U.S. patent application number 14/355730 was filed with the patent office on 2014-09-25 for sheet material processing apparatus, press die, and die setting body.
The applicant listed for this patent is AMADA COMPANY, LIMITED. Invention is credited to Yingjun Jin, Junichi Koyama, Takahiro Shibata.
Application Number | 20140283576 14/355730 |
Document ID | / |
Family ID | 48192119 |
Filed Date | 2014-09-25 |
United States Patent
Application |
20140283576 |
Kind Code |
A1 |
Jin; Yingjun ; et
al. |
September 25, 2014 |
SHEET MATERIAL PROCESSING APPARATUS, PRESS DIE, AND DIE SETTING
BODY
Abstract
A sheet material processing apparatus has a pressurizing part of
a sheet material and a supporting part of the pressurized sheet
material. The apparatus includes an end face pressing upper press
die that receives a pressurizing force, an end face pressing lower
press die that is arranged on the supporting part and faces the end
face pressing upper press die so that an end face of the sheet
material is inserted between the end face pressing upper and lower
press dies, an end face pressing part that, with the end face
pressing upper press die being moved toward the end face pressing
lower press die, presses the end face of the sheet material, and an
end face pressing width adjusting part that sets a pressing width
of the end face of the sheet material.
Inventors: |
Jin; Yingjun; (Kanagawa,
JP) ; Shibata; Takahiro; (Kanagawa, JP) ;
Koyama; Junichi; (Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AMADA COMPANY, LIMITED |
Kanagawa |
|
JP |
|
|
Family ID: |
48192119 |
Appl. No.: |
14/355730 |
Filed: |
November 1, 2012 |
PCT Filed: |
November 1, 2012 |
PCT NO: |
PCT/JP2012/078319 |
371 Date: |
May 1, 2014 |
Current U.S.
Class: |
72/404 ; 72/412;
72/413 |
Current CPC
Class: |
B21D 19/08 20130101;
B21D 5/0209 20130101; B21D 5/02 20130101 |
Class at
Publication: |
72/404 ; 72/412;
72/413 |
International
Class: |
B21D 5/02 20060101
B21D005/02; B21D 19/08 20060101 B21D019/08 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 4, 2011 |
JP |
2011-242501 |
Oct 12, 2012 |
JP |
2012-226724 |
Claims
1. A sheet material processing apparatus having a pressurizing part
for pressurizing a sheet material and a supporting part for
supporting the pressurized sheet material, characterized in that
the apparatus comprises: an end face pressing upper press die that
receives a pressurizing force from the pressurizing part; an end
face pressing lower press die that is arranged on the supporting
part and faces the end face pressing upper press die so that an end
face of the sheet material is inserted between the end face
pressing upper and lower press dies; an end face pressing part
that, with the pressurizing force from the pressurizing part moving
the end face pressing upper press die toward the end face pressing
lower press die, presses one end face of the sheet material along a
bend line of the sheet material to be bent; and an end face
pressing width adjusting part that sets a pressing width of the one
end face of the sheet material so that, when the end face pressing
part presses the one end face, a contact face of the one end face
of the sheet material comes in front of, in a direction in which
the sheet material is inserted between the end face pressing upper
and lower press dies, a pressurizing center of the pressurizing
force applied from the pressurizing part to the end face pressing
upper press die.
2. The sheet material processing apparatus according to claim 1,
characterized in that: the end face pressing lower press die is
divided into a plurality of press dies that are able to press the
end face of the sheet material against the end face pressing upper
press die; and the divided press dies are configured to be
selectively used when pressing the end face of the sheet
material.
3. The sheet material processing apparatus according to claim 2,
characterized in that each of the press dies is configured to be
moved in a direction intersecting with a direction in which the end
face pressing upper press die is driven toward the end face
pressing lower press die, to realize the selective use.
4. The sheet material processing apparatus according to claim 3,
characterized in that the end face pressing width adjusting part
includes at least one of the press dies that is moved and
positioned by a back gauge of the processing apparatus in the
intersecting direction and a stopper that is arranged on the one
press die and the sheet material is brought into contact with.
5. The sheet material processing apparatus according to claim 1,
characterized in that the apparatus comprises a hemming part to hem
the sheet material.
6. The sheet material processing apparatus according to claim 5,
characterized in that the hemming part is configured with the end
face pressing part.
7. The sheet material processing apparatus according to claim 1,
characterized in that the apparatus comprises: a driver generating
the pressurizing force of the pressurizing part; and a bending part
integrally supported with the end face pressing part and having a
punch-side member that presses the sheet material with a punch
under the pressurizing force of the pressurizing part and a
die-side member having a die on the supporting part that supports
the sheet material pressed with the punch, the bending part bending
the sheet material between the punch and the die.
8. The sheet material processing apparatus according to claim 7,
characterized in that the plurality of divided press dies of the
end face pressing lower press die include fixed dies having a fixed
height position and movable dies arranged adjacent to the fixed
dies and having height positions to be changed with respect to the
height position of the fixed dies, the movable dies being provided
with a height adjusting mechanism to change the height positions of
the movable dies.
9. The sheet material processing apparatus according to claim 7,
characterized in that the apparatus comprises a pressing width
adjusting mechanism adjusting a pressing width of the sheet
material from the one end face of the sheet material, the pressing
width adjusting mechanism including an end face stopper bar that is
arranged to appear and disappear from the end face pressing lower
press die and is inserted between the die-side member and the end
face pressing lower press die so that the one end face of the sheet
material set on the end face pressing lower press die comes into
contact with the stopper bar and a mover that moves the end face
pressing lower press die together with the stopper bar in a
direction intersecting with the direction in which the punch
presses the die.
10. The sheet material processing apparatus according to claim 7,
characterized in that the die-side member is moved by a bending
force of the driver toward the end face pressing lower press die to
press the one end face of the sheet material against the end face
pressing lower press die.
11. The sheet material processing apparatus according to claim 7,
characterized in that the die-side member includes a lower table
and a die holder to support the die on the lower table, the lower
table has the end face pressing upper press die, and the lower
table is movable toward the end face pressing lower press die when
the driver presses the punch toward the die, thereby pressing the
one end face of the sheet material against the end face pressing
lower press die.
12. The sheet material processing apparatus according to claim 8,
characterized in that the height adjusting mechanism moves the
movable dies toward or away from the die-side member, thereby
adjusting the height positions of the movable dies.
13. The sheet material processing apparatus according to claim 7,
characterized in that the apparatus comprises a hemming part to hem
the sheet material.
14. The sheet material processing apparatus according to claim 13,
characterized in that the hemming part is configured with the end
face pressing part.
15. A press die installed on and used by a processing apparatus
that employs a punch, a die, and a pressurizing part to bend a
sheet material, characterized in that the press die comprises: an
end face pressing upper press die that receives a pressurizing
force from the pressurizing part that drives the punch toward the
die; an end face pressing lower press die that is arranged to face
the end face pressing upper press die so that an end face of the
sheet material is inserted between the end face pressing upper and
lower press dies; an end face pressing part that, with the
pressurizing force from the pressurizing part moving the end face
pressing upper press die toward the end face pressing lower press
die, presses one end face of the sheet material along a bend line
of the sheet material to be bent; and an end face pressing width
adjusting part that sets a pressing width of the one end face of
the sheet material so that, when the end face pressing part presses
the one end face, a contact face of the one end face of the sheet
material comes in front of, in a direction in which the sheet
material is inserted between the end face pressing upper and lower
press dies, a pressurizing center of the pressurizing force applied
from the pressurizing part to the end face pressing upper press
die.
16. The press die according to claim 15, characterized in that the
end face pressing lower press die is divided into a plurality of
press dies in a direction of the bend line of the sheet material to
be bent, the divided press dies being configured to be selectively
used when pressing the end face extending along the bend line of
the sheet material.
17. The press die according to claim 16, characterized in that each
of the press dies is configured to be moved in a direction
intersecting with a direction in which the pressurizing part drives
the punch toward the die, to realize the selective use.
18. The press die according to claim 17, characterized in that:
some of the press dies are configured to be moved and positioned by
a back gauge of the processing apparatus in the intersecting
direction; and the press dies to be moved and positioned by the
back gauge in the intersecting direction are each provided with a
stopper which the sheet material is brought into contact with.
19. The press die according to claim 15, characterized in that the
press die comprises a hemming part to hem the sheet material.
20. The press die according to claim 19, characterized in that the
hemming part is configured with the end face pressing part.
21. A die setting body installed on and used by a processing
apparatus that employs a punch and a die to bend a sheet material,
characterized in that the die setting body comprises: a die setting
part on which the die is set; and an end face pressing part that
presses an end face area of the sheet material along a bend line
along which the sheet material is bent by the punch and the die set
on the die setting part, the end face pressing part being
positioned opposite to an apparatus base of the processing
apparatus with a pressurizing center of the punch and die being
interposed between the end face pressing part and the apparatus
base.
22. The die setting body according to claim 21, characterized in
that the end face pressing part is divided into a plurality of
press dies in a direction of the bend line of the sheet material to
be bent, the divided press dies being configured to be selectively
used when pressing the end face area extending along the bend line
of the sheet material.
23. The die setting body according to claim 22, characterized in
that the selective use of the divided press dies is realized by
configuring each of the press dies to be moved in a direction
intersecting with a direction in which the punch is driven toward
the die set on the die setting body to bend the sheet material
between the punch and the die.
24. The die setting body according to claim 23, characterized in
that: some of the press dies are configured to be moved and
positioned by a back gauge of the processing apparatus in the
intersecting direction; and the press dies to be moved and
positioned by the back gauge in the intersecting direction are each
provided with a stopper which the sheet material is brought into
contact with.
25. The die setting body according to claim 21, characterized in
that the die setting body comprises a hemming part to hem the sheet
material.
