US3588785A

US3588785A - Connector assembly

Info

Publication number: US3588785A
Application number: US881792A
Authority: US
Inventors: Alfred T Hardardt; Edward C Uberbacher
Original assignee: International Business Machines Corp
Current assignee: International Business Machines Corp
Priority date: 1969-12-03
Filing date: 1969-12-03
Publication date: 1971-06-28
Anticipated expiration: 1988-06-28

Abstract

A HOUSING IS PROVIDED HAVING A PLURALITY OF THIN WALLS LOCATED ADJACENT AND PARALLEL TO ONE ANOTHER WITH EQUAL SMALL SPACINGS THEREBETWEEN. EACH SPACING BETWEEN THE WALLS DEFINES A RECEPTACLE HAVING AN UPPER AND LOWER SECTION SEPARATED BY A MIDDLE SECTION. THE MIDDLE SECTION HAS AN OPENING WHICH EXTENDS THROUGH THE HOUSING AND WHICH IS SUFFICIENTLY LARGE SO THAT AN END SECTION OF A DOUBLE-ENDED CONTACT MEMBER CAN PASS THERETHROUGH. THE DOUBLE-ENDED CONTACT MEMBER HAS A TUNING FORK-SHAPED END SECTION AT EACH END OF A MIDDLE SECTION. AFTER ONE END OF THE DOUBLE-ENDED CONTACT MEMBER IS PASSED THROUGH THE MIDDLE SECTION OPENING OF THE RECEPTACLE, THE CONTACT MEMBER IS PIVOTED SO THAT ONE TUNING FORK-SHAPED END FITS INTO THE UPPER SECTION OF THE RECEPTACLE AND THE OTHER TUNING FORK-SHAPED END FITS INTO THE LOWER SECTION OF THE RECEPTACLE. LOCKING MEANS ARE PROVIDED FOR HOLDING THE DOUBLE-ENDED CONTACT MEMBER LOOSELY IN POSITION WITHIN THE HOUSING SO THAT THE CONTACT MEMBER IS PIVOTALLY WITHIN PREDETERMINED LIMITS ESTABLISHED BY THE LOCKING MEANS.

Description

United States Patent [72] inventors Alfred T. Hardardt Wappingers Falls; Edward C. Uberbacher, Poughkeepsie, N.Y. [21] Appl. No. 881,792 [22] Filed Dec. 3,1969 [45] Patented June 28, 1971 73} Assignee International Business Machines Corporation Armonk, N.Y.

[54) CONNECTOR ASSEMBLY 10 Claims, 6 Drawing Flgs.

[$2] [1.8. CI 339/64, 339/156, 339/176, 339/217 [51] Int. Cl 110lr 13/08, HOlr 13/42, H051: 1/12 [50] Field 01 Search 339/17 (L,LC,LM),17(M),64,154,156,176,192, 204, 205, 217

[56] References Cited UNITED STATES PATENTS 2,872,659 2/1959 Wills 339/255 3,129,991 4/1964 Sehmitz 339/17 3,205,471 9/1965 Herrmann 339/176 OTHER REFERENCES R. L. Agard et al., Card To Card Connector, IBM TECH. DISC, Vol. 6N0. 3,Aug. l963,page 14. Copy in 339- 176(MP) Primary Examiner-Marvin A. Champion Assistant Examiner Lawrence J. Staab Attorneys-Hanifin and Jancin and Harold H. Sweeney, Jr.

ABSTRACT: A housing is provided having a plurality of thin walls located adjacent and parallel to one another with equal small spacings therebetween. Each spacing between the walls defines a receptacle having an upper and lower section separated by a middle section. The middle section has an opening which extends through the housing and which is sufficiently large so that an end section of a double-ended contact member can pass therethrough. The double-ended contact member has a tuning fork-shaped end section at each end of a middle section. After one end of the double-ended contact member is passed through the middle section opening of the receptacle, the contact member is pivoted so that one tuning fork-shaped end fits into the upper section of the receptacle and the other tuning fork-shaped end fits into the lower section of the receptacle. Locking means are provided for holding the double-ended contact member loosely in position within the housing so that the contact member is pivotally within predetermined limits established by the locking means.

