US3312930A

US3312930A - Terminal pin assembly

Info

Publication number: US3312930A
Application number: US431555A
Authority: US
Inventors: Hatfield John Gross; Loose Winfield Warren
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1965-02-10
Filing date: 1965-02-10
Publication date: 1967-04-04
Anticipated expiration: 1984-04-04
Also published as: GB1083757A; DE1565960A1; NL6601632A

Description

April 1967 J. G. HATFIELD ETAL 3,312,930

TERMINAL PIN ASSEMBLY 2 Sheets-Sheet 1 Filed Feb. 10, 1965 INVENTORE Jul-m Gauss HATFIELD \A/INF'IELD WARREN Lo BY M/Cd, M \s/W April 1957 J. G. HATFlELD ETAL 3,312,930

TERMINAL PIN ASSEMBLY 2 Sheets-Sheet 2 Filed Feb. 10, 1965 INVENTORS 4mm G-Ress HIM-Fina \Jmnuo wmuum LooSE BYM W+ W United States Patent ()fitice 3,312,939 Patented Apr. 4, 1967 3,312,930 TERMINAL PIN ASSEMBLY John Gross Hatfield, Camp Hill, and Winfield Warren Loose, Reading, Pa., assignors to AMP Incorporated, Harrisburg, Pa.

Filed Feb. 10, 1965, Ser. No. 431,555 4 Claims. (Cl. 339-147) This invention relates to a terminal pin assembly of the type adapted to be inserted into a receptacle to eifect an electrical connection between normally open contacts.

A Wide variety of terminal pins have been developed over the years adapted for use in coordinate switches, pinboards and programming devices and the like. Typically such devices are comprised of spaced planes of contact arrays suitably aligned to be intersected by the conductive portions of the pin and interconnected thereby. The general requirements for terminal pins include the provision of low resistance, mechanical strength sufficient to permit repeated manual insertion and withdrawal, low cost and small size. There is on occasion'an additional specific need for the pin to be coaxial to accommodate circuit elements such as diodes, resistors and the like, effectively placed in the circuit upon insertion of the pin.

The prior art has come up with a number of terminal pin constructions. These vary from a simple structure including a solid cylindrical brass piece, having a plastic cap molded thereon, to more complicated diode carrying pins, wherein several conductive and insulating layers are coaxially bound together to form insulated paths axially separated and joined to the ends of a diode or like device. One problem experienced with prior art terminal pins is that the conductive member frequently breaks off at the point of juncture with the insulating shroud. Another problem is that after a number of insertions and withdrawals the shroud becomes loosened from the pin member and slips off axially. A difficulty with coaxial type terminal pins presently used for diodes and the like is that the end of the pin is prone to break or bend to ruin the piece against further use. i It is an object of the invention to provide a terminal pin assembly featuring an insulating shroud which is inserted rather than molded on the conductive contact member and which includes an engagement with the shroud resisting both axial separation and pin breakage.

It is a further object of the invention to provide a diode terminal pin assembly having a diode receptacle structure and shroud permitting disassembly for replacement of the diode and shroud.

It is a general object to provide a terminal pin which is structurally stronger and more durable than heretofore available.

The foregoing objects are attained in the present in vention through several embodiments which include a generally tubular metallic shell member having spring characteristics and latch means adapted to cooperate and be spring fitted within a relatively thin and elastic insulating shroud to engage the interior of the shroud at two relatively widely spaced points axially thereof. The metallic shell member is so formed as to be capable of being collapsed to permit removal of the shroud Without damage thereto. The shell member includes in one embodiment a depending contact portion formed into a tubular configuration to provide a rigid pin structure to prevent bending or breakage in use. This same advantage is carried in a diode terminal pin assembly through the use of a centrally disposed solid pin member having material characteristics adequate to support the pin in combination with a dielectric spacer sleeve and a tubular outer member which carries the latching and supporting portions mentioned for engagement with the insulating shroud. An alternative of this latter embodiment includes means whereby the diode may be snapped into springloaded receptacle for ease of replacement.

In the drawings:

FIGURE 1 is a longitudinal view in section of the terminal pin assembly of the invention in one embodiment;

FIGURE 2 is a perspective of the parts of the terminal of FIGURE 1, exploded;

FIGURE 3 is an end-on view of the shell and shroud of the assembly of FIGURE 1 in its pre-assembled state;

FIGURE 4 is a view of the parts of FIGURE 3 as assembled;

FIGURE 5 is a longitudinal view in section of an alternative embodiment of the pin assembly of the invention;

FIGURE 6 is a perspective of the parts of the device of FIGURE 5 shown in an exploded relationship;

FIGURE 7 is a perspective, partially sectioned, showing a further alternative embodiment of the pin assembly of the invention; and

FIGURE 8 is an end-on view showing the center and inner spring portion of the assembly of FIGURE 7.

