CN103808990B - There is the capacitive probe device reducing electric field distortion function - Google Patents
There is the capacitive probe device reducing electric field distortion function Download PDFInfo
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- CN103808990B CN103808990B CN201410079496.6A CN201410079496A CN103808990B CN 103808990 B CN103808990 B CN 103808990B CN 201410079496 A CN201410079496 A CN 201410079496A CN 103808990 B CN103808990 B CN 103808990B
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- electric field
- ring
- inductance loop
- probe device
- vacuum cavity
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Abstract
The invention provides a kind of capacitive probe device having and reducing electric field distortion function.This capacitive probe device includes: vacuum cavity structure, in tubular；Insulating ceramics cylinder, is fixed on the inner side of vacuum cavity structure；Electronics note inductance loop, in the form of a ring, is prepared by conductive metal material, is fixed on the middle part inside insulating ceramics cylinder；Electric field improves ring, in the form of a ring, prepares conductive metal material, is fixed on the upper and lower inside insulating ceramics cylinder, and this electric field improves ring and electronics note inductance loop insulation, with vacuum cavity structure isoelectric level；And lead-in wire adapter assembly, for being drawn outside vacuum cavity structure by the induced signal of electronics note inductance loop.Capacitive probe device of the present invention adds the electric field of the metal material being insulated from and improves ring in the both sides of electronics note inductance loop, thus greatly reduces electronics note inductance loop both sides of the edge electric field distortion, makes electric field evenly.
Description
Technical field
The present invention relates to vacuum electronics technical field, measure the capacitive probe structure of electronics note speed system, especially relate to
And a kind of have reduce electric field distortion function capacitive probe device.
Background technology
Electron tube be a class in vacuum or gas medium, utilize electronics note and high-frequency electromagnetic field interactions and reality
Existing microwave power amplifies the active electronic device with translation function.Nowadays, electron tube radar, electronic countermeasure, guidance and
The fields such as satellite communication are widely used.Along with the development of electron tube technology, various electronics note is measured
System is arisen at the historic moment.
Fig. 1 is prior art capacitive probe device and the structural representation of associated components.As it is shown in figure 1, capacitive probe
Ring flange 200 and Devices to test are passed through in front end, such as electron gun, klystron, gyrotron etc., are connected, and are made pottery by insulation in its rear end
Porcelain 300 and connecting tube 400 are connected with plane blank flange 500.This capacitive probe 100 includes: vacuum cavity structure 110, and it is same
Shi Zuowei external electrode；Electronics note inductance loop 130, it is as interior electrode.Wherein, this vacuum cavity structure 110 and electronics note sensing
Having insulating ceramics cylinder 120 between ring 130, both constitute electric capacity, and electronics note inductance loop 130 connects the most pure virginity by wire 151
Outside cavity body structure 110.Capacitive probe is utilized to measure induced voltage V (t) of electronics note, and on plane blank flange 500
Measure beam current I (t), and then just can be calculated average axial velocity v (t) of electronics note by following formula:
V (t)=k I (t)/V (t) (1)
Wherein, this induced voltage V (t) be electronics note by vacuum cavity in capacitive probe electrode sensing obtain；k
It is the structure by capacitive probe and a constant coefficient of measuring circuit decision.
But, during realizing the present invention, it is found by the applicant that there is following technology in prior art capacitive probe device
Defect:
(1) having certain thickness due to electronics note inductance loop and insulating ceramics, therefore before and after inductance loop, edge just has
Bigger non-radial electric field, this adds increased the distortion of voltage waveform measured on electronics note inductance loop, make result of detection and
Subsequent calculations all brings bigger error；
(2) individually drawing from posterior edges due to the lead-in wire of electronics note inductance loop, this exacerbates electric field distortion, simultaneously
Lead-in wire is easily subject to the bombardment of stray electron, reduces the accuracy of probe detection；
(3) be positioned on vacuum cavity vacuum insulation feed head be conventional ceramic electrode, its outer lead joint be exposed
Space, it is easily subject to the interference of the various electromagnetic wave in space, even makes signal flood.
Summary of the invention
(1) to solve the technical problem that
In view of above-mentioned technical problem, the invention provides a kind of capacitive probe device having and reducing electric field distortion function,
To reduce the induction field distortion of electronics note inductance loop, improve the certainty of measurement of electronics note axial velocity.
