US20110283733A1

US20110283733A1 - Refrigerator

Info

Publication number: US20110283733A1
Application number: US13/133,161
Authority: US
Inventors: Yufa Bai; Liang Gao; Songtao Lu; Qiwu Zhu
Original assignee: BSH Bosch und Siemens Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2008-12-08
Filing date: 2009-12-18
Publication date: 2011-11-24
Also published as: CN101749908B; WO2010066738A2; EP2373940A2; WO2010066738A3; CN101749908A

Abstract

A refrigerator includes a dispenser provided in a door and having a dispenser casing, which is provided with a first region and a second region located close to the first region. The first region and the second region are adjacent to a heat insulating layer of the door. A first heater is arranged in the first region for supplying heat to the dispenser casing and a second heater is arranged in the second region for supplying heat to the dispenser casing, with the first heater and the second heater being controlled independently.

Description

TECHNICAL FIELD

The invention relates to a refrigerator, especially to a household or commercial refrigerator provided with a dispenser.

BACKGROUND ART

The freezing compartment of a refrigerator can usually reach a temperature of lower than minus ten degrees Celsius. Although the refrigerator body and the door of the refrigerator are provided with heat insulating layers to avoid losing of cold energy by reducing heat exchange between the cold air within the refrigerator and the surrounding environment, with the increasing in the capacity of the refrigerator and in the number of the components (for example, a dispenser for dispensing water or ice) provided on the refrigerator door, some portions of the refrigerator door which are exposed to the atmosphere may have a relatively low temperature under the influence of the storage compartment. When the difference between the temperature of the surfaces exposed to the atmosphere and the temperature of the atmosphere reaches a dew point, condensed water will appear on these surfaces.
It is known in prior art that the temperature of the specific surfaces of a refrigerator can be increased by providing a heating element so as to prevent condensate dew from being generated. U.S. Pat. No. 6,862,891 B1 discloses a refrigerator having a heating element located near an ice dispensing apparatus and a control unit connected with the heating element. The control unit is configured such that the voltage supplied to the heating element is variable, thereby the heating element may be operated at different non-zero voltages for reducing energy consumption. The background part of the patent further discloses that manufacturers can install two anti-condensation heaters, wherein one heater is served as a standby heater and only used after a failure of the other heater.
For various reasons such as the door generally has an irregular shape at a location which is corresponded to a dispenser casing, various portions of the dispenser casing have different distances from an ice transfer passage which passes through the door, the heat insulating layer has different thicknesses at different portions of the dispenser casing, etc., different areas of the dispenser casing may have different dewing possibilities. Thus, in a dew prevention/removing process, some areas of the door may be overheated while other areas may have a temperature that is too low to prevent the generation of condensate dew.

