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`Feinmetall Exhibit 2013
`FormFactor, Inc. v. Feinmetall, GmbH
`IPR2019-00082
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`Page 1 of 6
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`

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`US. Patent
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`Apr. 12, 1988
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`Sheet 1 of 3
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`4,737,114
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`HGJ
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`HG4A
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`HG43
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`I 93
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`a9
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`l l
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`“m“m“
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`HGZ
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`W] W
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`31A
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`3‘
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`6 I
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`6’IBIA’6
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`32A/33 _
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`Page 2 of 6
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`Page 2 of 6
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`

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`US. Patent
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`Apr. 12, 1988
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`Sheet 2 of 3
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`4,737,114
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`Page 3 of 6
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`

`

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`US. Patent
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`Apr. 12,1988
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`Sheet 3 of3
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`4,737,114
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`SEER/11R;
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`PRIORART
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`PRIORART
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`FIG. 17
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`FIG. 16
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`HA
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`H
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`HA
`IO
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`HA
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`I
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`HA
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`Page 4 of 6
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`Page 4 of 6
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`

`

`15
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`25
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`ELECTRICAL CONTACT PIN
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`CROSS-REFERENCE TO RELATED
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`APPLICATIONS
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`This application is a continuation of Ser. No. 857,948
`filed May 1, 1986.
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`BACKGROUND OF THE INVENTION
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`The present invention relates to electrical contact
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`pins and, more particularly, to an electrical contact pin
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`having a compliant part.
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`Electrical contact pins having a compliant part to be
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`fitted into a plated hole of a printed circuit board for
`mechanical fixation and electrical connection thereto
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`are well known. FIGS. 15 and 17 show two examples of
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`conventional compliant electrical contact pins.
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`The electrical contact pin of FIG. 15, so called “eye
`20
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`of the needle” compliant pin, is made by stamping from
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`a sheet of springy conductive metal so that it has an
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`opening 11 at the center of a compliant part 10 to give
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`a spring property to the compliant part. As FIG. 16
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`shows this compliant part is fitted into a plated aperture
`1 of a circuit board so that its four corners 11A elasti-
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`cally cut into the conductive wall of the plated aperture
`1 for mechanical
`fixation and electrical connection
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`thereto.
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`The electrical contact pin of FIG. 17 is made by first
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`stamping out a compliant part 20 from a sheet of springy
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`conductive metal. Then,
`the compliant part 20 is
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`sheared to form a pair of legs 21 and 22. These legs are
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`then offset with respect to each other along the shear
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`plane so as to give a spring property to the compliant
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`part. As FIG. 18 shows, the compliant part is fitted into
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`a plated aperture 2 of a circuit board so that a comer
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`21A of the offset leg 21 and a corner 22A of the offset
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`leg ‘22 elastically cut into the conductive wall of the
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`plated aperture 2 for meachincal fixation and electrical
`connection.
`'
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`Recently, electronic parts are densely mounted on a
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`circuit board, and the diameter of plated apertures has
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`become smaller than before. Consequently, there is a
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`45
`need to make the compliant part of an electrical contact
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`pin smaller than before. However, it is practically im-
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`possible to punch out an opening 11 having a diameter
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`of less than about 0.60 mm (0.024 inch) in the compliant
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`part of an eye of the needle compliant pin of FIGS. 15
`50
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`and 16. Although the compliant part of a contact pin of
`FIGS. 17 and 18 is relatively well fitted into a small
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`aperture, there are only two points in contact with the
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`conductive wall of a plated aperture, as shown in FIG.
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`18, and the contact pin tends to turn in fitting operation.
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`Consequently, the fitting operation requires an extra
`force to counter the turning force.
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`SUMMARY OF THE INVENTION
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`Accordingly, it is an object of the invention to pro-
`60
`vide an electrical contact pin useful for an easy to fit
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`into a small plated aperture of a circuit board.
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`According to the invention there is provided an elec-
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`trical contact pin haing a compliant part to be fitted into
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`a plated aperture having a diameter of no more than
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`about 0.94 mm (0.037 inch). The compliant part consists
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`of a pair of elongated legs coming together at opposite
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`shear ends and having generally straight inside walls
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`which are not offset with respect to each other along a
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`2
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`shear plane and define a thin slot. The thin slot has a
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`length and a width greater than those of the shear ends.
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`An advantage of the invention is that the the width of
`the thin slot so small that the outside diameter of the
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`compliant part of a contact pin is sufficiently small to fit
`into a plated aperture as small as no more than 0.94 mm.
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`. Other objects, features, and advantages of the inven~
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`tion will be apparent from the following description
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`taken in conjunction with the accompanying drawings.
`BRIEF DESCRIPTION OF THE DRAWINGS
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`FIG. 1 is a perspective view of an electrical contact
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`pin embodying the present invention;
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`FIGS. 2 and 3 are sectional views taken along the
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`lines II—II and III—III, respectively, of FIG. 1;
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`FIGS. 4 through 11 illustrate a method of making the
`electrical contact pin of FIG. 1;
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`FIG. 12 is a sectional view of the compliant part of
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`the contact pin fitted into a plated aperture;
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`FIG. 13 is a perspective view of another embodiment
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`of the compliant part of an electrical contact pin ac-
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`cording to the invention;
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`FIG. 14 is a sectional view taken along the line
`XIV—XIV of FIG. 13;
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`FIG. 15 is a perspective view of an electrical contact
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`pin according to the prior art;
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`FIG. 16 is a sectional view of the compliant part of
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`the contact pin of FIG. 15, which is fitted into a plated
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`' aperture;
`30
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`FIG. 17 is a perspective view of another electrical
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`contact pin according to the prior art; and
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`FIG. 18 is a sectional view of the compliant part of
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`the contact pin of FIG. 17, which is fitted into a plated
`aperture.
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`DESCRIPTION OF THE PREFERRED
`
`
`EMBODIMENTS
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`In FIGS. 1, 2, and 3, an electrical contact pin 3 con-
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`sists of a head 26, a shoulder 28, and a fixing or compli-
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`ant part 30 to be fitted into a plated aperture. The com-
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`pliant part 30 has a pair of elongated legs 6 to define a
`thin slot 33 with shear ends 31 and 32 at its upper and
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`lower ends. Facing inside walls 33A and 33B of the
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`elongated legs 6 are not offset with respect to each
`other along the shear plane. The shear ends 31 and 32
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`are coined at 31A and 32A, respectively, for making a
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`fine adjustment of the slot width. The elongated leg 6
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`has a long straight central portion, a pair of short
`curved portion, and a pair of short straight shear end
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`portions at which two legs join together.
`FIGS. 4 through 11 illustrate how to make the elec-
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`trical contact pin of FIG. 1.
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`In FIG. 4A, an array of rectangular openings 5 are
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`punched out from a sheet of springy conductive metal 4
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`to form an elongated portion 6 having a rectangular
`crosssection, the diagonal length of which is less than
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`the diameter of a plated aperture into which the finished
`compliant part is to be fitted.
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`In FIG. 5, the elongated portion 6 is sheared in the
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`axial direction to form a pair of elongated legs 6 which
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`are offset with respect to each other along the shear
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`plane. FIG. 6 shows in section the resulting shear end
`portion, and FIG. 7 shows in section the offset elon-
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`gated leg portion.
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`In FIG. 8, the offset elongated legs 6 are pressed
`between press elements 8 so that they return to the
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`plane of the sheet material 4 and expand outwardly to
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`such an extent that the elongated legs have been offset
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`4,737,114
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`lo
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`35
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`55
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`65
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`1
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`Page 5 of 6
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`Page 5 of 6
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`

