US 3750085 A
An electrical connector for an integrated circuit package comprising two parts movable toward and away from each other. The lower part has cavities containing resilient contact which are made to flex when the two connector parts are brought together. An integrated circuit package is placed in the upper part with its terminals extending into the cavities in the lower part, and pressure is applied to bring the two parts together, flexing the socket contacts into pressure contact with the terminals of the integrated circuit package. Hook type latches are provided to hold the two parts together.
Description (OCR text may contain errors)
United States Patent 1191 Cooper PLUG AND SOCKET CONNECTORS AND SOCKETS THEREFOR  inventor: Frederick David Cooper, Runcorn,
England  Assignee: S.D.C. Products (Electronics) Limited, Runcom, England 22 Filed: Mar. 11, 1971 21 Appl. No.: 123,363
 Foreign Application Priority Data Aug. 18, 1970 Great Britain 39,655/70  U.S. Cl. 339/75 M, 339/17 CF, 339/174  int. Cl H0lr 13/54  Field of Search 339/75, 253, 17 C, 339/17 CF, 174
 References Cited UNITED STATES PATENTS 10/1958 Vanderpool 339/75 MP 7/1967 Aksu et a1. 339/75 MP 1 1 July 31, 1973 10/1969 Krum et a1. 339/75 MP 3/1971 Kehagioglou 339/75 MP OTHER PUBLICATIONS IBM Technical Disclosure Bulletin, Socket Connector, M. L. Brain, Vol. 13, No. 6, Nov. 1970, p. 1549.
Primary Examiner-Marvin A. Champion Assistant Examiner-Wil1iam F. Pate, I11 Attarney Stevens, Davis, Miller & Mosher [5 7] I ABSTRACT An electrical connector for an integrated circuit package comprising two parts movable toward and away from each other. The lower part has cavities containing resilient contact which are made to flex when the two connector parts are brought together. An integrated circuit package is placed in the upper part with its terminals extending into the cavities in the lower part, and pressure is applied to bring the two parts together, flexing the socket contacts into pressure contact with the terminals of the integrated circuit package. Hook type latches are provided to hold the two parts together.
5 Claims, 12 Drawing Figures PATENIED JUL 31 I915 SHEET 1 [IF 5 PATENI0 JUL 3-1 I875 I SHEET 2 [IF 5 Fla. .7
PATENIED JUL 3 1 I975 PLUG AND SOCKET CONNECTORS AND SOCKETS THEREFOR This invention relates touelectrical'plug and socket connectors and in particularto sockets for receiving electrical terminals.
In a conventional design of electrical plug and socket, the plug pins are inserted into corresponding apertures in the socket and generally force open a set of cantilever leaf springs forming a socket terminal and which bear onto the pins thereby forming a conducting path between the mating pin and socket members. This design has the disadvantage that the contact pressure between the plug pins and socket terminals is limited since too high a pressure would impede the insertion and withdrawal of the plug pins. This problem is particularly serious with multipole plugs and sockets. Also, the area of contact between the mating members is relatively small which leads to a relatively high contact resistance.
According to one aspect of the invention, a socket for an electrical connection comprises a first part, at least one contact mounted in the first part, and a second part movable relative to the first part from a first position to a second position to move the contact to a position to engage a plug contact inserted into the socket.
From another aspect of the invention a plug and socket connector comprises a plug having at least one contact, a socket having an aperture and a contact for each plug contact, the plug and socket being relatively movable from a first position in which the plug and socket contacts are out of engagement to a second position in which they are in engagement, the contact coming into engagement only during a latterpart of the relative movement.
Preferably the socket terminal(s) flex in a direction transverse to the movement of the plug terminal(s).
The invention may be performed in various waysand several embodiments will now be described by way of example with reference to the accompanying diagrammatic drawings, in which:
FIG. 1 is a perspective view of an assembled socket and plug in the form of an integrated circuit package;
FIG. 2 is an exploded view of the socket of FIG. 1;
FIG. 3 is a section through the socket of FIG. 2 with the socket terminals in disengaged position;
FIG. 4 is a section similar to FIG. 3 but showing the terminals of the package partially inserted;
FIG. 5 is a view similar to FIG. 4 with the package terminals fully inserted;
FIG. 6 is a perspective view partly in section of the arrangement of FIG. 1;
FIG. 7 is a view similar to FIG. 3 of another embodiment;
FIG. 8 is a view similar to FIG. 5 of the FIG. 7 arrangement;
FIG. 9 is a view similar to FIG. 7 ofa further embodiment;
FIG. 10 is a view similar to FIG. 8 of the FIG. 9 arrangement;
FIG. 11 is a view similar to FIG. 7 ofa fourth embodiment; and
FIG. 12 is a side elevation showing one form of retaining means.
