Abstract: A solenoid valve useful in a slip-controlled hydraulic brake system of a motor vehicle, and which has a seat valve disposed between a pressure fluid inlet and a pressure fluid outlet and in the bypass to the seat valve has a check valve with a quad ring as a closing body and a circular ring surface as a valve seat. Circularly disposed pressure fluid openings adjoin the circular ring surface and are overlapped on the radial inside and on the radial outside by respective sealing lips of the annular rubber-elastic closing body, which is guided with axial motion play in relation to the circular ring surface.

Abstract: An improved liquid fertilizer distribution manifold operating in two stages. An accumulator piston located above the primary and secondary ports provides for two stages of flow. A broad range of regulated flow for site-specific farming results in precise, accurate and timely application of liquid fertilizer and pesticides. An elevated piston seal flange in the manifold allows flow to be exact with plugged or partially plugged primary orifices. Manifolds are produced in single tier and double tier arrangements to improve efficiency. The same manifold can be applied to NH3 pressure increasing systems. NH3 pressure decreasing systems and liquid fertilizer and pesticide systems.

Abstract: A circulating valve and associated methods of using same provide control of fluid flow within a subterranean well. In a described embodiment, a circulating valve includes a fluid pressure storage chamber in fluid communication with the exterior of the valve. When positioned in a wellbore, fluid pressure in an annulus between the valve and the wellbore is stored in the storage chamber. A subsequent, relatively rapid, increase in the annulus fluid pressure causes the valve to operate.

Abstract: A water system uses a pressure reservoir of an extremely small size. A valve device is placed between a water pump and the pressure reservoir. The valve device has a constant outlet pressure to limit the flow from the pump at high pressures. The pump is turned on and off by a pressure on/off switch. The valve device maintains the pressure to the reservoir at or below the on switch pressure except for a trickle flow. The trickle flow fills the reservoir when there is little or no water usage from the reservoir. The trickle flow is achieved by a notch in the valve surfaces of the valve device or by a projection preventing the surfaces to seal. Each time the valve opens any debris in the notch is washed from the notch thereby keeping the notch free of debris. Back flow of the trickle is prevented with a roll seal valve by restricting the trickle to a flow path and incorporating a check valve in the flow path.