US3541496A - Terminal - Google Patents

Description

N 7, 1970 E. J; CASTELLANI 3,

' TERMINAL Filed on. 21, 1967 -FIG.114" I FIG.2

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ATTORNEY EDWARD J. CASTELLANI United States Patent 3,541,496 TERMINAL Edward J. Castellani, South Plainfield, N.J., assignor to Thomas & Betts Corporation, Elizabeth, N.J., a corporation of New Jersey Filed Dec. 21, 1967, Ser. No. 692,507 Int. Cl. H01r 9/16 U.S. Cl. 339-220 4 Claims ABSTRACT OF THE DISCLOSURE The invention is directed to a feed through contact pin and more particularly to a contact pin adapted to be staked to a terminal board or other supporting surface.

The pin is provided with a first contact portion having a shoulder coupled thereto. The shoulder is brought into contact with a first surface of the supporting member. A deformable staking portion coupled to the shoulder, and further coupled to a second contact portion which extends beyond the other surface of the supporting member, is positioned in an aperture in the supporting member. The first contact portion is then placed in a first portion of a staking die set having a nest shaped the same as that of the first contact portion and of the shoulder. The second portion of the die set is then positioned over the second contact portion, said second portion having a shape similar to the second contact portion as well as providing for the desired shape of a shoulder to be formed from the deformable staking portion. The die set is then closed by press means against the deformable staking portion, which staking portion is then deformed to form a shoulder on the opposite side of the supporting member from that provided by the shoulder of the first contact portion. Thus an intimate and positive connection between the supporting member and the contact pin is established.

BACKGROUND OF THE INVENTION Field of the invention The invention is generally directed to the field of contact blocks to provide for the interconnection of various electrical components. The invention is equally suited to connection to conductors whether by soldering, wire wrapping or similar techniques or may be employed with detachable contact pins or terminals.

DESCRIPTION OF THE PRIOR ART Contact pins, as are commonly found in the prior art, and which will provide contact surfaces on both sides of a supporting member, are of three general types. The first type is the so called snap-in type which provides two contact portions and a portion of a shank of decreased diameter which must be snapped into place in an aperture within a supporting member. Such snap-in contact pins require that the supporting member, or terminal board upon which they are to be mounted, be semirigid and yieldable around the portion of the terminal board or aperture which is to receive the snap-in contact pin. This is required so that the surrounding wall of the aperture will expand at the time that the snap-in contact pin is inserted into position. If a rigid type of board were employed the attempted insertion of a snap-in type of contact pin will cause the destruction of the board or at least a fracture of that portion of the board adjacent the aperture in which the contact pin is to be placed. Such contact pins are not useable with rigid type terminal boards. In addition, the thickness of the terminal board must be carefully chosen to match the spacing between the various shoulder elements of the snap-in contact pin; otherwise, a loose fit would result and the contact pin would be free to move in a direction perpendicular to the surface of the board. A wide variety of sizes of snap-in contact pins is required for use with varying thicknesses of terminal boards.

A second type of contact pin found in the prior art, which provides a double-ended terminal contact pin, is the type which is snapped together upon installation. In a typical device of this type a first contact portion is inserted within the terminal board and has at one end thereof a shoulder to be brought into contact with a first surface of the supporting member or terminal board. A second portion of the contact pin is then brought in from the opposite side of the terminal board and snapped into position within first contact portion. Again, variations in the thickness of the terminal board must be met by different sized contact pins to properly match the spacing between the shoulder of the contact pin when assembled. Failure to match the contact pin to the thickness of the terminal board will result in an improper coupling between the two contact portions and result in an easily separable contact pin. Additionally, the ability to separate the contact portions is dependent upon the type of fit achieved between the two contact pin portions as assembled. Some degree of force exerted on either one of the contact pins will usually result in separation of the two portions of the double-ended terminal.

The third type of contact pin found in the prior art is that which is staked to position in the terminal board. This type of device generally provides a number of cutout sections whose intermediate lands will form the second shoulder of the contact pin when staked. However, contact between the terminal board and the shoulder formed due to the staking operation is incomplete in a sense that only a portion of the terminal board surface is contacted by the formed shoulder of the contact pin. As a result the contact pin is often free to rotate forming an unstable contact. Additionally, due to the cut-out portions of the contact pin the overall contact pin is greatly weakened and may be easily broken off at the terminal board.