26. The die setting body according to claim 25, characterized in
that the hemming part is configured with the end face pressing
part.
Description
TECHNICAL FIELD
[0001] The present invention relates to a processing apparatus for
processing a metallic sheet material, a press die, and a die
setting body, and particularly, to a sheet material processing
apparatus having a function of bending a sheet material and/or a
function of pressing an end of the sheet material.
BACKGROUND ART
[0002] Laser-cutting or shearing a metallic sheet material, and
thereafter, bending the sheet material frequently cause a warp S
such as a boat warp on the sheet material W as illustrated in FIG.
12. It is known that the warp S occurs when the sheet metal W to be
bent has a relatively small width and a relatively long ridge to be
bent.
[0003] To suppress such a warp on a sheet material, the sheet
material, which has been cut, is passed through a leveler and bent,
or is first bent by press machine, reversed, and pressed to correct
a warp. Using a leveler has a problem that a leveler capable of
dealing with sheet materials of various sizes must be prepared
between a cutting process and a bending process. Bending a sheet
material by press machine and then correcting a warp have a problem
that the warp correction is difficult.
[0004] Japanese Unexamined Patent Application Publication No.
2005-177790 (Patent Literature 1), for example, provides a die with
a shape to give a sheet material a warp in a direction opposite to
a U-bend to be applied to the sheet material and carries out a
bending process in two steps by using retortion, thereby reducing a
warp. Japanese Unexamined Patent Application Publication No.
2006-15404 (Patent Literature 2) bends a Z-shaped material or a hat
channel material with a die, conducts retortion, and through these
two steps, reduces a warp.
[0005] The Patent Literature 1, however, needs a special die, is
unable to flexibly handle various sizes of sheet materials, and
complicates the shape of a processed sheet material.
[0006] The Patent Literature 2 carries out a bending process in two
steps to elongate a processing time and is unable to deal with
special shapes.
[0007] The inventors of the present invention have studied a
mechanism of a longitudinal warp in a bending process such as a
V-bending process, clarified the occurrence and suppression of a
warp in the bending process, and filed Japanese Patent Application
No. 2011-5649 and Japanese Patent Application No. 2011-242372 that
is a domestic priority claim application based on the Japanese
Patent Application No. 2011-5649. These applications pressurize a
cut edge of a sheet material to increase or decrease residual
stress caused in the sheet material at the time of cutting the
sheet material, thereby suppressing a warp.
SUMMARY OF INVENTION
Problems to be Solved by Invention
[0008] Bending a sheet material according to the proposals of the
inventors of the present invention needs, in addition to a bending
machine for bending the sheet material, a press machine for
pressing a cut edge of the sheet material and necessitates pressing
an end face of the sheet material by the press machine, and
thereafter, moving the sheet material to the bending machine. This
makes the handling of the sheet material troublesome and time and
labor consuming.
[0009] To cope with this, pressing an end face of a sheet material
and bending the same may be conducted by a single bending machine.
This, however, requires a die for pressing the end face of the
sheet material and a die for bending the sheet material must be
replaced with each other according to a process to be carried out
on the sheet material. This causes problems of increasing work
steps and making the handling of the sheet material
troublesome.
[0010] Using a bending machine to press an end face of a sheet
material in a thickness direction for a predetermined width (for
reducing a warp to be caused in a bending process) raises a problem
that, depending on a pressing mode, the part of the sheet material
to be pressed is incorrectly pressed.
Means to Solve Problems
[0011] The present invention is able to provide a sheet metal
processing apparatus, a press die, and a die setting body (for
supporting a die set on the processing machine), capable of easily
handling a sheet material and improving workability.
[0012] Also, the present invention is able to provide a processing
apparatus, a press die, and a die setting body, capable of
correctly pressing a sheet material so as to minimize a warp that
may occur when bending the sheet material.
[0013] A first technical aspect of the present invention provides a
sheet material processing apparatus having a pressurizing part to
pressurize a sheet material and a supporting part to support the
sheet material pressurized by the pressurizing part. The processing
apparatus includes an end face pressing upper press die that
receives a pressurizing force from the pressurizing part, an end
face pressing lower press die that is arranged on the supporting
part and faces the end face pressing upper press die so that an end
face of the sheet material is inserted between the end face
pressing upper and lower press dies, an end face pressing part
that, with the pressurizing force from the pressurizing part moving
the end face pressing upper press die toward the end face pressing
lower press die, presses the end face of the sheet material along a
bend line of the sheet material to be bent, and an end face
pressing width adjusting part that sets a pressing width of the end
face of the sheet material so that, when the end face pressing part
presses the end face, a contact face of the end face of the sheet
material comes in front of, in a direction in which the sheet
material is inserted between the end face pressing upper and lower
press dies, a pressurizing center of the pressurizing force applied
from the pressurizing part to the end face pressing upper press
die.
[0014] A second technical aspect of the present invention provides
a press die installed on and used by a processing apparatus that
employs a punch, a die, and a pressurizing part to bend a sheet
material. The press die includes an end face pressing upper press
die that receives a pressurizing force from the pressurizing part
that drives the punch toward the die, an end face pressing lower
press die that is arranged to face the end face pressing upper
press die so that an end face of the sheet material is inserted
between the end face pressing upper and lower press dies, an end
face pressing part that, with the pressurizing force from the
pressurizing part moving the end face pressing upper press die
toward the end face pressing lower press die, presses the end face
of the sheet material along a bend line of the sheet material to be
bent, and an end face pressing width adjusting part that sets a
pressing width of the end face of the sheet material so that, when
the end face pressing part presses the end face, a contact face of
the end face of the sheet material comes in front of, in a
direction in which the sheet material is inserted between the end
face pressing upper and lower press dies, a pressurizing center of
the pressurizing force applied from the pressurizing part to the
end face pressing upper press die.
[0015] A third technical aspect of the present invention provides a
die setting body installed on and used by a processing apparatus
that employs a punch and a die to bend a sheet material. The die
setting body includes a die setting part on which the die is set
and an end face pressing part that presses an end face area of the
sheet material along a bend line along which the sheet material is
to be bent by the punch and the die set on the die setting part.
The end face pressing part is positioned opposite to an apparatus
base of the processing apparatus with a pressurizing center of the
punch and die being interposed between the end face pressing part
and the apparatus base.
BRIEF DESCRIPTION OF DRAWINGS
[0016] FIG. 1 is a side view generally illustrating a bending
apparatus according to a first embodiment of the present
invention.
[0017] FIG. 2 is a perspective view illustrating a bending part of
the bending apparatus.
[0018] FIG. 3 is a perspective view illustrating a backside of the
bending part of the bending apparatus.
[0019] FIG. 4 is a perspective view illustrating a height adjusting
mechanism of an end face pressing part.
[0020] FIG. 5 is a side view illustrating the height adjusting
mechanism.
[0021] FIG. 6 is a perspective view illustrating the height
adjusting mechanism with an end face pressing lower press die being
omitted.
[0022] FIG. 7 is a front view illustrating an action of the height
adjusting mechanism.
[0023] FIG. 8 is a side view illustrating a pressing width
adjusting mechanism.
[0024] FIG. 9 is a plan view illustrating the pressing width
adjusting mechanism.
[0025] FIG. 10 is a perspective view illustrating the pressing
width adjusting mechanism.
[0026] FIG. 11 is a perspective view illustrating the pressing
width adjusting mechanism.
[0027] FIG. 12 is a perspective view illustrating a sheet material
causing a warp after a bending process.
[0028] FIG. 13 is a front view generally illustrating a bending
apparatus according to a second embodiment of the present
invention.
[0029] FIG. 14 is a side view seen from an arrow XIV of FIG. 13,
generally illustrating the bending apparatus and corresponding to
FIG. 2.
[0030] FIG. 15 is a perspective view illustrating a die setting
body installed on the bending apparatus with a cover plate being
removed.
[0031] FIG. 16 is a sectional view along XVI-XVI of FIG. 15.
[0032] FIG. 17 is a simplified view of FIG. 16.
[0033] FIG. 18 is a simplified sectional view along XVIII-XVIII of
FIG. 15.
[0034] FIG. 19 is a view illustrating a state that a die holder
(upper press die) is lowered from the state of FIG. 17 and a lower
press die and the upper press die hold and press an end face of a
sheet material.
[0035] FIG. 20 is a view illustrating a state that the lower press
die is moved backward from the state of FIG. 17, the die holder
(upper press die) is lowered, and the end face of the sheet
material is not held or pressed.
[0036] FIG. 21 is a view illustrating a state that a stopper
(stopper support) is moved to a rear end from the state of FIG.
18.
[0037] FIG. 22 is a view illustrating a state that a sheet material
to be hemmed is set on the lower press die in the state of FIG.
21.
[0038] FIG. 23 is a view illustrating a state that the die holder
(upper press die) is lowered from the state of FIG. 22 and the
lower and upper press dies hold, press, and hem an end face of the
sheet material.
[0039] FIG. 24 is a view illustrating a state that a die (the die
holder) is lowered from the state of FIG. 17, a sheet material is
set on the die, and a punch is lowered to hold and bend the sheet
material against the die.
[0040] FIG. 25 is an enlarged view illustrating a part XXV of FIG.
24.
[0041] FIG. 26 is a perspective view illustrating a part for
pressing a sheet material of a bending apparatus according to a
third embodiment of the present invention with an end face pressing
upper press die being lifted.
[0042] FIG. 27 is a view illustrating a state that the end face
pressing upper press die is lowered from the state of FIG. 26, to
press an end face of a sheet material (to reduce a warp to be
caused when bending the sheet material).
[0043] FIG. 28 is a view illustrating a state that the end face
pressing upper press die is lowered from the state of FIG. 26, to
hem the sheet material.
