Abstract: A device to read a variable resistor has an analog to digital converter (ADC), a first switch and a second switch. The ADC has a first ADC input, a second ADC input and an ADC output. The first switch selectively couples a first voltage indicative of a voltage across a first resistance to the first ADC input. The second switch selectively couples a second voltage indicative of a voltage across a second resistance to the second ADC input. The ADC outputs a signal indicative of a value of the second resistance.

Abstract: A method of measuring squib loop resistance including non-linear elements in a restraint control module is disclosed by the present invention. The squib loop resistance is comprised of both linear and non-linear elements. The non-linear elements are linearized into resistive components about the bias points used to make the squib loop resistance measurement. The calculation of the linear squib loop resistance is provided by comparing the complete squib loop resistance and the linearized value of the non-linear elements.

Abstract: To provide the user of an RF-surgical instrument with a non-hazardous short test operation, for example so as to test the ignitability of an argon plasma probe, provision is made for an instrument test arrangement, which is installed into a feeding medical device or into a neutral conductor connecting cable or which is provided as plug adapter, which is to be plugged between the device and the neutral conductor connecting cable. The instrument test arrangement comprises at least one or, better yet, two ignition test electrodes, which are connected to conductors of the device or of the neutral conductor cable, preferably via impedance components. The ignition test electrodes can be accessed insofar as a spark can be created simultaneously to both ignition test electrodes by means of an operational probe or an instrument.

Abstract: Various embodiments for detecting a high Intensity radiated field (HIRF) in a line replaceable unit are provided. In an embodiment, the internal detector comprises a receiving means for receiving HIRF and generating an AC signal proportional to the HIRF, an RF filter configured to sample the AC signal to create a DC signal; and a detecting section configured to compare the DC signal with a threshold and output a result of the comparison to a built-in test section. The internal detector may be used to test EMI filter pin connectors of a closed line replaceable unit.

Abstract: A biological information detector includes a first sensor unit for detecting composite information including biological information of a test subject and first noise information originating in external light, having a first light-emitting part for emitting toward there, a first light-receiving part for receiving it including the biological information, reflected there, and the light including the first noise information obtained from the external light, transmitted through there, and a first reflecting and leading part for reflecting the light including the biological and the first noise information, leading it to the first light-receiving part, and a second sensor unit for detecting second noise information originating in the external light, having a second light-receiving part for receiving the light including the second noise information, obtained from the external light and transmitted through there, and a second reflecting, leading part for reflecting the external light and leading it to the second light

Abstract: A method of measuring squib loop resistance including non-linear elements in a restraint control module is disclosed by the present invention. The squib loop resistance is comprised of both linear and non-linear elements. The non-linear elements are linearized into resistive components about the bias points used to make the squib loop resistance measurement. The calculation of the linear squib loop resistance is provided by comparing the complete squib loop resistance and the linearized value of the non-linear elements.

Abstract: The present invention is to provide a power supply control apparatus which can connect a ground to a suitable electric potential when the ground is disconnected. The power supply control apparatus includes a control circuit having a switch element and a switch control unit, and a load. One terminal of load is connected to a direct-current power supply through the switch element, and the other terminal is connected to a ground electric potential. The switch control unit has a ground terminal connected to the ground electric potential and outputting a ground current flowing toward the ground electric potential. The control circuit includes a bypass device having a load side bypass system for passing the ground current to the ground electric potential through the load when connection between the ground terminal and the ground electric potential is disconnected.

Abstract: A device has built-in inductive load testing capabilities. The device includes a device housing, an inductive load disposed within the device housing; and test circuitry disposed within the device housing. The test circuitry is constructed and arranged to effectuate application of a modulated test signal to the inductive load, and obtain a result signal in response to the application of the modulated test signal to the inductive load. The test circuitry is further constructed and arranged to generate an output signal indicating that the inductive load is in one of (i) a shorted inductive load state, (ii) a normal inductive load state, and (iii) an abnormally high inductive load state, based on the result signal. Such test circuitry is well-suited for testing a variety of devices having inductors/coils which are susceptible to defects (e.g., a solenoid, a motor winding, various actuator components, etc.).

