U.S. patent application number 12/084940 was filed with the patent office on 2009-05-14 for abrasive waterjet type cutting apparatus.
This patent application is currently assigned to TOWA CORPORATION. Invention is credited to Kazuyuki Kishimoto, Yasuyuki Ueyama.
Application Number | 20090124178 12/084940 |
Document ID | / |
Family ID | 38522231 |
Filed Date | 2009-05-14 |
United States Patent
Application |
20090124178 |
Kind Code |
A1 |
Ueyama; Yasuyuki ; et
al. |
May 14, 2009 |
Abrasive Waterjet Type Cutting Apparatus
Abstract
A cutting apparatus includes a fixing table where a position of
an encapsulated body that is an example of a workpiece is fixed,
and a nozzle from which an abrasive waterjet containing abrasive
grains for cutting the encapsulated body is sprayed out. The fixing
table includes a plurality of protrusions and a plurality of bases.
Each of the plurality of protrusions is partitioned by a groove so
as to correspond to a plurality of package products subsequent to
cutting of the encapsulated body, and includes a through hole to
draw in by suction the encapsulated body or one of the plurality of
package products. Each of the plurality of bases links protrusions
together aligned along at least one direction among the plurality
of protrusions. A region of the plurality of protrusions or the
plurality of bases against which the abrasive waterjet collides is
formed of a material higher in hardness than the abrasive
grains.
Inventors: |
Ueyama; Yasuyuki; (Kyoto,
JP) ; Kishimoto; Kazuyuki; (Kyoto, JP) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
TOWA CORPORATION
Kyoto-shi, Kyoto
JP
|
Family ID: |
38522231 |
Appl. No.: |
12/084940 |
Filed: |
December 28, 2006 |
PCT Filed: |
December 28, 2006 |
PCT NO: |
PCT/JP2006/326208 |
371 Date: |
May 14, 2008 |
Current U.S.
Class: |
451/91 |
Current CPC
Class: |
B24C 1/045 20130101;
B26F 3/008 20130101 |
Class at
Publication: |
451/91 |
International
Class: |
B24C 5/00 20060101
B24C005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 20, 2006 |
JP |
2006-076281 |
Claims
1. A cutting apparatus comprising: a fixing table where a position
of a workpiece is fixed, and a nozzle from which an abrasive
waterjet containing abrasive grains for cutting said workpiece is
sprayed out, wherein said fixing table comprises a plurality of
protrusions, each partitioned by a groove so as to correspond to a
plurality of package products subsequent to cutting of said
workpiece, and including a through hole to draw in by suction said
workpiece or one of said plurality of package products, a plurality
of bases, each linking protrusions together aligned along at least
one direction among said plurality of protrusions, and a plurality
of protection members, each placed in a detachable manner on an
upper surface of said plurality of bases so as to traverse said
plurality of bases in plan view, a region of said plurality of
protrusions and said plurality of bases against which said abrasive
waterjet collides being formed of a material higher in hardness
than said abrasive grains.
2. The cutting apparatus according to claim 1, further comprising a
mount member provided between said workpiece or said plurality of
package products and said plurality of protrusions, and on which
said workpiece or said package products are placed, said mount
member including a material lower in hardness than said abrasive
grains.
3. A cutting apparatus comprising: a fixing table where a position
of a workpiece is fixed, and a nozzle from which an abrasive
waterjet containing abrasive grains for cutting said workpiece is
sprayed out, wherein said fixing table comprises a plurality of
protrusions, each partitioned by a groove so as to correspond to a
plurality of package products subsequent to cutting of said
workpiece, and including a through hole to draw in by suction said
workpiece or one of said plurality of package products, a plurality
of bases, each linking protrusions together aligned along at least
one direction among said plurality of protrusions, said cutting
apparatus further comprising a container in which said fixing table
is placed in an interior cavity, and into which liquid (91) is
poured into the interior cavity, said fixing table being immersed
in said liquid so that said abrasive waterjet does not achieve
direct collision with said plurality of protrusions and said
plurality of bases but achieves direct collision with said
workpiece in said container.
4. The cutting apparatus according to claim 3, further comprising a
mount member provided between said workpiece or said plurality of
package products and said plurality of protrusions, and on which
said workpiece or said package products are placed, said mount
member including a material lower in hardness than said abrasive
grains.
Description
TECHNICAL FIELD
[0001] The present invention relates to a cutting apparatus having
a nozzle from which high-pressure water containing abrasive grains,
i.e. an abrasive waterjet, is sprayed out to cut or work on a
workpiece attached to a fixing table.
BACKGROUND ART
[0002] Conventionally, the method of cutting or working on a
workpiece by means of an abrasive waterjet is known. In this
method, high-pressure fluid (waterjet) containing an abrasive
substance is applied with pressure to eject the high-pressure fluid
from the nozzle in order to cut or work on a workpiece. This method
is disclosed in, for example, Japanese Patent Laying-Open No.
2000-767 on pages 2-4 and FIGS. 1-4.
[0003] In the working method by means of an abrasive waterjet
disclosed in the aforementioned Japanese Patent Laying-Open No.
