JPH0331678A - Controller for showcase - Google Patents

Abstract

PURPOSE:To reduce defrosting frequency during the business time of daytime and prevent temperature rise in a case such as a showcase or the like by a method wherein the defrosting period is set individually in daytime and at night to effect switching operation automatically in accordance with a temperature outside of the case, which is detected by a defrosting period determining means and an outside temperature detecting means. CONSTITUTION:A defrosting mode determining means 28, an average temperature operating means 30 and a defrosting period determining means 31, inputting the signal of a defrosting mode determining means 28, are provided whereby the defrosting period of daytime is switched to the same at night by a first switch 23 and a second switch 24. When the defrosting operation at night, effected by the first switch 23, is set once by a first timer 20 and a second timer 27, the defrosting operation at night may be effected automatically at the same time every days. Further, the period (t13) of defrosting time at night can be changed arbitrarily by the average value of outside temperatures during operation, which is obtained by an outside temperature detecting means 29 and the average temperature operating means 30 whereby defrosting operation may be effected concentratedly at night in accordance with the operating time in daytime.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a control device for controlling the defrosting operation of showcases and the like.

BACKGROUND OF THE INVENTION In recent years, several types of defrosting systems have been used in showcases and the like that control defrosting operations by electronic control.

An example of the conventional control device for a showcase or the like mentioned above will be described below with reference to the drawings.

FIG. 3 is a block diagram of a conventional control device for a showcase, etc., and FIG. 4 is an operation flowchart thereof.

In FIG. 3, 1 is an evaporator temperature detection means for detecting the temperature of the evaporator, and 2 is a defrost cycle timer that also counts the defrost cycle time. Reference numeral 3 denotes defrosting start control means, which receives signals from the evaporator temperature detecting means 1 and the defrosting cycle timer 2 as input. 4
is a defrosting timer that counts the defrosting time, and receives the signal from the defrosting start control means 3 as input. Reference numeral 6 denotes a first control means, which receives signals from the defrost start control means 3 and the defrost timer 4 and controls energization of the defrost heater 6 .

Reference numeral 7 denotes a refrigerator temperature detection means for detecting the temperature inside the refrigerator. 8
The control temperature setting means sets the control temperature target inside the refrigerator.

Reference numeral 9 denotes a comparison means which inputs signals from the chamber temperature detection means γ and the control temperature setting means 8.

Reference numeral 10 denotes a second control means, which receives signals from the first control means 5 and comparison means 9 and controls the operation of the compressor 11.

The operation of the controller for a showcase or the like constructed as described above will be explained below using the operation flowchart shown in FIG.

First, when the power is turned on, the defrosting cycle timer 2 starts operating in step a (this defrosting cycle timer cumulative time is assumed to be 70). Next, in step b, the internal temperature detection means 7 and the control temperature setting means 8 each detect the internal temperature T0.
and the control target temperature T1 are input to the comparison means 9, and in step C, the comparison means 9 calculates the internal temperature T. and the control target temperature T1, and if formula (1) is satisfied, the signal S1 is output to the second control means 10 in step d to turn on the compressor 11; otherwise, the compressor is turned on. 11 is turned off.

To>T1 (1) Next, in step e, the defrosting start control means 3 receives the defrosting cycle timer cumulative time t from the defrosting cycle timer 2.

is input and compared with the defrosting cycle time t1 preset in the defrosting start control means 3. If the expression (2) is satisfied, the logic advances to step f; otherwise, the logic advances to step b.

to≧t1・・・・・・・・・・・・(2)
In step f, the evaporator temperature T2 from the evaporator temperature detection means 1 is input to the defrosting start control means 3, and in step q, the defrosting start control means 3 sets the preset defrosting start temperature T3. In comparison, if formula 3) is satisfied, the logic proceeds to step h; otherwise, the logic proceeds to step a.

T2<T3 (In step h, the defrost start control means 3 outputs the signal S2 to the defrost time timer 4, and the defrost time timer 4 starts counting. (The accumulated time of this defrosting time timer 4 is assumed to be t2.) Next, in step i, the defrosting start control means 3 outputs a signal S3 to the first control means 5,
At the same time as the defrost heater 6 is turned on, the first control means 6 outputs a signal S4 to the second control means 1o, the compressor 11 is turned off, and the L defrosting operation is started. Next, in step j, the defrost time timer cumulative time t2 is inputted from the defrost time timer 4 to the first control means 5, and compared with the defrost time t3 set in advance in the first control means 5. If formula (4) is satisfied, the logic advances to step k for the chief lost heater 6 to 0FFL step a, and otherwise, the logic advances to step i.

t2≧t3 (4) Problems to be Solved by the Invention However, in the conventional configuration, the defrosting cycle time t1, which is preset in the defrosting start control means 3, is changed day and night. Since the defrosting operation is repeated during the daytime when there is a large amount of frost, there is a high possibility that the defrosting operation will be started during the day when there is a large amount of frost, which has the drawback of causing an increase in the temperature inside the showcase etc. during daytime business hours.

The present invention solves the conventional problems by automatically switching the defrosting cycle between day and night, reducing the frequency of defrosting during daytime business hours, and preventing the temperature rise inside showcases, etc. The purpose is to provide a control device for cases, etc.

Means for Solving the Problem In order to achieve this object, the control device for a showcase, etc. of the present invention has a first switch for starting the night operation of the showcase, a second switch for canceling the night operation, and a second switch for controlling the outside temperature. an outside temperature detection means for detecting; an average temperature calculation means for sampling a signal from the outside temperature detection means and calculating an average temperature; an evaporator temperature detection means for detecting the temperature of the evaporator; and the first switch. and a switch input determination means that receives a signal from the second switch as an input, a first timer that receives a signal from the switch input determination means as an input, and a second timer that receives a signal from the first timer as an input. a defrosting mode determining means that receives as input the signals of the switch input determining means and the first timer and the second timer; a defrosting cycle determining means that receives the signals of the average temperature calculating means and the defrosting mode determining means; The defrosting cycle timer receives the signal from the defrosting cycle determining means, the evaporator temperature detecting means, the defrosting cycle timer input signal, and the defrosting control means controls the defrost heater. .

Operation With this configuration, the defrosting cycle can be set separately for daytime and nighttime depending on the outside temperature determined by the defrosting cycle determining means and the outside temperature detecting means, and the defrosting cycle can be automatically switched and operated.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a control device for a showcase, etc. in one embodiment of the present invention, and FIG. 2 is an operation flowchart thereof.

In FIG. 1, reference numeral 20 denotes an internal temperature detection means for detecting the internal temperature of the refrigerator and outputs a signal S1°. 21 is a control temperature setting means for setting a control target temperature and outputs a signal S11. 2
Reference numeral 2 denotes a comparison means which inputs the signals S1o and S11 from the internal temperature detection means 20 and the control temperature setting means 21, and outputs a signal S12.

A first switch 23 outputs a signal S13 indicating the start of night defrosting operation. 24 is a second switch that outputs a signal S14 indicating cancellation of the night defrosting operation.

Reference numeral 26 denotes switch input determination means, which detects the signal S13 and the signal s14 from the first switch 23 and the second switch 24.
is input and the signal S1. , S16 is output. 26 is a first timer which inputs signals S and 5 from the switch input determining means 25 and outputs signals S1□ and S18.

27 is a second timer, which receives the signal S1 from the first timer 26.
Input □ and output signal a+9. 28 is a defrosting mode determining means which inputs the signals S, 8 and S19 from the first timer 26 and the second timer 27, and outputs the signals S2°, S2 . Output. S29 is an outside temperature detection means that detects the temperature outside the refrigerator, and outputs a signal S22. Reference numeral 30 denotes an average temperature calculating means which inputs the signal S21 from the defrosting mode determining means 28 and the signal S22 from the outside temperature detecting means 29 and outputs a signal S23. Reference numeral 31 denotes a defrosting cycle determining means, which inputs the signal S2° and the signal S23 from the defrosting mode determining means 28 and the average temperature calculating means 3Q, and outputs a signal S24. 32 is a defrosting cycle timer which inputs the signal s24 from the defrosting cycle determining means 31 and outputs the signal S2. Output. 33 is an evaporator temperature detection means for detecting the temperature of the evaporator and outputs a signal S26. 3
4 is a defrosting start control means which receives signals S2. , signal s26 are input, and signals S2□ and S28 are output. 36 is a defrosting timer, which receives a signal S2□ from the defrosting start control means 34.
is input and a signal S29 is output. 36 is a second control means which receives signals S28 and S29 from the defrosting start control means 34 and the defrosting timer 35, and outputs signals S3°, S31 .
Output S32.