SUMMARY OF THE INVENTION

The object of the invention is therefore to overcome at least one of the above technical problems in the prior art, so that it is possible to prevent condensate dew from being generated on the dispenser casing more effectively with a higher efficiency.
The invention in one aspect relates to a refrigerator comprising: a refrigerator body defining at least one storage space; a door connected to the refrigerator body for closing at least a part of the storage space, a heat insulating layer is provided in the door; a dispenser provided in the door, the dispenser comprises a dispenser casing, the dispenser casing comprises a first region and a second region located close to the first region, the first region and the second region are adjacent to the heat insulating layer; and a first heater arranged in the first region for supplying heat to the dispenser casing, characterized in that it further comprises a second heater arranged in the second region for supplying heat to the dispenser casing, wherein the first heater and the second heater are controlled independently.
Therefore, different heaters may be properly disposed according to the condensate generation characteristics in different areas of the dispenser casing, and it may prevent the occurring of condensation or removing the condensate dew already generated more effectively with a higher efficiency by individually controlling these different heaters.
Other features being regarded as the characteristics of the invention individually or in combination with other features are defined in attached claims.
According to a preferred embodiment of the invention, the second region is surrounded by the first region, thereby even if one heater does not work, the heat generated by the other heater can also cover the area which is corresponded to the heater that does not work.
According to a particularly preferred embodiment of the invention, the first heater comprises two heating segments spaced at a predetermined distance, at least a part of the second heater is located between the two heating segments.
According to a preferred embodiment of the invention, the refrigerator further comprises an ice transfer passage for transferring ice, the first heater and/or the second heater are arranged at least partly around the ice transfer passage.
According to a preferred embodiment of the invention, the powers of the first heater and the second heater are different.
According to a preferred embodiment of the invention, the refrigerator comprises a control unit and a sensing unit for detecting at least one ambient parameter, the first heater is controlled automatically by the control unit based on the detected ambient parameter(s).
According to a preferred embodiment of the invention, the second heater is turned on in an auxiliary heating mode which is activated manually, so as to supply additional heat to the dispenser casing. By means of the combination of intelligent mode and manual mode, the construction of the control unit can be relatively simple, thereby it is possible to realize the dew prevention/removing function of the refrigerator used in different climate environment and/or in different degrees of use with a lower cost. Additionally, in the condition that there is no condensate dew generated, the second heater can be turn off directly by the user or maintain the turn off state, so unnecessary energy consumption can be reduced and thus the efficiency of dew prevention/removing can be improved.
In an alternative embodiment, the second heater is controlled by the control unit automatically.
According to a preferred embodiment of the invention, the second heater is turned on only when ambient temperature is higher than a predetermined value and/or ambient relative humidity is higher than a predetermined value.
According to a preferred embodiment of the invention, the refrigerator comprises a heat conducting element which covers at least a part of the inner surface of the dispenser casing, the heat conducting element is at least close to the first heater and/or the second heater for transmitting the heat generated by the first heater and/or the second heater to the dispenser casing. In this way, the heat generated by the heater can be transmitted to the dispenser casing rapidly and evenly. On one hand, this configuration can prevent the portions of the dispenser casing which are closer to the heater from being overheated and the portions of the dispenser casing which are farther from the heater from being underheated and thus generating condensate dew, so that it can be expected that condensation on the dispenser casing can be avoided with a reasonable energy consumption. On the other hand, by means of the heat conducting function of the heat conducting element, the reaching area of the heat generated by the heater can be enlarged by the heat conducting element. That is to say, the heat generated by the heater may form a heat source for the heat conducting element and will be transmitted quickly by the heat conducting element, so that the area covered by the heater can be advantageously reduced. For example, it is possible that only the portions of the dispenser casing which are likely to occur condensation can be provided with a heater while other portions of the dispenser casing which are not likely to occur condensation are only covered and supplied with heat by the heat conducting element.
According to a preferred embodiment of the invention, the dispenser casing defines a dispensing cavity for receiving at least a part of an external container, the dispensing cavity comprises a dispensing cavity wall extending in a longitudinal direction, and the heat conducting element covers at least a major portion of the dispensing cavity wall.
In a particularly preferred embodiment of the invention, the first heater and the second heater are not arranged on the dispensing cavity wall, or only distributed in the marginal region of the dispensing cavity wall, thereby the possibility that the temperature of the dispensing cavity wall, which is prone to be touched by the user, is notably higher than ambient temperature is greatly reduced.
The structure as well as other objects and advantages of the invention will be apparent from the description to the preferred embodiments with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

As a part of the description and for further understanding of the invention, the following drawings illustrate some preferred embodiments of the invention and are used to illuminate the principle of the invention together with the following detailed description. In the drawings,

FIG. 1 is a schematic perspective view of a refrigerator according to a preferred embodiment of the invention.

FIG. 2 is a schematic partial sectional view taken along a direction indicated by line I-I of FIG. 1.

FIG. 3 is a schematic view of a partly assembled door of the according to the preferred embodiment of the invention.

