U.S. patent application number 09/799203 was filed with the patent office on 2001-09-27 for cam retaining means for zif electrical connector.
Invention is credited to Hirata, Toshihisa.
Application Number | 20010024897 09/799203 |
Document ID | / |
Family ID | 18588592 |
Filed Date | 2001-09-27 |
United States Patent
Application |
20010024897 |
Kind Code |
A1 |
Hirata, Toshihisa |
September 27, 2001 |
Cam retaining means for zif electrical connector
Abstract
A electrical connector for a pin grid array package includes a
base housing for mounting a plurality of terminals in grid array
fashion, and a slide plate formed with through holes in grid array
fashion corresponding to each of the terminals and overlaid on the
upper side of the base housing. The slide plate slides between a
position in which a pin of the pin grid array package is held
adjacent to one of the terminals position and a position in which
the pin is engaged with the terminal. A cam member is inserted
through a cam opening formed in the slide plate and rotatably
supported on the base housing so that a cam surface and an opening
edge are mutually opposed. Engaging means rotatably secure the cam
member in proper axial position with respect to the base housing. A
flat surface formed on the cam surface abuts a straight edge formed
on the cam opening when the slide plate is in the position in which
the pin is engaged with the terminals.
Inventors: |
Hirata, Toshihisa;
(Yamato-shi, JP) |
Correspondence
Address: |
Robert A. Yesukevich
MOLEX INCORPORATED
2222 Wellington Court
Lisle
IL
60532
US
|
Family ID: |
18588592 |
Appl. No.: |
09/799203 |
Filed: |
March 5, 2001 |
Current U.S.
Class: |
439/342 |
Current CPC
Class: |
H05K 7/1007 20130101;
H01R 13/193 20130101 |
Class at
Publication: |
439/342 |
International
Class: |
H01R 004/50; H01R
013/625 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 14, 2000 |
JP |
69768/2000 |
Claims
What is claimed is:
1. An electrical connector for a pin grid array package comprising:
a base housing which includes an exterior side facing outwardly
from the electrical connector and an interior side forming a
generally cylindrically shaped protuberance which extends generally
transversely from the interior side, the base housing defining a
shaft which extends axially through the protuberance from the
interior side to adjacent the exterior side; a plurality of
terminals mounted on the base housing in an array which generally
corresponds to the array of the pin grid package; a slide plate
which defines a cam opening having an inside surface and through
holes corresponding to the terminals, is disposed adjacent the
interior side, and is slidably movable between a first insertion
position in which a lead pin of said pin grid array package can be
inserted into a mounting portion adjacent at least one of the
terminals and a second engagement position in which the lead pin is
engaged with at least one of the terminals; and an eccentric cam
member which includes a cam portion which defines a cam surface, a
barrel which defines a bearing bore, an engaging leg which extends
within and generally along the axis of the bearing bore, and
engaging means for engaging the bearing bore or the exterior side,
said engaging means being mounted on the engaging leg; wherein the
cam member projects into the cam opening so that the cam surface is
adjacent the inside surface, the protuberance projects into the
bearing bore to rotatably support the cam member, the engaging leg
projects into the shaft, and engaging means engages the barrel or
the exterior side to resist axial movement of the cam member
relative to the bearing bore.
2. The electrical connector of claim 1 in which the engaging leg is
strained within the barrel so as to urge said engaging means into
engagement with the barrel or the exterior side of the slide
plate.
3. The electrical connector of claim 1 in which said engaging means
includes a hook mounted on the engagement leg and a step defined by
the barrel adjacent the bearing bore.
4. The electrical connector of claim 1 in which said engaging means
includes a hook mounted on the engagement leg, the hook being
suitable to engage the intersection of the bearing bore with the
exterior surface of the base housing.
5. The electrical connector of claim 1 in which, when the slide
plate is in the second engagement position, the flat wall abuts the
straight edge to resist movement of the slide plate from the second
engagement position.
6. The electrical connector of claim 1 in which, when the slide
plate is in the first insertion position, the flat wall abuts the
straight edge to resist movement of the slide plate from the first
insertion position.
7. The electrical connector of claim 1 in which the slide plate
includes a stopper projecting from the exterior side of the slide
plate, and in which the cam member includes an operating finger
extending generally radially from cam member and generally along
the exterior surface of the slide plate to engage the stopper when
the slide plate is in the second engagement position.
8. The electrical connector of claim 1 in which the slide plate
includes a stopper projecting from the exterior side of the slide
plate, and in which the cam member includes an operating finger
extending generally radially from cam member and generally along
the exterior surface of the slide plate to engage the stopper when
the slide plate is in the first insertion position.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to an electrical
connector or socket for a pin grid array package.
