Free piston Stirling heat pump structure

Abstract

The invention relates to the technical field of heat pumps, and provides a free piston Stirling heat pump structure which comprises a heat pump unit and a compressor unit, the heat pump unit comprises a heat exchange device, a discharger and a base, a containing space is limited in the heat exchange device, the discharger is located in the containing space, and a compression cavity and an expansion cavity are formed in the two ends of the discharger respectively; a containing cavity is formed in the discharger, the base is fixed to the heat pump shell and embedded in the containing cavity, so that a gas spring cavity is formed in the containing cavity, and the gas spring cavity is used for providing axial elastic force needed by operation for the discharger; an air floatation gap is formed between the base and the discharger, is communicated with the gas spring cavity, and is used for providing radial supporting force required by operation for the discharger; the compressor unit is connected with the heat pump unit and used for transmitting acoustic power and pressure fluctuation into the compression cavity. Sufficient axial elastic force and radial supporting force can be provided, and normal operation of the discharger under the high-power working condition can be ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pumps, and particularly to a free piston Stirling heat pump structure. Background Art

[0002] An electrically driven free piston Stirling heat pump structure includes a heat pump unit and a compressor unit which are connected to each other. Its working principle is as follows: an alternating current is applied to the compressor unit, and a continuously changing magnetic field is generated by the copper coil. The electromagnetic force drives the power piston to reciprocate, thereby transmitting acoustic work and pressure fluctuations to the compression chamber. The acoustic work sequentially passes through the displacer, the low-temperature heat exchanger, the regenerator, and the high-temperature heat exchanger, and is utilized in the regenerator to produce a pumping heat effect. Finally, the heat is transferred from the low-temperature heat exchanger to the high-temperature heat exchanger and output to an external device.

[0003] Since the displacer is always in a reciprocating motion state when the free piston Stirling heat pump operates normally, it is necessary to provide an axial reciprocating elastic force for the displacer. And because the gap between the displacer and the cylinder is very small, it is necessary to ensure the coaxiality of the displacer and the cylinder to minimize the friction loss between the displacer and the cylinder. Therefore, it is also necessary to provide a radial supporting force for the displacer.

[0004] In the related art, multiple leaf springs arranged in an overlapping manner are used to provide the axial elastic force and radial supporting force required for the operation of the displacer. Since the sizes and required stiffnesses of the displacers of heat pumps with different power levels are different, for this reason, the structure, size, and the number of overlapping leaf springs are changed to meet the corresponding stiffness requirements. However, as the power level of the free piston Stirling heat pump increases, the size of its displacer and the stiffness requirement for the spring increase significantly, and the leaf springs used in the current technology are difficult to meet its stiffness requirements. Secondly, due to the increase in the size of the leaf spring and the increase in the moving mass, new tests will be imposed on its own structural design and service life. These problems restrict the development of the free piston Stirling heat pump towards a higher power level. Summary of the Invention

[0005] The present invention provides a free piston Stirling heat pump structure to solve the above technical defects in the prior art, and can provide sufficient axial elastic force and radial supporting force to ensure that the displacer can operate normally under high-power working conditions.

[0006] The present invention provides a free piston Stirling heat pump structure, including: A heat pump unit, comprising a heat exchange device, an expander and a base. An accommodation space is defined inside the heat exchange device. The expander is located in the accommodation space, and a compression chamber and an expansion chamber are respectively formed at two ends of the expander. An accommodation chamber is configured inside the expander. The base is fixed to the heat pump housing and embedded in the accommodation chamber to form a gas spring chamber in the accommodation chamber. The gas spring chamber is used to provide the axial elastic force required for the operation of the expander. An air bearing gap is formed between the base and the expander. The air bearing gap is communicated with the gas spring chamber and is used to provide the radial supporting force required for the operation of the expander. A compressor unit, connected to the heat pump unit, is used to transfer acoustic power and pressure fluctuations into the compression chamber.

[0007] According to the free piston Stirling heat pump structure provided by the present invention, the base comprises a first base body, a second base body and a connecting portion. The first base body and the second base body are perpendicularly connected to two ends of the connecting portion. The first base body is fixedly connected to the heat pump housing. The second base body is embedded in the accommodation chamber. The gas spring chamber is divided into a first sub-gas spring chamber and a second sub-gas spring chamber. The first sub-gas spring chamber is formed on one side of the second base body, and the second sub-gas spring chamber is formed on the other side of the second base body. An air bearing gap is formed between the second base body and the expander. The air bearing gap is respectively communicated with the first sub-gas spring chamber and the second sub-gas spring chamber.