[0044] FIG. 29 is a view seen from an arrow XXIX of FIG. 26.
[0045] FIG. 30 is a side view illustrating behaviors of the end
face pressing upper and lower press dies during the pressing
process of FIG. 27.
MODE OF IMPLEMENTING INVENTION
First Embodiment
[0046] The present invention will be explained in detail according
to the illustrated embodiments. FIG. 1 to 12 illustrate a sheet
material bending apparatus (sheet material processing apparatus) 1
according to the first embodiment of the present invention, in
which FIG. 1 is a side view generally illustrating the apparatus
and FIGS. 2 and 3 are perspective front and backside views
illustrating a bending part 2. FIGS. 4 to 7 illustrate an end face
pressing part 3 and a height adjusting mechanism 41 of the end face
pressing part 3, FIGS. 8 to 11 illustrate a pressing width
adjusting mechanism 51 of the end face pressing part 3, and FIG. 12
illustrates press control of an end face of a sheet material.
[0047] The sheet material bending apparatus (for example, a press
brake) 1 has a function of bending a metallic sheet material (sheet
work) W, and in addition, a function of pressing an end face of the
sheet material W to adjust residual stress caused by cutting the
sheet material W. For this, as illustrated in FIG. 1, the bending
apparatus 1 includes the bending part 2 for bending, for example,
V-bending the sheet material W, the end face pressing part 3 for
pressing one end face of the sheet material W before bending the
sheet material, and an apparatus base 5 for integrally supporting
them.
[0048] The apparatus base 5 includes an upper base 5a and a lower
base 5b that are connected to each other so that they vertically
face each other to form an elongated U-shape (or C-shape) when seen
from a side. The bending part 2 is arranged on the upper base 5a
and the end face pressing part 3 is arranged on the lower base 5b
so that the end face pressing part 3 is under the bending part 2
and faces the same. In the bending apparatus 1, the end face
pressing part 3 presses the one end face of the sheet material W
cut by, for example, laser or shearing, thereby increasing or
decreasing residual stress. After the one end face is pressed, the
sheet material W is bent by the bending part 2. This results in
reducing an occurrence of a warp of the sheet material W to be
bent.
[0049] As illustrated in FIG. 1, the bending part 2 has a
punch-side member 11 arranged on the upper base 5a, a die-side
member 12 arranged under the punch-side member 11, and a bending
driver (driver) 13 made of a hydraulic cylinder to drive the
punch-side member 11. The hydraulic cylinder may be another
actuator such as a servo motor. The bending driver 13, i.e., the
hydraulic cylinder is vertically oriented and is attached to the
upper base 5a of the apparatus base 5, so that extending and
contracting actions thereof vertically move the punch-side member
11 toward and away from the die-side member 12. Instead of or in
addition to vertically moving the punch-side member 11, the
die-side member 12 may be configured to vertically move.
[0050] The punch-side member 11 is arranged under the bending
driver 13 and has a punch 14 for pressing the sheet material W, a
punch holder 15 to which the punch 14 is attached, and an upper
table 16 to which the punch holder 15 is attached. The upper table
16 is connected to the bending driver 13 so that driving the
bending driver 13 results in vertically moving the upper table 16,
punch holder 15, and punch 14 to press the sheet material W.
[0051] The die-side member 12 faces the punch 14 and has a die 17
for receiving the sheet material W pressed by the punch 14, a die
holder (first die holder) 18 for supporting a lower part of the die
17, and a lower table (second die holder) 21. The lower table 21
and die holder 18 sandwich and hold the die 17. Protruding from an
upper part of the lower table 21 is a hold piece 21a that faces the
die holder 18. The die 17 has a leg 17a that is held between the
die holder 18 and the hold piece 21a. In this state, the die holder
18 is tightened with a screw to hold the die 17 between the die
holder 18 and the lower table 21.
[0052] The lower table 21 is attached to a base frame 25 that is
fixed to the lower base 5b of the apparatus base 5, so that the
die-side member 12 as a whole is supported by the base frame 25.
The base frame 25 has an L-shape in a side view and includes an
upright side wall 25a. The lower table 21 is vertically movably
attached to the side wall 25a of the base frame 25. As illustrated
in FIG. 3, the side wall 25a of the base frame 25 has a plurality
of vertically elongated long holes 26 at predetermined intervals. A
back face of the lower table 21 is provided with a plurality of
screws 27 that pass through the long holes 26, respectively. In
this way, the lower table 21 is vertically movably attached to the
base frame 25. With this configuration, the punch 14 is moved
toward the die 17 to press the sheet material W against the die 17.
Pressure of the punch 14 provides a downward moving force onto the
lower table 21, and therefore, the lower table 21 moves in the same
direction. Arranged inside the side wall 25a of the base frame 25
are return springs 28 corresponding to the screws 27. The return
springs 28 are compressed by the downward movement of the lower
table 21 and reaction force thereof returns the lower table 21 to
an original height position.
[0053] The bending part 2 bends the sheet material W into, for
example, a V-shape and the bending of the sheet material W is
conducted along a pressing center 7 (refer to FIG. 1) of the punch
14 and die 17.
[0054] The end face pressing part 3 has an end face pressing lower
press die 31 arranged to face the lower table 21. The end face
pressing lower press die 31 presses the end face of the sheet
material W along a bend line of the sheet material W to be bent.
The end face side of the sheet material W is placed on the end face
pressing lower press die 31. In this state, the punch 14 is moved
toward the die 17 to move the lower table 21 in the same direction.
The movement of the lower table 21 holds the sheet material W
between the lower table 21 and the end face pressing lower press
die 31, thereby pressing the vicinity of the end face 19 of the
sheet material W. To achieve this, a lower end of the lower table
21 corresponding to the end face pressing lower press die 31 is an
end face pressing upper press die 32.
[0055] According to this configuration, the bending part 2 for
bending the sheet material W and the end face pressing part 3 for
pressing the end face of the sheet material W to suppress a warp of
the sheet material W are arranged on the single apparatus base 5.
Accordingly, the single apparatus is able to press the end face of
the sheet material W and bend the sheet material W. This
configuration easily handles the sheet material W, thereby
improving workability. Pressing the end face 19 of the sheet
material W to control residual stress of the sheet material W is
carried out by using the drive force of the bending driver 13 of
the bending part 2. This necessitates no separate driving source
for pressing the end face 19 of the sheet material W, thereby
simplifying the apparatus and saving energy.
[0056] As illustrated in FIG. 2, the end face pressing lower press
die 31 has a plurality of fixed dies 33 and a plurality of movable
dies 35. The fixed dies 33 are fixed in their height positions and
are arranged on the base frame 25. The movable dies 35 are arranged
adjacent to the fixed dies 33 and their height positions are
changeable relative to the fixed dies 33. Changing the height
positions of the movable dies 35 is carried out by a height
adjusting mechanism 41.
[0057] As illustrated in FIGS. 4 to 6, the height adjusting
mechanism 41 has a height adjust drive source 42 arranged behind
the base frame 25 and a shim 43 arranged above the base frame 25.
The height adjust drive source 42 may be a cylinder or a motor.
According to this embodiment, it is a cylinder. The shim 42 is a
flat plate and is arranged above the base frame 25 to face a lower
face of the movable die 35. The lower face of the movable die 35
opposing the shim 43 is a stepped face including a higher plane 35a
and a lower plane 35b.
[0058] The flat shim 43 is movable above the base frame 25 in a
direction toward or away from the die-side member 12. To realize
this movement, the height adjust drive source 42 has a piston 42a
whose front end is provided with a connection bracket 44. To a
front end of the connection bracket 44, the shim 43 is attached.
The connection bracket 44 slides when driven by the height adjust
drive source 42 in the above-mentioned direction toward or away
from the die-side member 12.
[0059] When this movement causes the shim 43 to face the higher
plane 35a, a large gap is created between the shim 43 and the
higher plane 35a of the movable die 35, and therefore, the movable
die 35 can be lowered by the large gap. In the lowered state, the
movable die 35 is irrelevant to the pressing of the sheet material
W. This state is illustrated in FIG. 7 in which the movable dies 35
are lower than the fixed dies 33. If, in this state, the punch 14
is lowered to lower the lower table 21, the end face pressing upper
press die 32 of the lower table 21 and the fixed dies 33 press the
end face of the sheet material W. The movable dies 35, however,
conduct no pressing. When the shim 43 is moved to face the lower
plane 35b to approach the lower plane 35b, a top face of each
movable die 35 agrees with that of the fixed die 33 and stops
thereat. In this lifted state of the movable dies 35, the movable
dies 35 and fixed dies 33 together press the sheet material W.
[0060] By changing the height position of each movable die 35, the
end face pressing lower press die 31 is able to partially press the
end face of the sheet material W. It is possible, therefore, to
press necessary parts of the sheet material W.
[0061] The bending apparatus 1 according to the present embodiment
is able to adjust a pressing width of the end face of the sheet
material W. This adjustment is carried out by the pressing width
adjusting mechanism 51.
[0062] As illustrated in FIGS. 8 to 11, the pressing width
adjusting mechanism 51 has end face stopper bars 53 arranged on the
end face pressing lower press die 31 and a back gauge (not
illustrated) to move the end face pressing lower press die 31.
[0063] The end face stopper bar 53 is arranged on the fixed die 33
of the end face pressing lower press die 31 and is inserted between
the fixed die 33 and the lower table 21 of the die-side member 12.
Inserted between the fixed die 33 and the lower table 21, the end
face stopper bar 53 faces the end face 19 of the sheet material W
set on the end face pressing lower press die 31 (refer to FIG. 1)
and comes into contact with the end face 19 of the sheet material
W. This results in stopping the sheet material W on the end face
pressing lower press die 31. Accordingly, dimensions of a pressed
face at the end face 19 of the sheet material W are adjustable.
