Abstract: A momentary contact switch suitable for use in an electrical keyboard has cylindrical projections projecting from a baseplate with axial bores into which projections of the keys fit and by which are guided and retained. A resilient boot interposed between each key and the baseplate and surrounding the cylindrical projections bears against the underside of the key to keep its switch unclosed except when force is applied to an actuation surface of the key. A movable contact internal to the boot is transported by actuation of the key to make electrical contact with a fixed contact adjacent the cylindrical projection. In a preferred embodiment the fixed and movable contacts both have the shape of a ring and encircle the cylindrical projection. The movable contact in the preferred embodiment further is formed on a resilient surface of the boot.

Abstract: A structure and a device which allow low resistance connections to internal circuit devices comprising a double diffused leadout is described. The first leadout diffusion is lightly doped with dopant from either chemical group III or V to constitute N- or P- type material respectively. The lightly doped region has a high resistivity. The second diffusion is diffused, using a dopant from the same chemical group as the first dopant, into the first diffusion. The second diffusion is diffused with enough dopant to constitute N.sup.+ or P.sup.+ material and has a low resistivity. The double diffused leadout creates a low resistance connection to the internal circuitry of an IC device while maintaining breakdown with the protective overlayer.

Abstract: A system for controlling the operation of an HVAC system which includes a direct expansion coil, a condenser, a pre-cool coil, and a control system. The control system includes a controller and sensors. The controller receives signals indicative of air flow through the direct expansion coil from the sensors, compares the received signal to a stored air flow rate, and disables the compressor if the stored air flow rate is equal to or greater than the stored value. The controller is also adapted to vary air flow into an occupied space for small changes in the cooling load. In addition, the controller can artificially load the compressor during periods of small cooling load by restricting flow of a cooling agent between the cooling tower and the condenser, or by directing warm water from the condenser through the pre-coil coil.

Abstract: A colorimeter provides compensation for changes in the color signature of an object due to lamp aging, stand off distance and view angle changes. The colorimeter senses and stores values indicative of a sample object. In use, the colorimeter senses and creates values indicative of an object. The colorimeter includes a processor which then creates an average ratio wherein the stored values and corresponding sensed values are placed in a ratio, all of the ratios are then summed, and the total is divided by the number of values. Finally, the processor compares the sensed values with corresponding stored values, wherein one of the two values is adjusted by the average ratio.

Abstract: A colorimeter for characterizing the color of an object is placed in an environmentally sealed enclosure for use in industrial environments. In order to maintain an acceptable operating temperature for the colorimeter's electronics and lamp, a heat shield is placed around the lamp to substantially isolate it from the electronics. The heat shield and the environmentally sealed enclosure are made of a highly heat conductive material such as aluminum. The heat shield is thermally coupled to the environmentally sealed enclosure.

Abstract: A colorimeter provides compensation for changes in the color signature of an object due to lamp aging. A current measuring circuit measures current to the lamp during an initial training of the colorimeter and stores a value I.sub.T indicative of the lamp current at training. When an object is scanned by the colorimeter, lamp current is again sensed and assigned a value I.sub.S. Comparison between a sensed color signature and a stored color signature then occurs. Compensation is accomplished by modifying one of the two signatures by a ratio including I.sub.S and I.sub.T.

Abstract: A microcontroller and system allowing for more than one trial time in a furnace system, while using only one pin of the microcontroller. An alternating current signal at an input port of the microcontroller causes the microcontroller to allow a first long trial time period. Any direct current signal at the input port causes the microcontroller to allow only a second shorter trial time period. The trial time input port of the microcontroller is placed between two ports which either receive or send direct current signals. Due to this arrangement of the parts and construction of the microcontroller, the microcontroller will fail to the shorter and safer trial time if a fault causes an erroneous signal to appear at the input port.

Abstract: A layout device for locating a wall mounted item a specified distance from a reference point such as a floor includes a bracket which is removably mounted to a measuring tape. A level attached to the bracket indicates vertical alignment of both the extended tape and the item which is to be installed. The bracket includes protrusions which form indentations marking the measured location when the bracket is forced against the surface of the wall.

Abstract: A structure for an Integrated Injection Logic (I.sup.2 L) gate is disclosed in which gate gain .alpha.*.beta. is improved and leakage current at the silicon-silicon dioxide interface is reduced. A plug of highly doped material is interposed between the emitter and the collector of the lateral transistor to accomplish these goals.

Abstract: A thermostat is disclosed which has a moveable backstop in order to fulfill a requirement in many countries that a 3 millimeter contact gap be provided for the thermostat to qualify as an electrical disconnect. The thermostat is comprised of a setting wheel having a ramp formed thereon, a lever, a plunger and a backstop slidably connected to the frame of the thermostat. The lever contacts the ramp on the setting wheel and is moved by rotation of the setting wheel. One end of the plunger is in contact with the lever, the other end being in contact with the backstop. When movement of the setting wheel causes movement of the lever, the plunger is moved in an axial direction thereof, thus causing movement of the backstop. The ramp is positioned on the setting wheel such that the backstop is moved when the setting wheel is turned to an off position.

Abstract: A wireless alarm system utilizes pulsed FM transmissions to increase the effective range of the system while meeting FCC requirements for radiated signal strength. The effective range of the system is increased by shortening the duty cycle and increasing the signal strength during the on-time. This results in a low average RF signal strength, however, an increased transmission distance is achieved.

Abstract: A thermostat is disclosed which includes a Proportional-Integral-Derivative (PID) controller and a means for disabling the PID controller for selected periods. The PID controller is disabled during a temperature recovery period, which can be triggered by the occurrence of one or more of many preselected events. The PID controller is re-enabled when the thermostat setpoint less a void offset temperature is reached. To reduce error in future temperature recovery periods, the void offset temperature is adjusted after a temperature recovery by adding the amount of error to the void offset temperature to create a new void offset temperature for use in a next temperature recovery period.

Abstract: A connector arrangement for an electronic controller includes a plurality of insulation displacement terminals. The connector has a body portion and cover portion. The cover portion includes tabs which will force a wire onto the insulation displacement terminal so that electrical connectors are made. In one embodiment, the connector is connected to a standard phone cable which, in turn, terminates in a modular phone plug.

Abstract: In a valve having a plug and valve seat for controlling the flow of fluid between an inlet port and an outlet port, the plug has radial serrations on its bottom face and has a length for establishing turbulence during the last 1/4 of its stroke as the plug is lifted from the valve seat, the flow through said valve seat being modulated by the turbulence.