DESCRIPTION OF THE RELATED ART
[0002] Typically, an electrical connector for a pin grid array
("PGA") package comprises a base housing for mounting a plurality
of terminals in grid array fashion, and a slide plate formed with
through holes in grid array fashion corresponding to the respective
terminals and overlaid on the interior side of the base housing.
The slide plate is adapted for sliding between a first insertion
position and a second engagement position. In the first insertion
position, the pins of the PGA package can be inserted adjacent to,
but without engaging, the respective terminals with relatively
small or zero insertion force. In the second engagement position,
the pins are engaged with the respective terminals.
[0003] Sliding means or actuators for the slide plate are well
known. One type of previously published sliding means includes a
cam shaft mounted along the rear edge of the base housing to pivot
the cam shaft by an operating handle provided along the side
portion of the electrical connector. See Japanese Unexamined Patent
Publication (Kokai) No. Heisei 7-142134. Another published sliding
means includes a cam member inserted through the base housing and
the slideplate and rotated by means of a flat bladed tool such as a
screw driver. See U.S. Pat. No. 6,116,936.
[0004] However, the type of sliding means in which the cam member
is inserted through the base housing and the slide plate is
susceptible to a problem known as "kickback." More specifically,
when the slide plate is in the second engagement position, a force
due to the resilience of the terminals tends to urge the slide
plate away from the base housing and, thereby, to extract the cam
member from its proper position with respect to the base housing.
Also, the kickback force tends to move the slide plate back towards
the first insertion position, thereby make the engagement between
the pins and the respective terminals relatively less stable.
Accordingly, despite the impressive achievements of earlier
inventors, there still exists a need for an improved electrical
connector.
SUMMARY OF THE INVENTION
[0005] The present invention includes a cam member having engaging
means which rotatably engage the base housing. Said engaging means
resist the tendency of kickback force to extract the cam member
from its proper operating position. Additionally, the present
invention may include a cam member having a cam surface which
includes a flat wall. When the slide plate is in a pre-determined
position, the flat wall abuts a cam opening having an inside
surface which includes a straight edge. The flat wall in acts on
cooperation with the straight edge to resist the tendency of
kickback force to move the slide plate way from the first insertion
position or the second engagement position
[0006] In a preferred aspect, the invention is an electrical
connector for a pin grid array package which includes a generally
planar base housing. The base housing has an exterior side which
faces outwardly from the electrical connector and an interior side
which faces in the opposite direction from the exterior side. The
interior side includes a generally cylindrically shaped
protuberance which extends in a direction generally transversely
from the interior side. The base housing also defines a shaft which
extends axially through the protuberance from the interior side to
a point adjacent the exterior side. Terminals are mounted on the
base housing in an array which generally corresponds to the array
of the pin grid package.
[0007] The electrical connector also includes a generally planar
slide plate which defines a cam opening having an inside surface
and through holes corresponding to the terminals. The side plate is
disposed adjacent the interior side of the base housing, and is
slidably movable between a first insertion position and a second
engagement position. In the first insertion position, a lead pin of
the pin grid array package can be inserted into a mounting portion
adjacent at least one of the terminals. In the second engagement
position, the lead pin is engaged with at least one of the
terminals
[0008] The electrical connector additionally includes an eccentric
cam member including a cam portion which defines a cam surface, a
barrel which defines a bearing bore, an engaging leg which extends
within and generally along the axis of the bearing bore, and
engaging means for engaging the bearing bore or the exterior side.
Said engaging means is mounted on the engaging leg. The cam member
projects into the cam opening so that the cam surface is adjacent
the inside surface. The protuberance projects into the bearing bore
to rotatably support the cam member. The engaging leg projects into
the shaft. Said engaging means engages the barrel or the exterior
side to resist axial movement of the cam member relative to the
bearing bore.
[0009] Preferably, the engaging leg is strained within the barrel
so as to urge said engaging means into engagement with the barrel
or the exterior side of the slide plate. Preferably, said engaging
means includes a hook mounted on the engagement leg and a step
defined by the barrel adjacent the bearing bore.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a top plan view of a embodiment of a electrical
connector for PGA package according to the present invention;
[0011] FIG. 2 is a longitudinal section of the electrical connector
depicted in FIG. 1;
[0012] FIG. 3 is an enlarged section of a mounting portion of a cam
member of a electrical connector for PGA package according to the
present invention;
[0013] FIG. 4 is a plan view of a cam member for the present
invention;
[0014] FIG. 5 is a bottom view of a cam member for the present
invention;
[0015] FIG. 6 is a top plan view of a cam member for the present
invention;
[0016] FIG. 7 is a side elevation view of a cam member for the
present invention;
[0017] FIG. 8 is a rear elevation view of a cam member for the
present invention; and
[0018] FIG. 9 is a section taken generally along line A-A of FIG.
