JPH10103834A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize temperature of a load unit. SOLUTION: A branch forward refrigerant tube 8a for branching to a forward refrigerant tube 8 is connected to a load unit of a display case 2, while a branch return refrigerant tube 9a for branching to a return refrigerant tube 9 is connected to the unit of the case 2, and brine liquid is circulated. A temperature sensitive cylinder 19 of a temperature type three-way control valve 18 outputs a signal to a three-way control valve 21 via a capillary tube 20 in response to a deviation amount of an indoor temperature from a set temperature. The valve 21 previously decides a flow rate ratio of a flow rate in a direction (a) to that in a direction (b), increases or decreases an opening in the directions (a) and (b) to supply the liquid at a predetermined flow rate, thereby suppressing a change of the flow rate of the liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating apparatus that efficiently supplies cold heat from a refrigerator to a plurality of load units such as showcases.

[0002]

2. Description of the Related Art For example, in a supermarket or the like, a brine is often supplied from a refrigerator to a plurality of showcases serving as load units.

FIG. 5 shows a configuration diagram in the above case. A plurality of showcases 2 are arranged for a brine type refrigerator 1. The brine type refrigerator 1 includes a compressor 3, a condenser 4, a heat exchanger 5, and the like to form a refrigeration cycle. The heat exchanger 5 includes an evaporator 6 for evaporating Freon gas as a primary refrigerant on a primary side. On the secondary side, there is provided a heat exchanger 7 for flowing a brine liquid which exchanges heat with the evaporator 6.

The heat exchanger 5 of the brine type refrigerator 1 has a pump 10 connected to the outward refrigerant pipe 8 and the return refrigerant pipe 9, and a pump 10 disposed in the outward refrigerant pipe 8. The outward refrigerant pipe 8a is connected to a heat exchanger (not shown) of the showcase 2, while the branch return refrigerant pipe 9a branched to the return refrigerant pipe 9 is connected to the heat exchanger of the showcase 2 to circulate the brine liquid. It has become.
A first solenoid valve 11 is disposed on the branch outward refrigerant pipe 8a, and a second solenoid valve 12 is disposed between the branch outward refrigerant pipe 8a and the branch return refrigerant pipe 9a.
The opening and closing of the first and second solenoid valves 12 is controlled by a temperature controller 14 connected to a thermostat 13 provided in the showcase 2.

The temperature controller 14 fully opens the first solenoid valve 11 and fully closes the second solenoid valve 12 in accordance with the internal temperature of the thermostat 13, and supplies the brine to the showcase 2. The first solenoid valve 11 is fully closed, and the second solenoid valve 1
2 is fully opened to adjust the temperature in the refrigerator to a predetermined temperature by bypassing the brine solution.

FIG. 6 is a diagram for explaining control of a conventional brine type refrigerator. In the brine type refrigerator 1, a thermostat 15 is provided on the inlet side of the heat exchanger 7 on the secondary side of the heat exchanger 5. The temperature controller 16 is disposed to detect the temperature of the brine liquid in the return refrigerant pipe 9, and the temperature controller 16 controls the plurality of compressors 3. In this control, all or some of the plurality of compressors 3 are operated or stopped according to the temperature of the brine, so as to correspond to the load on the showcase 2.

A balance valve 17 is provided in the branch outgoing refrigerant pipe 8a in correspondence with the showcase 2 so as to correspond to the magnitude of the load on the showcase 2 so as to reduce poor cooling due to shortage of the brine liquid flow rate. .

[0008]

In a supermarket or the like, dozens of showcases 2 shown in FIG. 5 are often connected, and the first solenoid valve 11 and the second solenoid valve 12 are fully opened. If the fully closed state is repeated, the flow rate of the brine liquid circulating in the outward refrigerant pipe 8 and the return refrigerant pipe 9 may fluctuate, and it may be difficult to maintain a good internal temperature of the showcase 2.

In such a case, the balance valve 17 shown in FIG. 6 is adjusted so as to correspond to each showcase 2 in order to prevent a fluctuation in the flow rate of the brine liquid flowing through the outward refrigerant pipe 8 and the return refrigerant pipe 9. , The trouble is great, and
The adjustment of the balance valve 17 alone could not sufficiently suppress the fluctuation of the flow rate of the brine solution.

