JP3213147B2 - Refrigerant circulation circuit for ice machines, etc. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a high pressure compressor from a compressor.
When the high-temperature vaporized refrigerant flows into the evaporator to remove the ice that has grown on the ice making plate or the like, the pressure at the refrigerant outlet side of the compressor is reduced as necessary, thereby reducing the performance of the compressor and causing failure. The present invention relates to a refrigerant circuit of an ice maker or the like configured to prevent the occurrence thereof beforehand.

[0002]

2. Description of the Related Art An ice making machine for automatically producing a large number of ice blocks is provided with a refrigeration circuit for circulating a refrigerant. By supplying the "hot gas" to the evaporator attached to the ice making plate, the ice making plate is heated to accelerate the detachment of the ice. For example, FIG.
Is a falling ice machine for continuously producing ice blocks by spraying and supplying ice making water to a vertically standing ice making plate,
An evaporator 14, which is drawn out of the refrigeration circuit 12 shown in FIG. 4 and meanders in the horizontal direction, is closely fixed between the two vertically arranged ice making plates 10, 10, and circulates a refrigerant during the ice making operation to make the ice making plates. Forcibly cool 10,10. On the ice making surface side of each ice making plate 10, a plurality of ridges 10a are formed in the width direction, and ice blocks 16 are generated at positions corresponding to the evaporator 14 between the adjacent ridges 10a, 10a. I have. Immediately below the ice making plates 10 and 10, a water collecting plate 18 having a plurality of through holes 18a is provided in an inclined manner.
The ice making water that has not been supplied to 0, 10 and has not been frozen is collected and stored in an ice making water tank 20 located below through the through hole 18a. In addition, the water collecting plate 18 holds the ice blocks 16 that have been separated by the deicing operation and fall.
Also serves as a guide to the ice storage 22 arranged diagonally below.

[0003] The circulating pump 24 is
The ice making water supply pipe 26 led out through the ice making plate 1
Ice making water sprayer 28 provided above 0, 10 and on the ice making surface side
Connected to The ice making water sprayer 28 is provided with a large number of water sprinkling holes (not shown), and the ice making water pumped from the tank 20 during the ice making operation is adjusted to the freezing temperature of the ice making plates 10 and 10 from the water sprinkling holes. The ice is sprayed down onto an ice making surface that has been cooled down to form ice blocks 16 of a required shape on the ice making surface.

FIG. 4 shows a schematic configuration of a refrigeration circuit suitably used in the above-described automatic ice maker. The refrigeration circuit 12 includes a compressor 30 for compressing a refrigerant such as Freon and a compressor 30 for compressing the refrigerant. 32, which receives a supply of high-pressure, high-temperature vaporized refrigerant compressed by the compressor 30, an expansion valve 34, to which liquefied refrigerant condensed by the condenser 32 is supplied, and a refrigerant expanded and vaporized through the expansion valve 34 And an evaporator 14 that receives the supply of water. Further, in the evaporator 14, heat is exchanged with the vaporized refrigerant expanded through the expansion valve 34, and the ice making plates 10, 10 attached to the evaporator 14 are cooled to below freezing points, whereby the ice making plates 10, 10 The ice making water flowing down is gradually frozen. Then, the vaporized refrigerant whose temperature has been increased by heat exchange in the evaporator 14 is returned to the compressor 30 to be compressed to a high pressure and a high temperature, and then subjected to recirculation. Reference numeral 36 denotes a detecting means for detecting the refrigerant temperature at the refrigerant outlet side of the evaporator 14, and the detecting means 36 controls the throttle of the expansion valve 34.

A pipe 38 branched from a pipe 37 on the outlet side of the compressor 30 is provided with a hot gas valve 40 such as an electromagnetic valve.
Is connected to the inlet side of the evaporator 14 via a so-called hot gas circuit 42. And hot gas valve 4
Numeral 0 indicates that the refrigerant is closed during the ice making operation to prevent the circulation of the refrigerant in the hot gas circuit 42, and the refrigerant is circulated only in the refrigeration circuit 12. When the ice making operation on the ice making plates 10 and 10 is completed and the operation shifts to a deicing operation for dropping and removing ice, the hot gas valve 40 is opened to circulate a high-temperature refrigerant (hot gas) through the hot gas circuit 42. Thereby, the evaporator 14
The ice making plates 10, 10 accompanying the ice making plates 10 and 10 are heated,
The adhesion of the ice block 16 formed on the base 10 is released, and the ice block 16 is dropped by its own weight.

