Freezer

Abstract

To provide a liquid freezer capable of freezing a product efficiently with a compact configuration, and suitably used in quick freezing at production sites and supermarkets.SOLUTION: A water tank 4 for freezing a product is arranged in a water tank frame 2 in an upper stage of a machine frame 1, and a freezing device that circulates and supplies brine solution to the water tank 4 is installed in a machine room frame 5 in a lower stage of the machine frame 1. The freezing deice comprises: a Stirling freezer 7; a brine circulation pump 10 that moves the brine solution in and out of an inner cylinder 9 surrounding a cooling head 8 of the Stirling freezer 7, and moves the brine solution in and out of the water tank 4; and a radiator 11 that cools the Stirling freezer 7.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a refrigerator, and more particularly to a refrigerator that has a compact configuration and is capable of efficiently freezing products. [Background technology]

[0002] Freezing is essential for maintaining the quality and long-term storage of food. Food contains a large amount of water inside, so it can be frozen by placing it at low temperatures, but if the freezing process proceeds slowly, the cell membranes will be destroyed and the water will turn into large pieces of ice outside the cells, resulting in a deterioration in quality. Therefore, the freezing process must be carried out as quickly as possible.

[0003] Known quick freezing methods include an air-cooling freezing method in which cold air from a refrigerator is directly applied to the food, a contact freezing method in which the food is placed on a cold metal plate, a liquid freezing freezing method in which the food is immersed in a low-temperature antifreeze and frozen, and a liquefied gas freezing method that utilizes the latent heat of vaporization of a low-temperature liquefied gas such as nitrogen, etc. Of these freezing methods, the refrigerator of the present invention uses the liquid freezing freezing method, which has better surface heat transfer power than the air method and can shorten the freezing time.

[0004] Conventional general liquid refrigerators are of the compressor type, but since it is difficult to obtain a temperature below -20°C using a small compressor, a large compressor is required. This makes the entire device larger, requiring more space for installation, and consuming more power.

[0005] There has been a proposal to use a Stirling refrigerator as a refrigerator (JP Patent Publication 2004-286368 A). The Stirling refrigerator proposed in this proposal is characterized by a radiator for a cooling water device that exchanges heat between the working gas of the Stirling refrigerator and a refrigerant for heat dissipation, but it has a complicated configuration and cannot meet the demand for compactness and simplification intended in the present invention. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2004-286368 A Summary of the Invention [Problem to be solved by the invention]

[0007] In the case of a refrigerator using the Stirling refrigerator proposed above, the structure is complicated and it is not possible to meet the demand for compactness and simplification intended by the present invention.

[0008] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a liquid freezer that is compact and simply configured, can efficiently freeze products, can be easily installed in production areas, supermarkets, etc., and is suitable for use for on-site quick freezing. [Means for solving the problem]

[0009] The invention described in claim 1 for solving the above problem comprises a water tank for freezing products installed in a water tank frame in the upper stage of the machine frame, and a refrigeration device for circulating and supplying a brine solution to the water tank installed in a machine room frame in the lower stage of the machine frame, The refrigeration equipment is a liquid refrigerator characterized by including a Stirling refrigerator, a brine circulating pump that moves a brine solution in and out of an inner cylinder surrounding a cooling head of the Stirling refrigerator and also moves the brine solution in and out of the water tank, and a radiator for cooling the Stirling refrigerator.

[0010] In one embodiment, the cooling water of the radiator flows through a water jacket formed in the Stirling refrigerator to cool the Stirling refrigerator. In one embodiment, the cooling fan of the radiator is controlled to start rotating when the temperature of the cooling water rises to a predetermined temperature and to stop rotating when the temperature falls to the predetermined temperature.

[0011] In one embodiment, the water tank is fitted with a sealing lid that is opened and closed to allow products to be inserted or removed.

[0012] In one embodiment, the inner cylinder of the Stirling refrigerator is surrounded by an outer cylinder which is a vacuum insulation chamber.

[0013] In one embodiment, a spray nozzle is attached to the outlet of a discharge pipe connected to the water tank. Effect of the Invention

[0014] The liquid freezer of the present invention is as described above. It has a compact and simple configuration and can efficiently freeze products. It can be easily installed in production areas, supermarkets, etc., and is suitable for use for quick freezing on the spot. [Brief description of the drawings]

