Note: Descriptions are shown in the official language in which they were submitted.
lZ9Z9ZS
WOOD TENDERIZIRG APPARATUS AND M~THOD
This invention relates generally to tenderizing wood
and more particularly to an incisor roller with cutting
formations formed integral therewith for making incisions
in wood veneer or lumber. The invention is further
directed to an incisor apparatus incorporating one or more
of the foregoing rollers.
Wood tenderizing is well known and consists generally
of making incisions in wood lumber cr veneer for the
purpose of improving the drying rate in green lumber,
improving the treatability of the wood and in the case of
veneer providing uniform strength characteristics which
re5ult in reduced buckling and splitting and improved
handling on automatic lay-up lines. For various examples
of methods and apparatuses for tenderizing veneer,
reference may be had to the following:
United States Patents:
4,219,060, issued August 26, 1980 to KATSUJI HASEGAWA;
3,678,974, issued July 25, 1972 to J.C. O'BRIAN;
4,486,963, issued December 11, 1984 to MASARU KOIKE et al;
: 4,473,099, issued September 25, 1984 to MASARU KOIKE et al;
3~29~9~
l,469,154, issued September 4, 1984 to MASARU KOIKE et al;
4,442,876, issued April 17, 1g84 to MASARU KOIKE et al;
4,318,433, issued March 9, 1982 to RALPH D. AMUNDSEN;
4,137,956, issued February 6, 1979 to LLOYD FOBERG.
While a number of methods and apparatuses are
currently used for incising most all, to applicant's
knowledge, employ a plurality of incising teeth that are
fixed to rollers or platens. A~ a typical example of
separately attached incising teeth attention is directed to
the aforementioned U.S. Patents 4,318,433 and 4,137,956.
There are a number Or drawbacks and limitations to
currently available inci~ors and that is they have a high
initial capital cost and also relatively high maintenance
costs. The high capital ¢ost comes from manufacturing
difficulties of fixing a large number of incising teeth to
a backing of some nature with extremely hlgh tolerances.
The close or high tolerances are required if there is to be
accomplished any semblance of a close and consistent
pattern to achieve the desired effect. High maintenance
costs are encountered because as the teeth become dull they
must be sharpened from time to time or replaced and both
represent si~able problems.
lZ9Z9ZS
Important considerations in the design of an incisor
are the geometry of the incising teeth and the frequency
and pattern of incisions produced by the incisor.
One object of the present invention is to provide an
incising roller that is relatively inexpensive and simple
to manufacture and one which can be readily produced and
reproduced consistently in a variety of different patterns.
Another ob~ect of the present invention is to provide
an incising roller that may be formed in a number of
different patterns each of which is intended to give
particular desired results dependent upon the type and
¢hara¢teristi¢s of the material or veneer to be inci~ed
and/or characterlstics desired for the incised material.
Another ob~ect of the invention is to provide an
incising roller wherein the incising teeth are integrally
formed with the roll.
Another ob~ect of the present invention is to provide
an incising apparatus for veneer wherein there is at least
; one incising roller having a large number of incising teeth
formed integrally with the roller.
While incising of veneer can be a single step as in
single line operation independent of other processing
operations, another object of the present invention is to
combine the incislng operation with other operations. For
~Z9Z~25
example, a combined operation can be forming the veneer
u3ing a lathe and incising it at the same time and if
desired additional means can be provided for controlling
the thickness of the veneer. An incising and drying
operation is yet another intended combined operation.
In accordance with one aspect of the present
invention there is provided an incisor roll for use in
incising wood comprising an elongate roller and a plurality
of knife-like cutting formations projecting from the said
roller, said cutting formations be formed integrally with
the roller and defined by and separated from one another by
grooves in the roller surface. The cutting formations are
arranged in selected, predetermined patterns and each has a
~harpened straight line cutting edge of finite length
extending in predetermined direction relative to the axis
of the roller dependent upon the intended usage of the
incising roller.
