Note: Descriptions are shown in the official language in which they were submitted.
~L~8841
The present invention is an improvement on that type Of
wood member cut~ing apparatus shown in prior United States
Patents 3,080,895; 3,229,732 and 3,380,494, issued to George L.
~layo .
In common with these prior art apparatuses, the present
apparatus is used for cutti~g wood members used in the manufactur-
ing of wooden roof and floor trusses and for many other purposes
where precision repetitive cutting o- members on a production
basis is required. As in the prior patented apparatuses, the
present apparatus includes a stationary base frame, a rirst gang
oF power saws and first conveyor means mounted near one end of
the base frame, a carriage on the base frz~e movable toward and
away from the first gang of saws and first conveyor means, and a
second gang of saws and second ccac.ina conveyor means mountec o~
the carriage. rhe present a~paratus, like the prior patented
ap~aratuses, includes a driving system -or the conveyor means and
t~e carriage and a means to gage the lengths of wood members
being cut in the apparatus.
Tne prior patented apparatuses, ~hile quite efficient
in the overall, possess certain definite drawbacks which are
ully eliminated in the new apparatus here described. The most serious of
these drawbacks is the comparatively limited mobility of the cut-
oEf saws in the t~o gangs and the complete lack of any independent
vertical adjustment of the saws in the gangs. As a result, the
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saws of the prior patented apparatuses are limited to 90 degrees
of rotationor pivoting to avoid interference with the workpieces
being cut, and are also restricted to cutting wi~h only one
segment of the circular blade of each saw.
These restrictions are eliminated as here described
by the provision of an independent vertical adjustment for
each saw in the two gangs of saws within a vertical datum or
" reference plane common to each saw gang. This critical adjustmentl
iltogether with an expanded double pantograph precision support and ,
~~guidance mechanism for each saw greatly increases the rotational
mobility of each saw to such an extent that each saw independent-
ly can rotate a full 180 degrees around the axis of a chord.
across the saw blade lying in the vertical datum plane for such
blade.
This improved arrangement enables two segments on
' diametrically opposite parts of each saw hlade to be utilized for
`cutting wood members, instead of one segment only, thus increasin~,
the number of angle cuts which can be made during each pass of a
wood member through the apparatus and also increasing the variety
of types of cuts which can be made. The improved arrangement
enables the addition of another saw in each of the two gangs,
compared to the arrangements in the prior patented apparatuses,
where individual saw rotation is limited to 90 degrees.
Another drawback of the prior art which the new
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apparatus overcomes is the use of a very long torque shart for
driving the conveyor system. Such a long shaft is di~ficult to
support and is likely to be damaged resulting in poor operation
of the conveyor system and expensive repairs. To overcome this
difficulty, an improved conveyor drive
eliminates entirely the use of a long tor~ue shaft in the corvev-
or system. Instead, the drive employs an arrangement o~ electro-
magnetic clutch devices associated with c~ain and sprocket gear-
ing powered directly by a single drive unit to operate both the
stationary and carriage mounted conveyor components in unison or
independently as particular requirements dictate to greatly
increase the precision and versatility of the con~7eyor system.
The improved arrangement enables the use of separable awYiliary
wor~ conveyors dlrectlv driven by the drive means o~ the primary
conveyors when long wood members are involved.
Another important improvement feature over the prior
art is the provision of a precision wood
member measuring device on the front of the base frame of the
a?paratus which can automaticall~ stop the carriage and thus
position the two saw gangs for cutting wood memDers o- any
reauired length with high precision.
The improved more versatile conveyor system also
enables certain compound angle cuts to be made on wooder members
w`hich are not possible in the prior art~
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88~
More particularly in accordance with the invention
there is provided, a wood member cutting apparatus comprising
a base, a movable carriage on the base, saw gangs and wood
member conveyors cooperatively mounted on the base and carriage,
an integrated power drive means for the carriage and for said
conveyors on the base, and a precision wood member length
measuring and automatic carriage stop mechanism on the base,
said mechanism comprising a rotational shaft extending longitudi-
nally of the base, means to adjust the shaft axially along the
~0 base to a precision position, a.plurality of a~ially equidis-
tantly spaced and circumferentially equidistantly spaced radial
stop pins on the shaft, and circumferential lockable locator
means for the shaft enabling one radial stop pin at a time to
be.positioned on the shaft in the path of movement with the
actuator element of a limit switch on the movable carriage to
automatically stop the carriage at a position on the base corres-
ponding to a required length measurement of a wood member being
cut by said apparatus. Tne circumferential lockable locator
means may be on the means for adjusting the shaft axially, which
itself may comprise a manual screw threaded linear distance
indicator means along the axis of the shaft.