Here, the defrosting start control means 34. Defrost timer 36 and second
The control means 36 is referred to as a defrosting control means 37.

Reference numeral 38 denotes a defrost heater, which is controlled by pON10FF by a signal S3° from the second control means 36. 39.

4o is a compressor, and the first control means 39 receives the respective signals S12 from the comparison means 22 and the second control means 36.
and 0N by inputting signal S31 and outputting signal S32.
Controlled by 10FF. The second control means is the defrosting start control means 34. Signal S28. from the defrost timer. S29 is input, and signal S32 is output.

The operation of the control device for a showcase or the like constructed as described above will be explained below using the operation flowchart shown in FIG.

First, when the power is turned on, in step 1, the switch input determination 25 receives the signal S3. from the first switch 23. is input, it is determined whether or not the first switch 23 is turned on. If the first switch is turned on, the process proceeds to step 2; otherwise, the process proceeds to step 3.

In step 2, the switch input determination means 26 outputs the signal S15 to the first timer 26, and the first timer 2θ starts (the count time of the first timer 26 is set to time t1o). Next, in step 4, the first
The signal S1□ is output from the timer 26 to the second timer 27, and the second timer 2 ends (the count time of the second timer 27 is set to time t11). Next, in step 5, in the defrosting mode determining means, the switch input determining means 25. First timer 26. Second timer 2
7 to signal S16.7, respectively. Signal S18. Signal S19 is input and the defrost mode is set to night.

Next, in step e, the outside temperature TA from the outside temperature detection means 29 is inputted to the average temperature calculation means 3° as a signal S22.

Next, in step 6', the average temperature calculation means 30 determines the average value TM of the external temperature TA of the signal S22 using the formula shown in equation (4'), and outputs S23.

'ry= f (TA) ・・・・・・・・・・・・
(4') Next, in step 6, the defrosting mode determining means 28
The signal from and the signal S2 from the average temperature calculation means 30
3 is input to the defrosting cycle determining means 31, and the timer time t12 of the defrosting cycle timer 32 is determined by the calculation formula shown in equation (5).
Determine. The timer time t12 at this time is defined as the nighttime defrosting cycle timer time t13.

t −f(TM) ・・・・・・・・・・・・(
6)2 Here, f(TM) is a function determined by the outside average temperature TM output from the average temperature calculating means 3o.

Next, in step 3, the switch input determination means 25
The signal S14 from the second switch 24 is inputted to , and it is determined whether or not the second switch 24 is turned on. If the second switch 24 is turned on, the process proceeds to step 8. Otherwise, the process proceeds to step 9. . Next, in step 8, the signal S16 from the switch input determination means 25 is sent to the first timer 26.
and resets the first timer 26. Next, in step 1o, the first timer 26 sends a signal S1□
is output to the second timer 27, and the second timer 27 is reset. Next, in step 11, the defrosting mode determining means 28 receives the switch input determining means 26゜first timer 2.
6. From the second timer 27, the signals S16. Signal S
18. Signals too. is input, and the defrosting mode is determined to be daytime. Next, in step 12, the defrosting mode determining means 2
8, the υ signal S21 is output to the average temperature calculation means 30,
The outside average temperature TM of the average temperature calculation means 30 is reset.

Next, in step 13, the signal S2° from the defrosting mode determining means 28 is input to the defrosting cycle determining means 31, and the timer time t13 of the defrosting timer 32 is changed to the daytime defrosting cycle timer time t1.
Set to 4.

Next, in step 9, the signal S18 from the first timer 26 is input to the defrosting mode determining means 28, and it is checked whether the first timer 26 is counting or in the reset state. If it is in the reset state, the logic advances to step 11.

