CERTAIN IMPROVEMENTS IN THE MACHINERY FOR SAWING TIMBER, AND IN THE MODE OF APPLYING POWER TO THE SAME
Year: 1836

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MACDOWALL, of Johnstone, in the County of Renfrew, and of Manchester, in
the County of Lancaster, Engineer, send greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-fourth day of June, in the year of our One thou-
sand eight hundred and thirty-six, and in the sixth year of His reign, did,
for Himself, His heirs and successors, give and grant unto me, the said John
Mac Dowall, His especial license, full power, sole privilege and authority, that
I, the said John Mac Dowall, my executors, administrators, and assigns, and
as such others as I, the said John Mac Dowall, my executors, administrators,
and assigns, should at any time with, and no other, from time to time and at
all times during the term of years therein expressed, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN THE
MACHINERY FOR SAWING TIMBER, AND IN THE MODE OF APPLYING POWER TO THE
SAME;" in which said Letters Patent is contained a proviso, that I, the said
John Mac Dowall, shall cause a particular description of the nature of my
said Invention, and in what manner the same is to be performed, to be
inrolled in His Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited Letters
Patent, as in and by the same, reference being thereunto had, will more fully
and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
John Mac Dowall, do hereby declare that the nature of the said Invention,
and the manner in which the same is to be performed, is particularly described
and ascertained in Drawings hereto annexed, and to the following explana-
tion thereof, that is to say:-
My Invention of certain improvements in the machinery for sawing and
cutting timber, and in the mode of applying power to the same, consists:-
Firstly, in an improved construction or arrangement of machinery for sawing
and cutting timber into planks or boards.
Secondly, in a modification of the same, suited to the sawing or cutting of
"balks" or logs of heavy timber into "scantlings" or boards; and,
Thirdly, in the adaptation of a steam cylinder and piston to each of the
said cutting frames, for the purpose of independently driving its machinery.
By this arrangement of the machinery each sawing frame is converted in a
separate engine, and is perfectly distinct from the adjoining sawing frames,
and is capable of being worked or stopped at the pleasure of the operator,
without affecting any other of the said frames contiguous to it; and it will be
perceived that by this arrangement each machine may be driven faster or
slower than the others, as the qualities or natures of the various kinds of
timber under operation may require. These improved machines may be used-
(when not employed in cutting) as ordinary steam engines for driving other
machinery by various modes, as placing a pulley on the main driving shaft
of the engine, which, by having a strap passed round it, may either be mado
to drive circular saws or for other light works. In case of this improved
arrangement of sawing machinery being constructed without the steam cylin-
der and piston, it may be actuated by an ordinary stationary steam engine,
there being a fast and loose pully mounted upon the main shaft, and a strap
leading from the actuating part of such stationary engine being connected to
the said driving pully.
In order that these improvements may be clearly understood, I have attached
to this Specification two Sheets of Drawings, exhibiting the machinery in
complete elevation and sectional views, and have marked the same with
several letters of reference, which respectively point out similar parts in all
the Figures. The first Sheet represents the saw frame, which I intend to be
employed to saw or cut "deals" or small timber into such boards or planks
as may be required. The second Sheet exhibits the "balk frame," or that
which I propose to employ for cutting or sawing heavy balks or logs of timber
into planks or thicknesses, called scantlings or boards.

