KR101025200B1 - Dryer Control System and Control Method using Drying Heater and Heating Unit for Drying Laundry Using The Same - Google Patents

Abstract

The present invention relates to a dryer control system and a control method thereof, which reduce power consumption of a drying heater for supplying high temperature dry air to a drum in a washing machine or a laundry dryer equipped with a drying function, and reduce manufacturing costs by simplifying a structure. It is about.
A method of controlling a drying heater to control a drying heater to maintain a drum internal temperature of a laundry dryer or a laundry dryer at a preset temperature includes drying a first power of a first driving power source when the drum internal temperature is lower than the preset temperature. And applying the second power of the second driving power source relatively lower than the first power to the drying heater when the drum internal temperature is higher than the preset temperature. The dry heater includes a planar heating member made of a strip metal sheet having a low thermal density.

Description

Dryer Control System and Control Method Using Drying Heater and Drying Heating Heating Unit Using the Same

The present invention relates to a dryer control system using a drying heater, and a laundry drying heating unit using the same, and a control method thereof, and more particularly to a drying heater for supplying high temperature dry air into a drum in a washing machine or laundry dryer having a drying function. The present invention relates to a dryer control system using a drying heater, a laundry drying heating unit using the same, and a control method thereof, which reduce power consumption and reduce a manufacturing cost by simplifying a structure.

In general, a washing machine is a device that removes stains, contaminants, and stains on clothes, blankets, etc. by the action of detergent and water in the washing tank using the rotational power of an electric motor. .

In general, a washing machine is classified into a pulsator type washing machine in which a washing tank is vertically mounted and a drum washing machine in which the washing tank (hereinafter, referred to as a drum) is laid down in a substantially horizontal direction.

The drum washing machine has an advantage of low water consumption, no tangling of laundry after washing, and less damage to laundry during washing.

Recently, the drum washing machine is mainly sold, and the drum washing machine is manufactured as various products having a drying function of drying the dehydrated laundry after washing, including a drying heating unit therein.

On the other hand, the laundry dryer for drying the laundry is a device for drying the laundry washed in the washing machine, including a drying heating unit for supplying a high temperature dry air for drying the laundry into the drum in which the laundry is put.

The conventional drying unit used in the washing machine and the dryer to dry laundry uses a sheath heater, a PTC heater, a nichrome wire heater or a condensing heater.

1 is a drying heating unit employing a sheath heater, which has an air inlet port and an air outlet port as shown in the drawing, and guides the introduced air into the drum, and the inside of the duct casing 2. And a blower fan 3 that is rotated by a motor to blow air, and a sheath heater 4a that heats the air introduced and introduced into the duct casing 2.

In addition, the temperature sensor 6 is mounted inside the duct casing 2 near the air outlet and the sheath heater 4a to control the temperature of the air discharged by detecting the temperature, as well as the sheath heater 4a. ) To prevent overheating.

In this case, the temperature of the heating air supplied into the drum when drying the laundry is about 90 ~ 110 ℃ to prevent damage to the cloth of the laundry, the drying heating unit 1 is the temperature of the air discharged through the air outlet Air is discharged by heating the air inside the duct casing (2) so as to maintain within 100 ℃.

The sheath heater 4a is a heating element made by inserting a coil-shaped heating wire into a metal protective tube and sealing it with magnesium oxide powder or aluminum oxide powder as an insulator. Can be used.

In addition, the sheath heater has a metal protective tube coated on the outer surface of the sheath heater, which is easier to install than a coiled nichrome wire heater, and is chemically stable according to the material selected for the protective tube, and has excellent electrical insulation. It is used.

However, since the sheath heater has a structure in which a coil-type heating wire that is a heating element is coated with a metal protective tube through an insulator, the heat exchange efficiency is lower than that of the heater structure that heats the air passing through the duct casing by the heating wire. Since the contact surface to be heat exchanged is only the surface of the metal protective tube is heated to a high temperature of up to 580 ℃ to maintain the temperature of the air discharged through the air outlet (that is, drum supply temperature) (T _D1 ) at 110 ℃.

In order to examine the characteristics of the siege heater in more detail, the drying power of the sieve heater of the laundry dryer was set to 2050W, the internal temperature of the drum 110 ℃, the drying rate of 2.5%, and the test sample was put into dry test. Similarly, temperature characteristic graphs for the heater surface temperature T _S1 and the drum supply temperature T _D1 were obtained.

As can be seen from the graph of FIG. 7C, the peak value of the surface temperature of the heater rises to about 580 ° C. at the initial stage of operation even under the condition of air flow by the blower fan 3, and then relatively to about 450 ° C. in the latter part of the drying process. It is kept at a high temperature.

Considering that the maximum heat generation temperature of the sheath heater is 750 ° C, such a temperature rise requires an insulation structure around the heater and structural constraints to maintain a certain distance even in the arrangement of internal parts. The size of the structure is increased.

In addition, since the sheath heater is an indirect heating method, as shown in FIG. 7C, when the power is applied, the temperature increase rate is low, and when the power is cut off, the cooling rate also has a low temperature response.

As a result, when a sheath heater with a slow temperature response is applied to the laundry dryer, the power ON / OFF switching cycle of the heater to maintain the drum internal temperature (T: 110 ° C) of the temperature sensor is about 60 circuits. The drying time was 3 hours and 20 minutes and the power consumption was 3,700 WH (see Table 1).

Therefore, the conventional laundry dryer employing the siege heater has to increase the drying time due to the slow temperature rise of the siege heater under the condition of maintaining the proper temperature and cooling the temperature rise repeatedly, and pays a large amount of power consumption (3,700 WH) and a high electric charge. There is a problem.

In addition, the drying heating unit 1 is a duct casing if the drive motor of the blower fan 3 is operated for a long time to cool the sheath heater 4a after drying is completed, and thus the sheath heater 4a is not sufficiently cooled. Heat transmitted through (2) may damage the drive motor of the blower fan (3), and due to the high heat of the duct casing (2), the parts around the duct casing (2) must be designed of a material having heat resistance. This causes an additional increase in the manufacturing cost of the washing machine or dryer.

In Patent No. 457582, a plurality of coil heaters for drying and heating air are divided into a first coil heater group and a second coil heater group and individually controlled, and each of the coil heaters of the first coil heater group and the second coil heater group is controlled. Since the plate is divided into the upper side and the lower side, the drying performance of the dryer can be improved even when power is supplied to only one of the first coil heater group and the second coil heater group, and a part of the heater case is intensively generated. A heater assembly of a dryer is disclosed which has the advantage of being able to prevent it.

The heater assembly uses two coil heater groups, each of which is integrally operated. The heater assembly is individually controlled using a single driving power source, and is operated simultaneously with one or two heaters according to the laundry to be dried.

In addition, U.S. Patent Nos. 4,531,017, 4,617,547, 4,675,511, 5,324,919, 5,329,098, 5,895,597, and the like disclose various techniques required when manufacturing a heater assembly using a coil-shaped high temperature heating element. .

The heater assembly using the coil heating element disclosed in the above-mentioned US Patent No. 4,617,547 is assembled with a holding element having a plurality of insulators supported at both ends of the housing, and installed a coil heating element that generates high temperature heat in the plurality of insulators. It is simple and easy to assemble the coil, the assembly is good and has a structure that can reduce the manufacturing cost.

However, when the coil heating element is used, there is an increase in manufacturing cost due to the use of a plurality of insulators, and low safety and low efficiency due to high temperature heat generation and high power consumption.

Korean Patent Laid-Open No. 2006-14485 discloses a drying apparatus using a planar heating element that uniformly drys laundry and has excellent thermal efficiency and simple structure. The drying apparatus includes a drying space accommodating a drying object, a planar heating element installed on one surface of the drying space to dry the drying object by directly heating the interior of the drying space, and the planar heating element includes a thin plate carbon heating element; It is characterized in that it comprises an electrode which is installed on one side and the other side of the carbon heating element to apply electricity to the carbon heating element, and the insulating coating on both sides of the carbon heating element.

The drying apparatus of Korean Patent Application Laid-Open No. 2006-14485 has a structure in which a planar heating element is built in a drying space and cannot be applied to a general laundry dryer or a laundry dryer.

The conventional laundry dryer detects the internal temperature of the drum and cuts off the power supply to the heater when the temperature reaches a preset temperature so that the drum internal temperature remains constant. When the temperature falls below the preset temperature, the ON / OF unit supplies power to the heater again. It is controlled by a switching method. The internal temperature of the drum may be detected and controlled by a microcomputer using a temperature sensor or by using a thermostat in which a circuit is opened and closed at a set temperature.

BACKGROUND ART Electric heaters used in conventional laundry dryers or laundry dryers or electric heaters for heating a general target object generally use a coil-type heating element having high thermal density, slow or slow temperature response, and high temperature heating. However, since the materials having the characteristics of the high temperature heating element are mostly made of an alloy including an expensive metal such as Ni, the material cost increases and power consumption is high.

Accordingly, the present invention has been made to solve the above problems, the object of the present invention is to adopt a strip-like planar heating member made of a metal thin film having a large area of heat exchange and fast heat responsiveness and low temperature as a heat generating member and Dryer control using drying heater and laundry drying heating unit that can reduce power consumption by improving heat exchange efficiency and preventing inefficient power consumption due to high temperature heat generation by optimizing power consumption To provide a system.

