Note: Descriptions are shown in the official language in which they were submitted.
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TRANSPORTABLE CANTING MILL
SPECIFICATION
BACKGROUND OF THE INVENTION
This invention relates to canting mills. Many patents in canting technology
are complex and
disclose huge systems requiring factory facilities to contain and use.
DESCRIPTION OF THE PRIOR TECHNOLOGY
There exist systems for producing square cants by using opposing pairs of
chipping canters to
chip and cant lumber in a single pass through the apparatus, using various
hydraulic arms and
rollers to adjust for the position of the log being worked.
The technology of manufacturing cants from irregularly curved logs often uses
adjustable jigs,
boxes or frames containing chipping heads, and vertical/horizontal circular
saws guided by fluid
power systems under the control of computers which receive sensor and scanner
input on log
dimensions in real time. Some such cant manufacturing systems use pairs of
chippers and saws,
and computer control to refine the cutting and canting during multiple trips
through the milling
assembly.
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SUMMARY OF THE INVENTION
This transportable canting mill uses hydraulic powered feeder rollers mounted
with brackets
onto extendable hydraulic arms to pass a log through two pairs of opposing
chipping cylinders to
hydraulic powered extraction rollers, all within a wheeled container that can
be used at or near a
logging site to turn substantially round, raw timber into easily stacked and
hauled lengths of
lumber that is square or rectangular in cross section. The sides of the
wheeled container act as a
frame to support the bases of the hydraulic arms. A separate engine
compartment below an outlet
for the lumber allows fuel and sparks to be kept separate from the chipping
area.
In a preferred embodiment, the invention provides a transportable canting mill
for shaping
lumber from logs and producing wood chips, comprising:
a first feeder roller assembly having at least two pair of feeder rollers
driven by hydraulic motors,
each feeder roller mounted at an end of an extendable hydraulic arm, the arms
arranged such that
the feeder rollers can cooperatively grip a log by applying opposing forces to
the circumference
of the log;
a second feeder roller assembly having at least three feeder rollers driven by
hydraulic motors,
each feeder roller mounted at an end of an extendable hydraulic arm, the arms
arranged such that
the feeder rollers can cooperatively grip the log by applying opposing forces
to the circumference
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of the log;
the first and second feeder roller assembly being mounted adjacent to each
other in a log entrance
portion of a frame;
a first pair of opposing coarse chipper cylinders driven by motors and mounted
on extendable
hydraulic arms such that opposite sides of the log can be canted as the log is
fed between the
opposing coarse chipper cylinders of the first pair;
a second pair of opposing coarse chipper cylinders driven by motors and
mounted on extendable
hydraulic arms at right angles to the first pair of opposing coarse chipper
cylinders, such that
opposite sides of the log that are perpendicular to the opposite sides canted
by the first pair of
opposing coarse chipper cylinders can be canted as the log is fed between the
opposing coarse
chipper cylinders of the second pair;
the first and second pairs of opposing coarse chipper cylinders being mounted
in a mid portion of
the frame;
a first extraction roller assembly having four feeder rollers driven by
motors, each feeder roller
mounted at an end of an extendable hydraulic arnl, the arms arranged such that
the feeder rollers
can cooperatively grip a log by applying opposing forces to four perpendicular
sides of the log;
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a second extraction roller assembly having four feeder rollers driven by
motors, each feeder roller
mounted at an end of an extendable hydraulic arm, the arms arranged such that
the feeder rollers
can cooperatively grip the log by applying opposing forces to four
perpendicular sides of the log;
the first and second extraction roller assemblies mounted in a log exit
portion of the frame;
in which the first and second feeder roller assemblies have four feeder
rollers each; and in which
the first and second feeder roller assemblies are computer controlled in
combination with real-
time sensing of log shape to adjust the position of the feeder rollers, in
order to accommodate
curved logs being fed into the transportable canting mill;
the first and second feeder roller assemblies are mounted within a few feet of
each other in the