Next, in step 14, the signal S24 is output from the defrosting cycle determining means 31 to the defrosting cycle timer 32, and the defrosting cycle timer 32 starts counting (timer time t13).

Next, in step 16, the internal temperature detection means 2o and the control temperature setting means 21 input the signal S1° and the signal S11 to the comparison means 22, respectively.

The internal temperature at this time is T1°, and the control target temperature is T11. In step 16, the internal temperature T1° and the control target temperature T11 are compared, and if the equation 6) is satisfied, the process proceeds to step 17; otherwise, the process proceeds to step 18.

Tlo>T11 ・・・・・・・・・・・・(6
) In step 17, the signal S12 is sent from the comparison means 22 to the first control means 39, and the signal S3 is sent from the first control means 39 to the first control means 39.
3 is output to the compressor 40, turning the compressor 40 ON.

Next, in step 18, the comparison means 22 receives the signal "1".
2 is outputted to the first control means 39, and a signal s33 is outputted from the first control means 39 to the compressor 4o, turning off the compressor 4o. Next, in step 2o, the defrosting start control means 34 receives a signal S26 from the defrosting cycle timer.
is input, and it is determined whether the timer time '13 of the defrosting cycle timer 32 satisfies the formula (A) (K is a constant).

t13〉K1 ・・・・・・・・・・・・(f
) or 7k), the count tf of the timer time t13 of the defrosting cycle timer 32 is stopped in step 21, the timer time t13 is reset, and the process proceeds to step 22.
(7) If the formula is not satisfied, the logic returns to step 16.

Next, in step 22, the signal S26 is input from the evaporator temperature detection means 33 to the defrosting start control means 34. The temperature of the evaporator at this time is set to "12."Then, in step 23, the evaporator temperature T12 is compared with the defrosting start temperature "13" preset in the defrosting start control means 34.
), the logic proceeds to step 24; otherwise, the logic proceeds to step 1.

T12〈T13 ・・・・・・・・・・・・(8
) In step 24, the defrost start control means 34 outputs the signal ~a to the defrost timer 36, and the defrost timer 36
(The cumulative time of the defrost timer 36 is set to +16). Next, in step 25, a signal S28 is outputted from the defrost control means 34 to the second control means 36, and a signal S3) is outputted from the second control means 36 to the defrost heater 3. While energizing, the second control means 36 to the first control means 39
The first control means 39 outputs a signal S31 to the compressor 40, and the first control means 39 outputs a signal S33 to the compressor 40 to stop the compressor 40 and start defrosting operation. Next, in step 26,
The signal S29 from the defrost timer 35 is input to the second control means 36, and the integrated time t18 of the defrost timer 36 is set to the defrost time preset in the second control means 36, compared with 2, and the formula 9) If satisfied, in step 27, the second control means 36 outputs a signal S30 to the defrost heater 38 to stop the defrost heater 38, and the logic advances to step 28; otherwise, the logic advances to step 25.

'16≧2 (9) In step 28, the second timer 27 receives the signal S1
9 to the defrosting mode determining means 28, and the second timer 2
The count time t11 of 7 and the time preset in the defrosting mode determining means 28 are compared with 3, and if the formula 01 is satisfied, the second timer 27 is reset and the timer 27 is reset in step 2.
9, each time the logic advances to step 9.

'11≧3 ......01 Next, in step 29, the signal S18 from the first timer 26 is input to the defrosting mode determining means 28, and the count time of the first timer 26 is Compare t1° with the time set in advance in the defrosting mode determining means 29 and 4 (24 hours),
If the θη formula is satisfied, in step 30, the average temperature calculation means 3o calculates the data TA and the average temperature T.
At the same time as resetting M, the first timer is counted from 0 and the logic advances to step 9, otherwise the logic advances to step 13.