(2) technical scheme
The present invention has the capacitive probe device of reduction electric field distortion function and includes: vacuum cavity structure 110, in tubular；
Insulating ceramics cylinder 120, is fixed on the inner side of vacuum cavity structure 110；Electronics note inductance loop 130, in the form of a ring, by metallic conduction material
Material preparation, is fixed on the middle part inside insulating ceramics cylinder 120；At least one electric field improves ring, in the form of a ring, by conductive metal material system
Standby, it is fixed on the top inside insulating ceramics cylinder 200 or bottom, this electric field improves ring and electronics note inductance loop 300 and insulate, and very
Cavity body structure 110 isoelectric level；And lead-in wire adapter assembly 150, for being drawn by the induced signal of electronics note inductance loop 130
Outside vacuum cavity structure 110.
(3) beneficial effect
From technique scheme it can be seen that the present invention have reduce electric field distortion function capacitive probe device have with
Lower beneficial effect:
(1) both sides at electronics note inductance loop add the electric field of the metal material being insulated from and improve ring, thus significantly
Decrease electronics note inductance loop both sides of the edge electric field distortion, make electric field evenly；
(2) vacuum insulation feed head passes from vacuum cavity outer wall and insulating ceramics cylinder, and soldering is in electronics note sensing
The outer middle side part of ring, thus do not interfere with the Electric Field Distribution of electronic induction ring, avoid lead-in wire by miscellaneous in vacuum cavity simultaneously
Dissipate the bombardment of electronics；
(3) in probe lead adapter assembly, the periphery of vacuum insulation feed head has outer electro-magnetic shielding cover, meanwhile, very
An empty insulation feed external coaxial shielding plug, makes probe adapter assembly have good anti-spatial electromagnetic wave interference ability, it is ensured that
The accuracy of the induced voltage of probe detection and the good anti-interference of transmitting procedure, make certainty of measurement be greatly improved.
Accompanying drawing explanation
Fig. 1 is prior art capacitive probe device and the structural representation of associated components；
Fig. 2 is the structural representation according to the embodiment of the present invention with the capacitive probe device reducing electric field distortion function.
[main element]
100-capacitive probe device；
110-vacuum cavity structure；120-insulating ceramics cylinder；
130-electronics note inductance loop；Before 141-, electric field improves ring；
After 142-, electric field improves ring；150-goes between adapter assembly；
151-vacuum insulation feed head；The outer electro-magnetic shielding cover of 152-；
153-coaxial shielding plug；
200-ring flange；
300-insulating ceramics；
400-connecting tube；
500-plane blank flange.
Detailed description of the invention
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and reference
Accompanying drawing, the present invention is described in more detail.It should be noted that in accompanying drawing or description describe, similar or identical portion
Divide and all use identical figure number.The implementation not illustrated in accompanying drawing or describe, for those of ordinary skill in art
Known form.Although it addition, can provide herein the demonstration of the parameter comprising particular value, it is to be understood that parameter is without definite etc.
In corresponding value, but can be similar to be worth accordingly in acceptable error margin or design constraint.Embodiment is mentioned
Direction term, such as " on ", D score, "front", "rear", "left", "right" etc., be only the direction with reference to accompanying drawing.Therefore, the side of use
It is used to illustrate not for limiting the scope of the invention to term.
The present invention has in the capacitive probe device reducing electric field distortion function, reduction electronics note sensing of adopting various measures
The electric field distortion of ring, it is therefore intended that ensure the accuracy that electronics note axial velocity is measured.
In one exemplary embodiment of the present invention, it is provided that a kind of have the capacitive probe reducing electric field distortion function
Device.Fig. 2 is the structural representation of the capacitive probe device according to the embodiment of the present invention with small electric field distortion function.Please join
According to Fig. 2, this capacitive probe device 100 includes: vacuum cavity structure 110, and in tubular, it is simultaneously as external electrode；Insulating ceramics
Cylinder 120, is fixed on the inner side of vacuum cavity structure 110；Electronics note inductance loop 130, in the form of a ring, is prepared by conductive metal material,
It is fixed on the middle part inside insulating ceramics cylinder 120；Front electric field improves ring 141 and rear electric field improves ring 142, in the form of a ring, by metal
Prepared by conductive material, be fixed on the upper and lower inside insulating ceramics cylinder 200, and both insulate with electronics note inductance loop 300,
Both are electrically connected to vacuum cavity structure 110, and with its isoelectric level；Lead-in wire adapter assembly 150, for being sensed by electronics note
The induced signal of ring is drawn outside vacuum cavity structure 110.
