Patent Publication Number: US-2022227509-A1

Title: Inner module structure of auto strapping packaging tool

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2021-0006584, 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. 
     Conventional auto strapping packaging tools have similar exteriors. This is because of a shape of a body housing, configuration of components disposed therein, an arrangement thereof, and the like. In addition, one cylindrical brushless direct current (BLDC) motor is disposed and controlled in the conventional strapping packaging tool. However, since an internal structure according to the conventional technology becomes complex, and high vibration due to linear reciprocating motion 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. In addition, in the conventional auto packaging tool, due to a complex structure, a manufacturing cost is increased, it is difficult to deal with problems, and thus there is a problem in that costs of purchase, maintenance, and the like are increased. 
     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 inner module structure of an auto strapping packaging tool, in which internal components are formed in units of modules so that automatic assembly of a product is realized. 
     In addition, the present invention is directed to improving a conventional complex 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. 
     In addition, the present invention is directed to minimizing an unbalance of internal weight due to components and improving user convenience. 
     In addition, the present invention is directed to maximizing productivity and assemblability by producing and assembling the product in units of modules, decreasing a manufacturing cost of the product, and securing price competitiveness. 
     According to an aspect of the present invention, there is provided an inner module structure of an auto strapping packaging tool, the inner module structure including a tension module in which first power generated by a first dedicated motor disposed at a rear side is transmitted to a front side to provide a tensile force to a packaging plastic band, and a welding module which is disposed at one side of the tension module, and in which a gripper unit is opened or closed by second-1 power due to axial rotation in a forward direction of a second dedicated motor disposed at a rear side in the welding module, and the gripper unit linearly reciprocates by second-2 power due to axial rotation in a reverse direction of the second dedicated motor to provide a friction force to the plastic band to which the tensile force is applied through the tension module, wherein each of the tension module and the welding module is formed in units of modules, and driving of the tension module and the welding module is individually controlled. 
     Each of the first dedicated motor and the second dedicated motor may be a flat motor. 
     The welding module may further include an opening and closing unit which is coupled to an upper portion of the gripper unit and provides vertical movement for the gripper unit to open or close the gripper unit through an operation according to axial rotation when the second-1 power is transmitted, and a belt pully part disposed between the second dedicated motor and the opening and closing unit to transmit the second-1 power between the second dedicated motor and the opening and closing unit. 
     The opening and closing unit may include a first driven shaft which is driven by the second-1 power transmitted by the belt pully part and has a first eccentric element formed on an outer circumferential surface, a head part through which the first driven shaft passes, in which the first eccentric element is in contact with an inner side surface, and which performs cam movement according to axial rotation of the first driven shaft, and a connecting rod part having one end coupled to a lower side of the head part and the other end coupled to the gripper unit to vertically move the gripper unit according to movement of the head part. 
     An elastic member, which buffers vibration generated by linear reciprocating movement of the gripper unit, may be disposed on an outer circumferential surface of the connecting rod part. 
     The gripper unit may include a second driven shaft which is driven by the second-2 power and has a second eccentric element formed on an outer circumferential surface, an inner gripper part in which a half ring piece formed at one end of the inner gripper part is held on the second driven shaft to linearly and slidably reciprocate due to cam movement according to axial rotation of the second driven shaft, and guide protrusions are formed on both side surfaces, and an outer gripper part of which one end is axially rotatably coupled to the second driven shaft, and in which the inner gripper part is accommodated and slidably enters or exits. 
     The outer gripper part may further include protrusion grooves formed in an inner side surface to correspond to the guide protrusions and fastening holes on which parts of upper surfaces are open and to which an end portion of the connecting rod part is axially rotatably coupled. 
     The inner module structure may further include a spur gear part disposed between the second dedicated motor and the gripper unit to transmit the second-2 power between the second dedicated motor and the gripper unit. 
    
    
     
       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 illustrating an inner module structure of an auto strapping packaging tool according to one embodiment of the present invention; 
         FIG. 2  is a plan view of  FIG. 1  when viewed from another direction; 
         FIG. 3  is an exploded perspective view of  FIG. 1 ; 
         FIG. 4  is an exploded perspective view illustrating an opening and closing unit of  FIG. 1 ; 
         FIG. 5  is an exploded perspective view illustrating a gripper unit of  FIG. 1 ; 
         FIGS. 6A and 6B  are a set of views showing a process in which the gripper unit of  FIG. 1  is opened and closed; and 
         FIG. 7  is a view showing a direction in which the gripper unit linearly reciprocates in  FIG. 6B . 