Patented June 28, 1971 3,588,785

2 Sheets-Sheet 1 INVENTORS ALFRED T, HARDARDT EDWARD Cv UBERBACHER ATTORNEY Patented June 28, 1971 2 Shae cs-Sheet 2 CUNNECTOW ASSIEMMJY This invention relates to a connector assembly and more particularly, to a contact assembly for making electrical connections between pins on adjacent surfaces of parallel circuit boards.

As circuit manufacturing techniques improve, such as etching techniques for producing printed circuits on dielectric cards, the limitation in circuit density is caused by the limited space along the edge of the cards for making the large number of electrical circuit edge connections to other circuits in the system. This limitation has been overcome to some degree by the provision of a card surface to surface connection means. Generally, the surface to surface interconnecting means consists of pins extending from circuits on the boards. The pins serve as the male portion of an interconnecting means. n the adjacent board, a female contact member is soldered or connected to the circuit to which the male pin is to be connected. The female contact member is included in an interconnecting housing into which the male member is plugged. The interconnecting housing provides the stability for the pins and the female connector contact as well as rigidity so that the pins can be positioned with respect to the female contact.

Such an interconnecting assembly does not provide for any nonalignment of the pin and the female contact due, for example, to a misalignment of the circuit cards themselves. If one of the female contacts is discovered to be faulty and needs to be replaced, it is necessary to detach it from the circuit board. For example, by melting a solder joint. It has also been found that electrical crosstalk is introduced because of close spacing ofthe contacts of the connector assembly.

Accordingly, it is an object of the present invention to provide a contact assembly which not only provides the necessary stability and rigidity for the contacts but provides for making the interconnection when the contacts to be interconnected are displaced with respect to one another within predetermined limits.

It is another object of the present invention to provide a contact assembly in which the interconnecting contact is part of a separate assembly not requiring attachment to either circuit board to be interconnected.

It is a further object of the present invention to provide a contact assembly from which the contact can be easily removed for replacement.

It is a further object of the present invention to provide a contact assembly in which the contacts can be closely spaced and yet minimize crosstalk.

The contact assembly provides a means for making electrical connections between pins on adjacent surfaces of circuit boards which are located parallel to one another. A housing is provided having a plurality of thin walls located adjacent and parallel to one another with an equal small spacing therebetween. Each spacing between walls defines a receptaclc having an upper and lower section separated by a middle section. The middle of the receptacle comprises an opening extending through the housing of sufiicient size so that an end section of a double-ended contact member can pass therctlirough. The double-ended contact member has a tuning fork-shaped end section at each end of a middle section. The double-ended contact member, after having one end passed through the middle section opening of the receptacle, is pivoted so that the one tuning fork-shaped end fits into the upper section of the receptacle and the othertuning fork end fits into the lower section of the receptacle. The locking means is provided for loosely holding the double-ended contact member in position within the housing. Each doublecnded member has the end of each tine curved so that a pin displaced from the opening between the tines will strike the curved surface thereby exerting pressure on the contact member causing it to pivot within the play provided between the housing and the locking means allowing the pin to fit within the tines of the contact member.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings.

FIG. II is a schematic isometric view of the contact assembly showing the contact at various positions during the insertion thereofinto the housing.

FIG. 2 is a cross-sectional view taken along the line 2-2 of FIG. I showing the contact in position and connecting the pins of opposing circuit boards.

FIG. 2a is a schematic representation similar to FIG. 2 but showing the contact member pivoted to its limit because of misaligned circuit board pins.

FIG. 3 is a cross-sectional diagram of a housing showing the locking tabs at the edge ofthe opening in the middle section of the receptacle.

FIG. 4 is a further cross section diagram of the housing showing an alternate contact locking means.

FIG. 5 is a further cross-sectional diagram of the housing showing another locking means for loosely holding the contact in position.

