Note: Descriptions are shown in the official language in which they were submitted.
CA 02240249 1998-06-10
TECHNICAL FIELD
The invention relates to roll forming machinery, forming, a continuous strip
of
sheet material, and in particular, to such roll forming machinery in which the
spacing
between the roller dies can be adjusted along a diagonal axis, by a single
adjuster,
in response to variations in the thickness of the web. Adjustment is also
provided for
webs of varying width, and for correcting warping of the workpiece.
BACKGROUND ART
Roll forming machinery usually has a plurality of sets of roller dies, usually
arranged in upper and lower die pairs, and usually spaced apart along the
length of
the machine on roller stands. Typically, the roller dies at one stand will
produce a
continuous formation in the web, and the roller dies of the next stand will
produce
another formation, or for example increase the angle of the formation which
has
already been started at the previous stand and so on.
A wide variety of commercial and other products are made on such roll forming
machines, such as roof decking, siding, and a large number of components for
consumer equipment. The shapes may simply be webs with edge formations formed
along one edge or both, or may be C sections or U sections but in many cases
consist
of relatively complex formations with longitudinal formations being formed
along the
length of the web, side by side.
= Generally speaking at each stand of roller dies there are two lower dies and
two
upper dies arranged in pairs, to engage and form the web on either side of a
central
1
CA 02240249 1998-06-10
web axis. The lower dies engage the underside of the web and the upper dies
engage
the upper side of the web. The dies have circular shapes, and are mounted on
rotatable axles so that the dies can rotate at the same speed as the sheet
metal.
A gear drive mechanism is coupled to the dies so as to drive them at the speed
of the sheet metal.
Each set of such roller dies must be designed to provide a particular
formation
in the web. In addition, each pair of dies must have a clearance between them
determined by the thickness of the web.
Where the web is formed by bending, the upper and lower dies have two
forming planes, usually a horizontal plane and an angled plane. Some dies
simply
form curved shapes, but these can be regarded as defining at least two planes.
Where it is desired to discontinue working on a web of one thickness, and to
then run a web of another thickness through the dies, each pair of roller dies
must be
readjusted to a new clearance, to accommodate the new thickness of the new
web.
This involves costly down time, in order to make the fine adjustments.
All of this is very well known in the art and is accepted as the normal
operating
procedure.
It is however well known that a further problem exists in roll forming. The
web
of sheet material which provides the basic feed stock for the roller die
apparatus
should preferably maintain its thickness within very narrow limits, along the
entire
length of the web. If there is any significant variation in thickness in the
web, then the
pairs of dies, being fixed as to clearance, will produce varying effects on
the web as
2
CA 02240249 1998-06-10
the web passes along the roller stands, or the web may jam causing stoppage of
the
line.
In practice, it is well known that some web material varies in thickness to a
greater extent than is permissible. This results in unusual effects being
produced in
the final formed web, which may warp or bend or twist, or even jam.
Generally speaking, it is not possible to adjust the clearances of the roller
dies,
during the actual operation of the machine, and the best that can be done is
that in
the initial set up, the machinist will set the die clearances of each pair of
dies to a
predetermined average web thickness. The results obtained in this way however
are
not always entirely satisfactory.
It would in theory be desirable to provide for automatic self-adjustment of
the
spacings or clearances between the pairs of dies in each stand. However, due
to the
shaping of the dies there are difficulties in such adjustments. Usually the
dies will have
two surfaces, one of the surfaces being more or less horizontal, or at least
parallel to
the plane of the web itself, and the other of the surfaces being at a web
forming angle.
Adjustment of the clearances between pairs of roller dies of this type
requires
adjustment in two planes.
Preferably these adjustments should be capable of being made while the web is
running through the dies, so as to accomodate variations in web thickness
without
stopping the web.
3
CA 02240249 1998-06-10
Preferably these adjustments in both planes should be capable of being made
by a single adjustment control, so that the operation of the one control,
makes the
adjustments along an axis which is diagonal to the roll axes of the dies.
Another set of problems arises if it is desired to use the same roller dies,
to
form a web having a width which is greater, or narrower than a preceding web.
It is therefore desirable to provide for roller die stands arranged in pairs,
in
which one of each of the stands in each of the pairs shall be transversely
moveable
relative to the other.
