JPH10153378A - Defrosting control device of refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the temperature inside a compartment adjusting the number of wires for defroster heater and exciting time. SOLUTION: The temperature rise inside a compartment is prevented and the temperature inside the compartment is stabilized by exciting either of a first defroster 23 or a second defroster 24 that is more frosted when the detected temperatures by a first evaporator temperature detecting means 13 and a second evaporator temperature detecting means 14 are lower than the predetermined temperature set by the starting temperature of exciting heater setting means 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defrost control device for a cooling device of a commercial refrigerator, a showcase, a vending machine and the like.

[0002]

2. Description of the Related Art In recent years, a defrosting control device for a cooling device of a commercial refrigerator, a showcase, a vending machine, etc. has been disclosed in Japanese Patent Application Laid-Open No. Sho 62-2.
There is one disclosed in Japanese Patent No. 25879.

An example of a conventional defrosting control device for a cooling device such as a commercial refrigerator, a showcase, and a vending machine will be described below with reference to the drawings.

FIG. 12 is a block diagram of a conventional defrosting control device for a cooling device. In FIG. 12, reference numeral 1 denotes a temperature sensor as a means for detecting the temperature in the refrigerator, 2 denotes a door switch for detecting the open / closed state of the door, 3 denotes a microcomputer for performing defrost control,
5 is a relay switch, 6 is a compressor, 7 is a heater for defrosting,
8 is a power supply.

[0005]

However, in the above-mentioned conventional configuration, since only one heater 7 is used for defrosting, electricity is supplied also to a portion of the evaporator where there is little frost, and the inside of the chamber is increased due to the large number of locations where electricity is supplied to the heater. There is a drawback that the temperature rises and the power consumption increases.

SUMMARY OF THE INVENTION The present invention solves the conventional problems, and a defrost heater of a cooling device which can prevent a rise in temperature in a refrigerator and save power by energizing a defrost heater only in a portion of the evaporator where frost is large. It is an object to provide a control device.

[0007]

According to the present invention, there is provided a defrosting control apparatus for a cooling apparatus, comprising: an evaporator; a plurality of defrost heaters disposed in the evaporator; Evaporator temperature detecting means such as a plurality of thermistors for detecting the temperature of the evaporator, a timer defrost start time setting means, a timer, a heater energization start temperature setting means, the timer defrost start time setting means, A storage unit for storing a heater energization start temperature setting unit, and when the time of the timer connected to the storage unit reaches a time set by the timer defrost start time setting unit, the temperature is detected by the evaporator temperature detection unit. An arithmetic unit for determining whether or not the temperature is equal to or lower than the temperature set by the heater energization start temperature setting means; When the temperature detected by the evaporator temperature detecting means is a temperature below that set by the heater energization start temperature setting means, and a control unit issues an instruction signal for energizing only that the defrost heater.

[0008] Thus, by energizing the defrost heater only to a portion of the plurality of defrost heaters where there is a lot of frost on the evaporator, it is possible to prevent a rise in the temperature in the refrigerator and to save power.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention detects the temperature of an evaporator, a plurality of defrost heaters disposed in the evaporator, and the evaporator around each of the defrost heaters. A plurality of evaporator temperature detecting means such as thermistors, a timer defrost start time setting means, a timer, a heater energization start temperature setting means, the timer defrost start time setting means, and the heater energization start temperature setting means are stored. When the time of the timer connected to the storage unit reaches the time set by the timer defrost start time setting unit, the temperature detected by the evaporator temperature detection unit is set to the heater energization start temperature setting. A calculating unit for determining whether the temperature is equal to or lower than a temperature set by the means, and a temperature connected to the calculating unit and detected by the evaporator temperature detecting means. When the temperature is equal to or lower than the temperature set by the heater energization start temperature setting means, the evaporator is configured to output an energization instruction signal only to the defrost heater. When the defrost heater is energized only at a location where there is a lot of frost, the inside temperature can be prevented from rising.

According to a second aspect of the present invention, it is determined whether or not the temperature detected by the evaporator temperature detecting means is equal to or lower than the temperature set by the heater energization start temperature setting means. A calculating unit for comparing the detected temperatures with each other; and when the temperature detected by the evaporator temperature detecting unit is equal to or lower than the temperature set by the heater energization starting temperature setting unit, the evaporator temperature detecting unit is connected to the calculating unit. And a control unit that issues an energization instruction signal in order from the lower temperature of the defrost heater among the temperatures detected in the above, from among the frosted portions of the evaporator among a plurality of the defrost heaters By sequentially energizing the defrost heater, it has the effect of preventing a rise in the internal temperature and saving power.

According to a third aspect of the present invention, there is provided a heater energization end temperature setting means for setting a temperature at which energization of the defrost heater is ended in advance for each temperature detected by the evaporator temperature detection means, and the evaporator temperature detection means. It is determined whether the temperature detected by the means is equal to or lower than the temperature set by the heater energization start temperature setting means, and when the heater is energized, the temperature detected by the evaporator temperature detection means is set by the heater energization end temperature setting means. A calculating unit for determining whether the temperature is equal to or lower than the set temperature, and the defrost heater connected to the calculating unit until the temperature detected by the evaporator temperature detecting means reaches a temperature equal to or higher than a temperature set by the heater energizing end temperature setting means. And a control unit for issuing an energizing instruction signal to the evaporator temperature detecting means for detecting the energizing time of the defrost heater by the evaporator temperature detecting means. Suitable and time, has the effect of preventing temperature rise in the evaporator of the frost with a lot locations to efficiently Defrost box.

According to a fourth aspect of the present invention, there is provided an outside air temperature detecting means such as a thermistor for detecting the outside air temperature around the main body, and a temperature at which the energization of the defrost heater is terminated in advance for each temperature detected by the outside air temperature detecting means. Determining whether the temperature detected by the heater energization end temperature setting means is equal to or lower than the temperature set by the heater energization start temperature setting means. A calculating unit for determining whether the temperature detected by the detecting unit is equal to or lower than the temperature set by the heater energizing end temperature setting unit; and a heater connected to the calculating unit and detecting the temperature detected by the evaporator temperature detecting unit. A controller for issuing an energization instruction signal to the defrost heater until the temperature reaches or exceeds a temperature set by the energization end temperature setting means. Has the effect of preventing the temperature rise inside and cabinet effective Defrost changed according energization time over data on the outside air temperature detected by said outside air temperature detecting means.

According to a fifth aspect of the present invention, there is provided an operation rate detecting means for detecting an operation rate of the compressor, and a temperature at which energization of the defrost heater is terminated in advance for each operation rate detected by the operation rate detection means. It is determined whether the temperature detected by the heater energization end temperature setting means to be set and the temperature detected by the evaporator temperature detection means is equal to or lower than the temperature set by the heater energization start temperature setting means. A calculating unit for determining whether the temperature detected by the means is equal to or lower than the temperature set by the heater energizing end temperature setting means, and a temperature detected by the evaporator temperature detecting means connected to the calculating unit. And a controller for issuing an energization instruction signal to the defrost heater until the temperature reaches or exceeds the temperature set by the end temperature setting means. Has the effect of preventing the temperature rise inside and cabinet effective Defrost changed according to time to the operation rate of the compressor detected by the operation ratio detecting means.

(Embodiment 1) FIG. 1 is a block diagram of a defrosting control device for a cooling device according to Embodiment 1 of the present invention. FIG. 2 is a refrigeration cycle diagram of the defrost control device for the cooling device according to the first embodiment of the present invention. FIG. 3 is a flowchart of the defrost control device for the cooling device according to the first embodiment of the present invention.

1 and 2, reference numeral 9 denotes a timer, 10
Is a timer defrost start time setting means for setting defrosting to be started on time; 11 is a heater energization start temperature setting means for setting a temperature at which energization of a defrosting heater is started; and 12 is a storage unit. The time set by the start time setting means 10 and the temperature set by the heater energization start temperature setting means 11 are stored. 13 is a first evaporator temperature detecting means such as a thermistor for detecting the temperature of the evaporator around the first defrost heater 23, and 14 is a thermistor for detecting the temperature of the evaporator around the second defrost heater 24, etc. Second evaporator temperature detecting means, 15
Are the timer 9, the storage unit 12, the first evaporator temperature detecting means 13, and the second evaporator temperature detecting means 14.
And 16 is a control means for controlling the first relay 17, the second relay 18, and the third relay 19 based on the signal from the arithmetic unit 15. Reference numeral 20 denotes a contact of the first relay 17, and the compressor 6 is connected between power supply lines. Reference numeral 21 denotes a contact of the second relay 18 and a first defrost heater 22 between the power supply lines.
3 are connected. Reference numeral 22 denotes a contact of the third relay 19, and a second defrost heater 24 between the power supply lines.
Is connected.

Reference numeral 25 denotes the timer 9, the storage unit 12,
This is a control box including the first evaporator temperature detecting means 13, the second evaporator temperature detecting means 14, the arithmetic unit 15, and the control unit 16.

The operation of the defrosting control device for a cooling device configured as described above will be described with reference to FIG.

In STEP 1, the defrosting start time is set to A by the timer defrost start time setting means 10;
The heater energization start temperature setting means 11 sets a temperature B at which energization of the defrost heater is started.

At STEP 2, when the time T of the timer 9 reaches the defrosting start time A, at STEP 3, the first relay 17 is excited to open the first contact 20, and the operation of the compressor 3 is stopped. I do.

In step 4, when the temperature b1 detected by the first evaporator temperature detecting means 13 is lower than the heater energization start temperature B, the second relay 18 is excited in step 6 to close the second contact point 21, The first defrost heater 2
The energization of No. 3 is started.

In step 5, when the temperature b2 detected by the second evaporator temperature detecting means 14 is lower than the heater energization start temperature B, the third relay 19 is excited in step 6 to close the third contact point 22, The second defrost heater 2
The energization of No. 4 is started.

As described above, the defrosting control device of the cooling device according to the present embodiment includes the evaporator 26, the first defrost heater 23, the second defrost heater 24 disposed in the evaporator 26, and the evaporator 26. A first defrost heater 23,
The first evaporator temperature detecting means 13 for detecting the temperature of the evaporator around each of the second defrost heaters 24;
The second evaporator temperature detecting means 14, the timer defrost start time setting means 10, the timer 9,
The heater energization start temperature setting unit 11, the timer defrost start time setting unit 10, a storage unit 12 for storing the heater energization start temperature setting unit 11, and the time of the timer 9 connected to the storage unit 12 is set to At the time when the time set by the timer defrost start time setting means 10 is reached, the temperatures detected by the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means 14 become the heater energization starting temperature setting means. A calculating unit 15 for determining whether the temperature is equal to or lower than the temperature set in 11; and a detecting unit connected to the calculating unit 15 for detecting the temperature by the first evaporator temperature detecting unit 13 and the second evaporator temperature detecting unit 14. When the temperature is equal to or lower than the temperature set by the heater energization start temperature setting means 11,
The first defrost heater 23 and the second defrost heater 24 have much frost on the evaporator 26. The control unit 16 outputs an energization instruction signal only to the defrost heater. By energizing only the location, it is possible to prevent the temperature inside the refrigerator from rising.

In this embodiment, two defrost heaters and two evaporator temperature detecting means for detecting the temperature of the evaporator around each of the defrost heaters are used. Means 3 each
There may be more than one book. When a plurality of defrost heaters and evaporator temperature detecting means are provided, an effect is obtained in which defrosting of the evaporator 3 is performed finely according to a frosted portion.

(Embodiment 2) FIG. 4 is a block diagram of a defrost control device for a cooling device according to Embodiment 2 of the present invention. FIG. 5 is a flowchart of a defrosting control device for a cooling device according to Embodiment 2 of the present invention.

In FIG. 4, reference numeral 15a denotes an arithmetic unit, and the temperatures detected by the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means 14 are set by the heater energization starting temperature setting means 11. It is determined whether the temperature is equal to or lower than the temperature, and the temperature detected by the first evaporator temperature detecting means 13 and the temperature detected by the second evaporator temperature detecting means 14 are compared. 16a is a defrost heater which receives a signal from the control unit 15a and detects a temperature detected by the first evaporator temperature detecting means 13 from a lower temperature among the temperatures detected by the second evaporator temperature detecting means 14. To start energizing.

The operation of the defrosting control device for a cooling device configured as described above will be described with reference to FIG.

In STEP1, the defrosting start time is set to A by the timer defrost start time setting means 10;
The temperature B at which the energization of the heater for defrosting is started by the energization start temperature setting means 11 for the heater.

In STEP 2, when the time T of the timer 9 reaches the defrosting start time A, in STEP 3, the first relay 17 is excited to open the first contact 20, and the operation of the compressor 3 is stopped. I do.

In STEP4, when the temperature b1 detected by the first evaporator temperature detecting means 13 is lower than the heater energization start temperature B, in STEP6, energization of the lower defrost heater of b1 and b2 is started.

In STEP5, when the temperature b2 detected by the second evaporator temperature detecting means 14 is lower than the heater energization start temperature B, in STEP6, energization of the lower defrost heater of b1 and b2 is started.

When the energization of the lower defrost heater of b1 and b2 is terminated in STEP7, the energization of the higher defrost heater of b1 and b2 is started in STEP8.

As described above, in the defrosting control device of the cooling device according to the present embodiment, the temperature detected by the first evaporator temperature detecting means 13 and the second It is determined whether the temperature is equal to or lower than the temperature set by the starting temperature setting means 11 and the temperature detected by the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means 1 are determined.
An arithmetic unit 15a for comparing the temperatures detected in step 4 with the temperature detected by the first evaporator temperature detecting means 13 and the temperature detected by the second evaporator temperature detecting means 14 upon receiving a signal from 15a; And the controller 16a which starts the energization of the defrost heater from a lower temperature, so that the energization of the defrost heaters is performed one by one in order, thereby preventing the temperature inside the refrigerator from rising.

In this embodiment, two defrost heaters and two evaporator temperature detecting means for detecting the temperature of the evaporator around each of the defrost heaters are used. Means 3 each
There may be more than one book. When a plurality of defrost heaters and evaporator temperature detecting means are provided, and the number of heaters to be energized is limited to a few lower ones, an effect of power saving can be obtained.

(Embodiment 3) FIG. 6 is a block diagram of a defrosting control device for a cooling device according to Embodiment 3 of the present invention. FIG. 7 is a blow chart of the defrost control device for the cooling device according to the third embodiment of the present invention.

In FIG. 6, reference numeral 27 denotes a heater energization end temperature setting means for setting a temperature at which energization of the defrosting heater is ended, and 15b an arithmetic unit which comprises the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means. It is determined whether or not the temperature detected by the evaporator temperature detecting means 14 is equal to or lower than the temperature set by the heater energizing start temperature setting means 11, and when the heater is energized, the temperature detected by the first evaporator temperature detecting means 13 is determined. And whether the temperature detected by the second evaporator temperature detecting means 14 is equal to or higher than the temperature set by the heater energizing end temperature setting means 27. A controller 16b receives a signal from the controller 15b and the temperature detected by the first evaporator temperature detector 13 and the second evaporator temperature detector 14 is equal to or lower than the temperature set by the heater energization start temperature setting unit. At this time, an energization instruction signal is output only to the defrost heater, and when the temperature reaches or exceeds the temperature set by the heater energization end temperature setting means 27, the energization of the defrost heater is ended.

The operation of the defrosting control device for a cooling device configured as described above will be described with reference to FIG.

In STEP 1, the timer defrost start time setting means 10 sets the defrosting start time to A,
The heater energization start temperature setting means 11 sets the temperature B at which energization of the defrost heater starts, and the heater energization end temperature setting means 27 sets the temperature of the defrost heater for each temperature detected by the evaporator temperature detection means. The temperature C at which the energization ends is set.

In STEP 2, when the time T of the timer 9 reaches the defrosting start time A, in STEP 3, the first relay 17 is excited to open the first contact 20, and the operation of the compressor 3 is stopped. I do.

In step 4, when the temperature b1 detected by the first evaporator temperature detecting means 13 is lower than the heater energization start temperature B, the second relay 18 is excited in step 6 to close the second contact point 21, The first defrost heater 2
The energization of No. 3 is started.

In STEP 5, when the temperature b2 detected by the second evaporator temperature detecting means 14 is lower than the heater energization start temperature B, the third relay is excited in STEP 6 to close the third contact 22, and The energization of the second defrost heater 24 is started.

In STEP 7, when the temperature b1 detected by the first evaporator temperature detecting means 13 is lower than the heater energization end temperature C, the second relay 18 is excited in STEP 9 to open the second contact point 21, The first defrost heater 2
The energization of 3 is ended.

In STEP 8, when the temperature b2 detected by the second evaporator temperature detecting means 14 is equal to or lower than the heater end temperature C, the third relay 19 is excited in STEP 9 to open the third contact 22, The second defrost heater 2
The energization of No. 4 is completed.

As described above, in the defrosting control device of the cooling device according to the present embodiment, the temperature detected by the first evaporator temperature detecting means 13 and the second It is determined whether or not the temperature is equal to or lower than the temperature set by the start temperature setting means 11, and when the heater is energized, the temperature detected by the first evaporator temperature detecting means 13 and the temperature detected by the second evaporator temperature detecting means 14 are detected. A computing unit 15a for determining whether or not the temperature is equal to or higher than a temperature set by the heater energization termination temperature setting unit 27; a first evaporator temperature detecting unit 13 receiving the signal from the 15a; and a second evaporator temperature When the temperature detected by the detection means 14 is equal to or lower than the temperature set by the heater energization start temperature setting means, an energization instruction signal is issued only to the defrost heater, and the heater energization end temperature setting means 27 When the temperature reaches a predetermined temperature or higher, the control unit 16a terminates the energization of the defrost heater. Therefore, the energization time of the defrost heater is changed according to the frosted state of the evaporator 26 to effectively defrost. Thus, the temperature inside the refrigerator can be prevented from rising.

In this embodiment, two defrost heaters and two evaporator temperature detecting means for detecting the temperature of the evaporator around each of the defrost heaters are used. Means 3 each
There may be more than one book. When a plurality of defrost heaters and evaporator temperature detecting means are provided, an effect is obtained in which defrosting of the evaporator 3 is performed finely according to a frosted portion.

(Embodiment 4) FIG. 8 is a block diagram of a defrosting control device for a cooling device according to Embodiment 4 of the present invention. FIG. 9 is a flowchart of a defrost control device for a cooling device according to Embodiment 4 of the present invention.

In FIG. 8, reference numeral 28 denotes an outside air temperature detecting means for detecting the outside air temperature around the main body, 27a a heater energizing end temperature setting means for setting a temperature at which energization of the defrosting heater ends, and 15c an arithmetic unit. It is determined whether or not the temperatures detected by the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means 14 are lower than the temperature set by the heater energization start temperature setting means 11, and the time when the heater is energized is determined. It is determined whether the temperature detected by the first evaporator temperature detecting means 13 is equal to or higher than the temperature detected by the second evaporator temperature detecting means 14 by the heater energizing end temperature setting means 27a. . A controller 16c receives a signal from the controller 15c, and the temperature detected by the first evaporator temperature detector 13 and the second evaporator temperature detector 14 is equal to or lower than the temperature set by the heater energization start temperature setting unit. At this time, an energization instruction signal is output only to the defrost heater, and when the temperature reaches or exceeds the temperature set by the heater energization end temperature setting means 27a, the energization of the defrost heater is ended.

The operation of the defrosting control device for a cooling device configured as described above will be described with reference to FIG.

In STEP 1, the outside air temperature is detected by the outside air temperature detecting means 28. In STEP2, the defrosting start time setting means 10 sets the defrosting start time to A, the heater energization start temperature setting means 11 sets the temperature B at which energization of the defrosting heater is started, and the outside air temperature detecting means 28. The temperature D at which the energization of the heater for defrosting is ended is set by the heater energization end temperature setting means 27a for each temperature detected in step (1).

In STEP 3, when the time T of the timer 9 reaches the defrosting start time A, in STEP 4, the first relay 17 is excited to open the first contact 20, and the operation of the compressor 3 is stopped. I do.

In step 5, when the temperature b1 detected by the first evaporator temperature detecting means 13 is lower than the heater energization start temperature B, the second relay 18 is excited in step 7 to close the second contact point 21, The first defrost heater 2
The energization of No. 3 is started.

In step 6, when the temperature b2 detected by the second evaporator temperature detecting means 14 is lower than the heater energization start temperature B, the third relay 19 is excited in step 7 to close the third contact 22, The second defrost heater 2
The energization of No. 4 is started.

In STEP 8, when the temperature b1 detected by the first evaporator temperature detecting means 13 is lower than the heater energizing end temperature D, the second relay 18 is excited in STEP 10 to open the second contact point 21, The energization of the first defrost heater 23 ends.

In step 9, when the temperature b2 detected by the second evaporator temperature detecting means 14 is lower than the heater end temperature C, the third relay 19 is excited in step 10 to open the third contact point 22, The energization of the second defrost heater 24 ends.

As described above, the defrosting control device of the cooling apparatus according to the present embodiment comprises the outside air temperature detecting means, the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means 14.
The temperature detected in step 11 is the heater energization start temperature setting means 11.
It is determined whether the temperature is equal to or lower than the temperature set in the above. When the heater is energized, the temperature detected by the first evaporator temperature detecting means 13 and the temperature detected by the second evaporator temperature detecting means 14 are terminated. A computing unit 15c for determining whether or not the temperature is equal to or higher than the temperature set by the temperature setting unit 27a; a signal from the computing unit 15c which receives the signal from the computing unit 15c; When the temperature is lower than the temperature set by the heater energization start temperature setting means,
The controller 16a outputs an instruction signal for energizing only the defrost heater, and when the temperature reaches or exceeds the temperature set by the heater energizing end temperature setting means 27a, the controller 16a ends the energization of the defrost heater. By changing the energizing time of the defrost heater in accordance with the outside air temperature, effective defrosting can be performed, and a rise in the temperature inside the refrigerator can be prevented.

In the present embodiment, two defrost heaters and two evaporator temperature detecting means for detecting the temperature of the evaporator around each defrost heater are used. Means 3 each
There may be more than one book. When a plurality of defrost heaters and evaporator temperature detecting means are provided, an effect is obtained in which defrosting of the evaporator 3 is performed finely according to a frosted portion.

(Embodiment 5) FIG. 10 is a block diagram of a defrosting control device for a cooling device according to Embodiment 5 of the present invention. FIG. 11 is a flowchart of a defrost control device for a cooling device according to Embodiment 5 of the present invention.

In FIG. 10, 29 is an operation rate detecting means for detecting the operation rate of the compressor 6, 27b is a heater energization end temperature setting means for setting a temperature at which energization of the heater for defrosting is ended, and 15d is an arithmetic unit. Then, it is determined whether the temperature detected by the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means 14 is lower than the temperature set by the heater energization start temperature setting means 11, At the time of energization, it is determined whether the temperature detected by the first evaporator temperature detecting means 13 and the temperature detected by the second evaporator temperature detecting means 14 are equal to or higher than the temperature set by the heater energizing end temperature setting means 27a. to decide. A controller 16d receives a signal from the controller 15d and the temperature detected by the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means 14 is equal to or lower than the temperature set by the heater energization start temperature setting means. Time,
An energization instruction signal is output only to the defrost heater, and when the temperature reaches or exceeds the temperature set by the heater energization end temperature detecting means 27b, the energization of the defrost heater is ended.

The operation of the defrosting control device for a cooling device configured as described above will be described with reference to FIG.

In STEP 1, the driving rate is detected by the driving rate detecting means 29. In STEP 2, the timer defrost start time setting means 10 sets the defrosting start time to A, the heater energization start temperature setting means 11 sets the temperature B at which energization of the defrosting heater is started, and the operation rate detecting means 29 The temperature E at which the energization of the defrosting heater is ended is set by the heater energization end temperature detecting means 27b for each of the operation rates detected in the step (1).

In STEP 3, when the time T of the timer 9 reaches the defrosting start time A, in STEP 4, the first relay 17 is excited to open the first contact 20, and the operation of the compressor 3 is stopped. I do.

In STEP 5, when the temperature b1 detected by the first evaporator temperature detecting means 13 is lower than the heater energization start temperature B, the second relay 18 is excited to close the second contact 21 in STEP 7, The first defrost heater 2
The energization of No. 3 is started.

In STEP 6, when the temperature b2 detected by the second evaporator temperature detecting means 14 is lower than the heater energization start temperature B, the third relay 19 is excited in STEP 7 to close the third contact 22, The second defrost heater 2
The energization of No. 4 is started.

In STEP 8, when the temperature b1 detected by the first evaporator temperature detecting means 13 is lower than the heater energization end temperature E, the second relay 18 is excited in STEP 10 to open the second contact point 21, The energization of the first defrost heater 23 ends.

In step 9, when the temperature b2 detected by the second evaporator temperature detecting means 14 is lower than the heater end temperature E, the third relay 19 is excited in step 10 to open the third contact 22, The energization of the second defrost heater 24 ends.

As described above, the defrosting control device of the cooling system according to the present embodiment comprises the operation rate detecting means 29, the first evaporator temperature detecting means 13 and the second evaporator temperature detecting means 14. It is determined whether the detected temperature is equal to or lower than the temperature set by the heater energization start temperature setting means 11, and when the heater is energized, the temperature detected by the first evaporator temperature detection means 13 and the second evaporator A computing unit 15d for determining whether the temperature detected by the temperature detecting means 14 is equal to or higher than the temperature set by the heater energizing end temperature setting means 27b;
d from the first evaporator temperature detecting means 13
When the temperature detected by the second evaporator temperature detecting means 14 is equal to or lower than the temperature set by the heater energizing start temperature setting means, an energizing instruction signal is issued only to the defrost heater, and the heater energizing end temperature setting is performed. When the temperature reaches or exceeds the temperature set by the means 27b, the control unit 16d terminates the energization of the defrost heater. Therefore, the energization time of the defrost heater is changed according to the operation rate of the compressor to effectively defrost. Thus, the temperature inside the refrigerator can be prevented from rising.

In this embodiment, two defrost heaters and two evaporator temperature detecting means for detecting the temperature of the evaporator around each of the defrost heaters are used. Means 3 each
There may be more than one book. When a plurality of defrost heaters and evaporator temperature detecting means are provided, an effect is obtained in which defrosting of the evaporator 3 is performed finely according to a frosted portion.

[0067]

As described above, the present invention relates to an evaporator, a plurality of defrost heaters disposed in the evaporator, and a plurality of thermistors for detecting the temperature of the evaporator around each of the defrost heaters. Evaporator temperature detecting means,
Timer defrost start time setting means, a timer,
A heater energization start temperature setting unit, the timer defrost start time setting unit, a storage unit that stores the heater energization start temperature setting unit, and a timer time connected to the storage unit and the timer set by the timer defrost start time setting unit. At the point in time when the set time is reached, an arithmetic unit that determines whether the temperature detected by the evaporator temperature detecting unit is equal to or lower than the temperature set by the heater energization start temperature setting unit, and connected to the arithmetic unit, When the temperature detected by the evaporator temperature detection means is equal to or lower than the temperature set by the heater energization start temperature setting means, the control unit issues an energization instruction signal only to the defrost heater,
By energizing the defrost heater only to the frosted portion of the evaporator among the plurality of defrost heaters, it is possible to prevent the temperature inside the refrigerator from rising.

