JPH0522147B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a multi-tiered open low-temperature case in which stored products are displayed in a refrigerated state by closing the opening of the case body with an air curtain of cold air. In particular, it relates to heat exchange with the circulating cold air of the main evaporator.

(b) Conventional technology A multi-tiered open low-temperature case for displaying stored products in a refrigerated state by closing the opening of the case body with a cold air curtain was developed in Japanese Patent Laid-Open No. 58
-There was something shown in Publication No. 178176.

(c) Problems to be solved by the invention What is disclosed in JP-A-58-178176 is that
The main evaporator was disposed in contact with the inner wall of the cold air circuit. Therefore, when frost adheres to the vicinity of the air inlet of the main evaporator, there is a problem in that less cold air can pass through the main evaporator, making it impossible to obtain sufficient cooling power inside the refrigerator.

(d) Means for solving the problems and their effects This invention has been made in view of the above circumstances, and provides a method for connecting the main evaporator and a large amount of circulating cold air by supporting the main evaporator with a specific holder. This enables heat exchange with

The detailed structure consists of a multi-stage open case body and a refrigerant circuit that constitutes a refrigeration cycle, and the open case body sends air for the room curtain from the upper edge of the opening of the body to the lower edge. , an air circulation means for closing the opening with an air curtain, and an air circulation means for supplying cold air from the upper edge of the opening to the lower edge of the opening substantially parallel to the air curtain and inside the open case body from the air curtain through an evaporator of a refrigerant circuit. A multi-stage open low-temperature case equipped with cold air circulation supply means for refrigerating products that are sent and stored and displayed inside the open case body,
The refrigerant circuit is in heat exchange contact with an auxiliary evaporator disposed in the cold air circulation path via a compressor and a condenser, and is provided with a first expansion valve and a defrost heater to operate the auxiliary evaporator in the cold air circulation path. A main circuit leading to the main evaporator and the compressor arranged on the lower edge side is branched from between the contact portion of the compressor and the auxiliary evaporator, and is connected to a second expansion valve, the auxiliary evaporator, the compressor, and the main evaporator. It consists of a branch circuit that is replaced from the main circuit when defrosting the
Furthermore, a holder for lifting and holding the main evaporator from the road surface of the cold air circulation path is disposed, and the holder is provided with a plurality of ventilation holes for supplying circulating cold air to the road surface side of the main evaporator. The type is an open low temperature case.

(E) Embodiments This invention will be described in detail based on embodiments shown in FIGS. 1 to 5. However, the invention is not limited thereby.

As shown in FIG. 1, the multi-stage open low-temperature case R includes a case body 2 with an opening for taking products in and out, and a shelf 3 for displaying products. The multistage open low-temperature case R is equipped with an air circulation means for closing the opening 1 of the case body 2 with an air curtain and a cold air circulation supply means 4. The air circulation means includes a discharge port 5, a suction port 6, a fan motor (not shown), and an air flow path 7 formed within the case body 2. Circulating air circulates in the direction of arrow A.

The cold air circulation supply means 4 enters the suction port 9 from the circulating cold air discharge port 8, continues to the cold air circulation path 10, passes near the fan motor 11, defrost heater 12, main evaporator 13, and auxiliary evaporator 14, and then returns to the discharge port 8. more circulated. The circulating cold air of the cold air circulation supply means 4 is as shown in the direction of arrow B.

As shown in FIG. 2, the main evaporator 13 is mounted and held on a holding member 16 having a plurality of ventilation holes 15 through which circulating cool air can pass. Therefore, the held portion 17 of the main evaporator 13 comes into contact with the circulating cold air and can exchange heat.

FIG. 3 shows the refrigerant circulation system of the cold air circulation supply means 4. During normal operation, the solenoid valve 18 is energized and opened, and the refrigerant is transferred to the compressor 20,
It circulates through the condenser 21, solenoid valve 18, expansion valve 22, main evaporator 13, and compressor 20.
Here, the main evaporator 13 generates cold heat and provides the cold heat to the air within the cold air circulation path 10. During this heat exchange of cold heat supply, the main evaporator 13
Each part is in contact with a large amount of circulating cold air, and heat exchange is performed evenly in each part. Therefore, frost does not adhere to specific parts of the main evaporator 13 early and block the cold air circulation path, and furthermore, the frost prevents heat exchange between the main evaporator 13 and the circulating cold air at an early stage. Not often. Further, even if frost adheres to the main evaporator 13, there is no large difference in the frost depending on the main evaporator 13, so defrosting can be easily performed. Furthermore, since frost is less likely to adhere to the main evaporator 13, the main evaporator 13 can provide cooling heat to the circulating cold air as specified, and the circulating cold air provides the desired cooling heat to the stored and displayed products to maintain the refrigerated state. be able to.

