Patent Publication Number: US-6210174-B1

Title: Electrical connection assembly

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to an electrical connector, and in particular to an electrical connection assembly comprising a connector soldered to two or more flexible circuit boards. 
     2. The Prior Art 
     Flexible circuit boards are frequently used in electrical devices having a very limited and complicated internal space, especially small-sized computers. The flexible circuit board is frequently equipped with an electrical connector for connection with other devices/parts. Conventionally, the flexible circuit board is secured to the connector by means of mechanical pressure applied thereon. FIGS. 1A and 1B of the attached drawings show a conventional connector, disclosed in Taiwan Patent Application Nos. 83102251, mounted to a flexible circuit board. The connector  2  comprises a pressurizing member  23  pivotally attached thereto by means of a trunnion  221 . The pressurizing member  23  has a contour  231  which, when rotated, exerts a gradually-increasing force on the flexible circuit board  1  thereby securely retaining the flexible circuit board  1  on contacts  22  of the connector  2  thereby establishing firm electrical connection therebetween. 
     Such a conventional assembly procedure is only suitable for connecting a single flexible circuit board to the connector. Current trends of the electronic industry increasingly require the mounting of two or more flexible circuit boards to a connector. It is therefore desired to provide an electrical connection assembly that is capable of connecting two or more flexible circuit boards to a connector. 
     SUMMARY OF THE INVENTION 
     Accordingly, an object of the present invention is to provide an electrical connection assembly for connecting two or more flexible circuit boards to an electrical connector. 
     Another object of the present invention is to provide an electrical connection assembly for connecting flexible circuit boards to an electrical connector by means of soldering with the soldering points exposed outside the connector for facilitating inspection. 
     To achieve the above objects, an electrical connection assembly in accordance with the present invention comprises a connector having a first portion defining a first row of contact receiving channels receiving and retaining first contacts therein and a second portion defining second and third rows of contact receiving channels receiving and retaining second and third contacts therein. Each contact has a soldering section extending beyond the connector. A first flexible circuit board and a second flexible circuit board are connected to the connector. The soldering sections of the first contacts are soldered to the first flexible circuit board by means of either through hole or surface mounting techniques. The soldering sections of the second and third contacts are respectively soldered to the second flexible circuit board by means of through hole and surface mounting techniques. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be apparent to those skilled in the art by reading the following description of preferred embodiments thereof, with reference to the accompanying drawings, in which: 
     FIG. 1A is a perspective view of a conventional electrical connector to which a flexible circuit board is mounted; 
     FIG. 1B is a cross-sectional view of the conventional connector of FIG. 1A; 
     FIG. 2A is a schematic view showing a single row of contacts of an electrical connector in accordance with a first embodiment of the present invention connected to a flexible circuit board by means of soldering; 
     FIG. 2B is a schematic view showing a single row of contacts of an electrical connector in accordance with a second embodiment of the present invention connected to a flexible circuit board by means of soldering; 
     FIG. 3 is a schematic view showing two rows of contacts of the electrical connector of the first embodiment connected to a flexible circuit board by means of soldering; 
     FIG. 4A is a cross-sectional view of the first embodiment of an electrical connection assembly; and 
     FIG. 4B is a cross-sectional view of the second embodiment of an electrical connection assembly. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the drawings and in particular to FIG. 4A, an electrical connection assembly in accordance with a first embodiment of the present invention comprises a connector  3 , a first flexible circuit board  4 , and a second flexible circuit board  5 . The connector  3  defines a receiving slot  36  in a first face thereof for receiving a mating connector or other devices (not shown). The connector  3  comprises an upper portion  31  and a lower portion  32  in which three rows of contacts  33 ,  34 ,  35  are retained and extend beyond a second face of the connector  3  for electrical connection with the flexible circuit boards  4 ,  5 . Understandably, those contacts may be arranged to function as signal, power or grounding contacts. 
