Abstract: A reflecting standard for an optical apparatus comprises a semitransparent crystal or glass which reflects from its front surface a predetermined proportion of the incident light dependent upon the index of refraction at the wavelength of the incident light. The rear surface of the reflector is disposed at an angle to the front surface and is provided with an antireflecting coating to minimize reflection therefrom.

Abstract: To measure the percentage of soot in a diesel engine crankcase oil without any significant influence by oil additives or contaminants which build up in the oil during usage. The relative permittivity of the oil is measured in the microwave region of 8-12 GHz (X band). For soot content up to about five percent, the relative permittivity of the oil is a substantially linear function of the soot content.

Abstract: A low tire pressure transducer coupled to a tire rim includes a diaphragm subject to tire pressure on one side and to a mechanical spring force on the other side. A magnet within the transducer is coupled with a shunt which minimizes the external magnetic field when tire pressure is at its proper value. However, movement of the diaphragm occasioned by low tire pressure also moves the shunt so that the external magnetic field increases substantially. Movement of the shunt also opens a valve which relieves any air pressure buildup in the transducer on the spring side of the diaphragm thereby avoiding premature actuation of the transducer due to air leakage into the transducer. A retaining ring holds the transducer to the rim and contains vents for allowing the exhaust of air from the transducer.

Abstract: A fan in a duct driven by a permanent magnet D.C. motor powered by a constant voltage source varies in speed according to the airflow through the duct. The current drawn by the motor is a direct function of the air speed and the density. The motor current is measured to provide a measure of mass airflow.

Abstract: An actuator is provided to selectively turn a diesel engine governor shutoff shaft to fuel "off" or fuel "on" position in response to keyswitch operation. An electric motor coupled through a gear train to a shutoff lever turns the lever to "on" or "off" position. A relay circuit controls the motor operation in response to keyswitch position and shutoff lever position. A feedback element moving with the shutoff lever mechanically interrupts the relay circuit by overriding the relay contact state to turn off the motor whenever the shutoff lever reaches an "on" or "off" position.

Abstract: A line of laser light is produced having a uniform intensity over an area of ten centimeters by one centimeter and having an energy density of several J/cm.sup.2. A grating forms from a laser beam several divergent beams of nearly equal intensity and a converging lens collimates the beams into slightly overlapping paths to produce a uniform line of light in one plane. A laser amplifier in a flat plate configuration in that plane includes a nested series of laser rods of triangular cross-section which are pumped by a plurality of flashlamps to amplify the line of light and produce an intense uniform line of laser light.

Abstract: A compliant O-ring seats on the abdomen surrounding the stoma and contacting the stoma. A pouch sealing ring having an annular flange fits over the O-ring to form a sealer therewith. A waste collection pouch is secured to this sealing ring and has an opening aligned with the washer and the O-ring and a belt attached to the sealing ring secures the appliance to the body of the user.

Abstract: A capacitive probe for sensing the presence of water in a fuel tank increases in capacitance when water is present. A threshold detector circuit includes the capacitive probe and a reference capacitor and an oscillator for periodically charging them to the same voltage and a comparator for comparing the capacitor voltages during discharge to determine when the probe capacitance exceeds the reference capacitance. The comparator controls a lamp driver which is connected to ground and which is also connected by a single conductor to a remote indicating lamp in series with a power supply. The single conductor carries the lamp energizing current as controlled by the lamp driver and also supplies the operating voltage to the detection circuit.

Abstract: To provide an electrical vehicle speed signal as well as a traditional speedometer cable drive, a sleeve member for mounting in a port of the transmission housing and a driven gear on a shaft journaled in the sleeve member are modified by providing a magnet on the gear for rotation therewith, an annular sensing coil around the sleeve member and a U-shaped polepiece linked through the coil and extending into magnetic coupling relationship with the magnet so that electrical pulses are induced in the coil upon gear rotation.

Abstract: To provide a visual indication of low tire pressure, a valve stem comprises a base for mounting to a tire rim, an outer nipple portion containing a tire stem valve, and an intermediate convoluted portion connecting the base and the nipple. An inner extension of the nipple passes through the base portion and has its inner end secured to a spring which is compressed between the extension and the base portion to urge the nipple toward the tire rim against the force of the tire pressure so that the spacing of the nipple from the rim is a measure of tire pressure. A transparent cylinder surrounding the valve stem and secured to the base portion contains a window for viewing an indicia mark on the nipple, the indicia being placed to provide an indication of low tire pressure when it is visible through the window.

Abstract: To securely mount at least two panels such as printed circuit boards in spaced parallel relation, a molded plastic spacer device is provided for coupling the panels to a mounting bracket and firmly holding the panels without stress.