In the preferred form the plurality of cutting
formations are separated by grooves formed in the outer
surface of the roller and wherein at least some of the
grooves are in a spiral path around the surface of the
roller. At least some of the spiral grooves preferably
¢riss-cross one another and may be of equal or unequal
number in opposite directions to one another as will be
~Z9~9"5
discussed in more detail hereinafter. The cutting
formations preferably result fro~ machining or cutting by
a lathe operation, grooves in the outer surface of a
roller. For example they are formed by cutting "V"-shaped
grooves in a right hand screw-like fashion along the roller
and then cutting a left hand screw pattern. By varying the
depth of cut, the width of the cut and/or the pitch angle
of the screw a variety of tooth geometrics and frequency
patterns can be produced. The grooves can if desired be
formed by a grinding pattern. As an alternative to
machlning the grooves can be result from casting or molding
and then finished by a grinding or machine cutting
operatlon to provide the requisite knife-like cutting edge.
In accordance with another aspect of the present
invention there is provided an incising apparatus
comprlsing two parallel oppositely disposed rollers between
which a sheet of veneer can pass and be pressed
therebetween and a plurality of cutting formations on the
surface of at least one of said rollers for making slits in
a selected pattern in said veneer, said cutting formations
being spaced apart from one another and located between
grooves at least some of which spiral around the surface of
the roller to cross other grooves and thereby define and
separate the cutting teeth fronJ one another.
'
12~Z925
The invention is illustrated by way of example in the
accompanying drawings wherein:
Figs. 1A & 1B are top plan views of a portion of
incisor rollers of the present invention showing two of
many different possible patterns;
Figs. 1C & lD are end elevatiorla~ views of respective
Figs. 1A and 1B;
Fig. 2 is a part sectional view along line 2-2
of Fig. 1A;
Fig. 3 is a part sectional view along line 3-3 of
Flg. 1A;
Fi8. 4 is a view essentially along line 4-4 of Fig.
1A showing a single tooth in enlarged side view;
Fig. 4A is a top view of Fig. 4;
Fig. 4B is a side elevational view of Fig. 4;
Fig. 5 is a partial front elevational view of a
veneer incising machine;
Fig. 6 is a sectional view along line 6-6 of Fig. 5;
Figs. 7A to 7E are enlarged partial sectional views
essentially along line 7-7 of Fig. 6 illustrating veneer
incisors with inaising rollers of the present invention
with different patterns and in different combinations;
Figs. 8 to 14 are face views of veneer incised using
rollers with incising teeth arranged in various patterns
lZ9Z9Z5
- 7 -
and in which Fig. 8 illustrates slit-like cuts in the front
face of a portion of a veneer sheet using apparatus with a
roller configuration of Fig 7A;
Fig. 9 is the scoring pattern in the front face of
the veneer using the roller configuration of Fig 7B;
Fig. 10 is the back face of the veneer of Fig. 9;
Fig. 11 is the front face and scoring pattern using
the roller configuration of Fig. 7C;
Fig. 12 is the scoring pattern in the front face of a
portion of a veneer sheet using the roller configuration of
Fig, 7~;
Figs. 13 and 14 are the scoring patterns respectively
ln the front and rear face of a portion of a veneer sheet
using the roller configuration of Fig. 7E;
Fig. 15 is a view similar to Fig. 7B but with some
modifications;
Fig. 16 is an incising pattern in veneer using the
arrangement of Fig. 15;
Fig. 17 illustrates a "big bar" lathe.
The broadest aspect of applicant's invention is
illustrated in Figures 1 to 4 and simply consists of a
roller of particular construction and design for use in
incising wood veneer or lumber. The roller is preferably
a shaft of appropriate material (instead of a shaft it can
l~9Z925
-- 8
be a thick walled cylinder or a shaft of composite
material) with grooves in the outer surface and spiraled
thereabout with some grooves crossing others leaving
therebetween projections which constitute cutting knives
for forming slits in the wood. The cutting knives can be
in any one of numerous different shapes and patterns only
some of which are illustrated.
