US2972727A

US2972727A - Printed circuit assembly

Info

Publication number: US2972727A
Application number: US745879A
Authority: US
Inventors: Jr William H Flanagan; Robert W Fraser
Original assignee: United Carr Fastener Corp
Current assignee: United Carr Fastener Corp
Priority date: 1958-07-01
Filing date: 1958-07-01
Publication date: 1961-02-21
Anticipated expiration: 1978-02-21
Also published as: GB861426A

Description

Feb. 21, 1961 w. H. FLANAGAN, JR, ETAL 2,972,727

PRINTED CIRCUIT ASSEMBLY Filed July 1, 1958 A K/ 7 .J W u L N 7 N 1 .WA w E T O A S T N A A N AR H W Q .l M T R mm L u o a R fl j w fltl It! .w

PRINTED CIRCUIT ASSEMBLY William H. Flanagan, Jr., Wellesley, and Robert W. Fraser, Waltham, Mass., assignors to United-Carr Fastener Corporation, Cambridge, Mass., a corporation of Delaware t Filed July 1, 1958, Ser. No. 745,879

Claims. (Cl. 339-17) This invention relates to printed circuits and in particular to terminal assemblies for printed circuit boards.

The object of our invention is to provide a printed circuit female contact which is so adapted to be attached to a phenolic resin board or the like.

Another object of our invention is to provide a contact for staking into the circuitry of a printed circuit adapted for receiving an electronic component of the plug-in type.

With the advent of printed circuitry, a definite need has developed for an electrical contact for use with removable components and adapted for machine attachment into the circuitry without the use of solder.

The present invention involves a contact which may be readily inserted into a printed circuit and firmly attached thereto by machine methodsand adapted to receive the blade contacts of electronic components such as switches, relay contacts or the like.

Other objects of the invention will, in part, be obvious, and will, in part, appear hereinafter.

In the drawings:

Fig. l is a view in front elevation of the contact after assembly in an apertured panel;

Fig. 2 is an end view of a contact as seen from the right side before insertion; I

Fig. 3 is a view similar to Fig. 2 showing the contact positioned in the panel prior to deformation;

Fig. 4 is a view showing the first step in attaching the contact to the panel;

Fig. 5 is a view partly in elevation showing the contact assembled to the panel before the mandrel and die are withdrawn;

Fig. 6 is a top plan view of a portion of the panel showing the contact apertures;

Fig. 7 is a view in perspective of the contact;

Fig. 8 is a view in section partly in elevation of the contact assembled in the panel with a blade in position; and

Fig. 9 is a view in front elevation of the attaching mandrel and die.

Referring to the drawings, there is illustrated a female contact 10 which is adapted for assembly into an opening 12 in a printed circuit panel 14 having a copper circuit 16 on its upper surface.

In the preferred embodiment the opening 12 in the panel 14 is substantially rectangular in shape. The con-. tact It) is preferably formed of a generally U-shaped strip of resilient sheet metal and has a transverse medial bend 18 forming a pair of legs 20 which extend in the same general direction. The free ends 22 of the legs 20 are bent outwardly and away from each other defining flange portions and inclined downwardly with the terminal ends 24 preferably being serrated by a series of notches 26 for a purpose to be described hereinafter. The legs 20 are preferably trifurcated by a pair of channels 28 which extend from the bend 18 to a point 30 adjacent the free ends 22 so as to divide the legs 20 into three

shank portions

32, 34 and 36. The legs 20 2,972,727 Patented Feb. 21, 1961 of the innermost shank portion 34 are inclined toward each other to present a restricted area 38 adapted so that the

inner faces

40, 42 of the legs 20 may enter into frictional engagement with a blade 43 of a male component. Shoulders 44 are formed on the outermost shank portions 32 and 36 by a bowing outwardly of the legs 20 so as to diverge away from each other.

