Abstract: A method for performing a bakeout test on a vacuum chamber without causing the ion gauge to fail turns the ion gauge off when it is not needed, even during part of the time that the chamber is held at a high vacuum, so as to minimize the opportunity for contaminants to react with and damage the ion gauge filament. Specifically, the method turns the gauge off when any heating elements in the chamber are turned on, so the added heat does not exacerbate the problems with reactions with the filament. Thus, the method turns the gauge off when the chamber is too hot. In one embodiment, the method employs a heating jacket to keep the gauge and its adapter from forming a cold spot at which water vapor can condense during part of the test.

Abstract: An apparatus for monitoring the vacuum of a vacuum switch having at least one vacuum switch tube with a switch chamber and switch contacts is provided. The apparatus has a remotely interrogatable pressure measurement sensor in the form of a piezocrystal or surface acoustic (SAW) device arranged in the interior of the vacuum switch tube and a remote interrogation device placed external to the vacuum switch for monitoring the vacuum via the sensor.

Abstract: There is provided a misfire detecting circuit for an internal combustion engine for detecting a misfire on the basis of the presence or absence of an ion current caused by combustion by applying a voltage to an ignition plug of the internal combustion engine, which circuit prevents malfunction caused by stray capacitance generated in the line up to the ignition plug and by the input impedance of the circuit.

Abstract: A sensitive to a change in the physical dimension(s) of the exterior surface of a pressure vessel transducer and attached to the exterior surface thereof the pressure vessel may be a vacuum chamber. The transducer measures exterior dimension change, representing interior pressure change information, without intrusion. The measurements are displayed using distinctive lights or audible alarms which signal if the pressure inside the vessel is within a predetermined range. If the pressure within the vessel varies outside of the predetermined range, a more precise display device such as a meter, is provided to aid facility personnel in deciding when repairs are necessary.

Abstract: Ionization gauge and method of operating same where the gauge may be of the Bayard-Alpert type and include a shield which completely encloses the electron source, the anode, and the collector electrode so that potentials external to the shield do not disturb the electric charge distribution within the shielded volume to thus stabilize the sensitivity of the gauge. The ionization gauge is further characterized by the following features which may be present either alone or in combination including: (a) the anode is provided with end caps which extend radially inward at least 25% of the radius of the anode but not more than 75% of the radius; (b) the ion collector has a diameter of not less than 0.015 in. and not more than 0.080 in.

Abstract: An improved vacuum valve including an insulating container and an arc shield held in the insulating container, wherein a protrusion is formed on either the outer cylindrical surface of the arc shield or on the inner surface of the container. A detecting electrode is set confronted with the outer surface of the insulating container with an air gap therebetween, and is grounded through a current sensor. The current sensor detects a discharge current which is induced through the protrusion when the degree of vacuum of the vacuum valve is reduced, to output a detection signal. In response to the detection signal, a signal processing unit outputs an alarm signal indicating the reduction in the degree of vacuum of the vacuum valve. Thus, while the vacuum valve is in operation, its vacuum reduction can be positively detected with the vacuum valve maintained unchanged in reliability.

Abstract: A hot cathode ionization pressure gauge with the following electrodes, arged at a distance from one another in the specified sequence along an axis:a) a thermionic cathode filament which has a central active part and lateral support parts;b) an essentially flat, diaphragm-like control electrode,c) an essentially flat apertured acceleration electrode andd) an essentially flat ion collector electrode,and with a base plate on which the control electrode, the acceleration electrode and ion collector electrode are mounted, in each case via support means running at right angles to the main part of the relevant electrode and via a support bolt connected to the support means.

Abstract: A vacuum guage of the ionisation type having a guage head comprising a substantially cylindrical cathode sleeve with an inlet at one end for communication with the vacuum with an anode positioned co-axially within the cathode sleeve; the head also has a guard ring interposed between the cathode sleeve and the anode and a vacuum feed through arrangement in which the anode and the guard ring are held substantially concentrically within the cathode sleeve.

Abstract: A hot cathode ionization pressure gauge with the following electrodes, arged at a distance from one another in the specified sequence along an axis:(a) a thermionic cathode filament which has a central active part and lateral support parts;(b) an essentially flat, diaphragm-like control electrode,(c) an essentially flat apertured acceleration electrode and(d) an essentially flat ion collector electrode,(e) a base plate on which the filament, the control electrode, the acceleration electrode and ion collector electrode are mounted,wherein the base plate consists of a ceramic material and has a plurality of through holes, and each of said control, acceleration and ion collector electrodes comprises a support member having essentially a shape of an inverted "U" with first and second legs, one of said legs of each electrode support member extending through a corresponding hole of said base plate and being fixed therein.

