Patent Abstract:
A method of forming a circuit board with electronic assemblies lying in different planes, includes providing a single circuit board with entire electronic assemblies pressed thereon. A channel is then formed in the circuit board of a predetermined depth to divide the circuit board into two separate, but integral portions. The circuit board is then bent at a point between the first and second portions of the circuit board such that the second portion of the circuit board can be bent between 0 and 180 degrees with respect to the first portion of the circuit board.

Full Description:
This is a division of application Ser. No. 09/016,782 filed on Jan. 30, 1998 now U.S. Pat. No. 5.903,440. 
    
    
     TECHNICAL FIELD 
     The present invention relates to the formation of electronic assemblies consisting of multiple circuit boards lying in different planes. More specifically, the present invention relates to a method of bending portions of a single circuit board so that integral portions of a single circuit board lie in different planes. 
     BACKGROUND ART 
     Currently, multiple circuit boards are employed during the assembly of various electronic assemblies. Some electronic assemblies utilize multiple circuit boards lying in different planes because it is not possible to house the components on a single circuit board. One example of such an assembly includes a horizontal main circuit board with a separate vertical display/control circuit board for switches and displays such as used in car audio products. Another example of such an assembly includes a horizontal main circuit board with a separate vertical circuit board for housing components attached to a vertical heat sink. Still another example of such an assembly includes a horizontal main circuit board with a separate vertical circuit board for mounting connectors. Many other applications exist that require the use of multiple circuit boards lying in different planes. 
     In the assemblies that require separate circuit boards lying in different planes, the various boards must be placed in electrical communication in some way. Typically, the horizontal circuit boards and the vertical circuit boards are connected by cables, soldered wires, plugs or other connectors extending between the two boards. The connections between the multiple circuit boards can require the use of many separate wires or connectors. These assemblies are costly and time consuming. Additionally, because of the separate individual connections required at each of the multiple circuit boards, these assemblies are more failure prone than a single circuit board. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to overcoming one or more of the problems as set forth above. It is an object of the present invention to provide a circuit board assembly with portions lying in different planes that eliminates the need for separate wires, plugs, or other connectors. 
     A further object of the present invention is to provide a circuit board assembly that is less expensive and less time consuming to manufacture. 
     Another object of the present invention is to provide a method of forming a circuit board assembly with a single circuit board with integral portions lying in different planes that is less failure prone than prior assemblies. 
     According to the present invention, the foregoing and other objects are attained by providing a circuit board assembly, including a single circuit board. 
     The single circuit board has an entire component assembly built thereon. The circuit board has two separate portions, a first portion of which lies in a predetermined plane and the second portion of which is integral with the first portion and lies in a separate plane from said first portion. The angle between the first portion and the second portion can be anywhere from above 0 to less than 180 degrees. A channel is formed in the circuit board between the first portion of the circuit board and the second portion of the circuit board to assist in the bending of the circuit board. 
     It is an additional object of the present invention to provide a method of forming a circuit board with electronic assemblies lying in different planes for use in vehicle audio products. An entire assembly is built on a single circuit board such that the circuit board has a first portion and a second portion. The circuit board is then heated locally to soften the circuit board at a location between the first portion and the second portion. The circuit board is then bent at the location between the first portion and the second portion such that the second portion of the circuit board is displaced from between 0 and 180 degrees with respect to the first portion of the circuit board. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a circuit board assembly with a channel formed therein prior to forming in accordance with a preferred embodiment of the present invention; 
     FIG. 2 is a perspective view of the circuit board assembly of FIG. 1 after forming in accordance with a preferred embodiment of the present invention; 
     FIG. 3 is a perspective view of a circuit board assembly prior to forming in accordance with another preferred embodiment of the present invention; and 
