KR20110097073A - Cooler - Google Patents

Abstract

The cryogenic freezer according to the present invention can be easily assembled concentrically with the frame and the cooling unit and brazed together because the cold finger brazes the inside of the frame and the cooling unit and then grinds the inner circumferential surface of the cold finger. Since the part is provided with a groove into which the brazing material may be separately inserted, the brazing material may be used in a large area, thereby improving adhesion and providing uniform adhesion.

Description

Cryogenic Freezers {COOLER}

The present invention relates to a cryogenic freezer that can be easily assembled to match the concentricity between the axially connected parts.

In general, the cryogenic freezer is a low vibration high reliability freezer used to cool small electronic parts or superconductors, and a working fluid such as helium or hydrogen generates a freezing output through a process of compression and expansion. Stirling refrigerators, GM refrigerators or Joule-Thomson refrigerators are widely known. These refrigerators have a problem in that their lubrication is deteriorated during high-speed operation as well as a separate lubrication for the wear of the friction portion during operation. Therefore, there is a need for a cryogenic freezer that maintains reliability even at high speeds and does not require long-term maintenance without additional lubrication. In recent years, a high-pressure working fluid acts as a kind of bearing to reduce friction between components. Lubricated cryogenic freezers are being applied.

The cryogenic refrigerator is pumped while compressing the refrigerant in a compression space, undergoes a heat dissipation and regeneration process, and then expands in the expansion space, and is configured to maintain the cryogenic temperature through heat exchange with the surroundings. At this time, a cold tubular cold finger forming the appearance of the regenerator is provided, and the cold finger is positioned between the frame and the cooling unit to be brazed and coaxially, and the cylinder, the displacer and the regenerator inside the frame and the cold finger. The parts are embedded.

However, in the conventional cryogenic freezer, thin tubular cold fingers are brazed on the inner circumferential surface of the frame and the cooling unit, respectively.Because the cold circumferential surface of the cold finger is crying due to the brazing, it is difficult to match the concentricity between the cold finger and the frame and the cooling unit. Since there is no concentricity with the parts embedded therein, there is a problem in that the assembly and operation reliability of the built-in parts.

In addition, since the cold finger is not only thin but also configured to maintain airtightness with other components, it is difficult to increase the adhesive force by using a large amount of brazing material, and it is difficult to provide a uniform adhesive force as a whole by brazing a larger area.

The present invention has been made to solve the above problems of the prior art, an object of the present invention is to provide a cryogenic freezer that can be easily assembled to center the cold finger to form the regenerator exterior with other components.

It is also an object of the present invention to provide a cryogenic freezer which can provide strong and uniform adhesion even if the cold finger forming the regenerator appearance is brazed with other components.

The cryogenic freezer according to the present invention for solving the above problems is a cylindrical cold finger to form a regenerator appearance; A frame in which an axial end of the cold finger is brazed to the inner circumferential surface; And, the other end in the axial direction of the cold finger brazing on the inner peripheral surface; including, characterized in that the inner peripheral surface of the cold finger combined with the frame and the cooling unit is ground operation.

In addition, in the present invention, the frame and the cooling unit is characterized in that a plurality of grooves are accommodated in the inner peripheral surface brazed with the cold finger.

In addition, in the present invention, the base which is the center of the heat dissipation unit coupled to the outer peripheral surface of one end of the frame in the axial direction; further comprising, the inner peripheral surface of the frame coupled to the base is characterized in that the grinding operation.

In addition, in the present invention, one end of the frame is coupled to the outer axial direction in the axial direction to fix the base in the axial direction of the frame; further comprising a frame, the inner peripheral surface coupled to the flange is characterized in that the grinding operation.

In addition, in the present invention, the cooling unit is characterized in that it is elastically supported in the axial direction during the grinding operation.