Further, conventionally, the pump 10 for feeding the brine and the compressor 3 for operating the refrigeration cycle are operated separately. When the pump 10 is stopped, the compressor 3 operates and heat is not sufficiently exchanged. There were problems such as the refrigerant returning to the compressor 3.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a refrigeration apparatus which can suppress the fluctuation of the flow rate of the brine when supplying the brine to a plurality of load units and can stably maintain the temperature of each load unit.

[0012]

According to the first aspect of the present invention, there is provided an evaporator having a heat exchanger for exchanging heat with an evaporating refrigerant and a supplied brine to cool the brine, a compressor, and a condenser. And a pump provided in one of the outward refrigerant pipe and the return refrigerant pipe connected to the heat exchanger, and a branch return refrigerant pipe branched to the outward refrigerant pipe and a return refrigerant pipe branched to the outward refrigerant pipe. And a plurality of load units connected to supply the brine liquid in correspondence with each other, and a branch outgoing refrigerant pipe to a corresponding load unit corresponding to the detected temperature of each load unit corresponding to each of the plurality of load units. Control means for controlling a supply flow rate for flowing the brine liquid and a bypass flow rate for flowing the brine liquid through a bypass pipe that bypasses the branch outward refrigerant pipe and the branch return refrigerant pipe. In the refrigerating apparatus provided, the control means controls the opening degree so as to increase or decrease the flow rate of the brine liquid at a ratio between a predetermined supply flow rate and a bypass flow rate according to a deviation between a detected temperature of each load unit and a set temperature. A temperature type three-way water control valve is provided. According to this means, the bypass flow rate and the supply flow rate are increased or decreased according to the temperature of each load unit. Therefore, even if the pressure loss of the internal piping of the showcase differs, the flow rate of the brine in each showcase is appropriately adjusted, and the temperature of the load unit can be maintained stably. Further, it can be realized economically with a simple configuration.

According to a second aspect of the present invention, there is provided a refrigerator including a heat exchanger for exchanging heat with the supplied refrigerant to cool the brine and cooling the brine, a compressor having a compressor, and a condenser. A pump is provided in one of the outward refrigerant pipe and the return refrigerant pipe connected to the heat exchanger, and a branch outward refrigerant pipe that branches to the outward refrigerant pipe and a branch return refrigerant pipe that branches to the return refrigerant pipe correspond to each other. A plurality of load units connected to supply the brine liquid, and a supply of the brine liquid flowing to the corresponding load unit corresponding to each of the plurality of load units in accordance with the detected temperature of the respective load units via a branch outward refrigerant pipe. A refrigerating apparatus having a control unit for controlling a flow rate and a bypass flow rate for flowing a brine liquid in a bypass pipe that bypasses a branch outward refrigerant pipe and a branch return refrigerant pipe. Oite, a pressure sensor for detecting an intake pressure of the compressor, the pressure detection signal from the pressure sensor is obtained by so providing the pressure controllers for controlling the compressor to a predetermined setting signal. According to this means,
Even if the flow rate supplied to the evaporator changes, the suction pressure of the compressor is maintained at a predetermined value, and stable refrigeration heat can be supplied to a plurality of load units, and operation with reduced power consumption can be performed. .

According to a third aspect of the present invention, there is provided the refrigeration system according to the first or second aspect, wherein a means for preventing the compressor from starting when the pump for supplying the brine to each load unit is stopped is provided. It was done. According to this means, while the pump for supplying the brine is stopped, it is possible to prevent the compressor from being started and return the refrigerant gas that does not exchange heat with the brine to the compressor.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a refrigerating apparatus showing a first embodiment of the present invention. A brine type refrigerating machine 1 has a compressor 3, a condenser 4, a heat exchanger 5, etc. A cycle is formed, and the heat exchanger 5 includes, on the primary side, an evaporator 6 for evaporating Freon gas as a primary refrigerant, and a heat exchanger 7 for flowing a brine liquid for heat exchange with the evaporator 6 and cooling the brine liquid on the secondary side. It has.

