JPH0571830A - Freezing device - Google Patents

Abstract

PURPOSE:To perform defrosting of the propeller fan part of the blower for a vaporizer of a freezing device in a short time without being left non-defrosted. CONSTITUTION:During defrosting operation, inching forward and reverse switching operation of a blower 6 for a vaporizer is performed by an inching forward and reverse switching device 18 to cause a propeller fan 12 to generate mechanical vibration. The vibration is exerted on frost started to melt by means of a heater to drop it. Thus, a defrosting time is shortened, and highefficient defrosting operation is effected. Even when temperature in a chamber is reduced, no frost remains on the propeller fan 12 and stable cooling operation is realized without the occurrence of unbalance operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a refrigerating device used in a refrigerator and a refrigerator.

[0002]

2. Description of the Related Art FIG. 3 is a refrigerant circuit diagram of a conventional refrigerating apparatus disclosed in, for example, Japanese Utility Model Laid-Open No. 01-88739, and FIG. 4 is a sectional view showing a state of attachment to a refrigerator which is the refrigerating apparatus of FIG. . In these figures, 1 is a compressor for compressing a refrigerant, 2 is a condenser, 3 is a liquid solenoid valve, 4 is an expansion valve, 5 is an evaporator, and these are sequentially connected by a refrigerant pipe to form a refrigeration cycle. is doing. 6 is a blower for blowing air to the evaporator 5, 7 is a hot gas solenoid valve, which is taken out from the refrigerant pipe between the compressor 1 and the condenser 2, and is in the middle of a bypass pipe 8 connected to the pipe between the expansion valve 4 and the evaporator 5. It is provided in. Reference numeral 9 is a power source for driving the blower 6, 10 is a casing that forms an air path with the drain pan 11 that covers the evaporator 5 and is arranged below the evaporator 5, and is a suspension foot 19 on the ceiling plate 15 in the refrigerator. The blower 6 is fixed and the blower 6 is attached to the air intake side of the casing 10 by the attachment legs 16. Reference numeral 13 is a fan guard arranged in front of the propeller fan 12 of the blower 6, 14 is a heater attached to the fan guard 13, and 17 is an a contact of the electromagnetic contactor for cooling operation.

Next, the operation will be described. During the cooling operation, the compressor 1, the condenser 2, the liquid solenoid valve 3, the expansion valve 4, the evaporator 5
The refrigerant is evaporated by the evaporator 5 of the refrigeration cycle formed by and the blower 6 exchanges heat with the air in the refrigerator to cool the inside of the refrigerator. If the cooling operation continues, frost forms on the evaporator 5, the propeller fan 12 of the blower 6, the fan guard 13 and the like, and the cooling operation begins to be hindered. Therefore, a defrosting timer (not shown) after a predetermined time of the cooling operation
Defrosting operation is started by the defrosting start signal from the etc. In the defrosting operation, the liquid solenoid valve 3 is closed, the hot gas solenoid valve 7 is opened, the refrigerant discharged from the compressor 1 is sent into the evaporator 5, and the frost adhering to the evaporator 5 is melted. On the other hand, the heater 14 is energized, and the frost attached to the fan guard 13 by heat conduction is melted by the radiant heat to the frost attached to the propeller fan 12 of the blower 6, and a defrost detector (not shown) such as a thermostat is used. The defrosting operation is terminated by the defrosting completion signal of and the operation is switched to the cooling operation again.

[0004]

In the conventional refrigeration system, the propeller fan 12 of the blower 6 is heated only by the radiant heat of the heater 14 fixed to the fan guard 13 so as to defrost the frost attached to the propeller fan 12. Therefore, the time required for defrosting the propeller fan 12 becomes long, the defrosting efficiency is poor, and when the temperature inside the refrigerator becomes low, the propeller fan 12 has residual frost and is uncooled during cooling operation. The balance operation is performed, and the propeller fan 12 and the mounting feet 16 of the blower 6 are destroyed, so that there is a problem that stable cooling operation cannot be performed.

