CN220750437U - Pneumatic Stirling refrigerator - Google Patents

Abstract

The utility model discloses a pneumatic Stirling refrigerator, comprising: the rotary compressor at least comprises a motor assembly, a compression piston assembly and a compression end cover, wherein a hollow hard tubular bulge is arranged on the outer side of the compression end cover; the pneumatic expander at least comprises a base, a piston assembly, a cold accumulator and a cold finger cylinder; the pneumatic expander is connected with the rotary compressor by welding through a hard tubular bulge on the compression end cover; the motor assembly is used for driving the compression piston to reciprocate, and pressure waves are generated and are led into the pneumatic expander through the hard tubular bulge, so that the expansion piston of the pneumatic expander reciprocates. The structure has the advantages of compact characteristics of the integral Stirling refrigerator and the pneumatic expander, and a spring structure is eliminated, so that the whole machine is more compact.

Description

Pneumatic Stirling refrigerator

Technical Field

The utility model relates to the field of refrigerators, in particular to a pneumatic Stirling refrigerator.

Background

In recent years, with the wide application of infrared technology in military fields such as infrared imaging, reconnaissance alarm, early warning monitoring, guidance, mid-high altitude remote air defense and the like, infrared focal plane detector technology has been rapidly developed. With the development of infrared technology, the Stirling refrigerator is used as an important component for cooling the infrared detector, can provide a low-temperature working environment for the infrared detector, reduces noise and improves the sensitivity of the device. The small-sized integral Stirling refrigerator adopts helium as a working medium, can generally provide a cold head temperature of 50K ∈180K, and provides a required working environment for the refrigeration type infrared detector.

Stirling refrigerators can be generally divided into two main types, split and monolithic. Wherein, the integral structure is more complex, and the assembly requirement is more strict. Due to the influences of the volume and the installation datum plane, the integral refrigerator cannot meet the installation requirement in certain occasions, and the vibration of the compressor generated by the integral Stirling refrigerator can be transmitted to the cold end through the refrigerator part, so that the mounting surface of the cold end chip is dithered, and the imaging effect of the detector is further influenced. The existing split Stirling refrigerator has the problems of large volume, heavy weight, high power consumption and the like, and limits the application of the infrared detector assembly.

Disclosure of Invention

In order to solve the technical problems, the utility model provides a pneumatic Stirling refrigerator.

According to some embodiments of the utility model there is provided a pneumatic stirling cooler comprising: the rotary compressor comprises a motor assembly, a compression piston assembly and a compression end cover; the pneumatic expander comprises an expansion piston assembly, a cold accumulator assembly and a cold finger cylinder; wherein the motor assembly is used for driving the compression piston to reciprocate and enabling the expansion piston of the pneumatic expansion machine to reciprocate through pressure waves generated by the compression piston.

Compared with the prior art, the utility model has the advantages that: by arranging the compression gland and the hollow hard tubular bulge positioned outside the compression gland, the expansion end and the compression end are combined into a whole through welding, so that a separate pipe is eliminated, and the machine has the compact characteristic of an integral Stirling refrigerator and the characteristic that the pneumatic expander can randomly adjust the cold finger installation angle. In addition, the structure makes the pneumatic expander not need to be provided with springs, so that not only is the complex expansion spring installation process eliminated, but also the axial length of the expander is reduced, and the whole machine is more compact.

Drawings

FIG. 1 is a schematic diagram of some embodiments of the pneumatic Stirling cooler of the present utility model.

Fig. 2 is a schematic diagram of a rotary compressor in some embodiments of the pneumatic stirling cooler of the present utility model.

Fig. 3 is a schematic diagram of the configuration of a pneumatic expander in some embodiments of the pneumatic stirling cooler of the present utility model.

Fig. 4 is a schematic diagram of the configuration of an expansion piston in some embodiments of the pneumatic stirling cooler of the present utility model.

Fig. 5 a-5 c are schematic illustrations of the connection of a pneumatic expander to a rotary compressor of some embodiments of the pneumatic stirling cooler of the present utility model.

Fig. 6 is a schematic view of the compression end cap of some embodiments of the pneumatic stirling cooler of the present utility model.

Detailed Description

The technical solutions in the embodiments of the present utility model will be clearly and completely described in the following with reference to the drawings in the embodiments of the present utility model, so that the advantages and features of the present utility model can be more easily understood by those skilled in the art, and thus the protection scope of the present utility model is more clearly and clearly defined. It should be apparent that the described embodiments of the utility model are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The inventor has proposed a pneumatic Stirling refrigerator with split hose in the chinese patent application number CN202123419828.5 before, however, the split hose structure adopted by the inventor needs to weld two ends of the split hose with the expansion base and the compression end cover respectively, so that the direction of the cold finger is not easy to control, and because the spring is arranged at the tail of the expansion piston of the pneumatic expander, the installation complexity is increased, the split structure is not compact enough, and the occupied space is large. Based on this, the inventor further research and experiments, and proposes the scheme of the application.

