JP7552046B2 - Heat storage material, heat storage unit, and heat storage type refrigerator, as well as heat storage material and heat storage unit - Google Patents

Description

The present invention relates to a heat storage material, a heat storage unit, a heat storage type refrigerator, a heat storage material, and a heat storage unit.

The main element of thermal cycles, such as the Stirling cycle and the Gibbord-McMahon cycle, is a regenerator. By repeating pressure and expansion at both ends of the regenerator, cold can be extracted at the expansion end of the regenerator.

Conventionally, regenerative refrigerators use a metal mesh such as stainless steel with a large specific heat as the regenerative material, punching the metal mesh into a circular shape and stacking hundreds to thousands of sheets of the metal mesh on a regenerative tube made of stainless steel or the like.

Conventionally, when metal meshes are stacked inside a regenerator tube, they are stacked one by one, and even if a jig is used for stacking, it takes a very long time, resulting in a problem of very poor productivity. In addition, hundreds to thousands of metal meshes are likely to be randomly stacked inside the regenerator tube, which may block the flow path consisting of the tiny openings of the metal mesh. Since the metal mesh is configured by weaving vertical and horizontal lines into a mesh shape, the cross section is likely to have a wavy shape, which makes it easy to stack randomly as described above and block the openings. This causes a problem of very high fluid resistance and high fluid pressure loss. Furthermore, when the metal mesh is mechanically punched into a circle, the shortened thin wires (lattice) may be missing at the circumferential end. When metal meshes with missing wires are stacked in this way, gaps are generated between the inner wall surface of the regenerator tube and the metal mesh, and the working fluid is likely to flow through the gaps. As a result, the flow rate at the center of the regenerator decreases, making it impossible to use the heat capacity effectively, resulting in a problem of reduced refrigeration efficiency. Furthermore, there is a problem of variation in refrigeration efficiency for each product.

In response to this, Patent Document 1 proposes the use of a mesh-shaped cold storage material made of three types of thin wires: a first thin wire with low thermal conductivity, a second thin wire with high specific heat, and a third thin wire that prevents metallic contact. The first thin wire of this cold storage material is wound in the axial direction into a cylindrical shape and inserted into the cylinder, improving the production efficiency of cold storage units and solving the problem of suppressing individual differences caused by mass production.

JP 2000-9356 A

However, in the configuration of Patent Document 1, because the first thin wire with low thermal conductivity is used in the axial direction of the cylinder, the flow path in the regenerator becomes narrower, resulting in a problem that the pressure loss is still large and reduces the refrigeration efficiency.

The present invention has been made in consideration of these points, and aims to provide a regenerator material, a regenerator, and a regenerator type refrigerator, as well as a heat storage material and a heat storage device, that can improve production efficiency and achieve high refrigeration efficiency with little variation.

The present invention is characterized in that the cold storage material constituting the cold storage device to be installed in a cold storage type refrigerator has a lattice-shaped lattice portion constituting the cold storage material, and a peripheral end portion which is integrally molded on the outer periphery of the lattice portion and constitutes a part of the cold storage tube, and when the cold storage material is stacked and the peripheral end portion is joined to form a part of the cold storage tube, the peripheral end portion is thicker than the lattice portion so that the lattice portions do not come into contact with each other .

In the regenerator material of the present invention, the peripheral end portion can be configured to have an outer peripheral end portion that constitutes a part of the regenerator tube, and an inner peripheral end portion that is located inside the outer peripheral end portion and constitutes a part of a pulse tube that is integrally molded with the lattice portion.

In the regenerator material of the present invention, the lattice portion has a plurality of intersecting first lattices and a plurality of intersecting second lattices, and it is preferable that the cross section of the first lattice and the second lattice in the thickness direction has a maximum width at the center of the thickness direction, and the width decreases from the center of the thickness direction in the vertical direction.

In the regenerator material of the present invention, it is preferable that a recess is formed between the lattice portion and the peripheral end portion.

The regenerator of the present invention is a regenerator to be mounted in a regenerator-type refrigerator, characterized in that multiple regenerator materials described above are stacked and bonded together.

