Patent Publication Number: US-2022227508-A1

Title: Auto strapping packaging tool having clamp fixing apparatus

Description:
This application claims priority to and the benefit of Korean Patent Application No. 10-2021-0006578, filed on Jan. 18, 2021 the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates to an auto strapping packaging tool, and more particularly, to an auto strapping packaging tool used when packaging goods and the like using a plastic band. 
     2. Discussion of Related Art 
     Auto strapping packaging tools have portable tool types and are used to package goods such as boxes using plastic bands. Packaging is performed by wrapping goods using a plastic band to form a loop and tightening the plastic band using an auto packaging tool until a predetermined magnitude of tension is generated on the loop. Then, a subsequent process is performed by bonding portions of the plastic band which overlaps itself in two layers. In this case, the bonding is mainly performed by using friction heat generated by vibrating the plastic band in a state in which the plastic band is pressed. Accordingly, solid bonding between homogeneous materials is performed on the plastic band in a locally molten state. Then, when the bonded portions are cooled, a solid loop is formed. 
     In the conventional auto strapping packaging tool, there is cumbersomeness in continuously maintaining a state, in which a clamp is spaced apart from a feed wheel by a predetermined distance, in a process of wrapping a plastic band, which is a first operation of strapping. Therefore, it is inconvenient for a user to work, and when the work lasts for a long time, there is a problem of reducing work convenience. 
     In addition, one cylindrical brushless direct current (BLDC) motor is disposed and controlled in the conventional strapping packaging tool. Accordingly, since an internal structure becomes complex and high vibration is transmitted to other apparatuses in a welding process, there is a problem of badly affecting the durability of internal components. In addition, since a layout of the components is limited due to the long cylindrical BLDC motor, an unbalance occurs in the overall weight distribution, and thus inconvenience is raised in terms of usability. 
     PRIOR ART 
     Patent Document 
     
         
         (Patent Document 1) Korean Patent Registration No. 10-1675003 (registered on Nov. 4, 2016) “STRAPPING DEVICE WITH A GEAR SYSTEM DEVICE” 
         (Patent Document 2) Korean Patent Registration No. 10-1613247 (registered on Apr. 11, 2016) “STRAPPING DEVICE WITH A TENSIONER” 
         (Patent Document 3) Korean Patent Publication No. 10-2019-0034662 (published on Apr. 2, 2019) “STRAPPING APPARATUS” 
       
    
     SUMMARY OF THE INVENTION 
     The present invention is directed to providing an auto strapping packaging tool having a clamp fixing apparatus which has an open mode and a closed mode. In addition, the present invention is directed to providing a structure in which switching may be performed between the modes by a simple manipulation of a user. In addition, the present invention is directed to providing a structure in which a clamp may be stably fixed in the open mode. 
     In addition, the present invention is directed to improving a complex conventional structure by substituting a conventional motor with a motor having a new type and newly designing a dedicated motor to be disposed in each module. Accordingly, the present invention is directed to minimizing an unbalance of internal weigh and improving user convenience. 
     According to an aspect of the present invention, there is provided an auto strapping packaging tool having a clamp fixing apparatus, the auto strapping packaging tool including a body assembly, a tension module which is partially coupled to the body assembly and provides a tensile force to a plastic band using a first motor, a feed wheel part rotated by the first motor about a first shaft, and a clamp part disposed around the feed wheel part and rotated about a second shaft, a welding module which includes a second motor and a third motor and provides a friction force to the plastic band to which the tensile force is applied by the tension module, a hooking part provided with a first hooking element axially rotatably disposed in the body assembly and a second hooking element fixedly disposed in the body assembly, and a lever unit which is axially rotatably coupled to the body assembly and switched to an open mode while a position thereof is fixed by being hooked on the first hooking element when a pulling operation of a user is applied thereto. 
     In a process in which the lever unit is switched to the open mode, the clamp part may be axially rotated around the feed wheel part to be opened. 
     The lever unit may include a lever body having a handle formed on one end thereof, and a shaft hole formed in the other end to be axially rotatable, a first hooking piece which extends outward from the lever body and has a hooking step formed on an end portion thereof, and an extension hooking member coupled to the other end of the lever body and released from hooking on the second hooking element when the lever unit is switched to the open mode. 
