US3147059A

US3147059A - Electrical connection

Info

Publication number: US3147059A
Application number: US30162A
Authority: US
Inventors: Gluck William
Original assignee: UNITED INTERNATIONAL DYNAMICS CORP
Current assignee: UNITED INTERNATIONAL DYNAMICS CORP
Priority date: 1960-05-19
Filing date: 1960-05-19
Publication date: 1964-09-01
Anticipated expiration: 1981-09-01
Also published as: GB950109A

Description

p 1, 1964 w. GLUCK ELECTRICAL CONNECTION 3 Sheets-Sheet 1 Filed May 19, 1960 FIG. 2

FIG. I

FIG. 5"

I FIG.6

INVENTOR. WILLIAM GLUCK ATTORNEYS Sept. 1, 1964 w. GLUCK 3,147,059

ELECTRICAL CONNECTION Filed May 19, 1960 3 Sheets-Sheet 2 42 \IIIII IIIIIIIT!IIII FIG.8

IN VEN TOR.

WILLIAM GLUCK ATTOR N EYS Sept. 1, 1964 w. GLUCK 3,147,059

ELECTRICAL CONNECTION Filed May 19, 1960 3 Sheets-Sheet 3 JNVENTOR. FIG. |3 WILLIAM GLUCK ATTORNEYS United States Patent 3,147,059 ELECTRICAL CONNECTIGN William Gluck, Waltham, Mass., assignor to United International Dynamics ,Corp., Boston, Mass, a corporation of Massachusetts Filed May 19, 1960, Ser. No. 30,162 6 Claims. (Cl. 339193) The present invention relates in general to removably establishing electrical connection and more particularly concerns sockets for receiving electrical components and the novel contacts comprising the sockets. The novel sockets are sturdy, compact and adaptable for automatic insertion into printed circuit boards. The pins connected to an external component may be easily inserted into and removed from the novel socket contacts, yet positive and firm electrical and mechanical contact is assured for many insertions and withdrawals.

A typical prior art miniature tube socket comprises contacts of conducting material having a generally U- shaped cross-section with the legs of the U pointing inward to resiliently grip an inserted conducting pin inserted into the contact. These sockets have a number of disadvantages. Tube pins and socket contacts must be in nearly perfect alignment. Great pressure is often necessary to insert a tube into the socket when the socket is new. As a result, it is not uncommon to bend one or more tube pins during an initial attempt at insertion. This introduces annoying and costly delays because the pin must be straightened before the tube can be inserted into the socket. In addition, bending weakens the pin and may cause strains in associated structure. After a number of insertions and withdrawals have been made in a particular socket, a tube may be inserted more easily, but the establishment of electrical contact is not infrequently unreliable so that defective performance of an associated circuit is due to poor contact between the pin and socket contact. The disadvantages of poor contact are obvious.

The disadvantages enumerated above are serious enough for conventional sockets secured to a chassis by rivets or screws and nuts. However, sockets using such contacts and adapted for automatic insertion into printed circuit boards are complex structures. These structures typically comprise a pair of spaced parallel supporting bases which are reservoirs for socket-deteriorating moisture accumulation, the accumulated moisture also reducing the resistance between contacts. The large number of parts in such sockets adds to the cost and complexity of manufacture.

Accordingly, it is an important object of the present invention to provide a socket for establishing electrical connection to a removeable circuit component which freely admits and releases the component when desired but snugly engages each contact pin of the component when the component rests in the socket.

It is an object of the invention to provide a socket in accordance with the preceding object of simple compact form which is relatively easy to fabricate, low in cost and yet retains the desired properties for an exceptionally large number of withdrawals and insertions.

3,147,059 Fatented Sept. 1, 1964 a with opposed ears extending outward from and generally It is still another object of the invention to provide a A perpendicular to the first portion legs. These ears are preferably in intimate contact with one side of the supporting base while the other side of the base is in intimate contact with an adjacent edge of the second portion to restrict relative movement between the contact and the base.

In one form of the socket, the openings are spaced along a line, space being conserved by arranging the length of at least one opening to intersect that line and a line collinear with the length of the adjacent opening. Preferably, the lengths of alternate openings are generally parallel.

Each contact is preferably formed from a generally T-shaped sheet of conductive material preferably formed with an opening substantially along the axis of symmetry of the stern portion of the T just above the boundary between the stem portion and the cap portion of the T. The cap portion includes two pairs of slits. A first pair of slits extends perpendicular to and from that edge of the cap portion substantially collinear with said boundary. A second pair of slits extends perpendicular to and inwardly of respective ones of the first pair of slits.