In another aspect of applicant's invention there is
provided a veneer incising apparatus that employ various
different combinations of press and incising rolls some of
which are illustrated in Figs. 7A to 7E and 15.
Another aspect of applicant's invention is
lllustrated in the form of three different embodiments
represented by Fig. 17 and consists of the combined
operations of cutting a ribbon of veneer from a log and
incising the veneer using incising rollers of the present
invention.
Referring to the drawings, Figs. 1A and 1B are end
portions only of two different incising rollers of the
present invention, Fig. 1A representing a shaft roller 10
and Fig. 1B a pipe or thick walled cylinder roller 10A.
Also the incising roller of Fig. 1A is for use in apparatus
of a single step operation while roller 10A of Fig 1B is
for use of combined operations. In each instance there is
~z9Z~2S
a journal mounting shaft 11 at each of opposite ends of the
roller. In each instance the incisor roller is formed by a
machine operation using a metal lathe having an appropriate
cutting tool or by milling. The cutting tool is usually
ground with a sharpness angle of 30 or 60, but it could
be square, rectangular, etc. The operation is similar to
screw thread cutting but in the present case the threads
run from each end of the roller toward the other end and
criss-¢ross to form the separate teeth. The tooth pattern
is determined by various parameters, as will be more fully
described hereinafter, such as pitch, number of thread
starts, angle of cutter, depth of cut and lead angle.
Generally, multiple thread starts are used and these would
have a lead angle of about 15 for a veneer incisor roller
and about 80 in veneer lathe incising rollers. When there
are multiple thread starts, they are equally spaced about
the circumference, for example, a double thread has two
starts diametrically opposite i.e. at a point 180 apart.
An 8-start thread would have 8 single threads starting at
45 apart. The preferred thread pitch is 1/4", but a
smaller or larger pitch could be used.
The pattern of the incising teeth is created by the
criss-crossing grooves and they are in the form of parallel
rows of teeth when similar grooves or thread starts are
~Z9Z9"S
- 10 -
turned from each end of the roll. There are spiraling rows
of teeth about the roller surface when the number of thread
starts turned from one end is different from the number cut
from the opposite end. The incising teeth of these rollers
are perpendicular to the roller axis when the grooves cut
have a lead angle of about 15 . Such type of incising
roller is illustrated in Fig. 1A which consists of a
plurality of incising teeth 12 integrally formed with the
shaft roller 10. Each tooth has an elongate knife cutting
edge 13 that extends partially about the periphery of the
roller in a direction transverse to the shaft axis of
rotation designated X-X. Ea¢h tooth 12 has four faces
designated respectively 14, 15, 16 and 17. Faces 14 and
16, (on opposite sides of the tooth~ are as a result of two
spaced apart parallel grooves cut spirally in one direction
in the face of the roller in the milling or lathe
operation. Similarly faces 15 and 17 result from another
two separate ~paced parallel grooves (i.e threads) cut in
the face of the roller but spiral thereabout in an opposite
direction. Referring to Fig. 1A parallel spaced apart
grooves 18 and 19 spiral about the roller defining
opposite faces 14 and 16 on a plurality of incising teeth
in a row A. Grooves 20 and 21 spiral in an opposite
lZgZ925
direction around the shaft forming tooth faces 15 and 17
respectively.
Grooves 20 and 21 are cut as would a left hand screw
thread while grooves 18 and 19 are as a right hand thread.
The grooves 20 and 21 are spaced apart and parallel to one
another and the plurality of teeth 12 are aligned in a
second row designated B that spirals about the roller.
Because grooves 18 and 19 intersect grooves 20 and 21 there
is provided a plurality of individual incising teeth each
with a sharpened cutting edge.
The shape of each tooth is determined by the pitch
designated P in Fig. 1A, the number of thread starts
(designated S in Fig. 1C~, the angle of the groove cutter,
the depth of cut and the lead angle.
