Refrigeration drive based on elastic snap material winding flexure

Abstract

The present disclosure relates to a refrigeration driver based on winding and bending of elastic material, comprising at least a pair of carriers, each carrier being arranged parallel to each other and being rotatable along an axis, and an elastic material strip, both ends of which are fixed on the pair of carriers, wherein the pair of carriers winds the elastic material strip on at least one carrier of the pair of carriers by rotating in a first direction, the part of the elastic material strip wound on the carrier releases heat to form a hot zone, and the pair of carriers unwinds the elastic material strip from at least one carrier of the pair of carriers by rotating in a second direction opposite to the first direction, the part of the elastic material strip unwound from the carrier absorbs heat to form a cold zone. The refrigeration driver of the present disclosure reduces driving force, realizes continuous high-frequency operation and automatically separates the hot zone and the cold zone.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of solid-state refrigeration, and particularly relates to a refrigeration driver based on winding and bending of elastic clamping material. BACKGROUND

[0002] In today's life, people have great demand for refrigeration, including using air conditioners to reduce room temperature or using refrigerators to store food at low temperature. However, the traditional gas compression refrigerators have many problems: on the one hand, the energy conversion rate of gas compression refrigeration is low, for example, the energy efficiency ratio of general air conditioner is about 3, and a large part of electric energy is wasted, causing waste of public resources; on the other hand, the refrigerant freon used in gas compression refrigerators is manufactured and leaked in large quantities, although it has no harm to the organism itself, but the earth's atmosphere has been irreversibly damaged due to the chemical action of this refrigerant, the content of ozone in the atmosphere has decreased sharply, which makes the ultraviolet rays directly irradiate the earth's surface in large quantities, the overall temperature of the earth rises, and more extreme weather, sea level rise and other problems are induced. In summary, a new generation of high-efficiency and environmentally friendly refrigeration technology has become an important prerequisite for sustainable development of mankind in the future.

[0003] The elastic clamping solid-state refrigeration technology is a new type of refrigeration technology using the endothermic and exothermic effect of material first-order phase transition. Since this new technology was proposed in 2004, it has attracted the attention of researchers around the world. The most important advantage is its high energy conversion rate and no additional damage to the environment. In recent years, research on elastic clamping solid-state refrigeration has obtained many research results and good refrigeration effect, but the problem of large driving force still hinders the further development of this technology.

[0004] For example, a research team from the University of Michigan designed and developed a refrigeration prototype based on the principle of compression of nickel-titanium alloy tube, using water as the heat exchange medium to obtain a maximum temperature difference of 4.7 K, but its huge driving force (68000 N) needs a large volume of hydraulic system to drive. A research team from the Technical University of Denmark reported in the journal Nature Energy in 2016 a kind of elastic card refrigeration system based on the tensile deformation of nickel-titanium alloy and using water to realize active heat recovery. The system generates a temperature difference of 15.3 K, but the system is only in the experimental test machine stage, and it needs a tensile force of 7200 N to drive 5.8 g of elastic card material, and the total refrigeration amount is also far lower than the daily refrigeration demand. Chinese patent CN201810660524.1 (publication number CN108954901A, publication date 2018.12.07) shows a kind of elastic card refrigeration device using nickel-titanium alloy tube compression deformation, the heat transfer medium uses water, through the axial reciprocating motion of the electric press, to compress the nickel-titanium alloy tube to make it compression deformation, and use the external water pump to push the water circulation to the nickel-titanium alloy tube for convective heat transfer. Similarly, the compression drive also has the problem of too large driving force (more than 10000 N), and the volume ratio between the electric press and the elastic card material exceeds 100:1, which does not meet the safety principle of further commercial development. SUMMARY

[0005] The present disclosure provides a kind of refrigeration driver based on the winding bending of elastic card material to solve at least one of the above problems, with low driving force, low temperature drop, continuous high frequency work and automatic separation of hot zone and cold zone etc.

[0006] According to one aspect of the present disclosure, a refrigeration driver based on the winding bending of elastic card material is provided, comprising at least: a pair of bearings, each bearing is arranged parallel to each other and can rotate along the axis, and an elastic card material strip, both ends of which are fixed on the pair of bearings, wherein the pair of bearings winds the elastic card material strip on at least one bearing of the pair of bearings by rotating in a first direction, the part of the elastic card material strip wound on the bearing releases heat to form a hot zone, and the pair of bearings unwinds the elastic card material strip from at least one bearing of the pair of bearings by rotating in a second direction opposite to the first direction, the part of the elastic card material strip unwound from the bearing absorbs heat to form a cold zone.

[0007] Optionally, the elastic card material strip is pre-wound on at least one bearing of the pair of bearings in the initial state.

[0008] Optionally, the pair of carriers are configured to: by rotation in the first direction, wind the elastic material strip on at least one of the pair of carriers while unwinding the pre-winding of the elastic material strip on the at least one of the pair of carriers; and subsequently by rotation in the second direction, reversely wind and unwind the elastic material strip.

[0009] Optionally, the refrigeration driver further comprises: a guide rail; a movable end slidably arranged on the guide rail, the movable end being provided with a motor, the motor driving the pair of carriers to rotate; and a fixed end fixed to the guide rail, wherein the carrier is rotatably connected to the fixed end, the fixed end being configured to convert the rotational motion of the carrier into linear motion of the carrier along an axis, so that the position of the cold zone relative to the guide rail remains unchanged when the refrigeration driver is in operation.

