U.S. patent application number 14/361674 was filed with the patent office on 2016-08-04 for dieless sheet forming apparatus with flexible rollers.
The applicant listed for this patent is PUSAN NATIONAL UNIVERSITY INDUSTRY-UNIVERSITY COOPERATION FOUNDATION. Invention is credited to Beom-Soo KANG, Jun-Seok YOON.
Application Number | 20160221053 14/361674 |
Document ID | / |
Family ID | 49456285 |
Filed Date | 2016-08-04 |
United States Patent
Application |
20160221053 |
Kind Code |
A1 |
KANG; Beom-Soo ; et
al. |
August 4, 2016 |
DIELESS SHEET FORMING APPARATUS WITH FLEXIBLE ROLLERS
Abstract
Disclosed is a dieless sheet forming device including: two
forming rollers rotatably disposed up and down to correspond with
each other and bent to various curvatures; and a plurality of
roller adjustment members whose one ends are fixed to each forming
roller in such a manner as to be adjusted in length to adjust the
curvatures of the forming rollers and the distances between the two
forming rollers, wherein the curvatures of the forming rollers and
the distances between the forming rollers through which a sheet to
be formed is passed are adjusted to change the forming shape of the
sheet. According to the present invention, the forming shapes of
the sheet can be easily corrected if the desired shape is changed,
so that the sheet forming device can be applied for small quantity
batch production, does not generate dimples or wrinkles, can form
even the edge portions of the sheet, and can form the sheet without
having the limitation on the thickness or size of the sheet.
Inventors: |
KANG; Beom-Soo; (Busan,
KR) ; YOON; Jun-Seok; (Gyeongsangnam-Do, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PUSAN NATIONAL UNIVERSITY INDUSTRY-UNIVERSITY COOPERATION
FOUNDATION |
Busan |
|
KR |
|
|
Family ID: |
49456285 |
Appl. No.: |
14/361674 |
Filed: |
August 27, 2013 |
PCT Filed: |
August 27, 2013 |
PCT NO: |
PCT/KR2013/007642 |
371 Date: |
May 29, 2014 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B21B 1/22 20130101; B21D
31/00 20130101; B21D 37/02 20130101; B21D 11/20 20130101; B21D 5/14
20130101 |
International
Class: |
B21B 1/22 20060101
B21B001/22 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 7, 2013 |
KR |
10-2013-0024711 |
Claims
1. A dieless sheet forming device comprising: two forming rollers
rotatably disposed up and down to correspond with each other and
bent to various curvatures; and a plurality of roller adjustment
members whose one ends are fixed to each forming roller in such a
manner as to be adjusted in length to adjust the curvatures of the
forming rollers and the distances between the two forming rollers,
wherein the curvatures of the forming rollers and the distances
between the forming rollers through which a sheet to be formed is
passed are adjusted by means of the roller adjustment members to
change the forming shape of the sheet.
2. The dieless sheet forming device according to claim 1, wherein
each roller adjustment member comprises an external member having
an internal screw thread and an internal member having an external
screw thread and is adjusted in length in accordance with the
screw-coupled length between the external member and the internal
member.
3. The dieless sheet forming device according to claim 2, wherein
the external member is fixed to one of the forming rollers, and the
internal member is connected to the motor, so that the length of
each roller adjustment member is adjusted through the rotation of
the motor.
4. The dieless sheet forming device according to claim 2, wherein
the external member is fixed to one of the forming rollers, and
each roller adjustment member has a roller guide disposed rotatably
at the end of the external member fixed to the forming roller, the
roller guide having a recess of a major arc shape, into which the
forming roller is fittedly inserted.
5. The dieless sheet forming device according to claim 1, wherein
the sheet to be formed is inserted between the two forming rollers
and pulled so as to be passed through between the forming rollers,
thus completing the forming of the sheet.
6. The dieless sheet forming device according to claim 1, wherein
one or both forming rollers are connected at both ends thereof to
roller rotation motors, so that the sheet engaged with the forming
rollers is pushed and formed through the rotation of the roller
rotation motors.
7. The dieless sheet forming device according to claim 1, wherein
each forming roller is wound by steel wires on the outer peripheral
surface.
8. The dieless sheet forming device according to claim 7, wherein
the steel wire wound on an outmost surface of each forming roller
contacted with the sheet becomes flat through grinding.
9. The dieless sheet forming device according to claim 7, wherein
the steel wire wound on an outmost surface of each forming roller
contacted with the sheet has an oval section.
