CN101349593B - Infrared detector dewar component high vacuum holding structure and implementing method thereof - Google Patents
Infrared detector dewar component high vacuum holding structure and implementing method thereof Download PDFInfo
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- CN101349593B CN101349593B CN2008100424287A CN200810042428A CN101349593B CN 101349593 B CN101349593 B CN 101349593B CN 2008100424287 A CN2008100424287 A CN 2008100424287A CN 200810042428 A CN200810042428 A CN 200810042428A CN 101349593 B CN101349593 B CN 101349593B
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Abstract
The invention discloses a structure of the infrared detector Dewar assembly high vacuum holding for the spaceflight and an implementation process thereof, which is applied to the space application technology of an infrared detector Dewar assembly. The structure of the infrared detector Dewar assembly high vacuum holding for the spaceflight is formed by a high airtight vacuum self-locking valve, a connecting tube, a high airtight vacuum butt joint, an exhaust pipe and an infrared detector Dewar assembly. The invention obtains the structure of the infrared detector Dewar assembly high vacuum holding for the spaceflight through introducing special processing methods on the sealing structure and the connection of the high airtight vacuum self-locking valve and the high airtight vacuum butt joint, can facilitate the infrared detector Dewar assembly to obtain limitless vacuum service life, and has not strict requirements to the technique procedures for reducing gas efficiency in the preparation and encapsulation technique of an infrared detector, thereby greatly reducing the preparation and encapsulation costs of the infrared detector Dewar assembly.
Description
Technical field
The present invention relates to the infrared detector dewar component technology, specifically refer to structure and implementation method that a kind of infrared detector dewar component high vacuum keeps.
Background technology
Infrared detector module has a wide range of applications in the infrared field of space flight.Along with the raising of wavelength to long wave expansion and detection sensitivity, infrared burnt detector must could be worked under profound hypothermia.Because advantages such as mechanical refrigeration have compact conformation, volume is little, in light weight, refrigerating capacity is big, cooling time is short, the cryogenic temperature controlled range is big, such detector adopts the mechanical refrigeration mode mostly in use in the space at present.So also make and adopt the Dewar encapsulation to form infrared detector dewar assembly when it is used mostly.Vacuum life is a Dewar component important techniques index, that is to say in the Dewar to keep certain vacuum tightness.Because the intrinsic deflation characteristic of material, As time goes on, vacuum tightness can constantly descend in the Dewar.When vacuum tightness drops to a certain degree, the residual gas convection heat transfer causes the Dewar component heat load sharply to increase, after heat load is increased to a certain degree, when the cold that mechanical refrigerator provides can't satisfy requiring of detector profound hypothermia work, infrared eye just can't be operated in necessary temperature spot, and the residual gas in the Dewar can condense in detector surface, makes the performance degradation even the forfeiture of detector, thereby makes the paralysis of high spatial resolution infrared remote sensing instrument.
The characteristics occasion that infrared detector dewar assembly is used at space industry, the report that its vacuum is kept disposal route seldom both at home and abroad.And the factor of vacuum retention time that influences infrared detector dewar assembly main following some: 1) the parts material of infrared detector dewar assembly and degassing processing technology; 2) end vacuum of infrared detector dewar assembly exhaust, baking temperature and evacuation time; 3) adsorbent is installed in the infrared detector dewar assembly.Preceding 2 depend primarily on infrared eye and Dewar prepares level, simultaneously also relevant with level of processing with employed raw-material production.And the method that the installation adsorbent prolongs the vacuum retention time, application to the space flight instrument of infrared detector dewar assembly can bring following problem: 1) need irregular logical big current activation in the process of using, this just requires to be provided with in the IR sensor device system large-current electric source circuit and vacuum judgment means, increases the complexity and the total power consumption of system; 2) adsorbance of adsorbent is always limited, and the interior vacuum tightness of Dewar can descend behind the certain hour, can cause the load of refrigeration machine to increase, and this just makes provides power supply total power consumption of refrigeration machine to increase, and causes the efficient reduction of refrigeration machine simultaneously.
Summary of the invention
The purpose of this invention is to provide structure and implementation method that a kind of infrared detector dewar component high vacuum keeps, solve the problem of the long vacuum life of infrared detector dewar component.