[0008] According to the free piston Stirling heat pump structure provided by the present invention, a first gas flow channel is configured inside the connecting portion. A plurality of second gas flow channels are configured inside the second base body. One ends of the plurality of second gas flow channels are communicated with the first gas flow channel, and the other ends of the plurality of second gas flow channels are communicated with the air bearing gap.

[0009] According to the free piston Stirling heat pump structure provided by the present invention, each of the second gas flow channels extends along the radial direction of the second base body to form outlets arranged at equal intervals on the outer circumferential surface of the second base body.

[0010] According to the free piston Stirling heat pump structure provided by the present invention, when the compression chamber is located between the first base body and the compressor unit, the first gas flow channel extends along the axis of the connecting portion and penetrates through the first base body to be communicated with the compression chamber. When the compression chamber is located between the first base body and the second base body, the first gas flow channel extends along the axis of the connecting portion and extends out from the side wall of the connecting portion to be communicated with the compression chamber.

[0011] According to the free piston Stirling heat pump structure provided by the present invention, an adjustment air passage is further constructed inside the ejector. One end of the adjustment air passage communicates with the gas spring chamber, and the other end of the adjustment air passage communicates with the compression chamber; A one-way valve is provided on the adjustment air passage, and the one-way valve is used to control the flow of the gas in the compression chamber to the gas spring chamber through the adjustment air passage.

[0012] According to the free piston Stirling heat pump structure provided by the present invention, the heat exchange device includes a low-temperature heat exchanger, a regenerator, and a high-temperature heat exchanger. The accommodating space is surrounded by the low-temperature heat exchanger, the regenerator, and the high-temperature heat exchanger; The low-temperature heat exchanger, the regenerator, and the high-temperature heat exchanger are arranged in sequence from top to bottom; or, the low-temperature heat exchanger, the regenerator, and the high-temperature heat exchanger are arranged in sequence from bottom to top.

[0013] According to the free piston Stirling heat pump structure provided by the present invention, the compressor unit includes a linear oscillating motor and a power piston. Driven by the linear oscillating motor, the power piston reciprocates to transmit acoustic work and pressure fluctuations to the compression chamber.

[0014] According to the free piston Stirling heat pump structure provided by the present invention, there is one compressor unit, and the movement direction of the power piston is collinear with the axis of the heat pump unit.

[0015] According to the free piston Stirling heat pump structure provided by the present invention, there are two compressor units symmetrically arranged. Both of the two compressor units are connected to the heat pump unit, and the movement direction of each power piston is perpendicular to the axis of the heat pump unit.

[0016] In the free piston Stirling heat pump structure provided by the present invention, a accommodating cavity is constructed inside the ejector. The base is fixed to the heat pump housing and embedded in the accommodating cavity to form a gas spring chamber in the accommodating cavity for providing the axial elastic force required for the operation of the ejector; and an air bearing gap is formed between the base and the ejector. The base is provided with a gas flow passage, and the gas flow passage communicates with the air bearing gap and the compression chamber for providing the radial supporting force required for the operation of the ejector.

[0017] When the ejector is subjected to an axial force, the gas spring chamber can adjust its own compression amount according to the magnitude of the force, so as to provide a reaction force balanced with the axial force, effectively ensuring that the ejector has sufficient axial stiffness. This stiffness can be adjusted according to the actual working power and working conditions of the heat pump.

[0018] When the ejector is subject to a radial force, a uniform air film is formed in the air floating gap around the ejector. The air film can effectively disperse these forces, keeping the ejector stable in the radial direction and preventing direct contact with the base to avoid friction. This air floating support method can provide sufficient radial support force to ensure the normal operation of the ejector under high-power conditions.

[0019] Compared with improving the traditional leaf spring structure to meet the requirements of high-power heat pumps, the free-piston Stirling heat pump structure provided by the present invention has a relatively simple design and lower processing difficulty. Special processing techniques and high-end processing equipment are not required. It is mainly based on gas sealing and cavity structure design and can be realized through airway design and surface treatment.

