Abstract:
An automatic feeding and crimping device of an applicator in a terminal making machine for flexible printed circuits, flat cables and cable terminals allows easy adjustment of a feed number of terminals and serves to automatically feed the terminals for the applicator to crimp the terminals with a flexible printed circuit, a flat cable or other cable terminals, thereby providing industrial benefits related to fast and precise terminal processing and flexible feed pitches.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention relates to an innovate design of a feeding system of an applicator in a terminal making machine, which serves to automatically feed flexible printed circuits, flexible flat cables and so on for crimping terminals thereon. 
         [0003]    2. Description of Related Art 
         [0004]    A terminal crimping machine is known to combine metal terminals with stranded wire or a copper cord covered by the metal terminals in a mold so as to establish electric connection between electrode ends or signal ends of the terminals and the wire or cord. 
         [0005]    Presently, flexible printed circuits and flexible flat cables have been widely used in electrical machinery, electronic and computer-related fields for electrodes or signal transmission. The so-called flexible printed circuit (also known as FPC) is made by coating copper foil on a flexible polyimide (PI) or polyethylene terephthalate (PET) substrate, and etching the copper foil to create a single-sided, double-sided or multilayer circuit that is flexible, on which circuit electronic devices or press buttons may be added. Such a light and compact flexible printed circuit can be implanted into various electric and electronic apparatuses in a space-saving manner. On the other hand, the so-called flexible flat cable (also known as FFC) is made by combining an insulating material such as PET and a very thin flat tinned copper wire in a high-tech automated wire making machine into a flexible flat cable that acts as a transmission medium for electricity or signals in various electric and electronic apparatuses. 
         [0006]    Both flexible printed circuits and flexible flat cables enjoy the advantages of softness, capacity for being bent and folded, small thickness, compactness, easy connection and disconnection, and usefulness for addressing electromagnetic interference (EMI). Therein, flexible printed circuits are suitable applications where special requirements are made to compactness or curved profiles, and may be equipped with electronic devices such as connectors, resistors, capacitors, light-emitting diodes and touch switches, in addition to circuit layouts, so as to act as electronic components with specific functions but not only connecting members. By comparison, flexible flat cables are more economical than flexible printed circuits under cost considerations, and thus are extensively used for electric connection or signal connection between various circuit boards. 
         [0007]    For connecting with other connecting members, such a flexible printed circuit/flexible flat cable B must have its copper-foil/copper-wire connecting end B 1  be crimped together with terminals A 1 , and have plural terminals such processed inserted into a plastic housing to form a finalized FPC/FFC assembly. 
         [0008]    As shown in  FIG. 1  and  FIG. 3 , in the course of fabricating the terminals, for facilitating its assembling to a copper-foil/copper-wire connecting end B 1  of a flexible printed circuit, a flexible flat cable, a normal flat cable or a wire B through crimping, a continuous terminal band A is made of a metal sheet by means of a precise in-mold punching process. The continuous terminal band A has a plurality of equidistant terminals A 1 , pitch-setting hole A 2  and band-positioning portions A 3 . Each said terminal A 1  has one end formed with piercing legs A 11  and an opposite end formed with a square-headed contacting section A 12  or a U-headed contacting section A 13  for connecting a male terminal. At a reverse side of the piercing legs A 11  and the square-headed contacting section A 12  or the U-headed contacting section A 13 , there is a clip A 14  for engaging with a plastic housing of the resultant terminal connector. However, it is difficult to ensure the precise combination between the copper-foil/copper-wire connecting end B 1  of the flexible printed circuit/flexible flat cable B and the terminals A 1  through the crimping process. Currently, specialized terminal crimping machines are used for the crimping process to crimp one terminal one time. 
         [0009]    The foregoing terminal A 1  may have its contact region formed into the contact specifications of either the square-headed contacting section A 12  or the U-headed contacting section A 13 . Therein, the square-headed contacting section A 12  requires relatively large band length for forming the square frame of the contact region. In this case, for punching the continuous terminal band A, the adjacent terminals A 1  are spaced by a distance D 1  of 5.08 mm. On the other hand, the U-headed contacting section A 13  only requires relatively small band length for forming the semicircle or U-shaped frame of the contact region. In this case, for punching the continuous terminal band A, the adjacent terminals A 1  are spaced by a distance D 2  of 2.54 mm. However, in practice, on the connecting end B 1 , an interval between two adjacent said terminals A 1  is set as 2.54 mm. 
