U.S. patent application number 11/261586 was filed with the patent office on 2007-05-03 for pusher of ic chip handler.
This patent application is currently assigned to DAYTONA CONTROL CO., LTD.. Invention is credited to Shintaro Hayashi, Mitsuo Koizumi, Osamu Urakawa.
Application Number | 20070099447 11/261586 |
Document ID | / |
Family ID | 37996990 |
Filed Date | 2007-05-03 |
United States Patent
Application |
20070099447 |
Kind Code |
A1 |
Hayashi; Shintaro ; et
al. |
May 3, 2007 |
PUSHER OF IC CHIP HANDLER
Abstract
A pusher of an IC chip handler has a pusher frame which is
attached to a pusher main body to be driven by the IC chip handler
and a plurality of pusher heads attached to the pusher frame. Each
of the pusher heads comprises a holder which is held by the pusher
frame. At least one spring post is freely protruded outward from
the inside of the holder, and a compression spring has one end
arranged under pressure to a spring receiving portion of the spring
post. A spring push plate arranges the compression spring to the
spring receiving portion of the spring post under pressure, and an
adjusting member adjusts a compression force of the compression
spring. A device holding unit is attached to an end of the spring
post protruded outside of the holder.
Inventors: |
Hayashi; Shintaro;
(Yokohama-shi, JP) ; Urakawa; Osamu;
(Yokohama-shi, JP) ; Koizumi; Mitsuo;
(Fukushima-shi, JP) |
Correspondence
Address: |
NIXON & VANDERHYE, PC
901 NORTH GLEBE ROAD, 11TH FLOOR
ARLINGTON
VA
22203
US
|
Assignee: |
DAYTONA CONTROL CO., LTD.
Yokohama-shi
JP
|
Family ID: |
37996990 |
Appl. No.: |
11/261586 |
Filed: |
October 31, 2005 |
Current U.S.
Class: |
439/73 |
Current CPC
Class: |
G01R 31/2893
20130101 |
Class at
Publication: |
439/073 |
International
Class: |
H01R 12/00 20060101
H01R012/00 |
Claims
1. A pusher of an IC chip handler, comprising: a holder which is
held at an end of a pusher main body to be driven by an IC handler;
at least one spring post which is freely protruded outward from
inside of the holder; a compression spring with one end is arranged
under pressure to a spring receiving portion of the spring post; a
spring push plate which arranges the compression spring to the
spring receiving portion of the spring post under pressure;
adjusting means for adjusting a compression force of the
compression spring; and a device holding unit attached to an end of
the spring post protruded outside of the holder. wherein the
adjusting means includes an adjusting screw which adjusts a
distance between the spring push plate and the holder, thereby
adjusting a compression distance of the spring, a scale formed on
the spring push plate, and a pointer provided on the screw for
indicating a rotation position of the adjusting screw in relation
to the scale.
2-3. (canceled)
4. A pusher of an IC chip handler, having a pusher frame which is
attached to a pusher main body to be driven by an IC handler, and a
plurality of pusher heads which are attached to the pusher frame,
wherein each of the pusher heads comprises: a holder which is held
by the pusher head; at least one spring post which is freely
protruded outward from inside of the holder; a compression spring
whose one end is arranged under pressure to a spring receiving
portion of the spring post; a spring push plate which arranges the
compression spring to the spring receiving portion of the spring
post under pressure; adjusting means for adjusting a compression
force of the compression spring; and a device holding unit attached
to an end of the spring post protruded outside of the holder,
wherein the adjusting means includes an adjusting screw which
adjusts a distance between the spring push plate and the holder,
thereby adjusting a compression distance of the spring, a scale
formed on the spring push plate, and a pointer provided on the
screw for indicating a rotation position of the adjusting screw in
relation to the scale.
5-6. (canceled)
7. A pusher of an IC chip handler according to claim 1, wherein two
spring posts are protruded outward from the holder; two compression
springs are arranged between the spring push plate and the two
spring posts, the elasticity of the two springs being set to apply
substantially the same compression force to the two springs posts,
respectively; and the device holding plate is fixed to ends of the
two spring posts protruded outward from the holder and is provided
with a device suction portion to hold the IC chip thereon.