The ranges and considered best within the range of
theRe parameters are as follows:
lZ92~2S
INCISOR PARAMETERS
Ranges Probable Best
Pitch 1/8" to 1/2" (1/4" and 3/8")
No. of thread starts (from 1 to 10 (1,2,8,9)
each end of roll)
Angle of cutter 20 to 60 (30 or 60)
Depth or Cut (normallyup to 1/2" (3/8" to 1/2")
but not necessarily greater than veneer thickness)
Lead angle 0 to 90 ( to 15
incisor i.e.
single operation
(75 to 90)
lathe and inclsor
i.e. combined
operation
The parameters of the incising rolls illustrated
respectively in Figs. 1A and 1B are as follows:
Fie. 1A Fig. 1B
Pitch P = 1/4" 1/4"
Lead Angle = 15 80
Roll Diameter = 5 1/4" 5 1/4"
Number of Threads
Start S = 8 (Fig. 1C) 8
The roll diameter can be of most any size. The
foregoing size 5 1/4" was found through experiments
1292925
operative but such size is not to be construed as limiting.
It will be observed the cutting edges of the teeth in Fig.
1A are transverse to the roll axis while in Fig. 1B they
are parallel to the roll axis. In the latter embodiment
the grooves are formed by milling rather than turning and
such embodiment is for use in a combined operation of
incising and lathe forming the veneer.
A veneer incising machine is partially shown in
Figures 5 and 6 and includes a frame 100 having a pair of
parallel spaced apart rollers journalled therein by
bearings 101. The upper roll 102 and/or the lower roller
roll 103 are drlven by a suitable power source and/or
drive train generally designated by reference 104. The
upper and/or lower respective rolls 102 and 103 can be
incising rolls and in the case illustrated in Fig. 5 the
upper roll 102 is an incising roll and the lower roll 103
is a rubber fa¢ed back up roll. The rolls are closely
adjacent to one another providing a nip 105 therebetween
for receiving a sheet of veneer SV (see Fig. 6).
Different roll patterns and different combinations of
rolls can be used to provide different characteristics of
the incised wood depending upon its use and intended
purpose for the incising. Figs. 7A to 7E are cross-
se¢tions effectively along line 7-7 of Fig. 6 illustrating
1292925
- 14 -
a few different roll pattern combinations and some veneer
incising patterns resulting therefrom are shown in Figs. 8-
14.
Fig. 8 is the incising pattern (referred to herein as
pattern 1) on the front face of a veneer sheet that results
from the roll combination of Fig. 7A.
This pattern exemplifies an incisor pattern on roller
102 produced under condition (a) by 9 multiple thread
starts from each end and a pitch of 5/16", thus forming a
60 incising tooth with 15 lead angle and tooth depth of
5/16~o
A similar pattern is produced under condition (b)
where the tooth parameters are as follows: pitch 1/4", a
30 inclsing tooth, 8 multiple thread starts and a depth of
1/Z". This results in longer and sharper teeth than in the
foregoing and more frequent incisions across the veneer.
In each instance back-up roll 103 i5 a rubber faced roller.
Tests performed for conditions (a) and ~b) provided
the following:
The reduction in drying rate was larger for (a) than
for (b) with (a) giving as much as a 15% reduction for
drying time while (b) gave a reduction of 10%. The benefit
with respect to treatability was higher for (b) than for
(a) with (a) showing a 50% improvement in penetration in
~Z~Z925
- 15
spruce veneer over non-incised veneer while (b) gave a 75%
improvement in penetration over a control. With respect to
blows delamination was reduced by 50% when 10% M/C
(moisture content) incised veneer was used over similar M/C
non-incised veneer.
