JPH09269179A - Defroster for refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the frost left on coolant piping on the coolant inlet side of an evaporator with a simple structure by arranging heat transferring members that are attached heat conductively to both the coolant piping on the coolant inlet side of the evaporator and a defrosting heater. SOLUTION: In a chilled showcase 1, a storing compartment 9 is arranged inside an inner layer partition 6, a fan case 14 is arranged inside a bottom part duct 13 and an evaporator 16 is vertically arranged inside an inner layer duct 8. A defrosting heater 34 is arranged under the evaporator 16 and rising parts 34A are formed by bending at both side parts of it. Heat conductive members 36 that comprise curved parts 36A and 36B are provided, one of the curved parts 36A is fit to the coolant inlet piping 32A of the evaporator 16, the other curved part 36B is fit to the rising part 34A of the defrosting heater 34, and between 36A and 32A and between 36B and 34A are connected heat conductively. Therefore, the heat from the defrosting heater 34 can be transferred to the coolant piping 32 on the coolant inlet side through the heat conductive member 36 in the defrosting of the evaporator 16 and the generation of remaining frost is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defrosting device for defrosting a cooler provided in a cooling device such as a low temperature showcase or a refrigerator.

[0002]

2. Description of the Related Art Conventionally, in a low-temperature showcase installed in a supermarket, for example, as shown in Japanese Patent Publication No. 6-55050 (F25D17 / 08), a storage room for displaying products in a heat insulating wall and an outside thereof are provided. A duct as a cold air passage is formed, a cooler and a blower (a blower fan) are installed in the duct, and cool air that has exchanged heat with the cooler is circulated in the storage chamber by the blower.

Further, since frost is formed on the cooler by such a cooling operation, a defrost heater consisting of an electric heater is installed on the windward side of the cooler, and the heat generated by the defrost heater causes the cooler to frost. It is designed to melt and remove frost.

FIG. 4 is an enlarged view of the refrigerant inlet / outlet portion of the conventional cooler 101 according to FIG. The cooler 101 is a so-called plate fin type evaporator, and is configured by attaching a plurality of fins (not shown) to the refrigerant pipe 102 bent in a meandering shape. Reference numeral 103 is a tube plate that holds the refrigerant pipe 102 on both sides of these fins.
Is bent in a U-shape outside the tube sheet 103.

Reference numeral 102A is a refrigerant inlet pipe, which rises outside the tube plate 103 and is drawn into the upper part of the cooler 101. Further, 102B is a refrigerant outlet pipe, which is drawn out from the lower portion of the cooler 101 to the outside of the tube plate 103.

Reference numeral 104 denotes the above-mentioned defrosting heater, which is composed of a sheathed heater in which a heating wire is housed in a metal pipe, and is arranged on the lower side (windward side) of the cooler 101, and both side portions thereof are the tube sheet 103. Is bent up to the outside of. When defrosting the cooler 101, the defrost heater 104 is energized to generate heat and the upper cooler 101 is heated to melt and remove frost.

[0007]

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention
The temperature rise of the refrigerant inlet pipe 102A rising outside 03 is delayed later than other parts, and there is a risk of residual frost. In particular, in this type of low temperature showcase, usually, a plurality of showcase coolers 101 are provided with liquid solenoid valves (refrigerant inlet pipe 102) for one condensing unit.
It is connected to the piping via the (A side), and when defrosting the cooler 101, the liquid solenoid valve on the inlet side is closed to collect the refrigerant in the cooler 101 in the compressor of the condensing unit. After that, the defrost heater 104 is energized.

Therefore, heat conduction due to the refrigerant inside the cooler 101 cannot be expected, so that the refrigerant inlet pipe 102A.
The temperature rise is only due to heat conduction by air, which has a low heat conductivity, and the risk of residual frost becomes even greater.

Therefore, conventionally, as shown in FIG. 4, the heat insulating material 1 is used.
Although the method of winding 06 around the refrigerant inlet pipe 102A to prevent frost formation has been adopted, it is extremely difficult to perform heat insulation without a gap, and even if a little water enters, frost residue is generated and removed. There was a problem of falling into bad frost.