The cryogenic freezer according to the present invention configured as described above can be easily assembled concentrically with the frame and the cooling part because the cold finger is brazed inside the frame and the cooling part, and then the inner circumferential surface of the cold finger is grinded. In addition, it is possible to match concentrically with the components embedded in the cold finger and the frame, thereby improving the assemblability and ensuring the operational reliability of the internal components.

In addition, since the cryogenic freezer according to the present invention is provided with at least one groove in the inner circumferential surface of the frame or the cooling unit inner peripheral surface brazed with the cold finger, the brazing material is inserted into the groove of the frame and the groove of the cooling unit, and then the cold finger is inserted into the frame and the cooling unit. As the brazing in the state fitted inside, there is an advantage that can provide a uniform adhesive performance as well as improve the adhesive strength.

1 is a side view showing an example of a cryogenic freezer according to the present invention.
Figure 2 is a side cross-sectional perspective view showing an example of the cryogenic freezer according to the present invention.
Figure 3 is a side cross-sectional view showing an example of the cryogenic freezer according to the present invention.
Figure 4 is an exploded side cross-sectional view showing the brazed parts of the cryogenic freezer according to the present invention.
Figure 5 is a side cross-sectional view showing a part of the grinding process of the brazed parts of the cryogenic freezer according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 to 3 is a view showing an example of the cryogenic freezer according to the present invention.

One example of the cryogenic freezer according to the present invention is a case (10) to form an external appearance, as shown in Figures 1 to 3, the fixing member 20 is fixed in the case 10 to form a predetermined space, The movable member 30 is installed between the case 10 and the fixed member 20 to compress and expand the refrigerant while reciprocating linear movement in the compression space C in the fixed member 20 in the axial direction. A linear motor 40 driving the linear motor 40, a regenerator 50 coupled to the axial direction of the movable member 30, and a regenerator 50 which is equally regenerated between the refrigerant flowing in opposite directions. The radiating unit 60, which radiates heat of the refrigerant compressed and compressed around the movable member 30 and the regenerator 50 to the outside, is combined to form an expansion space E in the axial direction of the regenerator 50, and expands. The refrigerant is made up of a cooling unit 70 for absorbing external heat.

The case 10 includes a frame concentric with the regenerator 50, the heat dissipation unit 60, and the cooling unit 70, and a cylindrical shell tube fixed to the axial direction of the frame 11. tube: 12). The portion of the frame 11 to which the fixing member 20 is bolted is formed to have a thicker thickness than the shell tube 12 even though the diameter is smaller than that of the shell tube 12. To increase the thickness is formed thinner. The shell tube 12 is provided with a predetermined tube 13, and the inside of the case 10 maintains a vacuum state close to 100%, and then injects a refrigerant such as genuine He gas to form a vacuum state. In order to bleed air or to inject a refrigerant 13 is provided. In addition, the shell tube 12 is provided with a power supply terminal 14 for supplying power supplied to the linear motor 40.

The fixing member 20 is fixed to the frame 11 and extends from the cylinder 21 to the inside of the shell tube 12 and the displacer housing extending from the cylinder 21 to engage the inside of the frame 11. displacer housing (22). The cylinder 21 and the displacer housing 22 are formed in a stepped cylindrical shape. The diameter of the displacer housing 22 is smaller than that of the cylinder 21, and the connecting portion is extended on the outer circumferential surface of the cylinder 21. This frame 11 is bolted. At this time, the cylinder 21 and the displacer housing 22 form a compression space C in which the refrigerant is compressed. The through holes 21h and 22h communicate with the inside of the heat dissipation unit 60, respectively.