Description
TECHNICAL FIELD
[0001] The present invention relates to a dieless sheet forming
device, and more particularly, to a dieless sheet forming device
that is provided with flexible forming rollers whose curvatures are
adjustable, thus being adequate for small quantity batch
production.
BACKGROUND ART
[0002] So as to form a thick or thin sheet, generally, upper and
lower dies 1 corresponding to a desired forming shape of a sheet 3
are made, as shown in FIG. 1, and after the sheet 3 is disposed
between the upper and lower dies 1, it is formed by means of a
press.
[0003] In this case, the conventional sheet forming device using
the dies can produce sheets having the same curved shapes as each
other in large quantities, but if a desired forming shape is
corrected or changed, new dies should be made, so that the die
designing cost and the production cost of the final product are all
increased, thus being not adequate for small quantity batch
production. Besides, even though the desired forming shape is not
corrected, additional costs for keeping, maintaining and discarding
the dies are needed when the dies are being not used temporarily or
permanently.
[0004] So as to solve the above-mentioned problems, accordingly,
there has been proposed Korean Patent Registration No. 10-1034592
wherein a multi-point sheet forming device includes an upper die
11a and a lower die 11b each having a plurality of punches movable
up and down independently of each other, as shown in FIG. 2. The
conventional multi-point sheet forming device adjusts the heights
of the punches formed on the upper die 11a and the lower die 11b if
a desired forming shape is corrected or changed, thus easily
changing the forming shape. However, irregular spaces are formed
between the sheet and the forming device due to the radius of
curvature of each punch head and the height difference between the
punches, which makes it hard to form the curved surface having
locally small radius of curvature or edge, and further, since the
edges of the sheet are not formed well, they cut to cause the sheet
material to be unnecessarily consumed. Moreover, if it is desired
to form a thin sheet, not a thick sheet, dimples or local wrinkles
occur in accordance with the sizes of the punches.
[0005] So as to solve the above-mentioned problems, accordingly,
elastic pads 25 made of for example an urethane material are
disposed between forming punches 21a and 21b and a sheet 23,
respectively, as shown in FIG. 3, but the lengths of the punches
should be readjusted in accordance with the materials of the
elastic pads 25 and desired forming shapes of the sheet 23, which
also decreases the operating efficiency of the device and the
forming precision of the sheet.
[0006] Further, the conventional die forming device and the
conventional multi-point forming device using the plurality of
punches are restricted in the size of the final forming shape in
accordance with the sizes of the dies, and so as to form a
large-sized sheet, therefore, the final forming shape is
sectionalized and formed. Next, the sectionalized forming shapes
are bonded through additional mechanical process and welding to
produce the final product, and otherwise, heat is directly applied
to the sheet to form the curved surface of the sheet by using
residual stress generated by the heat. However, such additional
processes increase the forming cost and period of the sheet.
DISCLOSURE
Technical Problem
[0007] Accordingly, the present invention has been made in view of
the above-mentioned problems occurring in the prior art, and it is
an object of the present invention to provide a dieless sheet
forming device that is simple in configuration to allow a forming
shape to be easily corrected even if a desired forming shape is
changed, while dimples or wrinkles are being not formed on the
formed sheet, thus being adequate for small quantity batch
production.
[0008] It is another object of the present invention to provide a
dieless sheet forming device that can form even the edge portions
of a sheet, without having the limitation on the thickness or size
of the sheet.
Technical Solution
[0009] To accomplish the above-mentioned objects, the present
invention proposed a dieless sheet forming device including: two
forming rollers rotatably disposed up and down to correspond with
each other and bent to various curvatures; and a plurality of
roller adjustment members whose one ends are fixed to each forming
roller in such a manner as to be adjusted in length to adjust the
curvatures of the forming rollers and the distances between the two
forming rollers, wherein the curvatures of the forming rollers and
the distances between the forming rollers through which a sheet to
be formed is passed are adjusted by means of the roller adjustment
members to change the forming shape of the sheet.
[0010] According to the present invention, that is, the sheet is
formed between the two forming rollers disposed up and down, which
makes the configuration of the device simple and allows the sheet
to be formed without having any limitation on the lengthwise size
thereof. Further, the curvatures of the forming rollers and the
distance between the forming rollers are adjusted by means of the
roller adjustment members, which make the forming shape easily
corrected, so that the device of the invention is adequate for
small quantity batch production.