Given both die clearance adjustment, and stand width adjustment, it would be
possible, using one set of roller die stands and dies, to provide for the
processing of
webs both of different thicknesses, and also webs of different widths, with a
minimum
of machine down time for the changeover from one to the other. This would
enable
a manufacturer to produce a standard rolled form section such as a "C" section
in a
variety of widths and in a variety of gauges, from a single machine. This
would reduce
the capital investment in machinery. In addition it would reduce the down time
required for change over from one web to another and also reduce the need for
skilled labour.
In addition where the width of the web was considerable, it was the practice
to insert
web support rolls, or spacer rolls were simply mounted on the lower die axles
between
the lower dies. These support rolls simply functioned to support the central
region of
the web to prevent it from sagging,bending or warping, and keep it level.
4
CA 02240249 1998-06-10
Additional savings would be achieved if the need for spacer rolls could be
avoided, and instead some other form of support could be provided between the
adjacent die stands, to support the web. Preferably this alternative form of
support
should be capable of being introduced from beneath, between the adjacent die
stands
by some form of powered mechanism, when it was required for a wider web, and
removed to accomodate a narrower web,when it was not required, and without the
need for mounting on the lower die axles themselves.
A further problem arises with roll forming certain sections, particularly
sections
which have the shape of a letter C with inturned flanges, or a partially
closed-in box
section.
In this type of section, the two edges or flanges of the C, or partially
closed-in
box, are turned inwardly. This was usually done by roll forming the edge
flanges first,
and then roll forming the C bends later, i.e. downstream. Special dies are
required
to form the last bends, and it is desirable to provide for adjustment of these
dies.
Adjustment of such dies in this location however, to accommodate variations in
web
thickness and to form different sizes of C-section presents further problems.
BRIEF SUMMARY OF THE INVENTION
One aspect of the invention provides for transverse width adjustment of the
die
stands, and means for inserting or removing a web support mechanism between
the
adjacent die stands.
This form of the invention includes a movable web support movable upwardly
and downwardly between the die stands, with the support being provided with a
5
CA 02240249 1998-06-10
plurality of smaller free running rolls which can be introduced between each
pair of
adjacent die stands, thus supporting the web where it extends from one set of
dies to
the next, instead of being supported by spacer rolls located directly between
the pairs
of lower dies, as was done in the past.
Another aspect of the invention provides a roller die apparatus for supporting
pairs of roller dies in predetermined clearances, and having means for moving
one of
said roller dies to adjust the die clearance between the pair of dies in a
plane which
is diagonal to the roller die axis. In other cases where the web, or a portion
of it is
substantially horizontal there may be a need only for one form of adjustment,
in the
vertical plane.
Preferably one of the dies is fixed, and the other of the dies incorporates
diagonal adjustment movement so as to keep all of the adjustment movement in a
common location where it is readily accessible for servicing and adjustment.
The invention provides a single control movement transmission coupling all of
the moveable dies together for diagonal movement in unison, and power operated
means for operating the movement transmission.
The invention provides a thickness sensor for sensing the thickness of said
web material workpiece, and generating a thickness signal and signal
responsive
means for generating movement signals for moving said movement transmission
means, whereby to procure simultaneous movement of said moveable dies.
6
CA 02240249 1998-06-10
The invention also provides for an edge forming roller die assembly for
rolling
the edge formations and means for moving said at least some of said edge
forming
roller dies relative to one another, to vary the clearance between them.
A further aspect of the invention provides for a straightening assembly,
comprising straightening rolls adapted to engage the workpiece after exiting
from the
roller dies to prevent or correct warping.
A further aspect of the invention provides for positive rotary driven pinch
rolls
and side guide rolls enaging the web upstream where it enters the machine and
keeping the web axis truly centered with respect to the forming dies.
the invention also relates to a method of roll forming a web workpiece.
The various features of novelty which characterize the invention are pointed
out
with more particularity in the claims annexed to and forming a part of this
disclosure.