SUMMARY OF THE INVENTION The present invention overcomes the difficulties noted above with respect to the three representative types of prior art contact pins. This is done by providing a unitary feed through contact pin which includes a lower contact portion terminating in a shoulder which is made to abut one surface of a supporting member such as a terminal board, a deformable shank portion which passes through an aperture in the terminal board and which will provide a second shoulder on the opposite surface of the terminal board and a second contact pin coupled to the deformable shank portion. A set of dies, having nests therein, the first to receive the first contact portion and the shoulder and the second to receive the second contact portion and to form a shoulder on the opposite side of the terminal board are made to fit about the contact pin and to support the first contact portion and shoulder while forming the second shoulder. Because the contact pin is unitary it is not subject to separation as is true of the double-ended type of terminal which is snapped together for assembly. Further, since the deformable shank portion is made for a light press fit with the aperture in the terminal board it is not necessary that a semi-rigid terminal board be employed with this type of contact pin. Also, since the shoulder on the second surface of the terminal board is made at the time of crimping few limitations as to the thickness of the terminal board is placed upon this particular contact pin. Finally, since the shoulder formed in the crimping operation extends around the complete 360 periphery of the contact pin and since there are no apertures cut out within the contact pin itimproved form of contact pin having one preformed shoulder and a second shoulder formed during the attachment operation of the contact pin to a terminal board or other supporting member.

It is yet another object of this invention to provide an improved form of contact pin having high physical strength and which can be secured to terminal boards having a wide variety of thicknesses.

It is still another object of this invention to provide a unitary contact pin having first and second contact portions of a first wall thickness and an intermediate shank portion of lesser wall thickness adapted to be secured to a terminal board in a staking operation.

It is yetanother object of this invention to provide an improved form of contact pin having solid contact portions.

It is yet another object of this invention to provide an improved form of contact pin having nonsymmetrical contact portions for the receipt of wire wrap connections.

Other objects and features of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention, and the best modes which have been contemplated for carrying it out.

BRIEF DESCRIPTION OF THE DRAWING In the drawings:

FIG. 1 is a side elevation of a contact pin constructed in accordance with the concepts of the invention and shown positioned in a die set, shown in section.

FIG. 2 is a side elevation of the contact pin of FIG. 1 shown in the crimped position with the die set, shown in section, closed about the contact pin. 7 7

FIG. 3 is a side elevation of the connector pin of FIG. 1 completely installed upon a terminal board, shown in section.

FIG. 4 is a side elevation, in section, of the contact pm of FIG. 1 taken along the line 4-4.

FIG. 5 is a side elevation, in section, of a further embodiment of a contact pin constructed in accordance with the concepts of the invention also taken along a line similar to 4-4 of FIG. 1.

FIG. 6 is a sectional view, of the contact pin of FIG. 1, taken along the lines 66 of FIG. 1.

FIG. 7 is a sectional view of afurther embodiment of a contact pin constructed in accordance with the concepts of the invention and taken along a line similar to I 6-6 ofFIG. 1.

Similar. elements are given similar reference charac ters in each of the respective figures.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning now to FIG. 1 there is. shown a contact pin 10 constructed in accordance with the concepts of the invention. The contact pin 10 has a first cylindrical contact portion 12 which has a uniform diameter along its entire length and which terminates in a shoulder 14. The

portion 18 is coupled to a second cylindrical contact portion 22 having a uniform diameter along its entire length equal to that of the first cylindrical contact portion 12. The use of uniform and equal first and second cylindrical contact portions without any enlargements at the ends thereof permits the use of the same female terminal connector with both contact portions.

The contact pin 10 is positioned into the nests of a die set having a lower die portion 24. The first contact portion 12 will fit into the die nest 26 of the first die portion 24. Die portion 24 also has a nest 28 having a transverse dimension approximately that of the shoulder 14. The width nest 28 is slightly in excess of the width of the shoulder portion 14 and will provide a supporting shoulder 30 to contact the shoulder portion 14. The extra width of the die nest 28 is provided to accept any expansion of the shoulder 14 during the staking operation to be described below. The upper die portion 32 has a die nest 34 to accept the second contact portion 22 and a further nest portion 36 which will form, from the deformable shank portion 18, an additional shoulder to be described below. The die set comprising the lower die portion 24 and the upper die portion 32, as shown in FIG. 1, in a position prior to the application of a crimping force to the contact pin 10.

Turning now to FIG. 2, the upper die portion 32 and lower die portion 24 have been closed to stake the contact pin 10 to the terminal board 16. As can be seen in FIG. 2, the closing of the die portions 24 and 32, against the contact pin 10, has caused the deformable shank portion 18 to deform forming a shoulder on the opposite side of the terminal board 16 from that upon which the shoulder 14 is positioned. FIG. 3 illustrates the completed coupling of the contact pin 10 to the terminal board 16 showing that the shoulder 14 is positioned adjacent the underside of the terminal board 16 while the deformable staking portion, which has been deformed by means of the die set 32, now forms a shoulder on the upper surface of the terminal board 16. a coupling, between the deformable shank portion 18 and the upper surface of the terminal board 16 is achieved along the entire periphery of the contact pin 10 and there are no weakened points which would permit the breaking off of the upper contact portion 22 as is found in the prior art devices described above.