[0006]

As described above, when the ice making machine shifts to the deicing operation, the hot gas valve 40 is switched from the closed state to the open state, and the refrigerant circulation in the refrigeration circuit 12 is stopped. A high-pressure and high-temperature vaporized refrigerant is supplied to the evaporator 14 from the outlet side of the compressor 30. However, as can be seen from FIG. 4, no closing means such as a valve is interposed on the inlet side of the condenser 32. For this reason, during the deicing operation, the compressor 3
Not all of the hot gas discharged from 0 is supplied to the hot gas circuit 42, and only the hot gas that makes up the majority of the hot gas circulates through the hot gas circuit 42. Then, a small amount, but a part, of the hot gas flows toward the condenser 32, which has good heat radiation, and liquefies here and stagnates (this is referred to as “stagnation”). When a part of the hot gas falls in the refrigeration circuit 12 connected to the condenser 32, the hot gas circuit 4
2, the circulation amount of the hot gas decreases by the stagnation amount over time. Accordingly, the deicing ability of the evaporator 14 gradually decreases, which indicates that a long time is required for the deicing operation. In particular, such drawbacks become noticeable when the ambient temperature is low. In a refrigeration circuit in which a receiver is provided on the outlet side of the condenser 32, the amount of the hot gas stagnation increases, and the deicing ability further decreases.

[0007] In the ice making machine, the ice making plate 1 is operated by deicing operation.
A thermostat (not shown) measures the temperature rise of the ice making plates 10 and 10 caused by the falling of ice blocks 16 from 0 and 10.
To switch the operation from the deicing operation to the ice making operation. Hot gas circuit 4 for the reasons described above
When the circulation amount of hot gas in the ice making plate 2 decreases, the ice making plate 1
The ice blocks 16 formed at 0 and 10 may not fall uniformly, and the ice blocks 16 near the thermostat arrangement position may fall quickly. In this case, although the ice block 16 in other places is not dropped, the operation is switched from the deicing operation to the ice making operation, and there is a problem that double ice making is caused.

As a means for addressing the above-mentioned problem, FIG.
As shown in the figure, the ice making machine performs the de-icing operation on the downstream side (condenser 32 side) in the flow direction of the refrigerant from the connection position of the pipe body 37 in the pipe body 37 connecting the compressor 30 and the condenser 32. It has been proposed to interpose a solenoid valve 44 that closes when the transition occurs. That is, during the ice making operation, the electromagnetic valve 44 is opened to circulate the refrigerant through the refrigeration circuit 12, and the hot gas valve 40 is closed to prevent the refrigerant from circulating in the hot gas circuit 42. When the operation shifts from the ice making operation to the deicing operation, the electromagnetic valve 44 is closed to prevent the circulation of the refrigerant in the refrigeration circuit 12, and the hot gas valve 40 is opened to allow the hot gas circuit 42 Hot gas). As a result, all of the hot gas discharged from the compressor 30 during the deicing operation is supplied to the hot gas circuit 42 to prevent a decrease in the deicing ability, thereby shortening the time required for the deicing operation.

However, as described above, when the ice making machine shifts to the de-icing operation, the solenoid valve 44 is closed, and if the de-icing operation is continued as it is, the pressure at the outlet side of the compressor 30 is reduced. May greatly increase. In this case, a load may be applied to the compressor 30 to lower the capacity, and an accident such as burnout or breakage may occur.

[0010]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned drawbacks inherent in a refrigerant circuit of an ice maker and the like according to the prior art, and has been proposed in order to preferably solve the problem. It is an object of the present invention to provide means capable of preventing a decrease in the capacity of a compressor or the occurrence of burnout when removing ice grown on an ice making plate or the like by flowing a vaporized refrigerant (hot gas).