2000-767, garnet, silica sand, cast steel, grit or the like is
employed for the abrasive substance (abrasive grains). The abrasive
substance in a wet state is delivered from an abrasive substance
tank into the mixing chamber of the nozzle head via a supply pipe
and supply inlet. At this stage, the abrasive substance is fed into
the mixing chamber by high-pressure air generated by a compressor.
Then, the abrasive substance is mixed with high-pressure water in
the mixing chamber.
[0004] As a result, the abrasive waterjet is sprayed out from the
nozzle. The abrasive waterjet passes through grooves in a table on
which a workpiece is supported (fixing table) to be collected by a
catcher. Subsequently, the abrasive substance is collected through
a sieve and returned to the abrasive substance tank in the wet
state to be used again. This technique is shown in FIGS. 1 and 4 in
Japanese Patent Laying-Open No. 2000-767.
[0005] In recent years, the cutting apparatus set forth above is
used to cut an encapsulated body of a semiconductor chip that is an
example of a workpiece. Specifically, the aforementioned cutting
apparatus is used to cut an encapsulated body (substrate) in which
chip-like components (semiconductor chips and the like) mounted on
a circuit board are encapsulated all together in resin, along
respective orthogonal cutting lines corresponding to a lattice
pattern. For this cutting operation, a cutting position of high
accuracy and a cutting width of approximately 200 .mu.m are
required.
[0006] When a conventional cutting apparatus is employed, the
encapsulated body is first placed on a table having grooves, and
cut along cutting lines extending in one direction. Then, the
encapsulated body will be cut along cutting lines extending in
another direction orthogonal to the one direction. In the cutting
method employing such a cutting apparatus, the table having grooves
extending in the one direction is replaced, after the encapsulated
body is cut along cutting lines in one direction, with another
table having grooves extending in a direction differing by
90.degree. from the grooves of the previous table extending in the
one direction. Thereafter, the encapsulated body is aligned at a
predetermined position on the other table, and then cut along the
cutting line extending in the other direction.
[0007] The reason why the tables have to be replaced is to avoid
wear on the base portion of the table (fixing table) on which the
encapsulated body qualified as the object of cutting is supported.
Specifically, the purpose is to allow the abrasive waterjet to pass
through the grooves formed in the table without being brought into
contact with the base. This is described in the publication of
Japanese Patent Laying-Open No. 2000-767 with reference to FIG.
4.
[0008] Thus, the abrasive waterjet cuts the workpiece (encapsulated
body) secured on a different table, and then passes through the
grooves in the different table without establishing contact
therewith to be collected by a catcher.
[0009] According to the cutting method employing this conventional
cutting apparatus, two tables are necessary, which will increase
the cost for the cutting apparatus. Furthermore, alignment of the
encapsulated body relative to one table is required, in addition to
the alignment of the encapsulated body relative to the different
table. Accordingly, the efficiency of the cutting operation will be
degraded. There is also the possibility of degradation in the
cutting accuracy based on the cutting position, angle, and the
like.
[0010] Patent Document 1: Japanese Patent Laying-Open No. 2000-767
(pages 2-4 and FIGS. 1-4)
DISCLOSURE OF THE INVENTION
Problem to be Solved by the Invention
[0011] To solve the problem encountered in the cutting apparatus
set forth above, specifically in order to cut an encapsulated body
using only one table (fixing table) while preventing contact of the
water containing abrasive grains with the base, the inventors of
the present invention developed a cutting apparatus that can cut an
encapsulated body under a state where a protection member is
provided so as to cover the base of the table. This cutting table
is disclosed in, for example, Japanese Patent Application No.
2005-276904 that was not yet published at the time of filing the
present application. Japanese Patent Application No. 2005-276904 is
incorporated herein by reference in the present application.
[0012] In accordance with this cutting apparatus, an encapsulated
body is cut along two directions crossing each other using the same
fixing table without wear on the fixing table. This is described in
Japanese Patent Application No. 2005-276904 with reference to FIG.
6. In other words, this cutting apparatus is dispensed with
preparing a plurality of fixing tables, exchanging fixing tables,
and alignment of the encapsulated body a plurality of times in the
case where an encapsulated body is to be cut along two crossing
directions.
[0013] However, it was found that the cutting apparatus set forth
above had a problem different from the aforementioned problems. For
the sake of understanding the problem, FIG. 7(A) in Japanese Patent
Application No. 2005-276904 is to be referred to.
[0014] The cutting apparatus set forth above includes a fixing
table. The fixing table includes a plurality of protrusions. Each
of the plurality of protrusions has a through hole extending in the
axial direction and a recess at the tip. At the fixing table, an
encapsulated body adheres to the tip of the protrusions by a
suction action sequentially through the through holes and recesses.
Accordingly, the encapsulated body is secured by the fixing table,
i.e. secured to each protrusion and the frame provided around the
protrusions. Under this state, an abrasive waterjet is sprayed out
at high pressure from a nozzle. Thus, the encapsulated body is cut
along a cutting line in one direction (X direction) among the
cutting lines extending in two crossing directions.