It is another object of the present invention to adopt a strip-shaped planar heating member of a thin metal film as a heater, and the temperature of the heater is applied by switching the level of the driving voltage for the heater in two stages according to the internal temperature of the drum by the dual drive power method. It is to provide a dryer control system and a dryer control method to block the fall below a certain temperature to control the temperature change in the drum is not large.

It is still another object of the present invention to adopt a thin film-like heat generating member that has a low temperature response and is driven at a low temperature as a heat generating member. The present invention provides a dryer control system and a dryer control method in which a driving voltage cycle is shortened, a low level driving voltage cycle is increased, and a switching period of the driving voltage is lengthened.

It is another object of the present invention to provide a plurality of thin film planar heating members having fast temperature responsiveness at low temperature, and having a heating element and controlling the number of heating elements to which a driving voltage is applied according to the internal temperature of the drum. It is to provide a dryer control system and a dryer control method using a laundry drying heating unit that blocks the falling of the furnace so that the temperature change inside the drum is not large.

According to an aspect of the present invention, the present invention provides a dryer control system for supplying heating air for drying laundry to a drum inside a laundry dryer or a drum of a laundry dryer at a predetermined temperature: a first for applying a first electric power A driving power source; A second driving power source for applying a second power relatively lower than the first power; A drying heater having a planar heating member made of a strip metal sheet having a low thermal density; A temperature sensor for detecting an internal temperature of the drum of the dryer; When the drum internal temperature is lower than the preset temperature, the first power of the first driving power source is applied to the drying heater. When the drum internal temperature is higher than the preset temperature, the second power of the second driving power source is applied to the drying heater. It provides a dryer control system comprising a control unit for controlling to apply.

In this case, the switching device may further include a switching element for selectively applying any one of the first and second driving power sources to the drying heater according to a control signal applied from the controller.

In addition, the applied voltage of the first driving power is AC 220V, the applied voltage of the second driving power is preferably AC 120V.

Further, the first power of the first driving power is set to a capacity for heating the drying heater to raise the drum internal temperature above the preset temperature, and the second power of the second driving power is the second driving power only. When the drying heater is heated, the drum internal temperature is set to a capacity which cannot be raised above the preset temperature.

In addition, the drying heater may include a plurality of unit heaters are stacked at intervals in the cylindrical housing and each of the plate-shaped base member is equipped with a planar heating member made of a thin metal plate.

In this case, it is preferable that the planar heating member is formed by corrugation.

In addition, the drying heater is a cylindrical housing; And a plate-shaped base member made of a material having thermal conductivity and electrical insulation, respectively, and formed of a metal thin plate and insulated from the plate-shaped base member, and having a planar heating member that generates heat by being supplied with power. It may include a plurality of unit heaters stacked on.

In addition, the plurality of unit heaters may further include a corrugated heat dissipation member each formed of a thermally conductive material and mounted on an upper portion of the planar heating member.

In addition, each of the plurality of unit heaters may be formed of a thermally conductive material, and may further include a plate-type thermal conductive member contacted in an insulated state between the planar heating member and the corrugated heat dissipation member.

According to another aspect of the present invention, the present invention provides a dryer control system for supplying heating air for drying laundry into a drum of a laundry dryer or a laundry dryer at a predetermined temperature, comprising: a single driving power source; A first drying heater having a planar heating member made of a strip metal sheet having a low thermal density and generating heat corresponding to a first electric power when the driving power is applied; A second drying heater having a planar heating member made of a strip metal sheet having a low thermal density and generating heat corresponding to a second power relatively higher than the first power when the driving power is applied; A temperature sensor for detecting an internal temperature of the drum of the dryer; When the drum internal temperature is lower than the preset temperature, the driving power is simultaneously applied to the first and second drying heaters, and when the drum internal temperature is higher than the preset temperature, the driving power is applied only to the first drying heater. It provides a dryer control system comprising a control unit for controlling.

According to a control signal applied from the control unit may further include a switching device for applying the driving power to the first and second drying heater at the same time or only to the first drying heater.

The first and second drying heaters are also connected in series or in parallel.

When the first and second drying heaters are connected in parallel, the first drying heater is directly connected to the driving power source and the second drying heater is connected to the driving power source through a switching element which is selectively turned on by the controller. do.

In addition, when the first and second dry heaters are connected in series, a connection point between the first dry heater and the second dry heater and one end of the second heater are connected to a driving power source through a switching element.

According to another aspect of the present invention, the present invention provides a dryer control method for supplying heating air for drying laundry into a drum of a laundry dryer or a laundry dryer at a predetermined temperature: when the operation of the dryer is started. And a planar heating member made of a strip-shaped metal sheet having a low thermal density, and a planar heating member made of a strip-shaped metal sheet having a low thermal density and a first drying heater having a heat generation corresponding to a first electric power when a driving power is applied. And supplying driving air to the drum of the dryer by simultaneously applying driving power to a second drying heater that generates heat corresponding to a second power relatively higher than the first power when the driving power is applied; Detecting an internal temperature of the drum of the dryer; When the drum internal temperature is lower than the preset temperature, the driving power is simultaneously applied to the first and second drying heaters, and when the drum internal temperature is higher than the preset temperature, the driving power is applied only to the first drying heater. It provides a dryer control method comprising the step.

In this case, the first and second drying heaters are connected in series or in parallel.

According to another aspect of the present invention, the present invention provides a dryer control method for supplying heating air for drying laundry into a drum of a laundry dryer or a laundry dryer at a predetermined temperature: heat when the operation of the dryer is started. Supplying heating air to the drum of the dryer by applying a first electric power from a first driving power source to a drying heater having a planar heating member made of a strip metal sheet having a low density; Detecting an internal temperature of the drum of the dryer; When the drum internal temperature is lower than the preset temperature, the first power of the first driving power is applied to the drying heater, and when the drum internal temperature is higher than the preset temperature, the second driving power which is relatively lower than the first power It provides a dryer control method comprising the step of applying a second power of the drying heater.

In this case, it is preferable that the applied voltage of the first drive power is AC 220V, and the applied voltage of the second drive power is AC 120V.

In addition, the first power of the first driving power source is set to a capacity for heating the drying heater to increase the drum internal temperature above the predetermined temperature, and the second power of the second driving power source is only the second driving power source. When heating the drying heater, it is preferable that the drum internal temperature is set to a capacity that cannot rise above the preset temperature.

Further, the drying heater increases the ratio of the second period during which the second power of the second driving power is applied to the first period during which the first power of the first driving power is applied as the drying time elapses. The period in which the first and second periods are repeated also increases with the drying time.

In addition, the drying heater includes a plurality of unit heaters are stacked at intervals in the cylindrical housing and each of the plate-shaped base member is mounted with a planar heating member made of a thin metal plate.

The present invention significantly reduces power consumption and line power consumption during drying by using a drying heater capable of discharging a sufficient temperature for drying laundry by heating at a low temperature by increasing heat exchange efficiency with air. This reduces the burden and prevents overloading of electrical products.

The present invention can significantly shorten the drying time of the laundry to be heated to a temperature for drying the laundry, the power consumption can be proportionally reduced due to the shortening of the drying time.

In addition, the present invention is to produce a washing machine or a laundry dryer by lowering the heat generation temperature of the drying heater so that the material of the blower fan and the duct casing member of the drying heating unit as well as the material of the peripheral parts of the drying heating unit as a synthetic resin material Cost can be reduced.

In addition, the present invention employs a thin-film planar heating element having a large temperature response and fast heat-response and heat exchange area as a heating element to increase heat exchange efficiency with air and provide air of sufficient temperature to dry laundry even at low temperature heating. The power consumption can be reduced by preventing inefficient power consumption due to high temperature heat generation and optimizing power consumption.

1 is a perspective view showing a conventional laundry drying heating unit,
2A to 2B are a perspective view, a plan view, and a cross-sectional view taken along line X-X 'of FIG. 2B, respectively, of a laundry drying dryer having an upper lid removed therein according to the present invention;
Figure 3 is an assembly process of the unit heater used in the laundry drying drying heater according to the present invention,
4a to 4d is a perspective view showing a laundry drying heating unit employing a laundry drying drying heater, respectively, according to the present invention;
5 is a schematic block diagram showing a laundry dryer control system according to a first embodiment of the present invention;
6 is a flow chart for explaining a dryer control method of the dryer control system shown in FIG.
Figure 7a is a graph showing the temperature change with time of the drying heater in the case of using the laundry drying drying heater according to the present invention and applying multi-stage level control,
7b is a graph showing a temperature change with time of a drying heater when the laundry drying dryer according to the present invention is used and the multi-level control is not applied;
Figure 7c is a graph showing the temperature change with time of the dry heater according to the prior art,
8A to 8E are graphs each of which is enlarged by sampling each time zone in the temperature change graph of FIG. 7A;
9A and 9B are schematic block diagrams illustrating a laundry dryer control system according to a second and a third embodiment of the present invention, respectively;
10 is a flowchart for explaining a dryer control method of the dryer control system shown in FIGS. 9A and 9B;
11A to 13B are exploded perspective views of a unit heater and a front view of a dry heater as first to third modified examples of the dry heater according to the present invention, respectively;
14A to 15B are a perspective view and a plan view, respectively, of a drying heater having a cylindrical structure as another modification of the drying heater according to the present invention.

