GLOW TIME CONTROL DEVICE

• US 20150101556A1
• Filed: 02/07/2013
• Published: 04/16/2015
• Est. Priority Date: 03/03/2012
• Status: Active Grant

• Current Assignee: Volkswagen AG
• Original Assignee: Volkswagen AG
• Inventors: Habermann, Viktoria, Schillinger, Wolf-Rdiger
• Granted Patent: US 9,790,912 B2
• Time in Patent Office: Days
• US Class Current: 123/145.A
• CPC Class Codes: F02M 31/125 Fuel
• CPC Class Codes: F02P 19/021 characterised by power delivery controls
• CPC Class Codes: F02P 19/023 Individual control of the glow plugs
• CPC Class Codes: F02P 19/027 Safety devices, e.g. for diagnosing the glow plugs or the related circuits
• CPC Class Codes: H02H 11/006 in case of too high or too low voltage
• CPC Class Codes: H03K 17/082 by feedback from the output to the control circuit
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

The present invention relates to a glow time control device (100) for controlling glow rods (206-209) in a vehicle (200). The glow time control device (100) comprises a control unit (IC1), at least two power transistors (T1, T4) and a protective circuit (T6, T7). The control unit (IC1) comprises a control output (GG1) for emitting a control signal, a supply voltage input (VCC) and a supply voltage output (VDD). The control unit (IC1) provides an output voltage at the supply voltage output (VDD) depending on a voltage at the supply voltage input (VCC). A corresponding glow rod control output (G1, G4) is assigned to each of the power transistors (T1, T4) and the control inputs of the power transistors (T1, T4) are coupled to the control output (GG1). The protective circuit (T6, T7) comprises a protective circuit output which is coupled to the control inputs of the power transistors (T1, T4), and an input which is coupled to the supply voltage output (VDD). The protective circuit adjusts a predefmed potential at the protective circuit output if the output voltage of the control unit (IC1) is below a predefmed value.

Claims

1. A glow control unit for actuating glow pencils in a motor vehicle, comprising:

a control unit having a control output for emitting a control signal, a supply-voltage input and a supply-voltage output, whereby the control unit is configured to provide an output voltage at the supply-voltage output as a function of the voltage at the supply-voltage input;

at least two power transistors, each of which is associated with a glow pencil control output and whose control inputs are coupled to the control output of the control unit; and

a protective circuit having a protective circuit output that is coupled to the control inputs of the at least two power transistors, and having an input that is coupled to the supply-voltage output of the control unit, whereby the protective circuit is configured to set a prescribed potential at the protective circuit output if the output voltage of the control unit is below a prescribed value.

2. The glow control unit according to claim 1, whereby the prescribed potential is a potential that blocks the at least two power transistors.

6. The glow control unit according to claim 3, whereby the glow control unit is configured according to claim 1.

8. The glow control unit according to claim 7, whereby the glow control unit is configured according to claim 1.

11. The glow control unit according to claim 9, whereby the glow control unit is configured according to claim 1.

14. The glow control unit according to claim 12, whereby the glow control unit is configured according to claim 1.

15. A vehicle, comprising:

at least one glow pencil, and

a glow control unit according to one of claim 1, 3, 7, 9 or 12, which is coupled to the at least one glow pencil.

3. A glow control unit for actuating glow pencils in a motor vehicle, comprising:

a control unit having a control output for emitting a control signal;

at least two power transistors each of which is associated with a corresponding glow pencil control output and whose control inputs are coupled to the control output of the control unit; and

at least two transistors that are each associated with one of at least two power transistors, whereby an interrupter of the transistor associated with a power transistor is located between the control input and an output of the associated power transistor, whereby a diode is located between the transistor and the control input of the power transistor.

4. The glow control unit according to claim 3, whereby the power transistor comprises a field-effect transistor having a gate terminal as the control input as well as a source terminal, whereby an emitter of the transistor is coupled to the source terminal, a collector terminal of the transistor is coupled to the gate terminal via the diode, and a base of the transistor is coupled to the source terminal via a capacitor, and coupled to a chassis terminal of the glow control unit via an additional diode.

5. The glow control unit according to claim 3, whereby the diode is a Schottky diode.

7. The glow control unit for actuating glow pencils in a vehicle, comprising:

a control unit having a control output for emitting a control signal;

at least two power transistors, each of which is associated with a corresponding glow pencil control output and whose control inputs are coupled to the control output of the control unit; and

at least two pairs of Zener diodes, each of which is associated with one the at least two power transistors, whereby the pair of Zener diodes associated with a power transistor is connected between the control input and an output of the power transistor, whereby the pair of Zener diodes comprises a series connection of two Zener diodes connected in the opposite direction.

9. A glow control unit, comprising:

a printed circuit board,

a chassis terminal that is coupled to a first conductor of the printed circuit board;

at least one electric terminal on the printed circuit board that is coupled to a second conductor of the printed circuit board and it is configured to electrically connect the second conductor to a device that is external to the glow control unit; and

an ESD spark gap that is formed adjacent to the electric terminal between the first conductor and the second conductor.

10. The glow control unit according to claim 9, whereby the ESD spark gap comprises an air gap that is located between the first conductor and the second conductor and that has the prescribed length.

12. A glow control unit for actuating glow pencils in a vehicle, comprising:

at least two power transistors, each of which is associated with a corresponding glow pencil control output; and

and at least two fuses, each of which is associated with one of the at least two power transistors.

13. The glow control unit according to claim 12, whereby the fuse (9-12) is a fusible cutout.