Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
474 words
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.
Claim 2
Dependent Claim
474 words
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.
Claim 3
Dependent Claim
30 words
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.
Claim 4
Dependent Claim
16 words
The pump control device of claim 1, in which the ground connection is an earth ground.
Claim 5
Dependent Claim
20 words
The pump control device of claim 1 in which the first sensor circuit and second sensor circuit comprise bipolar transistors.
Claim 6
Dependent Claim
21 words
The pump control device of claim 1, further comprising an indicator light coupled to the output of the first sensor circuit.
Claim 7
Dependent Claim
21 words
The pump control device of claim 1, in which the first sensor circuit and second sensor circuit comprise field effect transistors.
Claim 8
Dependent Claim
16 words
The pump control device of claim 6 in which the field effect transistors are MOSFET devices.
Claim 9
Dependent Claim
157 words
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.
Claim 10
Dependent Claim
31 words
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.
Claim 11
Dependent Claim
70 words
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.
Claim 12
Dependent Claim
19 words
The pump control device of claim 1, in which the recess is a hole drilled in a basement floor.
Claim 13
Dependent Claim
19 words
The pump control device of claim 11, in which the pump has an input hose inserted in the hole.
Claim 14
Dependent Claim
25 words
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.