Abstract: An internal combustion engine with a throttle valve, fuel supply and dilution (EGR) control includes apparatus effective to detect a throttle tipout condition comprising a rate of throttle closing exceeding a predetermined reference rate and decrease the dilution from the scheduled value to its minimum value during the existence of the throttle tipout condition and further apparatus effective to detect the end of the throttle tipout condition and return the dilution to its scheduled value at a controlled rate. Thus, a sudden unscheduled increase in dilution caused by a throttle tipout associated increase in intake manifold vacuum is reduced and driveability improved.

Abstract: An LLP ignition timing control for an internal combustion engine periodically senses LPP in an engine combustion chamber and generates an average LPP value. A DLPP value indicating a desired LPP is generated; and ignition timing is periodically adjusted. The apparatus advances ignition timing if the average LPP value is retarded with respect to the DLPP value. The ignition timing is maintained in the same direction as the previous adjustment if the average LPP is advanced and becoming less advanced with respect to the DLPP value, but is reversed to the opposite direction from that of the previous adjustment if the average LPP is advanced and becoming more advanced with respect to the DLPP value. The amount of adjustment is proportional to the product of the difference between the average LPP value and DLPP value and the rate of change in the average LPP value. Thus, MBT is maintained in spite of the foldover effect in the LPP vs.

Abstract: A peak combustion pressure signal processing circuit for an internal combustion engine having a plurality of combustion chambers with combustion pressure sensors includes an operational amplifier for each sensor with an output connected through a diode to a common junction. Each operational amplifier has a feedback circuit from the common junction to its input effective to cause its output voltage to decrease so as to reverse bias its output diode when the voltage on the common junction exceeds the voltage derived from the associated sensor, whereby only the diode passing the maximum combustion pressure signal is forward biased. A logic circuit having inputs from the common junction and the outputs of at least all but one of the operational amplifiers determines which diode is forward biased and assumes a uniquely identifiable output state.

Abstract: A power window control circuit for a motor vehicle includes a FET and SCR in series across the power supply with their junction connected to one side of a motor armature, the other side of the motor armature being switchable between power supply terminals. To provide reverse battery protection, no anti-parallel diode is provided around the SCR. The activation circuit for the FET includes a capacitor bootstrap circuit controlled by a switching transistor and a zener diode from the drain to the gate. When conduction from the switch through the motor and SCR is stopped, the inductive energy from the armature windings dissipates through the internal anti-parallel diode of the FET. When opposite conduction from the FET through the motor and switch is stopped, the inductive energy causes the voltage across the FET to rise to the zener voltage and turn on the FET sufficiently to dissipate it.

Abstract: Slot antenna apparatus for a motor vehicle roof made of an electrically conducting material with a central non-conducting portion comprises a horizontal sheet of electrically conducting material attached to the roof, the horizontal sheet including a looped slot adjacent the central non-conducting portion which divides the sheet into inner and outer portions, the slot having a total loop length of substantially one wavelength in the commercial FM broadcasting band. The horizontal sheet material has a comparatively high sheet resistance of 1 to 2 ohms per square to produce a maximum VSWR of 5 and preferably below 3. The material may be comprise a coating of nickel in an acrylic binder on the underside of an SMC roof panel.

Abstract: A combustion control for an internal combustion engine adjusts ignition timing and A/F ratio to even the torque pulses of the individual cylinders as well as adjust LPP toward a desired value (DLPP). The crank angle (LPP) and magnitude (MPP) of peak combustion pressure is sensed for each cylinder and the average MPP for all cylinders (AMPP) is derived. Ignition timing is trimmed, within a first limit, in response to LPP to attempt to maintain DLPP. MPP is compared with AMPP and, if it is too low, ignition timing is trimmed in the advance direction to a second limit, which is preferably larger than the first. Only if the MPP trim of ignition timing is at maximum advance, or if MPP is too high, is A/F ratio adjusted, with MPP trim of ignition reset to zero. Thus, fuel consumption is minimized as the cylinder torques are balanced.

