Battery monitoring and charging circuit for sump pumps

• US 5,015,152 A
• Filed: 11/20/1989
• Issued: 05/14/1991
• Est. Priority Date: 11/20/1989
• Status: Expired due to Fees

• Current Assignee: Sta-Rite Industries LLC (Pentair Plc (Ireland))
• Original Assignee: Marley Company (SPX Corporation)
• Inventors: Greene, James L.
• Primary Examiner(s): Smith, Leonard E.
• Assistant Examiner(s): Scheuermann, David W.
• Application Number:
  US07/438,802
• Time in Patent Office: 540 Days
• Field of Search: 417/40, 417/44, 320/39, 320/40
• US Class Current: 417/40
• CPC Class Codes: F04B 49/04 Regulating by means of floats F04B49/025 takes precedence
• CPC Class Codes: F04D 13/068 Battery powered
• CPC Class Codes: G05D 9/12 characterised by the use of electric means
• CPC Class Codes: H02J 7/007182 in response to battery voltage

Abstract

A sump pump powered by a rechargeable battery has a circuit for monitoring the battery voltage and controlling charging of the battery. Four comparators monitor the battery and control two flip flops one of which operates the pump in cooperation with a float switch and the other of which turns the battery charging circuit on and off. The circuit is arranged so that when the battery is in its discharge cycle, the float switch controls the pump and the charging circuit comes on only when the battery voltage is in a low range. In the charging cycle, the pump is locked out in a low voltage range of the battery and is controlled by the float switch only in a high voltage range.

Claims

1. Control apparatus for a sump pump having a float switch which assumes first and second conditions, said apparatus comprising:

a rechargeable battery having a charging cycle and a discharge cycle;

means for monitoring the output voltage available from the battery;

means for establishing a low range of said output voltage between a preselected minimum level and a preselected intermediate level and a high range of said output voltage between said intermediate level and a preselected maximum level, aid intermediate level being between said minimum and maximum levels;

a battery charging circuit having a charging mode in which charging current is applied to the battery and an idle mode in which charging current to the battery is discontinued;

means for effecting the idle mode of the charging circuit when said output voltage reaches said maximum level;

means for deenergizing the pump whenever the float switch is in the first condition thereof;

means, effective when the battery is in the discharge cycle with said output voltage in said high range, for effecting the idle mode of the charging circuit and for energizing the pump from the battery when the float switch is in its second condition;

means, effective when the battery is in the discharge cycle with said output voltage in the low range, for energizing the pump from the battery when the float switch is in its second condition and for effecting the charging mode of the charging circuit whenever the pump is deenergized;

means for effecting the charging mode of the charging circuit whenever said output voltage drops to said minimum level;

means, effective when the battery is in the charging cycle with said output voltage in the low range, for maintaining the pump deenergized and for maintaining the charging circuit in the charging mode; and

means, effective when the battery is in the charging cycle with said output voltage in the high range, for energizing the pump from the battery when the float switch is in its second condition and for effecting the charging mode of the charging circuit whenever the pump is deenergized.

2. Apparatus as set forth in claim 1, including a visual indicator and means for activating said indicator when the charging circuit is in the charging mode.

3. Apparatus as set forth in claim 1, including:

a visual indicator for indicating a ready condition of the pump;

means for activating said indicator when the battery is in the discharge cycle and when the battery is in the charging cycle with said output voltage in the high range; and

means for deactivating said indicator when the battery is in the charging cycle with said output voltage in the low range.

4. Apparatus as set forth in claim 1, including:

a visual indicator for indicating when the pump has been energized;

means for activating said indicator when the pump is energized and for maintaining said indicator activated when the pump is deenergized after having been energized; and

manual reset switch means for deactivating said indicator.

5. Apparatus as set forth in claim 1, including manual switch means for energizing the pump from the battery under all conditions of the float switch and charging circuit.

