US 3546663 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
- Dec. 8, 1970 w. H L G, JR 3,546,663
CONNECTOR ASSEMBLY AND TOOL Filed Dec. 19, 1968 2 Sheets-Sheet 1 2 v INVENTOR.
Dav/sflox/efafihful/ 8 Hapgood AI/omeys Gen/re W. Ho/mberg, Jr.
Dec. 8, 1970 c. w. HOLMBERG, JR 3,546,663
CONNECTOR ASSEMBLY AND TOOL Filed Dec 19, 1968 2 Sheets-Sheet 2 INVENTOR. Gen/re WHo/mberg, Jr.
By Daw'gHox/efafihfu/lfiHapgood Affomeys.
United States Patent 3,546,663 CONNECTOR ASSEMBLY AND TOOL Centre William Holmberg, Jr., Melville Park Road, Melville, N.Y. 11746 Filed Dec. 19, 1968, Ser. No. 785,081 Int. Cl. H0lr 11/22, /12
US. Cl. 339223 11 Claims ABSTRACT OF THE DISCLOSURE An electrical connector assembly for use with panel boards comprises a post member afiixed to the board The present invention is concerned with an electrical connector assembly for use in high density wiring of complex circuitry such as is found in computer circuits. The instant connector assembly comprises a metal contact member associated with a wire lead and a post member associated with a panel board. Connector assemblies presently in use for this purpose are positioned in grid patterns with separations in the order of one tenth of an inch for a wiring density of approximately one hundred connectors per square inch.
When it is necessary to alter the connections in such a grid of connector assemblies it becomes apparent that disconnection and reconnection of a single wire lead without disturbance of adjacent connections is extremely difficult. Additionally, such connector assemblies must remain firmly connected and not pull apart when the wiring is stressed, yet must be readily disconnectable when a change in wiring is desired. If several connector assemblies are disconnected accidentally, as often occurs with present day assemblies, it is extremely difircult to reconnect the assemblies in their proper location because the correct mating relationships between contact members is not apparent. There is a large number of connector assemblies mounted closely together and if two or more are accidentally separately it is very diflicult and time consuming to figure out the proper mating of elements.
The requirements for a combination of secure fastening and individual removability and reconnectability have not been met well by the connector assemblies presently available. Together with other problem areas these re-. quirements have forced a limit of wiring density upon the manufacturers of computer hardware. Higher wiring density and the capability of locking the contact members together while being able to separate them and reconnect them are desirable goals since these limitations are an important barrier to miniaturization.
The connector assembly of the present invention provides an extremely secure connection which can be separated and reconnected with ease without disturbance of adjacent connectors. Its locking strength approaches the tensile strength of either the wire to which it is attached or the connector members themselves. A removal and insertion tool cooperates with the contact member of the connector to aid in placement and repositioning of individual connector members.
In the drawings:
FIG. 1 is a perspective view of the connector assembly including the female contact member;
FIG. 2 is a perspective view of the female contact member and a portion of the post member in an assembled condition;
FIG. 3 is a view in elevation of the female contact member;
FIG. 4 is a plan view of the female contact member;
FIG. 5 shows the post member;
FIG. 6 is an end view of the female contact member;
FIG. 7 is an enlarged perspective view of a portion of a tool for use with the connector;
FIG. 8 is an overall perspective view of the tool of FIG. 7;
FIG. 9 is a view in elevation of the female contact member formed in accordance with a second embodiment of this invention; and
FIG. 10 is a plan view of the female contact member of FIG. 9.
Referring to the drawings, FIGS. l-6 show the female contact member 1 and post member 2 which comprise the connector assembly. In the normal application of such devices, the female contact members 1 are carried by insulated wires 12 and the post members 2 are af fixed to a panel board in a closely spaced grid pattern.
