Abstract: To obtain a measure of the size of a spot weld nugget, the weld is scanned with an ultrasonic beam of about 20 megahertz frequency. The ultrasonic signal transmitted through the part is analyzed to determine the presence of the part and the presence of a weld. The detected signal is gated to pass a portion of the signal which has been multiply reflected through the weld region to a bandpass filter which passes frequencies that are selectively attenuated by a weld nugget much more than the surface bond or stick zone surrounding the nugget so that the energy content of the filtered signal is used to determine the presence of nugget material at any point during the scan. A chart recorder controlled according to the energy content of the filtered signal produces a characteristic signature for each weld which distinguishes between the extent of the stick zone and the nugget of each weld so that the weld nugget size is readily determined.

Abstract: Spherical parts such as ball bearings are inspected by rolling the parts down sizing rails so that they rotate rapidly with minimal translational motion at a point where they drop through the sizing rails. In a region of rapid rotation the part is inspected by an array of optical systems covering the entire area of the part. Each system focuses a small line of light on the part and in a direction slightly misaligned with the center of the part and the same optics focuses specularly reflected light from the part to a detection region where the light level is measured and a corresponding electrical signal is produced. When the line image scans over a defect, the resulting absorption or scattering of the light causes a rapid decrease in the light received at the measuring location so that a detectable change in the electrical signal occurs.

Abstract: The movement of an article such as a product carried by a conveyor is monitored by providing a patterned target, preferably striped with contrasting lines, to move with the object. A solid state line scan camera views the pattern of the target as it moves relative to the camera and the electronic output of the camera representing the light and dark areas of the target is analyzed by an electronic circuit to determined the movement of the target and therefore of the object being monitored. The resulting electronic signal representing the motion of the object is useful for coordinating the movement of a robot which is operating upon the object during its movement.

Abstract: A measure of engine torque can be obtained by measuring the difference between crankshaft oscillations at the front and rear end of the engine. Angle encoders producing phase outputs attached to the front and rear ends of the crankshaft have their outputs sampled by a phase locked loop to produce instantaneous velocity signals for each unit of crankshaft and a phase comparator connected to both encoder outputs produces a signal proportional to shaft twist. The velocity signals are each differentiated to produce acceleration signals and a calculation circuit scales and combines various signals according to the equation T=A.theta..sub.1 -B.theta..sub.2 +C.theta..sub.1 -E.theta..sub.2 +F(.theta..sub.1 -.theta..sub.2) where T is the engine torque and A, B, C, E and F are constants.

Abstract: A mechanical switch having a plurality of sequentially energized outputs responsive to the displacement of a push button or other linear actuator comprises an arcuate array of fixed contacts on a rigid printed circuit board and a single movable contact comprising a helical spring member with its axis normal to the circuit board and having one end contacting one of the fixed contacts. The spring rate of the spring progressively varies along its length such that when the spring is compressed by an axially applied force the spring sequentially and progressively contacts and bridges the fixed contacts thereby sequentially engaging the fixed contacts.

Abstract: A speedometer cable for a vehicle driven from the vehicle transmission has a speed transducer incorporated in the end fitting which attaches to the transmission housing. The speed transducer comprises, for example, a reed switch driven by a permanent magnet which rotates with the speedometer cable core for opening and closing at a rate dependent on the speed of rotation. The transducer has one terminal grounded through the end fitting to the transmission housing and another lead electrically connected to the reinforcing wire of the speedometer cable. A terminal member with an insulation piercing clip is spaced at a position remote from the end fitting and makes contact with the reinforcing wire to provide an electrical connection between the remote terminal and the reed switch to allow transmission of an electrical speed signal from the reed switch to the remote terminal.

Abstract: A laser beam from a tunable laser is split into two paths containing an etalon and a sample cell respectively. The two paths are chopped at different frequencies. The paths are combined and fed to a monochromator and then detected by a single detector. Lock-in amplifiers tuned to the chopper frequencies and responsive to the detector output produce signals corresponding to the spectra arising from the etalon and the sample gas absorption. A recorder simultaneously displays the two spectra.

Abstract: A low tire pressure sensor for emitting a magnetic signal when the tire pressure reaches a low limit pressure includes a signal device having a magnet movable from a storage position to an actuated position by tire pressure applied to the magnet from an air switch. The air switch includes a bellows charged to a reference pressure and exposed to tire pressure for moving in response to tire pressure changes, and a three-way valve operated by the bellows for venting the signal device to atmospheric pressure when the tire pressure is normal and for closing the vent and applying tire pressure to the signal device to actuate it when the pressure drops below a preset low pressure.

Abstract: Acoustic intensity is measured by a pair of closely spaced microphones aligned in a given direction. One microphone is connected directly to an integrator the output of which is connected to a multiplier while the other microphone is connected directly to the multiplier. The multiplier output is proportional to the imaginary part of the cross-spectrum of the two microphone signals which when time averaged represents the absolute value of the sound intensity in the given direction if the microphone systems are properly phased matched.

Abstract: A height sensor is provided in a vehicle leveling system having an air spring including a pressurized chamber connected between sprung and unsprung vehicle masses. Two radioactive material sources located within the chamber and attached for movement with the unsprung mass emits beta radiation which passes through the wall of the chamber and a pair of beta detectors outside the chamber and mounted on the sprung mass for movement therewith detects the beta radiation to determine the relative spacing of the sprung and unsprung masses.

