TWI727296B - Dehumidifier capable of avoiding frost on evaporator - Google Patents

Abstract

A dehumidifier capable of avoiding frosting of the evaporator, in which an electronic expansion valve is arranged between the compressor and the evaporator, and a temperature sensor is arranged on the evaporator to sense the temperature of the evaporator and transmit a first sensor The measurement signal is sent to one of the controllers, and one of the temperature and humidity sensors detects the temperature and humidity of the environment and sends a second sensing signal to the controller; the controller estimates a value of the evaporator according to the first sensing signal Piping temperature, and estimate a dew point temperature based on the second sensing signal, and control the opening of the electronic expansion valve corresponding to a difference between the piping temperature and the dew point temperature, so that the high temperature and high pressure refrigerant output by the electronic expansion valve and the throttle device output The low-temperature and low-pressure refrigerant is mixed and fed into the evaporator, so that the pipe temperature is higher than 0C and lower than the dew point temperature without frosting the evaporator.

Description

Dehumidifier capable of avoiding frost on evaporator

The invention relates to a dehumidifier, in particular to a dehumidifier that can avoid frosting of the evaporator.

As shown in Fig. 1, the compressor 11 of the general dehumidifier 1 compresses a refrigerant into a high-temperature and high-pressure gaseous refrigerant, and then outputs it to a condenser 12. After cooling the high-temperature and high-pressure gaseous refrigerant through the condenser 12, it outputs a cooling medium. The high-pressure liquid refrigerant is sent to a capillary tube 13, after further cooling and depressurizing the temperature-lowering high-pressure liquid refrigerant through the capillary tube 13, the low-temperature and low-pressure liquid refrigerant is output to an evaporator 14, and when the low-temperature and low-pressure liquid refrigerant enters the evaporator 14, the When the surface temperature of the evaporator 14 is below the dew point temperature (the temperature at which water vapor in the air condenses), the low-temperature and low-pressure liquid refrigerant will absorb heat and evaporate from the air contacting and passing through the outer surface of the evaporator 14, so that it contacts the evaporator. The water-containing air in 14 is cooled to below the dew point temperature and condenses on the evaporator 14 and flows to a water collector (not shown), and then the cooled low-temperature and low-pressure gaseous refrigerant returns to the compressor to start the next cycle. In this way, achieve the effect of dehumidification.

However, when the dehumidifier 1 is used in a low temperature environment, such as 10°C or below, when moisture condenses on the surface of the evaporator 14, the surface of the evaporator 14 will be affected by the internal refrigerant. The temperature is too low and the rapid cooling causes the condensed water to freeze and freeze on the surface of the evaporator 14, causing the surface of the evaporator 14 to form frost, causing the surface of the evaporator 13 to be isolated from the air and unable to perform dehumidification.

Therefore, in order to solve the above problem, as shown in FIG. 2, a conventional dehumidifier 2 is provided with a two-way valve 15 between the compressor 11 and the evaporator 14. When a controller 16 in the dehumidifier 1 determines When the surface of the evaporator 14 is frosted, the controller 16 controls the two-way valve 15 to open so that the high-temperature and high-pressure gas refrigerant compressed by the compressor 11 is mixed with the low-temperature and low-pressure liquid refrigerant output by the capillary 13 and then input to the evaporator 14 to make The surface temperature of the evaporator 14 is increased to defrost, and after the defrost is completed, the controller 16 controls the two-way valve 15 to close to stop the output of high temperature and high pressure gaseous refrigerant. However, this method can only wait until the evaporator 14 is frosted before defrosting, and cannot avoid the frosting of the evaporator 14, so the dehumidification capacity cannot be increased in a low temperature environment.

Therefore, the object of the present invention is to provide a dehumidifier that can avoid frosting of the evaporator, which can increase the dehumidification capacity and increase the temperature range of its use in a low temperature environment.

