Patent Publication Number: US-10323871-B2

Title: Method for diagnosing ice-making apparatus

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Korean Patent Application No. 10-2016-0167260, filed on Dec. 9, 2016, the entire contents of which is incorporated herein for all purposes by this reference. 
     BACKGROUND 
     Field of the Present Disclosure 
     The present disclosure relates to a method for diagnosing an ice-making apparatus, and more particularly, to a method for determining an abnormality of an ice-making apparatus. 
     Discussion of Related Art 
     The ice-making apparatus cools water to produce ice, and may be classified into residential and commercial types. The ice-making apparatus performs an ice forming and removing cycles at regular intervals. 
     In the event of an abnormality of the ice-making apparatus, it is important to check an abnormal state of the ice forming and removing cycle. In particular, it is further important to determine whether the ice-making apparatus is performing the ice forming and removing cycle in a normal state after inspection and repair thereof due to the abnormality of the ice-making apparatus. 
     It should be understood that the foregoing description in this background section is merely for the purpose of promoting an understanding of the background of the present disclosure and is not to be construed as an admission that the foregoing description is considered as a prior art as known to those skilled in the art. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify all key features or essential features of the claimed subject matter, nor is it intended to be used alone as an aid in determining the scope of the claimed subject matter. 
     The present disclosure is to provide a method for diagnosing an ice-making apparatus to effectively determine whether the ice-making apparatus is operating normally. 
     In a first aspect of the present disclosure, there is provided a method for diagnosing an ice-making apparatus, wherein the ice-making apparatus includes a control unit and a display unit, wherein the method comprises: determining, by the control unit, whether a diagnosis-initiation condition for the ice-making apparatus is satisfied or not; upon determination that the diagnosis-initiation condition for the ice-making apparatus is satisfied, counting, by the control unit, an actual number of ice forming and removing cycles performed by the ice-making apparatus; and displaying the counted number on the display unit by the control unit. 
     In one implementation, determining, by the control unit, whether a diagnosis-initiation condition for the ice-making apparatus is satisfied or not comprises determining, by the control unit, that the diagnosis-initiation condition for the ice-making apparatus is satisfied in an event that an inspection mode in which the ice-making apparatus is disassembled and assembled is terminated. 
     In one implementation, the ice-making apparatus includes a manipulation interface, wherein determining, by the control unit, whether a diagnosis-initiation condition for the ice-making apparatus is satisfied or not comprises determining, by the control unit, that the diagnosis-initiation condition for the ice-making apparatus is satisfied in an event that a diagnosis-trigger button on a manipulation interface is activated. 
     In one implementation, the ice-making apparatus includes a hot-gas valve, wherein counting, by the control unit, the number of ice forming and removing cycles performed by the ice-making apparatus comprises counting, by the control unit, the number of opening the hot-gas valve in ice-removing operations of the ice forming and removing cycles. 
     In one implementation, counting, by the control unit, the number of ice forming and removing cycles performed by the ice-making apparatus further comprises counting a time elapse between a start time to counter the number of ice forming and removing cycles performed by the ice-making apparatus and a current time. 
     In one implementation, the method further includes: calculating, by the control unit, a normal expected range of a number of ice forming and removing cycles for the time elapse, wherein the normal expected range is defined by a normal expected number of ice forming and removing cycles in a normal state of the ice-making apparatus for the time elapse and a first predetermined tolerance; and determining whether the actual number of ice forming and removing cycles performed by the ice-making apparatus is in the normal expected range, thereby to determine whether the ice-making apparatus is in a normal or abnormal state based on the determination, wherein displaying the counted number on the display unit by the control unit further comprises displaying the determination result of the normal or abnormal state of the apparatus on the display unit by the control unit. 