The structure that infrared detector dewar component high vacuum of the present invention keeps as shown in Figure 1, it mainly comprises: high airtight vacuum latching valve 1, connecting pipe 2, high airtight vacuum open joint 3, gas outlet 4, infrared detector dewar assembly 5.Connecting pipe 2 and gas outlet 4 are the oxygen-free copper copper pipes through vacuum annealing, link by the air intake opening seat 101 of vacuum brazing technique connecting pipe 2 with high airtight vacuum latching valve 1, gas outlet 4 links with infrared detector dewar assembly 5, and connecting pipe 2 and gas outlet 4 link together by the airtight vacuum open joint 3 of height infrared detector dewar assembly 5 and high airtight vacuum latching valve 1 are communicated.
High airtight vacuum latching valve 1 is a kind of position high airtight vacuum solenoid that can keep by the moment power-on switch, and it mainly is made up of the permanent magnet 107 of permanent magnet 104, moving mass 105, the coil 106 of the maintenance toroidal of air intake opening seat 101, spool 102, O-ring seal 103, off status, toroidal that the state of opening keeps.Air intake opening seat 101, spool 102 are made by stainless steel material, and moving mass 105 adopts soft iron material, and the permanent magnet 104,107 of toroidal adopts ndfeb magnets, and O-ring seal 103 adopts fluororubber to make.
High airtight vacuum latching valve 1 has increased position holding device on original solenoid valve work principle, position holding device is made up of the permanent magnet 107 of the permanent magnet 104 of toroidal, moving mass 105, toroidal, the permanent magnet 104 by toroidal or 106 and moving mass 105 between magnetic field suction realize that the position keeps.The off status shown in the accompanying drawing 2 and the state of opening are by the electric current of coil 105 logical different directions is realized switching.Concrete principle of work following (seeing accompanying drawing 2): 1) the polarity of the magnetic field opposite of the permanent magnet 106 of the permanent magnet 104 of toroidal and toroidal is identical; 2) O-ring seal 103 adopts fluororubber, and the smooth and bright and clean high impermeability that obtains is wanted in corresponding seal interface; When 3) 106 moments, logical forward dc was electric to coil, coil 106 made moving mass 105 produce the magnetic polarity magnetic fields, and the magnetic pole of magnetic pole that moving mass 105 produces previously and the permanent magnet of toroidal 104 is different in nature and the generation attractive force.Simultaneously permanent magnet 106 magnetic poles of the magnetic pole that produces later of moving mass 105 and toroidal are the same sexes and produce repulsive force.Two power additions make moving mass 105 move to off status shown in accompanying drawing 2 (a); 4) similarly, give coil logical reverse direct current of 106 moments, moving mass 105 just moves to the state of opening shown in accompanying drawing 2 (b); 5) after coil 106 outages, the magnetic polarity of moving mass 105 disappears, but because the permanent magnet 104 of toroidal or 106 magnetic field suction, moving mass 105 can keep original position.
High airtight vacuum open joint 3 as shown in Figure 3, it by 301,2 tapers of 2 hexagonal (hexagon)nuts after before 302,2 tapers of cutting ferrule cutting ferrule 303 and a fittings body 304 form, whole joint is all made with stainless steel material.High airtight vacuum open joint 3 is as follows with the seal connecting method of gas outlet 4 and connecting pipe 2: the intermediate case of nut 301 shells and fittings body 304 is made hexagon, by external thread relative rotary motion on internal thread on the nut 301 and the fittings body 304, thereby cutting ferrule 303 travels forward before allowing back cutting ferrule 302 promote, and obtains hermetically-sealed construction I and II because preceding cutting ferrule 303 and connecting pipe 2 or gas outlet 4 local pressures are out of shape.