The heat exchanger 7 of the brine type refrigerator 1 connects a forward refrigerant pipe 8 and a return refrigerant pipe 9, has a pump 10 disposed in the forward refrigerant pipe 8, and branches to the forward refrigerant pipe 8. The refrigerant pipe 8a is connected to the load unit of the showcase 2 while the branch return refrigerant pipe 9a branched to the return refrigerant pipe 9 is connected to the load unit of the showcase 2 so as to circulate the brine liquid.

Between the branch outgoing refrigerant pipe 8a and the branch return refrigerant pipe 9a, a temperature type three-way water control valve 18 is provided corresponding to the showcase 2, and the temperature type three-way water control valve 18 is a temperature sensing part. 19, capillary tube 20 and three-way control valve 2
And 1. In the temperature sensing section 19, the capillary tube 20 is set in accordance with the amount of deviation between the internal temperature and the set temperature.
A signal is output to the three-way water control valve 21 through the
In 1, the flow ratio between the a direction and the b direction is predetermined, and the opening degree in the a direction and the b direction is increased or decreased so as to flow a predetermined flow according to the deviation amount from the capillary tube 20.

As shown in FIG. 2, the temperature type three-way water control valve 18 has a predetermined flow rate (vertical axis) with respect to the magnitude of the valve opening temperature deviation (horizontal axis) between the temperature sensing part temperature and the set temperature. ) Is obtained by opening the three-way water control valve 21 by a predetermined opening degree, and the ratio between the a-direction (supply amount) and the b-direction (bypass amount) is, for example, 60% in the a direction and 40% in the b direction. Can be adjusted appropriately.

When controlled by the temperature type three-way water control valve 18, the flow rate is increased or decreased in accordance with the temperature deviation and controlled. Therefore, even if the pressure loss of the internal piping of the showcase is different,
The flow rate of the brine solution in each showcase is adjusted appropriately,
The inside temperature of each showcase 2 can be stably maintained. Further, the balance valve 17 which has been conventionally required can be omitted.

FIG. 3 is a block diagram of a refrigerating apparatus showing a second embodiment of the present invention. The brine type refrigerator 1 is provided with a pressure sensor 23, and based on a pressure detection signal of the pressure sensor 23. Thus, the compressor 3 is controlled by the pressure controller 24.

The pressure sensor 23 is connected to the evaporator 6 of the heat exchanger 5.
, That is, the refrigerant gas suction pressure on the inlet side of the compressor 3, and outputs a pressure detection signal to the pressure controller 24. The pressure controller 24 changes the frequency of the inverter or the like according to the deviation between the predetermined pressure setting signal and the pressure detection signal, and increases or decreases the discharge amount of the compressor 3. Reference numeral 22 denotes an expansion valve.

With this configuration, the suction pressure on the inlet side of the compressor 3 is controlled to a predetermined pressure, and fluctuations in the amount of refrigerating heat supplied to the evaporator 6 of the heat exchanger 5 are suppressed. Accordingly, compared with the conventional method of controlling the compressor 3 in accordance with the temperature of the brine, the amount of freezing heat from the brine type refrigerator 1 to the showcase 2 is not affected by the fluctuation of the flow rate of the brine. Can be supplied stably in a predetermined amount. In addition, by keeping the suction pressure constant, it is possible to improve the operating efficiency of the refrigerator having a direct relationship with the suction pressure.

The capacity control is not limited to the control by the inverter, and any one of the plurality of compressors 3 is stopped according to the pressure detection signal to stop the operation of the compressor 3 to a predetermined value. You may.

FIG. 4 is a diagram showing a processing procedure for starting the compressor 3 according to the third embodiment of the present invention.

As shown, when a start command signal is input to the compressor 3 in the configuration of FIGS. 1 and 3, it is detected whether the brine pump 10 is operating or stopped (S1, S1).
2) And the compressor 3 is started only while the pump 10 is operating (S3).

With this configuration, it is possible to prevent the compressor 3 from starting while the pump 10 is stopped, and to prevent troubles such as returning refrigerant gas that is not sufficiently exchanged by the heat exchanger 5 to the compressor 3. 3 can be prevented. In the process of FIG. 4, the compressor 3 may be started after a predetermined time has elapsed since the operation of the pump 10 was detected.

