JPS61105071A - Method of operating open showcase - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method of operating a forced circulation type open showcase equipped with a blower that can rotate forward and backward and a defrosting means.

(b) Conventional technology Utility Model Publication No. 43-23802 (70818).

The low-temperature showcase disclosed in Japanese Unexamined Patent Publication No. 47-4''4346 (70B42) is equipped with a cooler and a blower in one passage, and during cooling operation, the cold air that has been heat exchanged with the cooler is blown out by the blower and sucked in by the blower. A cold air curtain is formed at the opening by forced circulation with the low cold air passage to cool the storage room, and during defrosting operation in which the supply of refrigerant to the cooler is stopped, electricity is supplied to the defrosting heater of the cooler. Outside air is introduced into the passage through the outlet, passes through the cooler, and then is blown out diagonally upward from the inlet to prevent the thermal energy of the defrosting heater from affecting the storage chamber.

(c) Problems to be solved by the invention In the above-mentioned conventional technology, when switching from cooling operation to defrosting operation, the air flow is reversed, and the air heated by the heat generated by the defrosting heater is outside the refrigerator. The air is blown upward, and no air curtain is formed at the opening during defrosting operation. As a result, the temperature of the storage room rises quickly due to the intrusion of outside air through the opening, resulting in the problem (b) of deterioration of the quality of stored products, especially in the summer when the outside air temperature is high.

B) Means for Solving the Problems In order to solve the above-mentioned problems, the present invention stores and arranges a cooler and a blower capable of forward and reverse rotation in the passage.

A defrosting means is provided for heating the cooler during defrosting operation.

During the cooling operation, the blower is rotated in the normal direction to form a cold air curtain at the opening, and during the defrosting operation, the blower is rotated in the reverse direction to introduce outside air into the passage.

In an open showcase in which this air is blown out of the refrigerator, the blower is rotated in reverse for a predetermined period of time at the beginning of defrosting operation, and then the blower is rotated in the normal direction to form an air curtain at the opening. How to drive.

(e) Operation During defrosting operation of the cooler, at the beginning of the defrosting operation, the blower is rotated in reverse for a predetermined period of time to discharge residual cold air in the passage, and then the blower is rotated in the normal direction.

(F) Embodiment One embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 4. Components with the same reference numerals in FIGS. 1 to 4 are the same.

As shown in Fig. 2, (1) is a vertically shaped open showcase with an opening (for one person) on one side and an insulating box (2) as its main body. ) allows passage (
5) and a storage chamber (6). Said passage (5
) houses a plate fin type cooler (7) and an axial flow blower (8) that can be rotated in forward and reverse directions, and has an air outlet (9) that opens downward at one end during cooling operation; At the other end, a suction port for cooling operation is formed, opening upward. Further, aB is a defrosting means consisting of a defrosting heater such as an electric heater of about 200 W installed near the surface of the cooler (7) which becomes the air inlet surface during cooling operation. Further, the storage room (6) is provided with a plurality of shelves α2 for displaying stored products and a plurality of fluorescent lamps Q3) for lighting the products.

Figure 1 shows the operation control circuit of the open showcase (1), in which the timer motor <x6M>b of the defrosting timer tte is connected between the first and second power lines (14) and (15). There is. Also, (1681), (168,), (
16S3) is a defrosting timer (switching contact piece of 1119,
These are cooling contacts and defrosting contacts.

Here, the cooling contact (16Sz) is connected to the wc2 power line α9 through a series circuit of a thermostat (17) for controlling the temperature inside the refrigerator and a relay coil for the compressor (hereinafter referred to as the first coil) Q8). There is. Also, the defrost contact (163
) are the overheating preventer (19) and the relay coil of the defrosting means U (
(hereinafter referred to as the second coil) (hereinafter referred to as the second coil) (binary value) is connected to the second power supply line (15).Furthermore, (21S) is a timer switch for the blower operation control timer Cυ (hereinafter referred to as the blower timer switch). @ is the relay coil for blower operation (hereinafter referred to as the third coil).

(21M) is a timer motor for the blower. In addition, the compressor (c) is connected to the power supply line (241) via the compressor relay switch (188), and is connected to the defrosting means I beam race innote (208), and furthermore, the blower (8) is connected to the operating capacitor ( A first relay switch (marked Q) for normally open blower operation and a second relay switch for normally closed blower operation are connected to the power source (24).

The operation of the operation control circuit will be explained below.

The switching contact piece (163,) for the defrosting timer tilt is connected to the cooling contact (1
When the compressor relay coil αυ is closed, the energization of the compressor relay coil αυ is controlled by the on/off of the thermostat (1η), and the third coil (the second relay coil is not energized and the second relay coil for blower operation is on). However, the blower (8) operates in normal rotation, and the cold air that has undergone heat exchange with the cooler (force) is circulated as shown by the arrow in FIG.

A cold near-curtain is formed at the opening (IA).

When the cooling operation continues for a predetermined time and the timer motor (16M) counts up, the switching contact (168,) switches to the defrosting contact (1683), and the first coil goes into amorphous sleep for a second. The compressor relay switch (188') is turned off and the operation of the compressor (c) is stopped. With this stop, the second coil (2) is energized and the relay switch (208') is turned off.
) is turned on, the defrosting means (11) starts generating heat by being energized, and furthermore, the blower timer motor (21M) is energized and starts counting, and the blower timer switch (
The third coil (218) is energized, the second relay switch (support) for blower operation is turned off, and the first relay switch CI!e for blower operation is turned on.

