Title:
HINGE TYPE CIRCUIT BOARD CONNECTOR BLOCK
United States Patent 3701071


Abstract:
A connector block in which a daughter type circuit board is secured to a mother board by a hinge connection and then rotated about the hinge connection so that contact pads on the daughter board are brought into engagement with contacts on the mother board to form electrical connections therewith. Locking means are provided to hold the daughter board in the contact position relative to the mother board.



Inventors:
LANDMAN DIRK
Application Number:
05/107267
Publication Date:
10/24/1972
Filing Date:
01/18/1971
Assignee:
BERG ELECTRONICS INC.
Primary Class:
Other Classes:
16/225, 16/321, 16/DIG.13, 439/67, 439/71, 439/326, 439/329, 439/331, 439/357
International Classes:
H01R12/71; H01R12/83; H05K7/14; (IPC1-7): H01R13/54
Field of Search:
339/17,4,18,75,91,174-176 16
View Patent Images:
US Patent References:
3576518SOLDERLESS CONNECTOR FOR INSULATED WIRES1971-04-27Bazille, Jr. et al.
3327278Electrical interconnecting devices1967-06-20Godel
3184700Patchboard assembly1965-05-18Burke et al.
3158419Punch-card programmer1964-11-24Meyer et al.
3149896Electrical connector1964-09-22Hall
3054608Cantilever spring support bearing1962-09-18Para
2894241Right-angle printed wire connector1959-07-07McKee
2740097Electrical hinge connector for circuit boards1956-03-27Edelman et al.



Primary Examiner:
Mcglynn, Joseph H.
Claims:
What I claim as my invention is

1. A connector assembly comprising a base, a number of contacts on the base, support means adjacent said contacts for removably holding a circuit member, a hinge connection between said support means and said base whereby a circuit member held by said support means may be moved into engagement with said contacts by pivoting said support means relative to said base about said hinge connection, means biasing said support means for pivotal movement about the hinge connection away from said contacts, and means for limiting movement of the support means away from said contacts.

2. A connector assembly as in claim 1 wherein said hinge connection comprises a flexible metal part secured to both said support means and said base.

3. A connector assembly comprising a flat base member, a number of exposed contacts mounted on said base member, a unitary circuit member and means for forming a hinge connection between the circuit member and the base member including an opening formed through said base member with a portion of said circuit member extending freely into said opening and engaging one side thereof to permit free rotation of the circuit member relative to the base member for engagement with said contacts.

4. A connector assembly comprising a base member, a number of exposed contacts mounted on said base member, a daughter board, and means for forming a hinge connection between the daughter board and the base member whereby the daughter board may be moved into engagement with said contacts by pivotal movement about the hinge connection toward the contacts, said means comprising a slot in the base member for reception of one edge of the daughter board, said contacts including spring contact means for engaging printed circuit pads on the daughter board to form a wiped pressure connection therebetween, and latch means for holding the daughter board against said contacts.

5. A connector assembly comprising a socket for receiving and holding a circuit member, at least one hinge projection extending from said support, a base having a number of contacts projecting therefrom and at least one opening located adjacent said contacts for receiving said projection, said projection extending into said opening to form a hinge connection between said support and said base, said support being formed from sheet metal and said socket including a window therein for exposing part of the circuit member to said contacts.

6. A connector assembly of the type useful for forming electrical connections between a board and a circuit element comprising a base on the board, a support for the circuit element, a hinge connection between said base and said support, said base, hinge connection and support being formed of a single piece of plastic material with the hinge comprising a thin flexible portion of plastic material, a plurality of spring terminals mounted on the board and latch means for holding the circuit element in engagement with the terminals, said latch means comprising a flexible latch projection extending from said base and through openings in both said circuit element and said support to hold the circuit element in electrical connection with the spring terminals and to lock the circuit element within the socket and support.

7. A connector assembly comprising a base, a socket on one side of the base, a flexible hinge connection joining the socket to the base, a flat circuit member seated within the socket, a plurality of terminals on said side of the base having contacts adapted to make electrical connection with conductors in the circuit member seated in said socket, window means in one side of the socket exposing the circuit member to the terminals, latch means on the base, and a latching surface on the circuit member located outwardly of said socket and engagable with said latch means to hold the socket and circuit member therein adjacent the base for engagement between said conductors and terminals, said socket being rotatable away from said terminals about said hinge connection to permit insertion of a circuit member into the socket without engaging said terminals.

