CN112945465A

CN112945465A - Cesium clock stem is with vacuum leak hunting frock

Info

Publication number: CN112945465A
Application number: CN202011586716.6A
Authority: CN
Inventors: 王一非
Original assignee: Beijing Institute of Radio Metrology and Measurement
Current assignee: Beijing Institute of Radio Metrology and Measurement
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2021-06-11

Abstract

A vacuum leak detection tool for a cesium clock core column belongs to the technical field of vacuum detection auxiliary devices and comprises a detected core column assembly, a core column pressing block, a limiter and a leak detection cylinder; a stopper is inserted into the upper end face of the leakage detecting barrel, the upper end face of the stopper is in contact connection with the lower end face of the core column pressing block, and the core column pressing block is in bolted connection with the leakage detecting barrel; the core column to be detected is fixedly arranged on the base through vacuum brazing to form the core column assembly to be detected, the structure is simple, and the problems that the core column of a cesium clock is complex in shape and structure, many points are prone to leakage and leakage detection is very difficult are solved; meanwhile, the combination of the limiter and the vacuum sealing ring ensures that the high-precision vacuum leak detection is carried out on the through electrode, so that the high vacuum acquisition and maintenance of the physical part of the cesium atomic clock are effectively ensured, and the reliability and the service life of the cesium atomic clock are ensured.

Description

Cesium clock stem is with vacuum leak hunting frock

Technical Field

The invention belongs to the technical field of vacuum detection auxiliary devices, and particularly relates to a vacuum leak detection tool for a cesium clock core column.

Background

The atomic clock can provide accurate time frequency signals, is the most important key equipment in the field of time keeping and time service of various countries in the world at present, and currently, the more mature atomic clocks mainly comprise a rubidium clock, a hydrogen clock and a cesium clock. The cesium clock has the advantages of good long-term stability, high accuracy, good startup reproducibility and zero drift, and has irreplaceable important functions. The cesium clock core column has complex shape and structure, many leakage points and very difficult leakage detection.

Disclosure of Invention

(1) Technical problem to be solved

The embodiment of the invention provides a vacuum leak detection tool for a cesium clock core column, which solves the problems of complex shape and structure, multiple leakage points and difficulty in leak detection of the cesium clock core column through a detected core column assembly, a limiter, a core column pressing block and a leak detection cylinder.

(2) Technical scheme

The embodiment of the invention provides a vacuum leak detection tool for a cesium clock core column, which comprises a detected core column assembly, a core column pressing block, a limiter and a leak detection barrel, wherein the core column pressing block is arranged on the core column; a stopper is inserted into the upper end face of the leakage detecting barrel, the upper end face of the stopper is in contact connection with the lower end face of the core column pressing block, and the core column pressing block is in bolted connection with the leakage detecting barrel; wherein, the pipeline mouth has been seted up to leak hunting section of thick bamboo up end intermediate position, the slot has been seted up in the pipeline mouth outside, slot outside array is provided with the screw thread through-hole, it passes to be examined stem subassembly lower extreme the stopper stretches into in the pipeline mouth, just it passes in proper order to be examined stem subassembly upper end stopper, stem briquetting stretch into external space.

Furthermore, an opening which penetrates through the core column pressing block from top to bottom is formed in the middle of the lower end face of the core column pressing block, and through holes are formed in the outer side of the opening in an array mode.

Further, the through holes and the threaded through holes are in one-to-one correspondence, namely the central axis of one through hole is superposed with the central axis of one threaded through hole.

Furthermore, the inside cavity of stopper is provided with the cavity of inserting, the cavity of inserting is the echelonment circle.

Further, the inner diameter of the insertion cavity is of a structure with a large upper part and a small lower part.

Further, a vacuum sealing ring is arranged in the slot.

Further, the vacuum sealing ring is a fluororubber ring.

Further, the detected stem assembly comprises a base; and the base mounting surface is vacuum brazed with a feedthrough electrode assembly.

Further, a vacuum leak detector is fixedly arranged at the bottom of the leak detection cylinder.

(3) Advantageous effects

In conclusion, the core column to be detected is fixedly arranged on the base through vacuum brazing to form the core column assembly to be detected, the structure is simple, and the problems that the core column of a cesium clock is complex in shape and structure, many points are prone to leakage, and leakage detection is very difficult are solved; meanwhile, the combination of the limiter and the vacuum sealing ring ensures that the high-precision vacuum leak detection is carried out on the through electrode, so that the high vacuum acquisition and maintenance of the physical part of the cesium atomic clock are effectively ensured, and the reliability and the service life of the cesium atomic clock are ensured.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

fig. 2 is a schematic cross-sectional view of the stopper of the present invention.

In the figure: 1-a stem assembly under test; 2-core column pressing block; 3-a stopper; 4-a leak detection cylinder; 5-vacuum sealing ring.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the invention and are not intended to limit the scope of the invention, i.e., the invention is not limited to the embodiments described, but covers any modifications, alterations, and improvements in the parts, components, and connections without departing from the spirit of the invention.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

Fig. 1 is a schematic diagram of the overall structure of a vacuum leak detection tool for a cesium clock core column in an embodiment, and as shown in fig. 1, the vacuum leak detection tool comprises a core column pressing block 2, a stopper 3 and a leak detection barrel 4 which are sequentially arranged from top to bottom; the lower terminal surface of stem briquetting 2 touches and connects in the up end of stopper 3, stopper 3 cartridge in the up end of a leak hunting section of thick bamboo 4, just stem briquetting 2 with 4 bolted connection of leak hunting section of thick bamboo.