[0015] According to a cutting method employing the cutting
apparatus set forth above, high-pressure water containing abrasive
grains used in cutting will collide against the protection member,
but not against the upper surface of the base in the groove.
[0016] The pressure (jet force) of the high-pressure water
(abrasive waterjet) will hardly be reduced by the collision with
the protection member. In other words, the high-pressure water
(abrasive waterjet) is blasted back from the upper surface of the
protection member without reduction in pressure. This high-pressure
water will collide against the side face of the protrusion provided
adjacent to the protection member. The pressure of the
high-pressure water at this stage is substantially equal to the
pressure of the high-pressure water immediately before collision
with the protection member.
[0017] The protection member is formed of a material higher in
hardness than the abrasive grains so as to withstand the pressure
of the high-pressure water. However, the protrusion set forth above
is not formed of such a material. Therefore, the side face of the
protrusion will be abraded significantly.
[0018] Furthermore, the high-pressure water will be more or less
dispersed in every direction without colliding against the
protection member when the cutting operation of the encapsulated
body is terminated. The scattering high-pressure water will cause
wear on the protrusion and frame member located close to the
protection member.
[0019] If the protrusion and frame member are partially worn, the
encapsulated body cannot be secured reliably. Therefore, the
protrusion and frame member will have to be exchanged with another
protrusion and frame member. In this case, all the components of
the fixing table, including the protrusion and frame member that
may be continually used, must be exchanged. If the frequency of
exchanging all the components of the fixing table is increased, the
cost for exchanging all the components of the fixing table will
become higher than the cost of the protection member.
[0020] In view of the foregoing problems, an object of the present
invention is to provide an abrasive waterjet type cutting apparatus
that can prevent wear on a base, as well as wear on sections other
than the base of a fixing table for holding an encapsulated
body.
Means for Solving the Problems
[0021] According to an aspect of the present invention, a cutting
apparatus includes a fixing table where a position of a workpiece
is fixed, and a nozzle from which an abrasive waterjet containing
abrasive grains for cutting the workpiece is sprayed out. The
fixing table includes a plurality of protrusions and a plurality of
bases. Each of the plurality of protrusions is partitioned by a
groove so as to correspond to a plurality of package products
subsequent to the cutting of the workpiece, and includes a through
hole for drawing in the workpiece or one of the plurality of
package products. Each of the plurality of bases links protrusions
aligned along at least one direction together among the plurality
of protrusions. A region of the plurality of protrusions and the
plurality of bases against which the abrasive waterjet collides is
formed of a material higher in hardness than the abrasive
grains.
[0022] According to another aspect of the present invention, a
cutting apparatus includes a fixing table where a position of a
workpiece is fixed, and a nozzle from which an abrasive waterjet
containing abrasive grains for cutting the workpiece is sprayed
out. The fixing table includes a plurality of protrusions and a
plurality of bases. Each of the plurality of protrusions is
partitioned by a groove so as to correspond to a plurality of
package products subsequent to the cutting of the workpiece, and
includes a through hole for drawing in the workpiece or one of the
plurality of package products. Each of the plurality of bases links
protrusions aligned along at least one direction together among the
plurality of protrusions. The cutting apparatus further includes a
container in which the fixing table is placed in an interior cavity
and into which liquid is poured into the interior cavity. The
fixing table is immersed in the liquid to avoid direct collision
with the abrasive waterjet in the container.
[0023] The cutting apparatus of the aspects set forth above of the
present invention preferably includes a mount member provided
between the workpiece or plurality of package products and the
plurality of protrusions, and on which the workpiece or each of the
plurality of package products is placed. In this case, the mount
member preferably contains a material lower in hardness than the
abrasive grains.
[0024] The features of the cutting apparatus of one aspect may be
combined with the features of the cutting apparatus of the other
aspect set forth above.
EFFECTS OF THE INVENTION
[0025] According to the present invention, wear on a region other
than the base of the fixing table where an encapsulated body is
fixed can be also prevented.
[0026] The foregoing and other objects, features, aspects and
advantages of the present invention will become more apparent from
the following detailed description of the present invention when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a plan view of an abrasive waterjet type cutting
apparatus according to an embodiment.
[0028] FIG. 2 is a perspective view of a fixing table of a cutting
apparatus according to an embodiment and an encapsulated body
(substrate) that is the object of cutting.
[0029] FIG. 3 is an exploded perspective view of a fixing table
according to an embodiment.
[0030] FIG. 4 is a sectional view of a fixing table when a cutting
apparatus according to an embodiment is carrying out a cutting
operation on a workpiece.
[0031] FIG. 5 is a perspective view of a plurality of package
products produced by the cutting operation of an encapsulated body
(substrate) according to an embodiment.
