Showing papers on "Spark (mathematics) published in 1970"

Shock Wave from a Four-Meter Spark

Abstract: The shock wave emitted by a 4‐m spark of energy 2×104 J has been measured at distances from spark midgap of between 0.34 and 16.5 m. Close to the spark, a single dominant shock wave is observed; farther from the spark, a number of significant shock waves (generally 3 or 4) are observed. For distances less than 2 m, both the shock overpressure and the duration of the overpressure are between a factor of 1.5 to 5 less than predicted by cylindrical shock‐wave theory. The discrepancies between the experimental data and cylindrical shock‐wave theory are partially explained by consideration of the spark channel tortuosity.

Engine spark timing control device

Abstract: AN INTERNAL COMBUSTION ENGINE HAS A VACUUM SERVO CONNECTED TO THE DISTRIBUTOR BREAKER PLATE FOR MOVING IT AS A FUNCTION OF THE CHANGE IN CARBURETOR SPARK PORT VACUUM AS CONTROLLED BY A MECHANICAL DEVICE BETWEEN THE SERVO AND SPARK PORT HAVING SINTERED METAL FLOW RESTRICTION AND A ONE-WAY CHECK VALVE IN PARALLEL FLOW CIRCUITS, THE CHECK VALVE UNSEATING DURING RAPID VEHICLE ACCELERATIONS TO QUICKLY REDUCE THE SPARD ADVANCE SETTING TO A LOWER LEVEL, FOR BETTER PERFORMANCE, THE SINTERED METAL FLOW RESTRICTION PROVIDING A DELAYED RATE OF RETURN TO AN ADVANCED SPARK TIMING SETTING DURING RELATIVELY SLOWER ACCELERATIONS, TO MINIMIZE THE EMISSION OF UNDESIRABLE EXHAUST GAS ELEMENTS.

Engine spark timing control device

Abstract: An internal-combustion engine has a vacuum servo connected to the distributor breaker plate for moving it as a function of the change in carburetor spark port vacuum as controlled by a mechanical device between the servo and spark port having sintered metal flow restriction and a one-way check valve in parallel flow circuits, the check valve unseating during rapid vehicle accelerations to quickly reduce the spark advance setting to a lower level, for better performance, the sintered metal flow restriction providing a delayed rate of return to an advanced spark timing setting during relatively slower accelerations, to minimize the emission of undesirable exhaust gas elements

Engine spark timing control system

Abstract: A mechanical device is located between the carburetor spark and intake manifold vacuum ports and the distributor breaker plate servo, the device containing two parallel flow circuits connected to the servo, one being connected to the spark port and containing an orifice, the other being connected to the intake manifold port and containing a servo operated valve that alternately blocks or unblocks the manifold vacuum application to the servo; the orifice providing slow changes in spark advance settings during light vehicle accelerations, and a rapid recovery upon subsequent momentary decelerations; the valve unseating during heavy accelerations to quickly lower the spark advance setting to avoid engine detonation.

Engine spark timing system

Abstract: A mechanical apparatus between the carburetor spark port and distributor servo includes a main one-way check valve is parallel flow relationship with a vacuum reservoir, the reservoir containing an orifice at the servo end and a one-way orificed check valve at the spark port end, the reservoir providing a quick recovery of the engine spark timing setting after rapid acceleration followed by deceleration and reacceleration conditions of operation, to improve fuel economy, the main check valve quickly lowering the spark advance setting during rapid accelerations, and the orifices providing a delayed spark advance during light accelerations.

Spark generator and components therefor

Abstract: A spark igniter for gas fired devices wherein the isolated capacitor of a diode-capacitor voltage tripler is used to store electrical charge for firing the igniter. A timer is used to fire the igniter, whereby peak line current is kept very small. A special circuit is employed to disable the timer when the gas is lit.

Vacuum spark advance cutoff

Abstract: A mechanical device is inserted between the engine distributor servo actuator and the carburetor spark port comprising an atmospheric air bleed controlled by changes in vacuum level in the spark port during vehicle accelerations from an engine idle speed or any speed without spark port vacuum; the bleed immediately moving the spark timing to a maximum retard position. The device consists of a valve to open and close an air vent in response to a power actuator connected to the spark port and having an orifice interconnecting abutting chambers of the power device.