FIG. 4 is a schematic layout of a heating unit of a dispenser casing according to a preferred embodiment of the invention.

FIG. 5 is a schematic block diagram of the refrigerator according to a preferred embodiment of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Please refer to the drawings, in particular FIGS. 1 and 2. A refrigerator 1 comprises a refrigerator body 2 and two doors 3 connected to the refrigerator body 2, as shown in FIGS. 1 and 2.
The refrigerator body 2 comprises an outer shell 11, an inner shell 12 and a heat insulating layer 6 located between the outer shell 11 and the inner shell 12. In this embodiment, the heat insulating layer 6 is a foam-based insulating layer and is formed by foaming a heat insulating foam material. The refrigerator body 2 defines at least one storage space for storing food. In this embodiment, the storage space comprises a freezing compartment 7 and a refrigerating compartment (not shown) which are juxtaposed with each other.
Each door 3 is pivotably connected to the refrigerator body 2 by a hinge 4, and is rotatable about a corresponding rotation axis parallel to a longitudinal axis. As shown in FIG. 2, it is also provided with a foam-based insulating layer 6 in the door 3. The doors 3 are normally closed to avoid escape of cold air from the freezing compartment 7 and the refrigerating compartment. When desired, the user may open a corresponding door 3 to perform an operation, such as taking out food from the freezing compartment or refrigerating compartment, or putting food into a corresponding storage compartment. The user can open or close the doors 3 by means of handles 5.
In this embodiment, each door 3 is configured to completely open or completely close a corresponding storage compartment. It should be appreciated that the invention is not limited to this, and other embodiments are also possible. For example, in an alternative embodiment, one of the storage compartments may be opened or closed by two doors 3. That is to say, each door 3 may only open or close a part of such a storage compartment.
The door 3 which is corresponded to the freezing compartment 7 (hereinafter referred to freezing compartment door) is provided with a dispenser 8 to allow a user to take out ice and/or beverage (for example water), such as ice stored in the freezing compartment and water stored in a water tank arranged in the refrigerating compartment, without opening the door 3. Although in this embodiment the dispenser 8 is arranged in the door 3 which is corresponded to the freezing compartment, it should be appreciated that it is also possible to arrange the dispenser 8 in a suitable way in the door 3 which is corresponded to the refrigerating compartment.
As shown in FIGS. 2 and 3, the freezing compartment door 3 comprises a door panel 13 forming its front surface and a lining 23 facing towards the freezing compartment 7 when the freezing compartment door 3 is in its closed position. In this embodiment, the door panel 13 is made of a sheet metal, and both sides of the door panel 13 are bent backwardly and extend to form first and second longitudinal sidewalls 48 and 49 respectively. The heat insulating layer 6 is in tight contact with the door panel 13 and the first and second longitudinal sidewalls 48 and 49.
The door panel 13 has an opening 9 which is corresponded to the dispenser 8, the opening 9 has a substantially square or rectangular shape. The dispenser 8 comprises a dispenser casing 10 received between the door panel 13 and the lining 23. The dispenser casing 10 forms a cavity 14, which is inwardly recessed and has an open front end. The shape and dimension of the front end of the cavity 14 substantially correspond to that of the opening 9. The lining 23 protrudes toward the freezing compartment 7 at a location which is corresponded to the dispenser casing 10, with a predetermined distance between the protruding portion of the lining 23 and the dispenser casing 10 for disposing the heat insulating layer 6.
The dispenser 8 comprises a partition plate 15 within the cavity 14. The partition plate 15 is parallel to a horizontal plane and separates the cavity 14 into an upper portion and a lower portion. The portion of the cavity 14 located below the partition plate 15 forms a dispensing cavity 16 whose front end is kept open. The dispensing cavity 16 is configured to accept at least a part of an external container such as a cup. In this embodiment, the dispensing cavity 16 is recessed backwardly from the front surface of the door 3 at a certain curvature to a predetermined depth.
The dispensing cavity 16 has a substantially flat support wall 17 for stably putting the external container thereon. The support wall 17 has a plurality of thin through holes (not shown), through which any liquid that is splashed out or overflows accidentally during an ice or water dispensing process flows into a water gathering slot 19 arranged below the support wall 17.