Each ingredient to the present embodiment below with the capacitive probe device reducing electric field distortion function is carried out in detail
Describe in detail bright.
Refer to Fig. 2, the front end of vacuum cavity structure 110 is connected to Devices to test by ring flange 200, as electron gun,
Klystron, gyrotron etc., its rear end is connected to plane blank flange 500 by insulating ceramics 300 and connecting tube 400.Wherein, should
Vacuum cavity structure 110 earthing potential.
Vacuum cavity structure 110, ring flange 200, connecting tube 400 and plane blank flange 500 are by non-magnetic rustproof steel
Material preparation.Insulating ceramics 300 vacuum leakproofness can be prepared by good alumina ceramic material.
In the inner side of vacuum cavity structure 110, soldering fixed insulation ceramic cylinder 120.The size of this insulating ceramics cylinder 120 by
The external diameter of the internal diameter of vacuum cavity structure 110 and electronics note inductance loop 130 is determined, it equally can be good by vacuum leakproofness
Aluminium oxide ceramics is made.In the inner side of this insulating ceramics cylinder 120, it is machined with three groove-like structure, is respectively used to place above-mentioned
Front electric field improves ring 141, electronics note inductance loop 130 and rear electric field and improves ring 142.
It should be noted that this insulating ceramics cylinder 120 can be one-body molded preparation, it is also possible to be by various piece respectively
Assembling after molding, this is not limited by the present invention.
In three groove-like structure inside insulating ceramics cylinder 120, respectively soldering be fixed with front electric field improve ring 141, electricity
Son note inductance loop 130 and rear electric field improve ring 142.Wherein, electronics note inductance loop 130 is made up of oxygenless copper material, and its ring wall is thick
Spending the thinnest and visibly homogeneous, inwall is through polishing, and fineness is the highest.Electronics note inductance loop 130 and vacuum cavity structure are divided
Not as the inner and outer electrodes of the present embodiment capacitive probe device.
In the present embodiment, front electric field improves ring 141 and rear electric field improves ring 142 and prepared by oxygenless copper material, in annulus
Shape, its internal diameter is identical with the internal diameter of electronics note inductance loop 130.Further, this front electric field improves ring 141 and rear electric field improves ring 142
Note inductance loop 130 electric insulation with electronics, and be connected in vacuum cavity structure 110, with its isoelectric level.Further, electric field changes
Axial distance L between kind ring and electronics note inductance loop meets: 0.2mm≤L≤2mm.Preferably, L=0.5mm.
In the capacitive probe structure of prior art, in centre position, its electric field is more satisfactory electricity to electronics note inductance loop
, and in its edge, axial electric field will be produced.And in the present embodiment, due to above electronics note inductance loop 130
Adding front electric field with lower section and improve ring 141 and rear electric field improves ring 142, the two electric field improves ring, changes in electronics note sense
The Electric Field Distribution of Ying Huan 130 edge, reduces the non-radial electric field of edge, thus it is abnormal to greatly reduce both sides of the edge electric field
Become, make the electric field of electronics note inductance loop 130 evenly.
Outside the signal sensed in order to electronics is noted inductance loop 130 draws vacuum cavity structure 110, the present embodiment capacitive is visited
Needle device also includes the adapter assembly 150 that goes between.Refer to Fig. 2, this lead-in wire adapter assembly 150 includes:
Vacuum insulation feed 151, is installed in vacuum cavity structure 110, and its inner wire passes vacuum cavity structure 110
With insulating ceramics cylinder 120, it is brazed in the outside in the middle part of electronics note inductance loop 130；
Outer electro-magnetic shielding cover 152, be fixed in vacuum cavity structure 110 and with ground good contact, be shielded from vacuum insulation
Feed head (151) stretches out the periphery of described vacuum cavity structure (110) part, wherein, vacuum insulation feed 151 and vacuum chamber
Body structure 110, electro-magnetic shielding cover 152 insulate, with external pelivimetry circuit signal line good contact, this vacuum insulation feed 151 He
Outer electro-magnetic shielding cover 152 forms a structure being similar to BNC connector；
Coaxial shielding plug 153, its inside conductor is connected to the inner wire of vacuum insulation feed 151, its screen layer and ground
Good contact, the induced signal obtained for electronics is noted inductance loop 130 causes the test test equipment in the external world.
