JPH04174278A - Defrosting commanding device for freezing and refrigerating showcase - Google Patents

Abstract

PURPOSE:To simplify wiring work by a method wherein respective freezing and refrigerating showcases are provided with a control unit, receiving a commanding signal from a defrosting command controller to judge the number of judgement given to the commanding signal and controlling the starting and/or finishing of defrosting. CONSTITUTION:When the starting and/or finishing time of defrosting, preset and stored in the setting circuit 4a, has come, the control processing device 4b of a defrosting command controlling device 4 outputs a signal to a transmission circuit 4c. Then, the transmission circuit 4c outputs pulse signals, including the number of judgement and the time of starting and/or finishing of defrosting, to the control units 3 of all showcases 1a, 1b,...1n through a signal transmission line 5a. Next, the receiving circuit 3a of the controlling unit 3 outputs a pulse signal to a deciding circuit 3b while the pulse signal, received in the deciding circuit 3b, is judged by comparing the pulse signal with the number of judgement of the judging circuit 3b whether the defrosting commanding signal is for the showcase or not. When the signal is the commanding signal of the starting of defrosting of the showcase, a control circuit 3c excites a power relay 2 to close a contact 2a and conduct current through a defrosting heater 6 whereby the heater 6 generates heat and defrosting operation is started.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a defrosting instructing device for a plurality of refrigerated freezer showcases having different defrosting start and end times.

[Prior Art] A freezer/refrigerator showcase, for example an oven type one, has a main body with an insulating wall that has an opening for entering and exiting products on the front, and a duct plate inside the main body that serves as a product storage area and a cold air circulation duct. It is divided.

A blower and a cooler are installed in this cold air circulation duct, and the upper end of the duct serves as a cold air outlet located above the opening for entering and exiting products, and the lower end is located below the opening for entering and exiting products. The air sucked in from the suction port by a blower is cooled by a cooler and then blown out from the upper air outlet, and this blown cold air forms a cold air curtain at the opening for product entry and exit, and the cold air is To prevent outside air from entering the product storage with a curtain and at the same time keep the inside of the product storage at a predetermined temperature.

By the way, the air sucked into the duct from the suction port contains outside air and also contains moisture generated from the products inside the warehouse, making it humid, and this humid air flows into the cooler. As a result, this moisture becomes frost and adheres to the cooler, resulting in a decrease in cooling capacity.

Therefore, it is necessary to remove the frost that has adhered to the cooler (defrosting operation is performed at predetermined intervals, but in stores such as supermarkets where multiple frozen and refrigerated showcases are installed, each showcase is When the types of foodstuffs to be stored differ, the set temperature inside the refrigerator differs for each showcase, and as a result, the time to start and end the defrosting operation, that is, the defrost cycle, also differ.

Conventionally, for a plurality of freezer/refrigerator showcases with different defrosting cycles, as a means for each freezer/refrigerator showcase to perform a defrosting operation using the defrosting cycle set for the showcase, for example, as shown in FIG. As shown, multiple frozen and refrigerated showcases (la) (lb)...(1n)
The contact point (2a) of the power relay (2) for controlling the heater is connected in series to the defrosting heater (6) provided in each showcase, and the power relay (2a) for each showcase (la) (lb) - (In) is connected in series. 2) are connected to the contacts (7a) of the timer (7), and each timer (7) is connected to the showcase (la).
(lb)...(1n) The start time and end time of each defrosting operation are set differently.

To perform the defrosting operation in this way, for example, when the cooling operation starts for the freezer/refrigerator showcase (1a), the timer (7) starts counting, and as the cooling operation progresses, the preset defrosting operation starts. When the time comes, the timer (7) counts up, its contact (7a) closes, and the power relay (2) for controlling the heater is energized. As a result, the contact (2a) of the power relay (2) closes and the defrost heater (6)
Electricity is applied to the cooler, which generates heat that melts the frost that has adhered to the cooler.

In this way, defrosting operation is performed, and when the set time has elapsed, the contact (7a) of the timer (7) returns and the power relay (2)
When the power is cut off and it becomes de-energized, its contact (2
a) is opened, #, the power supply to the frost over heater 6) is cut off, the heater is turned off, and the defrosting operation is completed.

The other frozen and refrigerated showcases (1b)...(In) are also equipped with defrosting heaters (6) installed in each of the showcases (1b)...(1n) in the same way as the frozen and refrigerated showcase (la). The defrosting operation is performed by each defrosting cycle by the action of each timer (7) connected to the defrosting cycle.

[Problem to be solved by the invention]

If there are multiple refrigerated/refrigerated showcases installed like this, each with a different defrosting cycle, a timer set to a different time for each showcase can be used as a means of instructing the start and end of defrosting. Therefore, not only the same number of timers as the showcases are required, but also wiring work for connection with each timer for each showcase is required, which requires time and effort.

An object of the present invention is to solve the disadvantages of the conventional example, and to provide a means for instructing the start and end of defrosting for all the frozen/refrigerated showcases even if the defrosting cycles are different for each of the multiple frozen/refrigerated showcases installed. To provide a defrosting instruction device for a frozen/refrigerated showcase that requires only one, reduces the number of wires connected between all showcases and instruction means, and simplifies wiring work.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention provides a defrosting instruction control device in the center of a management room, etc., which sets the defrosting start and end times for each freezer/refrigerator showcase with an identification number for each showcase. It also includes a receiving circuit that receives the instruction signal from the defrosting instruction control device, a determination circuit that determines the discrimination number attached to the instruction signal, and a determination circuit that determines the content of the instruction signal when the determination circuit determines that the number is its own. A control section consisting of a control circuit for controlling the start and end of defrosting is provided in a plurality of freezer/refrigerator showcases with different start and end times of defrosting, and a defrosting instruction control device is connected to a single signal to these plurality of control sections. The gist of this is to connect via a transmission line.

