Abstract:
An electronic part mounting method including introducing electronic parts in a bulk form into a bulk feeder, transferring the introduced electronic parts to at least one inspection unit by use of a rotatably installed positioning wheel, inspecting and aligning the electronic parts, transferring the inspected and aligned electronic parts to a part insertion unit by use of the positioning wheel, inserting the electronic parts, determined as good ones by the inspection unit, into the part insertion unit, and picking up the electronic parts received in the part insertion unit to mount the electronic parts on a board.

Description:
[0001]    This application is a divisional of U.S. application Ser. No. 12/850,605, filed Aug. 4, 2010, which claims the benefit of Korean Patent Application No. P2009-0071603, filed on Aug. 4, 2009, each of which is hereby incorporated by reference as if fully set forth herein. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an apparatus and method for mounting electronic parts, which are capable of reducing costs. 
         [0004]    2. Discussion of the Related Art 
         [0005]    Generally, once a supplier provides a manufacturer with electronic parts, the manufacturer mounts the electronic parts on a printed circuit board by use of an electronic part mounting apparatus. 
         [0006]    More specifically, a supplier should perform die bonding, wire bonding, and dispensing processes on electronic parts and then, classify the electronic parts according to voltage, brightness, and color coordinate, and finally, pack the classified electronic parts by reel taping. 
         [0007]    A manufacturer performs a sampling test on the electronic parts provided from the supplier, prior to introducing the electronic parts into an electronic part mounting apparatus. To mount the electronic parts on a printed circuit board, the electronic part mounting apparatus should first remove a tape attached to the introduced electronic parts. 
         [0008]    As described above, the supplier should invest in material preparation and handling, labor costs, equipment costs, and construction of a clean room for the reel taping of electronic parts and the packing of the taped electronic parts, thus suffering from enormous investment costs. Likewise, the manufacturer should invest in material preparation and handling, labor costs, equipment costs, and construction of a clean room to remove tapes from the electronic parts, thus suffering from enormous investment costs. 
       SUMMARY OF THE INVENTION 
       [0009]    Accordingly, the present invention is directed to an apparatus and method for mounting electronic parts that substantially obviate one or more problems due to limitations and disadvantages of the related art. 
         [0010]    An object of the present invention is to provide an apparatus and method for mounting electronic parts, which are capable of reducing costs. 
         [0011]    Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
         [0012]    To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, an electronic part mounting apparatus includes a bulk feeder into which electronic parts in a bulk form are introduced, at least one inspection unit to inspect and align the electronic parts directed from the bulk feeder, an electronic part insertion unit to receive the electronic parts which have been completely inspected in the inspection unit, a positioning wheel installed to rotate along the bulk feeder, the inspection unit, and the electronic part inspection unit and serving to transfer the electronic parts, and a part supply unit to pick up the electronic parts received in the part insertion unit. 
         [0013]    The bulk feeder may include a bowl shaped first feeder into which the electronic parts in a bulk form, classified according to a predetermined standard, are introduced, and a straight second feeder located between an outermost end of the first feeder and the positioning wheel. 
         [0014]    The first feeder may include an air blower to provide the electronic parts with air in order to align the electronic parts based on orientation of front and rear surfaces thereof. 
         [0015]    The at least one inspection unit may include a measurement unit to determine whether the electronic parts fed from the bulk feeder are defective or good, a defective part discharge unit to discharge the electronic parts determined as defective ones by the measurement unit, and a polar alignment unit to rotate or invert each electronic part to align polarity of the electronic part. 
         [0016]    The polar alignment unit may determine whether to rotate or invert the electronic part according to whether the electronic part responds to a voltage applied thereto or not, or according to information acquired by comparing image information of the electronic part with image information stored in a database. 
         [0017]    The positioning wheel may include a plurality of suction nozzles to suction and hold the electronic parts, and a basis shaft to be rotated so as to rotate the suction nozzles. 