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Specific embodiments of the invention will now be
described having reference to the accompanying drawings in
which:
Figure 1 is a side elevation of an apparatus for
cutting wood members but with parts omitted for clarity.
Figure 2 is a fragmentary plan view of the apparatus
in Figure 1, with parts omitted.
Figure 3 is an enlarged front elevation of an
individual saw supporting, ~djusting and rotational movement
means.
Figure 4 is a rear elevation, on a reduced scale, of
the elements shown in Figure 2 and showing particularly the
independent vertical adjusting means for each saw with the saw
positioned at a low elevation.
Figure 5 is a similar view of the vertical adjusting
means with the saw positioned at a high elevation.
Figure 6 is a schematic perspective view of two saw
gangs and their associated wooden member conveyors in relation
to vertical and horizontal datum planes.
Figure 7 i5 a front elevation of the elements shown
in Figure ~.
Figure 8 is a partly schematic perspective view of
an integrated precision drive system for primary and auxiliary
conveyors and for the carriage which supports one-half of the
conveyor system and one saw gang.
Figure 9 is a partly schematic plan view of the
primary conveyors showing their operation for enabling
compound angle cutting of wood members.
Figure 10 is a perspective view of an automatic wood
member measuring device.
Figure 11 is an enlarged transverse vertical sec~ion
taken on line 11-11 of Figure 10.
Figures 12, 13 and 14 are similar views taken on lines
12-12, 13-13 and 14-14 of Fi~gure 10.
Figure 15 is a fragmentary front elevation of the
measuring device fine adjusting means.
Figure 16 is a plan view of a truss constructed from
wooden members of the type which the present apparatus can
produce with precision on a production basis.
Figure 17 is a plan view of another form of truss
made from members which the new apparatus can produce with
precision.
Figures 18, 19 and 20 are perspective views of
individual members utilized in the trusses shown in Figures 16
and 17.
Figure 21 is a perspective view of a surveyor's
stake which the apparatus can produceO
Figure 22 is a fragmentary perspective view of a
wooden member having a compound angle cut which the apparatus
can produce.
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De t,a ~ led Descri~tion -
For reference throughout the description~ the rront of
the apparatus is that which is viewed in Figure 1 and its rear is
that which is at the top of Figure ~ and t~e ~ar side o~ Figures
6 and 8. The right and left hand ends Qf the apparatus are tne
right and left hand ends in Figures 1, 8 a~d 10.
Since the referenced prior ~ayo patents ~ully disclos~
basic components of tha app~ratus, such co~ponents a~ ar2 common
to t'ne prior patents will be brierly described, whil2 new and
impro~ed components.will be fully described.
Referring to the drawings in detail where~n liXe
numerals designate like parts, the apparatu~ comprises an
elongated stationary base ~rame 30 having a ~ransv~rse stationary
platform means 31 at one end thereo~ and a carriage 32 movably
8~
mounted thereon near its opposite end, the carriage being
movable toward and from the platform means 31 under influence
of mechanism to ~e described.
Attached to the stationary platform means 31 is a
first gang of saws, namely three saws 33, 34 and 35, having
their circular blades 36, 37 and 38 lying in a common vertical
datum or reference plane 39, Figures 6 and 7. ~lso attached
to the platform means 31 is a relatively stationary primary
conveyor 40 including a lower section 41 and an upper section
~0 42 between which conveyed wood members are fed rearwardly from
the front to the rear of the apparatus. The axis of primary
conveyor 40 is perpendicular to the longitudinal axis of base
frame 30 and perpendicular to the path of movement of carriage
32 on the base frame 30.
Attached to carriage 32 and moving therewith at
proper times along the base frame 30 toward and from stationary
platform 31 is a second gang of saws 43, 44 and 45 having
their circular blades 46, 47 and 48 lying in a common vertical
datum plane 4~ parallel to the datum plane 39, Figures 6 and 7.
The saws 33, 34 and 35 of the first gang are mounted
on supports 50, 51 and 52 fixed on the platform 31 and the saws
43, 44 and 45 of the second gang have similar supports 53, 54
and 55 fixed to the carriage 32 and movable therewith. Also
fixed to the carriage 32 and moving therewith is a primary
conveyor 56 consisting of a lower conveyor section 57 and an
upper section 58 parallel to the conveyor sections 41 and 42.
As each saw support on the brace frame 30 and
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carriage 32 is identical, a complete descrip~ion of one support
will suffice to describe them all. Therefore, in Figures 3
through 6, the support 53 for carriage mounted saw 43 is shown
and comprises a frame 59 having its base 60 attached to the
carriage 32, not shown, and also having a head member 610
Between the base 60 and head member 61 and rigid therewith are
parallel vertical guide bars 62~ A semi-circular vertical
support plate 63 having gear or sprocket teeth 64 formed all
along its se~i-circular edge has three spaced vertical axis
~O guide bearings 65 fixed to its rear face and being in precision
guided engagement with the guide bars 62. The plate 63 and
the saw 43 and associated ~aw movement means to be described,
all attached to the plate 63, are raised and lowered vertical-
ly by a vertical axis screw shaft 66 having a crank handle 67
at the top of the support 53, the screw shaft having threaded
engagement with a drive nut 68 fixed on the plate 63. A
linear measurement scale 69 extending vertically and fixed to
the frame 29 coacts with a pointer 70 on the adjacent guide
bearing 65 to indicate the vertically adjusted position of
'O each independently adjustable saw of the system. This in-
dependent vertical adjustment feature for each of the six
saws is an important improvement over the prior art contribut-
ing to greatly increased utility of the apparatus.
On the support 53 and every other like support of
the apparatus is a supporting and constrained rotational
movement means for the particular saw, such as the saw 43.
This means is in the nature of a modified pantograph linkage
and comprises a vertical base link 71, Figure 3, fixed to the
lower portion of plate 63 along the vertical edge thereof.
A double parallelogram linkage consisting of links 72, 73, 74
and 75 interconnects the fixed link 71 with an intermediate
floating base link 76 having a powdered or idler gear 77 engag-
ing the teeth 64 of semi-circular plate 63. Pivots 78 and 79
for the two links 72 and 73 are on the stationary base link 71
and corresponding pivots 80 and 81 for the two links 74 and 75
are on the floating base link 76, the two longer links 73 and
74 of the lower double parallelogram linkage between base links
71 and 76 being shown at 82.
Above the floating base link 76, a second double
parallelogram linkage is formed by two longer links 83 and 84
pivotally connected at 85 and two shorter links 86 and 87
pivoted to the longer links at 88 and 89, the two pivots 80
and 81 also connecting the links 83 and 86 to the intermediate
floating base link 76 which separates the lower and upper
double parallelograms of the linkage.
The tops of the two links 84 and 87 are pivotally
attached at 90 and 91 to an upper moving base link 90' on which
the drive motor 92 of saw 43 is fixedly mounted. A powered or
idler gear 93 on the link 9C' engages the teeth 64 of plate 63.
~0 At least one of the gears 93 or 77 is powered by:conventional
means, not shown.
The described linkage in Figure 3 enables th~ saw 43
to pivot or rotate through a full 180 degrees between the two
phantom line positions shown where the blade 46 is horizontal
and can face downwardly or upwardly in relation to drive motor
92. One intermediate angled position of the saw 43 is shwon
in full lines in Figures 3 to 5, and the sawec~n be infinitely
adjusted to any angled position between the two extremes shown
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in phantom lines. It can be noted in Figure 3 that center
lines drawn through the pivots 90 and 91 on link 90', through
the pivots 80 and 81 on link 76, and through the pivots 78 and
79 will intersect at a point 94 on the outer face of circular
saw blade 46 and on the described vertical datum plane 49
which lies on the centar line through pivots 78 and 79. At
all points along the saw blades angular adjustment path on the
semi-circular plate 63, a chord on the saw blade 46 through
the point 94 forms the pivot or ro~ational axis for that
perpendicular saw in the common vertical datum plane 49. Such
chord on the saw blade 46 defining its rotational axis in the
datum plane 49 is shown àt 94a in Figure 6. The corresponding
chords for saw blades 47 and 48 are indicated at 94b and 94c
in Figure 6, the respective saws 44 and 45 in Figure 6 being
adjusted to vertical positions different from the position of
the saw 43, by the means described particularly in Figures 4
and 5, It is to be understood that each of the chords 9~a, 94b
and 94c, regardless of the vertical adjustment o e~ch saw in
the three saw gang always lies in the vertical datum plane 49.
Furthermore, in all rotated positions of the saw 43 or any saw
in its gang, the saw blade always rotates or pivots about the
intersection point 94 which defines the chord across the saw
blade.
A great àdvantage derived from this geometry is that
the cutting ability of each saw blade is not restricted as in
the prior art to one peripheral sagment of the blade. Because
the blade can rotate through a full 180 degrees around the
point 94, two diametrically opposite portions or segments o
each blade can be used for cutting wood members at positive or
negative angles as they are fed through the saws by conveying
means, already mentioned.
'18~
It must also be understood regarding the geometry of
the saw movement means that the pitch circle of the teeth 46
on plate 63 is centered on the point 94 which is in the datum
plane 49. The combination of the vertical adjustment-for each
saw through the mechanism show~ in Figures 4 and 5 and the
rotational adjustment through the means shown in Figure 3 great-
ly expands the mobility of each saw compared to the prior art
where all of the saws were at a common fixed vertical height
and could only rotate or pivot through 90 degrees at that
height. The versatility of the present apparatus in terms of
making a greater number of angular cuts on wooden members at a
greater ~ariety of angles is greatl~ expanded over the known
prior art apparatus.
The above-described relationships of saw blades 46, 47
and 48 and their chords 94a, 94~ and 94c within the vertical
datum plane 49 is exactly repeated with the saw blades 36, 37
and 38 of the gang of saws 33, 34 and 35 on the base frame 30.
That is to say, the blades 36, 37 and 38 have chords 95a, 95b
and 95c all lying within the vertical datum plane 39 and about
'0 which chords the several saws 33, 34 and 35 independently
rotate under influence of their double pantograph type linkages
described in detail for the one saw 43.
A hori20ntal datum or reference plane 96 important in
the setting up and precision operation of the apparatus can be
established with taut chords or the like to be exactly at right
angles to the vertical datum planes 39 and 49 and across the
tops of lower primary conveyor sec~ions 41 and 57, Figure 1.
The horizontal datum plane 96 is the plane that will define
the bottom faces of wood members passing through the machine
0 from front to back and it is in relation to this plane 96 that
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the several saws in the two gangs are independently verticallyadjusted to provide the desired sequence of cuts in conjunction
with the angular adjustment of each saw through its rotational
lin~age described relative to Figure 3. Thus, the apparatus
has more precise geometry than any prior art apparatus as a
result of the establishment of the vextical and horizontal
datum planes with precision.
The improved wood member conveycr system dispensing
with the need in the prior art for a troublesome long torque
shaft is shown primarily in Figure 8. In this figure, the two
pr~mary conveyors 40 and 56, previously mentioned, composed of
lower and upper sections 41 and 42 and 57 and 58 are illustrat-
ed. Two auxiliary removable lower conveyor sections 97 and 98
used with longer wood members to provide intermediate support
in the apparatus are also shown in Figure 8. These auxiliary
conveyor sections are removed from the system when short wood
members are being processed. In connec~ion with Figure 8,
conveyor 40 having sections 41 and 42 and auxiliary section 97
are fixed on base frame 31, whereas conveyor 56 with its
~0 sections 57 and 58 and auxiliary section 98 are mounted on and
move with carriage 32. In Figure 8, carriage 32 has a propul-
sion shaft 99, not shown elsewhere, having gears 100 thereon
which roll on guiding and supporting rack bars 101 suitably
secured to base frame 30.
The carriage and the entire conveyor system for the
apparatus is powered by a motor 102 on the base frame 30 having
a right angle gear drive 103 turnlng a transverse shat 10~ on
the base frame 30 equipped at one end with an electromagnetic
clutch 105 which can selectively be rendered active or inactive
at a push button control panel 106 on the base frame 30,
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Figure 1. The driven shaft 104 carries sprocket gears 107 and
108 engaging parallel longitudinal endless sprocket chai~s 109
and 110 which, at thelr far ends, engage idler sprockets 111
and 112 also on base frame 30. Chain 109 has a driving connec-
tion through a sprocket gear 113 with an electromagnetic
clutch 114 on carriage displacement shaft 99 which in turn has
another sprocket gear 115 thereon engaged with the chain 110~
The clutch 114, like all of the electromagnetic clutches in the
system, is under control of an operator at the control panel or
station 106. The electromagnetlc clutches are conventional
devices which also have braking capability.