     Also referring to FIGS. 2A and 3, the upper portion  31  of the connector  3  defines a first row of contact receiving channels  311  for receiving and retaining the first contacts  33  therein. The lower portion  32  of the connector  3  defines second and third rows of contact receiving channels  321 ,  322  for respectively receiving and retaining the second and third contacts  34 ,  35  therein while the upper portions of these two channels shares the same space with each other. In other words, the pair of second contact  34  and corresponding third contact  35  are commonly received within the same space in the lower portion  32  (FIGS.  4 A and  4 B). The contacts  33 ,  34 ,  35  comprise soldering sections  331 ,  341 ,  351  extending beyond the second face of the connector  3 , engaging sections  333 ,  343 ,  353  for electrically engaging with the mating connector, and intermediate sections  332 ,  342 ,  352  fixed in the connector  3  between the soldering sections  331 , 341 ,  351  and the engaging sections  333 ,  343 ,  353 . 
     As shown in FIGS. 2A and 4A, the soldering section  331  of each first contact  33  forms a right angle and is substantially normal to the first flexible circuit board  4 . Through holes  41  are formed in the flexible circuit board  4  in which the soldering sections  331  are received. Soldering is then performed to fix the soldering sections  331  of the first contacts  33  to the first flexible circuit board  4 . 
     Referring to FIGS. 3 and 4A, the soldering section  341  of each second contact  34  forms a right angle and is substantially normal to the second flexible circuit board  4 . The soldering sections  341  of the second contacts  34  extend through holes  51  formed in the second flexible circuit board  5  and are soldered thereto. The soldering section  351  of each third contact  35  forms two consecutive right angles thereby being offset therefrom in a parallel plane. The soldering sections  351  are engaged with conductive pads  52  formed on the second flexible circuit board  5  and surface mounted thereto. 
     Fixing the flexible circuit boards  4 ,  5  to the connector  3  by means of soldering eliminates the possibility of damaging the flexible circuit boards  4 ,  5  due to mechanical pressure and allows two or more flexible circuit boards to be simultaneously fixed to a connector. Furthermore, the soldering points are located outside the connector  3  thereby facilitating inspection and ensuring quality of the connection assembly. 
     FIGS. 2B and 4B show a second embodiment of the present invention wherein the first contacts  33  are surface mounted to the first flexible circuit board  4 . The soldering section  331 ′ of each first contact  33  forms two consecutive right angles and is thus offset therefrom in a parallel plane. The soldering sections  331 ′ are positioned on and surface mounted to conductive pads  42  formed on the flexible circuit board  4 . 
     The feature of the invention is to provide two first and second flexible circuit board respectively connecting to the contacts  33 ,  34 ,  35  of the upper portion  31  and of the lower portion  32  in the connector  3 . Additionally, the contacts of the lower portion further includes two type contacts  34 ,  35 , and thus the second flexible circuit board  5  provides two connection regions wherein the inner one, which is close to the connector  3 , is arranged to receive the through hole type second contacts  34  which is close to the center line of the connector, while the outer one is arranged to receive the surface mount type third contacts  35  which is close to the side wall of the connector. 
     It is also noted that each flexible circuit boards  4  and  5  includes an outward surface  47 ,  57  and an inward surface  48 ,  58  (FIG. 4A) wherein the inward surfaces  48 ,  58  of the boards  4  and  5  are facing to each other. The flexible circuit boards  4  and  5  are positioned parallel to each other, with a proper spatial relationship for not interfering with each other, at the back of the connector  3  close to the center line thereof, and the tail sections of the contacts  33 ,  34  ( 35 ) are arranged to extend in opposite directions and respectively approach the outward surfaces  47 ,  57  of the corresponding flexible circuit board  4 ,  5  from an exterior. With this arrangement, it is easy to correctly and reliably assemble the connector  3  and the corresponding flexible circuit board  4 ,  5  under sufficient inspection. 
     Although the present invention has been described with reference to the preferred embodiments, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.