For a better understanding of the invention, its operating advantages and
specific
objects attained by its use, reference should be had to the accompanying
drawings
and descriptive matter in which there are illustrated and described preferred
embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a side elevation of a roller die apparatus for working a web of
sheet
material partially cut away, and illustrating a plurality of roller die stands
at spaced
apart intervals along the path of the sheet material and controls shown
schematically
with respectve groups of dies indicated as Group 1, 2, 3, 4 and 5;
Figure 2 is a top plan of part of Figure 1 in cross section;
7
CA 02240249 1998-06-10
Figure 3 is a a sectional side elevation, along lines 3-3 of Fig 1 of the
roller
apparatus of Figure 1;
Figure 4 is a front end view of the the roller stands, and the transverse
movement mechanism;
Figure 5 is a cross section of initial upstream pinch rolls forming Group 1 of
the
roller die apparatus of Figure 1 at the line 5-5;
Figure 6 is a cut away perspective of a portion of the pinch rolls of Fig 5;
Figure 7 is a cross section of a portion of the pinch roll mechanism of Figure
5;
Figure 8 is a cross section of one roller stand of Groups 2 or 3, sectioned
along
the line 8-8 of Figure 2, and showing details of the upper die movement means;
Figure 9 is a section corresponding to a portion of Figure 8 along line 9-9 of
Figure 8;
Figure 10 is a cut away perspective of the adjustment mechanism of Figure 7
and showing movement of the upper die;
Figure 11 is a cut away perspective showing further details of the adjustment
. mechanism of Figure 10, showing further movement of the upper die to procure
movement ona diagonal axis;
Figure 12 is a top plan view partially cut away showing the diagonal corner
forming upper dies of Group 4;
Figure 13 is a section along line 13-13 of Fig 12, of the upper diagonal
corner
forming dies;
8
CA 02240249 1998-06-10
Figure 14 is a side elevational view of the diagonal corner forming dies and
the
warp correcting mechanism and dies;
Figure 15 is an end view of the warp correcting mechanism of the invention of
Group 5, showing both sides of the machine;
Figure 16 is a side elevation of the warp correcting mechanism of Group 5;
Figure 17 is an end view of one side of the same mechanism as Fig 15
showing the warp correcting mechanism forming a C section member;
Figure 18 is an end view of the warp correcting mechanism of the invention,
forming a U section member;
Figure 19 is a cut away persective view of a portion of the warp correcting
mechanism, in one position;
Figure 20 is a cut away perspective corresponding to Fig 19 showing the parts
in another position;
Figure 21 is a side elevation of a portion of the drive mechanism for the
stands
of Groups 4 and 5;
Figure 22 is a schematic view showing the progressive bends involved in
making a U section member;
Figure 23 is a schematic view similar to Fig 22, showing the progressive bends
involved in making a C section member, and ,
Figure 24 is an enlarged cut away perspective of the sliding mechanism
connecting the control bars together for movment in unison.
9
CA 02240249 1998-06-10
DESCRIPTION OF A SPECIFIC EMBODIMENT
Referring first of all to Figure 1, it will be seen that this illustrates a
roll forming
apparatus of type used in conjunction with web sheet metal processing lines.
Additional equipment may comprise an uncoiler, a flattener, a cut off die or
shear, and
a stacker or conveyor, all of which components are essentially well known in
the art,
and these are not shown for the sake of clarity.
The roll forming apparatus which is shown here for the purpouses of
illustrating
the invention,comprises a base indicated generally as B, defining an upstream
end
U, and a downstream end D, and the web sheet metal passes from left to right,
in
Figs 1,2,and 3 from the upstream end U, to the downstream end D, continuously,
while being progressively roll formed. Generally the apparatus described may
be used
for the formation of two different sections, namely a U-section Su (Fig 22),
and a C-
section Sc (Fig 23). These Figures illustrate the sequence of progressive
bends which
are formed as the web passes from one die station to the next.
These two sections are commonly used in construction, and may be required
to be formed from webs of greater or lesser thickness, depending upon their
application, and may be required to be formed with greater or lesser widths
and flange
dimensions. The apparatus to described enables a wide range of sizes of these
= various sections to be formed on a single machine, using one single set of
dies.
Clearly the apparatus can also be used to form webs of other shapes, but in
that case
some changes in the dies will normally be made to permit this.
CA 02240249 2006-07-17
Roll forming of the web is performed progressivley at a series of roller die
stands indicated generally as 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
22, 23, 24,
25, 26, and 27. The stands are mounted on the base B, in a manner to be
described
at spaced apart intervals, along the path of the web W. The roller die stands
are
mounted in five groups. Group I is the lead in or pinch roll section where the
flat web
is gripped and driven along the path of the rest of the rolls. Groups 2 and 3
are
forming dies, which function to form the progressive bends in the web. Groups
4 and
5 perfom finishing and straightening actions.
Stands 10 forms Group 1.
Stands ,11,12,13,14, and,15 form Group 2.
Stands 16, 18, 19, 20, 21,and 22 form Group 3.
Stands 23,25,26, and 27 form Groups 4 and 5.