page_text: In Sheet 1, Figure 1 represents a front elevation of my improved machine
for cutting light timber, and which I call the "deal frame;" Figure 2 is an
end elevation or side view, taken at the left hand of Figure 1; and Figure 3
is a partial sectional elevation, taken vertically at the dotted lines A, B, in
Figure 1. The standards or main upright framings of the machine are
shewn at a, a, bolted to the foundation, and otherwise firmly secured in their
places by the flanges cast on them, and they are also bolted to the main beams
that support the flooring 6, 6, thus dividing the machinery between the upper
and lower apartments, the one of which contains the engine or driving power,
while the other is occupied by the machinery which more immediately operates
upon the timber. The cylinder of the steam engine, by the agency of which
the sawing machinery is to be driven, is shewn at c, and it is supplied with
steam in the usual manner, through slide valves contained in the valve box
or steam chamber d, d, being fed or charged with steam from the boiler
through the main steam pipe e and the induction pipe f, and from which box
or chamber the steam is discharged by the eduction pipe g into the waste
steam pipe h, h, after its elastie force has been exerted upon the piston. The
main driving shaft i, i, is mounted upon pedestals or bearings fixed upon the
top of the upright castings or standards a, a. This shaft carries two fly
wheels j, j, two excentrics 1 and 2, and also two disc crank plates 1, 1, in
which are fixed the crank pins m, m, connected by the links or rods p, p, to
the shaft n, n, carrying the frame of saws o, o, which travel in the slides or
guide pieces o*, o*, attached to the frames a, a. It will be seen that while
the excentric k 1 is working the slide valves, which admit and discharge the
steam to and from the cylinder c, the excentric k 2 is imparting motion to the
spur wheels q, q, for the purpose of feeding or leading forward the timber by
the means of the link or rod r, r, and ratchet or click s, s, driving the ratchet
wheel and pinion u, which is keyed upon the same carrying stud or bearing.
These spur wheels 9, 9, which are of rather a fine pitch, give a slight pro-
gressive motion to the timber under operation by means of the system of
mitre wheels and shafts v, v, v, v; and it will be perceived that those of the
four lower pairs of mitre wheels that are in vertical positions are mounted
upon the ends of shafts carrying the indented iron feeding rollers w, w, which
by the above arrangement of the gearing all receive an equal progressive.
motion simultaneously, and thus feed in the timber shewn at x, x. By these
the timber in its progress through the machine or sawing frame is gradually
advanced and presented to the teeth of the saws as they are driven up and
down by the reciprocating action of the piston rod y. It will also be under-

page_text: stood that the extent of progressive motion given to the feeding rollers
through the agency of the system of gearing above explained, may be varied
and adjusted by the click or ratchet s being caused in its receding movements
to escape over a greater or less number of teeth of the ratchet wheel t, and
thus produce a quicker or slower advance of the timber according to the
nature of its grain or the number of saws which are acting upon it. The
governor by which the supply of steam to the steam chamber or valve box is
regulated is placed at the top of the machine, and is of the ordinary con-
struction, the working parts of the governor being attached to the circular
plate or disc of metal, which is driven by the friction of the periphery of
the revolving collar 1, keyed upon the main shaft. This mode of driving the
governor simply by friction is preferred, because it admits of ready adjustment
by sliding the collar nearer toward or farther from the centre of the plate,
thereby regulating the speed of the governor as may be desired by tho
operator or engineer, whenever it is necessary to vary the speed of the engine
to suit the different qualities of the timber to be operated upon.
Having now described the general construction of my improved sawing
frame, I proceed to shew the mode of putting the same into operation; let
it be understood that I prefer the engine for communicating the power to be
upon the high-pressure principle, and that the engine shewn in the Drawing,
Figure 1, 2, and 3, is supposed to be upon that construction, representing
one of about seven horses power, and which will be generally found sufficient
to operate upon deals and such like ordinary timber. This engine is shewn in
that position called "the half stroke," and is drawn upon a scale of ono inch
to the foot. The engine being first started or put in motion in the ordinary
way, by opening the throttle valve which is placed in the induction pipe f, and
thus admitting the steam or other clastic vapour, its expansive force will causo
the piston y to rise, and by the cross head 2, 2, and side links 3, 3, will draw up
the shaft n, n, carrying the frame of saws o, o, and thus, through the connecting
rods p, p, will drive the crank plates 1, 1, round, and thereby communicate
rotary motion to the main shaft i, i, which will impart its impetus to the fly
wheels j, j, and at the same time cause the excentrics 1 and 2 to revolve,
the excentrick1 giving a reciprocating motion to the slide valves through the
rod 4, the links 5, 5, and shaft 6, and thus, as the piston works up and down
in the cylinder in the ordinary manner, it will clearly be perceived that the
necessary reciprocating action will be given to the frames containing the
system of saws 0, 0, 0; these saws are, of course, adjustable in their respectivo
franies, so that any number may be employed, and also set at any required