         [0010]    Thus, clearly, when the continuous terminal band A having U-headed contacting sections A 13  is to be combined with the flexible printed circuit/flexible flat cable B with the set intervals of 2.54 mm, plural abreast terminals A 1  can be processed at one time. However, when the continuous terminal band A with square-headed contacting sections A 12  is to be combined with the flexible printed circuit/flexible flat cable B, it is impossible to crimp plural abreast terminals A 1  at the same time. For instance, to make a 13-pin assembly, the conventional crimping method is to feed the terminals with a feed pitch of 5.08 mm and otherwise feed the flexible printed circuit/flexible flat cable B with a different feed pitch of 2.54 mm. By setting the terminal making machine for a 13-pin crimping process and activating it, the terminal making machine will crimp one pin a time until the total 13 pins are finished. In such a case, the biggest concerns are the feeding accumulated error evolving through the 13-pin crimping process and high material loss (and in turn the low yield) due to jams and/or deviation of the terminals or the flexible printed circuit/flexible flat cable B. In addition, the operation is complicated and preciseness is difficult to secure. Moreover, various jigs and crimping molds are involved in the crimping process. Thus, even for crimping terminals of the same specification, several procedures with use of different jigs/molds have to be done, and consequently incur high processing costs, unstable product quality as well as very high defective rate. 
         [0011]    In view of the above shortcomings, the inventor of the present invention has invented the disclosed device, which allows continuous terminal bands A with both square-headed contacting sections A 12  and U-headed contacting sections A 13  to be automatically fed and later crimped with flexible printed circuits/flexible flat cables. 
       SUMMARY OF THE INVENTION 
       [0012]    The inventor of the present invention, basing on his decades of experience in terminal crimping, molding, and manufacturing, conducted long-term researches, and eventually developed an “automatic feeding and crimping device of an applicator in a terminal making machine for flexible printed circuits, flat cables and cable terminals.” Therein, to perform a crimping process for continuous terminal bands A with square-headed contacting sections A 12 , two said continuous terminal band A and A′ with terminals A spaced by 5.08 mm are offset stacked and placed in a feeding channel, so as to make two adjacent terminals A 1  on respective said bands A and A′ spaced by 2.54 mm, equal to the default distance of a copper-foil/copper-wire connecting end B 1  of a flexible printed circuit/flexible flat cable B (for an application of 1.27 mm, terminal bands with terminals spaced by 2.54 mm are stacked offset in the same manner), and thus the abreast terminals A 1  in a number between two and forty can be perfectly crimped with the copper-foil/copper-wire connecting end B 1  in a single step, thereby providing advantageous of fast process, low defective rate and zero accumulated feeding error. To perform a crimping process for a continuous terminal band A with U-headed contacting sections A 13  spaced by the default distance of the copper-foil/copper-wire connecting end B 1 , i.e. 2.54 mm, the continuous terminal band A is placed into the feeding channel, and the abreast terminals A 1  in a number as desired, between two and forty, can be crimped with the copper-foil/copper-wire connecting end B 1  in a single step of the flexible printed circuit/flexible flat cable B. To make products with terminals spaced by 1.27 mm, terminal bands with terminal spaced by 2.54 mm may be offset stacked the abreast terminals A 1  in a number as desired, between two and forty, can be crimped with the copper-foil/copper-wire connecting end B 1  in a single step of the flexible printed circuit/flexible flat cable B, so that perfect connection can be achieved in a fast, neat, low-loss and error-free manner. 
         [0013]    The disclosed device includes a plurality of feeding pitch holes. For proceeding different numbers of the terminals A 1  on a continuous terminal band A, by merely putting a feed setting post into the proper feeding pitch hole, a feeding slider is directed to automatically deliver the terminals A 1  of the set number batch by batch. In addition, a plurality of spacing pins on a mold in the applicator serve to position well pitch-setting holes A 2  on the continuous terminal band A before the mold is closed, so as to ensure a precise crimping process. At the end of the crimping process, a cutting means of the device serves to equidistantly cut scrap. 