Referring to FIG. I, there is shown a contact assembly 10 comprising a housing l2 having a number of closely spaced parallel walls l4 which define spaces therebetween forming separate receptacles 116. As can be seen best from FIG. 2, each of the receptacles 16 is formed of an upper section 18, a lower section 20 and a middle section 22. The upper section 10 has a solid filled portion 24 made of the housing dielectric material and extending halfway through the housing. The bottom edge 26 of the solid portion 24 forms the top wall of the opening 28 which extends through the middle section 22 of the receptacle 16. Similarly, the bottom section 20 ofthe receptacle 16 has a solid or filled portion 30 which is on the opposite side of the receptacle with respect to the solid portion 24 of the upper section 18 of the receptacle. The top edge 32 of the solid portion 30 of the bottom section 20 of the receptacle 16 forms the bottom wall of the opening 28 through the middle section 22 of the receptacle. Each of the

solid portions

24,30 has an

extension

34,36 at the lower and upper end thereof respectively, which extends into the adjacent

open portion

30,40 of the receptacle.

A contact member 42 is provided which has a tuning forkshaped

end section

44,46 at either end. The tuning forkshaped

end sections

44,46 are connected by a middle section 48 which lies in the same plane as the end sections but is arranged such that the end sections are offset in the same plane with respect to one another. The contact member 42 is made out of a spring material, such as phosphor bronze, so that the tines ofthe tuning fork ends 44,46 press against the pin 50 as it is forced therebetween thus giving a good wiping contact.

A locking means in the form of a locking tab 52 is shown located at the bottom of the U-shaped opening between the tines of the tuning fork-

shaped end sections

44,46. The locking tab 52 is a small protrusion extending from the wall 14 of the receptacle l6. It will be appreciated, that a locking tab 52 is located in each of the upper and

lower section openings

38,40 so as to provide the positioning of the contact member 42. The locking tabs 52 sit in the bottom of the larger U- shaped openings between the tines providing some play therebetween. Each contact member 42 has a

cutout

54,55 in the portion between each

end section

44,46 and the middle section 48. As can be seen from FIG. 2, the cutout portion 54 between the middle section 45 and the upper end section 44 is on one side of the contact member 42 and the cutout portion 55 between the lower end section 46 and the middle section 48 is on the opposite side. Thus, when the contact member 42 is in position within the housing 112 as shown in FIG. 2, the upper and lower

solid portion extensions

34,36 fit into the upper and

lower cutout portions

54,55, respectively. These

cutout portions

54,55 and

extensions

34,36 provide a positioning means which prevents the contact member 42 from dropping out ofeither end of the housing 12.

Referring to FIG. 11, it can be seen that the contact member 42 is inserted into the housing 12 by pushing the appropriate end section through the middle section opening 20 of the receptacle I6. Once the appropriate end section has passed through the middle section opening 20, the contact member 42 is pivoted upward until it is vertical and locks into the receptacle via the locking tabs 52. The locking tabs 52 have a much smaller radius than the curved bottom of the U-shaped opening between the tines of the tuning fork-shaped ends 44,46 of the contact member 42. Thus, the contact member 42 is not rigidly locked into the housing receptacle 16 but has a certain amount of play either way provided by the play between the U-shaped opening and the locking tab 52.

FIG. 2a shows the contact member 42 in position within the housing 12 with the contact member 42 pivoted to its limit with respect to the locking tabs 52. It will be appreciated that any displacement of the pins 50 on the adjacent boards to be connected can be tolerated if it lies within the pivoting limit of the contact member 42. Actually, the diameter of the pins 50 and the radius of the curved ends of the tines of the tuning fork-shaped contact ends are selected so that the pins 50 will be insertable into the contact member 42 as long as they are within the pin displacement tolerance established by the play between the locking tab 52 and the contact member 42.