8. A connector assembly as in claim 7 wherein said socket and hinge connection are formed from an integral plastic member.

9. A connector assembly as in claim 7 wherein said latch means comprises a flexible latch extending away from said one side of said base, and including a hole formed through the thickness of said circuit member to receive said flexible latch, whereby upon rotation of the socket and circuit member toward the base the hole in the circuit member is moved over one end of the flexible latch and the flexible latch snaps back to engage the side of the circuit member away from the base.

10. A connector assembly as in claim 7 wherein said terminals include spring means biasing said circuit member away from said base.

Description:
The invention relates to a circuit board connector block useful in mounting a daughter type circuit board on a mother board or similar support. The block includes a base mounted on the mother board having a support for receiving a daughter board so that the daughter board is hinged to the base and may be pivoted to bring contact pads on the daughter board into electrical engagement with contacts, preferably of the spring type, on the mother board. The contacts may be in the base or in the mother board.

In conventional connector blocks used for mounting daughter board on a mother board or support, the edge of the daughter board is forced into a block so that it engages contact terminals and moves the same apart to form a spring biased electrical connection between the terminals and contact pads on the daughter board. A high insertion force is required in order to push the daughter board into the socket. Frequently during insertion the required high force results in breakage of the daughter board or injury of the components on the board.

Zero force type connector blocks, of the type disclosed in U.S. Pat. No. 3,526,869, have been proposed for reducing the force required to insert a daughter board into a connector block. In these blocks the terminals are spaced apart during insertion of the circuit board following which a cam member is actuated to either force the terminals into electrical engagement with the daughter board or release the same so that they spring against the daughter board contact pads. This type of block requires a large number of parts and is expensive to manufacture in terms of the cost of the parts and the labor required to assemble the parts. Further, after the daughter board has been inserted, it is necessary as a separate step to actuate the cam means to form the electrical connections. Frequently the electrical connections achieved by the conventional Zero Force type block do not include a wiping action between the terminal and circuit board pad to that it is possible that there is an undesirably high contact resistance between the terminal and the daughter board.

In the present invention, the daughter board is first inserted into a support so that it is hinged to the mother board and is then pivoted about the hinge connection to the closed position. During pivoting of the daughter board the contact pads engage spring contacts of terminals secured to the mother board. Further pivoting of the daughter board results in movement of the pads along the spring contacts to achieve a clean high pressure electrical connection when the daughter board is in the closed position. Snap latch means are provided to hold the board in the closed position. The support strengthens the board during pivoting and stressing of the spring contacts so as to prevent damage to the board resulting from the pressure exerted against it by the contacts.

A number of embodiments of the invention are disclosed herein according to which daughter board may be mounted in position either parallel or perpendicular to the mother board. In each case insertion of the daughter board into the support to hinge the daughter board to the mother board is accomplished without a high insertion force. After the daughter board has been inserted it is readily pivoted about the hinge connection to the closed position thereby forming the desired electrical connections with the terminals on the mother board. The invention may be used to form electrical connections between a given base or mother board and conventional daughter boards of the plainer circuit board type, tape cables, ceramic substrates and the like.

In contrast to the Zero Force blocks of the type where the terminal contacts engage the circuit board pads after insertion of the board into the block, the connector block according to the invention is easily and inexpensively manufactured of a reduced number of parts and does not require expensive manufacturing and assembly costs.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings illustrating the invention, of which there are seven sheets.

In the drawings:

FIG. 1 is a perspective view of the hinge type circuit board connector in the closed position;

FIG. 2 is a sectional view taken generally along line 2--2 of FIG. 1 but showing the connector in the open position;

FIG. 3 illustrates an alternative type of hinge for use in the connector of FIGS. 1 and 2;

FIG. 4 illustrates stressing of the spring contacts during closing of the connector;

FIG. 5 is a sectional view taken along line 5--5 of FIG. 2;

FIG. 6 illustrates a further embodiment of the invention in which a circuit board is held against two rows of contact members;

FIG. 7 is a sectional view taken along line 7--7 of FIG. 6;

FIG. 8 illustrates a further embodiment of the invention useful in forming electrical connections with conductors in a tape cable;

FIGS. 9 and 10 are sectional views taken along lines 9--9 and 10--10 of FIG. 8 respectively;

FIGS. 11 and 12 illustrate other embodiments of the invention;

FIGS. 13 and 14 illustrate an additional embodiment of the invention;

FIG. 15 is a perspective view of a part of the connector of FIGS. 13 and 14;

FIG. 16 illustrates another embodiment of the invention in the open position; and

FIG. 17 illustrates the embodiment of FIG. 16 in the closed position.