frame yet in combination with high pressure capability in the hydraulic arms
keep the log
cooperatively gripped and fed into the transportable canting mill while
preventing unwanted
pivoting of the log;
the coarse chipper cylinders have rows of staggered teeth to allow wood chips
to escape from
between the log and the respective coarse chipper cylinder;
the coarse chipper cylinders are approximately 200 millimeters in diameter and
approximately
600 millimeters long;
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the position of the first and second pairs of opposing coarse chipper
cylinders are adjustable with
respect to the log and each other by means of the hydraulic arms on which are
mounted the first
and second pairs of opposing coarse chipper cylinders, to allow variation of
cant size on the log;
the position of the first and second pairs of opposing coarse chipper
cylinders can be finely
adjusted in real-time by computer-control in combination with feedback sensing
of the
transportable canting result on the log;
the frame has a sloped, trough floor such that wood chips produced by canting
of the log fall and
slide to a chip extraction location;
a conveyor belt is mounted below the opposing coarse chipper cylinders to
carry wood chips
away;
the frame is a wheeled tandem trailer, with reinforced steel plate at the
hydraulic arm bases;
an engine is mounted to the frame and drives a pump to supply fluid pressure
for the hydraulic
arms in order to control the position and pressure of the hydraulic arms on a
log passed though
the mill, and supplies fluid pressure to power to motors driving the feeder
rollers and the coarse
chipper cylinders;
by which cants ranging from 100 millimeters to 600 millimeters can be formed
on a log fed into
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the transportable canting mill.
This portable canting mill can be moved from one small business logging or
timber processing
site to the next. 'The canting mill will produce a rough or finished product
to be sold or used
post and beam homes, railway ties and any other specialty lumber products such
as doors and
windows.
The powering system consists of hydraulic cylinders, motors and pumps. The
pumps can be run
from a motor such as a 6 cylinder 3406 Cat diesel motor (Cat is a trademark of
Caterpillar Inc.) A
suitable size for the milling cylinders would be 200mm round by 600mm long.
When they are
rotated under power at approximately 3200 RPM by hydraulic motors and pumps,
typical bark
and wood is chipped from the inserted timber in order to obtain wood chips and
shaped lumber.
The hydraulic arms are used for rapid control and strong gripping of the
timber and the lumber.
The hydraulic motors for rotating the feeder rollers and the chipping
cylinders are provided
instead of electric motors to reduce fire hazard in the chipping area. That
area will rapidly
become suffused with sawdust, which could ignite by a spark given off by an
electric motor. It is
likewise important that the main motor be kept separate from the chipping
area, again in order to
reduce fire hazard.
The log is placed on tapered feed rollers. The feed rollers are run by
hydrualic motors which are
compressed by hydrualic cylinders that feed the log with so much pressure on
the log. fChe log is
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run straight into opposing milling cylinders. Once the log has gone through
the milling wheels it
will have four square sides to it (the cant). There are flat rollers that will
run the log straight out
of the canting mill. to guide it out of the milling wheels.
The chips from the milling cylinders fall to the bottom of the transportable
canting mill, where a
sloped directing surface guides them to a conveyor that will load them into a
chip truck box.
There are important economies in having the chipping done as close to the
logging site as
possible. The lumber can be stacked more efficiently and with greater
stability on a logging
truck. The chips do not need to be transported to a separate chipping factory,
only to be
retransported to a chip processing facility. The chips can likewise be
contained and transported
more effectively when removed from the raw timber and conveyed into a chip
truck.
DESCRIPTION OF THE DRAWINGS
Figure 1 is a side view of the canting mill of this invention.
Figure 2 is a top view of the canting milt, with the roof cut away.
Figure 3 is an end view of the transportable canting mill, showing a log being
inserted into the
canting mill, and a conveyor belt ready to convey chips away.
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Figure 4 is an end view of the feeder rollers of the transportable canting
mill.
Figure 5 is an end view of the chipping cylinders of the transportable canting
mill.
