Patent Publication Number: US-2023148695-A1

Title: Clothes folding device

Description:
TECHNICAL FIELD 
     The present disclosure relates to an automated device that performs the folding of clothes. 
     BACKGROUND ART 
     Clothes are made of soft materials such as natural or synthetic fiber, etc., and folding of clothes must be performed to an appropriate size and shape for the purpose of storage and transport thereof. 
     Generally, clothes are required to be folded very frequently or in large amounts for storage after being washed or for long-term storage according to seasonal changes. However, direct folding of clothes by manpower causes waste of time and resources. Also, when the shape and size of folded clothes do not match due to unskilled manpower, additional labor must be input in for display or storage. 
     Accordingly, there is an increasing need for an automated device (hereinafter, referred to as a “clothes folding device”) which quickly and uniformly perform the folding of clothes. PCT Publication No. 2018-122841 issued on Jul. 5, 2018 discloses a conventional clothes folding device (title of the invention: DOMESTIC COMPACT ARTICLE FOLDING MACHINE HAVING STACKED CONVEYOR LAYERS AND FOLDING METHOD THEREFOR) (hereinafter, referred to as “prior art document”). The prior art document includes technical characteristics of an automated device which performs folding in the process that clothes are pushed in the upper portion and transported, and then discharges from the lower portion. 
     However, the device of the prior art has the following problems. 
     The folded clothes are dropped and loaded on a seating plate of a drawer provided at the lower portion of the device. In order for the clothes to be stably seated on the seating plate during the loading process, the seating plate performs up and down and forward and backward movements. More specifically, in order for the clothes to approach the drop point of the clothes, the seating plate performs an upward movement, and then performs a forward and backward movement such that one side of the clothes can be sequentially seated. In particular, in order for the entire area of one side of the clothes to be stably seated on the seating plate, the seating plate must be able to move sufficiently forward or backward. Accordingly, in order to implement this structure, the overall size of the device, particularly, the front-rear width must be sufficiently large, or otherwise, even though the size of the device is reduced, the drawer provided with the seating plate must be pulled out forward or backward in order to secure a space for the seating plate to protrude. 
     DISCLOSURE 
     Technical Problem 
     The purpose of the present disclosure is to solve a problem that, in the clothes folding device, in the process of unloading the folded clothes and loading, the size of the clothes folding device is unnecessarily increased in order to secure a forward and backward space when the unloading is performed, or a problem that the drawer must repeatedly protrude to the front or rear of the device. 
     Technical Solution 
     One embodiment is a clothes folding device which functions to perform folding in a process of transporting clothes. The clothes folding device includes: a loading assembly which pushes in the clothes and seats the clothes on a loading conveyor for transportation; a folding assembly which transports the clothes forward or backward and performs the folding of the clothes; an unloading assembly which is provided below the folding assembly and loads the clothes discharged from the folding assembly. The unloading assembly includes: an upper unloading layer where the clothes finally folded by the folding assembly is primarily dropped and seated and which comprises an unloading conveyor; a rotation drive unit which drives such that the unloading conveyor rotates; an upper front-rear drive unit which moves the upper unloading layer in a forward and backward direction; a lower unloading layer where the clothes seated on the upper unloading layer are secondarily dropped and seated; and an up and down drive unit which moves the lower unloading layer in an up or down direction. 
     The rotation drive unit and the upper front-rear drive unit rotate together while the secondary dropping is performed. The rotation drive unit and the upper front-rear drive unit are driven such that when a top surface of the unloading conveyor moves forward, the upper unloading layer moves backward, and when the top surface of the unloading conveyor moves backward, the upper unloading layer moves forward. 
     The up and down drive unit is driven such that, while the secondary dropping is performed, a secondary drop distance, that is, a distance from an uppermost end of the clothes loaded on the lower unloading layer or a top surface of the lower unloading layer on which the clothes are not loaded to the upper unloading layer maintains a first distance. 
     The up and down drive unit is driven such that, while the secondary dropping is performed, a secondary drop distance, that is, a distance from an uppermost end of the clothes loaded on the lower unloading layer or a top surface of the lower unloading layer on which the clothes are not loaded to the upper unloading layer increases from a second distance to a third distance. 
     The clothes folding device further includes a load sensor which senses a height of a top surface of the lower unloading layer or a height of an uppermost end of the clothes loaded on the lower unloading layer. 
     The clothes folding device further includes a frame which forms an external skeleton of the clothes folding device, is disposed at an outer edge, and defines a minimum working space of the clothes folding device. The unloading assembly further includes a drawer which forms a space in which clothes are loaded and mounts the lower unloading layer and the up and down drive unit. 
     The upper front-rear drive unit includes a rack-and-pinion structure installed on both sides of the upper unloading layer and in an area of the frame corresponding to both sides of the upper unloading layer. 
     The up and down drive unit includes the rack-and-pinion structure installed on both sides of the lower unloading layer and in a side of the drawer corresponding to both sides of the lower unloading layer. 
     The up and down drive unit includes a scissor type lift structure which is installed on a bottom surface of the drawer and has an upper portion to which the lower unloading layer is coupled. 
     The clothes folding device further includes a lower front-rear drive unit which moves the lower unloading layer forward or backward. The lower front-rear drive unit includes the rack-and-pinion structure which is fastened to the lower unloading layer and moves the lower unloading layer in the forward and backward direction. 
     The clothes folding device further includes a pressure guide provided on a lower surface of the upper unloading layer. The up and down drive unit is driven such that an uppermost end of the clothes loaded on the lower unloading layer is pressed by the pressure guide. 
     The unloading assembly further includes a drawer which forms a space in which clothes are stored. The up and down drive unit is driven such that when the drawer is opened to take out the clothes, a top surface of the lower unloading layer on which the clothes are not present or an uppermost end of the clothes loaded on the lower unloading layer maintains a predetermined distance from a bottom surface of the drawer. 
     A front-rear width of the upper unloading layer with respect to a space that the upper unloading layer occupies in the forward and backward direction is in a range of 0.28 to 0.36. A front-rear stroke distance of the upper unloading layer with respect to the space that the upper unloading layer occupies in the forward and backward direction is in a range of 0.5 to 0.65. 
     Another embodiment is a clothes folding device which functions to perform folding in a process of transporting clothes. The clothes folding device includes: a loading assembly which pushes in the clothes and seats the clothes on a loading conveyor for transportation; a folding assembly which transports the clothes forward or backward and performs the folding of the clothes; an unloading assembly which is provided below the folding assembly and loads the clothes discharged from the folding assembly. The unloading assembly includes: an upper unloading layer where the clothes finally folded by the folding assembly is primarily dropped and seated and which comprises an unloading conveyor; a rotation drive unit which drives such that the unloading conveyor rotates; a lower unloading layer where the clothes seated on the upper unloading layer are secondarily dropped and seated; a lower front-rear drive unit which moves the lower unloading layer forward and backward; and an up and down drive unit which moves the lower unloading layer in an up or down direction. 
     The lower front-rear drive unit is implemented as a rack-and-pinion structure. The up and down drive unit is implemented as a scissor type lift structure. The up and down drive unit is provided on the lower front-rear drive unit. 
     Advantageous Effects 
     According to at least one of the embodiments of the present disclosure, it is possible to minimize the front-rear width of the clothes folding device. 
     Also, according to at least one of the embodiments of the present disclosure, it is possible to increase the operational reliability of an unloading assembly driver. 
     Also, according to at least one of the embodiments of the present disclosure, it is possible to reduce the power consumption of the unloading assembly driver. 
     Further scope of applicability of the present invention will become apparent from the following detailed description for embodying the present invention. However, since various changes and modifications within the spirit and scope of the present invention can be clearly understood by those skilled in the art, specific embodiments such as embodiments included in the following detailed description for embodying the present invention should be understood as being merely illustrative. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG.  1    is a perspective view of a clothes folding device  10  according to an embodiment of the present disclosure; 
         FIG.  2    is a side view of the clothes folding device  10  of  FIG.  1   ; 
         FIG.  3    is a side view of the clothes folding device  10 , which shows a configuration of a folding assembly  200  according to the embodiment of the present disclosure; 
         FIG.  4    is a conceptual view showing a position where folding is performed in the folding assembly; 
         FIG.  5    is a flow chart showing an embodiment of the clothes folding method for the top of the clothes; 
         FIG.  6    is a flow chart showing an embodiment of the clothes folding method for the bottom of the clothes; 
         FIG.  7    is a flowchart showing an embodiment of the clothes folding method of towels; 
         FIGS.  8  and  9    show a first embodiment of an unloading assembly related to the present disclosure; 
         FIGS.  10  and  11    show a second embodiment of the unloading assembly related to the present disclosure; 
         FIGS.  12  and  13    show a third embodiment of the unloading assembly related to the present disclosure; 
         FIGS.  14  and  15    show a fourth embodiment of the unloading assembly related to the present disclosure; 
         FIGS.  16 A to  16 C  show an embodiment of a process in which clothes are secondarily dropped and seated from the upper unloading layer to the lower unloading layer in accordance with a time sequence; 
         FIGS.  17 A to  17 C  show an embodiment of a process in which clothes are secondarily dropped and seated from the upper unloading layer to the lower unloading layer in accordance with a time sequence; 
         FIG.  18    is a perspective view of the unloading assembly related to the present disclosure; and 
         FIGS.  19 A and  19 B  are side views of the unloading assembly related to the present disclosure. 
     
    
    
     MODE FOR INVENTION 
     Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings. The same or similar elements will be denoted by the same reference numerals irrespective of drawing numbers, and repetitive descriptions thereof will be omitted. A suffix “assembly” and “part” for the component, which is used in the following description, is given or mixed in consideration of only convenience for ease of specification, and does not have any distinguishing meaning or function per se. Also, in the following description of the embodiment disclosed in the present specification, the detailed description of known technologies incorporated herein is omitted to avoid making the subject matter of the embodiment disclosed in the present specification unclear. Also, the accompanied drawings are provided only for more easily describing the embodiment disclosed in the present specification. The technical spirit disclosed in the present specification is not limited by the accompanying drawings. All modification, equivalents and substitutes included in the spirit and scope of the present invention are understood to be included in the accompanying drawings. 