Therefore, a dehumidifier capable of avoiding frosting of the evaporator of the present invention includes: a compressor; a condenser connected to the compressor to cool down the compressed high-temperature and high-pressure gaseous refrigerant output by the compressor; Throttle device, which is connected with the condenser to depressurize and output the cooled high-pressure liquid refrigerant output from the condenser Low-temperature and low-pressure liquid refrigerant; an evaporator connected with the throttling device to receive the low-temperature and low-pressure liquid refrigerant output by the throttling device; and the evaporator is connected with the compressor to turn it into a low temperature due to heat absorption The low-pressure gaseous refrigerant is output to the compressor; an electronic expansion valve is arranged between the compressor and the evaporator to control the flow rate of the compressed high-temperature and high-pressure gaseous refrigerant input into the evaporator by the compressor; a controller , Electrically connected to the electronic expansion valve to control the opening of the electronic expansion valve; a temperature sensor, electrically connected to the controller and set in the evaporator, to detect the temperature of the evaporator and generate accordingly A first sensing signal, and transmitting the first sensing signal to the controller; a temperature and humidity sensor, which is electrically connected to the controller, and detects the temperature and humidity of the environment to generate a second Sensing signal, and transmitting the second sensing signal to the controller; wherein, the controller estimates a piping temperature of the evaporator according to the first sensing signal, and estimates the current one based on the second sensing signal Dew point temperature, and correspondingly control the opening of the electronic expansion valve according to a difference between the piping temperature and the dew point temperature, so that the high temperature and high pressure gas refrigerant corresponding to the output of the electronic expansion valve is mixed with the low temperature and low pressure liquid refrigerant output by the throttling device Then input the evaporator so that the pipe temperature is lower than the dew point temperature and does not cause the evaporator to form frost.

In some embodiments of the present invention, the dehumidifier capable of avoiding frosting of the evaporator further includes a first three-way joint and a second three-way joint, and the three joints of the first three-way joint are correspondingly connected to the An output end of the compressor, an input end of the condenser, and an input end of the electronic expansion valve. The three joints of the second three-way joint are correspondingly connected to the An output end of the throttling device, an output end of the electronic expansion valve and an input end of the evaporator.

In some embodiments of the present invention, when the controller determines that the temperature of the pipe is lower than 0° C., the controller controls the opening of the electronic expansion valve to be the largest for a preset time.

In some embodiments of the present invention, the controller controls the opening of the electronic expansion valve so that the difference between the pipe temperature and the dew point temperature is between 0°C and 1°C to avoid the The evaporator is frosted.

In some embodiments of the present invention, the throttling device is a capillary tube.

The effect of the present invention is to obtain the first sensing signal returned by the temperature sensor on the evaporator at any time by the controller, and obtain the temperature and humidity sensor to detect the environmental temperature and humidity and return The second sensing signal is transmitted, and the piping temperature corresponding to the first sensing signal and the dew point temperature corresponding to the second sensing signal are correspondingly controlled to control the opening of the electronic expansion valve so that the electronic The expansion valve timely outputs an appropriate amount of high temperature and high pressure gaseous refrigerant mixed with the low temperature and low pressure liquid refrigerant output by the throttling device and then enters the evaporator, so that the piping temperature of the evaporator can be lower than the dew point temperature and higher than 0°C. It does not cause the evaporator to form frost, and expands the use temperature range of the dehumidifier of the present invention.

3: Dehumidifier

31: Compressor

32: Condenser

33: Throttle device

34: Evaporator

35: Electronic expansion valve

36: Controller

37: temperature sensor

38: Temperature and humidity sensor

41: The first three-way joint

42: The second three-way joint

The other features and effects of the present invention will be described with reference to the implementation of the drawings The formula clearly shows that: Figure 1 is a block diagram of the main components of a conventional dehumidifier; Figure 2 is a block diagram of the main components of a conventional dehumidifier with defrosting function; and Figure 3 is a block diagram of the main components of a conventional dehumidifier. A block diagram of main components of an embodiment of a dehumidifier with frosted evaporator.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same numbers.

Refer to FIG. 3, which is a block diagram of the main components (elements) of an embodiment of the dehumidifier (hereinafter referred to as the dehumidifier 3) capable of avoiding frosting of the evaporator of the present invention, which mainly includes a compressor 31 and a condenser 32 , Throttling device 33, an evaporator 34, an electronic expansion valve 35, a controller 36, a temperature sensor 37 and a temperature and humidity sensor 38. The compressor 31 receives a refrigerant and compresses the refrigerant into a high temperature and high pressure gaseous refrigerant. And in Fig. 3, the flow direction of the refrigerant is indicated by a thick arrow. The condenser 32 is connected to the output end of the compressor 31 to cool the compressed high-temperature and high-pressure gaseous refrigerant output from the compressor 31. The condenser 32 is composed of a heat exchanger with a large surface area to contact the surrounding air. Therefore, the high-temperature and high-pressure gaseous refrigerant entering the condenser 32 will release part of its heat into the air and condense into liquid, and the cooled high-pressure liquid refrigerant will be output from the condenser 32.