8. A pusher of an IC chip handler according to claim 4, wherein
each of the pusher heads comprises two spring posts protruded
outward from the holder; and two compression springs arranged
between the spring push plate and the two spring posts, the
elasticity of the two springs being set to apply substantially the
same compression force to the two spring posts, respectively; and
wherein the device holding plate is fixed to ends of the two spring
posts protruded outward from the holder, the device holding plate
being provided with a device suction portion to hold the IC chip
thereon, respectively.
9. A pusher of an IC chip handler, comprising: a holder held at an
end of a pusher main body to be driven by an IC handler; at least
one spring post freely protruded outward from inside of the holder;
a compression spring having one end arranged under pressure to a
spring receiving portion of the spring post; a spring push plate
arranging the compression spring to the spring receiving portion of
the spring post under pressure; an adjusting assembly that adjusts
a compression force of the compression spring; and a device holding
unit attached to an end of the spring post protruded outside of the
holder, wherein the adjusting assembly includes an adjusting screw
which adjusts a distance between the spring push plate and the
holder, thereby adjusting a compression distance of the spring, a
scale formed on the spring push plate, and a pointer provided on
the screw for indicating a rotation position of the adjusting screw
in relation to the scale.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a pusher of an IC chip
handler, and more specifically, to a pusher for testing a plurality
of IC chips one by one or simultaneously.
[0003] 2. Description of the Related Art
[0004] A plurality of pushers are used for testing a plurality of
IC chips simultaneously. In this case, the plurality of IC chips to
be tested simultaneously are selected from, for example, a single
production lot, and therefore, the external dimensions thereof such
as the thickness must have been formed evenly. However in practice,
these IC chips have production errors in, for example, the
thickness thereof. Further, as a terminal pin of an IC chip and a
test pin of a socket, various kinds of terminals such as a solder
ball terminal, a film-shaped terminal, a spring-shaped terminal,
and a pogo pin terminal are employed. The height of these pins also
has errors from a set value owing to production errors or changes
by aging. Furthermore, a leaf spring or a coil spring, etc. is
employed as a test pin of a socket to be set to contact terminal
pins at a predetermined pressure when they are arranged under
pressure. However, the elasticity of these springs also varies, and
changes by aging, which leads to incomplete contact.
[0005] In general, when an IC chip is set onto a socket, a pusher
goes down a preset distance and stops thereat. If the dimensions of
each IC chip and terminal pin are normal, the terminal pin of the
IC chip normally contacts the test pin at the test device side by
the pusher at this position, and test is performed. In this case,
for example, if the thickness of the IC chip is larger than a set
range, the IC chip is pushed more than required by the pusher when
the pusher goes down a preset distance, so that the terminal pin of
the IC chip and the test pin of the socket may be deformed or
damaged. In the case where the IC chip is thinner than the set
value, a pushing pressure of the IC chip to the socket by the
pusher becomes insufficient if the lowering distance of the pusher
is the preset value, so that test cannot be performed normally
owing to incomplete contact of the terminal pin.
[0006] Further, there is a case where a plurality of IC chips are
tested simultaneously by use of a plurality of pushers. In this
case, the lowering distance of the pusher corresponding to each
socket is set evenly. Therefore, if there is an error in the
dimensions of the IC chip and the terminal pin, the IC chip is
pushed more than the standard value, for example, when the IC chip
is thicker than the set value, so that nonconformities such as
breakage may occur. When the IC chip is thinner than the set value,
test results may become incorrect owing to incomplete contact of
the terminal due to insufficient pressure setting.
[0007] In order to solve these problems with the prior art, various
countermeasures have been made. However, IC chips to be tested are
various, and testing costs will become high if pushers
corresponding to these various specifications of the IC chips are
to be prepared, which is not practical. Therefore, the realization
of a pusher which can be applied in common to IC chips of various
specifications has been required conventionally.
BRIEF SUMMARY OF THE INVENTION
[0008] According to an aspect of the present invention, there is
provided a pusher of an IC chip handler, comprising: a holder which
is held at an end of a pusher main body to be driven by an IC
handler; at least one spring post which is freely protruded outward
from the inside of the holder; a compression spring whose one end
is arranged under pressure to a spring receiving portion of the
spring post; a spring push plate which arranges the compression
spring to the spring receiving portion of the spring post under
pressure; adjusting means for adjusting a compression force of the
compression spring; and a device holding unit attached to an end of
the spring post protruded to the outside of the holder.