In the capacitive probe device of prior art, by wire exposed inside vacuum cavity structure 110, electronics is noted
The signal of inductance loop 130 is drawn, and so, the existence of wire has increased the weight of the distortion of electronics note inductance loop electric field, and this wire passes
The accuracy of defeated signal can not be protected.And in the present embodiment, the inner wire of vacuum insulation feed 151 is brazed in
Middle part outside electronics note inductance loop 130, had not both interfered with electronics note inductance loop Electric Field Distribution, will not be by vacuum cavity yet
The bombardment of stray electron, is so substantially improved the induction voltage waveform of oxygen-free copper inductance loop detection electronics note.
Additionally, in the present embodiment, arrange dispatch from foreign news agency in vacuum insulation feed 151 part stretching out vacuum cavity structure 110
Magnetic shielding cover 152, use coaxial shielding plug 153 to transmit signal simultaneously, outer electro-magnetic shielding cover 152, coaxial shielding plug 153
Screen layer good contact is to ground, thus avoids to greatest extent and done by external electromagnetic ripple by electronics note inductance loop signal
Disturb, there is good anti-spatial electromagnetic wave interference ability, it is ensured that the accuracy of the induced voltage of probe detection, make electronics note axially
The detection accuracy of velocity measuring system is greatly improved.
So far, already in connection with accompanying drawing, the present embodiment has been described in detail.According to above description, those skilled in the art
The present invention should be had and reduce the capacitive probe device of electric field distortion function and had and clearly recognize.
Additionally, the above-mentioned definition to each element and method is not limited in various concrete structures, the shape mentioned in embodiment
Shape or mode, it can be changed or replace, such as by those of ordinary skill in the art simply:
(1) in addition to non-magnetic rustproof Steel material, vacuum cavity structure 110 can also use other metal materials, such as anaerobic
Prepared by copper product.And in addition to alumina material, insulating ceramics cylinder 120 can also be with other insulant such as politef
Prepared by material；
(2) described coaxial shielding plug, except BNC connector structure, it is also possible to for the coaxial fitting structure of other forms, example
As: N connector；
(3) in addition to brazing mode, electric field improves ring and can also be fixed in other ways on insulating ceramics cylinder, such as:
Laser Welding.
In sum, the invention provides a kind of capacitive probe device having and reducing electric field distortion function, be substantially improved
The induction voltage waveform of detection, and shield the spatial electromagnetic that probe lead wire post is subject to and disturb, make the electronics note sense detected
Answer voltage accuracy to be greatly enhanced, there is extremely strong application value.
Particular embodiments described above, has been carried out the purpose of the present invention, technical scheme and beneficial effect the most in detail
Describe in detail bright, be it should be understood that the specific embodiment that the foregoing is only the present invention, be not limited to the present invention, all
Within the spirit and principles in the present invention, any modification, equivalent substitution and improvement etc. done, should be included in the guarantor of the present invention
Within the scope of protecting.
Claims (8)
1. one kind has the capacitive probe device reducing electric field distortion function, it is characterised in that including:
Vacuum cavity structure (110), in tubular；
Insulating ceramics cylinder (120), is fixed on the inner side of vacuum cavity structure (110)；
Electronics note inductance loop (130), in the form of a ring, is prepared by conductive metal material, is fixed on described insulating ceramics cylinder (120) inner side
Middle part；
Front electric field improves ring (141) and rear electric field improves ring (142), the most in the form of a ring, prepares conductive metal material, fixes respectively
In the upper and lower of described insulating ceramics cylinder (200) inner side, these two electric fields improve ring and described electronics note inductance loop (130)
Insulation, with described vacuum cavity structure (110) isoelectric level；And
Lead-in wire adapter assembly (150), for being drawn described vacuum cavity by the induced signal of described electronics note inductance loop (130)
Structure (110) outward, including:
Vacuum insulation feed head (151), is installed on described vacuum cavity structure (110), and its inner wire passes described vacuum chamber
Body structure (110) and insulating ceramics cylinder (120), be brazed in the outside at described electronics note inductance loop (130) middle part；And
Outer electro-magnetic shielding cover (152), be fixed on described vacuum cavity structure (110) upper and with ground good contact, be shielded from vacuum
The periphery of described vacuum cavity structure (110) part is stretched out in insulation feed head (151).
