Circuit for a latching relay

• US 6,323,562 B1
• Filed: 07/21/1999
• Issued: 11/27/2001
• Est. Priority Date: 01/28/1997
• Status: Expired due to Term

• Current Assignee: Seg Automotive Germany GMBH
• Original Assignee: Robert Bosch GmbH
• Inventors: Daurer, Uwe, Renner, Stefan, Schmidt, Karl-Otto, Kramer, Claus
• Primary Examiner(s): ENAD, ELVIN GENARGUE
• Application Number:
  US09/355,007
• Time in Patent Office: 860 Days
• Field of Search: 290/38.A, 290/38.B, 290/38.R, 290/40-A-, 123/179, 74/7.A
• US Class Current: 290/38.00A
• CPC Class Codes: F02N 11/0851 characterised by means for controlling the engagement or disengagement between engine and starter, e.g. meshing of pinion and engine gear
• CPC Class Codes: F02N 11/087 Details of the switching means in starting circuits, e.g. relays or electronic switches
• CPC Class Codes: F02N 15/067 the starter comprising an electro-magnetically actuated lever
• CPC Class Codes: F02N 2200/045 Starter temperature or parameters related to it
• CPC Class Codes: F02N 2200/047 Information about pinion position
• CPC Class Codes: F02N 2200/066 Relay temperature

Abstract

A circuit arrangement for an engagement relay of a starter mechanism of an internal combustion engine, for bringing two gearwheels in engagement, the circuit arrangement having a switching element which reduces a relay current after a first time period before meshing of the two gear wheels to a determined current value during a second time period, the switching element being formed as a controlling and regulating device which increases a relay current to a predetermined value to a third time period which starts when one gear wheel reaches the other gear wheel.

Claims

1. A circuit arrangement for an engagement relay of a starter mechanism of an internal combustion engine, for bringing two gearwheels in engagement, said circuit arrangement comprising a switching element which reduces a relay current after a first time period before meshing of the two gear wheels to a determined current value during a second time period, said switching element being formed as a controlling and regulating device which increases a relay current to a predetermined value to a third time period which starts when one gear wheel reaches the other gear wheel.

2. A circuit arrangement as defined in claim 1, wherein said controlling and regulating device include a current sensor which detects the relay current.

3. A circuit arrangement as defined in claim 2, wherein said controlling and regulating device is formed so that it regulates the relay current depending on a measurement signal of said current sensor.

4. A circuit arrangement as defined in claim 3, wherein said controlling and regulating device regulates the relay current by a two-step regulator.

5. A circuit arrangement as defined in claim 1;

and further comprising means for connecting the engagement relay in series with a winding of a starter motor selected from the group consisting of an armature winding and an exditation winding, which is activated at low output at least in a time period selected from the group consisting of said second period and said third period by the relay current.

6. A circuit arrangement as defined in claim 1, wherein said controlling and regulating device is formed so that it activates a starter motor at least in a time period selected from the group consisting of said second time period and said third time period.

7. A circuit arrangement as defined in claim 1;

and further comprising means for pulse-width modulation of a control signal which is sent by said controlling and regulating device to the engagement relay.

8. A circuit arrangement as defined in claim 7;

and further comprising means for carrying out a decrease in the relay current by changing a duty factor of the control signal.

9. A circuit arrangement as defined in claim 1;

and further comprising a meshing arrangement which rotates one of the two gear wheels relative to the other at low speed at least in a time period selected from the group consisting of the second time period and the third time period.

10. A circuit arrangement as defined in claim 1, wherein said controlling and regulating device includes a timing element which prevents a restarting of the starter mechanism before an expiration of a given period of time following a most recent start.

11. A circuit arrangement as defined in claim 1, wherein said controlling and regulating device is formed so that it regulates the relay current depending on determined state variables.