     In one implementation, counting, by the control unit, the number of ice forming and removing cycles performed by the ice-making apparatus further comprises counting, by the control unit, an actual cycle time of each of the ice forming and removing cycles performed by the ice-making apparatus, wherein the method further comprises: determining whether each actual cycle time of each of the ice forming and removing cycles is in a range of a normal expected cycle time range corresponding to a single ice forming and removing cycle, wherein the normal expected cycle time range is associated with a normal state of the apparatus; computing a number of the ice forming and removing cycles having the actual cycle times not being in the range of the normal expected cycle time range respectively; and determining whether the computed number exceeds a predetermined value, thereby to determine whether the ice-making apparatus is in a normal or abnormal state based on the determination. 
     In a second aspect of the present disclosure, there is provided a computer-readable storage medium having stored thereon a computer program comprising instructions, wherein the instructions, when executed by one or more processors of a computer device, causes the one or more processors to perform operations of a method for diagnosing an ice-making apparatus, wherein the ice-making apparatus includes a display unit, wherein the operations comprises: determining whether a diagnosis-initiation condition for the ice-making apparatus is satisfied or not; upon determination that the diagnosis-initiation condition for the ice-making apparatus is satisfied, counting an actual number of ice forming and removing cycles performed by the ice-making apparatus; and displaying the counted number on the display unit. 
     According to embodiments of the present invention, the normal or abnormal operating state of the ice-making apparatus can be grasped simply and effectively. 
     According to embodiments of the present invention, the actual number of ice forming and removing cycles and the elapsed time are displayed on the display unit, so that the operator can efficiently determine whether the ice forming and removing cycle is normally performed. 
     According to embodiments of the present invention, by measuring the number of times of opening the hot-gas valve and, thus, the number of the ice forming and removing cycle, it is possible to accurately and effectively determine the operation state of the apparatus based on the number of the ice forming and removing cycle. 
     According to embodiments of the present invention, by analyzing the number of ice forming and removing cycles together with the actual cycle time of each of the ice forming and removing cycles, the operating state analysis of the ice-making apparatus may be made more reliably. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a flow diagram illustrating a method for diagnosing an ice-making apparatus according to an embodiment of the present invention; 
         FIG. 2  is a view illustrating a manipulation interface and a display unit provided on an ice-making apparatus in association with a method for diagnosing an ice-making apparatus according to an embodiment of the present invention; and 
         FIG. 3  is a schematic diagram of a system for diagnosing an ice-making apparatus according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTIONS 
     Examples of various embodiments are illustrated and described further below. It will be understood that the description herein is not intended to limit the claims to the specific embodiments described. On the contrary, it is intended to cover plate alternatives, modifications, and equivalents as may be included within the spirit and scope of the present disclosure as defined by the appended claims. 
     Further, descriptions and details of well-known steps and elements are omitted for simplicity of the description. Furthermore, in the following detailed description of the present disclosure, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be understood that the present disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the present disclosure. 
     It will be understood that, although the terms “first”, “second”, “third”, and so on may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section described below could be termed a second element, component, region, layer or section, without departing from the spirit and scope of the present disclosure. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “includes”, and “including” when used in this specification, specify the presence of the stated features, integers, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, operations, elements, components, and/or portions thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expression such as “at least one of” when preceding a list of elements may modify the entire list of elements and may not modify the individual elements of the list. 
     Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this inventive concept belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     As used herein, terms “unit” and “module” refer to means that processes at least one function or operation, and may be implemented in hardware, software, or a combination thereof. 
     In embodiments of the present invention, each component, function block or means may include one or more sub-components, function sub-blocks, or sub-means. Electrical and electronic functions performed by each component may be implemented with well-known electronic circuits, integrated circuits, or ASICs (Application Specific Integrated Circuits), or the like. The electrical and electronic functions may be implemented separately or in a combination thereof. 