Abstract: A single optical sensor coupled to an oil return line in an internal combustion engine is coupled to a control circuit for determining during a first time interval when the engine is started whether the crankcase oil level is sufficient and during a second time interval after the engine is running whether the oil needs to be changed.

Abstract: A thumbwheel actuated variable resistor device has a housing comprising a substrate carrying a resistor pattern and a cover with electrical terminals embedded therein and a thumbwheel in the space between the substrate and cover. The thumbwheel carries a pair of conductors which extend from opposite sides thereof to selectively engage portions of the resistor circuit and the terminals so that the resistance between the terminals depend on the thumbwheel position.

Abstract: A pressure sensor element comprising a silicon chip having a diaphragm formed therein with piezoresistive strain responsive resistors is mounted in a housing of molded polyester material having a much different temperature coefficient of expansion than the chip. The chip is protected from thermally induced and other stresses by a mounting arrangement comprising a glass base secured to the housing by a soft adhesive which largely prevents stress being transmitted from the housing to the base, wherein the base has a short pedestal on which a glass die is mounted which, in turn, supports the silicon chip. The short pedestal adds localized rigidity to the base so that any stresses in the base are taken up outside the region of the pedestal. One face of the glass die is bonded to the base by a relatively soft epoxy to further inhibit stress transmission and the silicon chip is securedly bonded to the opposite face of the die.

Abstract: To provide a nonvolatile alpha-numeric display, display segments comprising small electrets are arranged in a supporting panel in a desired format such as a conventional seven-segment display. Each electret segment is pivotably mounted in a window in the support panel and has opposite faces of contrasting colors so that the rotational position of the electret segment determines its appearance. Electrodes on opposite sides of each window are connected to a control circuit for applying an electrostatic field across the window effective to cause rotation of the segment from one state to another. Various alpha-numeric characters can be formed by selectively rotating the segments. A switch function on each segment allows the status of each segment to be electrically sensed to thereby provide a nonvolatile memory.

Abstract: An apparatus for providing a service reminder when a vehicle has accumulated a predetermined mileage comprises a potentiometer operated by the highest order number wheel of the vehicle odometer to provide an output voltage which changes incrementally with each indexing motion of that number wheel. An electrical detector responsive to the potentiometer output energizes a signal lamp when the output reaches a voltage in a predetermined range representing a desired service interval. An electrical connector in circuit with the potentiometer can be disconnected to change the potentiometer voltage to a value outside the predetermined range to allow the service reminder circuit to turn off the indicator lamp when the indicated service has been performed. The apparatus is adapted to operate in conjunction with an electronic engine control module which can be programmed to detect the predetermined value of the potentiometer output and to operate a signal lamp.

Abstract: Both junctions of a thin film thermocouple are formed on one side of a glass substrate. That side of the substrate is exposed to the diesel engine oil the soot content of which is to be measured. A light source on the other side of the substrate has its radiation directed through the substrate to a location at one of the junctions so that the light is absorbed by the oil adjacent that junction to a degree determined by its soot content. The temperature of the oil and the adjacent junction are increased by an amount dependent on the soot concentration and the thermocouple output is therefore a measure of the soot concentration in the engine oil.

Abstract: A steering column switch assembly includes a carrier housing mounted on a steering column adjacent a steering wheel thereon. A plurality of switches, each in a housing, is detachably mounted in the carrier housing between a respective one of a plurality of pairs of parallel carrier faces on the carrier housing and extending parallel to the axis of the steering column. Resilient means on each switch housing engage stop surfaces on the respective pair of carrier surfaces to retain said switch housing in said carrier housing.

Abstract: Magnetic and dielectric properties of a sample are determined by measuring the microwave absorption of the sample. A cavity containing the sample material is coupled to a microwave source and the radiation propagated to the cavity is modulated at a reference frequency. A microphone coupled to the cavity senses the pressure fluctuations resulting from the thermal changes generated in the sample by the absorption of the modulated microwaves and the microphone signal is analyzed at the reference frequency to provide an electrical output which is a measure of the microwave absorption by the sample material. Both dielectric and magnetic properties of the sample can be measured.

Abstract: Predominately hydraulic controls with an optional electrical feedback loop for a compression molding press is provided for a press having the main force provided by four hydraulic cylinders one at each corner of the ram and a fifth cylinder at its center. A hydromechanical servo valve at each corner of the press each in conjunction with a position gauge rod controls the adjacent cylinder to keep the ram parallel with the bed and an averaging valve applies the average pressure of the corner cylinders to the central cylinder. A servo controlled position motor synchronously moves each of the hydromechanical valves with respect to the ram to affect position and velocity control of the ram. A force comparator samples the average cylinder pressure to establish a maximum pressure and to override the position control when that maximum pressure is approached. The electrical control senses the position of the servo controller to compare press position to a preset program and to control the servo accordingly.