Current-injection spark source for emission spectroscopy

Abstract: An analytical spark gap is provided between the conductors of a resonant line at one end thereof. The other end of the line is connected to a radio frequency power source which can be electronically pulsed. The conductors of the line are preferably in the form of inner and outer coaxial cylinders. The spark gap is preferably between a first electrode at one end of the inner conductor and a second axial electrode connected by means of an end wall to the outer electrode. A current injection input lead is connected to an intermediate point along the line, so as to provide an effective length of one-quarter wavelength between the injection point and the spark gap. In this way, a node is produced at the injection point. Around the spark gap, the outer conductor forms a cylindrical chamber, in which acoustical resonances are set up, with resulting stabilization of the spark in that the spark is held stationary in an axial position. Optical resonance can also be produced within the chamber by providing a cylindrical mirror on the inside of the outer cylindrical conductor around the spark gap.

Circuitry for triggering a spark gap

Abstract: A circuit for triggering breakdown of an arc path through a gaseous atmosphere between a pair of spark gap defining electrodes is disclosed The spark gap includes an auxiliary triggering electrode disposed between the pair of spark gap defining electrodes A voltage divider network is connected across the pair of spark gap defining electrode with the output of the voltage divider being applied to the triggering electrode The voltage divider includes a series connection of a first resistive means and a second resistive means The first resistive means includes one or more four-layer diodes which switch rapidly from a nonconductive state to a conductive state at a certain threshold voltage applied thereacross, whereby when the potential applied across the spark gaping defining electrodes reaches a certain predetermined value the four-layer diodes break into conducting to apply the triggering output potential to the trigger electrode to trigger an arc across the pair of electrodes defining the spark gap

Capacitor discharge ignition system

Abstract: An improved ignition system is provided for an internal combustion engine which is of the capacitive discharge type, and which serves to maintain the engine in tune for long operational periods; and which also serves to improve combustion within the engine so as to prevent the emission of smog-forming, unburned fuel components at all operational speeds of the vehicle in which the engine is installed. The ignition system of the present invention includes a resistance-capacitance discharge circuit which exhibits a relatively high effective spark energy at low cranking speeds of the engine for cold weather starting, yet which exhibits a lower spark energy at higher engine speeds to prevent undue burning of the sparkplugs.

Effects of Changes in Ionization and Attachment Coefficients on the Dielectric Recovery of High-Current Air Gaps

Abstract: Earlier experiments have indicated that the rate of dielectric recovery of high‐pressure, high‐current spark channels is closely related to the fall of gas temperature. Recent experimental measurements of dielectric recovery in air at 1 atm following a critically‐damped 190‐kA spark discharge of 100‐μsec duration have been made. By using measurements of gas temperature and Paschen's law, recovery characteristics have been derived on the assumption that the sole mechanism operative in the post spark channel is the reduction in gas density. It is shown in this paper that temporal variations in the values of the Townsend primary (α), secondary (γ) ionization coefficients, and of the attachment coefficient (a) can account for the detailed discrepancies between measured and derived recovery curves. During the early recovery period, an increase in γ due to the removal of adsorbed gas layers by the high‐current discharge is thought to account for the reduction in recovery voltage below that derived from gas temp...

An Inexpensive, Easily Constructed Spark Cutter for Single Crystals

Abstract: A spark cutter design which is both versatile and very inexpensive is reported. Complete information on all major parts is included. A novice could build the machine in about four days using the information from the note. The spark cutter reported has been used to cut single crystals of a wide variety of metals as well as to do sophisticated machining jobs.

Operating Experience with a Modular Digital Data System for High Energy Physics

Abstract: A modular digital data system originally designed for magnetostrictive wire spark chambers has been expanded to include most digital high energy physics data. The system is built around a 12 bit data bus and has been implemented for a number of computers and other output devices. This paper summarizes three years of operating experience.