4.
DESCRIPTION OF A PREFERRED EMBODIMENT
[0019] In a preferred embodiment, the invention is an electrical
connector 10 for a pin grid array package as shown in FIG. 1. The
electrical connector 10 comprises a generally planar and
quadrangular shaped base housing 20 and a generally planar and
quadrangular shaped slide plate 40 overlaid on the interior side of
base housing 20. A plurality of terminals 21 shown in FIG. 2 are
mounted in grid array 26 fashion on base housing 20. Tails 22
extend from each the terminals 21 and are arranged on the bottom
surface of base housing 20. A mounting portion of each of the
terminals 21 is open for receiving a pin of a PGA package (not
shown).
[0020] Slide plate 40 is formed with through holes 41 in grid array
30 fashion generally corresponding to the terminals 21. Each of two
guide projections 23 formed on opposite edges of the base housing
20 mates with one of generally L-shaped edge plates 42. The edge
plates 42 extend downwardly from the edges of the slide plate 40,
so that the slide plate 40 is adapted for sliding back and forth
along interior side 19 of base housing 20.
[0021] As shown in FIG. 1 and FIG. 3, a cam member 60 including an
indicator 66 is rotatably mounted at one end of base housing 20. A
cam opening 44 is formed in an ear piece 43 projecting from one end
of slide plate 40. A cam portion 61 of the cam member 60 projects
upwardly into the cam opening 44. A cam surface 62 and an inside
surface 45 are immediately adjacent and mutually opposed to each
other
[0022] The cam member 60 is a substantially hollow, generally
cylindrical member constructed in one piece as shown in FIGS. 4
through 9. For clarity, the end of cam member 60 attached to
indicator 66 is referred to as "the indicator end", and the
opposite end of cam member 60 is referred to as "the engagement
end". The outer, circumferential portion of the indicator end forms
a cam portion 61. A bearing bore 63 extends from the engagement end
substantially into the interior of cam member 60. The bearing bore
63 is defined by an inner, circumferential surface designated as
barrel 70. Bearing bore 63 is eccentric relative to cam portion
61.
[0023] A protuberance 24 is provided on the interior side 19 of the
base housing 20. Protuberance 24 projects into bearing bore 63 and
rotatably supports cam member 60. Preferably, protuberance 24
extends through the cam opening 44 and beyond the exterior surface
38 of the slide plate 40. The bearing bore 63 is preferably adapted
to be fitted over substantially the entire length of the
protuberance 24.
[0024] Additionally, cam member 60 is provided with engaging means
to engage the barrel 71 or the exterior side 18 of base housing 20
in order to resist axial movement of cam member 60 relative to base
housing 18. For example, engaging means 80 may include one or more
engaging legs 64 which extend along the axis of bearing bore 63
toward the engagement end of cam member 60. Preferably, engaging
legs 64 extend past an end of bearing bore bottom 63 and terminate
in an outwardly directed hook 65. Engaging legs 64 are inserted
into a shaft 71 which extends axially through protuberance 24.
Preferably, at least a portion of each of the hooks 65 extends
beyond an end of shaft 71 into a recess portion 25 formed in an
exterior side 18 of base housing 20.
[0025] It is also preferred that engaging legs 64 or hooks 65 are
resilient and, when inserted into the barrel, are slightly strained
or deformed so that this resiliency urges the hooks 65 into
engagement with the barrel 71, recess portion 25, or exterior side
18. Alternatively, engaging means 80 may include a groove or step
defined by barrel 70 adjacent bearing bore 63. In each case, hooks
65 are engaged with base housing 20 to resist any force which might
tend to move cam member 60 axially away from base housing 20.
[0026] As shown in FIGS. 4 to 9, cam member 60 is formed with a
flat wall 62a in cam surface 62. Flat wall 62a is formed at the
location in cam surface 62 which corresponds to the first insertion
position or the second engagement position of slide plate 40. FIG.
1 shows slide plate 40 in the "OPEN" or first insertion position It
should be apparent that rotating cam member 60 will place indicator
66 in the "LOCK" or second engagement position.