         [0014]    The disclosed device further has a band retaining hook, so that the terminals A 1  of the set number being fed forward can be prevent from going back or bias. Moreover, the disclosed device is ended by a scrap chopper, which serves to chop scrap equidistantly into small pieces, for facilitating disposal and collection of the scrap. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    The invention as well as a preferred mode of use, further objectives and advantages thereof will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein: 
           [0016]      FIG. 1  shows continuous terminal bands with square-headed contacting sections spaced by 5.08 mm; 
           [0017]      FIG. 2  is a perspective view of a finalized flexible printed circuit/flexible flat cable with the square-headed contacting sections according to the present invention; 
           [0018]      FIG. 3  shows a continuous terminal band with U-headed contacting sections spaced by 2.54 mm; 
           [0019]      FIG. 4  is a perspective view of a finalized flexible printed circuit/flexible flat cable with the U-headed contacting sections according to the present invention; 
           [0020]      FIG. 5  is an applied view of the present invention installed on a terminal making machine; 
           [0021]      FIG. 6  is a schematic view of the device of the present invention; 
           [0022]      FIG. 7  is a partial, enlarged perspective view of the device of the present invention; 
           [0023]      FIG. 8  is a side view of the device of the present invention; and 
           [0024]      FIG. 9  is a partially enlarged schematic view of the device of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]    Referring to  FIG. 5  through  FIG. 8 , the present invention provides an automatic feeding and crimping device equipped at a lower portion of a conventional terminal making machine P. The disclosed device has a base  1 , a vertical sliding guide  11  fixed on a side of the base  1 , a slider  12  settled in the vertical sliding guide  11  to be vertically movable and connected to a main shaft of the terminal making machine P, an upper crimping mold part  121  and upper cutter  122  fixed to a bottom of the slider  12 , wherein the upper crimping mold part  121  has a downward surface provided with a plurality of spacing pins  1211 , a lower mold part  123  deposited on the base  1  upward corresponding to the upper crimping mold part  121 , wherein the lower mold part  123  has an upward face provided with a plurality of bend-guiding recesses  1231  for guiding piercing legs A 11  to bend, and a cutter receiving surface  1221  deposited on the base  1  upward corresponding to the cutter  122 . 
         [0026]    As shown in  FIG. 7 , the slider  12  has one side fixed with a downward pusher  124 . Below the downward pusher  124 , there is a scrap chopper  1241  deposited on the base  1 . The scrap chopper  1241  has a severing knife  1242  formed on waist a through hole  1243  that allows a scrap C to pass therethrough. Whenever the downward pusher  124  moves downward with the slider  12 , it drives the severing knife  1242  to move downward and thereby sever the scrap equidistantly. 
         [0027]    A guiding board  13  is attached to the base  1  beside the lower mold part  123  for allowing a flexible printed circuit/flexible flat cable B to be placed thereon. The guiding board  13  is equipped with an adjustable positioning aid  131 . Near an opposite end of the base  1 , a transverse plate  14  is formed on waist a feeding tunnel  141 , which allows a continuous terminal band A to be inserted from one end thereof toward the upper crimping mold part  121 . A rail  142  is mounted atop the transverse plate  14  and bilaterally formed with equidistant feeding pitch holes  143 . Each of the feeding pitch holes  143  allows a feed setting post  144  to be inserted according to a desired number of terminals A 1  to be fed. The rail  142  receives a feeding slider  145  sliding therein. The feeding slider  145  is connected to a shaft  1461  of a cylinder  146  fixedly deposited on the rail  142  through a driven rod  1451 . Below the feeding slider  145 , a positioning claw  1452  is settled in the feeding tunnel  141 , and a spring coil  1453  is mounted on the positioning claw  1452 . In its each backward travel, the feeding slider  145  touches and gets stopped by the feed setting post  144 . 
         [0028]    On an opposite end of the rail  142 , there is a terminal-band crimping screw  1454 , which comprises a spring  1455  and a crimping nut  1456 , so that the tension of the fed continuous terminal band A can be manually adjusted, there by achieving precise positioning and preventing the terminals from going backward. 
         [0029]    As shown in  FIG. 9 , an anti-reverse seat  147  is mounted on the transverse plate  14  in front of the feeding slider  145 . The anti-reverse seat  147  has its lower part equipped with a band retaining hook  149  that is set in the feeding tunnel  141  and controlled by a spring  148 . The band retaining hook  149  serves to limit the terminals A 1  to going forward and retain them from going backward. The anti-reverse seat  147  further comprises an adjusting bolt  1471  passing therethrough for fine adjustment of the forward movement of the feeding slider  145 . 
