Abstract: The rate at which a flow control valve maintains flow under varying pressures can be adjusted by positioning a resilient flow control washer on a valve seat and engaging the opposite surface of the washer with an adjustable member which can be moved toward and away from the valve seat to compress the washer in varying amounts and thereby alter the value at which the washer maintains a constant flow.

Abstract: An early warning system detects the failure of a marine cooling system by monitoring the presence of water within the cooling system so that an alarm is given upon cessation or a severe reduction of water flow therethrough. A water sensing element is inserted within the cooling system preferably within an exhaust system of a marine engine cooled by the cooling system and a detection circuit is connected to the water sensing element. An alarm signal is generated by the detection circuit if insufficient water flow is sensed by the water sensing element. The circuit preferably comprises a darlington amplifier having a power input terminal, a power output terminal and a control terminal. A resistor and a capacitor are connected in parallel between the power input terminal and the control terminal of the darlington amplifier, the water sensing element is connected to the control terminal and an audible or visual or combined audible and visual alarm device is connected to the power output terminal.

Abstract: A valve assembly is disclosed for permitting relatively free flow in a flow path in a first direction and for preventing flow in the path in a second, opposite direction. The assembly includes a resilient flow regulator including a pair of lips arranged in a converging relationship to define a normally closed slit at the outer ends of the lips. An annular flange extends outwardly about the opposite end of the regulator. A housing outlet portion defines a housing interior approximating the shape of the regulator. The housing outlet portion further includes an annular collar disposed outwardly adjacent the base of each planar surface. The regulator is diposed within the housing outlet portion with the flange contained within the collar, and with the lips being adjacent to but not in contact with the interior housing surface. A cover plate is attached to the collar for securing the regulator and for sealing the housing.

Abstract: A valve assembly is disclosed for use within a flow path for permitting relatively free flow in said flow path in a first direction and for preventing flow in said path in a second, opposite direction. The assembly includes a resilient flow regulator including a pair of lips arranged in a converging relationship to define a normally closed slit at the outer ends of the lips. An annular flange extends outwardly about the opposite end of the regulator. A housing outlet portion defines a housing interior approximating the shape of the regulator, having a pair of planar surfaces corresponding to the pair of lips. The housing outlet portion further includes an annular collar disposed outwardly adjacent the base of each planar surface. The regulator is disposed within the housing outlet portion with the flange contained within the collar, with the lips being adjacent to but not in contact with the planar surfaces. A cover plate is attached to the collar for securing the regulator and for sealing the housing.

Abstract: A valve assembly for permitting relatively free flow in a first direction and for preventing flow in a second, opposite direction in a flow path includes a housing having first and second ports and defining a housing interior having an interior surface. A resilient flow regulator includes a pair of lips arranged in a converging relationship to define for the regulator an open end and a normally closed end. At the normally closed end, the lips are disposed adjacent each other to define a normally closed slit therebetween, and to define inner and outer surfaces for the lips. The regulator further includes at least one side wall interconnecting the lips. The regulator is secured within the housing interior so that flow in the first direction is from the first port, through the open end, through the normally closed end, and to the second port.

Abstract: A needle valve is formed by molding a resilient tip to a rigid body having a tip receiving cylindrical portion or barrel which includes tip retaining means for securing the resilient tip thereto. The tip is then ground until the outer edge of the barrel is engaged to form a resilient single angle or simple conical tip to thereby eliminate distortions which may be present in the molded tip. The tip retaining means comprises either a socket formed into the distal end of the barrel or a mushroom-shaped bayonet projection extending therefrom.

Abstract: A bi-directional pressure relief valve includes a cylindrical main body portion defining a flow path through the valve and terminating in an asymmetrical lip portion having a curved contour about an axis of curvature extending perpendicularly to the flow path and a linear contour which is substantially normal to the curved contour. The lip portion has a normally closed slit formed through it and expands to open the slit to permit flow in one direction in response to pressure differentials across the lip portion above a first pressure differential, regains its undeformed shape to close the slit and check flow at pressure differentials below the first differential and above a second pressure differential, and collapses in a predictable and repeatable manner to open the slit to permit flow in an opposite direction at pressure differentials below the second pressure differential.

Abstract: A combination check-overpressure relief valve includes a cylindrical main body portion defining a flow path through the valve and terminating in a curved lip portion having a radius of curvature extending perpendicularly to the flow path. The curved lip portion has a normally closed slit formed through it which opens to flow in one direction but checks flow in an opposite direction until a certain pressure is exceeded, at which the valve relieves to allow flow in the opposite direction. The valve will thereafter automatically reset to its original checking position once the pressure has dropped sufficiently. If desired the pressures at which flow can occur through the valve may be increased by providing the valve with stiffening ribs projecting radially outwardly of the main body portion.

Abstract: A drip irrigation system which includes a flow control valve having an inlet opening which constricts in response to pressure increases to provide a uniform flow despite pressure variations. The inlet opening of the valve has a rectangularly cross-sectioned central section and end sections which are non-rectangular, such as triangular or semi-circular, in cross section. During normal flow conditions the rectangular central section of the inlet opening is pressed closed and irrigation liquid flows at a constant rate through the two end sections.

Abstract: An emitter for use in drip irrigation systems which is both self-purging and pressure responsive to provide substantially constant flow rates with varying inlet pressures. The emitter includes a flow path which consists of a series of interconnected openings in each of which is positioned a valve including a valve lip which extends across the opening in which it is located and is directed in an upstream direction so that as the pressure drop across any one valve increases, the effective area of the flow path at that valve will decrease to maintain a substantially constant flow rate. When the pressure drop at a particular valve increases above a predetermined amount, as when a particle of dirt or other foreign substance clogs the valve, the valve lip travels over center and allows the clogging particle to pass, thereby purging that particular valve and permitting it to return to its normal operating position.

Abstract: A reactive type marine muffler which combines principles of both baffled construction and expansion chamber attenuation with a liquid flow path to provide improved sound attenuation over a broad spectrum of octave bands and a substantially lower dB(A). The baffles are preferably dome-shaped with their apices directed counter to the flow through the muffler and the expansion chambers are interconnected by a connecting tube mounted in a median baffle and projecting into adjoining expansion chambers.