← Back to Patent Explorer
US3921049A Expired / Lapsed US ⏱️ 0.0 years remaining

Charging circuit for battery-operated devices powered by solar cells

Assignee: Edgewell Personal Care Brands LLC
•
Filing: 1973-09-25
•
Granted: 1975-11-18
•
Expires: 1993-09-25
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A charging circuit for battery-operated devices powered by photovoltaic cells comprising a first diode means connected in parallel to a series-connected resistor and at least one photovoltaic cell, and in parallel to a series-connected second diode means and at least one secondary battery. The terminals of the components of the circuit are connected such that the current from the photovoltaic cells is limited by the first diode means so as to prevent overcharge of the secondary battery while the second diode means is connected so as to prevent reverse current through the photovoltaic cells when the voltage of the secondary battery is higher than that of said photovoltaic cells.

Inventors

  • 👤 Geoffrey W Mellors
  • 👤 Robert A Powers
  • 👤 Glenn W Sheffield

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 19:09
CPC Classifications
H; H02; H02J; H02J7/00; H02J7/34; H02J7/35; G; G04; G04C; G04C10/00; G04C10/02; H01; H01M; H01M10/00; H01M10/42; H01M10/44; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/56; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S136/00; Y10S136/291; Y10S320/00; Y10S320/22

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 205 words
A charging circuit for battery-operated devices powered by a photovoltaic battery comprising a photovoltaic battery having positive and negative terminals; resistive means connected in series to said photovoltaic battery; first diode means connected in parallel across said series-connected photovoltaic battery and resistive means so as to provide a first conductive circuit loop for said photovoltaic battery; second diode means connected in series to a rechargeable battery having positive and negative terminals; said rechargeable battery and second diode means connected in parallel across both the first diode means and the series-connected photovoltaic battery and resistive means; said photovoltaic battery and resistive means connected in terminal relationship with the rechargeable battery and second diode means so as to provide a second conductive circuit loop in which the photovoltaic battery will charge said rechargeable battery while said second diode means will prevent reverse current flow through said photovoltaic battery when the voltage of said rechargeable battery exceeds the voltage of said photovoltaic battery; said first diode means providing in said first conductive circuit loop a path so as to prevent excessively high current flow from said photovoltaic battery through said rechargeable battery; and output terminals connected across said rechargeable battery and adapted for coupling to a battery-powered device.
Claim 2
Dependent Claim 205 words
A charging circuit for battery-operated devices powered by a photovoltaic battery comprising a photovoltaic battery having positive and negative terminals; resistive means connected in series to said photovoltaic battery; first diode means connected in parallel across said series-connected photovoltaic battery and resistive means so as to provide a first conductive circuit loop for said photovoltaic battery; second diode means connected in series to a rechargeable battery having positive and negative terminals; said rechargeable battery and second diode means connected in parallel across both the first diode means and the series-connected photovoltaic battery and resistive means; said photovoltaic battery and resistive means connected in terminal relationship with the rechargeable battery and second diode means so as to provide a second conductive circuit loop in which the photovoltaic battery will charge said rechargeable battery while said second diode means will prevent reverse current flow through said photovoltaic battery when the voltage of said rechargeable battery exceeds the voltage of said photovoltaic battery; said first diode means providing in said first conductive circuit loop a path so as to prevent excessively high current flow from said photovoltaic battery through said rechargeable battery; and output terminals connected across said rechargeable battery and adapted for coupling to a battery-powered device.
Claim 3
Dependent Claim 14 words
The charging circuit of claim 1 wherein said photovoltaic battery is a solar battery.
Claim 4
Dependent Claim 17 words
The charging circuit of claim 1 wherein said rechargeable battery utilizes a solid ionically conducting electrolyte system.
Claim 5
Dependent Claim 13 words
The charging circuit of claim 1 wherein said first diode means are silicon.
Claim 6
Dependent Claim 13 words
The charging circuit of claim 1 wherein said second diode means are germanium.
Claim 7
Dependent Claim 31 words
The charging circuit of claim 1 for use in a battery-operated wristwatch wherein said photovoltaic battery is a solar battery and wherein said rechargeable battery utilizes solid ionically conducting electrolyte system.
Claim 8
Dependent Claim 25 words
The charging circuit of claim 6 wherein said first diode means are silicon diode means and wherein said second diode means are germanium diode means.
Claim 9
Dependent Claim 26 words
The charging circuit of claim 6 wherein said first diode means are three series-connected silicon diodes and wherein said second diode means is a germanium diode.
Claim 10
Dependent Claim 15 words
The charging circuit of claim 8 wherein said solar battery is a silicon solar battery.

References Cited (Backward Citations)

US3148322A Cited
US3419779A Cited
US3426263A Cited
US3427797A Cited
US3484659A Cited
US3731474A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-11-17 1979-05-19 1979-11-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-11-17 1983-05-19 1983-11-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-11-17 1987-05-19 1987-11-18 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag