JPH0799303B2 - Ice making equipment - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ice making device that produces a slurry-like iced substance such as water and stores it in an ice storage tank, and particularly relates to measures for improving performance. .

(Prior Art) Conventionally, for example, as disclosed in Japanese Utility Model Laid-Open No. 1-144722, a water circulation path for circulating water in an ice storage tank between a heat exchanger and an ice storage tank provided in a refrigerant circuit. In the ice making device in which the water in the ice storage tank is turned into slurry ice by heat exchange with the refrigerant in the refrigerant circuit, the water is opened in the outlet side of the water circulation path to store the water in the supercooled state. The ones that drop ice into a slant gutter installed at a certain height above the water surface of the water tank, ice the water into a slurry while passing through this slant gutter, and store iced substances in the ice storage tank below This is a known technique.

Further, in the same publication, by providing a supercooling zone for further subcooling water by using the refrigerant or the like of the refrigerant circuit in the middle of the inclined trough, the supercooled state of water is eliminated and ice formation is caused. It is also disclosed.

(Problems to be Solved by the Invention) However, when a supercooling elimination section for eliminating a supercooled state of water is provided above the ice storage tank as in the conventional one,
There is a problem in that a space for that is required, design constraints become large, and once the water is exposed to the air, cold heat is released into the air, resulting in a large heat loss.

Therefore, by setting the water circulation path as a closed circuit, a supercooled state is produced in the water in the water circulation path, and the supercooled state is eliminated to generate a slurry-like iced substance, which is circulated in the ice storage tank. It is possible to avoid design restrictions and heat loss.

Further, as a means for eliminating the supercooled state of water, it is conceivable to provide a means for cooling the water in the supercooled state by utilizing the refrigerant in the refrigerant circuit, as in the conventional device.

However, since the above-mentioned conventional publication does not specifically disclose means for cooling the middle of the inclined gutter, it is unclear what action can be taken to eliminate the cooled state. Further, since the specific configuration when the heat exchanger and the refrigerant circuit that share the supercooled state are shared is unknown, it may not be possible to obtain the effect for eliminating the supercooled state as it is. .

INDUSTRIAL APPLICABILITY According to the present invention, by supercooling water or the like which is further cooled to a temperature lower than that temperature, the diameter of buds of ice crystals that grow and disappear in the supercooled water grows. Paying attention to the fact that the probability of reaching the predetermined critical diameter that is sufficient to reach the temperature will increase, and measures will be taken to lower the evaporation temperature of the refrigerant bypassed from the refrigerant circuit to the cooling heat exchanger than the heat exchanger side. Thus, the supercooled state of water or the like supercooled by the heat exchanger can be promptly eliminated, and the performance of the ice making device can be improved.

(Means for Solving the Problem) In order to achieve the above object, the first means for solving the problems is to store a slurry of iced water or an aqueous solution in an ice making device as shown in FIG. The ice making tank (5), a main heat exchanger (22) for supercooling water or an aqueous solution, and a pipe member having a closed ring-shaped cross section, the main heat exchanger (22)
And a water circulation furnace (51) for forcibly circulating water or an aqueous solution between the ice making tank (5) and the main heat exchanger (51) arranged in the water circulation path (51) on the downstream side of the main heat exchanger (22). A sub heat exchanger (8) for recooling to a lower temperature state so as to eliminate the supercooled state of the water or aqueous solution supercooled in 1), and the main heat exchanger serving as a compressor, a condenser and an evaporator. Pressure loss to the passing refrigerant which is arranged in the closed circuit refrigerant circuit (1) in which (22) are sequentially connected and the gas line serving as the outlet side pipe of the main heat exchanger (22) of the refrigerant circuit (1). The decompressing means for supplying the refrigerant and the sub-heat exchanger (8) serving as an evaporator by bypassing the main heat exchanger (22) and the decompressing means between the liquid line and the gas line of the refrigerant circuit (1). A bypass path (81) connected via the above is provided, and the evaporation temperature of the refrigerant in the sub heat exchanger (8) is It is obtained by a configuration to be lower than the evaporation temperature of the refrigerant in the serial main heat exchanger (22).

A second solving means is the above first solving means, wherein an accumulator (Ac) is provided in the gas line in the refrigerant circuit (1) and the depressurizing means is constituted by this accumulator (Ac).

