Abstract: A reversible ratcheting electric power tool has a reversible DC electric motor having an output coupled to drive a drive shaft through a reversible ratchet assembly. The tool housing has a reversing mechanism which includes a manually operable reversing cap rotatable about the axis of the drive shaft for controlling the ratcheting direction of the ratchet assembly, the cap having a pair of projections which respectively engage the actuator buttons of two direction control microswitches coupled through an on-off switch to a battery. When the ratchet assembly is in a neutral or non-ratcheting condition, both microswitches are in a normal deactuated condition connecting both of the motor terminals to the battery negative terminal.

Abstract: A ratcheting electronic torque wrench has an input beam in the form of a hollow housing with a handle end and a work end, a ratchet head disposed within the work end of the housing and rotatable relative thereto and a reaction beam disposed within the housing and having one end fixed to the ratchet head for pivoting therewith about the axis thereof and an input end resiliently urged to a neutral position relative to the housing by two bias springs respectively engaging opposite sides of the reaction beam. A Hall-effect sensor carried by the input end of the reaction beam is disposed between two permanent magnets and is powered by a battery for producing an output indicative of reaction beam movement, which is proportional to applied torque. A display circuit can display the applied torque or a predetermined torque level set by a preset circuit. An alarm signal is generated when the applied torque reaches the predetermined level.

Abstract: An evaporative emission tester is used to evaluate the integrity of a vehicle's evaporative emission control system, including determining the system's purge capability. The emission tester performs a purge flow test to determine whether fuel vapor stored in the vehicle's evaporative canister and present in the fuel tank is being drawn into the engine for combustion at a minimum amount. The emission tester also performs a pressure test of the vehicle's evaporative canister purge system, which includes the fuel tank and lines. The emission tester can function as a stand-alone unit or as an integrated product with a host computer.

Abstract: A battery impedance monitor includes a driver section having an oscillator which produces a pulsating loading signal which controls periodic loading of the battery to produce at its output terminals a pulsating voltage component having a peak-to-peak amplitude superimposed on the DC output voltage of the battery. This pulsating voltage component is detected in a measuring section, which applies the battery output through a voltage divider to a peak detector which outputs an indicating voltage level proportional to the peak-to-peak amplitude of the pulsating output signal, this indicating level being held on a storage capacitor. The voltage divider includes a Zener diode which shifts the DC level of the battery output without affecting the amplitude of the pulsating component.

Abstract: An evaporative emission tester is used to evaluate the integrity of a vehicle's evaporative emission control system, including determining the system's purge capability. The emission tester performs a purge flow test to determine whether fuel vapor stored in the vehicle's evaporative canister and present in the fuel tank is being drawn into the engine for combustion at a minimum amount. The emission tester also performs a pressure test of the vehicle's evaporative canister purge system, which includes the fuel tank and lines. The emission tester can function as a stand-alone unit or as an integrated product with a host computer.

Abstract: A diesel timing light includes a flash circuit for flashing a xenon lamp in response to ignition events sensed by a knock sensor. A trigger circuit enables the flash circuit only in the presence of an enable signal, which is generated by a sensing circuit immediately before the ignition of the no. 1 cylinder. The sensing circuit includes a visible laser source which illuminates a patch of reflective tape on the engine flywheel just ahead of a timing mark corresponding to engine top dead center. The tape reflects the visible laser light to a sensor which generates the enable signal. The trigger disables the flash circuit immediately after the flash triggered by the first ignition event after the enable signal. LED indicators indicate when the photosensor is detecting the reflected beam and when the knock sensor is detecting ignition events.

Abstract: A torque-angle wrench is provided with a handle for applying torque, such as to a fastener or bolt, through a tightening angle, at a rotational angular velocity. A piezoelectric gyroscopic sensor device including circuitry for vibrating an oscillating body is coupled to the wrench. As the wrench is rotated through the tightening angle, its rotational angular velocity causes the vibrating body to alter its direction of vibration. The new vibrating pattern is sensed and converted, by appropriate sensing circuitry, into an electrical signal proportional in intensity to the rotational angular velocity of the wrench. The electrical signal can be electronically processed by appropriate conversion and display circuitry to provide a visual indication of the tightening angle. Such conversion and display circuitry can be integral with the wrench or as part of an adaptably coupled meter non-integrally connected to the sensor device.

Abstract: A battery and charging system tester includes an automatically-operated carbon pile for loading the battery, the pile having a shaft therethrough rotated by a stepper motor, and a compression nut threadedly engaged with the shaft for movement into and out of engagement with the carbon pile in response to rotation of the shaft for varying the compression of the pile and, thereby, the impedance thereof. Probes are provided for sensing battery load current and output voltage, and the output current of an alternator charging unit. A feedback control circuit including a microprocessor operating under stored program control converts the analog probe outputs to digital signals and compares the battery output voltage and load current to selectively variable references for controlling the stepper motor to vary the battery load so as to regulate either the battery load current or the battery output voltage to a predetermined reference value, depending upon the test being performed.

