Abstract: A combined heating and air conditioning unit has a condenser for cooling compressed working fluid and an evaporator for expanding the working fluid and to cool it. A centrifugal blower pulls air through the condenser into one side of the blower and pulls cool air through the evaporator into the other side of the blower. A divider in the center of the blower prevents the cool air from the evaporator and warm air from the condenser from mixing. At the output of the blower, a valve is provided at the output and connected to the delivery duct so that warm air from one side of the blower or cold air from the other is delivered to the duct, and the air not delivered to the duct is exhausted to the atmosphere. The valve may also allow some mixing of the warm and cold air.

Abstract: A boiling sensor includes a case, which is mounted on the upper edge of a container in which liquid is to boil. A pair of electrical probes are spaced apart a small distance and mounted on the case above the liquid. Behind the probes is a collector of the material, preferably sheet nylon, which does not absorb the liquid, which is non-wettable and electrical insulative, and which has a high heat capacity. With a high heat capacity, the vapor raises the temperature of the collector slowly so that vapor continues to condense on the collector between the probes. The probes are part of an electrical circuit. The condensed water vapor allows current to flow the between the probes, and the rest of the circuit causes current to flow through a sound or visual indicator to indicate that the water is boiling. This circuit also has a voltage divider, one side of which is the electrical probe, and by adjusting the resistance on the other side of the voltage divider, the sensitivity of the circuit can be controlled.

Abstract: The aircraft pre-ventilation system has a ventilation unit mounted for movement along the ground. A primary and a return duct carry air between the ventilator and the aircraft door opening. The ducts are connected to a fitting which is designed to fit into and seal different size door openings for different aircraft. The fitting has a central rigid member, and a flexible bladder is attached to and surrounds the outside of the central member. The fitting is supporting by an adjustable arm for positioning the fitting in the door opening. When the fitting is properly positioned, the bladder expands to secure and seal the fitting to the aircraft door opening. The support arm that holds the fitting is hollow and carries pressurized air from the ventilator to a hose near the fitting that carries the air into the bladder.

Abstract: A collapsible camper has a container mounted on the top of a pick-up truck cab. The container is formed from a cover having a rear, generally vertically wall and an upper, horizontal wall pivoting to a base. A front wall also pivots with respect to the base between an angled position and a vertical position. A foldable canopy is stored within the container cavity. To deploy the canopy, the cover is pivoted so that the generally vertical portion of the cover extends downward below the base, and the horizontal portion of the cover extends horizontally to act as a shelf, a U-shaped brace mounts between the canopy and the side walls of the pickup truck. A side wall of the container folds downward so that the top surface of the base is wide enough to be a sleeping surface, and its downward pivoting and the upward pivoting of the front wall are accomplished by a single linkage.