     While terms including ordinal numbers such as the first and the second, etc., can be used to describe various components, the components are not limited by the terms mentioned above. The terms are used only for distinguishing between one component and other components. 
     In the case where a component is referred to as being “connected” or “accessed” to another component, it should be understood that not only the component is directly connected or accessed to the other component, but also there may exist another component between them. Meanwhile, in the case where a component is referred to as being “directly connected” or “directly accessed” to another component, it should be understood that there is no component therebetween. 
     An expression of a singular form includes the expression of plural form thereof unless otherwise explicitly mentioned in the context. 
     In the present specification, it should be understood that the term “include” or “comprise” and the like is intended to specify characteristics, numbers, steps, operations, components, parts or any combination thereof which are mentioned in the specification, and intended not to previously exclude the possibility of existence or addition of at least one another characteristics, numbers, steps, operations, components, parts or any combination thereof. 
     Hereinafter, a clothes folding device  10  according to an embodiment of the present disclosure will be described based on the description of  FIGS.  1  to  3   .  FIG.  1    is a perspective view of the clothes folding device  10  according to an embodiment of the present disclosure.  FIG.  2    is a side view of the clothes folding device  10  of  FIG.  1   .  FIG.  3    is a side view of the clothes folding device  10 , which shows a configuration of a folding assembly  200  according to the embodiment of the present disclosure. 
     Referring to  FIGS.  1  to  2   , the clothes folding device  10  according to the embodiment of the present disclosure may be supported and installed in a frame  110 . The frame  110  may function as an external skeleton of the clothes folding device  10 . The frame  110  is disposed at the outer edge of the clothes folding device  10  and defines a minimum working space of the clothes folding device  10 , and can stably attach and support various members constituting the clothes folding device  10 . 
     The frame  110  includes an upper frame  111 , a lower frame  112 , and horizontal frames  113 ,  114 ,  115 ,  116 , and  117 . The frame  110  includes vertical frames  121 ,  122 ,  123 , and  124  disposed vertically to support the upper frame  111 , the lower frame  112 , and the horizontal frame. 
     A finish cover (not shown) may be stably attached to the outer surface of the frame  110 . The finish cover may form an exterior of the clothes folding device  10 . 
     The clothes folding device  10  includes a loading assembly  100 , a folding assembly  200 , and an unloading assembly  300 . 
     The loading assembly  100 , the folding assembly  200 , and the unloading assembly  300  may be supported by the frame  110 . In addition, working spaces of the loading assembly  100 , the folding assembly  200 , and the unloading assembly  300  may be defined by the frame  110 . 
     For example, the working space of the loading assembly  100  may be defined by the upper frame  111  and the horizontal frame  114 , and the working space of the unloading assembly  300  may be defined by the horizontal frame  116  and the lower frame  112 . 
     The loading assembly  100  is provided such that clothes are pushed in. The loading assembly  100  may be provided such that the pushed-in clothes can be placed on the upper surface of a conveyor  20 . Specifically, the loading assembly  100  may be placed on the upper surface of the conveyor  20  of a first folding layer  210  between the upper frame  111  and the horizontal frame  114 . 
     Here, the term “clothes” refers to a top or bottom made of natural or synthetic fibers that can be worn by humans, and also includes any article that can be provided folded to a desired size and thickness through the clothes folding device, such as a towel or blanket. 
     A plurality of conveyors  20  may be supported by horizontal frames  113 ,  114 ,  115 ,  116 , and  117 . 
     The folding assembly  200  is provided such that the pushed-in clothes are folded while being transported. The folding assembly  200  includes at least two folding layers such that the pushed-in clothes are folded to a certain size and shape while being transported. The at least two folding layers are placed above and below and are spaced apart from each other. As the pushed-in clothes are transported from the upper folding layer to the lower folding layer, folding occurs at least once in each folding layer, and as a result, the clothes which have been folded to a certain size and shape are loaded by the unloading assembly  300 . 
     More specifically, the folding assembly  200  may include four folding layers  210 ,  220 ,  230 , and  240 . The four folding layers  210 ,  220 ,  230 , and  240  may be placed above and below and are spaced apart from each other. As the pushed-in clothes are transported from the first upper folding layer  210  to the fourth lower folding layer  240 , the four folding layers function to cause the pushed-in clothes to be folded to a certain size and shape. The folding occurs at least once in each folding layer. In particular, the folding may occur twice in the fourth folding layer  240 . 
     The folding layers  210 ,  220 ,  230 , and  240  are responsible for seating, transporting, and folding clothes. Each of the folding layers  210 ,  220 ,  230 , and  240  is provided with at least one conveyor  20  to perform the functions described above, in particular transporting and folding. In particular, the clothes are folded by being inserted into two adjacent conveyors  20  on one folding layer. This is implemented such that the clothes can be folded or can pass while being folded, by a folding gap  201  between two adjacent conveyors  20  on one folding layer. 
