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`Feinmetall Exhibit 2019
`FormFactor, Inc. v. Feinmetall, GmbH
`IPR2019-00082
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`Page 1 of 19
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`US. Patent
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`Feb. 4, 1997
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`FIG.|
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`Sheet 1 of 13
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`US. Patent
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`Feb. 4, 1997
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`Sheet 2 of 13
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`_ 5,599,194
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`FIG.3
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`Page 30f 19
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`Page 3 of 19
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`US. Patent
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`Feb. 4, 1997
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`Sheet 3 of 13
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`5,599,194
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`FIG.4
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`Page 40f 19
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`Page 4 of 19
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`US. Patent
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`Feb. 4, 1997
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`Sheet 4 of 13
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`5,599,194
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`FIG.5
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`Page 50f 19
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`Page 5 of 19
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`US. Patent
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`Feb. 4, 1997
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`Sheet 5 of 13
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`FIG.6
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`Page 60f 19
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`Page 6 of 19
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`US. Patent
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`Feb. 4, 1997
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`Sheet 6 of 13
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`F I G. 7
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`5,599,194
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`(mm)
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`D'ISTORTION
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`0
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`0.:
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`0.2
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`0.4
`0.3
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`WIPING (mm)
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`05
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`Page 7 of 19
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`Page 7 of 19
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`US. Patent
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`Feb. 4, 1997
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`Sheet 7 of 13
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`FIG.9
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`32 45-4 51-4
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`5"‘5
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`36
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`Page 80f 19
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`Page 8 of 19
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`U.S. Patent
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`Feb. 4, 1997
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`Sheet 8 of 13
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`35
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`5|
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`gx
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`mHmemm 32
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`33:15,":v 3mm
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`Page 90f 19
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`53-4
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`Page 9 of 19
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`Sheet 9 of 13
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`FIG. l2
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`5,599,194
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`Page 10of19
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`Page 10 of 19
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`Feb. 4, 1997
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`Sheet 10 of 13
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`FIG.
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`I4
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`Page11of19
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`Page 11 of 19
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`US. Patent
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`Feb. 4, 1997
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`Sheet 11 of 13
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`FIG.I5
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`Page 12 of19
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`US. Patent
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`Sheet 12 of 13
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`F I G. l6
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`Page 13 of19
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`Page 13 of 19
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`US. Patent
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`Feb. 4, 1997
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`Sheet 13 of 13
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`F I G. l8 (PRIOR ART)
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`illlillll
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`Page 14 of19
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`Page 14 of 19
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`1
`IC SOCKET AND ITS CONTACT PIN
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`5,599,194
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`CROSS—REFERENCE TO RELATED
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`APPLICATIONS
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`This Application is a Continuation of applicant’s co-
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`pending Patent Application Ser. No. 07/931,925 filed Aug.
`18, 1992.
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`FIELD OF THE INVENTION
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`The present invention relates to a contact pin for IC
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`sockets for making electrical connections between leads of
`an IC device and external circuits.
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`More particularly, the invention concerns multiple, very
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`thin wall contact pins aligned at very close intervals for use
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`in a multi-pin IC socket.
`Also, the invention relates to an IC socket for ease in
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`electrical connection with external circuits, with the IC
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`socket having an IC device or similar electronic parts
`mounted thereon.
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`More particularly, the invention concerns an IC socket
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`having contact pins aligned at very close intervals on a
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`socket body for contact with leads of an IC device for
`electrical connections with leads of external circuits.
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`Further, the invention relates to the structure of an IC
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`socket for electrical connection with external circuits, with
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`the IC socket having an IC device or similar electronic parts
`mounted thereon.
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`BACKGROUND OF THE INVENTION
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`In Japanese Patent Application Laid-Open 61—150249, a
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`ring-like contact pin of thin wall construction is proposed for
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`use in an IC socket which is used for mounting an IC device
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`or similar electronic parts (see FIG. 17). In an IC socket, as
`shown in FIGS. 18 and 19,
`the leads of an IC device
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`positioned on top 3 of a multiple contact pin 10' (FIG. 17)
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`and aligned on a socket body 20 are pressed toward contact
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`pin 10‘ by pads 21-1 and 21—2 fitted on cover 21 linked on
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`socket body 20 by shaft 23 as the cover is closed.