Abstract: Ionization gauge and method of operating same where the gauge may be of the Bayard-Alpert type and include a shield which completely encloses the electron source, the anode, and the collector electrode so that potentials external to the shield do not disturb the electric charge distribution within the shielded volume to thus stabilize the sensitivity of the gauge. The ionization gauge is further characterized by the following features which may be present either alone or in combination including: (a) the anode is provided with end caps which extend radially inward at least 25% of the radius of the anode but not more than 75% of the radius; (b) the ion collector has a diameter of not less than 0.015 in. and not more than 0.080 in.

Abstract: A vacuum circuit-breaker including, for each phase, at least one vacuum bottle housed inside a closed enclosure, wherein said circuit-breaker includes at least one scintillation fiber disposed in the space between said enclosure and the outside surface of the vacuum bottle(s), said fiber being connected outside the circuit-breaker to an opto-electronic device.

Abstract: Ionization vacuum gauge comprising, like Bayard Alpert gauges, in a chamber (1) containing an extremely low pressure atmosphere, whose ultra-vacuum degree it is desired to be measured, an electron source cathode (2), a grid (3) for collecting these electrons and surrounding a collector (4) of ions resulting from the impact of the electrons on the gas molecules of the extremely low pressure atmosphere, wherein the electron source is a cold micropoint cathode.

Abstract: A capacitor is connected to an ignition coil for an internal combustion engine so as to be charged by ignition current generated by the ignition coil. After firing of a spark plug in a cylinder by the ignition current, the voltage across the capacitor is applied between the center electrode and the ground electrode of the spark plug to induce an ionic current between the electrodes. The resulting ionic current is measured by a current sensor connected to the capacitor.

Abstract: Controller circuitry and method for controlling the operation of an ionization gauge having a source of electrons, an anode, and an ion collector electrode, including storing a plurality of calibration data sets for at least collector electrode currents and gauge sensitivities obtained with at least one reference gauge at representative values of known pressures; and calculating the gauge sensitivity corresponding to an unknown pressure in response to at least one of the data sets together with a measured value of the ion collector current. The data sets may also include representative values of the heating powers of the electron source so that the calculated sensitivity may also be compensated for variations in the electron source heating power.

Abstract: A cold cathode gauge including a glow lamp or the like disposed within the vacuum space of the gauge for initiating the gauge discharge, the lamp emitting UV or blue light directly at at least the cathode of the gauge where the energy of the light is sufficient to release photoelectrons from the cathode to thus initiate the discharge. A member is also provided for removably positioning the glow lamp within the vacuum space whereby the lamp can be removed during bake out and then subsequent thereto, be inserted within the vacuum space to thus enhance longevity of the lamp.

Abstract: The invention relates to a measured value pickup for vacuum measurements, with the pickup including a sensor as well as electronic circuits for supplying the sensor with voltage, and a signal processing device. In order to be able to employ the measure value pickup independently of the location of the measured value processing system, it is proposed to configure it as a transmitter.

Abstract: A cold cathode gauge including a glow lamp or the like disposed within the vacuum space of the gauge for initiating the gauge discharge, the lamp emitting UV or blue light directly at least at the cathode of the gauge where the energy of the light is sufficient to release photoelectrons from the cathode to thus initiate the discharge. Various techniques for supplying power to the lamp are also disclosed.

Abstract: A low pressure, low energy measuring device for indirectly and non-invasiy measuring the pressure of a gaseous medium in a sealed system, such as gas discharge lamp, is disclosed. The measuring device and method measures the luminance of an externally-induced, high-frequency glow discharge of a gas in the lamp by non-invasive means. Comparison of the measured luminance with calibrated luminance vs. pressure data provides the pressure for the gas. In one embodiment, the components of the measuring device form a stand-alone unit useful for testing multiple sealed systems. In another embodiment, certain components of the device are integrated into the lamp's discharge system to facilitate measurement in the field. A separate peripheral unit is required with this latter embodiment.

Abstract: An improved electronic device allows for the feeding of an ion pump with a plurality of voltages that are changed as a function of the current drawn by the pump and therefore of the pressure value within the pump.

Abstract: Apparatus for measuring the concentration of one material such as water in another material such as crude or refined oil including a coaxial microwave transmission line formed by a conduit for receiving the material and a center conductor which is sheathed with a dielectric covering which is operable to prevent short circuiting of the transmission path. An oscillator circuit is coupled to the transmission line and is driven by a free-running voltage controlled oscillator and a signal receiver monitors the change in frequency caused by impedance pulling of the oscillator due to the change in the dielectric constant of the mixture. Incident and reflected or transmitted power with respect to the measurement section is measured to determine whether an oil-in-water or water-in-oil emulsion is present to verify the concentration of one fluid in the other for a particular operating frequency.