In FIG. 4 there is shown aside elevation of a section of the contact pin 10, of FIG. 1, taken along the line 4-4. This figure shows that the wall thickness of the first contact portion 12 and the second contact portion 22 are approximately the same and both are greatly in excess of the wall thickness of the shoulder 14 and the deformable shank portion 18. In this manner the deforming of the deformable shank portion 18 and of the shoulder 14 are facilitated. It has been found that by constructing the contact pin 10 of a uniform wall thickness throughout, attempts to stake the contact pin 10 to a terminal board by deforming the deformable shank portion 18 generally results in the shearing of the material of the deformable shank portion causing destruction of the contact pin 10.

The contact pin 10 of FIG. 4 may be constructed by first cutting from a planar sheet of metal a blank having the general shape of the contact pin 10. The material will be chosen to have a thickness equal to the desired wall thickness of the contact portions 12 and 22. The blank is then rolled to form the contactpin 10 and is then subjected to tensional forces at the contact portions 12 and 22 to'cause the elongation and thus the decrease in the wall thickness of the shoulder 14 and the deformable shank portion 18. The reduction in the wall thickness, at the shoulder 14, and the deformable shank 18, facilitates the forming of both of these portions and also permits full contact between the deformable shank portion in the aperture of a terminal board as a result of the staking operationFurther, the manner of staking of the contact pin 10 to the terminal board, at the portion of the deformable shank 18, prevents the distortion of either of the contact pin portions 12 or 22 during the staking operation. Such distortion often occurred in prior art devices which employed punched apertures and alternating lands to provide the desired upper shoulder during the crimping operation.

In FIG. an alternative pin arrangement is shown. Instead of providing the hollow contact portions 12 and 22, the contact portions 12 and 22' are provided as solid members. Deformable shank portion 18 and the shoulder '14 will still be provided with relatively thin wall thickness to accommodate the crimping operation as was described above.

Turning now to FIG. 6 there is shown a sectional view of the contact portion 12 of the contact pin 10 taken along the lines 66. As can be seen, the contact portion 12 is hollow, and is of circular cross-section. However, although the pin is shown to have a circular cross-section any other convenient regular or nonregular geometric form can be employed, such as hexagonal, square, rectangular or the like. In FIG. 7 a variation of either, or both, of the contact portions 12 and 22 is shown. The first contact portion 12" is shown to be U-shaped and to be made of solid material. This form is found extremely suitable for wire-wrap operations by providing two right angle contact points 40 and 42 required to hold the wirewrap connection while the arcuate portion 44 provides the maximum contact surface between the wires wrapped about the contact portion 12".

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to the preferred embodiments it will be understood that various omissions and substitutions and changes of the form and details of the devices illustrated and in their operation may be made by those skilled in the art, without departing from the spirit of the invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A double ended contact pin adapted to be rigidly secured in an aperture in a mounting board by deforma-' tion of a portion thereof comprising: first and second oppositely directed, equal diameter, tubular, cylindrical contact portions having closed opposite ends; the outer surface of said contact pin being continuous and substantially uninterrupted; a hollow deformable, annular shank portion integral at its respective ends with one of said first and second contact portions; said shank portion securing said first and second contact portions together; said shank portion comprising: an enlarged annular shoulder adjacent said first contact portion for engagement with a first surface of a mounting board and a relatively enlarged, tubular portion adjacent said second contact portion dimensioned to pass through an aperture in a mounting board and adapted to be deformed into engagement with the second surface of said mounting board whereby said contact pin is rigidly coupled to said supporting member.

2. A contact pin as defined in claim 1 wherein the wall thickness of said shank portion is relatively less than the wall thickness of said first and second contact portions.

3. A double ended contact pin adapted to be rigidly secured in an aperture in a mounting board by deformation of a portion thereof comprising: first and second oppositely directed, axially aligned contact portions of solid cross-section; a hollow, deformable, annular shank portion integral at its respective ends with one of said first and second contact portions, said shank portion securing said first and second contact portions together; said shank portion comprising: an enlarged, annular shoulder adjacent said first contact portion for engagement with a first surface of a mounting board and a relatively enlarged, tubular portion adjacent said second contact portion dimensioned to pass through an aperture in a mounting board and adapted to be deformed into en-/ gagement with the second surface of said mounting board whereby said contact pin is rigidly coupled to said supporting member.

4. A contact pin as defined in claim 3 wherein a portion of the outer surface of one of said first and second contact sections is formed to provide a flattened surface along a substantial portion of its length; and a medial, longitudinal slot extending along said flattened surface of said formed contact portion extending from the surface of said contact portion towards the radial center thereof.

References Cited UNITED STATES PATENTS 2,386,171 10/1945 Wild 339275 X 2,533,987 =12/1950 Bahr 339220 X 3,128,813 4/1964 Davis et a1 15141.72 2,673,336 3/1954 Peters 339-220 3,155,448 1 1/1964 Korsgren 3399-4X FOREIGN PATENTS 942,245 2/ 1949 France.

RICHARD E. MOORE, Primary Examiner U.S. Cl.X.R. 339248

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