[0010] Optionally, one end of each of the pair of carriers is fixedly connected to the rotating end of the motor, and the other end is fixedly connected to the screw rod, and the fixed end has a threaded hole, the screw rod cooperating with the threaded hole of the fixed end to convert the rotational motion of the carrier into linear motion of the carrier along an axis.

[0011] Optionally, each of the pair of carriers has a threaded groove to accommodate the elastic material strip wound thereon, wherein one end of the elastic material strip is fixed to a first end of one of the pair of carriers, and the other end of the elastic material strip is fixed to a second end of the other of the pair of carriers opposite to the first end.

[0012] Optionally, the thread directions of the threaded grooves of each of the pair of carriers are consistent with each other and consistent with the thread direction of the screw rod.

[0013] Optionally, the thread pitches of the threaded grooves of each of the pair of carriers are consistent with the thread pitch of the screw rod.

[0014] Optionally, the elastic material strip comprises at least shape memory alloy, natural rubber, synthetic polymer, plastic crystal.

[0015] Optionally, the shape memory alloy is selected from the group consisting of nickel-titanium alloy, copper-aluminum-manganese alloy, nickel-manganese-titanium alloy, nickel-titanium-cobalt alloy.

[0016] Optionally, the cross section of the elastic material strip is rectangular or circular.

[0017] Optionally, when the cross section of the strip of elastic material is rectangular, the length of the strip of elastic material is significantly greater than its width and thickness; when the cross section of the strip of elastic material is circular, the length of the strip of elastic material is significantly greater than the diameter of the cross section.

[0018] Optionally, the pitch of the thread on the screw, the thread groove of the carrier, and the thread hole of the fixed end is in the range of 2.00 mm to 10.00 mm.

[0019] Optionally, the refrigeration driver further comprises a heat exchanger arranged in the cold zone and / or the hot zone.

[0020] Optionally, the heat exchanger comprises a fan and an air duct in gas communication with the fan, wherein the fan transports air into the air duct for convective heat exchange.

[0021] Optionally, the heat exchanger uses a fluid or solid heat exchanger.

[0022] Optionally, the strip of elastic material is a plurality of strips of elastic material, and the plurality of strips of elastic material are arranged between the pair of carriers.

[0023] Optionally, the refrigeration driver further comprises a concentrator that bundles the plurality of strips of elastic material into a parallel state.

[0024] Optionally, the refrigeration driver further comprises a plurality of pairs of carriers stacked on each other.

[0025] Compared with the prior art, the solid-state refrigeration driver of the present disclosure has the following characteristics:

[0026] 1. The refrigeration is achieved by the heat absorption effect of the strip of elastic material after contact and winding bending, which obtains a significant temperature drop. Compared with compression or stretching driving, the bending driving used by the refrigeration driver of the present disclosure reduces the driving force, and a small-sized driver can greatly reduce the overall volume.

[0027] 2. By controlling the size of the diameter of the carrier, the deformation degree of winding bending can be controlled, so that the daily refrigeration demand can be conveniently regulated and satisfied.

[0028] 3. The refrigeration driver of the present disclosure can realize continuous high-frequency operation, and can distinguish the hot zone and the cold zone without the help of heat exchange fluid, thereby avoiding the problem that the heat source and the cold source have the same spatial position in all previous elastic refrigeration, and greatly reducing the complexity of the heat exchange structure. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 (a) and Figure 1 (b) are schematic diagrams of the solid-state refrigeration driver of the exemplary embodiments of the present disclosure.

[0030] Figure 2 is a structural schematic diagram of a solid-state refrigeration driver of an exemplary embodiment of the present disclosure;

[0031] Figure 3 is a schematic diagram of a strip of elastic card material used in an exemplary embodiment of the present disclosure;

[0032] Figure 4 (a) and Figure 4 (b) show a schematic diagram of the temperature change of the hot zone and the cold zone of a solid-state refrigeration driver in an exemplary embodiment of the present disclosure before and during actual operation under the shooting of an infrared camera;

[0033] Figure 5 is a schematic diagram of the temperature change of the cold zone of a solid-state refrigeration driver in an exemplary embodiment of the present disclosure over time after a single refrigeration during actual operation;

[0034] Figure 6 is a schematic diagram of the temperature change of the cold zone of a solid-state refrigeration driver in an exemplary embodiment of the present disclosure over time during cyclic refrigeration during actual operation;

[0035] Figure 7 (a) and Figure 7 (b) is a schematic diagram of a refrigeration prototype machine in which multiple groups of solid-state refrigeration drivers are combined and air is used as a heat transfer fluid in an exemplary embodiment of the present disclosure, wherein Figure 7 (a) is a side view of the multiple groups of solid-state refrigeration drivers, Figure 7 (b) is a top view of the multiple groups of solid-state refrigeration drivers.

[0036] BRIEF DESCRIPTION OF DRAWINGS

[0037] 1 guide rail 2 motor 3 coupling 4 bearing 5 screw rod 6 bearing 7 elastic strip 8 fixed block 9 sliding block a hot zone b cold zone 10 hub 11 air duct 12 fan DETAILED DESCRIPTION

[0038] In order for those skilled in the art to better understand the technical solutions of the present disclosure, the refrigeration driver based on the winding and bending of elastic card material provided by the present disclosure will be described in detail below in conjunction with the drawings.

