JPH02233974A - Control device for show case - Google Patents

Abstract

PURPOSE:To prevent the increase of the temperature in the chamber of a show case by performing defrost concentratedly during the night by providing s defrost period deciding means to input a timer signal from a switch input deciding means, a vaporizer temperature detecting means, and a defrost control means to input a signal from a defrost period timer and control a defrost heater. CONSTITUTION:The device comprises a first switch 20 to start and stop night operation of a show case, a switch input deciding means 22 to input a signal from a second switch 21, a second timer 24 to input a signal from a first timer 23 for inputting a signal from the deciding means 22, a defrost period deciding means 25 to input signals from the input deciding means 22 and the timer 24, a vaporizer temperature detecting means 27 to input a signal from the deciding means 25 and detect the temperatures of a defrost period timer 26 and the vaporizer, and a defrost control means 31 to input signals from the detecting means 27 and the timer 26 and control a defrost heater 32. This constitution switches daytime and night defrost periods, and enables execution of automatic night defrost operation at one and the same time every day when setting is made once, resulting in reduction of a defrost frequency during the daytime and prevention of the increase of the temperature-in-chamber of a show case.

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, some types of defrosting operations have been used in showcases and the like using electronic control.

An example of the conventional showcase control device described 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. 2 is a defrost cycle timer that also counts the defrost cycle time. 3 is a defrosting start control means which receives signals from the evaporator temperature detecting means 1 and the defrosting cycle timer 2; A defrosting timer 4 counts the defrosting time, and receives the signal from the defrosting start control means 3 as an input. Reference numeral 6 denotes a first control means, which inputs signals from the defrosting start control means 3 and the defrost timer 4, and controls 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 value inside the refrigerator. Reference numeral 9 denotes a comparison means which inputs signals from the chamber temperature detection means 7 and the control temperature setting means 8.

Reference numeral 10 denotes a second control means which includes the first control means 6 and the comparison means 9.
The congressor 11 is controlled by inputting the signal.

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 defrost cycle timer starts operating in step a (this defrost cycle timer cumulative time is t).
. ). Next, in step b, the internal temperature T is determined by the internal temperature detection means 7 and the control temperature setting means 8, respectively. and the control target temperature T1 are input into the comparison means 9, and step C
Compare the internal temperature T and control target temperature T at 1,000 steps 9.
1 is compared, and if formula (1) is satisfied, the second
The signal S1 is output to the control stage 1o of the compressor 1.
1 is ONL, and in other cases, the compressor 11 is turned OFF.

T)T・・・・・・・・・・・・・・・
... (1) O1 Next, in step e, the defrosting start control means 3 receives the defrosting cycle timer 2 and the defrosting cycle timer integrated time t.

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.

1o≧t1 ・・・・・・・・・・・・・・・
...(2) In the positive step, the evaporator temperature T2 is input from the evaporator temperature detection means 1 to the defrosting start control means 3, and in step q, the evaporator temperature T2 is inputted to the defrosting start control means 3, which has been set in advance. Compared with the defrosting start temperature T3 (3
), the logic proceeds to step h; otherwise, the logic proceeds to step d.

T (T ・・・・・・・・・・・・・・・・・・
...(3) In step h, the defrosting start control means 3
Then, a signal S2 is output to the defrosting time timer 4, and the counting of the defrosting time timer 4 is started (the integrated time of the defrosting time timer 4 is assumed to be t2). Next, in Nutep 1, the defrost start control means 3 outputs a signal S3 to the first control stage 6, turns on the defrost heater 6, and at the same time outputs a signal from the first control means 5 to the second control means 10. S4 is output, the compressor 11 is turned off, and defrosting operation is started. Next, in step j, the defrosting time timer integrated time t2 is input from the defrosting time timer 4 to the first control means 6, and the defrosting time t3 set in advance in the first control means 5 is inputted.
If the expression (4) is satisfied, the differential opening heater 6 is turned off in step k and the logic proceeds to step a. Otherwise, the logic proceeds to step 1.

t2≧t3 ・・・・・・・・・・・・・・・
(4) Problems to be Solved by the Invention However, in the above conventional configuration, the defrosting start control means 3
Since both day and night operation are repeated every preset defrosting cycle time t, there is a higher possibility that defrosting operation will start during the day when there is a large amount of frost, making it a showcase during daytime business hours. This had the disadvantage of causing an increase in the temperature inside the refrigerator.

The present invention solves the above-mentioned conventional problems, and is a showcase that automatically switches the defrosting cycle between day and night, reduces the frequency of defrosting during daytime business hours, and prevents the temperature inside the showcase from rising. The purpose is to provide a control device such as the following.

Means for Solving the Problem In order to achieve this object, the control device for a showcase, etc. of the present invention includes a first switch, a second switch, and a first switch, respectively, for starting and canceling the night operation of the showcase, etc. and a switch input determination means which receives a signal from the second switch as an input, a first timer which receives a signal from the switch input determination means as an input, and a second timer which receives a signal from the first timer as an input. a defrosting cycle determining unit which receives the signals from the switch input determining unit and the second timer; a defrosting cycle timer which receives the signals from the defrosting cycle determining unit; and an evaporator which detects the temperature of the evaporator. device temperature detection means;
The apparatus is configured to include unboxing control means that receives signals from the evaporator temperature detection means and the defrost cycle timer and controls the defrost heater.

Operation With this configuration, the defrosting cycle can be set separately for day and night by the defrosting cycle determining 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 process diagram of a control device such as a sycamore in one implementation of the present invention, and FIG. 2 is an operational flowchart thereof.

In FIG. 1, 20 is a first switch for inputting the start of the nighttime defrosting operation, and 21 is a second switch for inputting the cancellation of the nighttime defrosting operation. Reference numeral 22 denotes a switch input determination means which inputs signals from the first switch 20 and the second switch 21. A first timer 23 receives the signal from the switch input determining means 22 as an input. A second timer 24 receives the signal from the first timer 23 as an input. Reference numeral 26 denotes a defrosting cycle determining means to which the signals of the switch determination stage 22 and the second timer 24 are input. A defrosting cycle timer 26 receives the signal from the defrosting cycle determining means 25. 27 is an evaporator temperature detection means for detecting the temperature of the evaporator.

Reference numeral 28 denotes defrosting start control means, into which signals from the defrosting cycle timer 26, evaporator temperature detecting means 27, and defrosting cycle determining means 25 are input. A defrosting timer 29 receives a signal from the defrosting start control means 28. 30 is a first control means which inputs signals from the defrost start control means 28 and the defrost timer 29 (the dew start control means 28 and the defrost timer 29, and the first control means 30 is the defrost control means). 31) and controls the defrost heater 32.

Reference numeral 33 indicates an internal temperature detection means for detecting the temperature within the refrigerator, and reference numeral 34 indicates a control temperature control means for setting a control target temperature. 36
is a comparison means, which inputs signals from the chamber temperature detection means 33 and the control temperature control means 34. 36 is a second control means, which inputs the signals of the comparison stage 36 and the first control means 30;
control the compressor.

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. 2.

First, when the power is turned on, in step 1, the switch input determining means 22 determines whether the first switch 2o is ON or not. Proceed to step 6. Step 2
At this point, the switch input determining means 22 outputs the υ signal S1o, and the first timer starts (the first timer cumulative time is set to t1o). Next, in Nuteg 3,
A signal S11 is output from the first timer 23 to the second timer 24, and the second timer starts (the second timer cumulative time is set to t11). Next, in the Nutep 4, the signal from the switch input determining means 22 is input to the defrosting cycle determining means 26, and the defrosting cycle timer 26 is set to night mode (this is referred to as night defrosting cycle timer time). The defrosting cycle timer time t12 set in the start control means 28 is set to the night defrosting cycle timer time t13, and in step 6, the defrosting cycle timer 26 is started (this defrosting cycle timer cumulative time is set as t15). do). and Nutenov 11
Proceed to (start cooling operation).

In step 6, the switch input determination step 22 determines whether or not the second switch 21 is turned on, and if the second switch is turned on, the process proceeds to step 7.
Go to 0. In step 7, the switch input determining means 22 outputs a signal S1o' to reset the first timer. Next, in step 8, the first timer 2
3, a signal S11' is output to the second timer 24,
Reset the second timer. Next, in step 9, a signal is input from the switch input determination means 22 to the defrosting cycle determining means 25, and the defrosting cycle timer 26 is determined to be in daytime mode (this is referred to as daytime defrosting cycle timer time). The defrosting cycle timer time t12 set in the start control means 28 is set to the daytime defrosting cycle timer time '14, and step 6
(Here, the relationship between the daytime defrosting cycle timer time t14 and the nighttime defrosting cycle timer time t is set so that t14>t13).

In step 10, the defrosting cycle determining means 26
The signal from the timer 23 is input, and it is checked whether the first timer is counting or in the reset state. If it is counting, the logic advances to step 4, and if it is in the reset state, the logic advances to step 9. .

In step 11, the internal temperature T1 and the control target temperature T11 are input from the internal temperature detection means 32 and the control temperature setting means 33 to the comparison means 34, and in step 12, the internal temperature T1o and the control target temperature The target temperature T11 is compared, and if the formula (5) is satisfied, a signal S12 is outputted to the second control means 1o in step 13, and the compressor 37 is turned on; otherwise, the compressor 37 is turned off. do.

