REFRIGERATOR

Abstract

An ice making device in a refrigerator including light sensors to detect an ice level in the ice bucket. An ice level sensing unit is positioned lower than an upper edge of the ice bucket and thus can detect ice level even when the ice bucket is not completely full. The ice level sensing unit includes one or more pairs of light emitting sensor and light receiving sensor. When ice in the ice bucket accumulates to a detectable level, the amount of light emitted from the light emitting sensor and received by the light receiving sensor can be blocked accordingly.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is based on and claims priority from Korean Patent Application No. 10-2016-0052219, filed on Apr. 29, 2016, the disclosure of which is incorporated herein in its entirety by reference for all purposes.

TECHNICAL FIELD

Embodiments of the present disclosure relate to refrigerators, and more particularly, to ice making and dispensing mechanisms in refrigerators.

BACKGROUND

A refrigerator is an appliance used for storing food or other times at low temperature, e.g., in a frozen state or refrigerated.

The interior of the refrigerator is cooled by cold air circulating therein. Cold air can be continuously generated as a refrigerant recycling through compression, condensation, expansion and evaporation. Cold air supplied in the refrigerator is uniformly distributed by convection.

The refrigerator includes a main body having a rectangular parallelepiped shape with a front opening. A refrigeration compartment and a freezer may be disposed in the main body. A refrigeration compartment door and a freezer door may cover the front of the main body. Drawers, racks, storage boxes and the like for sorting and storing different kinds of items may be disposed in the internal storage space of the refrigerator.

In general, a top-mount-type refrigerator has a freezer located on top of a refrigeration compartment. In contrast, a bottom-freeze-type refrigerator has a freezer located under the refrigeration compartment. This enables a user to conveniently access the refrigeration compartment. On the other hand, this may be inconvenient for a user to access the freezer, if the user has to bend or lower his or her body to reach, e.g., to take out ice pieces.

Some bottom-freeze-type refrigerators have an ice dispenser disposed in a refrigeration compartment door located at the upper side of the refrigerator. In this case, an ice-making device for supplying ice may be disposed in the refrigeration compartment door or the interior of the refrigeration compartment.

More specifically, water is supplied to the ice tray and freezes into ice pieces therein. The ice tray may be heated slightly after ice forms. Thereafter, an ice-releasing device is driven to release the ice pieces toward the ice bucket. However, if the stack height of the ice pieces in the bucket comes close to the ice tray, it may be difficult to release the ice pieces from the ice trays, causing the ice pieces to adhere to the ice tray. Thus, a sensing unit capable of sensing the amount of ice in the ice bucket is provided in the ice-making device.

However, the sensing unit typically uses a rotatable lever. When the lever is rotated, ice pieces in the ice bucket may interfere with the lever. If ice-making water leaks and freezes on a rotation shaft of the lever, the rotation of the level can be hindered, which can reduce the efficiency and accuracy of the sensing unit.

PRIOR ART DOCUMENTS

Patent Documents

• Patent Document 1: Korean Patent Application Publication No. 10-2010-0063241 (published on Jun. 11, 2010)

SUMMARY

Embodiments of the present disclosure provide a refrigerator which includes an ice-making device with improved sensing efficiency for detecting an ice level or fullness.

According to one embodiment, a refrigerator includes: a main body having a storage space; a door installed in the main body to cover the storage space; an ice-making compartment installed in the door or inside the main body; and an ice-making device disposed inside the ice-making compartment. The ice-making device includes an ice-making assembly configured to produce ice pieces; an ice bucket configured to store the ice pieces produced in the ice-making assembly; and an ice level sensing unit configured to sense the level of the ice in, or fullness of, the ice bucket. The sensing unit is located lower than an upper edge (the top opening) of the ice bucket.

The ice level sensing unit includes a light-emitting sensor installed on one sidewall of the ice-making compartment and configured to emit light; and a light-receiving sensor installed on the other sidewall of the ice-making compartment and configured to sense the light emitted from the light-emitting sensor.

The ice bucket includes a first sidewall having a first cutout portion so that light emitted from the light-emitting sensor travels toward the light-receiving sensor through the first cutout portion; and a second sidewall configured to face the first sidewall and having a second cutout portion so that light emitted from the light-emitting sensor travels toward the light-receiving sensor through the second cutout portion.

The light-emitting sensor and the light-receiving sensor are spaced apart in a transverse direction of the ice bucket.

