THERMALLY-RESPONSIVE CONTROLLED CHARGING ARRANGEMENT FOR STORAGE BATTERIES

• US 3,599,071 A
• Filed: 10/13/1969
• Issued: 08/10/1971
• Est. Priority Date: 10/15/1968
• Status: Expired due to Term

• Current Assignee: Pierre Godard, Robert Henri
• Original Assignee: Pierre Godard, Robert Henri
• Inventors: Henri, Robert, Godard, Pierre
• Application Number:
  US04/865,546
• Time in Patent Office: 666 Days
• US Class Current: 320/150
• CPC Class Codes: H02J 7/007194 of the battery
• CPC Class Codes: H02J 9/00 Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
• CPC Class Codes: H02J 9/061 for DC powered loads
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y04S 20/20 End-user application control systems
• CPC Class Codes: Y10S 320/29 Transformer having plural secondaries

Abstract

Thermally-responsive charging arrangement for a storage battery supplied from an AC source to provide DC charging voltage to the storage battery terminals, the arrangement being capable of charging at a high rate or at lower or zero rates as required, including a thermal probe responsive to battery temperature and a thermal probe responsive to ambient temperature, these probes being interconnected to supply a signal output which is a function of the difference between battery and ambient temperatures. The signal output actuates a control for the charging arrangement to switch its operation from high to lower or zero charging rates and vice versa respectively when the temperature difference detected by the thermal probes has a determined maximum value and a determined minimum value. The thermal probes may be resistances or transistors conductivity of which are functions of their temperatures. Timing means are also provided for limiting the period during which the battery is charged at a high rate.

Claims

1. A thermally responsive arrangement for charging a storage battery from a source of supply comprising a charging circuit supplied by said source for delivering DC charging current to the battery, control means connected to said charging circuit for switching the charging rate of said current between a higher value and a lower value in response to a signal, a first thermal probe means responsive to battery temperature, a second thermal probe means responsive to ambient temperature, an electric circuit interconnecting said thermal probe means to provide a signal output which is a function of the difference between battery temperature and ambient temperature, signal output actuated means connected to said control means and actuated by said signal output for changing over the charging current rate from the higher value to the lower value when the temperature difference becomes equal to or greater than a determined maximum value and from tHe lower value to the higher value when the temperature difference becomes less than or equal to a determined minimum value, and electronic timing means connected to said signal actuated means for limiting the time period during which said signal output actuated means can act upon said control means to charge the battery at the higher value charging rate following interruption and restoration of power from said source.

2. A thermally responsive charging arrangement for a storage battery according to claim 1, wherein said thermal probe means each comprise electrically conductive components whose resistance varies as a function of the temperature of the component.

3. A thermally responsive arrangement for charging a storage battery from a source of supply comprising a charging circuit supplied by said source for delivering DC charging current to the battery, control means connected to said charging circuit for switching the charging rate of said current between a higher value and a lower value in response to a signal, a first thermal probe means responsive to battery temperature, a second thermal probe means responsive to ambient temperature, an electric circuit interconnecting said thermal probe means to provide a signal output which is a function of the difference between battery temperature and ambient temperature, signal output actuated means connected to said control means and actuated by said signal output for changing over the charging current rate from the higher value to the lower value when the temperature difference becomes greater than or equal to a determined maximum value and from the lower value to the higher value when said temperature difference becomes less than or equal to a determined minimum value, said thermal probe means each comprising a transistor having an emitter, base, and collector whose resistance at a junction varies as a function of temperature.

4. A thermally responsive arrangement for charging a storage battery from a source of supply comprising a charging circuit supplied by said source for delivering DC charging current to the battery, control means connected to said charging circuit for switching the charging rate of said current between a higher value and a lower value in response to a signal, a first thermal probe means responsive to battery temperature, a second thermal probe means responsive to ambient temperature, each of said thermal probe means being thermal probe transistors including respectively emitters, collectors and bases, each of whose resistances at a junction varies as a function of temperature, an electric circuit interconnecting said thermal probe means to provide a signal output which is a function of the difference between battery temperature and ambient temperature, signal output actuated means connected to said control means and actuated by said signal output for changing over the charging current rate from the higher value to the lower value when said temperature difference reaches or exceeds a determined maximum value and from the lower value to the higher value when said temperature difference becomes less than or equal to a determined minimum value, said thermal probe transistors being interconnected in said electric circuit as a differential circuit which produces and amplifies said signal output.