Abstract: A method and circuit for measuring the pressure of a gas with a cold cathode ionization gauge by measuring the electrical resistance or conductance of the gauge to thus extend the measurement range of the gauge. Current into the gauge may be limited to a substantially constant value at pressures greater than about 10.sup.-6 Torr, for example, so that the gauge voltage varies monotonically with respect to pressure at pressures greater than 10.sup.-6 Torr.

Abstract: To check the presence of operating vacuum in vacuum switches, high voltage can be applied between the contacts at a given contact spacing and the dielectric strength can be tested. According to the invention, the procedure for vacuum monitoring is that a contact spacing (h) below the nominal stroke of the vacuum switch is selected and that the X-radiation generated at this contact spacing (h) and high voltage (U) in vacuum due to the field electron emission between the contacts by the contact surfaces acting as anode is acquired and evaluated as proof of the presence of operating vacuum inside the switching tube. This method can preferably be applied to encapsulated vacuum switching tubes, in particular to SF.sub.6 -insulated switching facilities.

Abstract: A gas ionization type vacuum gauge for testing the internal vacuum levels to below 10.sup.-6 torr is disclosed which uses a multipactor discharge means as the source for the electron current used to ionize residual gas molecules. The invention comprises an RF field enhancing cavity which can be constructed of high-vacuum-compatible materials, able to withstand bake-out microwave temperatures and a negatively biased ion collection wave, wire, or grid. A simple ceramic RF feed-through permits simple and noninvasive pressure measurements. The device can be made much smaller than conventional gauges.

Abstract: A manual apparatus for testing the vacuum of an evacuated vial. A cylindrical test enclosure having an access opening in the wall thereof is provided for the vial. A rotatable sleeve surrounds the enclosure and has a like access opening in registration with and rotatable to be in alignment with the access opening of the test enclosure. When the two access openings are rotated out of alignment, high voltage radio frequency power is applied to the exterior of the vial, and an intense flash of light occurs next to the vial to cause ionization of gas within the vial. The ionization current which results is indicative of the value of the vacuum within the vial.

Abstract: The invention relates to a method and an arrangement for detecting ionizing current in an ignition circuit incorporated in the ignition system of an internal combustion engine, in which a measuring voltage is applied to the ignition circuit in at least one secondary winding, and in which a measuring device is used to detect the possible presence of an ionizing current in the ignition circuit. A low measuring voltage is applied during an engine start sequence, or alternatively, no measuring voltage at all, and a high measuring voltage is applied subsequent to the engine start. The invention thereby overcomes the problem existing when measuring ionizing currents of the spark plugs becoming coated with soot deposits as a result of the electrical voltage field which always exists between the electrodes of respective plugs. Such problem is particularly troublesome during an engine start sequence, since the deposits can prevent the engine from starting.

Abstract: A cold-cathode ionization or Penning vacuum meter with an ignition system to increase the meter's usefulness at very low pressures. The ignition system comprises an additional anode and at least one additional cathode mounted adjacent to the primary, measuring, cathode and anode and within the same magnetic field as the primary cathode and anode. The at least one additional cathode and the anode are substantially smaller than the measuring cathode and the anode and serve to ignite or start the ionization of the atomosphere whose pressure needs to be measured.

Abstract: A hot cathode ionization gauge with which neutral gas densities in the ra 10.sup.17 to 10.sup.21 m.sup.-3 can be measured, in particular under the conditions typical of fusion-orientated plasma experiments (magnetic field strength from 0 to more than 3 tesla, magnetic field direction varying by up to +/-20 degrees or more and strong plasma-induced noise background), and which is of robust design, reliable in operation and very compact and has a high sensitivity which depends in a reproducible manner on the magnetic field strength and is independent, in a certain degree which is predetermined and can be influenced by the construction, of the field direction and, within a wide range, of the gas density comprises the following electrodes arranged in mutually spaced relationship in the stated order along an axis: a cathode consisting of a tungsten wire at least 0.

Abstract: Regarding a gas pressure gage for measuring a gas pressure in a vacuum chamber of a semiconductor element manufacturing apparatus, or the like, the present invention has made it possible to attain a small-sized and unitary gas pressure gage and to implement a thorough measurement of gas pressure from the atmospheric pressure to a high vacuum of about 10.sup.-10 Torr, by mounting both a mechanical vibrator type pressure gage and an ionization type pressure gage on a flange provided for fitting a chamber and by providing a control circuit for making the former gage operate in a low-vacuum region and the latter in a high-vacuum region.