     The four folding layers  210 ,  220 ,  230 , and  240  may include at least one conveyor  20 . The third folding layer  230  may include two conveyors  20 , and the fourth folding layer  240  may include three conveyors  20 . The folding gap  201  may be formed between the two conveyors provided in the third folding layer  230  in order to allow the clothes to pass through while being folded. Two folding gaps  201  may be formed between the three conveyors provided in the fourth folding layer  240  in order to allow the clothes to be folded or to pass through while being folded. 
     The clothes completely pass through the folding gap  201  and then may be folded and discharged to a lower layer at the same time, or may be inserted into the folding gap  201  and then pulled out again to maintain the layer and only folding may be performed. When only folding is performed in the folding gap  201 , the clothes are discharged to the lower layer through another folding gap  201  or through one end of a layer other than the folding gap  201  (for example, the rear end of the third folding layer  230 ). 
     As in the embodiment of  FIG.  3   , the clothes are vertically folded in upper two folding layers  210  and  220  of the four folding layers constituting the folding assembly  200  (strictly, the first vertical folding is performed in the loading assembly  100  of the layer where the folding layer  210  is positioned), and the clothes may be horizontally folded in the lower two folding layers  230  and  240 . 
     Here, the horizontal folding means that the clothes are folded with respect to a reference line perpendicular to a proceeding direction of the clothes. The direction perpendicular to the proceeding direction of the clothes is not limited to an exact angle of 90 degrees between the proceeding direction of the clothes and a folding line of the clothes, and includes an error range of 0 to 30 degrees. 
     Here, the vertical folding means that the clothes are folded with respect to a reference line parallel to the proceeding direction of the clothes. The direction parallel to the proceeding direction of the clothes is not limited to an exact angle of 0 degree between the proceeding direction of the clothes and a folding line of the clothes, and includes an error range of 0 to 30 degrees. 
       FIGS.  4  to  7    show various clothes folding methods by the clothes folding device according to the embodiment of the present disclosure.  FIG.  4    is a conceptual view showing a position where folding is performed in the folding assembly.  FIG.  5    is a flowchart showing an embodiment of the clothes folding method for the top of the clothes.  FIG.  6    is a flowchart showing an embodiment of the clothes folding method for the bottom of the clothes.  FIG.  7    is a flowchart showing an embodiment of the clothes folding method of towels. 
     The embodiment of the folding assembly  200  includes a first vertical folding step Si in which the clothes pushed into the clothes folding device according to the embodiment of the present disclosure are folded in the first folding layer  210 , a second vertical folding step S 2  in which the clothes are folded in the second folding layer  220 , a first horizontal folding step S 3  and S 4  in which the clothes are folded in the third folding layer  230 , and a second horizontal folding step S 5  and S 6  in which the clothes are folded in the fourth folding layer  240 . 
     The first horizontal folding step S 3  and S 4  includes a transport step S 3  in which the clothes are not folded and is transported to the lower fourth folding layer  240 , and a folding step S 4 . 
     The second horizontal folding step S 5  and S 6  includes a ⅓ folding step S 5  in which folding is performed at ⅓ point on the basis of the transport direction, and a ½ folding step S 6  in which folding is performed at ½ point on the basis of the transport direction. 
     According to the embodiment of  FIG.  5   , the top of the clothes pushed into the clothes folding device according to the embodiment of the present disclosure may be vertically folded in the first vertical folding step Si and the second vertical folding step S 2 , respectively. Then, the horizontal folding step is performed on the top. Two embodiments will be described. 
     According to a first embodiment, the clothes on which the vertical folding has been performed is transported (S 3 ) immediately without being folded in a third horizontal folding step. Then, the ⅓ folding step S 5  and the ½ folding step S 6  are sequentially performed in a fourth horizontal folding step, so that three-stage horizontally folded top can be discharged (the flowchart on the left in  FIG.  5   ). 
     According to a second embodiment, the clothes on which the vertical folding has been performed is transported (S 3 ) immediately without being folded in the third horizontal folding step. Then, only the ½ folding step S 6  is performed in the fourth horizontal folding step, so that four-stage horizontally folded top can be discharged (the flowchart on the right in  FIG.  5   ). 
     According to the embodiment of  FIG.  6   , the bottom of the clothes pushed into the clothes folding device according to the embodiment of the present disclosure may be vertically folded one time while going through the first vertical folding step Si and the second vertical folding step S 2 . That is, in the second vertical folding step S 2 , the folding by a vertical folding assembly is not performed and the clothes are immediately transported. Then, the horizontal folding step is performed on the bottom. Two embodiments will be described. 
     According to the first embodiment, the clothes on which the vertical folding has been performed is horizontally folded (S 4 ) in the third horizontal folding step. Then, the horizontal folding of the ½ folding step S 6  is subsequently performed in the fourth horizontal folding step, so that four-stage horizontally folded bottom can be discharged (the flowchart on the left in  FIG.  6   ). According to the second embodiment, the clothes on which the vertical folding has been performed is transported (S 3 ) immediately without being folded in the third horizontal folding step. Then, the ⅓ folding step S 5  and the ½ folding step S 6  are sequentially performed in the fourth horizontal folding step, so that three-stage horizontally folded bottom can be discharged (the flowchart on the right in  FIG.  6   ). 