     Further, each block of the accompanying block diagrams, and each step of the accompanying flowchart may be performed by computer program instructions. These computer program instructions may be embedded within a processor of a general purpose computer, a special purpose computer, or other programmable data processing devices. Thus, the instructions when executed by the processor of the computer or other programmable data processing device will generate means for performing a function described in each block of the block diagram or each step of the flow chart. 
     These computer program instructions may be stored in a computer usable or computer readable memory coupled to the computer or other programmable data processing device to implement the functions in a particular manner. As such, the instructions stored in such a computer-usable or computer-readable memory enable the production of articles with instruction means that perform a function described in each block of the block diagram or each step of the flow chart. 
     Referring to  FIG. 1  to  FIG. 3 , an ice-making apparatus  100  includes a control unit  150  and a display unit  103 . A method for diagnosing an ice-making apparatus comprises: determining, by the control unit  150 , whether a diagnosis-initiation condition for the ice-making apparatus is satisfied or not S 100 ; upon determination that the diagnosis-initiation condition for the ice-making apparatus  100  is satisfied, counting, by the control unit  150 , the number of ice forming and removing cycles performed by the ice-making apparatus  100  S 200 ; and displaying the counted number on the display unit  103  by the control unit  150  S 400 . 
     More specifically, in the diagnosis-initiation condition determination operation S 100 , the control unit  150  may be configured to determine whether a diagnosis-initiation condition for the ice-making apparatus  100  is satisfied or not. 
     In embodiments, before a diagnosis for the ice-making apparatus  100  is performed, the control unit  150  determines whether the ice-making apparatus  100  currently meets a condition for triggering the diagnosis for the ice-making apparatus  100 . In this connection, the diagnosis-initiation condition may vary. 
     In one embodiment, in an event that the ice-making apparatus  100  is powered off for inspection and repair thereof, and then is powered on again, and thus an ice forming and removing cycle thereof starts, the control unit  150  determines that the diagnosis-initiation condition for the ice-making apparatus  100  is met. In another embodiment, in an event that a diagnosis-trigger button on a manipulation interface  105  provided on the ice-making apparatus  100  is activated, the control unit  150  determines that the diagnosis-initiation condition for the ice-making apparatus  100  is met. 
     As used herein, the diagnosis is to determine if the ice forming and removing cycle operates normally, in embodiments, whether the ice forming and removing cycle is being performed as designed. In a situation where an abnormal state of the ice-making apparatus  100  is suspected, the diagnosis according to embodiments of the present invention may be required. Further, when the abnormal state of the ice-making apparatus  100  is confirmed, and thereafter, it has checked and repaired, the diagnosis according to embodiments of the present invention may be required to determine whether or not the ice-making apparatus  100  has returned to the normal state. 
     As for the counting operation S 200 , upon determination that the diagnosis-initiation condition for the ice-making apparatus  100  is satisfied, the control unit  150  may be configured to count the number of ice forming and removing cycles performed by the ice-making apparatus  100 . In this connection, each of the ice forming and removing cycles includes an ice-forming operation an ice-removing operation. 
     In the ice-forming operation, water on a cold plate is cooled to produce ice. In the ice-removing operation, the generated ice is removed from the cold plate. 
     The ice-making apparatus  100  includes a cooling system using a refrigerant. The cold plate is mounted on an evaporator of the cooling system. The ice-making apparatus  100  includes a water circulation system for supplying water to the cold plate. 
     In this way, the ice forming and removing cycles are performed in a predefined flow. In accordance with embodiments of the present invention, upon determination that the diagnosis-initiation condition for the ice-making apparatus  100  is satisfied, the control unit  150  counts the number of ice-forming and removing cycles for the ice-making apparatus  100  S 200 . 
     It may be recognized by the control unit  105  that a diagnosis start time corresponds to a time when it is confirmed that, in the diagnosis-initiation condition determination operation S 100 , the diagnosis-initiation condition of the ice-making apparatus  100  is satisfied. An end point of the diagnosis may not be set separately. Alternatively, the control unit  150  may recognize the diagnosis end point as a time point when the diagnosis-trigger button on the manipulation interface  105  is turned off. 