The blower (8) performs reverse operation, and as shown by the arrow in Fig. 3, outside air is sucked from the outlet (9) into the passage (5), passes through the cooler (forced), and enters the air intake. ■It is blown out of the refrigerator.

When a preset predetermined time (for example, 40 seconds) elapses after the defrosting operation starts and the cold air in the passage (5) is blown out, the timer motor (21M) for the blower starts counting up. Then, the blower timer switch (21S) is turned off, the third coil (22 is de-energized, and the blower operation control timer I21) is reset.

Incidentally, the predetermined time is set so that the temperature inside the passage (5) becomes 0° C. or higher when the timer Cυ performs count amplification. Also, the first relay switch Ce for blower operation is turned off, the second relay switch for blower operation is turned on, and the blower (8) starts normal rotation and moves toward the passage as shown by the arrow in FIG. The air inside (5) circulates in the same way as during the cooling operation, and an air curtain is formed at the opening (IA) of the oven showcase (1).

This circulating air is heated by the defrosting means αD, and then passes through the cooler (7), where it exchanges heat with the ice and frost, and its temperature is lowered.

When the blower (8) is operating in normal rotation, the cooler (
7) When the defrosting operation progresses and the ice/frost melts, a defrosting end detection device (not shown) such as a defrosting return thermostat detects a rise in the temperature of the cooler (power).

The defrosting timer motor (16M) is reset and starts counting again, and the switching contact (163,') switches to the cooling operation contact (1682), and cooling operation resumes based on the on/off of the thermostat α. be done.

Therefore, since the blower (8) is operated in reverse for a predetermined period of time at the beginning of the defrosting operation, unexpected air sucked from the air outlet (9) is sent to the passage (5) while the blower (8) is operated in reverse for a predetermined period of time. The residual cold air in this passage is discharged to the outside of the refrigerator, and the outer wall of the partition plate (4), which has been cooled by the cold air and whose temperature has decreased,
The inner wall of the insulation box (2) is heated.

That is, during the cooling operation, the temperature of the cooler (7) is 1, for example, -10°C.
The temperature of the wall surface of the passageway (5), which has been cooled to a certain temperature, rises.

Further, the residual cold air is blown out from the suction port αB. After the air inside the passage (5) reaches 0°C or higher due to the intake of outside air, the blower (8) starts normal operation, and the air warmed by the heat generated by the defrosting means aD is transferred to the cooler ( 7), the temperature is lowered to lower than that of the outside air by melting the ice and frost, and this heating and cooling process is repeated during circulation. As a result, the cooler (
It is possible to quickly melt ice and frost by force b"--and to shorten the defrosting time--Furthermore, during defrosting operation, after the blower (8) continues to operate in reverse for a predetermined period of time, it starts operating in forward rotation. is performed, and an air curtain with a temperature lower than the outside air is formed at the opening (IA) of the oven showcase (1), so that the outside air is stored in the storage room (6).
) can be almost eliminated, and as a result, it is possible to suppress the rise in the internal temperature of dust in the storage room (6) during defrosting operation, and it is also possible to maintain the quality of stored products.

In addition, in the above embodiment, the blower (8
), the defrosting means (11) is energized during the reverse operation, but even if the defrosting means (11) is not energized during the reverse operation, the same effects as in the above embodiment can be obtained. .

(G) Effects of the Invention Since the present invention is a method of operating an open showcase as described above, at the beginning of defrosting operation, the blower is reversed and the cold air formed during cooling operation is discharged from the passage to the outside of the refrigerator. 1
After the temperature in the passage increases, the blower is rotated in the normal direction, and when the air blower is reversed, the air outside the refrigerator that is sucked into the passage is warmed by the defrosting means and sent to the cooler. It is not necessary to use the heat generated by the means to heat the passage wall surface and the residual cold air, and as a result, the defrosting operation time can be shortened, and the blower can be used after the reverse operation is completed.

Normal rotation is performed, and an air curtain with a temperature lower than the temperature of the outside air is formed at the opening of the open showcase, so it is possible to almost eliminate the intrusion of outside air into the inside of the refrigerator. In addition to shortening the defrosting time, the rise in internal temperature during defrosting operation can be suppressed to a small level, and the quality of stored products can be maintained.

[Brief explanation of the drawing]

1 to 4 show one embodiment of the present invention. Figure 1 is a schematic operation control circuit diagram of the open showcase.
FIGS. 2 to 4 are schematic vertical cross-sectional views of the open showcase showing air flows during cooling operation and defrosting operation, respectively. (1)...Open showcase, (5)...Aisle, (7)...Cooler, (8)...Blower, (i
ll...Defrosting means. Applicant Sanyo Electric Co., Ltd. and one other representative Patent attorney Shizuo Sano Figure 2 Figure 3

Claims (1)

[Claims] 1. A cooler and a blower capable of forward and reverse rotation are housed in the passage, and a defrosting means is provided for heating the cooler during defrosting operation;
During cooling operation, the blower is rotated forward to form a cold air curtain at the opening, and during defrosting operation, the blower is reversed to introduce outside air into the passage, and this air is blown out to the outside of the refrigerator. A method of operating an open showcase in the showcase, comprising rotating the blower in reverse for a predetermined period of time at the beginning of defrosting operation, and then rotating the blower in the normal direction.