         [0018]    The electronic part insertion unit may include a carrier tape having a recessed pocket such that each electronic part is inserted into the pocket, and a guide rail to transfer the carrier tape, in which the electronic part has been received, to the part supply unit. 
         [0019]    In accordance with another aspect of the present invention, an electronic part mounting method includes introducing electronic parts in a bulk form into a bulk feeder, transferring the introduced electronic parts to at least one inspection unit by use of a rotatably installed positioning wheel, inspecting and aligning the electronic parts, transferring the inspected and aligned electronic parts to a part insertion unit by use of the positioning wheel, inserting the electronic parts, determined as good ones by the inspection unit, into the part insertion unit, and picking up the electronic parts received in the part insertion unit to mount the electronic parts on a board. 
         [0020]    The introduction of the electronic parts in a bulk form into the bulk feeder may include feeding the electronic parts, classified according to a predetermined standard, into a bowl shaped first feeder, and feeding the electronic parts fed into the first feeder to a straight second feeder located between an outermost end of the first feeder and the positioning wheel. 
         [0021]    The electronic part mounting method may further include providing the electronic parts with air in order to align the electronic parts fed into the first feeder based on orientation of front and rear surfaces thereof. 
         [0022]    The inspection and alignment of the electronic parts may include determining whether the electronic parts fed from the bulk feeder are defective or good, discharging the electronic parts determined as defective ones, and rotating or inverting each electronic part to align polarity of the electronic part. 
         [0023]    With use of an electronic part mounting apparatus and electronic part mounting method according to the present invention, once electronic part packages are classified according to a predetermined standard, the electronic part packages in a bulk form are introduced into the electronic part mounting apparatus, thereby being able to be mounted on a printed circuit board after being subjected to a predetermined inspection process. Accordingly, the apparatus and method for mounting electronic parts according to the present invention eliminate the need of conventional taping, packing, and tape removal processes, thereby achieving the simplified entire process and a reduction in investment, labor costs, clean room construction costs, and packing material costs, and so on. 
         [0024]    It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings: 
           [0026]      FIG. 1  is a perspective view illustrating an electronic part mounting apparatus according to the present invention; 
           [0027]      FIG. 2  is a detailed perspective view illustrating an electronic part feeder illustrated in  FIG. 1 ; 
           [0028]      FIG. 3  is a detailed sectional view illustrating a first feeder illustrated in  FIG. 2 ; 
           [0029]      FIG. 4  is a sectional view illustrating a defective part discharge unit illustrated in  FIG. 1 ; 
           [0030]      FIGS. 5A to 5C  are views illustrating a polar alignment unit illustrated in  FIG. 1 ; 
           [0031]      FIG. 6  is a perspective view illustrating a part insertion unit illustrated in  FIG. 1 ; 
           [0032]      FIG. 7  is a view illustrating a part supply unit included in the electronic part mounting apparatus according to the present invention; and 
           [0033]      FIG. 8  is a flow chart illustrating an electronic part mounting method according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0034]    Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
         [0035]      FIG. 1  is a perspective view illustrating an electronic part mounting apparatus including a feeder according to the present invention. 
         [0036]    The electronic part mounting apparatus illustrated in  FIG. 1  includes a bulk feeder  110 , a positioning wheel  140 , an inspection unit consisting of a measurement unit  130 , a defective part discharge unit  132 , and a polar alignment unit  134 , an electronic part insertion unit  150 , and a track type part supply unit (represented by reference numeral  180  in  FIG. 7 ). Here, examples of an electronic part  100  include an integrated circuit, diode, condenser, resistor, light emitting diode, and so on, and in the following description, is referred to as a light emitting diode package by way of example. 
         [0037]    The bulk feeder  110 , as illustrated in  FIGS. 2 and 3 , consists of a first feeder  112  into which electronic parts in a bulk form are introduced, and a second feeder  114  connected to the first feeder  112 . 
         [0038]    The first feeder  112  includes a bowl  112   a,  an inner surface of which defines an ascending helical track  116 , and a vibrator  112   b  to support and vibrate the bowl  112   a.    