     In the displaying operation S 400 , the control unit  150  enables the display unit  103  to display thereon the counted number of ice forming and removing cycles performed by the ice-making apparatus  100 . The display unit  103  may be disposed on the manipulation interface  105 . However, the present invention is not limited thereto. 
     The counted number of ice forming and removing cycles performed by the ice-making apparatus  100  may refer to the number of ice forming and removing cycles performed by the ice-making apparatus  100  until a current time. The number of ice forming and removing cycles performed by the ice-making apparatus  100  may be used to determine the normal or abnormal state of the ice-making apparatus  100  in various manners. 
     In one embodiment, when the end point of the diagnosis is not set separately, the user or the control unit may determine a life span of the ice-making apparatus  100  based on the counted number of the ice forming and removing cycles displayed on the display unit  103 . 
     Further, the user or the control unit  105  may determine an abnormality state of the ice-making apparatus  100  based on the counted number of ice forming and removing cycles performed by the ice-making apparatus  100 . In one embodiment, when the abnormality of the ice-making apparatus  100  is suspected and thus, the diagnosis-trigger button on the manipulation interface  105  is activated by the user, the user or the control unit  105  may determine whether the number of ice-forming and removing cycles performed by the ice-making apparatus  100  from the start time of diagnosis to a current time is normal. 
     More specifically, an elapsed time from the start of diagnosis to the current time is counted. A time taken to perform a single ice forming and removing cycle as preset for the ice-making apparatus  100  is considered. In this way, in the normal state, a normal expected number of ice forming and removing cycles from the diagnosis start to the current time may be derived. This normal expected number is compared with the actual number of ice forming and removing cycles, as which is indicated on the display unit  103 . Based on the comparison result, the abnormal state of the ice-making apparatus  100  can be determined. 
     The method for diagnosing the ice-making apparatus  100  according to embodiments of the present invention may be particularly useful after the inspection and repair of the ice-making apparatus  100 . Once the failure of the ice-making apparatus  100  is identified, an internal configuration of the ice-making apparatus  100  is inspected and repaired. 
     When the internal configuration of the ice-making apparatus  100  has been inspected and repaired, in embodiments, it may be necessary to determine whether the repair of the ice-making apparatus  100  is successful. In this case, the method for diagnosing the ice-making apparatus  100  according to embodiments of the present invention may be used to determine whether the repair of the ice-making apparatus  100  is successful. 
     In one embodiment, when the internal configuration of the ice-making apparatus  100  has been inspected and repaired and the ice-making apparatus  100  starts to operate, the control unit  150  may count the actual number of ice forming and removing cycles performed by the ice-making apparatus  100  and may enable the display unit  103  to display thereon the actual number. An operator may measure an elapsed time from the start time to the current time, and calculate a normal expected number of ice forming and removing cycles from the start time to the current time based on the elapsed time. The operator may compare this normal expected number with the actual number of ice forming and removing cycles, as which is indicated on the display unit  103 . 
     When the actual number of ice forming and removing cycles is different from the normal expected number thereof, it may be determined that the ice-making apparatus  100  is in an abnormal state. This means that the inspection and repair for the ice-making apparatus  100  is not successful. 
     Otherwise, when the actual number of ice forming and removing cycles match the normal expected number thereof, it may be determined that the ice-making apparatus  100  is in a normal state. This means that the inspection and repair for the ice-making apparatus  100  is successful. Thus, reliability of the maintenance and inspection of the ice-making apparatus  100  can be improved. 
     Further, while the diagnosis of the ice forming and removing cycle is being performed, the operator may perform other tasks. This allows time-efficient maintenance and inspection of the ice-making apparatus  100 . 