[0039] As Figure 1 (a) and Figure 1(b) as shown, which shows a schematic diagram of a solid-state refrigeration driver according to an exemplary embodiment of the present disclosure. The refrigeration driver based on the elastic material winding bending of the present disclosure at least includes: a pair of bearings 6, each bearing 6 is arranged parallel to each other and can rotate along the axis, and an elastic material strip 7, both ends of which are fixed on the pair of bearings 6, wherein, as viewed from the top view, the pair of bearings 6 winds the elastic material strip 7 on at least one bearing of the pair of bearings by clockwise rotation, and the pair of bearings 6 unwinds the elastic material strip 7 from at least one bearing of the pair of bearings by counterclockwise rotation. The part of the elastic material strip 7 wound on the bearing releases heat to form a hot zone a, and the part of the elastic material strip 7 unwound from the bearing absorbs heat to form a cold zone b.

[0040] Based on the principle of bending deformation, when an object is bent, one side is subjected to tensile deformation and the other side is subjected to compressive deformation, and the degree of overall bending deformation depends on the curvature of the object when it is bent, that is, the size of the corresponding curvature circle of the bending arc. As the diameter of the curvature circle decreases, the curvature of the corresponding object will increase accordingly, that is, the greater the degree of bending deformation of the object, the greater the corresponding tensile and compressive strain. The bearing 6 in the present disclosure corresponds to a curvature circle member. When the elastic material strip 7 is wound on the curvature circle member and closely attached to it, the surface of the strip will be subjected to corresponding tensile and compressive strain. When the degree of strain is large enough, the elastic effect will occur, that is, heat will be released, and then when the elastic material strip 7 leaves the curvature circle, the strain returns to the initial state, and the elastic material strip 7 will undergo reverse phase change and absorb heat. The diameter of the curvature circle, that is, the diameter of the cylindrical bearing, can be controlled to control the degree of strain on the surface of the elastic material strip, and thus the release of heat and cold by the refrigeration driver.

[0041] In actual working conditions, because the Young's modulus of the shape memory alloy changes constantly during the phase change, the bending neutral layer will drift to the compression side, which will cause the strain on the tensile side to be larger than the designed value. When the elastic material strip 7 is fixed on the left and right bearings 6, as shown in Figure 1 As shown, as viewed from the top view, as the two bearings 6 rotate clockwise or counterclockwise, the elastic material strip 7 will be wound on the left and right bearings 6 respectively due to the action of the torque, and will be subjected to bending deformation at this time. At this time, the elastic material strip wound on the bearing releases heat to form a hot zone a, and the elastic material strip straightened after unwinding absorbs heat to form a cold zone b.

[0042] The solid-state refrigeration driver of the present disclosure utilizes the heat absorption effect of the elastic clamping material strip after being wound and bent to achieve refrigeration. Compared with compression or stretching driving, the bending driving utilized by the refrigeration driver of the present disclosure reduces the driving force, and a small-sized driver can greatly reduce the overall volume. At the same time, the refrigeration driver of the present disclosure can realize continuous high-frequency operation, and can distinguish the hot area and the cold area without the help of heat exchange fluid. This is because the hot area a is formed in the part where the elastic clamping material strip 7 is wound on the carrier 6, and the cold area b is formed in the part where the elastic clamping material strip 7 is unwound from the carrier 6. The two parts of the elastic clamping material strip 7 are naturally separated, thereby avoiding the problem that the heat source and the cold source have the same spatial position in all previous elastic clamping refrigeration, and greatly reducing the complexity of the heat exchange structure.

[0043] Optionally, the elastic clamping material strip 7 is pre-wound on at least one of the pair of carriers 6 in an initial state. Here, the initial state refers to the state of the refrigeration driver before starting. The elastic clamping material strip 7 can be pre-wound on one or both of the pair of carriers 6. Thus, after the refrigeration driver is started, the cold energy can be immediately released as the pre-wound part of the elastic clamping material strip 7 is unwound from the carrier 6.

[0044] Optionally, the pair of carriers 6 are configured to: by rotating in a first direction, wind the elastic clamping material strip 7 on at least one of the pair of carriers 6, and simultaneously unwind the pre-winding of the elastic clamping material strip 7 on at least one of the pair of carriers 6; and then by rotating in a second direction, reversely wind and unwind the elastic clamping material strip 7. Here, the first direction is not limited to clockwise, and can also be counterclockwise, as long as the first direction is opposite to the second direction. The carrier 6 is configured to wind the elastic clamping material strip 7 while unwinding the pre-wound elastic clamping material strip 7. By reciprocating rotation in the first direction and the second direction, the carrier drives the elastic clamping material strip to complete a cycle. In this way, the reciprocating motion of the elastic clamping material strip can be continuously and effectively utilized to generate cold energy.

