Patent Publication Number: US-2023142165-A1

Title: Shelf device and storage cabinet

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Chinese Application No. 202010192553.7, filed on Mar. 18, 2020, entitled “Shelf Device and Storage Cabinet”, which is hereby incorporated by reference in its entity. 
     TECHNICAL FIELD 
     The present application relates to the technical field of storage apparatus, and in particular, to a shelf device and a storage cabinet. 
     BACKGROUND 
     At present, in order to adapt to items with different specifications, some high-end refrigerators are provided with lifting racks to adjust the height of shelves. However, in order to realize the independent adjustment of each shelf, the inner wall of the refrigerator needs to be provided with a set of lifting racks for each shelf, which not only increases the cost, but also creates a high installation difficulty in limited space of the refrigerator and affects the aesthetics. In addition, a set of driving devices is required to be provided for each set of lifting racks. Fixing the driving devices in the refrigerator will occupy the internal space of the refrigerator. 
     SUMMARY 
     An objective of the present application is to solve at least one of the problems existing in the related art. Therefore, the present application provides a shelf device, which has a simplified structure and can reduce the space occupied by a driving assembly. 
     The present application further provides a storage cabinet. 
     In a first aspect, the shelf device according to an embodiment of the present application includes: 
     a shelf body; 
     a support rack including a lead screw and a connecting bracket, the lead screw being fixedly connected with the connecting bracket; and 
     a driving assembly connected with the shelf body, the driving assembly including a driving component and a threaded sleeve, the driving component being dynamically coupled with the threaded sleeve, the threaded sleeve being threadedly connected with the lead screw. 
     According to the shelf device of an embodiment of the present application, only one set of lead screws is required to realize independent adjustment of a plurality of shelf bodies, which not only saves costs, but also facilitates mounting, and provides good-looking and concise appearance. Moreover, whether the shelf body is in a moving state or a fixed state, it is threadedly connected to the lead screw through the threaded sleeve. Therefore, the shelf body will not slide down because of load bearing or self-weight under the joint constraint of an external thread of the lead screw and an internal thread of the threaded sleeve, which meets the load-bearing demand of the shelf body. In addition, the mounting space of the driving assembly can be saved because the driving assembly is connected to the shelf body. 
     According to an embodiment of the present application, the shelf device further includes: 
     a mounting rack provided with a bearing assembly, and the threaded sleeve being pivotally mounted on the mounting rack through the bearing assembly. 
     According to an embodiment of the present application, the mounting rack includes a first mounting rack and a second mounting rack; 
     a side of the first mounting rack facing the second mounting rack is provided with a first mounting groove; 
     a side of the second mounting rack facing the first mounting rack is provided with a second mounting groove; and 
     the bearing assembly includes: 
     a first bearing provided in the first mounting groove; and 
     a second bearing provided in the second mounting groove. 
     According to an embodiment of the present application, a peripheral surface of a first end of the threaded sleeve is provided with a first shaft shoulder abutting against an end surface of an inner ring of the first bearing, and the first bearing is clamped with the first shaft shoulder and a groove bottom of the first mounting groove; and 
     a peripheral surface of a second end of the threaded sleeve is provided with a second shaft shoulder abutting against an end face of an inner ring of the second bearing, and the second bearing is clamped with the second shaft shoulder and a groove bottom of the second mounting groove clamp. 
     According to an embodiment of the present application, the groove bottom of the first mounting groove is provided with a first through hole, a first end of the threaded sleeve is provided to pass the first bearing and the first through hole, the groove bottom of the first mounting groove is provided with a first sinking groove passing through or corresponding to the first through hole, and the first sinking groove is used for oil storage; and 
     the groove bottom of the second mounting groove is provided with a second through hole, a second end of the threaded sleeve is provided to pass the second bearing and the second through hole, the groove bottom of the second mounting groove is provided with a second sinking groove passing through or corresponding to the second through hole, and the second sinking groove is used for oil storage. 
