KR20190111614A - Method for controlling water purifying apparatus - Google Patents

Abstract

According to an embodiment of the present invention, a method for controlling a water purifier comprises the following steps of: sensing cooling water temperature in a temperature sensor and transferring sensed temperature information to a control unit; driving a compressor and a stirring member when it is determined that the cooling water temperature reaches the maximum temperature; and sensing a rotational speed of the stirring member and transferring sensed rotational speed information to the control unit. The control unit enables the compressor to be stopped when deceleration of the stirring member is sensed.

Description

Method for controlling water purifying apparatus

The present invention relates to a control method of a water purifier.

Water purifiers are devices that filter harmful substances such as foreign substances or heavy metals in water by physical and / or chemical methods.

The following prior art discloses a structure for a direct water purifier.

The direct water purifier means a water purifier in which a water tank is not required separately, and when a water supply button is pressed, water supplied through a faucet is cooled to a set temperature while being passed through a cooling unit and is directly supplied to a consumer.

In the case of a direct type water purifier, since there is no need for a reservoir, foreign matters accumulate on the bottom of the reservoir and there is no problem that bacteria grow in the reservoir.

The cooling unit of the direct type water purifier includes, as disclosed in the prior art, a cooling water tank in which cooling water is stored, an evaporator disposed above the cooling water tank, a cold water pipe disposed below the cooling water tank, and a cooling water tank. It includes a stirring member for circulating the water inside, and the heat exchanged drinking water and cooling water flowing along the cold water pipe.

In detail, the upper cooling water cooled by the evaporator flows downward toward the cold water pipe by the rotation of the stirring member, and the cold water in the cold water pipe accommodation space flows upward toward the evaporator.

In addition, when ice mass is formed on the surface of the evaporator and cold air is accumulated, heat exchange is performed not only by sensible heat but also by latent heat, so that the drinking water passing through the cold water pipe can be cooled in a short time, which is very advantageous for the direct type water purifier.

A direct type water purifier constituting such a structure and a control method thereof are disclosed in the following prior art.

According to the prior art presented, by measuring the external temperature of the water purifier and the cooling water temperature around the cold water pipe, and appropriately adjusting the amount of rotation of the stirring member based on the measured temperature value, the appropriate amount of ice is generated and maintained on the surface of the evaporator Characterized in that.

However, according to the stirrer drive control method proposed in the prior art, there are the following problems.

That is, when the temperature sensor mounted in the cooling water tank does not operate normally due to a failure, the ice may be excessively generated to hinder the operation of the stirring member, and there is a disadvantage that there is no additional preventive measure for preventing such an over ice phenomenon.

In addition, in the prior art, two temperature sensors must be installed in the cooling water tank, and a temperature sensor for measuring an external temperature must be additionally provided, thereby increasing the manufacturing cost.

Korean Patent Publication No. 2015-0019118 (February 25, 2015)

The present invention is proposed to improve the above problems.

Control method of a water purifier according to an embodiment of the present invention for achieving the above object, the step of detecting the coolant temperature in the temperature sensor, the sensed temperature information is transmitted to the control unit; Determining that the coolant temperature has reached an upper limit temperature, and driving the compressor and the stirring member; And detecting the rotational speed of the stirring member and transmitting the detected rotational speed information to the control unit, wherein the control unit stops the compressor at the moment when detecting the deceleration of the stirring member.

According to the control method of the water purifier according to the embodiment of the present invention constituting the above configuration has the following effects.

First, when the ice is excessively produced, by controlling the operation of the cooling cycle by detecting a change in the rotational speed of the stirring member, there is an advantage that there is no need to install additional components such as a temperature sensor to prevent overheating.

Second, even when the ice-cooling phenomenon is detected and the cooling cycle is stopped, the stirring member continues to rotate, and thus, the user can take out cold water even in the ice-making control process.

Third, the stirring member continues to rotate even in a state where the ice-cooling phenomenon is detected and the cooling cycle is stopped, thereby maintaining the temperature of the cooling water in the cooling water tank uniformly.

1 is an exploded perspective view of a cold water generating unit constituting a water purifier to which a control method according to an embodiment of the present invention is applied.
2 is a perspective view of the cold water generating unit with the heat insulation case removed.
3 is a longitudinal sectional view taken along 3-3 of FIG.
4 is a graph showing a change in rotational speed of the stirring member according to the change in the cooling water temperature.
5 is a flowchart showing a control method of a water purifier for preventing ice from overflowing according to an embodiment of the present invention.

Hereinafter, a method of controlling a water purifier according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings and a flowchart.

1 is an exploded perspective view of a cold water generating unit constituting a water purifier to which a control method according to an embodiment of the present invention is applied, FIG. 2 is a perspective view of a cold water generating unit with a heat insulation case removed, and FIG. This is a longitudinal cross section taken along 3-3.