     The tension module may further include an annular ring portion which is coupled to the feed wheel part to be rotated about the first shaft and has a first tooth formed on a part thereof and a protruding piece formed on another part thereof in a radial direction. 
     A connecting piece having one end connected to an end portion of a lever shaft and the other end in which a second tooth engaged with the first tooth is formed, may be disposed between the lever unit and the tension module. 
     The first hooking element may include a pressing button bar pressed by the user and coupled to the first hooking element so that the first hooking element is axially rotated. 
     The first hooking element may have a cylindrical shape, and a plurality of hooking steps disposed to be spaced apart from each other in one direction may be formed on an outer circumferential surface of the first hooking element. 
     The welding module may include a friction providing unit which is disposed in the body assembly and linearly reciprocates due to second power generated by the second motor to provide the friction force to the plastic band to which the tensile force is applied by the tension module, and an opening and closing unit which has one end coupled to the friction providing unit, performs link movement due to third power generated by the third motor to provide vertical movement for the friction providing unit, and opens or closes the friction providing unit through an operation according to axial rotation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing exemplary embodiments thereof in detail with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view of an auto strapping packaging tool having a clamp fixing apparatus according to one embodiment of the present invention; 
         FIG. 2  is a plan view of  FIG. 1  when viewed from above; 
         FIG. 3  is an exploded perspective view of  FIG. 1 ; 
         FIG. 4  is an exploded perspective view illustrating a lever unit of  FIG. 1 ; 
         FIG. 5  is an exploded perspective view illustrating a welding module of  FIG. 1 ; 
         FIGS. 6A to 6C  are a set of views showing a process in which a clamp part is fixed by an operation of the hooking part and the lever unit of  FIG. 1 ; and 
         FIGS. 7A and 7B  are a set of views showing rotation of the clamp part in the process of  FIG. 6A to 6C . 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, when the present invention is described, in a case in which it is determined that the detailed descriptions of related technologies well-known to those skilled in the art unnecessarily obscure the gist of the invention, the detailed descriptions will be omitted. The terminologies used herein are for the purpose of describing particular embodiments only and are not intended to be limiting to the invention. As used herein, the singular forms “a,” “an,” and “the” 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/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     Hereinafter, a specific embodiment of the present invention will be described in detail with reference to the accompanying drawings. 
       FIG. 1  is a perspective view of an auto strapping packaging tool having a clamp fixing apparatus according to one embodiment of the present invention,  FIG. 2  is a plan view of  FIG. 1  when viewed from above, and  FIG. 3  is an exploded perspective view of  FIG. 1 . Referring to  FIGS. 1 to 3 , the auto strapping packaging tool including the clamp fixing apparatus according to one embodiment of the present invention may include a body assembly  100 , a tension module  200 , a welding module  300 , a hooking part  400 , a lever unit  500 , and the like. 
     In the auto strapping packaging tool, a tensile force having a predetermined magnitude is applied to a plastic band by the tension module  200  after the packaging plastic band is disposed to wrap around goods. In addition, in the auto strapping packaging tool, the plastic band receives friction heat caused by vibration in a state in which the plastic band is pressed by the welding module  300 , and portions of the plastic band, which overlaps itself in two layers, are locally melted so that the portions are bonded. In this case, the plastic band may be formed of a polypropylene (PP) material, a polyethylene terephthalate (PET) material, or the like. 
     The body assembly  100  according to one embodiment may include a part of a body housing. The body assembly  100  allows internal components, for example, the tension module  200 , to be stably disposed in the body housing. In the body assembly  100 , the hooking part  400  and the like are installed and provide uses and functions. In addition, the body assembly  100  is formed in a shape designed in advance to provide systematic relationships between the internal components and smooth implementation of the functions therethrough. 
     The tension module  200  is partially coupled to the body assembly  100  and provides a tensile force to the plastic band through a first motor  210 , a feed wheel part  220  which is rotated about a first shaft a 1  by the first motor  210 , and a clamp part  230  which is disposed around the feed wheel part  220  and rotated about a second shaft a 2 . The tension module  200  receives a rotational force provided by the first motor  210  to wrap and pull one end of the plastic band. The tension module  200  may provide the tensile force to the plastic band through the operation of pooling the plastic band in a strapping process. 
     The tension module  200  may include the first shaft a 1  which is disposed at a central portion and axially rotated, a worm gear unit which is a gear assembly disposed on an outer circumference of the first shaft a 1 , engaged with the first shaft a 1 , and rotated at a reduced speed, and the like. In addition, the tension module  200  may further include the feed wheel part  220  which is coupled to an outer circumferential surface of the worm gear unit and rotated therewith and wraps and pulls the plastic band using a friction force caused by pressurization, and the like. In this case, the feed wheel part  220  has a cylindrical shape, and a knurling portion is formed on an outer circumferential surface thereof. In addition, the first motor  210  is disposed in a rear portion in the tension module  200 . A first driving shaft of the first motor  210  is disposed to be parallel to the first shaft a 1 . A spur gear, which transmits a rotational force to the first shaft a 1 , is coupled to the first driving shaft. As a result, first power generated by the first motor  210  may be transmitted to the feed wheel part  220  through the first driving shaft, the first shaft a 1 , and the worm gear unit. 
     Meanwhile, the tension module  200  may further include an annular ring portion  240  which is coupled to the feed wheel part  220  and is rotated about the first shaft a 1 , and on which a first tooth  241  is formed on one part thereof, and a protruding piece  242  is formed on another part thereof in a radial direction. The annular ring portion  240  has a ring shape and reciprocates within a predetermined angular range by a connecting piece  610  when coupled to the feed wheel part  220 . 
     The clamp part  230  has substantially an “L” shape and rotates about the second shaft a 2 . A curved knurling portion may be formed on the clamp part  230  to correspond to the knurling portion. In addition, a groove, in which the protruding piece  242  is accommodated and coupled thereto, is formed in an end of the clamp part  230 . As a result, the clamp part  230  is rotated about the second shaft a 2  according to rotation due to the annular ring portion  240 . For example, when a pulling operation of a user is applied to the lever unit  500 , the clamp part  230  is separated from the feed wheel part  220 , and the plastic band may be inserted into a gap therebetween. Conversely, when the pulling operation is released so that the lever unit  500  moves in an opposite direction, the clamp part  230  becomes close to the feed wheel part  220 . 
       FIG. 4  is an exploded perspective view illustrating the lever unit of  FIG. 1 , and  FIG. 5  is an exploded perspective view illustrating the welding module of  FIG. 1 . The welding module  300  includes a second motor  311  and a third motor  351  and provides a friction force to the plastic band to which the tensile force is applied by the tension module  200 . As described above, the auto strapping packaging tool includes the first motor  210  to the third motor  351 . In this case, rotating speeds, rotating times, and the like of the first motor  210  to the third motor  351  are controlled by a control part (not shown). The first motor  210  to the third motor  351  may be electric motors operated by power provided from the outside (or a power source such as an internal battery). 
     The welding module  300  is disposed at one side of the tension module  200  and provides friction heat to bond the plastic band disposed in two layers. Meanwhile, although units, components, and the like included in the welding module  300  are not illustrated in the drawings, all or some thereof may be installed, held, and fixed using the above-described holding elements. 
     Specifically, the welding module  300  may include a friction providing unit  310  which is disposed in the body assembly  100  and linearly reciprocates due to second power generated by the second motor  311  to provide the friction force to the plastic band to which the tensile force is applied by the tension module  200  and an opening and closing unit  350  having one end coupled to the friction providing unit  310 , and performing link movement caused by third power generated by the third motor  351  to provide vertical movement for the friction providing unit  310  and open or close the friction providing unit  310  through an operation according to axial rotation. 
     In addition, since the first motor  210  to the third motor  351  are disposed in modules, each of the tension module  200  and the welding module  300  are formed in units of modules, and thus, driving of the first motor  210  to the third motor  351  may be individually controlled. In addition, the first motor  210  to the third motor  351  are disposed in rear portions in the modules, and thus the weight of the auto strapping packaging tool may be easily distributed. This is a difference from an inner layout of a conventional auto strapping packaging tool and may improve user convenience. That is, since the weight applied to the auto strapping packaging tool may be effectively distributed, even when the user performs packaging work for a long time, there is no strain on a wrist joint and the like. 