5. The arrangement of claim 4, in which the thermal probe transistors have their respective emitters connected together and to an output terminal of said charging circuit and have their respective collectors connected to another output terminal of said charging circuit, by way of resistor-type dividing bridges connected to polarize said transistors to control the said signal output to actuate said control means to control said charging rate.

6. A thermally responsive charging arrangement for a storage battery according to claim 4, including a third transistor connected between said thermal probe transistors and said control means such that the changeover of said third transistor between blocked and conductive states is determined by the value of said signal output from said thermal probe transistors, said changeover actuating said control means to cause said charging circuit to switch its charging rate between the higher and lower values.

7. A thermally responsive charging arrangement for a storage battery according to claim 1, in which said electronic timing means comprises a first and a second storage cell, means interconnecting said storage cells for enabling one cell to be charged by said arrangement simultaneously with the discharge of the other cell, a fourth transistor connected to be polarized to conductive state by and during the discharging of either of said cells at or above a predetermined rate of discharge, a fifth transistor connected to be maintained in a blocked state when said fourth transistor is conductive, the reduction of discharge rate of the discharging one of said cells below said predetermined rate causing said fourth transistor to be blocked and said fifth transistor to become conductive, and connections between said fifth transistor and said control means which maintain the charging rate of said charging circuit at its low value while said fifth transistor is conductive, whereby the reduction in the rate of discharge of the cell which is discharging below the predetermined rate of discharge precludes the charging circuit from charging at the higher rate.

8. A thermally responsive charging arrangement for a storage battery according to claim 7 in which said timing means further comprise a relay responsive to breakdown and restoration of said source of supply, said relay being electrically connected with respect to said storage cells so that upon reestablishment of the supply after the breakdown said relay effects recharging of the storage cell which has become discharged and effects polarization of said fourth transistor to a conductive state by the discharge of the other of said storage cells which has already been charged.

9. A thermally responsive charging arrangement for a storage battery according to claim 3 wherein said thermal probe transistors comprise base-emitter circuits connected electrically via their bases, one of said transistors being connected as a diode, said arrangement also comprising resistors, said transistors being connected in series with at least one of the resistors so that the source of current flowing in said one resistor is divided between the thermal probe transistors in accordance with their temperature change of resistance, switching means for the charging arrangement capable of alternating said rate of charge between its higher and lower values, and a third transistor controlled by one of the two thermal probe transistors so as to actuate said switching means.

10. A thermally responsive charging arrangement for a storage battery according to claim 3 further comprising timing means for limiting the time period during which said signal output actuated means can act upon said control means for charging the battery at the higher value charging rate, following interruption and restoration of power from said source.

11. A thermally responsive charging arrangement for a storage battery according to claim 9, wherein said switching means comprises a relay, said relay being of the electromagnetic type and having bridging contact means moveable to insert into and remove from the charging circuit a limiting resistor for limiting the charging rate of the battery, said control relay being connected to an additional relay in the collector circuit of the transistor connected as a diode, so as to increase the resistance in said collector circuit when said control relay is positioned to remove said resistor from the charging circuit.

12. A thermally responsive charging arrangement for a storage battery according to claim 11, in which said source is an AC source, and in which charging of the battery is effected by DC voltage, after rectification of AC supply and including a transformer with two windings, one of said windings being connected across the charging circuit comprising the said limiting resistor, and the other winding supplying, after rectification, the transistors and their respective circuits.

13. A thermally responsive charging arrangement for a storage battery according to claim 9 wherein the control means comprise a control transistor, controlled by the said third transistor and directly effecting the charging circuit to regulate the charging rate.

14. A thermally responsive charging arrangement for a storage battery according to claim 13 including another transistor electrically interposed between said third transistor and said control transistor, and a time delay circuit controlling said another transistor, whereby said control transistor, and said charging rate of said charging circuit can be regulated by the time delay circuit.

15. A thermally responsive charging arrangement according to claim 25 wherein said first and second thermal probe means comprise transistors, the resistances across elements thereof being dependent on temperature.

16. A thermally responsive charging arrangement according to claim 3 and further comprising a heat absorptive mass thermally associated with said probe responsive to ambient temperature, the thermal inertia of said mass being substantially equal to that of said battery.

