Device for securing a printed circuit board assembly

A board connecting structure for connecting an auxiliary circuit board to a main circuit board via a connector inside a case is described. A plate is connected to the auxiliary circuit board and a latch is hinge-coupled to the plate. The latch has a prong that fits into a groove formed in the case. One or more slight bumps and corresponding dimples are formed at surfaces of the plate and the latch. The clicks into place in the dimple, as the latch is rotated. At the same time, the prongs of the latch moves into the grove in the case so that the auxiliary circuit board is held in place. The auxiliary circuit board is easily installed into and removed from the connector.

CLAIM OF PRIORITY 
This application makes reference to, incorporates the same herein, and 
claims all benefits accruing under 35 U.S.C. .sctn.119 from an application 
for Board Connecting Structure earlier filed in the Korean Industrial 
Property Office on Jul. 16, 1996 and there duly assigned Serial No. 
21082/1996, a copy of the same being attached hereto. 
BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a PCB assembly connecting structure and, 
more particularly, to an apparatus a process for securing a printed 
circuit board assembly that allows for the easy installation and removal 
of a printed circuit board. 
2. Description of Related Art 
In a typical computer system, a connector to which an auxiliary device for 
extending a function is connected is electrically connected to a main 
circuit board. U.S. Pat. No. 3,767,974 for an Insertion and Extraction 
Lever for Printed Circuit Cards to Donovan Jr., et al and U.S. Pat. No. 
4,313,150 for a Latching Lever for Printed Circuit Boards to Chu, for 
example, each disclose the insertion and removal of a printed circuit 
board from a chassis without the use of screws or tools. In addition, they 
show a handle on the lever parts. I have found however, that there is a 
need for improving the process and structure used in the 
latching/unlatching process. 
SUMMARY OF THE INVENTION 
To overcome the above problems, it is an object to provide a board 
connecting structure by which an auxiliary circuit board can be easily 
connected to and disconnected from a connector. 
It is also an object to use protrusions and indentations to facilitate the 
connection and disconnection of the printed circuit board from the 
chassis. 
Accordingly, to achieve the above object there is provided a board 
connecting structure by which an auxiliary circuit board is installed into 
and removed from a connector which is electrically connected to a main 
circuit board inside a case, the board connecting structure including a 
plate connected to the auxiliary circuit board; and a hooking piece 
hinge-coupled to the plate and having an end portion to be inserted into a 
groove formed at the case, in which at least one coupling protrusion is 
formed on one of the surfaces of the plate and the hooking piece facing 
each other, and at least one coupling indentation into which the coupling 
protrusion is fitted is formed on the other of the surfaces of the plate 
and the hooking piece.

DETAILED DESCRIPTION OF THE INVENTION 
Turning now to the drawings, FIGS. 1 and 2, a board connecting structure 
has a plate 4 installed at one side of an auxiliary circuit board 2 and a 
hooking piece 5 which is hinge-coupled to plate 4. A groove 1a into which 
hooking piece 5 is inserted is formed on case 1. A connecting terminal 2a 
of auxiliary circuit board 2 is plugged into a connector 3 which is 
electrically connected to a main circuit board (not shown) inside case 1. 
Plate 4 is coupled to auxiliary circuit board 2 by a coupling means such 
as a screw 7. Pin 6 is inserted through pin hole 4a and through hole 5a. 
Auxiliary circuit board 2 to which plate 4 is coupled is connected to 
connector 3 as follows. First, connecting terminal 2a of auxiliary circuit 
board 2 is inserted into connector 3. Then, hooking piece 5 is inserted 
into groove 1a of case 1 and hooking piece 5 is fixed to plate 4 by bolt 
8. Thus, auxiliary circuit board 2 is prevented from disconnecting from 
connector 3 due to impact from the outside. 
Referring now to FIGS. 3 and 4, a board connecting structure of the present 
invention includes a plate 14 coupled to an auxiliary circuit board 12 by 
screws 17 and latch 15 hinge-coupled to plate 14. A connecting terminal 
12a of auxiliary circuit board 12 is plugged into a connector 13 which is 
electrically connected to a main circuit board (not shown). Latch 15 is 
inserted into a groove 11a formed in a case 11. 
It is a characteristic feature of the present invention that at least one 
dimple, or recess, 15b (see FIG. 4) is formed on the inner surface of 
hooking piece 15 facing a surface of plate 14 and at least one bump, or 
plug, 14c is formed on the surface of plate 14 at a position corresponding 
to coupling indentation 15b. Alternatively, the dimple may be formed on 
plate 14 and the bump may be formed on latch 15. Latch 15 is formed of an 
elastically deformable, flexible material such as synthetic resin so that 
bump 14c fits into dimple 15b when the two coincide. Alternatively, bump 
14c is formed of a flexible material such as synthetic resin. Plate 14 and 
latch 15 are hinge-coupled by a pin 16 which penetrates hollow 14a and 
bore 15a formed at plate 14 and latch 15, respectively. Thus, latch 15 is 
rotatable around pin 16 within a predetermined angle with respect to plate 
14. Also, handle 15d is formed in latch 15. 
The installation of the board connecting structure according to the present 
invention will be now described as follows. First, the board connecting 
structure is advanced such that connecting terminal 12a of auxiliary 
printed circuit board 12 can be inserted into connector 13 and 
simultaneously latch 15 can be inserted into groove 11a formed in case 11. 
In this state, handle 15d of latch 15 is pressed downward to allow latch 
15 to pivot around pin 16 so that prong 15c of latch 15 enters groove 11a 
in case 11. As latch 15 rotates, bump 14c formed in plate 14 contacts a 
surface around dimple 15b formed on latch 15. Thereafter, when latch 15 is 
continuously pressed to further rotate with a force greater than the 
repelling power generated by bump 14c, the bump 14c fittingly inserts into 
dimple 15b since latch 15 is formed of a flexible material. At the same 
time, the inner surface of latch 15 contacts the surface of plate 14 so 
that rotation of latch 15 stops, as shown in FIG. 5b. Dimple 15b and bump 
14c undergo elastic deformation upon engagement. Surface 15e of latch 15 
mates with interior mating surface 11b of case 11 upon engagement, 
As is shown in FIG. 5a, when latch 15 is rotated in the opposite direction 
in order to remove the printed circuit board connecting structure from the 
main circuit board, prong 15c of latch 15 comes out from groove 11a of 
case 11 while bump 14c is separated from from dimple 15b by forces caused 
from undergoing elastic deformation. Then, auxiliary circuit board 12 is 
unplugged from connecter 13. 
The foregoing paragraphs describe process and structure using protrusions 
and detents to facilitate latching and unlatching of a lever piece on the 
circuit board. As described, the board connecting structure of the present 
invention enables an auxiliary circuit board can be easily installed into 
and removed from the connector by the action of coupling the coupling 
protrusion and the coupling indentation by rotating the hooking piece.