In the regenerator of the present invention, it is preferable that each regenerator material is stacked at the peripheral end position via a spacer having approximately the same width as the peripheral end.

In the regenerator of the present invention, it is preferable that the regenerator materials are rotated and stacked so that the meshes of the lattice portions of the regenerator materials adjacent to each other in the stacking direction are not aligned.

In the regenerator of the present invention, a regenerator material unit in which a plurality of the regenerator materials are joined and integrated can be configured by stacking a plurality of the regenerator materials.

The regenerator of the present invention is a regenerator to be mounted on a regenerator type refrigerator, and is characterized in that it has a regenerator tube and a lattice-shaped lattice portion constituting a regenerator material , and a plurality of the lattice portions are molded integrally with the regenerator tube inside the regenerator tube, spaced apart so as not to come into contact with each other.

In the regenerator of the present invention, it is preferable that the outer surface of the outer end portion constituting the regenerator tube is mirror-finished.

The regenerative refrigerator of the present invention is characterized by being equipped with the regenerator described above.

The present invention is characterized in that the heat storage material constituting the heat storage device has a lattice-shaped lattice portion constituting the heat storage material, and a peripheral end portion that is integrally molded on the outer periphery of the lattice portion and constitutes a part of the heat storage tube, and when the heat storage material is stacked and the peripheral end portion is joined to form a part of the heat storage tube, the peripheral end portion is thicker than the lattice portion so that the lattice portions do not come into contact with each other .

The heat storage device of the present invention is characterized in that the heat storage material is laminated and bonded to each other.

According to the present invention, the cold storage unit is constructed by stacking and joining multiple cold storage materials, each of which is made by integrally forming a lattice-shaped lattice portion constituting the cold storage material and a peripheral end portion constituting a part of the cold storage tube. This makes it possible to improve production efficiency and obtain high refrigeration efficiency with little variation.

FIG. 1 is a diagram showing the configuration of a Stirling type pulse tube refrigerator. FIG. 2 is a diagram showing the principle of the heat cycle of a Stirling type pulse tube refrigerator. FIG. 3 is a diagram showing the configuration of a conventional regenerator. FIG. 4A is a plan view of the regenerator material according to this embodiment, and FIG. 4B is a partially enlarged plan view of the regenerator material shown in FIG. 4A. FIG. 5A is a plan view of the regenerator material according to this embodiment, and FIG. 5B is a cross-sectional view taken along line AA shown in FIG. 5A. FIG. 6A is a plan view of a regenerator material according to another embodiment, and FIG. 6B is a cross-sectional view taken along line BB shown in FIG. 6A. FIG. 7A is a partially enlarged plan view of a lattice portion of the regenerator material according to this embodiment, and FIG. 7B is an enlarged cross-sectional view of the vertical lattice taken along line CC shown in FIG. 7A. FIG. 8A is a plan view of a regenerator material according to another embodiment, and FIG. 8B is a cross-sectional view taken along line D-D shown in FIG. 8A, and also shows an enlarged cross-sectional view of the portion surrounded by the dotted line in FIG. 8B. FIG. 9 is an exploded perspective view of a regenerator formed by laminating and bonding a plurality of regenerator materials according to this embodiment. FIG. 10A shows the stacked state when the lattice portions of the regenerator materials are stacked with the mesh aligned, and FIG. 10B is an exploded oblique view showing the stacked state when the lattice portions of the regenerator materials are stacked with the mesh not aligned. Figure 11A is a plan view of a regenerator material for this embodiment and a cross-sectional view of the regenerator material cut along line E-E, and Figure 11B is a plan view of a spacer for this embodiment and a cross-sectional view of the spacer cut along line F-F. FIG. 12A is a graph showing the relationship between the porosity of the regenerator and the refrigeration efficiency, and FIG. 12B is a graph showing the relationship between the porosity of the regenerator and the pressure loss.

