Abstract: A double-diaphragm bladder. The bladder comprises a non-flexible diaphragm having a peripheral edge and a flexible diaphragm having a peripheral edge. The non-flexible diaphragm has an aperture adapted and constructed to be connected to a liquid port, and the peripheral edges of the non-flexible diaphragm and the flexible diaphragm are sealed together. The bladder is suitable for use in an expansion tank.

Abstract: An in-line expansion tank. As fluid traverses a pipe within the tank, it may pass into and displace a diaphragm disposed outside of the pipe if the fluid pressure is greater than a tank pressure pushing the diaphragm against the pipe. When the fluid pressure decreases, the fluid passes from the diaphragm back into the pipe.

Abstract: A pressure maintenance assembly for a domestic water well system. The assembly comprises a pressure maintenance valve having an inlet side and an outlet side, a pressure tank in fluidic communication with the outlet side, and a calibrated bypass. When the valve is closed, the calibrated bypass provides fluidic communication between the inlet side and the outlet side. The size of the calibrated bypass and the pressure tank are adapted and constructed to permit a flow rate between the inlet side and the outlet side that will fill the pressure tank in a time interval less than twice the time required to pump a volume of water that will dissipate heat generated by the pump when it is turned on.

Abstract: A pressure maintenance assembly for a domestic water well system. The assembly includes a pressure maintenance valve having an inlet side and an outlet side, a pressure tank in fluidic communication with the outlet side, and a calibrated bypass. When the valve is closed, the calibrated bypass provides fluidic communication between the inlet side and the outlet side. The size of the calibrated bypass and the pressure tank are adapted and constructed to permit a flow rate between the inlet side and the outlet side that will fill the pressure tank in a time interval at least as great as but less than twice the time required to pump a volume of water that will dissipate heat generated by the pump when it is turned on.

Abstract: Hydraulic actuator. An actuator body includes an inlet, an outlet, a port communicating with a pre-charged diaphragm tank, and a port communicating with a pressure switch. The actuator body includes a movable member which, in a first position, closes the inlet port and provides fluidic communication with the pressure switch port while allowing pressure equalization between the inlet and an interior of the actuator body. In a second position, the movable body opens the inlet port and seals the pressure switch port. A spring is disposed within the actuator body to urge the movable member toward the first position. The invention eliminates the need for multiple springs as shown in one prior art design and eliminates the need for reliance on a hydrostatic force differential to move the movable member.

Abstract: Hydraulic actuator. An actuator body includes an inlet, an outlet, a port communicating with a pre-charged diaphragm tank, and a port communicating with a pressure switch. The actuator body includes a movable member which, in a first position, closes the inlet port and provides fluidic communication with the pressure switch port while allowing pressure equalization between the inlet and an interior of the actuator body. In a second position, the movable body opens the inlet port and seals the pressure switch port. A spring is disposed within the actuator body to urge the movable member toward the first position. The invention eliminates the need for multiple springs as shown in one prior art design and eliminates the need for reliance on a hydrostatic force differential to move the movable member.

Abstract: Hydraulic actuator. An actuator body includes an inlet, an outlet, a port communicating with a pre-charged diaphragm tank, and a port communicating with a pressure switch. The actuator body includes a movable member which, in a first position, seals the inlet port and provides fluidic communication with the pressure switch port. In a second position, the movable body opens the inlet port and seals the pressure switch port. A spring is disposed within the actuator body to urge the movable member toward the first position. The invention eliminates the need for multiple springs as shown in one prior art design and eliminates the need for reliance on a hydrostatic force differential to move the movable member.