Showing papers on "Impulse generator published in 1978"

Cable fault location

Abstract: A fault in a cable comprising at least two conductors is located by applying a single voltage impulse between two conductors of the cable, passing the resultant current wave form through a primary winding of coupling means which comprises said primary winding and a secondary winding, the primary winding being connected in series between the impulse generator and one of said conductors and which obtains the derivative of said current wave form to give a signal output across the secondary winding, and displaying or recording the signal output. The signal output is a pulse of relatively short duration each time a reflection of the voltage impulse returns to the impulse generator. Preferably a digital transient recorder is used for recording the waveform of the resultant reflected signal from the cable.

Remote control arrangement for a medical appliance

Abstract: In a remote control arrangement for a medical appliance, a transmitter and a receiver are provided. The transmitter has a frequency generator controllable by means of code words which generate frequency signals and a group frequency signal alternately. In order to improve the freedom from interference and ease of changing the frequency of the group frequency signal, the frequency generator is constructed to generate a plurality of additional group frequency signals as a function of the feeding one at a time of a corresponding number of different group code words. An impulse generator of the transmitter has two complementary outputs, and the inputs of the frequency generator are connected each through a diode to an output of the impulse generator so that in a prescribed switching state of the impulse generator the potentials corresponding to the binary values appearing at its outputs are connectable to the inputs of the frequency generator through all the diodes poled in the passage direction with reference to the respective potential corresponding to the respective bits of a prescribed group code word.

Incremental impulse generator with timing mark - employing rotating magnets and special alloy detector cores polarised by passage of poles on rotors

Abstract: The pulse generator supplies ignition impulses for an IC. engine. The stator (10) comprises a series of parallel axial wires (11, 12, 13...) of special polycrystalline alloy (Wiegand wire). They are pollarised in one direction or the other by the passage of the magnet poles (19, 20) on the rotor (18). A sharp voltage spike is induced in a winding (17) around the stator each time a wire reverses its magnetic state from one limit to the other. One wire (15) has an additional trigger coil (21) which provides a timing signal for use when setting up the ignition system relative to the engine.

Acoustic impulse generator

Abstract: An acoustic impulse generator is disclosed for use in a fluid media for oceanographic, seismographic and related applications. The generator includes a housing with a piston slidably disposed therein and a passageway through which a rod attached to the piston moves. A firing chamber is attached to the housing for channeling a quantity of liquid through a nozzle. A diaphragm may be disposed between the housing and the firing chamber with the quantity of liquid being displaced in response to movement of the piston.

Electronic speed control for vehicle - has impulse generator delivering signals to counter with flip=flop reset forming independent control

Abstract: The vehicle speed is converted into signal pulses by an impulse generator to feed a counter. When the required speed is reached, the count is stored permanently by comparing the output of the counter, through a resistor array with the output of the signal generator. The counter is controlled by a flip-flop which automatically resets the counter when the ignition is switched off. The control operates independently to variations in the resistors and is unaffected by capacitance drain etc. in the storage circuit.

Voltage transformer for power supplies - uses HF pulse trains controlling driver transistor with amplitude sufficient to ensure transistor is always fully turned on

Abstract: The object of the modified transistor control arrangement is to reduce the losses in the transistors during switching. The driver transistor (T1) is controlled by an impulse generator ( 1). The pulses produced by the generator are composed of bursts of high frequency, and their amplitude is such that the transistor is always fully turned on. The pulse length and repetition rate determine the output from the transformer (W2). The coupling to the main transistor (T2) is through a choke (L) and not a coupling transformer. The choke ensures a steady base current.

Self cleaning dust filter with mechanical action - having metal rings on cylindrical sleeves activated by impulse generator on side

Abstract: Filter elements are mounted vertically in a filter housing and have their open ends directed upwards They have at least one impulse element mounted on their lower ends This serves to collect an impulse transmitted from an impulse generator The filter elements are mounted at such close proximity that a mechanical impulse induces a pendulum motion in the bags and these then bump into neighbouring bags to induce motion in them The impulse element should be located between the lower end and the upper quarter For use with filters for cleaning air or other dust laden gas strains Reverse jet filters are known but damage to bags can be excessive The system described gives mechanical cleaning without costly mountings

Multiple phase network insulation resistance determination - involves pulse generator and filtering detection circuit

Abstract: The equipment is used for determining the insulation resistance of a multiple phase network. It can incorporate rectifiers and direct voltage components using an impulse generator and filtering detection circuit. The device can be applied to single, two or three phase networks. An impulse generator (IG) generates a sequence of pulses which are applied to a typically two phase network (R, S) through a series resistance (RK). A detection circuit (TP) incorporating a low pass filter (C1, C2, L1, L2) and a series of linear amplifiers (IM) together with a number of sequenced switches (S1, S2, S3) provides a reading of the insulation impedance in a suitable meter (M) after filtering out noise, short term effects, and the like.