(Operation) With the above configuration, in the invention of claim (1), the decompression means (C ₄ ) is provided in the auxiliary heat exchanger (8) in the return conduit (51B) downstream of the main heat exchanger (22). Water or the like is cooled by heat exchange with the refrigerant bypassed from the liquid line of the refrigerant circuit (1) via the.

In this case, since water and the like have already been supercooled by the main heat exchanger (22), it is necessary to cool the water to a lower temperature in order to eliminate this supercooled state. Here, in the present invention, the sub heat exchanger (8) is provided in the cooling bypass passage (81) for bypassing the refrigerant from the liquid line of the refrigerant circuit (1), and the sub heat exchanger (8) and the main heat The exchanger (22) means that the liquid line and the gas line of the cooling circuit (1) are connected in parallel with each other, and the pressure of the refrigerant is added to the gas line on the main heat exchanger (22) side. A pressure reducing means for giving a loss is provided, and the evaporation temperature of the refrigerant in the sub heat exchanger (8) is kept lower than the evaporation temperature of the refrigerant in the main heat exchanger (22). Therefore, in the sub heat exchanger (8), water or the like in a supercooled state is further cooled to a lower temperature, the supercooled state is eliminated, and it is frozen into a slurry.

According to the invention of claim (2), in the invention of claim (1), an accumulator (Ac) is provided in the gas line of the cooling circuit (1), and the accumulator (Ac) is the main heat exchanger (Ac). Since it functions as a pressure reducing means for the flow of the refrigerant on the 22) side, the evaporation temperature of the sub heat exchanger (8) is kept lower than the evaporation temperature of the main heat exchanger (22), and a means for separately providing a pressure loss is provided. Claim (1) above without provision
The effect of the invention can be obtained.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings starting from FIG.

FIG. 2 shows the configuration of the refrigerant circuit (1) of the air conditioner of the first embodiment, where (11) is the first compressor and (12) is the discharge side of the first compressor (11). An outdoor heat exchanger for exchanging heat between the refrigerant and the outdoor air, (13) the heat exchanger (12)
Is an outdoor electric expansion valve that adjusts the refrigerant flow rate or reduces the pressure, and the above-mentioned devices (11) to (13) are connected in series in the first conduit (14).

Further, (21) is the second compressor, (22) is the second compressor (2
A water heat exchanger, which is arranged on the discharge side of 1) and is a main heat exchanger for supercooling water or an aqueous solution in a water storage tank (5) described later, and (23) is a water heat exchanger (22). A water-side electric expansion valve that regulates the flow rate of the refrigerant when functioning as a condenser, and decompresses the refrigerant when functioning as an evaporator, and each of the devices (21) to (23) is a second conduit (24). Are connected in series inside.

Note that (SD ₁ ) and (SD ₂ ) are each compressor (11),
Oil separator provided in the discharge pipe of (21), (C ₁ ), (C ₂ )
From the oil separators (SD ₁ ) and (SD ₂ ) to the compressors (11) and
Oil return pipes (R) provided on the suction side of (21)
It is a capillary tube for decompression, which is provided in each of T ₁ ) and (RT ₂ ).

Further, (32) and (32) are indoor heat exchangers arranged in each room, and (33) and (33) are indoor electric expansion valves as pressure reducing valves for reducing the pressure of the refrigerant, and the above-mentioned devices (32). ) And (33) are connected in series, and each set is connected in parallel in the third conduit (34).

The first pipeline (14) and the second pipeline (24) are the third
It is connected in parallel to the pipe line (34). Note that (A
c) is an accumulator provided in the third conduit (34) on the suction side of each compressor (11), (21).

Further, (2) includes a gas pipe of the outdoor heat exchanger (12) and gas pipes of the indoor heat exchangers (32) and (32) in the compressors (11) and (2
A four-way switching valve (2) which is switched so as to alternately communicate with the discharge side or the suction side of 1), and when the four-way switching valve (2) is switched to the solid line side in the figure, the outdoor heat exchanger (12 ) Functions as a condenser and the indoor heat exchangers (32) and (32) function as evaporators to perform indoor cooling operation, while the four-way switching valve (2) switches to the side of the broken line in the figure, the outdoor heat The exchanger (12) functions as an evaporator, and the indoor heat exchangers (32), (32) function as condensers to perform indoor heating operation.

