Abstract:
An apparatus for segregating electronic components that engages and stops each of a plurality of electronic packages passing down a singulation tube is disclosed. In addition, the segregating apparatus is cable of segregating the electronic packages even though some of them had been linked together during the sealing process. The segregating apparatus includes a first swing arm to clip a electronic component, a second swing arm to clip another electronic component, and a third swing arm to depart the two electronic components, where all of components of the segregating apparatus are driven by a single driving force, reducing the size of the apparatus and the time needed for the segregating process.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to semiconductor device segregating apparatus, and more specifically, to semiconductor device segregating apparatus capable of segregating a large number of semiconductor devices in a fast and efficient manner. 
     2. Description of the Prior Art 
     After the packaging process, singulation machines are commonly equipped with an off-loading apparatus for loading electronic packages into a tube, then the tube is transported to the inspection station for detecting the damaged electronic packages in order to assure quality. 
     As shown in  FIG. 1 , a tube  102  is mounted at an inclined angle so that electronic packages that have been fed into the tube  102  can slide under gravity one by one into a receptacle  112  installed in the lower end. The receptacle  112  is employed for storing the electronic packages after an inspection process is completed in an inspection zone  110 . The electronic packages slide through a feed zone  104 , then a separating device  108  including two pneumatic pistons  108   a  and  108   b  engages and stops each of the electronic packages. The area where the electronic packages are stopped is referred to as the holding zone  106 . A plurality of electronic packages  103  (hereinafter referred to as DUT) is held in this area prior to entering the inspection zone  110 . 
     After being horizontally inserted into the feed zone  104 , the left end of the tube  102  is elevated in order to facilitate movement (e.g. sliding down) of the DUTs  103  under the pull of gravity. As shown in  FIG. 2A , the DUT  103   a  nearest to the inspection zone  110  is engaged in the holding zone  106  by a stop  108   a  (hereinafter referred to as the first pneumatic piston), and consequently a sequence of DUTs is stopped in the holding zone  106 . Then DUT  103   b  that is near DUT  103   a  is engaged by the other pneumatic piston  108   b  (hereinafter referred to as the second pneumatic piston), as shown in  FIG. 2B . Finally, the first pneumatic piston  108   a  is drawn back resulting in the DUT  103   a  sliding to the inspection zone  110  under gravity. Similarly, other DUTs stopped in the holding zone  106  can slide to the inspection zone  110  one by one through repetition of the steps mentioned hereinbefore. 
     A number of improvements can be made to the separating device  108  shown in  FIG. 1 . For example, because excess sealing material  101  (shown in  FIG. 3 ) causes the DUTs  103  to link together during the sealing process, they cannot be separated by the separating device  108 , thereby jamming the holding zone  106 ; hence the equipment must be shut down to remove the linked DUTs, and time is wasted. In addition to the time of troubleshooting, multiple pneumatic pistons  108  require significant capital investment, a large working space, and especially extra time for separation of the DUTs  103 . Accordingly, if the troubleshooting process can be eliminated, and if the working space and separating time can be reduced, costs associated with separating electronic packages can be decreased significantly. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing, it is an object of the present invention to provide an apparatus that engages and stops each of a plurality of electronic packages passing down a tube. The apparatus includes a single driving force (e.g. driver) for driving one pneumatic piston thus reducing space of the apparatus and time of the process. 
     It is another object of the present invention to provide a segregating apparatus cable of segregating the electronic packages, some of which potentially had been linked together, thus eliminating the troubleshooting process and increasing the yield. 
     According to the objects, the present invention provides a segregating apparatus that includes a single driving force (e.g. driver) for driving a pedestal down, the pedestal being structured to drive three swing arms including a first swing arm, a second swing arm, and a third swing arm beneath it. The first swing arm is employed for driving a first finger set, which is capable of clipping a first DUT; the second swing arm is employed for driving a second finger set, which is capable of clipping a second DUT; and the third swing arm is employed for driving a first block and thus a second block to control a stop arm. In addition, the first block pushes the first finger forward to release the DUT that has been clipped by the first finger. The whole segregating process for separating the first DUT and the second DUT can be completed as follows: clipping the first DUT by the first finger; clipping the second DUT by the second finger; moving the first finger forward thus segregating the first DUT and the second DUT; releasing the first DUT and rising the stop arm for passage of the first DUT down and out of the segregating apparatus. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an overall system diagram of a prior-art machine. 