Each pair of stands is designated as 10 and 11 etc. Stands 23, 24,25,
26 and 27 form Groups 4 and 5 where finishing functions are performed , to be
described below.
The stands 10 forming Group I and stands 11 to 15 forming Group 2 are
mounted on respective continuous side plates 38 and 40., (Figures 1 and 3) the
tower
edges of which are slidably mounted on base B on a transverse upstrearn guide
rail
42 and downstream guide rail (not shown), and guide shoes 46. Transverse power
drive means 52 operates to move the plates 38 and 40 together or apart.
In this way the plates 38 and 40 can be slid towards and away from one
another, to
accomodate webs of varying widths.
11
CA 02240249 2006-07-17
Groups 3,4,and 5 of the stands are mounted on side plates 48 and 50 which
are separate from side plates 38 and 40 and can be moved towards and away from
one another as described below. Plates 48 and 50 can be slid towards and away
from
one another independently of plates 38 and 40, on respective guide rails and
guide
shoes (not shown) similar to guide rail 42 and shoes 46. Transverse power
drive
means 52 drive plates 48 and 50 towards or away from oneanother.
. Groups 1 and 2 of the die stands can thus be moved towards and away from one
another, independently of the movement of Groups 3, 4 and 5.
The invention will now be described with reference to these separate groups
of die stands.
GROUP I
The stands 10, of Group 1(Figures 4, 5, 6,and 7) consist of upper and
lower transverse drive shafts 60 and 62. Upper and lower dies 64 and 66 are
mounted on their respective shafts , and the shafts are mounted in slideable
upper
and lower bearing sleeves 68, 70. The sleeves are slideably supported in
plates 38
and 40 and support the shafts for upper and lower dies 64 and 66. Shafts 60
and 62
slide telescopically in the sleeves 68 and 70 , in plate 40 (not shown) and
are
fastened in sleeves 68 and 70 in plate 38 (Fig 5). Suitable drive gears
(described
below) drive shafts 60 and 62 in their sleeves,so that the upper and lower
dies in
stands 10 are driven in unison.The first dies 64,66 form pinch rolls and are
of cylindrical shape in profile, so as to simply grip the upper and lower
surfaces of the
sides of the web where it enters the machine and ensure a positive feed of the
web
12
CA 02240249 2006-07-17
towards the downstream dies. In order to assist in this function edge guide
rolls 71
are mounted on blocks 72androtate on vertical axes. The edge guide rolls
contact the
side surfaces of the upper dies 64, and are driven by frictional contact with
dies 64.
In this way a positive edge guide function on the side edges of the web is
achieved
by the guide rolls 71 which are frictionally driven at the same speed as the
pinch rolls
themselves.
Upper and lower bearing sleeves 68 and 70 are mounted in shaft
openings which permit transverse sliding of the sleeves and shafts for reasons
to be
described below.
The upper and lower sleeves 68 and 70 are coupled to blocks 72 which are
connected to respective jack screws 73 by rods 74 and can be slid inwardly and
outwardly relative to their plates 38 and 40, by means of jack screws 73.
Blocks 72 are further provided with lower guide wedges 75 and upper guide
wedges
76 which ride below and above the edges of the web as it passes through the
pinch
rolls.
Pinch rolls can thus be moved inwardly together, by moving plates 38 and 40
together, and can also be moved inwardly and outwardly independent of plates
38 and
40 by jack screws 73 and blocks 72.
This is of importance when changing over from fabricating a U secfion to
fabricating
a C section, or vice versa, for reasons which will be described below.
13
CA 02240249 2006-07-17
Group 2
The die stands in Group 2, namely, stands 11,12,13,14,and,15 are different
from
stands 10 but are of an identical design to one another, except for the
shaping
of the dies themselves which will vary progressivley from one stand to the
next in
known manner.
In stands 11 to 15, lower die drive shafts 80 are supported by suitable
bearings
directly in side plate 38 . These drive shafts are driven by a suitable gear
train
described below, and support lower forming dies 82. Telescoping driven shafts
84
extend from drive shafts 80 to driven hubs (not shown) rotatably mounted in
side
plates 40, and driven shafts 84 extend completely through these driven hubs .
Lower
forming dies 82 are supported on such driven hubs (Fig. 8). In this way the
lower
forming dies of all of stands 11 to 15 are driven in unison.
Upper dies 86 in each of stands 11 to 15, are carried on upper shafts 88.