Hereinafter, the cold storage material, cold storage unit, and cold storage type refrigerator according to the embodiment of the present invention will be described in detail with reference to the attached drawings. Note that the cold storage material, cold storage unit, and cold storage type refrigerator according to the present invention are not limited to the following embodiment, and can be modified in various ways within the scope of the spirit of the invention. First, the configuration of the cold storage material and the cold storage type refrigerator equipped with the cold storage unit according to the present embodiment will be described.

<Regenerative refrigerator>
1 is a diagram showing the configuration of a Stirling pulse-tube refrigerator. A Stirling pulse-tube refrigerator 100 according to this embodiment includes a compressor 101, a copper heat exchanger (aftercooler) 103, a regenerator 104, a copper heat exchanger (low temperature end) 105, a pulse tube 106, a copper heat exchanger (high temperature end) 109, an inertance tube 107, and a reservoir 108.

As shown in FIG. 1, the compressor 101 has an expansion piston 102 inside. The expansion piston 102 generates a pressure wave by reciprocating (e.g., 50 Hz) with a linear motor (not shown).

The compressor 101 is connected to the regenerator 104, and the end of the regenerator 104 on the compressor side is equipped with a copper heat exchanger (aftercooler) 103. On the other hand, the end of the regenerator 104 opposite the compressor is connected to a stainless steel pulse tube 106, and a copper heat exchanger (low temperature end) 105 is provided between the regenerator 104 and the pulse tube 106.

The pressure wave generated by the expansion piston 102 is dissipated in a copper heat exchanger (aftercooler) 103 for dissipating the heat of compression, passes through a regenerator 104, passes through a copper heat exchanger (low temperature end) 105 which serves as a cooling section, and flows into a pulse tube 106 (e.g., made of stainless steel).

The pulse tube 106 is equipped with a copper heat exchanger (high temperature end) 109 at the end opposite the compressor. In addition, the pulse tube 106 is connected to an inertance tube 107 (e.g., stainless steel) with an inner diameter of about several mm at the end opposite the compressor. The inertance tube 107 is then connected to a reservoir 108 (e.g., stainless steel) with a volume of about 100 cc.

The length from the inertance tube 107 to the reservoir 108 is adjusted so that the working gas inside the pulse tube 106 behaves in a similar manner to the expansion piston 102 of the Stirling pulse tube refrigerator 100.

The copper heat exchanger (low temperature end) 105, which is extremely cold, for example at about 70K, is installed in the vacuum vessel 110, including the regenerator 104 and the pulse tube 106, to prevent heat from entering from the outside. Furthermore, to improve the thermal insulation against radiation, a multi-layer insulation material (not shown) such as super insulation may be installed.

In addition, the inner surface of the vacuum vessel 110, the outer surface of the regenerator 104, and the outer surface of the pulse tube 106 are mirror-finished to reduce surface roughness in order to suppress radiation.

<Thermal cycle principle>
Using FIG. 2, the principle of the heat cycle and the configuration of a general regenerator will be explained using a Stirling pulse tube refrigerator as an example.

The left diagram of Figure 2 illustrates the principle of the heat cycle of a Stirling refrigerator. Starting from the initial state (1), in the compression stroke, the working gas compressed by the compression piston dissipates heat in the aftercooler (state (2)). Next, in the constant volume stroke, the working gas passes through the regenerator filled with regenerator material and flows into the space on the expander side (state (3)). Then, in the expansion stroke, the working gas expands on the expander side by the expansion piston and cools the low-temperature end (state (4)). In the constant volume stroke, the cooled working gas passes through the regenerator in the opposite direction to the compression stroke, returning to the initial state (1) before the first compression. At this time, the working gas passes through the regenerator while exchanging heat, and gradually returns to its initial temperature. By repeating this operation, cold energy in the extremely low temperature range can be obtained. The refrigeration efficiency (COP) in the thermal cycle can be calculated by the formula COP = _Tc / ( _Th - _Tc ), where _Th is the aftercooler temperature and Tc is the low temperature end temperature. As shown in the right diagram of Fig. 2 (vertical: pressure P, horizontal: volume _V ), the aftercooler on the compressor side is always kept at a constant temperature (e.g., 300K (Kelvin)), while the temperature at the low temperature end on the expander side drops each time the cycle is repeated, and it is possible to cool to a temperature that balances the heat intrusion from the surroundings and the regenerator and the amount of cold heat from expansion.