Abstract: Motor vehicle windows are commonly made of a tempered glass which shatters over its entire area whenever any part of the window is broken. Further, such windows are generally supported at the bottom edge by a channel which extends only part way along the glass leaving an unsupported part of the glass. A switch in the vehicle door is arranged to be held open by the glass and to exert a force against the glass so that if it becomes shattered, the switch force pushes the glass out of the way allowing switch closure. The entire switch is secured to the unsupported edge of the glass or alternatively the switch is mounted on the door panel and only an actuator is secured to the glass.

Abstract: An air core gage having a pair of coils in quadrature to drive a pointer has the first coil energized by a relatively constant reference current while the second coil is energized by a current which varies as a tangent function of the input quantity in order to drive the pointer through an octant of the gage. The current polarity to the second coil is reversed and the current is again varied in the same manner to vary the pointer through a second octant. Then, the reference current is applied to the second coil and the current is varied in the first coil according to the tangent function to drive the pointer through a third octant, and so on for a wide angle pointer drive. When the input quantity is a frequency, the driving circuit is conveniently a digital circuit including a ROM which stores the tangent function of the input quantity and a steering logic circuit which selectively applies the steady state and the variable signals to the gage coils to effect the appropriate pointer movement.

Abstract: A circuit is provided for measuring the effect of temperature on the voltage drop across the semiconductor junction sensor which is located remotely from the measuring circuit and connected thereto by a pair of conductors having substantial lead resistance. The circuit provides a programmed current source which alternately provides to the sensor first and second currents of different magnitudes having a fixed ratio to produce corresponding voltages across the conductors wherein each voltage includes a lead component arising from the lead resistance and the respective current. A sample and hold circuit measures each of the voltages and an amplifier multiplies one of the voltages by the current ratio and the resultant voltages are compared to obtain an output free of any lead component and which varies with the temperature of the sensor.

Abstract: A governor circuit for limiting the maximum speed of an internal combustion engine is effective to minimize overshoot at all ranges of engine acceleration. The system includes a circuit responsive to the engine speed which provides control signals to a solenoid valve which, in turn, controls a vacuum actuator which can override a manual throttle control to move the throttle toward closed position when a governed engine speed is approached. A control circuit provides a signal having a lead component and an integrated signal which comprises a stabilizing component and an integrated speed component. The integrated signal is provided by an integrator having a low sensitivity and high gain at low engine accelerations and a high sensitivity and low gain at engine accelerations above a predetermined switch point. The resulting control signal controls a duty cycle oscillator which actuates the solenoid valve.

Abstract: A circuit for detecting the shorting of a diode in a circuit for rectifying AC current. A current transformer senses the current flowing through a diode. A DC bias current applied to the transformer secondary winding along with the unidirectional pulses normally passed by the diode cause saturation of the transformer core so that the normal current passed by the diode does not induce corresponding pulses in the secondary winding. In the event of diode shorting reverse current pulses will produce corresponding pulses in the secondary winding and those pulses are detected by a relay so that relay actuation occurs upon diode shorting.

Abstract: A variable reluctance pickup for producing electrical pulses in response to the rotation of an adjacent toothed wheel comprises a probe assembly situated tangentially to the path of the wheel teeth. The sensor comprises an elongated core surrounded by a coil and having permanent magnets of opposed polarity at each end of the core. A pole piece extending laterally from one end of the core extends to a point adjacent the path of the teeth of the rotating part. The electrical pulses produced upon part rotation are double the size of pulses produced in the case where only one magnet of equivalent strength to the two magnets is used.

Abstract: A wire bonder for making electrical connections from semiconductor chips to conductors on a lead frame includes a fault sensing system to detect a failure of the ball bond at the chip pad as well as the lead bond. Pad bond failure is detected by providing a wire feed sensor and a logic element for determining whether the wire is being fed when the bonding tip is moved from the chip to the lead. There is no wire feed if the pad bond fails. Lead bond failure is detected by clamping the wire after the lead bond is made and pulling on the wire to either break off the tail at the bond or pull the bond loose from the lead. Then the clamp is released momentarily so that if the tail has not broken free, an extra length of wire will be pulled from the tip. The extra length of wire is sensed by an electronic flame off torch monitor.

Abstract: An air switch responsive to low tire pressure for emitting a pulse of air when a critical low tire pressure is achieved comprises a housing having a chamber ported to the internal tire pressure and a bellows within the chamber filled to a reference pressure. A passageway connecting the chamber to an outlet port is closed by a spring biased poppet valve. A pin on the moving end of the bellows is arranged to extend through the passageway to abut the poppet valve so that when low tire pressure causes bellows expansion, the pin will unseat the poppet valve to allow air pressure to escape from the tire through the outlet port. A second valve surrounding the stem on the bellows engages the chamber end of the passageway to close the same whenever the tire pressure reaches a second critical low pressure to stop the airflow through the outlet port.

Abstract: To prevent buckling and indentation of a panel being spot welded, a welding tip including an electrode of large load bearing and heat conducting surface is used to spread the load and also efficiently cool the workpiece. The large area electrode is a water cooled copper disk of large mass connected to a support arm by a coil spring. An electrical contactor on the support arm releasably engages the electrode to supply welding current thereto when welding pressure is applied to the workpiece by the welding gun. When the pressure is removed, the coil spring separates the electrode from the contactor.

Abstract: A coherent optical correlation system produces an output signal in the form of a beam of light which if focused onto an output plane would produce a spot of light somewhere in that output plane. To detect the position that spot would have in the output plane, the output beam is formed into two parts by a beam splitter and each part is passed through a multiple image diffraction grating arranged mutually at right angles to thereby form a linear array of spots parallel to the x and y axes of a correlation output plane. Each series of output spots illuminates a photodiode in a linear diode array thereby identifying the x and the y coordinates of a correlation image.