[0020] In terms of cost, since the free-piston Stirling heat pump structure provided by the present invention does not require the use of expensive high-performance materials and complex processing techniques, and with relatively low processing difficulty, its transformation cost is also relatively low. There is no need to conduct a large-scale redesign of the entire heat pump system. Only a moderate transformation of the ejector part is required to effectively solve the problem that the traditional leaf spring structure is difficult to meet the stiffness requirements of the ejector of high-power heat pumps. Brief Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a schematic structural diagram of the free-piston Stirling heat pump structure provided by Embodiment 1 of the present invention.

[0023] Figure 2 It is a schematic structural diagram of the free-piston Stirling heat pump structure provided by Embodiment 2 of the present invention.

[0024] Figure 3 It is a schematic structural diagram of the free-piston Stirling heat pump structure provided by Embodiment 3 of the present invention.

[0025] Reference Signs: 10, heat pump unit; 11, low-temperature heat exchanger; 12, regenerator; 13, high-temperature heat exchanger; 14, ejector; 15, base; 151, first base body; 152, second base body; 153, connecting portion; 154, first gas flow channel; 155, second gas flow channel; 16, compression chamber; 17, expansion chamber; 18, gas spring chamber; 181, first sub-gas spring chamber; 182, second sub-gas spring chamber; 19, air floating gap; 120, adjustment airway; 121, check valve; 20. Compressor unit; 21. Linear oscillating motor; 22. Power piston. Specific embodiments

[0026] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0027] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0028] In the embodiments of the present application, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "under" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0029] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without conflict, those skilled in the art may combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0030] Figure 1 It is a schematic structural diagram of the free piston Stirling heat pump structure provided by Embodiment 1 of the present invention. Figure 2It is a schematic structural diagram of the free-piston Stirling heat pump structure provided in the second embodiment of the present invention.

[0031] Refer to Figure 1 and Figure 2 The present invention provides a free-piston Stirling heat pump structure. The free-piston Stirling heat pump structure includes a heat pump unit 10 and a compressor unit 20.

[0032] The heat pump unit 10 includes a heat exchange device, a displacer 14, and a base 15. An accommodation space is defined inside the heat exchange device. The displacer 14 is located in the accommodation space. Compression chambers 16 and expansion chambers 17 are respectively formed at both ends of the displacer 14. An accommodation cavity is formed inside the displacer 14. The base 15 is fixed to the heat pump housing and embedded in the accommodation cavity to form a gas spring cavity 18 in the accommodation cavity. The gas spring cavity 18 is used to provide the axial elastic force required for the operation of the displacer 14. An air bearing gap 19 is formed between the base 15 and the displacer 14. The base 15 is provided with a gas flow channel, and the gas flow channel is communicated with the air bearing gap 19 and the compression chamber 16. The air bearing gap 19 is used to provide the radial supporting force required for the operation of the displacer 14.

[0033] The compressor unit 20 is connected to the heat pump unit 10, and the compressor unit 20 is used to transmit acoustic power and pressure fluctuations into the compression chamber 16.

[0034] It can be understood that in the free-piston Stirling heat pump structure provided by the embodiments of the present invention, an accommodation cavity is formed inside the displacer 14. The base 15 is fixed to the heat pump housing and embedded in the accommodation cavity to form a gas spring cavity 18 in the accommodation cavity, which is used to provide the axial elastic force required for the operation of the displacer 14. And an air bearing gap 19 is formed between the base 15 and the displacer 14. The base 15 is provided with a gas flow channel, and the gas flow channel is communicated with the air bearing gap 19 and the compression chamber 16, which is used to provide the radial supporting force required for the operation of the displacer 14.

[0035] When the displacer 14 is subjected to an axial force, the gas spring cavity 18 can adjust its own compression amount according to the magnitude of the force, so as to provide a reaction force balanced with the axial force, effectively ensuring that the displacer 14 has sufficient axial stiffness. This stiffness can be adjusted according to the actual working power and working conditions of the heat pump.

[0036] When the displacer 14 is subjected to a radial force, a uniform air film is formed in the air bearing gap 19 around the displacer 14. The air film can effectively disperse these forces, keeping the displacer 14 stable in the radial direction and preventing it from directly contacting the base 15 to cause friction. This air bearing support method can provide sufficient radial supporting force to ensure that the displacer 14 can operate normally under high-power working conditions.

[0037] Compared with improving the traditional leaf spring structure to meet the needs of high-power heat pumps, the free piston Stirling heat pump provided by the present invention has a relatively simple structure design and low processing difficulty. No special processing technology and high-end processing equipment are required. It is mainly based on gas sealing and cavity structure design, which can be achieved through airway design and surface treatment.

