Abstract: A pressure relief port for relieving the pressure within an enclosure having a wall with first and second sides and a first opening therethrough. The pressure relief port includes a tube having a conduit therethrough sized to fit in the first opening in the wall to extend essentially intermediate the first and second sides of the wall. First and second end caps having respective openings therein are sized to fit on the first and second walls respectively, about the first opening. The tube extends into the first and second end caps. A flexible diaphragm extends substantially across the conduit in the tube for regulating air flow and is displaceable between a first position where the diaphragm substantially closes off the conduit to air flow and a second position where the diaphragm is displaced by air pressure to permit air to flow through the conduit to equalize pressure on opposite sides of the wall.

Abstract: A shielded vent port for equilization of the pressure on opposed faces of a wall comprises a frame for fitting into an opening in said wall, a conduit through said frame, a sloping plate in said conduit, said plate being sealed against the walls of said conduit and having a large aperture therethrough, and a riser lying against the upper face of said sloping plate, said riser preventing flow of air in a downward direction through said plate and being movable away from said plate to permit flow therethrough in an upward direction. To provide for flow of air through said wall in either direction, the frame may have two conduits therethrough with a sloping plate and a fitted riser in each, the planes of said plates sloping in opposed directions. The shield may be lifted away from the plate to permit flow of air therethrough by an excess of pressure below the plate or by a solenoid in response to an external signal.

Abstract: An edgemounted latch mechanism that is tamper-resistant is provided. An internal locking mechanism is adapted to lock simultaneously both a locking arm and a catch assembly. The catch assembly is constantly forced against a keeper member to assure a constant seal of the door to its gasket or door frame. The mechanism has provision for insertion of an external lock such as a padlock in order to secure the handle with respect to the latch housing and with respect to the locking arm.

Abstract: A self-closing hinge with a concealed switch is provided. The hinge has a cam follower formed on a movable member which rides on a cam formed in a stationary member, causing the movable member to move up and down with respect to the stationary member, as the movable member is pivoted about on axis defined by the stationary member. An actuator button mounted in the stationary member abuts a projection on the movable member at a predetermined position of the movable member for actuating a switch assembly concealed within the stationary member. The switch assembly may be used to activate a variety of circuits.

Abstract: A hinge having stationary and turnable components which respectively carry cams which cooperate with each other to displace the turnable component upwardly with respect to the stationary component during opening movement while permitting the turnable component to move downwardly with respect to the stationary component during closing movement. In addition, a spring structure acts on the turnable component to urge the latter to carry out its closing movement with respect to the stationary component.

Abstract: A roller assembly includes a base plate having an opening, a tubular outer race member formed of polymeric resin and a coaxial tubular inner race member formed of metal. The outer race member is open at its distal end and is provided with an annular proximal end wall adjacent the base plate having its central opening coaxial with the base plate opening and a forwardly directed lip along its inner front border. The inner race member has a distal flange registering with the outer race member distal end and a tubular proximal section projecting through the end wall and base plate openings and having its end upset into engagement with the rear borders of the base plate opening.