Also, it is determined whether the temperature detected by the evaporator temperature detecting means is lower than the temperature set by the heater energization start temperature setting means, and the temperatures detected by the evaporator temperature detecting means are compared. When the temperature detected by the evaporator temperature detection means is equal to or lower than the temperature set by the heater energization start temperature setting means, the temperature is detected by the evaporator temperature detection means. And a control unit that sequentially issues an energization instruction signal from the low-temperature defrost heater, and energizes the defrost heater in the order of frost on the evaporator among a plurality of the defrost heaters. As a result, it is possible to prevent the temperature inside the refrigerator from rising and to save power.

Further, heater energization end temperature setting means for previously setting a temperature at which energization of the defrost heater is ended for each temperature detected by the evaporator temperature detection means,
It is determined whether or not the temperature detected by the evaporator temperature detecting means is equal to or lower than the temperature set by the heater energizing start temperature setting means. A calculating unit for determining whether the temperature is equal to or lower than the temperature set by the temperature setting unit, and a temperature detected by the evaporator temperature detecting unit connected to the calculating unit and equal to or higher than a temperature set by the heater energizing end temperature setting unit. And a controller for issuing an instruction signal to energize the defrost heater until the temperature reaches the temperature.The energizing time of the defrost heater is set to a time suitable for the temperature detected by the evaporator temperature detecting means, and the frost of the evaporator is controlled. It is possible to efficiently defrost parts with many parts and prevent a rise in temperature in the refrigerator.

Further, an outside air temperature detecting means such as a thermistor for detecting the outside air temperature around the main body, and a heater energizing end temperature for setting a temperature at which the energization of the defrost heater is terminated in advance for each temperature detected by the outside air temperature detecting means Setting means, determining whether the temperature detected by the evaporator temperature detecting means is equal to or lower than the temperature set by the heater energizing start temperature setting means, and when the heater is energized, the temperature detected by the evaporator temperature detecting means is determined. A calculating unit for determining whether the temperature is equal to or lower than the temperature set by the heater energizing end temperature setting unit, and a temperature detected by the evaporator temperature detecting unit connected to the arithmetic unit and set by the heater energizing end temperature setting unit And a controller that issues an instruction signal to energize the defrost heater until the temperature reaches or exceeds the set temperature. Temperature rise of the effective defrosting was Oven varied depending on the outside air temperature detected by the Kigai temperature detecting means can be prevented.

Further, an operation rate detection means for detecting an operation rate of the compressor, and a heater energization end temperature for setting in advance a temperature at which energization of the defrost heater is ended for each operation rate detected by the operation rate detection means Setting means, determining whether the temperature detected by the evaporator temperature detecting means is equal to or lower than the temperature set by the heater energizing start temperature setting means, and when the heater is energized, the temperature detected by the evaporator temperature detecting means is determined. A calculating unit for determining whether the temperature is equal to or lower than the temperature set by the heater energizing end temperature setting unit, and a temperature detected by the evaporator temperature detecting unit connected to the arithmetic unit and set by the heater energizing end temperature setting unit And a control unit that issues an energization instruction signal to the defrost heater until the temperature reaches or exceeds the set temperature. Temperature rise in the then cabinet effective Defrost changed according to the operating rate of the compressor detected by the rotation rate detecting means can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of Embodiment 1 of a defrosting control device for a cooling device according to the present invention.

FIG. 2 is a refrigeration cycle diagram of the first embodiment of the defrosting control device for the cooling device according to the present invention.

FIG. 3 is a flowchart showing an operation of the defrost control device of the cooling device according to the embodiment;

FIG. 4 is a block diagram of Embodiment 2 of a defrosting control device for a cooling device according to the present invention.

FIG. 5 is a flowchart showing an operation of the defrost control device for the cooling device according to the embodiment;

FIG. 6 is a block diagram of Embodiment 3 of a defrosting control device for a cooling device according to the present invention.

FIG. 7 is a flowchart showing the operation of the defrost control device for the cooling device according to the embodiment;

FIG. 8 is a block diagram of Embodiment 4 of a defrost control device for a cooling device according to the present invention.

FIG. 9 is a flowchart showing the operation of the defrost control device of the cooling device according to the embodiment;

FIG. 10 is a block diagram of Embodiment 5 of a defrosting control device for a cooling device according to the present invention.