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`However prior art pins similar to contact pins 10' have the
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`disadvantage of poor electrical connection due to an insu-
`lation of oxide film formed on the surfaces of the leads; and
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`each contact pin 10’, when pads 21—1 and 21—2 fitted on
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`cover 21 are pressed for connections of the leads and contact
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`pins 10' as cover 21 is closed.
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`Also, prior art contact pins similar to contact pin 10' have
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`the disadvantage that they are too weak to endure severe
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`plastic deformation as they are made of ring plates having a
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`very thin wall.
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`In view of the foregoing, it is an object of the present
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`invention to provide multiple contact pins of very thin wall
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`construction and having good electrical connection for an IC
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`socket without an oxide film insulation likely being formed
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`on the surface of leads and contact pins and without breaking
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`due to plastic deformation.
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`Further, prior art IC sockets having mount contact type
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`contact pins 10' have the disadvantage that it is hard to align
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`the leads of the IC device in positions between guide walls
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`provided in the IC socket. Furthermore, it has a disadvantage
`that the leads may be bent or broken if deformed when the
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`cover 21 is closed.
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`Accordingly, it is another object of the present invention
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`to provide an IC socket that has a feature for preventing the
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`position of an IC device from deviating and its leads from
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`2
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`being deformed. This allows the IC device to be automati-
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`cally positioned for secure contact between contact pins with
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`lead frames by simply placing the IC device in a limited
`range on a stage.
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`In recent IC sockets, numerous contact pins have to be
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`aligned at intervals closer than usual as the IC devices are
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`made more dense in order to make camera-equipped VTRs,
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`portable telephone sets, and similar electronic devices
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`smaller and with increased features. Such finer alignment
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`leads have a more difiicult task of forming the guide walls
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`for positioning the contact pins and guiding and restricting
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`the contact action of the contact pins with leads.
`There is a disclosure about a connector for an IC mount-
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`ing board in Japanese Utility Model Application Laid Open
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`Sho 58—70687. In the disclosed connector there are projected
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`contact portions for mounting pins of the IC mounting board
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`on free ends of elastic contact arms. Guide pieces project in
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`the vicinity of the contact portions. The guide pieces are
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`positioned in guide grooves (guide walls) formed on a
`socket body to guide elastic displacements of the elastic
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`contact arms. A feature of the connector is the easy forming
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`of a socket body as the elastic contact arms corresponding to
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`the contact pins can be partly guided on their front free ends
`and rear fixed ends.
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`The inventors have also proposed multiple contact pins of
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`very thin wall construction having securing strength at very
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`close intervals for an IC socket in the Japanese Utility Model
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`Application Hei 3-41476. The contact pins, as shown in FIG.
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`1 have a ring-like contact arm 2 formed of a pair of arm
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`portions 2a and 2b opposing each other. Contact arm 2 also
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`has contact portion 3 formed at its front free end to contact
`a lead of an IC device (not shown). Contact arm 2 is
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`connected with the base of contact pin 10 by way of neck 1
`on its rear fixed end.
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`Contact pin 10 can have a secure contact action with the
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`lead of an IC device without twisting at its arm portions 2a
`and 2b, even if it is formed as a very thin construction. This
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`is because force F, exerted downward toward contact pin 10,
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`as shown in FIG. 2, is dispersed up and down by the pair of
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`opposed arm portions 2a and 211.
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`However, the prior IC socket described above has the
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`disadvantage that adjacent contact pins 10 may likely con—
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`tact each other as they tend to easily flex in an aligning
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`direction, although they have enough vertical strength to
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`endure force F as described above. As contact pins 10 are
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`embedded in the socket body, it is difficult to prevent them
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`from making contact at their mid portions in the construction
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`of the connector of Japanese Utility Model Application Laid
`Open Sho 58-70687 described above where the elastic
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`contact arm is guided by its front free end and rear fixed end.
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`Accordingly,
`is still another object of the present
`it
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`invention to provide an IC socket that allows contact pins
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`aligned at very close intervals to securely move.