[0038] In terms of cost, since the free piston Stirling heat pump structure provided by the present invention does not need to use expensive high-performance materials and complex processing technology, its transformation cost is relatively low under the condition of relatively low processing difficulty. It is not necessary to redesign the entire heat pump system on a large scale, and only a moderate transformation of the ejector 14 is required to effectively solve the problem that the traditional leaf spring structure is difficult to meet the stiffness requirements of the high-power heat pump ejector 14.

[0039] Continue reading Figure 1 and Figure 2 In some embodiments of the present invention, the base 15 includes a first base 151, a second base 152 and a connecting portion 153, and the first base 151 and the second base 152 are vertically connected at both ends of the connecting portion 153 to form a structure similar to an "I" shape.

[0040] The first base 151 is fixedly connected to the heat pump housing, that is, the first base 151 is directly connected to the heat pump housing, or is connected to the heat pump housing through a heat pump flange, the second base 152 is embedded in the accommodating cavity, and the gas spring cavity 18 is divided into a first sub-gas spring cavity 181 (upper gas spring cavity) and a second sub-gas spring cavity 182 (lower gas spring cavity), the first sub-gas spring cavity 181 is formed on one side of the second base 152, and the second sub-gas spring cavity 182 is formed on the other side of the second base 152.

[0041] An air floating gap 19 is formed between the second base body 152 and the ejector 14 , and the air floating gap 19 is communicated with the first partial gas spring chamber 181 and the second partial gas spring chamber 182 , respectively.

[0042] This is equivalent to improving the existing leaf spring base 15 into an I-shaped base 15 in the embodiment of the present invention, and the second base 152 of the base 15 is embedded in the accommodation chamber of the ejector 14 to divide the accommodation chamber into a first gas spring chamber 181 and a second gas spring chamber 182. When the ejector 14 reciprocates, the first gas spring chamber 181 and the second gas spring chamber 182 are respectively compressed to obtain corresponding restoring stiffness. The restoring stiffness of the ejector 14 can be adjusted by adjusting the cavity size of the first gas spring chamber 181 and the second gas spring chamber 182 in the ejector 14 to adjust the stiffness of the gas spring, thereby meeting the stiffness requirements of the ejector 14 required by the heat pump at different power levels.

[0043] The first sub-gas spring chamber 181 and the second sub-gas spring chamber 182 utilize the principles of static and dynamic pressures of gas to form a stable gas film support in the axial direction of the ejector 14. When the ejector 14 is subjected to an axial force, the gas film can withstand a certain pressure and provide a corresponding axial support force. Moreover, the gas spring can adjust its own compression amount according to the magnitude of the force, so as to provide a reaction force balanced with the axial force, effectively ensuring that the ejector 14 has sufficient axial stiffness.

[0044] Continue to refer to Figure 1 and Figure 2 In some embodiments of the present invention, a first gas flow channel 154 is constructed inside the connecting portion 153, and a plurality of second gas flow channels 155 are constructed inside the second base 152. One end of the plurality of second gas flow channels 155 is communicated with the first gas flow channel 154, and the other end of the plurality of second gas flow channels 155 is communicated with the air bearing gap 19.

[0045] Among them, each second gas flow channel 155 extends along the radial direction of the second base 152 to form outlets arranged at equal intervals on the outer circumferential surface of the second base 152.

[0046] In the embodiments of the present invention, the air bearing gap 19 plays an important role in the radial direction. By forming a uniform gas film around the second base 152, it can provide an all-round radial support for the ejector 14. When the ejector 14 is subjected to a radial force, the gas film can effectively disperse these forces, keeping the ejector 14 in a stable position radially and avoiding direct contact with the second base 152 to generate friction.

[0047] In a high-power heat pump, the ejector 14 needs to bear a large force. Due to its own material properties and structural form, the axial stiffness of the traditional leaf spring structure may be difficult to meet the requirements when facing the working demands of a high-power heat pump. Insufficient axial stiffness will cause the ejector 14 to generate a large axial displacement during operation, affecting the normal operation of the heat pump. For example, it may cause inaccuracies in the compression and expansion processes, thereby reducing the efficiency of the heat pump.

[0048] For the radial direction, the leaf spring structure may not be able to provide sufficient support force. However, when the ejector 14 is working, in addition to the axial force, it will also be subjected to a radial force, such as a radial force generated due to uneven working fluid flow or mechanical vibration. If the radial support force is insufficient, the ejector 14 may have abnormal friction or collision with the cylinder wall, resulting in increased component wear and reduced service life.