[0064] As illustrated in FIG. 11, the present embodiment provides
the fixed die 33 with a bar accommodation groove 56 into which the
end face stopper bar 53 is received. The bar accommodation groove
56 contains a coil-shaped support spring 57 that supports the end
face stopper bar 53. In such a support structure, the lower table
21 descends to come into contact with the end face stopper bar 53
and the end face stopper bar 53 compresses the support coil spring
57 and enters into the bar accommodation groove 56. When the lower
table 21 ascends, the torque of the compressed support spring 57
pushes the end face stopper bar 53 out of the bar accommodation
groove 56 so that the end face stopper bar 53 appears from the top
face of the fixed die 33. In this way, the end face stopper bar 53
is able to appear and disappear from the fixed die 33.
[0065] The back gauge serves as a mover to move the fixed dies 33
in a direction orthogonal to the direction in which the punch 14 is
pressed to the die 17. The back gauge is, for example, a cylinder
to which connection blocks 59 are connected. Each connection block
59 is attached to the fixed die 33. In this configuration, a
pressing operation of the back gauge advances each fixed die 33 in
the direction orthogonal to the direction in which the punch 14
presses the die 17. As illustrated in FIGS. 9 to 11, a back face of
the fixed die 33 is in contact with a return spring 60 that is
compressed when the fixed die 33 advances. When the back gauge
stops, the advanced fixed die 33 returns to an original position
due to reaction of the bent return spring 60.
[0066] The pressing width adjusting mechanism 51 of the
above-mentioned configuration moves the fixed dies 33 in the
direction orthogonal to the pressing direction of the punch 14
toward the die 17, thereby adjusting a contact position of the end
face stopper bars 53 with respect to the end face of the sheet
material W. Accordingly, a pressing dimension (width in an
insertion direction) of the end face 19 of the sheet material W to
be pressed by the lower table 21 (the end face pressing upper press
die 32) and the end face pressing lower press die 31 is adjustable
according to residual stress of the sheet material W.
[0067] Namely, it is possible to easily control the residual stress
of the sheet material W.
[0068] To adjust the pressing width of the end face of the sheet
material W with the pressing width adjusting mechanism 51, the end
face 19 of the sheet material W is inserted between the lower table
21 and the end face pressing lower press die 31 toward the die-side
member 12. Thereafter, the bending driver 13 is driven to move
(lower) the punch 14 toward the die 17 to lower the lower table 21
under the die 17 so that the end face side (an edge area adjacent
to the end face 19) of the sheet material W is pressed between the
end face pressing upper press die 32 of the lower table 21 and the
end face pressing lower press die 31.
[0069] As illustrated in FIG. 1, the part of the sheet material W
to be pressed (the part held between and pressed by the end face
pressing upper press die 32 and the fixed dies 33 and movable dies
35) is positioned on the insertion side of the sheet material W
from the pressing center 7 of the punch 14 and die 17. The pressing
width adjusting mechanism 51 may move the fixed dies 33 to move the
end face stopper bars 53 relative to the pressing center, so that
the pressed width of the sheet material W is properly adjusted. The
pressed part of the sheet material W may be positioned so that part
thereof is beyond the pressing center 7 in the insertion direction
of the sheet material W.
[0070] The embodiment mentioned above is capable of precisely
setting the position of the end face 19 of the sheet material W,
i.e. the position of an area around the end face of the sheet
material W to be pressed, with the use of the pressing width
adjusting mechanism 51. Accordingly, the embodiment is capable of
properly dealing with the problem of residual stress of the sheet
material.
[0071] As explained above, the sheet material bending apparatus 1
according to the present embodiment has the bending part 2 for
bending the sheet material W and the end face pressing part 3 for
pressing an end face of the sheet material W to suppress a warp,
the parts 2 and 3 being arranged on the single apparatus base 5.
Accordingly, the single apparatus can carry out an end-face
pressing process and a bending process on the sheet material W, to
make the handling of the sheet material easier and improve
workability.
[0072] The pressing width adjusting mechanism 51 having the end
face stopper bars 53 to be brought into contact with an end face of
the sheet material W is able to adjust a pressing width of the end
face 19 of the sheet material W. Namely, press dimensions around
the end face of the sheet material W are adjustable according to
residual stress of the sheet material W to easily control the
residual stress of the sheet material W.
[0073] Pressing the end face of the sheet material W by the end
face pressing part 3 to control the residual stress of the sheet
material W is achieved by using the driving force of the bending
driver 13 of the bending part 2 for bending the sheet material W.
This eliminates a need of an additional drive source for pressing
the end face of the sheet material W, simplifies the structure of
the apparatus, and saves energy.
Second Embodiment
[0074] A processing apparatus (sheet material bending apparatus)
101 according to the second embodiment is configured similar to the
bending apparatus 1 according to the first embodiment. It has a
function of bending a metallic sheet material (sheet work) W and a
function of pressing an end face of the sheet material W to adjust
residual stress caused by cutting. It operates like the bending
apparatus 1 of the first embodiment and provides like effects.
[0075] As illustrated in FIGS. 13, 14, 19, 24, and the like, the
bending apparatus (for example, a press brake) 101 has a bending
part 103 for bending, for example, V-bending the sheet material W,
an end face pressing part 105 for pressing one end face of the
sheet material W before bending the sheet material W, and a
C-shaped apparatus base 107 for supporting them together.
[0076] As illustrated in FIG. 14, the apparatus base 107 includes
an upper base 107a and a lower base 107b that are connected to each
other so that they vertically face each other to form a C-shape
when seen from a side. The bending part (bending press part) 103 is
arranged on the upper base 107a and the pressing part (end face
pressing part) 105 is arranged on the lower base 107b so that the
end face pressing part 105 is under the bending part 103 and faces
the same.
[0077] In the bending apparatus 101, the end face pressing part 105
presses an end face of the sheet material W cut by, for example,
laser or shearing, thereby increasing or decreasing residual
stress. After the end face or both end faces are pressed, the sheet
material W is bent by the bending part 103. This results in
suppressing an occurrence of a warp and bending the sheet material
W with a minimized boat warp.
[0078] The bending part 103 has a punch-side member 109 arranged on
the upper base 107a, a die-side member 111 arranged on the lower
base 107b under the punch-side member 109, and a bending driver
(driver) 113 made of a hydraulic cylinder 163 or a servo motor to
drive the punch-side member 109. The hydraulic cylinder 163 of the
bending driver 113 is vertically oriented and is attached to the
upper base 107a of the apparatus base 107, so that extending and
contracting actions thereof vertically move the punch-side member
109 toward and away from the die-side member 111.
[0079] Changing pressure of hydraulic oil supplied to the hydraulic
cylinder 163 results in adjusting thrust of the punch-side member
109. Instead of or in addition to vertically moving the punch-side
member 109, the die-side member 111 may be configured to vertically
move.
[0080] The punch-side member 109 is arranged under the bending
driver 113 and has a punch 115 for pressing the sheet material W, a
punch holder 117 to which the punch 115 is integrally attached, and
an upper table 119 to which the punch holder 117 is integrally
attached. The upper table 119 is connected to the bending driver
113 so that driving the bending driver 113 results in vertically
moving the upper table 119, punch holder 117, and punch 115 to
press the sheet material W.
[0081] The die-side member 111 faces the punch 115, and as
illustrated in FIGS. 16, 17, 24, and the like, has a die 121 for
receiving the sheet material W pressed by the punch 115, a die
holder (die hold body) 125 for supporting a lower part of the die
121, and an upper press die (an end face pressing upper press die;
a die holder support member) 127.
[0082] The die holder 125 is integrally provided with the die 121
and upper press die 127. The die-side member 111 is attached to a
base frame 123 that is fixed to the lower base 107b (a lower table
159) of the apparatus base 107. Namely, the die-side member 111
(the die holder 125, die 121, and upper press die 127) is supported
by the base frame 123 and is vertically movable relative to the
base frame 123.
[0083] The die-side member 111 is upwardly pushed by a push member
such as a cylinder (for example, a pneumatic cylinder) 129. When
compressed air is fed into a lower cylinder chamber of the
pneumatic cylinder 129, the die-side member 111 ascends as
illustrated in FIG. 17. If pressure of the compressed air fed into
the pneumatic cylinder 129 is constant, the die-side member 111 is
always pushed upward under the constant pushing force without
regard to the position thereof.
[0084] When the compressed air into the lower cylinder chamber of
the pneumatic cylinder 129 is stopped, i.e. when the lower cylinder
chamber and an upper cylinder chamber of the pneumatic cylinder 129
are opened to the atmosphere, the die-side member 111 descends due
to its own weight.
[0085] The die-side member 111 may forcibly be lowered by feeding
compressed air into the upper cylinder chamber of the pneumatic
cylinder 129 and opening the lower cylinder chamber to the
atmosphere.
[0086] Instead of the cylinder, a resilient body such as a
compression coil spring may be employed to upwardly bias the
die-side member 111 like the bending apparatus 1 of the first
embodiment. It is possible that the bending apparatus 1 of the
first embodiment employs a cylinder to upwardly bias the die-side
member 12.
[0087] Instead of the cylinder or the resilient body such as the
compression coil spring, an actuator such as a servo motor may be
employed to vertically move and optionally position the die holder
125 and end face biasing upper press die 127.
[0088] The bending part 103 bends the sheet material W into, for
example, a V-shape and the bending of the sheet material W is
conducted along a pressing center 131 (refer to FIG. 24 and the
like) of the punch 115 and die 121.
[0089] The end face pressing part 105 has an end face pressing
lower press die (a lower press die) 135 arranged to face the upper
press die 127. The lower press die 135 presses the end face of the
sheet material W along a bend line of the sheet material W to be
bent.