Alternate receptacles 16 in the housing have a different arrangement of the

solid portions

24,30 with respect to the

open portions

38,40 in the upper and

lower sections

18,20. The alternate receptacles I6 have the

solid portion

24,30 on the opposite side of the receptacle 16. Therefore, the

open portions

38,40 on alternate receptacles are on opposite sides. The

open portions

38,40 of one receptacle I6 will be as shown in FIG. 2 while the alternate receptacle 16 will have the open portions reversed as seen in FIG. I. The contact member 42 will be inserted into the housing 12 from the right side, as shown in FIG. 1, where the opening portion 38 is on the right side of the upper section 18 of the receptacle 16. The contact member 42 will always be oriented as shown in FIG. I for insertion no matter which side it is entered from. That is, the

cutout portion

54,55 ofthe tuning fork-shaped end being inserted will always be facing downward. The contact member 42 for the alternate receptacle wall will be entered thru the opening portion 38 on the left side of the housing 12 with the same orientation and of course also pivoted upward to lock into position within the housing. It would appear from FIG. 2, that the contact member 42 cannot be inserted from the wrong side or upside down since the middle section 22 of the contact member will contact the outer edges of the

solid portion

24,30 of the housing 12 and thus will prevent the further insertion of the contact member. The contact members 42 when in position within the housing 12, will not have

end sections

44,46 of alternate contact members adjacent each other. This is due to the combination of the offset construction of the

end sections

44,46 of the contact member 42 with respect to each other and the opposite structure of alternate receptacles l6. Referring to FIG. 1, it can be seen that the corresponding ends of the alternate contact members 42 are not side by side but are staggered from one another. This staggered feature minimizes the crosstalk between contact members.

A contact member 42 is shown in position within the housing in FIG. 3. The contact member is supported by the

cutout portions

54,55 between the middle sections 48 and the

end sections

44,46 where they rest on the solid

portion extension members

34,36. The contact members 42 are restrained or held in the housing by upsets 58 which are located along the edges of the housing wall 14 and which extend into the opening 28 which runs through the middle section 22 of the housing 12. These upsets 58 are protrusions past which the contact member 42 can be forced but which are of sufficient height to prevent the contact member from falling out of the housing 12. It should be noted that the upsets 58, one on each edge wall 14 of the opening 28, are not located across from one another but are slightly offset. This is to accommodate the shape of the contact member 42. The upsets 58 are located a short distance from the contact member 42 and thus, the contact member 42 has considerable play between the

solid portions

24,30 and the upsets 58 so that the contact member 42 can pivot within predetermined limits determined by the

solid portions

24,30 and the upsets 58. Thus, pins 50 to be inserted at either end of the contact member 42 will, if not properly aligned, cause a contact member 42 to pivot so that the pin 50 can slide easily into the opening between the tines provided therefor. Of course, if the pins 50 are displaced from their desired position, more than the acceptable tolerance which is defined by the amount of pivot established between the

solid portions

24,30 and the upsets 58 of the receptacle, the pin 50 will not be able to enter the contact member opening.

A further embodiment of the holding or locking means for holding the contact member 42 within the housing 12 is shown in FIG. 4. The contact member 42 has slightly rounded

extensions

60,62 or protrusions extending downward and upwardly respectively, from the lower and

upper walls

64,66 of the upper and lower tuning fork ends 44,46. These

walls

64,66 are formed in the

cutout portions

54,55 between the middle portion 48 and

end portions

44,46 of the contact member 42, as previously described. The

extension members

34,36 extending from the

solid portions

24,30 of the upper and

lower sections

18,20 of the housing 12 each have a

small projection

68,70 extending at right angles thereto at the end thereof. These

projections

68,70 extend in the opposite direction, the upper projection 68 extending upward and the lower projection 70 extending downward when the housing 12 is in the vertical position as shown in FIG. 4. The

protrusions

60,62 on the contact member 42 lock behind these

projections

68,70 on the

extension members

34,36 when the contact member 42 is in position thereby holding the contact member 42 within the housing 12. Again, it will be appreciated, that these locking members do not rigidly hold the contact members 42 in a fixed position but fit together loosely so that there is some play between the locking members so that the contact member 42 can pivot to a certain degree. As previously mentioned, this pivoting is necessary to provide a displacement tolerance for the pins 50 which are to be connected via the contact member 42.