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`4,737,114
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`10
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`3
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`with respect to each other along the shear plane. The
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`result is a thin slot 33 produced between the two elon-
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`gated legs 6, as shown in the Figure, so that the diagonal
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`length of cross-section of the elongated legs 6 becomes
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`greater than the diameter of a plated aperture.
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`In FIG. 4B, by cutting the metal sheet along a dotted
`line 4A of FIG. 4A, a pin element 3A connected to a
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`strip 4B is formed. FIGS. 9 and 10 show in section the
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`shear end portion and the expanded straight leg portion,
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`respectively. It is noted that the short shear ends 31 and
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`32, which have been made by the shearing operation,
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`remain at the upper and IOWer ends of the long thin slot
`33.
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`In FIG. 11, the shear ends 31 and 32 are coined by
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`means of press elements 9 to adjust the width of the thin
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`slot 33 and, in turn, the diagonal length of cross-section
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`of the elongated legs 6.
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`Finally, the pin element 3A is severed from the strip
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`43 to complete a contact pin 3 with a compliant part 30
`as shown in FIG. 1.
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`FIG. 12 shows the compliant part 30 in sectiOn which
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`is fitted into a plated aperture 2. Four corners 30A of
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`the compliant part uniformly cut into the conductive
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`wall of the plated aperture 2.
`FIG. 13 shows another embodiment of the electrical
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`contact pin according to the invention. This compliant
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`part 40 is identical with that of contact pin 3 of FIG. 1
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`except that the inside edges 43A of each leg 6 are co-
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`nined as well as the upper and lower shear ends by
`3O
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`means of suitably shaped press elements. The shape of a
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`compliant part may be changed by using differently
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`shaped press elements.
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`According to the invention, the width of a thin slot
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`formed at the center of a compliant part of a contact pin
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`is so small that the outside diameter of the compliant
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`part is sufficiently small to fit into a plated aperture as
`small as about 0.6 mm in diameter. When fitted into a
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`4
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`plated aperture, the four corners of the compliant part
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`cut into the inside wall of the plated aperture so that the
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`forces to be applied are balanced, making the fitting
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`operation easier and the resultant electrical and me-
`chanical connection better than before. In addition to
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`the complian? property of the legs, the shear ends at the
`upper and lower ends of a thin slot are compressed
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`inwardly, thus facilitating the fitting operation and re-
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`ducing the possibility of damaging the plated aperture.
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`While a preferred embodiment of the invention has
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`been described using specific terms, it is to be under-
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`stood that changes and variations may be made without
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`departing from the spirit and scope of the invention as
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`recited in the appended claims.
`I claim:
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`1. An electrical contact pin having a compliant part
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`to be fitted into a plated aperture having a diameter of
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`no more than about 0.94 mm (0.037 inch); said compli-
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`ant part comprising;
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`a pair of opposed elongated outwardly bowed legs
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`which have been sheared apart, whose ends are
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`joined to respective ends of said pin, said legs being
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`separated by a slot, said legs each having a central
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`portion and end portions which are parallel to the
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`longitudinal axis of said pin, said central portions
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`being spaced farther apart outwardly than said end
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`portions, said central portion of each said leg being
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`joined to its respective said end portions by curved
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`segments, said slots having ends which extend lon-
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`gitudinally beyond said curved segments, said slot
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`ends separating said end portions at both of said pin
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`ends so that they do not abut one another.
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`2. An electrical contact pin as recited in claim 1,
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`wherein said end portions are coined.
`3. An electrical contact pin as recited in claim 2,
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`wherein said central portions are coined.
`it
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`*
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`15
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`20
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`25
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`35
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`4O
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`45
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`50
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`55
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`60
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`65
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`Page 6 of 6
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`Page 6 of 6
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