Referring to fig. 1, there is provided a pneumatic stirling cooler 100 according to an embodiment of the present utility model, comprising: the rotary compressor 120 at least comprises a motor assembly, a compression piston assembly and a compression end cover, wherein a hollow hard tubular bulge is arranged on the outer side of the compression end cover; the pneumatic expander 140 at least comprises a base, a piston assembly, a regenerator and a cold finger cylinder; the pneumatic expander 140 is welded to the rotary compressor 120 by a hard tubular boss on the compression end cover, and the rotary compressor 120 compresses the gas and introduces the compressed gas into the pneumatic expander through the hard tubular boss.

Further, the pneumatic expander 140 may be welded around the rigid tubular protrusion according to set angle requirements, such that the cold finger angle of the pneumatic expander 140 can be set or adjusted according to specified requirements.

This application has novel through adopting above-mentioned structure, has relieved the restriction at 90 between compression piston and the expansion piston in the integral rotatory Stirling refrigerator, through set up stereoplasm tubular bulge on the compression end cover, makes pneumatic expander can be through this stereoplasm tubular bulge, carries out the welding between expansion end and the compression end according to required settlement angle for the expansion end can be through gaseous power to the phase angle between expansion piston and the compression piston adjust.

In addition, the gas is led into the expansion base of the pneumatic expander through the hollow hard tubular bulge, so that the communication between the rotary compressor and the pneumatic expander is realized, the spring is eliminated in the pneumatic expander, the complicated expansion spring mounting step is omitted, the axial length of the expander is reduced, and the whole machine is more compact.

Specifically, referring to FIG. 6, in some embodiments, the outer side of compression end cap 610 is provided with a hollow rigid tubular projection 611 that is concentric with compression end cap 610. Wherein the hard tubular protrusion 610 may have an outer diameter of 3-4 mm and a length of 5-8 mm.

Referring to fig. 2, in some embodiments, a rotary compressor 200 may include at least: a motor assembly, a compression piston assembly, and a compression end cap 220; wherein the motor assembly is connected to the compression piston assembly and drives the compression piston assembly to reciprocate such that gas within the rotary compressor is compressed and flows out of the rotary compressor through the hollow rigid tubular boss 221 on the compression end cap 220.

Specifically, the motor assembly may include a rotating motor and motor shaft 202; the compression piston assembly may include: compressing the piston 211 and the connecting rod assembly 212. Wherein the linkage assembly 212 further comprises a compression linkage and a compression pin.

The interior space of the base forms a closed compression chamber with the compression piston 211 and the compression end cap 220, which communicates with the pneumatic expander through a hollow rigid tubular boss 221. The compression end cover 220 is arranged at one end of the cavity, and the hollow hard tubular protrusion 221 communicated with the pneumatic expander is arranged outside the compression end cover 220, so that the pneumatic expander can be welded with the rotary compressor according to the set angle requirement, and the welding direction of the pneumatic expander can be changed by 360 degrees around the hollow hard tubular protrusion 221. When gas is transferred under pressure from the rotary compressor to the pneumatic expander via the hollow rigid tubular boss 221, the expansion end is able to adjust the phase angle between the expansion piston and the compression piston by the gas force. Because the transmission paths are all hard pipelines, the cold finger angle is convenient to control and adjust.

In the working process, the compression connecting rod is matched with the motor rotating shaft 202 through a bearing, the rotating motor provides rotating power, the motor rotating shaft 202 is driven by the rotating motor to rotate, the compression connecting rod further converts the rotating motion into reciprocating motion, the compression piston 211 is driven to reciprocate in the compression cavity to form a gas pressure wave, and gas in the compression cavity is compressed periodically and flows to the pneumatic expander along the hollow hard tubular protrusion 221.

In some embodiments, the compression piston 211 is connected to the compression connecting rod through a compression pin, and a double-row bearing is arranged on the compression connecting rod, so that the central position of the compression piston 211 can be automatically retrieved when the compression piston runs in the compression cavity.

In some embodiments, a counterweight may also be provided on the eccentric shaft of the motor shaft for balancing the inertial forces due to the rotational movement.

Referring to fig. 3, in some embodiments, a pneumatic expander 300 may include: expansion base 301, expansion cylinder 302, expansion piston 303, regenerator 304, and cold finger cylinder 305.

The cold finger cylinder 305 is located outside and is in clearance fit with the regenerator 304. In some embodiments, 0.05-0.08mm may be employed as the gap.

Wherein the regenerator 304 is connected to the expansion piston 303 and is reciprocable in the cold finger cylinder 305. In some embodiments the expansion piston 303 is connected to the regenerator 304 by gluing. The regenerator 303 may be internally filled with a uniform and closely arranged regenerator packing, such as a mesh of stainless steel woven wire mesh.