[0090] The end face side of the sheet material W is placed on the
end face pressing lower press die 135. In this state, the punch 115
is moved (downward) toward the die 121 to move the die holder 125
and upper press die 127 in the same direction. Due to this
movement, the sheet material W is held between the upper press die
127 and the lower press die 135 and the end face of the sheet
material W is pressed (refer to FIG. 19).
[0091] The lower press die 135 is divided into a plurality of press
dies 137 (137A, 137B, 137C) and 139 (139A, 139B, 139C, 139D, 139E,
139F) (refer to FIG. 15 and the like) to press the end face of the
sheet material W against the die-side member 111 (the upper press
die 127), in corporation with the end face pressing upper press die
127 of the die-side member 111.
[0092] Among the divided press dies 137 and 139, the press dies
137A, 137B, and 137C, for example, are able to selectively press
(pressurize) the sheet material W against the die-side member
111.
[0093] The selective pressing is carried out to secure pressing
force of the end face pressing part 105 applied to the sheet
material W even when pressing force (pressurizing force) of the
bending driver 113 is insufficient.
[0094] In more detail, pressing the end face of the sheet material
W by the end face pressing part 105 (in a thickness direction of
the sheet material W) is carried out by using pressing force of the
bending apparatus 101 (the hydraulic cylinder 163 of the bending
driver 113). It is assumed that the end face pressing lower press
die 135 is divided into three press dies (a first press die 137A, a
second press die 137B, and a third press die 137C) (refer to FIGS.
13 and 15).
[0095] The length of the first press die (divided die) 137A (the
length including the press dies 139A and 139B), the length of the
second press die 137B (the length including the press dies 139C and
139D), and the length of the third press die 137C (the length
including the press dies 139E and 139F) are equal to one another
and are each about 500 mm. The first to third press dies 137A,
137B, and 137C are connected to each other in the length direction
to make the length (in the left-right direction) of the end face
pressing lower press die 135 to 1500 mm. The lengths of the press
dies (divided dies) 139A to 139F are equal to one another and are
each about 50 mm, which is sufficiently shorter than the length of
the press die 137.
[0096] The length of an end face of the sheet material W along a
bend line is slightly shorter than 1500 mm. A 500-millimeter end
part of the end face having the length slightly shorter than 1500
mm of the sheet material W is pressed by the press die 137A and
press dies 139A and 139B (the press dies 139C to 139F can be
included in some case). Similarly, a 500-millimeter central part of
the end face is pressed by the second press die 137B and the
500-millimeter remaining part thereof is pressed by the third press
die 137C.
[0097] The bending apparatus 101 (bending driver 113) is supposed
to have a maximum pressing force of 50 t (50000 kgf; about 500 kN).
It is supposed that a pressing force of 60 t, which is greater than
the maximum pressing force of 50 t, is required if simultaneously
pressing the end face of the sheet material W (made of, for
example, SPCC) having the length slightly shorter than 1500 mm
along the bend line with the use of the first to third press dies
137A to 137C and the press dies 139A to 139F to contain a boat warp
caused when bending the sheet material within an allowable
range.
[0098] In this case, the first press die 137A is first selected and
the 500-millimeter end part of the sheet material W is pressed only
by the first press die 137A (including the press dies 139A to 139F)
under a pressing force of about 20 t. Thereafter, the second press
die 137B is selected and the 500-millimeter central part of the
sheet material W is pressed only by the second press die 137B
(including the press dies 139A to 139F) under a pressing force of
about 20 t. Thereafter, the third press die 137C is selected and
the 500-mm remaining part of the sheet material W is pressed only
by the third press die 137C (including the press dies 139A to 139F)
under a pressing force of about 20 t.
[0099] The selection mentioned above is realized by separately
moving the press dies 137 and 139 in a direction (an orthogonal
direction; a front-rear direction) intersecting with the driving
(moving) direction (the direction to press the sheet material W; a
vertical direction) in which the punch-side member 109 (punch 115)
is moved toward the die-side member 111 (die 121).
[0100] If, for example, the press die 137 is moved backward, the
press die 137 comes obliquely under the punch-side member 109
(punch 115) as illustrated in FIG. 20. If the upper press die 127
descends in this state, the sheet material W is not held between or
not pressed by the upper press die 127 and press die 137.
[0101] If the press die 137 is moved forward, the press die 137
comes just under the punch-side member 109 (punch 115) as
illustrated in FIG. 19. If the upper press die 127 is lowered in
this state, the sheet material W is held between and pressed by the
upper press die 127 and press die 137.
[0102] The press die 137A illustrated in FIG. 15 is divided into a
plurality of (for example, three) press dies. These press dies are
connected together with a connection member 141 (141A) and are
moved in the front-rear direction by an actuator such as a
pneumatic cylinder (not illustrated). Similarly, press dies 137B
are connected together with a connection member 141 (141B) and are
moved in the front-rear direction. Also, press dies 137C are
connected together with a connection member 141 (141C) and are
moved in the front-rear direction.
[0103] Among the press dies 137 and 139, the press dies (stopper
supports) 139 (139A to 139F illustrated in FIG. 15) are moved and
positioned in the front-rear direction by a back gauge 143 of the
bending apparatus 101 (refer to FIGS. 13 and 14).
[0104] The press die 139 has a stopper (contact bar) 145 to which
the sheet material W is pushed (brought into contact) (refer to
FIG. 18 and the like). An end face of the sheet material W is
pressed to position the sheet material W and determine a pressing
width (a dimension L1 in FIG. 19) of the sheet material W to be
pressed by the end face pressing part 105.
[0105] The bending apparatus 101 has, for example, two back gauges
143 that are separately moved and positioned.
[0106] There are arranged at least two (six in FIG. 15) stopper
supports (press dies) 139. Among the plurality of stopper supports
139, two are in integrated with the two back gauges 143,
respectively.
[0107] The stopper supports 139 to be engaged with the back gauges
143 are properly selected according to the length of an edge of the
sheet material W in a length direction of the bend line along which
the punch 115 and die 121 bend the sheet material W.
[0108] The two stopper supports 139 engaged with the two back
gauges 143 are separately moved and positioned with the respective
back gauges 143 in the front-rear direction.
[0109] As is already understood, the stopper supports 139, stoppers
145, back gauges 143, and the like form the pressing width
adjusting mechanism of the bending apparatus 101.
[0110] The bending apparatus 1 according to the first embodiment
similarly uses back gauges to position the press dies (stopper
supports; contact bar supports).
[0111] The stopper 145 appears and disappears from a face (sheet
material pressing face) 149 of the stopper support 139 that presses
the sheet material W. The stopper 145 is pushed by a resilient body
such as a compression coil spring 151 so that the stopper 145
protrudes upward from the sheet material press face 149. When the
sheet material W is positioned, the stopper 145 protrudes upward
from the sheet material press face 149. When the sheet material W
is pressed by the end face pressing upper press die 127 and end
face pressing lower press die 135, the stopper 145 is pushed by the
end face pressing upper press die 127 and is moved into the stopper
support 139 (the press die of the end face pressing lower press die
135).
[0112] The bending apparatus 101 (also the bending apparatus 1 of
the first embodiment) has a hemming part 153 to hem the sheet
material W (refer to FIGS. 22 and 23).
[0113] The hemming part 153 is included by (serves also as) the end
face pressing part 105.
[0114] The die-side member 111 having the die holder 125 and upper
press die 127, the base frame 123, the lower press die 135, and the
like form a die setting body (die setter) 155.
[0115] As is already understood, the die setting body 155 is
installed on and used by the bending apparatus 101 (also the
bending apparatus 1 of the first embodiment) that employs the punch
115 and die 121 to carry out a bending process and the like on the
sheet material W.
[0116] The die setting body 155 has a die setting part 157, the end
face pressing part 105, and the hemming part 153. On the die
setting part 157, the die 121 is arranged. It may be configured to
set the punch 115 instead of the die 121.
[0117] As mentioned above, the end face pressing part 105 presses
the end face of the sheet material W along a bend line before the
sheet material W is bent by the punch 115 and the die 121 set on
the die setting part 157.
[0118] The end face pressing part 105 is divided into the plurality
of press dies 137 and 139 in the extending direction of the bend
line along which the sheet material W is bent. When pressing the
end face of the sheet material W along the bend line, the divide
press dies 137 are selectively used.
[0119] As mentioned above, the press die 139 having the stopper 145
is moved and positioned by the back gauge 143 of the bending
apparatus 101.
[0120] In FIG. 15, three die setting bodies 155A, 155B, and 155C
are connected to one another in a longitudinal direction. The die
setting body 155 illustrated in FIG. 15 is installed on the bending
apparatus 101.
[0121] The bending apparatus 101, die setting body 155, and the
like will be explained in more detail.
[0122] For the sake of explanation, a horizontal direction
(left-right direction) is set as an X-axis direction, another
horizontal direction (front-rear direction) orthogonal to the
X-axis direction as a Y-axis direction, and a direction (top-bottom
direction) orthogonal to the X- and Y-axis directions as a Z-axis
direction.
[0123] As illustrated in FIGS. 13 and 14, the lower table 159 is
integrally arranged at a front lower part of the apparatus base
(frame) 107 of the bending apparatus 101. On a top face of the
lower table 159, the die setting body 155 (155A, 155B, 155C) are
successively connected in the longitudinal direction and extending
in the X-axis direction (refer to FIGS. 13 and 15).
[0124] Above the die setting body 155 (155A, 155B, 155C), the die
121 (121A, 121B, 121C) is integrally arranged. The dies 121A, 121B,
and 121C have the same specifications and are successively
connected in the longitudinal direction and extending in the X-axis
direction.