[0045] Optionally, as shown in Figure 2 The refrigeration driver further includes a guide rail 1, a movable end slidably arranged on the guide rail, the movable end being provided with a motor 2 driving the pair of carriers 6 to rotate, and a fixed end fixed to the guide rail 1, wherein the carrier 6 is rotatably connected to the fixed end, and the fixed end is configured to convert the rotary motion of the carrier 6 into the linear motion of the carrier 6 along the axis, so that the position of the cold area b relative to the guide rail 1 remains unchanged when the refrigeration driver is running. Generally, the guide rail 1 is arranged to be stationary relative to the ground, so that the cold area b can be stationary relative to the ground, i.e., the spatial position relative to the ground is unchanged. It can be understood that the position relationship of the guide rail relative to the ground is not limited here.

[0046] By designing the carrier 6 and the elastic material strip 7 wound thereon to move along the axis while rotating, the position of the cold zone b relative to the guide rail 1 is kept unchanged. This is conducive to the compactness of the structure itself and the design simplification of the optional heat exchange structure.

[0047] Optionally, as shown in Figure 2 , the fixed end is a bearing 4 fixedly connected to the guide rail 1 through a fixed block 8, and the movable end includes a sliding block 9 and a motor 2 arranged on the sliding block 9, and the sliding block 9 is slidably connected to the guide rail 1.

[0048] Optionally, one end of each carrier 6 in the pair of carriers is fixedly connected to the rotating end of the motor 2, and the other end is fixedly connected to the screw rod 5, and the fixed end has a threaded hole, and the screw rod 5 cooperates with the threaded hole of the fixed end to convert the rotary motion of the carrier 6 into the linear motion of the carrier 6 along the axis. Here, the rotating end of the motor is the torque output end. And here, "fixedly connected" is not specifically limited as long as the relative static state of the two being fixed can be guaranteed, for example, as shown in Figure 2 , one end of the carrier 6 can be fixedly connected to the rotating end of the motor 2 through a shaft coupling 3, and the other end of the carrier 6 can be fixedly connected to the screw rod 5 through the shaft coupling 3.

[0049] Optionally, each carrier 6 in the pair of carriers has a threaded groove to accommodate the elastic material strip 7 wound thereon, wherein one end of the elastic material strip 7 is fixed to the first end of one of the pair of carriers, and the other end of the elastic material strip 7 is fixed to the second end opposite to the first end of the other of the pair of carriers.

[0050] As shown in the enlarged view in Figure 2 , the left end of the elastic material strip 7 is fixed to the lower end (first end) of the left carrier of the pair of carriers, and the other end on the right side of the elastic material strip 7 is fixed to the upper end (second end) of the right carrier of the pair of carriers. Such a configuration helps to stably wind the elastic material strip 7 on the carrier 6.

[0051] Optionally, the two ends of the elastic material strip 7 can be fixed to the left and right carriers respectively by, for example, threaded connection, welding, gluing or other means. After the elastic material strip 7 is installed, the strip and the carrier form a stable structure, thereby improving the stability of the overall component under working conditions.

[0052] Optionally, the thread direction of the thread groove of each of the pair of carriers 6 is consistent with each other, and consistent with the thread direction of the screw rod 5. For example, as viewed from the top view, the thread of the screw rod 5 can be left-handed thread, i.e. the thread that is screwed in when rotated counterclockwise, which drives the motor 2 to move away from the fixed end when rotated counterclockwise, and drives the motor 2 to move towards the fixed end when rotated clockwise. In this case, the thread direction of the thread groove of each of the pair of carriers 6 is consistent with the thread direction of the screw rod 5, for example, both are left-handed thread. Of course, right-handed thread can also be used.

[0053] Such a configuration can make the position of the cold zone b of the refrigeration driver relative to the guide rail 1 remain unchanged regardless of whether the motor 2 outputs clockwise torque or counterclockwise torque. Specifically, for example Figure 2 As shown, the thread direction of the thread groove of each of the pair of carriers 6 is consistent with each other, and consistent with the thread direction of the screw rod 5, for example, both are left-handed thread. As viewed from the top view, when the motor 2 outputs clockwise torque, the motor 2, the carriers 6 and the elastic material strip 7 thereon, the screw rod 5 move together towards the fixed end (i.e. the lower direction in Figure 2 ), at this time, the elastic material strip 7 is continuously unwound from the left carrier 6 and moved to the right carrier 6, thereby the position of the cold zone b relative to the guide rail 1 can remain unchanged. When the motor 2 outputs counterclockwise torque, the motor 2, the carriers 6 and the elastic material strip 7 thereon, the screw rod 5 move together away from the fixed end (i.e. the upper direction in Figure 2 ), at this time, the elastic material strip 7 is continuously unwound from the right carrier 6 and moved to the left carrier 6 and wound thereon, thereby the position of the cold zone b relative to the guide rail 1 can remain unchanged as well. It can be understood that the case of using right-handed thread is similar, which will not be described here.

[0054] Optionally, the lead of the thread groove of each of the pair of carriers 6 is consistent with the lead of the screw rod 5.

[0055] The elastic material strip 7 is made of elastic material. The elastic material refers to a solid material that has elastic (thermal) effect. The elastic effect is one of the thermal effects of solid materials, which is driven by an external stress field, resulting in the release or absorption of heat after the material is strained. Compared with other thermal effects of solid materials, the elastic effect of the elastic material has the characteristic of high entropy change, which can greatly improve the energy conversion rate.

[0056] Optionally, the elastic material strip 7 at least includes shape memory alloy, natural rubber, synthetic polymer, plastic crystal. The shape memory alloy is a metal that can deform at room temperature but return to its original shape after heating. The shape memory alloy has two major characteristics, one is shape memory effect, and the other is superelasticity. In this case, the superelasticity of the shape memory alloy is utilized.