     
    
    
     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 illustrating an inner module structure of an auto strapping packaging tool according to one embodiment of the present invention,  FIG. 2  is a plan view of  FIG. 1  when viewed from another direction,  FIG. 3  is an exploded perspective view of  FIG. 1 ,  FIG. 4  is an exploded perspective view illustrating an opening and closing unit of  FIG. 1 , and  FIG. 5  is an exploded perspective view illustrating a gripper unit of  FIG. 1 . 
     Referring to  FIGS. 1 to 5 , the inner module structure of an auto strapping packaging tool according to one embodiment of the present invention may include a tension module  100 , a welding module  200 , a base plate  300 , and the like. In the auto strapping packaging tool, a tensile force having a predetermined magnitude is applied to a plastic band through the tension module  100  after the packaging plastic band is disposed to wrap 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  200 , and portions of the plastic band, which overlaps itself in two layers, are locally melted and bonded. In this case, the plastic band may be formed of a polypropylene (PP) material, a polyethylene terephthalate (PET) material, or the like. 
     The base plate  300  according to one embodiment may be a portion forming a part of a body housing, particularly, that is, a bottom part. The base plate  300  allows the auto strapping packaging tool to be in surface contact with a flat surface of target goods or a ground surface paper so that the packaging tool is disposed to be perpendicular to the goods and the like. In addition, the base plate  300  may further include at least one holding element to allow various components forming the auto strapping packaging tool to be stably disposed, installed, and fixed. 
     In the tension module  100 , first power generated by a first dedicated motor  110  disposed at a rear side in the tension module  100  is transmitted to a front side so as to provide a tensile force to the packaging plastic band. The tension module  100  is disposed at one side of an upper surface of the base plate  300  and receives a rotational force provided by the first dedicated motor  110  to wrap and pull one end of the plastic band. The tension module  100  may provide the tensile force to the plastic band through an operation of pulling the plastic band in a strapping process. 
     The tension module  100  may include a wheel driven shaft  121  which is disposed in a central portion thereof and axially rotated, a worm gear unit which is a gear assembly disposed on an outer circumference of the wheel driven shaft  121  and engaged with the wheel driven shaft  121  to be rotated at a reduced speed, and the like. In addition, the tension module  100  may further include a feed wheel part  120  which is coupled to an outer circumferential surface of the worm gear unit, is 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  120  has a cylindrical shape, and a knurling part is formed on an outer circumferential surface of the feed wheel part  120 . In addition, a first driving shaft of the first dedicated motor  110  is disposed to be parallel to the wheel driven shaft  121 . In addition, a spur gear, which transmits a rotational force to the wheel driven shaft  121 , is coupled to the first driving shaft. As a result, the first power generated by the first dedicated motor  110  may be transmitted to the feed wheel part  120  through the first driving shaft, the wheel driven shaft  121 , and the worm gear unit. 
     The welding module  200  is disposed at one side of the tension module  100 , a gripper unit  220  is opened or closed by second-1 power caused by axial rotation in a forward (either of clockwise and counter-clockwise) direction of a second dedicated motor  210  disposed at a rear side in the welding module  200 , and the gripper unit  220  linearly reciprocates due to second-2 power caused by axial rotation in the reverse direction of the second dedicated motor  210  to provide the friction force to the plastic band to which the tensile force is applied through the tension module  100 . 
     In this case, the second dedicated motor  210  may provide a first rotational force through the rotation in the forward direction. In addition, the second dedicated motor  210  may provide a second rotational force through the rotation in the reverse direction. Meanwhile, a rotating speed, a rotating time, and the like of the second dedicated motor  210  are controlled by a control part (not shown). The first dedicated motor  110  and the second dedicated motor  210  may be electric motors operated by power provided from the outside (or a power source such as an internal battery). 
     A second driving shaft of the second dedicated motor  210  may be rotated in the forward or reverse direction according to axial rotation. In addition, a principle, a method, an operation, and the like in which the gripper unit  220  is opened or closed by the second-1 power according to one embodiment will be described below. In addition, a principle, a method, an operation, and the like in which the gripper unit  220  linearly reciprocates by the second-2 power according to one embodiment will also be described below. 
     Meanwhile, the first dedicated motor  110  and the second dedicated motor  210  according to one embodiment may be flat motors. In addition, since the first dedicated motor  110  and the second dedicated motor  210  are disposed in the modules, each of the tension module  100  and the welding module  200  is formed in units of modules, and thus driving of the tension module  100  and the welding module  200  may be individually controlled. In addition, since each of the first dedicated motor  110  and the second dedicated motor  210  is disposed at the rear side in the module, a 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. 
