Abstract: A semiconductor transducer or actuator is disclosed. The transducer and actuator each include a deflecting member with corrugations producing increased vertical travel which is a linear function of applied force. An accurate and easily controlled method that is insensitive to front-to-back alignment is also disclosed for forming uniform corrugations of precise thickness; independent of the thickness of the deflecting member. The cross-sectional shape of the corregations is not limited by the etching technique, so that any configuration thereof is enabled.

Abstract: A non-dispersive infrared gas analyzer especially adapted for measuring the concentrations of HC, CO and CO.sub.2 in a vehicle exhaust includes a sample chamber for holding a sample gas, a radiation emitter for directing a beam through the chamber and a detector for indicating the amount of radiation absorbed. A plurality of filters, each of which transmit radiation at an absorption band of a gas component to be detected, are alternatingly positioned in the radiation path to produce a time-multiplexed signal having concentration information for all gases. A calibration assembly is provided which includes a plurality of calibration cells selectively positionable in the radiation path in order to provide an internal calibration standard for two-point calibration of each gas channel. The cells contain one or more of the gas components to be measured at concentrations and pressures predetermined to compensate for the difference in optical path length between the calibration cells and the sample chamber.

Abstract: A transducer having a plurality of sensing elements disposed in a single diaphragm wherein each of the sensing elements is spaced from every other of the sensing elements a predetermined distance so as to control interference among the sensing elements. Each of the sensing elements preferably comprises a plurality of piezoresistors each of which are coupled in a Wheatstone bridge configuration. This transducer achieves sensitive, accurate, high spatial resolution measurements of non-uniform pressures.

Abstract: A system for monitoring the continuity and potential rate of leakage of an underground tank hole liner formed of a sheet of electrically insulating polymeric material in which a standard current measurement is made of a circuit comprising a standard electrode in the form of a container of electrically insulating material having a small hole in a side thereof and containing an electrically conductive fluid connected to an injection electrode through a current source, the electrodes being immersed in a conductive fluid in the bottom of the tank hole to provide a calibrated liner leakage value, and such measurement is compared with the current provided by a circuit comprising the injection electrode connected to a ground electrode through the current source.

Abstract: A contrast enhancing, substantially transparent touch panel device comprises a static element, a dynamic element and a microweave screen of a fine mesh of fine dark-colored filaments embedded within a clear adhesive layer and incorporated as an integral part of the dynamic element of the panel. Preferably there is no air gap between the front of the device and the conductive surface of the dynamic element. The device can comprise at least one layer of transparent colored coating for light attentuation, color-selective light filtering, and tint correction.

Abstract: A disc assembly for a bimetallic disc-actuated thermostatic switch is adapted to minimize response time. The switch includes a disc assembly comprising a disc retainer, and a bimetallic disc and a cap on the disc retainer. The disc retainer includes a central hub portion, a plurality of fingers which radiate outwardly from the hub portion, a plurality of disc retainer projections on the fingers adjacent the terminal ends thereof and a plurality of disc support shoulders on the fingers adjacent the disc retainer projections thereon. The fingers have open notches therebetween for reducing the cross sectional area of the material available in the disc retainer for conducting heat from the bimetallic disc to the body portion of a thermostatic switch on which the disc assembly is installed.

Abstract: A fiber optic liquid level sensor having a vertical tube which may be placed in a vessel containing the liquid to be sensed. Disposed for free movement along the exterior of the tube is an annular float equipped with a magnet. A fiber optic cable containing two optical fibers is attached to the top of the tube and the optical fibers extend to a selected point where it is desired to sense the liquid level. There the fibers terminate facing a movable mirror to which a magnet is attached. With a rising liquid level, the mirror is carried upward by the magnetic linkage of the magnet on the float and the magnet to which the mirror is attached. When the mirror reaches the focal point of the optical fibers, the light circuit is closed and an electrical signal derived therefrom may be used to open or close a switch. When the liquid level falls so that the mirror drops below the focal point of the optical fibers, the light circuit will be opened.