Eccentric bearing sleeves 90 which carry upper shafts 88 are both slidably and
rotatabty mounted in plate 38. Sleeves 90 define shaft openings 92 which are
offset
(Fig 8) from the central axis of the sleeves 90 and from the axis of shafts
88, for
reasons described below. Upper die shafts 88 are driven by a gear train
connected
to the lower shafts to be described below.
Telescopic driven upper shafts 94 are received in die shafts 88 and extend
through
die hubs (not shown) mounted in plate 40 for carrying upper dies 86 (Fig. 8).
These
hubs are mounted in eccentric sleeves (not shown), mounted in plate 40, which
are
similar to sleeves 90 mounted in plate 38. Upper dies 86 are carried on shafts
14
CA 02240249 2006-07-17
88: and upper dies 86 (Fig. 8) are supported on these hubs, and dies 86
are thus driven in unison.
In accordance with the present invention, as explained above, there is
provided means for adjusting at least one of the upper and the lower dies
relative to
the other, so as to adjust the vertical clearance between the dies, to match
the
thickness or gauge of the web material as closely as possible. Such
adjustments in
accordance with the invention can be made while the web is actually running
through
the dies, thus compensating for variations in the thickness of the web along
its length,
all of which wilt be described below.
In this embodiment of the invention, it will be seen that it is the upper dies
that are all
adjustable relative to the lower dies which are on fixed axes. However it will
be
appreciated that the lower dies could be made adjustable and the upper dies
remain
fixed if that was thought to be desirable.
As explained above each of the upper shaft sleeves 90 have eccentric shaft
openings 92 for receiving die shafts 88 and the driven hubs (not shown). Each
sleeve 90 is supported in a respective opening in respective plates 38 and 40.
Sleeves 90 are able to rotate in their plates 38 and 40,in a manner to be
described below, and thus cause upward and downward semi arcuate movement of
upper die shafts 88 and their dies 86.
The sleeves 90 are also adustable axially, ie inwardly and outwardly, this
produces
what is in the end an adjustment along the upper dies of a diagonal axis
relative to the
web to accomodate minor variations in the web thickness as it passes both
through
CA 02240249 1998-06-10
the horizontally opposed faces of each die pair, as well as through the
angularly
opposed faces of the die pair.
The mechanism by which this adjustment is achieved is best seen in Figures
8, 9, 10, and 11. Referring to Fig 9 each sleeve 90 is connected to a semi
arcuate
control body 100. Two bolts 102 pass through arcuate slots 104 in body 100 and
are
bolted into the sleeve 90. Control body 100 is formed with a pair of upwardly
directed
guides 106 which define a U shaped slot. An adjustment pin 108 is received in
the U
shaped slot of guides 106. Pin 108 extends sideways from an adjustment bar 110
which extends along the top of plate 38. The identical structure is provided
for the
opposite sleeve (not shown) which is mounted in plate 40. An identical bar
110B
extends along the top of plate 40.
Pins 108 are located at spaced intervals along bar 110 at spacings
corresponding to
the locations of sleeves 90. Adjustment bar 110 is guided at intervals along
plate 38
by rails 112 located in channels 114 formed in the top of plate 38. Slide
shoes 115
engage rails 112 and bolts 116 secure shoes 115 to bar 110.
A suitable power mechanism 118 at one end of bar 110 pushes or pulls it to
provide
the adjusting movement. As the bar moves it will force pin 108 located between
guides 106 to rotate body 100 through a small angular extent, an arc of one or
two
degrees in most cases being sufficient. This will in turn force the rotation
of sleeve 90
through the same arc. Since the sleeve 90 carries the die shaft 88 off centre
in an
eccentric manner shaft 88 will swing upwardly or downwardly a fractional
amount,
which will be sufficient to adjust for the variations in thickness of the web.
16
CA 02240249 2006-07-17
This explains the adjustment transverse to the shaft axis.
Adjustment along the shaft axis is also provided. This is produced by the
block 120
secured to plate 38 and the cooperating roller 122 bolted to body 100.
Block 120 is formed with a generally diagonal slot 124 (Fig 11), which
receives roller
122. When body 100 is moved by pin 108 so as to produce the small angular
adjustment, it also causes roller 122 to move along slot 124. The axis of slot
124 is
angled along a diagonal axis so that roller122 must move along that angled
axis.
This will cause body 100 to move towards or away from plate 38. Sleeve 90 to
which
body 100 is attached will thus be forced to slide into or out of plate 38.