Further, the gas pipe of the water heat exchanger (22) and each compressor (1
Branch path (2) that bypass-connects the suction pipes of 1) and (21)
5) and the gas pipe of the water heat exchanger (22) to the second compressor (2
A water side switching valve (26) for alternately communicating with the discharge pipe of 1) and the branch passage (25) is provided. The water side switching valve (26)
Uses three ports of the four-way switching valve, and when the water side switching valve (26) is switched to the solid line side in the figure, the gas pipe of the water heat exchanger (22) has a branch path (25). Side, that is, communicating with the suction side of each compressor (11), (21), the water heat exchanger (22) functions as an evaporator, while the water side switching valve (26) is switched to the broken line side in the figure. Sometimes the gas pipe of the water heat exchanger (22) communicates with the discharge pipe of the second compressor (21), and the water heat exchanger (22)
Is designed to function as a condenser. In addition,
(C ₃ ) is a capillary tube provided in the pipe on the dead port side of the water side switching valve (26).

Furthermore, a bypass passage (3) for connecting the discharge pipes of the first compressor (11) and the second compressor (21) is provided,
A check valve (4) which allows only refrigerant flow from the discharge pipe side of the second compressor (21) to the discharge pipe side of the first compressor (11) is provided in the bypass passage (3). There is.

That is, when the outdoor heat exchanger (12) and the water heat exchanger (22) function as condensers, when the condensation concentration in the water heat exchanger (22) is high and the pressure is high, the second compressor (21 )
The discharged gas is discharged to the outdoor heat exchanger (12) side so that the heat radiation amount can be distributed.

Here, the air conditioner is provided with an ice storage tank (5) for storing a slurry iced product of water or an aqueous solution as a heat storage medium, and the water storage tank (5) and the water heat exchanger. A water circulation path (51) is connected to the (22) so that water or an aqueous solution can circulate. The water circulation path (51) includes a forward path (51A) for supplying water and the like from the bottom of the ice storage tank (5) to the water heat exchanger (22), and an ice storage tank (22) from the water heat exchanger (22). 5)
Return conduit (51
B) and is configured to forcibly circulate the water or aqueous solution in the ice storage tank (5) in the water circulation path (51) by the pump (52) provided in the reciprocating path (51A). .

Then, the pump (5) of the forward path (51A) of the water circulation path (51)
On the downstream side of 2), a strainer (53) for removing solid matters such as iced matter and dust in the water or aqueous solution of the water circulation path (51) is provided, and further on the downstream side of the strainer (53). Is
A preheat heat exchanger (6) for preheating water or the like supplied to the water heat exchanger (22) is provided. On the other hand, the liquid line of the refrigerant circuit (1) is provided with a preheating bypass passage (61) for flowing a part of the liquid refrigerant to the preheat heat exchanger (6) by bypassing the water side electric expansion valve (23). On the downstream side of the preheat heat exchanger (6) in the preheat bypass passage (61), a preheat electric expansion valve (62) having a refrigerant decompression function and a flow rate control function is provided. The preheat electric expansion valve (62) and the water side electric expansion valve (23) adjust the refrigerant flow rate of the preheat bypass passage (61) and reduce the pressure of the refrigerant during the ice making operation of the water heat exchanger (22). Is also supposed to do.

Further, in the return pipe (51B) of the water circulation passage (51), the water or the like in the return pipe (51B) is cooled to the downstream side of the water heat exchanger (22) to cool the water heat exchanger (22). Is provided with a recooler (8) as a sub-heat exchanger for eliminating a supercooled state of water or the like supercooled by the subcooler, and further between the recooler (8) and the water heat exchanger (22). The heat insulation heat exchanger (7) is provided in the as a freezing progress preventing unit for preventing the freezing of the return conduit (51B) from progressing to the water heat exchanger (22).

Here, the liquid line of the refrigerant circuit (1) and each compressor (1
A recooling bypass passage (81) is provided between the branch passage (gas line) on the suction side of 1) and (21) to allow the refrigerant to flow by bypassing the water heat exchanger (22). The recooling bypass passage (81) is provided with the recooling capillary tube (C ₄ ) and the recooler (8) in this order from the upstream side. That is, a low-temperature refrigerant whose pressure has been reduced by the re-cooling capillary tube (C ₄ ) is circulated in the re-cooling device (8), and the water and the like supercooled in the water heat exchanger (22) are exchanged by heat exchange with this refrigerant. It is designed to recool.