Connection is established by sliding the female contact member 1 over the post member 2 until locking tabs 3 and 4 snap into shouldered notches near the leading end 32 of the post member. The notches are formed with the end nearest the leading end of the post member having shoulders 30 and 31 forming abutment surfaces perpendicular to the axis 33 of the post member 2. Locking tabs 3 and 4 are carried by spring leaves 5 and 6 which urge the locking tabs inwardly. The secure lock afforded by the tabs and the abrupt shoulders 30 and 31 of the post member notches is to be distinguished from a mere spring detent which is easily dislodged. Heretofore, connector assemblies intended for use in the present environment have employed spring detents to provide retention force and to permit disassembly. The firm engagement of the locking tabs and abrupt shoulders of the connector of the present invention prohibits disassembly without deliberate displacement of the locking tabs from the shouldered notches of the post member. A removed contact member 1 can be mounted on the same post member or other post members.
The leading end of the female contact member 1 is formed into a guiding sleeve 7 into which the leading end portion 32 of the post member 2 is inserted. That leading end portion 32 is rounded in shape to aid in the insertion. A second guiding sleeve member 8 coaxial with guiding sleeve member 7 is located remote from the leading end of female contact member 1 to receive the leading end 32 of post member 2 when the post and contact members are assembled. Each of sleeves 7 and 8 is dimensioned to provide slight clearance about the post member 2. This slight clearance permits assembly of the contact member and post member without scratching the adjacent surfaces. Thus, electrical contact enhancing platings, such as gold provided on the surfaces of the post and female contact members, will not be injured or marred and will remain intact for their electrical contact purposes.
A rounded inwardly directed protrusion or dimple 9 is provided on the base 15 of the female contact member 1 in the path of post member 2 to cause slight deflection or bowing of the female contact or post members to force the post member to bear firmly against the upper and inner surfaces of the guide sleeves 7 and 8 thereby establishing a firm mechanical and electrical contact. The dimple 9 bears against the lower surface of post member 2 and provides the primary electrical contact. Dimple 9 is located nearer sleeve 8 to postpone deflection or preserve alignment of the post and sleeves until the leading end 32 of post 2 is adjacent to sleeve 8. The specific location of the dimple 9 is determined by the spacing between the sleeves 7 and 8, the rigidity of the female contact and post members and the height of the dimple. The notable feature of the location of dimple 9 is that the coaxial alignment of the post member and female contact member is preserved to prevent the post member from colliding with the edge of guiding sleeve 8. Placement of the dimple equidistant from each of the sleeves increases the probability of such a collision. Placement according to the present invention reduces that probability.
As can be seen in FIG. 2, post member 2 is received within sleeves 7 and 8. When the elements are properly positioned, locking tabs 3 and 4 engage the shoulders 30 and 31 of the notches in post 2. The tab-notch relationship is for locking purposes only; it is not to provide electrical contact although there will be some electrical contact. Locking tabs 3 and 4 are so shaped as to provide projecting portions or ears 18, 19 which extend transversely of the post member 2. These projecting portions or ears protrude to allow the locking tabs 3 and 4 to be spread apart by an appropriate tool to permit the female contact member 1 to be withdrawn from the post member 2 when removal is desired. A tool appropriate for this and other purposes is described below.
The wire 12 is affixed to female member 1 by conventional crimping or soldering means, such as conductor crimp sleeve 13 and a strain relief sleeve 14 which grips the wire insulation, in automatic machinery or by hand. A shrinkable tubular plastic sleeve (not shown) may be shrunk about the crimp to provide strain relief. In order to provide for increased wiring density, the wire connecting end may be rotated about an axis through the post so that the crimped portion lies along a diagonal with respect to connector assembly alignments on a panel board.
It is apparent that while the female contact member cannot be retracted from the post by virtue of the lock established between locking tabs 3 and 4 and the shouldered notches 30 and 31, there is little to prevent its being moved too far down the post during assembly. A gentle tug on the wire 12 associated with the female contact member will properly position it with respect to the post so that the locking tabs will snap into the post notches 30 and 31. If, however, the female contact member is pushed too far down the post, shouldered notches 30 and 31 will pass completely through sleeve 8 and will tend to catch on the back edge of sleeve 8 when the wire is pulled to position the contact member. If this occurs, the female contact member will remain incorrectly positioned on the post. To prevent such catching of notches 30 and 31 in such an event, outwardly curved guide tabs 10 and 11 are provided on the rearmost edge of sleeve 8 to serve as deflecting surfaces for realigning the post 2 with the sleeves and for guiding the shoulders 30 and 31 of post member 2 back through sleeve 8 toward lock tabs 3 and 4.