DETAILED DESCRIPTION
Referring to Figure 1, a log 1 can be placed on the inlet roller bed 2 and
pushed into the log inlet
3, where the first pair of feeder rollers 4 and 5 grip the log 1 from above
and below and roll it
toward a second pair of feeder rollers (near one shown at 6) and thence to a
third pair of feeder
rollers 8 and 9. When in the grip of three pair of feeder rollers under
pressure, the log will not be
moved significantly sideways, unless intended for control to adjust for
irregularities such as
curving in the log 1, as it is passed through the first pair of chipping
cylinders (near one shown at
10. The sides of the log 1 (near side shown at 12) are canted by the first
pair of chipping
cylinders and the log is forcibly rolled toward the second pair of chipping
cylinders 14 and 15,
which cant the top and bottom of the log 1. The log 1 is thence passed to the
first pair of
extraction rollers 16 and 17, the second pair of extraction rollers (near one
shown at 18), and the
third pair of extraction rollers 20 and 21, to the extraction outlet 22, and
onto the roof 23 of the
compartment containing the engine 24, which drives the hydraulics control
system 25. Chips
from the chipping cylinders 10, 14, 15 fall to the sloped bottom 26 and of the
container and out
the chip outlet 27 for gathering and shipping. The transportable canting mill
can be parked with a
tandem trailer stand 28 and towed to a new site with hitch 29, as it is
provided with wheels as at
30. The roof 31 and likewise the sides and floor of the mill are of
sufficiently strong and
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reinforced steel that due pressure from the hydraulic arms as at 32 and 33
will not buckle the
roof, floor and sides.
Referring to to Figure 2, the inlet roller bed 2 allows the log 1 to proceed
into the gripping feeder
rollers 4, 6, 7 , 8, where it is fed to the side chipping cylinders 10 and 11,
the top (and bottom,
unshown) chipping cylinders 14. After all four sides of the lumber are canted,
the lumber is
passed through the extraction rollers 16, 18, 19 and 20 through the outlet 22
and onto a roof
(through which in dotted lines are shown the engine 24 beneath, which drives a
hydraulic pump
41 and thence the hydraulics control system 25).
Referring to Figure 3, the tandem trailer stands 28 and 42 support the inlet 3
end of the canting
mill, where the log 1 is visible, having been inserted via the inlet roller
bed 2. The wheels 30 and
44 are visible behind the stands 28 and 42, ready to roll when needed. The
sloped bottom 26
allows chips to exit the canting mill at the chip outlet 27. The sides 45 and
46 are of steel plate
where needed to support the hydraulic arm bases inside the canting mill.
Referring to Figure 4, the top feeder roller 4 and the bottom feeder roller 5
are driven by fluid
motors 51 and 52 respectively. Likewise the left feeder roller 7 and the right
feeder roller 6 are
driven by fluid motors 53 and 54. The top feeder roller 4 is positioned by
means of hydraulic
arms 32 and 82, with opposing pressure from the bottom feeder roller 5 being
exerted by
hydraulic arms 33 and 83. A top bracket 91 holds the fluid motor 51 and the
feeder roller 4 on an
axle driven by the fluid motor 51. A bottom bracket 92 holds the fluid motor
52 and the feeder
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roller 5 on an axle driven by the fluid motor 52. The feeder rollers are
tapered as at 60, to better
accommodate the circumference of the log 1. Pointed bumps as at 61 are used to
assist in
gripping the log 1 and passing it along firmly to the chipping cylinders.
Referring to Figure 5, the fluid motors 81, 82, 83, and 84 that power the
chipping cylinders are
larger than those for the feeder rollers, as there is considerable force
required to chip and strip the
log 1 into the desired four-sided shape. The brackets 101 and 102 hold the
motors 81 and 82 and
the corresponding chipping cylinders 14 and 15 on axles. The chipping
cylinders have rows of
staggered teeth as at 70 and 71. The staggering and having spaces between the
teeth allows the
chips to more readily exit from between each chipping cylinder and the log 1.
The view is from
the log exit end of the canting mill, and the left and right chipping
cylinders 10 and 11 can be
seen behind the top and bottom chipping cylinders 14 and 15.
The within-described invention may be embodied in other specific forms and
with additional
options and accessories without departing from the spirit or essential
characteristics thereof. The
presently disclosed embodiment is therefore to be considered in all respects
as illustrative and not
restrictive, the scope of the invention being indicated by the appended claims
rather than by the
foregoing description, and all changes which come within the meaning and range
of equivalence
of the claims are therefore intended to be embraced therein.