The present invention has been made in order to solve the above-mentioned problems, and has a good defrosting efficiency and a defrosting of a propeller fan can be surely performed in a short time even in a usage method in which the temperature inside the refrigerator is low. The purpose is to obtain a refrigeration system that can be used for.

[0006]

A refrigerating apparatus according to the present invention heats a blower that blows air to an evaporator during defrosting, and performs forward / reverse switching operation of the blower every short time. A device is provided. In addition, an inching intermittent operation device for intermittently rotating and driving at short time intervals is provided.

[0007]

In the refrigerating apparatus of the present invention, when the propeller fan of the blower is defrosted, the blower vibrates and adheres to the propeller fan due to the melting by heating and the forward / reverse switching operation of the blower at short time intervals or intermittent operation. The frost is shaken off and defrosting is completed in a short time.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A refrigeration system according to an embodiment of the present invention shown in FIGS. 1 and 2 will be described below. 1 is a refrigerant circuit diagram thereof, and FIG. 2 is an electric circuit diagram of the inching forward / reverse rotation switching operation device of FIG. In these figures, the same reference numerals as those in FIGS. 3 and 4 indicate corresponding parts, and therefore their explanations are omitted. Reference numeral 18 designates an inching forward / reverse rotation switching device connected in parallel with a contact 17 of the electromagnetic contactor for cooling operation, and FIG. 2 is a detailed electric circuit diagram thereof. 19
a is an A contact of a defrost start timer (not shown) that is closed after a predetermined time (for example, 30 minutes) from the start of defrost, 20a is an A contact of the electromagnetic contactor 20 for defrost inching operation, and 21a is a blower. 6 is the A contact of the reversing electromagnetic contactor 21. From this A contact 21a, the primary side is R
Phase → R phase, S phase → S phase, T phase → T phase, secondary side is U phase → V
The wirings are connected so that the phases are V phase → U phase and W phase → W phase. 22a and 22b are A contact and B contact of inching operation timer 22, 23a and 23b are A contact and B contact of reverse rotation timer 23, and 24b is a defrost detector such as a thermostat that detects the end of defrost (Fig. B contact (not shown), 30, 31
Is a wiring extracted from the R phase and S phase as a control power source, and wiring 30 is a defrosting inching operation electromagnetic contactor 20 and a reverse rotation electromagnetic contactor via a B contact 24b of a defrosting detector (not shown). 21, the inching operation timer 22 and the reverse rotation operation timer 23 are connected to the A contacts of inching start timers (not shown) connected by wires 32 and 33. The wiring 31 connected to the S phase is the inching operation timer 22.
Are connected to the A and B contacts 22a and 22b and the A and B contacts 23a and 23b of the reverse operation timer 23. Further, the B contact 22b of the inching operation timer 22 is connected to the electromagnetic contactor 20 for defrosting inching operation by the wiring 36, the reversing operation timer 23 is connected to the A contact 22a by the wiring 37, and the B contact of the reversing operation timer 23 is performed. Contact 23b
An inching operation timer 22 is connected to the A contact 23a by a wiring 34, and a reversing electromagnetic contactor 21 is connected to the A contact 23a.