Abstract: A gas analyzer for determining the concentration of the oxides of nitrogen in a sample gas is provided. The analyzer is particularly adapted for analyzing the exhaust from an internal combustion engine. In one embodiment, the analyzer comprises a sample chamber and a reference chamber. An arrangement is provided for delivering sample gas containing the lower oxide of nitrogen (NO) to the sample chamber and a quantity of ozone (O.sub.3) for reacting with this oxide of nitrogen and producing a chemiluminescence. After the chemiluminescence is completed, the sample gas is discharged to the reference chamber. A sample photodiode is disposed adjacent to the sample chamber for receiving light emitted from the sample chamber and producing a sample signal representative of the total photoemissivity of the sample gas.

Abstract: A thermally activated snap-action valve includes a valve body having an interior cavity and inlet and outlet passages formed therein and a bimetallic disc, a ball element, and a resilient positioning plate in the cavity. The positioning plate is operative for normally positioning the ball element in inwardly spaced relation to a valve seat at the inner end of the outlet passage, and the bimetallic disc is mounted in the cavity so that the pressures in a fluid passing through the valve are substantially equal on opposite sides of the bimetallic disc. The bimetallic disc is operative with a flexing action in response to a predetermined temperature condition for moving the ball element to a closed position wherein it is received in the valve seat to obstruct the outward flow of fluid through the outlet passage.

Abstract: A wetness detection system for detecting dampness in diapers or other articles of clothing includes a detector/transmitter which is attachable to the diaper or clothing. The detector/transmitter produces and transmits a signal when no urine or other conductive matter is present in the diaper or clothing, and this signal is received by and retransmitted from a retransmitting station which may, for example, be located on the bed of the person wearing the diaper or clothing. The retransmitted signal is ultimately received at a central station for alerting an attendant when a wetness condition is detected. Since signals are transmitted when no urine is present, the absence of signals over some predetermined period of time indicates that wetness is present.

Abstract: Infrared radiation emitted from tissue surface of body cavity is measured by an infrared sensor located within a probe which generates a signal voltage dependent on the difference in temperature between the tissue and the infrared sensor. An additional ambient sensor measures the ambient temperature of the infrared sensor. The signals of the two sensors are added. To calibrate and eliminate errors, the housing of the device is provided with a chamber shaped to receive the probe and containing a target viewed by the infrared sensor. An error signal is thus generated which is added to the signals of the two sensors when they view the body tissue. A disposable, sanitary cover for the probe is made of a truncated polyethylene member of substantially uniform thickness closed by an end window. A filter in the probe suppresses absorption bands of polyethylene to eliminate errors due to minor variations in cover thickness.

Abstract: A temperature sensitive duty cycling control switch is mounted to a forced air ductless gas or oil heater by a special mounting bracket. The bracket attaches to the front of the heater in the path of the heated airflow. The mounting device is basically a tapered conduit or duct which is held at a distance from the heater so that it does not unduly obstruct the airflow and is tapered to concentrate air generated by the heater onto a plate mounted in front of the duct. The duty cycling control switch is then mounted to this plate and responds to the temperature of the plate. This enables the cycling of the heater burner while the fan continues to operate.

Abstract: A system for determining the location of a leak in a pond liner made of electrically insulating material supported by a medium which is electrically conductive consists of a movable nozzle for directing a stream of an electrically conductive liquid against the liner, a ground electrode connected to the electrically conductive supporting medium exterior of the pond and liner, a current source connected between the nozzle and the ground electrode, and a galvanometer located in the electrical circuit comprising the nozzle, current source and ground electrode for monitoring at least one electrical property in the circuit when a change in an electrical property occurs as a result of the stream of electrically conductive liquid completing the circuit by contacting the supporting medium through a hole in the liner.

Abstract: A solid state infrared source is disclosed which is capable of modulation of the intensity of broadband infrared radiation. A silicon semiconductor body is provided with doped regions which have high emissivity for infrared and an intrinsic region which has low emissivity and low absorption for the infrared. The device is heated and maintained at a temperature of about 500.degree.K to effect the infrared radiation from the doped regions. Modulation is effected by controlling the presence of carriers in the intrinsic region, so as to modify the broadband infrared radiation. The modulating carriers may be due to optical modulation or they may be injected electrically. In either case, the heating may be effected by an external device or the doped regions may also provide a heating PIN diode structure which is forward biased in controlled fashion to attain the desired temperature.