Further, a method of additionally installing a heater in the refrigerant inlet pipe 102A instead of the heat insulating material 106 to melt the frost is conceivable, but this time, the power consumption increases and the component cost significantly increases. Problems such as occur.

Further, particularly in the case of the method of defrosting after the pump down, a solenoid valve is attached to the suction side (refrigerant outlet pipe 102B side) of the condensing unit, and the solenoid valve is closed during defrosting to cool the cooler. Although there is also a method of expecting heat conduction from the refrigerant by allowing the refrigerant to remain in 101, it causes a significant cost increase as in the case of the heater.

The present invention has been made to solve the above-mentioned conventional technical problems, and a cooling device capable of preventing frost residue on the refrigerant pipe on the refrigerant inlet side of the cooler with a simple structure. The present invention provides a defrosting device.

[0013]

That is, the defrosting apparatus of the present invention circulates cool air, which has exchanged heat with a cooler equipped with a refrigerant pipe, in a space to be cooled and cools it by heat generation of a defrosting heater. The present invention is applied to a cooling device formed by removing frost from a cooler, and is provided with a heat transfer member thermally conductively attached to both the refrigerant pipe on the refrigerant inlet side of the cooler and the defrost heater.

According to the present invention, since the heat transfer member is attached to both the refrigerant pipe on the refrigerant inlet side of the cooler and the defrost heater in a heat conductive manner, the defrost heater is used when the cooler is defrosted. The heat from the heat transfer member can be directly transferred to the refrigerant pipe on the refrigerant inlet side. As a result, it becomes possible to smoothly and effectively heat the refrigerant inlet side refrigerant pipe of the cooler, which eliminates the occurrence of frost residue in the cooler in the relevant portion and reduces the cooling capacity. You will be able to avoid.

In particular, since the heat transfer member is simply attached to the refrigerant pipe on the refrigerant inlet side and the defrost heater, there is almost no problem in terms of cost.

The defrosting device of the cooling device according to the second aspect of the invention is
In the above, the heat transfer member includes a plurality of curved portions, and the curved portions are fitted into the refrigerant pipe and the defrost heater, respectively.

According to the second aspect of the present invention, in addition to the above, the heat transfer member is provided with a plurality of curved portions, and the curved portions are respectively fitted to the refrigerant pipe and the defrost heater. While it has a simple shape, it is possible to attach it to the refrigerant pipe and the defrost heater by an extremely simple work such as fitting, so that the cost of parts can be further reduced and the assembling workability can be improved. It will be.

[0018]

Next, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a vertical sectional side view of a low temperature showcase 1 as an embodiment of a cooling device to which the present invention is applied, and FIG. 2 is an enlarged view of a refrigerant inlet / outlet portion of a cooler 16 of the low temperature showcase 1.

The low temperature showcase 1 of the embodiment is a vertical freezing / refrigerating type open showcase installed in a store such as a supermarket, and has a heat insulating wall 2 having a substantially U-shaped cross section and an installation site. It is composed of side plates (not shown) attached to both sides of the heat insulating wall 2. An outer layer partition plate 4 and an inner layer partition plate 6 are attached to the inside of the heat insulating wall 2 with a space therebetween, and an outer layer duct 7, inner and outer layer partition plates 6, 4 are provided between the heat insulating wall 2 and the outer layer partition plate 4. The space between them is an inner layer duct 8 and the inside of the inner layer partition plate 6 is a storage chamber 9 as a space to be cooled.

A plurality of shelves 11 ... Are erected in the storage chamber 9 with a low inclination to the front side, and a deck pan 12 is attached to the bottom of the storage chamber 9.
Below 2 is a bottom duct 1 communicating with both ducts 7 and 8.
It is set to 3. A fan case 14 having a blower (not shown) is installed in the bottom duct 13, and a cooler 16 is vertically installed in the inner layer duct 8.

