Improvements in Band Sawing Machines.
Year: 1892

page_text: Date of Application, 15th Mar., 1892
Complete Specification Left, 15th Dec., 1892-Accepted, 28th Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in Band Sawing Machines.
I, ALLEN RANSOME of Stanley Works Chelsea London Engineer do hereby
declare the nature of this invention to be as follows:-
This invention relates to improvements in band sawing machines for logs and
other heavy timber and applies more particularly to those parts of such machines
as serve for maintaining the saw blade in its proper position on the saw pulleys when
cutting, and for putting the proper tension on it.
It should be understood that the upper wheel which carries the saw is mounted
on a shaft between 2 bearings one at each end.
In order that the cutting edge of the saw may be made to retain its proper
position on the wheels and withstand the thrust of the cut, I provide mechanism by
which the upper saw pulley can be adjusted in four different directions as follows:-
1st. The upper saw pulley and the shaft which carries it can be shifted bodily
in a fore and aft direction.
2nd. The said shaft and pulley can also be adjusted bodily in a transverse
direction.
3rd. The shaft & pulley can be tilted vertically about a point immediately in
front of the pulley.
4th. The shaft and pulley can be tilted horizontally about the same centre as
above.
The arrangements for these several adjustments are as follows:-
1st. I cut a screw on the top pulley shaft on either side of the after bearing, and
I provide two sets of lock nuts at either end of the bearing. By turning these two
sets of lock nuts in either direction it is easy to make the required adjustment and
give the upper pulley the desired overhang as regards the lower wheel.
2nd. For the second adjustment I mount the two bearings carrying the upper
pulley shaft, in slides which can be moved transversely by screws on planed faces
on the bracket which carries the wheel.
3rd. In order to give the vertical tilting motion to the top saw pulley, I mount
the slide carrying the after bearing on a cylinder sliding vertically in a socket and
provided with a screw by which the said bearing can be readily raised or lowered.
4th. The horizontal tilting motion of the top saw pulley is accomplished by
fitting the slide which carries the after bearing of the pulley shaft with a pair of
bevil wheels worked by a spindle and hand wheel so that the after slide can be
traversed independently of the fore one.
The two bearings of the upper saw pulley shaft are so socketed in their plummer
blocks that they can swivel in any direction to compensate for the varying angles
of the shaft as above described.
In order to obtain the proper tension on the saw blade my improved arrangement
is as follows:-
The upper saw pulley with its shaft and bearings is carried on a vertical sliding
bracket, the weight of which is supported on a strong vertical screw which may be
run up and down through a nut to suit saws of different lengths. This nut is
formed with two lugs or projections, one on either side, which rest upon two levers
pivotted on a pin immediately behind the saw, the levers being so formed that the
horizontal centre line of the lever passes through the pins and also through the
point of contact of the levers with the lugs on the nut in order to minimise friction.
The outer ends of these levers are connected by means of four links and a cross-
piece to another lever behind the machine and at right angles to the levers last
mentioned, the whole forming a system of compound levers of great power, and

page_text: one which allows of the sliding weight being conveniently placed and readily
adjusted.
Dated thi. 15th 1
L1000
COMPLETE SPECIFICATION.
Improvements in Band Sawing Machines.
I, ALLEN RANSOME, of Stanley Works, Chelsea, London, Engineer, do hereby
declare the nature of this invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement :-
This invention relates to improvements in band sawing machines for logs and
other heavy timber and applies more particularly to those parts of such machines
as serve for maintaining the saw blade in its proper position on the saw pulleys
when cutting, and for putting the proper tension on it.
Figure 1 is a front elevation and Figure 2 a side elevation of the machine.
It should be understood that the upper wheel A which carries the saw B is
mounted on a shaft C between two bearings D D one at each end.
In order that the cutting edge of the saw B may be made to retain its proper
position on the upper and lower wheels A and E and withstand the thrust of the
cut, I provide mechanism by which the upper saw pulley A can be adjusted in four
different directions as follows:-
1st. The upper saw pulley A and the shaft C which carries it can be shifted
bodily in a fore and aft direction.
2nd. The said shaft and pulley can also be adjusted bodily in a transverse
direction.
3rd. The shaft and pulley can be tilted vertically about a point immediately in
front of the pulley.
4th. The shaft and pulley can be tilted horizontally about the same centre as
above.
The arrangements for these several adjustments are as follows:-
1st. I cut a screw on the top pulley shaft C on either side of the after bearing F,
and I provide two sets of lock nuts G at either end of the bearing. By turning
these two sets of lock nuts in either direction it is easy to make the required
adjustment and give the upper pulley the desired overhang as regards the lower
wheel.
2nd. For the second adjustment I mount the two bearings F F carrying_the
upper pulley shaft C in slides H which can be moved transversely by screws J on
planed faces on the bracket which carries the wheel.
3rd. In order to give the vertical tilting motion to the top saw pulley, I mount
the slide H carrying the after bearing F on a cylinder K sliding vertically in a
socket L and provided with a screw M turned by the hand wheel N by which the
said bearing can be readily raised or lowered.
4th. The horizontal swivelling motion of the top saw pulley A is accomplished
by fitting the slide H which carries the after bearing F of the pulley shaft C with
a screw nut in which works a screw bearing at one end a bevil wheel O gearing
with a bevil wheel O' upon a spindle P worked by a hand wheel Q so that the
after slide can be traversed independently of the fore one.
The two bearings F F of the upper saw pulley shaft C are so socketed in their
plummer blocks that they can swivel in any direction to compensate for the varying
angles of the shaft as above described.
In order to obtain the proper tension on the saw blade my improved arrangement
is as follows :—
The upper saw pulley A with its shaft C and bearings F F is carried on a
vertical sliding bracket R, the weight of which is supported on a strong vertical

page_text: screw S which may be run up and down by means of the ratchet nut S¹ and its
lever S working between two lugs S³ on the frame. The screw S works up and
down through a nut T to suit saws of different lengths. This out T is formed with
two lugs or projections T₁ one on either side, which rest upon two levers U pivotted
on a pin V immediately behind the same, the levers U being so formed that the
horizontal centre line of the lever passes through the pins V and also through the
point of contact of the levers with the lugs on the nut T in order to minimise
friction.
The outer ends of these levers U are connected by means of four links W and a
cross-piece X to another lever Y behind the machine and at right angles to the
levers last mentioned, the whole forming a system of compound levers of great
power and one which allows of the sliding weight Z being conveniently placed and
readily adjusted.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The several means substantially as described for adjusting the upper wheel.
2. The means for obtaining proper tension on the saw blade substantially as
described.
3. The combined band sawing machine substantially as described and shown in
the drawings.