`The contact pins of a conventional IC socket shown in
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`FIG. 18 are usually 0.2 to 0.4 mm thick. In order to prevent
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`adjacent contact pins from touching each other, the IC socket
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`has multiple guide walls provided therein. Since the guide
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`walls are aligned at relatively wide intervals, they are made
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`of synthetic resin and integrated in the socket body.
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`As described above, the contact pins are designed so that
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`as force F is exerted down on the top portion of any of the
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`contact pins, it can be effectively dispersed by the arm
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`portions. The contact pins can be made to securely contact
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`the leads of the 1C device even when the contact pins are as
`thick as 0.13 to 0.18 mm.
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`However, although the contact pins of a conventional IC
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`socket can be made thin, it is extremely difficult to align
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`5
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`10
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`15
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`20
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`60
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`them at very narrow intervals as the multiple guide walls are
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`made of synthetic resin to integrate with the socket body. In
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`other words, the guide walls may have insufficient filling
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`with a molding material when injection—molded.
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`In view of this, it is still another object to provide an IC
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`socket that can be molded and assembled easily and efiec-
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`tively for an increased number of pins of an IC device
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`aligned at narrower intervals.
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`10
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`by a cover linked with socket body which is in a closed
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`position. Each contact pin has a ring contact arm comprising
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`a pair of arm portions opposing each other, a guide and a
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`restriction portion formed on a front free end and a rear fixed
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`end of the contact arm of the contact pin as a guide wall in
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`order to align the contact pin on the socket body. The contact
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`arm has insulating areas, at least, on the front free end and
`the rear fixed end.
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`Further, the IC socket is characterized by: a multiple of
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`ring-like contact pins aligned on a socket body placed on
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`leads of an IC device; the leads being pressed in order to
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`press the contact pins onto the respective leads as a cover
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`having a pad linked with the socket body is closed. A shaft,
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`having guide walls fitting between the contact pins,
`is
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`inserted in rings of the contact pins and fixed on the socket
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`body so that the contact pins are isolated from each other.
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`Furthermore, the IC socket is characterized by: both ends
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`of the shaft fitting in resting grooves and formed on posts
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`provided at comers of the socket body, and keys fitting in
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`keyways of both ends of the shaft and the resting grooves to
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`lock the shaft being. Both ends of the fitted and locked shaft
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`are enclosed by a cover, with the shaft integrated with the
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`socket body by fastening means.
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`The above and other features of the present invention will
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`be more fully understood from the following detailed
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`description and the accompanying drawings, in which:
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`BRIEF DESCRIPTION OF THE DRAWINGS
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`FIG. 1 is a front view of a first embodiment of a contact
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`pin according to the present invention.
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`FIG. 2 is an illustration of the contact pin of FIG. 1 to
`which a force is exerted.
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`FIG. 3 is an illustration of the wiping action of the contact
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`pin according to the present invention.
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`FIG. 4 shows a single-plate contact pin of a shape similar
`to the one in FIG. 3.
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`FIG. 5 and FIG. 6 show other shapes of contact pins with
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`parts of ring-like arms cut out.
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`FIG. 7 is a front view of a contact pin with a restriction
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`member added thereto according to the present invention.
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`FIG. 8 is a graph showing the amount of wiping (rubbing)
`on the axis of abscissas and the distortion on the axis of
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`ordinates.
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`FIG. 9 is a plan view of a second embodiment of an IC
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`socket according to the present invention.
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`FIG. 10 is a partly cross-sectioned side View of the second
`embodiment.
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`FIG. 11 is a cross-sectioned side view illustration of the
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`second embodiment.
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`FIG. 12 is a cross-sectioned side view of major parts of a
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`third embodiment of an IC socket according to the present
`invention.
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`FIG. 13 is a plan view of the third embodiment.
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`FIG. 14 illustrates perspective views of a socket body and
`guide wall assemblies of a fourth embodiment of an IC
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`socket according to the present invention.
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`FIG. 15 is a partly exploded perspective view illustrating
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`support of the guide wall assembly of the IC socket of the
`fourth embodiment.
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`FIG. 16 is a partly exploded perspective view illustrating
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`insertion of the guide wall assembly and contact pin of the
`IC socket of the fourth embodiment.