         [0030]    To specify, as known, in the crimping process, if full automatic feeding is adopted, it is likely that further terminals are fed before the crimped workpiece is removed, causing both the terminals and the workpiece to be damaged. Thus, manually-controlled feeding operated by a press button is preferred. In this case, after the workpiece is crimped, the subsequent terminals will not be fed until the workpiece is removed from the line and the press button is pressed, thereby minimizing loss. A feeding switch  15  is provided at a frontage of the base  1  and is electrically connected to a control circuit of the terminal making machine P. By pressing the feeding switch  15 , the cylinder  146  is driven to slide backward to the feed setting post  144 , and then slide forward to bring the terminals A 1  of the set number forward. 
         [0031]    Referring to  FIG. 6 , the terminal making machine P associated with the disclosed device is electrically connected to a pedal switch W. By stepping down the pedal switch W, the main shaft of the terminal making machine P pushes the slider  12  downward to a predetermined position for crimping the terminals A and the copper-foil/copper-wire connecting end B 1  of the flexible printed circuit/flexible flat cable B, and then the slider  12  return upward to its standby position. 
         [0032]    In use of the device, two continuous terminal bands A and A′ that each have terminals A 1  spaced by 5.08 mm and are offset stacked with each other are or a continuous terminal band A with terminals A 1  spaced by 2.54 mm is placed into the feeding tunnel  141  of the transverse plate  14  so as to pass through the feeding slider  145 , the anti-reverse seat  147  and the lower mold part  123 . The scrap thereof then passes through the scrap severing unit  1241 . 
         [0033]    For performing the crimping process, the number of the terminals A 1  to be combined with the flexible printed circuit/flexible flat cable B is first set, and the feed setting post  144  is inserted into the corresponding feeding pitch hole  143 , such as the 13 th  hole for a 13-pins flexible printed circuit/flexible flat cable. Afterward, by pressing the feeding switch  15 , the control circuit makes compressed air enter an air-inlet tube  146 A of the cylinder  146 , so the feeding slider  145  inside the rail  142  of the transverse plate  14  is then driven to move backward and stop by the feed setting post  144 . Following, the control circuit makes compressed air enter another air-inlet tube  146 B of the cylinder  146 , so the feeding slider  145  inside the rail  142  of the transverse plate  14  is driven to move forward while the positioning claw  1452  below the feeding slider  145  brings terminals A 1  of the set number to moving forward and stopping on the lower mold part  123 . At this time, the flexible printed circuit/flexible flat cable B is placed on the positioning aid  131  of the guiding board  13  so as to align with a front edge of the cutter  122 . 
         [0034]    Then, by stepping down the pedal switch W, the main shaft of the terminal making machine P pushes the slider  12  downward, and in turn pushes the upper crimping mold part  121  and the upper cutter  122  downward. Meantime, the spacing pins  1211  on the downward surface of the upper crimping mold part  121  pass through the pitch-setting holes A 2  of the continuous terminal band(s) A (A, A′) to well position the band(s) A (A, A′) for crimping. Then, when the upper crimping mold part  121  and the upper cutter  122  move downward, the make piercing legs A 11  of the terminal A 1  precisely pierce through the copper-foil/copper-wire connecting end B 1  of the flexible printed circuit/flexible flat cable B, and get bent in virtue of the bend-guiding recesses  1231  of the lower mold part  123  to grasp and electrically contact the copper-foil/copper-wire connecting end B 1  of the flexible printed circuit/flexible flat cable B, as shown in  FIG. 2  and  FIG. 4 . 
         [0035]    The upper cutter  122  cooperates with the cutter receiving surface  1221  to cut the terminal A 1  at a front edge of the square-headed contacting section A 12  or U-headed contacting section A 13 , so as to disconnect the batch(es) of terminals A 1  from the continuous terminal band A (A, A′) and the scrap C. At the same time, the downward pusher  124  moves downward to push down the severing knife  1242  of the scrap severing unit  1241 , thereby equidistantly chopping the scrap C passing the scrap severing unit  1241  into small pieces, for facilitating disposal and collection of the scrap. 
         [0036]    After pushing the slider  12  to complete the above operation, the main shaft of the terminal making machine P moves upward to lift the slider  12  and return it to its standby position. Thereby, automatic, precise feeding of the terminals A 1  and the one-step crimping process can be accomplished. 
         [0037]    The bend-guiding recesses  1231  formed on the upward surface of the lower mold part  123  may be alternatively formed on the downward surface of the upper crimping mold part  121 , so as to allow the continuous terminal band(s) A (A, A′) to be fed reversely and receive the crimping process.