<Problems with the related art and overview of this embodiment>
Fig. 3 shows a simplified structure of a conventional regenerator used in regenerative refrigerators with a liquid nitrogen temperature of 77 K. A metal mesh such as stainless steel with a large specific heat is used as the regenerator material, which is punched into a circular shape and several hundred to several thousand sheets are stacked inside a cylindrical regenerator tube.

As shown in Figure 3, in a configuration in which multiple metal meshes are stacked inside the regenerator, the production efficiency of the regenerator deteriorates, the stacked state of the metal mesh inside the regenerator tube is unstable, and defects such as the mesh holes of the metal mesh being blocked or gaps being formed between the metal mesh and the regenerator tube tend to occur inside, resulting in problems such as variations in cooling efficiency between products and reduced cooling efficiency.

Therefore, the inventors constructed a cold storage device by stacking and joining multiple cold storage materials, each of which is made by integrally forming a lattice-shaped lattice portion that constitutes the cold storage material and an outer peripheral end portion that constitutes part of the cold storage tube. This makes it possible to improve the production efficiency of cold storage devices, reduce the variation in refrigeration efficiency between products, and achieve high refrigeration efficiency.

<Cool storage material>
A regenerator material used in manufacturing the regenerator will be described. Fig. 4A is a plan view of the regenerator material according to this embodiment, and Fig. 4B is a partially enlarged plan view of the regenerator material shown in Fig. 4A. The regenerator material according to this embodiment is preferably formed using stainless steel, which has a large specific heat and excellent workability even in that temperature range, assuming a regenerator type refrigerator targeted at the liquid nitrogen temperature level.

As shown in FIG. 4A, the regenerator material 1 includes a lattice-shaped lattice portion 2 that constitutes the regenerator material, and an outer peripheral end portion 3 that is integrally molded on the outer periphery of the lattice portion 2 and constitutes a part of the regenerator tube. There is no limitation on the method for integrally molding the lattice portion 2 and the outer peripheral end portion 3, but for example, they can be formed by processing a metal plate with etching or a laser.

As shown in Figures 4A and 4B, the lattice section 2 is formed by a lattice pattern consisting of multiple vertical lattices (first lattice) 2a that extend linearly in the Y direction and are spaced at regular intervals in the X direction perpendicular to the Y direction, and multiple horizontal lattices (second lattice) 2b that extend linearly in the X direction and are spaced at regular intervals in the Y direction. For this reason, in this embodiment, the openings 2c (lattice meshes) formed by the intersection of the vertical lattices 2a and the horizontal lattice 2b are formed in a quadrilateral (square) shape. However, the shape of the openings 2c is not particularly limited, and the lattice section 2 may be configured to have, for example, a honeycomb structure.

The outer peripheral end 3, which is molded integrally with the outer periphery of the lattice portion 2, is preferably circular. However, since the outer peripheral end 3 is a portion in which multiple regenerator materials 1 are stacked to form the outer peripheral surface of the regenerator tube, the shape of the outer peripheral end 3 can be determined according to the required outer peripheral surface shape of the regenerator.

Although not limited thereto, it is desirable that the width W of the lattice portion 2 is on the order of several μm to several tens of μm, and the opening width D is on the order of several tens of μm. It is also desirable that the diameter (outer diameter) d of the outer peripheral end portion 3 is on the order of several tens of mm. It is also desirable that the width L of the outer peripheral end portion 3 is small, since the larger the width L, the greater the heat loss due to thermal conduction in the stacking direction. For example, it is desirable that the width L of the outer peripheral end portion 3 is on the order of sub-mm, since it needs to be strong enough to withstand the pressure of the working gas inside.

