JPH0542974U - Refrigeration equipment - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the temperature inside the freezer 7 from rising abnormally due to a failure of the flow rate control valve 9 or the like. [Composition] After the start of the full capacity operation, when the temperature inside the freezer 7 rises above a predetermined temperature, the compressor 1 is stopped.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a refrigerating apparatus suitable for cooling the inside of a freezer.

[0002]

[Prior Art]

 An example of a conventional refrigeration system is shown in FIG. During the operation of the refrigeration system, the refrigerant gas discharged from the compressor 1 enters the condenser 2 as shown by the solid arrow and is condensed and liquefied by exchanging heat with the outside air sent from the fan 3 there. This refrigerant liquid enters the throttling mechanism 4 such as an expansion valve, is depressurized by being throttled there, and then enters the evaporator 5, where the air inside the freezer 7 sent from the fan 6 is cooled. Evaporate and vaporize. Then, this refrigerant gas is sucked into the compressor 1 and compressed again.

A flow rate control valve 9 is provided in a bypass passage 8 connected in parallel to the condenser 2 and the throttle mechanism 4, and the opening degree of the flow rate control valve 9 is detected by a temperature sensor 10. PID control is performed according to the deviation between the internal temperature and the set temperature. Thus, a part of the refrigerant gas discharged from the compressor 1 is guided to the evaporator 5 through the bypass passage 8 as indicated by the broken line arrow, and the freezer is controlled by controlling the flow rate by the flow rate control valve 9. The inside temperature of 7 is maintained at the set temperature.

[0004]

[Problems to be solved by the device]

 In the above conventional refrigeration system, the flow control valve 9 is fully closed and fully operated from the start of its operation until the temperature inside the freezer 7 is cooled to the set temperature. If 9 remains open due to its failure, etc., the high temperature refrigerant gas flows into the evaporator 5 via the bypass passage 8 and the temperature inside the freezer 7 rises abnormally. As a result, inside the freezer 7 There was a problem that it had a bad effect on the internal components housed in.

Particularly, when an electronic expansion valve is used as the throttle mechanism 4, the opening of this electronic expansion valve advances in the closing direction so that the low pressure on the suction side of the compressor 1 does not exceed a predetermined value. Since the flow rate of the refrigerant gas passing through the bypass passage 8 increases, the damage to the built-in objects becomes great.

[0006]

[Means for Solving the Problems]

 The present invention has been proposed to solve the above problems, and the gist of the present invention is to connect a compressor, a condenser, a throttle mechanism, and an evaporator in this order to the condenser and the throttle mechanism. In the refrigeration system that maintains the temperature of the cooled object cooled by the evaporator at the set temperature by controlling the flow rate of the refrigerant passing through the bypass passages connected in parallel with each other, A refrigerating apparatus is provided with means for stopping the compressor when the temperature rises above a predetermined temperature.

[0007]

[Action]

 Since the present invention has the above-mentioned configuration, the compressor is stopped when the temperature of the object to be cooled rises above the predetermined temperature after the full capacity operation of the refrigeration system is started.

[0008]

【Example】

 One embodiment of the present invention is shown in FIGS. The signal from the operation switch 11 and the signal from the temperature sensor 10 for detecting the temperature inside the freezer 7 are input to the controller 20, which is based on the control flow shown in FIG. 2 and the compressor 1, the flow control valve 9, and the fan. It outputs to 3 and 6. Other configurations are similar to those of the conventional one shown in FIG. 3, and corresponding members are designated by the same reference numerals.

Then, as shown in FIG. 2, when the operation switch 11 is turned on in step 1, it is confirmed whether or not the internal cold storage temperature detected by the temperature sensor 10 in step 2 is higher than the set temperature. If not, the fan 6 is operated in step 3. In that case, the compressor 1 is operated in step 4, the fans 3 and 6 are operated in step 5, and the flow rate control valve 9 is fully closed in step 6, so that the refrigeration system operates at full capacity. Start.

Next, in step 7, it is determined whether the internal cold storage temperature has dropped or increased, and if it has decreased, then in step 8 it is confirmed whether the internal cold storage temperature has dropped to the set temperature. If not, the process returns to step 4, but in that case, the opening of the flow control valve 9 is adjusted by PID control in step 9 to evaporate by adjusting the amount of refrigerant passing through the bypass passage 8. The cooling capacity of the container 5 is adjusted to maintain the internal temperature at the set temperature. If it is determined in step 7 that the internal temperature has risen, that is, if the flow rate control valve 9 is still open due to a failure or the like, in step 10 it is confirmed whether the internal temperature has risen to the predetermined temperature. If not, the process returns to step 4, but in that case, the compressor 1 is stopped in step 11, the fans 3 and 6 are stopped in step 12, and an alarm is issued in step 13.

Note that the predetermined temperature is preferably slightly higher than the outside air temperature in order to clearly distinguish it from the rise in the inside temperature due to the opening of the door of the freezer 7. Of course, the present invention can be widely applied not only to cooling the air in the freezer 7 but also to a refrigerating device for cooling any object to be cooled.

[0012]

[Effect of the device]

 In the present invention, since the compressor is stopped when the temperature of the object to be cooled rises above the predetermined temperature after the start of the full capacity operation, it is possible to prevent the abnormal increase in the temperature of the object to be cooled due to the failure of the flow control valve. .

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of the present invention.

FIG. 2 is a control flowchart of the above embodiment.

FIG. 3 is a system diagram of a conventional refrigeration system.

[Explanation of symbols]

 1 Compressor 2 Condenser 4 Throttling mechanism 5 Evaporator 7 Freezer 8 Bypass path 9 Flow rate control valve 10 Temperature sensor 11 Operation switch 20 Controller

Claims (1)

[Scope of utility model registration request] 1. The evaporation is performed by connecting a compressor, a condenser, a throttle mechanism and an evaporator in this order, and controlling a flow rate of a refrigerant through a bypass passage connected in parallel to the condenser and the throttle mechanism. In the refrigerating apparatus for maintaining the temperature of the cooled object to be set at the set temperature by means of the cooling device, a means for stopping the compressor is provided when the temperature of the cooled object rises above a predetermined temperature after the start of full capacity operation. A refrigerating device characterized by the above.