1 to 3, the cold water generating unit 30 according to an exemplary embodiment of the present invention surrounds a coolant tank 33 filled with coolant and the coolant tank 33 to exchange heat between coolant and indoor air. A heat insulating case 31 for blocking, a drain valve 32 penetrating through the heat insulating case 31 to communicate with an internal space of the cooling water tank 33, and cold water piping housed in the cooling water tank 33 ( 34, a partition member 36 accommodated inside the cooling water tank 33 in a state of being positioned above the cold water pipe 34, an evaporator 35 placed above the partition member 36, and the A tank cover 37 covering an upper end of the coolant tank 33, a stirring motor 38 fixed to an inner side of the tank cover 37, and having a rotating shaft extending downward, and accommodated in the coolant tank 33. And a stirring member 39 connected to a rotating shaft of the stirring motor 38, and the thermal insulation cable. It may include a case cover 40 for covering the opened upper surface of the tooth 31.

In detail, the drain valve 32 is installed through the heat insulating case 31 and the cooling water tank 33 and is insulated from the heat insulating case 31 corresponding to a point adjacent to the bottom of the cooling water tank 33. It is inserted through the side of). When the drain valve 32 is opened, the coolant stored in the coolant tank 33 is discharged to the outside of the water purifier 10.

In addition, the heat insulation case 31 may be made of a heat insulation member such as styrofoam, and the heat insulation case 31 may be seated on the tank support 21.

In addition, the cold water pipe 34 may be wound in a spiral form to form a cylindrical shape as shown, the pipes adjacent in the vertical direction may be formed in contact with each other or spaced at a predetermined interval. In addition, the inlet end 341 and the outlet end 342 of the cold water pipe 34 may extend vertically toward the case cover 40. In addition, the inlet end 341 of the cold water pipe 34 may be connected to a water pipe connected to a water supply source, and the outlet end 342 may be connected to a water pipe connected to a outlet of the water purifier.

In addition, the partition member 36 is placed above the cold water pipe 34 so that the internal space of the cooling water tank 33 is a first space in which the evaporator 35 is accommodated, and the cold water pipe 34 is It may be partitioned into a second space that is received. Therefore, the ice formed around the evaporator 35 cannot move to the second space.

In addition, the evaporator 35 may be wound in a spiral form on the outer circumferential surface of the partition member 36. The evaporator 35 is connected to the outlet end of the expansion valve connected to the outlet end of the condenser 19. The refrigerant flowing along the refrigerant pipe forming the evaporator 35 exchanges heat with the cooling water stored in the cooling water tank 33 to cool the cooling water. The cooling water exchanges heat with the drinking water flowing along the cold water pipe 34 to cool the drinking water to a predetermined temperature.

The cooling water may freeze on the surface of the evaporator 35 to grow into ice chunks of a predetermined size. In other words, the cold air discharged from the evaporator freezes the cooling water, thereby accumulating cold air, that is, latent heat of melting. That is, even when the compressor 18 is not driven, the iced coolant and the liquid coolant exchange heat by the stirring operation of the stirring member 39, so that the coolant in the liquid state is kept below the reference temperature. You can do that.

The water purifier according to the embodiment of the present invention may be defined as an ice storage type water purifier because it accumulates latent heat by allowing a part of the cooling water to exist on the surface of the evaporator in the form of ice. In the case of the ice-cold water purifier, since the latent heat as well as the sensible heat may be used for heat exchange, the cold water discharge performance is much better than that of the iceless water purifier using only the sensible heat. accumulation

In addition, the tank cover 37 is provided to cover the upper end of the cooling water tank 33, covering the upper surface of the first space. That is, the first space is defined between the tank cover 37 and the partition member 36, and the second space is defined between the partition member 36 and the bottom of the coolant tank 33. Can be. In addition, a coolant inflow port 371 may be formed at one side of the tank cover 37. The coolant inlet port 371 is connected to a water pipe connected to a water supply source, so that the coolant is supplied to and filled with the coolant tank 33.

In addition, the stirring member 39 may be located approximately at an intermediate point of the second space, but is not necessarily limited thereto. When the stirring member 39 rotates, the coolant in the second space flows to the first space and heat exchanges with ice generated on the surface of the evaporator 35 or the evaporator 35, and the coolant in the first space It flows into two spaces so that the temperature of the cooling water is kept uniform at all points inside the cooling water tank 33. Then, the cooling water cooled through the heat exchange heat exchanges with the drinking water flowing along the cold water pipe 34 to cool the drinking water below the cold water recognized temperature. Here, the cold water recognition temperature may range from 7 degrees Celsius to 8 degrees Celsius, but is not limited thereto.

The stirring member 39 may be formed in the shape of a blade or impeller extending radially from the rotation axis as shown, but is not limited to this, various shapes can be proposed.

