JPS61191839A - Refrigerator unit functioning as f class and c3 class refrigerating facility in combination - 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] [Prior art] According to the Warehousing Act, if the refrigeration temperature is -25°C or less, 2.
Class 03 refrigeration equipment is defined as 03 class refrigeration equipment if the temperature is around 0°C.

By the way, conventionally, when trying to cool down F-class and 03-class refrigeration equipment with the same unit, the following problems arise.

If 03 class operation is the main purpose, a single-stage compression refrigerator is used to cover the entire temperature range, but the motor must be selected based on the shaft horsepower at 03 class operation.
During F-class operation, the motor is too large and cannot operate efficiently.

In other words, if class 2 operation is performed with a single-stage compression refrigerator, the operating cost will be higher than that of a two-stage compression refrigerator, and the contract power will be larger. The entire temperature range can be covered with just the refrigerator.

During class 03 operation, it is necessary to throttle the refrigerator using a suction pressure regulating valve to prevent overload, which reduces the operating efficiency of the refrigerator.Also, when operating a class C= with a 21-stage compression refrigerator, In this case, a larger amount of power will be required to produce the same refrigerating capacity than when a single-stage compression refrigerator is operated at class 03.

In particular, recently there has been an increase in cases where F class and 'C3 class are switched in the same cold room depending on the season or the movement of cargo, but F class is the main operation or 03 class is the main operation. As can be expected, with the conventional method, operating costs would be high and energy savings could not be expected.

[Object of the present invention]

The present invention has a two-stage compression refrigerator that performs F-class operation and a single-stage compression refrigerator that performs 03-class operation in the same unit, shares a condenser and liquid receiver, and operates over a wide temperature range in the same unit. By enabling cooling, the optimal operating condition can be selected depending on each temperature, and conventional F class and 0 class
The aim is to significantly reduce operating costs compared to class 3 units.

[Structure of the present invention] The refrigeration unit of the present invention that can be used for both F-class and 03-class refrigeration equipment has a condenser connected to each discharge side of a single-stage compression refrigerator and a multi-stage compression refrigerator using discharge pipes each having a switching valve. connect to
The liquid side of the condenser is connected to the inlet of the intercooler with a liquid feed pipe, the outlet of the intercooler is connected to the inlet of the cooler with a liquid feed pipe with an expansion valve, and the outlet of the cooler is connected to the inlet of the cooler with a liquid feed pipe having an expansion valve. The pipe is branched off from the pipe, each having a switching on-off valve, and connected to each suction side of the single-stage compression refrigerator and the multi-stage compression refrigerator at the branch return connection, and the opening and closing of each switching valve is controlled. By switching, the single-stage compression refrigerator or the multi-stage compression refrigerator is operated alternately.

[Example of the present invention]

An embodiment of the present invention will be described in detail below using a specific example shown in the attached drawings in which a two-stage compression refrigerator is used as a multi-stage compression refrigerator.

In the figure, the symbol IF is a two-stage compression refrigerator for F-class refrigeration.
The discharge side is connected to the inlet side of the condensate/liquid receiver B by a discharge pipe 7A via an oil separator 2F, an on-off valve 3F, and a check valve 4F.

The IC is a single-stage compression refrigerator for refrigeration at 031, and its discharge side is connected to the inlet side of the condensing house liquid receiver 6 via the oil separator 2C1 on-off valve 3C and check valve 4G by a discharge pipe 7B. There is.

Note that the oil separated by each oil separator 2G, 2F is returned to each refrigerator IC1IF from oil return pipes 18A, 18B.

On the other hand, the outlet side of the condensed liquid receiver 6 is connected to the cooling coil 3A of the intercooler 9 through a liquid sending pipe IB, and the outlet of the coil is connected to the cooling coil 3A of the intercooler 9 through a liquid sending pipe 18^ having an expansion valve 13. Connected to the inlet side, the return pipe 17 from the cooler xO is a branch return pipe 17F to the right of the switching valves 5F and 5C, respectively.
, 17G to each suction side of the two-stage compression refrigerator IF and the single-stage compression refrigerator IC.