Implementation method of the present invention is as follows:
1) by the vacuum brazing technique sintering connecting pipe 2 is arranged in advance on the air intake opening seat 101 with the airtight vacuum latching valve 1 of height earlier, then O-ring seal 103 corresponding sealing surfaces are carried out mechanical lapping and polishing, guarantee that the seal interface will smoothly and bright and clean obtain high impermeability;
2) finish the assemblings such as permanent magnet 107 of the toroidal that permanent magnet 104, moving mass 105, the coil 106 of the maintenance toroidal of air intake opening seat 101, spool 102, O-ring seal 103, off status, the state of opening keep by the assemble sequence of each part of the airtight vacuum latching valve 1 of height, each tie point in the technology adopts airtight welding;
3) in the infrared detector dewar assembly preparation process, earlier gas outlet 4 is sintered on the shell of infrared detector dewar assembly 5 by vacuum brazing after, finish the preparation of infrared detector dewar assembly 5 again;
The other end of the connecting pipe 2 that 4) will be installed together with the airtight vacuum latching valve 1 of height is successively on fit on nut 301, back cutting ferrule 302, preceding cutting ferrule 303 and the fittings body 304, utilize two spanners clamping nut 301 and relative rotation of fittings body 304 middle hexagonal housings respectively, finish the connection of high airtight vacuum open joint 3 and high airtight vacuum latching valve 1 by above-mentioned seal connecting method;
5) will be and infrared detector dewar assembly 5 gas outlet 4 together, realized the connection of high airtight vacuum open joint 3 and infrared detector dewar assembly 5 by similar step 4;
6) when infrared eye Dewar component 5 uses on ground, earlier the high airtight vacuum latching valve 1 in the structure of the present invention is carried out high vacuum exhaustion one time by certain frock, coil 106 inverse current of logical moment to the airtight vacuum latching valve 1 of height before the exhaust is opened by it, fully closing for again the coil forward current of logical moment of high airtight vacuum latching valve 1 by it after the exhaust, utilize position holding device to guarantee the vacuum state that infrared detector dewar assembly Dewar cavity is interior;
7) after infrared eye Dewar component 5 carries out space with the infrared remote sensing instrument, open for the coil inverse current of logical moment of high airtight vacuum latching valve 1 by it, and the state that utilizes position holding device to allow high airtight vacuum latching valve 1 be in out all the time, utilize the vacuum environment in the space that infrared detector dewar assembly is carried out constantly exhaust stably, make in the Dewar cavity of infrared detector dewar assembly to be in very high vacuum state forever, thereby realize the vacuum life of infrared detector dewar component endless.
The present invention has following advantage to be:
(1) of the present invention simple in structure, easy to use, large-current electric source circuit and vacuum judgment means have been avoided being provided with in the infrared remote sensing instrument system, the complexity of simplified system and total power consumption, increase the reliability of system, made infrared detector dewar assembly obtain the vacuum life of endless simultaneously again;
(2) the present invention is not strict with the process procedure that reduces gas efficiency in infrared eye preparation and the encapsulation, greatly reduces the packaging cost of infrared detector dewar assembly.；
(3) the moment power-on switch of the airtight vacuum latching valve of height of the present invention has overcome the shortcoming that the traditional electrical magnet valve must the medium-term and long-term galvanization of holding coil just can be held open state;
(4) position of the switch of the airtight vacuum latching valve of height of the present invention keeps having overcome the traditional electrical magnet valve for being held open long-term energising consumed power, and the shortcoming of easy scaling loss at high temperature;
(5) sealing of the airtight vacuum open joint of height of the present invention can obtain being better than 1 * 10-12 torr. the impermeability of liter/second, and simple in structure and highly reliable;
(6) the airtight vacuum open joint of height of the present invention has realized that effectively the height of infrared detector dewar assembly and high airtight vacuum latching valve is tightly connected, make the preparation of infrared detector dewar assembly and high airtight vacuum latching valve to carry out separately, technology is not intersected, and has simplified technology.
Description of drawings
The structural representation that Fig. 1 infrared detector dewar component high vacuum keeps;
Among the figure: the high airtight vacuum latching valve 1 of 1-;
101-air intake opening seat;
The 102-spool;
The 103-O-ring seal;
The permanent magnet of the maintenance toroidal of 104-off status;
The 105-moving mass;
The 106-coil;
107-opens the permanent magnet of the toroidal of state maintenance;
The 2-connecting pipe;
The high airtight vacuum open joint of 3-;
The 301-nut;
Cutting ferrule behind the 302-;
Cutting ferrule before the 303-;
The 304-fittings body;
The 4-gas outlet;
The 5-infrared detector dewar assembly.
The off status of the high airtight vacuum latching valve 1 of Fig. 2 (a) and (b) and open the status architecture enlarged diagram.
The stressed front and back of high airtight vacuum open joint 3 hermetically-sealed constructions of Fig. 3 (a) and (b) enlarged diagram.