         [0039]    The vibrator  112   b  is used to vibrate the first feeder  112 , causing the electronic parts  100  received in the bowl  112   a  to ascend to an upper end of the first feeder  112  along the ascending helical track  116 . In this case, the electronic parts  110  are aligned with one another while being moved along the ascending helical track  116 . 
         [0040]    The electronic parts  100  in a bulk form are introduced into the bowl  112   a.  The electronic parts  100  to be introduced into the bowl  112   a  are completely subjected to die bonding, wire bonding, and dispensing processes and also, are classified according to voltage V F , brightness I V , and color coordinate CIE. That is, prior to being introduced into the first feeder  112 , the electronic parts  100  are subjected to die bonding, wire bonding, and dispensing operations and thereafter, are classified according to voltage V F , brightness I V , and color coordinate CIE. 
         [0041]    The bowl  112   a,  as illustrated in  FIGS. 2 and 3 , may include an air blower  124 , the ascending helical track  116 , a sorting sensor  122 , a first feeder controller  106 , and an electronic part full sensor  126 . 
         [0042]    The air blower  124  is used to blow ionized air to the electronic parts  100 , so as to remove static electricity from the charged electronic parts  100 . In addition, the air blower  124 , which functions to provide the electronic parts  100  with air, serves not only to align the electronic parts  100  so as not to overlap one another, but also to realign any incorrectly aligned electronic part  100  having a downwardly facing front surface such that a rear surface of the electronic part  100  faces downward. 
         [0043]    The ascending helical track  116  may take the form of a multi-track suitable to increase a supply quantity of the electronic parts  100 . 
         [0044]    The sorting sensor  122  is used to sense the shape of at least one surface of the front and rear surfaces of the respective electronic parts  100 , thereby sorting defective ones of the electronic parts  100 . More specifically, the sorting sensor  122  is able to detect the quantity of light reflected from an upper surface of each electronic part  100 , determining the electronic part  100  as a defective one if the quantity of light is less than a reference value, or as a good one if the quantity of light is within the range of a reference value. Once the electronic part  100  is determined as a good one, the electronic part  100  is directed to the second feeder  114 . 
         [0045]    The electronic part full sensor  126  is used to sense the presence of the electronic part  100  when the electronic part  100  ascends to an outermost end of the ascending helical track  116  of the first feeder  112 , thus enabling control of an operation starting time of the second feeder  114 . 
         [0046]    In the meantime, the first feeder  112  includes a descending portion (not shown) to allow only the aligned electronic parts  100 , except for the non-aligned electronic parts  100 , to be fed to the sorting sensor  122 . The descending portion takes the form of a stepped portion having grooves between respective vertically arranged turns of the ascending helical track  116 , to allow the non-aligned electronic parts  100 , except for the aligned electronic parts  100 , to descend along the grooves. In this way, the non-aligned electronic parts  100  descend into the bowl  112   a  of the first feeder  112 , to prepare re-feeding thereof. 
         [0047]    In this case, the aligned electronic parts  100  and the non-aligned electronic parts  100  are divided from each other based on at least one of the width and inclination angle of the ascending helical tack  116  and the center of gravity of the electronic parts  100 . For example, if the width of the ascending helical track  116  is set to allow passage of the electronic parts  100  aligned in a given direction while preventing passage of the electronic parts  100  aligned in other directions, the aligned electronic parts  100  are able to pass the descending portion and to be fed to the sorting sensor  122 , whereas the non-aligned electronic parts  100  descend along the descending portion thus being returned into the bowl  112   a  of the first feeder  112 . 
         [0048]    The second feeder  114  is a straight feeder connected to the outermost end of the ascending helical track  116  of the first feeder  112 . The second feeder  114  is controlled by a second feeder controller  108  and serves to feed the electronic parts  100  directed from the first feeder  112  to the positioning wheel  140 . In this case, once the electronic part  100  arrives at an end of the second feeder  114 , an electronic part arrival sensor  128  illustrated in  FIG. 3 , which is located at the end of the second feeder  114 , senses the presence of the electronic parts  100 , enabling control of an operation starting time of the positioning wheel  140 . 