page_text: distance apart. It has been before stated that as the engine is in operation,
the other excentrick 2 will also cause the timber to advance to the teeth of
the saws, as required by the system of gearing which works the four indented
feeding rollers w, w, w, w. It will also be perceived by reference to Figure 1,
that each of the vertical shafts v, v, have a feather or raised key 7 upon their
surface in order to carry the horizontal mitre wheels round with them, and
at the same time to allow those mitre wheels to be raised and lowered (whilst
running) upon the shaft in case of any inequalities upon the surface of the
timber under operation causing the upper feeding rollers w, w, to rise or fall,
as the boss of these pair of horizontal wheels is elongated and has a groove
turned upon it in order to embrace the end of the shaft of the feeding rollers,
as shewn at 8. Ordinary feeding tables with delivering rollers are placed in
front of the machines or sawing frames in order to conduct the "deals" or
timber to be cut on to the plates g, g, upon which they are supported while
under the operation of cutting; and upon this plate, at the feeding end or
front of the machine, there is placed a central guide piece or "fence" 10,
against which the "deals" are to be pressed by the springs 11, 11, having
friction rollers at their ends for this purpose. These springs are adjusted,
or the tightness of the pinch regulated, by the small winch and screw 12,
and similar tables are placed behind the machines to receive the timber after
it has been cut into boards. It will be seen that there are a pair of weights
13, 13, suspended from the shafts of the upper pair of feeding rollers w, w,
by the rods 14, 14, in order to keep them down upon the top edge of the
timber with sufficient pressure to resist the upward lift of the saws when
cutting. These weights are also suspended in the centre by a small chain
and pully from the shaft 15, and at one end of this shaft is a ratchet wheel 16,
the top of which has mortices cut in it for the purpose of receiving a small
crow or other bar, in order to lift the weights and top rollers when required.
Having described the construction of the first machine, called the "deal
frame," it only now remains to point out the difference which exists between
it and the "balk frame," consisting principally in the strength of its
construction, with a modification of the mechanism for advancing the timber
through the machine, dependent, of course, upon the greater degree of labour to
be overcome in cutting or sawing heavy balks or logs of timber in comparison
with "deals" or such like light timber. In Sheet 2, Figure 1 represents a
front view of the "balk frame" with the engine, upon a scale of three-fourths
of an inch equal to one foot, and shewn at the "down stroke" or end of the
cut; Figure 2 is a side elevation representing the right-hand side of Figure 1;