Abstract: A bimetallic disc-actuated thermostatic switch comprising a switching assembly including a housing containing fixed and movable contacts and a cap and disc assembly on the switching assembly for moving the contacts between engaged and disengaged positions. The cap and disc assembly includes a bimetallic disc, a support disc for supporting the bimetallic disc on the housing, and a retainer cap for retaining the bimetallic disc on the support disc. The cap has at least one air circulation opening therethrough, and the support disc is formed so that air from the exterior of the cap can pass through the air circulation opening and across the underside of the bimetallic disc to provide increased responsiveness to ambient conditions.

Abstract: A thermally actuated latch for electrical circuits is permanently operative for completing an electrical circuit upon exposure to a predetermined elevated temperature. The latch includes a fixed contact, a movable contact arm which is biased toward the fixed contact, a movable contact on the movable contact arm, and a deformable pellet. The deformable pellet communicates with the movable contact arm through a communicator disc to normally maintain the movable contact in spaced relation with the fixed contact. The pellet is deformable to a disposition of reduced profile upon exposure to a predetermined elevated temperature to allow the movable contact to be resiliently moved into engagement with the fixed contact in order to complete an electrical circuit connected to the latch.

Abstract: A throttle body for an internal-combustion engine having a hollow venturi member positioned within the body. The member has a first portion projecting out of the body at its intake end, and a second portion positioned generally centrally within the body air duct upstream from a throttle plate. The second portion has an exterior surface spaced inward from the body interior sidewall to form an annular venturi passage therebetween. The first and second portions define an enclosed air channel. Circumferentially distributed entry openings in the first portion open exterior of the body duct for entry of air into the channel, and circumferentially distributed exit openings in the second portion communicating with the venturi air passage for the exit of air from the channel. The channel and the entry and exit openings define a sample flow path of air from a location exterior of the duct to a location adjacent to the venturi passage representative of the air mass flow through the duct.

Abstract: A liquid separator for a gas analyzer is provided comprising a sample gas inlet; a sample gas outlet; and a separation chamber in fluid communication with the gas inlet and gas outlet. The separation chamber is provided with a smooth, planar upper wall and a smooth planar lower wall, the upper and lower walls being substantially parallel and having a small uniform clearance therebetween. A motor is provided for rotating the lower wall of the separation chamber about a central axis normal to the surfaces of the upper and lower walls. The gas outlet is disposed on the central axis of the rotating lower wall. The gas inlet is disposed off of the central axis. A vacuum is applied to the sample gas outlet to draw sample gas through the separation chamber. A collection chamber is provided which surrounds the separation chamber for receiving liquids and other debris separated from the sample gas flow by contact with the rotating lower wall and centrifugal acceleration imparted thereto by the lower wall.

Abstract: A gas analyzer for determining the concentration of the oxides of nitrogen in a sample gas is provided. The analyzer is particularly adapted for analyzing the exhaust from an internal combustion engine. The analyzer comprises a sample chamber and a reference chamber. An arrangement is provided for delivering sample gas containing the lower oxide of nitrogen (NO) to the sample chamber and a quantity of ozone (O.sub.3) for reacting with this oxide of nitrogen and producing a chemiluminescence. After the chemiluminescence is completed, the sample gas is discharged to the reference chamber. A sample photodiode is disposed adjacent to the sample chamber for receiving light emitted from the sample chamber and producing a sample signal representative of the total photoemissivity of the sample gas.

Abstract: A cap and bracket assembly for a bimetallic disc actuated thermostatic switch comprises a metallic heat transfer bracket having an aperture therethrough and a metallic cup-shaped cap which is receivable on the housing or body of a thermostatic switch for containing a bimetallic disc. The cap comprises a main portion and a reduced terminal end portion, and the end portion is received in the aperture in the bracket and crimped or swaged to capture the bracket in intimate engagement between the main portion and terminal end portion so that maximum thermal transfer between the cap and the bracket is assured. The method of manufacturing the cap and bracket assembly comprises the steps of assembling the cap with the bracket and crimping or swaging the end portion of the cap to secure the bracket thereto.