A control unit is also included and configured to determine the fullness of the ice pieces in the ice bucket based on the amount of light sensed by the light-receiving sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating the configuration of an exemplary refrigerator according to one embodiment of the present disclosure.

FIG. 2 is a side view of the exemplary refrigerator illustrated in FIG. 1.

FIG. 3 is an exploded perspective view illustrating the configuration of an exemplary ice-making device of the refrigerator illustrated in FIG. 1.

FIG. 4 is a side sectional view illustrating the configuration of the exemplary ice-making device of the refrigerator illustrated in FIG. 1.

FIG. 5 is a front view illustrating the exemplary ice-making device of the refrigerator illustrated in FIG. 1.

FIG. 6 is an operation state view illustrating an exemplary method of sensing ice fullness by an ice level sensing unit of the ice-making device of the refrigerator illustrated in FIG. 1.

FIG. 7 is a side sectional view illustrating the configuration of an exemplary ice-making device according to another embodiment of the present invention.

FIG. 8 is an operation state view illustrating an exemplary method of sensing ice level sensed by an ice level sensing unit of the ice-making device illustrated in FIG. 7.

FIG. 9 is an operation state view illustrating another exemplary method of sensing ice level by an ice level sensing unit of the ice-making device illustrated in FIG. 7.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here.

One or more exemplary embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings, in which one or more exemplary embodiments of the disclosure can be easily determined by those skilled in the art. As those skilled in the art will realize, the described exemplary embodiments may be modified in various different ways, all without departing from the spirit or scope of the present disclosure, which is not limited to the exemplary embodiments described herein.

It is noted that the drawings are schematic and are not necessarily dimensionally illustrated. Relative sizes and proportions of parts in the drawings may be exaggerated or reduced in size, and a predetermined size is merely exemplary and not limiting. The same reference numerals designate the same structures, elements, or parts illustrated in two or more drawings in order to exhibit similar characteristics.

The exemplary drawings of the present disclosure illustrate ideal exemplary embodiments of the present disclosure in more detail. As a result, various modifications of the drawings are expected. Accordingly, the exemplary embodiments are not limited to a specific form of the illustrated region, and for example, include a modification of a form due to manufacturing.

Preferred embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view illustrating the configuration of an exemplary refrigerator according to one embodiment of the present disclosure. FIG. 2 is a side view of the exemplary refrigerator illustrated in FIG. 1.

Referring to FIGS. 1 and 2, the refrigerator 1 according to one embodiment of the present disclosure may include: a main body 100 defining an outer body or housing of the refrigerator and including a storage space; a barrier B configured to divide the storage space formed within the main body 100 into an upper refrigeration compartment R and a lower freezer F; doors 200 including a refrigeration compartment door 210 of the refrigeration compartment R through rotational movement and a freezer door 220 of the freezer F; an ice-making compartment 300 in the refrigeration compartment door 210 or the freezer door 220; and an ice-making device 400 in the ice-making compartment 300 and configured to produce ice pieces using cold air.

The ice-making compartment 300 may receive cold air generated through repeated cycles of compression, condensation, expansion and evaporation of a refrigerant. More specifically, a gaseous refrigerant having low temperature and low pressure is compressed by a compressor 2 into a gaseous state having high temperature and high pressure. The gaseous refrigerant having high temperature and high pressure is condensed by a condenser 3 into a liquid state having high temperature and high pressure. In an expander (not shown), the liquid refrigerant having high temperature and high pressure is expanded into a liquid refrigerant having low temperature and low pressure. Then, the liquid refrigerant having low temperature and low pressure is fed to an evaporator 4. In the evaporator 4, the liquid refrigerant having low temperature and low pressure is evaporated by absorbing heat from ambient air, thereby converting ambient air into cold air for supply to the storage spaces. The ice-making device 400 in the ice-making compartment 300 may produce ice pieces using cold air thus generated.

Hereinafter, the exemplary ice-making device 400 is described with reference to FIGS. 3 to 5.

FIG. 3 is an exploded perspective view illustrating the configuration of an exemplary ice-making device of the refrigerator illustrated in FIG. 1. FIG. 4 is a side sectional view illustrating the configuration of exemplary ice-making device of the refrigerator illustrated in FIG. 1. FIG. 5 is a front view illustrating the configuration of the exemplary ice-making device of the refrigerator illustrated in FIG. 1. The side surface illustrated in FIG. 4 is a side surface opposite to the side surface illustrated in FIG. 2.

