KR20010083619A - Flexure bearing support structure for lubricationless pulse tube refrigerator - Google Patents

Abstract

PURPOSE: Supporting structure of flexure bearings of a lubricationless pulse tube refrigerator is provided to prevent error in a process of assembling flexure bearings by keeping the exact radial fixing state between a piston and a cylinder and to enhance the performance of a refrigerator by reducing the abrasion between the piston and the cylinder efficiently. CONSTITUTION: Plural flexure bearings(15) are inserted to the upper and the lower end of a drive shaft in a casing. The flexure bearings are connected to a support member(13) in the casing by bolts(B), having plural leaf springs of spiral type for inducing the resonance motion and the rectilinear motion of a piston. Plural fitting holes(17,17a) are formed on the support member. To connect the flexure bearings to the support member in the casing, plural assembling pins(16) are inserted into the fitting holes of the support member. The bolts are fitted to each connecting hole(18a) of the support member. Then, the assembling pins are removed. The flexure bearings are fixed in the exact radial direction between the piston and a cylinder. Thereby, the flexure bearings are assembled easily. The fitting holes are formed between the connecting holes(18,18a) without symmetry to shorten the assembling time. In addition, the fitting holes are formed smaller than the connecting holes to prevent error in the assembling process.

Description

FLEXURE BEARING SUPPORT STRUCTURE FOR LUBRICATIONLESS PULSE TUBE REFRIGERATOR}

The present invention relates to a flexure bearing support structure of a non-lubricated pulsating tube freezer, and more particularly, to a flexure bearing inducing a resonant and straight movement of a piston in an lubricating pulsating tube freezer with an exact radius between the piston and the cylinder. Easily assembled to maintain a solid state of orientation.

In general, a cryogenic freezer for cooling small electronic components and superconductors is mainly used a thermal regeneration refrigerator such as a Stirling Refrigerator and a GM Refrigerator, and these refrigerators operate to increase their reliability. There is a search for a method of lowering the speed, removing the shape of the sealing material in which friction occurs, and removing the moving part.

On the other hand, the development of a highly reliable cryogenic freezer that does not require long-term maintenance is also required. One of such cryogenic freezers is a lubricationless pulse tube refrigerator.

On the open side of the tube, the pulsating tube freezer uses a principle that a large temperature gradient can be obtained when the pressure is changed by periodically injecting a gas having a constant temperature into one of the clogged tubes, when the flow of gas is small. It is a device that implements cryogenic refrigeration, and the pulsating tube freezer is a variation of a stirling freezer suitable for use as a freezer having a relatively low freezing capacity and requiring reliability because of a low average pressure and pressure ratio. Compared to having two moving parts such as standing, the moving part of the pulsating tube freezer is different from having only one separate compressor.

Figure 1 is a longitudinal sectional view showing a conventional pulsating tube refrigerator, Figure 2 is an exploded perspective view showing a state in which the flexure bearing of Figure 1 is fastened, the conventional pulsating tube refrigerator is a piston coupled to the mover of the linear motor separately It is possible to pump the working gas while linearly reciprocating the cylinder without lubricating action of the cylinder. The driving unit 10 generates a reciprocating motion of the working gas, and the pump is reciprocated in the tube while being pumped by the driving unit 10. It is largely divided into a refrigeration unit 30 having a cryogenic portion by a thermodynamic cycle of the working gas.

The drive unit 10 is coupled to the casing 11, the linear drive motor 20 mounted inside the casing 11, the cylinder 19 is provided on the upper end, and the drive motor 20 A drive shaft 12, a piston 14 connected to the drive shaft 12 and inserted into the cylinder 19, and a support member inserted into the upper and lower ends of the drive shaft 12, respectively, and inside the casing 11. The bolt B is fastened to each of the bolt fastening holes 18 and 18a at 13a, and a plurality of leaf springs formed in a spiral type are superposed to induce resonance and straight movement of the piston 14. It consists of a flexure bearing (15a) and the drive side sealing shell 21 which encloses the lower part of the said casing 11 so that it may be sealed.