[0049] Therefore, by improving the structure of the base 15 and the structure of the ejector 14, an air-floating support is formed between the base 15 and the ejector 14. This air-floating support method can provide sufficient axial elastic force and radial support force for the heat pump, ensuring the normal operation of the ejector 14 under high-power working conditions. It meets the requirements for the development of the free-piston Stirling heat pump structure towards high power, large temperature span, and high efficiency, and can effectively solve the problem of insufficient stiffness of the leaf spring of the ejector 14 in the free-piston Stirling heat pump structure under high-power conditions.

[0050] Figure 3 It is a schematic structural diagram of the free-piston Stirling heat pump structure provided in Embodiment 3 of the present invention.

[0051] Refer to Figure 3 , in some embodiments of the present invention, an adjustment air passage 120 is further constructed inside the ejector 14. One end of the adjustment air passage 120 communicates with the gas spring chamber 18, and the other end of the adjustment air passage 120 communicates with the compression chamber 16; a check valve 121 is provided on the adjustment air passage 120. The check valve 121 is used to control the flow of the gas in the compression chamber 16 through the adjustment air passage 120 to the gas spring chamber 18, so as to realize taking air from the compression chamber 16 to the gas spring chamber 18 and realize the stiffness adjustment of the gas spring to meet the stiffness requirements of the ejector 14 required by the heat pump under different power levels.

[0052] Continue to refer to Figure 1 , the heat exchange device includes a low-temperature heat exchanger 11, a regenerator 12, and a high-temperature heat exchanger 13. The accommodation space is surrounded by the low-temperature heat exchanger 11, the regenerator 12, and the high-temperature heat exchanger 13; the low-temperature heat exchanger 11, the regenerator 12, and the high-temperature heat exchanger 13 are arranged in sequence from top to bottom, that is, the ejector 14 is arranged forward.

[0053] At this time, the compression chamber 16 is located between the first base 151 and the power piston 22 of the compressor unit 20. The first gas flow passage 154 extends along the axis of the connecting portion 153 and penetrates through the first base 151 to communicate with the compression chamber 16. The air-floating gap 19 can take air from the compression chamber 16 through the first gas flow passage 154 and the second gas flow passage 155.

[0054] Continue to refer to Figure 2 , the heat exchange device includes a low-temperature heat exchanger 11, a regenerator 12, and a high-temperature heat exchanger 13. The accommodation space is surrounded by the low-temperature heat exchanger 11, the regenerator 12, and the high-temperature heat exchanger 13; the low-temperature heat exchanger 11, the regenerator 12, and the high-temperature heat exchanger 13 are arranged in sequence from bottom to top, that is, the ejector 14 is arranged reversely.

[0055] At this time, the compression chamber 16 is located between the first base body 151 and the second base body 152. The first gas flow channel 154 extends along the axis of the connecting portion 153 and protrudes from the side wall of the connecting portion 153 to communicate with the compression chamber 16. The aerostatic gap 19 takes air from the compression chamber 16 through the first gas flow channel 154 and the second gas flow channel 155.

[0056] Refer to Figures 1 to 3 , in some embodiments of the present invention, the compressor unit 20 includes a linear oscillating motor 21 and a power piston 22. The power piston 22 reciprocates under the drive of the linear oscillating motor 21 to transmit acoustic power and pressure fluctuations into the compression chamber 16.

[0057] Among them, one compressor unit 20 is provided, and the movement direction of the power piston 22 is collinear with the axis of the heat pump unit 10. Such a setting forms a single-compressor type free piston Stirling heat pump structure, which is more compact.

[0058] Two compressor units 20 can also be symmetrically provided. Both compressor units 20 are connected to the heat pump unit 10, and the movement direction of each power piston 22 is perpendicular to the axis of the heat pump unit 10. Such a setting forms an opposed-compressor type free piston Stirling heat pump structure, which increases the thermal resistance between the heat pump unit 10 and the compressor unit 20 and reduces the conduction and diffusion of the gas heat in the compression chamber 16 to the motor side of the compressor unit 20.