Through the sprocket 107, the chain 109 is positively
driven and this chain includes a loop 116 engaging a sprocket
gear 117 on an electromagnetic clutch brake 118 connected
through a right angle gear drive 119 with another sprocket
gear 120. This sprocket gear engages and drives an ascending
endless sprocket chain 121 engaging and driving a sprocket
gear 122 having a sqùare opening to receive and drive in one
direction a square shaft 123 having a telescoping section 124
whose length may be varied between universal joints 125 and
126 in the square shaft. A sprocket gear 127 beyond the
universal joint 126 on this square shaft engages and drives
the overhead section 42 of primary conveyor 40 above the lower
section 41 which has equidistantly spaced lugs 128 thereon to
assure that the wood members are positively driven through the
saw gangs from front to back of the machine.
Ano:ther square shaft 129 below the shaft 123 carries
a sprocket gear 130 engaging the outside of chain 121 to
drive shaft 129 oppositely to shaft 123, thereby driving the
top run of lower conveyor section 41 in the same linear
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direction as the bottom run of upper section 42. Lower
section 41 is driven by a sprocket gear 131 on square shaft 129.
Auxiliàry removable conveyor section 97 is coupled with and
driven by square shaft 129 through a smaller square shaft 132
which telescopes into shaft 129 removably. Shaft 132 carries
a sprocket gear 133 to power auxiliary conveyor section 97
which is at the same elevation as lower primary conveyor
section 41. The tops of conveyor sections 41 and 97 coincide
with the horizontal datum plane 96, as best shown in Figure 1.
.0 An identical and independent drive system for the
carriage mounted conveyor 56 including lower and upper sections
57 and 58 and auxiliary removable lower section 98 is provided.
This independent drive system is also controlled from the con-
trol panel 106 whereby the carriage mounted and base frame
mounted conveyors can be powered in unison, or one can be
powered independent of the other. The drive for the carriage
mounted conveyor means thus comprises another loop 134 in
drive chain 109 operatively connected with another electrical
clutch brake unit 135, connected through a right angle gear
'0 drive 136 with an ascending chain 137 driving a square shaft
138 for powering the upper section 58 of primary conveyor 56
in the same direction as the upper section 42 of primary
conveyor 40. The lower conveyor section 57 and auxiliary
section 98 are powered through another square shaft 139
driven off chain 137 and a removable telescoping square sha~t
140 corresponding to shaft 132.
It can now be readily understood that the improved
conveyor system without a long torque shaft is not only more
adapted to processing long wood members but is more precise
and much more versatile. ~or example, with the drive motor 102
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energized and the clutches 105 and 114 activated, the carriage
32 with lts gang of saws 43, 44 and 45, their supports and the
conveyor 56 can be displaced toward or away from the stationary
platform 31 and the gang of saws and conveyor means thereon.
By deactivating clutche 105 and 114 and activating clutches
118 and 135, the two primary conveyors 40 and 56, with or
without their auxiliary sections 97 and 98, can be driven in
unison. By disabling one of the clutches 118 or 135, one
primary conveyor 40 or 56 can be halted while the other is
advanced to accomplish an askewed ad~ancement of a wood
member 141 or members through the saws for the purpose of
making compound angle end cuts thereon as distinguished from
advancing a member or members 142 through the apparatus at
right angles to theparallel conveyors 40 and 56, see Figure 9.
The versatility of the system and its lack of dependence on
any long torque shaft has been demonstrated.
The combination of carriage positioning by displace-
ment of the shaft 99 and the independent vertical ~djustments
of the several saws plus their pivotal or rotational independ-
ent adjustments enables the apparatus to produce with greatprecision on a mass production basis a great variety of long
and short wooden components, For example, Figure 16 shows a
roof truss having members 143 and 144 which are shown separate-
ly on an enlarged scale in Figures 18 and 19. Either of these
members may be cut to length and may have all of the necessary
angle cuts formed on their opposite ends in a single pass
through the apparatus. Likewise, the othe. members 145 and
146 of the truss, Figure 16, can be mass produced by the
apparatus as can a wide variety of other members with proper
adjustment of the carriage 32 and coordinated adjustments of
the saws in the two cooperatlng gangs. Whenever required, one
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or more saws in each gang of three saws can be swung to aposition where the saw blade is horizontal and then adjusted
vertically to remove the saw from action.