6. In a sump pump having a pump motor, a float switch which assumes first and second conditions and a rechargeable battery for supplying electrical power to the pump motor, the improvement comprising:

a battery charging circuit having a charging mode in which charging current is applied to the battery and an idle mode in which charging current to the battery is discontinued;

means for monitoring the output voltage available from the battery, said charging circuit being in the charging mode whenever said output voltage drops to a preselected minimum level and in the idle mode whenever said output voltage reaches a preselected maximum level;

means for deenergizing the pump motor whenever the float switch is in the first condition and whenever the battery is in a charging cycle with said output voltage in a low range between said minimum level and an intermediate level which is between said minimum and maximum levels;

means for energizing the pump motor from the battery when the float switch is in the second condition and said output voltage is in a high range between said intermediate level and said maximum level, and when the float switch is in the second condition with the battery in a discharge cycle and said output voltage in said low range; and

means for effecting the charging mode of the charging circuit when all conditions except when said output voltage is in said high range with the battery in the discharge cycle, except when the pump is energized with said output voltage in the high range and the battery in the charging cycle, and except when the pump is energized with said output voltage in the low range and the battery in the discharge cycle.

7. The improvement of claim 6, including a visual indicator and means for activating said indicator when the charging circuit is in the charging mode.

8. The improvement of claim 6, including:

a visual indicator for indicating a ready condition of the pump;

means for activating said indicator when the battery is in the discharge cycle and when the battery is in the charging cycle with said output voltage in the high range; and

means for deactivating said indicator when the battery is in the charging cycle with said output voltage in the low range.

9. The improvement of claim 6, including:

a visual indicator for indicating when the pump has been energized;

means for activating said indicator when the pump is energized and for maintaining said indicator activated when the pump is deenergized after having been energized; and

manual reset switch means for deactivating said indicator.

10. The improvement of claim 6, including manual test switch means for energizing the pump motor under all conditions of the float switch and charging circuit.

11. A sump pump comprising:

an electric pump motor;

a rechargeable battery having charging and discharge cycles;

a pump control circuit connecting said battery with said pump motor to energize the latter when completed;

a float switch having a first condition and a second condition, said pump control circuit being interrupted in the first condition of said float switch;

a battery charging circuit having a charging mode in which charging current is applied to the battery and an idle condition in which charging current to the battery is discontinued;

means for monitoring the output voltage available from the battery;

means for effecting the charging mode of said charging circuit when said output voltage drops to a preselected minimum level;

means for effecting the idle mode of said charging circuit when said output voltage reaches a preselected maximum level;

means for establishing a locked out condition of the pump when said charging circuit is in the charging mode to charge the battery from said minimum level and said output voltage is in a low range between said minimum level and a preselected intermediate level which is between the minimum and maximum levels, said pump control circuit being interrupted under both conditions of the float switch when the pump is in the locked out condition;

means for establishing a ready condition of the pump when the pump is not in the locked out condition, said pump control circuit being completed whenever the float switch is in the second condition and the pump is in the ready condition; and

means for effecting the charging mode of the charging circuit under all conditions except when said output voltage reaches said maximum level, except when the battery is discharging in said high range after having been charged to said maximum level, except when the float switch assumes the second condition with said output voltage in the low range and the pump in the ready condition, and except when the float switch assumes the second condition while the battery is being charged in the high range.

12. The pump of claim 11, including a visual indicator and means for activating said indicator when the charging circuit is in the charging mode.

13. The pump of claim 11, including:

a visual indicator for indicating a ready condition of the pump;

means for activating said indicator when the battery is in the discharge cycle and when the battery is in the charging cycle with said output voltage in the high range; and

means for deactivating said indicator when the battery is in the charging cycle with said output voltage in the low range.

14. The pump of claim 11, including:

a visual indicator for indicating when the pump has been energized;

means for activating said indicator when the pump is energized and for maintaining said indicator activated when the pump is deenergized after having been energized; and

manual reset switch means for deactivating said indicator.

15. The pump of claim 11, including manual test switch means for energizing the pump motor under all conditions of the float switch and charging circuit.