Figs. 9 and 10 are the patterns respectively on the
front and rear face of the veneer from the roll combination
of Fig. 15. This is sometimes referred to herein as
pattern 2 which also can be referred to as the reverse bend
pattern. In this embodiment of the apparatus the upper and
lower respective rolls 102 and 103 have incising teeth
resulting from the following parameters lead angle of 0,
pitch 3/8", depth 3/8~', 60 tooth on bottom roll, 30 tooth
on top roll. This pattern gave exceptional réduction in
blows during plywood pressing. When 10% moisture content
veneer was used all control panels blew while none of the
panels produced from incised veneer blew or delaminated (a
blow results when gas is entrapped between veneer layers
and is under sufficient pressure as to overcome the glue
bond and thus results in a separation of the layers. With
respect to treatability Pattern 2 was slightly les~ than
Pattern 1. The bottom roll 103 of Fig. 15 (which al~o has
the same knife pattern as roll 103 of Fig. 7B~ has
effectively a plurality of side by side spaced apart
129Z925
-- 16
grooves perpendicular to the roller axis that define the
cutting knives i.e. the grooves do not spiral about the
roller. The ribs between the grooves are continuous about
the roller. In Fig. 15 the top roll 102 has the ribs
cross-cut by grooves that preferably spiral about the
roller whereby each rib provides a plurality of cutting
teeth spaced about the periphery of the roller.
Pattern 3 is shown in Fig. 11 and results from the
combination of an upper roller 102 as in Fig. 7C and
described above with a lower rGll or anvil 103 that is
coated with a resilient material (rubber) and with a smooth
surfa¢e, In terms of drying, treatability and blows
Pattern 3 wa~ less effective than Pattern 1 or Pattern 2.
Fig. 12 illustrates Pattern 4 resulting from the
apparatus of Fig. 7D. The incisors were made using a
machined upper roller 102 and an anvil lower roll 103
having a smooth resilient surface. The incising roller 102
was made by cutting 3 threads per inch in one direction and
;~ 4 threads per inch in the opposite direction. This
produced a 60 tooth.
A 30 incising tooth renders essentially the same
pattern. Benefits in drying were for the 60 tooth 12% and
for the 30 tooth 8% reduction in drying time. Performance
-` i292~ 5
with respect to treatability and blows was better than
F'attern 1.
Pattern 5 is shown in Figs. 13 and 14 which are
respectively the front and rear face of a veneer sheet
incised with the roll combination of Fig. 7E. Each roller
102 and 103 has incising teeth made as in the previous case
by cutting 3 threads per inch in one direction and 4
threads per inch in the opposite direction. As with
Pattern 4 the benefits for drying, treating and blow
reduction were all high but the power requirement for
Pattern 5 was substantially less than for Pattern 4.
In all of the embodiments described in the foregoing,
with the exception of Fig. 7B, the teeth are formed by
grooves that criss-cross, i.e. the groove lead angle is
greater than 0. In Fig 7B the groove lead angle is 0,
i.e. the grooves are parallel to one another and
perpendicular to the roll axis. A further illustration of
this is shown in Fig. 15 and the resultant incising pattern
from the use thereof is shown in Fig. 16. Referring to
Fig. 15 the top roll 102 has parallel ribs 102B extending
thereabout each having an apex with an included angle of
30 and spaced apart at 3/8" intervals. The ribs 102B are
separated one from the other by a portion 102C, i.e.
adjacent ribs are separated by a flat bottomed groove.
~z9Z92S
- 18
Each rib is interrupted about the periphery of the roller
by cross-cut grooves that preferably spiral about the
roller i.e. each rib is interrupted thereby each rib
provides a plurality of cutting knives.
The bottom roll 103 in Fig. 15 has side-by-side
abutting ribs 103B each having an apex included angle of
60. Ribs 103B are transverse to the roll axis and have
depth of 3/8" as do ribs 102B. Again the lead angle is 0.
The ribs 102B are intersected as mentioned by grooves
that can be parallel to the roll axis or spiral thereabout
providing a plurality of teeth on each rib that are
¢ir¢umferentially spa¢ed about the roll. This spacing
results in a pattern Or slits in the veneer shown in Fig.