In this embodiment, as shown in FIG. 5B, it is preferable that the regenerator material 1 is formed so that the thickness T1 of the outer peripheral end 3 is thicker than the thickness T0 of the lattice portion 2. This makes it possible to configure the lattice portions 2 not to come into contact with each other when a regenerator is manufactured by stacking a plurality of regenerator materials 1. Note that a separate member may be disposed at the position of the outer peripheral end 3 so as to have a thickness T1, or the outer peripheral end 3 having a thickness T1 may be integrally formed.

Figure 6A is a plan view of a regenerator material according to another embodiment, and Figure 6B is a cross-sectional view taken along line B-B shown in Figure 6A.

In the regenerator material 1 shown in FIG. 6A, an inner peripheral end 6 that constitutes part of a pulse tube is provided inside the outer peripheral end 3, and the lattice portion 2, the outer peripheral end 3, and the inner peripheral end 6 are integrally molded. A coaxial return type regenerator can be constructed by stacking and joining multiple regenerator materials 1 shown in FIG. 6A.

As for the thickness of each part of the regenerator material 1 shown in FIG. 6B, it is preferable that the thickness T1 of the outer peripheral end 3 and the thickness T3 of the inner peripheral end 6 are thicker than the thickness T0 of the lattice part 2. It is preferable that the thickness T1 of the outer peripheral end 3 and the thickness T3 of the inner peripheral end 6 are the same thickness.

Figure 7A is a partially enlarged plan view of the lattice portion of the regenerator material according to this embodiment, and Figure 7B is an enlarged cross-sectional view of the vertical lattice cut along line C-C shown in Figure 7A.

As shown in FIG. 7A, the lattice section 2 has a plurality of intersecting vertical lattices (first lattices) 2a and a plurality of intersecting horizontal lattices (second lattices) 2b, and the cross section in the thickness direction of each of the lattices 2a and 2b has, for example, the cross-sectional shape shown in FIG. 7B.

In FIG. 7B(a), the thickness cross section is rectangular, and the width W1 of the thickness central portion O1 and the width from the thickness central portion O1 in the vertical direction are approximately constant. In contrast, in FIG. 7B(b), the thickness cross section is circular, and in FIG. 7B(c), the thickness cross section is rhombic. In these, the widths W2 and W3 of the thickness central portion O1 are the largest, and the widths gradually decrease from the thickness central portion O1 in the vertical direction. As shown in FIG. 7B(b) and (c), by controlling the cross-sectional shape of the thickness direction of the lattices 2a and 2b so that the width of the thickness central portion O1 is the largest, the entire surface area of the lattices 2a and 2b can be used more effectively as a heat transfer surface. The cross-sectional shape is not particularly limited, and may be a hexagon or other shape.

The embodiment shown in FIG. 7 can be applied to each of the embodiments shown in FIG. 4 to FIG. 6.

Figure 8A is a plan view of a regenerator material according to another embodiment, and Figure 8B is a cross-sectional view taken along line D-D in Figure 8A, along with an enlarged cross-sectional view of the area enclosed by the dotted line in Figure 8B.

As shown in FIG. 8B, it is preferable to provide a recess 7 at the boundary between the lattice portion 2 and the outer peripheral end 3. This allows a thin-walled portion that is thinner than the lattice portion 2 and the outer peripheral end 3 to be formed between the lattice portion 2 and the outer peripheral end 3. Therefore, the outer peripheral end 3, which becomes the cold storage tube (cylindrical portion) of the cold storage unit, and the lattice portion 2 can be thermally separated, and when multiple cold storage unit materials 1 of this embodiment are stacked, the inflow of heat through the outer peripheral end 3, which becomes the cylindrical portion, can be effectively suppressed.

The embodiment shown in FIG. 8 can be applied to each of the embodiments shown in FIG. 4 to FIG. 7. That is, in a configuration having an outer peripheral end 3 and an inner peripheral end 6 as shown in FIG. 6, it is preferable to provide a recess 7 between the inner peripheral end 6 and the lattice portion 2 as well.