The refrigeration unit (30) generates heat in the on-side heat exchanger (31a) in which compression and expansion occur at both ends as masses of working gas flow by the working gas pumped by the driving unit (10). On the other hand, in the cold side heat exchanger 31b in which expansion occurs, the mass flow and the pressure pulsation of the pulsating tube 31 absorbing external heat and the working gas reciprocated by being connected to the on-side heat exchanger 31a of the pulsating tube 31 are reciprocated. An orifice 32 for generating a phase difference and achieving thermal equilibrium, a storage container 33 connected to the orifice 32 to temporarily hold a working gas, and a pumped operation to the pulsating tube 31 A regenerator 34 for compensating the temperature of the working gas that stores heat of the gas and returns from the pulsation tube 31 to the drive unit 10, and the cylinder 19 of the regenerator 34 and the drive unit 10. Between It consists of a precooler (35) for first cooling the high and high pressure working gas connected and pumped, and a freezing side sealing shell (36) surrounding the pulsation tube (31) and regenerator (34).

Accordingly, as power is applied to the drive motor 20, the drive shaft 12 reciprocates in a straight line, and the piston 14 integrally coupled to the drive shaft 12 is linear in the cylinder 19. By operating the reciprocating motion to pump the operating gas of the refrigeration unit 30 to form the cryogenic portion on the cold side heat exchanger (31b) side of the pulsation tube (31).

On the other hand, in the case of employing the non-lubricating method in such a conventional pulsating tube refrigerator, the space between the piston 14 and the cylinder 19 is adopted to adopt a clearance seal between the piston 14 and the cylinder 19. The flexure bearing 15a, which can maintain a rigid state in the radial direction, is inserted into the upper and lower ends of the drive shaft 13 to be fastened with a bolt B to the support member 13a inside the casing 11. In this case, when the above-mentioned flexure bearing 15a in which a plurality of leaf springs are overlapped is fastened, a plurality of leaf springs do not fit in the correct position, and as a result, the clearance seal is broken, and thus the piston 14 and There are many problems, such as a lot of wear occurs between the cylinders 19 to cause a decrease in the performance of the refrigerator.

Accordingly, the present invention is to solve the above-mentioned problems, the flexure bearing for inducing the resonant motion and the straight motion of the piston in the non-lubricated pulsating tube freezer to maintain a precise radial rigid state between the piston and the cylinder It can be easily assembled to prevent the occurrence of defects during the assembly of the flexure bearing, and to effectively reduce the wear between the piston and the cylinder due to the correct assembly of the flexure bearing, thereby improving the performance of the refrigerator. It is an object of the present invention to provide a flexure bearing support structure of a non-lubricated pulsating tube refrigerator.

Figure 1 is a longitudinal cross-sectional view showing a conventional pulsating tube refrigerator.

Figure 2 is an exploded perspective view showing a state in which the flexure bearing of Figure 1 is fastened

Figure 3 is an exploded perspective view showing a state in which the flexure bearing according to the invention is fastened

Explanation of symbols on the main parts of the drawings

10; Drive unit 11; Casing

12; Drive shaft 13; Support member

14; Piston 15; Flexure bearing

16; Assembly pins 17,17a; Assembly pin insertion hole

18,18a; Bolt fastener B; volt

In order to achieve the above object, the present invention is connected to the drive shaft constituting the drive unit is a flexure bearing overlapping a plurality of leaf springs formed in a spiral type to induce the resonant motion and the straight motion of the piston inserted into the cylinder And an assembly pin insertion hole formed in the casing of the drive unit to fix the assembly pin by inserting the assembly pin when the flexure bearing is fastened to the support member and to remove the assembly when the assembly is completed. A flexure bearing support structure of a lubricating pulsating tube refrigerator is provided.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention for achieving the above object will be described in detail.

Figure 3 is an exploded perspective view showing a state in which the flexure bearing according to the present invention is fastened, and the same reference numerals are given to the same parts as in the prior art to explain the present invention.