FIGS. 7 and 8 show an insertion and removal tool in a preferred form, similar to tweezers, formed from flat strip material. The upper leg 41 of the tool 40 is provided with a shaped end portion comprising a lug member 48 which is connected to the leg 41 by a narrow neck 43 and a tapered transition section 44. The opposing leg 42 is provided with a channel shaped grip 49 on its end. The tool may be made of insulating material.
When removal of a female contact member from a post is desired, the tool is slipped into place adjacent the protruding ears 18, 19 of the locking tabs 3, 4. The tool is guided to its proper position by the channel shaped grip 49 in which the lower surface of the female contact slides. By squeezing the tool in tweezer fashion, the narrow neck of shank portion 43 is placed between the protruding ears of locking tabs 3 and 4. The tool then is pulled away from the post. The locking tab ears slide along shank portion 43 and then along tapered section 44. As the locking tab ears slide along tapered section 44, they are spread apart to disengage the locking tabs from the shoulders 30 and 31 of the notches in the post member 2. When the tool slides far enough to allow the tabs to abut stop surfaces 45 of lug 48, the female contact member will be caught and withdrawn from the post by continued movement of the tool and is retained on the tool by the tweezer grip of the opposing legs 41 and 42. As can be seen, one continuous movement of the tool spreads the locking tabs to free the contact member and removes the contact member without harm.
For installation or for reinsertion of a removed female contact member, the contact member is positioned on the tool with the ears of the locking tabs 3 and 4 and either side of the shank portion 43 and the contact member held in position by the tweezer action afforded by the opposing leg 42. The contact member guide sleeve 7 is positioned over the leading end 32 of the post member and the tool is pushed inwardly toward the post. The ears of locking tabs 3 and 4 are intercepted by shoulder surfaces 46 and 47 to allow the tool to push the female contact member along the post to its proper position in which locking tabs 3 and 4 engage the notches 30 and 31 of the post member for secure attachment. Thus, the above described tweezer tool is capable of selectively disconnecting, repositioning and reconnecting a female contact member without disturbance of adjacent connections. A somewhat less convenient but nevertheless useful version of this tool eliminates the opposing leg 42. This lat ter version comprises only a single element substantially identical to the leg 41 of the tweezer version above described.
Although there has been shown and described a female contact member having the guiding sleeves, locking tabs and contact surfaces in series relationship with the wire crimping means, it is apparent that the wire can be associated wth the female contact member in other ways. For example, as may be seen in FIG. 9, the wire can be positioned so as to lie parallel to the axis of the contact member 1 but on the opposite side of the base 15 from that side having the guiding sleeves 7, 8 and locking tabs 3, 4 or, in other words, on the outer surface of the base. Such an arrangement preferably establishes contact with the conductor 50 of the insulated wire 52 in a crimp sleeve 54 near the leading end of the female contact member 1, and provides a strain relief sleeve 56 at the opposite end for crimping about the insulated portion or sleeve 58 of the Wire 52.
The primary purpose of this design is to provide a stronger bond between the wire 52 and the contact 1. In previous designs, such as the one illustrated in FIG. 3 it is common for the insulating sleeve 58 to slide relative to the conductor 50. Since the strain relief sleeve 14 grips a small portion of the insulating sleeve 58 and the insulating sleeve ends adjacent the end of the strain relief sleeve, experience has been that the insulating sleeve can slide through the strain relief sleeve leaving only the conductor crimp means 13 to attach the contact 1 to the wire. The present design provides a greatly elongated portion of the sleeve 58 between the strain relief sleeve 56 and the conductor crimp sleeve 54. The increased insulating sleeve length prevents the sleeve from pulling through since the sleeve will bunch-up as it slides relative to the conductor 59 and prevent complete withdrawal of the sleeve. Furthermore such an arrangement reduces the overall length of the female contact member and is advantageous in preventing inadvertent short circuiting between female GQ tflGl members such as may occur in the preferred embodiment when the axially aligned crimp means are accidentally bent.