DESCRIPTION OF THE REFERENCE SIGNS
[0032] 1 encapsulated body; 1a substrate; 1b resin mold; 2 abrasive
waterjet; 3 package product; 4 delivery mechanism; 5 conveyer rail;
6 non-mount face; 7, 7x, 7y cutting line; 8 pump unit; 9 nozzle
system pipe; 10 nozzle; 11 CCD (Charge Coupled Device) camera; 12
transfer mechanism; 50 fixing table; 51 fix position; 52 cut
position; 53 alignment position; 54 mount member; 55 groove; 56
protrusion; 57 base; 58 fix-and-support member; 59 side frame
member; 60 side member; 61 setting table; 62 recess; 63 through
hole; 64 upper surface; 65 protection member; 66 arrow indicating
intake action; 100 cutting apparatus; A carry stage; B prestage; C
cut stage; D rinse-and-dry stage.
BEST MODES FOR CARRYING OUT THE INVENTION
[0033] An abrasive waterjet type cutting apparatus according to an
embodiment of the present invention will be described hereinafter
with reference to FIGS. 1-3. An abrasive waterjet cutting apparatus
100 will be simply referred to as cutting apparatus 100
hereinafter.
[0034] For the sake of simplification, all the drawings employed
for the description set forth below are schematically drawn and may
be partially omitted or depicted in an exaggerated form. In the
embodiment set forth below, an encapsulated body 1 having
semiconductor chips and the like mounted on a circuit board and
sealed together by resin is employed as an example of a workpiece
that is the object of cutting by cutting apparatus 100.
Encapsulated body 1 is cut along two crossing cutting lines
including a curvilinear section.
[0035] In the cutting method employing this cutting apparatus, a
cutting position of high accuracy and a cutting width of
approximately 200 .mu.m are required. Although a cutting apparatus
has been described by the inventors of the present application in
the aforementioned Japanese Patent Application No. 2005-276904 (not
yet published at the time of filing the present application), the
cutting apparatus disclosed therein is definitely only an
embodiment of the cutting apparatus of the present invention, and
the cutting apparatus of the present invention is not limited
thereto.
[0036] Referring to FIG. 1, cutting apparatus 100 according to the
present embodiment includes a carry stage A, a prestage B, a cut
stage C, and a rinse-and-dry stage D. Carry stage A carries an
encapsulated body 1 to cutting apparatus 100. Prestage B receives
encapsulated body 1 from carry stage A to carry encapsulated body 1
to the next stage. Cut stage C receives encapsulated body 1 from
prestage B. On cut stage C, encapsulated body 1 is cut into a
plurality of package products 3 by an abrasive waterjet 2.
Rinse-and-dry stage D receives plurality of package products 3 from
cut stage C for rinsing and drying package products 3.
[0037] Cutting apparatus 100 includes delivery means (not shown)
such as a pusher, grip feed, pickup, and the like to supply
encapsulated body 1 from carry stage A to prestage B. Cutting
apparatus 100 also includes a delivery mechanism 4 such as a
pusher, grip feed, pickup, and the like to carry encapsulated body
1 from prestage B to cut stage C, and to carry plurality of package
products 3 from cut stage C to rinse-and-dry stage D. In the
present embodiment, a mechanical chuck type pickup means is
provided as delivery mechanism 4.
[0038] Each of the delivery means (not shown) and delivery
mechanism 4 can move left and right (X-axis direction), i.e. in the
horizontal direction in FIG. 1, as well as in a direction
perpendicular to the drawing sheet of FIG. 1, i.e. vertical
direction (Z-axis direction).
[0039] In other words the delivery means (not shown) can move
encapsulated body 1 from carry stage A to prestage B. In addition,
delivery mechanism 4 can move encapsulated body 1 from prestage B
to cut stage C, and also move plurality of package products 3 from
cut stage C to rinse-and-dry stage D.
[0040] As shown in FIG. 1, cutting apparatus 100 has carry stage A,
prestage B, cut stage C, and rinse-and-dry stage D arranged
substantially linear so that a process other than predetermined
steps can be completed during the transfer of encapsulated body 1
and package products 3 along one straight line (X-axis direction).
By the arrangement of carry stage A, prestage B, cut stage C, and
rinse-and-dry stage D, the transfer time of encapsulated body 1 and
package products 3 can be shortened.
[0041] The arrangement of the four stages set forth above is not
limited to that set forth above, and any arrangement may be
employed as long as the object of the present invention is
accomplished. The same delivery mechanism 4 may be used to move
encapsulated body 1 during the delivery from carry stage A to
rinse-and-dry stage D. Furthermore, the transfer of encapsulated
body 1 between the stages may be realized by a plurality of
independent delivery mechanisms. In this case, conveyer rail 5 may
differ for each delivery mechanism 4.
[0042] In the usage of cutting apparatus 100, first the delivery
means (not shown) carries encapsulated body 1 from carry stage A to
prestage B. Then, encapsulated body 1 is moved from prestage B to
cut stage C by delivery mechanism 4 along conveyer rail 5. Then, at
cut stage C, encapsulated body 1 is cut to be divided into a
plurality of package products 3.
[0043] Cutting apparatus 100 further includes a product inspection
stage and storage stage not shown. The product inspection stage is
directed to inspecting a plurality of package products 3 subsequent
to completion of the rinsing and drying step carried out at
rinse-and-dry stage D. The storage stage includes a final product
tray (not shown) for receiving and storing a plurality of package
products 3 transferred from the product inspection stage.