The movable member 30 includes a piston 31 reciprocating linearly in the cylinder 21 and a displacer 32 reciprocating linearly in conjunction with the piston 31 in the displacer housing 22. It includes. The piston 31 includes a piston body 311 provided with a gap on the inner circumferential surface of the cylinder 21, and a piston plug 312 provided inside the piston body 311. The displacer 32 includes a displacer rod 321 which is pierced through the center of the piston plug 312 and is bufferably supported by the leaf spring S fixed to the case 10, and the displacer housing ( It is composed of a displacer cover (322) to form a predetermined space in which the refrigerant flows by being accommodated / coupled to the displacer body (321a), which is an end of the displacer rod 321 embedded in the 22). A compression space C is formed between the piston 31 and the displacer body 321a. At this time, the displacer body 321a is formed with a U-shaped cross section and is provided with first and second through holes 321h and 321H communicating with the inside of the heat dissipation unit 60. In addition to the displacer valve 323 opened and closed by a pressure difference, a suction hole (not shown) communicating with the regenerator 50 is provided with a through hole 322H communicating with the inside of the displacer body 321a.

On the other hand, since the movable member 30 is a reciprocating linear motion, in addition to the leaf spring (S), a gas bearing capable of lubricating the components friction with each other is applied, it can be configured as follows. A plurality of storage grooves formed in the circumferential direction along the outer circumferential surface of the piston plug 312 to communicate with the flow path 312a provided in the axial direction of the piston plug 312 so that the refrigerant in the compression space (C) ( 312b is provided, and a plurality of radially penetrating the piston body 311 to supply the refrigerant stored in the storage groove 312b of the piston plug 312 into the space between the piston body 311 and the cylinder 21 The hole 311h is provided and radially of the piston plug 312 to supply the refrigerant stored in the storage groove 312b of the piston plug 312 into the space between the piston plug 312 and the displacer rod 321. A plurality of through holes 312h are provided. Of course, in order to guide the refrigerant stored in the storage groove 312b of the piston plug 312 to the hole 311h of the piston body 311 or the hole 312h of the piston plug 312, the outer peripheral surface of the piston plug 312 Various types of grooves (not shown) are provided in the circumferential direction or the axial direction.

The linear motor 40 includes a cylindrical inner stator 41 fixed to the outer circumferential surface of the cylinder 21, and a cylindrical outer stator fixed to the inner circumferential surface of the shell tube 12 so as to maintain a constant distance outside the inner stator 41. an outer stator 42 and a permanent magnet 43 connected to the piston body 311 so as to maintain a gap between the inner stator 41 and the outer stator 42. Of course, the outer stator 42 has a plurality of core blocks 412 mounted on the coil winding 411, and the coil winding 411 is connected to the power supply terminal 14 on the case 10 side. .

The regenerator 50 includes a cylindrical regeneration housing 51 coupled to the displacer housing 321a, a heat storage material 52 inserted into a portion of the displacer housing 321a and the regeneration housing 51, and a regeneration housing. (51) It consists of an end cap (53) attached to cover the end part, and is comprised so that a refrigerant | coolant can pass through the heat storage material 52 and the end cap 53. As shown in FIG. The heat storage material 52 receives and accumulates and returns energy during heat exchange with the refrigerant gas, and thus, the heat storage material 52 has a large heat exchange area and specific heat, a small thermal conductivity coefficient, and is preferably made of a material having uniform breathability. For example, it may be configured in a form in which fine threads are aggregated.

The heat dissipation unit 60 is composed of a cylindrical base 61 and a plate-like fin 62 arranged densely in the circumferential direction thereof, and is formed of a metal material such as copper having high heat transfer efficiency.

The cooling unit 70 is mounted at the end of the regenerator 50 to form an expansion space E between the end cap 53 and maintains the cryogenic temperature through a heat exchange action. Of course, the cooling unit 70 may be configured to form a larger surface area for heat exchange between the refrigerant inside and the outside air.

In addition, reference numeral 80, which is not shown, denotes a passive balancer, which reduces vibrations generated during operation of the cryogenic freezer.

Looking at the operation of the cryogenic freezer configured as described above, as follows.

