Automatic sub-floor pumping system

• US 5,923,102 A
• Filed: 04/20/1998
• Issued: 07/13/1999
• Est. Priority Date: 04/20/1998
• Status: Expired due to Fees

• Current Assignee: Tom R. Koenig
• Original Assignee: Avcheck Corporation
• Inventors: Koenig, Robert H., Koenig, Richard E.
• Primary Examiner(s): PALADINI, ALBERT WILLIAM
• Application Number:
  US09/062,845
• Time in Patent Office: 449 Days
• Field of Search: 307/118, 340/602, 340/604, 340/618, 340/620, 361/178, 417/19, 417/20, 417/279, 73/53.04, 73/304 R
• US Class Current: 307/118
• CPC Class Codes: G01F 23/242 Mounting arrangements for electrodes
• CPC Class Codes: G01F 23/243 Schematic arrangements of probes combined with measuring circuits

Abstract

An automatic sub-floor pumping system, having a controller box, sensor wires, suction hose and pump. Two or three sensor probes are used--the lowest, or ground, probe can be omitted, and the circuit referenced to earth or wiring ground. The pump evacuates water from beneath the basement floor through a hose inserted into a small hole drilled into the basement floor. The sensor probes can be simply wires with the last 1/8" to 1/2" bared, attached to the outside of the pump suction hose at two locations an inch or two apart. The hose, with wires attached, is inserted down the one-inch evacuation hole bored through the floor. The control uses a very low current on the wires, which are negative relative to ground so as to be cathodically protected from corrosion. An optional sensing circuit monitors lower probe wire voltage and warns of possible corrosion effects.

Claims

1. A pump control device for controlling water level in a recess between a highest and a lowest desired water level by controlling a pump, comprising:

a) an electrically conductive lower probe located in the recess at a first location representing the lowest desired water level;

b) an electrically conductive upper probe located in the recess at a second location representing the highest desired water;

c) a controller comprising;

i) a ground connection having a positive voltage applied thereto, such that a positive voltage is applied to any water in the recess;

ii) a first sensor circuit having an input coupled to the lower probe and an output having a voltage, the circuit being selected such that the voltage on the output changes from a first voltage when no voltage is detected on the input to a second voltage when a selected voltage is detected on the input indicating the presence of water on the lower probe, the input of the first sensor circuit being selected such that the current through the probe is small when the probe is in water;

iii) a second sensor circuit having an input coupled to the upper probe and an output having a voltage, the circuit being selected such that the voltage on the output changes from a first voltage when no voltage is detected on the input to a second voltage when a selected voltage is detected on the input indicating the presence of water at the upper probe, the input of the first sensor circuit being selected such that the current through the probe is small when the probe is in water;

iv) a logic circuit having a first input coupled to the output of the first sensor circuit and a second input coupled to the output of the second sensor circuit, and an output having a voltage, the circuit being selected such that the voltage on the output is initially at a first voltage level, switches to a second voltage level when the output of the second sensor circuit changes to the second voltage, and remains in the second voltage level until the output of the first sensor circuit changes from the second voltage to the first voltage;

v) a pump control output, having an input coupled to the output of the logic circuit, and an output for controlling a pump, such that the pump is turned on when the output of the logic circuit is at the second voltage, and is off when the output of the logic circuit is at the first voltage;

the input to the first sensor circuit and input to the second sensor circuit of the controller being at a voltage which is lower than the positive voltage applied to the ground connection, such that the upper probe and lower probe are kept at a negative voltage relative to the water.

2. The pump control device of claim 1, in which the ground connection is an electrically conductive third probe, located in the recess at a position lower than the lower probe.

3. The pump control device of claim 1, in which the ground connection is an earth ground.

4. The pump control device of claim 1 in which the first sensor circuit and second sensor circuit comprise bipolar transistors.

5. The pump control device of claim 1, further comprising an indicator light coupled to the output of the first sensor circuit.

6. The pump control device of claim 1, in which the first sensor circuit and second sensor circuit comprise field effect transistors.

7. The pump control device of claim 6 in which the field effect transistors are MOSFET devices.

8. The pump control device of claim 1, in which the controller further comprises a detection circuit comprising:

a voltage reference having an output voltage, selected to be negative relative to the voltage applied to the ground connection and positive relative to the voltage on the input to the first sensor circuit;

a comparator having a first input coupled to the lower probe and a second input coupled to the voltage reference output voltage, and an output, the output changing from a first state when the voltage on the lower probe is greater than the voltage reference output voltage to a second state when the voltage on the lower probe is less than the voltage reference output voltage;

an indicator driver circuit coupled to an indicator, having an input coupled to the output of the comparator such that the indicator is driven to give a preselected indication when the output of the comparator is in the second state.

9. The pump control device of claim 8, in which the indicator driver circuit comprises a timer, the indicator comprises a light, and the preselected indication is the flashing of the light.

10. The pump control device of claim 9, in which the timer further comprises a second input coupled to the output of the first sensor circuit, and the output of the timer turns the light on when the output of the first sensor circuit indicates the lower probe is in the water, and the timer causes the light to flash when the output of the comparator is in the second state.

11. The pump control device of claim 1, in which the recess is a hole drilled in a basement floor.

12. The pump control device of claim 11, in which the pump has an input hose inserted in the hole.

13. The pump control device of claim 12, in which the upper probe and lower probe are the stripped ends of wires attached to the hose.