[0044] In the present embodiment, encapsulated body 1 includes, as
shown in FIGS. 2 and 4, a substrate 1a, a plurality of electronic
components mounted on one main surface of substrate 1a, and a resin
mold 1b encapsulating the plurality of electronic components all
together in resin.
[0045] In FIG. 5, cutting lines 7 are marked in the X direction and
Y direction at the other surface of encapsulated body 1, i.e. the
non-mount face 6 where electronic components 6 are not placed,
corresponding to the location and number of the plurality of
electronic components. Encapsulated body 1 is cut along each of the
two cutting lines (7x and 7y) to be divided into a plurality of
package products 3.
[0046] In FIG. 5, cutting line 7x in the X direction includes a
curve and straight line whereas a cutting line 7y in the Y
direction includes only a straight line. Cutting line 7 at the
corner where cutting line 7x in the X direction and cutting line 7y
in the Y direction intersect corresponds to a curve. In other
words, cutting lines 7 (7x and 7y) employed in the present
embodiment differ from conventional cutting lines constituted of
only a group of straight lines extending along two orthogonal
directions.
[0047] Encapsulated body 1 is the object of cutting, and includes a
substrate 1a such as a lead frame, printed circuit board or the
like, and a resin mold 1b. Each of the plurality of regions
partitioned by a plurality of cutting lines 7x and a plurality of
cutting lines 7y corresponds to one package product 3 of an
electronic component that is the completed product.
[0048] In the cutting operation of encapsulated body 1, cutting is
first carried out along the shorter side direction (X direction) of
substrate 1a shown in FIG. 5. Then, encapsulated body 1 is cut
along cutting line 7 in succession to the short side direction in
one continuous stroke.
[0049] For example, three package products 3 adjacent to the
aforementioned one short side are cut. Then, the next three package
products 3 adjacent to the aforementioned three package products 3
are cut in one continuous stroke, likewise the previous three
package products 3. Eventually, one encapsulated body 1 is divided
into 18 package products 3.
[0050] Cut stage C includes a reciprocating fixing table 50, as
shown in FIG. 1. Fixing table 50 includes a fix position 51 where
encapsulated body 1 is secured, and a cut position 52 where
encapsulated body 1 is cut. Cut stage C also includes a
reciprocating transfer means (not shown) that moves back and forth
between fix position 51 and cut position 52. The reciprocating
transfer means moves encapsulated body 1 from fix position 51 to
cut position 52.
[0051] An alignment position 53 is provided between fix position 51
and cut position 52. Alignment position 53 is directed to
registration of cutting lines 7 (7x and 7y) marked on non-mount
face 6 of encapsulated body 1.
[0052] Fixing table 50 can reciprocate between fix position 51 and
cut position 52 with encapsulated body 1 or package product 3
secured.
[0053] Furthermore, cutting apparatus 100 includes a transfer
mechanism 12, as shown in FIG. 1. Transfer mechanism 12 moves image
pickup means such as a CCD (Charge Coupled Device) camera 11 for
alignment of nozzle 10 and encapsulated body 1 back and forth
between cut position 52 and alignment position 53 in a two
dimensional plane (X-axis direction and Y-axis direction).
[0054] According to the detailed structure of fixing table 50,
which will be described afterwards, encapsulated body 1 that is the
cutting target is held by suction and the like against fixing table
50.
[0055] In the cutting apparatus of the present embodiment, abrasive
waterjet 2 is sprayed out at high pressure from nozzle 10, whereby
encapsulated body 1 is cut.
[0056] In the cutting method of encapsulated body 1 employing
cutting apparatus 100 of the present embodiment, cut stage C moves
encapsulated body 1 on prestage 5 to fix position 51 using delivery
means, and attaches encapsulated body 1 to fixing table 50 located
at fix position 51.
[0057] Then, fixing table 50 is moved by the reciprocating transfer
means. In association, encapsulated body 1 is moved together with
fixing table 50 to alignment position 53. Substantially at the same
time, cutting apparatus 100 moves CCD camera 11 located above
alignment position 53 in the horizontal direction by means of
transfer mechanism 12. Then, cutting apparatus 100 executes
alignment of encapsulated body 1 taking advantage of the image data
obtained from CCD camera 11.
[0058] Then, encapsulated body 1 is moved from alignment position
53 to cut position 52 by the reciprocating transfer means.
Substantially at the same time, cutting apparatus 100 moves nozzle
10 located above cut position 52 in the horizontal direction by
means of transfer mechanism 12. Accordingly, encapsulated body 1 is
cut along cutting lines 7 (7x and 7y) marked on non-mount face 6 to
be divided into a plurality of package products 3.
[0059] Each of the plurality of package products 3 is moved from
cut position 52 to fix position 51 by the reciprocating transfer
means in the state attached to fixing table 50. The regions of
encapsulated body 1 other than plurality of package products 3 are
dropped towards a dust box (not shown) located beneath cut position
52. In other words, the unwanted regions of encapsulated body 1 are
removed away from fixing table 50. A removal mechanism (not shown)
to remove the unwanted regions from encapsulated body 1 is provided
at nozzle 10. The unwanted regions of encapsulated body 1 may be
removed by the removal mechanism that is moved by delivery
mechanism 12.
