Electronic Battery Safety Switch

• US 20080151454A1
• Filed: 05/25/2005
• Published: 06/26/2008
• Est. Priority Date: 05/28/2004
• Status: Abandoned Application

• Current Assignee: Catem Develec GmbH
• Original Assignee: Catem Develec GmbH
• Inventors: Uhl, Gunter
• Application Number:
  US11/569,137
• Publication Number:
  US 20080151454A1
• Time in Patent Office: Days
• US Class Current: 361/87
• CPC Class Codes: B60R 16/03 for supply of electrical power to vehicle subsystems or for circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: B60R 21/01 Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents electrical circuits for transmission of signals between steering wheel and the vehicle itself B60R16/027; for electrically actuating belt retractor locking means B60R22/343
• CPC Class Codes: B60R 21/017 including arrangements for providing electric power to safety arrangements or their actuating means, e.g. to pyrotechnic fuses or electro-mechanic valves

Abstract

The invention relates to an electronic battery safety switch which facilitates a reliable and reversible disconnection of the motor vehicle on-board network from the battery. For this purpose an electronic solid-state switch is used which facilitates an unlimited number of switching cycles. The solid-state switch electrically disconnects the motor vehicle on-board network and the battery with the application of a crash signal or an overcurrent signal or when the ignition is switched off. With a parked vehicle an impermissibly high idle current and a discharge of the battery can be reliably prevented in an effective and simple manner. If the current flows from the on-board network in the direction of the battery, then the solid-state switch is switched actively conducting. Thus, damage to the switch in the inverse mode can be prevented.

Claims

1. Battery safety switch for the electrical disconnection of the battery of a motor vehicle and a motor vehicle on-board network, said battery safety switch comprising a solid-state switch for the connection and disconnection of the battery and the motor vehicle on-board network in dependence of an overcurrent and/or a crash signal,

wherein

the solid-state switch is designed for bi-directional operation of the current, and

the solid-state switch s switched conducting when the voltage of the on-board network is greater than the battery voltage.

2. Battery safety switch according to claim 1, wherein the solid-state switch a MOSFET.

3. Battery safety switch according to claim 1, wherein the solid-state switch disconnects the motor vehicle on-board network from the battery also in the position Ignition OFF.

4. Battery safety switch according to claim 3, wherein the solid-state switch disconnects electrical loads with a high idle current consumption, in particular electrical supplementary heaters and/or glow systems, from the battery in the position Ignition OFF.

5. Battery safety switch according to claim 1, wherein the solid-state switch equipped with a current measurement function for monitoring the current flowing out of the battery into the motor vehicle on-board network.

6. Battery safety switch according to claim 5, further comprising a control unit for the evaluation of the current measured by the solid-state switch and for the control of the solid-state switch for the disconnection of the electrical connection between the battery and the motor vehicle on-board network.

7. Battery safety switch according to claim 6, wherein the control unit compares the current measured by the solid-state switch with a specified limit.

8. Battery safety switch according to claim 7, wherein the limit can be adjusted adaptively.

9. Battery safety switch according to claim 7, wherein the control unit signals an overcurrent to the solid-state switch when the limit is exceeded.

10. Battery safety switch according to claim 1 wherein the crash signal is an air bag trigger signal.

11. Battery safety switch according to claim 1, which is designed for attachment to a battery terminal.

12. Battery safety switch according to claim 1, further comprising a battery monitoring systemize.

13. Battery safety switch according to claim 12, wherein the battery monitoring system monitors the voltage of the battery, the temperature of the battery and the current flowing into or out of the battery.

14. Battery safety switch according to claim 12, wherein the control unit determines the battery condition from the values measured by the battery monitoring system.

15. Battery safety switch according to claim 1, further comprising a monitoring device for monitoring the current flow out of the battery in the position Ignition OFF.

16. Battery safety switch according to claim 15, wherein the control unit averages the current values acquired by the monitoring device and on exceeding a specified limit also disconnects the loads connected in the position Ignition OFF from the battery.