[Effect]

According to the present invention, the instruction signal from the defrosting instruction control device, which sets the defrosting start and end times for all the frozen/refrigerated showcases, is input to the control unit of each showcase. In this case, the instruction signal is input to the control unit of all the showcases via one signal transmission line, so the control unit selects and removes only the one for the showcase from among the input instruction signals. Controls the start and end of frost.

〔Example] Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a circuit diagram showing an embodiment of the defrosting instruction device for a refrigerated showcase of the present invention. In the figure, the same components as those of the conventional example shown in FIG. 2 are given the same reference numerals. It is.

In the figure, (1a) (1b) - (1n) indicate a plurality of frozen and refrigerated showcases installed in stores such as supermarkets, and the showcases (la) (lb)... (I
n) is equipped with a power relay (2) for heater control as before.
) Defrosting heater (6) connected in series to contact (2a) of
is the provision.

The device of the present invention is provided with a control section (3) for relay control connected to this power relay (2), and the control section (3) is connected to the power relay (2).
) is the defrosting instruction control bag described later! (4) is a receiving circuit (
3a) and the received instruction signal is displayed in the relevant showcase (la
) (lb)... (In) is determined by comparing the determination number set here.
b) and a control circuit (3c) that outputs to the power relay (2).
).

In the figure, (4) shows a defrosting instruction and control device that uses a microcomputer installed in a store manager's room, management room, etc., and this defrosting instruction and control device (4) is used to control all of the multiple devices with different defrosting cycles. A setting circuit (4a) that sets and stores each defrosting start time and end time with a discrimination number in advance for the showcase, and a setting circuit (4a) that counts the time and starts and ends defrosting when the defrosting start time and end time are reached. A central processing unit (CPU) (4b) that outputs an instruction to finish defrosting, and a receiving circuit (3a) of a control unit (3) that receives an output from the central processing unit (4b) and sends instruction signals to start and finish defrosting. and a transmitting circuit (4c) that outputs to the.

And showcase (1a) (1b) −(I
n) each control unit (3) (3)...(3) is connected by one or more connecting wires (5b), and any one of them is connected to one showcase, for example, showcase (1a). The connection line (5b) was connected to one signal transmission line (5a), and this signal transmission line (5a) was connected to the transmission circuit (4c) of the defrosting instruction control device (4).

Next, the operation will be explained.

At the same time as the showcases (1a) (1b) - (1n) start cooling operation, the defrosting instruction control device (4) also starts operating, and the central processing unit (4b) starts counting time and (1a) (1b) ・= (1
Regarding n), when the defrosting start and end times preset and stored in the setting circuit (4a) come, the transmitting circuit (4c
).

The transmitting circuit (4c) receives the output from the central processing unit (4b) and sends it to the showcases (1a), (1b)...
(In) is converted into a pulse signal containing a preset identification number and defrosting start and end times, and this pulse signal is sent to all showcases (In) via a signal transmission line (5a). la') (1b)...(1n) is output to the control unit (3).

The receiving circuit (3a) of the control unit (3) of the showcase (1a) (1b) - (1n) outputs this received pulse signal as it is to the judgment circuit (3b), and the judgment circuit (3b) The defrosting instruction signal based on the received pulse signal is transmitted to the showcase (1a) (1b)...(1n)
It is set in the discrimination circuit (3b) to check whether the defrosting instruction signal is for starting or for ending. It is determined and output to the control circuit (3c).

Upon receiving this signal, the control circuit (3c) excites the power relay (2) and closes its contacts (
2a) is closed, the defrosting heater (6) is energized to generate heat, and defrosting operation is started.

On the other hand, if the signal indicates the end of defrosting, the power relay (2) is de-energized and its contact (2a) is opened to stop the power supply to the defrosting machine (6). End frost operation.

Note that the defrosting instruction signal output from the receiving circuit (3a) to the determination circuit (3b) is
)...(1n), the determination circuit (3b) does not output to the control circuit (3C), and the power relay (2) does not operate.

〔Effect of the invention〕

As described above, the defrosting instruction device for frozen/refrigerated showcases of the present invention provides one defrost instruction device for all showcases, even if a plurality of frozen/refrigerated showcases are installed with different defrosting cycles. Since defrosting control is performed using the instruction signal from the defrosting instruction control device, one means of defrosting instruction is sufficient, and one signal transmission line is needed between the defrosting instruction control device and all the showcases. Since it is possible to connect with the defrosting instruction means for each showcase using a separate signal line, the number of signal lines can be reduced and the wiring work can be made simple and inexpensive.

Furthermore, wiring can be easily changed when adding or moving a showcase.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing one embodiment of the defrosting instruction device for a freezer/refrigerator showcase of the present invention, and FIG. 2 is a circuit diagram showing a conventional example. (1a) (1b)...(l n)...Freezer/refrigerator showcase (2)...Power relay (2a)...Contact (3)...Control unit (3a)
...Reception circuit (3b)...Judgment circuit (3C)...
・Control circuit (4) -- Defrosting support control device (4a) -- Setting circuit

Claims (1)

[Claims] A defrosting instruction control device that sets the defrosting start and end times for each freezer/refrigerated showcase with an identification number for each showcase is installed in the center of the management room, etc., and A receiving circuit that receives the instruction signal, a determination circuit that determines the identification number attached to the instruction signal, and a control circuit that controls the start and end of defrosting based on the contents of the instruction signal when this determination circuit determines that the number is its own. A control unit comprising: is provided in a plurality of freezer/refrigerator showcases each having a different defrosting start and end time, and a defrosting instruction control device is connected to these multiple control units via a single signal transmission line. Defrost instruction device for frozen and refrigerated showcases.