When described in detail with reference to the accompanying drawings a preferred embodiment of the present invention.

In the following description, a washing machine equipped with a function of drying laundry after a washing process is defined as a laundry dryer, and an apparatus for drying only laundry separately from the washing machine is defined as a laundry dryer.

In general, the laundry dryer is assembled in such a manner that a drying heating unit is included in a circulation duct communicating with the drum inside the entire housing, and the laundry dryer is installed outside the rear of the housing to supply heating air for drying into the drum. However, in the laundry dryer, it is also possible to employ a structure in which the drying heating unit is included in the circulation duct communicating with the drum inside the entire housing.

The present invention relates to a drying heating unit and a drying heater used therein, and may be applied to the above-described laundry dryer and laundry dryer. In the following description of the embodiment, the present invention is mainly applied to an example of a laundry dryer.

A. Dry Heater

2A to 2B are a perspective view, a plan view, and a cross-sectional view taken along line X-X 'of FIG. 2B, respectively, of a laundry drying dryer having an upper cover removed according to the present invention, and FIG. 3 is a laundry dryer according to the present invention. It is an assembling process drawing of the unit heater used for a dry heater.

Drying heater 10 for a laundry dryer according to the present invention, for example, to form a plurality of channels (CH1-CH4) through which air passes through, as shown in Figure 2a, for example, a quadrangular housing 11 Many inside, for example, three plate-shaped base members 12a-12c are provided in parallel at regular intervals. Preferably, the housing 11 is made of a metal material, and the base members 12a-12c are used as a base of the heater, and have excellent thermal conductivity and excellent electrical insulation with the heater, for example, Mica. ) Can be used.

The coupling between the base member 12a-12c and the housing 11 is, for example, a preliminarily formed groove in the longitudinal direction on the inner side wall of the housing to which the protrusion and the coupling hole type snap coupling structure or the base member are coupled, and the base It can be made by a structure or a well-known coupling method, such as sliding coupling the both ends of the member to the groove, any coupling structure can be applied if the assembly is not greatly degraded.

Each of the base members 12a-12c has a plurality of coupling through holes 14 formed in a plurality of rows in the same direction as the channel direction or in the vertical direction at regular intervals, as shown in FIG. 2C. A large number of strip-shaped planar heating members 13 are formed by corrugating the upper and / or lower sides to increase the contact area with air and set the height and pitch of the corrugation in consideration of the desired resistance value. Is supported by the crimping coupling method.

The strip type planar heating member 13 has an upper planar heating member 13a located above each base member 12a-12c and a lower planar heating member 13b positioned below the base member 12a-12c, respectively. It is preferable that the side portion and the upper portion are sequentially coupled to the coupling through hole 14.

In addition, it is preferable that the upper surface heating member 13a and the lower surface heating member 13b are connected in series to increase the resistance value proportional to the length, but the upper and lower surface heating members 13a may increase in accordance with the increase in the drying capacity of the dryer. 13a, 13b) or a combination of serial and parallel connections.

In the above-described embodiment, three first to third unit heaters 15a to 15c in which the strip-shaped planar heating member 13 is coupled to the upper and lower surfaces of the three first to third base members 12a to 12c. Is provided, the number of unit heaters (15a-15c) may vary depending on the capacity of the heater. The interconnection structure of the unit heaters 15a-15c may also be composed of a series connection, a parallel connection or a combination of series and parallel connections.

The strip-shaped planar heating member 13 is preferably coated with a ceramic layer 16 so that heat is generated when electric power is applied and electrical insulation is performed between adjacent planar heating members 13.

B. Unit Heater Manufacturing Process

The manufacturing process of the unit heater 15a will be described with reference to FIG. 3.

The strip-like planar heating member 13 used in the present invention is a single element metal thin plate such as Fe, Al, Cu, iron-based (Fe-X) and iron chromium-based (Fe-Cr) metal thin plate, Fe- (14 ~) 21%) made of any one of FeCrAl alloy sheets such as Cr- (2-10%) Al.

Preferred alloying materials of the FeCrAl alloy sheet are pecaloy alloys (also known as KANTHAL ^™ wires) or Fe-20Cr-5Al-REM (rare earth metals) synthesized at a Fe-15Cr-5Al ratio (here, REM (Y, Hf, Zr) about 1%) can be used.

Among the strip-like planar heating member 13, a more preferable material is Fe-15Cr-5Al, and Fe-15Cr-5Al is formed with an Al ₂ O ₃ (alumina) insulating film on its surface when subjected to heat treatment, thereby providing high temperature corrosion resistance. There is an advantage to solve the problem of oxidation of the iron-based material inexpensively.

However, the material of the strip-shaped planar heating member 13 can be formed into a thin plate with a specific resistance value required as a characteristic of the hot wire material, and any metal or alloy material can be used as long as it is available at low cost.

The thin metal sheet is a thin film, for example, 20 ~ 500㎛ thickness to have a rapid temperature response, such a thin plate has a surface area of 10 to 20 times or more compared with other coiled heating wire having the same cross-sectional area When the heat is generated by using the same power, the heat density generated per 1 cm 2 is low, so the calorie is low, so that low temperature heat is generated in a large area, and thus is suitable as a low temperature heating material.

Therefore, since the strip-shaped planar heating member 13 employed in the present invention is made of a thin metal strip with low thermal density, relatively low temperature heating is performed compared to a relatively thick planar heating member or coil-type heating element, and heat exchange is performed in a large area. It is possible to reduce the power consumption by utilizing the characteristics having a quick temperature response.

On the other hand, in the present invention, considering the thickness and width of the thin plate under predetermined conditions such as, for example, the laundry drying capacity and drying time of the dryer and the temperature of the air supplied into the dryer drum, the length of the thin strip is suitable do. That is, when the thickness and width of the metal thin strip are determined, the resistance value per unit length is known, and thus the length of the thin strip can be determined by calculating a resistance value determined according to a desired heater capacity (that is, power consumption).

If the length of the thin strip is determined through the above calculation process, the strip 17 having a predetermined width is prepared by slitting a wide thin plate (S1). For example, when the heater capacity (that is, the power consumption) is set to 2000w as in Example 1 to be described later, and the metal sheet made of Fe-15Cr-5Al is formed into a strip having a thickness of 50 μm and a width of 5 mm, the length of the strip is It is set to about 1.2m.

In consideration of the size of the housing 11 allowed for the drying heater and the length of the strip 17, a corrugation process is performed to form a corrugation strip 18 (S2). In this case, the height h of the peak of the corrugation strip 18 and the pitch p between the valley and the valley are the number of base members 12a-12c in which the planar heating member 13 is installed in the housing 11. And considering the attachment area of the planar heating element. The shape of the corrugation may be composed of a sine wave shape, a square wave shape, or a triangle.

Thereafter, the surface of the corrugation strip 18 is coated on both sides with a ceramic powder mixed with a known binder, and then sintered so that the electrical layer can be electrically insulated with respect to the corrugation strip 18. When formed, the above strip-like planar heating member 13 is obtained (S3).

On the other hand, the base member 12a is cut in accordance with the channel width of the housing 11, the thin plate made of mica (S4), a plurality of cut to the mica thin plate 12 at 1/2 intervals of the corrugation pitch (p) When the through-hole 14 is drilled, the base member 12a is obtained (S5).

Thereafter, when the pair of planar heat generating members 13a and 13b are alternately assembled to the through holes 14 at the upper and lower portions of the base member 12a (S6), the unit heater 15a is obtained.

In this case, not only the pair of planar heating members 13a and 13b assembled to the base member 12a but also the plurality of planar heating members 13 assembled in a plurality of different rows are interconnected to be connected in series.

The plurality of unit heaters 15a-15c assembled in the above-described manner are assembled in the housing 11 as shown in FIG. 2A to form the dry heater 10. Each planar heating member 13 is connected in series or in advance. You can use a combination of serial and parallel connections to match the set power usage.

C. Drying Heating Unit

On the other hand, the drying heater 10 is installed in a laundry dryer or a laundry dryer is used included in the drying heating unit 100 for blowing dry air heated in the laundry drum.

The drying heating unit 100 includes an air inlet 102a and an air outlet 102b and a duct casing 102 for guiding the introduced air into a drum (not shown), and the duct casing 102. A blower fan 103 mounted therein and rotating by a motor 25 (M) (FIG. 5) to blow air, and a drying heater 10 mounted inside the duct casing 102 to heat air. It includes.

In addition, the temperature sensor 22 is installed near the air outlet 102b inside the duct casing 102 to detect the temperature of the air discharged to the drum and input the same to the controller 23. The temperature sensor 22 may be installed inside the drum instead of the air outlet 102b to detect the drum internal temperature.

The drying heater 10 may have a structure of the above embodiment or a structure of another embodiment to be described later.

As shown in FIGS. 4A and 4B, the drying heating unit 100 includes a duct casing 102 having a linear structure, and a drying heater 10 and a blower fan 103 are arranged in a straight line of the duct casing 102. The air is introduced by the rotation of the blower fan 103, the heated air is heated by the drying heater 10, and the dry air heated in the drum is discharged in one direction.