[0009] According to the present invention, it is possible to easily
adjust a pushing force at the moment when an IC chip attached to
the front end of the pusher is pushed against a socket during
testing. Further, it is possible to absorb the differences of
compression distances due to differences of thickness of the IC
chips or devices to be tested when a plurality of IC chips are
tested simultaneously. As a consequence, it is possible to provide
a pusher of an IC chip handler, which can be applied in common to
IC chips of various specifications and enables to attain a simple
structure and to reduce testing costs, and further to attain
precise testing results.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0010] FIG. 1 is a cross sectional view showing a pusher according
to an embodiment of the present invention;
[0011] FIG. 2 is a plan view showing a device pushing force
adjusting unit;
[0012] FIG. 3 is a schematic block diagram simply showing an entire
configuration of an IC chip handler to which the pusher shown in
FIG. 1 is attached;
[0013] FIG. 4 is a graph showing a relation between a compression
distance and a compression pressure of a compression spring shown
in FIG. 1;
[0014] FIG. 5 is a cross sectional view showing a state before
absorbing an error in IC chip thickness at the time of testing in
correspondence to FIG. 3; and
[0015] FIG. 6 is a cross sectional view showing a state in which an
error in IC chip thickness has been absorbed in FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
[0016] In FIG. 1, a holder 12 of a cylindrical shape with a bottom
as one of components configuring a pusher head 10 is held fixedly
to an end of an arm head 11 (shown in FIG. 3) attached to a pusher
arm to be driven by an IC handler. A circular hole 12B is formed at
the central portion of a bottom 12A of the holder 12, and the
circular hole 12B is blocked by a bottom plate 13 fixed to the
outside of the bottom 12A with a plurality of screws 13A. The
bottom plate 13 has a plurality of conical funnel shaped holes 13B
formed from the inside thereof to the outside. Two conical funnel
shaped holes 13B are formed in the bottom plate 13 in this
embodiment, but three or more holes 13B may be formed.
[0017] Spring posts 14, 15 are inserted to the conical-shaped
portions of the funnel-shaped holes 13B. The spring posts 14, 15
have conical-shaped portions corresponding to the conical shape
holes 13B, and the ends thereof are protruded from the under
surface of the bottom plate 13. Spring receiving portions 14A, 15A
are formed in the bottoms of the conical-shaped portions of the
spring posts 14, 15, and one ends of compression springs 16, 17 are
engaged to the receiving portions 14A, 15A, respectively. The other
end of each of the compression springs 16, 17 is arranged to a
spring push plate 18 under pressure. The spring push plate 18 is
fixed rotatably to the upper portion of a spring force adjusting
screw 19 screwed into the central portion of the bottom plate 13.
For example, a slot 19B is formed in a head 19A of the spring force
adjusting screw 19, and a flange 18A is formed in the spring push
plate 18 so as to slide in the slot 19B.
[0018] A disk-shaped scale plate 20 is engaged and fixed to a
concave portion of the upper surface of the spring push plate 18,
as shown in FIG. 2. On the inner diameter portion along the head of
the screw 19 of the scale plate 20, a scale 20A for adjusting the
spring force of the springs 16, 17 is inscribed. On the other hand,
a pointer 19C is inscribed on the screw head 19A, and the pointer
19C moves along the scale 20A by the rotation of the screw 19 and
displays the spring force or the total compression pressure of the
springs 16, 17. Meanwhile, the elasticity of the springs 16, 17 is
so set as to apply the substantially same compression force to the
spring posts 14, 15 respectively.
[0019] The ends of the spring posts 14, 15 protruded from the under
surface of the bottom plate 13 attached as a part of the holder 12
are screwed and fixed into a device holding plate 22. A device
suction portion 22A is formed on the under surface of the device
holding plate 22. In the device suction portion 22A, a vacuum
suction hole which is coupled to, for example, a vacuum pump (not
shown) provided in the handler via the pusher main body 11 is
formed. At the time of testing, a device to be tested, for example,
an IC chip 24 is sucked to the device suction portion 22A, and
transferred to the socket at a test position. Meanwhile, there is
described a case in which the terminals of the IC chip 24 are a
plurality of solder balls 24A.
[0020] FIG. 3 is a block diagram schematically showing a
configuration of a handler having two pieces of the pusher shown in
FIG. 1 and a tester to be used for testing IC chips in connection
with the handler. In FIG. 3, a pusher arm 32 of a handler 31 is
configured to be driven in the vertical direction M at testing. A
plurality of pusher heads, herein, two pusher heads 10A, 10B are
mounted on the pusher arm 32 via an arm head 11. IC chips 24A, 24B
are sucked to the pusher heads 10A, 10B, respectively.