The hinge type circuit board connector of FIGS. 1 thru 5 comprises a plastic body 10 preferably formed by a molding operation having a base 12 mounted on circuit board 14 by screws 16 or other suitable means and a circuit board support 18 which is connected to the base 12 by an elongate flexible plastic hinge 20. The hinge permits rotational movement of the support 18 between the open position illustrated in FIG. 2 and the closed position of FIG. 1. Support 18 includes a stop 22 which engages the circuit board 14 when the support is rotated away from the closed position. During formation of the connector 10, the plastic is preferably stressed so as to bias the support toward the open position and hold stop 22 against circuit board 14.

Base 12 includes a row of terminal receiving cavities 24 into which are inserted metal spring terminals 26. The terminals 26 are confined in the cavities by detents 28. When the base 12 is mounted on board 14, terminal solder ends 30 extend through openings 32 in the circuit board so that solder connections 34 may be formed between terminals 26 and circuit board pads 36 which surround each circuit board hole 32 on the side away from base 12. Flat curved spring contact portions 38 of each terminal 26 extend above base 12 toward support 18 and, in the embodiment of FIGS. 1 thru 5 are curved toward the hinge connection 20.

Support 18 includes a body portion 40 which extends along hinge 20 and a pair of arms 42 which project away from the body 40. As shown in FIG. 1, body 40 is somewhat longer than base 12 so that the base is located between arms 42. This construction permits closing of the connector without the arms engaging the base.

Daughter board receiving slots 44 are formed in arms 42 and join slot 46 formed in the face of body 40 between the arms. A circuit board 48 of the daughter board type may be mounted in support 18 by inserting it into the slots 44 until the end of the board is seated within slot 46. The daughter board 48 is provided with a number of exposed printed circuit surfaces or pads 50 located at the end seated in slot 46 and spaced so that each contact surface 50 is located above the contact portion 38 of a terminal 26. The daughter board 48 is freely inserted into the support 18 as described when the support is in the open position of FIG. 2. Board 48 may carry a variety of electronic components and circuit elements which do not relate to the present invention and are not illustrated in the drawings.

A flexible latching member 52 is secured to the circuit board 14 a distance away from the connector 10 and is used to hold the daughter board 48 and support 18 in the closed position as illustrated in FIG. 1. A latch opening 54 is provided in the daughter board for engagement with snap latch 52.

After the daughter board 48 has been inserted in the circuit board support 18, the circuit board and support are pivoted toward board 40 about hinge 20 in the direction of arrow 56 shown in FIG. 2. As the daughter board and support are rotated toward board 14, the contacts 50 on board 48 are brought into engagement with terminal spring contacts 38. The first contact between the circuit board contacts 50 and terminal contacts 38 is shown in solid lines in FIG. 4, while the final contact point between the two is illustrated in dotted lines in FIG. 4. The initial contact between the terminal and the circuit board contact occurs at point 58. Further rotation of the circuit board about hinge 20 compresses the springs 38 and moves the point of contact between the circuit board contact and the spring from the original point of contact 58 to a final point of contact 60 which is located a distance from contact 58 closer to the axis of hinge 20. Thus, during the rotation of the daughter board 48 toward the closed position, the spring contact 38 is both compressed and wiped across a portion of the circuit board contact pad 50 to form a clean wiped high pressure electrical connection between the contact and the pad. The wiping action cleans both the contact areas on the pad and on the terminal contact. When the circuit board 48 and support 18 have been rotated to a position where the board is parallel to board 14, snap latch 52 is moved through hole 54 and snaps back to hold the circuit board and connection 10 in the closed position. In this position each terminal 26 is in electrical connection with a pad 50 on board 48.

If it should be desirable to replace daughter board 48 with a different board, for instance in the case of failure of a circuit component on board 48, the latch 52 is released and the assembly is pivoted to the open position where the daughter board 48 may be easily removed from support 18 and a new board may be inserted. Re-closing of the assembly wipes the terminal contacts 30 across the contact pads of the new board to assure that clean high pressure electrical connections are formed.