4C and 4D, the drying heating unit 100 of the present invention has a structure in which the duct casing 112 is bent at a right angle, and the drying heater 10 and the blower fan 103 are formed. It is disposed at both ends of the right angled bent duct casing (112).

Therefore, the drying heater 10 and the blower fan 103 are positioned to form an angle of 90 degrees, and the air is introduced by the rotation of the blower fan 103, and the inside of the drum is heated by the drying heater 10. The drying air is discharged to the furnace, but the air flow is changed by 90 degrees.

The above embodiment has a structure in which the drying heater 10 and the blower fan 103 are assembled together in one duct casing 102, but the drying heater 10 is installed separately from the blower fan 103. Can be. That is, the drying heater 10 may be installed at the air inlet of the drum, and the blower fan 103 may be installed at the air outlet of the drum.

D. Dryer Control System and Control Method

<First Embodiment>

FIG. 5 is a schematic block diagram showing a first embodiment of a laundry dryer control system according to the present invention, and FIG. 6 is a flowchart for explaining a dryer control method of the dryer control system shown in FIG.

Referring to FIG. 5, in the laundry dryer control system according to the first embodiment of the present invention, a plurality of key input units 21 for inputting a user request command and an operation on / off input through the key input unit 21 are provided. Temperature sensor 22 for detecting the drum internal temperature (T) of the laundry dryer according to the command, and the current drum interior detected from the temperature sensor 22 when the operation start command is input through the key input unit 21 The control unit CPU generates a heater control signal S _H for driving the heater _H and generates a blower motor driving signal S _M for driving the blower fan 103 based on the temperature T. : 23).

The control unit 23 stores therein a first memory (for example, a ROM) in which a control program for executing the dryer control method shown in FIG. 6 is stored, and a second data storing temporary data during processing. Microcomputers incorporating memory (e.g., RAM) or other well-known signal processing devices in which the memory device is separate from the processor may be used.

The output of the control unit CPU 23 is applied to the dry heater 10 by switching the movable contact 28a according to the logic level of the heater control signal S _H , that is, "0" and "1". The switching element 28 for switching to one of the first and second driving power sources 26 and 27, and the blower motor 25 (M) for driving the blower fan 103 in accordance with the blower motor driving signal S _M are provided. It is connected.

As the switching element 28, as shown in FIG. 5, a device such as an SCR or a triac suitable for configuring an AC power source or switching an AC power source may be used.

When the relay is used as the switching element 28, the first driving power source 26, for example, 220V AC voltage, 9.0A current is applied to the first input 28b, which is the contact B of the relay, and is the contact A. A second driving power source 27, for example, a 120V AC voltage, a current of 4.95 A is applied to the second input 28c, and the other end of the movable contact 28a is connected to the heater H 10. .

In this case, when the logic level of the heater control signal S _H provided from the control unit 23 is "0", the relay 28 receives 220V AC voltage of the first driving power supply 26 to dry the heater 10. ), And when the logic level of the heater control signal (S _H ) is "1", the 120V AC voltage of the second driving power source 27 is applied to the drying heater (10).

Referring to Figure 6 the operation of the laundry dryer according to the present invention configured as described above are as follows.

First, when a user turns on the power through the key input unit 21, power is supplied and the laundry dryer enters an operation standby state (S10).

Then, after the user selects the laundry drying condition through the key input unit 21, and presses the operation key to start the drying operation (S11), the control unit 23 recognizes the user command and blows the heater control signal (S _H ) and the blower. The motor driving signal S _{M is} supplied to the switching element 28 and the blower motor 25 to operate the drying heater 10 and the blower motor 25, and at the same time, the drum internal temperature T through the temperature sensor 22. ) (S12, S13).

In the initial state, the controller 23 generates a signal having a logic level of “0” of the heater control signal S _H and supplies it to the switching element 28. Therefore, when the relay is used as the switching element 28, the movable contact 28a is connected to the first input 28b, which is the B contact of the relay, so that the first voltage and the first current from the first drive power supply 26 That is, first power), for example, 220V AC voltage, 9.0A current is applied to the drying heater 10. That is, the electric power applied from the first drive power supply 26 to the dry heater 10 is set to about 2000W. This applied power is set similar to the power consumption used in a general laundry dryer.

In response to the application of the first voltage, the drying heater 10 is operated to generate heat, and the blower motor 25 is operated so that air introduced by the blower fan 103 is introduced into the duct casing 102 or 112 of the heating unit 100. Heat exchange in the drying heater 10 while passing through) is supplied to the drum of the laundry dryer.

In this case, when the heater shown in Fig. 2A using the strip-shaped thin film planar heating member as the dry heater 10 is applied, since the strip-shaped planar heating member 13 is made of a metal thin strip having a low thermal density, that is, The large surface area makes the temperature responsive very fast, reaching a preset reference set temperature T _R within about 20 seconds after power is applied.

Meanwhile, the controller 23 compares the drum internal temperature T detected by the temperature sensor 22 with the reference set temperature T _R (S14), so that the drum internal temperature T is the reference set temperature T _R. Less than), the drying heater 10 is continuously driven according to the first electric power.

That is, when the determination result of step S14 indicates that the drum internal temperature T is smaller than the reference set temperature T _R , the process proceeds to step S18, where the controller 23 controls the humidity of the laundry according to a well-known determination method. If it is determined that the drying of the laundry is not yet completed, the process proceeds to step S12 and continues to drive the drying heater 10 according to the first electric power.

In this case, the reference set temperature T _R is set to 100 ° C., for example.

However, as a result of comparing the drum internal temperature (T) with the reference set temperature (T _R ) (S14), when the drum internal temperature (T) is greater than the reference set temperature (T _R ), the controller 23 controls the heater control signal. A signal whose logic level of S _H is "1" is generated and supplied to the switching element 28. Accordingly, the relay used as the switching element 28 is switched to the second input 28c whose movable contact 28a is the contact A, so that the second voltage and the second current from the second driving power source 27 (i.e., 2 power), for example, a 120V AC voltage and a 4.95A current are applied to the drying heater 10 (S15). That is, the power applied to the drying heater 10 from the second drive power source 27 is set to about 595W.

In a typical laundry dryer, a single driving power source is used to drive the heater. Therefore, when the drum internal temperature T rises larger than the reference set temperature T _R , the control unit cuts off the power supply to the heater.

As described above, when the driving power source for the drying heater 10 is switched from the first voltage / first current (first power) to a relatively low second voltage / second current (second power), the drying heater 10 Since the amount of heat generated at the drum internal temperature (T) is not sufficient to maintain the reference set temperature (T _R ), the drum internal temperature (T) gradually decreases.

Thereafter, when the drum internal temperature T decreases as the drying heater 10 is driven at the second electric power, the temperature sensor 22 detects the drum internal temperature T (S16), and the controller 23. To provide.

As a result, the controller 23 compares the detected drum internal temperature T with the reference set temperature T _R (S17), so that the drum internal temperature T is larger (higher than the reference set temperature T _R ). ) And returns to step S15 to continue driving the drying heater 10 in accordance with the second electric power, and when the drum internal temperature T is lower (lower) than the reference set temperature T _R , the control unit ( 23, the process proceeds to step S18, when it is determined that the laundry is finished drying, and when it is determined that the drying is not completed, the process proceeds to a step S12 to drive the drying heater 10 according to the first electric power. That is, by switching the logic level of the heater control signal S _H to "0" and supplying it to the switching element 28, the first power is supplied from the first driving power supply 26 to the dry heater 10. As a result, the internal temperature of the drum rises again.

As described above, the control unit 23 proceeds to step S18, and if it is determined that the drying of the laundry is not completed, the drying of the laundry is continued while repeating the above-described steps (S12) to (S18). The first and second driving powers 26 and 27 are selectively applied to the drying heater 10 alternately until it is made.

In addition, when the controller 23 determines that drying of the laundry is completed in step S18, a power switch (not shown) for the first and second driving powers 26 and 27 for supplying power to the drying heater 10. By turning off), driving to the drying heater 10 is stopped, driving to the blower motor 25 is stopped, and all processing procedures related to the drying function are finished.

Although the drying control system of the laundry dryer of FIG. 5 is shown to directly control the blower motor 25 in the controller 23, the blower motor 25 may be controlled through a well-known load driving unit. In addition, it is of course possible to drive the blower fan in conjunction with the motor for driving the drum instead of the blower motor 25.

In the description of the laundry dryer control system and the dryer control method according to the first embodiment of the present invention with reference to FIG. Explained.

Hereinafter, when the drying heater according to the first embodiment of the present invention is applied to a laundry dryer, drying characteristics will be described in comparison with the conventional example.

<First Experimental Example>

In the following Experimental Example 1, the embodiment of the present invention uses a dry heater adopting a strip-shaped planar heating member made of a metal sheet according to the present invention shown in FIG. As shown in FIG. 1, the sheath heater is used to drive a single driving power source (220V).

For comparative experiments, the present invention replaces only the heater with the present invention dry heater in the laundry dryer (Model No .: WD-DR351S) of LG Electronics Co., Ltd., and applies a single driving power supply method (220V) to the driving power thereof. In the conventional example, a laundry dryer (Model No .: WD-DR351S) of LG Electronics Co., Ltd. that uses a sheath heater and a single driving power supply method (220V) is applied.

In the examples of the present invention and the prior art, the same test sample was added and the drying characteristics were measured, and the drying rate was set to 2.5%.

