Motor vehicle battery discharge load current control

• US 5,204,992 A
• Filed: 11/30/1990
• Issued: 04/20/1993
• Est. Priority Date: 11/30/1990
• Status: Expired due to Fees

• Current Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Carpenter, James A.
• Primary Examiner(s): Pellinen, A. D.
• Assistant Examiner(s): Osborn, David
• Application Number:
  US07/620,467
• Time in Patent Office: 872 Days
• Field of Search: 307/10.1, 307/10.6, 307/10.7, 307/10.8, 307/38, 307/39, 307/113, 307/115, 307/141.4, 307/592, 307/595, 307/596, 307/598, 307/603, 377/16, 377/107, 377/110, 320/38, 320/13, 340/636
• US Class Current: 307/10.7
• 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: H02J 1/14 Balancing the load in a network
• CPC Class Codes: H02J 2310/46 for ICE-powered road vehicles
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence

Abstract

A battery discharge load current control system for a motor vehicle electrical system. The system has a short term timer and a long term timer. The timers are comprised of pulse counters that count constant frequency clock pulses. The short term timer will disconnect certain inadvertent loads from the battery after the elapse of a time period. Inadvertent loads as those that are controlled by a control switch that has not been turned-off by the driver of a vehicle. The long term timer disconnects parasitic loads from the battery after the elapse of a time period. Parasitic loads are those that are normally permanently connected to the battery. The time periods can be varied as a function of the number of miles that the vehicle has been driven and are increased after the vehicle has been driven a predetermined number of miles. The short term timer can be reset to start a new timing cycle if the control switch is closed after the short term timer has disconnected the inadvertent load from the battery.

Claims

1. A battery discharge load current control system for a motor vehicle electrical system comprising, a battery, an electrical load, a load control switching means, means connecting one side of said switching means to one side of said battery, means including conductor means connecting an opposite side of said switching means to one side of said electrical load, a manually operable control switch connected between an opposite side of said electrical load and an opposite side of said battery, a pulse counter connected to a source of constant frequency clock pulses, said pulse counter coupled to said load control switching means, said pulse counter when reset to a zero count value causing said load control means to be activated to a closed condition to thereby connect said battery and said electrical load, said pulse counter operative to activate said load control means to an open condition to thereby disconnect said battery and electrical load after said pulse counter has counted a predetermined number of clock pulses corresponding to a predetermined time period and reset means coupled to said conductor means for resetting said pulse counter to said zero count value when said manually operable switch is closed at a time when said load control switching means is open.

2. The system according to claim 1 where a resistor is connected between one side of the battery and said conductor means whereby said conductor means develops a high to low voltage transition when said manually operable switch is closed at a time when said load control switching means is open, said reset means responding to said transition.

3. A battery discharge load current control system for a motor vehicle electrical system comprising, a battery, a first electrical load connected to said battery through a first switching means, said first electrical load drawing a relatively small battery discharge current of a first magnitude when connected to the battery, a second electrical load connected to said battery through a second switching means, said second electrical load when connected to said battery drawing a substantially higher battery discharge current when said first magnitude, first and second timer means, means connecting said first timer means to said first switching means including means for causing said first switching means to be activated to an open condition to disconnect the first load from the battery after the elapse of a first predetermined time period, means connecting said second timer means to said second switching means including means for causing said second switching means to be activated to open condition to disconnect the second load from the battery after the elapse of a second predetermined time period, said first time period being substantially longer than said second time period, means for determining the number of miles travelled by the motor vehicle, and means operative when said vehicle has travelled a predetermined number of miles for increasing said first and second time periods.

4. A battery discharge load current control system for a motor vehicle electrical system comprising, a battery, an electrical load connected to said battery through a switching means, timer means, means connecting said timer means to said switching means including means for causing said switching means to be activated to an open condition to disconnect said electrical load from the battery after the elapse of a time period, means for determining the number of miles travelled by the motor vehicle, and means operative when said vehicle has travelled a predetermined number of miles for increasing said timer period.

5. The electrical system according to claim 4 where said electrical load draws a relatively small discharge current when connected to said battery.