     According to an embodiment of the present application, the mounting rack further includes: 
     a third mounting rack provided between the first mounting rack and the second mounting rack; and 
     a step surface provided along an outer edge of the second mounting rack and matched to a shape of the third mounting rack. 
     According to an embodiment of the present application, an avoidance hole matched to the threaded sleeve is provided on the third mounting rack, and a boss abutting against an end surface of an outer ring of the second bearing is provided along a circumferential direction of the avoidance hole. 
     According to an embodiment of the present application, an inner hole of the threaded sleeve includes a thread segment and a smooth hole segment, and the diameter of the thread segment is smaller than or equal to the diameter of the smooth hole segment. 
     According to an embodiment of the present application, the shelf device further includes: 
     a gear set dynamically coupled with the driving component and the threaded sleeve respectively; and 
     an external gear engaged with the gear set and provided on the threaded sleeve. 
     According to an embodiment of the present application, the gear set has a transmission stage greater than or equal to two. 
     According to an embodiment of the present application, there is a plurality of the shelf bodies, and each shelf body is connected to the lead screw through a matched driving assembly. 
     In a second aspect, the storage cabinet according to an embodiment of the present application, includes a cabinet body and the above-mentioned shelf device, and the shelf device is provided in the cabinet body. 
     According to an embodiment of the present application, the storage cabinet is a refrigerator, a kitchen cabinet, or a display cabinet. 
     The above-mentioned one or more solutions in the embodiments of the present application have at least one of the following effects. 
     According to the shelf device provided by the embodiment of the present application in the first aspect, the lead screw is fixed because the lead screw is fixedly connected with the connecting bracket. A threaded sleeve is sleeved on the lead screw, and the threaded sleeve is connected with the shelf body. Therefore, it is only necessary to provide a set of lead screws, sleeve a plurality of threaded sleeves on it, and connect the plurality of threaded sleeves with different shelf bodies respectively. Independent adjustment of the plurality of shelf bodies can be realized without providing a plurality of sets of lead screws, which not only saves the cost, but also facilitates mounting, and provides good-looking and concise appearance. Moreover, whether the shelf body is in a moving state or a fixed state, it is threadedly connected to the lead screw through the threaded sleeve. Therefore, the shelf body will not slide down because of load bearing or self-weight under the joint constraint of an external thread of the lead screw and an internal thread of the threaded sleeve, which meets the load-bearing demand of the shelf body. In addition, the mounting space of the driving assembly can be saved because the driving assembly is connected to the shelf body. 
     According to the storage cabinet provided by the embodiment of the present application in the second aspect, by providing the above-mentioned shelf device inside the storage cabinet, the space occupied by the shelf device can be reduced, and the space utilization rate inside the storage cabinet can be improved. 
     In addition to the problems solved by the present application described above, the features of the constituted solutions, and the advantages brought by the features of these solutions, other features of the present application and the advantages brought by these features will be further described in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       To more clearly illustrate the embodiments of the present application or prior art, drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings may also be obtained according to these drawings without creative effort. 
         FIG.  1    is a schematic structural diagram of a shelf device provided by an embodiment of the present application; 
         FIG.  2    is a schematic structural diagram of mounting a driving assembly and a lead screw provided by an embodiment of the present application; 
         FIG.  3    is a schematic exploded view of mounting a driving assembly and a lead screw provided by an embodiment of the present application; 
         FIG.  4    is a schematic cross-sectional view of a driving assembly provided by an embodiment of the present application; 
         FIG.  5    is an enlarged view of part A in  FIG.  4   . 
     
    
    
     REFERENCE NUMERALS 
     
         
         
           
               100 : shelf body;  102 : lead screw;  104 : connecting bracket;  106 : driving component;  108 : threaded sleeve;  110 : first mounting rack;  112 : second mounting rack;  114 : first mounting groove;  116 : second mounting groove;  118 : first bearing;  120 : second bearing;  122 : first shaft shoulder;  124 : second shaft shoulder;  126 : first sinking groove;  128 : second sink groove;  130 : third mounting rack;  132 : step surface;  134 : avoidance hole;  136 : boss;  138 : threaded segment;  140 : smooth hole segment;  142 : gear set;  144 : external gear;  146 : mounting column;  148 : mounting hole;  150 : guide rod;  152 : connecting plate;  154 : sliding block. 