     According to the embodiment of  FIG.  7   , the vertical folding step and the horizontal folding step are performed on towels pushed in by the clothes folding device according to the embodiment of the present disclosure. Three embodiments will be described. 
     According to the first embodiment, pushed-in towels may be vertically folded one time while going through the first vertical folding step Si and the second vertical folding step S 2 . That is, in the second vertical folding step S 2 , the folding by the vertical folding assembly is not performed and the towels are immediately transported. Subsequently, the horizontal folding is performed in the third horizontal folding step (S 4 ), and then the ⅓ folding step S 5  and the ½ folding step S 6  are sequentially performed in the fourth horizontal folding step, so that the towels having a size and shape of a hand towel suitable for being stored in a bathroom cabinet can be discharged (the flowchart on the left in  FIG.  7   ). 
     According to the second embodiment, the pushed-in towels may be vertically folded one time while going through the first vertical folding step Si and the second vertical folding step S 2 . That is, in the second vertical folding step S 2 , the folding by the vertical folding assembly is not performed and the towels are immediately transported. Subsequently, the horizontal folding is performed in the third horizontal folding step (S 4 ), and then the ½ folding step S 6  of the fourth horizontal folding step is immediately performed, so that the towels having a size and shape of a hand towel which are different from the size and shape of the hand towel of the first embodiment can be discharged (the flowchart in the middle of  FIG.  7   ). 
     According to a third embodiment, the pushed-in towels are immediately transported without being vertically folded while going through the first vertical folding step Si and the second vertical folding step S 2 . Then, the horizontal folding is performed in the third horizontal folding step (S 4 ), and then the ½ folding step S 6  of the fourth horizontal folding step is immediately performed, so that the towels having a size and shape of a hand towel which are different from the sizes and shapes of the hand towels of the first and second embodiments can be discharged (the flowchart on the right in  FIG.  7   ). According to another embodiment, a vertical folding layer may be added below the fourth folding layer  240  such that the horizontal folding is completed and then the vertical folding is additionally performed. In this case, the towels in the form of a hand towel having a vertical width smaller than that of the towel of the third embodiment can be discharged and be appropriately received in an intended bathroom cabinet. 
       FIGS.  8  to  15    show several embodiments of the unloading assembly  300  in accordance with the present disclosure.  FIGS.  8  and  9    show the first embodiment.  FIGS.  10  and  11    show the second embodiment.  FIGS.  12  and  13    show the third embodiment.  FIGS.  14  and  15    show a fourth embodiment. 
     The unloading assembly  300  of the present disclosure proposes a configuration in which two members are independently driven, unlike a conventional configuration in which one member moves and loads folded clothes. 
     The unloading assembly  300  according to the embodiment of the present disclosure includes an unloading layer  310  that performs at least a portion of seating, transporting, and folding clothes. Particularly, the unloading layer  310  includes an upper member which seats primarily the clothes that are dropped after being folded and a lower member which seats the clothes that are dropped secondarily from the upper member. The upper member is defined as an upper unloading layer  311 , and the lower member is defined as a lower unloading layer  312 . 
     Common features of the embodiments to be described below are as follows. The upper unloading layer  311  includes a conveyor, and thus, is able to transport clothes in one direction, and the lower unloading layer  312  is able to adjust the height in accordance with situations by moving up and down. Also, at least one of the upper unloading layer  311  and the lower unloading layer  312  is provided to be movable in a forward and backward direction. 
     The feature that the upper unloading layer  311  is able to transport clothes through the conveyor and the feature that at least one unloading layer is provided to be movable in a forward and backward direction can maximize a forward and backward space utilization in the unloading assembly  300 . 
     In particular, when the upper unloading layer  311  is provided to be movable in the forward and backward direction, the rotation and forward and backward movement of an unloading conveyor  20 B of the upper unloading layer  311  allows a position to which the clothes that are being dropped from the folding assembly  200  to be freely determined. To the extreme degree, even when the clothes have no choice but to be seated to be biased forward or backward as the clothes are dropped from the folding assembly  200  to a specific position and in a specific direction, the clothes can be seated in any desired position through the above movement of the upper unloading layer  311 . For example, when the clothes are discharged through steps S 5  or S 6  (see  FIGS.  4  to  7   ), as long as the bottom of the discharged clothes reaches the top surface of the upper unloading layer  311 , the unloading conveyor  20 B rotates counterclockwise while the clothes are dropped. Accordingly, the folded clothes can be seated on the upper unloading layer  311  without being wrinkled. 
     With respect to the forward and backward direction of the clothes folding device  10 , when the seating of the clothes is finished, the position of the upper unloading layer  311  is changed depending on cases. However, after the seating of the clothes is finished, the upper unloading layer  311  can move to the front end or rear end in accordance with the forward and backward movement of the upper unloading layer  311 . Accordingly, the upper unloading layer  311  which has moved to the front end or the rear end may variably determine a position at which the clothes are to be secondarily dropped to the lower unloading layer  312 . 
     As described above, by the moving mechanism of the upper unloading layer  311 , since the position of the clothes which are dropped to the upper unloading layer  311  and the position of the clothes which are dropped from the upper unloading layer  311  to the lower unloading layer  312  may be variably determined, the amount of the forward and backward space required of the clothes folding device  10  due to the corresponding area can be minimized. 