Referring now to FIGURE 1, there is shown a terminal pin assembly 10, which is comprised of two pieces, a contact pin member 12 and an insulating shroud 14. The assembly 10 is adapted to be employed to interconnect coordinate connectors such as pinboards of the type shown in US. application S.N. 198,839, filed May 31, 1962, now Patent No. 3,175,179 in the name of Robert G. Trump. In use with a pinboard or like device the assembly is gripped by the shroud 14 and guided so that the member 12 is inserted within a board aperture to engage two spaced sets of spring contacts and present an electrically conductive path therebetween. As heretofore mentioned it is important that the shroud not become axially displaced from the contact portion and it is important that the contact member 12 be sufficiently rigid as to avoid being bent. The device 10 is adapted to accomplish both of these objectives and to additionally permit the shroud 14 to be removed and replaced with a shroud of a different color or configuration for purposes of identification.

The contact member 12 includes a generally cylindrical or tubular formed sleeve 12a, rounded as at 12!) to prevent damage to complementary board contacts upon insertion of the member therein. The sleeve 12a is of a length to adequately engage both sets of spaced spring contacts and as contemplated it can be either considerably shorter or considerably longer than the embodiment shown, depending upon the complementary contact spacing. The member 12a is preferably made of brass stock material of a thickness suitable for rolling into the configuration shown with the seam being closed along the length thereof to provide the structural integrity of a closed tubular configuration.

At the end opposite to 12]) and integrally formed with 12a is a flared out tubular portion tapered as at 12c and generally circular as at 12d. Disposed around the periphery of 12d are a plurality of projections 12e forming an abrupt face directed toward the contact terminal portion 12a. The portion 12d is left with an open seam as indicated in FIGURES 2 and 3, which extends down through 120 and out for a short distance on 1211 for purposes to be hereinafter described. Integral with portion 12d and extending along the bottom thereof is an arcuate section 12g ended in the portion 12h which is turned up from the surface of 12g. The arcuate disposition of 12g strengthens this member against transverse bending moments to rigidly secure portion 12g relative to portions 12d.

The shroud 14 includes a main body portion 14a hollow along its length and having at one end a cap 14b shaped to facilitate insertion and withdrawal of the assembly 10. At the other end is an opening formed of a relatively thin walled segment 14c. From FIGURE 1 it will be apparent that the width dimension of 1211 and the disposition of 12g in conjunction with the general diameter of 12a cooperate to cause 12 to engage the inner surface of 14 at at least two spaced points. Because of this and the rigidity of 12g, the shroud M is prevented from being cocked or otherwise displaced relative to 12. The length of 12d is made such as to provide a substantial bearing area with the inner surface of 140 at the point of entry to resist breakage at the point of greatest stress. The relaxed diameter of 12d relative to the relaxed diameter of 14c is as is indicated in FIGURE 3 such as to be loaded under elastic pressure when 12 is inserted in 14. The space or gap left, as indicated in FIGURE 3, between the ends of 12d and 12 permit this structure to be collapsed under spring force when inserted within 140 to the closed configuration shown in FIGURE 4. An annular recess shown as 14d is provided, as indicated in FIGURE 1, in the sleeve portion 14c to engage projections 12!; of 12 and lock the shroud thereto. The shroud is made so that it is expanded silghtly by the insertion of 12d within 14c, and as mentioned 12d is compressed by such engagement.

The assembly thus includes a relatively rigid tubular structure in 12a integrally joined with a relatively rigid mounting portion including 12d, 12g, and 12h engaging longitudinally the interior of the shroud 1.4 at two relatively widely spaced points. The assembly additionally includes barbs or projections 12c held outwardly by the spring force of 12d into a recess of 14a, which is itself under pressure of 140 expanded by the insertion. To replace the shroud it is only necessary to force the portion 12d inwardly to disengage the projections 12c from the iner recess 14a without destroying the shroud.

Referring now to the embodiment of FIGURE 5, a diode terminal pin assembly is shown to include a forward contact pin member 22 having a central shaft solidly formed 22a terminated in an enlarged and rounded head 22b at one end. On the other end is a receptacle portion 220. In the center of 22 is an enlarged and rounded portion 22d which serves to lock 22 to 28, an insulating sleeve surounding the rear portion thereof.