[0057] Optionally, the shape memory alloy is selected from the group consisting of nickel-titanium alloys, copper-aluminum-manganese alloys, nickel-manganese-titanium alloys, and nickel-titanium-cobalt alloys. In a specific embodiment, the spring clip material strip 7 can be made of, for example, a nickel-titanium shape memory alloy. Making the spring clip material strip 7 from these shape memory alloys can further reduce the required driving force while maintaining a certain cooling capacity.

[0058] Optionally, the cross-section of the spring clip material strip 7 can be rectangular or circular. These two shapes of spring clip material strips are relatively easy to fit with the load-bearing structure. Of course, the spring clip material strip can also adopt other cross-sectional shapes, as long as it facilitates the wrapping of the spring clip material strip around the load-bearing structure and allows for easy unwrapping from the load-bearing structure.

[0059] Optionally, when the cross-section of the spring-loaded material strip is rectangular, the length of the spring-loaded material strip 7 is significantly greater than its width and thickness. That is, as shown... Figure 3 As shown, the spring clip material strip 7 can be composed of long strip-shaped plates. For example, plates with a thickness of 0.50 mm, a length of 300.00 mm, and a width of 1.50 mm can be used. The width at both ends can be increased to 2.00 mm to increase the mechanical stability of the spring clip material strip 7 when fixed on the load 6. It should be understood that plates of other sizes can also be selected, provided that the corresponding proportions are met.

[0060] The bending deformation state of the spring-loaded material strip 7 during winding is determined by its curvature, which in turn is determined by the diameter of the bearing 6 and the thickness of the spring-loaded material strip 7. Given a fixed thickness, the bending curvature of the spring-loaded material strip 7 during winding deformation can be increased by reducing the diameter of the bearing 6, thereby achieving a greater cooling capacity. Figure 3 As shown, for the nickel-titanium shape memory alloy strip with a thickness of 0.50 mm selected exemplary in this disclosure, according to the material properties, a phase transformation will occur after the tensile surface undergoes a strain exceeding 5%, resulting in a spring-loaded effect. The required diameter for bearing the load can be roughly calculated using the following formula:

[0061]

[0062] For example, the load-bearing structure of this disclosure is based on a cylindrical design with a diameter of 10.00 mm. In this case, the length of the spring clip material strip 7 is approximately 300.00 mm, which is significantly greater than its width (1.50 mm) and thickness (0.50 mm). This construction of the spring clip material strip provides more possibilities for the design of the corresponding load-bearing structure and also provides greater flexibility in the selection of threads in other components.

[0063] In addition, the cross section of the elastic material strip is circular, and the length of the elastic material strip 7 is significantly greater than the diameter of the cross section. It should be understood that the geometry of the elastic material strip 7 can be determined by actual refrigeration requirements and device size.

[0064] Optionally, the screw 5, the thread groove of the bearing 6, and the thread pitch on the threaded hole of the fixed end are in the range of 2.00 mm to 10.00 mm. The displacement of the linear motion of the motor 2 with rotation is determined by the thread pitch of the screw 5, and the thread pitch on the screw 5, the bearing 4, and the bearing 6 can be consistent, and is generally selected to be within 2.00 mm to 10.00 mm. In the exemplary embodiment, the thread pitch is selected to be 4.00 mm.

[0065] Optionally, the refrigeration driver further comprises a heat exchanger arranged in the cold zone b and / or the hot zone a. The elastic material strip 7 may, due to the accumulation effect of heat after being cyclically wound, cause the temperature change to gradually decrease after the first turn, and thus the accumulation effect of heat can be reduced by arranging an additional heat exchange system in the hot zone a. The additional heat exchange structure can be a solid heat exchanger (heat transfer by direct solid-solid contact) or a fluid heat exchanger (heat transfer by solid-liquid convection using gas, liquid, liquid metal, etc.).

[0066] Figure 7 (a) and Figure 7 (b) shows a refrigeration prototype machine schematic diagram of a plurality of solid-state refrigeration driver combinations and application of air as a heat transfer fluid, wherein Figure 7 (a) is an isometric view of the refrigeration prototype machine, Figure 7 (b) is a top view of the corresponding refrigeration prototype machine.

[0067] Optionally, as Figure 7 (a) and Figure 7 (b) show, the elastic material strip 7 is a plurality of elastic material strips, and a plurality of elastic material strips are arranged between a pair of bearings. Thus, the spatial volume of the hot zone a and the cold zone b can be controlled by changing the geometry of the elastic material strip 7 and increasing or decreasing the number of elastic material strips. In Figures 1 to 6 the corresponding exemplary embodiment, one elastic material strip is selected to be installed on the bearing of the driver for exemplary demonstration, but the number of elastic material strips 7 is not limited thereto. Figure 7 The refrigeration prototype machine shown uses a plurality of elastic material strips to increase the refrigeration efficiency.

[0068] Optionally, as Figure 7 (a) and Figure 7(b) shows that the refrigeration driver also includes: multiple pairs of carriers 6 stacked with each other. This is conducive to increasing the overall refrigeration power. One or more strips of elastic material can be installed on each pair of carriers 6, depending on the desired space volume of the hot area a and the cold area b and the related design of the refrigeration efficiency.