7A and 7C show graphs obtained by measuring heater surface temperatures T _S12 and T _S1 and drum supply temperatures T _D12 and T _{D1 in} the case of the inventive examples and the prior art, respectively. It is shown in Table 1 below summarized the drying characteristics shown in the operating conditions and measurement results.

Conventional example Inventive Example Remarks Heater type Sheath heater Strip Thin Film Planar Heating Element Drive control method 220V single drive power 220V single drive power power 2050 W 1500 W -550 W Drum internal temperature 110 ℃ 100 ℃ -10 ℃ Switching frequency 60 times 200 times +140 ON / OFF
Switching cycle 2 minutes 55 seconds / 55 seconds 35 seconds / 22 seconds Drying time 3H 20M 3H 30M + 10M Power 3720WH 3230 WH 13.1%

As shown in Table 1, the drying heater of the present invention increased the drying time by 25 minutes compared with the conventional example using the sheath heater and the single driving power source (220V) even when a single driving power source was applied as the driving power for the present invention. In addition, although the power (capacity) of the heater is reduced by (-) 550W, it can be seen that the power consumption is 13.1% smaller.

As shown in Figure 7a, the strip-shaped planar heating element heater of the present invention 200 switching occurs during the drying time of 3H 30M due to the rapid temperature response, in the conventional example using a siege heater as the siege heater as shown in Figure 7c Due to the slow temperature response of, 60 ON / OFF switching occurred during the drying time of 3H 20M.

In this case, the average temperature rise time (ON period) is about 35 seconds and the cooling time (OFF period) is 22 seconds in the heater of the present invention, but in the conventional example using a sheath heater, the temperature increase time is 2 minutes 55 seconds and cooling It is shown that the time is 55 seconds, indicating that both the temperature rising time and the cooling time are long. That is, in the heater of the present invention, the temperature rise time, that is, the time for supplying power for the temperature rise (ON period) is relatively short compared with the conventional example, it can be seen that the overall power consumption is small.

Second Experimental Example

In the second experimental example, the embodiment of the present invention uses the dry heater employing the strip-shaped planar heating member made of the thin metal plate according to the present invention shown in FIG. As in the first example, the conventional example is driven by a single drive power supply method (220V) using a sheath heater as in the first experimental example.

For comparison experiments, the present invention is applied to the drying heater and the driving power in the laundry dryer (Model No .: WD-DR351S) of LG Electronics Co., Ltd. In the conventional example, a washing dryer (Model No .: WD-DR351S) of LG Electronics Co., Ltd. that uses a sheath heater and a single driving power supply method (220V) is applied.

In the examples of the present invention and the prior art, the same test sample was added and the drying characteristics were measured, and the drying rate was set to 2.5%.

* Graphs obtained by measuring heater surface temperatures T _S11 and T _S1 and drum supply temperatures T _D11 and T _{D1 in} each of the examples of the present invention and the prior art are shown in FIGS. 7B and 7C, respectively. It is shown in Table 2 summarized the drying characteristics shown in the operating conditions and measurement results.

Conventional example Inventive Example Remarks Heater type Sheath heater Strip Thin Film Planar Heating Element Drive control method Single drive power Dual drive power power 2050 W 2000W / 595W Drum internal temperature 110 ℃ 100 ℃ -10 ℃ Switching frequency 60 times 108 times +48 Drying time 3H 20M 2H 58M -22M Power 3700 WH 2920WH 21%

As shown in Table 1, the embodiment of the present invention to which the present invention is applied to the dry heater and the driving power thereof has a drying time when compared with the conventional example using the siege heater and the single driving power source (220V). This shortened by 22 minutes, it can be seen that the power consumption is 21% smaller.

As shown in Figure 7b and 7c, the strip-shaped planar heating element heater of the present invention 108 switching occurs during the drying time of 2H 58M due to the rapid temperature response, but in the conventional example using the siege heater Due to the slow temperature response, 60 ON / OFF switching occurred during the drying time of 3H 20M.

That is, in the heater of the present invention, a difference occurs as the drying time elapses, but the average temperature rise time for raising the drum internal temperature to the set temperature by applying the first voltage / first current (first power) to the driving power is It is about 15 to 20 seconds and shortened as the period elapses, and the cooling time to which the second voltage / second current (second power) is applied is gradually increasing with time.

On the other hand, in the conventional example using a siege heater, the temperature rise time (ON period) is 2 minutes 55 seconds and the cooling time (OFF period) is 55 seconds, so that both the temperature increase time and the cooling time are long, and no significant difference occurs over time. . In this case, a long temperature rise means a long power supply time.

In addition, referring to FIGS. 7A and 8A to 8E, in the present invention, a first period T1 and a second voltage / in which a first voltage / first current (first power) is applied as a driving power source for a dry heater. The ratio of the second period T2 to which the second current (second power) is applied increases as the drying time elapses, and the period in which the first period T1 and the second period T2 repeat is also over time. It can be seen that the increase.

When the change in the heater surface temperature T _S11 is referred to, the first period T1 during which the first power is applied to the heater is shortened as time passes, and the second power relatively lower than the first power is applied. Increasing the second period T2 means that the amount of power required to maintain the set temperature is decreased as time passes.

Meanwhile, referring to FIGS. 7A to 7C, the surface heating member heater of the present invention increases the heater surface temperature T _S1 to about 155-158 ° C., but the surface temperature T _S2 of the heater of the conventional example is about It was found to rise to 580 ° C. Therefore, the sheath heater of the prior art in which the high temperature heat is generated is not easy to design a compact structure in consideration of the isolation from the peripheral elements, etc., while the heater of the present invention is less constrained and the compact structure design can be made. .

When the first and second experimental results are combined, the present invention reduces the amount of power consumption compared to the prior art using the sheath heater even when the dry heater of the present invention is replaced and the driving power thereof is applied to a single driving power source (220V). You can see that.

However, in the case of adopting a strip-shaped thin film planar heating member having a fast temperature response, that is, a short heating time and a cooling time, as a dry heater, the heater is cooled during the turn-off period of the heater (ie, the cooling period). In order to maintain the temperature between 90 and 100 ℃, it can be seen that the adoption of the dual drive power system that drives at low power (ie low voltage / low current) instead of turn-off can further reduce power consumption. .

Second Embodiment

FIG. 9A is a schematic block diagram illustrating a laundry dryer control system according to a second embodiment of the present invention. FIG. 10 is a flowchart illustrating a dryer control method of the dryer control system shown in FIG. 9A.

Referring to FIG. 9A, a dryer control system of a laundry dryer according to a second embodiment of the present invention includes a plurality of key input units 21 and a key input unit 21 for inputting user request commands similarly to the first embodiment. Temperature sensor 22 for detecting the drum internal temperature (T) of the laundry dryer according to the operation on / off command input through the) and, if the operation start command is input through the key input unit 21, the temperature sensor ( The blower fan 103 is generated while generating heater control signals for driving the first and second heaters H1 and H2 10a and 10b based on the current drum internal temperature T detected from And a control unit (CPU) 23 for generating a blower motor drive signal for driving.

The control unit 23 has a first memory (for example, a ROM) in which a control program for executing the dryer control method shown in FIG. 10 is stored, and a second data storing temporary data during processing. Microcomputers incorporating memory (e.g., RAM) or other well-known signal processing devices in which the memory device is separate from the processor may be used.

At the output of the control unit CPU 23, a switching element for simultaneously or selectively driving only one of the first and second heaters H1 and H2 according to a logic level of the heater control signal, that is, "0" and "1". A blower motor 25 (M) for driving the blower fan 103 is connected to the 24 and the blower motor driving signal.

In the first embodiment, the dual drive power system of AC 220V and AC 120V is adopted. In the second embodiment, a single drive power system (AC 220V) is used. Two first and second heaters H1 and H2 10a and 10b to simultaneously drive the first and second heaters H1 and H2 according to the drum internal temperature T. It is a method of repeating driving.

To this end, the output of the single drive power source 26 is directly connected to the first heater 10a, and is connected to the second heater 10b through a switching element 24. In this case, the output terminal of the single drive power supply 26 applies an output of the drive power supply 26 to the first heater 10a and the switching element 24 in response to the user pressing the operation key to start the drying operation. It may further include a switch (not shown).

In addition, the resistance value of the heater is set such that the power is 515W when the AC 220V voltage is applied to the first heater H1, and the power is 1405W when the AC 220V voltage is applied to the second heater H2. The resistance value of the heater is set.

In this case, when the logic level of the heater control signal provided from the controller 23 is " 1 ", the switching element 24 turns off the switching element 24 from the single drive power supply 26. When 220V AC voltage is applied to both the first and second heaters H1 and H2, and the logic level of the heater control signal is "0", the 220V AC voltage is turned off as the switching element 24 is turned off. 1 to be applied only to the heater (H1). Therefore, when 220V AC voltage is applied to both the first and second heaters H1 and H2, the power is set to 1920W. In this case, the electric power setting of the first heater H1 is set to an appropriate size to prevent the drum internal temperature T from falling sharply to 100 ° C. or lower when driven by the first heater H1 alone.

The switching element 24 may be configured using a relay, or an element such as an SCR or a triac suitable for switching an AC power source. It is also possible to configure a circuit using a thermostat instead of the switching element 24 and the temperature sensor 22.