         FIGS. 2A-2C  illustrate diagrams of the first/second DUT being stopped or not stopped by the first/second pneumatic piston of a prior-art machine. 
         FIG. 3  provides a diagram of DUTs being linked together during the sealing process. 
         FIG. 4A  is a front view of one embodiment including a segregating apparatus in accordance with the present invention. 
         FIG. 4B  is an enlarged side view of the segregating apparatus shown in  4 A. 
         FIG. 4C  is a section view of the structure depicted in  FIG. 4B . 
         FIG. 4D  is an enlarged side view of a second finger set of the present invention. 
         FIG. 5  is a flow chart describing segregating steps in accordance with the present invention. 
         FIGS. 6A and 6B  diagram clipping by a first controlling mechanism, driven by a first swing arm, of a first DUT according to the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A detailed description of the present invention will now be disclosed with reference to the following embodiments, which are not intended to limit the scope of the present invention, and which can be adapted for other applications. While the drawings are illustrated in detail, it is appreciated that the quantity of the disclosed components may be greater or less than that disclosed, except where the amount of components is expressly restricted. 
       FIGS. 4A-4D  illustrate an embodiment according to the present invention.  FIG. 4A  is a front view of the embodiment. A segregating apparatus  10  for engaging and stopping each of a plurality of DUTs (e.g. electronic packages) passing down a tube includes a driving force (e.g. driver)  12  such as a pneumatic piston whose lower end connects to a pedestal  14 , which comprises an upper support  14   a , a first spring  14   b , a second spring  14   c , a first press  14   d , and a second press  14   e . The first press  14   d  and the second press  14   e  are coupled to the upper support  14   a  by the first spring  14   b  and the second spring  14   c , respectively. 
       FIG. 4B  is an enlarged side view of the segregating apparatus  10  shown in  FIG. 4A , and  FIG. 4C  is a part section view of  FIG. 4B , wherein the view is presented in two dashed rectangles. Both a first swing arm  16  and a third swing arm  20  are mounted under the first press  14   d  and are coupled to a first finger set  22  and a first block  28 , respectively, wherein the first finger set includes a first controlling mechanism  22   a  and a first finger  22   b , and the first controlling mechanism has the shape of an inverted U, V, or the like. The first swing arm  16  is capable of controlling the first finger  22   b  via the first controlling mechanism  22   a . The third swing arm  20  is employed for pushing the first block  28  mounted behind the first swing arm  16 , and the first block  28  is used for pushing the first finger  22   b  and a second block  30  via a third spring  29   a  and a bolt  29   b , respectively, as shown in  FIG. 4C . When the first finger  22   b  is pushed to a predetermined position, it will depart from the first controlling mechanism  22   a  and spread, thus releasing the DUT that has been clipped. Similarly, when the second block  30  is pushed to a predetermined position, a stop arm  26  mounted on the second block  30  will depart from a hook  27  and cause the stop arm  26  to rise. The stop arm  26  is installed between the segregating apparatus  10  and an inspection zone (not shown). The DUTs slide down to the inspection zone while the stop arm  26  is risen up, and are stopped in the segregating apparatus  10  while the stop arm  26  is hooked in the hook  27 . 
       FIG. 4D  is an enlarged side view of  10   b  shown in  4 A. Similar to the first swing arm  16 , a second swing arm  18  located under the second press  14   e  is coupled to a second finger set  24 , which comprises a second controlling mechanism  24   a  and a second finger  24   b , wherein the second controlling mechanism has the shape of an inverted U, V, or the like. 