Again the
actual degree of movement is slight, but it is sufficient to produce the
adjustment in
die clearance required to accomodate variations in the web thickness.
Movement of the body 100 caused by roller 122 and slot 104 will cause guides
106
to slide outwardly or inwardly relative to pin 108 but again the degreee of
movemnt
will be slight. It will thus be seen that by this mechanism movement of the
single
control bar 110 will cause simuttaneous movement of sleeve 90 both transverse
to its
axis and also axially along its axis. These two degrees of movement will
translate into
a movement of the upper die 86 along a diagonal axis relative to the lower die
82.
The bolts 102 can be loosened, and the body 100 can be adjusted by sliding the
slots
104 relative to the bolts which can then be tightened once more. This enables
the
machine to be set up prior to operation to the optimum die clearance for a
particular
thickness of web.
17
CA 02240249 2006-07-17
GROUP 3
The third group of die stands consists, in this embodiment of stands 16 to 22.
It wiil
of course be appreciated that the number of stands in each group will depend
on the
purposes for which the machine is designed, and the numbers shown here are
purely by way of example, and without limitation.
As mentioned above stands 16 to 22 are supported on side support plates 48 and
50
which are separate from plates 38 and 40 and can thus be adjusted separately
as
required. Plates 48 and 50 are slideably mounted on transverse rails (not
shown)
which are supported on base B. By suitable power operated means, described
below,
the side plates 48 and 50 can be slid towards or away from one another, so as
to
accomodate webs of various different widths, or to form sections having
various
different dimensions. For example when forming a U section member onty two
bends
are required in the web. Stands 11 to 15, on plates 38, 40, can thus be moved
apart
so that their dies do not contact the web. The forming of the U section would
thus
start at stand 16.
On the other hand, when forming a C section four bends must be fonned. In this
case
stands 11 to 15 will form the two outer bends in the web. Stands 16 to 22 will
form the
two inner bends. Compare the U section bends in Figure 22 with the C section
bends
shown in Figure 23.
Each of stands 16 and 17 etc are of identical construction to one
another, apart from the actual dies carried by the stands, which will have
profiles
18
CA 02240249 2006-07-17
which vary progressively in known manner so as to form the web in a
progressive
continuous fashion, as is well known in the art.
Thus each of stands 16 etc, have lower die drive shafts, carrying lower dies.
Shafts 110 are mounted directly in plates 48, in suitable bearings, and are
driven by a suitable gear drive to be described below. In plate 50 lower die
hubs (not
shown) are mounted directly in plate 50, in suitable bearings, and carry lower
dies.
Driven shafts slide telescopically into shafts, and extend completely
through the hubs in plate 50, for reasons to be described. tn this way lower
dies
(Fig 2) are driven in unison.
Upper die drive shafts are mounted in eccentric sleeves. Sleeves
have openings to receive shafts which are offset from the central axes of
sleeves
for reasons to be described. Sleeves are both rotatable in plate 48, and
are also capable of axial sliding relative to plate 48, for the purpose of
adjusting die
clearances as will be described below. In plate 50 the die hubs (not shown)
are
rotatably mounted in sleeves (Fig 2) similar to sleeves in plate 48. Shafts
and their hubs carry upper dies. Sleeves have hub openings
(not shown) which are offset relative to the central axes of their hubs in the
same way
as in sleeves. Sleeves are rotatable in plate 50, and are also slideable
axially relative to plate 50, for the purposes of adjusting the die clearances
in a
manner to be described below.
19
CA 02240249 2006-07-17
Die drive shafts and hubs 160 are connected by driven shafts which are
telescopically received in drive shafts and which extend completely through
hubs
160 for reasons to be described.
It will understood that the Group 3 die stands 16 to 22 can be brought towards
one
another or away from one another by sliding movement of plates 48 and 50. This
movement is independent of similar movement of die stands 10 to 15 which is
achieved by moving plates 38 and 40 towards and away from one another.
However all of the upper dies in stands 16 to 22 are adjustable relative to
their lower
dies, in the same way as the upper dies in stands 11 to 15 described above, so
as to
allow for variations in web thickness during passage of the web through the
dies.
This means that by adjusting plates 38 and 40 and plates 48 and 50 towards
or away from one another, various different web formations can be made on the
one
machine with one set of dies, on webs of varying width. For example a U-
section can
be made by simply spreading plates 38 and 40 apart, and allowing the web to
pass
directly to die stands 16 to 22. Suitable adjustments will be made in the
positioning
of pinch rolls so as to ensure that they grip the edges of the web for
positive guidance.