           
         
       
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The embodiments of the present application will be described in further detail below with reference to the drawings and embodiments. The following embodiments are intended to illustrate the present application, but not to limit the scope of the present application. 
     In the description of the present application, it is to be noted that, the orientation or positional relations specified by terms such as “central”, “longitudinal”, “transverse”, “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer” and the like, are based on the orientation or positional relations shown in the drawings, which is merely for convenience of description of the present application and to simplify description, but does not indicate or imply that the stated devices or components must have the particular orientation and be constructed and operated in a particular orientation, and thus it is not to be construed as limiting the present application. Furthermore, the terms “first”, “second”, “third” and the like are only used for descriptive purposes and should not be construed as indicating or implying a relative importance. 
     In the description of the present application, it is to be noted that unless explicitly specified and defined otherwise, the terms “connected to” and “connected” shall be understood broadly, for example, it may be either fixedly connected or detachably connected, or can be integrated; it may be either mechanically connected, or electrically connected; it may be either directly connected, or indirectly connected through an intermediate medium. The specific meanings of the terms above in the present application can be understood by a person skilled in the art in accordance with specific conditions. 
     In the embodiments of the present application, unless otherwise expressly specified and defined, a first feature is “on” or “under” a second feature can refer to that the first feature is directly contacted with the second feature, or the first feature is indirectly contacted with the second feature through an intermediate medium. And further, the first feature is “on”, “above” and “over” the second feature can refer to that the first feature is directly above or obliquely above the second feature, or simply refer to that the level height of the first feature is higher than that of the second feature. The first feature is “under”, “below” and “beneath” the second feature can refer to that the first feature is directly below or obliquely below the second feature, or simply refer to that the level height of the first feature is lower than that of the second feature. 
     In the description of this specification, description with reference to the terms “one embodiment”, “some embodiments”, “an example”, “specific example”, “some examples” and the like, refers to that specific features, structures, materials, or characteristics described in combination with an embodiment or an example are included in at least one embodiment or example according to the embodiments of the present application. In this specification, schematic representations of the above terms are not necessarily directed to a same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples, without conflicting each other. 
     As shown in  FIG.  1    to  FIG.  5   , an embodiment of the present application provides a shelf device, which includes: a shelf body  100 ; a support rack, including a lead screw  102  and a connection bracket  104 , and the lead screw  102  is fixedly connected with the connecting bracket  104 ; a driving assembly connected with the shelf body  100 , the driving assembly includes a driving component  106  and a threaded sleeve  108 , the driving component  106  is dynamically coupled with the threaded sleeve  108 , and the threaded sleeve  108  is threadedly connected with the lead screw  102 . 
     According to the shelf device of the embodiment of the present application, the lead screw  102  is fixed because the lead screw  102  is fixedly connected with the connecting bracket  104 . A threaded sleeve  108  is sleeved on the lead screw  102 , and the threaded sleeve  108  is connected with the shelf body  100 . Therefore, it is only necessary to provide a set of lead screws  102 , sleeve a plurality of threaded sleeves  108  on it, and connect the plurality of threaded sleeves  108  with different shelf bodies  100  respectively. Independent adjustment of the plurality of shelf bodies  100  can be realized without providing a plurality of sets of lead screws  102 , which not only saves the cost, but also facilitates mounting, and provides good-looking and concise appearance. Moreover, whether the shelf body  100  is in a moving state or a fixed state, it is threadedly connected to the lead screw  102  through the threaded sleeve  108 . Therefore, the shelf body  100  will not slide down because of load bearing or self-weight under the joint constraint of an external thread of the lead screw  102  and an internal thread of the threaded sleeve  108 , which meets the load-bearing demand of the shelf body  100 . In addition, the mounting space of the driving assembly can be saved because the driving assembly is connected to the shelf body  100 . Since the threaded sleeve  108  and the lead screw  102  are connected in threaded matching, when an item is placed on the shelf body  100 , the usage requirement for load-bearing can be met through the self-locking function of the threaded matching. 