     Specifically, the welding module  200  may include the second dedicated motor  210 , the opening and closing unit  240 , the gripper unit  220 , a belt pully part  260 , a spur gear part  280 , and the like. The welding module  200  is disposed at one side of the tension module  100  and provides the friction heat to bond the plastic band disposed in two layers. Meanwhile, although not illustrated in the drawings, all or some of units, components, and the like included in the welding module  200  may be installed, held, and fixed using the above-described holding elements. 
     A bevel gear is coupled to the second driving shaft of the second dedicated motor  210 . Meanwhile, due to an arrangement direction of the second dedicated motor  210 , the packaging tool according to one embodiment may further include a spur gear part  280  disposed between the second dedicated motor  210  and the gripper unit  220  to transmit the second-2 power therebetween. The spur gear part  280  may include 1) a first connecting shaft  281  on which a bevel gear and a spur gear are coupled to an outer circumferential surface thereof, and which is perpendicularly engaged with the second driving shaft by the bevel gear and 2) a second connecting shaft  282  which is disposed to be parallel to the first connecting shaft, and to which a spur gear engaged with the spur gear of the first connecting shaft is coupled to be driven by a rotational force of the first connecting shaft. The spur gear part  280  may include the first connecting shaft  281  perpendicularly engaged with the second driving shaft. 
     In this case, a one-way clutch bearing may be coupled to the first connecting shaft  281 . As a result, in a case in which the second dedicated motor  210  provides the second-1 power in the forward direction, the second-1 power is blocked from being transmitted to the gripper unit  220  through the spur gear part  280 . 
     The belt pully part  260  is disposed between the second dedicated motor  210  and the opening and closing unit  240  to transmit the second-1 power therebetween. The belt pully part  260  may include 1) a first pully  261  including a first pully shaft in which a bevel gear is coupled to an outer circumferential surface, and to which the second driving shaft is perpendicularly engaged, 2) a second pully  262  disposed to be parallel to the first pully, and 3) a belt  263  coupled to outer circumferential surfaces of the first pully and the second pully. The belt pully part  260  may include the first pully shaft perpendicularly engaged with the second driving shaft of the second dedicated motor  210 . 
     In this case, the one-way clutch bearing may be coupled to the first pully shaft. As a result, in a case in which the second dedicated motor  210  provides the second-2 power in the reverse direction, the second-2 power is blocked from being transmitted to the opening and closing unit  240  through the belt pully part  260 . 
     The opening and closing unit  240  is coupled to an upper portion of the gripper unit  220 , and when the second-1 power is transmitted, the opening and closing unit  240  provides vertical movement for the gripper unit  220  to open or close the gripper unit  220  through an operation according to axial rotation. The opening and closing unit  240  may include a first driven shaft  241 , a head part  243 , a connecting rod part  244 , an elastic member  245 , and the like. In the opening and closing unit  240 , when the first driven shaft  241  disposed at an upper end thereof rotates, the connecting rod part  244  is moved downward, and the gripper unit  220  is pressed by the connecting rod part  244 . In this case, the plastic band disposed in two layers between an inner gripper part  223  and a lower gripper part  229  is pressed. The opening and closing unit  240  may be driven by the second dedicated motor  210 . 
     The first driven shaft  241  is driven by the second-1 power transmitted by the belt pully part  260 , and a first eccentric element  242  is formed on an outer circumferential surface of the first driven shaft  241 . In this case, one end of the first driven shaft  241  is fitted to the second pully. The first driven shaft  241  passes through the head part  243 , the first eccentric element  242  is in contact with an inner surface of the head part  243 , and the head part  243  performs cam movement according to axial rotation of the first driven shaft  241 . One end of the connecting rod part  244  is coupled to a lower side of the head part  243 , and the other end thereof is coupled to the gripper unit  220  to vertically move the gripper unit  220  according to the movement of the head part  243 . In addition, an elastic member  245 , which buffers vibration generated due to linear reciprocating movement of the gripper unit  220 , may be disposed on an outer circumferential surface of the connecting rod part  244 . 
     The second-1 power generated by the second dedicated motor  210  is finally transmitted to the gripper unit  220  through the second driving shaft, the belt pully part  260 , the first driven shaft  241 , the head part  243 , and the connecting rod part  244 . In this case, the second-1 power is blocked from being transmitted to the gripper unit  220  by the one-way clutch bearing coupled to the spur gear part  280 . 