Next, the operation will be described. Since the cooling operation is the same as the conventional one described above, the description thereof will be omitted. When the cooling operation is performed for a predetermined time and the frost is formed on the propeller fan 12 of the evaporator 5 and the blower 6 and the fan guard 13 arranged in front of the propeller fan 12 as shown in FIG.
The liquid solenoid valve 3 is closed and the hot gas solenoid valve 7 is opened by a defrost start signal from a defrost start timer (not shown) or the like, and the compressor 1 supplies high-temperature and high-pressure gas refrigerant to the evaporator 5. At the same time, the heater 14 attached to the fan guard 13 of the blower 6 as shown in FIG. 4 and the inching start timer (not shown) are energized to start the defrosting operation. A predetermined time (for example, 30 minutes) after the start of the defrosting operation, the A contact 19a of the inching start timer is closed. At this time, inching operation timer 22
Since the B contact 22b and the B contact 23b of the reverse rotation timer 23 are closed, the inching operation timer 22 and the defrosting operation magnetic contactor 20 connected to the B contacts 22b and 23b are connected.
Is energized, the A contact 20a of the electromagnetic contactor 20 for defrosting operation is closed, the positive phase voltage is supplied to the blower 6, and the blower 6 starts normal rotation operation. On the other hand, the inching operation timer 22 is energized and then timed up after a predetermined time (for example, 1 second) to open its B contact 22b and close its A contact 22a. As a result, the electromagnetic contactor 20 for defrosting operation is cut off, the electromagnetic contactor 20 for defrosting operation is de-energized, and its A contact 20a is opened, so that the normal phase to the blower 6 The power supply is cut off, but at the same time energization of the reverse rotation operation timer 23 is started, so that the momentary A contact 23a is closed,
The electromagnetic contactor 21 for reverse rotation is energized, and its A contact 21a is closed. Then, the reverse phase power is supplied to the blower 6, and the blower 6 starts reverse rotation operation. Further, in the reverse rotation operation timer 23, the A contact 23a is opened and the B contact 23b is closed after a predetermined time (for example, 1 second) after the energization. As a result, the contactor 21 for defrosting inching operation is energized, the energization to the electromagnetic contactor 21 for reverse operation is cut off, the original positive-phase power is supplied to the blower 6, and the blower 6 starts normal rotation operation. The above operation is repeated until the B contact of the defrosting detector (not shown) is opened, and during that time, the blower 6 is moved in the correct direction.
The vibration of the propeller fan 12 due to the reverse rotation operation is applied to the frost that adheres to the propeller fan 12 and begins to melt due to the heat of the heater 14 during the defrosting operation, and the vibration causes it to fall and defrosting is performed in a short time. . When the defrosting is completed, the defrosting end signal from the defrosting detector (not shown) terminates the defrosting operation, and the B contact 24b is opened, and the inching forward / reverse switching operation device 1
The power supply to 8 is cut off, and the forward / reverse operation of the blower 6 is also ended. In the above embodiment, the blower 12 is operated for forward / reverse rotation switching operation for each short time at the time of defrosting, but not limited to this, for example, the blower is rotationally driven intermittently at short time intervals. The intermittent operation device (not shown) configured by a timer or the like may be used for intermittent operation, and the same effect can be obtained.

[0010]

As described above, according to the present invention, during the defrosting operation, the fan is heated and the blower is operated in the forward / reverse switching operation or the intermittent intermittent operation, and the vibration generated in the propeller fan by this operation is reduced. The frost that adheres to the propeller fan and begins to melt due to the heat of the heater is given to drop the frost, so defrosting is performed in a short time to improve the defrosting efficiency, and unbalanced operation due to residual frost Is eliminated, and stable refrigeration operation becomes possible.

[Brief description of drawings]

FIG. 1 is a refrigerant circuit diagram of a refrigerating apparatus according to an embodiment of the present invention.

FIG. 2 is an electric circuit diagram of the inching forward / reverse rotation switching operation device shown in FIG.

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

FIG. 4 is a cross-sectional view showing how a conventional refrigeration system is attached to a refrigerator.

[Explanation of symbols]

 1 Compressor 2 Condenser 4 Expansion valve 5 Evaporator 6 Blower 14 Heater 18 Inching forward / reverse switching operation device

Claims (2)

[Claims] 1. A defroster is provided by heating with a heater frost attached to the blower of a refrigeration cycle in which a compressor, a condenser, an expansion valve, and an evaporator equipped with a blower are connected in a closed loop. The refrigerating apparatus according to claim 1, further comprising an inching forward / reverse rotation switching operation device that performs a forward / reverse rotation switching operation of the blower at short time intervals during the defrosting. 2. A defroster is provided by heating with a heater frost attached to the blower of a refrigeration cycle in which a compressor, a condenser, an expansion valve, and an evaporator having a blower are connected in a closed loop. The refrigerating apparatus according to claim 1, further comprising an inching intermittent operation device that intermittently rotates the blower at short time intervals during the defrosting.