The refrigerator 1 comprises a control panel 20 arranged on the freezing compartment door 3. The control panel 20 comprises a display screen 21 and a plurality of buttons or touch areas 22 for controlling the refrigerator 1. The display screen 21 can display the state of the refrigerator 1 and/or selectable parameters, etc.
In this embodiment, the control panel 20 is arranged along the upper end of the opening 9, closely adjacent to the dispensing cavity 16. The portion of the opening 9 located above the partition plate 15 is adapted to be conformed to the outer profile of the control panel 20, such that the control panel 20 can be engaged to the corresponding edge of the opening 9. The portion of the cavity 14 located above the partition plate 15 is shielded by the control panel 20.
The dispenser casing 10 comprises a cavity wall delimiting the cavity 14. The cavity wall comprises a first portion 24 located below the partition plate 15. The first portion 24 comprises a longitudinal wall 30 forming a longitudinal boundary of the dispensing cavity 16. The longitudinal wall 30 is perpendicular to the horizontal plane and has a substantially arc-shaped cross-section. The longitudinal wall 30 has a rear surface closely adjacent to the heat insulating layer 6 and an outer surface exposed to the atmosphere.
The first portion 24 further comprises a bottom wall 31 which is connected to the lower end of the longitudinal wall 30 and extends forwardly. The bottom wall 31 is located below the support wall 17 and spaced from the support wall 17 by a certain distance so as to form the above-mentioned water gathering slot 19.
The cavity wall of the dispenser casing 10 comprises a second portion 25 which is connected to the upper end of the first portion 24 and is located above the partition plate 15. The second portion 25 comprises an inclined wall 26 which extends from the longitudinal wall 30 and is inclined forwardly. The inclined wall 26 comprises a through hole 27 which allows ice to pass therethrough. The through hole 27 is configured as a part of an ice transfer passage 29. The ice transfer passage 29 is used for transferring ice from an ice storage unit 28 located within the freezing compartment 7 to the dispensing cavity 16. The second portion 25 further comprises a top wall 32 which forms the upper boundary of the cavity 14. The second portion 25 has a hole 33 through which a water supply pipe (not shown) passes, which water supply pipe transfers drinkable water to the dispensing cavity 16.
An ice discharge pipe 34 forming a major part of the ice transfer passage 29 is embedded in the freezing compartment door 3. One end of the ice discharge pipe 34 is connected to the second portion 25 and is in communication with the through hole 27. The other end of the ice discharge pipe is oriented towards a discharge outlet of the ice storage unit 28 within the freezing compartment 7 when the freezing compartment door 3 is closed. Thereby, the ice discharged from the ice storage unit 28 enters into the ice discharge pipe 34, and then is guided to the dispensing cavity 16 by means of an ice outlet 18 provided in the partition plate 15.
As shown in FIG. 2, the portion of the cavity 14 which lies above the partition plate 15 is shielded by the control panel 20, however, the second portion 25 of the dispenser casing 10 is still in communication with the atmosphere, that is, the second portion 25 is still exposed to the atmosphere, because the partition plate 15 is provided with the ice outlet 18 which is in communication with the portion of the cavity 14 which lies above the partition plate 15.
To prevent air within the freezing compartment 7 from escaping from the freezing compartment 7 through the ice transfer passage 29 or prevent outside air from entering into the freezing compartment 7 through the ice transfer passage 29, the dispenser 8 is equipped with a closure element 36 for opening or closing the ice transfer passage 29. Usually, the ice transfer passage 29 is closed by the closure element 36. When there is a need for dispensing ice, the ice transfer passage 29 is opened by means of the closure element 36 to allow the transfer of ice. The shape and dimension of the closure element 36 are substantially corresponded to that of the through hole 27, such that in the closed position, the closure element 36 closes the through hole 27 and thus closes the ice transfer passage 29. In this embodiment, the closure element 36 is connected to the second portion 25 of the dispenser casing 10 and is received in the cavity 14.
Under the influence of the freezing compartment 7, the temperature of the dispenser casing 10 is usually lower than room temperature/ambient temperature. When the difference between ambient temperature and the temperature of the dispenser casing 10 reaches a dew point temperature, condensed water will be generated on the dispenser casing 10. The condensation possibility of the second portion 25 of the dispenser casing 10 is relatively high due to the fact that it is close to the ice discharge pipe 34 and forms a part of the ice transfer passage 29. Therefore, the refrigerator 1 is provided with a heating unit 37 for increasing the surface temperature of the dispenser casing 10. As shown in FIG. 2, the heating unit 37 is arranged between the dispenser casing 10 and the heat insulating layer 6.