Capacitive probe device the most according to claim 1, it is characterised in that described electric field improves ring by oxygenless copper material system
Standby, its internal diameter is identical with the internal diameter of described electronics note inductance loop (130).
Capacitive probe device the most according to claim 1, it is characterised in that described electric field improves ring and the note sense of described electronics
Axial distance L between Ying Huan meets: 0.2mm≤L≤2mm.
Capacitive probe device the most according to claim 3, it is characterised in that described L=0.5mm.
Capacitive probe device the most according to claim 1, it is characterised in that in the inner side of described insulating ceramics cylinder (120)
Having three groove-like structure, described front electric field improves ring (141), electronics note inductance loop (130) and rear electric field and improves ring (142) point
It is not placed in these three groove-like structure.
Capacitive probe device the most according to claim 5, it is characterised in that described front electric field improves ring (141), electronics note
Inductance loop (130) and rear electric field improve in three groove-like structure that ring (142) is brazed in described insulating ceramics cylinder (120) respectively.
Capacitive probe device the most according to claim 1, it is characterised in that described lead-in wire adapter assembly also includes:
Coaxial shielding plug (153), its inside conductor is connected to the inner wire of described vacuum insulation feed head (151), its screen layer
With ground good contact, the induced signal obtained for described electronics is noted inductance loop (130) causes the test equipment in the external world.
Capacitive probe device the most according to any one of claim 1 to 7, it is characterised in that described vacuum cavity structure
(110) being prepared by non-magnetic rustproof Steel material, described insulating ceramics cylinder (120) is prepared by alumina ceramic material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410079496.6A CN103808990B (en) | 2014-03-06 | 2014-03-06 | There is the capacitive probe device reducing electric field distortion function |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410079496.6A CN103808990B (en) | 2014-03-06 | 2014-03-06 | There is the capacitive probe device reducing electric field distortion function |
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| CN103808990A CN103808990A (en) | 2014-05-21 |
| CN103808990B true CN103808990B (en) | 2016-09-21 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1394042A (en) * | 1972-05-31 | 1975-05-14 | Varian Associates | Electron collector having means for reducing secondary electron interference in a linear beam microwave tube |
| CN101752168A (en) * | 2008-12-03 | 2010-06-23 | 中国科学院电子学研究所 | Double-layer electrode for multi-level depressed collector and preparation process thereof |
| CN101800145A (en) * | 2010-04-20 | 2010-08-11 | 安徽华东光电技术研究所 | Collecting electrode used for traveling wave tube and manufacture method thereof |
| KR101156569B1 (en) * | 2010-12-09 | 2012-06-20 | 국방과학연구소 | Muti donut type wideband small e-field probe for analyzing target iemi |
-
2014
- 2014-03-06 CN CN201410079496.6A patent/CN103808990B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1394042A (en) * | 1972-05-31 | 1975-05-14 | Varian Associates | Electron collector having means for reducing secondary electron interference in a linear beam microwave tube |
| CN101752168A (en) * | 2008-12-03 | 2010-06-23 | 中国科学院电子学研究所 | Double-layer electrode for multi-level depressed collector and preparation process thereof |
| CN101800145A (en) * | 2010-04-20 | 2010-08-11 | 安徽华东光电技术研究所 | Collecting electrode used for traveling wave tube and manufacture method thereof |
| KR101156569B1 (en) * | 2010-12-09 | 2012-06-20 | 국방과학연구소 | Muti donut type wideband small e-field probe for analyzing target iemi |
Non-Patent Citations (1)
| Title |
|---|
| 基于容性感应探针的强流电子注轴向速度测量系统的研究;姜波等;《真空科学与技术学报》;20111130;第31卷(第6期);第729页第2栏至第730页第1栏，图3 * |
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