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and to appropriately achieve the intended purpose, a refrigerant circuit of an ice making machine or the like according to the present invention comprises a high-pressure / high-temperature compressor compressed by a compressor. Is supplied to the condenser through the solenoid valve, the liquefied refrigerant condensed by the condenser is supplied to the expansion means, and the refrigerant expanded and vaporized through the expansion means is supplied to the evaporator. A refrigeration circuit for returning the vaporized refrigerant whose temperature has increased due to heat exchange to the compressor, and a high-pressure, high-temperature vaporized refrigerant from the compressor, which is branched and supplied to the evaporator via a hot gas valve, A hot gas circuit for performing de-icing in the evaporator; and opening the solenoid valve and closing the hot gas valve during the freezing operation, and opening the hot gas valve when the operation shifts to de-icing operation. In an ice maker or the like in which a valve is closed, the compression Interposed and between the electromagnetic valve, a pressure sensing means for opening and closing control during deicing like operation prior SL solenoid valve
Then, on the outlet side of the condenser, a low ambient temperature was detected.
The solenoid valve is closed only when shifting to deicing operation.
Temperature sensing means for controlling the ambient temperature is low.
A predetermined time after shifting to the deicing operation.
A timer for controlling the solenoid valve to open after a lapse of time
Is provided in the control circuit .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of a refrigerant circuit of an ice maker and the like according to the present invention will be described with reference to the accompanying drawings. In the refrigeration circuit and the hot gas circuit shown in FIG. 5, the same members as those already described are designated by the same reference numerals. FIG. 1 shows a refrigerant circuit according to a preferred embodiment of the present invention,
Although used in the flow-down ice maker described with reference to FIG. 3, it can also be used in general refrigerators that use hot gas to perform defrosting in an evaporator.

The refrigerant circuit shown in FIG. 1 is basically the same as the refrigerant circuit described with reference to FIG.
The difference is that a pressure switch 46 is provided between the solenoid valve 44 and the solenoid valve 44. That is, in the refrigerant circulation circuit according to the embodiment, the pipe 37 on the outlet side of the compressor 30 and the hot gas circuit 4
Upstream of the connection part C with the second pipe 38 in the flow direction of the refrigerant
The pressure switch 46 is interposed on the (compressor 30 side). This pressure switch 46 is in a state where the high-pressure and high-temperature refrigerant discharged from the compressor 30 is circulated to the hot gas circuit 42 by closing the electromagnetic valve 44 by the ice making machine shifting to the de-icing operation, When it is detected that the pressure on the outlet side of the compressor 30 has become equal to or higher than a preset pressure, control for opening the solenoid valve 44 is performed. The set pressure of the pressure switch 46 is set to a value that does not hinder efficient operation of the compressor 30.

That is, in the refrigerant circulation circuit, when the operation shifts from the ice making operation to the deicing operation, the hot gas valve 40 is opened and the electromagnetic valve 44 is closed to prevent the refrigerant from circulating in the refrigeration circuit 12 and the hot gas The hot gas is circulated through the circuit 42. Thereby, the ice making plate 10 attached to the evaporator 14,
10 is heated, the ice blocks 16 formed on the ice making plates 10 and 10 are released, and the ice blocks 16 are dropped by their own weight. It should be noted that the hot gas discharged from the compressor 30 during the deicing operation is entirely supplied to the hot gas circuit 42, and thus does not cause “stagnation” in the refrigeration circuit 12 as described above.
Further, it is possible to prevent a decrease in the deicing ability, shorten the time required for the deicing operation, and perform reliable deicing.

When the pressure switch 46 detects a preset pressure after the deicing operation is started, the solenoid valve 44 is opened. As a result, part of the hot gas discharged from the compressor 30 flows into the refrigeration circuit 12, and the pressure at the outlet side of the compressor 30 decreases. As a result, it is possible to prevent the occurrence of accidents such as a reduction in capacity due to overload of the compressor 30 and burning or breakage of the compressor 30. The flow of the hot gas into the refrigeration circuit 12 causes the compressor 3
When the pressure on the outlet side of “0” drops, the pressure switch 4
6 detects and closes the electromagnetic valve 44 to prevent the deicing ability from lowering.

Here, when the outside temperature is high as in summer,
A very large deicing capacity is not required. Conversely, when the outside air temperature is low, the deicing capacity is often insufficient. Therefore, when the ambient temperature is high (high temperature), the solenoid valve 44 is opened even during the deicing operation, and when the ambient temperature is low (low temperature), the solenoid valve 44 is opened during the deicing operation. By performing the closing control, efficient deicing can be performed at both high and low temperatures. Therefore, as shown in FIG. 2, a temperature sensing means 48 such as a thermostat is provided on the outlet side of the condenser 32, and only when the temperature sensing means 48 detects a low temperature, the operation is shifted to the deicing operation. It is recommended to perform control for closing the solenoid valve 44. The opening and closing of the solenoid valve 44 at the time of shifting to the deicing operation may be controlled by detecting the high pressure of the condenser 32.