T1o>T1, ・・・・・・・・・・・・・・・
(5) Next, in step 14, input the defrost cycle timer cumulative time t16 from the defrost cycle timer 2e to the defrost start control unit 28, and in step 4 or 6 input the defrost cycle timer cumulative time t16 to the defrost start control unit 28 in advance. Set defrost cycle timer time'
12, and if formula (6) is satisfied, step 1
5, otherwise proceed to step 1.

t15≧t12 ・・・・・・・・・・・・・・・
...(6) In step 16, the evaporator temperature detection means 27 inputs the evaporator temperature "12" to the defrosting start control means 28, and in the step 16, the evaporator temperature "12" is inputted to the defrosting start control means 28.
In step 8, the defrosting start temperature T13 is compared with the preset defrosting start temperature T13, and if the equation (7) is satisfied, the process proceeds to step 17. Otherwise, the logic proceeds to step 1.

T (T ・・・・・・・・・・・・・・・
(7) In step 17, the defrosting start control means 28
The signal S13 is then output to the defrosting timer 29, and the counting of the defrosting timer 29 is started (the accumulated time of this unboxing timer 29 is set as t16). Next, in step 18, a signal S is sent from the silk removal start control means 28 to the first control means 3o.
14, turns on the defrost heater 32, and sends a signal S from the first control means 32 to the second control means 36.
1. is output, the compressor 37 is turned OFF, and defrosting operation is started. Next is Su? defrost timer 29 in step 18
The defrost timer cumulative time t16 is inputted to the first control means 30, and compared with the defrost time t1■ set in advance in the first control means 30. If the expression (8) is satisfied, step At 2o, defrost heater 32 is turned FF.
L, proceed to step 21; otherwise, proceed to step 18;

'16 ≧ t1■ ・・・・・・・・・・・・
(8) In step 21, the second timer cumulative time '11 is input from the second timer 24 to the defrosting cycle determining means 25, and the defrosting cycle determining means 2 is set in advance.
5, and if the equation (9) is satisfied, the logic proceeds to step 22. Otherwise, the logic proceeds to step 1.

t11 ≧ t1B ・・・・・・・・・・・・
(9) Next, in step 22, the first timer cumulative time t1o is input to the defrosting cycle determination stage 26, and the time '1 preset in the defrosting cycle determining means 26 is input.
9 (24 hours) and if the formula 0 is satisfied, proceed to step 1. Otherwise, proceed to step 9.

t1. ≧t i 9 (24 hours)・・・・・・
...OQ As mentioned above, the first switch 20 and the second switch 21 input the start and release of the night defrosting operation, and the switch that receives the signals of the first switch 2o and the second switch 21 as input. an input determination means 22, a first timer 23 which receives the signal from the switch input determination means 22, a second timer 24 which receives the signal from the first timer 23, and a switch input determination means 22 and the first timer 24; By providing the defrosting cycle determining means 25 which receives the signals of the timer 23 and the second timer 24, the defrosting cycle between day and night can be switched by the first switch 20 and the second switch 2.
Once the timer 23 and the second timer 24 are set by the first switch 21, night defrosting operation can be performed automatically every day. The first step to start and release the rotation is to reduce the temperature rise in the showcase, etc.
a switch and a second switch; a first switch and a second switch;
The signal from the switch is input. a switch input determining means; a first timer receiving a signal from the switch input determining means; a second timer receiving a signal from the first timer; a switch input determining means and a second timer; The defrosting cycle determining means receives the signal from the defrosting cycle determining means, and the defrosting cycle determining means receives the signal from the defrosting cycle determining means. By providing an evaporator temperature detection means for detecting the defrost cycle timer and the temperature of the evaporator, and a defrost control means for controlling the defrost heater by inputting the signals of the evaporator temperature detection means and the defrost cycle timer. The defrosting cycle between day and night can be changed by switch input, and once set, the defrosting cycle can be switched between day and night, and once set, the defrosting operation at night can be automatically performed at the same time every day. The purpose of the present invention is to realize a control device for a showcase, etc., which can reduce the internal temperature of the showcase, etc. and prevent the temperature inside the showcase, etc. from rising.

[Brief explanation of the drawing]

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. 20...first switch, 21...second switch, 22...switch input determination means, 23...first timer, 24... . . . Second timer, 26 . . . Defrost cycle determining means, 26
... Defrost cycle timer, 2 completion... Evaporator temperature detection means, 31 ... Defrost control means, 32.
...Defrost heater. Name of agent: Patent attorney Shigetaka Awano and one other person Figure 1 / I (Zone 1) Figure 1

Claims (1)

[Claims] A first switch and a second switch, respectively, for starting and canceling nighttime operation of a showcase, etc., a switch input determination means that receives signals from the first switch and the second switch, and the switch input determination means a first timer receiving a signal from the first timer; a second timer receiving a signal from the first timer; and a defrosting cycle determining means receiving signals from the switch input determining means and the second timer. , a defrosting cycle timer that receives the signal from the defrosting cycle determining means as input, an evaporator temperature detecting means that detects the temperature of the evaporator, and a defrosting cycle timer that receives the signals from the evaporator temperature detecting means and the defrosting cycle timer as input. , and a defrost control means for controlling a defrost heater.