[0125] At a front upper part of the apparatus base 107, the upper
table 119 is arranged. The upper table 119 is movable in the Z-axis
direction relative to the apparatus base 107.
[0126] Integrally arranged through the punch holder 117 on lower
face of the upper table 119 is the punch 115 (115A, 115B, 115C).
The punches 115A, 115B, and 115C have the same specifications and
are successively connected in the longitudinal direction and
extending in the X-axis direction (refer to FIG. 13).
[0127] The punches 115A, 115B, and 115C arranged on the upper table
119 face the dies 121A, 121B, and 121C arranged on the lower table
159, respectively.
[0128] The bending apparatus 101 (bending apparatus 1) is provided
with a controller 161. Under the control of the controller 161, the
upper table 119 is moved and positioned in the Z-axis direction by
the hydraulic cylinder 163 of the bending driver 113.
[0129] With this, the bending part 103 bends the sheet material W,
the end face pressing part 105 presses an end face of the sheet
material W, and the hemming part 153 hems the sheet material W.
[0130] The back gauge 143 is arranged at a central part of the
apparatus base 107 in the Z-axis direction and behind the lower
table 159 in the Y-axis direction. Under the control of the
controller 161, the back gauge 143 is moved and positioned in the
X-, Y-, and Z-axis directions with respect to the apparatus base
107.
[0131] The die setting body 155A will be explained in detail. The
die setting bodies 155B and 155C are configured similar to the die
setting body 155A, and therefore, explanations thereof are
omitted.
[0132] As illustrated in FIGS. 17, 21, and the like, the die
setting body 155A has the base frame 123, die holder 125, upper
press die 127, cylinder 129, lower press die 135 (press dies 137
and 139), connection member 141, and stopper 145.
[0133] The base frame 123 has a thin and long parallelepiped shape.
More precisely, a section (a sectional plane orthogonal to the
longitudinal direction, i.e., the X-axis direction) of the base
frame 123 has a rectangular lower base part 165 and a rectangular
upper joint part 167.
[0134] A width (a dimension in the Y-axis direction) of the upper
joint part 167 is smaller than a width (a dimension in the Y-axis
direction) of the lower base part 165. The upper joint part 167 is
positioned at an intermediate part of the lower base part 165 in
the Y-axis direction and upwardly protrudes from an upper end of
the lower base part 165 in the Z-axis direction.
[0135] The die holder 125 is formed in a thin and long
parallelepiped shape having the same length as the base frame 123
and is positioned at the same location as the base frame 123 in the
X-axis direction (longitudinal direction). More precisely, a
section (a sectional plane normal to the longitudinal direction) of
the die holder 125 has a rectangular upper body part 169 and a
rectangular lower protrusion part 171.
[0136] A width value (a dimension in the Y-axis direction) of the
lower protrusion part 171 is smaller than a width value (a
dimension in the Y-axis direction) of the upper body part 169. The
lower protrusion part 171 is positioned at a rear end of the upper
body part 169 in the Y-axis direction and protrudes from a lower
end of the upper body part 169 in the Z-axis direction.
[0137] The die holder 125 has a die setting recess (die) setting
groove) 173. The die setting recess 173 is formed along the hole
length of the die holder 125 in the longitudinal direction (X-axis
direction). When the die holder 125 is sectioned, a width value of
the die setting recess 173 is smaller than a width value of the
upper body part 169 and a depth value (a dimension in the Z-axis
direction) thereof is smaller than a height value (a dimension in
the Z-axis direction) of the upper body part 169. The die setting
recess 173 is positioned at an intermediate part of the upper body
part 169 in the Y-axis direction and downwardly recessed in the
Z-axis direction from an upper end of the upper body part 169.
[0138] A lower part of the die 121 is in the die setting recess 173
so that the die 121 is integrally arranged on the die holder 125. A
length (a dimension in the X-axis direction) of the die 121 is
equal to the length of the base frame 123 and is positioned at the
same location as the base frame 123 in the X-axis direction
(longitudinal direction).
[0139] The upper press die 127 has a thin and long parallelepiped
shape having the same length as the base frame 123 and is
positioned at the same location as the base frame 123 in the X-axis
direction (longitudinal direction). More precisely, a section (a
sectional plane orthogonal to the longitudinal direction) of the
upper press die 127 has a rectangular upper recess 175 and a
triangular lower chamfered part 177 to generally form an
L-shape.
[0140] The upper recess 175 and lower chamfered part 177 extend
along the hole length of the upper press die 127 in the
longitudinal direction (X-axis direction). When the upper press die
127 is sectioned, a width value of the upper recess 175 is smaller
than a width value of the upper press die 127 and a depth value (a
dimension in the Z-axis direction) thereof is smaller than a height
value (a dimension in the Z-axis direction) of the upper press die
127. The upper recess 175 is arranged at a rear upper corner of the
upper press die 127. The lower chamfered part 177 is arranged at a
front lower corner of the upper press die 127.
[0141] Two faces (sides) of the upper press die 127 that form a
front lower corner of the upper body part 169 of the die holder 125
are in the upper recess 175. The two faces of the upper recess 175,
i.e., a plain spreading in the X- and Y-axis directions and a plain
spreading in the X- and Z-axis directions are in face-to-face
contact with front and lower faces of the upper body part 169,
respectively. In this way, the upper press die 127 is integrated
with the die holder 125.
[0142] The die holder 125 and the upper press die 127 arranged
thereon define a thin and long parallelepiped groove 179 at a lower
central part thereof.
[0143] This groove 179 receives the upper joint part 167 of the
base frame 123 so that the base frame 123 engages with the die
holder 125 and upper press die 127. With this, the base frame 123
and the die holder 125 and upper press die 127 form a sliding pair
so that the die holder 125 and upper press die 127 move in the
Z-axis direction relative to the base frame 123.
[0144] A width (a dimension in the Y-axis direction) of the groove
179 is set to be slightly larger than a width (a dimension in the
Y-axis direction) of the upper joint part 167 of the base frame
123.
[0145] The base frame 123 incorporates the cylinder 129. The
cylinder 129 has a cylinder body 181, a piston 183, and a piston
rod 185.
[0146] The cylinder 129 is at a central part of the base frame 123
in the Y-axis direction. In the Z-axis direction, the cylinder body
181 and piston 183 are positioned at a lower part and the piston
rod 185 upwardly protrudes. A front end of the piston rod 185
protrudes from an upper end of the base frame 123 (the upper joint
part 167) and integrally engages with the upper body part 169 of
the die holder 125. The cylinder body 181 is integral with the base
frame 123.
[0147] When the upper cylinder chamber of the piston 183 is opened
to the atmosphere and compressed air is fed into the lower cylinder
chamber of the piston 183, the die holder 125, upper press die 127,
and die 121 are positioned to a lifted end as illustrated in FIGS.
17, 18, 21, and 22.
[0148] When the upper and lower cylinder chambers of the piston 183
are opened to the atmosphere, the die holder 125, upper press die
127, and die 121 descend due to, for example, their own weights
(refer to FIGS. 19, 20, 24, and the like).
[0149] The press die 137 (137A) of the lower press die 135 has a
thin and long parallelepiped shape. More precisely, as illustrated
in FIG. 17, a sectional shape (a sectional plane normal to the
longitudinal direction) of the press die 137 is substantially
rectangular having an upper front cut 187.
[0150] At a front upper part of the lower base part 165 of the base
frame 123, there is a recess 189. In a sectional shape of the base
frame 123, the recess 189 is rectangular as illustrated in FIG. 17
and is formed at a front upper corner of the lower base part 165 of
the base frame 123.
[0151] The press die 137 is in the recess 189. A lower face of the
press die 137 and a bottom face of the recess 189 are in
face-to-face contact with each other. The press die 137 is moved by
an actuator such as a pneumatic cylinder (not illustrated) in the
Y-axis direction relative to the base frame 123.
[0152] In FIGS. 17, 19, 22, 23, and 24, the press die 137 is at a
front movable end, and in FIG. 20, the press die 137 is at a rear
movable end.
[0153] As illustrated in FIG. 18, the press die 139 (139A, 139B) of
the lower press die 135 has a sectional shape (a sectional plane
normal to the X-axis direction) of L having a lower horizontal part
191 and an upper upright part 193.
[0154] A height dimension (a dimension in the Z-axis direction) of
the lower horizontal part 191 is equal to a height dimension of the
press die 137. Formed at a front upper part of the lower horizontal
part 191 is a cut 195 that is similar to the cut 187.
[0155] Formed at an upper part of the lower base part 165 and a
lower part of the upper joint part 167 of the base frame 123 is a
through hole 197 passing through the base frame 123 in the
front-rear direction. A height position of a bottom face of the
through hole 197 agrees with a height position of a bottom face of
the recess 189.
[0156] The press die 139 arranged in the through hole 197 has a
lower face that is in face-to-face contact with the bottom face of
the through hole 197 to form a sliding pair.
[0157] Accordingly, when the press dies 137 and 139 are arranged on
the base frame 123, the position of an upper face 203 of the press
die 137 agrees in the Z-axis direction with the position of an
upper face 201 of the lower horizontal part 191 of the press die
139.
[0158] The upper upright part 193 of the press die 139 is
integrally engaged with the back gauge 143, and therefore, the
press die 139 is able to be moved and positioned in the Y-axis
direction.
[0159] The lower horizontal part 191 of the press die 139 is
provided with the stopper 145. The stopper 145 is vertically
movable with respect to the lower horizontal part 191 and is able
to appear and disappear from the upper face 201 of the lower
horizontal part 191.
[0160] The stopper 145 is upwardly biased by the compression coil
spring 151. If no external force is applied, the stopper 145
protrudes from the upper face 201 of the lower horizontal part 191
(refer to FIG. 18). When the punch 115 is lowered, the stopper 145
is pushed by the upper press die 127 and is downwardly moved (refer
to FIG. 19 and the like).