FIG. 11 is a flowchart showing the operation of the defrost control device for the cooling device according to the embodiment;

FIG. 12 is a block diagram of a conventional defrost control device for a cooling device.

[Explanation of symbols]

 Reference Signs List 6 compressor 8 power supply 9 timer 10 timer defrost start time setting means 11 heater energization start temperature setting means 12 storage unit 13 first evaporator temperature detection means 14 second evaporator temperature detection means 15 operation unit 15a operation unit 15b operation Unit 15c Operation unit 15d Operation unit 16 Operation unit 16a Control unit 16b Control unit 16c Control unit 16d Control unit 17 First relay 18 Second relay 19 Third relay 20 First contact 21 Second contact 22 Third 23 First defrost heater 24 Second defrost heater 25 Control box 27 Heater energization end temperature contact means 27a Heater energization end temperature contact means 27b Heater energization end temperature contact means 28 Outside air temperature detection means 29 Operating rate detection means

Claims (5)

[Claims] In a cooling device such as a refrigerator or a vending machine, a plurality of evaporators, a plurality of defrost heaters disposed in the evaporator, and a plurality of evaporators around each of the defrost heaters are detected. A storage unit for storing evaporator temperature detecting means such as a thermistor, timer defrost start time setting means, a timer, heater energization start temperature setting means, timer defrost start time setting means, and heater energization start temperature setting means. When the time of the timer connected to the storage unit reaches the time set by the timer defrost start time setting means, the temperature detected by the evaporator temperature detection means is set by the heater energization start temperature setting means. A calculating unit for determining whether the temperature is equal to or lower than the temperature determined by the evaporator, and a temperature detected by the evaporator temperature detecting means connected to the calculating unit. A defrosting control device for a cooling device, comprising: a controller for outputting an energization instruction signal only to the defrost heater when the temperature is equal to or lower than a temperature set by the heater energization start temperature setting means. 2. It is determined whether or not the temperature detected by the evaporator temperature detecting means is equal to or lower than the temperature set by the heater energization start temperature setting means, and the temperatures detected by the evaporator temperature detecting means are compared. When the temperature detected by the evaporator temperature detection means is equal to or lower than the temperature set by the heater energization start temperature setting means, the temperature is detected by the evaporator temperature detection means. The defrosting control device for a cooling device according to claim 1, further comprising a control unit that sequentially issues an energization instruction signal from the defrost heater having a lower temperature. 3. A heater energization end temperature setting unit for setting a temperature at which energization of the defrost heater is ended in advance for each temperature detected by the evaporator temperature detection unit; It is determined whether the temperature is equal to or lower than the temperature set by the heater energization start temperature setting unit, and whether the temperature detected by the evaporator temperature detection unit is equal to or lower than the temperature set by the heater energization end temperature detection unit when the heater is energized. And an instruction signal for energizing the defrost heater until the temperature detected by the evaporator temperature detecting means reaches or exceeds the temperature set by the heater energizing end temperature setting means. The defrosting control device for a cooling device according to claim 1, further comprising a control unit. 4. An external air temperature detecting means such as a thermistor for detecting an external air temperature around the main body, and a heater energizing end temperature for setting in advance a temperature at which energizing of the defrost heater is ended for each temperature detected by the external air temperature detecting means. Setting means, determining whether the temperature detected by the evaporator temperature detecting means is equal to or lower than the temperature set by the heater energizing start temperature setting means, and when the heater is energized, the temperature detected by the evaporator temperature detecting means is determined. A calculating unit for determining whether the temperature is equal to or lower than the temperature set by the heater energizing end temperature setting unit, and a temperature detected by the evaporator temperature detecting unit connected to the arithmetic unit and set by the heater energizing end temperature setting unit 3. The defrosting control device for a cooling device according to claim 1, further comprising a control unit that outputs an energization instruction signal to the defrost heater until the temperature reaches a predetermined temperature or more. 4. 5. An operation rate detection means for detecting an operation rate of the compressor, and a heater energization end temperature setting for setting in advance a temperature at which energization of the defrost heater is ended for each operation rate detected by the operation rate detection means. Means, determine whether the temperature detected by the evaporator temperature detection means is equal to or lower than the temperature set by the heater energization start temperature setting means, and when the heater is energized, the temperature detected by the evaporator temperature detection means is A calculating unit that determines whether the temperature is equal to or lower than the temperature set by the heater energizing end temperature setting unit, and a temperature detected by the evaporator temperature detecting unit connected to the arithmetic unit and set by the heater energizing end temperature setting unit. The defrosting control device for a cooling device according to claim 1 or 2, further comprising a control unit that outputs an instruction signal for energizing the defrost heater until the temperature reaches or exceeds a temperature.