[0015] [Figure 1] 1 is a front view of an embodiment of a liquid refrigerator according to the present invention; [Diagram 2] 1 is a partial cutaway side view of one embodiment of a liquid refrigerator according to the present invention; [Diagram 3] 1 is a plan view of one embodiment of a liquid refrigerator according to the present invention; [Figure 4] FIG. 2 is a view taken along the line AA in FIG. [Diagram 5] FIG. 1 is a front view showing a configuration of a Stirling refrigerator used in a liquid refrigerator according to the present invention. [Figure 6] FIG. 2 is a side view showing the configuration of a Stirling refrigerator used in the liquid refrigerator according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The embodiment of the present invention will be described in detail with reference to the accompanying drawings. The refrigerator according to the present invention comprises a product freezing water tank 4 surrounded by a heat insulating material 3 and supported by a water tank frame 4a in a water tank frame 2 in the upper stage of a machine frame 1, and a refrigeration device for circulating and supplying a brine solution to the water tank 4 in a machine room frame 5 in the lower stage of the machine frame 1. The refrigeration device includes a Stirling refrigerator 7, a brine circulation pump 10 for feeding the brine solution into and out of an inner cylinder 9 surrounding a cooling head 8 of the Stirling refrigerator 7 and feeding the brine solution into and out of the water tank 4, and a radiator 11 for cooling the Stirling refrigerator 7 (see Figs. 1 and 2). The side of the machine room frame 5 is covered with, for example, a punched metal.

[0017] A sealing lid 12, which opens and closes the water tub 4 when putting products in and taking them out, is attached to the top surface of the water tub frame 2 via a hinge 13. A handle 14 is attached to the sealing lid 12, which is held to open and close the lid.

[0018] The water tank 4 is supplied with the brine solution cooled in the Stirling refrigerator 7 by the action of the brine circulation pump 10. That is, a discharge pipe 16 is extended from the machine room frame 5 through the heat insulating material 3, and a discharge jet nozzle 18 for increasing the discharge pressure is provided at the opening end that opens to the upper side of the water tank 4. Preferably, the end of the discharge pipe 16 is branched into two, and a discharge jet nozzle 18 is provided at each opening end (see Figs. 1 and 3). A suction port 17a is provided at the bottom of the water tank 4 (Fig. 1) to which a suction pipe 17 for returning the brine solution in the water tank 4 to the Stirling refrigerator 7 is connected. Also, a drain pipe 19 for draining the brine solution is provided at the bottom of the water tank 4.

[0019] Stirling refrigerator 7 is fixed to a support 20 attached to the inner bottom surface of machine room frame 5, with a drain pan 31 placed underneath. An operation switch panel 32 and an electrical component storage box 33 are also provided on the inner surface of machine room frame 5 (see Fig. 4). An adjuster bolt 34 is attached to the bottom surface of machine room frame 5, allowing the machine frame 1 to be adjusted for balance.

[0020] Stirling refrigerator 7 comprises refrigerator body 21, cooling head 8, and head cover 22 surrounding cooling head 8 (see especially Figures 5 and 6). Head cover 22 is a heat exchange chamber facing cooling head 8 and comprises inner cylinder 9 filled with brine solution, and outer cylinder 15 which is a vacuum insulation chamber surrounding inner cylinder 9. Upper and lower lids 36, 36a of outer cylinder 15 are connected by bolts 37.

[0021] The inner cylinder 9 has a discharge pipe connection port 41 connected to a discharge pipe 16 extending to the water tank 4, and a suction pipe 17 extending from the brine circulating pump 10 connected to a suction pipe connection port 42. A spray nozzle 43 is provided at the suction pipe connection port 42, and a flow is generated in the inner cylinder 9 by the brine solution sprayed from the spray nozzle 43.

[0022] The brine solution is usually an alcohol-brine solution, and is circulated in the brine solution passage by the action of the brine circulating pump 10. The brine circulating pump 10 has a pump discharge port 45 and a pump suction port 46. A discharge pipe 16a extending to the inner cylinder 9 is connected to the pump discharge port 45, and a suction pipe 17 extending from the water tank 4 is connected to the pump suction port 46 (see FIG. 2 in particular).

[0023] In this configuration, when the brine circulating pump 10 operates, the brine solution in the water tank 4 is drawn into the brine circulating pump 10 from the pump suction port 46 through the suction pipe 17, and flows out from the pump discharge port 45 to the discharge pipe 16a. The brine solution is then cooled through the Stirling refrigerator 7, and is returned to the water tank 4 through the discharge pipe 16.

[0024] In the above circulation process, the brine solution passes through the suction pipe connection port 42 to which the suction pipe 17 is connected, and is sprayed from the spray nozzle 43 into the inner cylinder 9, where it is re-cooled by the cooling head 8. The re-cooled brine solution flows out of the discharge pipe connection port 41 of the inner cylinder 9 into the discharge pipe 16 by the action of the brine circulation pump 10, circulates through the discharge pipe 16, and is sprayed into the water tank 4 from the spray nozzle 18 at the open end facing the water tank 4, causing a flow in the water tank 4 and cooling the stored brine solution. To increase the efficiency of removing heat from the surface of the food, it is necessary to increase the heat transfer coefficient, and this flow of the solution contributes to increasing the heat transfer coefficient.

