Abstract:
PROBLEM TO BE SOLVED: To provide a cold cathode ionization vacuum gauge for triggering discharge in a short time even when using over a long period of time without complicating an apparatus. SOLUTION: The cold cathode ionization vacuum gauge includes the structure in which a rod-like anode 2 is located in an internal part of a measuring element container (cathode) 1 having a discharge space 9 whose one end is sealed, and a discharge starting auxiliary electrode 5 is mounted on this anode 2. The discharge starting auxiliary electrode 5 triggers the discharge in a short time by the formation of a carbon nano tube layer 10 on a discharge starting auxiliary electrode plate 7. COPYRIGHT: (C)2011,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide an ionization vacuum device protecting an electrode against contaminants in a vacuum vessel. SOLUTION: The ionization vacuum device includes: a vacuum vessel 13; an anode 11 provided in the vessel 13, cathodes 12a and 12b provided in the vessel 13; a discharging power source 19 for supplying discharging power into the anode 11 and the cathodes 12a and 12b; a cathode heating power source 18 for supplying heating power to the cathode; and means 16a and 16b for forming a magnetic field between the anode 11 and the cathodes 12a and 12b. The device connects the vacuum vessel 13 with another vacuum vessel to measure a pressure in the latter vacuum vessel or evacuates the latter vacuum vessel. The device is characterized in that it includes a control means for heating the cathodes 12a and 12b by the cathode heating power source 18 while causing a gas in the vacuum vessel 13 to discharge, and keeping a temperature in the cathodes 12a and 12b within a temperature range where thermo-electrons are not emitted from the cathodes 12a and 12b. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
Eine lonisations - Vakuummesszelle umfasst: a) ein evakuierbares Gehäuse (10) mit einem Messanschluss (8) für das zu messende Vakuum, b) eine erste äussere und eine zweite innere Elektrode (3, 4), die koaxial und beabstandet zueinander angeordnet sind mit einer gemeinsamen Achse (7), wodurch zwischen diesen beiden Elektroden eine Messkammer (20) ausgebildet ist, die mit dem Messanschluss (8) kommuniziert, c) einer Spannungsquelle (16), die mit den Elektroden (3, 4) verbunden ist, d) ein Strommessmittel (17) zur Auswertung eines Entladungsstromes ausgebildet zwischen den Elektroden (3, 4), e) mindestens einen Permanentmagnetring (1), der die koaxiale Anordnung der Elektroden (3, 4) umschliesst, mit radial zur Achse ausgerichteter Magnetisierungsrichtung (13) und mit einem diesen Permanentmagnetring (1) umschliessenden weichmagnetischen Joch (2), wobei das Joch (2) in axialer Richtung beidseitig vom Permanentmagnetring (1) weg geführt ist und nach einem vorgegebenen Abstand (d) vom Permanentmagnetring (1) auf beiden Seiten in radialer Richtung zur Achse (7) und der ersten Elektrode (3) hin geführt ist, derart dass das Joch (2) beidseitig, beabstandet vom Permanentmagnetring (1) zwei ringförmige Pole (9a, b) ausbildet über welche mindestens ein Teil der Feldlinien des Permanentmagnetringes (1) sich innerhalb der Messkammer (20), die erste Elektrode (3) durchdringend, schliessen.
Abstract:
An ionization gauge includes an electron generator array that includes a microchannel plate that includes an electron generating portion of the microchannel plate comprising a source for generating seed electrons and an electron multiplier portion of the microchannel plate, responsive to the seed electrons generated by the electron generating portion, that multiplies the electrons. The ionization gauge includes an ionization volume in which the electrons impact a gaseous species, and a collector electrode for collecting ions formed by the impact between the electrons and gas species. The collector electrode can be surrounded by the anode, or the ionization gauge can be formed with multiple collector electrodes. The source of electrons can provide for a spontaneous emission of electrons, where the electrons are multiplied in a cascade.
Abstract:
A gauge head (10) for an ionisation vacuum gauge includes an electrical device (12, 28, 54) operable to provide an electrical discharge in a gas whose pressure is to be measured to initiate ion discharge in the gas.
Abstract:
A cold cathode ion gauge is provided that is suitable for use in a high vacuum and in the presence of contaminating gases. By decreasing the discharge current and, more precisely, decreasing the charge current density received by the gauge electrodes, and using certain type of materials for the gauge electrodes, the mechanism by which insulating films are deposited on surface of the electrodes is attenuated and the life of the gauge is significantly prolonged. The gauge discharge current can be decreased by providing a large resistor in series with the anode, while the charge current density can be decreased by using an electrode with larger surface area, which can be achieved by fabricating grooves or fans on electrodes and by using low electron backscattering and low secondary emission materials, like carbon. Another concept of constant current mode is also proposed in this invention for extending the lifetime of CCIGs that are used for vacuum containing unfriendly gases.