     Specifically, the shelf device provided by an embodiment of the present application will be described below through applying the shelf device provided by an embodiment of the present application to a refrigerator. 
     The shelf body  100  is used to bearing items, such as items that need to be refrigerated. 
     The support rack includes a lead screw  102  and a connecting bracket  104 . The lead screw  102  is provided vertically, and two ends of the lead screw  102  are fixedly connected to the connecting bracket  104 . The connecting bracket  104  can be fixed on an inner wall of a box of the refrigerator. 
     The lead screw  102  can be a common lead screw or a rolling ball lead screw. 
     The driving assembly is detachably connected to the shelf body  100 , and the function of the driving assembly is to drive the shelf body  100  to move along the length direction of the lead screw  102 . The driving assembly includes a driving component  106  and a threaded sleeve  108 . The driving component  106  can be a motor, preferably a stepping motor. The stepping motor has advantages of high control accuracy, no accumulative error and the like. The threaded sleeve  108  is sleeved on the lead screw  102  and is threadedly connected with the lead screw  102 . Meanwhile, the threaded sleeve  108  is further dynamically coupled with the driving component  106 . In this way, when the driving component  106  is activated, it can be transmitted with the threaded sleeve  108 , and the threaded sleeve  108  can rotate along the axis of the lead screw  102 , thereby forming a displacement along the lead screw  102 . As mentioned above, since the driving assembly is mounted on the shelf body  100 , the movement of the threaded sleeve  108  can drive the shelf body  100  to move synchronously relative to the lead screw  102 , thereby realizing the lifting and lowering of the shelf body  100 . 
     It can be seen that, in an embodiment of the present application, by providing only one or a pair of lead screws  102 , providing a plurality of threaded sleeves  108  and a driving component  106  on the lead screw  102 , and providing a shelf body  100  corresponding to each threaded sleeve  108  and driving component  106 , independent adjustment of the plurality of shelf bodies  100  can be realized without providing a plurality of sets of lead screws  102 . Moreover, since the driving component  106  operates synchronously with the shelf body  100 , there is no need to additionally provide a space in the box of the refrigerator for accommodating the driving component  106 , thereby effectively saving the usage space inside the refrigerator. 
     As shown in  FIG.  2    to  FIG.  5   , the shelf device provided by the embodiment of the present application further includes a mounting rack. The mounting rack is provided with a bearing assembly, and the threaded sleeve  108  is pivotally mounted on the mounting rack through the bearing assembly. 
     The mounting rack is configured to mount the driving assembly. The bearing assembly is provided in the mounting rack, and the threaded sleeve  108  is sleeved on the bearing assembly, thereby realizing the smooth rotation of the threaded sleeve  108 , improving the rotation efficiency of the threaded sleeve  108 , and reducing the friction loss during the rotation of the sleeve  108 , and reducing the noise when the threaded sleeve  108  rotates and the threaded sleeve  108  engages with the leas screw  102  for transmission. 
     Specifically, the mounting rack in an embodiment of the present application includes a first mounting rack  110  and a second mounting rack  112 ; the bearing assembly includes a first bearing  118  and a second bearing  120 . 
     The first mounting rack  110  specifically refers to the upper mounting rack as shown in  FIG.  3   ; the second mounting rack  112  specifically refers to the lower mounting rack as shown in  FIG.  3   . A side of the first mounting rack  110  facing the second mounting rack  112  is provided with a first mounting groove  114 , and a side of the second mounting rack  112  facing the first mounting rack  110  is provided with a second mounting groove  116 ; the first bearing  118  is provided in the first mounting groove  114 , and the second bearing  120  is provided in the second mounting groove  116 . 
     Referring to  FIG.  3   , the first mounting rack  110  and the second mounting rack  112  are substantially rectangular open structures, and the first mounting rack  110  and the second mounting rack  112  are buckled with each other to roughly form a cuboid structure. 