<Cool storage unit>
FIG. 9 is an exploded perspective view of a regenerator formed by stacking and bonding a plurality of regenerator materials of the present embodiment. As shown in FIG. 9, a regenerator 10 in which a regenerator tube and a plurality of lattice-shaped regenerator materials built in the regenerator tube are integrated can be manufactured by stacking a plurality of regenerator materials 1 of the present embodiment and bonding the outer peripheral end 3 of each regenerator material 1. For example, the outer peripheral end 3 can be bonded by diffusion bonding or the like. In this way, the regenerator 10 can be formed by a simple process of stacking and bonding a plurality of regenerator materials 1, and production efficiency can be improved. In addition, in this embodiment, the vertical lattice 2a and the horizontal lattice 2b constituting the lattice portion 2 are integrally formed. Therefore, unlike the conventional metal mesh in which metal wires are woven, the lattice portion 2 can be formed in a planar shape. Therefore, in the regenerator 10 of this embodiment, when a plurality of regenerator materials 1 are stacked, the flow path of the regenerator material (lattice portion 2) is not blocked, and pressure loss can be suppressed. In addition, in this embodiment, since the cold storage material and the cold storage tube are integrally molded, the problem of a gap occurring between the cold storage material and the cold storage tube does not occur, and the interval between the stacked cold storage materials can be kept constant, thereby suppressing the variation in cooling efficiency between products and achieving high refrigeration efficiency.

Figure 10A shows a stacked state when the lattice portions of the regenerator materials are aligned, and Figure 10B is a perspective view showing a stacked state when the lattice portions of the regenerator materials are not aligned. In Figure 10A, when multiple regenerator materials 1 are stacked, the lattice directions are aligned so that the lattice portions 2 of adjacent regenerator materials 1 are aligned (in-line type). The lattice direction in Figure 10A is the XY direction. In Figure 10A, the lattice directions of the lattice portions 2 of all regenerator materials 1 are aligned in the XY direction. On the other hand, in Figure 10B, when multiple regenerator materials 1 are stacked, the regenerator materials 1 are rotated so that the lattice portions 2 of adjacent regenerator materials 1 in the stacking direction are not aligned (staggered type). In FIG. 10B, the lattice direction of the bottom regenerator material 1 and the top regenerator material 1 is the XY direction, but the lattice direction of the middle regenerator material 1 is rotated by 45 degrees. By stacking adjacent regenerator materials 1 in the stacking direction at different rotation angles in this way, the meshes of the lattice parts 2 of the adjacent regenerator materials 1 become uneven. In this way, in a regenerator with uneven meshes of the lattice parts 2, turbulence can be promoted and thermal conduction can be improved.

Figure 11A is a plan view of the regenerator material according to this embodiment and a cross-sectional view of the regenerator material cut along line E-E, and Figure 11B is a plan view of the spacer according to this embodiment and a cross-sectional view of the spacer cut along line F-F.

As shown in FIG. 11A, the thickness of the lattice portion 2 and the outer peripheral end 3 constituting the cold storage material 1 are the same as T1, but when multiple cold storage materials 1 are stacked and joined, the cold storage material 1 and the ring-shaped spacer 4 shown in FIG. 11B are alternately stacked to form a configuration in which the lattice portions 2 of the stacked cold storage materials 1 do not come into contact with each other. The spacer 4 is ring-shaped with the same width as the outer peripheral end 3, and by separately forming the spacer 4 in this way and sandwiching it between each cold storage material 1, a cold storage material in which the cold storage material 1 and the spacer 4 are alternately stacked can be manufactured. Although not shown, in a configuration in which the inner peripheral end 6 is provided as in FIG. 6A and the outer peripheral end 3 and the inner peripheral end 6 are formed with the same thickness T1 as the lattice portion 2, it is preferable to sandwich a ring-shaped spacer 4 approximately equal to the width of the outer peripheral end 3 and a ring-shaped spacer approximately equal to the width of the inner peripheral end 6 between the stacked cold storage materials 1. This reinforces the inner peripheral end 6 side, and more effectively prevents the lattice parts 2 of the stacked regenerator materials 1 from coming into contact. In this case, it is preferable that the thickness T2 of the spacer 4 facing the outer peripheral end 3 and the spacer facing the inner peripheral end 6 are both formed to the same thickness.