     FIG. 4 is a perspective view of the circuit board assembly of FIG. 3 after forming in accordance with another preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 illustrates a circuit board  10 . The circuit board  10  has an entire component assembly formed in on one or both of its top surface  12  and its bottom surface  14 . The components that comprise the assembly would be well known to those of ordinary skill in art depending upon the application for which the circuit board  10  is being used. However, a plurality of conducting traces  16  are shown formed on the top surface  12  of the circuit board  10 . It should be understood that there are many different types of component assemblies that may be utilized. For example, a single-side circuit board with traces on one side only may be used. Additionally, a two-sided circuit board with traces on both sides and through-board connections by holes that are plated through or printed through with conductive material may be utilized. Still further, a multi-layer board with traces on both sides of the board as well as on the layers within the board. 
     The circuit board  10  shown in FIG. 1 is a circuit board formed by a plated through hole process and has a channel  18  formed therein. The plurality of conducting traces  16  terminate in copper pads  20  with plated holes  22  formed in their center. The traces  16  run under the channel  18 , as shown by the connecting lead  24 , which is enlarged for purposes of illustration, and connects to the conductors on the other side of the channel  18 . A single channel  18  is preferably formed to separate the circuit board  10  into a first section  26  and a second section  28 . The channel  18  is preferably formed by routing or sawing, however, it may be formed by any other suitable method. It should also be understood that any number of channels  18  may be formed in a circuit board  10  to separate it into more than two sections. Additionally, a number of channels  18  may be formed in close proximity to one another and still separate the circuit board  10  into two sections. In this embodiment, multiple small channels  18  are formed in the board allowing it to bend in a broad radius. 
     In the preferred embodiment, the channel  18  is formed such that only a thin remainder of the supporting layer  30  of the circuit board  10  is left as well as the conducting traces  16 . After the channel  18  has been formed in the board  10 , either the first section  26  or the second section  28  is bent. The board is preferably bent along the channel  18  so that the first section  26  is perpendicular to the second section  28 , i.e, that one of the sections is bent 90 degrees, such as shown in FIG.  2 . The bending is schematically illustrated by the arrow A. The allows the circuit board  10  to have both a horizontal main board and a vertical user interface board which are in both physical contact with one another as well as electrical communication. 
     Turning now to FIG. 3, another circuit board  10  is illustrated. The circuit board  10  also has an entire component assembly formed in its top surface  12 , including a plurality of conducting traces  16 . This circuit board is illustrated as a single sided board, however, it may be any type of circuit board, including a plated through hole board or printed through hole board. The components that comprise the assembly would be well known to those of ordinary skill in art depending upon the application for which the circuit board  10  is being used. 
     The circuit board  10  is subjected to local heating at  32 , as shown by the arrows B. The localizing heating is performed at a temperature sufficient to soften the circuit board all the way through. After the circuit board  10  been heated, either the first section  26  or the second section  28  is bent. The board is bent along the area subjected to localized heating  32  and is preferably bent so that the first section  26  is perpendicular to the second section  28 , i.e, that one of the sections is bent 90 degrees, such as shown in FIG.  4 . The bending is schematically illustrated by the arrow C. It should be understood that the board may be bent in the direction opposite the arrow C. The allows the circuit board  10  to have both a horizontal main board and a vertical user interface board which are in both physical contact with one another as well as electrical communication. 
     In any of the embodiments, the amount that either the first section  26  or the second section  28  can be bent may vary from greater than zero degrees to less than 180 degrees. If more than one channel  16  is formed in the board  10  then the bending process is repeated at each channel. In the case of circuit boards  10  with more than one conducting layer, holes can be drilled in the layer and used to shift all conducting traces  16  to one side in the area where the channel will be cut, such that the traces  16  will not be damaged. 
     Alternatively, after the circuit board  10  is assembled, it can be bent by both forming a channel  18  in the board  10  and by localized heating of the circuit board  10  at the channel  18 . The combination of the two methods allows the depth of the channel to be shallower and also allows for a lower temperature to be used to heat the circuit board  10 . The temperature and depth of the channel  18  can be balanced to match the application and characteristics of the supporting material from which the circuit board  10  is constructed. 
     Applications for the method and apparatus of the present invention include: (a) a horizontal main board with a vertical display/control board for use in vehicle audio products; (b) a horizontal main board with a vertical section for components attached to a vertical heat sink; (c) a horizontal main board with a vertical section for mounting of connectors; and (d) a vertical main board with a horizontal display/control board for use in connection with portable communication products, including hand-held and belt-clip products. 
     The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof; therefore, the illustrated embodiments should be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention.

Technology Classification (CPC): 8