FIG. 4 is a schematic diagram of the heating unit 37 according to a preferred embodiment of the invention. As shown in FIG. 4, the heating unit 37 comprises a first heater 38 for supplying heat to the dispenser casing 10 and a second heater 39 close to the first heater 38. The first heater 38 and the second heater 39 are preferably resistance heaters, i.e. performing heating by resistors.
In order to evenly transmit the heat generated by the first heater 38 and the second heater 39 to the dispenser casing 10, the heating unit 37 comprises a first heat conducting element 40 for transmitting the heat generated by the first heater 38 and the second heater 39 to the dispenser casing 10. In this embodiment, the first heat conducting element 40 is an aluminum foil, which has a good heat conductivity.
The first heat conducting element 40 has a hole (not shown) which is corresponded to the through hole 27. The first heater 38 and the second heater 39 can be arranged according to the distribution characteristics of condensate dew on the dispenser casing 10. In this embodiment, the first heater 38 comprises a plurality of arc-shaped heating segments 35 arranged around the hole. The second heater 39 is arranged close to the first heater 38 and preferably comprises a portion located between the heating segments 35 of the first heater 38. Preferably, this portion has a shape that corresponds to the heating segment 35.
After the first heater 38 and the second heater 39 are arranged in a predetermined pattern on one side of the first heat conducting element 40, the other side of the first heat conducting element 40 is closely attached to the inner side of the dispenser casing 10.
The heating unit 37 is adhered to the inner side of the dispenser casing 10 by means of adhesive means (not shown), with the hole of the first heat conducting element 40 being aligned with the through hole 27. The first heat conducting element 40, the first heater 38 and the second heater 39 are flexible and deformable, such that the portion of the heating unit 37 located between line A and line B is arranged on the inclined wall 26, the portion thereof located above line A is bent and then is adhered to the top wall 32 of the dispenser casing, and the portion thereof located below line B is bent and then is connected to the upper end of the longitudinal wall 30. Thereby, in this embodiment, the first heater 38 is mainly distributed on the inclined wall 26 and the top wall 32 of the dispenser casing 10. The lower end portion of the first heater 38 extends to the upper end of the longitudinal wall 30. The heating segment 35 closest to the through hole 27 is arranged around the through hole 27. The major portion of the second heater 39 is arranged on the inclined wall 26. The portion located below line B of the second heater extends to the upper end of the longitudinal wall 30 together with the first heater 38.
In this embodiment, the first heater 38 and the second heater 39 are distributed on a first region 51 and a second region 52 of the dispenser casing 10 respectively. The first region 51 and the second region 52 are close to each other, but they do not overlap each other. The first region 51 covers the majorities of the inclined wall 26 and the top wall 32 as well as the upper end portion of the longitudinal wall 30 which is close to the inclined wall 26. The second region 52 has an area smaller than the first region 51 and is surrounded by the first region 51.
Preferably, the power of the second heater 39 is lower than that of the first heater 38. Preferably, the power density of the second heater 39 is configured in such a way that the dispenser casing 10 is not subjected to overheating even if the second heater 39 is turned on for a long time or always turned on.
According to a preferred embodiment of the invention, the side of the longitudinal wall 30 which faces the heat insulating layer 6 is provided with a second heat conducting element 50. The upper end of the second heat conducting element 50 is connected to the first heater 38 and the second heater 39 or connected to the first heat conducting element 40. Thereby, the first and second heaters 38 and 39 and/or the first heat conducting element 40 serve as a heat source for the second heat conducting element 50.