On the other hand, the case cover 40 is fitted to the outer peripheral surface of the upper end of the heat insulating case 31 to cover the open upper surface of the heat insulating case 31 and the cooling water tank 33. In addition, a port accommodating hole 401 may be formed in the case cover 40 to allow the cooling water inflow port 371 to be exposed to the outside. In addition, a cold water pipe guide groove 402 through which the inlet end 341 and the outlet end 342 of the cold water pipe 34 pass may be formed at one edge of the case cover 40. In addition, an evaporation pipe guide hole 403 through which the pipe of the evaporator 35 passes may be formed at the other edge of the case cover 40.

In addition, a temperature sensor (not shown) for detecting a temperature of the coolant may be mounted at one side of the coolant tank 33, and the temperature sensor may include a thermistor. The temperature sensor may be placed in the first space close to the evaporator or in the second space close to the cold water pipe 34.

In one example, the temperature sensor is located at a point closer to the evaporator 35, not only detects the temperature of the cooling water, but also grows on the surface of the evaporator 35, when the temperature of the ice is in contact with the temperature sensor Can be detected until.

4 is a graph showing a change in the rotational speed of the stirring member according to the change in the cooling water temperature.

Referring to FIG. 4, when the temperature of the cooling water reaches an upper limit temperature in a so-called stabilization section without cold water extraction, a compressor (not shown) is driven to operate a cooling cycle.

In detail, the upper limit temperature of the cooling water for cooling cycle operation may be set differently according to the use conditions, and may be 0.5 ° C. as an example, but is not limited thereto.

When the cooling cycle is operated, the low-temperature, low-pressure two-phase refrigerant flowing along the evaporation pipe 35 and the cooling water stored in the cooling water tank 33 exchange heat, thereby reducing the temperature of the cooling water.

In the section where the temperature of the cooling water is maintained at the temperature of the image, since there is no ice generation, the rotational speed of the stirring member 39 hardly changes.

When the coolant temperature falls below the freezing temperature, ice is generated on the surface of the evaporator, and the size of the ice increases over time. As the size of the ice increases, the amount of cooling water decreases, and when the amount of cooling water decreases, the flow resistance of the cooling water generated when the stirring member is rotated decreases. When the flow resistance of the cooling water decreases, the rotational speed of the stirring member 39 increases. In other words, while the voltage supplied to the stirring motor 38 is kept constant, the flow resistance applied to the stirring member 39 decreases, so that the rotational speed (Hz or rpm) of the stirring member 39 increases.

On the other hand, since the evaporator 35 is wound in a spiral form, the ice formed on the surface of the evaporator 35 grows into an empty donut shape. In addition, since the stirring member 39 is disposed to penetrate the inside of the evaporator 35, when the ice grows excessively, the inner edge of the ice may contact the rotation axis of the stirring member 39.

The instant the ice touches the stirring member 39, the stirring member 39 is reduced in speed by the frictional resistance of the ice. As shown in section A of FIG. 4, when ice grows excessively and interferes with the rotation of the stirring member 39, a phenomenon in which the increasing speed suddenly decreases occurs.

As the ice continues to grow, the rotational speed of the stirring member 39 decreases rapidly, and the load of the stirring motor 38 rapidly increases. In this state, if the operation of the cooling cycle is not stopped, a phenomenon may occur in which the stirring motor is overloaded and the stirring motor is burned out.

Here, the reason why the coolant temperature detected by the temperature sensor is displayed below minus 12 ° C is for the following reason. In detail, as the ice grows, the ice comes into contact with the temperature sensor mounted on the inner circumferential surface of the cooling water tank. From that moment, the temperature detected by the temperature sensor detects the temperature of the ice in the solid state, not the temperature of the coolant in the liquid state. And, as the operating time of the cooling cycle becomes longer, not only the size of the ice generated on the surface of the evaporator increases, but the temperature of the ice also falls further below 0 ° C.

The present invention is characterized in that the ice generated around the evaporator 35 is prevented from growing excessively by controlling the cooling cycle by sensing the speed change of the stirring member 39 as shown in the section A.

5 is a flowchart illustrating a control method of a water purifier for preventing over ice according to an embodiment of the present invention.

Referring to FIG. 5, the control method of the water purifier for preventing over ice according to an embodiment of the present invention may be performed in a stabilization section without cold water extraction. This is because, if the cold water is taken out frequently, the chance of freezing occurs.

In detail, the temperature sensor provided in the cooling water tank detects the temperature of the cooling water at predetermined time intervals (S11). The sensed coolant temperature T is transmitted to a controller (not shown) of the water purifier, and the controller determines whether the detected temperature is equal to or higher than the upper limit temperature T1. The upper limit temperature T1 may be 0.5 ° C. as described above, but is not limited thereto.