     The gripper unit  220  may include a second driven shaft  221 , an inner gripper part  223 , an outer gripper part  226 , the lower gripper part  229 , and the like. The second driven shaft  221  is driven by the second-2 power, and a second eccentric element  222  is formed on an outer circumferential surface of the second driven shaft  221 . Meanwhile, a spur gear  230  engaged with the spur gear part  280  is coupled to one end of the second driven shaft  221 . 
     As a half ring piece  224  formed at one end of the inner gripper part  223  is held on the second driven shaft  221 , the inner gripper part  223  linearly and slidably reciprocates due to cam movement according to axial rotation of the second driven shaft  221 , and guide protrusions  225  are formed on both side surfaces of the inner gripper part  223 . The inner gripper part  223  is moved downward by the opening and closing unit  240  and linearly reciprocates due to the second-2 power generated by the second dedicated motor  210  within a predetermined stroke. That is, the inner gripper part  223  vibrates. Meanwhile, a knurling plate may be formed on a lower surface of the inner gripper part  223 . 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  226  is axially rotatably coupled to the second driven shaft  221 , and the inner gripper part  223  may be accommodated in the outer gripper part  226  and may slidably enter or exit the outer gripper part  226 . To this end, the outer gripper part  226  may further include protrusion grooves  227  formed in an inner side surface thereof to correspond to the guide protrusions  225  and fastening holes  228  on which parts of upper surfaces are open so that an end portion of the connecting rod part  244  is axially rotatably coupled. The lower gripper part  229  is disposed at a position facing a lower side of the inner gripper part  223 . Meanwhile, a knurling plate is also formed on an upper surface of the lower gripper part  229 . 
     Meanwhile, the second-2 power generated by the second dedicated motor  210  is finally transmitted to the inner gripper part  223  through the second driving shaft, the spur gear part  280 , and the second driven shaft  221 . In this case, the second-2 power is blocked from being transmitted to the opening and closing unit  240  by the one-way clutch bearing coupled to the belt pully part  260 . Meanwhile, the welding module  200  may further include a cutting unit (not shown) which is moved downward in conjunction with downward movement of the opening and closing unit  240  to cut the plastic band. 
       FIGS. 6A and 6B  are a set of views showing a process in which the gripper unit of  FIG. 1  is opened and closed. Referring to  FIG. 6A , the gripper unit  220  is disposed at a predetermined inclination angle with respect to the base plate  300  (or the lower gripper part  229 ). The gripper unit  220  is in an open state. When the plastic band receives the tensile force through the tension module  100 , the second-1 power due to axial rotation of the second dedicated motor  210  is transmitted through the opening and closing unit  240 . In this case, the connecting rod part  244  moves the gripper unit  220  in a downward direction through axial rotation of the first driven shaft  241 . The connecting rod part  244  is coupled to the outer gripper part  226 , and the outer gripper part  226  may be axially rotated about the second driven shaft  221  by downward pressurization so that the outer gripper part  226  may be disposed to be parallel to the lower gripper part  229  (see  FIG. 6B ). 
     Since each of the tension module  100  and the welding module  200  according to one embodiment is formed in units of modules, driving thereof is individually controlled. That is, the tension module  100  and the welding module  200  are completely separated and independently operated. Therefore, the productivity is improved, and the assembly efficiency is maximized. 
     A strapping process performed by the auto strapping packaging tool will be described below. First, the plastic band receives the tensile force having a magnitude preset by the first power generated by the first dedicated motor  110 . Accordingly, the tensile force providing process is completed. Then, the welding module  200  operates for welding. A welding process is started by an operation of the opening and closing unit  240 . In this process, when the connecting rod part  244  is moved downward by the second-1 power generated by the second dedicated motor  210 , the gripper unit  220  in the open state (see  FIG. 6A ) is switched to a closed state. Then, the gripper unit  220  linearly reciprocates due to the second-1 power generated by the second dedicated motor  210  to provide the friction force to the plastic band provided through the tension module  100 . As a result, the plastic band, which overlaps itself in two layers, disposed between the inner gripper part  223  and the lower gripper part  229  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 inner module structure of an auto strapping packaging tool according to one embodiment of the present invention, since internal components are formed in units of modules, automatic assembly of a product can be realized. 
     In addition, in the present module structure, a conventional complex structure can be effectively improved by substituting motors with a new kind of motor and newly designing a designated motor that is disposed in each module. 
     In addition, in the present module structure, an unbalance of internal weigh can be minimized to improve user convenience. 
     In addition, the present module structure can maximize productivity and assemblability, decrease a manufacturing cost of the product, and secure price competitiveness by producing and assembling a product in units of modules. 
     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.