Abstract: A dirty gas inlet configuration for a cyclone-type particulate matter gas separator device has two annular concentrically disposed converging dirty gas channels. The outer annular channel has a plurality of gas flow directing vanes disposed therein to impart a spinning or whirling motion to a dirty gas stream passing into the separator device through the outer annular channel from outside the separator device. The inner annular channel has an adjustable dirty gas inlet for varying the volume rate of flow of dirty gas passing into the separator device through the inner annular channel from outside the separator device. The dirty gas streams exiting the outer and inner annular converging channels are mixed together in an annular mixing chamber located downstream from and coaxially disposed with the outer and inner annular channels. While mixing together, the whirling gas stream from the outer channel imparts a whirling motion to the dirty gas stream from the inner annular channel.

Abstract: A door latch device for securing a door in place closing an opening into an enclosure including an elongated resilient retainer strap having an elongated aperture formed in one end and attachable at its other end to the door, a threaded screw-type fastener with a shoulder formed on its shank having its threaded shank extending through the elongated aperture with the shoulder in abutment with one side of the retainer strap, and a latch plate having a concave depression with a centrally disposed threaded aperture therethrough to receive the threaded shank of the screw-type fastener. The screw-type fastener is held in place in the elongated aperture by a resilient toroidally shaped keeper which fits over the shank of the screw-type fastener on the other side of the retainer strap from the shoulder. The latch plate is attachable to the enclosure adjacent the opening to be closed by the door.

Abstract: A ventilating air filtering and distribution device particularly well suited for installation in the ceiling or walls of an environmentally controlled room which room requires a laminar ventilating air flow. The device includes a plenum structure defining a dirty air plenum chamber, and has a dirty air inlet in one face and a clean air outlet in an opposite face. A pair of damper-diffuser plates are adjustably attached to a support beam disposed proximate the clean air outlet, thus, leaving the dirty air inlet unobstructed with support structure. Additionally, filter media is disposed across the clean air outlet to filter the ventilating air as it exits the plenum structure through the clean air outlet.

Abstract: A multi-zone heating-cooling system having a plurality of reversible cycle air heating and cooling units connected to a closed loop water circulation circuit, and at least one ventilating air tempering coil in liquid flow communication with the water flowing in the closed loop water circulation circuit and in heat exchange relationship with a stream of outdoor air such as might be used for ventilation.

Abstract: A filter hood device containing a gas treating filter and having a clean gas outlet aperture which is closed by a blank diffuser mounting panel. The blank diffuser mounting panel is adapted to be modified at a jobsite to receive a diffuser which is suitable for the requirements of that jobsite.

Abstract: An air filter unit to be installed in the wall of an air conveying conduit for filtering air as it passes between the conduit and a room includes a frame to mount a flow-through filter over an appropriate aperture in the conduit wall, a gasket between the filter and frame, a gasket between the frame and interior surface of the conduit wall, a frame collar disposed around the periphery of the frame, a clamp which causes the frame and collar to coact in a vice-like manner forcing the frame against the interior wall surface of the duct compressing the gasket therebetween, and a clamp for holding the filter in the frame. The filter unit may further include a pivotally mounted extractor plate disposed inside the conduit to selectively direct a predetermined amount of air through the filter.

Abstract: A control circuit for an automatic roll-type air filter including a photocell for detecting the dust load condition of the filter media and for energizing the circuit to cause the filter media to advance in response to the dust loading, a variable resistor to provide adjustment of the set-point at which the circuit is energized, and a fixed value resistor in series with the variable resistor to prevent setting of the variable resistor to a value which would allow the circuit to be energized thereby advancing the filter media when cleaned media is present in the air filter zone of the automatic roll-type air filter.

Abstract: An air filtering and distribution structure for an environmentally controlled enclosure, such as clean room, has a first planar surface having a mixed array of filter panels and blank panels spaced from a surface of the enclosure defining a dirty air plenum therebetween, and a second planar section of perforated air diffusing panels spaced from the first planar panel defining a clean air plenum therebetween.

Abstract: A coiled latch for locating and holding a filter in a housing has two coaxially disposed turns preferably in the form of a conical helix, the smaller of the turns exerts a force on the filter holding it into the housing, while the larger of the turns abuts the peripheral margin of the filter to center it in the housing.

Abstract: A ventilating screen for window openings of motor vehicle passenger compartments which provides for the circulation of fresh air into the passenger compartment while the motor vehicle is stopped and moving. The ventilating screen allows the window to be closed completely or partially while still in place in the window opening in the event of inclement weather, and to adjust the amount of air flow. Further, the ventilation screen is easily removable from the window opening with the window either open or closed. The method for fitting the screen to particular window openings provides for its universal application in vertually any motor vehicle, and the method of installing it in the vehicle window opening obviates any modification to the motor vehicle structure.

Abstract: A chuck key storage apparatus for use with a drilling machine for conveniently storing a chuck key. The apparatus, and thus the chuck key, is movable between a stored position and a functional position. In the stored position, the chuck key is positioned remote from a chuck of the drilling machine, and in the functional position the chuck key is located to engage the chuck.

Abstract: A perforated floor panel for use in the construction of a floor for a "clean room" having a return air system, and the like, which provides a controlled constant balanced pressure drop across the floor and a roughing filtration of air passing through it, the floor panel comprising a perforated floor pan, a balancing pad, and a balancing pad retainer which holds the balancing pad in position against the bottom surface of the floor pan.

Abstract: A filter pleat fold spacer for use in a gas filter device of the type having a flow-through filter frame and a pleated filter media disposed within the frame to hold the pleats of the filter media apart when subjected to the flow of gas to be filtered, the pleat spacer being formed to provide a yieldable surface adjacent the pleat fold turns of the media.

Abstract: An air quality sensing apparatus for measuring, monitoring and controlling temperature and air relative humidity of air interior a room, including an apertured housing enclosing temperature and humidity sensing devices and an asperating tube fluidly interconnecting the interior of the housing and a return air system.