[0069] Optionally, the refrigeration driver also includes: a hub 10 that bundles multiple strips of elastic material 7 into a parallel state with each other. As Figure 7 (b) shows that two hubs 10 are provided, each of which bundles multiple strips of elastic material 7 from the left carrier and the right carrier so that the multiple strips of elastic material 7 located between the two hubs 10 (i.e. the cold area b) are parallel to each other. This is conducive to subsequent heat transfer processes and the design of heat exchange components.

[0070] Optionally, the heat exchanger includes a fan 12 and an air duct 11 in gas communication with the fan 12, wherein the fan 12 transports air into the air duct 11 for convective heat exchange. As Figure 7 (b) shows that such a heat exchanger is provided in the cold area b, which effectively outputs the cold energy released by the elastic material strips in the form of cold air to achieve the effect of refrigeration. Optionally, the heat exchanger can also use a fluid or solid heat exchanger.

[0071] Optionally, at least one of the guide rail 1, the shaft 3, the bearing 4, the screw 5, the carrier 6, the fixed block 8 and the sliding block 9 can be formed by plastic, metal, resin or other materials through additive manufacturing (3D printing, etc.) or subtractive manufacturing (wire cutting, etc.). By using advanced manufacturing processes such as 3D printing, slow wire cutting, etc., the overall system accuracy can be improved, and lightweight design is also performed.

[0072] Optionally, the motor 2 can be a servo motor, a stepper motor, a torque motor, a switched reluctance motor, a direct current brushless motor, etc., or a mechanical device that can rotate. In the exemplary embodiment, the motor 2 is selected as a stepper motor, which has the advantages of fast rotation speed, programmable control, etc.

[0073] Optionally, the torque generated by the motor 2 should meet the minimum requirement of winding. In the exemplary embodiment, as Figure 3 The nickel-titanium strip of the size needs to be wound about 1 turn, which requires at least 0.20 Nm of torque.

[0074] Optionally, one refrigeration cycle of the refrigeration driver in actual work is from the motor 2 changes the direction of rotation to the next time the direction of rotation is changed.

[0075] Optionally, the time required for the actual operation of the refrigeration cycle of the refrigeration driver is determined by the distance between the two bearings 6 and the rotational speed of the motor 2. In the exemplary embodiment, the two bearings 6 are 75.00 mm apart, and the elastic material strip 7 is wound around the bearings 6 about 3 turns in each refrigeration cycle.

[0076] Optionally, the winding time (i.e. the loading time) can be approximately in the range of 0.20 ~ 10.00 s, and a static time can be added after each winding time according to the heat exchange requirement to fully transfer the heat.

[0077] The exemplary embodiments shown in Figure 2 will be further described below. As shown in Figure 2 , one working unit of the solid-state refrigeration driver includes a guide rail 1, a motor 2, a shaft coupling 3, a bearing 4, a screw rod 5, a bearing 6, an elastic material strip 7, a fixed block 8, and a sliding block 9, and all components in the working unit are installed on the guide rail. Among them, the area a and the area b are the hot area a and the cold area b formed under the working condition. In the specific installation example, the fixed block 8 and the sliding block 9 are installed on the guide rail 1, and the bearing 4 is installed on the fixed block 8 as a fixed end that cannot move. The motor 2 is installed on the sliding block 9, which can move forward and backward on the guide rail 1 in the axial direction. The rotating end of the motor 2 is connected to the bearing 6 through the shaft coupling 3, the screw rod 5, and the shaft coupling 3 in sequence, and then threadedly engages with the threaded hole of the bearing 4 through the thread of the screw rod 5 at the end. The rotation of the rotating end of the motor 2 causes the screw rod 5 at the end to rotate and move linearly in the axial direction due to the thread engagement, thereby driving the motor 2 behind to move. The two working units are placed symmetrically left and right, and the elastic material strip 7 is installed and fixed on the two bearings 6. Figure 2 As shown in , the elastic material strip 7 reciprocally winds around the two bearings 6 under the torque of the rotation of the left and right motors 2, and is straightened between the two working units. When the elastic material strip 7 is wound around the bearing 6, it is a hot area a, releases heat and rises in temperature. When the elastic material strip 7 is straightened between the two working units, it is a cold area b, absorbs heat and drops in temperature.

[0078] The strip of shape memory material 7 will be bent when it is wound on the carrier 6, which will induce the shape memory effect and release heat to the surrounding space, and the strip of shape memory material 7 will be unbent when it is unwound, which will absorb heat from the surrounding space. The carrier 6 is a cylinder, and the diameter of the cylinder determines the diameter of the circle of the bending radius of the strip of shape memory material 7. The solid-state refrigerator uses the rotation of the motor to drive the strip of shape memory material 7 to be bent on one carrier 6 and unbent on the other carrier 6, and the reverse rotation of the motor 2 can make the process reverse. The refrigeration driver is divided into two regions according to whether the temperature is higher or lower than the room temperature during operation: the hot region a and the cold region b. Specifically, the region where the strip of shape memory material is bent is the hot region a, which is the part of the two working units, and the region where the strip of shape memory material is straight is the cold region b, which is the space between the two working units. The space of the cold region b is stationary relative to the ground during the operation of the solid-state refrigerator driver. The temperature of the cold region b is lower than the room temperature, so it can be used for refrigeration.