Abstract: A battery and charging system tester includes an automatically-operated carbon pile for loading the battery, the pile having a shaft therethrough rotated by a stepper motor, and a compression nut threadedly engaged with the shaft for movement into and out of engagement with the carbon pile in response to rotation of the shaft for varying the compression of the pile and, thereby, the impedance thereof. Probes are provided for sensing battery load current and output voltage, and the output current of an alternator charging unit. A feedback control circuit including a microprocessor operating under stored program control converts the analog probe outputs to digital signals and compares the battery output voltage and load current to selectively variable references for controlling the stepper motor to vary the battery load so as to regulate either the battery load current or the battery output voltage to a predetermined reference value, depending upon the test being performed.

Abstract: A linearly moving external part on a multi-cylinder internal combustion engine is contacted with a hand-held rotary encoder, contact tachometer having a hollow handle in which processing circuitry is disposed for converting the rotary encoder output to a waveform signal. This signal, along with a signal responsive to the firing of the number one cylinder, are applied to an engine analyzer processor for display of a single engine cycle of the waveform signal on the CRT oscilloscope of the engine analyzer. The variations in amplitude of the waveform signal correspond to speed variations of the moving part over an engine cycle to give an indication of the relative power contributions of the individual cylinders.

Abstract: An inductive pickup assembly senses the electromagnetic fields of plural ignition elements of an automotive engine, access to which elements is prevented by associated engine housing structure. The pickup assembly includes a frame having a flat platform on which multiple sensors are mounted, each sensor comprising an electromagnetic pickup coil with a magnetizable metal core integral with a magnetizable metal shield plate which covers one end of the coil. The frame has a support member with depending feet having apertures which mate with fasteners on the housing structure to serve as a template for accurately locating the pickup assembly on the housing structure.

Abstract: A torque wrench having a torque plug integral with the back side of the torque wrench handle and with strain sensing elements mounted on the torque plug and connected to signal processing circuits supported by the handle which control a digital display unit mounted on the handle. The processing circuits include a peak hold detector enabling display of the peak torque value during a torquing operation, and a peak hold response delay insuring capture of the peak torque value.

Abstract: The adapter includes a luminosity probe for replacing the glow plug associated with the selected cylinder in a diesel engine, a timer circuit responsive to inception of each electrical signal generated by the luminosity probe to produce a timer signal. The timer signal is differentiated to produce a spike. A pickup loop receives the spike and produces an inductive signal for application to the clip of a spark-ignited-engine timing meter.

Abstract: An oscillator provides a series of pulses to the first of a plurality of cascaded counters. The BCD outputs of each counter provide a particular digit in the number of pulses counted during selected intervals. At least two AND means are coupled to respective sets of the counter outputs to provide speed signals when the corresponding numbers of pulses have been counted. A selected one of such signals resets the counters and also provides an inductive output for the magnetic probe of a timing meter. Additional AND means are respectively coupled to different sets of the counter outputs and provide timing signals when their respective numbers of pulses have been counted. A selected one of the timing signals energizes an LED which produces a light flash for the luminosity probe of the timing meter.

Abstract: The adapter includes a housing containing a rectifier for supplying flash voltages to an LED. The rectifier rectifies inductive signals derived from an inductive pickup. The adapter can be used to enable a spark-ignited engine calibrator to calibrate a diesel-engine-timing meter by converting the inductive electrical signals from the calibrator to light signals for the diesel timing meter. The adapter also can be used to enable a diesel-engine-timing meter and analyze and time a spark-ignited engine by converting the inductive pulses derived from a spark plug wire into light impulses for the diesel-engine-timing meter.

Abstract: The probe includes a tubular housing having a first portion and a second portion. The first portion is adapted to be mounted in place of the glow plug of a selected engine cylinder. A light pipe within the first portion directs light from the combustion zone to a phototransistor within the second portion. The front of the first portion has a reduced size aperture defined by an internal shoulder against which the front of the light pipe is seated. The rear of the first portion carries resilient sealing means which is deformed when the second portion is telescoped thereon so as to provide a detachable, frictional, light-tight thermally insulated connection therebetween. A phototransistor is mounted within the second portion to convert light passing through the light pipe into electrical signals. A cable carries these electrical signals to processing equipment. A base resistor is located in the second portion between the base of the phototransistor and the cable.

Abstract: A first signal at a first frequency which is a selected harmonic of the resonant frequency of a bolt in a first loaded condition is determined. Then there is determined a second signal at a second frequency being the same harmonic of the resonant frequency of the bolt in a second loaded condition. Both frequencies are multiplied by a factor M. The up input of a counter receives one of the signals for a predetermined duration, and the down input receives the other signal for the same duration. The number of pulses remaining in the counter is representative of the difference in load between the first and second loaded conditions.

Abstract: The apparatus comprises a luminosity probe to provide an electrical signal in response to the combustion event in a diesel engine and also comprises a probe to provide another electrical signal indicative of top dead center. Both electrical signals are processed and applied to a circuit which generates an output pulse having a duration corresponding to the time between the start of the electrical signals. A meter displays the angle represented by the duration of such pulse. Circuitry is provided to compensate for offset.