Abstract: One embodiment of the present invention provides a poppet valve offering an increased valve area, comprising an outer valve head having an outer valve port and an inner valve head having an inner valve port. The inner valve head is rotatable relative to the outer valve head to align the inner and outer valve ports, thereby increasing the effective valve area of the poppet valve. The path created by aligning the inner and outer valve ports can be designed to mix air flowing through the poppet valve. Another embodiment of the present invention provides a valve guide containing a poppet valve having a guide pin, wherein the guide pin rests within a groove in the valve guide. As the poppet valve moves through the valve guide, the groove controls movement of the guide pin and causes the poppet valve to rotate relative to the valve guide.

Abstract: One embodiment of the present invention provides a poppet valve offering an increased valve area, comprising an outer valve head having an outer valve port and an inner valve head having an inner valve port. The inner valve head is rotatable relative to the outer valve head to align the inner and outer valve ports, thereby increasing the effective valve area of the poppet valve. The path created by aligning the inner and outer valve ports can be designed to mix air flowing through the poppet valve. Another embodiment of the present invention provides a valve guide containing a poppet valve having a guide pin, wherein the guide pin rests within a groove in the valve guide. As the poppet valve moves through the valve guide, the groove controls movement of the guide pin and causes the poppet valve to rotate relative to the valve guide.

Abstract: A mail receptacle system incorporating multiple individually accessible discrete storage compartments disposed within a frame structure with lockable user access doors disposed in mated hinging relation relative to the frame structure such that when the access doors are in a closed position, a male/female relation is established between portions of the doors and the frame structure. The access doors utilize a multi-piece construction wherein the hinging edges of the doors are displaceable from the door body thereby permitting the door body to be easily and readily replace in the event of damage.

Abstract: A spring biased pivot assembly for operative connection across a lower edge of a self-returning door structure. An adjustable spacer projects outwardly from a downwardly extending shoulder structure and towards a tension pin in tangential relation to the axis of rotation. The spacer contacts the tension pin when the door structure is in its normal position thereby maintaining separation between the tension pin and the shoulder structure and blocking complete release of spring tension.

Abstract: Gravity hinge assembly which does not rely upon an axial rod or pintle to maintain axial alignment between the cam cylinders. The assembly incorporates an inter-connective attachment arrangement between the upper rotating cam cylinder and the door connection plate to form a simplified operative connection between the door and the upper cam cylinder while maintaining axial stability.

Abstract: A spring hinge including a pair of hinge leaves having hollow knuckles on adjacent hinges which are arranged in substantially axial alignment such that the hollow knuckles comprise segments of a hinge barrel. A torsion spring made up of a resilient coiled spring member is housed within the hinge barrel. First and second pintles are disposed at opposing ends of the hinge barrel and extend into and between axially aligned knuckles of the hinge leaves. The first and second pintles each engaging the spring member in a locked arrangement such that the spring member extends in a substantially locked relation between the first and second pintles.