Abstract: In an electronic apparatus in which plural substrates are arranged in a perpendicular direction between plural cooling fans in a lower part of a case and plural temperature sensors in an upper part of the case, any temperature variation by 2° C. in three seconds detected by any one of the temperature sensors is determined to be abnormal, and thermal energy is caused to be discharged from surfaces of substrates on two sides of a flame by raising air flow rates of fans. Expansion of the flame to other substrates is thereby prevented.

Abstract: A system for detecting spark in an igniter for a gas turbine engine. An igniter generates a plasma, or spark, somewhat similar to an automotive spark plug. In the invention, an inductive pick-up is positioned adjacent the igniter, to detect current pulses in the igniter, to thereby infer the presence of spark. A detection system detects the spark, and informs the pilot of the aircraft of the detected spark. Thus, if the pilot encounters a problem in starting the engine, the pilot can rapidly determine whether the igniter is involved in the problem.

Abstract: A measuring device and a measuring method for non-destructive testing of an ignitor installed in a subassembly, particularly of a motor vehicle. The device and measuring method generate a measuring current with a predefined value, check-test the predefined value of the measuring current while bypassing the ignitor, apply the check-tested measuring current to the subassembly with the installed ignitor for a predefined time interval, determine the internal resistance of the subassembly with the installed ignitor, and derive a test signal indicating the installation condition based on a comparison with a setpoint value.

Abstract: A system for detecting spark in an igniter for a gas turbine engine. An igniter generates a plasma, or spark, somewhat similar to an automotive spark plug. In the invention, an inductive pick-up is positioned adjacent the igniter, to detect current pulses in the igniter, to thereby infer the presence of spark. The pick-up can take the form of a coil embedded in a mounting bracket which is used to fasten the igniter to the engine.

Abstract: An igniter for a gas turbine engine. An igniter generates a plasma, or spark, somewhat similar to an automotive spark plug. In the invention, an inductive pick-up is used to detect current which produces the spark, the thereby infer the presence of spark. Further, the sensor is located directly adjacent the igniter, in a hot environment, often exceeding 400 F.

Abstract: An apparatus for measuring the resistance of a squib, including an input for receiving a power supply and a circuit connected to the input for limiting the power supplied to the squib. The circuit includes a voltage limiter which limits voltage output of the circuit to a level insufficient to ignite the squib, and a current limiter for limiting the current output of the circuit, the current limiter being responsive to a current supplied upon activation of the voltage limiter to limit the total energy supplied by the circuit to a predetermined level following activation of the voltage limiter. The voltage limiter can be a parallel arrangement of diodes connecting first and second conductive leads. The current limiter can include fuses which open when diodes conduct current through the conductive leads. This apparatus prevents squib activation even if an overcurrent or overvoltage occurs in the ac power supply.

Abstract: An apparatus for measuring the resistance of a squib, including an input for receiving a power supply and a circuit connected to the input for limiting the power supplied to the squib. The circuit includes a voltage limiter which limits voltage output of the circuit to a level insufficient to ignite the squib, and a current limiter for limiting the current output of the circuit, the current limiter being responsive to a current supplied upon activation of the voltage limiter to limit the total energy supplied by the circuit to a predetermined level following activation of the voltage limiter. The voltage limiter can be a parallel arrangement of diodes connecting first and second conductive leads. The current limiter can include fuses which open when diodes conduct current through the conductive leads. This apparatus prevents squib activation even if an overcurrent or overvoltage occurs in the ac power supply.