As described above, in order to prevent the lattice portions 2 of the stacked regenerator materials 1 from contacting each other, the regenerator materials 1 may be stacked with the outer peripheral end 3 and inner peripheral end 6 formed to be thicker than the lattice portions 2 as shown in Figures 5 and 6, or a spacer 4 may be sandwiched between the regenerator materials 1 as shown in Figure 11. In this way, a regenerator configured so that the lattice portions 2 of the regenerator materials 1 do not contact each other can further increase the refrigeration efficiency.

When stacking multiple regenerator materials 1, the cooling efficiency can be increased more effectively by manufacturing a regenerator using a regenerator material 1 having a configuration in which the lattices 2a and 2b have the cross-sectional shape shown in Figures 7B (b) and (c), or a configuration in which a recess 7 is formed between the lattice portion 2 and the outer peripheral end portion 3 as shown in Figure 8.

The outer peripheral surface of the regenerator 10 is also mirror-finished to reduce surface roughness. For example, after the regenerator 10 of this embodiment is integrally molded, it is desirable to polish the outer peripheral surface to a mirror finish. Any existing polishing process can be used. This can suppress radiation.

The regenerator 10 may also be configured by preparing a regenerator material unit in which multiple regenerator materials 1 listed above are joined together and integrated, and then stacking and joining the multiple regenerator material units.

Alternatively, the regenerator 10 may be configured such that the lattice-shaped lattice sections 2 constituting the regenerator material, which are stacked in multiple layers, and the outer peripheral end section 3 constituting the regenerator tube, which connects the outer periphery of each lattice section, are integrally molded. For example, a 3D printer can be used to mold the final shape in which the multiple lattice sections 2 and the outer peripheral end section 3 constituting the regenerator tube are integrated. Note that even in a configuration that includes an inner peripheral end section constituting a pulse tube, the final shape in which the multiple lattice sections 2, the outer peripheral end section constituting the regenerator tube, and the inner peripheral end section constituting the pulse tube are integrated can be molded, for example, by a 3D printer.

Although the regenerator material and regenerator used in the regenerator type refrigerator have been described above, a heat storage material and a heat storage device using the same can be configured with the same configuration as the regenerator material described above. For example, the heat storage material of this embodiment is characterized by having a lattice-shaped lattice portion that constitutes the heat storage material, and a peripheral end portion that is integrally molded on the outer periphery of the lattice portion and constitutes a part of the heat storage tube. In addition, a heat storage device can be formed by stacking multiple heat storage materials and joining them together. For example, by using it as a heat storage device for a prime mover, an efficiency improvement effect can be obtained. The structures of each embodiment described for the regenerator material and regenerator can be applied to the heat storage material and the heat storage device.

The effects of the present invention will be explained below using examples of the present invention. Note that the present invention is not limited in any way by the following examples.

In the experiment, the lattice width W (see Figure 4) and the porosity of the regenerator were changed in a pulse tube refrigerator, and the refrigeration efficiency COP (refrigeration output/compression work) and pressure loss of the regenerator were measured. The experimental results are shown in Figure 12.

As shown in FIG. 12A, the refrigeration efficiency peaks at a certain porosity for each width W. In addition, in this experimental example, the width W itself also peaked at 10 μm (near a porosity of 85%), and it was found that performance can be improved by adjusting the width W and porosity. This corresponds to a trade-off between the heat capacity and pressure loss as a cold storage material.

As shown in FIG. 12B, it was found that at low porosity (a region where there is sufficient heat capacity in a certain temperature range), pressure loss increases and refrigeration efficiency decreases. On the other hand, at high porosity, pressure loss decreases, but heat capacity is insufficient and refrigeration efficiency decreases. Therefore, in the regenerator of this embodiment, the desired width and porosity can be obtained by adjusting the lattice portion (width W, opening width D) and the stacking interval, making it possible to improve refrigeration efficiency.

