Voltage regulator for charging generator

• US 4,618,811 A
• Filed: 02/10/1984
• Issued: 10/21/1986
• Est. Priority Date: 02/10/1983
• Status: Expired due to Term

• Current Assignee: Hitachi Automotive Engineering Company Limited (Hitachi, Ltd.), Hitachi, Ltd.
• Original Assignee: Hitachi Automotive Engineering Company Limited (Hitachi, Ltd.), Hitachi, Ltd.
• Inventors: Kobayashi, Kunio, Mashino, Keiichi, Miki, Osamu, Masumoto, Shouju, Satou, Morio
• Primary Examiner(s): Hickey, R. J.
• Application Number:
  US06/578,794
• Time in Patent Office: 984 Days
• Field of Search: 322/28, 322/99, 320/64, 320/68, 320/61
• US Class Current: 322/28
• CPC Class Codes: H02H 7/067 on occurrence of a load dump control on sudden change of load H02P9/10
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/16 Regulation of the charging current or voltage by variation of field
• CPC Class Codes: Y10S 320/13 Fault detection

Abstract

A voltage regulator for a charging generator is disclosed which comprises an a.c. generator having armature windings and a field winding, and a battery which receives the rectified output of the a.c. generator and is charged by the same. The voltage regulator regulates the output voltage of the a.c. generator by controlling the current flowing through the field winding. To prevent the output voltage of the a.c. generator from becoming a high voltage when a connecting wire connecting the rectified output of the a.c. generator to the battery is broken, the regulator also includes an abnormality detection means which compares the rectified output of the a.c. generator with the battery voltage and detects the abnormality when both voltages are different by more than a predetermined value. This arrangement makes it possible to detect the abnormality at the point of time where the output voltage of the a.c. generator is not yet very high.

Claims

1. A voltage regulator for a charging generator comprising:

an a.c. generator having armature windings and a field winding;

rectification means for rectifying an a.c. output of said a.c. generator to a d.c. output;

a battery connected to an output terminal of said rectification means to receive power from said a.c. generator;

an initial exciting current supply circuit including a key switch and a charge lamp connecting said battery to said field winding;

a load connected parallel to said field winding;

a voltage regulator including means for comparing the battery voltage with a reference voltage and means for controlling a current flowing through said field winding in accordance with an output of said comparing means; and

abnormality detection means for comparing an output voltage of said rectification means with the battery voltage and producing an abnormality indication output when a difference between both voltages exceeds a predetermined value, wherein said current controlling means in said voltage regulator cuts off a current flowing through said field winding in accordance with the abnormality indication output of said abnormality detection means so that the power generation of said a.c. generator is stopped and a current from said battery flows through said initial exciting current supply circuit and said load to light said charge lamp in said initial exciting current supply circuit.

2. The voltage regulator for a charging generator as defined in claim 1 wherein said abnormality detection means includes a differential amplifier detecting the voltage difference between the output voltage of said rectification means and the battery voltage, and a comparator producing said abnormality indication output when the output of said differential amplifier exceeds a predetermined value.

3. The voltage regulator for a charging generator as defined in claim 1 wherein said abnormality detection means comprises a comparator including means for detecting a ratio of the output voltage of said rectification means to the battery voltage and means for producing said abnormality indication output when said ratio exceeds a predetermined value.

4. The voltage regulator for a charging generator comprising:

an a.c. generator having armature windings and a field winding;

rectification means for rectifying an a.c. output of said a.c. generator to a d.c. output;

a battery connected to an output terminal of said rectification means to receive power from said a.c. generator through said rectification means;

a voltage regulator including means for comparing the battery voltage with a reference voltage and means for controlling a current flowing through said field winding in accordance with an output of said comparing means;

abnormality detection means for comparing an output voltage of said rectification means with the battery voltage and producing an abnormality indication output when a difference between both voltages exceeds a predetermined value; and

current cut-off means for controlling said voltage regulator in accordance with the abnormality indication output of said abnormality detection means and for cutting off the current supplied to said field winding in accordance with said abnormality indication output which further includes a holding circuit for holding the output of said abnormality detection means until said holding circuit is reset.

5. A voltage regulator for a charging generator comprising:

an a.c. generator having armature windings and a field winding;

main rectification means for converting an a.c. output of said a.c. generator to a d.c. output;

a battery connected to an output terminal of said main rectification means to receive power from said a.c. generator;

said field winding being connected to an output terminal of said auxiliary rectification means;

an initial exciting current supply circuit including a key switch and a charge lamp connecting said battery to said field winding;

a load connected to the output terminal of said auxiliary rectification means;

comparison means for comparing the battery voltage with a reference voltage;

switching means for controlling a current flowing through said field winding in accordance with the output of said comparison means;

abnormality detection means comparing an output voltage of said auxiliary rectification means with the battery voltage and generating an abnormality indication output when a difference of both voltages exceeds a predetermined value, wherein said swithcing means cuts off a current flowing through said field winding in accordance with the abnormality indication output of said abnormality detection means so that the power generation of said a.c. generator is stopped and a current from said battery flows through said initial exciting current supply circuit and said load to light said charge lamp in said initial exciting current supply circuit.

6. The voltage regulator for a charging generator as defined in claim 5 wherein said abnormality detection means includes a differential amplifier detecting the difference between the output voltage of said auxiliary rectification means and the battery voltage and a comparator generating said abnormality indication output when the output voltage of said differential amplifier is greater than a set voltage.

7. The voltage regulator for a charging generator comprising:

an a.c. generator having armature windings and a field winding;

main rectification means and auxiliary rectification means, each including means for converting an a.c. output of said a.c. generator to a d.c. output;

a battery connected to an output terminal of said main rectification means to receive power from said a.c. generator through said rectifier;

said field winding being connected to said battery through a key switch and a charge lamp and to an output terminal of said auxiliary rectification means;

comparison means for comparing the battery voltage with a reference voltage;

switching means subjected to control by an output of said comparison means and including means for controlling a current flowing through said field winding in accordance with the output of said comparison means;

abnormality detection means comparing the output voltage of said auxiliary rectification means with the battery voltage and generating an abnormality indication output when a difference of both voltages exceeds a predetermined value;

current cut-off means for controlling said switching means in accordance with the abnormality indication output of said abnormality detection means and for cutting off the current supplied to said field winding in accordance with said abnormality indication output; and

a load connected to said charge lamp on the opposite side to said battery;

wherein a current flows through a circuit which includes said battery, said charge lamp and said load when an abnormality occurs, and said lamp is lit to raise an alarm of said abnormality which further includes a holding circuit for holding the output of said abnormality detection means until said holding circuit is reset.