Embodiment
Below in conjunction with accompanying drawing the specific embodiment of the present invention is described in further detail:
Embodiment is that certain space flight project keeps structure with the infrared detector dewar assembly high vacuum, and as shown in Figure 1, its main implementation method is as follows:
1, the preparation of high airtight vacuum latching valve:
1) selection of each parts material is as follows: its air intake opening seat 101, spool 102 etc. are selected stainless steel for use; , moving mass 105 is selected soft iron for use; O-ring seal 103 is selected fluororubber for use; The permanent magnet 107 of the toroidal that the permanent magnet 104 of the maintenance toroidal of off status and the state of opening keep is selected ndfeb magnet for use;
2) the self-sustaining design in position is mainly the permanent magnet determining dimensions, and permanent magnet 104 or permanent magnet 107 require to identify maximum centrifugal force sum in the level mechanical test condition much larger than the deadweight and the product of moving mass 105 with the attractive force of moving mass 105.According to approximate formula F=3.9962 * 10
-3* Br
2* C * S
1/2Calculate that (F is an attractive force in the formula, unit: newton; To ndfeb magnet Br is 12.5, unit: do gram; C is a thickness, unit: millimeter; S is an area, and unit is: square millimeter; ) again according to the requirement of structural design, determine that permanent magnet is of a size of: external diameter φ 20mm, internal diameter φ 8mm, thickness 4mm;
3) electrical parameter of coil determine behind the requirement coil electricity be moving mass 105 be subjected to permanent magnet 104 and permanent magnet 107 make a concerted effort identify the centrifugal force maximum in the level mechanical test condition and the resistance three power sums of hermetically-sealed construction much larger than the deadweight and the product of moving mass 105.According to the requirement of structural design, determine that the electrical parameter that line is advised is again: operating voltage DC28V, resistance are 17.8 Ω, pulsewidth 200ms, interval 1s;
2, the preparation of high airtight vacuum open joint, connecting pipe and gas outlet: high airtight vacuum open joint adopts the import stainless steel, carries out Precision Machining by designing requirement; Connecting pipe and gas outlet are selected the oxygen-free copper copper pipe for use, carry out vacuum annealing before the connection.
3, structure connection of the present invention and operation steps are as follows:
A) by the vacuum brazing technique sintering connecting pipe 2 is arranged in advance on the air intake opening seat 101 with the airtight vacuum latching valve 1 of height earlier, then O-ring seal 103 corresponding sealing surfaces are carried out mechanical lapping and polishing, guarantee that the seal interface will smoothly and bright and clean obtain high impermeability;
B) finish the assemblings such as permanent magnet 107 of the toroidal that permanent magnet 104, moving mass 105, the coil 106 of the maintenance toroidal of air intake opening seat 101, spool 102, O-ring seal 103, off status, the state of opening keep by the assemble sequence of each part of the airtight vacuum latching valve 1 of height, each tie point in the technology adopts laser bonding to connect, and hunts leak by highly sensitive leak locator and to guarantee the whole leak rate of high airtight vacuum latching valve;
C) in the infrared detector dewar assembly preparation process, earlier gas outlet 4 is sintered on the shell of infrared detector dewar assembly 5 by vacuum brazing after, finish the preparation of infrared detector dewar assembly 5;
The other end of the connecting pipe 2 that d) will be installed together with the airtight vacuum latching valve 1 of height is successively on fit on nut 301, back cutting ferrule 302, preceding cutting ferrule 303 and the fittings body 304, utilize two spanners respectively in the middle of clamping nut 301 and the fittings body 304 the hexagonal housings apply relative rotation of power of 7.5N, by external thread relative rotary motion on internal thread on the nut 301 and the fittings body 304, thereby cutting ferrule 303 travels forward before allowing back cutting ferrule 302 promote, and obtains hermetically-sealed construction I and II because preceding cutting ferrule 303 and connecting pipe 2 local pressures are out of shape.So just realized that high airtight vacuum open joint 3 docks installation with the vacuum of high airtight vacuum latching valve 1;
