Abstract: Generally, in accordance with the various illustrative embodiments disclosed herein, a current sensing probe includes a current-to-voltage conversion circuit that not only presents a desirable impedance into an inductive current sensing element of the current sensing probe, but also remains operationally stable over a wide range of frequencies when measuring a current flowing through a device-under-test. The wide frequency range can extend down to some low frequencies that can prove challenging to conventional current sensing probe circuits.

Abstract: Embodiments of the invention are directed to an equipment data sensor arranged on a powered machine. The equipment data sensor includes a processing device coupled to one or more sensors for obtaining values of at least one parameter associated with running of the powered machine, a memory, and a short range transceiver configured for wireless short range communication arranged to receive short distance communication signals, wherein the processing device is configured to register, in the memory, one or more values of the at least one parameter and an associated operator identifier received over the short range transceiver.

Abstract: A control system for use in safety critical human/machine control interfaces is described, more particularly a joystick type control system and particularly a joystick type control system utilizing magnetic positional sensing. The control system provides a control input device having a movable magnet, a pole-piece frame arrangement positioned about the magnet, at least three magnetic flux sensors being positioned in said pole-piece frame arrangement and a monitoring arrangement for monitoring the output signal of each of said at least three sensors.

Abstract: An angular position sensor and method that relies on a stationary circular array of Hall sensors and a rotatable circular array of magnets arranged about a common axis. A periodic and simultaneous reading of all of the Hall sensor outputs is used to determine angular velocity.

Abstract: A method and a device for measuring the speed of a pulse-activated electric motor are described. According to this method, the motor is fully activated at time intervals to be determined for a defined measuring time by the circuit element provided for timing and, in this time, the frequency of the current ripples, which is proportional to the motor speed, is measured. A current-proportional voltage measuring device is located on the circuit element, on whose load side are located an amplifier, filters, and an evaluation circuit in the form of a comparator for determining the frequency of the current ripples flowing in a measured phase during which the motor is fully activated.

Abstract: The invention provides a structure, method and means for receiving a reference frequency and a variable frequency, differentiating the frequencies, and generating a logic pulse in response to a first frequency leading a second frequency, the frequencies having a small phase difference. In an aspect, the invention maintains a signal when the reference frequency and the variable frequency transition. In another aspect, the invention provides additional timing balance to prevent early generation of the logic pulses. In another aspect, the logic pulses drive a charge pump used in one of a phase-locked loop and a delay-locked loop.

Abstract: A ground pick-up tachometer for detecting a rotational speed of an engine in a vehicle includes a probe arranged for connection to a vehicular ground to detect signals emitted from an ignition system of the engine. A tachometer circuit is operatively connected to the probe to identify the detected signals representing ignition sparks and provide an output representative of the rotational speed of the engine based on the identified signals. The tachometer circuit includes a circuit common reference, separate from the vehicular ground.

Abstract: Absolute engine position sensing is provided by monitoring the temporal relationship of energization of multiple spark plugs sharing a common source of drive energy in a direct ignition application. The spark plugs are connected across the source with opposing electrical polarity, and the relative time of discharge across the plugs compared by sensing the time and polarity of high speed transient activity in proximity to the source.

Abstract: An electronic meter for testing engine parameters includes a slide switch and related circuitry for detecting, scaling and displaying the correct value of engine speed for both a conventional four stroke engine and a DIS four stroke engine, as well as for a two stroke engine. The electronic meter has a pickup which is adapted to be placed around a lead from a spark plug in the engine. The electronic meter is adapted to be triggered when a current spike in the spark plug lead is above a selected threshold value. When the electronic meter is triggered, a voltage pulse is stored in an integrating circuit in the meter. The electronic meter scales the voltage across the integrating circuit, measures the scaled voltage, and displays the value on the meter. The slide switch and associated circuitry for the electronic meter are adapted to vary the threshold level for the trigger, as well as appropirately reduce the output voltage of the integrating circuit, depending on the type of engine being tested.

Abstract: A rotational speed detector for an internal combustion engine comprises a waveform processor for eliminating pulses generated within a predetermined period of time after a certain pulse appears and a measuring circuit for measuring a rotational speed based on outputs from the waveform processor. The waveform processor of the rotational speed detector thus eliminates the effects of such an unexpected pulse generated, for example, by the vibration of the ignition coil for the engine. Consequently, the measuring means detects the rotational speed accurately without measuring the unexpected pulse.

Abstract: An improved input circuit for an electronic vehicle speed control unit is disclosed. An ignition current sensor coil is adapted to have a voltage differential signal induced therein each time an ignition pulse is generated by the vehicle engine. Electrical noise signals generated by the vehicle engine appear as common mode signals across the ignition current sensor coil. The ignition current sensor coil is connected at each end to a capacitor, both of which are connected to ground potential. The ends of the ignition current sensor coil are further connected to the inputs of a differential amplifier. The capacitors appear in a series loop with the ignition current sensor coil for the differential voltage signals and, consequently, provide tuning for inductance. However, the capacitors appear in parallel with one another to ground potential with respect to the common mode noise signals, thereby providing high frequency noise rejection for the input circuit.

Abstract: An improved automotive ignition analyzer is provided for use with electronic ignition systems. A quadrature field magnetic pickup is utilized to detect signals in the secondary circuit of the ignition system. An adaptor including a voltage clamp is connected to the tachometer lead of the electronic ignition system so that a power balance test may be performed in the conventional manner without harming the electronic ignition system.

Abstract: A method and apparatus for determining the rotational speed of an engine, using electrical pulses produced with revolving parts of the engine, including the use of a number of series of transducers or pickups producing numbers of asynchronous pulses, different for each series during each revolution of the engine, the transducers corresponding to as many series of detection elements comprising teeth and/or bosses spaced on the periphery of corresponding revolving parts of the engine, such that if n is the number of detection elements of a largest series giving the highest pulse frequency for a corresponding transducer due to engine revolution, and q is the total number of transducers associated with another series of detection elements, then the angular location of said another series of detection elements is obtained to the nearest 360.degree./qn.

Abstract: A system for indicating engine speed without physically contacting the engine, including a tachometer comprising an inductive loop which may be buried in the ground and connected to an electrical amplifying system which picks up very low frequency radio frequency (RF) pulses from the ignition system of an automobile or other vehicle whose engine is located above the loop. The tachometer includes controls for selecting the number of engine cylinders corresponding to the vehicle being tested and a meter readout providing a visible or other suitable indication of the vehicle's engine speed. Undesirable background noises are substantially eliminated by the pickup loop design and its orientation, input signal filtering, power line filtering, base line signal rejection and automatic gain control.