[0079] The refrigeration driver in the example embodiment of the present disclosure and the obtained technical effects are further described below in combination with a plurality of tests.

[0080] Related tests

[0081] The structure of the refrigerator used in this test is as shown in Figure 2 The guide rail 1, shaft coupling 3, bearing 4, screw rod 5, fixed block 8 and sliding block 9 used are commercial standard parts, the carrier 6 is made of photosensitive resin by 3D printing, and the parts are connected by screws; the selected strip of shape memory material 7 is a nickel-titanium shape memory alloy plate (nickel-titanium plate) provided by Johnson Matthey Company in the United States, which is cut by a wire to have a size structure as shown in Figure 3 The two ends of the strip of shape memory material 7 are connected to the two carriers 6 by screws; the control of the motor 2 is programmed and controlled by Arduino.

[0082] The operation process of the solid-state refrigerator driver is as shown in Figure 1 (a) and Figure 1 (b), through the reciprocating rotation of the two motors 2, part of the strip of shape memory material 7 is wound and the other part is straightened, forming the hot region a and the cold region b. As Figure 4(a) As shown, the initial state of the left bearing 6 has 3 turns of the nickel-titanium shape memory alloy strip wound, the right bearing 6 has no nickel-titanium shape memory alloy strip wound, and the overall nickel-titanium shape memory alloy strip is at room temperature; as the motor rotates, the wound nickel-titanium shape memory alloy strip on the left bearing 6 unwinds, and is straightened and wound onto the right bearing under the action of the right motor; at this time, as can be seen from the infrared camera below, the straightened nickel-titanium shape memory alloy strip has a significant drop in temperature compared to the surrounding environment.

[0083] Test 1

[0084] The nickel-titanium shape memory alloy strip was installed in the solid-state refrigeration driver, and the infrared camera was used to measure the temperature change of the surface of the nickel-titanium shape memory alloy strip in the cold area between the two bearings. In the initial stage, three turns of nickel-titanium shape memory alloy strip were pre-wound on one of the bearings, and the temperature of the nickel-titanium shape memory alloy strip was room temperature (i.e. 19.80 degrees). The test began, and the motor was controlled to rotate three turns at 1.5 seconds, at which time the three turns of pre-wound nickel-titanium shape memory alloy strip on the working unit unwound and was straightened, and then the rotating shaft of the motor stopped rotating, so that the nickel-titanium shape memory alloy strip in the middle remained straight. According to the measurement results of the infrared camera, after the nickel-titanium shape memory alloy strip changed from the wound and curved state to the straightened state, the surface temperature dropped by 13.24 degrees compared to the ambient temperature, as shown in Figure 5 .

[0085] Test 2

[0086] The nickel-titanium shape memory alloy strip was installed in the solid-state refrigeration driver, and the infrared camera was used to measure the temperature change of the surface of the nickel-titanium shape memory alloy strip in the cold area between the two bearings. In the initial stage, three turns of nickel-titanium shape memory alloy strip were pre-wound on one of the bearings, and the temperature of the nickel-titanium shape memory alloy strip was room temperature (i.e. 19.80 degrees). The test began, and the motor was controlled to rotate three turns at a working frequency of 0.67 Hz, and then change the direction of rotation to rotate three turns at the same frequency, which is one cycle. The reciprocating cycle of the motor causes the nickel-titanium shape memory alloy strip to continuously move between the left and right bearings in a "winding" and "unwinding and straightening" manner. According to the measurement results of the infrared camera, after the temperature of the middle cold area reached a steady state, it remained in a periodic fluctuation state, with a peak of about 12 degrees and a trough of about 10 degrees, and the cold area could maintain an average temperature of about 11 degrees, which was 8.80 degrees lower than room temperature, as shown in Figure 6 .

[0087] Accordingly, compared with the prior art, the refrigeration driver of the present disclosure has the following advantages:

[0088] 1. Structural design: The solid-state refrigeration driver of the present disclosure realizes the bending deformation of the elastic clamping material strip under approximate pure bending conditions by controlling the diameter of the bearing design, i.e. the control curvature circle, and the degree of deformation (i.e. the elastic clamping effect) can be controlled according to the refrigeration demand. At the same time, the cold zone and the hot zone are naturally separated during the operation of the driver, and no additional heat transfer medium is needed to separate the cold and heat, greatly simplifying the system structure. Secondly, some components of the driver can be manufactured using advanced manufacturing processes such as 3D printing and slow wire cutting, which can improve the overall system accuracy and also achieve lightweight of the device. The overall driver has a volume close to that of the traditional refrigeration air conditioner.

[0089] 2. Heat transfer: The elastic clamping material in the refrigeration driver of the present disclosure adopts a strip-shaped geometric configuration, reducing the thickness and improving the heat transfer efficiency. At the same time, according to the test results, the cold zone temperature is much lower than the room temperature, meeting the refrigeration demand under room temperature conditions.

[0090] 3. Mechanics: The refrigeration driver of the present disclosure bends the elastic clamping material strip through the rotating torque of the motor, and in the example only 0.20 Nm of torque is needed to complete the winding of the elastic clamping material strip, realizing the elastic clamping effect under low driving force level. At the same time, the driver only involves rotary motion during operation, without additional mechanical transmission devices, so the overall mechanical stability is high.