     A bevel gear is coupled to a second driving shaft of the second motor  311 . Meanwhile, due to an arrangement direction of the second motor  311 , the welding module  300  according to one embodiment may further include a spur gear part  330  disposed between the second motor  311  and the friction providing unit  310  to transmit the second power therebetween. The spur gear part  330  may include 1) a first connecting shaft on which the bevel gear and the spur gear are coupled to an outer circumferential surface and which is perpendicularly engaged with the second driving shaft by the bevel gear, and 2) a second connecting shaft which is disposed to be parallel to the first connecting shaft and to which a spur gear engaged with a spur gear of the first connecting shaft is coupled so that the second connecting shaft is driven by a rotational force of the first connecting shaft. 
     The friction providing unit  310  may include the second motor  311 , a second driven shaft  321 , an inner gripper part  323 , an outer gripper part  326 , a lower gripper part  329 , and the like. The second driven shaft  321  is driven by the second power, and a second eccentric element  322  is formed on an outer circumferential surface of the second driven shaft  321 . Meanwhile, a spur gear engaged with the spur gear part  330  is coupled to one end of the second driven shaft  321 . 
     A half ring piece  324  formed on one end of the inner gripper part  323  is held on the second driven shaft  321  so that the inner gripper part  323  linearly and slidably reciprocates by a cam movement according to axial rotation of the second driven shaft  321 , and guide protrusions  325  are formed on both side surfaces of the inner gripper part  323 . The inner gripper part  323  is moved downward by the opening and closing unit  350  and linearly reciprocates within a predetermined stroke due to the second power of the second motor  311 . That is, the inner gripper part  323  vibrates. Meanwhile, a knurling plate may be formed on a lower surface of the inner gripper part  323 . Grooves are repeatedly formed in a lateral or diagonal direction to have a predetermined pattern in the knurling plate. 
     One end of the outer gripper part  326  is axially rotatably coupled to the second driven shaft  321 , and the inner gripper part  323  may be accommodated in the outer gripper part  326  and may slidably enter or exit the outer gripper part  326 . To this end, the outer gripper part  326  may further include protrusion grooves  327  formed in inner side surfaces thereof to correspond to the guide protrusions  325  and a coupling hole  328  on which a part of an upper surface is open, and to which an end portion of a connecting rod part  356  is axially rotatably coupled. The lower gripper part  329  is disposed at a position facing a lower side of the inner gripper part  323 . Meanwhile, a knurling plate is also formed on an upper surface of the lower gripper part  329 . 
     Meanwhile, the second power generated by the second motor  311  is finally transmitted to the inner gripper part  323  through the second driving shaft, the spur gear part  330 , and the second driven shaft  321 . Meanwhile, the welding module  300  may further include a cutting unit (not shown) which is moved downward in conjunction with downward movement of the opening and closing unit  350  to cut the plastic band. 
     The opening and closing unit  350  is coupled to an upper portion of the friction providing unit  310 , and when the third power is transmitted thereto, the opening and closing unit  350  provides vertical movement for the friction providing unit  310  to open or close the friction providing unit  310  through the operation according to axial rotation. The opening and closing unit  350  may include the third motor  351 , an eccentric driving shaft  352 , a link part  354 , a connecting rod part  356 , an elastic member  358 , an opening and closing unit holding element  359 , and the like. The eccentric driving shaft  352  is disposed at the other end of the third motor  351  to be eccentric to one side. 
     When the eccentric driving shaft  352  disposed at an upper end of the opening and closing unit  350  rotates, the connecting rod part  356  is moved downward, and the friction providing unit  310  is pressed by the connecting rod part  356 . In this case, the plastic band disposed in two layers between the inner gripper part  323  and the lower gripper part  329  is pressed. 