Referring to FIGS. 1 to 5, the ice-making device 400 may include an ice-making assembly 410 configured to produce ice pieces, an ice bucket 420 configured to store ice pieces produced in the ice-making assembly 410, an ice level sensing unit 430 configured to sense the level, amount or fullness of the ice pieces in the ice bucket 420 and located lower than an upper edge A of the ice bucket 420.

The ice-making assembly 410 may include an ice tray 412 configured to accommodate water and to produce ice pieces, a cold air flow path 414 configured to guide cold from the cold air duct 110 to move along a lower surface of the ice tray 412, and a rotary unit (not shown) configured to rotate the ice tray 412 to release the ice pieces into the ice bucket 420.

The ice tray 412 may include ice cells 413 for receiving water from a water supply port 405. The ice cells 413 may have different shapes or numbers in different embodiments.

The ice tray 412 may be made of metal, for example, aluminum, having high heat conductivity. Thus, the ice tray 412 functions as a heat exchanger.

Under the ice tray 412, there may be disposed cold air flow path 414 for cold air supplied from the cold air duct 110. Due to heat exchange between cold air and the ice tray 412, water accommodated within the ice cells 413 of the ice tray 412 freezes into ice pieces.

The ice pieces thus produced may be stored in the ice bucket 420 disposed under the ice tray 412. For this purpose, the ice bucket 420 may include a first sidewall 422 and a second sidewall 424 facing each other.

A first cutout portion 423 is disposed in the first sidewall 422, through which light emitted from a light-emitting sensor 432 can pass.

A second cutout portion 425 is disposed in the second sidewall 422, through which the light emitted from the light-emitting sensor 432 can pass. Light emitted from the light-emitting sensor 432 is irradiated toward a light-receiving sensor 434.

In the related art, to sense the fullness of ice pieces in the ice bucket 420, an ice level sensing unit is disposed in a position equal to higher than an upper edge A of the ice bucket 420. However, as the level of the ice pieces filled in the ice bucket 420 grows higher, the sensing accuracy decreases. When a user removes the ice bucket 420, the ice pieces stored in the ice bucket 420 can spill over.

The ice level sensing unit 430 according to one embodiment of the present disclosure may be positioned in a position B lower than the upper edge A of the ice bucket 420 and may sense the level of the ice pieces stored in the ice bucket 420.

For this purpose, the ice level sensing unit 430 may include: a light-emitting sensor 432 installed on one sidewall 310 of the ice-making compartment 300 and configured to emit light; and a light-receiving sensor 434 installed on the other sidewall 320 of the ice-making compartment 300 to face the light-emitting sensor 432 and configured to sense the light emitted from the light-emitting sensor 432.

The light-emitting sensor 432 may be installed on one sidewall 310 of the ice-making compartment 300 and may continuously or periodically emit light that can be blocked by the ice pieces stored in the ice bucket 420.

Since the light-emitting sensor 432 may be installed on one sidewall 310 of the ice-making compartment 300, the position of the light-emitting sensor 432 would not be changed by vibration of any component in the ice-making compartment 300, e.g., vibration caused during removal of the ice bucket 420. Thereby, the level and/or fullness of ice pieces in the ice bucket 420 can be sensed in a reliable, consistent and accurate manner.

The light-receiving sensor 434 may be installed on the other sidewall 320 of the ice-making compartment 300 to face the light-emitting sensor 432 so that a straight light path is formed between the light-emitting sensor 432 and the light-receiving sensor 434.

Since the light-receiving sensor 434 may be installed on the other sidewall 320 of the ice-making compartment 300, the position of the light-receiving sensor 434 would not be changed by vibration of any component in the ice-making compartment 300.

As described above, the first cutout portion 423 and the second cutout portion 425, through which light emitted from the light-emitting sensor 432 can pass, are formed in the first sidewall 422 and the second sidewall 424 of the ice bucket 420. Thus, light emitted from the light-emitting sensor 432 may be transmitted to the light-receiving sensor 434 through the first cutout portion 423 and the second cutout portion 425. For example, transparent windows (not shown) may be disposed in the first cutout portion 423 and the second cutout portion 425 to prevent ice pieces from falling out through the first cutout portion 423 and the second cutout portion 425 while at the same time allowing passage of light emitted from the light-emitting sensor 432. However, this implementation is merely exemplary. The present disclosure is not necessarily limited thereto.