     According to embodiments of the present invention, the control unit  150  diagnoses an abnormality of the ice-making apparatus  100 , in particular, using the counted number of ice forming and removing cycles performed by the ice-making apparatus  100 . This is due to the fact that the abnormality of the ice-making apparatus ultimately affects the time required for the ice forming and removing cycles. 
     For example, if there is a problem on the water circulation system, the water will not be able to flow smoothly to the cold plate. This can increase the time required for the ice forming and removing cycles. Further, even if there is a problem with the cooling system, the temperature of the cold plate does not reach the preset temperature. This leads to an increase in the time required for the ice forming and removing cycles. 
     Furthermore, if the ice-making apparatus  100  has an inoperability, this may also lead to an increase in the time required for the ice forming and removing cycles. Therefore, in accordance with embodiments of the present invention, the control unit  150  may be configured to diagnose the abnormality of the ice-making apparatus  100 , particularly on the basis of the time required for the ice forming and removing cycle or the actual counted number of ice forming and removing cycles. 
     In embodiments of the present invention, the time required for the ice forming and removing cycles is used as a measure indicating the abnormality of the ice-making apparatus  100 . When the diagnosis-initiation condition is satisfied, the ice-making apparatus  100  starts operating. The number of ice forming and removing cycles performed by the ice-making apparatus  100  is measured by the control unit  150  and then displayed on the display unit  103 . Thereby, the inspector, the user or the control unit can simply and effectively diagnose whether or not the ice-making apparatus  100  is in a normal state. 
       FIG. 1  is a flowchart illustrating a method for diagnosing the ice-making apparatus  100  according to embodiments of the present invention.  FIG. 2  shows the ice-making apparatus  100  provided with the manipulation interface  105  and the display unit  103  as described above. The manipulation interface  105  and the display unit  103  will be described in detail later. 
       FIG. 3  is a diagram illustrating a system for diagnosing the ice-making apparatus  100  according to embodiments of the present invention. In  FIG. 3 , the cooling system and the water circulation system are schematically shown, and the control unit  150  is also shown. 
     Referring to  FIG. 1 , the method for diagnosing the ice-making apparatus  100  may include the diagnosis-initiation condition determination operation S 100 . In one embodiment, determining, by the control unit  150 , whether the diagnosis-initiation condition for the ice-making apparatus  100  is satisfied or not may comprise determining, by the control unit  150 , that the diagnosis-initiation condition for the ice-making apparatus  100  is satisfied in an event that an inspection mode in which the ice-making apparatus  100  is disassembled and assembled is terminated. 
     In one embodiment, the control unit  150  may recognize a situation in which the power of the ice-making apparatus  100  is shut off and then powered back, as the inspection mode termination event. In another embodiment, the control unit  150  may recognize a situation in which the abnormality of the ice-making apparatus  100  has previously been determined, and, thus, the ice-making apparatus  100  is powered off and then back on, as the inspection mode termination event. 
     In one embodiment, the manipulation interface  105  may include an inspection button for checking and repairing the ice-making apparatus  100 . In this case, when the inspection button is activated, the control unit  150  may recognize the inspection button activation as an inspection mode activation event. Then, when the inspection button is deactivated, the control unit  150  may recognize this as the inspection mode termination event. This inspection mode termination event may correspond to an event where the diagnosis-initiation condition is met. 
     According to an embodiment of the present invention, the control unit  150  may recognize the inspection mode termination event of the ice-making apparatus  100  as the event of the diagnosis-initiation condition being met. Thus, unnecessary diagnosis is not performed and diagnosis of the ice-making apparatus  100  may be efficiently performed. 
     In one embodiment, determining, by the control unit  150 , whether a diagnosis-initiation condition for the ice-making apparatus is satisfied or not may comprise determining, by the control unit  150 , that the diagnosis-initiation condition for the ice-making apparatus is satisfied in an event that a diagnosis-trigger button on the manipulation interface  105  is activated. 