Where it desired to form a C-section, then plates 38 and 40 are positioned a
first
distance apart so that their dies form the edge flange bends of the C-section_
Plates
48 and 50 will be brought closer together than plates 38 and 40 so that their
dies are
located inside the edge flanges and form the bends at inside of the C-section.
CA 02240249 2006-07-17
Plates 48 and 50 may be moved by any suitable transverse power movement
mechanism indicated generally as 164.
In addition all of the upper dies at stands 16 to 22 have clearance adjustment
mechanisms similar to those described for stands 11 to 15, and shown in
Figures 8,9,10,and 11. Accordingly these further adjustment mechanisms will
not be
described again since they are fully described above.
There is however one significant difference to be noted.
Since plates 38,40 move towards or away from one another independenity of
plates
48, 50, and vice versa, it is necessary to provide for second control bars 170
on
each side of the apparatus, for plates 48 and 50, which control bars are
identical to
bars110 described above.
Control bars 170 extend along to tops of plates 48,50 and are guided by guides
and
shoes (not shown) in the same fashion as bars 110 (Fig 8).
Control bars 170 have identical pins 108 extending therefrom which perform the
same purpouse of moving the adjustment mechanisms of the upper dies , as has
been described above.
However it is desireable that both bars 110 and bars 170 shall be moved
simu{taneously by the same power adjustment mechanism118 described above. T
his
will ensure that the same die clearance adjustment movement is made for all
dies
stands 11 to 22 simultaneously. In order to achieve this bars 110 and 170 are
tinked
together by slideable links 172. The links enable one of bars 110 and 170 to
21
CA 02240249 1998-06-10
move transversely relative to the other, by providing a transverse sliding
connection
between them (Fig 24).
In order to provide support for the web where it extends between the die
stands, a
web support table 180 (Fig 3) is provided which extends the entire length of
the
machine. Table 180 is vertically moveably mounted on power columns 182 by
means
of which it can be raised and lowered. Table 180 is formed with two upstanding
plate
portions 184-184, which are spaced apart from one another, but which are
sufficienlty
close that they can be moved up and positioned between right and left hand
sets of
dies.
The upper edges of plate portions 184, are formed with semi circular recesses
186
which are located so as to fit around the dies shafts and hubs without
interfering.
Between the recesses 186 there are located a plurality of small web carrying
rollers
188, which are free running. By raising the table to the appropriate height
the rollers
188 can be brought into contact with the underside of the web where it extends
between adjacent die stands, and will provide support for the web to prevent
it from
sagging or bending between the die stands.
GROUP 4
The fourth group of die stands comprise the stands 23,24,25,and 26. The dies
in this
group function to force the corners of the web section into a rigid angle,
usually
although not invariably a right angle . It will be appreciated that where the
section is
a simple U-section (Fig 22) this function may not be difficult to achieve.
However
where the section is a C-section (Fig 23), then the final precision working of
the inside
22
CA 02240249 2006-07-17
corners, becomes more difficult. Figure 12 illustrates four stands of corner
fonming
rolls (described below) but without illustrating the web.
Figure 13 illustrates one of the comer forming rolls in section with a C
section web
shown in the process of being worked.
Each of stands 23 to 26 has a lower shaft 200 (Fig 13 and 14) which is mounted
in
suitable bearings directly in respective plates 48,50 . Suitable drive gears
to be
described below drive all of lower shafts 200. In stands 23 and 25' .,on plate
48,there are lower dies 202 mounted on shafts 200, but no corresponding upper
dies, on that side of the machine . On stands 24 and 26 , on plate 50,there
are
lower dies 202 mounted hubs 206, but no upper dies, on that side of the
machine.
Driven shafts 208 extend telescopically from shafts 200 and pass through hubs
206,
so that the lower dies are driven in unison.
In stands 23 ,24 , 25 and 26 , there are hubs 210 carrying lower dies 212.
Driven shafts 208 extend telescopically from shafts 200 across the machine
through
hubs 210 and thus the lower dies on both sides of each stand are driven in
unison.
In stands 23 ,24 , 25 and 26 there are upper die sleeves 216 (Fig 13)
rotatably
and slideably mounted in respective plates 48 and 50: Wthin the sleeves there
are
secured drive housings 218, located on axes which are ec.centric-to the
centres of
sleeves 216. 1lVsthin housings 218 there are rotatable stub shafts 220 mounted
in
suitable bearings. On the inboard ends of shafts 220 there are crown gears
222.
