← Back to Patent Explorer
US4217536A Expired / Lapsed US ⏱️ 0.0 years remaining

Supply voltage monitoring device for automotive battery

Assignee: Sawafuji Electric Co Ltd
•
Filing: 1978-04-24
•
Granted: 1980-08-12
•
Expires: 1998-04-24
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A supply voltage monitoring device for an automotive battery comprising an average voltage generation circuit for generating the average voltage of the supply voltage of a battery as a power source for various equipment on board an automobile, a Zener diode conducting when the output voltage of the average voltage generation circuit exceeds the prescribed value, a first transistor connected between the Zener diode and the average voltage generation circuit, a second transistor controlled by the conducting Zener diode, a capacitor controlled for charging and discharging by the output of the second transistor, third transistors controlled by the output voltage of the capacitor, and a light emitting diode controlled for the light emitting state or the non-emitting state by the second transistor or the third transistors, and characterized in that the device is constructed to monitor the supply voltage of the battery by the light emitting state or the non-emitting state of the light emitting diode.

Inventors

  • 👤 Toshio Izumi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 22:22
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/165; G01R19/16533; G01R19/16538; G01R19/16542; F; F25; F25D; F25D29/00; F25D29/006; G01R31/00; G01R31/005; G01R31/006; H; H02; H02J; H02J7/00; H02J7/14; H02J7/80; Y; Y10; Y10S; Y10S320/00; Y10S320/18; Y10S320/21

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 148 words
A supply voltage monitoring device for automotive battery for monitoring the supply voltage of an automotive battery used as a power source for various on-board equipment, having an average voltage generation circuit for producing the average voltage of the battery supply voltage, a Zener diode which conducts only when the output voltage of the average voltage generation circuit exceeds the prescribed value, a first transistor connected between the Zener diode and the average voltage generation circuit, a second transistor controlled by the conducting Zener diode, a capacitor controlled by the output of the second transistor, third transistors controlled by the output voltage of the capacitor, and a light emitting diode whose light emitting state is controlled by at least the third transistors, and characterized in that the device is constructed so as to monitor the battery supply voltage by the light emitting state of the light emitting diode.
Claim 2
Dependent Claim 148 words
A supply voltage monitoring device for automotive battery for monitoring the supply voltage of an automotive battery used as a power source for various on-board equipment, having an average voltage generation circuit for producing the average voltage of the battery supply voltage, a Zener diode which conducts only when the output voltage of the average voltage generation circuit exceeds the prescribed value, a first transistor connected between the Zener diode and the average voltage generation circuit, a second transistor controlled by the conducting Zener diode, a capacitor controlled by the output of the second transistor, third transistors controlled by the output voltage of the capacitor, and a light emitting diode whose light emitting state is controlled by at least the third transistors, and characterized in that the device is constructed so as to monitor the battery supply voltage by the light emitting state of the light emitting diode.
Claim 3
Dependent Claim 29 words
A supply voltage monitoring device for automotive battery as set forth in claim 1 wherein the light emitting diode is connected to the output circuit of the third transistors.
Claim 4
Dependent Claim 49 words
A supply voltage monitoring device for automotive battery as set forth in claim 1 wherein a changeover switch is provided to change over the connection of the light emitting diode from the output circuit of the second transistor to the output circuit of the third transistors, and vice versa.
Claim 5
Dependent Claim 46 words
A supply voltage monitoring device for automotive battery as set forth in claim 1 wherein a switching circuit controlled by the output of the third transistors is provided between the battery and the load powered by the battery for controlling the power supply to the load.
Claim 6
Dependent Claim 36 words
A supply voltage monitoring device for automotive battery as set forth in claim 4 wherein signal output terminals are provided on the output side of the third transistors for connecting the output of the third transistors.
Claim 7
Dependent Claim 37 words
A supply voltage device for automotive battery as set forth in claim 1 characterized in that the said device is adapted for installation on an outer part of an electric refrigerator powered by a vibration type motor.

References Cited (Backward Citations)

US3568175A Cited
US4019112A Cited
US3939421A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-08-12 1984-02-11 1984-08-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-08-12 1988-02-11 1988-08-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-08-12 1992-02-11 1992-08-12 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag