Defrosting control circuit and refrigeration device

Abstract

The utility model provides a defrosting control circuit and refrigeration plant, including first control loop, second control loop, third control loop and temperature relay, the first control loop is electrified to control the defroster to get electricity to defrost, and the third control loop is electrified synchronously to control the temperature relay to control the defroster to get electricity to defrost. The second control loop controls power supply of the first control loop according to the delay time of the first time relay so as to control starting of defrosting, and the third control loop controls ending of defrosting and resetting of the system according to the delay time of the second time relay so as to realize automatic defrosting control with periodic starting and fixed single starting time. The temperature relay and the eighth switch control starting of automatic defrosting. According to the defrosting control circuit and the refrigeration device, timing defrosting control can be periodically carried out, automatic defrosting can be started only when the temperature is lower than the set temperature and the defrosting requirement is met, automatic defrosting can be accurately achieved, the defrosting efficiency is guaranteed, and the working efficiency of the refrigeration device is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of refrigeration defrosting, and particularly relates to a defrosting control circuit and a refrigeration device. Background Art

[0002] During the long-term use of a refrigeration device, moisture in its working environment will frost on the surfaces of heat exchangers, ventilation ducts, etc. When the frost accumulates to a certain extent, it will reduce the working efficiency of the heat exchanger, hinder the air circulation, resulting in a decline in the refrigeration effect of the cold storage, an increase in power consumption, and may cause overload protection of the compressor or even damage the compressor. Therefore, when the frost in the cold storage reaches a certain level, defrosting treatment must be carried out.

[0003] In the prior art, the refrigeration device judges manually whether the current refrigeration device needs to start defrosting heating. When defrosting is required, after starting the defrosting function and running for a certain period of time each time, it will stop automatically. This operation method has a relatively high labor cost, and it is easy to have problems such as excessive frosting of the heat exchanger due to untimely defrosting, affecting the heat exchange effect, blocking the heat exchanger, etc., or defrosting too frequently, affecting the refrigeration effect and increasing the energy consumption of the unit. Content of the Utility Model

[0004] Based on this, the purpose of the utility model is to provide a defrosting control circuit and a refrigeration device to solve the problem of insufficient defrosting efficiency and effect in manual defrosting in the prior art.

[0005] On the one hand, the utility model provides a defrosting control circuit, including:

[0006] A first control loop, including a first switch and a driving relay connected in series in sequence between the driving positive terminal and the driving negative terminal of the first control loop. A set of normally open contact switches of the driving relay are connected in series in the energizing path of the defroster, and the driving negative terminal is connected to the power supply negative terminal;

[0007] A second control loop, including a second switch, a third switch and a first time relay connected in series in sequence between the power supply positive terminal and the power supply negative terminal. A fourth switch is connected between the middle node of the second switch and the third switch and the driving positive terminal, and the fourth switch is a normally open contact of the first time relay;

[0008] A third control loop, including a second time relay connected in parallel with the first control loop, wherein the first switch and the third switch are respectively two sets of normally closed contact switches of the second time relay;

[0009] A temperature relay, the temperature relay is connected in series with a power supply, and an eighth switch is connected in series between the positive power supply terminal and the positive terminal of the power supply. The eighth switch is a contact switch that is set to a closed state when the current temperature of the temperature relay is lower than a first set temperature.

[0010] Optionally, it further includes: a fourth control loop, the fourth control loop includes a fifth switch connected in series between the positive power supply terminal and the positive drive terminal. The fifth switch is also connected in parallel with a sixth switch. The sixth switch is another normally open contact switch of the drive relay, and the fifth switch is a self-resetting switch.

[0011] Optionally, the fourth control loop further includes a seventh switch. The seventh switch is connected in series between the positive power supply terminal and the fifth switch, and the seventh switch and the second switch also form a single-pole double-throw switch structure.

[0012] Optionally, it further includes: an operation indicator light, and the operation indicator light is connected in parallel with the first control loop.

[0013] Optionally, it further includes: a ninth switch and an alarm connected in series between the positive power supply terminal and the negative power supply terminal. The ninth switch is a contact switch that is set to a closed state when the current temperature of the temperature relay is higher than a second set temperature.

[0014] The present utility model also provides a refrigeration device, which includes the above-mentioned defrost control circuit.

[0015] The defrost control circuit provided by the present utility model includes a first control loop, a second control loop, a third control loop and a temperature relay. When the first control loop is powered on, it controls the defroster to be powered on for defrosting, and at the same time the third control loop is powered on synchronously. When the second control loop is powered on, after a first time relay delays, it controls the fourth switch to close, provides power supply for the first control loop, and starts defrosting. After the second time relay delays again, the second time relay drives the first switch and the third switch to disconnect, and the first control loop, the second control loop and the third control loop lose power synchronously, and then the first switch and the third switch are restored, and the system resets. Thus, it can realize periodic defrosting start according to the delay time of the first time relay, and automatic defrost control of the single defrost time according to the delay time of the second time relay. Among them, the temperature relay is connected in series with the power supply, and an eighth switch is connected in series between the positive power supply terminal and the positive terminal of the power supply. When the current temperature is lower than the first set temperature, the temperature relay controls the eighth switch to close, and starts the above-mentioned automatic defrosting, which can avoid frequent automatic defrosting when the temperature is relatively high and there is no obvious defrosting requirement, thereby improving the accuracy of automatic defrosting, ensuring the defrosting efficiency, and further improving the working efficiency of the refrigeration device.

[0016] The refrigeration device provided by the present utility model can enable automatic defrosting control when defrosting is required, ensure the accuracy of defrosting, ensure the defrosting efficiency, and thus improve the working efficiency of the refrigeration device. Brief Description of the Drawings

[0017] Figure 1 It is a schematic circuit diagram of the defrosting control circuit in the present utility model.

[0018] The following specific embodiments will further illustrate the present utility model in conjunction with the above-mentioned drawings. Specific Embodiments

[0019] For the convenience of understanding the present utility model, the present utility model will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present utility model are given in the drawings. However, the present utility model can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present utility model more thorough and comprehensive.

[0020] It should be noted that when an element is referred to as being "fixedly provided on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present utility model belongs. The terms used in the description of the present utility model herein are only for the purpose of describing specific embodiments and are not intended to limit the present utility model. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0022] To solve the problem of insufficient defrosting efficiency and effect in manual defrosting control in the prior art, the utility model provides a defrosting control circuit, which includes a first control loop, a second control loop, a third control loop and a temperature relay. Among them, when the first control loop is powered on, it controls the defrosting device to be powered on for defrosting, and at the same time the third control loop is powered on synchronously. When the second control loop is powered on, after the first time relay delays, it controls the fourth switch to close, provides power supply for the first control loop, and starts defrosting. After the second time relay delays again, the second time relay drives the first switch and the third switch to open, and the first control loop, the second control loop and the third control loop lose power synchronously. Then the first switch and the third switch are restored, and the system resets. Thus, it can realize periodic defrosting start according to the delay time of the first time relay, and automatic defrosting control of the single defrosting time according to the delay time of the second time relay. Among them, the temperature relay is connected in series with the power supply, and an eighth switch is connected in series between the positive power supply terminal and the positive terminal of the power supply. When the current temperature is lower than the first set temperature, the temperature relay controls the eighth switch to close, and starts the above automatic defrosting, which can avoid frequent automatic defrosting when the temperature is relatively high and there is no obvious defrosting requirement, thereby improving the accuracy of automatic defrosting, ensuring the defrosting efficiency, and further improving the working efficiency of the refrigeration device.

[0023] Specifically, as Figure 1 shown, the first control loop includes a first switch KT2-1 and a driving relay KM that are sequentially connected in series between the driving positive terminal and the driving negative terminal of the first control loop. A set of normally open contact switches of the driving relay KM are connected in series in the power-on path of the defrosting device. The driving negative terminal is connected to the power supply negative terminal. When the driving relay KM is powered on, the defrosting device is powered on and works for defrosting. Among them, defrosting can adopt methods such as hot gas bypass defrosting, electric defrosting and reverse cycle defrosting, and the defrosting device can be adaptively selected according to the specific defrosting method.

[0024] The second control loop includes a second switch SA2, a third switch KT2-2 and a first time relay KT1 that are sequentially connected in series between the power supply positive terminal and the power supply negative terminal. A fourth switch KT1-1 is connected between the middle node of the second switch SA2 and the third switch KT2-2 and the driving positive terminal. The fourth switch KT1-1 is a normally open contact of the first time relay KT1. The second switch SA2 is used as an automatic defrosting mode selection switch. After the second switch SA2 is closed, after the first time relay KT1 delays for the first delay time, such as 12 hours, it triggers and closes the fourth switch KT1-1, and the first control loop is powered on to start defrosting.

[0025] The third control loop includes a second time relay KT2 connected in parallel with the first control loop. Here, the first switch KT2-1 and the third switch KT2-2 are respectively two normally closed contact switches of the second time relay KT2. When the first control loop is powered on, the third control loop is powered on simultaneously. After the second time relay KT2 passes the second delay time, for example, 20 minutes, it disconnects the first switch KT2-1 and the third switch KT2-2. The driving relay KM of the first control loop and the first time relay KT1 of the second control loop lose power, and the defrosting ends. At the same time, the fourth switch KT1-1 returns to the open state due to the power loss of the first time relay KT1, and the second time relay KT2 of the third control loop loses power, causing the first switch KT2-1 and the third switch KT2-2 to return to the closed state again. The first time relay KT1 is powered on again and resumes timing. This cycle is repeated to achieve automatic defrosting. The specific times of the first delay time and the second delay time are not limited to the above examples and can be flexibly set according to specific defrosting requirements.

[0026] The temperature relay K is connected in series with the power supply. An eighth switch K-1 is connected in series between the positive power supply terminal and the positive end of the power supply. The eighth switch K-1 is a contact switch that is set to the closed state by the temperature relay K when the current temperature is lower than the first set temperature. The first set temperature is, for example, 2 degrees Celsius. When the temperature is lower than 2 degrees Celsius, it is determined that there is a risk of frosting, and the eighth switch K-1 is driven to close. When the first switch SA2 is closed by the user's selection and is in the automatic defrosting mode, the defrosting control can be automatically started.

[0027] Here, the eighth switch K-1 is, for example, a normally closed contact switch. The temperature relay K is selected to trigger an action when the temperature exceeds the first set temperature. When the temperature relay K fails, it can remain in the closed state to maintain the availability of other control loops. The power supply is generally an AC power supply. According to the actual situation, it can also be a DC power supply, etc.

[0028] To improve the operability of the defrosting control, in this embodiment, a fourth control loop is also included. The fourth control loop includes a fifth switch SA3 connected in series between the positive power supply terminal and the positive driving terminal. The fifth switch SA3 is also connected in parallel with a sixth switch KM1. The sixth switch KM1 is another normally open contact switch of the driving relay KM. The fifth switch SA3 is a self-resetting switch. When the second switch S2 is not closed, by triggering the fifth switch SA3, the fourth control loop provides power to the first control loop. The driving relay KM is powered on, and the sixth switch KM1 closes to maintain the powered-on state of the first control loop and keep the defrosting in progress. After passing the second delay time, the second time relay KT2 operates, and the defrosting ends, completing a single manual defrosting.

[0029] To ensure the singularity of control for manual control and automatic control, in this embodiment, the fourth control loop further includes a seventh switch SA1. The seventh switch SA1 is connected in series between the positive power supply terminal and the fifth switch SA3. The seventh switch SA1 and the second switch SA2 also form a single-pole double-throw switch structure to ensure that only one of the seventh switch SA1 and the second switch SA2 is closed at the same time, and only one of manual control and automatic control operates, avoiding repeated triggering of defrosting when manual defrosting and automatic defrosting are enabled simultaneously, resulting in overly frequent defrosting and reducing the refrigeration efficiency.