The regenerator material, regenerator, and regenerator-type refrigerator using these of the present invention improve the production efficiency of the regenerator by integrally molding the regenerator material and the regenerator tube, and ensure high refrigeration efficiency with little variation. As a result, it is possible to easily manufacture regenerators with excellent refrigeration efficiency, and they are suitable for mass production.

1: Regenerator material 2: Lattice portion 2a: Vertical lattice (first lattice)
2b: Horizontal lattice (second lattice)
2c: Opening 3: Outer peripheral end 4: Spacer 6: Inner peripheral end 7: Recess 10, 104: Regenerator 100: Stirling type pulse tube refrigerator 101: Compressor 102: Expansion piston 103: Copper heat exchanger (aftercooler)
105: Copper heat exchanger (low temperature end)
106: Pulse tube 107: Inertance tube 108: Reservoir 109: Copper heat exchanger (high temperature end)
110: Vacuum vessel d: Diameter of outer peripheral end D: Opening width L: Width of outer peripheral end W: Width of lattice part W1, W2, W3: Width of center part O1 in thickness direction O1: Center part T0 in thickness direction: Thickness of lattice part T1: Thickness of outer peripheral end T2: Thickness of spacer T3: Thickness of inner peripheral end

Claims (13)

In a regenerator material constituting a regenerator mounted in a regenerator type refrigerator,
The regenerator tube has a lattice-shaped lattice portion that constitutes a regenerator material, and a peripheral end portion that is integrally formed on an outer periphery of the lattice portion and constitutes a part of the regenerator tube,
The regenerator material is characterized in that, when the regenerator materials are stacked and the peripheral ends are joined to form a part of the regenerator tube, the peripheral ends are thicker than the lattice portions so that the lattice portions do not come into contact with each other. The regenerator material according to claim 1, characterized in that the peripheral end portion has an outer peripheral end portion that constitutes a part of the regenerator tube, and an inner peripheral end portion that is located inside the outer peripheral end portion and constitutes a part of a pulse tube that is integrally molded with the lattice portion. The regenerator material according to claim 1 or 2, characterized in that the lattice portion includes a plurality of intersecting first lattices and a plurality of intersecting second lattices, and the cross section of the first lattice and the second lattice in the thickness direction has the largest width at the center in the thickness direction, and the width decreases from the center in the thickness direction in the vertical direction. The regenerator material according to any one of claims 1 to 3, characterized in that a recess is formed between the lattice portion and the peripheral end portion. In a regenerator mounted in a regenerator type refrigerator,
A regenerator comprising a plurality of regenerator materials according to any one of claims 1 to 4 stacked and bonded to each other. The regenerator according to claim 5, characterized in that each regenerator material is stacked at the peripheral end position via a spacer having approximately the same width as the peripheral end. The regenerator according to claim 5 or 6, characterized in that the regenerator materials are rotated and stacked so that the meshes of the lattice portions of the regenerator materials adjacent to each other in the stacking direction are not aligned. The regenerator according to any one of claims 5 to 7, characterized in that a plurality of regenerator material units in which a plurality of the regenerator materials are joined and integrated are stacked. In a regenerator mounted in a regenerator type refrigerator,
The present invention has a regenerator tube and a lattice-shaped lattice portion that constitutes a regenerator material,
A regenerator , characterized in that a plurality of the lattice portions are molded integrally with the regenerator tube inside the regenerator tube at intervals so as not to contact each other. 10. The regenerator according to claim 5, wherein an outer peripheral surface of the regenerator tube is mirror-finished. A regenerative refrigerator equipped with a regenerator according to any one of claims 5 to 10. In the heat storage material constituting the heat storage device,
The heat storage tube has a lattice-shaped lattice portion that constitutes a heat storage material, and a peripheral end portion that is integrally formed on an outer periphery of the lattice portion and constitutes a part of the heat storage tube,
The heat storage material is characterized in that, when the heat storage material is stacked and the peripheral ends are joined to form a part of the heat storage tube, the peripheral ends are thicker than the lattice portions so that the lattice portions do not come into contact with each other. A heat storage device comprising a plurality of heat storage materials according to claim 12, laminated and joined together.

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