Wherein the expansion piston 303 is disposed in the expansion cylinder 302 and is in a clearance fit with the expansion cylinder 302, for example, a clearance value of 3-5 microns may be used. In some embodiments, the expansion piston 303 is a stepped shaft structure. Referring to fig. 4, in still other embodiments, the expansion piston stepped shaft junction is further designed with a clearance structure 306, the clearance amount being 0.2-0.3mm.

Compressed gas introduced through the rotary compressor is transferred into the expansion cylinder 302 through the expansion base 301, then flows into the regenerator 304 under the compression of the expansion piston 303, and finally enters the expansion chamber formed by the regenerator 304 and the cold finger cylinder 305.

In some embodiments, the expansion base 301 of the pneumatic expander has openings that mate with rigid tubular projections on the compression end cap and are attached and sealed by laser welding. Specifically, the relative direction of the expansion base and the compression end cover can be determined according to the installation direction of the expansion machine, and finally the welding of the expansion base and the compression end cover is finished. In some embodiments, welding may be performed in the opposite direction with reference to fig. 5 a-5 c.

According to some embodiments of the utility model, during actual operation, helium gas at a certain pressure is first filled in the Stirling refrigerator, and the helium gas is sealed in the machine in a metal sealing mode. When the rotary motor starts to work, the rotary motor drives the motor rotating shaft to do rotary motion, and the motor rotating shaft drives the compression piston to do reciprocating motion through the compression piston assembly to generate pressure waves. The air flow flows into the pneumatic expansion machine through the hollow hard tubular bulge on the compression end cover, then enters the cold accumulator through the air flow channel in the expansion piston, and pressure drop is generated after the air flow passes through the cold accumulator, so that pressure difference is generated at the cold and hot ends of the expansion machine. The differential pressure across the piston will give the expansion piston an impulse. The alternating flow of air flow makes the expansion piston drive the connecting rod to reciprocate in the expander, so that refrigeration is realized.

According to the utility model, the expansion end and the compression end are combined into a whole through the hollow hard tubular bulge on the compression cover by welding, so that a separate pipe is eliminated, and the machine has the compact characteristic of an integral Stirling refrigerator and the characteristic that the pneumatic expander can randomly adjust the cold finger installation angle. In addition, the structure makes the pneumatic expander not need to be provided with springs, so that not only is the complex expansion spring installation process eliminated, but also the axial length of the expander is reduced, and the whole machine is more compact.

On the other hand, the rotary compressor and the pneumatic expander are independently assembled and then connected, so that the assembly process is simplified, and the assembly efficiency is improved.

The foregoing is merely illustrative of the preferred embodiments of the present utility model and is not intended to limit the embodiments and scope of the present utility model, and it should be appreciated by those skilled in the art that equivalent substitutions and obvious variations may be made using the description and illustrations herein, which should be included in the scope of the present utility model.

Claims (10)

1. A pneumatic stirling cooler comprising:

the rotary compressor at least comprises a motor assembly, a compression piston assembly and a compression end cover, wherein a hollow hard tubular bulge is arranged on the outer side of the compression end cover;

the pneumatic expander at least comprises a base, a piston assembly, a cold accumulator and a cold finger cylinder; the pneumatic expander is connected with the rotary compressor by welding through a hard tubular bulge on the compression end cover;

the motor assembly is used for driving the compression piston to reciprocate, and pressure waves are generated and are led into the pneumatic expander through the hard tubular bulge, so that the expansion piston of the pneumatic expander reciprocates.

2. The pneumatic stirling cooler of claim 1 wherein the pneumatic expander is welded around the rigid tubular boss at a set angle.

3. The pneumatic stirling cooler of claim 1 wherein the pneumatic force generated by the rotary compressor is used as a drive source to drive the piston assembly of the pneumatic expander to reciprocate.

4. The pneumatic stirling cooler of claim 1 wherein the expansion mount of the pneumatic expander is provided with openings that mate with rigid tubular bosses on the compression end cap and are welded and sealed.

5. The pneumatic stirling cooler of claim 1 wherein said pneumatic expander and said rotary compressor are separate units, and are assembled separately and welded together.

6. The pneumatic stirling cooler of claim 1, wherein the rigid tubular boss (610) has an outer diameter of 3-4 mm and a length of 5-8 mm.

7. A pneumatic stirling cooler according to claim 1 wherein the cold finger cylinder is in a clearance fit with the regenerator.

8. A pneumatic stirling cooler according to claim 1 wherein the regenerator is adhesively connected to the expansion piston for reciprocation within the cold finger cylinder.

9. A pneumatic stirling cooler according to claim 1 wherein the expansion piston is of stepped shaft construction.

10. The pneumatic stirling cooler of claim 9 wherein said expansion piston stepped shaft junction is configured with a clearance configuration.