In the deicing operation, a large amount of hot gas is circulated in the initial and middle stages, and the amount of circulation of the hot gas is reduced in the latter period, so that deicing can be performed satisfactorily when the ambient temperature is low. Is known from experiments and experience. Therefore, for example, a timer provided in a control circuit (not shown) controls the solenoid valve 44 to be opened after a lapse of a predetermined time from the shift to the deicing operation, and allows a part of the hot gas to flow to the refrigeration circuit 12. Thus, the hot gas circulation amount of the hot gas circuit 42 may be reduced. The compressor 3
With the change of the pressure at the outlet side of zero, the refrigerant temperature and the pipe 37
Therefore, it is also possible to dispose a temperature detecting means in the pipe 37 and detect the temperature change by the detecting means to control the opening of the electromagnetic valve 44.

[0018]

As described above, the refrigerant circulation circuit of the ice making machine or the like according to the present invention uses the pressure detecting means inserted between the compressor and the solenoid valve to detect the pressure at the outlet of the compressor. It is configured to detect and control the opening and closing of the solenoid valve. That is, when the pressure on the outlet side of the compressor becomes equal to or higher than the predetermined pressure during the deicing operation, the solenoid valve is opened to allow a part of the hot gas to flow to the refrigeration circuit to reduce the pressure. As a result, it is possible to prevent the occurrence of accidents such as a decrease in the capacity of the compressor, a burnout or a breakage occurring during the deicing operation. Also, if the temperature sensing means detects a low ambient temperature
The ambient temperature is controlled by closing the solenoid valve.
Efficient deicing at both high and low temperatures
Can do it. Furthermore, when the ambient temperature is low,
At the time of deicing operation, at a predetermined time after shifting to the deicing operation
After a time has elapsed, the timer is controlled to open the solenoid valve.
Circulate hot gas in the early and middle stages
In the second half, however, the amount of hot gas circulation should be reduced.
Thus, the deicing can be performed more favorably.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a refrigerant circuit according to a preferred embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a refrigerant circuit according to another embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a falling-down type automatic ice maker that scatters and supplies ice making water to a vertically erected ice maker to produce ice blocks.

FIG. 4 is a schematic configuration diagram of a refrigeration circuit according to a conventional technique suitably used for the automatic ice maker shown in FIG.

FIG. 5 is a schematic configuration diagram of another refrigeration circuit according to the related art.

[Explanation of symbols]

12 refrigeration circuit, 14 evaporator, 30 compressor, 32 condenser, 34 expansion valve 40 hot gas valve, 42 hot gas circuit, 44 solenoid valve, 46 pressure switch 48 temperature sensing means

Claims (1)

(57) [Claims] 1. A high-pressure and high-temperature vaporized refrigerant compressed by a compressor (30) is supplied to a condenser (32) via an electromagnetic valve (44), and the liquefied refrigerant condensed by the condenser (32) is supplied. Is supplied to the expansion means (34), and the refrigerant expanded and vaporized through the expansion means (34) is evaporated.
(14), a refrigeration circuit (12) for returning the vaporized refrigerant whose temperature has increased by heat exchange in the evaporator (14) to the compressor (30).
The high-pressure and high-temperature vaporized refrigerant from the compressor (30) is branched and supplied to the evaporator (14) via a hot gas valve (40) to remove deicing and the like in the evaporator (14). A hot gas circuit (42) for performing the cooling operation.When the operation is freezing, the solenoid valve (44) is opened and the hot gas valve (40) is closed. ) open solenoid valve (in ice machine or the like so as to close the 44), between the compressor (30) solenoid valve (44), before SL solenoid valve (44)
Pressure detection means for opening and closing control during deicing like operation (46)
Interposed, at the outlet side of the condenser (32), low ambient temperature was detected
Only in this case, the solenoid valve (44) is
A temperature sensing means (48) for controlling closing is provided, and when the ambient temperature is low, the operation shifts to the deicing operation.
After a lapse of a predetermined time, the solenoid valve (44) is opened.
A refrigerant circuit for an ice maker or the like, wherein a timer for controlling the refrigerant circuit is provided in the control circuit.