KR19980022386U - Defroster of refrigeration showcase - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

Defroster of refrigeration showcase

2. The technical problem the invention is trying to solve

In order to solve the problem of damage to the display products caused by the defrost overlap in the conventional refrigeration showcase having two defrost circuits and the increase in manufacturing cost due to the use of a defrost timer having two C contacts.

3. Summary of solution of design

Defrost timer 100 for generating a control signal for periodically controlling the freezing and defrosting; A control unit for generating a relay control signal for selectively controlling the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106 according to the operation of the defrost timer 100; 101); A relay unit which is switched according to a control signal generated by the controller 101 to selectively drive the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106 ( 102).

4. Important uses of the devise

Applied to control refrigeration and defrost in refrigeration showcases with two compressors and two evaporators.

Description

Defrosting apparatus of refrigerated showcase

In general, the showcase is to maintain the cooling and freezing while displaying the product so that the soft drinks, ice cream and meat can be seen from the outside, this is made by the cooling circuit, the freezing cycle of the refrigerant circuit, in particular the evaporator of the refrigerant circuit During the heat exchange, the temperature is maintained while absorbing heat inside the freezing and refrigerating compartments.

That is, the low temperature is obtained by heat exchange between the evaporator heat and the outside air temperature. At this time, frost is caused on the surface of the evaporator by the difference between the heat of the evaporator and the outside air temperature.

Therefore, when driving of the refrigerant cycle is stopped, defrosting is performed to remove frost for a predetermined time. The defrosting means at this time defrosts the frost generated on the surface of the evaporator.

A conventional defrosting apparatus for defrosting as described above is shown in FIGS. 1 to 3.

First, the defrosting apparatus shown in FIG. 1 is an example provided with two defrosting circuits separately handling one compressor and an evaporator in a refrigeration showcase using two compressors and two evaporators.

That is, the first defrost timer 1 for defrosting, the first compressor 2 for compressing the refrigerant in accordance with the operation of the first defrost timer 1, and the switching operation of the first defrost timer 1 According to the first defrost heater (3) and the first drain heater (4), and the first overload switch for turning off the first defrost heater (3) and the first drain heater (4) in case of overload ( 5) and a thermostatic switch 6 for turning off the operation of the first compressor 2 when the first compressor 2 is overheated, and the other defrost circuit comprises a second defrost circuit for defrosting. The defrost timer 7, the second compressor 8 for compressing the refrigerant according to the switching operation of the second defrost timer 7, and the defrosting function according to the switching operation of the second defrost timer 7 are performed. The second defrost heater 9 and the second drain heater 10, the second overload switch 11 for turning off the second defrost heater 8 and the second drain heater 10 in case of overload; 2 It consists of a thermostatic switch 6 for turning off the operation of the second compressor 10 when the compressor 10 is overheated.

The first embodiment of the defrosting apparatus of the conventional refrigeration showcase configured as described above operates as follows.

First, in the first defrost circuit, when the first defrost timer 1 is turned on to operate, the micro switch is connected to the contact A. The first compressor 2 is turned off, and the contact A is turned off. The first defrost heater 3 and the first drain heater 4 operate by the power supply through the defrosting function.

Thereafter, when the first overload switch 6 is turned off, the first defrost timer 1 is also turned off, and at the same time, the micro switch is connected to the B contact NC, which is the original position, so that the first defrost heater 3 and the first drainage water are discharged. The heater 4 is turned off, and the first compressor 2 is driven again.

In addition, the second defrost circuit is also operated by the control of the second defrost timer 7 in the same manner as the above-described first defrost circuit, where the first and second defrost timers 1 and 7 operate separately. .

Next, Figure 2 is a second embodiment of a defrosting apparatus of a conventional refrigeration showcase.

As shown, the components are the same as those of the first embodiment, except that the first defrost timer 1 and the second drain heater 10 are connected in series, and the second defrost timer 7 is connected. And the first drain heater 4 are connected in series, wherein the resistances of the first and second defrost timers 1 and 7 are large and the resistances of the first and second drain heaters 4 and 10 are relatively high. It is small and does not affect the operation of the first and second defrost timers 1 and 7.

The operation of the second embodiment of the conventional defrost apparatus having such a configuration will be described below.

First, when the first defrost timer 1 operates, the micro switch is connected to the contact point NO. In this case, the potential of the first defrost timer 7 is the same as that of the first defrost timer 1. The second defrost timer 7 is turned off.

Therefore, the first compressor 3 is turned off by the operation of the first defrost timer 1, and only the first defrost heater 3 and the first drain heater 4 operate to perform the defrost function. Then, when the first overload switch 5 is turned off, the first defrost timer 1 is also turned off, and the micro switch is connected to the B contact NC in its original state so that the first compressor 2 is driven and the first defrost heater is operated. (3) and the first drain heater 4 are turned off.

Similarly, when the second defrost timer 7 is operated, the first defrost timer 1 is turned off by the coin phase. Hereinafter, the second compressor 8, the second defrost heater 9, and the second drain heater 10 are operated. Operation of the same as the operation of the first defrost circuit described above.

That is, in the second embodiment, the same potentials of the first and second defrost timers (1) and (7) are made so that when one timer operates, the other timer is turned off. Defrost duplication will be prevented.

3 is a third embodiment of the conventional defrosting apparatus.

As shown in the figure, a fuse 12 for shutting off the power input during a momentary overvoltage, a defrost timer 13 for controlling the defrosting operation, and a front and rear dew prevention for preventing dew occurring in the front and rear parts First and second compressors for compressing the refrigerant according to the operation of the heaters 14 and 15, the front and rear condenser fan motors 16 and 17 for driving the front and rear condenser fans. The compressor 18 and 19 and the front defrost heater 20 and the front evaporation heater 21 for front evaporation and defrosting are controlled according to the operation of the defrost timer 13, and the heater power is driven when the heater is overheated. The first overload relay 22, the front drain heater 23, and the defrost timer 13 are controlled according to the operation of the defrost timer 13 to turn off the rear defrost heater 24 and the rear evaporation heater ( 25) and a second overload relay for turning off the heater power supply when the heater is overheated. Thermostat, rear drainage heater 27, and thermostatic for turning off the operation of the first and second compressors 18 and 19 when the first and second compressors 18 and 19 are overheated. It consists of a switch 28.

The operation of the third embodiment of the conventional defrosting device configured as described above is as follows.

The third embodiment is a defrosting device which further improves the problems of the first and second embodiments described above. In particular, two compressors and two microswitches are simultaneously switched using the defrost timer 13 having two C contacts. It is a device that performs compression and defrost function by controlling two evaporators at the same time.

However, the first to third defrosting apparatus of the conventional refrigeration showcase as described above has caused the following problems.

That is, in the first embodiment, the first and second defrost circuits operate separately and perform compression and defrost functions. When the first and second defrost circuits perform defrosting in duplicate, the display goods are increased due to the increase in showcase high temperature. There was a problem of being damaged.

In addition, the second embodiment is a circuit to solve the problem of the first embodiment described above, but when the two timers enter the defrost at the same time, the entire refrigerator is turned off, causing a problem that the display goods are damaged.

In addition, the third embodiment further improves the above-mentioned problems of the first and second embodiments, but the circuit is fused or degraded due to the limitation of the force at which the contact operates by using a timer having two C contacts. There is a problem of malfunction, and moreover, the cost of manufacturing increases due to the use of a timer having two C contacts.

Therefore, the present invention has been proposed to solve the above problems of the conventional refrigeration showcase defrosting apparatus as described above, and an object of the present invention is to control the defrosting of two evaporators with a defrost timer having a C contact point. It is to provide a defrosting device of the refrigeration showcase to prevent the overall manufacturing cost by preventing the fusion and deterioration of the micro switch contact, and simplify the circuit configuration.

Technical means for achieving the object of the present invention, the defrost timer for periodically controlling the refrigeration and defrosting; A controller for generating a relay control signal for controlling first and second compressors and first and second defrost heaters according to the operation of the defrost timer; Switched according to the control signal generated by the control unit is configured to supply and cut off the driving power of the first and second compressors and the first and second defrost heater to selectively drive the compressor and defrost heater.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a first embodiment of a defrosting apparatus of a conventional refrigeration showcase,

Figure 2 is a second embodiment of a defrosting apparatus of a conventional refrigeration showcase,

3 is a third embodiment of a defrosting apparatus of a conventional refrigeration showcase;

4 is a defrosting device circuit diagram of a refrigeration showcase according to the present invention,

FIG. 5 is a detailed circuit diagram of a defrosting control part of FIG. 4;

6 is an operation timing diagram of each part of FIG. 4.