Numerous other features, objects and advantages of the invention will become apparent from the following specification when read in connection with the accompanying drawing in which:

FIGS. 1 and 2 are side and front views respectively of one embodiment of a contact according to the invention;

FIGS. 3 and 4 are side and front views respectively of another embodiment;

FIGS. 5 and 6 show blanks from which the abovementioned contacts are formed;

FIG. 7 is a perspective view of a tube socket according to the invention;

FIG. 8 shows a view of the novel tube socket inserted into a printed circuit board;

FIG. 9 shows a top view of a printed circuit board with openings arranged to accommodate the novel socket of FIG. 7;

FIG. 10 is a top View of a novel transistor socket according to the invention;

FIG. 11 is a sectional view through section 9-9 of FIG. 8;

FIG. 12 is a top view of a socket suitable for receiving a replaceable component having seven coplanar pins; and

FIG. 13 is a side view of the structure shown in FIG. 12.

With reference now to the drawing and more particularly FIGS. 1 and 2 thereof, there is shown a representative embodiment of a contact according to the invention. The contact is made of conducting material having a lower portion 11 and upper portion 12 generally separated by an opening 13 and both being of generally U-shaped cross section. An opening 13 is formed along a part of the boundary between the upper and lower portions.

The upper portion 12 is formed with a pair of downwardly extending

opposed legs

14 and 15 extending into the volume bounded by extensions of the sides of the upper portion 12. The

legs

14 and 15 are formed with curved ends that have convex surfaces resiliently urged together in normal tangential contact along the vertical longitudinal 3 axis common to the upper portion 12 and lower portion 11. The legs are cantilevers bendable about respective axes that are generally perpendicular to the vertical longitudinal axis, the said axes being spaced from the curved ends by straight portions of the respective legs.

The upper portion 12 is also formed with

ears

21 and 22 extending outward from and generally perpendicular to

legs

14 and 15, respectively. The

ears

21 and 22 coact with the

upper edges

23 and 24, respectively, of

sidewalls

16 and 17, respectively, for snugly engaging opposite sides of an insulating supporting base containing the contacts.

Sidewalls

16 and 17 are formed with

slots

25 and 26, respectively. The

horizontal edges

27 and 23 adjacent to

slots

25 and 26, respectively, are adapted to rest upon the top surface of a printed circuit board. The downwardly sloping

edges

31 and 32 adjacent to

slots

25 and 26, respectively, allow the contact to seat properly in printed circuit boards of different thicknesses. The downwardly sloping

edges

33 and 34 function to guide the contact through the opening in the printed circuit board when the socket is initially inserted.

Referring to FIG. 5, there is shown a blank suitable for being formed into the contact shown in FIGS. 1 and 2. The same reference numerals identify corresponding portions in FIGS. 1, 2 and 5. The blank is generally T- shaped as shown and made of Phosphor bronze or other suitable conducting material having some resilience.

The upper and lower portions 12 and 11 comprise the cap and stem, respectively, of the T. The cap portion is formed with

vertical slits

35 and 36 extending from and generally perpendicular to the lower edges of

legs

14 and 15, respectively, these edges being extensions of the boundary between the cap and stem of the T. The upper edges 23 and 24 of

sidewalls

16 and 17, respectively, appear as slits extending inwardly from and generally perpendicular to the

vertical slits

35 and 36, respectively. By the use of suitable punches and dies, the blank is bent about its vertical axis of symmetry so that the

sidewalls

16 and 17 and the

legs

14 and 15 are opposed, the bottom portions of

legs

14 and 15 being crimped together while

cars

21 and 22 are bent over so that the structure appears as shown in FIG. 2. The corners near

edges

27 and 28 may be bent inwardly slightly. The corners at

edges

23 and 24 may be bent outward slightly to provide a better gripping means for engaging the lower surface of the insulating base. The opening 13, while not essential, facilitates bending sidewalls into opposed generally parallel relationship because the depending legs obstruct the volume where a projection on a punch might otherwise be inserted and function as a fulcrum during bending.

Referring to FIGS. 3 and 4-, there is shown side and front views, respectively, of another embodiment of a contact according to the invention. Since the structure of this contact is similar in principle to the structure of the contact described above in connection with FIGS. 1, 2 and 5, portions of the former contact which correspond to por tions of the latter contact are designated by the same reference numeral with an appended prime. The description above is applicable to the contacts in FIGS. 3 and 4 by considering reference to portions in FIGS. l-2 as referring to the portions designated by the same reference numeral primed in FIGS. 3-4.

The contact shown in FIGS. 3-4 is formed with the lower portion 11' being curved away from the upper portion 12'. This is advantageous in certain applications where it is desired to have a socket with bottom connection points which pass through the printed circuit board separated by a greater distance than the pin connections of the component supported in the socket.

