Circuit arrangement for detecting a type for a solenoid valve

Patent metadata

Field	Value
Publication number	US-9753074-B2
Application number	US-201314417014-A
Country	US
Kind code	B2
Filing date	Jul 19, 2013
Priority date	Jul 26, 2012
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A circuit arrangement for detecting a solenoid valve type in vehicles, including at least one solenoid valve in the circuit arrangement for detecting the solenoid valve type and having at least one coil winding having a resistance of the typical order of magnitude for a predetermined vehicle electrical distribution system supply voltage, a constant current source, arranged to impress a predetermined measurement current into the one coil winding of the solenoid valve, a current mirror circuit, arranged to generate a second voltage on a detection section of the circuit arrangement from a first voltage produced as a result of the impressed measurement current on the at least one coil winding of the at least one solenoid valve, in which the second voltage produced on the detection section is passed out, on the detection section, directly to a microcontroller in a control device for determining the type of solenoid valve.

First claim

The invention claimed is:

1. A circuit arrangement for detecting a type of solenoid valve in a vehicle, comprising:
at least one solenoid valve incorporated into the circuit arrangement to detect the type of the solenoid valve and having at least one coil winding having a resistance associated with a predetermined vehicle electrical distribution system supply voltage;
a constant current source arranged so as to impress a predetermined measurement current into the at least one coil winding of the at least one solenoid valve; and
a current mirror circuit arranged so as to generate a second voltage on a detection section of the circuit arrangement from a first voltage produced as a result of the impressed measurement current on the at least one coil winding of the at least one solenoid valve;
wherein the second voltage produced on the detection section is passed out, on the detection section, directly to a microcontroller in a control device for determining the type of solenoid valve.

2. The circuit arrangement of claim 1 , wherein the detected type of solenoid valve is a vehicle electrical distribution system supply voltage for which the solenoid valve is designed, wherein the vehicle electrical distribution system supply voltage includes rated voltages of 12 V and/or 24 V, and in that the solenoid valve is a pressure control solenoid valve for use in braking systems and/or traction control systems of a utility vehicle.

3. The circuit arrangement of claim 2 , wherein the resistance of the coil winding of the solenoid valve for a rated voltage of 12 V is within a single-digit resistance value range, and for a higher rated voltage, is within a two-digit to three-digit resistance value range.

4. The circuit arrangement of claim 1 , wherein the constant current source includes a transistor, which is connected to a respective resistance at the emitter, base and collector, with a voltage signal which is 5 V in the measurement state of the circuit arrangement being applied to the base connection of said transistor.

5. The circuit arrangement of claim 1 , wherein the measurement current impressed by the constant current source into the at least one coil winding of the at least one solenoid valve is configured so that solenoid valve type is detectable, but the flow of said measurement current does not yet result in functional activation of a respectively measured solenoid valve, and the measurement current is approximately 9 mA.

6. The circuit arrangement of claim 1 , wherein the current mirror circuit includes an operational amplifier, a transistor and a second resistance, which forms the detection section, and the current mirror circuit transmits the first voltage to a first resistance, which is connected to the transistor towards the vehicle electrical distribution system supply voltage.

7. The circuit arrangement of claim 1 , wherein at least one first high-side switch for activating the coil of the at least one solenoid valve is in series with the at least one solenoid valve, a second switch, which is common for the at least one solenoid valve, is in parallel with the constant current source to ground potential, wherein said second switch is closed in the normal operating state, and a third switch for switchably impressing the constant current is at the constant current source, and wherein, in a measurement operation state, the third switch is closed, the second switch is open, and the at least one first switch is closed.

8. The circuit arrangement of claim 1 , wherein a sensitivity and/or a detection range of the circuit arrangement is adjustable, wherein the resistance of the solenoid coils is calculated via the transformation ratio of the first voltage to the second voltage and the impressed measurement current.

9. The circuit arrangement of claim 1 , wherein the circuit arrangement forms part of an anti-lock braking system and/or part of a traction control system for a utility vehicle.

10. The circuit arrangement of claim 1 , wherein a battery is provided as a vehicle electrical distribution system supply voltage, a first resistance and at least one first switch are connected at in each case one first connection to a high potential of the vehicle electrical distribution system supply voltage, a transistor is connected at an emitter connection to the first resistance, an operational amplifier is connected at an output thereof to a base connection of the transistor, an inverting input of the operational amplifier is connected to the first resistance and to the emitter connection of the transistor, a noninverting input of the operational amplifier is connected to a first connection of a second switch, a first connection of a third switch, and a second connection of the at least one solenoid valve, a first connection of the at least one solenoid valve is connected to a second connection of the at least one first switch, a collector connection of the transistor is connected to a first connection of a second resistance, a second connection of the third switch is connected to a first connection of the constant current source, and in each case a second connection of the second resistance, a second connection of the constant current source, and a second connection of the second switch are connected to a low potential of the vehicle electrical distribution system supply voltage, wherein the second voltage as measurement voltage is passed out to the microcontroller between the first connection of the second resistance and the collector connection of the transistor.

11. The circuit arrangement of claim 1 , wherein the detected type of solenoid valve is a vehicle electrical distribution system supply voltage for which the solenoid valve is designed, wherein the vehicle electrical distribution system supply voltage includes rated voltages of more than 24 V, and in that the solenoid valve is a pressure control solenoid valve for use in braking systems and/or traction control systems of a utility vehicle.

Assignees

• Knorr Bremse Systeme Fuer Nutzfahrzeuge Gmbh

Inventors

• Scholl Frank
• Wieder Gerhard
• Winz Dieter

Classifications

• B60T1/00

  Arrangements of braking elements, i.e. of those parts where braking effect occurs {specially for vehicles} · CPC title

• B60T2270/406

  Test-mode; Self-diagnosis · CPC title

• B60T7/00

  Brake-action initiating means · CPC title

• G01R31/007 Primary

  using microprocessors or computers · CPC title

• F16K1/00

  Lift valves {or globe valves}, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces ({in combination with sliding valves F16K3/246, F16K3/267} ; diaphragm valves F16K7/00) · CPC title