Explanation of symbols on the main parts of the drawings

100: defrost timer 101: control unit

102: relay unit 103, 104: first and second compressor

105, 106: First and second defrost heaters

4 is a circuit diagram of a defrosting apparatus of a freezing showcase according to the present invention.

As shown, the defrost timer (100) is one C contact for periodically controlling the freezing and defrosting; The controller 101 generates a relay control signal for controlling the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106 according to the operation of the defrost timer 100. Wow; Switched according to the control signal generated by the control unit 101 to supply and cut off the driving power of the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106 A relay unit 102 for selectively driving the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106; The thermostatic switch 107 is configured to turn off the operation of the first and second compressors 103 and 104 when the first and second compressors 103 and 104 are overheated.

In the above, the defrost timer 100 is characterized by consisting of a motor timer for switching the micro switch having a single C contact by an external electrical signal.

In addition, the controller 101 includes a transformer 101a for converting the supplied power to an arbitrary level, a first bridge diode 101b for full-wave rectifying the secondary output voltage of the transformer 101a, and the first bridge. A smoothing capacitor C1 for smoothing the output voltage of the diode 101b, a constant voltage section 101c for making the DC voltage smoothed in the smoothing capacitor C1 to a constant voltage of a predetermined level (DC12V), and the defrost timer 100 The second bridge diode (101d) for full-wave rectifying the B contact (NC) output voltage of the micro-switch and the primary output voltage of the transformer (101a) and the output voltage of the second bridge diode (101d) A photocoupler 101e for generating a signal and converting the generated light into an electrical signal, a signal generated by the photocoupler 101e as a clock, and a signal output from the constant voltage unit 101c as a set terminal. To generate a relay control signal. Is switched on / off by a voltage divided by the resistors R4 and R5 for dividing a signal output from the JK flip-flop 101f, the JK flip-flop 101f, and the resistors R4 and R5. And a switching element 101g for simultaneously controlling a plurality of relays in the relay unit 102.

In addition, the relay unit 102 is switched on / off according to a control signal output from the control unit 101, so that the first and second compressors 103 and 104 and the first and second defrost heaters 105 ( And first to third relays 102a to 102c for selectively driving the compressor and the defrost heater by supplying and cutting off the driving power of 106.

When explaining the operation of the defrosting apparatus of the freezing showcase according to the present invention configured as described above based on Figures 4 to 6 as follows.

First, the defrost timer 100 having one C contact switches an internal micro switch to periodically perform a defrost function according to the inflow of an external electrical signal, where the periodic operation timing of the defrost timer 100 is It is the same as FIG.

In this case, the controller 101 may control the first to second compressors 103 and 104 and the first and second defrost heaters 105 and 106 to selectively control the first to third in the relay unit 102. The relays 102a-102c are controlled simultaneously.

That is, as shown in FIG. 5, the controller 101 converts the input driving power into the transformer 101a and propagates the AC voltage converted by the transformer 101a to the first bridge diode 101b. It rectifies and smoothes with a smoothing capacitor (C1) to make a DC voltage (DC). Thereafter, the DC voltage generated by the constant voltage unit 101c is made a constant voltage of a constant level (DC12V) and supplied to each part of the circuit as an operating power source.

In addition, the second bridge diode 101d performs full-wave rectification of the voltage flowing to the primary side of the transformer 101a and the voltage flowing to the B contact NC of the micro switch in the defrost timer 100, and the output voltage The driving of the photocoupler 101e is controlled to generate an electrical signal (pulse).

The electrical signal generated in this way is input to the JK flip-flop 101f as a clock, and the JK flip-flop 101f receives the signal generated by the constant voltage unit 101c through the set terminal S and receives the input. In synchronization with a clock, a signal input to the data terminals J and K is latched to generate a corresponding output.

By the output generated in this way, the switching element 101g is switched on or off to control the first to third relays 102a-102c in the relay unit 102.

That is, when the periodic compression and defrosting operation characteristics of the defrost timer 100 are the same as in FIG. 6A, the relay control signal of the controller 101 is relayed during the compressor operation time and the rest period as shown in FIG. 6B. It generates a high signal to drive the, and generates a low signal to turn off the relay during the defrost time and the next rest period.