For example, a perspective view of such a socket is shown in FIG. 7 for use in supporting a nine pin miniature tube. The socket of FIG. 7 is shown in position in a printed circuit board in FIG. 8. The arrangement of openings in the printed circuit board as shown in FIG. 9

are spaced to accommodate either a prior art tube socket, or the novel tube socket shown in FIG. 7.

The structure in FIGS. 3 and 4 also includes a small tab 41. The purpose of tab 41 is to hold the socket in the printed circuit board prior to soldering. Tab 41 effects a snap action when the socket is inserted into the printed circuit chassis. The printed circuit chassis with the inserted socket is then usually dip soldered.

Another feature of the contact of FIG. 3 resides in the horizontal edges 27' and 28'. While the contact of FIG. 1 is satisfactory for many purposes, pressing such contacts through a punched hole in an insulating supporting base will sometimes result in an unsatisfactory socket if the edges of the hole punched in the base are rough. The sharp edges 27 and 28, bent inward to facilitate slipping through the hole in the base, sometimes scrape and chip rough-edged holes, especially since the burr on the stamped contact is on the outside.

This problem is materially reduced with the contact of FIG. 3 because the horizontal edges 27' and 28' pass through the hole in the base at an angle which prevents cutting engagement with the edges of the hole as these edges follow the lead of the smooth curved surface of lower portion 11' during insertion.

This blank shown in FIG. 6 may be bent to form the contact of P165. 3 and 4 in a manner similar to the bending operation described above with the exception that the curving of the lower portion 11 is also accomplished during the bending operation.

Referring to FIG. 7, there is shown a nine pin miniature socket in which nine of the contacts of the type shown in FIGS. 3 and 4 are arranged about a circle in an insulating supporting base 42 having a central opening 44 and a keying slot 45. The contacts 43 drop into mating openings 46, shown in FIG. 9, in a printed circuit board 47.

Details of a contact 43 resting in the printed circuit board are shown in the cutaway view of FIG. 8. The edge 28 rests upon the top surface of the printed circuit board 47 and the intersection of edges 32' and 34 bears against the inner surface of the opening 46 while tab 41 snaps out to grip the under surface of board 47 to insure a tight mechanical fit. FIG. 8 also shows the insulating supporting base 42 intimately contacted by an ear such as ear 22 on the top surface and by the upper edge 24' of lower portion 12 at its bottom surface.

Referring to FIGS. 10 and 11, there are shown a top view and a side sectional view, respectively, of a novel socket according to the invention especially suitable as a transistor socket. The contacts 51-53 are shown mounted in an insulating support base 54 accommodating pins 55-57, respectively, of a transistor. Pins 55-57 are aligned along a straight line which coincides with the length of the

opening accommodating contacts

51 and 53 while being perpendicular to the length of the opening which accommodates contact 52.

Referring to FIG. 12, there is shown a socket capable of accommodating a replaceable circuit component which might comprise an interstage coupling network and have seven pins aligned along a straight line 61 which passes through the urged-together upper

portion contact legs

14 and 15' of each contact 62, the contacts 62 being accommodated in openings in an insulating supporting base 63. The length of each of these openings makes an angle of approximately 45 with the line 61 and approximately with the length of adjacent openings, alternate openings being substantially parallel to one another. This is an advantageous arrangement because the differently oriented contacts '62 form a compact arrangement with the spaced rows of legs providing a firm support for the socket upon a printed circuit board.

There has been described novel sockets and contacts which are low in cost, relatively easy to fabricate, compact, and suitable for automatic insertion into printed circuit boards. Replaceable components may be easily inserted into and withdrawn from the sockets but are firmly held in place to continuously provide good conductive contact despite numerous removals and withdrawals of components.

The specific embodiments described herein are by way of example only. It is evident that those skilled in the art may now make numerous modifications of and departure from the specific embodiments and techniques described herein without departing from the inventive concepts. Consequently, the invention is to be construed as limited only by the spirit and scope of the appended claims.

What is claimed is:

1. A socket comprising,

a supporting insulating base consisting of a disc of uniform thickness formed with a plurality of openings each being of uniform cross section and snugly accommodating an electrical contact for establishing a conductive path between said contact and an insertable conductor,

each of said contacts comprising,

a structure of conducting material having a first portion of generally U-shaped cross section and a second portion connected to said first portion and also of generally U-shaped cross section,

said first and second portions being spaced along a common longitudinal axis generally perpendicular to said disc,

said first portion having a pair of opposed legs formed with curved ends that have convex surfaces resiliently urged toward normal tangential contact along said common longitudinal axis whereby said legs may be urged apart when said insertable conductor is forced therebetween along said common axis to snugly accommodate the latter and establish conductive contact therewith,

said legs being cantilevers bendable about respective axes in said first portion generally perpendicular to said common longitudinal axis and generally parallel to said disc,

said axes being spaced from said curved ends by straight portions of the respective legs,

said curved ends and the lower sections of said straight portions extending outside the thickness dimension of said disc and being disposed below the underside of said disc,

the sole means for supporting each of said contacts in said base being the portion of said base immediately adjacent to a respective opening.