     The shapes of the first mounting groove  114  and the second mounting groove  116  are matched to the shapes of the first bearing  118  and the second bearing  120  respectively. In an embodiment of the present application, the first mounting groove  114  may be formed by an upper surface of the first mounting rack  110  protruding upward, and an opening direction of the first mounting groove  114  is toward the second mounting rack  112 ; the second mounting groove  116  may be formed by a lower surface of the second mounting rack  112  protruding upward, and an opening direction of the second mounting groove  116  is toward the first mounting rack  110 . Moreover, an inner diameter of the first mounting groove  114  may be slightly smaller than or equal to an outer diameter of an outer ring of the first bearing  118 , so that the clamping of the first bearing  118  can be better achieved by interference fit. Similarly, an inner diameter of the second mounting groove  116  may be set to be slightly smaller than or equal to an outer diameter of an outer ring of the second bearing  120 . 
     In addition, by providing the first mounting groove  114  and the second mounting groove  116  on the first mounting rack  110  and the second mounting rack  112  respectively, axial positioning of the first bearing  118  and the second bearing  120  can be respectively achieved by a groove bottom of the first mounting groove  114  and a groove bottom of the second mounting groove  116 . That is, the groove bottom of the first mounting groove  114  prevents the first bearing  120  from moving upward, and the groove bottom of the second mounting groove  116  prevents the second bearing  120  from moving downward. 
     The objective of providing the bearing is to reduce the friction force during the threaded sleeve  108  rotates, thereby reducing the noise when the threaded sleeve  108  rotates. Therefore, two ends of the threaded sleeve  108  are provided to pass the inner ring of the first bearing  118  and an inner ring of the second bearing  120  respectively. In this way, when the threaded sleeve  108  rotates, the above-mentioned objective can be achieved through the action of the first bearing  118  and the second bearing  120 . 
     Referring to  FIG.  5   , a peripheral surface of a first end of the threaded sleeve  108  is provided with a first shaft shoulder  122  abutting against an end surface of an inner ring of the first bearing  118 , and the first bearing  118  is clamped with the first shaft shoulder  122  and a groove bottom of the first mounting groove  114 ; a peripheral surface of a second end of the threaded sleeve  108  is provided with a second shaft shoulder  124  abutting against an end face of an inner ring of the second bearing  120 , and the second bearing  120  is clamped with the second shaft shoulder  124  and a groove bottom of the second mounting groove  116 . 
     As mentioned above, the groove bottom of the first mounting groove  114  prevents the first bearing  118  from moving upward, and the groove bottom of the second mounting groove  116  prevents the second bearing  120  from moving downward. In order to further preventing the first bearing  118  and the second bearing  120  from moving in a mutually approaching direction, the first end and the second end of the threaded sleeve  108  are respectively provided with the first shaft shoulder  122  and the second shaft shoulder  124 . The first end of the threaded sleeve  108  specifically refers to an upper end of the threaded sleeve  108  shown in  FIG.  5   , and a lower end of the threaded sleeve  108  specifically refers to the lower end of the threaded sleeve  108  shown in  FIG.  5   . 
     Moreover, an outer diameter of the first shaft shoulder  122  is larger than the diameter of an inner ring of the first bearing  118 , an outer diameter of the second shaft shoulder  124  is larger than the diameter of an inner ring of the second bearing  120 , and the outer diameter of the first shaft shoulder  122  may be set to be equal with the outer diameter of the second shaft shoulder  124 . In this way, the first shaft shoulder  122  matches with the groove bottom of the first mounting groove  114  to realize axial limiting of the first bearing  118 ; the second shaft shoulder  124  matches with the groove bottom of the second mounting groove  116  to realize axial limiting of the second bearing  120 . When the threaded sleeve  108  rotates, the first bearing  118  and the second bearing  120  will not move axially, which ensures the rotation accuracy of the threaded sleeve  108 . 