First, when a current is supplied to the outer stator 42 through the power supply terminal 14, mutual electromagnetic force is generated between the inner stator 41, the outer stator 42, and the permanent magnet 43, and the permanent force is generated by the electromagnetic force. The magnet 43 is reciprocated linearly. At this time, since the permanent magnet 43 is connected to the piston body 311 and the piston plug 312 engaged therewith, the piston 31 moves reciprocally linearly with the permanent magnet 43. Therefore, when the piston 31 reciprocates linearly in the cylinder 21, the displacer 32 moves in the opposite direction to the movement of the piston 31 by the inertial force and is elastically supported by the leaf spring S. .

Accordingly, the refrigerant is compressed in the compression space C inside the cylinder 21 by the reciprocating linear motion of the piston 31 and the displacer 32 and passes through the through hole 21h of the cylinder 21 to form the frame 12. Pass through the inside is subjected to an isothermal compression process that is radiated by the heat dissipation unit (60). Thereafter, the refrigerant having undergone isothermal compression flows into the regenerator 50 through the through hole 22h of the displacer housing 22 and the first through hole 321h of the displacer body 321a, and flows in opposite directions. It undergoes an equal recovery process while exchanging heat with the refrigerant. Thereafter, the refrigerant having undergone the isotropic regeneration process exits and expands into the expansion space E and undergoes an isothermal expansion process in which the cooling unit 70 cools the outside air. Thereafter, the refrigerant having undergone the isothermal expansion process is introduced again into the regenerator 50 and then subjected to the isotropic regeneration process that is regenerated by the refrigerant flowing in the opposite direction as described above. At this time, after passing through the displacer body 321a and the displacer cover 322 through the inlet port and the displacer valve 323 provided in the displacer cover 322, the refrigerant may pass through the through hole of the displacer cover 322 ( 322H and the second through hole 321H of the displacer body 321a are introduced into the compression space C again. Of course, while the linear motor 40 is operated, the above isothermal compression process, isotropic regeneration process, isothermal expansion process, and isotropic regeneration process are repeated in sequence, and the cryogenic cooling is performed in the cooling unit 70.

Figure 4 is an exploded side cross-sectional view showing the brazed parts of the cryogenic freezer according to the present invention, Figure 5 is a side cross-sectional view showing a part of the grinding process of the brazed parts of the cryogenic freezer according to the present invention.

In the cryogenic apparatus according to the present invention, as shown in FIGS. 4 to 5, the cold fingers 54 forming the appearance of the regenerator 50 (shown in FIG. 3) are brazed inside the frame 11 and the cooling unit 70. Next, the inner circumferential surface of the cold finger 54 is ground to achieve concentricity.

As described above, the frame 11 is bolted to the inside of the cylinder 21 (shown in FIG. 3), and the base 61 included in the heat dissipation unit 60 (shown in FIG. 3) has a flange 63 on the outer circumferential surface thereof. Is fixed by. At this time, one end of the cold finger 54 is brazed in the frame 61, the inner peripheral surface of the frame 11 is provided with a ring-shaped groove 11h along the circumferential direction so that the brazing material can be fitted, the frame More than two grooves 11h of 11 may be formed at regular intervals in the axial direction.

The base 61 is formed in a cylindrical shape made of copper to increase the heat dissipation effect, and a portion of the frame 11 on which the base 61 is mounted is also formed to be relatively thin in order to increase the heat dissipation effect.

The flange 63 is fixed to the frame 11 to prevent the base 61 from being removed in the axial direction of the frame 11. At this time, the base 61 is brazed to the outer circumferential surface of the base 61 in a state of supporting the axial direction, the ring-shaped groove 63h along the circumferential direction so that the brazing material can be similarly fitted to the inner circumferential surface of the flange 63. Is provided, two or more grooves 63h of the flange 63 may be formed at regular intervals in the axial direction.

The cold finger 54 forms the appearance of the regenerator 50 (shown in FIG. 3), which is formed in a thin tubular shape in which a regenerator composed of the regeneration housing, heat storage material, and end cap described above can be accommodated. Of course, since the cold fingers 54 are thinly formed, both ends of the cold fingers 54, that is, the parts braided with the frame 11 and the cooling unit 70, cry, but the grinding operation of the inner circumferential surface of the cold fingers 54 is performed. Because of this, the inner circumferential surface of the cold finger 54 can be easily unfolded in the original state, and the concentricity with the parts engaged with each other can be matched.