Spaced from the head 22b is a sleeve member 24 having a tubular part 24a extending forwardly and portions 24c- 24f substantially identical to 120-121 of the embodiment heretofore described. End 2411 of 24 includes a split or bifurcated portion 24g adapted to receive one lead of a component 26, the other lead being inserted within the portion 220 of the member 22.

The shroud is substantially identical to the shroud 14 heretofore described. In use the embodiment of FF- URES 5 and 6 may be manufactured and sol-d assembled as in FIGURE 5, or in kit form with a customer supplying his own diodes or other components and performing the assembly indicated with the component leads being soldered into the receptacles formed by 220 and by 24g.

In the alternative embodiment of FIGURES 7 and 8, a terminal pin assembly is provided to facilitate component replacement. With respect to its forward pin member 42 and a rear sleeve portion 44 the assembly is substantially like that heretofore described. The shroud 5i? also is similar to that heretofore described. The structural distinction lies in the provision at one end of sleeve 44 of bifurcated spring members 4411 and at one end of 42 spring members shown enlarged in FIGURE 8, as 42c. With this embodiment various use of the pin in circuit may be accommodated by removing the shroud 5i and replacing the component by snapping the leads thereof into place between the two contact springs of the assembly.

In a preferred embodiment in accordance with FIG- URE l the forward pin member 12 was formed of brass stock stamped and rolled in the configuration shown and overplated with a standard nickel, gold plating. The shroud 14 was formed of nylon molded as indicated. In the embodiment in accordance with FIGURES 58 the

pin members

22 and 42 were formed of hardened brass screw machined to the shape shown and the

sleeves

24 and 44 were formed of brass stock suitably blanked and rolled to the configuration shown. The insulating sleeves 28 and 4-8 were formed of nylon, machined to the configuration shown, and the shrouds were nylon molded to the configuration shown.

The foregoing description is intended to point out preferred modes of practicing the invention which is defined by the following claims.

What is claimed is:

1. A terminal pin assembly of the type adapted to house a component and to provide a connection to input and output leads thereof including a first contact portion of a tubular configuration joined by a portion of enlarged diameter having spring characteristics in a radial sense and carrying a plurality of barbs, an arm member joining said further portion and extending axially relative to said first contact portion for a length substantial as compared to said first contact portion, said arm ending in a bifurcated flange disposed at right angles to the longitudinal axis of said assembly, a further contact member extending axially out from said first mentioned contact portion and of approximately the same diameter of said first contact portion in its forward part, the said further contact member including a central beam extending within said first contact portion and terminated in a receptacle adapted to accommodate one end of a component lead, the other end fitting in said flange, an insulating spacer surrounding said beam along its length and extending between said beam and said first mentioned contact portion to support and insulate said beam relative thereto, an insulating shroud having a bore of a length adapted to fit over said component and said arm to elastically engage the outer surface of said further portion and to engage said flange.

2. The assembly of claim 1 wherein the inner end of said beam includes a pair of spring finger members and the said bifurcated flange forms a plurality of spring finger members whereby a component may be mechanically and electrically inserted and withdrawn from said assembly.

3. In a terminal pin assembly the combination comprising a first metallic member having a forward generally cylindrical contact portion and having at the other end a further portion extending at right angles to the longitudinal axis of said contact portion, the said further portion being rigidly secured to said contact portion by an arm of substantial length compared to the length of said contact portion, an intermediate portion having a generally rounded configuration secured to said arm and contact portion, said intermediate portion including an axial slot to permit compression thereof to develop a spring action in a radial sense and including a plurality of barbs projecting outwardly beyond the major surface thereof, an insulating shroud of a length to be fitted over said arm and said intermediate portion, said shroud including an inner bore adapted to engage the said further portion and an outer bore slightly smaller in diameter than said intermediate portion such that when said shroud is positioned on said arm and intermediate portion said intermediate portion is compressed to develop an elastic reserve holding said barbs in engagement with the interior of said outer bore to lock said shroud to said metallic member and further including a second contact member having further contact portion forwardly of said first mentioned contact portion, said second contact member having a rod portion extending coaxially through said first mentioned contact portion and within said intermediate portion and there is further included an insulating sleeve surrounding said rod portion and supporting such within the said first mentioned contact portion, the inner end of said rod being relieved to accommodate a component lead, the said further portion being bifurcated to accommodate the other lead of a component.

4. The assembly of claim 3 wherein the inner end of said rod includes spring members and the said further portion includes spring members whereby a component may be snapped in or withdrawn from said assembly.

References Cited by the Examiner UNITED STATES PATENTS EDWARD C. ALLEN, Primary Examiner.

W. DONALD MILLER, Assistant Examiner.