Abstract: A capacitance of a firing capacitor for the firing of a firing pellet, where the firing capacitor is contained in an occupant protection system of a motor vehicle, is implemented on a rising edge of a capacitor voltage in a charging phase. For this purpose, a quantity of charge taken up by the storage capacitor during a test time interval is determined by measurement of a charge current or of a corresponding value and integration over the test time interval. The capacitance is obtained through a quotient of the resultant integral and a voltage change in the capacitor voltage that occurred in the test time interval. The functional availability of the firing capacitor is not adversely affected at any time during the testing.

Abstract: The resistance value and the leakage current of a load can be measured simultaneously. A load current is fed, mirrored by electrical power supplies (1, 3, 36), into a resistance measuring circuit (13, 30) and a leakage current measuring circuit (14 to 16). This permits rapid, precise measurement of a plurality of loads by a single measuring circuit connected via one multiplexer. The firing transistors can be distributed among different ASICs or provided jointly for a plurality of firing caps.

Abstract: A device for triggering ignition circuits is used to increase safety without additional expenditures in the form of hardware or wiring. Plus and minus output elements of various ICs are used for this purpose. Ignition circuit diagnosis is now also distributed over two ICs. Ignition circuit diagnosis includes, in particular, the resistance measurement of the respective ignition circuit. Each substrate, in other words IC, therefore has at least one plus and one minus output element.

Abstract: An ignition coil with an isolated internal lead in proximity to the secondary side can be used in a capacitive discharge ignition system with a microprocessor-based signal-processing module to monitor system performance. The diagnostic lead is fed into a diagnostic signal interface circuit that provides a logic edge to the microprocessor when the spark plug fires. By measuring the time from the firing signal provided by the microprocessor to the logic edge provided by the diagnostic signal interface circuit, the precise energy necessary to fire the plug can be determined. An ignition system that includes an ignition coil with a diagnostic lead can extend spark plug life by automatically adjusting spark energy to minimize wear on the spark plug.

Abstract: The ohmic resistance of a firing element connected in series to a capacitance is measured by charging the capacitance with a measured current for a specifiable charging time, by recording a first firing circuit voltage which drops at the firing circuit at the end of the charging operation and by recording a second firing circuit voltage after the measured current is disconnected and by determining the resistance of the firing element from the two firing circuit voltages and the measured current. An exact measurement of the resistance of the firing element regardless of capacitance fluctuations is made possible in that the charging time for the capacitance of the firing circuit is rated in such a way that the second firing circuit voltage corresponds to a setpoint value.

Abstract: An arrangement that can be implemented with a simple circuit includes a measuring resistance that can either be connected in addition to a load or connected in place of the load. Furthermore, elements are provided that record the change in resistance resulting from the connection of the measuring resistance and signal when the change in resistance differs from a predefined value.

Abstract: The present invention is directed to a squib fire network including built-in testing which is able to safely and efficiently verify the proper operational status of the squib fire network. All squibs in a given squib fire network of a missile can be tested prior to launch, thereby improving the reliability of weapon deployment.

Abstract: In an arrangement that can be implemented with a simple circuit, the load is connected in parallel to an additional resistor. The primary-side input resistance of the transformer is measured, and when the input resistance differs from a predefined value, a load malfunction is signaled.

Abstract: A programmable voltage divider has normal and test modes of operation. The divider includes first and second supply nodes, a divider node that provides a data value, and a first divider element that is coupled between the first supply node and the divider node. The divider also includes a controlled node, a second divider element that has a selectable resistivity and that is coupled between the divider node and the controlled node, and a test circuit that is coupled between the controlled node and the second supply node. During the normal mode of operation, the first and second divider elements generate the data value having a first logic level when the second divider element has a first resistivity, and generate the data value having a second logic level when the second divider element has a second resistivity. The test circuit generates a first voltage at the controlled node during the normal mode of operation, and generates a second voltage at the controlled node during the test mode of operation.