Therefore, when the control signal of the relay becomes a high signal (at the time of compressor operation timing), all of the first to third relays 102a to 102c in the relay unit 102 are connected to the contact B, and the defrost timer The micro switch in the 100 is connected to the contact A (NO).

Accordingly, since the input driving power is supplied to the first compressor 103 through the first relay 102a, the first compressor 103 is driven, and the B contact b of the second relay 102b is driven. Since there is no power supply, the second compressor 104 is turned off, and since the third relay 102c is also connected to the contact B, the second defrost heater is supplied by the power through the contact A of the micro switch. Only 106 is driven to remove frost generated in the second evaporator.

Next, if the signal output from the control unit 101 is a low signal, the micro switch is connected to the contact A (NO), the second compressor 107 by the drive power supply through the contact A (a) of the first relay 102a. ) And the micro switch is connected to the contact A (NO), so that power through the third relay 102c is supplied to the first defrost heater 105 to drive the first defrost heater 105. Defrost generated in the first evaporator is removed.

That is, the operation cycles of the first and second compressors and the first and second defrost heaters are controlled using a defrost timer having one C contact, and when the first compressor operates, the second defrost heater operates. When the second compressor operates, the first defrost heater is controlled to operate.

6 (a) and 6 (d) are operation timings of the first and second compressors, and (e) and (bar) are operation timings of the first and second defrost heaters.

As described in detail above, the present invention has the effect of preventing deduplication (the state in which two defrost heaters are driven simultaneously) by controlling the defrosting operation of two evaporators with a mechanical timer having one C contact. In addition, by alternately switching the micro switch in the mechanical timer having one C contact, it is possible to prevent fusion and deterioration of the contact that occurs when using a conventional micro switch having two C contacts, thereby preventing malfunction of the circuit. It has an effect.

In addition, since the defrost timer having one C contact is used, the manufacturing cost can be reduced compared to the defrost timer having two C contacts.

The present invention relates to the defrost of the frozen showcase, in particular to control the defrost of the two evaporators (defrost timer with one C contact) to prevent the defrost overlap and prevent fusion and deterioration of the micro switch contact The present invention relates to a defrosting device for a refrigerated showcase that reduces the overall manufacturing cost by simplifying the circuit configuration.

Claims (4)

In a refrigeration showcase in which refrigeration is performed using two compressors and two evaporators, A defrost timer (100) generating a control signal for periodically controlling the freezing and defrosting; A control unit for generating a relay control signal for selectively controlling the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106 according to the operation of the defrost timer 100; 101); A relay unit which is switched according to a control signal generated by the controller 101 to selectively drive the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106 ( Defrosting apparatus of the refrigeration showcase, characterized in that comprising a 102. The method of claim 1, The defrost timer (100) is a defrosting apparatus of a refrigeration showcase, characterized in that consisting of a motor timer for switching the micro switch having a single C contact by an external electrical signal. The method of claim 1, The controller 101 includes a transformer 101a for converting the supplied power to an arbitrary level, a first bridge diode 101b for full-wave rectifying the secondary output voltage of the transformer 101a, and the first bridge diode. A smoothing capacitor C1 for smoothing the output voltage of 101b, a constant voltage section 101c for making the DC voltage smoothed in the smoothing capacitor C1 to a constant voltage of a constant level (DC12V), and the defrost timer 100 Light is generated according to the output voltage of the second bridge diode 101d for full-wave rectifying the B contact NC output voltage of the internal micro switch and the primary output voltage of the transformer 101a, and the output voltage of the second bridge diode 101d. The photocoupler 101e which generates the generated light again as an electrical signal, and the signal generated by the photocoupler 101e as a clock and receive the signal output from the constant voltage unit 101c as a set terminal. Generating relay control signal It is switched on / off by a voltage divided by the JK flip-flop 101f, the resistors R4 and R5 for dividing the signal output from the JK flip-flop 101f, and the resistors R4 and R5. Defrosting apparatus of a refrigeration showcase, characterized in that consisting of a switching element (101g) for simultaneously controlling a plurality of relays in the relay unit (102). The method of claim 1, The relay unit 102 is switched on / off according to a control signal output from the control unit 101 to switch the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106. First to third relays 102a to selectively drive the first and second compressors 103 and 104 and the first and second defrost heaters 105 and 106 by selectively supplying and cutting off driving power. Defrost apparatus of the refrigeration showcase, characterized in that consisting of 102c).