Method for operating a magnetic switching element

Patent metadata

Field	Value
Publication number	US-9624884-B2
Application number	US-201113883191-A
Country	US
Kind code	B2
Filing date	Oct 12, 2011
Priority date	Nov 3, 2010
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

In a method for operating a magnetic switching element, at least one connection of at least one sensor device is connected to at least one connection of a coil of the magnetic switching element, and at least one measuring state is established in which the at least one connection of the coil is largely at least temporarily decoupled from a ground, a voltage source, and/or a current source activating the coil, and at least one auxiliary voltage and/or at least one auxiliary current is/are applied to the at least one connection of the coil in the measuring state, and at least one sensor signal is ascertained from at least one electrical potential, at least one potential difference, and/or at least one current flowing at the connections of the coil.

First claim

What is claimed is:

1. A method for operating a magnetic switching element, comprising:
connecting a coil of the magnetic switching element to a control device at first connection points;
connecting at least one sensor to each of at least one of the first connection points; and
in a measuring state:
decoupling, by the control device, the first connection points from a voltage source voltage that activates the coil;
applying, by the control device, at least one of an auxiliary voltage and an auxiliary current to the first connection points, wherein an electrical potential at the at least one of the first connection points is affected by (a) the at least one of the auxiliary voltage and auxiliary current applied by the control device and (b) a signal output by the at least one sensor; and
ascertaining the signal output by the at least one sensor by measuring at least one of (i) the electrical potential at the at least one of the first connection points, (ii) a potential difference involving the electrical potential at the at least one of the first connection points, and (iii) a current flowing through the at least one of the first connection points.

2. The method as recited in claim 1 , wherein at least one control line connected to the first connection points in the at least one measuring state is used to (i) apply the at least one of the auxiliary voltage and the auxiliary current to the first connection points, and (ii) transmit the at least one of the electrical potential at the at least one of the first connection points and the current flowing through the at least one of the first connection points in a direction of the voltage source.

3. The method as recited in claim 1 , wherein:
the magnetic switching element is a servo valve of a fuel injector of an internal combustion engine or a component of the servo valve;
the sensor signal is formed in response to a pressure prevailing in a hydraulic control chamber; and
at least one of an opening and closing point in time of a valve element of the fuel injector is ascertained from the ascertained pressure prevailing in the hydraulic control chamber.

4. The method as recited in claim 1 , wherein the magnetic switching element is operated periodically in the following manner:
in a first phase, the magnetic switching element is energized with the aid of a driver circuit of the control device such that the coil of the magnetic switching element is at least intermittently connected to the voltage source voltage that activates the coil;
in a subsequent second phase, the voltage source voltage that activates the coil is subsequently disconnected from the coil of the magnetic switching element, and a residual current flowing through the coil is substantially extinguished with the aid of electrical switching elements; and
in a subsequent third phase, the measuring state is established and the sensor signal is ascertained.

5. An electrical circuit for operating a magnetic switching element, comprising:
for each of at least one of first connection points, at least one sensor connected the respective connection point;
a control device that is connected to a coil of the magnetic switching element at the first connection points and that is configured to, in a measuring state:
decouple the first connection points from a voltage source voltage that activates the coil; and
apply at least one of an auxiliary voltage and an auxiliary current to the first connection points, wherein an electrical potential at the at least one of the first connection points is affected by (a) the at least one of the auxiliary voltage and auxiliary current applied by the control device and (b) a signal output by the at least one sensor; and

a measurement circuit that is configured to, in the measuring state, ascertain the signal output by the at least one sensor by measuring at least one of (i) the electrical potential at the at least one of the first connection points, (ii) a potential difference involving the electrical potential at the at least one of the first connection points, and (iii) a current flowing through the at least one of the first connection points.

6. The electrical circuit as recited in claim 5 , wherein the auxiliary voltage is derived from an output voltage of a DC/DC converter.

7. The electrical circuit as recited in claim 5 , wherein the at least one sensor includes an electrical component or an electrical component group.

8. The electrical circuit as recited in claim 7 , wherein the at least one sensor includes a force-sensitive transducer.

9. The electrical circuit as recited in claim 8 , wherein the force-sensitive transducer is a piezoelectric element.

10. A device, comprising:
a processor; and
a non-transitory computer-readable data storage medium storing a computer program having program codes that are executable by the processor and that, when executed by the processor, cause the processor to perform a method for operating a magnetic switching element, the method comprising:
connecting a coil of the magnetic switching element to a control device at first connection points;
connecting at least one sensor to each of at least one of the first connection points; and
in a measuring state:
decoupling, by the control device, the first connection points from a voltage source voltage that activates the coil;
applying, by the control device, at least one of an auxiliary voltage and an auxiliary current to the first connection points, wherein an electrical potential at the at least one of the first connection points is affected by (a) the at least one of the auxiliary voltage and auxiliary current applied by the control device and (b) a signal output by the at least one sensor; and
ascertaining the signal output by the at least one sensor by measuring at least one of (i) the electrical potential at the at least one of the first connection points, (ii) a potential difference involving the electrical potential at the at least one of the first connection points, and (iii) a current flowing through the at least one of the first connection points.

Assignees

• Rodriguez-Amaya Nestor
• Ruthardt Siegfried
• Rapp Holger
• Stoecklein Wolfgang
• Berghaenel Bernd
• Beier Marco
• Bosch Gmbh Robert

Inventors

• Rodriguez-Amaya Nestor
• Ruthardt Siegfried
• Rapp Holger
• Stoecklein Wolfgang
• Berghaenel Bernd
• Beier Marco

Classifications

• F02D41/20 Primary

  Output circuits, e.g. for controlling currents in command coils · CPC title

• F02D2041/2055

  with means for determining actual opening or closing time · CPC title

• H01F2007/185

  with armature position measurement · CPC title

• F02D41/247

  Behaviour for small quantities · CPC title

• F02D41/2438

  Active learning methods · CPC title