Abstract: This invention provides a method and electronic circuits for the testing of new initiation devices that use a small transformer whose heating element resistance can not be measured using traditional methods and instruments. A small current testing signal is applied to the primary winding of the detonator through its leg wires that are connected in a certain circuit configuration. The resistance of the secondary winding connected with the bridge wire is then reflected to the primary side and its effects are then observed. By calibrating the relationship of such effects with the value of loop resistance, the loop resistance can he displayed. Since the testing signal is very small in nature for safety considerations, the sampled effects (generally the voltage wave) are amplified. The amplified effects are displayed with analogue or digital meters or other display means.

Abstract: A circuit configuration for measuring resistance and/or leakage between two nodes, which includes a current source for feeding a test current into one of the two nodes and a circuit element that detects the voltage resulting between the two nodes. The output of a broadband signal generator is connected to a control input of the current source. The outputs of the circuit element and of the signal generator are connected to the inputs of the correlator for determining the correlation between their output signals.

Abstract: The invention concerns a method for the recognition of insulation defects in a circuit adapted for connection to a low-ohmic current source or sink having off-load voltage U.sub.n0, Towards this end the circuit is initially subjected, in a separated state, to a diagnostic voltage from a current limited current source or sink whose off-load voltage U.sub.h0 corresponds to exceeds or, respectively, is less than the voltage U.sub.n0. A decision is made as to the presence or absence of an insulation defect based on the current and/or voltage dependence during application of the diagnostic voltage. Finally, in the event that a defect is present, an error message is issued and the low-ohmic current source or sink is not connected to the circuit for self-diagnosis. Otherwise, the low-ohmic current source is connected to the circuit, or the sink, in sequential fashion for self-diagnosis testing. In this fashion even hidden insulation defects are recognized.

Abstract: A method for measuring the resistance of a load, preferably the firing pellet of an airbag, that is connected on the secondary side of a rotary transformer, in which the resistance measurement is largely unaffected by the magnetic coupling between the windings of the transformer. According to this method, the capacitor is partially discharged twice in succession. During the first partial discharge, the capacitor is discharged continuously, and during the second partial discharge, the capacitor is discharged in steps. After the two partial discharges, the residual charge voltages at the capacitor are measured and the difference between the two charge voltages is obtained. This difference is an indication of the resistance of the load connected on the secondary side of the transformer.

Abstract: A method of assembling an igniter (24) for a gas generating composition (18) comprises providing a pair of spaced apart electrodes (40 and 42) and providing a heat ignitable material (46). A heating element (44) is spot electrical resistance welded to the electrodes (40 and 42). The heating element (44) has flattened portions (110 and 112) at the spot welds (102 and 104) and a central portion between the spot welds (102 and 104) adapted for contact with the heat ignitable material (46). A test level of electric current is directed between the electrodes (40 and 42) and through the heating element (44) and the spot welds (102 and 104) at a level effective to heat the heating element (44) and the spot welds (102 and 104). The level infrared radiation emitted by the heating element (44) and the spot welds (102 and 104) is sensed, throughout a scanned field which fully encompasses the heating element and the welds, under the influence of the test level of electric current.

Abstract: A method is provided for locating failures in a sequentially arranged chain of detonation devices. The method comprises initiating a test signal and passing this signal sequentially along the chain from each correctly operating detonation device to the next after a predetermined delay at each device; monitoring the chain of detonation devices by receiving a confirmation signal from each correctly operating device which has received the test signal; and ascertaining the last device to have received the test signal by a cumulative count of the number of detonation devices which have received the test signal.

Abstract: A circuit continuity test device is disclosed. The device utilizes a series circuit to provide a completed circuit for an external explosive or pyrotechnic circuit. The series circuit has a switch in the form of a light emitting diode and a power source. Upon coupling to a continuous external circuit, the diode is placed in an on state thereby illuminating and indicating a continuous external circuit.The device housing is a simple, compact and solid part. This allows the device to be used in a variety of environmental conditions and easily and inexpensively manufactured.