[0161] To press the sheet material W to reduce a boat warp or to
bend the sheet material W, the press die 139 (139A to 139F) is
positioned in the Y-axis direction as illustrated in FIG. 18.
Namely, the stopper 145 is backwardly spaced by a proper dimension
L1 from a front end of a lower face 199 of the upper press die 127.
The dimension L1 is a pressing width of the sheet material W.
[0162] To carry out a hemming process, the press die 139 is
positioned at a rear end as illustrated in FIG. 21. At this time,
the stopper 145 is in the through hole 197 of the base frame
123.
[0163] In each of the cases illustrated in FIGS. 18 and 21, the
upper face 201 of the lower horizontal part 191 of the press die
139 partly holds and presses the sheet material W, and therefore,
faces the lower face 199 of the upper press die 127.
[0164] In the die setting body 155A, the press dies 137A, 139A,
137A, 139B, and 137A are arranged in this order from the left to
the right in the X-axis direction.
[0165] As illustrated in FIG. 13, the die setting bodies 155A,
155B, and 155C are arranged in this order from the left to the
right in the X-axis direction. Then, from the left to the right,
the press dies 137A, 139A, 137A, 139B, 137A, 137B, 139C, 137B,
139D, 137B, 137C, 139E, 137C, 139F, and 137C are arranged in this
order (refer to FIG. 15).
[0166] Illustrated with a reference numeral 205 in FIG. 17 is a
guide plate for guiding the sheet material W. The guide plate 205
is integrally arranged with the base frame 123 through the
connection member 141.
[0167] Protruding from a lower end of the base frame 123 is an
engagement pin 207. With the engagement pin 207 and fastening tools
such as bolts, the base frame 123 (the die setting body 155) is
integrally installed on the upper face of the lower table 159.
[0168] As is already understood, the punch 115 and the die 121 set
on the die setting body 155 form the bending part 103. The upper
press die 127 (lower face 199) of the die setting body 155 and the
lower press die 135 (upper faces 201 and 203) of the die setting
body 155 form the end face pressing part 105 and hemming part
153.
[0169] Operation of the bending apparatus 101 will be
explained.
[0170] The length in the X-axis direction of the die setting bodies
155A, 155B, and 155C is supposed to be 1500 mm (500 mm.times.3).
This means that the die 121 and punch 115 are able to bend the
sheet material W at one time for a length of 1500 mm at the
maximum. The length of a bend line of the sheet material W is
supposed to be slightly shorter than 1500 mm.
[0171] First, a pressing operation for relaxing a boat warp of the
sheet material W and a bending operation for bending the sheet
material W will be explained.
[0172] In an initial state illustrated in FIGS. 17 and 18, the
punch 115 is lifted, the die holder 125 and upper press die 127 are
positioned at a lifted end, the press die 139 of the die setting
body 155A, the press die 139 of the die setting body 155B, and the
press die 139 of the die setting body 155C are positioned as
illustrated in FIG. 18, the press die 137A of the die setting body
155A is forwardly positioned as illustrated in FIG. 17, and the
press die 137B of the die setting body 155B and the press die 137C
of the die setting body 155C are backwardly positioned as
illustrated in FIG. 20.
[0173] In this initial state, the sheet material W is set on the
die setting body 155 (155A to 155C). In this state, the die setting
body 155 (155A to 155C) and sheet material W positionally agree
with each other in the X-axis direction. As illustrated in FIGS. 17
and 18, the sheet material W is in contact with the stoppers 145
and is thereby positioned in the Y-axis direction.
[0174] The punch 115 is lowered so that the upper press die 127 of
the die setting body 155A and the lower press die 135 (the press
dies 137A, 139A, and 139B) of the die setting body 155A press a
longitudinal end of the sheet material W for a width L1 (refer to
FIG. 19).
[0175] At this time, the upper press die 127 of the die setting
body 155B and the press dies 139C and 139D of the die setting body
155B, as well as the upper press die 127 of the die setting body
155C and the press dies 139E and 139F of the die setting body 155C
press the sheet material W similarly.
[0176] Thereafter, the punch 115, die holder 125, and upper press
die 127 are positioned to a lifted end, the press die 137A of the
die setting body 155A is positioned rearward as illustrated in FIG.
20, and the press die 137B of the die setting body 155B is
positioned forward as illustrated in FIG. 19.
[0177] Thereafter, the punch 115 is lowered so that the upper press
die 127 of the die setting body 155B and the lower press die 135
(the press dies 137B, 139C, and 139D) of the die setting body 155B
press a longitudinal central part of the sheet material W for the
width L1 (refer to FIG. 19).
[0178] At this time, the upper press die 127 of the die setting
body 155A and the press dies 139A and 139B of the die setting body
155A, as well as the upper press die 127 of the die setting body
155C and the press dies 139E and 139F of the die setting body 155C
press the sheet material W similarly.
[0179] Thereafter, the punch 115, die holder 125, and upper press
die 127 are positioned to the lifted end, the press die 137 of the
die setting body 155B is positioned rearward as illustrated in FIG.
20, and the press die 137 of the die setting body 155C is
positioned forward as illustrated in FIG. 19.
[0180] Thereafter, the punch 115 is lowered so that the upper press
die 127 of the die setting body 155C and the lower press die 135
(the press dies 137C, 139E, and 139F) of the die setting body 155C
press the other longitudinal end of the sheet material W for the
width L1 (refer to FIG. 19).
[0181] At this time, the upper press die 127 of the die setting
body 155A and the press dies 139A and 139B of the die setting body
155A, as well as the upper press die 127 of the die setting body
155B and the press dies 139C and 139D of the die setting body 155B
press the sheet material W similarly.
[0182] This completes the pressing of the sheet material W for the
full length of 1500 mm, i.e. for relaxing a boat warp of the sheet
material W.
[0183] Thereafter, the punch 115, die holder 125, and upper press
die 127 are positioned to the lifted end, the sheet material W is
taken out of the die setting body 155, and the die holder 125 and
upper press die 127 are positioned to a lowered end as illustrated
in FIG. 24. When the die holder 125 and upper press die 127 are at
the lowered end, a gap between the lower face 199 of the upper
press die 127 and the upper faces 201 and 203 of the lower press
die 135 is very small (about 0.2 mm) as illustrated in FIG. 25.
[0184] This prevents foreign matter such as dust from entering
between the lower face 199 of the upper press die 127 and the upper
faces 201 and 203 of the lower press die 135, so that the sheet
material W is precisely bent.
[0185] When the die holder 125 and upper press die 127 are
positioned at the lowered end, an upper face of the upper joint
part 167 of the base frame 123 and a lower face of the upper body
part 169 of the die holder 125 are in face-to-face contact with
each other.
[0186] Thereafter, the sheet material W is set on the die 121 and
the punch 115 is lowered to bend the sheet material W for nearly
the whole length of 1500 mm at one time.
[0187] A hemming operation of the sheet material W will be
explained.
[0188] In an initial state illustrated in FIG. 21, the punch 115 is
lifted, the die holder 125 and upper press die 127 are positioned
to the lifted end, the press die 139 of the die setting body 155A,
the press die 139 of the die setting body 155B, and the press die
139 of the die setting body 155C are positioned to the rear end,
and the press die 137A of the die setting body 155A, the press die
137B of the die setting body 155B, and the press die 137C of the
die setting body 155C are positioned forward.
[0189] In this initial state, the punch 115 is lowered to bend the
sheet material W as illustrated in FIG. 24. This bending is carried
out at once for the length of about 1500 mm. An angle of the
bending is about 30 degrees.
[0190] Thereafter, the punch 115 is lifted, the die holder 125 and
upper press die 127 are positioned to the lifted end, and the part
of the sheet material W bent by about 30 degrees is set between the
upper press die 127 and the lower press die 135 (refer to FIG.
22).
[0191] Thereafter, the punch 115 is lowered so that the upper press
die 127 and lower press die 135 hold the part of the sheet material
W bent by about 30 degrees and the hemming process is carried out
(refer to FIG. 23).
[0192] When hemming the sheet material W, the state illustrated in
FIG. 22 and the state illustrated in FIG. 23 have the left end of
the sheet material W set at the same position. To reduce moment
generated on the die setting body 155, the position of the stopper
145 may properly be changed to change the left end position of the
sheet material W that is brought into contact with the stopper 145
(refer to, for example, Japanese Unexamined Patent Application
Publication No. 2003-181546).
[0193] In the above explanation, the three punches 115 have the
same specifications and the three dies 121 also have the same
specifications. The punches 115 and dies 121 may have different
specifications. However, the heights of the dies (a pass line of
the sheet material W) must be equal to one another.
[0194] Each die setting body 155 may differently process the sheet
material W.
[0195] For example, the die setting body 155A hems the sheet
material W and the die setting bodies 155B and 155C press and bend
the sheet material W.
[0196] This enables the sheet material W to be differently
processed, for example, bent, hemmed, and the like without changing
arrangements.
[0197] According to the bending apparatus 101, the press dies 137
and 139 are able to selectively press the sheet material W so that,
without increasing the maximum pressing force of the bending driver
113, a sufficient pressing force is applicable to the sheet
material W and a boat warp occurring on the sheet material W during
bending can easily be contained within an allowable range.
Accordingly, without using a large bending apparatus having a
maximum thrust required, a sufficient pressing force is applicable
to the sheet material W.
[0198] The bending apparatus 101 realizes such selective pressing
by individually moving the press dies 137 and 139 in the front-rear
direction to achieve the selective pressing. This configuration is
simple to select proper ones from among the press dies and press a
sheet material.