[0028]

As described above, according to the first aspect of the present invention, since the bypass flow rate and the supply flow rate are increased or decreased according to the temperature of each load unit, the brine liquid is appropriately supplied to each showcase having a different pressure loss. Supply can be performed, the temperature of the load unit can be stably maintained, and economical with a simple configuration.

According to the second aspect of the present invention, since the suction pressure of the compressor is maintained at a predetermined value, stable refrigeration heat can be supplied to a plurality of load units, and efficient operation can be performed.

According to the third aspect of the invention, while the pump for supplying the brine is stopped, it is possible to prevent the compressor from being started and return the refrigerant gas to the compressor.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a refrigeration apparatus showing a first embodiment of the present invention.

FIG. 2 is an explanatory view showing an operation of a temperature type three-way water control valve provided in the refrigeration apparatus of FIG.

FIG. 3 is a configuration diagram of a refrigeration apparatus showing a second embodiment of the present invention.

FIG. 4 is a flowchart showing a processing procedure when starting a compressor according to a third embodiment of the present invention.

FIG. 5 is a configuration diagram showing a conventional refrigeration apparatus.

FIG. 6 is another configuration diagram showing a conventional refrigeration apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blind refrigerator 2 Showcase 3 Compressor 4 Condenser 5, 7 Heat exchanger 6 Evaporator 8 Outgoing refrigerant piping 8a Branch outgoing refrigerant piping 9 Returning refrigerant piping 9a Branching returning refrigerant piping 10 Pump 18 Temperature three-way water control valve 19 Temperature sensing part 20 Capillary tube 21 Three-way water control valve 23 Pressure sensor 24 Pressure controller

Claims (3)

[Claims] An evaporator having a heat exchanger for exchanging heat with an evaporating refrigerant and a supplied brine to cool the brine, a refrigerator including a compressor and a condenser, and the heat exchanger A pump is provided in one of the outgoing refrigerant pipe and the outgoing refrigerant pipe connected to the refrigerant pipe, and a branch outgoing refrigerant pipe branched to the outgoing refrigerant pipe and a branched return refrigerant pipe branched to the return refrigerant pipe are respectively associated with the brine liquid. A plurality of load units connected so as to supply the supply flow rate for flowing the brine liquid through the branch outward refrigerant pipe to the corresponding load unit corresponding to the detected temperature of each load unit corresponding to each of the plurality of load units. A refrigeration system having a control means for controlling a bypass flow rate for flowing a brine liquid in a bypass pipe that bypasses the branch outward refrigerant pipe and the branch return refrigerant pipe. In the apparatus, the control means controls the opening degree so as to increase or decrease the flow rate of the brine liquid at a predetermined ratio between the supply flow rate and the bypass flow rate according to a deviation between the detected temperature of each load unit and a set temperature. A refrigeration apparatus comprising a three-way temperature control valve. 2. A refrigerator comprising a heat exchanger for cooling the brine by exchanging heat with the evaporating refrigerant and the supplied brine, a refrigerator comprising a compressor and a condenser, and the heat exchanger. A pump is provided in one of the outgoing refrigerant pipe and the outgoing refrigerant pipe connected to the refrigerant pipe, and a branch outgoing refrigerant pipe branched to the outgoing refrigerant pipe and a branched return refrigerant pipe branched to the return refrigerant pipe are respectively associated with the brine liquid. A plurality of load units connected so as to supply the supply flow rate for flowing the brine liquid through the branch outward refrigerant pipe to the corresponding load unit corresponding to the detected temperature of each load unit corresponding to each of the plurality of load units. A refrigeration system having a control means for controlling a bypass flow rate for flowing a brine liquid in a bypass pipe that bypasses the branch outward refrigerant pipe and the branch return refrigerant pipe. A refrigerating apparatus comprising: a pressure sensor for detecting a suction pressure of the compressor; and a pressure controller for controlling the compressor so that a pressure detection signal from the pressure sensor becomes a predetermined setting signal. 3. The apparatus according to claim 1, further comprising means for preventing the compressor from starting when the pump for supplying the brine to each of the load units is stopped.
A refrigeration device as described.