The other end of the cold finger 54 is brazed, and the cooling unit 70 is provided with a ring-shaped groove 70h along the circumferential direction so that the brazing material can be fitted on the inner circumferential surface of the cooling unit 70. Two or more grooves 70h of the portion 70 may be formed at regular intervals in the axial direction.

Looking at the assembly process of the above components, as follows.

First, the base 61 is inserted into the outer circumferential surface of the frame 11, the brazing material is inserted into the groove 63h of the flange 63, and then the flange 63 is fitted into the outer circumferential surface of the frame 11. When heat is applied between the frame 11 and the flange 63 in the state of supporting axially, the base 61 is also fixed while the frame 11 and the flange 63 are brazed while the brazing material is melted.

Next, the brazing material is inserted into the groove 70h of the cooling unit 70, and then between one of the cold fingers 54 and the cooling unit 70 with one end of the cold finger 54 inserted into the inner circumferential surface of the cooling unit 70. When heat is applied, the cold finger 54 and the cooling unit 70 are uniformly fixed while the brazing material is melted.

Next, the brazing material is inserted into the groove 11h of the frame 11 on which the base 61 and the flange 63 are mounted, and then the other end of the cold finger 54 is inserted into the inner peripheral surface of the frame 11. When heat is applied between 11) and the cold finger 54, the frame 11 and the cold finger 54 are brazed while melting the brazing material.

As such, when the frame 11, the base 61, the flange 63, the cold finger 54, and the cooling unit 70 are assembled, the cooling unit 70 of the assembly is axially oriented to the grinding jig J. After elastic support, the inner peripheral surface of the engaging portion of the parts is ground. At this time, the base 61 grinds the inner circumferential surface portion of the frame 11 mounted on the outer circumferential surface, the flange 63 grinds the inner circumferential surface portion of the frame 11 mounted on the outer circumferential surface, and then the frame 11 and the cooling unit 70. ) Is grinding the entire inner circumferential surface of the cold finger 54 mounted on the outer circumferential surface. Accordingly, the frame 11, the cold finger 54 and the cooling unit 70 can be easily coaxially aligned, and the cylinders, displacers and regenerators mounted therein can also be coaxially assembled. Not only can the performance be improved, but also the operating reliability can be increased.

In the above, the present invention has been described in detail by way of examples based on the embodiments of the present invention and the accompanying drawings. However, the scope of the present invention is not limited by the above embodiments and drawings, and the scope of the present invention will be limited only by the contents described in the claims below.

Claims (5)

A cylindrical cold finger forming the regenerator appearance;
A frame in which an axial end of the cold finger is brazed to the inner circumferential surface; And,
And a cooling unit in which the other axial end of the cold finger is brazed on the inner circumferential surface thereof.
Cryogenic freezer, characterized in that the inner peripheral surface of the cold finger combined with the frame and the cooling unit is ground. The method of claim 1,
Cryogenic freezer, characterized in that the frame and the cooling portion is provided with a plurality of grooves for receiving the brazing material on the inner peripheral surface brazing the cold finger. The method of claim 1,
It further comprises a base, which is the center of the heat radiating portion coupled to the outer peripheral surface of the frame in the axial direction;
Cryogenic freezer, characterized in that the inner surface of the frame coupled to the base is ground. The method of claim 3,
A flange coupled to an outer circumferential surface of one end of the frame in an axial direction to fix the base in the axial direction of the frame;
Cryogenic freezer, characterized in that the inner peripheral surface of the flange coupled to the grinding work. The method according to any one of claims 1 to 4,
Cryogenic freezer characterized in that the cooling portion is elastically supported in the axial direction during the grinding operation.

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