When defrosting the main evaporator 13, the solenoid valve 19 is energized by the action of the switching means 24 and becomes open. The cold air circulation supply means 4 includes a compressor 20, a condenser 21, a solenoid valve 19, an expansion valve 2, and a refrigerant.
3, circulates to the auxiliary evaporator 14 and compressor 20. At this time, the defrost heater 1 is activated by the operation of the defrost timer 24 that constitutes the switching means.
2 is energized and generates heat to melt the frost attached to the main evaporator 13. The defrost heater 12 is located upstream of the cold air circulation of the main evaporator 13, so it can easily supply heat to the main evaporator 13, and it is located symmetrically with the auxiliary evaporator 14 with the main evaporator 13 in between. The effect on the cooling and heat supply of the air conditioner is minimal. FIG. 4 shows a sequence circuit diagram showing the operating state of the cold air circulation supply means 4.

FIG. 5 shows an electric circuit diagram related to the cold air circulation supply means 4. In addition, 25 is a fan motor of the air circulation means, 26 is a start switch, 27, 2
8 is an auxiliary relay, 29 is a compressor magnet switch, 30 is an overload relay, 3
1 is a heating preventer, and 32 is a thermostat.

(F) Effects of the Invention According to the present invention, by having the configuration in which the evaporator is lifted and held by a holding member through which circulating cold air can pass, heat exchange between the main evaporator and a large amount of circulating cold air becomes possible. Since frost does not form locally, defrosting can be performed easily, and the specified amount of cold and heat can be supplied to the circulating cold air, the products stored and displayed inside the case body can be refrigerated and stored as specified. The effect is that it can be done.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of one embodiment of the present invention;
The figure is a perspective view of the main part showing the holding state of the main evaporator of this embodiment, FIG. 3 is a configuration explanatory diagram showing the refrigerant circulation system of the cold air circulation supply means of this embodiment, and FIG. 4 is the cold air circulation of this embodiment. FIG. 5 is a sequence circuit diagram showing the operating state of the supply means. FIG. 5 is an electric circuit diagram relating to the cold air circulation supply means of this embodiment. R...Multi-stage open low temperature case, 1...Opening, 2...Case body, 4...Cold air circulation supply means, 5, 8...Discharge port, 6, 9...Suction port, 10
...Cold air circulation path, 12...Defrost heater, 1
3...Main evaporator, 14...Auxiliary evaporator, 15...Vent hole, 16...Holding member, 17...
...Holded part, 18, 19... Solenoid valve, 24...
switching means.

Claims (1)

[Claims] 1. Consisting of a multi-stage open case body and a refrigerant circuit constituting a refrigeration cycle, the open case body supplies air for room curtains from the upper edge to the lower edge of the opening of the body. an air circulation means for feeding and closing the opening with an air curtain; and cooling air is sent from the upper edge of the opening to the lower edge of the opening almost parallel to the air curtain and inside the open case body from the air curtain via an evaporator of the refrigerant circuit. In a multi-stage open low temperature case, the refrigerant circuit is arranged in the cold air circulation path via a compressor and a condenser. a main evaporator connected to the auxiliary evaporator in a heat exchange manner and provided with a first expansion valve and a defrost heater, the main circuit leading to the compressor and the main evaporator disposed on the lower edge side of the auxiliary evaporator in the cold air circulation path; It branches from between the contact portion of the compressor and the auxiliary evaporator, and includes a second expansion valve, a branch circuit that runs from the auxiliary evaporator to the compressor and is replaced from the main circuit when the main evaporator is defrosted; A multi-stage open door comprising a holder for lifting and holding the main evaporator from the road surface of the cold air circulation path, and a plurality of ventilation holes formed in the holder to send circulating cold air to the road surface side of the main evaporator. Low temperature case.