Abstract: A charge dilution control for an internal combustion engine subjects a combustion pressure signal to multiple switched capacitor bandpass filters with frequencies controlled in phase lock loop from engine speed to generate harmonic wave signals at frequencies which are constant multiples of the varying firing frequency. The amplitude ratio between the peaks of two harmonics, with one preferably the fundamental firing frequency, is used to control charge dilution apparatus such as EGR or variable valve lift to maintain a predetermined ratio. The harmonic compared to the fundamental may be a higher harmonic or a subharmonic. Ignition timing for the engine may be controlled to maintain a phase difference of zero between two of the higher harmonics such as the second and fourth.

Abstract: An ignition timing control for an internal combustion engine subjects a combustion pressure signal to multiple switched capacitor bandpass filters with frequencies controlled in phase lock loop from engine speed to generate harmonic wave signals at frequencies which are constant multiples of the varying firing frequency. The phase difference between the peaks of two harmonics such as the second and fourth is used to control ignition timing to a phase difference of zero, in some cases with ignition pulses referenced to the detected peak of the first harmonic (fundamental) rather than a detected crankshaft position. The ratio of peak amplitudes between two harmonics such as the first and fourth is used to control dilution by EGR or variable valve lift to a predetermined ratio. The ratio of the peak amplitude of subharmonics to the fundamental may be used as a roughness or driveability sensor.

Abstract: A mixer is disclosed for use in a dual conversion AM-FM radio receiver in which AM and FM broadcast RF signals from a first IF amplifier are converted by the mixer from a first intermediate frequency to a second intermediate frequency for amplification in a second IF amplifier. A double balanced mixer circuit receives a signal at the first intermediate frequency and a local oscillator signal to generate signals at the second intermediate frequency on its two complementary outputs. One of the outputs is connected to the second IF stage through a narrow bandpass ceramic filter at the second intermediate frequency and a transistor switch. The other output is connected to the second IF stage through another transistor switch. The transistor switches are responsive to an external signal to alternatively connect the output through the ceramic filter for AM signals and the other output for FM signals.

Abstract: A power latch circuit uses first and second bipolar transistors responsive to an actuate voltage to latch into a conductive state with power supplied to a computer and a third bipolar transistor powered by the latch circuit and responsive to a deactivate voltage from the computer to place the first and second transistors in a deactivated state to remove power from the computer and itself. It further uses an FET in parallel with the third bipolar transistor and activated directly from the DC power supply when the second transistor is deactivated to latch the first and second transistors in the deactivated state in spite of voltage fluctuations on the deactivate line which might otherwise cause the latch circuit to reactivate. As an FET, it uses little current through its gate compared to alternative bipolar devices while the latch circuit is deactivated.

Abstract: A method is disclosed for laser welding two sheets of metal, the metal being of the type having associated gases tending to be trapped and expand in the weld zone during welding due to heat from the laser. These expanded gases tend to separate the upper and lower portions of the weld zone and/or expand through the weld zone toward the laser beam to create porosity in the final weld. Such metal may be coated, such as galvanized steel, in which case the zinc vaporizes into a gas in the weld zone between the adjacent sheets, or it may be poorly fitting sheets, in which case air is trapped in surface irregularities between the sheets. In either case, the method adds to the standard laser beam a surrounding stream of pressurized shield gas effective to create a pressure at the surface of the weld zone sufficient to force the molten metal of the two sheets together and force the expanded associated gases out of the weld zone in a direction away from the laser beam, whereby a non-porous weld may be created.

Abstract: A power window control for a motor vehicle provides express or one-touch movement in response to short activations of a control element and traditional power window movement during activation of the control element for longer periods. The control provides for automatic window closing with activation of a power door lock element, as long as the ignition is off unless the ignition key is in the ignition switch and the driver's door is open. This allows single touch vehicle locking but helps prevents the operator from locking himself out of the vehicle with the key still inside. Window movement, once initiated in the open or close direction, is stopped in response to motor stall when the open or closed limit is reached.

Abstract: An AM-FM-cellular telephone multiband antenna adapted for mounting on a motor vehicle fender includes, connected collinearly in order from the bottom, a first mast section having a length of one quarter wavelength at a first frequency near 835 MHz in the cellular telephone band, a phasing coil having an electrical length of one half wavelength at the first frequency, a second mast section having a length of one half wavelength at the first frequency, a trap coil resonant at the first frequency and a third mast section. The trap coil isolates the second and third mast sections at the first frequency so that the phasing coil and second mast section adding gain to the first mass section in cellular telephone reception at frequencies near the first frequency. However, the trap coil connects the second and third mast sections to provide a tuned quarter wavelength antenna at a second frequency in the FM radio band while providing reception at frequencies in the AM radio band.