Abstract: An electronic device for feeding an ion pump with two different tensions and for improved measuring of the pressure in the pump, the two different tensions being a normal operating tension and a lower tension at which a correct measurement of the pressure can be made in a pressure range up to beyond 10.sup.-10 torr. through a transformer whose primary or secondary winding is divided into two sections that can be connected and separated by switches controlled by oscillator circuits. Alternatively feeding at two different tensions can be obtained by feeding to the primary winding of the transformer a pulsed tension having a rectangular wave form and a high frequency controlled by a field effect transistor having an isolated gate. A sampling and holding circuit permits the pressure to be measured only in the conditions of feeding at the lower tension.

Abstract: A device for measuring the internal pressure of an operationally built-in vacuum switch which comprises a vacuum switching tube having a switching chamber and switch contacts as well as an associated drive for the contacts. For the measurement of the pressure, a cold-cathode discharge (so-called Penning effect) having crossed electric and magnetic fields is used, wherein the electric field is applied, for instance, between at least one of the switch contacts and a metallic wall of the switching chamber or a condensation shield disposed in the chamber and permanent magnets are used for generating the magnetic field. The permanent magnets are realized in the form of rods and have pole pieces formed such that the pole pieces encircle the switching chamber. A magnetic field is formed which is applied directly in the longitudinal direction to a circumferential section of the cylindrical switching chamber.

Abstract: A vacuum gauge includes a quadrupole mass spectrometer for measuring an ion current value of respective gas components, the Bayard-Alpart type ionization gauge for measuring an apparent total pressure value of the gas components, an arithmetic logic unit for calculating a predetermined equation so as to obtain concentration of the respective gas components and also measurement sensitivity of the respective gas components, whereby the apparent total pressure value is corrected, based upon the measurement sensitivity of the respective gas components, to derive a real total pressure value of the measured gas components.

Abstract: A process and apparatus for testing the degree of vacuum in an evacuated vial. For testing the vacuum, a vial is located at a source of high voltage radio frequency power and the power is applied to the vial. A momentary intense flash of light is applied to the vial to cause ionization of the gas within the vial and the ionization current of the ionized gas within the vial is then sensed and a representation of the value of the ionization current is generated. The representation of the ionized current is compared with a minimum acceptable current value which is indicative of a predetermined minimum allowable vacuum within the vial. The vial is rejected if the measured ionization current is less than the minimum acceptable current value. In one embodiment, the apparatus includes a single station for testing evacuated vials, one at a time. In another embodiment of the apparatus, a plurality of vials are conveyed in a carousel through a series of testing stations.

Abstract: The primary winding of an engine ignition coil is coupled to an ionization probe detecting cylinder combustion in order to apply a bias voltage.

Abstract: There is provided a novel vacuum detection means utilizing a high frequency, high voltage device to excite an electrical discharge in a vacuum whose characteristics are dependent on the level of the vacuum contained therein. This discharge current allows the degree of vacuum to be continuously monitored.

Abstract: A leak detector comprising a housing having an axis on first and second compartments spaced along the axis and hermetically separated by a partition, the first compartment being closed to comprise a pressure envelope which is in communication with an evacuated space to be monitored for leakage, an ionization cell in the first compartment providing an electrical current determined by gas in that compartment, hermetically sealed feed-through for enabling an electrical connection with the gauge, to the partition from the second compartment, an apparatus in the second compartment performing a control function in accordance with the current supplied by the cell.

Abstract: A voltage source for measurement of pressure fluctuations in internal combustion engine cylinders by current detected between the electrodes of the sparkplug after the spark has died down, is derived from the ignition voltage. A capacitor can be charged to a voltage of a few hundred volts for this purpose in various ways, and either a positive or a negative measurement voltage can be provided with respect to ground across a measuring resistor for further processing. Very few additional components are required. It is possible to provide a voltage that is continuously available for the convenience of timing the measurement and for the capability of making the measurement and all of the cylinders of the engine.

Abstract: The operating range of an ionization tube vacuum gauge is increased by applying at least two different bias voltages to the tube and measuring ion current for the two bias voltages. The ratio of the ion currents indicates vacuum pressure in the range of 10.sup.-1 to above 2 Torr. An ionization tube vacuum gauge provides a pressure read-out by the linear ion current response of an ionization tube between 10.sup.-10 Torr and 10.sup.-2 Torr. The non-linearity of the ion current response between 10.sup.-2 Torr and 10.sup.-1 Torr is compensated by a non-linear amplifier. Above 10.sup.-1 Torr the ratio of ion currents is utilized for determining pressure.