IMPROVEMENTS IN WOOD SAWING MACHINERY
Year: 1876

page_text: LETTERS PATENT to Daniel McDowall, of Johnstone, in the County of Renfrew,
North Britain, Engineer, for the Invention of "IMPROVEMENTS IN WOOD
SAWING MACHINERY."
Sealed the 21st October 1876, and dated the 28th April 1876.
PROVISIONAL SPECIFICATION left by the said Daniel McDowall at the
Office of the Commissioners of Patents on the 28th April 1876.
DANIEL MCDOWALL, of Johnstone, in the County of Renfrew, North Britain,
Engineer. "IMPROVEMENTS IN WOOD SAWING MACHINERY."
This Invention has for its object to combine the practical advantages of continuous
sawing with the convenience and saving of time and labor that with ordinary
reciprocating saws arise from the simultaneous action of several saws in one
frame.
The
In carrying out the Invention two, three, four, or more endless band saws are
arranged in one machine, and in one modification each band saw is stretched
vertically upon a pair of pulleys on a standard, each pair of pulleys being fitted with
the requisite tension apparatus, and with a separate pulley for a driving belt.
several standards are set upon horizontal guide beds formed on the sole plate of the
machine, and have screw spindles arranged in connection therewith for adjusting
them on their guide beds, in a direction transverse to the line of feed or progressive
movement of the timber being sawn, so that the saws can be set to cut any desired
thickness. The several saws are by preference arranged so that those cuts of a
series which are nearer the outside of the timber are made in advance of the other
cuts. Tables and rollers are provided to support the timber on each side of the
space in which the saws act; and the timber is fed or progressively moved towards
the saws in a continuous manner by any suitable known continuous feed motion.
In other modifications two or more band saws, each stretched on its pair of pulleys,
may be held by one standard or frame piece; the adjusting of the saws for thickness
of cut being obtained by mounting the shafts of the pulleys in eccentric bushes
which can be turned by worm and worm wheel gearing or levers.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
.
the said Daniel McDowall in the Great Seal Patent Office on the 27th October
1876.
DANIEL MCDOWALL, of Johnstone, in the County of Renfrew, North Britain,
Engineer. "IMPROVEMENTS IN WOOD SAWING MACHINERY."
My said Invention has for its object to combine the practical advantages of con-
tinuous sawing with the convenience and saving of time and labor that with
ordinary reciprocating saws arise from the simultaneous action of several saws in
one frame.
In carrying out my said Invention two, three, four, or more endless band saws
are arranged in one machine, and in one modification each band saw is stretched
vertically upon a pair of pulleys on a standard, each pair of pulleys being fitted
with the requisite tension apparatus, and with a separate pulley for a driving belt.
The several standards are set upon horizontal guide beds formed on the sole plate
of the machine, and are adjustable in a direction transverse to the line of feed or
progressive movement of the timber being sawn, so that the saws can be set to cut
any desired thickness. The several saws are by preference arranged so that those cuts
of a series which are nearer the outside of the timber are made in advance of the
other cuts. The timber is supported on tables and rollers and is progressively moved
tówards the saws by a suitable continuous feed motion. In other modifications two
or more band saws, each stretched on its pair of pulleys, may be held by one-standard
or frame piece, the adjusting of the saws for thickness of cut being obtained by
mounting the pulleys in or on eccentric bearings which can be turned by worin
wheel gearing or levers.
And in order that my said Invention and the manner of performing the same
may be properly understood, I hereunto append three Sheets of explanatory Draw-
ings to be herein-after referred to and representing modifications of my improved
wood sawing machinery. In these Drawings the same reference numerals are used
to mark the same or like parts wherever they are repeated.
Figure 1, on Sheet 1 of the Drawings, is a plan; Figure 2 is a side elevation, and
Figure 3 an end elevation of one modification of my improved wood sawing
machinery; and Figures 4, 5, and 6, on Sheet 2 are respectively a plan, an end
elevation, and a side elevation of the feed motion and other details of the machine
which are not fully shown on Sheet 1. The machine comprises a sole plate 1, on
which are mounted four standards 2, carrying each a pair of pulleys 3, 4, having
band saws 5 stretched vertically upon them. The upper pulleys 3 are carried by studs
6 on slide blocks 7, which are adjustable in vertical guides in the standards 2, and
these slide blocks 7 have formed on them projecting pieces 8, through which spindles 9
are screwed. The spindles 9 pass up through blocks 10, and have fixed on them
hand wheels 11 for adjusting the slide blocks 7, and the bosses of the wheels
bearing against the blocks 10 which are jointed to the ends of levers 12 centered
on brackets 13 on the standards 2. The other ends of. the levers 12 have
weighted rods 14 attached to them, which tend to raise the sliding brackets 7
and pulleys 3, and give the requisite tension to the band saws 5. The lower
pulleys are fitted on shafts 15 supported in fixed bearings in the standards 2,
which shafts 15 also carry driving pulleys 16 actuated by belts 17 from
pulleys 18 on a counter shaft 19 at one side of the machine. The standards 2
are set upon horizontal guide beds 20, formed on the sole plate 1 of the machine,
and have screw shafts 21 arranged in connection therewith for adjusting them on
their guide beds 20 in a direction transverse to the line of feed or progressive
movement of the timber being sawn. Guide pulleys 22, carried by brackets 23,
adjustable on the sole plate 1, are provided to regulate the tension of the belts 17
when the standards 2 are moved. The standards 2 have fixed to them both above
and below the timber brackets 24, which carry pieces 25 having small brackets 26.