Since the second heat conducting element 50 has a good heat conductivity, the heat generated by the first and second heaters 38 and 39 is also transmitted to other portions of the longitudinal wall 30 that are not equipped with any heating element, such that the temperature of the whole longitudinal wall 30 can be increased so as to avoid the generation of condensate dew. Since the longitudinal wall 30 is located relatively far from the ice transfer passage 29, such a configuration allows to avoid the generation of condensate dew on the longitudinal wall 30 without arranging any heater on the longitudinal wall 30 or merely by arranging a heater on the marginal region of the longitudinal wall 30 where it is not prone to be touched by the user. Thus, energy consumption can be lowered. In addition, the situation that the user touches the high temperature region of the longitudinal wall 30 can be avoided.
Preferably, the second heat conducting element 50 comprises a metal foil having a good heat conductivity, such as aluminum foil. In a particularly preferable embodiment, the second heat conducting element 50 covers at least substantially most of the longitudinal wall 30. For example, the longitudinal wall 30 is entirely covered by the second heat conducting element 50. The second heat conduction element 50 is preferably adhered to the inner side of the longitudinal wall 30 by means of adhesive means, such as an adhesive tape.
In order to prevent the portions of the longitudinal wall 30 which are prone to be touched by the user from reaching a temperature which is notably higher than ambient temperature, it is preferably that only an edge area of the second heat conducting element 50 contacts the first and second heater 38 and 39. Particularly preferably, the upper end of the second heat conducting element 50 contacts the first and second heater 38 and 39.
In the above embodiments, the first and second heater 38 and 39 extend to the upper end of longitudinal wall 30. However, the invention is not limited to this. For example, in an alternative embodiment, the first and second heater 38 and 39 do not extend to the longitudinal wall 30; rather, the heat conducting element 50 may extend to a extend that is beyond the longitudinal wall 30 (for example, extend to the inclined wall 26) so as to be contacted with the first and second heater 38 and 39 which lie outside the longitudinal wall 30.
The first longitudinal sidewall 48 of the freezing compartment door 3 is close to the rotation axis of the freezing compartment door 3, while the second longitudinal sidewall 49 opposite to the first longitudinal sidewall 48 is far away from the rotation axis of the freezing compartment door 3 and close to the door of the refrigerating compartment. According to a preferred embodiment of the invention, the freezing compartment door 3 is provided with a third heater 47 for supplying heat to the second longitudinal sidewall 49, so as to avoid the generation of condensate dew on the second longitudinal sidewall 49 due to the difference between the surface temperature and ambient temperature. In this embodiment, the third heater 47 is attached to the inner side of the second longitudinal sidewall 49.
The second longitudinal sidewall 49 is provided with a third heat conducting element 54 attached to the inner side thereof. The third heat conducting element 54 is located between the third heater 47 and the inner surface of the second longitudinal sidewall 49 to evenly transmit the heat generated by the third heater 47 to the second longitudinal sidewall 49. Preferably, the third heat conducting element 54 is attached to the inner surface of the second longitudinal sidewall 49 by adhesive means (for example, an adhesive tape).
It is most preferably to arrange the third heater 47 and/or the third heat conducting element 54 on a region of the second longitudinal sidewall 49 which is corresponded to the dispenser 8 in the longitudinal direction. Preferably, the third heater 47 at least partially overlaps the dispenser 8 in a transverse direction.
FIG. 5 shows a structural schematic diagram of the refrigerator according to a preferred embodiment of the invention. Now a control method of the first heater 38 and the second heater 39 will be described with reference to FIG. 5.
The refrigerator 1 comprises a control unit 41, and an input unit 43 and a display unit 44 coupled to the control unit 41 respectively, wherein the input unit 43 comprises the buttons or touch areas 22 located on the control panel 20, and the display unit 44 comprises the display screen 21 located on the control panel 20. The control unit 41 comprises a microprocessor and a memory unit, such that some components of the refrigerator 1 such as the first heater 38 can be automatically controlled by means of a program stored in the memory unit.
The refrigerator 1 further comprises a sensing unit 42 for detecting at least one ambient parameter. The sensing unit 42 is coupled to the control unit 41 and feeds back the detected parameter(s) to the control unit 41. In this embodiment, the sensing unit 42 comprises a temperature sensor for detecting ambient temperature. The sensing unit 42 controls the operation of the first heater 38, including turning on and turning off the first heater 38, based on the detected ambient temperature.
