to claim 7, further comprising the step of examining a first derivative of the actual current curve (8, 9) for a point of inflection with the point inflection indicating the seat bouncing.

9. A method of minimizing hysteresis during control of an electromagnetic valve by controlling a proportional magnet of the electromagnetic valve, the method comprising the steps of:

measuring a profile of an actual current flow through the electromagnetic valve;

calculating a profile of a first derivative of the actual current flow through the electromagnetic valve;

observing the profile of the first derivative of the actual current flow through the electromagnetic valve, for a point of inflection, presence of the point of inflection indicating valve seat bouncing; and

adjusting at least one of a frequency of an alternate current and an amplitude of a control current, upon the observation of valve seat bouncing, to minimize valve seat bouncing and hysteresis.