In this embodiment, the stopper 3 is provided with a hollow penetrating cavity, which is a stepped cylindrical cavity, as shown in fig. 2, secondly, a pipeline port is arranged in the middle of the upper end surface of the leakage detecting barrel 4, a slot is arranged outside the pipeline port, the vacuum sealing ring 5 is arranged in the slot, the vacuum sealing ring 5 and the limiter 3 are inserted in the slot, and the outer side of the slot is provided with threaded through holes in an array manner, and it is noted that the inner surface of the vacuum seal ring 5 is attached to the end wall of the slot close to the pipeline port, and the vacuum seal ring 5 adopts a standard size fluororubber ring with the outer diameter of 34mm and the wire diameter of 3.1mm, can perform high vacuum leak detection on a cesium clock stem column at the pressure of <1E-12 Pa.m 3/s, therefore, the vacuum maintaining level of the physical part of the cesium clock is effectively guaranteed, and the reliability and the service life of the cesium clock are improved.

In addition, in the present embodiment, the inspected stem assembly 1 includes a base; the base mounting surface is vacuum brazed with punching electrode groups, and the number of the punching electrode groups is nine; the base is accommodated in the inserting cavity, the lower end face of the base abuts against the upper end face of the vacuum sealing ring 5, accurate positioning is achieved through the limiting stopper 3, and the assembling precision requirement is guaranteed.

In this embodiment, the terminal surface intermediate position under the stem briquetting 2 sets up the opening that runs through from top to bottom for through the punching electrode, simultaneously, opening outside array is provided with the through-hole, with screw thread through-hole one-to-one, one promptly the axis of through-hole and one the axis coincidence of screw thread through-hole, wherein, will be examined stem subassembly 1 with stem briquetting 2 through bolted connection and push down, even terminal surface butt in vacuum seal 5 under the base, ensure to be examined the vacuum seal effect of stem subassembly 1.

In addition, the bottom of the leak detection barrel 4 is fixedly provided with a KF25 standard vacuum flange interface, so that vacuum connection with a vacuum leak detector is realized, and vacuum leak detection is conveniently carried out on a piercing electrode at the position 9 of the detected core column assembly 1.

In the description of the present invention, it is to be understood that the terms "central," "lateral," "upper," "lower," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the indicated orientations and positional relationships, based on the orientations and positional relationships illustrated in the drawings, to facilitate the description of the invention and to simplify the description, but do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified. Furthermore, the term "comprises" and any variations thereof is intended to cover non-exclusive inclusions.

The present invention has been described in terms of embodiments, and several variations and modifications can be made to the device without departing from the principles of the present invention. It should be noted that all the technical solutions obtained by means of equivalent substitution or equivalent transformation, etc., fall within the protection scope of the present invention.

Claims

1. The utility model provides a cesium clock stem is with vacuum leak hunting frock which characterized in that: the device comprises a detected core column assembly (1), a core column pressing block (2), a limiter (3) and a leakage detecting cylinder (4); a limiter (3) is inserted into the upper end face of the leakage detecting barrel (4), the upper end face of the limiter (3) is in contact connection with the lower end face of the core column pressing block (2), and the core column pressing block (2) is in bolt connection with the leakage detecting barrel (4); wherein, the pipeline mouth has been seted up to leak hunting section of thick bamboo (4) up end intermediate position, the slot has been seted up in the pipeline mouth outside, slot outside array is provided with the screw thread through-hole, it passes to be examined stem subassembly (1) lower extreme stopper (3) stretch into in the pipeline mouth, just it passes in proper order to be examined stem subassembly (1) upper end stopper (3), stem briquetting (2) stretch into external space.

2. The vacuum leak detection tool for the cesium clock stem as set forth in claim 1, wherein: an opening penetrating from top to bottom is formed in the middle of the lower end face of the core column pressing block (2), and through holes are formed in the outer side of the opening in an array mode.

3. The vacuum leak detection tool for the cesium clock stem as set forth in claim 2, wherein: the through holes correspond to the thread through holes one by one, namely the central axis of one through hole is superposed with the central axis of one thread through hole.

4. The vacuum leak detection tool for the cesium clock stem as set forth in claim 1, wherein: the hollow insertion cavity is arranged in the limiter (3) and is a stepped circle.

5. The vacuum leak detection tool for the cesium clock stem as set forth in claim 4, wherein: the inner diameter of the insertion cavity is of a structure with a large upper part and a small lower part.

6. The vacuum leak detection tool for the cesium clock stem as set forth in claim 1, wherein: the vacuum sealing ring (5) is arranged in the slot.

7. The vacuum leak detection tool for the cesium clock stem as set forth in claim 6, wherein: the vacuum sealing ring (5) is a fluororubber ring.

8. The vacuum leak detection tool for the cesium clock stem according to any one of claims 1 to 7, characterized in that: the detected core column assembly (1) comprises a base; and the base mounting surface is vacuum brazed with a feedthrough electrode assembly.

9. The vacuum leak detection tool for the cesium clock stem as set forth in claim 8, wherein: and a vacuum leak detector is fixedly arranged at the bottom of the leak detection barrel (4).