2. A socket in accordance with claim 1 wherein said first portion of each contact is formed with opposed ears extending outward from and generally perpendicular to said legs,

said ears being in intimate contact with one side of said supporting base,

a part of the end of said second portion near said first portion being in intimate contact with the other side of said supporting base to restrict relative movement between each contact and said base.

3. A contact in accordance with claim 1 wherein said first portion is formed with opposed ears extending outward from and generally perpendicular to said legs.

4. A socket in accordance with claim 1 wherein said openings are spaced along a circle.

5. A socket in accordance with claim 1 wherein said openings are closely-spaced along a line, each opening having a length greater than its width, the length of at least one opening intersecting said line and a line collinear with the length of the adjacent opening.

6. A socket in accordance with claim 5 wherein the lengths of alternate ones of said openings are substantially parallel.

References Cited in the file of this patent UNITED STATES PATENTS 1,671,226 Caruso May 29, 1928 2,304,808 Draving Dec. 15, 1942 2,458,097 Penfold Jan. 4, 1949 2,480,059 Stickney Aug. 23, 1949 2,482,990 Olson Sept. 27, 1949 2,602,988 Klym July 15, 1952 2,683,259 Lowther July 6, 1954 2,745,081 Ofrerman May 8, 1956 2,747,169 Johanson May 22, 1956 2,793,353 Del Camp May 21, 1957 2,793,354 Heimbach May 21, 1957 2,817,067 Paradise Dec. 17, 1957 2,825,881 Del Camp Mar. 4, 1958 2,857,582 Wintriss Oct. 21, 1958 2,861,253 Johanson Nov. 18, 1958 2,908,885 Deakin Oct. 13, 1959 2,972,727 Flanagan et a1 Feb. 21, 1961 FOREIGN PATENTS 776,881 Great Britain June 12, 1957

Claims

1. A SOCKET COMPRISING, A SUPPORTING INSULATING BASE CONSISTING OF A DISC OF UNIFORM THICKNESS FORMED WITH A PLURALITY OF OPENINGS EACH BEING OF UNIFORM CROSS SECTION AND SNUGLY ACCOMMODATING AN ELECTRICAL CONTACT FOR ESTABLISHING A CONDUCTIVE PATH BETWEEN SAID CONTACT AND AN INSERTABLE CONDUCTOR, EACH OF SAID CONTACTS COMPRISING, A STRUCTURE OF CONDUCTING MATERIAL HAVING A FIRST PORTION OF GENERALLY U-SHAPED CROSS SECTION AND A SECOND PORTION CONNECTED TO SAID FIRST PORTION AND ALSO OF GENERALLY U-SHAPED CROSS SECTION, SAID FIRST AND SECOND PORTIONS BEING SPACED ALONG A COMMON LONGITUDINAL AXIS GENERALLY PERPENDICULAR TO SAID DISC, SAID FIRST PORTION HAVING A PAIR OF OPPOSED LEGS FORMED WITH CURVED ENDS THAT HAVE CONVEX SURFACES RESILIENTLY URGED TOWARD NORMAL TANGENTIAL CONTACT ALONG SAID COMMON LONGITUDINAL AXIS WHEREBY SAID LEGS MAY BE URGED APART WHEN SAID INSERTABLE CONDUCTOR IS FORCED THEREBETWEEN ALONG SAID COMMON AXIS TO SNUGLY ACCOMMODATE THE LATTER AND ESTABLISH CONDUCTIVE CONTACT THEREWITH, SAID LEGS BEING CANTILEVERS BENDABLE ABOUT RESPECTIVE AXES IN SAID FIRST PORTION GENERALLY PERPENDICULAR TO SAID COMMON LONGITUDINAL AXIS AND GENERALLY PARALLEL TO SAID DISC, SAID AXES BEING SPACED FROM SAID CURVED ENDS BY STRAIGHT PORTIONS OF THE RESPECTIVE LEGS, SAID CURVED ENDS AND THE LOWER SECTIONS OF SAID STRAIGHT PORTIONS EXTENDING OUTSIDE THE THICKNESS DIMENSION OF SAID DISC AND BEING DISPOSED BELOW THE UNDERSIDE OF SAID DISC, THE SOLE MEANS FOR SUPPORTING EACH OF SAID CONTACTS IN SAID BASE BEING THE PORTION OF SAID BASE IMMEDIATELY ADJACENT TO A RESPECTIVE OPENING.