[0025] The brine solution discharged from the suction port 17a of the water tank 4 to the suction pipe 17 is returned to the inner cylinder 9 of the Stirling refrigerator 7 via the brine circulation pump 10 and is re-cooled.

[0026] Stirling refrigerator 7 has a low temperature section and a high temperature section which are separate from each other, but since the present invention does not utilize the high temperature section, it is necessary to cool it. For this purpose, radiator 11 is used in the present invention.

[0027] Radiator 11 circulates cooling water (antifreeze) to cool Stirling refrigerator 7, and the cooling water cooled by the cooling fan is supplied from outlet hose 52 by the action of cooling water circulation pump 51, flows into a water jacket from inlet connection port 53 of the water jacket provided in refrigerator body 21 of Stirling refrigerator 7, and flows out from outlet connection port 54 on the opposite side into inlet hose 55, and is returned to radiator 11. The cooling fan of radiator 11 is controlled so that it starts to rotate when the temperature of the cooling water rises to a specified temperature, and stops to rotate when it falls to the specified temperature.

[0028] When using the freezer according to the present invention, Stirling refrigerator 7 and brine circulation pump 10 are started and an appropriate temperature is set, and then an appropriate amount of vacuum-packed fish, meat or other foodstuffs to be frozen are placed in water tank 4 through opening of airtight lid 12 and allowed to stand for a prescribed period of time. In one example, cooling head 8 of Stirling refrigerator 7 becomes approximately -95°C, and a brine solution of approximately -32°C is sent to and stored in water tank 4. When the foodstuffs to be frozen are placed in, the temperature of the brine solution rises to approximately -5°C as the foodstuffs are cooled all at once, but the temperature gradually drops as the brine solution circulates, and then stabilizes at approximately -30°C, completing the freezing process in approximately 30 minutes.

[0029] Stirling refrigerators currently available on the market have the advantage of being small, relatively inexpensive, and consuming little power. In the present invention, a Stirling refrigerator 7 having these characteristics is placed under the machine casing 1, and the brine solution cooled by its cooling head 8 is circulated in the water tank 4 placed above the machine casing 1 to perform quick freezing. Also, Stirling refrigerator 7 is cooled by an attached radiator 11 during operation, so that a compact, simple, and easy-to-handle configuration can be achieved, and since it does not take up much space, it can be easily installed in production areas, supermarkets, etc., and can be used for quick freezing on the spot. [Industrial Applicability]

[0030] INDUSTRIAL APPLICABILITY The refrigeration machine according to the present invention is as described above, has a compact and simple configuration, does not take up much space when installed, and is effective in performing refrigeration work with little power consumption, and has great industrial applicability. [Explanation of symbols]

[0031] 1 machine slot 2 Aquarium frame 3. Insulation 4. Aquarium 5 Machine room frame 7. Stirling Refrigerator 8 Cooling Head 9. Inner Cylinder 10 Brine Circulation Pump 11 Radiator 12 Sealing lid 15 Outer cylinder 16 Discharge piping 16a Discharge piping 17 Suction pipe 18 Injection nozzle

Claims

1. A water tank for freezing products is installed in a water tank frame in the upper stage of the machine frame, and a refrigeration device for circulating and supplying a brine solution to the water tank is installed in a machine room frame in the lower stage of the machine frame, The refrigeration equipment includes a Stirling refrigerator, a brine circulating pump that causes a brine solution to flow in and out of an inner cylinder surrounding a cooling head of the Stirling refrigerator and also causes the brine solution to flow in and out of the water tank, and a radiator that cools the Stirling refrigerator.

2. 2. The liquid refrigerator according to claim 1, wherein the cooling water of the radiator flows through a water jacket formed in the Stirling refrigerator to cool the Stirling refrigerator.

3. 3. The liquid refrigerator according to claim 2, wherein the cooling fan of the radiator is controlled to start rotating when the temperature of the cooling water rises to a predetermined temperature and to stop rotating when the temperature of the cooling water falls to the predetermined temperature.

4. 2. The liquid freezer according to claim 1, wherein the water tank is provided with a sealing lid that is opened and closed when inserting or removing a product.

5. 2. The liquid refrigerator according to claim 1, wherein an inner cylinder of the Stirling refrigerator is surrounded by an outer cylinder which is a vacuum insulation chamber.

6. 2. The liquid refrigerator according to claim 1, wherein a jet nozzle is attached to a discharge port of a discharge pipe connected to the water tank.

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