Patent ID: 6382933
Filing Date: 2002-05-07
Classification: F04B

Abstract:
A bladder-type fluid-actuated liquid pump adapted to be at least partially submerged in a liquid to be pumped, said pump comprising:a hollow casing adapted to be immersed in the liquid, said casing having an upper end and a lower end; a liquid inlet in said lower end; a liquid outlet port in said upper end; a fluid communication port in said upper end; a fluid chamber inside said hollow casing for receiving a fluid under pressure therein, said fluid chamber being in fluid communication with said fluid communication port; a liquid chamber inside said hollow casing for receiving the liquid therein, said liquid chamber being in fluid communication with said liquid inlet and said liquid outlet; a flexible bladder separating said fluid chamber from said liquid chamber, said bladder being selectively deformable in response to changes in pressure of the fluid in order to cause the liquid to flow through said liquid chamber from said inlet to said outlet; an inlet cone-shaped check valve between said liquid inlet and said liquid chamber for permitting one-way flow of the liquid therethrough from said inlet to said liquid chamber and for preventing back-flow of the liquid from said liquid chamber to said liquid inlet; an outlet cone-shaped check valve between said liquid outlet and said liquid chamber for permitting one-way flow of the liquid therethrough from said liquid chamber to said outlet and for preventing back-flow of the liquid from said outlet to said liquid chamber; a top cap disposed at the upper end of said casing, said top cap including said fluid port fluidly connected to said fluid chamber and said liquid outlet port; a top bladder mandrel secured to said top cap, said top bladder mandrel having a communication passage therethrough for fluidly connecting said liquid chamber to said liquid outlet port in said top cap; a bottom cap disposed at the lower end of said casing, said bottom cap having an inlet liquid passage fluidly connected to said liquid inlet; a bottom bladder mandrel secured to said bottom cap, said bottom bladder mandrel having a communication passage therethrough for fluidly connecting said liquid chamber to said inlet liquid passage in said bottom cap, and a support member extending between said top and bottom mandrel inside said bladder, wherein said bladder being sealingly secured to said top bladder mandrel at one end and to said bottom bladder mandrel at the other end, and wherein said liquid chamber is enclosed within said flexible bladder.