The throttling device 33 is connected to the condenser 32 to further reduce the pressure of the temperature-lowering high-pressure liquid refrigerant output by the condenser 32 and output low-temperature and low-pressure liquid refrigerant; the throttling device 33 may be, but not limited to, a pore or a capillary tube Or a thermostatic expansion valve, which forces the cooling and high-pressure liquid refrigerant to expand and depressurize and output the low-temperature and low-pressure liquid refrigerant. The input end of the evaporator 34 is connected with the output end of the throttling device 33 to receive the low-temperature and low-pressure liquid refrigerant output by the throttling device 33, and like the condenser 32, the evaporator 34 is supplied with moisture The large surface area through which the air passes, which is generally a pipe with a certain length (piping), such as a copper pipe and bent into a continuous S shape (snake shape), or the pipe can also be flat to provide more surface area; When the low-temperature and low-pressure liquid refrigerant enters the evaporator 34 so that the surface temperature of the evaporator 34 is below the dew point temperature (the temperature at which moisture in the air is condensed), the low-temperature and low-pressure liquid refrigerant will self-contact and pass through the outside of the evaporator 14. The surface air absorbs heat and evaporates, so that the water-containing air in contact with the evaporator 14 is cooled to below the dew point temperature, condenses on the evaporator 34, and flows to a water trap (not shown) to achieve dehumidification The role of. And the output end of the evaporator 34 is connected with the input end of the compressor 31 to output the low-temperature and low-pressure gaseous refrigerant due to heat absorption and evaporation to the compressor 31 for the next cycle.

The electronic expansion valve 35 is arranged between the output end of the compressor 31 and the input end of the evaporator 34 to control the flow rate of the compressed high-temperature and high-pressure gaseous refrigerant that the compressor 31 inputs to the evaporator 34; specifically, In other words, this embodiment also includes a first three-way joint 41 and a second three-way joint 42. The first three-way joint 41 has three joints. And the three joints are respectively connected to the output end of the compressor 31, the input end of the condenser 32, and the input end of the electronic expansion valve 35, so that the high-temperature and high-pressure gaseous refrigerant output by the compressor 31 is input to the condenser respectively.器32 and the electronic expansion valve 35. The second three-way joint 42 has three joints, and the three joints are respectively connected to the output end of the throttling device 33, the output end of the electronic expansion valve 35, and the input end of the evaporator 34, so that the joint The refrigerant output from the flow device 33 is mixed with the refrigerant output from the electronic expansion valve 35 and then input to the evaporator 34.

The controller 36 is electrically connected to the electronic expansion valve 35 to control an opening degree of the electronic expansion valve 35 (the opening range of the output end). The temperature sensor 37 is electrically connected to the controller 36 and is arranged on the evaporator 34 (on the pipe) to detect the temperature of the evaporator 34 and generate a first sensing signal accordingly, and transmit the first sensing signal A sensing signal is given to the controller 36. The temperature and humidity sensor 38 is electrically connected to the controller 36, and is arranged in the housing (or a suitable position) of the dehumidifier 3 to detect the temperature and humidity in the environment to generate a second sensing signal accordingly, And send the second sensing signal to the controller 36.

The controller 36 estimates a pipe temperature of the evaporator 34 based on the first sensing signal, and estimates a dew point temperature of the current environment based on the second sensing signal, and based on a difference between the pipe temperature and the dew point temperature , Correspondingly control the opening degree of the electronic expansion valve 35 so that the electronic expansion valve 35 outputs a high temperature and high pressure gaseous refrigerant with a flow rate corresponding to the opening degree to the second three-way joint 42, and the throttling device 33 to output to the The low-temperature and low-pressure liquid refrigerant of the second three-way joint 42 is mixed and then input to the evaporator 34, so that the evaporator The piping temperature of the hair generator 34 is lower than the dew point temperature and higher than 0° C. without causing the evaporator 34 to form frost.

Therefore, during the operation of the dehumidifier 3 of this embodiment, the controller 36 will periodically (or irregularly) control the opening of the electronic expansion valve 35 according to the difference, so that the pipe temperature and the dew point The difference in temperature is between 0°C and 1°C. Therefore, the controller 36 controls the opening degree of the electronic expansion valve 35 according to the difference between the pipe temperature and the dew point temperature at any time, so as to control the difference between 0°C and 1°C. In a low temperature environment, when the dew point temperature is greater than 1°C, the piping temperature will be greater than 0°C to avoid frosting on the surface of the evaporator 34, and allow the evaporator 34 to perform dehumidification function, thereby enhancing the dehumidifier 3 The amount of dehumidification in a low temperature environment, and the temperature range that the dehumidifier 3 can use is wider.