     One end of the link part  354  is coupled to an end portion of the eccentric driving shaft  352 . The link part  354  performs cam movement according to axial rotation of the eccentric driving shaft  352 . One end of the connecting rod part  356  is coupled to the link part  354 , and the other end thereof is coupled to the friction providing unit  310  to vertically move the friction providing unit  310  according to rotation of the eccentric driving shaft  352 . In addition, the elastic member  358 , which buffers vibration generated by linear reciprocating movement of the friction providing unit  310 , may be disposed on an outer circumferential surface of the connecting rod part  356 . The third power generated by the third motor  351  is finally transmitted to the friction providing unit  310  through the eccentric driving shaft  352 , the link part  354 , and the connecting rod part  356 . 
     The hooking part  400  is composed of a first hooking element  410  axially rotatably disposed on the body assembly  100  and a second hooking element  420  fixedly disposed on the body assembly  100 . Specifically, the first hooking element  410  has a cylindrical shape, and a plurality of hooking steps disposed to be spaced apart from each other in one direction are formed on an outer circumferential surface of the first hooking element  410 . In addition, the first hooking element  410  may include a pressing button bar  411  which is pressed by the user and coupled to the first hooking element  410  so that the first hooking element  410  is axially rotated. In addition, the first hooking element  410  may include a torsion spring that is compressed in the direction of axial rotation when the pressing button bar  411  is pressed. 
     The second hooking element  420  is fixedly disposed in the body assembly  100 . Specifically, the second hooking element  420  has a cylindrical shape, and a plurality of hooking steps disposed to be spaced apart from each other in one direction are formed on an outer circumferential surface of the second hooking element  420 . A shape of the second hooking element  420  may be the same as or similar to that of the first hooking element  410 . 
     The lever unit  500  is axially rotatably coupled to the body assembly  100 , and when the pulling operation is applied to the lever unit  500  by the user, the lever unit  500  is hooked on the first hooking element  410  so that a position thereof is fixed, and the lever unit  500  is switched to an open mode. Meanwhile, in the process in which the lever unit  500  is switched to the open mode, the clamp part  230  axially rotates around the feed wheel part  220  to be opened. In the open mode, a hooking step of a first hooking piece  520  is hooked on the first hooking element  410  so that a lever body  510  is fixed at that position. In this case, a lever shaft  531  is also rotated by the same angle to rotate the annular ring portion  240  through the connecting piece  610 . As a result, the clamp part  230  is separated from the feed wheel part  220 , fixed in that state, and opened. 
     Specifically, the lever unit  500  may include the lever body  510 , the first hooking piece  520 , an extension hooking member  530 , and the like. A handle is formed on one end of the lever body  510 , and a shaft hole  511  is formed in the other end thereof so that the lever body  510  is axially rotatable. In addition, a coil spring is disposed in the lever body  510 . The lever body  510  is rotated by a predetermined angle by the pulling operation of the user, and when the pulling operation is released in that state, the lever body  510  is returned to an original position due to an elastic restoring force of the coil spring. The first hooking piece  520  extends outward from the lever body  510 , and a hooking step is formed on an end portion of the first hooking piece  520 . 
     The extension hooking member  530  is coupled to the other end of the lever body  510 , and when the lever unit  500  is switched to the open mode, the extension hooking member  530  is released from hooking on the second hooking element  420 . Conversely, the lever body  510  is switched to a closed mode from the open mode, the extension hooking member  530  is hooked on and coupled to the second hooking element  420 . The extension hooking member  530  is rotated by the same angle in conjunction with rotation of the lever body  510 . The extension hooking member  530  may include a member body, the lever shaft  531  which is formed on one side surface of the member body and passes through and is coupled to the shaft hole  511 , and a second hooking piece  532  which extends outward from the member body and in which a hooking step is formed on an end portion thereof. 
     Meanwhile, the connecting piece  610  having one end coupled to an end portion of the lever shaft  531  and the other end in which a second tooth engaged with the first tooth  241  is formed, may be disposed between the lever unit  500  and the tension module  200 . The connecting piece  610  is rotated by a predetermined angle to correspond to rotation of the lever shaft  531 . When the connecting piece  610  rotates, the annular ring portion  240  engaged with the connecting piece  610  is also rotated. 