17. A thermally responsive arrangement for charging a storage battery from a source of supply comprising a charging circuit supplied by said source for delivering DC charging current to the battery, control means connected to said charging circuit for switching the charging rate of said current between a higher value and a lower value in response to a signal, a first thermal probe means responsive to battery temperature, a second thermal probe means responsive to ambient temperature, an electric circuit interconnecting said thermal probe means to provide a signal output which is a function of the difference between battery temperature and ambient temperature, signal output actuated means connected to said control means and actuated by said signal output for changing over the charging current rate from the higher value to the lower value when the temperature difference reaches or exceeds a determined maximum value and from the lower value to the higher value when the temperature difference reaches or falls below a determined minimum value said arrangement additionally having means for overriding said electric circuit and control means to permit establishment of a high rate of charge of the battery immediately following a discharge of said battery, notwithstanding that the discharge has raised the temperature of the battery such that the difference between the ambient and the battery temperature exceeds said predetermined maximum value.

18. The arrangement of claim 17, in which said means for overriding includes a mass having thermal inertia substantially equal to that of the battery in thermal contact with the probe means responsive to ambient temperature, a shunt impedance connected to carry battery discharge current, the shunt being positioned to heat the mass when the battery discharges, the degree of said heating being thereby a function of the amount of discharge of the battery.

19. The arrangement of claim 1 having a heat absorptive mass whose thermal inertia is approximately equal to that of the battery in thermal contact with said probe means responsive to the ambient temperature.

20. The arrangement of claim 3 having a heat absorptive mass whose thermal inertia is approximately equal to that of the battery in thermal contact with said probe means responsive to the ambient temperature.

21. The arrangement of claim 4 having a heat absorptive mass whose thermal inertia is approximately equal to that of the battery in thermal contact with said probe means responsive to the ambient temperature.

22. The arrangement of claim 25 having a heat absorptive mass whose thermal inertia is approximately equal to that of the battery in thermal contact with said probe means responsive to the ambient temperature.

23. A thermally responsive charging arrangement for a storage battery according to claim 10, comprising further an additional transistor connected to and serving to lock the thermal transistor probe responsive to ambient temperature in a given state, and a relay having a bridging contact, said additional transistor being actuated to lock said thermal transistor probe responsive to ambient temperature in a given state upon the closing of the bridging contact, said arrangement in rendered incapable of charging the battery at the higher rate.

24. The arrangement of claim 23, further including a time delay transistor stage responsive to breakdown and restoration of power from said source connected to said additional transistor whereby said additional transistor is actuated at a predetermined elapsed time after breakdown and restoration of power from said source.

25. A thermally responsive charging arrangement for charging a storage battery, capable of serving also as the emergency supply in case of breakdown of a power source, comprising a charger supplied by a source of AC current, and whose output supplies a DC output connected to the terminals of the said battery, said charger being able to charge the battery alternatively either at a high rate, or at a lower rate, a first thermal probe means maintained at ambient temperature, a second thermal probe means arranged in such a manner as to be maintained constantly at the internal temperature of the battery, the said first and second thermal probe means being disposed in relation to each other so as to supply a signal which is a function of the difference between the temperature of the battery and ambient temperature, signal actuated means which under the action of the said signal cause charging to change from the high rate to charging at lower rate when the said difference reaches a first given maximum value, and which cause charging to change from the lower rate to the high rate when the said difference reaches a second given minimum value, and timing means which limits the period during which the said signal actuated means can act to effect charging of the battery at the high rate.

26. A thermally responsive charging arrangement for a storage battery according to claim 25, wherein the said thermal probe means each comprise an electrically conductive component whose resistance has a value which is a function of temperature.

27. A thermally responsive charging arrangement for a storage battery according to claim 26 including a transistorized differential detection circuit which produces and amplifies said signal, said circuit comprising a first and a second transistor whose emitters are connected together and are connected to an output terminal of the charging arrangement and whose collectors are connected to another output terminal of the said arrangement, a divider bridge of resistors for polarizing said transistors, one of which is one of the thermal probe means.

28. A device in accordance with claim 25, wherein said signal actuated means comprise a third control transistor, the changeover of which, from the blocked state to the conductive state, is determined by the value of the said signal and controls the changeover from the lower rate of charging to the high rate of charging.