[0030] To achieve the observability of defrosting, in this embodiment, it further includes an operating indicator light L1. The operating indicator light L1 is connected in parallel with the first control loop. When the first control loop is powered on and during the defrosting execution process, the operating indicator light L1 is constantly on.

[0031] To achieve the monitoring of the refrigeration effect of the refrigeration device, in this embodiment, it further includes a ninth switch K-2 and an alarm L2 connected in series between the positive power supply terminal and the negative power supply terminal. The ninth switch K-2 is a contact switch that is set to the closed state by the temperature relay K when the current temperature is higher than the second set temperature. When the current temperature is higher than the second set temperature, it can be determined that the refrigeration effect is insufficient. The ninth switch K-2 is closed, and the alarm L2 is powered on to issue an alarm. The alarm L2 may specifically include an indicator light, a siren, etc. The second set temperature and the first set temperature may be the same or different, and are specifically set according to specific circumstances.

[0032] The defrosting control circuit provided by the present utility model can effectively achieve the timed and quantitative control of defrosting, providing an effective solution for the automatic defrosting control of the refrigeration device, ensuring the accuracy of defrosting, ensuring the defrosting efficiency, and further improving the working efficiency of the refrigeration device using this defrosting control circuit.

[0033] The present utility model also provides a refrigeration device with the above-mentioned defrosting control circuit, which can achieve timed and quantitative automatic defrosting control, ensure the accuracy of defrosting, ensure the defrosting efficiency, and improve the working efficiency of the refrigeration device.

[0034] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0035] The above-described embodiments merely represent several specific implementation manners of the present utility model. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several variations and improvements can still be made, and these all fall within the protection scope of the present utility model. Therefore, the protection scope of the patent of the present utility model shall be subject to the appended claims.

Claims

1. A defrost control circuit, characterized in that: include: The first control loop comprises a first switch and a driving relay which are sequentially connected in series between the driving positive terminal and the driving negative terminal of the first control loop, a group of normally open contact switches of the driving relay are connected in series in the power path of the defrost device, and the driving negative terminal is connected to the negative power supply terminal; The second control loop includes a second switch, a third switch and a first time relay connected in series from the positive power supply end to the negative power supply end, a fourth switch is connected between the intermediate node between the second switch and the third switch and the positive drive end, and the fourth switch is a normally open contact of the first time relay; A third control loop includes a second time relay connected in parallel with the first control loop, wherein the first switch and the third switch are two groups of normally closed contact switches of the second time relay respectively; A temperature relay is connected in series with a power supply, and an eighth switch is connected in series between the positive end of the power supply and the positive end of the power supply. The eighth switch is a contact switch of the temperature relay which is set to a closed state when the current temperature is lower than the first set temperature.

2. The defrost control circuit according to claim 1, characterized in that: Also includes: The fourth control loop includes a fifth switch connected in series between the positive power supply terminal and the positive drive terminal, the fifth switch is also connected in parallel with the sixth switch, the sixth switch is another set of normally open contact switches of the drive relay, and the fifth switch is a self-resetting switch.

3. The defrost control circuit according to claim 2, characterized in that: The fourth control loop further includes a seventh switch, which is connected in series between the positive power supply terminal and the fifth switch, and the seventh switch and the second switch also form a single-pole double-throw switch structure.

4. The defrost control circuit according to claim 1, characterized in that: Also includes: An operating indicator light is connected in parallel with the first control loop.

5. The defrost control circuit according to claim 1, characterized in that: Also includes: A ninth switch and an alarm are connected in series between the positive end and the negative end of the power supply, wherein the ninth switch is a contact switch of the temperature relay which is set to a closed state when the current temperature is higher than the second set temperature.

6. A refrigeration device, characterized in that: It comprises the defrost control circuit as claimed in any one of claims 1 to 5.

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