     Meanwhile, the up and down movement of the lower unloading layer  312  determines an up and down distance between the upper unloading layer  311  and the lower unloading layer  312  (strictly, an up and down distance between the uppermost surface of the upper unloading layer  311  and the uppermost surface of the lower unloading layer  312  on which the clothes are loaded, hereinafter, defined as “secondary drop distance”), thereby the clothes can be dropped by as much as an appropriate height. 
     For example, a top surface  3121  of the lower unloading layer on which the clothes are not loaded or an uppermost end  1 ′ of the loaded clothes (hereinafter, referred to as “the uppermost end of the loading portion”) can be located very close to the upper unloading layer  311 . When the uppermost end of the loading portion is provided adjacent to the upper unloading layer  311 , the clothes can be seated on the lower unloading layer  312  as stable as possible without floating in the air when being dropped, even though the folded clothes have a short front-rear width. 
     Alternatively, the clothes may be dropped secondarily in a state where the uppermost end of the loading portion and the upper unloading layer  311  are spaced apart from each other by a specific distance. Since a certain forward and backward length of the clothes is obtained by that the uppermost end of the loading portion and the upper unloading layer  311  are spaced apart from each other by a distance, even when the folded clothes have a forward and backward length, a space in which the clothes can be positioned without being wrinkled is obtained as much as possible. Therefore, even when the clothes of the upper unloading layer  311  are not stably dropped to the lower unloading layer  312  because the upper unloading layer  311  has a long front-rear length or the clothes folding device  10  has a narrow front-rear space, it is possible to produce the same effect as the increase of the front-rear width by reducing the height of the loading layer  312 . 
     The lower unloading layer  312  may be implemented to move in the forward and backward direction. This means that the forward and backward movement of the lower unloading layer  312  is practically beneficial when the front-rear width of the lower unloading layer  312  is smaller than the front-rear width of the clothes folding device  10 , and allows the drop point of the clothes to be variably determined when the clothes are dropped from the upper unloading layer  311  to the lower unloading layer  312 . 
     A rotation drive unit  410  and a translation drive unit  420  provide power for implementing a driving mechanism of the unloading assembly  300 . Each of the rotation drive unit  410  and the translation drive unit  420  may include at least one motor  30 . 
     The rotation drive unit  410  provides power for the rotational motion of the unloading conveyor  20 B provided in the upper unloading layer  311 . 
     The translation drive unit  420  provides power for the translation motion of the upper unloading layer  311  or the lower unloading layer  312 . In particular, an upper front-rear drive unit  421  provides power for the forward and backward movement of the upper unloading layer  311 , and an up and down drive unit  423  provides power for the up and down movement of the lower unloading layer  312 . A lower front-rear drive unit  422  provides power for the forward and backward movement of the lower unloading layer  312 . 
     The upper front-rear drive unit  421  and the lower front-rear drive unit  422  may include a rack-and-pinion structure  420 B. Meanwhile, the up and down drive unit  423  may alternatively include one of a scissor type lift structure  420 A and the rack-and-pinion structure  420 B. 
     It is essential to provide the rotation drive unit  410  that rotates the unloading conveyor  20 B and the up and down drive unit  423  that moves the lower unloading layer  312  in the up and down direction. Here, at least one of the upper front-rear drive unit  421  and the lower front-rear drive unit  422  may be provided. That is, only the lower front-rear drive unit  422  may be provided as in the first embodiment, or only the upper front-rear drive unit  421  may be provided as in the second and third embodiments. In addition, it goes without saying that both the upper front-rear drive unit  421  and the lower front-rear drive unit  422  may be provided as in the fourth embodiment. 
     In the case of the first embodiment ( FIGS.  8  and  9   ), the lower unloading layer  312  moves in the up and down direction by the up and down drive unit  423  and moves in the forward and backward direction by the lower front-rear drive unit  422 . Meanwhile, the upper unloading layer  311  is fixed to the frame  110  and performs only the rotation of the unloading conveyor  20 B. 
     The up and down drive unit  423  is implemented as the scissor type lift structure  420 A and moves the lower unloading layer  312  in the up and down direction, and the lower front-rear drive unit  422  is implemented as the rack-and-pinion structure  420 B and moves the lower unloading layer  312  in the forward and backward direction. In particular, the scissor type lift structure  420 A is formed within the rack-and-pinion structure  420 B, so that not only the lower unloading layer  312  but also the scissor type lift structure  420 A moves together in the forward and backward direction. 
     Even though the upper unloading layer  311  is fixed and the lower unloading layer  312  moves in the forward and backward direction, it is not difficult to determine the drop point of the clothes when the clothes are dropped secondarily. However, since the upper unloading layer  311  cannot move in the forward and backward direction even though the drop point of the clothes which are primarily dropped from the folding assembly  200  is determined, undesirable conditions are likely to occur. 
     Also, when the up and down drive unit  423  and the lower front-rear drive unit  422  are simultaneously implemented as in the first embodiment, the up and down drive unit  423  must be implemented on the structure of the lower front-rear drive unit  422 . For this reason, structural instability is caused and a space for transmitting the power is difficult to obtain. 
