Submersible pneumatic pump with air exclusion valve

A pneumatically driven canister liquid pump that prevents compressed air from accompanying discharged liquid, comprising:

• a. a sealed casing having upper and lower ends with an interior volume into which exterior liquid to be pumped can enter and from which interior liquid to be discharged can be pumped;
• b. at least one discharge pipe in liquid connection to said sealed casing, said discharge pipe having an interior liquid passage, an upper end and a lower end for conveying said interior liquid from the interior volume of said sealed casing;
• c. at least one inlet check valve for allowing said exterior liquid into said sealed casing and preventing said interior liquid from flowing out of said sealed casing;
• d. at least one discharge check valve for allowing said interior liquid out of said sealed casing and preventing discharged liquid from flowing into said casing;
• e. at least one passage through a wall of said sealed casing for allowing compressed air (a) into said sealed casing to pressurize the interior of said sealed casing, and (b) out of said sealed casing to exhaust the interior of said sealed casing;
• f. at least one air exclusion valve in fluid connection with said discharge pipe for preventing said compressed air from flowing out of said sealed casing through said discharge pipe-and into said discharged liquid;
• and,
• g. piping between said air exclusion valve and said discharge pipe through which said interior liquid can pass,
• whereby when said sealed casing is submerged in said exterior liquid and said compressed air is alternately allowed out of the interior of said sealed casing to exhaust said sealed casing and into said sealed casing to pressurize the interior of said sealed casing, (a) said exterior liquid passes into said casing through said inlet check valve and said interior liquid is pumped out of said sealed casing via said discharge pipe and said discharge check valve, and (b) said compressed air is prevented from being transmitted out of said sealed casing through said discharge pipe and said discharge check valve into said discharged liquid.

A pump and pump control for pumping liquid comprising,

• a. a sealed casing having upper and lower ends with an internal volume;
• b. inlet check valve means for allowing exterior liquid to be pumped to flow into said sealed casing, and preventing interior liquid to be discharged from said sealed casing from flowing out of said sealed casing;
• c. an outlet check valve means for allowing said interior liquid to be pumped out of said casing through a discharge pipe and prevent discharged liquid from flowing into said casing;
• d. a sealing float of lower density than said interior liquid to be discharged;
• e. a sealing seat for said sealing float;
• f. a liquid connection between said sealing seat and said discharge pipe for allowing flow of said interior liquid to be discharged between said sealing seat and said discharge pipe;
• g. third valve means for allowing compressed air into said sealed casing to pressurize said internal volume of said sealed casing;
• h. fourth valve means for exhausting said compressed air out of said internal volume of said sealed casing;
• i. pressurization and depressurization means for alternately pressurizing and exhausting said internal volume of said sealed casing with said compressed air;
• whereby said exterior liquid to be pumped is alternately allowed into said sealed casing and said interior liquid to be discharged is forced out of said sealed casing through said discharge pipe using said compressed air without allowing said compressed air to exit said pump via said discharge pipe.

A pump and pump control comprising,

• a. a sealed casing having upper and lower ends;
• b. an inlet check valve in fluid connection between the interior of said sealed casing and the exterior of said sealed casing for allowing liquid to be pumped to flow into said sealed casing through said inlet check valve and prevent interior liquid to be discharged from flowing out of said inlet check valve;
• c. a discharge pipe having an exterior end and interior end with said exterior end being exterior to said sealed casing and said interior end being interior to said sealed casing;
• d. an outlet check valve for allowing said interior liquid to flow out said sealed casing and not allow discharged liquid to flow into said sealed casing through said outlet check valve;
• e. a first float of lower density than said interior liquid;
• f. a sealing seat for said first float located internally of said sealed casing and near said lower end of said sealed casing;
• g. piping in liquid connection between said sealing seat and said discharge pipe;
• h. means for allowing compressed air into the interior of said sealed casing;
• i. means for exhausting said compressed air out of said interior of said sealed casing;
• j. a second float of lesser density than said interior liquid that is raised to said upper area of said sealed casing as the level of said interior liquid rises inside of said sealed casing;
• k. a switch located near said upper end of said sealed casing;
• l. means, connected to said second float, for operating said switch when said second float is in proximity to said switch;
• m. at least one valve responsive to the operation of said switch causing compressed air to pass into said sealed casing to pressurize said sealed casing and cause said interior liquid to flow through said sealing seat, through said discharge pipe and out of said sealed casing;
• n. a preset pressure sensing means for causing said compressed air to be exhausted from said sealed casing and for allowing said liquid to be pumped to enter said sealed casing;
• whereby when said pump is submerged in said liquid to be pumped, said liquid to be pumped is allowed into said sealed casing, and said interior liquid rises near said upper area of said sealed casing moving said second float in proximity with the upper end of said sealed casing and in proximity to said switch, causing said compressed air to enter into said sealed casing, thereby forcing said interior liquid to flow through said discharge pipe and out of said sealed casing and subsequently to begin an exhaust cycle of said pump when the falling level of said interior liquid inside said sealed casing causes said first float to rest on said sealing seat causing air pressure in said sealed casing to rise above the preset pressure value of said preset pressure sensing means.