[0060] Next, the plurality of package products 3 are transferred to
fix position 51 to be secured at fixing plate 50, and then moved
from cut stage C to rinse-and-dry stage D along conveyer rail 5 by
delivery mechanism 4.
[0061] The operation of each constituent element of cutting
apparatus 100 set forth above is under control of a control unit
(not shown) provided in cutting apparatus 100. This control unit
provides control of carry stage A, prestage B, cut stage C and
rinse-and-dry stage D, as well as abrasive waterjet 2 sprayed out
from nozzle 10 to effect control of cutting encapsulated body 1
along respective cutting lines 7 (7x and 7y) in two crossing
directions including a curvilinear section.
[0062] Cut stage C includes the constituent elements set forth
below as the components of a system for spraying out water
containing abrasive grains at high pressure. These constituent
elements include a high-pressure pump to pressurize water supplied
from an air water source, a switch valve connected to the
high-pressure pump, a first tank connected to the switch valve via
a first flow-in side water system pipe, a second tank connected to
the switch valve via a second flow-in side water system pipe, and a
first flow-out side water system pipe and a second flow-out side
water system connected to the first tank and second tank,
respectively. These constituent elements are depicted as pump unit
8 in FIG. 8.
[0063] As shown in FIG. 1, nozzle system pipe 9 is connected to the
region where the first flow-out side water system pipe and second
flow-out side water system pipe are connected. A cutting nozzle 10
is connected to nozzle system pipe 9. The first and second tanks
are both substantially filled with water containing abrasive
grains.
[0064] Although pump unit 8 is shown installed outside of cut stage
C (cutting apparatus 100), pump unit 8 may be installed in cut
stage C (cutting apparatus 100) instead.
[0065] The abrasive grains in pump unit 8 include silicon carbide
(SiC), alumina (Al.sub.2O.sub.3), garnet, or the like, and has a
grain size of approximately 10 .mu.m to 100 .mu.m. The specific
gravity of these abrasive grains is greater than 1. Therefore, in a
normal state, each of the first and second tanks includes a high
ratio region where there are precipitated abrasive grains at a high
ratio, and a low ratio region composed mainly of water.
[0066] In the present embodiment, "ratio" implies "the ratio of
abrasive grains to the water containing abrasive grains.
Furthermore, in the present embodiment, the first tank and second
tank "substantially filled" with water containing abrasive grains
implies the case where the tank is completely filled with the water
containing abrasive grains, and also the case where there is a
slight amount of bubbles or space remaining in the tank. As will be
described afterwards, the first tank and the second tank preferably
have the same volume since the first tank and second tank are used
in a switching manner.
[0067] Cutting apparatus 100 further includes the constituent
elements set forth below as the components of the system supplying
abrasive grains to the first tank and second tank at pump unit 8.
The constituent elements include an abrasive grain system tank
storing water containing abrasive grains at a high ratio
(hereinafter, referred to as "high ratio water"), and a pump for
pumping out the high ratio water from the abrasive grain system
tank by supplying pressurized water to the abrasive grain system
tank.
[0068] Further, the system includes an abrasive grain supply pipe
for supplying the high ratio water pumped out from the abrasive
grain system tank to the first tank and second tank, a first
abrasive grain supply valve provided at a region of the abrasive
grain supply pipe linking to the first tank, and a second abrasive
grain supply valve provided at a region of the abrasive grain
supply pipe linking to the second tank.
[0069] The system further includes a return pipe for returning the
water overflowing from the first and second tanks to the abrasive
grain system tank when the high ratio water is supplied, a first
return valve provided at a region of the return pipe linking to the
first tank, and a second return valve provided at a region of the
return pipe linking to the second tank. The system also has a water
injection valve to supply externally applied water to the abrasive
grain supply pipe.
[0070] In the system of supplying abrasive grains to the first and
second tanks, each of the first and second tanks is substantially
filled with water containing abrasive grains constantly.
[0071] Cutting apparatus 100 includes the constituent elements set
forth below as the system of maintaining appropriately the ratio of
the abrasive grains in the first tank and the second tank. The
system includes first and second sensors each formed of a load cell
secured to the bottom of the first tank and the second tank.
[0072] This system also includes a control unit (controller). The
control unit receives a signal from the first and second sensors to
calculate the weight of water containing abrasive grains in each of
the first and second tanks based on the received signal. The
control unit controls, as necessary, the valves, pump, and the like
provided at cutting apparatus 100. Although the control unit
controls pump unit 8, each of the constituent elements of the
entire cutting apparatus 100 including the control unit is under
control of a control unit (not shown).
[0073] The cutting nozzle 10 includes a holder, a pole secured in
the holder, a support fitted into the tip of the pole in the
holder, a connector fitted integrally within the support, and a
nozzle tip. A flow channel of a predetermined diameter is provided
at the pole. The connector is formed with a funnel shape cavity, in
communication with the flow channel and having a tapered end.