The operation of the laundry dryer according to the present invention configured as described above will be described with reference to FIG. 10.

First, when the user powers on the power input dmf (ON) through the key input unit 21, power is supplied, and the laundry dryer enters an operation standby state (S20).

Then, after the user selects the laundry drying condition through the key input unit 21, and presses the operation key to start the drying operation (S21), the control unit 23 recognizes the user command and receives the heater control signal and the blower motor driving signal. As the switching element 24 is turned on by supplying it to the switching element 24 and the blower motor 25, respectively, the single driving power source 26 and the second heater H2 are connected to each other to form the first and second heaters. Both the H1 and H2 10a and 10b and the blower motor 25 are operated and at the same time the drum internal temperature T is received through the temperature sensor 22 (S22 and S23).

In the initial state, the controller 23 generates a signal having a logic level of "1" of the heater control signal and supplies it to the switching element 24. In this case, for example, 220 V AC voltage is applied to the switching element 24 from the driving power source 26 to both the first and second heaters H1 and H2 10a and 10b.

Therefore, the total power applied to the first and second heaters 10a and 10b is set to about 1920W. This applied power is set similar to the power consumption used in a general laundry dryer.

As 220V AC voltage is applied to both the first and second heaters 10a and 10b, heat is generated and the blower motor 25 is operated so that air introduced by the blower fan 103 is heated. Heat exchange in the first and second heaters (10a, 10b) while passing through the duct casing (102 or 112) of the) is supplied to the drum of the laundry dryer.

In this case, when the heater shown in Fig. 2A using the strip-shaped thin film planar heating member as the first and second heaters 10a and 10b is applied, the strip-shaped planar heating member 13 is a metal thin strip having low thermal density. In other words, the surface area is so large that the temperature response is very fast to reach the preset reference set temperature (T _R ) within about 20 seconds after the power is applied.

Meanwhile, the controller 23 compares the drum internal temperature T detected by the temperature sensor 22 with the reference set temperature T _R (S24), so that the drum internal temperature T is the reference set temperature T _R. If smaller than), the first and second heaters 10a and 10b are continuously driven.

That is, when the determination result of step S24 indicates that the drum internal temperature T is smaller than the reference set temperature T _R , the control unit 23 proceeds to step S28, and the controller 23 controls the humidity of the laundry according to a well-known determination method. If it is determined that the drying of the laundry is not yet completed, the process proceeds to step S22 to continue to drive the first and second heaters 10a and 10b under the same conditions.

In this case, the reference set temperature T _R is set to 100 ° C., for example.

When the first and second heaters 10a and 10b are simultaneously driven, the temperature of the drum internal temperature T increases, and when the time passes for about 20 seconds, the temperature rises above the reference set temperature T _R.

Accordingly, when the drum internal temperature T is compared with the reference set temperature T _R (S24), the drum internal temperature T becomes larger than the reference set temperature T _R. In this case, the controller 23 generates a signal having a logic level of "0" of the heater control signal and supplies it to the switching element 24. As a result, the switching element 24 is turned off so that power supply to the second heater 10b is cut off and power is supplied only to the first heater 10a (S25).

In general, the laundry dryer uses a single driving power to drive a single heater. Therefore, when the drum internal temperature (T) rises higher than the reference set temperature (T _R ), the control unit cuts off the power supply to the single heater. do.

However, in the present invention, when the drying operation is performed, the driving power is continuously supplied to the first heater 10a to maintain the heat generation state, and the second heater 10b is switched according to the drum internal temperature T. In accordance with the turn-on (ON) and turn-off (OFF) it is repeated to supply and cut off the power to the second heater (10b).

If the switching element 24 is turned off and the power is cut off from the second heater 10b, the amount of heat generated by the first heater 10a is based on the drum internal temperature T and the reference set temperature T _R. The drum internal temperature (T) is gradually lowered because it is not sufficient to maintain.

Then, when the drum internal temperature (T) falls, the temperature sensor 22 detects the drum internal temperature (T) (S26) and provides it to the controller 23.

As a result, the controller 23 compares the detected drum internal temperature T with the reference set temperature T _R (S27), so that the drum internal temperature T is larger (higher than the reference set temperature T _R ). ), The control unit 23 returns to step S25 to continuously drive only the first heater 10a, and if the drum internal temperature T is lower (lower) than the reference set temperature T _R. In step S28, when it is determined that the laundry is finished to dry and it is determined that the drying is not completed, the process proceeds to step S22 to drive both the first and second heaters 10a and 10b. That is, by switching the logic level of the heater control signal to "1" and applying it to the switching element 24, 220V AC voltage is supplied to the first and second heaters 10a and 10b. As a result, the internal temperature of the drum rises again.

As described above, the control unit 23 proceeds to step S28, and if it is determined that the drying of the laundry is not completed, the drying of the laundry is repeated while the procedure of steps S22 to S28 is repeated. Until this, the two-heater driving state for simultaneously driving the first and second heaters 10a and 10b and the one-heater driving state for selectively driving only one heater are repeatedly performed.

In addition, if it is determined in step S28 that the laundry is finished drying, the controller 23 turns off the power switch (not shown) for supplying power to the heater, thereby turning the first and second heaters 10a and 10b on. Stops the drive to the blower motor 25, and terminates all processing procedures related to the drying function.

Third Embodiment

9B is a schematic block diagram showing a laundry dryer control system according to a third embodiment of the present invention.

In the second embodiment, the first and second heaters 10a and 10b are connected in parallel, but the third embodiment differs in that the first and second heaters 10a and 10b are connected in series. .

That is, in the third embodiment, the first and second heaters 10a and 10b are connected in series between a single drive power supply (AC 220V) 26 and the ground, and the one end 31 of the second heater 10b is connected to the ground. The switching element 29 is connected to the connection point 30 between the first heater 10a and the second heater 10b to selectively connect the driving power supply 26.

Similarly to the second embodiment, the controller CPU 23 applies the heater control signal to the switching element 29 according to the internal temperature T of the drum to supply the driving power 26 to the second heater H2. The first heater H1 and the second heater H2 are driven at the same time by connecting to one end 31 of the power source, or the driving power source 26 is connected between the first heater H1 and the second heater H2. The controller 30 is connected to 30 to control only the first heater H1 to be driven.

The switching element 29 may be configured using a relay, or an element such as SCR or triac suitable for switching an AC power source.

In the dryer control system of the laundry dryer according to the third embodiment, the heater is controlled according to the dryer control method shown in FIG. 10. The dryer control method according to the third embodiment is the same as the dryer control method of the second embodiment except that the control unit CPU 23 controls the switching element 29 instead of the switching element 24. Omit.

In the present invention according to the second and third embodiments, similarly to the first embodiment, only the first period T1 and the first heater H1 in which the first and second heaters H1 and H2 are simultaneously driven are driven. When the second period T2 is compared, the length of the second period T2 increases as the drying time elapses, and the period in which the first period T1 and the second period T2 are repeated also changes over time. It appears to increase accordingly.

Meanwhile, in the above-described embodiment, three drying heaters 10 for a laundry dryer are connected to three first to third base members 12a-12c and strip-like surface heating members 13 are coupled to upper and lower surfaces. Although the structure having the first to third unit heaters 15a-15c is described by way of example, the drying heater 10 may be modified as follows.

E. Dry Heater Modifications

<First Modification>

As shown in FIG. 11A, the dry heater 104 according to the first modification is provided with a planar heating member 120 on an upper portion of the plate-shaped base member 110 in which the unit heater 105 has a flat plate shape. The plate-shaped heat dissipation member 140 is formed on the top of the planar heating member 120 is laminated.

The planar heating member 120 is processed by a thin metal plate in a zigzag pattern, and both ends are fixed by fastening screws or bolts to the upper portion of the base member 110. In addition, first and second connection members 142a and 142b are coupled to both end portions of the heat dissipation member 140, and the heat dissipation member 140 is formed through the first and second connection members 142a and 142b. Fixing is performed by fastening screws or bolts at both ends of the planar heating member 120 and the base member 110 disposed below.

The plate-shaped base member 110 is formed of an aluminum plate (110mm * 55mm), and is formed to be electrically insulated even at a voltage of 5kV by anodizing the surface to form an alumina insulating film, and also, the plate-shaped heat radiating member 140 is formed by corrugating an aluminum plate on which an anodized surface is formed to form an alumina insulating film on the surface.

As shown in FIG. 11B, a plurality of unit heaters 105 are stacked horizontally (for example, 10 layers) in a rectangular heater housing 107, and are disposed on upper and lower portions of the unit heaters 105 of the uppermost and lowermost layers. The gap is formed to constitute the drying heater 104.

The drying heater 104 transfers heat generated by applying voltage to both ends of the planar heat dissipation member to the plate heat dissipation member 140, and uniformly heats the surrounding air by the heated plate heat dissipation member 140. do.

That is, the air introduced into the duct casing member 102 by the operation of the blower fan 103 is heated while passing through the plate-type heat dissipation member 140 and then discharged into the drum to dry the laundry.

Second Modification

As shown in FIG. 12A, in the drying heater 104a according to the second modified example, the planar heating member 120 is provided on an upper portion of the plate-shaped base member 110 in which the unit heater 105a has a flat plate shape. The plate-type heat conducting member 130 and the convoluted plate-type heat dissipation member 140 are sequentially stacked on the planar heating member 120.