     Referring to  FIG.  3    and  FIG.  5   , since the threaded sleeve  108  is sleeved on the lead screw  102 , the lead screw  102  also passes through the first mounting rack  110  and the second mounting rack  112  in sequence. In order to achieve the above objection, the first mounting groove  114  is provided with a first through hole, the groove bottom of the second mounting groove  116  is provided with a second through hole. A first end of the threaded sleeve is provided to pass the first bearing  118  and the first through hole, a second end of the threaded sleeve  108  is provided to pass the second bearing  120  and the second through hole. 
     Further, the diameter of the first through hole may be slightly smaller than the diameter of an outer ring of the first bearing  118 , and the diameter of the second through hole may be slightly smaller than the diameter of an outer ring of the second bearing  120 . In this way, the clamping of the first bearing  118  and the second bearing  120  can be better achieved. 
     Still further, the groove bottom of the first mounting groove  114  is provided with a first sinking groove  126  passing through or corresponding to the first through hole; the groove bottom of the second mounting groove  116  is provided with a second sinking groove  128  passing through or corresponding to the second through hole. The first sinking groove  126  and the second sinking groove  128  are used for oil storage. 
     As shown in  FIG.  5   , the first sinking groove  126  may be a sinking structure formed on an outer edge of the first through hole, and the second sinking groove  128  may be a sinking structure formed on an outer edge of the second through hole. By providing the first sinking groove  126  and the second sinking groove  128 , it can be ensured that a certain amount of lubricating oil is stored in the first sinking groove  126  and the second sinking groove  128 , which improves stability and flexibility during the rotation of the first bearing  118  and the second bearing  120 . 
     Referring to  FIG.  3   , the mounting rack further includes a third mounting rack  130  provided between the first mounting rack  110  and the second mounting rack  112 . 
     In order to ensure the successful installation of the third mounting rack  130  with the first mounting rack  110  and the second mounting rack  112 , the outer contour shape of the third mounting rack  130  can be set to be adaptable with the first mounting rack  110  and the second mounting rack  112 . As shown in  FIG.  3   , the third mounting rack  130  can be a platy structure. In addition, upper and lower surfaces of the third mounting rack  130  are further provided with a mounting column  146  matched with the first mounting rack  110  and the second mounting rack, and the mounting column  146  is provided with a threaded hole. Open holes can be opened on the first mounting rack  110  and the second mounting rack  112  at the positions corresponding to the mounting column  146 . Then the first mounting rack  110  and the second mounting rack  112  are respectively connectedly fixed to the third mounting rack  130  through fasteners such as screws. 
     Further, in order to ensure stable connection between the third mounting rack  130  and the second mounting rack  112 , a step surface  132  is provided along an outer edge of the second mounting rack  112  and is matched to a shape of the third mounting rack  130 . That is, the third mounting rack  130  can be set on the step surface  132 . 
     Further referring to  FIG.  3    and  FIG.  5   , the third mounting rack  130  is further provided with an avoidance hole  134  matched to the threaded sleeve  108 , and a boss  136  abutting against an end surface of the outer ring the second bearing  120  is provided along a circumferential direction of the avoidance hole  134 . 
     In this way, the boss  136  provided along the circumferential direction of the avoidance hole  134  matches with the second shaft shoulders  124  on the above-mentioned threaded sleeves  108 , which can further clamp the second bearing  120  in the second mounting groove  116 , and prevent the second bearing  120  from moving axially. 
     As shown in  FIG.  5   , an inner hole of the threaded sleeve  108  includes a thread segment  138  and a smooth hole segment  140 , and the diameter of the thread segment  138  is smaller than or equal to the diameter of the smooth hole segment  140 . 