16 arranged in row~ and ~pa¢ed from one another lengthwise
and ~ideways of the sheet. Referring to Fig. 16 these
rows, designated X, Y AND Z, are shown each having slits W
of about 3/4" in length and spa¢ed from the next in the
; same row by about 1/2". The row~ are spaced 3/8" apart.
The ribs 103B offset longitudinally along the roll from
ribs 102B cause reverse bending and in addition to the
slits cut in the veneer there is a crack from the bending
whi¢h i5 shown as a wavy line designated G between rows X-Y
and between the rows Y-Z.
129Z9;~5
- 19
Applicants incising roll, as described in the
foregoing, can be used in an incising apparatus where the
individual sheets of veneer or pieces of wood are incised
or alternatively they can be used in a combination process.
Figure 17 shows diagrammatically and by way of example a
veneer lathe with one incising roll of the foregoing type
mounted on the nose bar thereof. The lathe of Figure 17 is
what is known in the trade as a "big bar" type lathe having
a nose bar 300. An incising roll 301 of the present
invention is journalled for rotation on the big bar 300 for
rotation about an axis parallel to the axis of rotation of
the bolt L. The big bar lathe is a spindle type lathe and
a~ the log or bolt L is rotated a ribbon of veneer 304 is
cut from the bolt by a knife 305 downstream from the point
of contact of the incising roll 301 with the bolt.
In the foregoing there is described an incising roll
of switable material (normally metal) having teeth formed
integrally with the roll by cutting grooves in the roll
surface. The roll can be a solid shaft or formed from a
center core of any material and covered with a metal sleeve
or be a thick walled cylinder. In either embodlment and as
a further embodiment the incising roll can have the grooves
at least partially filled with a resilient compressible
material such as rubber, neosprene, or the like. If
lZ92925
- 20 -
desired the knife-like cutting edges on the roller can be
embedded in, i.e. below the outer surface of the resilient
c03ting when the latter is in its normal at rest
uncompressed state. When incising this resilient coating
is in rolling pressural engagement with the surface of the
piece being incised.
By way of example, Figure 1D in roller quadrant R,
there is illustrated a compressible elastic coating T that
only partially fills the grooves that define the teeth and
thus the knife-like cutting edges project therebeyond. In
quadrant S of the same figure the cutting edges of the
inclsing teeth are shown embedded in the compresslble
elastic coating T. A coating T is also shown in Fig. 15
which may be on one or both or neither of the rolls.
In the foregoing, the grooves are described as being
formed in the roller by a machining operation. There are,
of course, other alternative ways obvious to those skilled
in the art of making the incising rolls with the grooves.
For example, the grooves can be formed during molding or
casting of the roller or by a roll-forming operation and
then machined or ground to the desired sharpness for the
cutting edges. Also, it will be obvious to those skilled
in the art, the roller can be made with strong but perhaps
a relatively soft material, for example aluminum, which is
~29Z9~5
_ 21 -
easy to machine or form or shape and then coat the surface
with a hard material. There is no real load on the teeth
other than a compressive load during operation.
It should also be pointed out applicant's tooth shape
is extremely important as there results no bending during
use as is the case in the prior art. Each tooth is
effectively a double wedge shape best illustrated perhaps
by reference to Figures 4 and 4A. With reference to Figure
4, if one is to assume the cutting tooth 12 fully impales
the veneer which is a thickness approximately equal to the
maximum depth of the tooth, there is a gradual penetration,
during rotation of the roller, of the cutting edge 13.
During this gradual penetration of the tooth there is also
a gradua~ widening, i.e. the second wedge as illustrated in
Figure 4A, of the faces 16 and 17 (or if the direction is
reversed, faces 14 and 15). This double wedging action has
a tendency to avoid deflection when encountering more dense
pieces of wood, for example where there are knots. Since
there is no bending on the teeth strength is not a major
criteria for forming the teeth, but instead having a
material which will maintain a relatively sharp knife-like
cutting edge during use.
';