E) will be with the other end of infrared detector dewar assembly 5 gas outlet 4 together fit on nut 301 successively, back cutting ferrule 302, preceding cutting ferrule 303 and fittings body 304 on, utilize two spanners clamping nut 301 and relative rotation of fittings body 304 middle hexagonal housings respectively, by external thread relative rotary motion on internal thread on the nut 301 and the fittings body 304, thereby cutting ferrule 303 travels forward before allowing back cutting ferrule 302 promote, and obtains hermetically-sealed construction I and II because preceding cutting ferrule 303 and gas outlet 4 local pressures are out of shape.So just realized that high airtight vacuum open joint 3 docks installation with the vacuum of infrared detector dewar assembly 5;
F) when infrared eye Dewar component 5 uses on ground, earlier it is carried out the airtight vacuum latching valve 1 of height of the present invention and carry out high vacuum exhaustion one time by certain frock, before the exhaust coil 106 logical 28V, the 1.6A of the airtight vacuum latching valve 1 of height, 2 seconds moment inverse current are opened by it, fully closing for again coil 106 logical 28V, the 1.6A of high airtight vacuum latching valve 1,2 seconds moment forward current by it after the exhaust, utilize position holding device to guarantee the vacuum state that infrared detector dewar assembly Dewar cavity is interior;
G) after infrared eye Dewar component 5 carries out space with the infrared remote sensing instrument, open for coil 106 logical 28V, the 1.6A of high airtight vacuum latching valve 1,2 seconds inverse current by it, and the state that utilizes position holding device to allow high airtight vacuum latching valve 1 be in out all the time, utilize the vacuum environment in the space that infrared detector dewar assembly is carried out constantly exhaust stably, make in the Dewar cavity of infrared detector dewar assembly to be in very high vacuum state forever, thereby realize the vacuum life of infrared detector dewar component endless.
Below just finish structure assembling and realization that infrared detector dewar component high vacuum keeps, obtained the vacuum life of infrared detector dewar component endless.
Claims (4)
1. the structure that keeps of an infrared detector dewar component high vacuum, it is made up of the airtight vacuum latching valve of height (1), connecting pipe (2), high airtight vacuum open joint (3), gas outlet (4), infrared detector dewar assembly (5), it is characterized in that:
A. air intake opening seat (101) connecting pipe (2) that links and the gas outlet (4) that links by vacuum brazing technique and infrared detector dewar assembly (5) by vacuum brazing technique and high airtight vacuum latching valve (1) links together by high airtight vacuum open joint (3), and infrared detector dewar assembly (5) and high airtight vacuum latching valve (1) are communicated;
B. the position holding device that has second permanent magnet (107) of first permanent magnet (104), moving mass (105) and toroidal to form on the high airtight vacuum latching valve (1) by toroidal, wherein moving mass (105) adopts soft iron material;
C. high airtight vacuum open joint (3) is realized being tightly connected by preceding cutting ferrule (303) and connecting pipe (2), the distortion of gas outlet (4) local pressure.
2. the structure that a kind of infrared detector dewar component high vacuum according to claim 1 keeps is characterized in that: said connecting pipe (2) and gas outlet (4) adopt the oxygen-free copper copper pipe through vacuum annealing.
3. the structure that a kind of infrared detector dewar component high vacuum according to claim 1 keeps is characterized in that: first permanent magnet (104) of said toroidal, second permanent magnet (107) of toroidal adopt ndfeb magnet.
4. the structure that a kind of infrared detector dewar component high vacuum according to claim 1 keeps, it is characterized in that: each parts of the airtight vacuum open joint of said height (3) all adopt stainless steel material to make.
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| CN101349593B true CN101349593B (en) | 2010-06-02 |
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| CN102353456B (en) * | 2011-08-30 | 2013-08-14 | 中国科学院上海技术物理研究所 | Infrared detector Dewar component space on-track vacuum processing device and realization method thereof |
| CN104731126B (en) * | 2015-01-21 | 2016-11-30 | 中国科学院上海技术物理研究所 | A kind of temperature control method based on integrated form Dewar component temperature variation testing refrigeration structure |
| CN115388615B (en) * | 2022-04-19 | 2023-11-24 | 北京师范大学 | Argon liquefaction system |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1820885A (en) * | 2006-03-24 | 2006-08-23 | 中国科学院上海技术物理研究所 | Vacuum seal welding method for window and optic window of low temperature metal Dewar |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1820885A (en) * | 2006-03-24 | 2006-08-23 | 中国科学院上海技术物理研究所 | Vacuum seal welding method for window and optic window of low temperature metal Dewar |
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| JP特开2000-223755A 2000.08.11 |
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