As illustrated in FIG. 5, the light-emitting sensor 432 and the light-receiving sensor 434 may be located on one sidewall 310 and the other sidewall 320 of the ice-making compartment 300 at a position B spaced apart downward by a predetermined distance d from the upper surface A of the ice bucket 420. This allows the ice fullness level sensed by the ice level sensing unit 430 to be adjustable. Moreover, the ice level sensing level may be adjusted by changing the predetermined distance d. For example, the detectable level may become higher as the value of the predetermined distance d grows smaller. The ice level sensing level may become lower as the value of the predetermined distance d increases.

The light-emitting sensor 432 and the light-receiving sensor 434 may be spaced apart in the transverse direction of the ice bucket 420. Thus, compared with a case where the light-emitting sensor 432 and the light-receiving sensor 434 are spaced apart in the longitudinal direction of the ice bucket 420, the distance between the light-emitting sensor 432 and the light-receiving sensor 434 is reduced. This can advantageously reduce or prevent assembly error. In this regard, the transverse direction of the ice bucket 420 refers to an X-axis direction in FIG. 4 and the longitudinal direction of the ice bucket 420 refers to a Z-axis direction in FIG. 4.

The control unit 500 may determine the fullness of ice pieces in the ice bucket 420 depending on the amount of light sensed by the light-receiving sensor 434. The operation or non-operation state of the ice-making device 400 may be determined based on the determination by the control unit 500. The method of determining the fullness of ice pieces in the ice bucket 420 using the control unit 500 and the method of operating the ice-making device 400 using the control unit 500 are described in greater detail below.

The operation and effect of the ice-making device 400 configured as above are described with reference to FIG. 6. FIG. 6 is an operation state view illustrating an exemplary method of sensing the ice level or the ice fullness using the ice level sensing unit of the ice-making device of the refrigerator illustrated in FIG. 1.

Cold air generated through the compressor, the condenser, the expander and the evaporator may be supplied to the ice-making compartment 300 via the cold air duct 110. Since the cold air flow path 414 is coupled to and extends from the cold air duct 110, cold air flowing out from the cold air duct 110 enters the cold air flow path 414.

More specifically, cold air may exchange heat with the ice tray 412 while flowing through the lower surface of the ice tray 412. Thus, water contained in the ice tray 412 may freeze ice pieces which are then stored and stacked in the ice bucket 420 disposed under the ice tray 412.

As the level of the ice piece stack in the ice bucket 420 exceeds a predetermined level, the ice level sensing unit 430 may determine whether the capacity of the ice bucket 420 has been reached. If so, a fullness status is declared for the ice bucket.

More specifically, if the height of the ice piece stack in the ice bucket 420 is at or above a predetermined height, light continuously or periodically emitted from the light-emitting sensor 432 can be blocked by the ice pieces and cannot be received by the light-receiving sensor 434. If the amount of the light sensed by the light-receiving sensor 434 reduces significantly and becomes lower than a threshold, the control unit 500 may determine that ice bucket 420 is full and may stop the operation of the ice-making device 400.

Since the light-emitting sensor 432 and the light-receiving sensor 434 according to one embodiment of the present disclosure are installed in a position B that is lower than the upper edge A of the ice bucket 420, the ice level can be detected even if the ice bucket is less than completely full. This enables sensing in advance regarding the fullness of ice pieces in the ice bucket 420 before the ice pieces are stacked up to the upper edge A of the ice bucket 420. Advantageously, spilling or overflow of ice pieces from the ice bucket can be prevented.

On the other hand, if the level of the ice piece stack in the ice bucket 420 lowers, e.g., after dispensing to a user, the space between the light-emitting sensor 432 and the light-receiving sensor 434 eventually becomes unblocked again. Thus, the amount of light emitted from the light-emitting sensor 432 and received by the light-receiving sensor 434 increases. Accordingly, at some point, the control unit 500 determines that the amount of ice stored in the ice bucket 420 reaches a lower threshold and thereby reactivates the ice-making device 400.

Ice pieces stored in the ice bucket 420 can be delivered to an ice-breaking unit 700 by an auger 600. The ice pieces may be broken by a rotatable blade (not shown) and a fixed blade (not shown) and are then supplied to a user.