Abstract: A passenger protection apparatus is provided with a plurality of squibs (activating elements). Transistors are respectively connected in series to these squibs. By switching on these transistors at predetermined differing timing, first monitor currents are conducted via current-controlling resistors to the respective squibs. First monitor currents can be independently conducted to the respective squibs with this structure. For this reason, the voltage levels generated at the squibs by the first monitor currents can be enlarged. Resistance values of the respective squibs can be calculated with high accuracy from these voltage values.

Abstract: A dual-type pyroelectric elements. The first pyroelectric element is constituted by a larger electrode on a first surface and a smaller electrode on a second surface, respectively of a pyroelectric sheet. The second pyroelectric element is on the other hand constituted by a smaller electrode on the first surface and a larger electrode on the second surface respectively of the pyroelectric sheet. Further, takeout electrodes are taken out respectively integrally from the smaller electrodes on both surfaces of the pyroelectric sheet in mutually opposite directions.

Abstract: An apparatus for failure identification suitable for determining between existence and nonexistence of failure of the squib in occupant protecting system. The first terminal voltage generated between both the terminals of the squib when the first monitor current is passed through the squib, and the second terminal voltage generated between both the terminals of the squib when the second monitor current is passed through the squib. The first and second terminal voltages are amplified by the differential amplifier circuit into the first and second differentially amplified voltage. Thereafter, the difference between the first differentially amplified voltage and the second differentially amplified voltage is calculated to obtain the monitor voltage difference and it is compared with the reference voltage, and thereupon, decision between existence and nonexistence of a short-circuit in the squib is made.

Abstract: A process for mapping the path of an electric arc through a sample of resive material whereby the magnetic field propagated by the arc is recorded on a sleeve of magnetic sensitive material which surrounds the sample, with the intensity of the recorded field at different points on the sleeve indicating the path of the arc.

Abstract: An apparatus and method for testing the ignition modules of gas burners is disclosed, and functions without the requirement of a gas feed in the test program. The method involves disconnecting the ignition module from the electrical supply, and from the gas feed, and employing the apparatus of the invention to apply a test voltage to the ignition module, and to various individual components of the system such as the pilot gas valve and main gas valve which are encased in the gas valve, connecting wires, etc. In order to avoid employing gas feed in the test, a simulated gas flame signal is fed to the ignition module under test using a flame simulator device which sends an appropriate signal to the ignitor module. Hence, with the gas feed disconnected, the test method and apparatus of this invention can be used to conduct the test safely, while saving time, and providing a reliable result.

Abstract: The self-contained diagnostic system is provided for a stroboscopic light circuit. The diagnostic system includes a plurality of signal lights, preferably LEDs, connected at various locations in the circuit to provide a visual indication of the faulty portion of the circuit in the event that the circuit does not operate properly. The system provides a quick and easy method for determining the location of a malfunction of a stroboscopic light without the necessity of replacing the entire light system or the use of diagnostic equipment.

Abstract: Load resistors connected in parallel in a heating circuit having switches operable to connect and disconnect the resistors from a common supply line for heating a plurality of zones to maintain predetermined temperatures therein, are tested by disconnecting all of the load resistors from the supply line to begin a testing operation. Any current conducted when all load resistors are disconnected from the supply line is measured, after which the load resistors are then individually and successively reconnected to the supply line. The current then conducted from the supply line in succession to the load resistors is measured and compared with reference values of current through the load resistors when functioning properly.

Abstract: A four-terminal electrical connector device (40) for testing and measuring unknown resistances of initiators (11) used for starting pyrotechnic events aboard a Space Transportation System. The testing device minimizes contact resistance degradation effects and so improves the reliability of resistance measurement taken with the device. Separate and independent voltage sensing (19) and current supply (20) circuits each includes a pair of socket contacts (13-16) for mating engagement with the pins (17,18) of the initiator. The unknown resistance that is measured by the device is the resistance of the bridgewire (23) of the initiator which is required to be between 0.95 and 1.15 ohms.