[0011] In accordance with a preferred embodiment, each roller
adjustment member includes an external member having an internal
screw thread and an internal member having an external screw thread
and is adjusted in length in accordance with the screw-coupled
length between the external member and the internal member.
[0012] According to the present invention, like this, the
curvatures of the forming rollers are differently adjusted by means
of the length adjustment of the roller adjustment members, which
produces sheets having a single curvature, a double curvature, a
multi curvature, a twisted shape and the like.
[0013] In accordance with a preferred embodiment, the external
member is fixed to one of two forming rollers, and the internal
member is connected to the motor, so that the length of each roller
adjustment member can be adjusted through the rotation of the
motor. Each roller adjustment member may be connected to a separate
motor, and otherwise, the plurality of roller adjustment members
may be adjusted in lengths through the movement of a single motor
or a plurality of motors. Like this, the lengths of the roller
adjustment members can be easily adjusted through the motors.
[0014] In accordance with a preferred embodiment, the end of the
external member fixed to one of two forming rollers is rotatably
provided with a roller guide, which has a recess having a shape of
major arc (an arc bigger than a semicircle), into which the forming
roller is fittedly inserted. That is, while each forming roller is
being fittedly mounted into the rotatable recesses of the roller
guides thereof, the roller adjustment members are adjusted in
lengths to easily change the various curvatures of the forming
roller.
[0015] According to the present invention, the sheet to be formed
is inserted between the two forming rollers and pulled so as to be
passed through between the forming rollers, thus completing the
forming operation of the sheet. One of the forming rollers may be
connected and rotated at both ends thereof to roller rotation
motors, and otherwise, both of the forming rollers may be drove by
the roller rotation motors. In this case, the sheet engaged with
the forming rollers is pushed and formed through the rotation of
the roller rotation motors.
[0016] Each forming roller is made of steel having high modulus of
elasticity. Solid bar-type rollers can be treated through heat
treatment allowing an adequate elastic behavior during forming
procedure. Alternatively, each forming roller is wound by a
plurality of steel wires, and at this time, desirably, the steel
wire wound on the outer peripheral surface of each forming roller
becomes flat on an outside surface contacted with the sheet,
through grinding. Otherwise, the steel wire wound on the outer
peripheral surface of each forming roller has an oval section to
allow the outside surface contacted with the sheet to be flat. Like
this, the sheet is formed along the continuously curved surfaces of
the forming rollers having flat outer peripheral surfaces, thus
providing the sheet having a smooth formed surface on which no
local dimples or wrinkles exist.
Advantageous Effects
[0017] The dieless sheet forming device according to the present
invention can adjust the shapes of the upper and lower forming
rollers and the distance between them to form a sheet, and can be
accordingly simple in configuration and relatively small in
installation area, thus greatly reducing the die production cost,
the die storing cost and the die maintenance cost.
[0018] The curvatures of the forming rollers and the distances
between them can be adjusted by means of the roller adjustment
members, thus performing various changes in the forming shapes, so
that the device can be adequate for small quantity batch production
and can form a large-sized sheet, without having any limitation on
the length of the sheet, thus needing no additional mechanical
process.
[0019] The sheet can be formed along the continuous curved surfaces
of the forming rollers, without having any punches, so that even
the edges of the sheet can be formed and no dimples or wrinkles is
formed even on a thin sheet.
DESCRIPTION OF DRAWINGS
[0020] FIG. 1 is a schematic view showing one conventional die
sheet forming device.
[0021] FIG. 2 is a schematic view showing another conventional
multi-point sheet forming device.
[0022] FIG. 3 is a schematic view showing still another
conventional multi-point sheet forming device having elastic
pads.
[0023] FIG. 4 is a schematic perspective view showing a dieless
sheet forming device according to the present invention.
[0024] FIG. 5 is a perspective view showing a roller adjustment
member used in the dieless sheet forming device according to the
present invention.
[0025] FIG. 6 is a partial sectional view showing an example of the
roller adjustment member of FIG. 5 coupled to a motor.
[0026] FIG. 7 is a sectional view showing another example of the
roller adjustment member of FIG. 5 coupled to a motor.
[0027] FIG. 8 is a side view showing one example of a forming
roller used in the dieless sheet forming device according to the
present invention.
[0028] FIG. 9 is a side view showing another example of a forming
roller used in the dieless sheet forming device according to the
present invention.
[0029] FIG. 10 is a schematic perspective view showing one example
of the sheet forming between two forming rollers.