page_text: and Figure 3 is a partial sectional elevation, taken vertically at the dotted;
lines A, B, in Figure 1. Now, it will be seen that the principal features of
novelty in this machine are the same as bave already been described with
reference to the deal frame in all its material parts, such as the general:
arrangement of the mechanism, but being upon a more extended scale, and:
necessarily of a much more powerful construction; and, as in the before-
mentioned machine, a, a, represents the main framing or upright standards-
of the machine, which are bolted to the foundation and to the flooring b, b;
c, c, is the steam cylinder; d, d, the valve box or steam chamber; c, the main
steam pipe for conducting the steam to the valves, through the induction:
pipe f, and which is discharged through the eduction pipe g to the waste
steam-pipe has heretofore. The main driving sliaft i, i, also carries two
fly wheels j, j, and the two excentrics 1 and 2, which are likewise intended.
to actuate the slide valves through the links 5 and shaft 6, and the feeding
apparatus or timber carriage by the links 7, 7, keyed upon the shaft 8. The
two crank plates 1, 1, carrying the crank pins m, m, are also carried round by.
the ascent and descent of the shaft n, n, carrying the frame of saws 0, 0,
running up and down in the slides or guide plates o", o, and this shaft n, n,
is connected to the crank pins by the side links, or connecting rods p, p,
exactly upon the same plan as the above-described machine. It will be scen
that the principle alteration in the arrangement of the machinery.in this
engine or sawing frame consists in a different mode of advancing the timber
to, tlie teeth of the saw, in order that the log or balk may be cut into the
required planks. or scantlings. This is effected by the following contrivance:―
The log.or balk-of timber is placed upon a frame of woodwork, or carriage
suitably constructed-to-receive the same, and shewn at q, q, and running upon
friction rollers placed in bearings, bolted down upon sleepers, extending along
each side of the machino or sawing frame, and of such a length as tho
dimensions of ordinary logs or balks may require. This framing or carriage
has a toothed rack formed upon its under surface, into which the pinions
10, 10, work; these pinions are attached to a shaft 11, and upon one end of
this shaft is a toothed wheel-12, so: geared as to give motion to the small
pinions; this wheel being keyed upon the same shafts with the ratchet or
feeding wheel 13, 13, which is actuated by the ratchet 14 upon the end of the
rod or arm-15, being put in motion by the rotation' of the excentric / 2, as
before described, thus actuates the whole of the gearing, and causes the timber.
carriage, and with it the log or balk, to advance in its progress through the
machine or sawing frame. The log in its advancement towards the teeth of

page_text: the saws bears upon the antifriction roller 16, and is kept in its place upon
this bearing (that is, prevented from being lifted by the ascent of the saws)
by the weighted levers 17, 17, and upright arms 18, 18, carrying the friction
rollers 19, 19. The balk of timber is kept firmly in its place by the grip or
holdfast 20, which is securely bolted to the end of the timber carriage, and
has a screw and winch for the purpose of adjusting the balk to the centre of
the sawing frame. I have represented in Figure 1 of this Sheet a Diagram,
drawn in dotted lines, of a mode of opening or dividing a log at the same
time another balk is under the operation of sawing in the machine. The log
or balk is to be placed upon cross bridles upon the side of the carriages (or
it may run upon a separate carriage), and there are two wrought-iron arms
extending from the top and bottom of the frame o, o, carrying the system of
saws, which arms are designed to carry a single saw to cut or divide the log,
and thus prevent the necessity of disarranging the series of saws which have
been properly adjusted in the sawing frame when it is only desired to make a
single cut. This plan of mounting the saw may also be very advantageously
adopted for the purpose of cutting or sawing veneers instead of using the
ordinary circular veneer saws, and in this case the saw must be attached to a
bevilled strengthening plate, as common circular saws for cutting or sawing
veneers from timber are generally mounted.
Having now described the nature of my said Invention, and in what
manner the same is to be performed, it only remains for me to point out
the particular features of novelty; I therefore wish it to be understood that I
consider,―
First, the arrangements of machinery for sawing or cutting planks and
balks or logs of timber, as exhibited in the Drawing, to be essentially new,
and constituting one of the features of my Invention.
Secondly, I claim the combination of a steam cylinder and piston with the
said machinery, for the purpose of driving it; and,
Thirdly, I claim the employment of the said machinery as an impelling
engine for driving other machinery, or as a sawing frame, separately or
combined.
But I also wish it to be understood that I do not intend to confine myself
to working the piston by steam alone, but mean to embrace also any other
elastic vapours or gases capable of exerting elastic force, when applied to
effect the objects, as described; nor do I mean to adhere strictly to the forms
or dimensions of the steam cylinders shewn in the Drawings, nor to their
precise situations, as it will be evident that the cylinder and piston or driving

page_text: power may either be applied over or below the frames containing the saws,
and either in a horizontal, vertical, reversed, or any other position which may
be preferred; that they may either be stationary, oscillating, or rotary,
according to the pleasure of the operator, but I have shewn that which I
prefer and consider most applicable to the purpose.
In witness whereof, I, the said John Mac Dowall, have hereunto set my
hand and seal, the Fifth day of December, in the year of our Lord
One thousand eight hundred and thirty-six.