Further, a return pipe 11 branches from the middle of the liquid sending pipe 18A, and this return pipe 11 is connected to the inlet side of the intercooler 8 via a solenoid valve 12 and an expansion valve 13, and is connected to the outlet side of the intercooler 8. is connected to the suction side of the two-stage compression refrigerator IF via a return pipe 11A. - Note that 14 is a controller, and 15 is a fan of the cooler 10. ' Next, the operation of this unit will be explained.

(1) When used as F-class refrigeration equipment, the refrigerator uses a two-stage compression refrigerator IF, with on-off valves 5C and 30 closed, and 5F and 3F open. As a result, the refrigerant gas from the two-stage compression refrigerator IF is transferred to the oil separator 2F, the condensation/liquid receiver 8.
The refrigerant enters the cooler 1G via the intercooler 3, and the refrigerant from the cooler 10 passes through the return pipe 17, the switching solenoid valve 5F, and the branch return pipe 17.
It passes through F and is sucked into the two-stage compression refrigerator IF.

(2) When used as C3 class refrigeration equipment.

The refrigerator uses a single-stage compression refrigerator IC, with on-off valves 5F and 3.
F is closed, 5C and 30 are open, and the solenoid valve 12 for the intercooler is closed.

As a result, the refrigerant gas from the single-stage compression refrigerator IC passes through the oil separator 2G, the condensation φ receiver 8, and the intercooler 8, and then enters the cooler 10, and the refrigerant from the cooler passes through the return pipe 171 branch. It is sucked into the single-stage compression refrigerator IC through the pipe 17C.

Here, the switching between Class 1 refrigeration equipment and Class C refrigeration equipment is performed by searching for the optimum state using the microcomputer and controller 14. The microcomputer and controller 14 compare the refrigerating capacity of the refrigerating machine with the current electric power, and switch each on-off valve to maintain a more efficient operating state.

[Effects of the present invention]

As described above, according to the present invention, there are two types of compression: single-stage compression and two-stage compression.
Having different types of refrigerators in the same unit has the following advantages.

(1) Compared to conventional F-class and 03-class dual-purpose units, the device is simpler and has fewer failures.

(2) F-class refrigerators and C=class refrigerators will be installed, and the number of refrigerators will be doubled, but the equipment will be simpler and production costs will be lower.

(3) Since the optimum operating conditions can be obtained depending on the temperature range, the 2M transfer cost is significantly reduced compared to the conventional FIIkC class 3 dual-purpose unit.

(4) The service life of the refrigerator is extended because the refrigerator is not operated under severe conditions.

(5) Since the compressors for class F and class 03 each operate independently, the refrigerators can complement each other in case of emergency.

(6) Installation space can be significantly smaller than in the case of individual units.

[Brief explanation of the drawing]

The figure shows an embodiment of the F-class and C-class frozen and refrigerated two NEETs according to the present invention. In the diagram, 1F--2 stage compression refrigerator IC fist 1#A stage compression refrigerator 2F, 2G--φ oil separator 30, 3F...Switching on-off valve 4F, 4C, fist, check valve 505F...Switching Opening/closing valve 8...Condenser and liquid receiver 7A, 7B...Discharge pipe 3...
...Intercooler i3A...Cooling coil 10...
- Cooler 11... Intermediate withdrawal pipe 11A... Return pipe 12... Solenoid valve 13-1 expansion valve

Claims (1)

[Claims] Each discharge side of the single-stage compression refrigerator and multi-stage compression refrigerator is connected to the condenser through a discharge pipe with a switching valve, and the liquid side of the condenser is connected to the input of the intercooler through a liquid feed pipe. The outlet of the intercooler is connected to the inlet of the cooler by a liquid sending pipe with an expansion valve, and the outlet of the cooler is connected to a return pipe, which branches off from the return pipe, and each branch return pipe has a switching on/off valve. The single-stage compression refrigerator and the multi-stage compression refrigerator are connected to each suction side of the refrigerator, and the single-stage compression refrigerator or the multi-stage compression refrigerator is operated alternately by switching the opening and closing of each of the switching valves. A refrigeration unit that can be used for both F class and C_3 class refrigeration equipment.