Figure 17 shows a floor truss or the like whose web
members 147 also shown in Figure 20 can be produced in a single
pass through the apparatus with the auxiliary conveyors 97 and
98 for long wood members removed.
Figure 21 shows a surveyor's stake 148 which can be
manufactured by the apparatus in a single pass, and Figure 22
shows another member 149 having compound angle end faces 150
which can be produced on an askewed member as shown at 141 in
Figure 9.
A final important feature shown in Figure 1 and in
Figures 10 through lS is a precision wood member measuring
attachment or assembly 151 on the front of the base frame 30.
This measuring assembly comprises a horizontal elongated shaft
152 having a plurality of collars 153 thereon at equidistantly
spaced points along the shaft, such as one foot intervals.
The shaft 152 is rotatably supported in bearings 154 and 155,
the bearing 154 being attached to base frame 30`and the
bearings 155 being attached to a rectangular measuring frame
156, in turn anchored to the base frame 30 through a bracket
157. Additional support bearings, not shown, can be provided
at intervals along the shaft 152.
Each collar 153 on the shaft 152 carries a radial
pin 158, only a few of such pins being shown in Figure 10 for
simplicity. The radial pins of successive collars 153 along
the shaft 152 are spaced equidistantly circumferentiall~ and
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~88~ .
progressively from each other so that only one pin lies in one
radial plane ~hrough the shaft 152 and no other pin is in the
same radial plane.
A carriage limit switch 159 on the carriage 32 has a
depending switch actuator 160. The shaft 152 can be rotational-
ly adjusted in its bearing to place one, and only one, pin 158
in the upright position shown in Figure 12 in the path of
movement of the carriage limit switch actuator 160 to engage
such actuator and stop the movement of the carriage 32 at a
!0 particular polnt corresponding to the desired length of the wood
member being cut by the two gangs of adjustable saws.
To facilitate adjusting the shaft 152 precisely cir-
cumferentially, a disc 161 on the shaft has circumferentially
equidistantly spaced apertures 162 therein corresponding to the
equidistant spacing of the carriage stop pins 158 around the
shaft 152. The shaft and disc 161 can be rotated relative to
a reference indicator 163 on a fixed plate 164 attached to
frame 156, and when a particular pin 158 establishing the
desired wood member length and carriage 32 stop point is up-
'0 right, a locking pin 165 on indicator 163 is inserted into the
adjacent aperture 162 o~ disc 161 corresponding to the particu-
lar required upright pin 158. That particular~pin 158, and
only that pin, will trip the actuator 160 and stop the carriage
32 at a given point to establish a precise spacing between the
saws in the two gangs to thereby cut the wood member to a
precise length.
In cases where the required length is not an even
number of feet corresponding to the spacing between the
collars 153, a fine distance adjustment scale 166 on the top
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of frame 156 is utilized. ~ scribe mark 167 on the plate 164coacts with the scale 166 to reflect a precise measurement.
An adjusting crank 168 at one end of the measuring attachment
drives a screw shaft 169 having threaded engagement with the
plate 164 to drive it in either direction along the measuring
scale 166 to provide the refined measurement for the length
of the wood member, whatever that length may be. The measuring
device is simple, convenient to use and precise. It is much
more reliable and consistent than a mere steel measuring rule
~0 or other makeshlft means. Also~ the device is automatic in
stopping the carriage 32 carrying one of the saw gangs at
precisely the desired point on the base frame 30.
The measuring device also possesses a safety feature
in the form of two stop discs 170 on the shaft 152 near its
opposite ends in the path of travel of limit switch actuator
160 at all times and in all rotational positions of shaft 152.
These two stop discs prevent any possible over travel of
carriage 32 in either direction.
.
It is to be understood that the apparatus herewith
shown and described is to be taken as a preferred embodiment
of the invention, and that various changes in the shape, size
and arrangement of parts may be resorted to, without departing
from the spirit of the invention or scope of the subjoined
claims.
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