[0199] According to the bending apparatus 101, the simple structure
using the back gauge 143 can set an area (a width, i.e., the
dimension L1 in FIGS. 18 and 19) of the sheet material W to press
without using separate mechanisms or actuators.
[0200] According to the bending apparatus 101, the hemming part 153
is made of the end face pressing part 105, and therefore, is able
to hem the sheet material W with a simple configuration without
preparing a separate hemming part.
Third Embodiment
[0201] A bending apparatus (a brake press; a sheet material
processing apparatus) 301 according to the third embodiment differs
from the bending apparatus 1 of the first embodiment or the bending
apparatus 101 of the second embodiment in that the third embodiment
employs a press die 303, which is not used for bending a sheet
material W, to (i) press an end part of the sheet material W for
such as adjusting residual stress caused when cutting the sheet
material W or reducing a warp to be caused when bending the sheet
material W and to (ii) hem (if required) the end part of the sheet
material W. The other parts of the bending apparatus 301 are
configured similar to the bending apparatuses 1 and 101, to provide
similar operations and similar effects.
[0202] The sheet material processing apparatus (processing
apparatus) 301 according to the third embodiment has an apparatus
base 302 (refer to FIG. 30(b)) similar to, for example, the
apparatus base 107 illustrated in FIG. 14. It also has a
pressurizing part (pressurizing means) 305 for pressurizing the
sheet material W and a supporting part (receiving means) 307 for
supporting the sheet material W pressurized by the pressurizing
part 305 (refer to FIGS. 26, 27, 29, and the like).
[0203] The processing apparatus 301 also has an end face pressing
upper press die 309, an end face pressing lower press die 311, an
end face pressing part 313, and an end face pressing width
adjusting part (end face pressing width adjusting mechanism)
315.
[0204] The end face pressing upper press die 309 is configured to
receive pressurizing force from the pressurizing part 305. The
pressurizing part 305 is made of an actuator such as a hydraulic
cylinder (similar to the hydraulic cylinder 163 of the processing
apparatus 101 of the second embodiment illustrated in, for example,
FIG. 13) arranged on an upper side of the apparatus base 302. The
supporting part 307 is formed by a lower part of the apparatus base
302.
[0205] The end face pressing lower press die 311 is arranged on the
supporting part 307 side (lower side) and faces the end face
pressing upper press die 309. Between the end face pressing lower
press die 311 and the end face pressing upper press die 309, an end
face of the sheet material W is inserted.
[0206] In the end face pressing part 313, the pressurizing part 305
provides a pressurizing force to move the end face pressing upper
press die 309 toward the end face pressing lower press die 311.
When the end face pressing upper press die 309 is lowered, one end
face 319 of the sheet material W to be processed (to be bent) is
pressed (pressurized) along a bend line of the she t material V
(refer to FIGS. 27, 30, and the like). Namely, between the end face
pressing upper press die 309 and the end face pressing lower press
die 311, i.e., between the pressurizing part 305 and the supporting
part 307 in the end face pressing part 313, the sheet material W is
held by the end face pressing upper press die 309 and end face
pressing lower press die 311 so that the end of the sheet material
W is pressed in a thickness direction.
[0207] When the sheet material W is pressed by the end face
pressing part 313, the end face pressing width adjusting part 315
sets a pressing width (a dimension in the Y-axis direction) at the
end face 319 of the sheet material W. With this, the contact face
(stopped face) 319 of the sheet material W is positioned in front
of (opposite to the C-shaped apparatus base 302) a pressurizing
center (pressing center) 317 of the pressurizing force applied by
the pressurizing part 305 to the end face pressing upper press die
309, in terms of an insertion direction (a left-to-right direction
in FIG. 30, i.e., a front-to-rear direction in the Y-axis
direction) in which the sheet material W is inserted into between
the end face pressing upper press die 309 and the end face pressing
lower press die 311 (refer to FIG. 30(b)). Namely, the stopped face
319 of the sheet material W is slightly in front of the
pressurizing center 317 in the Y-axis direction and the whole of
the sheet material W is positioned in front of the stopped face 319
in the Y-axis direction.
[0208] Similar to the processing apparatus 101 of the second
embodiment, the end face pressing lower press die 311 is divided in
the X-axis direction into a plurality of press dies 321 (321A to
321I) that are able to press the end of the sheet material W
against the end face pressing upper press die 309 (refer to FIG. 26
and the like).
[0209] These divided press dies 321 are configured to be
selectively used (to realize selective press) when pressing the end
face 319 of the sheet material W.
[0210] To achieve such selection, each of the press dies 321 is
moved in a direction (Y-axis direction) intersecting with a driving
direction (Z-axis direction) in which the end face pressing upper
press die 309 is driven toward the end face pressing lower press
die 311.
[0211] The end face pressing width adjusting part 315 is a press
die (321B, 321D, 321F, 321H) among the press dies 321, is moved and
positioned in the above-mentioned intersecting direction (Y-axis
direction) by a back gauge (not illustrated in FIGS. 26 to 30) of
the processing apparatus 301, and is provided with a stopper
(contact bar) 323 which is arranged on the press die and to which
the sheet material W is pushed.
[0212] The press dies 321A, 321C, 321E, 321G, and 321I are moved in
the Y-axis direction by an actuator such as a pneumatic cylinder
(not illustrated).
[0213] Similar to the processing apparatus 101 of the second
embodiment, the stopper 323 is biased upward by a compression coil
spring 325 (refer to FIG. 29).
[0214] The processing apparatus 301 also has a hemming part 327
(refer to FIG. 28) for hemming an end of the sheet material W. The
hemming part 327 is included by the end face pressing part 313.
[0215] As is already understood, the end face pressing upper press
die 309, end face pressing lower press die 311, end face pressing
part 313, and end face pressing width adjusting part 315 form the
press die 303 that is arranged on and used by the processing
apparatus (for example, press brake) 301.
[0216] The processing apparatus 301 employs a punch, a die, and the
pressurizing part 305 to bend the sheet material W. When the press
die 303 is used to press the sheet material W without bending the
sheet material W, the punch and die are not used. Instead, the end
face pressing upper press die 309 having a flat lower face is used
for the punch and the end face pressing lower press die 311 having
a flat upper face is used for the die, as illustrated in FIG.
26.
[0217] As mentioned above, the end face pressing lower press die
311 of the press die 303 is divided in the X-axis direction into
the plurality of press dies 321 (321A to 321I). When pressing the
end face 319 of the sheet material W along a bend line, the divided
press dies 321 are selectively used. Each of the press dies 321 is
movable in the Y-axis direction to realize such selection. Among
the press dies 321, those provided with the stoppers 323 are moved
and positioned in the Y-axis direction by the back gauge of the
processing apparatus 301.
[0218] The press die 303 also has the hemming part 327 that is
formed by the end face pressing part 313.
[0219] According to the processing apparatus 301, the end face
pressing part 313 presses the sheet material W. At this time, the
end face 319 of the sheet material W and the whole of the sheet
material W are positioned opposite to the C-shaped apparatus base
302 (refer to FIG. 30). Accordingly, the sheet material W is surely
pressed to reduce a warp to be caused when the sheet material W is
bent.
[0220] As illustrated in FIG. 30(a), the end face 319 of the sheet
material is pressed. At this time, the sheet material W is
positioned opposite to the C-shaped apparatus base 302 with respect
to the pressing center 317. The apparatus base 302 and the like are
not perfect rigid bodies. Due to this, moment (refer to an arrow MT
in FIG. 30) occurs on the end face pressing upper press die 309
(end face pressing lower press die 311), to cause a slight
resilient deformation (deflection) on the apparatus base 302 and
the like, thereby slightly inclining the end face pressing upper
press die 309 (end face pressing lower press die 311) (refer to
FIG. 30(b)). In FIG. 30(b), the inclination of the end face press
die 309 is exaggerated.
[0221] Due to the slight inclination caused by the moment MT, the
end 319 of the sheet material W receives a maximum press force
larger than that applied to the remaining part of the sheet
material W. This correctly and surely presses the sheet material W
and surely reduces a boat warp to be caused when the sheet material
W is bent.
[0222] The stopper 323 provided for each of the press dies 321B,
321D, 321F, and 321H may be integrally formed on the press die so
that the stopper 323 is immovable in the Z-axis direction, the
heights of the stoppers 323 being equalized with one another.
[0223] In this case, the end face pressing upper press die 309 is
provided with a recess (not illustrated) to receive the stopper 222
to prevent the stopper 323 from interfering with the end face
pressing upper press die 309 when the press die 309 is lowered.
[0224] If the thickness of the sheet material W is larger than the
protruding height of the stopper 323, the end face pressing upper
press die 309 may not be provided with such a recess to receive the
stopper 323.
[0225] In addition, the press dies 321B, 321D, 321F, and 321H may
be fixed in the Y-axis direction.
[0226] At least one of the die setting bodies 121A, 121B, and 121C
illustrated in FIG. 13 may be replaced with the press die 303. In
this case, pass lines (die heights) of them all must be
equalized.
[0227] According to a technical aspect of the present invention, a
sheet material is correctly pressed to reduce a warp to be caused
when the sheet material is bent.
[0228] According to another technical aspect of the present
invention, a bending part for bending a sheet material and an end
face pressing part for pressing an end face of the sheet material
to suppress a warp of the sheet material are arranged on a single
apparatus. The single apparatus, therefore, is capable of carrying
out both the end face pressing and bending of a sheet material,
thereby realizing the easy handling of the sheet material and
improving workability.
(United States Designation)
[0229] In connection with United States designation, this
international patent application claims the benefit of priority
under 35 U.S.C. 119(a) to Japanese Patent Application No.
2011-242501 filed on Nov. 4, 2011 and Japanese Patent Application
No. 2012-226724 filed on Oct. 12, 2012, disclosed contents thereof
being cited herein.
* * * * *