Abstract: A filtering apparatus is provided wherein the filter can be backwashed by an explosive-like surge of backwashing fluid. The backwashing assembly includes a quick-opening backwash valve which is not actuated by a linearly-acting valve stem disposed on the outlet side of the valve. In a typical embodiment, the inlet valve to the filtering apparatus is a rotating butterfly valve and the backwash valve is physically attached to the inlet valve, such that, when the inlet valve is open, the backwash valve is fully-closed and when the inlet valve is moved towards its fully-closed position, the backwash valve is fully-opened. The invention uses a two-step method of initially applying biasing pressure on the inlet valve/backwash valve combination and to thereafter provide additional pressure to dislodge the backwash valve from the valve seat--whereupon the backwash valve quickly opens and an explosive-like surge of backwashing fluid effectively backwashes the filtering media.

Abstract: An improved high volume, straight through, low turbulent flow pressure regulating valve is provided by utilizing a hallow cylindrical valve which is selectively and telescopically disposed over an aligned conforming biscuit around which biscuit and through which valve the fluid flows. The valve does not contact the biscuit so that valve chatter is impossible. Furthermore, the absence of a valve seat or other lip reduces the turbulence introduced into fluid flow within the valve body thereby also increasing flow volume capacity. Movement of the valve is controlled in response to pressure within the valve body by means of rolling diaphragm, which is fluidically communicated to the interior of the valve body. The diaphragm, which acts as a piston, is connected between the valve body and the valve member. Increased pressure within the valve acts against the diaphragm forcing the valve member over the biscuit to reduce flow and pressure. The diaphragm, acting as a piston, acts against a prebiased spring.

Abstract: Filtering apparatus in which a fluid filter has a filtering flow passage with an inlet end connected to an inlet control valve, and an outlet end connected with an outlet control valve, said filter having a fluid storage reservoir in communication with the outlet end of the flow passage so that by closing the outlet valve and opening the inlet valve clean filtered fluid may be forced into the reservoir in a manner to compress the entrapped air and provide a supply of pressurized clean filtered fluid for use in a backwashing reverse flow operation through the filtering flow passage, during which the inlet and outlet valves are both closed.The backwash flow is controlled by a unique quick-opening backwash poppet valve which is so connected with the flow passage that the fluid pressure of the backwashing fluid will act to normally urge the backwash valve to a closed position which prevents the reverse flow until the backwash poppet valve is opened.

Abstract: A method of permanently uniting two cylindrical members with mating end edges which cooperate to define a circumferential groove that is closed except for a continuous inner circumferential slot defined by the end edges. In the method, the mating end edges of the two members are brought together to imprison the peripheral bead of a flexible diaphragm under axial compression in the circumferential groove so that the web of the diaphragm extends through the continuous circumferential slot. The two cylindrical members are then held together under pressure while a cap with a cylindrical skirt is telescoped onto one member past the joint between its mating edge and that of the other member. Prior to this telescoping step, the inner wall of the skirt is coated with a suitable adhesive to provide an adhesive layer between the confronting skirt and cylindrical wall areas of the final assembly. The two cylindrical members are maintained under pressure until the adhesive sets, after which the pressure is released.