Improvements in Band Sawing Machines and in Carriages therefor.
Year: 1893

page_text: Date of Application, 18th Mar., 1893
Complete Specification Left, 18th Dec., 1893-Accepted, 27th Jan., 1894
PROVISIONAL SPECIFICATION.
Improvements in Band Sawing Machines and in Carriages therefor.
We, JOE SAGAR, and DONALD SAGAR, of Canal Works, Halifax in the County
of York, Saw Mill Engineers, do hereby declare the nature of this invention to be
as follows:-
:-
This invention has reference to band sawing machines and in carriages employed
therein. Our improvements in band sawing machinery consist firstly, in means to
be employed for automatically maintaining an equal tension or strain upon the
band saw as it expands and contracts which takes place when the saw is at work.
To accomplish this, we arrange that the several levers and rods are all provided
with knife centres in contradistinction to shafts as hitherto. According to our
invention the axle which carries the top pulley over which the band saw passes, is
borne by two pillars the bottom of which pillars rest upon V or rounded centres
projecting from the top of a vertical screw shaft which can be raised and lowered
for tightening or slackening the band saw by means of a hand wheel operating
worms and wheels. The bottom of the screwed rod rests upon a case hardened
piece of steel carried by a horizontal lever connected by bell-crank form of
connecting rods or links to a weighted rod. By employing knife centres for the
bearings of the several levers and rods a very sensitive arrangement for adjusting
the tension of the band saw is provided.
Provision is also made for canting or tipping the top pulley over which the saw
passes, so as to adjust itself to the band saw and to make it nip or bite more keenly
around the periphery of the said pulley, and this canting of the pulley is effected
by a vertical screw which bears one of the screws previously mentioned, such
second named screw being raised and lowered by another hand wheel which
operates another worm and wheel at the foot of the second named screw. Provision
" cross
is also made for giving to the axle which carries the top band pulley a
line or transverse movement for moving the shaft out of parallel with the bottom
"
shaft.
Our invention in the carriages of band saws has reference to the knees or fences
which keep the log up to the saw. Hitherto these knees or fences (of which there
are several according to the size of machine) have been moved against the log
simultaneously and this has been effected by means of screws and bevil wheels
operated by ratchet wheels and pulleys set into motion by a band lever, but we
propose to provide means whereby each knee or fence may be moved separately or
independently of each other so as to be adapted to logs having a wavy or irregular
surface. To do this the bevil wheels upon the operating screw have internal screw
threads formed in them and carried by brackets suitably placed. These nutted
bevil wheels are in gear with other bevil wheels on the vertical axle of which is a
swaife. When the whole series of knees require to be moved simultaneously the
swaifes are made stationary by a pin, but when one of the knees requires moving
separately the pin is removed and the swaife operated in such a manner as to cause
the nutted bevil wheel to be moved on the screw whilst the screw is stationary ;
by this means each knee can be set up to suit the requirements of a log of irregular
shape.
Our further invention in carriages consists in "setting off" the log from the saw
as the carriage is backing for the purpose of making another cut.
For carrying out this part of our invention we form underneath the carriage an
inclined groove fitting onto a cam or projection formed on the top of a crank or a

page_text: series of cranks placed loosely on the axle of the wheels carrying the carriage.
This crank or cranks is prevented from moving laterally on the shaft by a collar
at each side of the crank and by an arrangement of levers and compound rods the
workman by moving a hand lever can rock the cam, crank, or cranks, in doing
which, they act in the inclined groove in such a manner as to cause the carriage to
recede from the saw, so that on the carriage backing the log does not rub against
the saw; on the operative moving the hand lever in the opposite direction the
levers and rods bring the carriage and the log into proper relation with the saw.
Dated this 17th day of March 1893.
TASKER & CROSSLEY,
Halifax, Agents.
•
COMPLETE SPECIFICATION.
Improvements in Band Sawing Machines and in Carriages therefor.
We, JOE SAGAR, and DONALD SAGAR, of Canal Works Halifax, in the
County of York, Saw Mill Engineers, 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 has reference to band sawing machines and in carriages employed
therein. Our improvements in band sawing machinery consist firstly, in means to
be employed for automatically maintaining an equal tension or strain upon the band
saw as it expands and contracts which takes place when the saw is at work. To
accomplish this, we arrange that the several levers and rods are all provided with
knife centres in contradistinction to shafts as hitherto.
In order that this part of our invention may be clearly understood we will make
reference to the accompanying sheets of drawings illustrative thereof, wherein
Fig. 1 is end elevation of such parts of a band sawing machine as is necessary
to illustrate our improvements, Fig. 2 is side elevation of same, partly in section,
and Fig. 3 a plan view thereof also partly in section.
A represents the bottom axle, and B the top axle, both of which carry pulleys C
upon which the band saw is mounted and by which it is driven. The top axle B is
mounted upon and borne by two pillars D, the bottom of which pillars rest upon
V or rounded centres projecting from the top of the vertical screw shafts E, F,
both of which can be raised and lowered simultaneously (for the purpose of
tightening or slackening the band saw) by means of a hand wheel G operating
worms H mounted on shaft H' in gear with worm wheels I fixed to the bottom of
the vertical screw shafts E, F. The pillars D are guided and kept in a perfectly
vertical position by a bush on the top of the hollow pillars D' and also by a ring
plate D both of which are bored out true to receive the pillar. These pillars
whilst they are raised by the screws E, F, in their upward movement which is at
all times very little, the said pillars descend by their own weight on the screws E, F,
being lowered. The bottom of the screw shaft E rests upon a case hardened piece
of steel J carried by a horizontal lever K connected by bell crank form of
connecting rods or links L to a vertical rod M weighted at N.
It will be observed that the several studs a, b, c, and d, are all A or what are
called knife centres after the manner of scale beams as are also the bottom of the
two pillars D by which means the several levers and rods are very sensitive
consequently the tension of the band saw can be adjusted to the greatest nicety.
Provision is also made for canting or tipping the top driving pulley over which
the band saw passes so that the periphery of the said pulley can be adjusted to bite
or nip the saw more keenly, and this canting of the top pulley is effected by the
vertical screw O which bears or supports the vertical screw F, such screw O being
raised and lowered by hand wheel P which operates a worm on a short cross