         [0049]    The positioning wheel  140 , as illustrated in  FIG. 1 , includes a basis shaft  144  and a plurality of suction nozzles  142  attached to the basis shaft  144 . 
         [0050]    The basis shaft  144  is installed to enable rotation and vertical movement thereof. 
         [0051]    The plurality of suction nozzles  142  is used to suction and hold the electronic parts  100  respectively, so as to transfer the adhered electronic parts  100  from a previous process to a subsequent process via rotation and vertical movement of the basis shaft  144 . 
         [0052]    The inspection unit may consist of the measurement unit  130 , the defective part discharge unit  132 , and the polar alignment unit  134 . 
         [0053]    The measurement unit  130  is used to determine the presence of defects in the exterior appearance of the electronic parts  100  fed by the plurality of suction nozzles  142 . To this end, the measurement unit  130  may function to form an image of each surface of the electronic parts  100  so as to inspect the exterior appearance of the electronic parts  100  in terms of damage to the electronic parts  100 , exposure of or damage to electrodes, the absence or superabundance of electrodes, length deformation of electrodes, size defects, pin holes, cutting errors, and so on. 
         [0054]    The defective part discharge unit  132 , as illustrated in  FIG. 4 , is used to discharge the electronic parts  100 , determined as defective ones by the measurement unit  130 , into a discharge space  136 , thereby allowing only the electric parts  100 , determined as good ones, to be fed to the polar alignment unit  134 . 
         [0055]    The polar alignment unit  134  realizes polar alignment of the electronic part  100  by using image information acquired by an image forming unit  138  as illustrated in  FIG. 5A , or by applying electric signals to the electronic part  100 . 
         [0056]    Considering the case where the polar alignment of the electronic part  100  is realized via the image forming unit  138 , the polar alignment unit  134 , as illustrated in  FIG. 5A , includes the image forming unit  138 , a controller  196 , and a database  198 . 
         [0057]    The image forming unit  138  forms an image of the electronic part  100  suctioned to the suction nozzle  142 . 
         [0058]    The controller  196  compares the acquired image information with image information stored in the database  198 , thereby calculating a rotated or inverted angle of the electronic part  100 . Referring to  FIG. 5C , a rotation/inversion unit  120  is used to rotate or invert the electronic part  100  according to the calculated rotated or inverted angle of the electronic part  100 , realizing the polar alignment of the electronic part  100 . 
         [0059]    On the other hand, considering the case where the polar alignment of the electronic part  100  is realized via application of electric signals, as illustrated in  FIG. 5B , information related to the polarity of the electronic part  100  is acquired based on electric signals applied to both ends  146   a  and  146   b  of the electronic part  100 . For example, if the electronic part  100  is a light emitting diode, polarity information is acquired according to whether the electronic part  100  emits light or not in response to a forward voltage or invert voltage applied thereto. As illustrated in  FIG. 5C , the electronic part  100  is rotated or inverted by use of the rotation/inversion unit  120  according to the acquired polarity information, resulting in the polar alignment of the electronic part  100 . 
         [0060]    The electronic part insertion unit  150 , as illustrated in  FIG. 6 , includes a carrier tape  154  and a guide rail  152 . 
         [0061]    The carrier tape  154  has recessed pockets  156  successively arranged with a constant interval, such that the electronic parts  100  are able to be inserted into the pockets  156 . 
         [0062]    The guide rail  152  serves to move the carrier tape  154  in which the electronic parts  100  have been received. 
         [0063]    As described above, after the electronic parts  100  are inserted into the pockets  156  of the carrier tape  154 , the electronic parts  100  are transferred to the part supply unit  180  along the guide rail  152 . 
         [0064]    The part supply unit  180 , as illustrated in  FIG. 7 , includes a transfer roll  162 , a pitch transfer device  176 , a grip member  188 , and a display  186 . 