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`15
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`20
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`BRIEF DESCRIPTION OF THE INVENTION
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`invention is
`Contact pin 10 according to the present
`described with reference to FIG. 3. Pin 10 is moved as
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`indicated in phantom if force F is exerted down on top 3
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`thereof. It is seen by analysis that contact pin moves around
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`a center of motion 0. Center of motion 0 is at a position
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`located a little outside the boundary of contact pin 10.
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`FIG. 4 shows a single-plate contact pin 10 of a shape
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`similar to the one in FIG. 3. Center of wiping motion 0 at
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`contact portion due to force F is within the boundary of
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`contact pin 10.
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`FIGS. 5 and 6 show contact pins 10 of other shapes having
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`parts of ring-like arms cut out. Center of wiping motion 0 of
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`any of contact pins 10, is located substantially within the
`boundaries.
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`FIG. 8 is a graph showing the amount of wiping on the
`abscissas axis and distortion on the ordinate axis. Curves
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`A,B,C and D correspond to the devices shown in FIGS. 3,4,5
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`and 6. It
`is found from the graph that contact pin 10
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`comprising a ring of two arm portions according to the
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`present invention is low in wiping when distortion is largest.
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`In this case, top 3 of the ring, as shown in FIG. 7, must not
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`be moved down linearly with zero wiping.
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`In order to prevent breaking due to plastic deformation
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`when excessive force F is exerted on top 3 of contact pin 10,
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`the ring should have restriction member 19 provided therein
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`as shown in FIG. 7. Restriction member 19 keeps neck 1 of
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`contact pin 10 from being deformed.
`40
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`In contact pin 10 according to the present invention, the
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`distortion caused by a pad on the cover as it closed is large
`as two opposite vector forces are exerted on two arm
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`portions. Wiping also can be securely made. Restriction
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`member 19 provided in the ring prevents the arm portions
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`from being unnecessarily distorted in event of an accident
`due to excessive force.
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`The IC socket comprises in combination: a socket body
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`having multiple contact pins aligned for electrical connec-
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`tion with the leads of an IC device, a platform for mounting
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`the IC device thereon, actuation fitting projections, spring
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`means, an intermediate plate which is placed vertically to
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`allow movement upward of the spring way, a slope for
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`guiding the leads of the IC device, a rest for positioning the
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`IC device, a floating plate for restricting the intermediate
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`plate from moving up, and a cover being aligned with the
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`socket body, a pad and projections capable of fitting with
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`projections of the intermediate plate. The above is charac-
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`terized by the projections of the cover pressing the projec-
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`tions of the intermediate plate to lower the it down in order
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`to the sides of the contact pins as the cover is closed, the IC
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`device mounted on the platform of the intermediate plate is
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`put in position on the rest, and the pad of the cover presses
`the contact pins into electrical connection with the leads.
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`Also, the IC socket is characterized by multiple contact
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`pins aligned on a socket body placed on leads of an IC
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`device, and pressed onto the leads as the IC device is pressed
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`25
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`35
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`65
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`Page 16 of19
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`Page 16 of 19
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`6
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`5
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`FIG. 17 is a front view of a conventional contact pin.
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`FIG. 18 is a plan view of a conventional IC socket.
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`FIG. 19 is a partly cross-sectioned side view of the
`conventional IC socket in FIG. 18.
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`DETAILED DESCRIPTION OF THE
`
`
`INVENTION
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`10
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`15
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`20
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`25
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`30
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`35
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`Embodiment 1
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`FIG. 1 shows a contact pin 10 of a first embodiment
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`according to the present invention. Contact pin 10 cannot be
`twisted or fall down even if its wall thickness is made thin,
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`since a force F, exerted downward on contact pin 10, is
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`dispersed upward and downward by its two arms as shown
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`in FIG. 2. In addition, contact pin 10 has little wiping
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`(rubbing) even if greatly distorted since the wiping center is
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`deviated a little out of its form. For these reasons, contact pin
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`10 is optimum for a lead frame of a short type which tends
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`to have substantially more pins.
