Pneumatic pump control system method and apparatus

• US 20020076330A1
• Filed: 09/14/2001
• Published: 06/20/2002
• Est. Priority Date: 09/15/2000
• Status: Active Grant

• Current Assignee: Brian E. Lipscomb, William Carl Garrison
• Original Assignee: Brian E. Lipscomb, William Carl Garrison
• Inventors: Lipscomb, Brian E., Garrison, William Carl
• Granted Patent: US 6,632,072 B2
• Time in Patent Office: Days
• US Class Current: 417/36
• CPC Class Codes: F04D 15/0218 the condition being a liquid level or a lack of liquid supply

Abstract

A pneumatic pump control system for sequentially switching on and off an electrically operated pump disposed in a waste water liquid storage tank The pneumatic pump control system comprises a pneumatic pressure accumulator that is disposed within the liquid storage tank at a predetermined level. The pneumatic pressure accumulator is a dome-type that defines an interior air chamber for containing air, and a lower opening disposed at an elevation that represents a zero reference level within the tank. The lower opening is in communication with the liquids in the liquid storage tank when the level of liquid is as high as the lower opening. A pressure transducer is operatively connected to the pneumatic pressure accumulator for communication with the interior air chamber to measure the differential air pressure between the air within the interior air chamber and the upper layer of air within the liquid storage tank. A first activation means responds to the output signal of the pressure transducer so that the pump is activated for a period of time to discharge a predetermined quantity of liquid. Following this, a clearing activation means responds by activating the pump for a period of time to discharge a predetermined quantity of liquid to lower the liquid level to a level below the zero reference level so that the air captured within the pneumatic pressure accumulator is recharged.

Claims

1. A pneumatic pump control system for controlling the on and off switching of an electrically operated pump disposed in a liquid storage tank, or septic tank provided for receiving waste liquids and solids disposed below an upper layer of air, the pneumatic pump control system comprising:

a pneumatic pressure accumulator disposed at a predetermined level within the liquid storage tank, the pneumatic pressure accumulator defining an interior air chamber for containing air, and a lower opening disposed at an elevation that represents a zero reference level, the air chamber being in communication with the liquids in the liquid storage tank when the level of the liquids are as high as the lower opening;

a pressure transducer operatively connected to the pneumatic pressure accumulator for communication with the interior air chamber thereof to measure the differential air pressure between the air within the interior air chamber and the upper layer of air within the liquid storage tank, wherein the pressure transducer is adapted to generate an electric output signal that corresponds to the differential air pressure;

first activation means responsive to the output signal of the pressure transducer such that when the pressure transducer indicates a pressure that corresponds to a liquid level that has risen above a predetermined start-level elevation within the liquid storage tank, the pump is activated for a period of time to discharge a predetermined quantity of liquid, referred to as a normal dose, wherein at least one normal dose is executed to lower the liquid level to a level at least as low as the start-level elevation; and

clearing activation means responsive to the output signal of the pressure transducer such that when the pressure transducer indicates a pressure that corresponds to a liquid level that is at least as low as the start level elevation, the pump is activated for a period of time to discharge a predetermined quantity of liquid, referred to as a clearing dose, wherein one or more clearing doses are executed to lower the liquid level to a level below the zero reference level so that the lower opening is above the liquid level, and the interior air chamber is in communication with the upper layer of air.

2. A pneumatic pump control system as recited in claim 1 wherein each dose of liquid is equal in volume.

3. A pneumatic pump controller as recited in claim 1 wherein the pressure transducer is disposed outside the liquid storage tank and is communication with the interior air chamber by an elongated tubular member.

4. A pneumatic pump controller as recited in claim 1 wherein the pressure transducer is disposed adjacent the interior air chamber of the pneumatic pressure accumulator.