Abstract: A pulse width modulated DC motor operating system is disclosed which reduces the communication back to the power supply of transient spikes caused by the switching characteristics of the freewheeling diode. The switched current path comprises, in series, a DC power supply, a low pass filter including charge storage means, a DC motor armature, a FET and a resistor. A freewheeling diode is connected across the motor armature. PWM signal generating apparatus switches the FET to control average motor armature current. A capacitor is connected across the FET and diode with minimal lead length to reduce stray inductance.

Abstract: A peak combustion pressure timing (LPP) sensor is disclosed for a spark ignited internal combustion engine comprising a probe fixed with respect to the stationary portion of the engine and disposed adjacent a detectable member moving longitudinally with the valve stem of a combustion chamber intake poppet valve as the valve closing portion of the poppet valve is distorted by combustion pressure. The probe may be a proximity probe which senses the longitudinal movement of the member and thus the valve stem and generates an electric output signal thereof. Further apparatus senses the signal peak value, which signifies peak combustion pressure, and references the peak value with the crankshaft rotational position of the engine so as to indicate the timing thereof.

Abstract: A serial pulse frequency converter is disclosed of the type which counts high frequency clock pulses between input pulses, multiplies each successive count by first and second proportionally constants and downcounts the products by high frequency clock pulses to produce output pulses at a new, proportional frequency. A first serial register is used to both count the high frequency pulses between input pulses and hold the count during the multiplication process. It is loaded at the end of multiplication with the a number representing the "lost counts" as it is switched to its counting mode. A second serial register accumulates the sum of partial products of the count and the proportionality constants. The gain circuit serially provides a first proportionality constant and then a second, but may selectively substitute a binary number representing a constant unity for the second.

Abstract: A control for an electrically powered, motor vehicle windshield wiper system with independent drive motors for the wiper blades which produces an opposing wiper pattern with overlapping park and which is simple and inexpensive to manufacture by providing a unique switching system which coordinates the blades to prevent interference therebetween and converts simply and effectively, when the system is turned off, to a blade parking control which allows continuation of normal blade movement into a predetermined park position. The control provides switch control for the motor of each wiper blade in response to certain predetermined positions of the other blade, including, in particular, a position adjacent but outside the wipe pattern of the other blade wherein the controlled blade may be stopped if necessary to avoid interference.

Abstract: A control for separately driven, potentially interfering wiper blades includes position sensors for each wiper blade and a memory which stores, for each pattern, numbers representing inner and outer wipe positions with acceleration, constant velocity and deceleration regions therebetween and a command velocity for the constant velocity regions. The memory further stores numbers defining a zone of potential blade interference and, for each position of each blade within this zone, a non-interference zone for the other blade. The control further includes closed loop velocity control apparatus responsive to the signals from the position sensors and the command velocity to maintain the command velocity in the constant velocity region, accelerate to the command velocity in the acceleration region and decelerate from the command velocity in the deceleration region.

Abstract: An adaptive knock control for a spark ignited, internal combustion engine is disclosed in which a signal indicating sensed knock induced and other bursts of engine vibrations is passed through a bandpass filter effective to tune the apparatus to a characteristic knock frequency which is variable with engine speed. The filter tuned frequency may be varied directly with engine speed to follow the characteristic knock frequency. Additionally or alternatively, it may be varied, at a particular engine speed, in a first direction away from the knock frequency avoid a strong engine noise component in the opposite direction from the knock frequency.

Abstract: An adaptive knock control for a spark ignited, internal combustion engine is disclosed in which a signal representing sensed knock induced and other bursts of engine vibrations is demodulated to generate pulses corresponding to the envelopes of such knock induced and other burst of engine vibrations. Discrimination apparatus responsive to pulses duration compares each to a discrimination reference and selectively discriminates in favor of those having a longer duration characteristic of knock induced bursts. The discrimination apparatus is responsive to engine speed to vary the discrimination reference therewith in the direction of shorter time durations with increased engine speed and longer time durations with slower engine speed. If the discrimination apparatus is a low pass filter, its corner frequency is varied directly with engine speed. If the discrimination apparatus is an ignore timer, the ignore time is varied inversely with engine speed.