A method for pumping liquid comprising:

• a. providing a submersible pump submerged in liquid to be pumped, said pump having a sealed casing with first means for allowing said liquid to be pumped into said casing through an entry port, and not allow interior liquid to be discharged out of said casing through the entry port, and second means in liquid connection to a discharge pipe for allowing said interior liquid out of said casing through an exit port, and not allow discharged liquid into said casing through the exit port, said submersible pump having means for preventing compressed air from being discharged from said pump with said interior liquid;
• b. providing a pump control for alternately supplying said compressed gas to said casing and exhausting said compressed gas from said casing to create a pressurization cycle and an exhaust cycle to the interior of said casing;
• c. alternately pressurizing said casing with said compressed gas and exhausting said casing of said compressed gas to alternately force said interior liquid from said casing and after said interior liquid is forced from said casing, allow said liquid to be pumped to again enter said casing;
• whereby said liquid to be pumped is transported from one location to another without allowing said compressed gas to exit said casing via said discharge pipe with said interior liquid.

A method for pumping liquid comprising:

• a. providing a submersible pneumatic canister pump with an interior and exterior and an upper and lower end submerged in exterior liquid, said pump containing a first valve with a first float of lighter density than interior liquid, said first float arranged to seal said first valve when the level of said interior liquid in said pump nears the lower end of said pump so that said first valve prevents air and said interior liquid from leaving said pump, a float-operated switch and a second float, also of lighter density than said interior liquid, having an upper limit of travel and a lower limit of travel so that said second float causes said float-operated switch to operate as said second float travels to and from said upper limit of travel and said lower limit of travel,
• b. sensing the pressure within the interior of said pump
• c. providing a pump control for alternately supplying compressed air to said pump and exhausting said compressed air from the interior of said pump to create a pressurization cycle and an exhaust cycle of the interior of said pump, said pump control arranged to end said pressurization cycle and begin said exhaust cycle when said sensed air pressure inside said pump exceeds a preset value established in said pump control and to end said exhaust cycle and begin said pressure cycle after said second float rises near said upper limit of travel,
• d. alternately pressurizing and exhausting the interior of said pump with compressed air to alternately force said interior liquid from said pump and allow said pump to again fill with said exterior liquid in which said pump is submerged,
• whereby said exterior liquid is pumped from one location to another without allowing compressed air to exit said pump with said interior liquid.

a pump control for operating a submersible canister pump for pumping fluid and having an air exclusion valve comprising:

• a. a compressed air source;
• b. an air pressure regulator set to pass compressed air at a predetermined pressure;
• c. a pump air valve having a sensor,
• d. a pneumatic timer having a sensor reactive to air pressure so that, when pressurized to a predetermined pressure, said timer starts a timer cycle or delay, which, when complete, allows compressed air to pass to the sensor of said pump air valve;
• e. a two-position valve with two independent sensors, each sensor being reactive independently to air pressure and each sensor driving said two-position valve to one of two positions, depending upon which sensor has a greater air pressure applied, so that pressurized air from said regulator drives said two-position valve to a first position, and pressurized air from the interior of said pump drives said two-position valve to a second position, and when said two-position valve is in said first position, it passes air to said pneumatic timer sensor and in said second position it exhausts air from said pneumatic timer sensor;
• and
• f. said pump air valve sensor being reactive to air pressure so that, at a predetermined air pressure from said timer, said pump air valve allows compressed air to pass to the interior of said canister pump and when said pump air valve sensor is depressurized, it exhausts air pressure from the interior of said canister pump,
• said pump air valve being connected to said compressed air source and arranged to be connected to the interior of said canister pump and one of said sensors of said two-position valve, said air pressure regulator being connected between said compressed air source and one of said two sensors of said two-position valve, said timer being connected between said compressed air source and said sensor of said pump air valve, said two-position valve being connected between said compressed air source and said timer sensor,
• whereby when said two-position valve is in said first position said timer sensor is pressurized and said timer cycle commences and compressed air from the interior of said pump is exhausted, allowing said pump to fill with fluid, and when said timer cycle ends, compressed air is passed to the interior of said pump, thus causing said pump to discharge fluid and eventually causing the air pressure inside said pump to rise above the pressure of the air exiting from the regulator, thereby shifting said two-position valve to said second position, exhausting air from said timer sensor and thereby exhausting air from said pump air valve sensor and thus exhausting air from interior of said pump and when the air pressure in said pump is below the air pressure exiting said regulator, said two-position valve shifts back to said first position so that said timer sensor is again pressurized, causing said timer cycle to begin again, allowing said pump to again fill with fluid, thus automatically alternating fill and discharge cycles of said pump.