tl. ≧4 ・・・・・・・・・・・・(+1
) As described above, the signals from the first switch 23 and the second switch 24 that input the start and cancellation of the night defrosting operation, the outside temperature detection means 29 that detects the outside temperature of the refrigerator, and the outside temperature detection means 29 are detected. An average temperature calculation means 3o that samples S22 and calculates the average temperature, an evaporator temperature detection means 33 that detects the temperature of the evaporator, and a switch input determination using signals from the first switch 23 and the second switch 24 as inputs. Means 25
and a first input signal which receives the signal from the switch input determination means 26.
a timer 26, a second timer 27 which receives the first timer 26 as an input, a switch input determining means 28, and a defrosting mode determining means 28 which receives the signals of the first timer 26 and the second timer 27 as inputs. and a defrosting cycle determining means 3 which receives signals from the average temperature calculating means 3o and the defrosting mode determining means 28.
1 allows the first switch 23 and the second switch 24 to switch the defrosting cycle between day and night, and also allows the first timer 26 and the second timer 27 to switch the defrosting cycle once.
When the night defrosting operation is set by the switch 23,
Night defrosting operation can be performed automatically at the same time every day. Furthermore, the nighttime defrosting time cycle t13 can be arbitrarily changed from the average value of the outside temperature during interlayer operation to the outside temperature detection means 29 and the average temperature calculation means 3o. Accordingly, the defrosting operation can be performed intensively, the frequency of defrosting during the day can be reduced, and the temperature inside the showcase or the like can be prevented from rising.

Effects of the Invention As described above, the present invention provides a first switch for starting nighttime operation of a showcase or the like, a second colored light switch for releasing the display, an outside temperature detection means for detecting the temperature outside the refrigerator, and an outside temperature detection means. evaporator temperature detection means; switch input determination means that receives signals from the first switch and the second switch; and switch input determination means. A first timer receives the signal from the first timer as an input, and a second timer receives the signal from the first timer as an input.
a timer, a switch input determining means, and a defrosting mode determining means that receives signals from the first timer and the second timer;
A defrosting cycle determining means that receives the signals from the average temperature calculating means and the defrosting mode determining means, a defrosting cycle timer that receives the signals from the defrosting cycle determining means, an evaporator temperature detecting means, and a defrosting cycle timer. By providing a defrosting control means that controls the defrost heater using the signal as input, the defrosting cycle can be switched between day and night by inputting a switch, and once set by the operation of a timer, night defrosting operation can be performed automatically at the same time every day. In addition, the nighttime defrosting cycle can be changed according to the compressor operation time during the day, so defrosting is performed intensively at night with an appropriate defrosting cycle, reducing the frequency of defrosting during the day, and reducing the amount of time required to store the inside of a showcase, etc. Can prevent temperature rise,
This realizes a control device for showcases, etc.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a control device for a showcase, etc. in an embodiment of the present invention, FIG. 2 is an operation flowchart of a control device for a showcase, etc. in an embodiment of the present invention, and FIG. 3 is a conventional showcase. A block diagram of a control device such as
FIG. 4 is an operation flowchart of a conventional control device for a showcase or the like. 23...first switch, 24...second switch, 26...switch input determination means, 26...first timer, 27... . . . Second timer, 28 . . . Defrosting mode determining means, 29
. . . External temperature detection means, 30 . . . Average temperature calculation means, 31 . . . Defrosting cycle determination means, 3
2... Defrost cycle timer, 33... Evaporator temperature detection means, 37... Defrost control means, 38.
...Defrost heater. Straw 2 Diagram (1) (3) Evening Diagram ■ Diagram

Claims (1)

[Claims] A first switch that starts night operation of a showcase, etc., a second switch that releases it, an outside temperature detection means that detects the temperature outside the refrigerator, and a signal from the outside temperature detection means that samples the signal and calculates the average temperature. an average temperature calculating means to be calculated; an evaporator temperature detecting means; a switch input determining means receiving signals from the first switch and the second switch; and a first determining means receiving the signals from the switch input determining means. A timer and
a second timer receiving the signal from the first timer; a switch input determining means; a defrosting mode determining means receiving the signals from the first timer and the second timer; an average temperature calculating means; and a defrosting mode. A defrosting cycle determining means receives the signal from the determining means as an input, a defrosting synchronous timer receives the signal from the defrosting cycle determining means as input, and a defrosting circuit receives the signals from the evaporator temperature detecting means and the defrosting cycle timer as inputs. A control device for a showcase, comprising a defrosting control means for controlling a heater.