[0027] As shown in FIG. 1, flat wall 62a abuts straight edge 45b
with slide plate 40 in the first insertion position. As can be
readily determined from the positions of indicator 66 and guide
projections 23, FIG. 1 shows slide plate 40 in the "OPEN" or first
insertion position with slide plate 40 relatively less axially
offset from base housing 20 when slide plate 40 will be when it is
in the "LOCK" or second engagement position. However, it is
contemplated that the invention may also be utilized in an
electrical connector in which a slide plate is relatively more
axially offset in the first insertion position with respect to a
base housing, as compared to its axial offset in the second
engagement position.
[0028] In order to provide greater stability for the second
engagement position, flat wall 62 may be is formed over the entire
length in the longitudinal direction of cam portion 61.
Furthermore, indicator 66 projects radially from the upper portion
of cam portion 61 at an angle of about 90.degree. with flat wall
62a as viewed from the center of bearing bore 63. A hexagonal
recess portion 67 is formed on the upper surface of cam portion 61
so that cam member 60 can be pivotably operated directly by a
rotating tool consisting of a hexagonal bar. Of course, the recess
portion 67 may be formed to accept other well known tools.
[0029] Cam opening 44 formed in ear piece 43 of slide plate 40 is
generally quadrangular as shown in FIG. 1. Inside surface 45 of cam
opening 44 comprises two pairs of straight edges including straight
edges 45a, 45b mutually opposing in the axial direction of travel
for slide plate 40, and straight edges 45c, 45d mutually opposing
in a lateral direction as compared to the direction of travel for
slide plate 40. Straight edges 45a, 45b are spaced apart at a
distance which is about equal to the diameter of cam portion 61.
Straight edges 45c, 45d are spaced apart at a distance which is
significantly greater than the diameter of cam portion 61 in order
to permit free movement in view of the eccentricity of cam member
60.
[0030] Adjacent cam opening 44, stoppers 46a, 46b are adapted to
alternately engage indicator 66. Stopper 46a is located near the
intersection of straight edge 45a with straight edge 45c. Stopper
46b is located near the intersection of straight edge 45a with
straight edge 45c. Indicator 66 extends generally along the upper
surface of ear piece 43 at a distance from the slide plate exterior
side 38 which results in engagement with the stoppers 46a, 46b.
[0031] FIG. 1 depicts the relation of slide plate 40 to base
housing 20 when both are in the first insertion position. At that
time, indicator 66 is pointed toward the legend "OPEN" which is
provided on the surface of base housing 20, and is engaged with
stopper 46a. Flat wall 62a is approximately parallel to and engaged
with straight edge 45b.
[0032] When cam member 60 is rotated to the position depicted in
FIG. 1, the engagement between flat wall 62a of cam surface 62 and
straight edge 45b of inside surface edge 45 transmits a clicking
feeling to a human operator. After the engagement, cam member 60 is
at least partially protected from unintended rotation by vibration,
accident or the like. This engagement also provides some protection
against over-rotation of can member 60 in the counter clockwise
direction.
[0033] With the slide plate 40 in the first insertion position, the
PGA package to be connected may be mounted on slide plate 40 with
the lead pins of the PGA package extending toward the base housing
20. In this manner, the lead pins can be inserted into the mounting
portion of terminals 21 with zero insertion force or insertion
force close to zero.
[0034] After the PGA package is mounted, cam member 60 is pivoted
at 180.degree. in the clockwise direction to complete the
connection. Under the influence of rotating cam member 60, slide
plate 40 slides along base housing 20 in the direction of greater
axial offset relative to base housing 40, the lead pins inserted
moved to the second position of engagement.
[0035] The clockwise rotation of cam member 60 is interrupted when
indicator 66 engages with stopper 46b. At that time, flat wall 62a
of cam surface 62 is generally parallel to and engaged with
straight edge 45a. The engagement transmits another clicking
feeling as a signal to a human operator.
[0036] When the lead pins are moved to the second position of
engagement with terminals 21, the resilience of terminals 21 exerts
a kickback force on slide plate 40 via the lead pins. In fact, this
kickback force may cause the cam members of conventional electrical
connectors to rotate and their slide plates to move from the second
engagement position. However, with the present invention, flat wall
62a is generally parallel straight edge 45a,so that it the
electrical connector 10 of the present invention is relatively
immune to the adverse effects of kickback force.
[0037] Although the present invention has been illustrated and
described with respect to a preferred embodiment, it will be
understood by those skilled in the art that the foregoing and
various other changes, omissions and additions may be made to the
preferred embodiment without departing from the spirit and scope of
the present invention. The present invention is not be understood
as limited to the preferred embodiment set out above but, rather,
includes all possible embodiments which can be embodied within a
scope encompassed and equivalents thereof with respect to the
features set out in the appended claims.
* * * * *