5. A pneumatic pump controller as recited in claim 4 wherein the pneumatic pressure accumulator comprises an accumulator dome defining an upper end cap, and a coupling collar that extends upward from the upper end cap to define a void for receiving the pressure transducer, wherein the pressure transducer is disposed within the coupling collar for communication with the interior air chamber.

6. A pneumatic pump controller as recited in claim 5 wherein the upper end cap of the pneumatic pressure accumulator defines an opening, and the pressure transducer comprises an air conduit disposed through the opening to allow communication between the pressure transducer and the interior air chamber.

7. A pneumatic pump controller as recited in claim 6 wherein the coupling collar further comprises resin disposed to fill the void defined by the coupling collar thereby encapsulated the pressure transducer within the resin.

8. A pneumatic pump controller as recited in claim 5 wherein the coupling collar further comprises resin disposed to fill the void defined by the coupling collar thereby encapsulated the pressure transducer within the resin.

9. A method of making a pneumatic pump control system for controlling the on and off switching of an electrically operated pump disposed in a liquid storage tank provided for receiving waste liquids and solids disposed below an upper layer of air, the method comprising the steps:

fixing a pneumatic pressure accumulator at a predetermined level within the liquid storage tank, the pneumatic pressure accumulator defining an interior air chamber for containing air, and a lower opening disposed at an elevation that represents a zero reference level, the air chamber being in communication with the liquids in the liquid storage tank when the level of the liquids are as high as the lower opening;

connecting a pressure transducer to the pneumatic pressure accumulator for communication therebetween to measure the differential air pressure between the air within the interior air chamber and the upper layer of air within the liquid storage tank, wherein the pressure transducer is adapted to generate an electric output signal that corresponds to the differential air pressure;

providing a first activation means responsive to the output signal of the pressure transducer such that when the pressure transducer indicates a pressure that corresponds to a liquid level that has risen above a predetermined start-level elevation within the liquid storage tank, the pump is activated for a period of time to discharge a predetermined quantity of liquid, referred to as a normal dose, wherein at least one normal doses is executed to lower the liquid level to a level at least as low as the start-level elevation; and

providing a clearing activation means responsive to the output signal of the pressure transducer such that when the pressure transducer indicates a pressure that corresponds to a liquid level that is at least as low as the start level elevation, the pump is activated for a period of time to discharge a predetermined quantity of liquid, referred to as a clearing dose, wherein one or more clearing doses are executed to lower the liquid level to a level below the zero reference level so that the lower opening is above the liquid level, and the interior air chamber is in communication with the upper layer of air.

10. A method of making a pneumatic pump control system as recited in claim 9 wherein each dose of liquid is equal in volume.

11. A method of making pneumatic pump controller as recited in claim 9 further comprising the steps locating the pressure transducer outside the liquid storage tank and providing an elongated tubular member to facilitate communication between the pressure transducer and the interior air chamber.

12. A method of making pneumatic pump controller as recited in claim 9 further comprising the step of locating the pressure transducer adjacent the interior air chamber of the pneumatic pressure accumulator.

13. A method of making pneumatic pump controller as recited in claim 12 wherein the pneumatic pressure accumulator comprises an accumulator dome defining an upper end cap, and a coupling collar that extends upward from the upper end cap to define a void for receiving the pressure transducer, wherein the pressure transducer is disposed within the coupling collar for communication with the interior air chamber.

14. A method of making pneumatic pump controller as recited in claim 13 wherein the upper end cap of the pneumatic pressure accumulator defines an opening, and the pressure transducer comprises an air conduit disposed pg,34 through the opening to allow communication between the pressure transducer and the interior air chamber.

15. A method of making pneumatic pump controller as recited in claim 14 further comprising the step of placing resin in the coupling collar to fill the void defined by the coupling collar thereby encapsulated the pressure transducer within the resin.

16. A method of making pneumatic pump controller as recited in claim 13 further comprising the step of placing resin in the coupling collar to fill the void defined by the coupling collar thereby encapsulated the pressure transducer within the resin.