[0030] FIG. 11 is a schematic perspective view showing another
example of the sheet forming between two forming rollers.
[0031] FIG. 12 is a sectional view showing the arrangement of the
upper and lower forming rollers when a convex type sheet is formed
through the dieless sheet forming device according to the present
invention.
[0032] FIG. 13 is a perspective view showing the forming shape of
the sheet through the arrangement of the upper and lower forming
rollers of FIG. 12.
[0033] FIG. 14 is a sectional view showing the arrangement of the
upper and lower forming rollers when a saddle type sheet is formed
through the dieless sheet forming device according to the present
invention.
[0034] FIG. 15 is a perspective view showing the forming shape of
the sheet through the arrangement of the upper and lower forming
rollers of FIG. 14.
[0035] FIG. 16 is a sectional view showing the arrangement of the
upper and lower forming rollers when a twisted type sheet is formed
through the dieless sheet forming device according to the present
invention.
[0036] FIG. 17 is a perspective view showing the forming shape of
the sheet through the arrangement of the upper and lower forming
rollers of FIG. 16.
MODE FOR INVENTION
[0037] Hereinafter, an explanation on a dieless sheet forming
device according to a preferred embodiment of the present invention
will be in detail given with reference to the attached
drawings.
[0038] FIG. 4 is a schematic perspective view showing a dieless
sheet forming device according to the present invention. As shown,
a dieless sheet forming device 100 according to the present
invention has two forming rollers 101a and 101b horizontally
disposed up and down to correspond with each other. The forming
rollers 101a and 101b can be flexibly bent to various curvatures,
respectively.
[0039] Each of the forming rollers 101a and 101b is equipped with a
plurality of roller adjustment members 103 so as to adjust the
curvature. FIG. 5 shows an example of the roller adjustment member
103, and FIG. 6 is a partial sectional view showing the roller
adjustment member 103 in detail. The roller adjustment member 103
includes an external member 105 having an internal screw thread and
an internal member 107 having an external screw thread. The
internal member 107 is fittedly screw-coupled to the external
member 105, and the roller adjustment member 103 is adjusted in
length in accordance with the screw-coupled length between the
external member 105 and the internal member 107.
[0040] So as to easily adjust the length of the roller adjustment
member 103, as shown in FIG. 6, the roller adjustment member 103 is
connected to a motor. That is, the external member 105 is fixed to
the forming roller, and the internal member 107 is connected to the
motor, so that as the coupled depths of the internal member 107 to
the external member 105 are varied through the rotation of the
motor, the whole length of the roller adjustment member 103 can be
adjusted. A separate motor may be connected to each roller
adjustment member 103, but as shown in FIG. 7, the plurality of
roller adjustment members 103 may be adjusted in lengths through
the movement of a single motor or a plurality of motors.
[0041] The respective internal members 107 are rotated by means of
the single motor or the plurality of motors, thus adjusting the
lengths of the roller adjustment members 103, and accordingly, the
shape of the forming roller connected to one ends of the external
members 105 and the distance between the upper and lower forming
rollers 101a and 101b can be adjusted.
[0042] Returning to FIGS. 5 and 6, the roller adjustment member 103
has a roller guide 109 disposed rotatably at the end thereof fixed
to the forming roller 101a or 101b, that is, at the bottom end of
the external member 105. The roller guide 109 has a recess 109a
having a shape of major arc, into which the forming roller 101a or
101b is fittedly inserted. As the plurality of roller adjustment
members 103 is vertically arranged with respect to the horizontally
arranged two forming rollers 101a and 101b, the rotatable roller
guides 109 to which the forming rollers 101a and 101b are fitted
are adapted to allow the forming rollers 101a and 101b to be
naturally bent when the curvatures of the forming rollers 101a and
101b are adjusted through the length adjustment of the roller
adjustment members 103.
[0043] FIGS. 8 and 9 show examples of the forming roller. As shown,
the forming roller 101a is wound by a plurality of steel wires to a
plurality of layers. The steel wire wound on the outermost
peripheral surface of the forming roller 101a is desirably flat, on
an outside surface 111 contacted with a sheet, through grinding. As
the outside surface 111 of the forming roller 101a contacted with
the sheet is flat, occurrences of local dimples or wrinkling can be
prevented. Alternatively, the steel wire wound on the outermost
peripheral surface of the forming roller 101a has an oval section
to allow the outside surface 111 contacted with the sheet to be
flat. In the drawings, one forming roller 101a has been described,
but the other forming roller 101b has the same configuration as the
forming roller 101a.