[0021] FIG. 3 shows a configuration in the case of testing the IC
chips 24A, 24B by use of the handler 31 and a tester 34. A tester
head 35 is attached to the tester 34, and a socket holding plate 36
is fixed onto the tester head 35. Pogo pin type sockets 37A, 37B
are attached onto the socket holding plate 36, and the IC chips
24A, 24B held by the pusher heads 10A, 10B are pushed to the
sockets 37A, 37B. A plurality of pogo pins 38 are arranged
two-dimensionally on the socket 37A such that the pin heads
protruding from the socket 37A directly contact solder balls as
terminal pins of the IC chip 24A. Each of the solder balls
protrudes by a predetermined dimension from the under surface of
the IC chip 24A, and the protrusion height may have an error more
or less. The pogo pin 38 is of an elastic structure where the pin
head thereof is instructed by a spring, and it is configured such
that the height error of the solder ball is absorbed by the spring
structure of the pogo pin 38. The other socket 37B is configured in
the same manner as described above. The configuration of the pogo
pin 38 is known to those skilled in the art, and therefore, further
explanations thereof are omitted.
[0022] The pusher arm 32 is arranged, for example, at level, and
the production dimensions of the arm head 11 and the pusher heads
10A, 10B attached to the under surface of the arm head 11 are
precisely set. Thus, the dimension from the under surface of the
pusher arm 32 to the end of the pusher head 10A is substantially
the same as the dimension from the under surface of the pusher arm
32 to the end of the pusher head 10B at the level line L. In the
same manner, the socket holding plate 36 attached onto the tester
head 35 is arranged at level, and the distances from the upper
surface of the socket holding plate 36 to the pin heads of the
respective pogo pins 38 of the sockets 37A, 37B arranged thereon
are set so as to be substantially the same.
[0023] Accordingly, if the thickness of the IC chip 24A to the base
of the solder balls is substantially the same as the thickness of
the IC chip 24B, the IC chip 24B is pushed to the socket 37B at
substantially the same time as the IC chip 24A is pushed to the
socket 37A by the lowering of the pusher arm 32 during testing, and
the test by the tester 34 is performed to the IC chips 24A, 24B at
substantially the same time.
[0024] However, as shown in FIG. 5, for example, it is assumed that
the IC chip 24A is, for example, 1 mm thicker than the IC chip 24B.
Then, at the moment when the IC chip 24A is contacted to the socket
37A during testing, the IC chip 24B is still 1 mm before the socket
37B. The distance between the tip of the IC chip 24B and the socked
37B is denoted as H, in the figure. Accordingly, the pusher arm 32
is lowered further 1 mm or H mm, until the IC chip 24B is contacted
to the socket 37B. At this moment, the IC chip 24A is pushed toward
the socket 37B further from the first contact position. This state
will be described and is shown in FIG. 6.
[0025] Herein, the comprehensive compression force of springs of
the pogo pins 38 arranged two-dimensionally in the socket 37A is
set larger than the total compression force of the springs (such as
those 16, 17 shown in FIG. 1) that push downward the IC chip 24A in
the pusher head 10A. For example, when the pusher head 10A is of
the configuration shown in FIG. 1, the total compression force of
the pusher head 10A becomes the total of the compression forces of
the two springs 16, 17.
[0026] Consequently, when the pusher arm 32 goes down further 1 mm
or from the position where the IC chip 24A contacts the socket 37A,
the springs 16, 17 shown in FIG. 1 are compressed further 1 mm or H
mm. In this state, the IC chip 24B is also pushed to the socket
37B, and, simultaneous test of the IC chips 24A, 24B becomes
possible in this state, as shown in FIG. 6. However, in order to
increase the reliability of testing results, it is desirable to, in
practice, perform test at a position to which the pusher arm 32 is
lowered further by a predetermined distance.
[0027] Herein, with reference to FIG. 4, an explanation will be
given for the spring characteristic of the spring 16 shown in, for
example, FIG. 1, in other words, the relation between the
compression distance and the compression pressure at the time when
the spring 16 is compressed, and in connection therewith, the
operation of the spring force adjusting screw 19 shown in FIG. 1
will be explained. The spring 16 is a coil spring, and when the
compression pressure thereof is 0 (g), the compression distance
thereof is also 0 (mm). The spring 16 is set so as to be compressed
1 mm when pushed with a force of 1 g, for example. Accordingly, the
more the pushing force increases, the more the compression distance
increases along the straight line C. The spring 17 is formed in
substantially the same manner as in the spring 16.