Electronic impulse switch for wiper motor - has two counters coupled to comparator with one counter set back after second impulse

Abstract: The wiper motor interval switch has an impulse generator with two set back counters connected to a comparator to effect a wiper impulse. A comparator output leads to the set back input of the second counter via an OR-gate. The manual switch input is connected to the wiper impulse transmitter and a bistable regulator switch. The regulator switch is connected to a set back input via a first AND-gate between the impulse generator and the first counter input. The set back output leads to a second AND-gate between the impulse generator and the second counter input.

Hydraulic control system for servomotor - has variable frequency impulse generator to regulate flow valve in supply line connected to pressure vessel and throttled drain passage

Abstract: The hydraulic control system for eg a servo motor has a fluid supply, and a control valve for the flow between the supply and motor the valve is controlled by an impulse generator, which supplies an impulse sequence of variable frequency The flow to the motor (1) varies between max and zero values, a throttle (6) being positioned in the passage (5) between supply and motor Connected to this passage is a drainage passage with throttle (8), and a pressure vessel (7) to even out the flow

Electronic control for vehicle lights - has relay linked to flip=flop driven by impulse generator and reset by signals from feedback loop circuit

Abstract: The vehicle lights are operated by a simple relay (16) linked to a flip-flop (13) and a power switching circuit (14). Operation of the light switch operates an impulse generator (11) to drive the flip flop first to the dipped position and then to the high beam. Successive operation of the light switch changes the setting of the headlamp filaments. The control circuit is provided with a feedback loop to a control circuit (24). This resets the flip flop to the dipped beam setting when the lights are switched off. When the lights are first switched on they are always in the dipped position.

NC machine tool for forming internal worm gear - has spindle coupled to impulse generator supplying tool control circuit to lift tool clear after each cut

Abstract: The machine forms spiral gear teeth inside a hollow cylinder, being numerically controlled, and turning the cylinder by a main spindle. An impulse generator coupled to the spindle supplies a control circuit, determining the point at which the axially-sliding tool begins its cut, in accordance with the desired interval between the grooves. This circuit also lifts the tool clear of the work surface after each cut, and returns it to the starting position for the next cut. The design allows internal spiral grooves to be simply machined with a higher degree of accuracy.

Impulse response testing of acoustic spaces

Abstract: The use of high energy spark discharges to measure the impulse response of rooms will be discussed. Special emphasis will be placed on reverberation measurements, but other measurements will be included. Equipment designed at Rensselaer to simplify and speed this process will be described. This equipment is extremely compact and easily transported enabling field measurements by one person. The methods employed by other researchers will be explained, along with their advantages and disadvantages. Results of actual measurements will be presented and compared to those using more conventional techniques.

Electrode type heater for water - has parallel mounted electrodes cleaned by rotary scraper and supplied through three phase circuit

Abstract: The water heater has electrodes fed from a three phase supply. It comprises a chamber with inlet and outlet, the electrodes being mounted in adjacent parallel pairs. The electrodes are kept clean by a rotary scraper provided with blades which pass over their surfaces. The electrical supply to the electrodes is controlled by an analogues multiplier, a differential output amplifier and, in each phase, a bidirectional thyristor, impulse and current transformers and a variable lag phase control generator. The thyristor is triggered by the impulse generator and transformer and the voltage is proportional to the current and rectified.

A digital control system for HV impulse generators

Abstract: A digital control system using TTL logic elements is described for use with a 1.4 MW impulse generator. The unit is fully programmable and records on magnetic tape the data obtained from breakdown studies of long spark gaps in a form suitable for on-line computer processing. The precautions necessary for operating solid state components in the hostile environment of a high-voltage laboratory include the use of optical links and battery-operated power supplies.

A Digital Timing Unit for Impulse Generator Control

Abstract: This paper describes the design and construction of an impulse generator control unit which uses the counting of predetermined numbers of 10 MHz pulses to fix precise time delays for the control of a high voltage impulse generator and its associated recording equipment. Facilities for "point on wave" firing control are also provided. Particular attention is paid to problems arising from the high "noise levels" likely to occur in the high voltage laboratory environment.

Arrangement for monitoring an oil supply of a lubrication system to be used for heavy machinery

Abstract: An arrangement for monitoring the oil supply of a lubrication system for heavy machinery has an oil supply conduit, a liquid flow counter designed as a toothed wheel counter with two meshing, outwardly-toothed wheels. One of the wheels has a shaft to which a measuring wheel mounted outside of the oil supply conduit is mechanically connected. An impulse generator allocated to the measuring wheel and measuring the rotational speed thereof, an impulse receiver, and a signalling device to which the impulses are led by means of the impulse receiver complete the arrangement.