[0091] In summary, the solid-state refrigeration driver and its refrigeration method of the present disclosure utilize the heat absorption and release effect of the elastic clamping material strip in reciprocating winding and bending deformation, and realize the spatial separation of the cold zone and the hot zone through mechanical structure design, reduce the driving force and the overall volume, improve the heat transfer efficiency and the stability of the driver under working conditions, and provide new possibilities for the development of lightweight elastic clamping solid-state refrigeration devices.

[0092] It can be understood that the above embodiments are only exemplary embodiments adopted to illustrate the principles of the present disclosure, but the present disclosure is not limited thereto. Various modifications and improvements can be made by those of ordinary skill in the art without departing from the spirit and essence of the present disclosure, and these modifications and improvements are also considered within the protection scope of the present disclosure.

Claims

1. A cooling actuator based on the winding and bending of a spring-loaded material, comprising at least: A pair of loads, each load arranged parallel to each other and capable of rotating along an axis, and The spring-loaded material strip has its two ends fixed to the pair of bearings. In this configuration, the pair of carriers rotates along a first direction to wrap the elastic material strip around at least one of the carriers. The portion of the elastic material strip wrapped around the carrier releases heat to form a hot zone. The pair of carriers unwraps the spring clip material strip from at least one of the carriers by rotating it in a second direction opposite to the first direction. The portion of the spring clip material strip unwrapped from the carrier absorbs heat to form a cold zone. The refrigeration driver also includes: guide, The movable end, which is slidably mounted on the guide rail, is equipped with a motor that drives the pair of load-bearing components to rotate. The fixed end is fixed to the guide rail. The carrier is rotatably connected to the fixed end, which is configured to convert the rotational motion of the carrier into linear motion of the carrier along the axis, so that the position of the cold zone relative to the guide rail remains unchanged when the refrigeration driver is running.

2. The cooling driver according to claim 1, characterized in that, In the initial state, the spring clip material strip is pre-wound onto at least one of the pair of carriers.

3. The refrigeration driver according to claim 2, characterized in that, The pair of bearings is constructed as follows: by rotating along the first direction, the elastic card material strip is wrapped around at least one of the bearings of the pair of bearings, while the pre-wrapping of the elastic card material strip on at least one of the bearings of the pair of bearings is unwrapped; then by rotating along the second direction, the elastic card material strip is wrapped and unwrapped in the opposite direction.

4. The refrigeration driver according to claim 1, characterized in that, One end of each of the pair of loads is fixedly connected to the rotating end of the motor, and the other end is fixedly connected to the screw. The fixed end has a threaded hole, and the screw engages with the threaded hole of the fixed end to convert the rotational motion of the load into the linear motion of the load along the axis.

5. The refrigeration driver according to claim 4, characterized in that, Each of the pair of carriers has a threaded groove to accommodate the spring clip material strip wound thereon. Wherein, one end of the spring clip material strip is fixed to the first end of one of the pair of carriers, and the other end of the spring clip material strip is fixed to the second end of the other of the pair of carriers opposite to the first end.

6. The cooling driver according to claim 5, characterized in that, The thread direction of the threaded grooves of each of the pair of bearings is consistent with that of each other and with that of the screw.

7. The refrigeration driver according to claim 6, characterized in that, The thread lead of the threaded groove of each of the pair of bearings is consistent with the thread lead of the screw.

8. The refrigeration driver according to claim 1, characterized in that, The spring clip material strip includes at least shape memory alloy, natural rubber, synthetic polymer, and plastic crystal.

9. The refrigeration driver according to claim 8, characterized in that, The shape memory alloy is selected from the group consisting of: nickel-titanium alloy, copper-aluminum-manganese alloy, nickel-manganese-titanium alloy, and nickel-titanium-cobalt alloy.

10. The cooling driver according to claim 1, characterized in that, The cross-section of the spring clip material strip is rectangular or circular.

11. The cooling driver according to claim 10, characterized in that, When the cross-section of the spring clip material strip is rectangular, the length of the spring clip material strip is significantly greater than its width and thickness; When the cross-section of the spring clip material strip is circular, the length of the spring clip material strip is significantly greater than the diameter of its cross-section.

12. The refrigeration driver according to claim 7, characterized in that, The thread lead of the screw, the threaded groove of the bearing, and the threaded hole of the fixed end ranges from 2.00 mm to 10.00 mm.

13. The cooling driver according to claim 1, characterized in that, The refrigeration driver also includes: A heat exchanger, which is disposed in the cold zone and / or the hot zone.

14. The cooling driver according to claim 13, characterized in that, The heat exchanger includes a fan and a duct connected to the fan for gas exchange, wherein the fan delivers air into the duct for convective heat exchange.

15. The cooling driver according to claim 13, characterized in that, The heat exchanger can be a fluid or solid heat exchanger.

16. The cooling driver according to claim 1, characterized in that, The spring clip material strip consists of multiple spring clip material strips, and the multiple spring clip material strips are disposed between the pair of carriers.

17. The refrigeration driver according to claim 16, characterized in that, The refrigeration driver further includes a hub that bundles the multiple strips of elastic card material into a parallel state.

18. The refrigeration driver according to claim 16, characterized in that, The refrigeration driver also includes multiple pairs of carriers stacked on top of each other.

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