And if it is determined that the cooling water temperature is higher than the upper limit temperature, the compressor and the stirring member are driven together (S13). In addition, the rotational speed R of the stirring member is periodically detected at a predetermined time interval (S14).

On the other hand, when the compressor is driven to operate the cooling cycle, the temperature of the evaporator is lowered and heat exchange between the evaporator and the coolant is performed. The temperature sensor detects the coolant temperature T and transmits it to the controller. Then, the controller determines whether the coolant temperature reaches the lower limit temperature T2 (S15), and if it is determined that the coolant temperature T reaches the lower limit temperature T2, the driving of the compressor and the stirring member is stopped. (S16). Here, the lower limit temperature T2 may be, for example, -2.5 ° C, but is not limited thereto. The upper and lower temperature values for driving and stopping the compressor can be appropriately set according to the temperature value recognized as the cooling water.

On the other hand, the control unit receives the rotational speed value from the stirring motor 38 until the coolant temperature reaches the lower limit temperature. In addition, the controller determines whether the current rotational speed R2 of the stirring member is lower than the previous speed R1 (S17).

If it is determined that the current speed is higher than the previous speed, it means that ice growth is continuing. On the other hand, if it is determined that the current speed is reduced from the previous speed, it means that the ice grows excessively and touches the stirring member, preventing the rotation of the stirring member.

Therefore, the control unit stops driving of the compressor at the moment when the speed decrease of the stirring member is sensed, and controls the stirring member to continuously rotate (S18). Here, when the stirring member is stopped together with the stop of the compressor, since the circulation of the cooling water is not made, unevenness of the cooling water temperature may be caused inside the cooling water tank. In other words, the coolant temperature near the evaporator may be low, but the coolant temperature near the cold water piping may be high.

In addition, due to heat penetration from the outside, the temperature of the inner edge of the cooling water tank may be distributed relatively lower than the central temperature of the cooling water tank. Then, although ice is not melted in the center of the coolant tank and rotation of the stirring member is not smooth, the coolant temperature detected by the temperature sensor is sensed to be higher than or equal to the lower limit temperature, so that the cooling cycle may be restarted. Then, the possibility of re-issuance of an ice-breaking phenomenon becomes high.

Therefore, the stirring member continues to rotate even when the over-icing is detected and the compressor stops, thereby maximizing the heat exchange effect by using heat penetrating from the outside and frictional heat between the stirring member and the cooling water. Then, the cooling water temperature rises rapidly, and as a result, the ice melts quickly, and the ice-melting phenomenon can be solved in a short time. In addition, if the user draws out cold water in the ice-making control process, the ice-melting time will be shorter, and the time taken to solve the ice-breaking phenomenon will be shorter.

In addition, since the cooling water temperature is uniformly maintained at all points in the cooling water tank by the rotation of the stirring member, the control unit recognizes the cooling water temperature detected by the temperature sensor as a representative value representing the whole cooling water, and thus, accurately controls the compressor and the stirring motor. Control is possible.

On the other hand, even when only the compressor is stopped and the stirring member is rotating, the temperature sensor continuously transmits the coolant temperature value to the controller, and the controller controls whether the received coolant temperature T reaches the upper limit temperature T1. It is determined whether or not (S19).

When it is determined that the coolant temperature T reaches the upper limit temperature T1, the controller causes the compressor to be restarted (S20), and periodically restarts the coolant temperature and the rotational speed of the stirring member together with restarting the compressor. Receives the ice to detect the ice.

As such, by sensing the speed change of the stirring member to perform the ice-making control, there is an advantage that there is no need to additionally install a component for preventing ice-making, including a temperature sensor.

Claims (5)

In the control method of the water purifier,
Sensing the coolant temperature by the temperature sensor and transmitting the detected temperature information to the controller;
Determining that the coolant temperature has reached an upper limit temperature, and driving the compressor and the stirring member;
Detecting the rotational speed of the stirring member and transmitting the detected rotational speed information to the controller;
The control unit, the control method of the water purifier, characterized in that for stopping the compressor at the moment when detecting the deceleration of the stirring member. The method of claim 1,
And the stirring member is controlled to continue to rotate even if the compressor is stopped. The method of claim 2,
After the compressor is stopped, if it is determined that the temperature of the cooling water detected by the temperature sensor reaches the upper limit temperature, the compressor is restarted,
The control method of the water purifier, characterized in that the process of detecting the temperature of the cooling water and the rotational speed of the stirring member is performed repeatedly. The method of claim 1,
And if it is determined that the temperature of the cooling water reaches the lower limit temperature, driving of the compressor and the stirring member is stopped. The method of claim 4, wherein
The said upper limit temperature is 0.5 degreeC,
The said minimum temperature is -2.5 degreeC, The control method of the water purifier characterized by the above-mentioned.

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