[0044] Further, as shown in FIG. 4, the forming rollers 101a and
101b may be connected at both ends thereof to roller rotation
motors 113, thus being automatically rotated. In this case, as
shown in FIG. 10, the sheet 102 is fittedly disposed between the
forming rollers 101a and 101b and thus pushed and formed through
the rotation of the forming rollers 101a and 101b. At this time,
the forming shapes of the sheet 102 are determined upon the shapes
of the forming rollers 101a and 101b and the distance between them,
and as mentioned above, the shapes of the forming rollers 101a and
101b and the distance between them are adjusted by means of the
roller adjustment members 103 in accordance with desired forming
shapes of the sheet 102. Alternatively, the roller rotation motors
113 may be connected to any one of the forming rollers 101a and
101b, thus transmitting the driving force, and otherwise, no roller
rotation motors 113 may be provided. In case of the non-existence
of the roller rotation motors 113, as shown in FIG. 11, the sheet
102 is inserted between the forming rollers 101a and 101b and
pulled and formed from the opposite side to the inserted portion.
In the same manner as above, the forming shapes of the sheet 102
are determined upon the shapes of the forming rollers 101a and 101b
and the distance between them, and the shapes of the forming
rollers 101a and 101b and the distance between them are adjusted by
means of the roller adjustment members 103.
[0045] Like this, since the sheet 102 is formed through the
adjustment of the shapes of the forming rollers 101a and 101b and
the distance between them, the forming shapes of the sheet 102 can
be simply corrected in accordance with the changes of the desired
forming shapes of the sheet 102. Further, the forming rollers 101a
and 101b providing the continuous forming surfaces are rotated
while interposing the sheet 102 therebetween, thus forming the
sheet 102, so that no dimples or wrinkles exist.
[0046] Hereinafter, examples of forming the sheet through the
dieless sheet forming device according to the present invention
will be in detail explained.
[0047] In the dieless sheet forming device 100 according to the
present invention, the forming shapes of the sheet 102 are
determined upon the curvatures of the two forming rollers 101a and
101b corresponding up and down with each other and the distance
between them. That is, a length of the formed sheet 102 becomes
longer as the gap between the forming rollers 101a and 101b is
narrower, and contrarily, a length of the formed sheet 102 is
shorter as the gap between the forming rollers 101a and 101b is
wider. Under the above principle, the curved surface of the sheet
102 is formed.
[0048] For example, as shown in FIG. 12, if the gap between the
forming rollers 101a and 101b is narrow in the middle portion c of
the forming rollers 101a and 101 and wide in the edge portions a
and e thereof to provide a distance (a=e)>(b=d)>c, a length
of the formed sheet 102 becomes long in the middle portion c' of
the formed sheet 102 and short in the edge portions a' and e'
thereof, as shown in FIG. 13, thus providing a length
c'>(b'=d')>(a'=e') and accordingly forming the convex type
sheet 102.
[0049] Further, as shown in FIG. 14, if the gap between the forming
rollers 101a and 101b is wide in the middle portion c of the
forming rollers 101a and 101 and narrow in the edge portions a and
e thereof to provide a distance c>(b=d)>(a=e), a length of
the formed sheet 102 becomes short in the middle portion c' of the
formed sheet 102 and long in the edge portions a' and e' thereof,
as shown in FIG. 15, thus providing a length
(a'=e')>(b'=d')>c' and accordingly forming the saddle type
sheet 102.
[0050] Furthermore, as shown in FIG. 16, if the gap between the
forming rollers 101a and 101b is gradually wider in one direction
thereof to provide a distance e>d>c>b>a, a length of
the formed sheet 102 becomes gradually longer in the order of
a'>b'>c'>d'>e', thus forming the twisted type sheet
102.
[0051] The curvatures and distances of the forming rollers 101a and
101 are adjusted to various sheets by means of the length
adjustment of the roller adjustment members 103, and accordingly,
the sheet 102 can be formed to various shapes. Therefore, the sheet
forming device according to the present invention can be applied
for small quantity batch production, can form even the edge
portions of the sheet, and can form the sheet without having the
limitation on the length of the sheet.
[0052] While the present invention has been described with
reference to the particular illustrative embodiments, it is not to
be restricted by the embodiments but only by the appended claims.
It is to be appreciated that those skilled in the art can change or
modify the embodiments without departing from the scope and spirit
of the present invention.
* * * * *