BATTERY CHARGING SYSTEM WITH REVERSE BATTERY PROTECTION

• US 3,659,182 A
• Filed: 09/03/1970
• Issued: 04/25/1972
• Est. Priority Date: 09/03/1970
• Status: Expired due to Term

• Current Assignee: PEI 1991 Acquisition Incorporated
• Original Assignee: Marion L. Snedeker
• Inventors: Snedeker, Marion L.
• Primary Examiner(s): Shoop, Jr., William M.
• Application Number:
  US05/069,253
• Time in Patent Office: 600 Days
• Field of Search: 307/127,314 320/25,26
• US Class Current: 320/165
• CPC Class Codes: H02J 7/0034 using reverse polarity correcting or protecting circuits mechanical means of polarity protection H02J7/0045
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/14 for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
• CPC Class Codes: Y10S 320/15 Polarity control

Abstract

A circuit prevents a generating machine from being operatively connected to a battery whenever the battery has been connected with a reverse polarity. The machine is coupled through the anode-cathode path of a silicon-controlled rectifier to the battery and the rectifier is switched on in response to current pulses in the field winding of the machine. A primary winding of a pulse transformer and the secondary winding of the pulse transformer are employed to supply gating pulses to the controlled rectifier. The transformer has a saturating winding which is energized when the battery is connected in a reverse direction so that no gating pulses are coupled through the transformer to the gate of the controlled rectifier to turn on the controlled rectifier.

Claims

1. In a generating system comprising a generating machine including a field circuit comprising a field winding and electrical connections for connecting a battery to be charged by said generating machine to said machine, said connections including switching means having first and second conditions for respectively electrically connecting and disconnecting said generating machine to and from said battery, said switching means requiring a predetermined electrical signal for actuation from its first condition to its second condition, second means for providing said electrical signal when said generating machine is generating an output comprising a transformer having a primary winding connected to said generating machine to be energized with a current which changes in a pulsing manner when said generating machine is operating and a secondary winding connected to said switching means to provide said predetermined signal in response to a predetermined pulsing change in said current, and third means responsive to reverse battery polarity for saturating said transformer to prevent current in said primary winding from inducing currents in said secondary winding to provide said predetermined signal.

2. In a generating system as defined in claim 1 wherein said generating machine is a machine which generates a direct current.

3. In a generating system as defined in claim 16 wherein said primary winding is connected into the field circuit of said generating machine.

4. In a generating system as defined in claim 3 wherein said switching means is a controlled rectifier and said secondary winding is connected to provide gate signals to said rectifier.

5. In a generating system as defined in claim 3 wherein said system includes a voltage regulator for regulating the output of said generating machine by controlling the current in said field winding in response to said output, said regulating means switching off and on as the output of said generating machine rises and falls to predetermined levels to provide said current which pulses in a predetermined manner.

6. In a generating system as defined in claim 4 wherein said system includes a voltage regulator for regulating the output of said generating machine by controlling the current in said field winding in response to said output, said regulating means switching off and on as the output of said generating machine rises and falls to predetermined levels to provide said current which pulses in a predetermined manner.

7. In a generating system as defined in claim 1 wherein said third means comprises a saturating winding for said transformer and circuit means connecting said saturating winding across the battery terminals of said battery, said circuit means including uni-directional conducting means for blocking current flow in said saturating winding when said battery is connected to the battery terminals with proper polarity and whereby said circuit means is conductive when said battery is inserted with reverse polarity to saturate said transformer.

8. In a generating system as defined in claim 7 wherein said switching means is a controlled rectifier and said secondary winding is connected to provide gate signals to said rectifier.

9. In a generating system as defined in claim 7 wherein said machine is a generating machine for generating a direct current and said primary winding is connected into the field circuit of said generating machine.

10. In a generating system as defined in claim 9 wherein said switching means is a controlled rectifier and said secondary winding is connected to provide gate signals to said rectifier.

11. In a generating system as defined in claim 9 wherein Said generating system includes voltage regulating machine responsive to the output of said generating means for controlling the field current in said field winding, said voltage regulating means switching said field current off and on as the output of said generating machine rises and falls to predetermined levels to provide said current which pulses in a predetermined manner.

12. In a generating system, generating means to be connected to supply direct current to charge a battery, said generating means having a field circuit comprising a field winding, load conductors connecting the output of said generating means to said battery, switching means in said load conductors for connecting and disconnecting the output of said generating means to and from said battery, means for sensing current in said field circuit, and means responsive to the last said means for supplying a signal to said switching means to activate the latter to connect the generating means to said battery when the generating means has started.

13. In a generating system as defined in claim 12 wherein said means for sensing current in said field circuit comprises a circuit element connected in series with said field winding.

14. In a generating system as defined in claim 12 in which said generating system includes means responsive to the polarity of said battery for inhibiting the activation of said switching means in response to said means for sensing current in said field.

15. In a generating system as defined in claim 14 wherein said switching means comprises a controlled rectifier having its anode connected to the positive side of said generating means.