Referring to FIGS. 1 to 6, a multipole socket comprises a base portion 10 formed with two rows of square cross-section apertures 11 therein. Each aperture 11 is arranged to receive a terminalor contact 12 which is a generally T-shaped piece of flat stamped metal sheet having a wider upper portion 13 and a narrower stem portion 14. A top or lidportion 1'5 is formed from thermoplastic material and with two rows of square crosssection apertures 16 and a number of downwardly extending circular section pins 17 for engagement-in apertures 18 in the base portion to locate the base portion and top portion in relation to each other.
The base portion is moulded in a thermoplastic material with the two shoulders 19 of each of the terminals 12 abutting the bottom wall 20 of the respective aperture 11 and so that the portions of thestems '14 adjacentthe widerportions 13 of the terminals are firmly held in the base portion.
The free end portions 21 of the'stem portions l4 extend from the base portion andmay for example have electrical leads soldered to them, or'may be soldered to a printed circuit board.
The underside 22 of the lid 15 is formed with a plurality of V-shaped'notches23 respectively adjacent the apertures 16. Thelid is initially assembledwith the base as shown in FIG. 3 and in this position theunderside 22 of the lid is spaced from the top surface 24 of the base,
with pins 17 engaged in apertures 18, and with the upper ends 25 of the terminals engaged in the bases of the notches 23. The upperportions 13 of the terminals 12 are slightly bowed. The bases of the notches'are in linewith the associated stem portions 14. The parts are held against separation from the FIG. 3 position by clips shown diagrammatically at-26 which are integral with the base 10.
The socket is now ready to receive the terminals of a plug or plug-type component. One such component is an integrated circuit package having parallel flat metal terminals or contacts 30 extending therefrom and connected tocircuits and component such as resis' tors, capacitors, etc. in the package body 31.
The terminals 30 are inserted into apertures 16 and into apertures 1 l. The apertures 16 are tapered as they extend towards the base to provideinclined surfaces 32 which can guide the terminals 30.'The inner faces of the terminals 30 engage or are closely'spaced from side faces 33, 33a of the apertures 11 so that there is little or no force opposing the insertion of the terminals 30 into the socket. At one side the terminals 30 are adjacent an inner face 33 and at the other side adjacent an outerface 33a. A position such as that shown in FIG. 4 is reached with terminals 30 spaced from terminals portions 13. Further engaging movement of the terminals 30 into the apertures 11 causes the package body 31 to engage the lid 15, and the lid then moves with the package body towards the base. This causes the terminal portions 13 to bow or flex further until the convex surfaces 34 of the tenninal portionsl3 at one side row engage the outwardly facing surfaces of the terminals 30 and at the other side row engage the inwardly facing surfaces of terminals 30. Further movement to a position (FIG. 5) in which the lid engages the base causes the terminals 30, 13 to engage over a substantial portion of the length of apertures 11, the terminals being firmly urged together. The parts are held in this fully engaged position by hooks, such as hooks 35 (only one shown), see FIG. 6.
By suitable selection of the thickness of terminals 12 and the length of the wider portion 13, the extent to which the terminals engage can be varied.
When the hooks 35 are released, the package body and terminals 30 may be withdrawn, the lid being moved by the power terminals 12 to the FIG. 3 position. There is thus little or no force opposing the withdrawal of the terminals 30.
An alternative arrangement is shown in FIG. 7 and 8 where parts similar to those of FIGS. 1 to 6 have the same reference numerals with suffix a. In this case the pins 17a and apertures 18a are located centrally. The notches 23a open into the apertures 16a. The upper wider portions 13a of the terminals 12a are bowed, at 40 and 41, in two opposite directions. On insertion of the terminals 30a, the terminals 300 are in line with the stem portions 21a, instead of being offset as in the arrangement of FIGS. 1 to 6, providing a more compact design. Terminals 30a are omitted from the figures whch show the bowing of the terminals as the lid is brought to the closed position.
Another embodiment is shown in FIGS. 9 and 10, in
which parts similar to those of FIGS. 1 to 6 have the same reference numerals with suffix b. In this arrangement, the lid 15!; is formed with opposed wing extensions or latches having a lower downwardly extending portion 50 formed with an inwardly directed tooth 51, and an upper upwardly extending portion 52'. The upper portions of the sides of the base b are formed with spaced notches 53 into which the teeth 51 may engage. The lid b includes an aperture 59 which can accept a single plug contact 54 preferably of square section. A single length of flat metal strip 55 has its ends engaged in notches 23b in the lid and is shaped to extend as a terminal 57 through an aperture 56 in the base 10b and to be bowed inwardly on opposite sides of the contact 54. The latches hold the parts in the unengaged position (FIG. 9) but on downward pressure being applied to the plug or lid, the teeth 51 .disengage from the upper notches 53 and the lid moves to the fully engaged position (FIG. 10) whereupon the teeth snap into engagement with the lower notches 53 to hold the parts against relative separating movement. The plug 54 is engaged on two opposite sides by the bowed portions of the strip 55.