The plate-type heat conducting member 130 is an anodized surface is made of an aluminum plate (110mm * 55mm) formed with an anodized film, that is, alumina (Al ₂ O ₃ ), other plate-type base member 110 and the surface Since the heat generating member 120 and the plate-shaped heat dissipation member 140 are the same as in the first modification, detailed description thereof will be omitted.

The planar heating member 120 is processed by a thin metal plate in a zigzag pattern, and the first and second connection members 142a and 142b are coupled to both ends of the heat radiating member 140, respectively, and the heat radiating member 140 is a fastening screw or bolt fastening to both ends of the heat conducting member 130, the planar heating member 120 and the base member 110 disposed below the first and second connecting members (142a, 142b) The fixing is done by

The unit heater 105a has a plate-type heat conducting member 130 inserted between the planar heat generating member 120 and the plate heat dissipating member 140, and is plate-shaped heat dissipating member that is convoluted to the planar heat generating member 120. The part where 140 meets the air layer without direct contact generates heat transfer by convection, so that a partial hot spot may occur when a high temperature is required. The heat of the planar heating member 120 can be evenly transferred to the plate-type heat radiating member 140 to increase the thermal conductivity efficiency.

As shown in FIG. 12B, the unit heaters 105a are horizontally stacked (eg, 10 layers) in the rectangular heater housing 107 and spaced above and below the uppermost and lowermost unit heaters 105a. To form a drying heater 104a.

The dry heater 104a according to the second modification transfers heat generated by applying voltage to both ends of the planar heat radiating member to the plate heat radiating member 140 and is heated by the plate heat radiating member 140. Heat the ambient air.

<Third Modification>

As shown in FIG. 13A, the dry heater 104b according to the third modification may include a planar heat generating member having a heat radiation fin shape in which a unit heater 105b is corrugated on an upper portion of a plate-shaped base member 110 having a flat plate shape. 120 is laminated.

The planar heating member 120 is processed by a thin metal plate in a zigzag pattern, and the first and second connection members 122a and 122b are coupled to both ends of the planar heating member 120, respectively, and the planar heating member 120 is fixed by fastening screws or bolts to both end portions of the base member 110 disposed below the first and second connection members 122a and 122b.

The plate-shaped base member 110 is formed by anodizing the surface of the aluminum plate to form an anodized insulating film that is insulated even at a voltage of 5 kV on each side.

The planar heating member 120 of the unit heater 105b has a heat-dissipating fin shape and heats heat generated by applying voltage to both ends of the unit heater 105b by directly exchanging heat with surrounding air.

As shown in FIG. 13B, the unit heaters 105b are horizontally stacked (10 layers) in the rectangular heater housing 107 and dried by forming a gap between upper and lower unit heaters 105b. The heater 104b is configured.

In the above first to third modified examples, the plate-shaped base member 110 is formed by patterning the planar heating member 120 on the insulated first insulating surface.

The plate-shaped base member 110 may be made of aluminum or an aluminum alloy having high thermal conductivity. In addition, any plate material having high thermal conductivity and withstanding the heat generation temperature of the planar heating member 120 may be used.

In addition, the plate-shaped base member 110 is an anodizing treatment on at least one of the two surfaces to form an insulating surface that is insulated and oxidized, and the planar heating member 120 is provided on the insulating surface Insulation is made with the heat generating member 120.

In addition, the planar heating member 120 may be mounted on the insulating surface of the plate-shaped base member 110 in a state where it is integrally attached, or may be made of a separate planar heating member.

The planar heating member 120 may be formed in a flat plate shape, may be used in the form of a corrugated heat dissipation fin, or when used in the form of a heat dissipation fin, various heat dissipation fins to widen the contact area with air It can be formed by bending in shape. In addition, the planar heating member 120 may heat-treat the surface to form an oxide film on the surface, or may be insulated from the plate-shaped base member 110 and the plate-shaped heat conductive member 130 to be described later by coating an insulating material. There is also.

The dry heater 104-104b of the present invention is configured by stacking a plurality of unit heaters 105-105b, and different unit heaters 105-105b when combining two or more unit heaters 105-105b. It includes an electrode terminal that can be electrically connected between the planar heating member 120 of the.

In addition, in the unit heaters 105-105b, the planar heating member 120 may not have a contact between the electrodes when stacked in a circular or elliptical casing in a circle, and one by welding or adhesion as necessary. You may have the above contact site | part.

The plate-shaped heat dissipation member 140 is provided at the upper portion of the planar heating member 120 to be corrugated to form a heat dissipation fin, and the plate-shaped heat dissipation member 140 is corrugated as described above. It can be formed in any heat radiation fin shape to expand the contact area with the surrounding air by bending the metal plate with high thermal conductivity.

In addition, the plate-type heat dissipation member 140 is made of aluminum or aluminum alloy with high thermal conductivity, it is preferable that the anodizing treatment is coated with an anti-oxidation and insulating material on the surface. The plate-type heat dissipation member 140 allows efficient heat exchange with a wide contact area while passing air through the curved portion, thereby allowing the surrounding air to be quickly heated.

Between the planar heat generating member 120 and the plate-shaped heat dissipation member 140 is provided with a plate-shaped heat conducting member 130 for efficiently transferring the heat of the planar heating member 120 to the plate-shaped heat dissipation member 140 desirable.

The plate-type thermally conductive member 130 is made of aluminum or aluminum alloy having high thermal conductivity, and is preferably anodized to coat an anti-oxidation and insulating material on its surface.

The dry heater 104-104b of the present invention is configured by stacking a plurality of unit heaters 105-105b inside a rectangular heater housing 107, and the unit heaters 105-105b are based on the planar heating member 120. If included as may be configured in other ways in addition to the first to third modifications described above. That is, the unit heaters 105 and 105b may be molded into a circular or elliptical shape and then inserted into the circular or elliptical casing.

For example, as illustrated in FIGS. 14A and 14B, the unit heater 105c may include a planar heating member 120 on an upper portion of the plate-shaped base member 110 having a flat plate shape, and the planar heating member 120. After the spirally molded plate-shaped heat radiating member 140 is laminated on the upper portion of the upper part), a circular-shaped unit heater 105c is inserted into the cylindrical heater housing 107 to dry the heater 104c. It is also possible to configure).

That is, in the drying heater 104 according to the first modification illustrated in FIG. 11A, the unit heater 105 is wound in a spiral shape and packaged in the cylindrical heater housing 107.

The drying heater 104c winds the plate-shaped base member 110, the planar heating member 120, and the plate-shaped heat radiating member 140 simultaneously with a winder to facilitate electrical wiring or electrode application. ) And attach the electrode terminal.

In addition, the drying heater 104c is preferably wound around the unit heater 105c to block the hole formed in the center of the cylindrical heater housing 107 so that the air is heated through the unit heater 105c.

The drying heater 104c transmits heat generated by applying voltage to both ends of the planar heat generating member 120 to the corrugated plate heat dissipating member 140, and is heated by the plate heat dissipating member 140. Heat the ambient air.

14A and 14B, the drying heater 104c illustrated in FIG. 14A and 14B is formed by laminating a unit heater 105c including a plate-shaped base member 110, a planar heating member 120, and a plate-type heat radiating member 140. 15A and 15B, the unit heater 105d including the plate heat dissipation member 140 and removing the plate-shaped heat dissipation member 140 and the planar heat dissipation member 120 having a heat dissipation fin shape, which is correlated with the plate base member 110, is formed. Of course, it is also possible to laminate and wind spirally.

The winding body in which the unit heaters 105d are laminated and wound in a spiral form the dry heater 104d by packaging in the cylindrical heater housing 107.

On the other hand, the drying heater (104-104d) is used in the drying heating unit 100 is installed in the washing machine or laundry dryer to blow dry air into the washing drum.

Hereinafter, the test results measured in comparison with the case where the conventional sheath heater is employed when the above-mentioned drying heater 104-104d is applied to the drying heating unit 100 for a washing machine or a laundry dryer will be described.

First, when there is no air flow inside the duct casing 102 of the drying heating unit 100, the temperature of the drying heater 104-104d of the present invention does not exceed a maximum of 137 ° C, but when a sheath heater is employed Rises to 447 ° C., where the surface temperature of the drying duct casing is found to be very hot at 377.6 ° C.

When the dry heaters 104-104d and the conventional sheath heater of the present invention are measured in comparison to the case where the blower fan 103 is operated in the heating unit 100, the dry heater of the present invention is characterized by the surface temperature of the heater. Is around 120 ° C, the air temperature at the air outlet 102b maintains around 90 ° C, while the conventional sheath heater maintains the air temperature at around 90 ° C at the air outlet 102b at around 250 ° C. Doing.

In the case of employing the dry heaters 104-104d of the present invention, the surface temperature of the duct casing 102 is measured to be around 27 ° C., which is similar to the room temperature of the measurement space, but in a very safe situation, the sheath heater of the duct casing 102 The surface temperature exceeded 130 ° C. and remained very hot. This means that parts located around the duct casing must use heat resistant parts.