In FIG. 5, there is shown a further embodiment of the locking means for holding the contact member 42 loosely in position within the housing [2. This consists of a pair of notches 72,74 cut in the contact member 42. One notch 72 is cut in the side of the upper tuning fork end 44 which abuts the upper solid portion 24. Similarly, the other notch 74 is cut in the other side of the lower tuning fork end 46. Matching or near matching

protrusions

76,78 are provided on the walls of the

solid portions

24,30 opposite the notches 72,74. Thus, the

protrusions

76,78 snap into the notches 72,74 to hold the contact member 42 within the housing 12. As can be seen from FIG. 5, the notches 72,74 in the contact member 42 are slightly bigger than the

protrusions

76,78 so that there is some play between the two. This allows the necessary pivoting of the contact member 42 within the housing 12 to adapt to pins 50 on opposing cards which are displaced within the pivoting tolerance.

While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and detail may be made therein without departing from the spirit and scope of the invention.

We claim:

1. A contact assembly for making electrical connections between pins on adjacent surfaces of parallel circuit boards, comprising:

a housing having a plurality of thin walls located adjacent and parallel to one another with an equal small spacing therebetween, each spacing between walls defining a receptacle;

each receptacle having an upper and lower section separated by a middle section;

a double-ended contact member having a tuning forkshaped end section at each end;

a middle section interconnecting said tuning fork-shaped end sections, said middle section of each receptacle comprising an opening extending through the housing, said opening being dimensioned so that an end section of said double-ended contact member can pass therethrough;

said double-ended contact member after passing one end thereof through said middle section opening of said receptacle, is pivoted so that the one tuning fork-shaped end fits into the upper section of the receptacle and the other tuning fork end fits into the lower section of the receptacle;

locking means for holding said double-ended contact member loosely in position within the housing;

said double-ended contact member having the tines of said tuning fork-shaped ends curved so that a pin that is slightly out of position but within the acceptable displacement tolerance will exert pressure on said curved surface causing the double-ended tuning fork contact member to pivot thus allowing the pin to fit between the tines of said contact member.

2. A contact assembly according to claim 1, wherein said upper section of said receptacle has a solid portion on one side and an open portion on the other side, and said lower section is the reverse having the solid portion below the open portion of the upper section and having the open portion below the solid portion of the upper section, the lower edge of the solid portion of the upper section and the upper edge of the solid portion of the lower section forming the upper and lower walls of said opening in the middle section of said receptacle.

3. A contact assembly according to claim 1. wherein said double-ended tuning fork contact member has the end sections thereof offset from one another in the same plane.

4. A contact assembly according to claim 2. wherein said upper and lower section solid portions have a solid extension extending laterally from the bottom edge and top edge thereof into said upper and lower open portions, respectively.

5. A contact assembly according to claim 4, wherein said double-ended tuning fork contact member has a first and second inward cutout portion each extending inward from an opposite side of said contact member between the middle sec tion and the end section thereof, so that the solid extensions of said upper and lower solid sections fit into the respective cutout sections of said contact member thereby forming holding surfaces for said contact member.

6. A contact assembly according to claim 2, wherein the solid portions and the open portions of both the upper and lower sections of alternate receptacles are reversed whereby double-ended tuning fork contact members disposed in said alternate receptacles are alternately reversed thereby minimizing crosstalk therebetween.

7. A contact assembly according to claim 2, wherein said locking means comprises first and second raised bumps each on the wall of said receptacle, one in each of the upper and lower open portions of said receptacle, said bumps being located in and dimensioned within the open portions so as to fit loosely into the bottom of the cutout portion between the tines of the tuning fork-shaped ends of the contact member thereby holding the contact member in position.

8. A contact assembly according to claim I, wherein an upset is located on each edge of the opening in the middle section of the receptacle, said upsets being adjacent the middle section of said double-ended tuning fork contact member so as to provide stops to keep the contact member within the housing.

9. A contact assembly according to claim 5, wherein said solid portion extensions each have a further protrusion extending at right angles to said extension and extending into the associated side located open portion, said contact member having an oppositely extending small projection at the outer end of said undercut portion so that the extension on said contact member locks behind the further protrusion of said extension member of said solid portion maintaining said contact member in position.

10. A contact assembly according to claim 2, wherein each of said solid portions has a key extension extending from the sidewall of said solid portions into the adjacent side located open portion, said contact member having openings therein located opposite said key extensions so that said key extensions snap into said opening thereby maintaining said contact member in position with said receptacle.