page_text: fitted to them so as to be adjustable transversely, and in these brackets 26 are held
small rollers 27, against which the backs of the saws bear. The upper pieces 25 are
movable vertically in guides formed in the brackets 24, and can be fixed at any
desired position to suit the depth of timber by bolts in the brackets passing through
slots in the slide pieces 25. The timber is supported on each side of the space in
which the saws 5 act by rollers 28 carried by brackets 29 fixed, to tables 30, which
are supported on frames 31 resting on the sole plate 1, and one side of the timber
bears against and is guided by a series of antifriction rollers 32, carried by a
frame 33 which is adjustable horizontally in a guide piece 34 supported by the
table 30. This guide piece 34 has formed on it a boss 35, through which is passed
a screw spindle 36 carried in bearings 37 on the table 30, and the guide 34 and
frame 33 can be moved across the table to suit the thickness of the timber by means
of a hand wheel 38 on the end of the screw spindle 36, a clamp 39 being provided to
fix the guide piece. 34 at any desired position. The timber is fed or progressively
moved towards the saws in a continuous manner by means of a grooved or fluted
roller 40 bearing against the side of the timber, and which is carried by a
bracket 41 fitted so as to be moyable on a swivelling joint to the end of a projecting
arm 42 on a column 43. The fluted roller 40 has fixed on it a pulley 44 driven by a
chain 45 from a second pulley 46 on the upper end of a vertical shaft 47 passing
down through the column 43, and on the lower end of the shaft 47 is keyed a worm
wheel 48 in gear with a worm 49 on a horizontal shaft 50 supported in bearing in
the frames 31 and carrying pulleys 51, which are driven by a belt 52 from pulleys 53
on the counter shaft 19. The pulleys 53 are loose on the shaft 19, and are con-
nected thereto by a friction cone clutch 54, acted on by the forked arm of a bell-
crank lever 55, the other arm of which is connected by a rod 56 to the lower end of
a hand lever 57 centred on the frame 31. The column 43, which passes through a
projection formed on the table 30, is supported in a pedestal 58 fixed to the sole
plate 1, and is made telescopic to permit of the fluted feed roller 40 and its con-
nections being raised or lowered as desired, pinching screws 59 being provided for
fixing the upper movable part of the column. The feed roller 40 on the outer end
of the arm 42 is pressed against the timber by the tension of a chain 60 attached to
the end of a lever 61 on the lower end of the column 43, and this chain 60 passes
round and over a series of guide pulleys 62 to a weight 63.. The lever 61 has
jointed on its end a toothed segment 64, which is guided by the spindle of the
pulley 62 passing through a slot in the segment 64, and when the feed motion is
thrown out of action by moving the hand lever 57 a worm 65 is put into gear with
the toothed segment 64, this worm 65 being fast on a spindle 66 carried by a
boss formed on a lever 67, which is jointed to a bracket 68 fixed to the sole plate 1,
and which is also connected to the hand lever 57. A hand wheel 69 on the end of
the worm spindle 66 is provided for moving the segment against the action of the
weight 63 and thus moving the feed roller 40 away from the timber.
.
Figure 7, on Sheet 3 of the Drawings, is a plan, and Figures 8 and 9 are side and
end elevations of a second modification of my improved wood sawing machinery.
In this machine each standard 2 carries on each side of it a pair of pulleys 3, 4, on
which two band saws 5 are stretched. The pulleys 3, 4, run on pins or studs 70,
formed eccentrically on short shafts 71 carried by the slide blocks 7, and these
shafts 71 have formed on them levers 72 by which the bushes are turned so as to
adjust the saws 5 for different thicknesses of cut. The pair of levers 72 of each saw
are parallel to each other and are connected by rods 73 so as to be moved together.
The upper pulleys 3 are fitted with tension apparatus similar to that herein-
before described with reference to Figures 1, 2, and 3, and a screw shaft 21 is also
provided for adjusting the standard 2 on the guide bed 20, such adjustment being
desirable when two or more standards, each with a pair of saws, are combined in one
machine.
Having thus particularly described my said Invention and the manner of per-
forming the same, I have to state that I do not restrict myself to the precise details
herein described or delineated, but that what I believe to be novel and original and

page_text: claim as the Invention secured to me by the herein-before. in part recited Letters
Patent is
1. The combining of two or more endless band saws in one machine, and so as to
operate on the same piece of timber, as herein-before described.
2: The making of the standards of multiple band sawing machines adjustable on
horizontal-beds, substantially, as and for the purpose herein-before described.
3. The mounting of the pulleys of multiple band sawing machines on eccentric
pins or studs which can be adjusted for different thicknesses of cut, substantially as
herein-before described.
In witness whereof, I, the said Daniel McDowall, have hereunto set my hand
and seal, this Twenty-fifth day of October, in the year of our Lord One
thousand eight hundred and seventy-six.
DANIEL MCDOWALL. (L.S.)