     To compensate this problem, the second embodiment ( FIGS.  10  and  11   ) proposes a structure in which the upper unloading layer  311  moves forward and backward by the upper front-rear drive unit  421 . 
     The rack-and-pinion structure  420 B constituting the upper front-rear drive unit  421  may be installed on both sides of the upper unloading layer  311  and in an area of the frame  110  corresponding to both sides of the upper unloading layer  311 . Thus, the upper unloading layer  311  can perform a relative movement with respect to the frame  110 . 
     When the clothes are dropped primarily from the folding assembly  200  to the upper unloading layer  311 , the upper front-rear drive unit  421  positions the upper unloading layer  311  such that the upper unloading layer  311  meets a vertical line of the drop point of the clothes (see  FIG.  4   ). Then, while the clothes are dropped to and seated on the upper unloading layer  311 , the rotation drive unit  410  rotates the unloading conveyor  20 B, thereby allowing the clothes to be seated on the upper unloading layer  311  without being wrinkled. 
     When the clothes are dropped secondarily from the upper unloading layer  311  to the lower unloading layer  312 , the rotation drive unit  410  and the upper front-rear drive unit  421  operate simultaneously to rotate the unloading conveyor  20 B and to move the lower unloading layer  312  in the forward and backward direction simultaneously. 
     The rotation of the unloading conveyor  20 B by the operation of the rotation drive unit  410  allows the clothes to be dropped from the upper unloading layer  311  without friction, and the movement of the upper unloading layer  311  by the operation of the upper front-rear drive unit  421  allows the clothes to be seated on the lower unloading layer  312  without being wrinkled. 
     Describing the operation in more detail, when the top surface  20 ′ of the unloading conveyor  20 B moves forward, the upper unloading layer  311  may move backward, and when the top surface  20 ′ of the unloading conveyor  20 B moves backward, the upper unloading layer  311  may move forward. 
     The up and down drive unit  423  may be implemented by the scissor type lift structure  420 A. The scissor type lift structure  420 A includes two link bars  4201  of which one side is rotationally fixed and the other side is slidingly fixed. The two link bars  4201  are provided to intersect each other, and the intersections of the two link bars  4201  are rotatably fastened to form an intersecting axis  4202 . A slide fixing point  4203  of one link bar  4201  and a rotation fixing point  4204  of the other link bar are fastened to the lower unloading layer  312 . the two link bars  4201  rotate relatively in accordance with the movement of the slide fixing point  4203 , so that the lower unloading layer  312  is lifted or lowered. 
     The up and down drive unit  423  implemented by the scissor type lift structure  420 A has a simple structure and occupies a relatively small space. However, the slide fixing point  4203  cannot be completely fixed to the frame  110  or the lower unloading layer  312 , so that the up and down drive unit  423  is structurally unstable. In particular, this causes a problem that the center of gravity closer to one side is formed when the lower unloading layer  312  is raised. In addition, a lot of initial torque is required to raise the lower unloading layer  312  from the lowermost end, so that it is disadvantageous in terms of energy efficiency. 
     In order to compensate this problem, the third embodiment ( FIGS.  12  and  13   ) proposes that the up and down drive unit  423  has the rack-and-pinion structure  420 B. The rack-and-pinion structure  420 B of the up and down drive unit  423  may be installed on both sides of the lower unloading layer  312  and on a side of a drawer  502  corresponding to both sides of the lower unloading layer  312 . 
     Here, said both sides may mean front and rear both sides or left and right both sides. Considering that a reinforcing rib  503  for improving the structural stability of the device should be provided on the left and right sides of the clothes folding device  10 , the rack-and-pinion structure  420 B is preferably provided on the front and rear both sides. 
     Here, the drawer  502  refers to a member that forms a space in which clothes are to be loaded in the unloading assembly  300 . The lower unloading layer  312  and the up and down drive unit  423  are mounted in the space formed by the drawer  502 , and the loaded clothes can be stored in the space. If necessary, the drawer  502  may be pulled out from the frame  110  by a predetermined distance, so that a user can easily take out the loaded clothes. 
     Here, the loading refers to clothes that are fully seated on the lower unloading layer  312  and can be taken out by the user, or a stacked state of such clothes. 
     A pinion gear  4206  is rotatably fixed to the lower unloading layer  312 , and a rack gear  4205  which forms a guide where the pinion gear is engaged and moves is provided on both sides of the drawer  502 . It is preferable that the rack gear  4205  and the pinion gear  4206  are coupled to the drawer  502  through a bracket  504  so that they are not exposed to the exterior of the drawer  502 . 
     In the case of this embodiment in which both the upper front-rear drive unit  421  and the lower front-rear drive unit  422  are provided in the form of the rack-and-pinion structure  420 B, structural stability of the two unloading layers  310  is ensured. That is, unlike the scissor type lift structure  420 A, two points supporting the lower unloading layer  312  are not only distributed on both sides but also support in a vertical direction, so that stress, particularly shear stress can be minimized to the minimum degree. Also, there is an advantage that the power by the drive unit can be transmitted without loss. 