[0059] In addition, the compression chamber 16 can be elongated to increase the distance between the high-temperature region of the heat pump unit 10 and the motor of the compressor unit 20. At the same time, a heat insulation cylinder can be added to the power piston 22 of the compressor unit 20 to reduce the heat transfer to the motor side, effectively reducing the working environment temperature on the compressor unit 20 side, enabling the compressor unit 20 to operate in a temperature range with relatively high performance as much as possible, improving the stability of the free piston Stirling heat pump structure, realizing the efficient operation of the heat pump, and extending the service life of the heat pump structure during ultra-high temperature pumping heat.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A free piston Stirling heat pump structure, characterized in that: include: A heat pump unit comprises a heat exchange device, an ejector and a base, wherein an accommodation space is limited inside the heat exchange device, the ejector is located in the accommodation space, and a compression chamber and an expansion chamber are respectively formed at two ends of the ejector; an accommodation chamber is constructed inside the ejector, the base is fixed to the heat pump housing, and is embedded in the accommodation chamber to form a gas spring chamber in the accommodation chamber, and the gas spring chamber is used to provide the ejector with an axial elastic force required for operation; an air floating gap is formed between the base and the ejector, the air floating gap is connected to the gas spring chamber, and the air floating gap is used to provide the ejector with a radial supporting force required for operation; A compressor unit is connected to the heat pump unit, and the compressor unit is used to transmit acoustic work and pressure fluctuations into the compression chamber.

2. The free piston Stirling heat pump structure according to claim 1, characterized in that: The base comprises a first base, a second base and a connecting portion, wherein the first base and the second base are vertically connected at two ends of the connecting portion; The first substrate is fixedly connected to the heat pump housing, the second substrate is embedded in the accommodating cavity, the gas spring cavity is divided into a first sub-gas spring cavity and a second sub-gas spring cavity, the first sub-gas spring cavity is formed on one side of the second substrate, and the second sub-gas spring cavity is formed on the other side of the second substrate; An air floating gap is formed between the second base and the ejector, and the air floating gap is communicated with the first sub-gas spring chamber and the second sub-gas spring chamber respectively.

3. The free piston Stirling heat pump structure according to claim 2, characterized in that: The connecting portion has a first gas flow channel inside, the second substrate has a plurality of second gas flow channels inside, one end of the plurality of second gas flow channels is connected to the first gas flow channel, and the other end of the plurality of second gas flow channels is connected to the air floating gap.

4. The free piston Stirling heat pump structure according to claim 3, characterized in that: Each of the second gas flow channels extends in the radial direction of the second substrate to form outlets arranged at equal intervals on the outer peripheral surface of the second substrate.

5. The free piston Stirling heat pump structure according to claim 3, characterized in that: When the compression chamber is located between the first base and the compressor unit, the first gas flow channel extends along the axis of the connecting portion, passes through the first base, and communicates with the compression chamber; When the compression chamber is located between the first substrate and the second substrate, the first gas flow channel extends along the axis of the connecting portion and extends from the side wall of the connecting portion to communicate with the compression chamber.

6. The free piston Stirling heat pump structure according to any one of claims 1 to 5, characterized in that: The ejector is also provided with an adjusting air passage inside, one end of which is in communication with the gas spring chamber, and the other end of which is in communication with the compression chamber; A one-way valve is provided on the regulating air passage, and the one-way valve is used to control the gas in the compression chamber to flow to the gas spring chamber through the regulating air passage.

7. The free piston Stirling heat pump structure according to any one of claims 1 to 5, characterized in that: The heat exchange device comprises a low-temperature heat exchanger, a regenerator and a high-temperature heat exchanger, and the accommodating space is surrounded by the low-temperature heat exchanger, the regenerator and the high-temperature heat exchanger; The low-temperature heat exchanger, the heat regenerator and the high-temperature heat exchanger are arranged in sequence from top to bottom; or, the low-temperature heat exchanger, the heat regenerator and the high-temperature heat exchanger are arranged in sequence from bottom to top.

8. The free piston Stirling heat pump structure according to any one of claims 1 to 5, characterized in that: The compressor unit includes a linear oscillation motor and a power piston. Driven by the linear oscillation motor, the power piston performs reciprocating motion to transmit acoustic work and pressure fluctuations into the compression chamber.

9. The free piston Stirling heat pump structure according to claim 8, characterized in that: The compressor unit is provided with a moving direction of the power piston being colinear with the axis of the heat pump unit.

10. The free piston Stirling heat pump structure according to claim 8, characterized in that: The compressor units are symmetrically provided with two, both of which are connected to the heat pump unit, and the movement direction of each power piston is perpendicular to the axis of the heat pump unit.

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