Apparatus and method for circuit board routing fixture

An apparatus for retaining and cleaning a circuit board array, which comprise a fixture having a generally elongated connecting surface and one or more terminating open ends, which may optionally integrate a hollow element, creating an aperture in the fixture adjacent to a tab on the circuit board array, wherein the terminating open ends extend toward a machine component having at least one cavity extending through the topside of the machine component, and a vacuum system connected to the cavity, wherein the vacuum system applies suction through the cavity and the terminating open ends.

FIELD OF THE INVENTION

This invention relates to circuit board routing fixtures. More particularly, this invention relates to vacuum systems to remove dust from a circuit board.

BACKGROUND OF THE INVENTION

The manufacture of circuit boards involves the production of a multitude of circuit boards manufactured from a single array, referred to as a circuit board array. The circuit board arrays are manufactured, tooled, and populated with electronic devices, and then cleaved into individual circuit boards so that the individual circuit boards can be assembled into a desired application. The process of removing individual circuit boards from a circuit board array is commonly referred to as de-paneling. One of the methods of de-paneling boards is routing. Circuit board routing is the process by which a number of tabs on a circuit board array are cleaved in order to singulate one circuit board from another circuit board and/or from the excess material (scrap) that may be adjacent to the circuit board. The tabs on the connected circuit board array are routed by a rotating mechanism containing an appropriate bit. The bit is positioned in an opening at the perimeter of the circuit board adjacent to the tab to be routed. The bit moves through the tab and grinds out the tab creating dust and debris, which must be removed.

Circuit board routing uses a fixture to locate and hold the circuit board while the circuit board is being routed. The fixture keeps the circuit board from moving during the routing process. As a circuit board is routed, a vacuum system is used to collect dust created during the routing operation. For dust collection to be effective, the suction created by a vacuum system must be concentrated at the area being routed. A vacuum system creates a space where the pressure is below normal atmospheric pressure, and has a practical result of imposing a suction on that space. A vacuum system applied to a small surface area has a greater suction velocity (pull) then when the same vacuum system is applied to a larger surface area. However, concentrating a vacuum system at the point of the routing operation becomes much more difficult when the circuit board is highly populated with electronic devices, such as integrated circuits, capacitors, resistors and other components.

Current vacuum systems apply suction over a broad surface area of the circuit board array and are unable to sufficiently remove the dust that accumulates in the spaces surrounding where the tabs have been routed. The resulting accumulation of dust can have a detrimental impact on the functionality of the electrical devices housed in the circuit board and/or create environmental concerns due to airborne dust.

As a result, it was desirable to provide an improved vacuum system employed to remove dust from circuit boards.

SUMMARY OF THE INVENTION

The present invention discloses an improved vacuum system. In one embodiment, a fixture is integrated with a vacuum system, which concentrates the vacuum system's suction at the underside of the circuit board directly to areas where the tabs are cleaved. The fixture may further comprise hollow elements, which are localized at each tab on the circuit board array that will be routed. An open end on the bottom of the hollow elements extends into a terminating open end of the fixture, which extends into a cavity underneath the fixture, while the other open end at the other end of the hollow element contacts the surface area surrounding the tab that will be cleaved. The vacuum system applies suction to the cavity and up through the hollow elements.

The vacuum system applies suction pressure to the cavity and hollow elements as the tabs on the circuit board array are routed. The hollow elements are substantially perpendicular to the circuit board array, and as a result, each hollow element is aligned substantially perpendicular under each tab to be routed on the circuit board array. These hollow elements, incorporated into the fixture, apply suction on the underside of the routed tabs. Consequently, each circumference or perimeter, which surrounds the individual tabs to be cleaved, ensures that the dust is effectively removed.

DETAILED DESCRIPTION OF THE INVENTION

While the present invention is susceptible of embodiment in varied forms, what is shown in the drawings will hereinafter be understood to be a preferred embodiment of the present invention. The present disclosure is to be considered as setting forth an exemplification of the invention, which in no way is intended to limit the invention to the specific embodiment illustrated below. In referring to the drawings, like reference numerals and letters indicate like parts throughout the several drawings.

FIG. 1shows an exemplary apparatus for circuit board routing10. In this embodiment, a sixteen CBA20is shown installed on a fixture30, which is a substantially cylindrical element fixture30in this embodiment. However, there are a variety of fixtures30which can be utilized in the present application. The fixture30is installed on a top portion of a fixture adapter40. Fixture30comprises a generally elongated connecting surface31and at least one, and preferably, a plurality of supports32that are connected to and extend transverse from the connecting surface31. In this embodiment, the supports32(hereinafter referred to as “hollow elements”) are substantially cylindrical hollow elements. These hollow elements are positioned substantially perpendicular to the connecting surface31. The hollow elements32are generally elongated with their shape defined by the terminating open end33of the connecting surface31. The terminating open end33is a cut-through creating an aperture in the fixture30. The terminating open end33has a defined circumference or perimeter, which allows vacuum suction to be localized to a particular location on the circuit board. The hollow elements32can take on a number of shapes, including but not limited to, squares or rectangles, all of which extend transverse from the connecting surface31

In one embodiment, the hollow elements32have a first and second open end35, whose openings are defined by the perimeter or circumference of the terminating open end33. In this embodiment, the underside of the CBA20rests across the hollow elements32. In addition, the present embodiment shows, one or more standing pins34, which are substantially cylindrical, connected to, and extending perpendicularly transverse from the connecting surface31. In the present embodiment, a routing machine70, of which any variety known in the art may be used, is utilized to route the CBA20.

In another exemplary embodiment, drilling directly through the fixture30at the tab locations creates the terminating open end, and, no hollow elements32are installed on the fixture. This particular embodiment allows the CBA to rest directly on the fixture30, as vacuum suction is localized directly through the terminating open ends33.