FIG. 3 illustrates a modification of the hinge type connector illustrated in FIG. 1 in that a flexible metal strip 64 is molded into base 12 and the support 18 to serve as a hinge in the place of the flexible plastic hinge 20. Movement of the support between the open and closed positions flexes the strip 64 at the junction 66 between the base and the support. The strip 64 is preferably formed of a relatively springy metal so it biases the support 18 toward the open position where stop 22 engages the mother board 14, as illustrated in FIG. 3. As illustrated in FIGS. 1 and 2, a snap latch 52 is used to hold the modification of FIG. 3 in the closed position. With the exception of the metal hinge member the modification of FIG. 3 is identical to the assembly illustrated in FIGS. 1 and 2.

FIG. 6 illustrates a different embodiment of the invention wherein a daughter board 70 may be mounted in electrical connection on circuit board 72 with individual connections formed at opposite edges of the daughter board. A pair of like insulating bases 74 are secured on board 72. Contact terminals 76 are secured in recesses 78 extending along bases 74 and include tail portions 80 which extend downwardly through openings 82 in the bases and holes 84 are formed in board 72 so that they project beneath the board. Solder connections 86 are formed between tails 80 and circuit board pads 88 on board 72. Terminal tangs 90 are bent into recesses 92 formed in base 74 in order to secure the terminals 76 to the bases. In order to meet the spacing requirements the tails 80 of adjacent terminals 76 may be staggered so that there are two rows of terminals tails in each base 74.

Each terminal 76 includes a curved contact spring 94 which prior to closing of the connector projects above the top of the base. Side walls 96 in recess 78 separate adjacent terminals. Each base 74 includes a hinge and locking ridge 98 extending along the outside of the assembly at the top of the base member. As illustrated in FIG. 7, a pair of flexible latches 100 project upwardly from the sides of the base members. Each latch member includes a projection 102 which extends toward the base member 74.

Stiffly flexible top 104 is provided with hook shape hinge latches 106 at opposite edges thereof which extend along the length of the base member 74. The top is also provided with locking recesses 108 formed in the adjacent latch members 100.

The circuit board 70 is secured in electrical connection with the terminals 76 by first placing the board on the top of the base member 74 so that it rests upon the exposed spring contacts in roughly the proper orientation. Then the top is placed in position by hooking one member 106 beneath the lip of one ridge 98 at one end of the assembly to form a hinge connection with the ridge 98 in the recess defined by hook 106 and then pivoting the top about such hinge connection toward the circuit board and base members until the other locking member 106 has been flexed past the other locking ridge 98 and snaps back into position, as illustrated in FIG. 6. At the same time the projections 102 on latches 100 snap into the locking recess 108 to assure that the top does not flex outwardly of the closed position and that the circuit board 70 is confined against movement away from the base members 74. It is also possible to lock the top in place by first positioning it above the base members while parallel to the circuit board 72 and then pushing it downwardly toward the board so that both the latching members 106 and latch fingers 100 snap into position at the same time.

As the top is moved to the position of FIG. 6, the circuit board is forced down against the spring contacts 94 of terminals 76 so that high pressure wiped electrical connections are formed therebetween. During the deflection of the contacts 94 from the rest position to the position of FIG. 6, the contact areas move a distance across the printed circuit contact pads 110 on the circuit board to assure that the connection between the terminals and the pads is clean of oxides and other impurities. The circuit board 70 may be replaced by flexing one snap latch free of the locking ridge 98 and moving the latching fingers 100 outwardly of the top to permit movement of the top away from the base members.

FIG. 8 illustrates a hinge type electrical connector assembly 120 useful for forming an electrical connection with a flexible tape cable 122 having a number of conductors 124 spaced along the width thereof. Assembly 120 utilizes a base member 126 identical to base member 74 of FIGS. 6 and 7 and having terminals 128 confined therein. The terminals 128 may be like terminals 76 in the previously described embodiment. Top 130 is similar to one edge portion of the top 104 in FIG. 6 and includes a latch member 132 which, in the closed position, is positioned behind ridge 134 of the base member 126. A groove 136 is formed in the top 130 to accommodate tape cable 122 so that when the top is in the closed position of FIG. 8, each of the conductors 124 in the cable is located above and in electrical connection with a terminal 128.