page_text: shaft S gearing with a worm wheel T at the foot of the said screw O see detail
Fig. 4.
It will thus be seen that whilst the hand wheel G together with its
accompanying worms and wheels are employed to adjust the position of the top
axle, that the said axle can in addition be cantered or tipped by the use of the
small hand wheel P. Secondly. Our invention in the carriages of wood sawing
machines has reference to the knees or fences which keep the log up to the saw.
Hitherto these knees or fences (of which there are several according to the size of
machine) have been moved against the log simultaneously, and this has been effected
by means of screws and bevel wheels operated by ratchet wheels and pulleys set
into motion by a lever, but we propose to provide means whereby each knee or
fence may be moved separately or independently of each other so as to be adapted
to logs having a wavy or irregular surface.
This part of our invention is shewn at Fig. 5 which is sectional end elevation of
the carriage of a wood sawing machine, Fig. 6 front elevation, Fig. 7 plan view of
same, and Fig. 8 is an end view of Fig. 6. A represents the end of a log of wood
resting upon a gauntry B. Upon this gauntry B there are mounted fences or
knees C capable of being slided backwards and forwards on the said gauntry for
adjusting the log in relation to the saw.
In carrying out our invention the bevel wheels D working upon the screw E
have internal screw threads formed in them, the said bevel wheels being supported
by brackets F. These nutted bevel wheels D are in gear with other bevel wheels G
on the vertical axle of which is a handle or swaife H. When the whole series of
knees or fences C require to be moved simultaneously, the swaifes H are each made
stationary by a pin I, but when one of the knees C requires moving separately the
pin I is removed and the swaife operated in such a manner as to cause a nutted
bevel wheel D to revolve and so move one of the knees to or from the log whilst
the said screw remains stationary. By this means each knee can be set up to suit
the requirements of a log of irregular shape. When however all the knees require
moving together, the longitudinal shaft J is operated by the lever J in the ordinary
manner, the rotary motion of the said shaft J causing the bevel wheels K to operate
a corresponding bevel wheel L fixed on the end of each screw shaft E one for each
knee C.
Our further improvements in wood sawing machine carriages consist in setting
off the log from the saw when the carriage is backing to make another cut. For
carrying out this part of our invention we form underneath the carriage an inclined
groove M shewn more clearly in the plan view Fig. 7. Within each groove is a
cam or projection N formed on the top of a crank or a series of cranks O placed
loosely on the axle P which carry the carriage wheels R. Each crank O is pre-
vented from moving laterally upon the shaft P by collars a, b, placed on each side
of the said crank. To the top and bottom of the cranks O are connecting rods S
attached to the bottom of the vertical lever arm T so that when the workman
operates the said lever in one direction the cranks O are oscillated in doing which
their upper portion N rides in the inclined groove M and as the said cranks have
no lateral movement the carriage is (through the inclined groove) made to recede
from the saw so that on the carriage backing the log will not rub against the saw;
but on the operative moving the hand lever T in the opposite direction the rods S
and cranks will bring the carriage and the log back into proper relation with
the saw.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is:-
:-
Firstly. In band sawing machines, the use therein of knife centres employed in
the manner substantially as herein shewn and described.
Secondly. In band sawing machines, the arrangement of levers and rods in com-
bination with worms and wheels for adjusting the tension of the band saw as herein
shewn and described.

page_text: Thirdly. In band saws, the means substantially as herein shewn and described
for canting or tipping the top driving wheel.
Fourthly. In carriages of wood sawing machinery, the use of the nutted bevels
wheels D plain bevel wheels G swaife H and pin I for operating each fence or
knee separately and individually in the manner shewn and described in the
drawings.
Fifthly. In carriages of wood sawing machinery, the combination therewith of
the cam grooves M and operating cranks O employed for setting off the log from
the saw substantially as shewn and described herein.
Dated this 16th day of December 1893.
TASKER & CROSSLEY,
Halifax, Agents.