The contact is assembled into the opening 12 by a flexing inward of the shoulders 44 as it is axially inserted into the panel opening with the shoulders snapping outward and positioning the contact so that the panel is located between the shoulders and the terminal ends 24. At this point, a die 46 and a mandrel 48 are placed in superposed position within and surrounding the contact and when axial pressure is applied the headed mandrel 48 forces the free ends 22 of the legs downwardvwith the serrations formed by the notches 26 enter-. ing into biting engagement with the copper circuit 17 on the upper surface of the panel 14. Simultaneously the die 46, as shown in Fig. 5, forces the shoulders 44 into an abutting relation with the lower surface of the panel and so as to lie substantially perpendicular to the plane of the contact.

It willbe noted that the shoulders 44 and the terminal ends 24 are spaced a short distance vertically in relation to the axis of the contact. The distance will, of course, depend in part on the thickness of the panel 14 into which the contact is to be assembled as it can readily be seen that when the shoulders 44 are deformed, the panel is locked securely between them and free ends 22 of the legs 20.

Since certain other obvious modifications may be made in this device without departing from the scope of the invention, it is intended that matters contained herein be interpreted in an illustrative and not in a limiting sense.

We claim:

1. A printed circuit contact comp-rising a U-shaped shank with the free ends bent outwardly and away from each other defining flange portions, said shank being trifurcated defining laterally spaced leg portions, said flange portions inclined downwardly having notched terminal end portions, the inner of said laterally spaced leg portions having the walls bowed inwardly toward each other presenting a restricted area for frictional engagement with a blade to be inserted therein, the outer of said leg portions provided with axially deformable shoulders to cooperate with the flange portions and securing a panel imbedded therebetween.

2. A contact for assembly into a printed circuit panel comprising a U-shaped shank with the free ends bent outwardly and downwardly in the direction of bight, said shank being slotted from the bight to a point spaced from the free ends, thereby forming a plurality of leg portions, certain of said leg portions being inclined toward each other to present a restricted area for frictional engagement with a blade of a component to be inserted therein, said other leg portions being bowed outwardly forming shoulders spaced from said end portions, whereby said shoulders may be axially compressed to abut the lower side of said panel.

3. A female contact for assembly into an apertured printed circuit panel comprising a single piece of resilient sheet metal having a transverse medial bend forming legs laterally spaced from each other and extending in the same general direction, the free extremities of said legs being bent away from each other and inclined downwardly with the terminal ends serrated, said legsbeing trifurcated by vertical slots so as to present a plurality tive engagement with the free extremities of said legs to secure the contact within the panel.

4. A one piece resilient sheet metal contact adapted for axial insertion Within a complementary work aperture including a' portion bent back upon itself comprising legs joined by a bight and flanges extending outwardly from the free extremities, said legs having slots extending from the bight to a point adjacent said flanges defining a plurality of laterally spaced inner and outer shank portions, the inner of said shank portions being bowed inwardly defining a restricted area adapted for frictional engagement with a blade component to be inserted therein, shoulders intermediate the flanges and bight of the outer shank portions, said outer shank portions adapted for axial deformation with said shoulders cooperating with the flanges to retain a panel the'rebetween.

5. An electrical assembly comprising, in combination, a sheet metal contact and a printed circuit panel, said contact comprising a strip of sheet metal having a transverse medial bend forming resilient leg portions, the free ends of said leg portions bent outwardly away from each other and inclined downwardly in the direction of said bend forming flange portions, said leg portions being trifurcated by vertical slots extending from the bend to a point adjacent said flange portions, defining a plurality of sections, the inner of said sections having the walls deformed inwardly toward each other, shoulders formed on the other of said sections adapted for deformable engagement with one surface of said panel and cooperating with said flange portions to retain the panel therebetween.-

References Cited in the file of this patent UNITED STATES PATENTS 1,912,653 Olson June 6, 1933 2,229,989 Roby Jan. 28, 1940 2,623,086 Sampson Dec. 23, 1952 2,640,185 Alden May 26, 1953 2,641,748 Peters June-9, 1953