[0074] The nozzle tip is formed with a small-diameter flow channel
having a predetermined diameter in communication with the outside
space. The tip end of the nozzle tip protrudes by a predetermined
amount from the tip end of both the support and holder. The leading
end of the small-diameter flow channel has a squirt hole.
[0075] The holder, pole, support, connector, and nozzle chip are
formed of, for example, stainless steel, ceramics, or the like. A
wear-resistant coat is applied at the inner wall of the
small-diameter flow channel at the nozzle chip. This wear-resistant
coat is formed by the well known method such as plasma CVD
(Chemical Vapor Deposition).
[0076] The region of the member where the small-diameter flow
channel is formed, i.e. the nozzle chip itself, may be formed of a
wear-resistant material such as sintered diamond. In this case, the
degree of abrasion of the inner wall of the small-diameter flow
channel is reduced since the inner wall of the small-diameter flow
channel is formed of an anti-wear material.
[0077] Fixing table 50 will be described with reference to FIGS.
1-3 hereinafter. Fixing table 50 is the characteristic feature of
cutting apparatus 100 of the present embodiment.
[0078] Fixing table 50 of cutting apparatus 100 of the present
embodiment includes, as shown in FIG. 2, a mount member 54 where
encapsulated body 1 and package product 3 are set, a groove 55
located below cutting line 7 (7x and 7y), and a plurality of
protrusions 56 corresponding to a region other than grooves 55 for
retaining encapsulated body 1 and package products 3.
[0079] Fixing table 50 includes a plurality of bases 57. Each of
the plurality of bases 57 is provided so as to link protrusions 56
together, substantially parallel to cutting line 7 (7x) extending
along at least one of the aforementioned two directions (in this
case, the X direction). The plurality of protrusions 56 and
plurality of bases 57 constitute fix-and-support member 58.
Fix-and-support member 58 is set at a setting table 61. A side
frame member 59 is attached to plurality of bases 57 in a
detachable manner.
[0080] Fixing table 50 further includes a side member 60 extending
substantially parallel to the longer side of rectangular
fix-and-support member 58, at either side of fixing table 50, and
attached to fix-and-support member 58 in a detachable manner.
Fixing table 50 includes setting table 61. Setting table 61 has
mount member 54, fix-and-support member 58, side frame member 59,
and side member 60 attached in a detachable manner. Furthermore,
setting table 61 has an opening located between fix-and-support
member 58 and side member 60.
[0081] FIG. 2 represents an exploded state of fixing table 50. In
the assembling procedure of fixing table 50, fix-and-support member
58, side frame member 59, and side member 60 are attached to
setting table 61, and then mount member 54 is set on
fix-and-support member 58.
[0082] Cutting apparatus 100 of the present embodiment may further
include a container 90 in which fixing table 50 is installed in the
interior cavity, and into which liquid 91 is poured into the
interior cavity. In this case, fixing table 50 is preferably
immersed in liquid 91 so as to avoid direct collision with abrasive
waterjet 2 in container 90. Accordingly, abrasive waterjet 2 has
its energy absorbed by entry into the liquid, and then brought into
contact with the plurality of protrusions 56 and bases 57 of fixing
table 50 with the speed reduced. Therefore, the degree of abrasion
of protrusions 56 and bases 57 is reduced.
[0083] In the case where protrusions 56 and bases 57 are formed of
a material harder than the abrasive grains, container 90 and liquid
91 are not mandatory elements to prevent wear on the plurality of
protrusions and bases. Furthermore, as long as fixing table 50 is
immersed in liquid 91 in container 90, formation of the plurality
of protrusions 56 and bases 57 from a material harder than abrasive
grains is not a mandatory issue to prevent wear on the plurality of
protrusions 56 and bases 57. However, abrasion of protrusions 56
and bases 57 can be prevented more reliably by the combination of
the provision of container 90 and liquid 91 with the formation of
protrusions 56 and bases 57 by a material harder than the abrasive
grains.
[0084] The plurality of protrusions 56 corresponds to the plurality
of package products 3. Recess 62 is provided at mount member 54 so
as to correspond to each of the plurality of protrusions 56. At the
center of each of plurality of recesses 62, a through hole 63
communicating with through hole 63 that extends along the
longitudinal direction of protrusion 56 is formed. Each of the
plurality of through holes 63 is connected to a suction mechanism
(not shown) through a pipe. By the drive of the suction mechanism,
a suction force shown by arrow 66 is generated at the plurality of
through hole 63, whereby encapsulated body 1 or each of the
plurality of package products 3 is adhered to recess 62 by
suction.
[0085] At groove 55 extending along one direction among the
plurality of grooves 55, for example, at groove 55 extending in the
Y direction, a protection member 65 formed of an elongated plate
member is provided so as to cover an upper surface 64 of base
57.
[0086] Each of the plurality of protection members 65 can be
inserted and taken out from groove 55. In addition or
alternatively, the region of fix-and-support member 58 where
abrasive waterjet 2 may contact is formed of a material higher in
hardness than the abrasive grains employed for cutting encapsulated
body 1. Such a material includes, for example, single crystal
diamond, single crystal sapphire, sintered diamond, sintered cubic
boron nitride (cBN), or a composite material in which diamond or
cBN is dispersed in cemented carbide, or a superhard material.