An outer layer discharge port 22 and an inner layer discharge port 23 are arranged side by side at the upper edge of the front opening 21 of the storage chamber 9. The outer layer discharge port 22 is located in the outer layer duct 7 and the inner layer discharge port. 23 communicate with the inner layer ducts 8, respectively. A suction port 24 is formed at the lower edge of the opening 21 and communicates with the bottom duct 13.

When the blower in the fan case 14 is operated, the air in the bottom duct 13 is blown toward the rear inner and outer layer ducts 7 and 8, and is blown up as it is in the outer layer duct 7, and at the same time, the inner layer is blown up. In the duct 8, it is blown up after exchanging heat with the cooler 16, and is blown out from the inner and outer layer discharge ports 22 and 23 at the upper edge of the opening 21 toward the suction port 24 at the lower edge.

As a result, an inner cool air curtain and an outer air curtain that protects the inner cool air curtain are formed in the opening 21 of the storage chamber 9 to prevent or suppress the invasion of outside air from the opening 21, and A part of the cool air curtain on the inner side circulates in the storage chamber 9 to cool the storage chamber 9. Then, the cool air or the like returns from the suction port 24 to the bottom duct 13 and is sucked into the blower again.

On the other hand, an exterior panel 20 projecting forward in the longitudinal direction is attached to the front end of the top wall of the heat insulating wall 2. The inside of the exterior panel 20 and the inner layer discharge port 2 are attached.
Fluorescent lamps 26 for illuminating the vicinity of the opening 21 and the inside of the storage chamber 9 are attached to the lower side of the inner partitioning plate 6 inside 3 and the lower surface of the tip of each shelf 11.

Here, the cooler 16 is a so-called plate fin type evaporator, and is constituted by attaching a plurality of fins (not shown) to the refrigerant pipe 32 bent in a meandering shape. Reference numeral 33 is a tube plate that holds the refrigerant pipe 32 on both sides of these fins, and the refrigerant pipe 32 is bent in a U shape outside the tube plate 33.

32A is a refrigerant inlet pipe, which rises outside the tube plate 33 and is drawn into the upper part of the cooler 16. Further, 32B is a refrigerant outlet pipe,
It is pulled out from the lower portion of the cooler 16 to the outside of the tube sheet 33.

The refrigerant inlet pipe 32A is installed via a liquid solenoid valve and an expansion valve (not shown) in a condensing unit (not shown) such as a machine room of a store. The refrigerant outlet pipe 32.
B is connected to the low pressure pipe of the condensing unit.

Reference numeral 34 is a defrosting heater, which is composed of a sheathed heater containing a heating wire in a metal pipe,
An upright portion 34 </ b> A, which is arranged on the lower side (windward side) of the cooler 16 and which rises to the outside of the tube sheet 33, is formed on both sides of the cooler 16.

Further, reference numeral 36 denotes a heat transfer member according to the present invention, which is a heat conductive metal plate such as aluminum.
As shown in FIG. 3, the two curved portions 36A and 36B are bent adjacent to each other and are open on opposite sides. The curvature of the curved portion 36A is slightly smaller than the outer peripheral surface (for example, diameter 12.2 mm) of the refrigerant inlet pipe 32A of the cooler 16, and the curvature of the curved portion 36B is the outer peripheral surface of the defrost heater 34. (For example, diameter 10mm)
It is considered to be a small value.

Then, as shown in FIG. 2, the curved portion 36A is formed.
Is fitted to the outer surface of the refrigerant inlet pipe 32A, and the curved portion 36B on the opposite side is fitted to the outer surface of the standing portion 34A of the defrosting heater 34, so as to be mounted in a heat conductive manner between them.

Next, at the time of defrosting the cooler 16, first, the liquid electromagnetic plate is closed, and a so-called pump down operation for collecting the refrigerant in the cooler 16 is performed by the compressor of the condensing unit. When the refrigerant recovery of all the low temperature showcases 1 ... Connected to the condensing unit as described above is completed, a low pressure switch (not shown) is activated to stop the compressor.

After completion of the pump down, the defrost heater 34 is energized to generate heat and heat the upper cooler 16,
Melt and remove frost. Further, the heat generated by the defrosting heater 34 is transmitted from the standing portion 34A to the heat transfer member 36, and is transmitted to the refrigerant inlet pipe 32A through the heat transfer member 36 to heat it.