     The objective of this arrangement is that when mounting the threaded sleeve  108 , the smooth hole segment  140  is first mounted on the lead screw  102 , and then the thread segment  138  is mounted on the lead screw  102 , which more easily realizes the assembly of the threaded sleeve  108  and the lead screw  102 . In addition, a certain amount of lubricating oil can further be stored in the smooth hole segment  140  to ensure the flexibility of the rotation of the threaded sleeve  108 . Moreover, this can also facilitate the processing of the threaded sleeve  108 , that is, it is only required to process a certain length of the thread segment  138  in the inner hole of the threaded sleeve  108 . In some other embodiments, only the threaded segment  138  may be provided. In addition, it should be noted that the length of the thread segment  138  should not be set too short, to avoid shaking of the threaded sleeve  108  when the thread segment  138  engages with the lead screw  102  for transmission. 
     Referring to  FIG.  3    and  FIG.  5   , the shelf device further includes a gear set  142  dynamically coupled with the driving component  106  and the threaded sleeve  108  respectively; an external gear  144  engaged with the gear set  142  and provided on the threaded sleeve  108 ; and the gear set  142  has a transmission stage greater than or equal to two. 
     In an embodiment of the present application, by using the gear set  142  as a transmission assembly, it is ensured that the transmission assembly has the advantages of accurate transmission, high efficiency, compact structure, reliable operation, and long service life. Therefore, in order to realize the dynamically coupled connection between the threaded sleeve  108  and the gear set  142 , external gear  144  is provided on an outer peripheral surface of the threaded sleeve  108 . The external gear  144  may be of a structure similar to a ring gear. 
     In addition, the gear set  142  is provided to have a transmission stage greater than or equal to two, which can improve the transmission precision during the transmission of the gear set  142 . 
     Moreover, it should be noted that the gear set  142  is also mounted inside the mounting rack. According to an embodiment of the present application, since the gear set  142  is used as a transmission component, the first mounting rack  110 , the second mounting rack  112  and the third mounting rack  130  are further provided with mounting holes  148  for mounting a gear shaft. 
     In an embodiment of the present application, the number of the shelf body  100  may be one or more. 
     As shown in  FIG.  1   , when there is a plurality of shelf bodies  100 , each shelf body  100  is connected to the lead screw  102  through a driving assembly matched with the shelf body  100 . In this way, only one lead screw  102  is required, and a plurality of shelf bodies  100  are connected to the lead screw  102  through the driving assembly, to realize independent adjustment of a plurality of shelf bodies  100 , which greatly simplifies the structure of the shelf device. In addition, since the driving assembly operates synchronously with the shelf body  100 , there is no need to provide a space in the box of the refrigerator for placing the driving assembly, which improves the space utilization rate of the refrigerator. 
     In addition, a guide rod  150  can further be provided on a side of the lead screw  102  to improve the stability of the shelf body  100  during movement. Two ends of the guide rod  150  can also be fixedly connected to an inner wall of the box of the refrigerator through the connecting bracket  104 . In addition, the driving assembly can be connected to the guide rod  150  through a connecting plate  152 , a sliding block  154  or other structures. 
     The storage cabinet according to an embodiment of the present application in the second aspect includes a cabinet body and the above-mentioned shelf device. The shelf device is provided in the cabinet body. 
     By providing the above-mentioned shelf device in its interior, the storage cabinet provided by an embodiment of the present application in the second aspect can reduce the space occupied by the shelf device and improve the space utilization rate inside the storage cabinet. More importantly, by providing the above-mentioned shelf device in the storage cabinet, a plurality of shelf bodies  100  can be mounted on a single lead screw  102 . Then only a single lead screw  102  is required, and adjustment of each shelf body  100  can be achieved independently through the matching of the driving assembly and the single lead screw  102 , which greatly simplifies the structure of the shelf device. 
     The storage cabinet in the embodiment of the present application may be, but not limited to, a refrigerator, a kitchen cabinet or a display cabinet. The structure and principle of the shelf device in this embodiment are the same as the structure and principle of the shelf device in the above-mentioned embodiment, and will not be repeated in this embodiment. 
     The above embodiments are only used to illustrate the present application, but not to limit the present application. Although the present application has been described in detail with reference to the embodiments, those of ordinary skill in the art should understand that various combinations, modifications, or equivalent replacements to the solutions of the present application will not depart from the spirit and scope of the solutions of the present application, and should cover within the scope of the claims of this application.