During assembly of the connector the tape cable is first inserted into the groove 136 and then the latching member 132 is hooked beneath ridge 134 to form a pivot type hinge connection between the base member 126 and the top 130. The top is then pivoted toward the base about the hinge connection so that the conductors in the cable are brought into electrical connection with the contact springs of terminals 128 and the latching fingers 138 snap into recesses 140 to confine the top to the base in the closed position. As in the previous embodiment, closing of the connector assembly forms a high pressure wiped electrical connection between the conductors in the tape cable and the individual terminals.

The assembly 120 may be opened by pulling the latching fingers away from the top to release it for pivotal movement away from the base member so that the tape cable 122 may be replaced if necessary.

FIG. 11 illustrates another embodiment of the invention useful for forming electrical connections with the conductors 141 of tape cable 142. The connector assembly includes a base 143 which is suitably mounted on mother board 144 and a tape cable support or top 145 secured to the base 143 by an elongate plastic hinge 146 similar to hinge 20 in FIG. 2. A plurality of terminals 147 are spaced along the length of base 143 and extend through the base and board 144 so that solder connections 148 may be formed with circuit board pads 149. The support 145 is provided with a tape cable receiving recess 151 whereby the end of tape cable 142 may be positioned within the support with each exposed conductor 141 thereof positioned above a terminal 147 in base 143. The recess mouth 153 is tapered somewhat to facilitate insertion of the tape cable within the recess.

After the tape cable has been positioned in the support as described with the support in the open position, illustrated in dotted lines in FIG. 11, the cable and support are pivoted about hinge 146 toward the closed position indicated in solid lines in FIG. 11. Closing of the assembly brings the terminal contacts 155 into engagement with the tape cable conductors 141 so that a wiped high pressure electrical connection is formed therebetween. Suitable latching means (not illustrated) such as latches 100 illustrated in FIGS. 6 and 9, are provided for holding the connector in the closed position. Teeth 157 which project upwardly from the walls 159 separating adjacent terminals 147 bite into the cable 142 to prevent cable pull-out.

FIG. 12 illustrates a hinge type connector assembly 150 similar to that of FIG. 1 including a base member 152 which is mounted on a circuit board 154. Suitable means indicated at 156 is used to secure the base member on the circuit board. While FIG. 12 illustrates the base member as being mounted on one edge of board 154, it is obvious that the base member may be mounted at any desired location on the circuit board and need not be mounted at one edge of the board.

The base member 152 extends for a distance along the circuit board and includes an upwardly projecting ridge 156 in which is formed an elongate circuit board receiving slot 158. The slot is slightly wider than the thickness of the daughter board used with the assembly. A number of terminals 160 are mounted in board 154 in a row or rows extending parallel to base member 152. In FIG. 12 two rows of terminals 160 are illustrated with the terminals in each row staggered to prevent engagement between adjacent terminals. The terminals project through circuit board holes 164 in the board and are soldered to circuit board pads 166 on the bottom of the board. The terminals include flat curved spring contacts 168 which project upwardly from board 154 and are curved toward the slot 158. The spring contacts 168 are shown in the unstressed position in dotted lines in FIG. 12.

Assembly 150 is used to mount a daughter board 170 on circuit board 154 in electrical connection with terminals 160. One end 172 of the daughter board is first positioned in circuit board receiving slot 158 with the board 170 oriented as shown in dotted lines in FIG. 12 so that the board angles away from board 154. Circuit board pads 174 on the bottom of the daughter board are positioned above the terminals 160. The daughter board is then pivoted about the upper surface of slot 158, which cooperates with the board to form a hinge connection so that the circuit board pads 174 are brought into engagement with the spring contacts 158, and with further pivotal movement of the board a wiped high pressure electrical connection is formed therebetween. A suitable flexible latch similar to latch 52 illustrated in FIGS. 1 and 2, may be used to hold the circuit board 170 in the contact position of FIG. 12 where it is parallel to board 154. The latch may be released in order to permit replacement of board 170 with a different circuit board.

While FIG. 12 illustrates a number of terminals 160 located adjacent the hinged connection between the board 170 and base member 152, it is obvious that terminals may be provided at any desired location in board 166 beneath board 170 and that a reliable electrical connection will be formed between such terminals and the daughter board 170 as it is moved to the closed position.