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`As shown in FIG. 7, contact pin 10 can have restriction
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`member 19, such as a pin, provided at a left end inside a ring
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`of contact pin 10 to prevent plastic deformation from
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`breaking the contact.
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`As described above, contact pin 10 according to the
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`present invention has the advantage that it cannot be twisted
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`or fall down even if it is thin. It can be securely wiped
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`against the lead of an IC device. The restriction member
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`provided in the ring prevents the arm portions from being
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`unnecessarily distorted in the event of an accident causing
`excessive force.
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`Embodiment 2
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`FIGS. 9 through 11 show a second embodiment of the IC
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`socket according to the present invention. The arrangements
`and parts in the figures are identical with those in a con-
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`ventional IC socket shown in FIGS. 18 and 19, and are
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`indicated by the same numbers as in FIGS. 18 and 19. FIG.
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`9 is a plan view with the cover open. FIG. 10 is a partly
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`cross-sectioned side view of the IC socket having no 1C
`mounted with the cover closed. FIG. 11 is a cross-sectioned
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`side view for the IC socket having the 1C mounted with its
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`right half closed and the left half open.
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`In the figures, base 32 has contact pins 37 of very thin wall
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`construction (around 0.12 mm) placed therein at narrow
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`intervals. Base 32, as shown in FIG. 9, is integrated with
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`socket body 31 at four points by rivets 45-1 through 45—4.
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`Each of contact pins 37 is partitioned by guide walls
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`provided on intermediate plate 33 extending upward on base
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`32. There are provided coil springs 48 to produce upward
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`spring force through bosses provided at four positions on the
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`intermediate plate 33. (Two of the four positions are shown
`in FIG. 11).
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`Above intermediate plate 33, is provided floating plate 34
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`to prevent
`intermediate plate 33 from moving upward.
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`Floating plate 34 can move up and down by coil springs 49
`and its upper movement is restricted as shown in FIG. 10.
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`Namely, floating plate 34 is restricted in its upward move—
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`ment by a plurality of stopping pawls 34-1 provided on
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`stopping portion 32-1 on base 32 side and floating plate 34.
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`Socket body 31 has cover 35 hinged by pin 43 as in the
`conventional IC socket.
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`If 1C device 59 is mounted on stage 33-1 and provided
`around a center of intermediate plate 33 as shown in FIG. 11,
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`IC device 59 starts moving downward along slope 34—2 of
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`floating plate 34 even if it is not placed in position as shown
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`in the shaded area. IC device 59 moves into position to be
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`Page 17 of19
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`mounted on stage 33-1 provided around the center of
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`intermediate plate 33. As cover 35 is closed, projections
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`50-1 and 50-2 provided on cover 35 press projections 53-1
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`and 53-2 of intermediate plate 33 to simultaneously start
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`moving downward stage 33-1. IC device 59 then is posi-
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`tioned below rest 34-3 of floating plate 34.
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`With the operation described above,
`the IC leads are
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`gradually moved along a straight portion from slope 34—2 to
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`be put in position on rest 34—3. Pad 35—1 of cover 35 is
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`loaded to properly press the IC leads so that they can contact
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`the contact pins for electrical connection. This allows the
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`partition walls of intermediate plate 33 to move up and down
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`along spring portions of the contact pins even when the
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`contact pins are very thin. This prevents the contact pins
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`from being twisted or collapsing.
`So far, the second embodiment has been described with
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`the use of the IC device of a QFP (quad flat package) type.
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`Of course, it can be applied to any lead shapes of straight and
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`bent type. It also has been described for separation of socket
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`body 31 and base 32. Alternatively, these can be integrated
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`together.
`As described above, the IC socket according to the present
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`invention can move the IC device down along the slope and
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`straight portion of the guide walls to place it in position on
`the rest.
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`In addition, contact pins of even very thin construction
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`allow the partition wall of the intermediate plate to move up
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`and down along the deformation of the spring portion to
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`restrict both ends of the spring portion. This prevents contact
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`pins from being twisted and collapsing.