         [0065]    The grip member  188  is provided at one side of a body  160  of the track type part supply unit  180 , to allow a user to grip and move the part supply unit  180 . 
         [0066]    The display  186  is provided at the grip member  188  to visually output an operational state of the part supply unit  180  using characters, etc., to the user at the outside. 
         [0067]    The transfer roll  162  is used to transfer the carrier tape  154 , in which the electronic parts  100  have been received, to the pitch transfer device  176 . Alternatively, the transfer roll  162  may be substituted by a winding roll, around which the carrier tape  154  containing the electronic parts  100  inserted therein is wound. 
         [0068]    The pitch transfer device  176  is used to transfer the carrier tape  154 , in which the electronic parts  100  have been received, to a pickup position of a pickup unit  190  on a per predetermined pitch basis. 
         [0069]    To this end, the pitch transfer device  176  includes a feeding motor  174 , a power transmission gear  170 , a drive wheel  166 , a latch wheel  164 , and a latch stopper  168 . 
         [0070]    The feeding motor  174  is rotated upon receiving drive signals transmitted from a motor drive circuit  182 . 
         [0071]    A drive gear  172  is coaxially coupled to the feeding motor  174  and in turn, the power transmission gear  170  is engaged with the drive gear  172 . Thus, the power transmission gear  170  is rotated upon receiving power generated by the feeding motor  174 . 
         [0072]    The drive wheel  166  and the latch wheel  164  are rotated upon receiving power from the power transmission gear  170 , thereby serving to transfer the carrier tape  154 , in which the electronic parts  100  have been received, to the pickup position of the pickup unit  190  on a per pitch basis. In particular, the drive wheel  166  is provided at an outer circumference thereof with gear tooth such that the gear tooth are inserted into the pockets  156  of the carrier tape  154  to enable transfer of the carrier tape  154 . 
         [0073]    The latch stopper  168  serves to limit a rotation direction of the latch wheel  164 , in order to prevent the drive wheel  166  from rotating in an inversion direction during supply of the electronic parts  100 . 
         [0074]      FIG. 8  is a flow chart illustrating an electronic part mounting method according to the present invention. 
         [0075]    Referring to  FIG. 8 , after a substrate is prepared, electronic parts are die-bonded to a mounting space of the substrate (S 1 ). 
         [0076]    Next, electrodes of the electronic parts are connected respectively to electrode plates of the substrate by wire bonding (S 2 ), and then, the mounting space in which the electronic parts have been mounted is directly molded, or is molded after completion of a dispensing process (S 3 ). 
         [0077]    Next, the electronic parts are classified according to voltage, brightness, color coordinate, and so on (S 4 ). The classified electronic parts in a bulk form are introduced into the bulk feeder (S 5 ). 
         [0078]    Next, after passing through the measurement unit, the defective part discharge unit, the polar alignment unit, and the electronic part insertion unit via operation of the positioning wheel, the electronic parts are picked up from the track type part supply unit and then, are mounted on a printed circuit board (S 6 ). 
         [0079]    As is apparent from the above description, with use of an electronic part mounting apparatus and electronic part mounting method according to the present invention, once electronic part packages are classified according to a predetermined standard, the electronic part packages in a bulk form are introduced into the electronic part mounting apparatus, thereby being able to be mounted on a printed circuit board after being subjected to a predetermined inspection process. 
         [0080]    Accordingly, the apparatus and method for mounting electronic parts according to the present invention have the effect of eliminating the need of conventional taping, packing, and tape removal processes, thereby achieving a simplified overall process and a reduction in investment, labor costs, clean room construction costs, and packing material costs, and so on. More particularly, although a conventional mounting process including taping, packing, and tape removal processes requires costs of about 2.23 billion won, the present invention is capable of reducing mounting costs to about 1.7 billion won owing to elimination of the conventional processes, resulting in cost savings of about 530 million won. 
         [0081]    It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.