[0028] Hereinafter, the spring force adjusting screw 19 shown in
FIG. 1 will be explained with reference to FIG. 4. Herein, since,
in FIG. 1, two springs 16, 17 are used to one pusher head 10, the
inclination of the spring characteristic curve C in FIG. 4 becomes
half in practice. However, for convenience of explanations, it is
assumed that FIG. 4 shows the comprehensive spring characteristic
of the two springs 16, 17. In FIG. 1, when the springs 16, 17 are
assembled between the spring push plate 18 and the spring posts 14,
15, the springs are compressed by only a compression distance Ds in
FIG. 4 by turning the spring force adjusting screw 19. In this
manner, the IC chip 24 is pushed downward with a pressure Ps by the
springs 16, 17. The pressure Ps is set to such a value that, for
example, in the case of the pusher head 10A in FIG. 3, the solder
balls as the terminal pins of the IC chip 24A are pushed to the
pogo pins 38 as the test pins of the socket 37A with an appropriate
pressure, and a preferable contact is kept therebetween and no
disadvantageous influence is given to the IC chip 24A. Further, the
more the spring force adjusting screw 19 is fastened, the more the
compression distance increases, and concurrently, the more the
compression pressure becomes. At the compression distance Ds + D
shown in FIG. 4, the compression pressure reaches an allowable
maximum pressure Pm. At the allowable value Pm or less, the
compression pressure is set such that there occurs no trouble such
as breakage of the IC chip 24A by being pushed at the socket
37A.
[0029] For example, as shown in FIG. 2, the scale plate 20 is
formed on the upper surface of the spring push plate 18, and the
pressure pointer 19C is formed on the head portion of the spring
force adjusting screw 19. Therefore, by entering the allowable
value Pm on the scale plate 20, it is possible to set the
compression pressure precisely by rotating the screw 19, and to
easily check the allowable value Pm by visual inspection.
[0030] As described previously, it is assumed that, for example,
the initial compression pressures of the respective compression
springs of the pusher heads 10A, 10B are set to Ps. Herein,
assuming that the IC chip 24A as the device to be tested is 1 mm
thicker than the IC chip 24B, the spring of the pusher head 10A is
compressed 1 mm more than the spring of the pusher head 10B.
Accordingly, when the compression distance of the pusher head 10B
at the time of an actual test is at point C1 on the curve C in FIG.
4, the compression distance of the pusher head 10A is at point C2
that is 1 mm more than the point Cl.
[0031] In the pusher head 10 of the embodiment shown in FIG. 1, the
configuration thereof is made so as to hold the IC chip 24 as the
device to be tested by use of the two springs 16, 17. However, it
is desirable that the IC chip 24 is held at level precisely, and
the IC chip 24 is held at least at three points, for example, at
four points. Thus, it is desirable that four springs are used to
one pusher head in the same configuration as shown in FIG. 1.
[0032] Further, in the embodiment shown in FIG. 3, an explanation
has been given for the case where two pusher heads 10A, 10B are
attached onto one pusher arm 32, and thereby two IC chips 24A, 24B
are tested at the same time. However, further more pusher heads may
be attached to the pusher arm 32 via the arm head 11 to test more
IC chips simultaneously.
[0033] Furthermore, in the embodiment in FIG. 3, the tester 34
including the sockets 37A, 37B is of substantially the same
configuration as that of a commercially available tester. In
addition, the arm head 11 may be applied to not only the pusher arm
32 of the handler 31, but also to many commercially available
handlers merely through modification of the attachment structure
thereof. Further, a plurality of pusher heads may be mounted
directly to the pusher arm without using the arm head 11.
Accordingly, the pusher according to the present invention is a
general purpose pusher, and the application thereof is extremely
wide, thereby reducing users' testing costs remarkably.
[0034] According to the present invention, it is possible to easily
adjust the pushing force at the moment when the IC chip attached to
the end of the pusher is pushed to the socket during testing. As a
consequence, it is possible to provide a pusher of an IC chip
handler, which can be applied in common to IC chips of various
specifications and enables to attain a simple structure and to
reduce testing costs, and further to attain precise testing
results.
[0035] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
* * * * *