The latches may be disengaged by inwardly directed pressure applied by thumb and finger to the portions 52. The upward force produced by the stress in the contacts 55 urges the lid and plug upwardly and the portions 52 may then be released whereupon the teeth re-engage in the upper notches 53.
An electrical conductor or component may be attached to the upper portion 58 of the plug,
FIG. 11 shows a three pin plug and socket for domestic use and parts similar to those in FIGS. 1 to 6 have the same reference numerals with suffix c.
The lid 15s is formed with three square section pin contacts 60, 61, 62, a larger one 60 being for connection to earth. The base carries three terminals 30c, each with two opposed bowed portions 63, 64. Each terminal 300 has a flat portion 65 held against an inner surface of the base by a screw 66 which passes through the base and to which an external lead or component can be connected.
In the unengaged position shown the pins 60, 61, 62 are not in engagement with the terminals 30c but the contact chamber 67 is completely surrounded by insulating plastics material. This provides safety, particularly at high voltages. Lateral flanges 68 on the lid 15c engage shoulders 69 on the base to prevent the lid being separated from the base. When the lid is pushed down, the terminals 63, 64 bow inwards to engage the pins, as before, and latch member 70 integral with the base engage over the top surface 71 of the lid to hold the parts in the engaged position. The latch members 70 can be pushed apart to allow the parts to return to the FIG. 11 position.
FIG. 12 shows one form of means for retaining the lid and base in engaged position.
Hooks or clips are moulded integrally at the ends of the baseand in'clude inwardly extending lips 81 at their upper ends. In the engaged position the lips engage over the top surface of the lid, The lips can be urged apart slightly laterally ofi' the top surface and the lid 15 is moved outwardly by the socket terminals until surfaces 82 rebated in the lid engage the lips 81 with the lid in the disengaged position. The lid and base are thus held in disengaged position.
It will be appreciated that with the arrangments described the plug terminals and the socket terminals come into engagement only during the latter part of the movement of the lid towards the base, This is another safety feature.
It will also be appreciated that in the engaged positions (FIGS. 5, 8, 10) the plug(s) are firmly gripped by the bowed socket contacts which bias the lid away from the base. I
On release of the clips, the lid and plug are urged to wards the disengaged position by the socket contacts.
Furthermore, as the plug terminals encounter little or no opposition to their insertion into the socket until the lid is moved towards the base, there is little or no tendency for the sometimes fragile plug terminals to be broken or damaged during insertion.
In any of the above arrangements the socket contacts may be stressed in the disengaged position (such as FIG. 9) so as to .bias the lid and base apart.
What I claim is: Y
l. A socket for an electrical plug and socket assembly comprising:
a first part having at least two spaced apart cavities for entry of terminals projecting from a package body;
a second part having at least two space@ apart openings in axial alignment with said cavities;
guide means between said first and second parts to permit movement between them in the axial direction of said cavities;
a resilient socket contact in each cavity extending between said first and second parts each having one end connected in a cavity at a point distal from the second part and the other end engaging the second part, the cavities being of a size to permit lateral movement of the contact so that upon movement of the first and second parts toward each other the resilient socket contact will flex;
said second part being normally biasedaway from the first part by said resilient contact means; and
said second part having an abutment surface between said openings for engagement with a package body so that when the package body and second part abut during the insertion of terminals into the cavities, further movement of the package body in the axial direction of the cavities wil cause the resilient contacts to flex and establish an electrical connection between the terminals and the resilient contacts.
2. A socket as claimed in claim 1, including retaining means for releasably holding the first and second parts in a first apart position and a second closed position in which the electrical connection is made between the terminals and the resilient contacts.
3. A socket for an electrical plug and socket assembly comprising:
a first part having at least one cavity for entry ofa terminal projecting from a package body;
a second part having an opening in axial alignment with said cavity; 7
guide means between said first and second parts to permit movement between them in the axial direction of said cavity;
a resilient socket contact extending between said first and second parts having one end connected in a cavity at a point distal from the second part and the other end engaging the second part, the cavity being of a size to permit lateral movement of the contact so that upon movement of the first and second parts toward each other the resilient socket contact will flex;
retaining means for releasably holding the first and second parts in a first apart position and in a second closed position in which the electrical connection is made between the terminal and the resilient contact;
said second part being normally biased away from the first part by said resilient contact means; said second part having an abutment surface for engagement with a package body so that when the I package body and second part abut during the insertion of the terminal into the cavity. further movement of the package body in the axial direction of the cavity will cause the resilient contact to flex and establish an electrical connection between the terminal and the resilient contact; and said second part has latch members which engage with notches in the first part to maintain the second part in either the first or second positions.
4. A socket as claimed in claim 3, in which the socket contact comprises two opposed portions arranged to approach each other during said further movement of the package body in the axial direction so as to engage opposite sides of the terminal contact.
5. A socket as claimed in claim 4, in which the opposed portions have opposed convex faces.
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