中科微点-全球专利检索

  1. Login
  2. Sign Up

Search Results

25 records (took 0.022 seconds)

    X-ray tube target and X-ray tubes utilising such a target
    2.
    发明授权
    X-ray tube target and X-ray tubes utilising such a target 失效
    X射线管靶和X射线管

    公开(公告)号：US3890521A

    公开(公告)日：1975-06-17

    申请号：US31890472

    申请日：1972-12-27

    Applicant: THOMSON CSF

    Inventor： SHROFF ARVIND

    IPC: H01J35/10

    CPC classification number: H01J35/108 ,  H01J2235/084

    Abstract: The present invention relates to a graphite target for X-ray tubes. In order to avoid the drawbacks of graphite carrier (1) targets due to transformation into carbide of the photo-emissive coating (3) by the carrier material, the invention provides for the formation of the intermediate layer (2) in these targets, in the shape of two sub-layers one of which (20), in contact with the carrier, is made of a refractory material which does not form a carbide (iridium for example), and the other of which (21) is made of another refractory material (tantalum for example), which prevents diffusion of carbon from the carrier into the emissive layer.

    Abstract translation: 本发明涉及X射线管的石墨靶。 为了避免由载体材料转化为光致发射涂层（3）的碳化物而导致石墨载体（1）靶的缺点，本发明提供了在这些靶中形成中间层（2）， 其中一个（20）与载体接触的两个子层的形状由不形成碳化物（例如铱）的耐火材料制成，而另一个（21）由另一个 耐火材料（例如钽），其防止碳从载体扩散到发射层中。

    Directly heated cathode for high frequency electron tubes - using graphite substrate covered by inert metal, then tungsten impregnated with aluminate(s), followed by noble metal
    5.
    发明专利
    Directly heated cathode for high frequency electron tubes - using graphite substrate covered by inert metal, then tungsten impregnated with aluminate(s), followed by noble metal 未知

    公开(公告)号：FR2475796A1

    公开(公告)日：1981-08-14

    申请号：FR8003050

    申请日：1980-02-12

    Applicant: THOMSON CSF

    Inventor： SHROFF ARVIND

    IPC: H01J1/14 ,  H01J1/15 ,  H01J21/10

    Abstract: The cathode has a substrate (1) of pyrolytic graphite heated by electric resistance, and covered by an emitter layer (3) of sintered metal, which is impregnated with barium- and calcium- aluminate. Between substrate (1) and layer (3) is a thin film (2) of a material which does not react chemically with carbon; and layer (3) is covered by a layer (4) of a refractory metal with a high work function. Layer (2) is pref. Ir or Re; whereas the metal in layer (3) is pref. pure tungsten, or a mixt. of W plus a refractory metal with a high work function, esp. osmium. The cathode is used esp. in an electron tube for UHF or microwaves. This cathode will operate at the low temp. of 1000-1100 deg. C, as compared with 1400-1500 deg. C required for a cathode using an emitter of LaB6.

    THERMOELECTRONIC CATHODE
    6.
    发明专利
    THERMOELECTRONIC CATHODE 未知

    公开(公告)号：DE3173470D1

    公开(公告)日：1986-02-20

    申请号：DE3173470

    申请日：1981-10-27

    Applicant: THOMSON CSF

    Inventor： PALLUEL PIERRE ,  SHROFF ARVIND

    IPC: H01J23/06 ,  H01J1/28 ,  H01J23/04

    Abstract: This invention concerns a thermoelectronic cathode for hyperfrequency electron tubes. The cathode comprises a cylindrical molybdenum casing, the lower portion of which contains a heating filament, while the upper portion contains two superimposed porous bodies, the lower one made from impregnated material, and the upper one from non-impregnated material.

    8.
    发明专利
    未知

    公开(公告)号：FR2445605A1

    公开(公告)日：1980-07-25

    申请号：FR7836487

    申请日：1978-12-27

    Applicant: THOMSON CSF

    Inventor： CLERC GUY ,  SHROFF ARVIND

    IPC: H01J1/15 ,  H01J23/05 ,  H01J19/08

    Abstract: A direct heating thermionic emission cathode for high frequency tubes of the diode, tetrode or pentode type. It comprises a pyrolytic graphite support and a lanthanum hexaboride-based thermoemissive material, these elements being separated by a layer which constitutes a diffusion barrier and comprises a tantalum or hafnium carbide, a metal of the platinum group or a boron compound.

    10.
    发明专利
    未知

    公开(公告)号：FR2469792A1

    公开(公告)日：1981-05-22

    申请号：FR7927715

    申请日：1979-11-09

    Applicant: THOMSON CSF

    Inventor： SHROFF ARVIND ,  PALLUEL PIERRE

    IPC: H01J1/14 ,  H01J1/28 ,  H01J9/04 ,  H01J23/04 ,  H01J23/06 ,  H01J1/13

    Abstract: The hot cathode, according to the invention, is constituted by a fritted matrix 1 and a heating filament 4, said matrix being formed from a powder mixture 2 of tungsten and another high work function refractory metal and covered with a high work function refractory metal film 3. FIG. 3.

Patent Agency Ranking