As described above, the light-emitting sensor 432 and the light-receiving sensor 434 of the ice level sensing unit 430 according to one embodiment of the present disclosure are installed on sidewalls 310 of the ice-making compartment 300. In this configuration, a level that can be sensed would not change due to any vibration related to the ice-making compartment, because the light-emitting sensor 432 and the light-receiving sensor 434 are fixed to the sidewalls 310 and 320 of the ice-making compartment 300. Thereby, the level and/or fullness of ice pieces in the ice bucket 420 can be advantageously sensed in a reliable, consistent and accurate manner.

Furthermore, the light-emitting sensor 432 and the light-receiving sensor 434 are spaced apart from electrical components such as an ice-releasing heater (not shown), an auger drive motor (not shown) and the like. This can advantageously prevent damage to the light-emitting sensor 432 and the light-receiving sensor 434 caused by the electrical components, where the damage would adversely affect the sensing accuracy of the ice level sensing unit.

Moreover, according to the present disclosure, a light sensor is used to detect ice level or fullness in an ice bucket, rather than a complicated mechanical sensor in the conventional art. This can advantageously reduce the number of required components, simplify assembly procedure and reduce manufacturing cost.

To enlarge a sensing range, the ice level sensing unit 430 may include a plurality of light-emitting sensors 432′ and a plurality of light-receiving sensors 434′. The number of the light-emitting sensors 432′ and the number of the light-receiving sensors 434′ may both be n (where n is greater than 2).

Hereinafter, an ice-making device 401 according to another embodiment of the present disclosure is described with reference to FIGS. 7 to 9. FIG. 7 is a side sectional view illustrating the configuration of an exemplary ice-making device according to another embodiment of the present invention. FIG. 8 is an operation state view illustrating an exemplary method of sensing an ice level by using the ice level sensing unit illustrated in FIG. 7. FIG. 9 is an operation state view illustrating another exemplary method of sensing ice level by using the ice level sensing unit illustrated in FIG. 7.

The light-emitting sensors 432′ and the light-receiving sensors 434′ may be installed the sidewalls 310 and 320 of the ice-making compartment 300. In this case, the light emitted from the light-emitting sensors 432′ may be sensed by the light-receiving sensors 434′. This can advantageously enlarge a sensing region by an ice level sensing unit 431.

More specifically, the light-emitting sensors 432′ may include a first light-emitting sensor 432a disposed at the left side of the sidewall 310 of the ice-making compartment 300 on the basis of the X-axis in FIG. 7 and a second light-emitting sensor 432b disposed at the right side of the sidewall 310 of the ice-making compartment 300 on the basis of the X-axis in FIG. 7.

Furthermore, the light-receiving sensors 434′ may include a first light-receiving sensor 434a disposed at the left sidewall 320 of the ice-making compartment 300 and a second light-receiving sensor 434b disposed at the right sidewall 320 of the ice-making compartment 300.

As illustrated in FIG. 8, the control unit 500 controls the first light-emitting sensor 432a and the second light-emitting sensor 432b to emit light toward the first light-receiving sensor 434a and the second light-receiving sensor 434b. In other words, among the light-emitting sensors 432′ and the light-receiving sensors 434′, the first light-emitting sensor 432a and the first light-receiving sensor 434a disposed at the same level form a pair for sensing. The second light-emitting sensor 432b and the second light-receiving sensor 434b disposed at the same level forms another pair for sensing.

More specifically, light emitted from the first light-emitting sensor 432a disposed at the left sidewall 310 of the ice-making compartment 300 is transmitted to the first light-receiving sensor 434a disposed at the left sidewall 320 thereof. The light emitted from the second light-emitting sensor 432b disposed at the right sidewall 310 is transmitted to the second light-receiving sensor 434b disposed at the right sidewall 320.

Due to this configuration, the ice level sensing region is enlarged, because the light-emitting sensors 432′ and the light-receiving sensors 434′ are provided in a plural number. However, it might be difficult to sense the ice pieces positioned in the space between the left and right sides of one sidewall 310 of the ice-making compartment 300 and in the space between the left and right sides of the other sidewall 320 of the ice-making compartment 300.