Furthermore, when the temperature of the environment is lower and the piping temperature of the evaporator 34 is lower than 0°C, in order to avoid the frost of the evaporator 34, the controller 36 will control the electronic expansion valve 35 to make it The opening degree is opened to the maximum and lasts for a preset time, such as 1 hour or longer, so that the evaporator 34 can quickly defrost, and can continue to perform the dehumidification function at low temperatures, and further increase the temperature range of use.

In summary, in the above embodiment, the controller 36 obtains the first sensing signal returned by the temperature sensor provided on the evaporator 34 at any time, and obtains the temperature and humidity sensor to detect the ambient temperature. , Humidity and return the second sensing signal, and based on the pipe temperature corresponding to the first sensing signal and the second sensing signal corresponding to the The dew point temperature correspondingly controls the opening of the electronic expansion valve 35 so that the electronic expansion valve 35 timely outputs an appropriate amount of high temperature and high pressure gaseous refrigerant mixed with the low temperature and low pressure liquid refrigerant output by the throttling device 33 before being input into the evaporator 34 to The piping temperature of the evaporator 34 can be lower than the dew point temperature and higher than 0°C without frosting the evaporator 34, and the operating temperature range of the dehumidifier 2 of the present embodiment is expanded, which indeed achieves the present invention The effect and purpose of avoiding the frost of the evaporator.

However, the above are only examples of the present invention. When the scope of implementation of the present invention cannot be limited by this, all simple equivalent changes and modifications made in accordance with the scope of the patent application of the present invention and the content of the patent specification still belong to This invention patent covers the scope.

3: Dehumidifier

31: Compressor

32: Condenser

33: Throttle device

34: Evaporator

35: Electronic expansion valve

36: Controller

37: temperature sensor

38: Temperature and humidity sensor

41: The first three-way joint

42: The second three-way joint

Claims (4)

A dehumidifier capable of avoiding frosting of an evaporator includes: a compressor; a condenser connected to the compressor to cool down the compressed high-temperature and high-pressure gaseous refrigerant output by the compressor; and a throttling device, It is connected with the condenser to reduce the pressure of the cooled high-pressure liquid refrigerant output from the condenser and output low-temperature and low-pressure liquid refrigerant; an evaporator is connected with the throttling device to receive the throttling device Output low-temperature and low-pressure liquid refrigerant; and the evaporator is connected to the compressor to output the low-temperature and low-pressure gaseous refrigerant due to heat absorption to the compressor; an electronic expansion valve is arranged between the compressor and the evaporator To control the flow rate of the compressed high-temperature and high-pressure gaseous refrigerant input to the evaporator by the compressor; a controller, electrically connected to the electronic expansion valve, to control the opening of the electronic expansion valve; and a temperature sensor , Is electrically connected to the controller and installed in the evaporator to detect the temperature of the evaporator and generate a first sensing signal accordingly, and transmit the first sensing signal to the controller; a temperature and humidity sensor The sensor is electrically connected to the controller, and detects the temperature and humidity of the environment to generate a second sensing signal accordingly, and transmits the second sensing signal to the controller; wherein The controller estimates a pipe temperature of the evaporator based on the first sensing signal, estimates a current dew point temperature based on the second sensing signal, and controls the correspondingly based on a difference between the pipe temperature and the dew point temperature The opening degree of the electronic expansion valve is such that the high-temperature and high-pressure gaseous refrigerant corresponding to the output of the electronic expansion valve is mixed with the low-temperature and low-pressure liquid refrigerant output by the throttling device and then input into the evaporator, so that the pipe temperature is lower than the dew point temperature and higher than 0°C without causing the evaporator to frost. The controller controls the opening of the electronic expansion valve so that the difference between the pipe temperature and the dew point temperature is between 0°C and 1°C. The evaporator is frosted. As described in claim 1, the dehumidifier capable of avoiding the frost of the evaporator further includes a first three-way joint and a second three-way joint. The three joints of the first three-way joint are correspondingly connected to one of the compressors. The output end, an input end of the condenser and an input end of the electronic expansion valve, the three joints of the second three-way joint are correspondingly connected to an output end of the throttling device, an output end of the electronic expansion valve and An input end of the evaporator. The dehumidifier capable of avoiding frosting of the evaporator according to claim 1 or 2, wherein the controller determines that the temperature of the pipe is lower than 0° C., controls the opening of the electronic expansion valve to the maximum for a preset time. The dehumidifier capable of avoiding the frost of the evaporator as described in claim 1 or 2, wherein the throttling device is a capillary tube.

Images