In a preferred embodiment, when the detected ambient temperature is lower than zero degree Celsius, the first heater 38 is turned off. When the detected ambient temperature is between 0° C. and 10° C., the first heater 38 operates at a first output power and/or operates at a duty cycle of lower than 0.3. When the detected ambient temperature is higher than 10° C. and lower than 15° C., the first heater 38 is turned on at a second output power, or the first heater 38 is turned on and off in an alternative manner at a second duty cycle (for example, 0.4). When the detected ambient temperature is higher than 15° C. and lower than 25° C., the first heater 38 is turned on at a third output power and/or operates at a predetermined third duty cycle (for example, 0.5).
In an alternative embodiment, the sensing unit 42 further comprises a humidity sensor for detecting ambient relative humidity. The control unit 41 controls the operations of the first heater 38 based on the detected ambient temperature, ambient relative humidity and other factors.
The second heater 39 is controlled independently of the first heater 38. According to the invention, the second heater 39 is turned on only in an auxiliary heating mode, which is only manually activated by the user. Thus, the user can, according to the dewing phenomenon on the refrigerator 1, make an active decision freely on whether the second heater 39 should be activated to increase heat for dew prevention/removing.
In a preferred embodiment, the auxiliary heating mode is activated by means of switching means 45 arranged on the freezing compartment door 3. The switching means 45 is preferably arranged on the dispenser 8 or near the dispenser 8. Particularly preferably, the switching means 45 is arranged on the partition plate 15.
In an embodiment, the switching means 45 is electrically connected to the second heater 39, and the turning on and off states of the second heater 39 are determined by the switching on and off states of the switching means 45. Preferably, when the switching means 45 is in a switching off state, the refrigerator 1 operates in a normal mode, the first heater 38 is turned on or off based on an instruction from the control unit 41, and the second heater 39 is turned off. When the user operates the switching means 45 to switch on it, the refrigerator 1 activates the auxiliary heating mode, the second heater 39 is turned on to supply additional heat to the dispenser casing 10, and at the same time the first heater 38 is turned on or off based on an instruction from the control unit 41.
The switching means 45 can be provided independently of the control unit 41, for example, there is no coupling between the switching means 45 and the microprocessor of the control unit 41. In an alternative embodiment, the switching means 45 is connected to the control unit 41, for example, the display unit 44 can display whether the refrigerator 1 is under the normal heating mode or the auxiliary heating mode, or the user can select the parameters displayed on the display unit 44 by means of the switching means 45 in order to activate the auxiliary heating mode.
The second heater 39 can be turned off by manually switching off the switching means 45, so that the auxiliary heating mode is ended. However, in an alternative embodiment, the second heater 39 can also be automatically turned off. For example, the control unit 41 is configured in such a manner of automatically turning off the second heater 39 after the second heater 39 has been turned on for a predetermined time, such as 15 minutes. This can be achieved by virtue of timing means connected to the control unit 41. The timing means is configured in such a way that it generates a signal when the second heater 39 has been turned on for a predetermined time, and then the second heater 39 is turned off based on this signal. Under the condition that the switching means 45 is not coupled to the microprocessor of the control unit 41, this can be achieved by timing means connected to the switching means 45 or timing means embedded in the switching means 45.
In an alternative embodiment, the second heater 39 is also automatically controlled by the control unit 41. For example, the second heater 39 is turned on only when ambient temperature is higher than a predetermined value (for example, 30° C.) and/or ambient relative humidity is higher than a predetermined value (for example, 80%).
In the embodiment shown in FIG. 5, the control manner of the third heater 47 is the same as that of the first heater 38, that is, being automatically controlled by the control unit 41 based on the detected parameters. In a preferred embodiment, the parameters comprise ambient temperature, ambient relative humidity and/or the temperature of the sidewall 49, such that the control unit 41 can control the third heater 47 based on ambient temperature, ambient relative humidity and/or the temperature of the sidewall 49, so as to for example determine whether or not the third heater 47 should be turned on, or determine the frequency of turning on and off or the duty cycle of the third heater 47.