     In one embodiment, the ice-making apparatus  100  includes the manipulation interface  105 . When the diagnosis-trigger button on the manipulation interface  105  is activated by the user or operator, the control unit  150  may be configured to determine that the diagnosis-initiation condition is met. 
     The manipulation interface  105  may be provided at various positions of the ice-making apparatus  100 . For example, the manipulation interface  105  may be provided inside the ice-making apparatus  100 . In this case, the manipulation interface  105  may be exposed and manipulated via disassembly of the ice-making apparatus  100 . In another embodiment, the manipulation interface  105  may be provided such that at least a portion of the manipulation interface  105  is exposed outside the ice-making apparatus  100 . The exposed portion of the manipulation interface  105  may be provided with a plurality of buttons that may be manipulated by the user or the examiner. More preferably, the display unit  103  may be positioned adjacent to the manipulation interface  105  or mounted on the manipulation interface  105 . In  FIG. 2 , the ice-making apparatus  100  is shown which is provided with the manipulation interface  105  and the display unit  103  as described above. 
     In an embodiment of the present invention, the control unit  150  may determine the diagnostic intent of the user or the inspector requesting diagnosis of the ice-making apparatus  100  based on the activation state of the diagnosis-trigger button of the manipulation interface  105 . Thus, unnecessary diagnosis is not performed, and the diagnosis of the ice-making apparatus  100  may be efficiently performed. 
     Referring to  FIG. 1  to  FIG. 3 , the method for diagnosing an ice-making apparatus according to an embodiment of the present invention includes the counting operation S 200 . In this connection, the control unit  150  counts the number of opening of the hot-gas valve  180  in the ice-removing operation of the ice forming and removing cycle, thereby to count the number of ice forming and removing cycles performed by the ice-making apparatus  100 . 
     In one embodiment, counting the number of ice forming and removing cycles performed by the ice-making apparatus  100  may include counting the number of the ice-removing operations performed by the ice-making apparatus  100 . 
     In the ice forming and removing cycle, the ice-forming operation may take more time than the ice-removing operation. Thus, it is not easy to configure a hardware-related control feature capable of specifying the ice-forming operation. 
     For example, during the ice-forming operation, water is supplied to the cold plate of the ice-making apparatus  100 . However, the supply of water continues to occur in the ice-forming operation. Thus, this supply of water may not be considered a typical feature to specify the ice-forming operation. 
     In the embodiment of the present invention, in consideration of the above, the number of times the hot-gas valve  180  is opened in the ice-removing operation of the ice forming and removing cycle is counted. The opening count of the hot-gas valve  180  may correspond to the number of the ice forming and removing cycles. The ice-making apparatus  100  according to embodiments of the present invention uses the hot gas to remove ice from the cold plate. 
     The hot gas is supplied from a compressor of the cooling system and then bypasses a condenser thereof. There is provided a hot gas flow channel for flowing the hot gas from the compressor to the evaporator equipped with the cold plate. The hot-gas valve  180  is provided in the hot gas flow channel. Such a configuration is shown in  FIG. 3 . 
     In order for the ice-removing operation to be performed, the hot-gas valve  180  is opened. The opening of the hot-gas valve  180  is controlled by the control unit  150 . In embodiments, the control unit  150  may count the number of times the hot-gas valve  180  is opened. Thus, the control unit  150  may determine the number of ice forming and removing cycles performed by the ice-making apparatus  100  based on the number of the opening of the valve  180 . 
     In one embodiment, the number of ice forming and removing cycles performed by the ice-making apparatus  100  may be measured based on the count of the opening of the hot-gas valve  180 . Thus, while the control unit  150  performs complicated control, the control unit may accurately calculate the number of ice forming and removing cycles performed by the ice-making apparatus  100 . 
     Referring to  FIG. 1 , the counting operation S 200  in the method for diagnosing an ice-making apparatus  100  may further include counting, by the control unit  150 , the time elapse between a start time to count the number of ice forming and removing cycles and a current time. 