1. A slidable disengageable electrical connector assembly for use with panel boards comprising an elongated post member adapted for mounting on the board and a resilient female contact member adapted for association with a wire, said post member having a locking tab engagement notch near its tip, said female contact member having first and second spaced guiding sleeves for slidably receiving the post member, a base between said guiding sleeves, an inwardly directed protrusion on the inner surface of said base intermediate said guiding sleeves to urge the post member against an inner surface of the guiding sleeves to cause relative bowing between said female contact and said post and establish electrical contact, and at least one locking tab spring biased toward the post member and engageable with the post member locking tab engagement notch to thereby lock the female contact member on the post.
2. The assembly of claim 1 wherein the engagement notch is formed with a shoulder on the end of the notch nearer the tip, the shoulder having an abutment surface substantially perpendicular to the axis of the post member.
3. The assembly of claim 1 wherein the post member has a pair of notches on opposite sides thereof and wherein the female contact member has a pair of spring biased locking tab members each having a projecting ear adapted for engagement with a tool to permit the locking tab members to be spread apart to disengage them from the notches on the post member to allow the female contact member to be withdrawn from the post member.
4. The assembly of claim 3 including first and second means on the outer surface of said base adapted to be fixedly attached to an electrical conductor and an insulating sleeve about the conductor, respectively, said first means being adjacent said first guiding sleeve and said second means being adjacent said second guiding sleeve.
5. The assembly of claim 4 wherein said first and sec- 0nd means are crimp sleeves.
6. The assembly of claim 3 wherein the inwardly directed protrusion is located nearer the second guiding sleeve which last receives the post member, whereby coaxial alignment of the post member with the female contact member is preserved until just prior to receipt of the post member by said second guiding sleeve.
7. The assembly of claim 3 wherein the second guiding sleeve which last receives the post member includes on the edge of that sleeve remote from the entry of the post member deflecting surfaces to prevent the locking tab engagement notches of the post member from catching on said edge during relative sliding movement of the female contact member and the post member.
8. A female contact member for assembly with an elongated post member to establish therewith an electrical connection, said post member having shouldered locking tab engagement notches near its tip, said female contact member having a pair of spaced guiding sleeves for slidably receiving the post member and having a pair of locking tab members spring biased toward the post member and engageable with the post member locking tab engagement notches to thereby lock the female contact member to the post member, each of the locking tab members having a projecting ear extending outwardly of the surface of the post member, and adapted for engagement with a tool for spreading apart said tab members in order to permit removal of the female contact member from the post member.
9. The contact member of claim 8 including first and second means on the outer surface of said base adapted to be fixedly attached to an electrical conductor and an ininsulating sleeve about the conductor, respectively, said first means being adjacent said first guiding sleeve and said second means being adjacent said second guiding sleeve.
10. The contact member of claim 8 wherein the contact has an inwardly directed protrusion, the protrusion being located nearer the second guiding sleeve which last receives the post member, whereby coaxial alignment of the post member with the female contact member is preserved until just prior to receipt of the post member by said second guiding sleeve.
11. The contact of claim 8 wherein the second guiding sleeve which last receives the post member includes on the edge of that sleeve remote from the entry of the post member deflecting surfaces to prevent the locking tab engagement notches of the post member from catching on said edge during relative sliding movement of the female contact member and the post member.
References Cited UNITED STATES PATENTS 2,731,617 1/1956 Doane 339256 2,962,693 11/1960 Ott 339258(S) 3,163,484 12/1964 Herman et a1. 339258(S) 3,262,087 7/1966 Mancini 339256 3,362,008 1/1968 Berg 339258 FOREIGN PATENTS 216,549 8/1958 Australia 339258(S) 385,314 3/1965 Switzerland 339258(S) MARVIN A. CHAMPION, Primary Examiner R, A. HAFER, Assistant Examiner US. Cl. X.R. 339-256