Claims

1-12. (canceled)

13. A refrigerator, comprising:

a refrigerator body defining at least one storage space;

a door connected to the refrigerator body for closing at least a part of the storage space, said door being provided with a heat insulating layer;

a dispenser provided in the door and comprising a dispenser casing, said dispenser casing comprising a first region and a second region located close to the first region, said first and second regions being arranged adjacent to the heat insulating layer;

a first heater arranged in the first region for supplying heat to the dispenser casing; and

a second heater arranged in the second region for supplying heat to the dispenser casing, wherein the first heater and the second heater are controlled independently.

14. The refrigerator of claim 13, wherein the second region is surrounded by the first region.

15. The refrigerator of claim 13, wherein the first heater comprises two heating segments spaced at a predetermined distance, at least a part of the second heater being located between the two heating segments.

16. The refrigerator of claim 13, further comprising an ice transfer passage for transferring ice, at least one of the first and second heaters being arranged at least partly around the ice transfer passage.

17. The refrigerator of claim 13, wherein the first heater operates at a power which is different than a power of the second heater.

18. The refrigerator of claim 13, further comprising a control unit and a sensing unit for detecting at least one ambient parameter, said first heater being controlled automatically by the control unit in response to the detected ambient parameter.

19. The refrigerator of claim 13, wherein the second heater is configured to operate in an auxiliary heating mode which is activated manually, so as to supply additional heat to the dispenser casing.

20. The refrigerator of claim 18, wherein the second heater is controlled by the control unit automatically.

21. The refrigerator of claim 20, wherein the second heater is turned on only when an ambient temperature is higher than a predetermined value and/or ambient relative humidity is higher than a predetermined value.

22. The refrigerator of claim 13, further comprising a heat conducting element which covers at least a part of an inner surface of the dispenser casing, said heat conducting element being arranged at least close to at least one member selected from the group consisting of the first heater and the second heater for transmitting the heat generated by the member to the dispenser casing.

23. The refrigerator of claim 22, wherein the dispenser casing defines a dispensing cavity for receiving at least a part of an external container, said dispensing cavity comprising a dispensing cavity wall extending in a longitudinal direction, with the heat conducting element covering at least a major portion of the dispensing cavity wall.

24. The refrigerator of claim 23, wherein the first and second heaters are arranged distal to the dispensing cavity wall.

25. The refrigerator of claim 23, wherein the first and second heaters are arranged in a marginal region of the dispensing cavity wall.