     As described above, in accordance with embodiments of the present invention, the control unit  150  determines, based on the elapsed time, the normal expected number of the ice forming and removing cycles as pre-designed, and compares the normal expected number and the actual number of the ice forming and removing cycles as performed by the ice-making apparatus  100 , thereby diagnosing the abnormality of the ice-making apparatus  100  based on the comparison. 
     In an embodiment of the present invention, therefore, the elapsed time since the diagnosis has been performed may be counted by the control unit  150  in order to facilitate such diagnosis. It may be non-preferable for the user or the operator to calculate the elapsed time by himself or herself because the user or operator may mistake in determining the diagnosis start point. 
     Thus, in an embodiment of the present invention, the control unit  150  counts the elapsed time and diagnoses the ice-making apparatus  100  based on the elapsed time. The elapsed time may be variously used. 
     In one embodiment, the elapsed time may be displayed directly on the display unit  103 . Thereby, the user or the operator may be given convenience for confirming the diagnosis result. Furthermore, the control unit  150  will be able to determine the abnormal state of the apparatus  1  based on the elapsed time. This will be described below. 
     Referring to  FIG. 1  and  FIG. 2 , the method for diagnosing an ice-making apparatus may include a diagnosis operation S 300  subsequent to the counting operation S 200 . In the diagnosis operation S 300 , the control unit  150  may determine whether the number of ice forming and removing cycles performed by the ice-making apparatus  100  for the elapsed time is in a normal range. 
     In the displaying operation S 400 , the control unit  150  may enable the display unit  103  to display thereon the actual number of ice forming and removing cycles performed by the ice-making apparatus  100  and the diagnosis result of the ice-making apparatus  100 . 
     Specifically, the control unit  150  may analyze the number of ice forming and removing operations performed by the ice-making apparatus  100  based on the elapsed time. The diagnostic method based on this elapsed time may be various. In one embodiment of the present invention, the control unit  150  determines a normal expected number of ice forming and removing cycles in a normal state of the ice-making apparatus  100  based on the elapsed time. Thereafter, the control unit  150  compares the actual counted number of ice forming and removing cycles with the normal expected number of ice forming and removing cycles. 
     A single ice forming and removing cycle of the ice-making apparatus  100  may have a predetermined unit time. The normal expected number of the ice forming and removing cycles may be derived based on the predetermined unit time and the elapsed time to the current time. In an embodiment of the present invention, this normal expected number corresponds to the normal range of the number of ice forming and removing cycles. 
     In this connection, the normal range of the number of ice forming and removing cycles may further have a tolerance due to various factors. Thus, the normal range of the number of ice forming and removing cycles may not be exactly equal to the normal expected number but about the normal expected number due to the tolerance. The tolerance may be determined experimentally and/or statistically. 
     For example, depending on the cold plate temperature inside the evaporator of the ice-making apparatus  100 , the expected time required for the single ice forming and removing cycle may be slightly changed. Thus, the normal range may be determined with reflecting the tolerance due to the temperature change. 
     The control unit  150  determines whether the actual counted number of ice forming and removing cycles is in the normal expected range and, thereby, diagnoses an abnormality of the ice-making apparatus  100  based on the determination. If the actual counted number of ice forming and removing cycles is in the normal expected range, the control unit  150  may allow the display unit  103  to indicate that the ice-making apparatus  100  is in a normal state in the displaying operation S 400 . 
     Referring to  FIG. 1 , the method for diagnosing an ice-making apparatus may include the diagnosis operation S 300 . In the counting operation S 200 , the control unit  150  may measure the number of ice forming and removing cycles performed by the apparatus  1  until the current time and the time elapse between the start time of measuring the number and the current time. The diagnosis operation S 300  may include comparing, by the control unit  150 , the normal expected range of the ice forming and removing cycle and the actual measured number of the ice forming and removing cycles performed by the ice-making apparatus  100 ; and determine whether the actual number of ice forming and removing cycles performed by the ice-making apparatus  100  is in a range of the normal expected range, thereby to determine whether the ice-making apparatus  100  is in an abnormal state based on the determination. 
