Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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A SHEAR W~EEL FOR CUTTING FABRIC
BACKGROUND OF THE INVENTION
This invention relates to a shear wheel for
cutting fabrics e.g. tire cord fabric.
Discussion of the Prior Art:
In general, prior art rotary shear wheels have
either 90 angle cutting edges or relief angle cutting
edges (less than 90~). One of the problems associated
with the 90 angle cutting edges is that the wear is
faster than a relief angle cutting edges. Another problem
is that the 90 angle cutting edges may mar the fabric
materlal during cutting by the opposite unused cutting
edge of the wheel. The problem with the relief angle
cutting edges is that only one side of the wheel is used.
A problem associated with both types of angle cutting
edges is that debris builds up especially when cutting
tlre fabric because the fabric is covered with uncured
rubber.
In view of the above, it would be advantageous
to have a rotary shear wheel that does not have problems
discussed above.
SUMMARY OF THE INVENTION
A solution to the above problems may be obtained
with this inventon. This invention relates to a rotary
shear wheel having a grooved or hollowed peripheral cut-
ting surface adjacent a peripheral land. The grooved orhollowed cutting edge improves the cutting life by lntro-
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ducing a sharper cutting angle to the material and also,the land surface adjacent to the groove keeps the fabric
away from the opposite cutting edge. The land also holds
the fabric horizontal while the hollow surface forming one
of the cutting edges shears or cuts the material thus
preventing debris from forming around the cutting edge.
This is especially true when cutting rubber like materials
such as tire cord. The land, usually larger in diameter
than the cutting edge, prevents marring of the material by
the opposite unused edge. Hollow grooves allow the blade
to be reversed for additional cutting surfaces on each
side of the land. Further, resharpening the sides of the
wheel by removing stock from the side of the wheel and
resharpeniny the grooves reduced the land. However, the5 wheel can still be used for cutting fabric.
DESCRIPTION OF THE DRAWINGS
Figure l is an elevated front view of a shear
cutting wheel of the invention;
Eigure 2 is a side view of the wheel in Figure
1;
Eigure 3 is an elevated front view of another
shear wheel of the invention;
Figure 4 is a side view of the wheel in Figure
3;
Figure 5 is an elevated front view of another
shear wheel of the invention;
Figure 6 is a side view of the wheel in Eigure
5.
DESCRIPTION OF THE INVENTION
Shown in Figures 1 and 2 is a rotary shear or
cutting wheel 1. The wheel or disc 1 has an axial center
bore ~ for mounting -the wheel l on a shaft of a rotary
shear bias cutter of the type used in the art. The ele-
vated ~ront view as shown in Figure 1 illustrates the
wheel 1 with a plurali-ty of projecting arcuate or scallop-
ed rim segments about the periphery. As shown in Figure
2, the wheel l has peripheral grooves 4 and 5 about per--
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ipheral land 6. The grooves 4 and 5 preferably are con-
tinuous and form the peripheral cutting edges 3 at the
intersection of the side 7 and 8 with adjacent grooves 4
and 5 respectively.
Shown in Figures 3 and 4 is a rotary shear or
cutting wheel 11. The wheel ll has a center bore 12 for
mounting the wheel 11 on a shaft of a rotary shear bias
cutter of the type used in the art. The elevated front
view as shown in Figure 3 illustrates the wheel 11 with a
plurality of projecting segments and cutting edges 13
about the periphery. As shown in E'igure 4 the wheel 11
has peripheral grooves 14 and 15 about land 16. The
grooves l~ and 15 preferably are continuous and form the
cutting edges 13 at the intersection of the side 17 and 18
with adjacent grooves 14 and 15 respectively.
Shown in Figures 5 and 6 is a rotary shear or
cutting wheel 21. The wheel 21 has a center bore 22 for
mo~mting the wheel 21 on a shaft of a rotary shear bias
cutter of the type used in the art. The elevated front
view as shown in Figure 5 illustrates the wheel 21 with a
plurality of projecting lobes or saw tooth cutting edges
23 about the periphery. As shown in Figure 6 the wheel 21
has peripheral grooves 24 and 25 about peripheral land 26.
The ~rooves 24 and 25 preferably are continuous and form
the cutting edges 23 at the intersection of the side 27
and second side 28 with adjacent grooves 24 and 25
respectively.
The wheels 1, 11 and 21 can be used on right
handed or left handed machines. The wheel can be used to
cut fabric using the cutting edges at one side of the
wheel and then reversed. For example, and referring to
Figures 5 and 6, a bed knife 30 is mounted adjacent the
wheel side 7. The fabric 32 is cut as the cutting ed~es
rotate past the bed knife. After a time period, the wheel
can be reversed. In other words side 8 of the wheel is
adjacent the bed}~nife.
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Thè grooves 4, 5, 14, 15, 24 and 25 need not be
continuous but are on the portion of the periphery used
for cutting. For example and with reference to Figure 5
material e.g. tire cord 32 (shown only in Figure 5) is
moved from right to left and the wheel rotates in a clock-
wise direction. Moving in this direction the surface 34
- of the cutting edge does the severing. After a time
period the bed knife 30 is adjusted for the wheel rotating
in a counterclockwise direction and the cloth moving from
left to right, or the wheel is mounted on a machine having
the material moving from left to right viewed in Figure 5
to sever the fabric 32 using cutting edges 36.
The wheels of the invention can be used with
only one groove along side a land. However, usin~ two
grooves and a land therebetween permits reversing of the
wheel, as discussed above, without debris collecting on
the rim cutting edge, e.g. the cutting edge formed at the
intersection of the side of the wheel and adjacent groove.
However, one groove and a land allow also for wheel rever-
sal in which cutting with one side takes advantage of thegroove and cutting with the opposite side is similar to
the prior art 90 or relie~ angle cutting edge. The land
prevents marking of the surface of the tire cord as i-t is
being cut because the land adjacent the cutting edge is
preferably higher or has a larger diameter, thereby moving
the fabric away from the opposite cutting edge.
The wheel can be made in a~y manner. For example
and referring to Figures 5 and 6, a 16 lobe type solid
carbide wheel having a 21~" bore and 6'' Dia. and ~2'1 thick.
On the peripheral surface grooves 24 and 25 of a radius of
1" and a 3/16" land 26 therebetween are formed~ The
grooves can be any dimension or shape e.g. a depression
formed by a radius or V-shape or flats adjacent and spaced
below the land. The larger the radius the smaller the
3~ land for a given wheel thickness. The land surface pro-
duced is slightly greater in diameter than the cutting
edge. This assures the material will not be marred on the
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unused edges. The principle of the invention can be used
on straight edge shear cutters, e.g. a straight member
pivoted at one end or also for a guillotine type. The
groove and land combination or groove-land-groove combina-
tion may be used. Further, the land can be coated with arelease coating.
The groove may extend from one cutting edge to
the other. For example Figures 3 and 4 would have one
groove replacing grooves 14 and 15 and land 16. In this
case the debris would not collect on the cutting edge but
may mar the material from the unused cutting edge. The
grooves of the invention prevent debris pickup because
during cutting the material is supported at the cutting
edge and other adjacent surface of which can be the land
or other edge or surface which provides a space between
the fabric and the bottom of the groove. For the groove-
land-groove rim there is a space between the fabric and
bo~tom of the groove and after the cut, the material is
further spaced from the cutting edge by the higher land.
The wheels are usually rotated at a speed greater
than the speed of the fabric when both are compared to
llnear displacement. This speed results in debris build-
ing up on the prior art wheels.