As described above, in the present invention, the heat transfer member 3 is connected to both the refrigerant inlet pipe 32A of the cooler 16 and the defrost heater 34.
Since 6 is attached in a heat conductive manner, the heat from the defrost heater 34 can be directly transferred from the heat transfer member 36 to the refrigerant inlet pipe 32A when the cooler 16 is defrosted. As a result, the refrigerant inlet pipe 3 in which frost residue of the cooler 16 is likely to occur
2A can be heated smoothly and effectively, the generation of residual frost in the cooler 16 in the relevant portion can be eliminated, and a decrease in cooling capacity can be avoided in advance.

Further, since the heat transfer member 36 is simply attached to the refrigerant inlet pipe 32A and the defrost heater 34, there is almost no problem in terms of cost. In particular, the heat transfer member 36 is provided with a plurality of curved portions 36A and 36B, and the curved portions 36A and 36B are fitted into the refrigerant inlet pipe 32A and the defrost heater 34, respectively.
While having a simple shape, it is possible to attach the refrigerant inlet pipe 32A and the defrosting heater 34 by an extremely simple work such as fitting, and it is possible to further reduce the component cost and improve the assembly workability. become able to.

In the embodiment, the present invention is applied to the open showcase in which the cooler is defrosted after the pump is down. However, the present invention is not limited to this, and a low-temperature showcase with a door, a commercial / household refrigerator, and a prefabricated house A refrigerator or the like may be used, and the present invention is also effective for a normal defrosting method in which a single cooler is connected to one compressor and the compressor is stopped during defrosting to heat the defrosting heater. .

[0036]

As described above in detail, according to the present invention, the heat transfer members attached to the defrosting heater and the refrigerant pipe on the refrigerant inlet side of the cooler are provided in a heat conductive manner. During defrosting, heat from the defrosting heater can be directly transferred from the heat transfer member to the refrigerant pipe on the refrigerant inlet side. This makes it possible to smoothly and effectively heat the refrigerant pipe on the refrigerant inlet side of the cooler where frost residue is likely to occur, eliminating the occurrence of frost residue in the cooler in the part,
It becomes possible to avoid deterioration of the cooling capacity.

In particular, since the heat transfer member is simply attached to the refrigerant pipe on the refrigerant inlet side and the defrost heater, there is almost no problem in terms of cost.

According to the second aspect of the present invention, in addition to the above, the heat transfer member is provided with a plurality of curved portions, and the curved portions are respectively fitted to the refrigerant pipe and the defrost heater. While it has a simple shape, it is possible to attach it to the refrigerant pipe and the defrost heater by an extremely simple work such as fitting, so that the cost of parts can be further reduced and the assembling workability can be improved. It will be.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a low temperature showcase to which the present invention is applied.

2 is a perspective view of a refrigerant inlet / outlet portion of the cooler of FIG. 1. FIG.

FIG. 3 is a perspective view of a heat transfer member of the present invention.

FIG. 4 is a perspective view of a refrigerant inlet / outlet portion of a conventional cooler.

[Explanation of symbols]

 1 Low Temperature Showcase 9 Storage Room 16 Cooler 32 Refrigerant Pipe 32A Refrigerant Inlet Pipe 32B Refrigerant Outlet Pipe 34 Defrost Heater 34A Standing Part 36 Heat Transfer Member 36A, 36B Curved Part

Claims (2)

[Claims] 1. A cooling device comprising a cooler having heat exchanged with a cooler equipped with a refrigerant pipe, which is circulated in a space to be cooled for cooling, and frost formed on the cooler is removed by heat generated by a defrost heater. A defroster for a cooling device, wherein a heat transfer member that is mounted in a heat conductive manner is provided on both the refrigerant pipe on the refrigerant inlet side of the cooler and the defrost heater. 2. The defroster for a cooling device according to claim 1, wherein the heat transfer member includes a plurality of curved portions, and each curved portion is fitted into the refrigerant pipe and the defrost heater, respectively.