     The segregating process according to the present invention is carried out with a sequence of steps. As mentioned hereinbefore, the driver  12  supplies the driving force to lower the first press  14   d  and the second press  14   e  at the same time by pressing the upper support  14   a  connected to the first spring  14   b  and the second spring  14   c . Thus, the first press  14   d  presses the first swing arm  16  and the third swing arm  20  under it, and the second press  14   e  presses the second swing arm under it. The first swing arm  16 , the second swing arm  18 , and the third swing arm are originally at the same elevation. In order to accomplish pressing of the first swing arm  16  first, pressing of the second swing arm  18  second, and pressing of the third swing arm  20  third, the distance (gap) between the first press  14   d  and the first swing arm  16  is made shorter than the distance between the second press  14   e  and the second swing arm  18 , and the distance between the second press  14   e  and the second swing arm  18  is made shorter than the distance between the first press  14   d  and the third swing arm  20 . For example, this can be achieved by a first bump  15  being added between the first press  14   d  and the first swing arm  16  and a second bump  17  being added between the second press  14   e  and the second swing arm  18 , wherein the first bump  15  has a volume larger than the volume of the second bump  17 . Consequently the first swing arm  16  will be pressed first, the second swing arm  18  be pressed second, and the third. swing arm  20  be pressed third. 
     The segregating process of one embodiment according to the present invention will be described in detail as follows with reference to  FIG. 5 :
         (i) the driver  12  is actuated for dropping and pressing the upper support  14   a , hence the upper support  14   a  will press the first press  14   d  via the first spring  14   b  and press the second press  14   e  via the second spring  14   c.      (ii) the first press  14   d  presses the first swing arm  16  first, so that a first DUT  13  (see  FIG. 6B ) will be clipped by the first finger  22   b , which is driven by the first controlling mechanism  22   a , which is driven by the first swing arm  16 .   (iii) as the upper support  14  is still dropping, and similar to the first swing arm  16 , the second press  14   e  presses the second swing arm  18 , so that a second DUT (not shown) will be clipped by the second finger  24   b , which is driven by the second controlling mechanism  24   a , which is driven by the second swing arm  18 .   (iv) as the upper support  14  is still dropping and thus pressing the third swing arm  20 , the first block  28  is pushed forward to press the third spring  29   a  and the bolt  29   b  (see  FIG. 4C ), hence the first finger  22   b  is pushed forward via the bolt  29   b ; consequently the first DUT clipped by the first finger  22   b  and the second DUT which clipped by the second finger  24   b  will be separated while the first finger  22   b  is moving forward.   (v) the first finger  22   b  is moved forward and departed off the first controlling mechanism  22   a , and thus the first finger  22   b  spreads and releases the first DUT.   (vi) in the meanwhile, the second block  30  is pushed forward to a predetermined position via the bolt  29   b , the stop arm  26  mounted on the second block  30  will be departed from the hook  27  and be risen up, therefore the first DUT, released by the first finger, will slide down to the inspection zone, but the second DUT remains clipped by the second finger  24   b.      (vii) the driver  12  is retracted; hence the first spring  14   b , the second spring  14   c , and the third spring  29   a  will be retracted due to the spring force and thus the components which coupled to the springs will be drawn back to original position, the second finger  24   b  will release the second DUT and the hook  27  will hook the stop arm  26  again, and the second DUT slides down and replaces the position of the first DUT but is stopped by the stop arm  26 .       

     By repeating the steps as described above, the segregating process is continued. 
     According to the present invention, the segregating apparatus  10  for separating the DUTs is driven by only one driving force (e.g. driver); therefore the working space is reduced. In addition, the segregating process is capable of segregating continuously without switching to other drivers, and thus the process is simplified and accelerated. Moreover, because the DUTs can be separated by the finger  22   b / 24   b  even though they are linked together during the sealing process, the major cause of abnormal shut down is eliminated, and therefore the yield is increased. 
     While the invention has been described in conjunction with a specific mode, a number of variations may be made according to the present invention. For example, the controlling mechanism  22   a / 24   a  with the shape of a U, V, or the like is also practicable in other embodiments. Arranging the swing arms  16 / 18 / 20  in order of height is a possible alternative to replace the bumps  15 / 17 . Moreover, it will be possible in other embodiments if the sequence being pressed is the second swing arm  18 , the first swing arm  16 , and the third swing arm  20 , because the first DUT is still to be released first. Therefore, it will be appreciated by those skilled in the art that various modifications, alternatives and variations may be made without departing from the scope of the present invention, which is intended to be limited solely by the appended claims.