     In an embodiment of the present invention, the control unit determines the abnormal state of the ice-making apparatus  100  using each time spent for each ice forming and removing cycle as performed by the ice-making apparatus  100 , in addition to the total elapsed time for which the diagnosis was performed. 
     A normal cycle time required for a single ice forming and removing cycle as expected in the normal state of the ice-making apparatus  100  may be preset into the control unit  150 . In an embodiment of the present invention, the control unit counts the actual number of ice forming and removing cycles as performed by the ice-making apparatus  100 , and, concurrently, measures each actual cycle time spent for each ice forming and removing cycle as performed by the ice-making apparatus  100 . 
     In one embodiment, each cycle time spent for each ice forming and removing cycle as performed by the ice-making apparatus  100  may be obtained based on a start time point of each of the ice forming and removing cycles as performed by the ice-making apparatus  100 . In one embodiment, the start time point of each of the ice forming and removing cycles as performed by the ice-making apparatus  100  may correspond to an opening time of the hot-gas valve  180 . Thus, each time spent for each ice forming and removing cycle as performed by the ice-making apparatus  100  may be calculated as a time interval between previous and current opening times of the hot-gas valve  180   
     In this connection, due to various factors including variations in temperature of the cold plate, the normal cycle time required for a single ice forming and removing cycle as expected in the normal state of the ice-making apparatus  100  may have a time tolerance. Thus, each cycle time spent for each ice forming and removing cycle as performed by the ice-making apparatus  100  may be compared not to exactly the normal cycle time required for a single ice forming and removing cycle as expected in the normal state of the ice-making apparatus  100  but to a normal time range including the normal cycle time and the time tolerance. 
     In one embodiment, when among the actual total number of the ice forming and removing cycle, the number of the ice forming and removing cycles, each having the cycle time exceeding the normal time range, exceeds a predetermined value, the control unit may be configured to determine that the ice-making apparatus  100  is in an abnormal state. 
     In this connection, as described above, a predetermined time range may be embodied as a sum of the normal cycle time and the time tolerance. 
     In embodiments, in order to determine whether the ice-making apparatus  100  is in an abnormal state, the control unit  150  may employ each cycle time spent for each ice forming and removing cycle as performed by the ice-making apparatus  100 , thereby to result in more reliable or accurate diagnosis of the ice-making apparatus  100 . 
     In some embodiments of the present disclosure, the control unit may include a memory to store therein a program for processing and controlling operations by the control unit  150 . In addition, the memory may perform a temporary storage of input/output data. Such memory may be embodied as any of known storage media. 
     The various embodiments described herein may be implemented in a recording medium readable by a computer or other machine, using, for example, software, hardware, or a combination thereof. 
     According to a hardware implementation, the embodiments described herein may be implemented using at least one of ASICs (application specific integrated circuits), DSPs (digital signal processors), DSPDs (digital signal processing devices), PLDs (programmable logic devices), FPGAs (field programmable gate arrays), processors, controllers, microcontrollers, microprocessors, and electrical units for performing other functions. In some cases, the embodiments described herein may be implemented using the control module  120  itself. 
     According to a software implementation, embodiments such as the procedures and functions described herein may be implemented with separate software modules. Each of the software modules may perform one or more of the functions and operations described herein. The software module may be implemented with a software application written in a suitable programming language. The software module may be stored in the memory and executed by the control unit  150 . 
     The description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art upon reading the present disclosure. The generic principles defined herein may be applied to other embodiments without departing from the scope of the present disclosure. Thus, the present disclosure is not to be construed as limited to the embodiments set forth herein but is to be accorded the widest scope consistent with the principles and novel features presented herein.