In addition, the dry heater 104 of the present invention maintains about 94 ° C, the temperature of the sheath heater blows up to 260 ° C which is 13 to 20 ° C higher than 240 ° C which is the temperature at which wood can ignite If operation of (3) stops, fire may occur.

The dry heaters 104-104d of the present invention have a high energy efficiency because the difference between the temperature of the dry heater and the air temperature of the air outlet is about 6 ° C., with almost no heat loss, but the sheath heater has a temperature difference of about 150 ° C., which is energy efficient. It can be seen that this is low.

As a result of comparing and measuring power consumption, power consumption, and line current using the drying heater of the present invention and a drying heater equipped with a conventional sheath heater, the results are shown in Table 3 below.

In this case, the power consumption is a value measured when drying is performed for 30 minutes, which is a minimum setting time of a drying mode in a drum washing machine.

Heater type Power consumption
(Wh) Power Consumption
(W) Line current
(Arms) Voltage
(Vac) Invention 469 926 4.18 220 Sheath heater 1,058 2,108 9.59 220

As described above, the power consumption of the dry heater of the present invention is 469 Wh, but the sheath heater is 1,058 Wh, which is 2.2 times or more higher than the dry heater of the present invention.

On the other hand, the drying heaters 104-104d employed in the drying heating unit 100 described above also adopt a strip-like or thin film planar heating member 120 having a corrugated treatment thereof.

Therefore, as in the first and second embodiments of the dryer control system and control method according to the present invention, the driving voltage is maintained in accordance with the drum internal temperature T which is set in advance so as to keep the drum internal temperature constant and prevent a sudden drop. Apply a dual drive power method to selectively supply different dual drive powers, or apply a single drive power method and replace two heaters with different resistance values according to the preset drum internal temperature (T). The first and second heaters may be simultaneously driven and optionally driven in one of two heater heaters in which only one heater is driven.

In this case, when the thin film planar heating member is employed as the heating element of the heater as described in the first and second embodiments, the planar heating member is made of a thin metal sheet strip having a low thermal density, so that the planar heating member or the coil is relatively thick. Compared to the type heating element, relatively low temperature heat is generated, but heat exchange can be performed in a large area, and power consumption is reduced by utilizing characteristics having a fast temperature response.

Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and changes are possible within the technical spirit of the present invention, and such modifications and modifications belong to the appended claims.

The present invention is applicable to a control system and a control method for controlling to minimize power consumption of various home appliances.

* Description of symbols on the main parts of the drawings *
10,104-104d: Drying Heater 10a: First Heater
10b: second heater 11,107: housing
12: mica thin plate 12a-12c, 110: base member
13-13b, 120: planar heating member 14: through hole
15a-15c, 105-105d: unit heater 16: ceramic layer
17: strip 18: corrugation strip
21: key input 22: temperature sensor
23: control unit 24, 28, 29: switching element
25: motor 26: first drive power
27: second driving power source 30: connection point
31: second heater first 100: heater housing
102, 112: duct casing 102a: air inlet
102b: air outlet 103: blower fan
107: heater housing 130: thermoelectric member
140: heat dissipation member 142a, 142b: connection member

Claims (23)

A dryer control system for supplying heated air for drying laundry to a drum inside a laundry dryer or a laundry dryer at a predetermined temperature:
A first driving power source for applying the first electric power;
A second driving power source for applying a second power relatively lower than the first power;
A drying heater having a planar heating member made of a strip metal sheet having a low thermal density;
A temperature sensor for detecting an internal temperature of the drum of the dryer;
When the drum internal temperature is lower than the preset temperature, the first power of the first driving power source is applied to the drying heater. When the drum internal temperature is higher than the preset temperature, the second power of the second driving power source is applied to the drying heater. Dryer control system comprising a control unit for controlling to apply. The dryer control according to claim 1, further comprising a switching element for selectively applying any one of the first and second driving power sources to the drying heater according to a control signal applied from the control unit. system. The dryer control system of claim 1, wherein an applied voltage of the first drive power is AC 220V, and an applied voltage of the second drive power is AC 120V. The method of claim 1, wherein the first power of the first driving power source is set to a capacity for heating the drying heater to raise the drum internal temperature above the predetermined temperature,
And the second power of the second driving power source is set to a capacity that cannot raise the drum internal temperature above the predetermined temperature when heating the drying heater using only the second driving power source. The dryer control apparatus according to claim 1, wherein the drying heater comprises a plurality of unit heaters stacked on the inside of the cylindrical housing at intervals, and each of the plate-type base members is equipped with a planar heating member made of a thin metal plate. system. 6. The dryer control system according to any one of claims 1 to 5, wherein the planar heating member is formed by a corrugation. The method of claim 1, wherein the drying heater
A cylindrical housing;
And a plate-shaped base member made of a material having thermal conductivity and electrical insulation, respectively, and formed of a metal thin plate and insulated from the plate-shaped base member, and having a planar heating member that generates heat by being supplied with power. Dryer control system comprising a plurality of unit heaters stacked on. The dryer control system of claim 7, wherein each of the plurality of unit heaters further comprises a corrugated heat dissipation member formed of a thermally conductive material and mounted on the planar heat generating member. The method of claim 8, wherein the plurality of unit heaters are each formed of a thermally conductive material, characterized in that it further comprises a plate-type heat conducting member which is in contact with the insulated state between the planar heat generating member and the corrugated heat radiating member. Dryer control system. A dryer control system for supplying heated air for drying laundry to a drum inside a laundry dryer or a laundry dryer at a predetermined temperature:
A single drive power supply;
A first drying heater having a planar heating member made of a strip metal sheet having a low thermal density and generating heat corresponding to a first electric power when the driving power is applied;
A second drying heater having a planar heating member made of a strip metal sheet having a low thermal density and generating heat corresponding to a second power relatively higher than the first power when the driving power is applied;
A temperature sensor for detecting an internal temperature of the drum of the dryer;
When the drum internal temperature is lower than the preset temperature, the driving power is simultaneously applied to the first and second drying heaters, and when the drum internal temperature is higher than the preset temperature, the driving power is applied only to the first drying heater. Dryer control system comprising a control unit for controlling. The dryer control system of claim 10, further comprising a switching element configured to simultaneously apply the driving power to the first and second drying heaters or to apply only the first drying heater according to a control signal applied from the controller. . 11. The dryer control system according to claim 10, wherein the first and second drying heaters are connected in series or in parallel. The switching device of claim 10, wherein the first and second drying heaters are connected in parallel, the first drying heater is directly connected to a driving power source, and the second drying heater is selectively turned on by the controller. Dryer control system, characterized in that connected to the drive power through. The method of claim 10, wherein the first and second drying heaters are connected in series, and the connection point between the first and second drying heaters and one end of the second heater is connected to a driving power source through a switching element. Dryer control system characterized by. 15. The dryer control system according to any one of claims 10 to 14, wherein the planar heating member of the drying heater is formed by corrugation molding. In the dryer control method for supplying the heating air for drying the laundry into the drum of the laundry dryer or the laundry dryer at a predetermined temperature:
The first drying heater and the low heat density strip type having a planar heating member made of a strip-shaped metal sheet having low heat density when the operation of the dryer is started, and generating heat corresponding to the first power when the driving power is applied. It is provided with a planar heating member made of a thin metal plate and when the driving power is applied to the second drying heater that generates heat corresponding to the second power relatively higher than the first power at the same time by applying the driving power to the drum of the dryer Supplying heating air;
Detecting an internal temperature of the drum of the dryer;
When the drum internal temperature is lower than the preset temperature, the driving power is simultaneously applied to the first and second drying heaters, and when the drum internal temperature is higher than the preset temperature, the driving power is applied only to the first drying heater. Dryer control method comprising the step. 17. The method of claim 16, wherein the first and second drying heaters are connected in series or in parallel. 17. The method of claim 16, wherein the resistance value of the first drying heater is set relatively smaller than the resistance value of the second heater. In the dryer control method for supplying the heating air for drying the laundry into the drum of the laundry dryer or the laundry dryer at a predetermined temperature:
Supplying heating air to the drum of the dryer by applying a first electric power from a first driving power source to a drying heater having a planar heating member made of a strip-shaped metal sheet having a low heat density when the dryer starts; ;
Detecting an internal temperature of the drum of the dryer;
When the drum internal temperature is lower than the preset temperature, the first power of the first driving power is applied to the drying heater, and when the drum internal temperature is higher than the preset temperature, the second driving power which is relatively lower than the first power Drying control method comprising the step of applying a second power of the drying heater. 20. The method of claim 19, wherein the applied voltage of the first drive power is AC 220V, and the applied voltage of the second drive power is AC 120V. 20. The method of claim 19, wherein the first power of the first driving power source is set to a capacity for heating the drying heater to raise the drum internal temperature above the preset temperature,
And the second power of the second driving power is set to a capacity that cannot raise the drum internal temperature above the predetermined temperature when heating the drying heater using only the second driving power. The method of claim 19, wherein the drying heater increases the ratio of the second period during which the second power of the second driving power is applied to the first period during which the first power of the first driving power is applied as the drying time elapses. And a cycle in which the first period and the second period are repeated also increase as the drying time elapses. 20. The dryer control according to claim 19, wherein the drying heater includes a plurality of unit heaters stacked on the inside of the cylindrical housing at intervals, and each of the plate-type base members is equipped with a planar heating member made of a thin metal plate. Way.

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