Thus, as illustrated in FIG. 9, the control unit 500 may control the first light-emitting sensor 432a to emit light toward the second light-receiving sensor 434b. Furthermore, the control unit 500 may control the second light-emitting sensor 432b to emit light toward the first light-receiving sensor 434a. In other words, among the light-emitting sensors 432′ and the light-receiving sensors 434′, the first light-emitting sensor 432a and the second light-receiving sensor 434b disposed at different levels form a pair to perform an ice fullness sensing operation. The second light-emitting sensor 432b and the first light-receiving sensor 434a disposed at different levels form a pair to perform an ice fullness sensing operation.

The control unit 500 controls the first light-emitting sensor 432a and the second light-emitting sensor 432b so that the first light-emitting sensor 432a and the second light-emitting sensor 432b alternately flicker at a predetermined time interval. This enables the first light-emitting sensor 432a and the second light-emitting sensor 432b to emit light toward the second light-receiving sensor 434b and the first light-receiving sensor 434a without light interference. Thus, the ice level sensing region (in which the ice level can be sensed) is further widened. It is therefore possible to eliminate a source of an erroneous operation attributable to ice level sensing errors. This makes it possible to improve the reliability and quality of the ice-making device 401.

From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. The exemplary embodiments disclosed in the specification of the present disclosure do not limit the present disclosure. The scope of the present disclosure will be interpreted by the claims below, and it will be construed that all techniques within the scope equivalent thereto belong to the scope of the present disclosure.

Claims

1. A refrigerator comprising:

an ice-making compartment; and

an ice-making device disposed inside the ice-making compartment and comprising: an ice-making assembly configured to produce ice from water; an ice bucket configured to store the ice produced in the ice-making assembly; and an ice level sensing unit configured to sense a level of ice in the ice bucket, wherein the ice level sensing unit is disposed lower than an upper edge of the ice bucket.

2. A refrigerator of claim 1 further comprising:

a main body comprising a storage space; and

a door coupled to the main body for covering the storage space, and

wherein the ice-making compartment is disposed in the door or inside the main body.

3. A refrigerator of claim 1, wherein the ice level sensing unit comprises:

a light-emitting sensor installed on one sidewall of the ice-making compartment and configured to emit light; and

a light-receiving sensor installed on the other sidewall of the ice-making compartment and configured to receive light emitted from the light-emitting sensor.

4. The refrigerator of claim 3, wherein the ice bucket comprises:

a first sidewall comprising a first cutout portion, wherein light emitted from the light-emitting sensor is transmitted to the light-receiving sensor through the first cutout portion; and

a second sidewall facing the first sidewall of the ice bucket and comprising a second cutout portion, wherein light emitted from the light-emitting sensor is transmitted to the light-receiving sensor through the second cutout portion.

5. The refrigerator of claim 3, wherein the light-emitting sensor and the light-receiving sensor are spaced apart in a transverse direction of the ice bucket.

6. The refrigerator of claim 3 further comprising a control unit configured to determine fullness of the ice bucket based on a detected level of ice in the ice bucket.

7. The refrigerator of claim 6, wherein a level of ice in the ice bucket is determined based on an amount of light sensed by the light-receiving sensor.

8. A refrigerator comprising:

an ice-making compartment;

an ice tray disposed within the ice-making compartment and configured to receive water and to produce ice from the water;

an ice bucket configured to store the ice produced in the ice tray;

an ice level sensing unit configured to detect an ice level in the ice bucket and the ice level sensing unit comprising: a light-emitting unit installed on a first wall of the ice-making compartment; and a light-receiving unit installed on a second wall of the ice-making compartment.

9. The refrigerator of claim 8, wherein the light-emitting unit is disposed in a position lower than an upper edge of the ice bucket.

10. The refrigerator of claim 9, wherein the light-emitting unit comprises a plurality of light-emitting sensors configured to emit light.

11. The refrigerator of claim 10, wherein the light-receiving unit is disposed in a position lower than the upper edge of the ice bucket.

12. The refrigerator of claim 11, wherein the light-receiving unit comprises a plurality of light-receiving sensors configured to sense the light emitted from the light-emitting unit.

13. The refrigerator of claim 10, further comprising:

a control unit configured to cause the light-emitting sensors to alternately emit light.

14. The refrigerator of claim 12, wherein a light-receiving sensor and a light-emitting sensor are disposed at a same height with reference to the ice bucket.

15. The refrigerator of claim 12, wherein a light-receiving sensor and a light-emitting sensor are disposed at different heights with reference to the ice bucket.

16. The refrigerator of claim 13, wherein the control unit is configured to determine fullness of the ice bucket based on an ice level detected by the ice level sensing unit.