[0087] In the present embodiment, only a portion of fix-and-support
member 58, i.e. only a portion of protrusions 56 and bases 57, is
formed of a material higher in hardness than the abrasive grains in
order to prevent wear caused by contact with abrasive waterjet 2.
However, side frame member 59, side member 60, setting table 61 and
container 90 (the outer wall member) may also be formed of a
material higher in hardness than the abrasive grains. In the case
where fix-and-support member 58 is entirely formed of a material
higher in hardness than the abrasive grains, protection member 65
may not be provided in groove 55.
[0088] Mount member 54 is disposed between encapsulated body 1 and
fix-and-support member 58. The region of mount member 54 where
encapsulated body 1 or plurality of package products 3 are placed
is formed of a material lower in hardness than the abrasive grains
in order to secure encapsulated body 1 and package products 3
reliably by suction. An elastic member such as rubber may be
employed for the material of mount member 54. Mount member 54
includes a plurality of through holes 63 in communication with the
plurality of through holes 63 of the plurality of protrusions 56.
Each of the plurality of through holes 63 of mount member 54 takes
a one-to-one correspondence with the plurality of through holes of
protrusions 56.
[0089] As shown in FIG. 4, mount member 54 is cut at the region
corresponding to cutting line 7 substantially at the same time as
encapsulated body 1 placed on mount member 54 is cut. When
encapsulated body 1 is to be further cut, encapsulated body 1 is
cut in a one-stroke manner, as shown in FIG. 5, along cutting line
7.
[0090] In the present embodiment, a predetermined portion of mount
member 54 is cut. The hardness of this mount member 54 is lower
than that of the abrasive grains. Therefore, occurrence of a
problem such as encapsulated body 1 or package products 3 falling
off or blasted away from fixing table 50, or damage due to
collision between package products 3, can be prevented.
[0091] According to fixing table 50 of the present embodiment,
fix-and-support member 58 is formed of a material higher in
hardness than the abrasive grains. Therefore, the wear on fixing
table 50 where encapsulated body 1 is fixed can be prevented.
Furthermore, mount member 54 is formed of a material lower in
hardness than the abrasive grains. Therefore, mount member 54 can
be secured reliably to fixing table 50 even in the case where
encapsulated body 1 including a cutting line 7 corresponding to a
curvilinear section as well as a straight section is to be cut.
[0092] The function of mount member 54, fix-and-support member 58,
and protection member 65 will be described hereinafter with
reference to FIG. 4.
[0093] Encapsulated body 1 is drawn towards mount member 54 by the
suction action generated in the direction indicated by arrow 66 via
the plurality of through holes 63 and recesses 62. Accordingly,
encapsulated body 1 is secured to fixing table 50, more
specifically, to mount member 54. At this stage, resin mold 1b is
in contact with mount member 54.
[0094] When encapsulated body 1 is cut along the Y-axis direction
according to the cutting method employing cutting apparatus 100 of
the present embodiment, abrasive waterjet 2 is sprayed out at high
pressure from nozzle 10 towards groove 55 to collide against the
upper surface of protection member 65, but not against upper
surface 64 of base 57, as shown in FIG. 4. Accordingly, wear on
fixing table 50, specifically on base 57 of fix-and-support member
58, is prevented.
[0095] When encapsulated body 1 is cut along the X-axis direction,
the same fixing table 50 as that set forth above is used. At this
stage, the moving direction of nozzle 10 is altered to the
direction along cutting line 7x including a curvilinear
section.
[0096] The flow of abrasive waterjet 2 following cutting of
encapsulated body 1 will be described hereinafter. In the case
where encapsulated body 1 is cut along the X-axis direction,
abrasive waterjet 2 flows from groove 55 to the opening extending
along the X-axis direction of setting table 61 and then to a
downstream site of the opening. Therefore, collision of abrasive
waterjet 2 with fixing table 50 is absolutely eliminated.
[0097] When encapsulated body 1 is cut along the Y direction,
abrasive waterjet 2 collides against protection member 65. In other
words, abrasive waterjet 2 does not collide against upper surface
64 of base 57.
[0098] Therefore, even in the case where the same fixing table 50
is used, encapsulated body 1 is cut without damage of fixing table
50. By virtue of the cutting method employing the cutting apparatus
of the present embodiment, wear on at least fix-and-support member
58 of fixing table 50 is prevented.
[0099] In the case where a plurality of encapsulated bodies 1 are
cut in succession, fix-and-support member 58 and protection member
65 will be gradually worn away. In this case, fix-and-support
member 58 and protection member 65 are to be exchanged at an
appropriate time. Thus, encapsulated body 1 can be cut while
preventing wear on fixing table 50.
[0100] Although the present invention has been described and
illustrated in detail, it is clearly understood that the same is by
way of illustration and example only and is not to be taken by way
of limitation, the scope of the present invention being interpreted
by the terms of the appended claims.
* * * * *