In that case, the gas side pipe of the water heat exchanger (22) is connected to the branch passage (25) through the water side switching valve (26), while the gas side of the recooler (8) is directly branched ( By communicating with the water side switching valve (26), pressure loss is caused in the water heat exchanger (22) by the passage of the water side switching valve (26), and the evaporation temperature of the recooler (8) is changed to the water heat exchanger. The temperature is maintained lower than that of (22), and the water and the like supercooled by the water heat exchanger (22) can be further cooled by the recooler (8).

A heat insulation bypass passage (71) is provided to bypass the liquid refrigerant from the liquid line of the refrigerant circuit (1) to the heat insulation heat exchanger (7) and return it to the liquid line. In the heat exchanger (7), the return conduit (51B) is heated by heat exchange with the liquid refrigerant in the liquid line, and the supercooling of water or the like is eliminated in the recooler (8) or the return conduit (51B). It is designed to prevent the frost formed by the above from adhering to the pipe wall of the return pipe (51B) and freezing to the water heat exchanger (22).

The four-way switching valve (2) is switched to the solid line side in the figure when the air-conditioning apparatus is operating and the indoor cooling operation is performed. When the water side switching valve (26) is switched to the solid line side in the figure, after the refrigerant discharged from each of the compressors (11) and (21) has been condensed in the outdoor heat exchanger (12). , The indoor heat exchangers (32) and (32) evaporate to cool the room. When the water side switching valve (26) is switched to the broken line side in the figure, the refrigerant discharged from the first compressor (11) flows to the outdoor heat exchanger (12), while the second compressor (21). The discharged refrigerant flows into the water heat exchanger (22), is condensed and circulates so as to evaporate in the heat exchangers (32) and (32) of the chambers.

Further, when electric power is cheap at night or the like, a cold storage operation for storing cold heat in the ice storage tank (5) is performed. That is, the four-way switching valve (2) and the water side switching valve (26) are switched to the solid line side in the figure, the indoor electric expansion valves (33) and (33) are closed, and the compressors (11) and (21) are closed. ) Is condensed in the outdoor heat exchanger (12) and then decompressed by the water side electric expansion valve (23) (or preheat electric expansion valve (62)) to be evaporated by the water heat exchanger (22). Thus, the water or the aqueous solution in the ice storage tank (5) is supercooled to be iced, and cold heat is stored in the ice storage tank (5).

Therefore, in the present embodiment, during the ice making operation in the above embodiment, the water heat exchanger (22) is supercooled in the return pipe (51B) on the downstream side of the water heat exchanger (main heat exchanger) (22). The water or the like is recooled by the recooler (sub heat exchanger) (8).

In that case, in order to eliminate the supercooled state of water or the like supercooled by the water heat exchanger (22) by recooling, it is necessary to cool it to a lower temperature. Here, in the present invention, the refrigerant bypassed to the recooler (8) is bypassed from the liquid line of the refrigerant circuit (1), and the recooler (8) and the ice heat exchanger (22) are Are connected in parallel to each other across the liquid line and the gas line of the refrigerant circuit (1), and
The gas side pipe of the water heat exchanger (22) is provided with a water side switching valve (26) serving as a pressure reducing means. Therefore, the gas refrigerant on the side of the water heat exchanger (22) passes through the water side switching valve (26) to cause a pressure loss, and the recooler (8) correspondingly.
The evaporation temperature of the refrigerant in is kept lower than the evaporation temperature of the refrigerant in the water heat exchanger (22).

That is, in the recooler (8), water or the like in a supercooled state is further cooled to a lower temperature, the supercooled state is eliminated, and the water is slurried. Therefore, a smooth ice-making operation can be obtained, and the performance of the ice-making device can be improved.

Although the water side switching valve (26) is used as the pressure reducing means for giving a pressure loss in the above embodiment, a pressure reducing device such as a capillary tube may be separately provided. However, when the water side switching valve (26) is used as the pressure reducing means as in the above-described embodiment, it is possible to avoid an increase in cost because it is possible to use only existing equipment without providing a means for giving a pressure loss separately. it can.

Next, a second embodiment will be described. FIG. 3 shows the refrigerant piping system of the air conditioner in the second embodiment. In this embodiment, the refrigerant inlet end of the recooling bypass passage (81) has the refrigerant circuit (81) as in the first embodiment. ), And the refrigerant outlet end of the re-cooling bypass passage (81) is a suction pipe (gas line) downstream of the accumulator (Ac).
It is connected to the. The other structure is similar to that of the first embodiment.