Angled die shafts 224 are carried in the inboard ends of housings 218. Gears
226 on
shafts 224 mesh with gears 222. Angled comer forming upper dies 228 are
mounted
23
CA 02240249 2006-07-17
on shafts 224 and are oriented so that they can reach around the already
formed
edge flanges of a C section workpiece, and fit into the fower corner of the C
section
and firmly force it into the desired comer configuration.
Lower dies 212 are formed with an annular lip 230 (Fig 13) to act as an
abuttment
against which the upper angled die can press the corner of the workpiece
(Fig13) and form the comer more securely. For additional hold free running
edge rolls
232 are mounted on blocks 234. Rolls 232 engage the outer side surface of the
C
section or U section to ensure that the comer is formed correctly in the
workpiece.
The upper angled comer dies 228 are thus adjustable upwardly and downwardly by
rotation of sleeves 216, in the same manner as are the upper dies on the die
stands
11 to 22 described above. Control rod bars 170 (Fig 12 ) are is connected to
sleeves 216 by mechanism similar to that already described for stands 11 to
22. The
same mechanism also produces axial movement of sleeves in plates 48 and 50 in
the
same way. -
Group 5
Die stands 27 form group 5 and function to correct any tendency for the
workpiece to
warp as it leaves the dies.
For this purpose lower rolls 250 are secured on shafts 252(Figs 14 15 16 and
17).
Rolls 250 are located so as to engage to underside of the workpiece and hold
it
secure. Lower shafts 252 are driven by gear means described below.
Upper correcting rolls 254 are moveably mounted on shafts 256 carried in
sleeves
258. Note that upper rolls 254 are offset relative to lower rolls 250.
24
CA 02240249 1998-06-10
Sleeves 258 may be moved up and down by rods 260 (Figs 19 and 20) and power
means 262. This will cause upper rolls 254 to deflect or to release the edges
of the
web, and control warping.
For additional guidance side rolls 264 are mounted on blocks 266 (Fig 19 and
20)
and rotate in contact with lower rolls 250 to correct sideways deflection of
the web.
DRIVE MECHANSIM
The drive for the dies on stands 10 to 22 consists of relatively conventional
gear
drives 300 intermeshing with one another and driven by motor 302.
The drive for the dies of stands 23 to 27 is more complex, and is shown in
more detail
in Figure 21. The drive for the lower dies 202 and 212 is still relatively
straightforward
since all of the drive gears 304 are located on the outside of plate 48, in
this
embodiment. However the drive gears 306 for the upper dies 228A and B are
located on the respective plates 48 and 50 , since there are no cross shafts
connecting the upper dies on one side with the upper dies on the other side of
the
machine. Gears 306 are driven by chain systems or the like (not shown), so
that the
dies rotate in unison.
The drives for the warp correcting rolls of stand 27 are also located on both
sides of
the machine since there are no cross shafts on this stand. Lower shafts 252
are
driven by gears 308 and chains 310. The upper dies which can be adjusted
upwardly
and downwardly to accomnomdate the U section, or the C section, are driven by
gears 312 connected through idler gears 314 to gears 316. Idler gears 314 are
CA 02240249 1998-06-10
mounted on two swingable arms 318 so as to permit upward and downward
movement of gears 312.
It will be appreciated that this explanation is not detailed in every respect
since such
drive systems are known in the art and various different drives could be
adapted to
perform the functions required.
WEB SENSING
Referring to Figure 1 it will be seen that a web thickness sensing unit 330 is
provided at the upstream end U of the roll forming apparatus. The thickness
sensing
unit may typically comprise a pair of rolls, and a signal generator (not
shown)
connected to a computer control centre (not shown).
The sensing unit 330 operates to sense the thickness of the web and to cause
the computer control to send adjustment signals for adjusting the die
clearances in the
manner described above.
In addition to providing for sensing the thickness of the web provision is
made
through means such as optical sensors (not shown) to sense any warping of the
section and to send signals to the computer control. This will in turn send
signals for
adjusting upper rolls 254 and side rolls 264 so as to correct any tendency of
the
section to warp.
The method of roll forming is self evident from the foregoing.
The foregoing is a description of a preferred embodiment of the invention
which
is given here by way of example. The invention is not to be taken as limited
to any of
26
CA 02240249 1998-06-10
the specific features as described, but comprehends all such variations
thereof as
come within the scope of the appended claims.
27