FIGS. 13 thru 15 illustrate a circuit board connector assembly 180 useful in forming electrical connections between circuit board 182 and daughter board 184. A number of electrical terminals 186 project above the surface of board 182 and include curved spring contacts 188 similar to the previously described spring contacts. The terminals 186 may be soldered to form electrical connections with printed circuitry 190 on the bottom of board 182. A pair of hinge openings 192 are formed in the circuit board 182 to one side of terminals 186.

FIG. 15 is a perspective view of a circuit board support 194 which may be formed from thin sheet metal stock or other suitable material such as plastic. The support includes a top 196 with side walls 198 on opposite sides thereof. Lips 200 extend inwardly from the free ends of walls 198 to define a daughter board receiving socket 202. The mouth 104 of socket 202 may be flared to facilitate insertion of the daughter board. Socket back 206 extends from the top 196 past walls 198 and includes one leg of L-shaped hinge tabs 208. The free legs of tabs 208 extend from back 206 in a direction away from the top 196.

As indicated in FIG. 13, daughter board 184 may be freely inserted into socket 202 so that the circuit pads 210 are located between the ends of flanges 200. The daughter board is inserted into the socket until the end 212 thereof abuts the back 206 of support 194.

With the daughter board inserted in support 194, tabs or legs 208 are moved into circuit board holes 192 to attain the position illustrated in FIG. 13. The daughter board is then pivoted in the direction of arrow 214 toward circuit board 182. The free ends of tabs 208 engage the lower surface of circuit board 182 to form a hinge connection so that the daughter board is pivoted about the connection as it is moved toward board 182. Movement of the daughter board toward the mother board brings circuit pads 210 into engagement with the spring contacts 188 of terminals 186 to form wiped high pressure electrical connections therebetween.

A suitable latching member 216, which is similar to latching member 52 in FIG. 1, extends through latching hole 218 in the daughter board to hold the daughter board in the closed position parallel to the mother board with electrical connections formed between the mother and daughter boards. Latch 216 may be released in order to open the assembly 180 to permit removal of daughter board 184 and the substitution of a new daughter board, if required.

FIGS. 16 and 17 illustrate a further embodiment of the invention in which a hinge type circuit assembly 230 is used to mount a daughter board 232 on mother board 234. Assembly 230 includes a plastic base 233 which may be mounted on board 234 by suitable means indicated at 236. A row of terminals 238 is mounted in the base 233 with each terminal extending through a hole in the circuit board 234 so that solder connections may be formed between the terminals and printed circuit pads 240 on the bottom of board 234. Each terminal includes a spring contact portion 242 which is similar to the spring used in the previously described embodiments of the invention. A flexible latching member 243 projects away from the base 233 between the circuit board 234 and the contact springs 242.

A daughter board support 244 is connected to base 233 at elongate plastic hinge 246 located at the top of the base. As an alternative to the plastic hinge connection, a hinge connection of the type illustrated in FIG. 3 may be used. The support 244 includes daughter board socket 247 adaptable to receive one end of the daughter board 232. An opening 248 facing spring contacts 242 is formed in the socket so that the printed circuit contact pads 250 on daughter board 232 are exposed opposite the spring contacts 242 when the daughter board is inserted in socket 247, as illustrated in FIG. 16. When the daughter board is properly inserted, latching hole 252 in the daughter board is in alignment with a latching opening 254 formed in support 244.

After the daughter board has been inserted as described, the board and support 244 are pivoted about hinge 246 in the direction of arrows 256 to bring the assembly to the position of FIG. 17. This pivotal movement brings each circuit pad 250 on board 232 so that the contacts 242 are deformed and a wiped high pressure electrical connection is formed between the terminals and the contact pads. When the daughter board is in the mounted position, it extends perpendicularly away from mother board 234. Movement of the daughter board and socket to this position forces the latch hole 252 and latch opening 254 past the latch on the end of latching member 243 to lock the board in the closed position. One or more latching members 243 may be provided in assembly 230 depending upon the width of the assembly and the number of terminals provided in the assembly. As the latching member 243 extends entirely through latching hole 252 in the daughter board, the daughter board is positively located in the assembly and accidental withdrawl is prevented.

In each embodiment of the invention closing of the assembly forms a wiped electrical connection between the pads on the daughter board and the terminals. This is assured because during stressing of the terminals the pad is pivoted about the axis of the hinge while the spring contact is not. Thus, the hinge connection between the daughter board and the base assures wiped connections.

While I have illustrated and described preferred embodiments of my invention, it is understood that these are capable of modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.