FIG. 2shows generally, an overhead view of an exemplary CBA20, with tabs24positioned throughout the CBA20. The CBA20includes etchings26for six individual circuit boards22, and scrap28between the six circuit boards22. The etchings26carve through the CBA20leaving only the tabs24holding the six circuit boards22to the scrap28.

FIG. 3is an overhead view illustrating, generally, CBA20and fixture30in accordance with an embodiment of the present invention, and open area under each tab24.

FIG. 4is a bottom view of a fixture30.FIG. 4illustrates surface areas D, E, F, and G that are suctioned by a vacuum system50, which is illustrated inFIG. 8in accordance with an embodiment of the present invention. In this embodiment, suction is applied generally to the surface areas D, E, F, and G.

FIG. 5is an overhead view of surface areas a, b and c suctioned by a preferred embodiment of the vacuum system50. A hollow element32or terminating open end33is adjacent to each of surface areas A, B and C. Suction is applied through the hollow element32or terminating open end33to each of areas A, B and C. The circumference or perimeter36of each hollow element32or terminating open end33is preferably sufficient to surround the length of the tabs24ofFIG. 2. The surface areas A, B and C correspond to the tabs24on the printed CBA20shown inFIG. 6.

FIG. 6shows an overhead view of CBA20and tabs24to be cleaved. The etchings26are located in this illustration throughout the outer perimeter of the CBA20, and when the tabs24are cleaved, four circuit boards22are singulated from one another.

FIG. 7is an overhead view illustrating the location of the terminating open ends33on a multiplicity of tabs24. The terminating open ends33have a circumference or perimeter36, which surrounds each of the tabs24to be cleaved. Each individual circumference or perimeter36of each of the terminating open ends33is preferably large enough in size to engulf an individual tab24. Further, the tabs24in this embodiment have varying lengths, and consequently the corresponding terminating open ends33, preferably have different circumferences or perimeters. The suction from the vacuum system50ofFIG. 8is preferably concentrated through one or more of the terminating open ends33, and more preferably, through each one of the terminating open ends33directly to the tabs24, which are cleaved by the routing machine70ofFIG. 1. As can be seen in the figures, the length of the individual tabs24is substantially the same as the diameter across the circumference36of each of the terminating open ends33in this embodiment. This allows for an optimal suction velocity to pass through the individual terminating open ends33, and be directly applied to the area where the routing process is taking place.

FIG. 8is a side planar view illustrating a fixture30, with hollow elements32integrated and channeled through terminating open ends33of the fixture30. Each of the multitude of hollow elements32preferably pass into the terminating open ends33of the fixture30and extend through the aperture created by terminating open ends33, in order to feed into a cavity62, which is illustrated inFIG. 10. In this embodiment the hollow elements32are flush with the bottom of the fixture30, and connected perpendicular to the connecting surface31. Tn some cases, however, the hollow elements may be above or below the bottom of the fixture30. Vacuum system50is shown positioned underneath the fixture30inFIG. 8, and a vacuum hose52extends from the vacuum system and integrates with the fixture30, as will be described in more detail inFIG. 10.FIG. 8also illustrates the first open end33of the hollow element32.

FIG. 9shows another overhead view of CBA20, having the same CBA20as inFIGS. 2 and 3, positioned on fixture30. The figure shows six separate circuit boards22, which are singulated by the routing process, and the resulting scrap28is preferably disposed.FIG. 9further illustrates the circumference or perimeter36of the hollow elements32or terminating open ends33in relation to the length of the tabs24. The diameter or length of the open ends of the hollow elements32or terminating open ends33are preferably substantially similar to the length of the tabs24. Each terminating open end33, or hollow element32is still large enough to surround the tabs24. Further, the first open end35ofFIG. 8is large enough to surround the tabs24.

FIG. 10shows an exemplary fixture adapter40installed on machine top plate60. The machine top plate60has the cavity62. The cavity62has vacuum hose52connected on the underside of the machine top plate60, and applies suction through the cavity62, and then up through the terminating open ends33, and then through the hollow elements32. The vacuum system50applies suction to the underside of the fixture30when the fixture30is installed on fixture adapter40.

FIG. 11shows a preferred embodiment of the fixture30installed on the top surface of the fixture adapter40. In this embodiment, thirty-two hollow elements32, and four standing pins34flanking the outside rows of the hollow elements32are provided, although as should be understood, other numbers of elements32and standing pins34can also be provided where desired. The standing pins34provide support when a CBA20is placed on top of the hollow elements32. In operation, when the vacuum system50is utilized, it applies suction through the terminating open ends33and up through hollow elements32and down into the cavity62, as illustrated inFIG. 10. Also, this embodiment shows the first open end35, of the hollow element32, through which suction is applied.

The components illustrated in the exemplary embodiments can be comprised of a number of suitable materials. The fixture plate, fixture adapter, and machine top plate can be comprised of, individually or in combination, steel, aluminum, titanium alloy, or any other of a number of materials, which exhibit the aforementioned materials characteristics. In a preferred embodiment tile fixture plate is comprised of aluminum. The hollow elements can be comprised of any of a number of materials including steel, aluminum, and those exhibiting plastic qualities, such as polyethylene, and also material such as TEFLON®, DELRLN® or nylon. The CBA described in the exemplary embodiments of this invention is comprised of materials well understood and recognized in the art.

The above description and the views and materials depicted by the figures are for purposes of illustration only and are not intended to be, and should not be construed as, limitations on the invention.

Moreover, certain modifications or alternatives may suggest themselves to those skilled in the art upon reading of this specification, all of which are intended to be within the spirit and scope of the present invention as defined in the attached claims.