`Embodiment 3
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`FIGS. 12 and 13 show a third embodiment for the IC
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`socket according to the present invention. The arrangements
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`and parts in the figures are identical with those in the
`conventional
`IC sockets of FIGS. 18 and 19, and are
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`indicated by the same numbers as in FIGS. 18 and 19. The
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`shape of the contact pin 10 and other basic constructions of
`the 1C socket are the same as those in the conventional ones
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`or in the prior embodiment. A front free end of contact arm
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`2, as shown in FIG. 12, is put in socket body 66 to be guided
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`and restricted by one slit 65a of guide wall 65, and a rear
`fixed end of contact arm 2 is fastened in the other slit 65b of
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`guide wall 65. FIG. 13 shows many contact pins 10 arranged
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`on socket body 66.
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`In the figure, 67 is cover hinged to socket body 66 by shaft
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`68, and pad 69 is provided inside cover 67 to press contact
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`portion 3 of contact pins 10 to leads as cover 67 is closed.
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`Contact pins 10, as shown in FIG. 12, has an insulating
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`means 2c formed therefore which, for example, is formed by
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`coating an insulating material at least on the front free end
`and the rear fixed end of contact arm 2.
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`Since the IC socket according to the present invention is
`made up as described above, the leads of the IC device are
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`pressed to corresponding contact portions 3 as cover 67 is
`closed with the contact portions 3 of contact arms 2 of the
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`contact pins 10 having the respective IC device leads
`mounted thereon. This makes electrical contact of the IC
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`device with the contact pins 10. Each of contact arms 2, of
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`contact pins 10 and, as described above, are formed by a pair
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`of arms 2a and 2b. This assures proper contact action of each
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`of the contact arms 2 with the respective IC device leads
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`without twisting by pressing force F being exerted on the
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`leads as shown in FIG. 2. Note that in the figure, number 1
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`indicates a neck of contact pin 10.
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`is
`If any of contact pins 10, arranged very closely,
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`deflected in a longitudinal direction during its contact action,
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`Page 17 of 19
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`7
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`an adjacent contact pin may contact it. Such a short circuit
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`can be prevented in that as described above contact pins 10
`are insulated from each other with each of contact arms 2
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`having the insulating means 2c formed therefore.
`This means that the electrical contacts of the IC device
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`with contact pins 10, can be made surely and securely. The
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`secure contact action of contact pins 10 free of such erro-
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`neous electrical contact between contact pins 10, allow for
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`realistically elfective arrangement of minute intervals and
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`thin wall construction of contact pins 10.
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`As described above, the IC socket having the contact pins
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`of thin wall aligned at very narrow intervals and according
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`to the present invention, has the advantage that the contact
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`action secure and can be easily formed.
`Embodiment 4
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`FIGS. 14 through 16 show a fourth embodiment for the 1C
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`socket according to the present invention. In the figures,
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`socket body 71 has numbers of grooves 71a and 71a' for
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`arrangement of contact pins 72. Each contact pins 72 is
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`formed of a ring-like contact arm 72a made up of a pair of
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`arm portions opposite to each other, and contact portion 72b
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`to make contact with a lead of an IC device. Contact portion
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`72b is to contact the lead of the IC device (not shown), a
`body 72c, and neck 72d combines contact arm 72a with
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`body 72c. Also provided are guide wall assemblies 73, each
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`of which is formed of a number of guide walls 74 for guiding
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`and insulating contact pins 72 and shaft 75 for fixing guide
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`walls 74. Further provided are posts 76 for mounting guide
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`wall assemblies 73 at comers of socket body 71.
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`In this embodiment, each of contact pins 72 is held on the
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`socket body 71 as leg 722 thereof is inserted in socket body
`71.
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`Contact arm 72a of contact pin 72 is not guided in any
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`way in this position. Each of guide wall assemblies 73 are
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`integrated of highly insulated synthetic resin or hard rubber.
`These guide wall assemblies are, is formed like a comb
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`having guide walls 74 aligned on post are as shown in FIG.
`14. Each of guide walls 74 is formed a little smaller than the
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`Virtually elliptic inside ring size of contact arrn 72a so that
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`it can be inserted in the ring. Guide walls 74 are aligned on
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`shaft 75 at the same intervals as contact pins 72 arranged on
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`socket body 71.
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`Each post 76 of socket body 71 has