       FIGS. 6A to 6C  are a set of views showing a process in which the clamp part is fixed by an operation of the hooking part and the lever unit of  FIG. 1 , and  FIGS. 7A and 7B  are a set of views showing rotation of the clamp part in the process of  FIG. 6A to 6C . In  FIG. 6A , the second hooking piece  532  of the lever unit  500  is hooked on the second hooking element  420 . In this case, the clamp part  230  is close to (or partially in contact with) the feed wheel part  220  as in  FIG. 7B . This is referred to as the closed mode. First, a process in which the plastic band is inserted into the tension module  200  is performed for strapping. Referring to  FIGS. 6B and 6C , first, the user presses the pressing button bar  411  to rotate the first hooking element  410  to a predetermined angle. Then, the user applies the pulling operation to the lever body  510  so that the end portion, that is, the hooking step, of the first hooking piece  520  is hooked on and coupled to the first hooking element  410 . 
     In this case, even when the user releases the pulling operation from the lever body  510 , the lever body  510  maintains the hooked state. In addition, the extension hooking member  530  is rotated in conjunction with the pulling operation for the lever body  510 , and as a result, the second hooking piece  532  is released from hooking on the second hooking element  420 . 
     In addition, the clamp part  230  rotates about the second shaft a 2  in conjunction with the pulling operation for the lever body  510 . As a result, as illustrated in  FIG. 7A , the clamp part  230  is separated and moved away from the feed wheel part  220 , and the clamp part  230  is fixed in that state. That is, the closed mode is switched to the open mode. In this case, the plastic band may be inserted into the tension module  200 . Specifically, the connecting piece  610  rotates the annular ring portion  240  engaged therewith, and the annular ring portion  240  rotates the clamp part  230  using the protruding piece  242 . 
     Meanwhile, in order to switch the open mode to the closed mode, the user presses the first hooking piece  520  in a downward direction. In this case, the first hooking element  410  is rotated by a predetermined angle, and the lever unit  500  is returned to an original position by an elastic restoring force of the coil spring. Meanwhile, in the above-described process, the connecting piece  610  rotates the annular ring portion  240  in a reverse direction. As a result, the clamp part  230  becomes close to (or is partially in contact with) the feed wheel part  220 . 
     Since the tension module  200  and the welding module  300  according to one embodiment are formed in units of modules, driving thereof is individually controlled. That is, the tension module  200  and the welding module  300  are completely separated and independently operated. Therefore, the productivity is improved, and assembly efficiency is maximized. 
     A strapping process performed by the auto strapping packaging tool will be described below. First, the plastic band receives a tensile force having a magnitude preset by the first power generated by the first motor  210 . Accordingly, the tensile force providing process is completed. Then, the welding module  300  is operated for welding. A welding process is started by an operation of the opening and closing unit  350 . In this process, when the connecting rod part  356  is moved downward by the third power generated by the third motor  351 , the friction providing unit  310  in the open state is switched to the closed state. Then, the friction providing unit  310  linearly reciprocates due to the second power generated by the second motor  311  to provide a friction force to the plastic band provided through the tension module  200 . As a result, the plastic band, which overlaps itself in two layers, disposed between the inner gripper part  323  and the lower gripper part  329  is locally melted and two layers are bonded. 
     According to a solution of the objectives of the present invention, various effects including the following contents can be expected. However, the present invention is not implemented only when all of the following effects are acquired. 
     In an auto strapping packaging tool having a clamp fixing apparatus according to one embodiment of the present invention, an open mode and a closed mode for a clamp can be switched by a simple manipulation of a user. 
     In the auto strapping packaging tool including the clamp fixing apparatus according to one embodiment of the present invention, there are the open mode and the closed mode. In addition, switching between the modes can be performed by the simple manipulation of the user. In addition, the clamp can be stably fixed in the open mode. 
     In addition, by substituting a conventional motor with new kinds of motors and newly designing a designated motor being disposed in each module, a complex conventional structure can be effectively improved. Therefore, an unbalance of internal weigh can be minimized to improve user convenience. 
     Although an example of the exemplary embodiment of the present invention has been described, the scope of the present invention is not limited to the specific embodiment and may be properly changed within the range described in the claims.