That is, by connecting the refrigerant outlet end of the recooling bypass passage (81) to the gas line on the downstream side of the accumulator (Ac), the pressure due to the flow resistance of the accumulator (Ac) on the gas refrigerant on the water heat exchanger (22) side. This causes a loss and keeps the evaporation temperature in the recooler (8) lower than the evaporation temperature in the water heat exchanger (22). That is, the water heat exchanger (2
The decompression means that gives pressure loss to the refrigerant on the 2) side is configured.

Therefore, in the present embodiment, the refrigerant on the side of the water heat exchanger (22) gives a pressure loss due to the accumulator (Ac), so that the evaporation temperature of the recooler (8) corresponds to that of the water heat exchanger (22). Since the temperature is kept lower than the evaporation temperature, the performance of the ice making device can be improved without separately providing a means for giving a pressure loss.

In each of the above embodiments, the refrigerant circuit (1) has two compressors (11) and (21) connected in series to heat exchangers, respectively. It is needless to say that the present invention is not limited to such an embodiment and can be applied to a device provided with only one compressor.

(Effects of the Invention) As described above, according to the invention of claim (1), as an ice-making device, water is circulated in the water circulation path for forcibly circulating water or the like in the ice storage tank by heat exchange with the refrigerant in the refrigerant circuit. A main heat exchanger for supercooling etc. is provided, and a sub heat exchanger for recooling the supercooled water etc. to eliminate the supercooled state is arranged further downstream, and the sub heat exchanger is installed. The main heat exchanger of the refrigerant circuit is installed in a bypass line that is a parallel line, and pressure loss is applied to the gas refrigerant after passing through the main heat exchanger, so the evaporation temperature of the sub heat exchanger is It can be kept lower than the evaporation temperature of the main heat exchanger, and therefore the ice making action of eliminating the supercooled state of water etc. and making it into a slurry can be smoothly performed, and the performance of the ice making device is improved. Can be achieved.

In the invention of claim (2), the means for giving the pressure loss in the invention of the above-mentioned claim (1) uses the accumulator arranged on the suction side of the compressor, so that means for separately giving the pressure loss is provided. Therefore, the effect of the invention of claim (1) can be obtained, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. FIG. 2 is a refrigerant piping system diagram showing the configuration of the refrigerant circuit of the air conditioning apparatus in the first embodiment, and FIG. 3 is a refrigerant piping system diagram showing the configuration of the refrigerant circuit of the air conditioning apparatus in the second embodiment. 1 …… Refrigerant circuit 5 …… Water tank 8 …… Recooler (sub heat exchanger) 22 …… Water heat exchanger (main heat exchanger) 51 …… Water circulation path 81 …… Recooling bypass path 26 …… Water side switching valve (pressure reducing means) Ac …… Accumulator (pressure reducing means)

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yuji Nakazawa 1304 Kanaoka-machi, Sakai-shi, Osaka Daikin Industry Co., Ltd., Kanaoka factory, Sakai Manufacturing Co., Ltd.

Claims (2)

[Claims] 1. An ice making tank (5) for storing a slurry of iced water or an aqueous solution, a main heat exchanger (22) for supercooling water or an aqueous solution, and a closed ring cross section. A water circulation path (51) composed of a pipe member for forcibly circulating water or an aqueous solution between the main heat exchanger (22) and the ice making tank (5), and the main heat exchanger (22)
A sub heat exchanger (8) arranged in the water circulation path (51) on the downstream side and recooled to a lower temperature state so as to eliminate the supercooled state of the water or aqueous solution supercooled by the main heat exchanger (1).
And the main heat exchanger (22) that serves as a compressor, condenser, and evaporator.
A closed circuit refrigerant circuit (1) that is connected in sequence with a refrigerant circuit (1) and a gas line that is a gas line that serves as an outlet side pipe of the main heat exchanger (22) of the refrigerant circuit (1) and that causes pressure loss to the passing refrigerant. And the liquid line and the gas line of the refrigerant circuit (1) are connected via the main heat exchanger (22) and the depressurizing means and the auxiliary heat exchanger (8) serving as an evaporator. And a bypass passage (81) for performing cooling, the evaporation temperature of the refrigerant in the sub heat exchanger (8) being lower than the evaporation temperature of the refrigerant in the main heat exchanger (22). 2. The refrigerant circuit (1) according to claim (1), wherein an accumulator (A) is installed in a gas line.
c), wherein the depressurizing means is the accumulator (Ac).