     Also, since the upper unloading layer  311  can move forward and backward, the upper unloading layer  311  can be designed in such a way that a front-rear width W 1  thereof is formed to the minimum degree for the seating of the clothes. The fact that the front-rear width W 1  of the upper unloading layer  311  can be set to the minimum degree means that an area in which the upper unloading layer  311  covers the lower unloading layer  312  becomes smaller, so that a useless space can be minimized. For a concrete example, if a design condition of a width W 2  that the upper unloading layer  311  can occupy in the forward and backward direction on the clothes folding device  10  is in a range of about 600 mm to 650 mm, the front-rear width W 1  of the upper front-rear drive unit  421  that moves in the forward and backward direction can be designed in a range of 200 mm to 250 mm. Here, a front-rear stroke distance W 3  of the upper front-rear drive unit  421  at this point of time is about 400 mm. From the viewpoint of ratio, the front-rear width W 1  of the upper unloading layer  311  with respect to the space W 2  that the upper unloading layer  311  can occupy in the forward and backward direction is in a range of 0.28 to 0.36. Also, the front-rear stroke distance W 3  of the upper unloading layer  311  with respect to the space W 2  that the upper unloading layer  311  can occupy in the forward and backward direction is in a range of 0.5 to 0.65. 
     Meanwhile, as in the fourth embodiment ( FIGS.  14  and  15   ), the upper front-rear drive unit  421  and the lower front-rear drive unit  422  can be simultaneously implemented. Specific characteristics of each of the drive units are the same as those described in the first and second embodiments. Accordingly, the structure and characteristics described in each embodiment may be applied in the same manner. 
       FIGS.  16 A to  16 C  and  FIGS.  17 A to  17 C  show two embodiments of a process in which clothes are secondarily dropped and seated from the upper unloading layer  311  to the lower unloading layer  312  in accordance with a time sequence. 
     Referring to  FIGS.  16 A to  16 C , while the clothes are secondarily dropped, a distance from the uppermost end of the loading portion to the upper unloading layer  311 , that is, the secondary drop distance, may maintain a first distance. This means that the height of the lower unloading layer  312  does not change during the secondary dropping. The first distance may be maintained to be relatively narrow or wide, and the advantages according to each state are the same as those described above. 
     Meanwhile, referring to  FIG.  17   , while the clothes are secondarily dropped, the secondary drop distance may gradually increase from a second distance to a third distance. The advantage of this embodiment is that when the clothes are initially seated on the lower unloading layer  312 , the drop distance is maintained to be narrow to prevent unintended wrinkle and when the clothes are finally seated, a space is secured in the height direction so that it is possible to produce the same effect as that of the case where a forward and backward space is expanded. Therefore, combined advantages can be obtained. 
     In order to figure out the secondary drop distance, the clothes folding device  10  may include a load sensor  501 . The load sensor  501  senses the height of the top surface of the lower unloading layer  312  or the height of the uppermost end of the clothes loaded on the lower unloading layer  312 . The load sensor  501  may be implemented in the form of at least one proximity sensor. For example, the load sensor  501  in the form of a proximity sensor is provided near at least one point on the side of the drawer  502 . When the lower unloading layer  312  is located at the corresponding height or when the loaded clothes are located at the corresponding height, the load sensor  501  can recognize it. The above-described at least one point may be located at a height corresponding to a lower boundary value among upper and lower boundary values of the first distance, the second distance, and the third distance. 
       FIG.  18    is a perspective view of the unloading assembly  300  related to the present disclosure. 
     A pressure guide  3111  may be provided on the lower surface of the upper unloading layer  311 . The pressure guide  3111  allows the loaded clothes to be pressed to reduce the volume of the clothes and to more stably maintain the folded state of the clothes. 
     In particular, when the upper unloading layer  311  moves in the forward and backward direction, the pressure guide  3111  can also move together, so that the pressure guide  3111  can selectively press various areas of the loaded clothes. 
     The up and down drive unit  423  may drive such that the uppermost end of the clothes loaded on the lower unloading layer  312  is pressed by the pressure guide  3111 . That is, this drive may include a rising process. When the clothes are seated, the secondary drop distance is sufficiently formed, and when the clothes are seated and loaded, the secondary drop distance is reduced so that the loading portion can be pressurized. The pressing state may be performed temporarily or may be repeatedly performed. 
       FIGS.  19 A and  19 B  are side views of the unloading assembly  300  related to the present disclosure. 
     As described above, the drawer  502  that forms a space in which the folded clothes are stored may have a structure in which the clothes are pulled out. This may be automatically implemented by a drive unit that operates electrically and mechanically, or may be implemented manually by an external force of a user, etc. 
     When the drawer  502  is opened to take out the clothes, the lower unloading layer  312  may be driven such that the uppermost end of the loading portion of the up and down drive unit  423  becomes a predetermined distance “H” from a bottom surface  601 . Accordingly, the user can take out the clothes without bending the back too much. 
     It is apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential characteristics of the present invention. 
     The above detailed description should not be construed as restrictive in all respects and should be considered as illustrative. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present invention are included in the scope of the present invention.