The present invention is inserted into the upper and lower ends of the drive shaft 12 inside the casing 11 constituting the drive unit 10 of the non-lubricated pulsating tube refrigerator, respectively. And a flexure bearing 15 to the flexure bearing 15 and the support member 13 in which a plurality of leaf springs formed in a spiral type overlap each other to induce resonance and straight movement of the piston 14. The assembly pin insertion hole 17, 17a for inserting and fixing the assembly pin 16 when fastening to the support member 13 and removing when the fastening is completed is formed.

In addition, the assembly pin insertion holes 17 and 17a are angles other than 180 ° symmetry between the plurality of bolt fastening holes 18 and 18a respectively formed in the flexure bearing 15 and the support member 13. The size of the assembly pin insertion hole 17, 17a is formed to be smaller than the size of the bolt fastening holes (18) (18a) to be different from the bolt fastening holes (18) (18a).

1 and 3, the present invention configured as described above is inserted into upper and lower ends of the drive shaft 12 inside the casing 11 constituting the drive unit 10 of the non-lubricated pulsating tube refrigerator. The flexure bearing 15 is fastened by a bolt B to the support piece 13 inside the casing 11 and overlaps a plurality of leaf springs formed in a spiral type to induce resonance and straight movement of the piston 14. In order to fasten the flexure bearing 15 to the support member 13 inside the casing 11 in a state where the assembly pin insertion holes 17 and 17a are formed in the support member 13 and the support member 13, The assembly pin 16 passes through the assembly pin insertion hole 17 of the flexure bearing 15 and is inserted into the assembly pin insertion hole 17a of the support member 13 to fix the assembly pin 16.

Then, the bolt B is passed through the bolt fastening hole 18 formed in the flexure bearing 15 and finally fastened to the bolt fastening hole 18a formed in the support member 13 to complete the fastening operation. By removing the pin 16, the assembly work can be easily completed so that the flexure bearing 15 is maintained in a precise radial direction between the piston 14 and the cylinder 19.

In addition, a plurality of bolt fastenings are formed in the flexure bearing 15 and the support member 13 to the assembly pin insertion holes 17 and 17a formed in the flexure bearing 15 and the support member 13, respectively. Since the ball 18 and 18a are formed at an angle other than 180 °, the ease of assembly and the assembly time can be shortened, and the size of the assembly pin insertion holes 17 and 17a may be reduced by a bolt fastening hole 18. Since it is formed smaller than the size of the (18a) it is possible to prevent the assembly failure that may occur during assembly by differentiating the bolt fastening holes (18) (18a).

As described above, the present invention can be easily assembled so that the flexure bearing for inducing the resonant motion and the straight motion of the piston in the non-lubricated pulsating tube refrigerator can be maintained so as to maintain the exact radial rigid state between the piston and the cylinder. It is possible to eliminate the phenomenon that defects occur when assembling the flexure bearing, and it is possible to effectively reduce the abrasion between the piston and the cylinder by the correct assembly of the flexure bearing, thereby improving the performance of the refrigerator. Is a very useful invention.

Although the preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-described embodiments, and is generally defined in the technical field to which the present invention pertains without departing from the gist of the present invention as claimed in the following claims. Anyone with knowledge of the world will be able to make various changes.

Claims (3)

Connected to the drive shaft constituting the drive unit, a plurality of leaf springs formed in a spiral type are formed inside the casing of the drive unit and the casing of the drive unit to induce the resonant motion and the straight motion of the piston inserted into the cylinder. Flexure of the lubrication-free pulsating tube freezer, characterized in that the assembly pin is inserted into the support member for supporting the lexer bearing, the assembly pin is inserted to fix the assembly pin when the fastener bearing is fastened to the support member, Bearing support structure. The flexure of the lubrication-free pulsating tube refrigerator according to claim 1, wherein the assembly pin insertion hole is formed at an angle other than 180 ° symmetry between the flexure bearing and the plurality of bolt fastening holes respectively formed in the support member. Bearing support structure. The flexure bearing support structure of claim 1, wherein the size of the assembly pin insertion hole is smaller than that of the bolt fastening hole so as to be differentiated from the bolt fastening hole.