Improvements in Machines for Sawing Cold Metal and Stone.
Year: 1899

page_text: Date of Application, 4th Apr., 1899
Complete Specification Left, 4th Jan., 1900-Accepted, 4th Apr., 1900
PROVISIONAL SPECIFICATION.
Improvements in Machines for Sawing Cold Metal and Stone.
I, JOSEPH HAMILTON, of 21, Drakefield Road, Upper Tooting, in the County of
London, Engineer, do hereby declare the nature of this invention to be as
follows:-
In bearings upon a bed plate or framing I mount either vertically or hori-
zontally the trunnions at the end of a rectangular frame upon the end above the
trunnions are two bearings parallel to the two trunnions, into which a shaft is
fitted to one end is keyed a pulley outside which may be fitted another pulley
to run loose. Between the two bearings and upon the shaft is keyed a worm
to gear into a worm wheel keyed to a projecting end of a shaft at right angles
(horizontally) to the worm shaft. The horizontal shaft is carried in bearings
in the frame, between the bearings against the front end bearing, upon the shaft
a worm is fitted, and against the worm end is placed a strong spiral spring and
upon a screwed portion of the shaft a nut is fitted to allow of the spiral spring
being compressed against the end of the worm. Or I may use a cranked L lever
the short end to Dear against the worm's end, the long end can be weighted to
give more or less pressure against the worm. The lever has it fulcrum pin
attached to the frame, and the worm is free to slide along the shaft, but not
to turn round it-under the worm is a segment of a clutch worm wheel, or it
may be a complete wheel, carried upon a shaft held in bearings on the underside
of the frame, next the worm wheel is a clutch to gear into the worm wheel
clutch, on the end furthest from the clutch the shaft is fitted with a spur pinion
which gears into a spur segment attached to the bed. The outer end of the
shaft is fitted either with a grooved or fat pulley with a chain, rope, or band
partly round it, to the free end of the chain weights are attached.
Instead of the pulleys I may use a vee grooved wheel, and fit the groove with
a vee cam or I may use a flat face wheel and flat face cam hinged at required
distance to a lever which may be weighted as required. I make the shaft the
fulcrum for the lever. A ratchet wheel with ratchet, lever and weight will
also effect the required purpose.
Upon the end of the horizontal shaft at the free end of the frame (which I
may term the swing frame) a mitre or bevel wheel is keyed and gears into a
similar wheel on another cross shaft carried in bearings on the swing frame end.
The shaft may be fitted with a suitable saw at one or both ends.
The manner in which the work is performed is as follows.
The pulley upon the shaft end above the trunnions when rotated transmits
motion from the worm on the same shaft to the worm wheel into which it gears
and thence by shaft and gearing to the saw shaft.
Should the feed be too great for the saw to do its work properly
at times through the varying degrees of hardness of material the spiral
spring will compress and the saw will
be relieved for a portion
of a revolution. And if the weight on the chain, or levers, are
adjusted to be in excess of the weight of the free end of the frame when the

page_text: clutch is thrown out of gear with the worm wheel, the free end will rise above
the material and take the saw also clear of it. If at times the spring on the
shaft against the worm will not give sufficient relief or reduction of feed the
weight on the chain or on the levers, will allow the saw to adjust itself to required
rate of feed, and allow saws of considerable eccentricity to work as though they
were quite true. For sawing cold metal I prefer to use the ordinary plate saw.
For stone I substitute saws with loose teeth when the hardness is about equal to
Portland stone.
I, JOSEPH HAMILTON, late of 21, Drakefield Road, Upper Tooting, in the
County of London, Engineer, at present residing at 113, Victoria Road, Old
Charlton, Kent, 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:-
In bearings upon a bed plate or framing a, I mount vertically or horizontally
the two trunnions H H on the end of a rectangular frame b, upon the same end
above the trunnions H H' are two bearings FF parallel to the trunnions into
which I fit a shatt yy one of the trunnions projects through its bearing and
carries a spur wheel with a pulley attached to run loose upon it outside
the pulley I place another pulleys also to run loose. On the end of the
spindle (which is above the trunnions which projects through its bearing I key
a spur wheel jj to gear into the spur wheel kk below it, upon the spindle
which has the spur wheel jj keyed to it-between the spindle bearings. I fit
a worm to gear into a worm wheel hh which is keyed to the end of a shaft
at right angles under the worm shaft yy'. The horizontal shaft ww¹ to which
the worm wheel hh¹ is keyed is carried in bearings II above the trunnions of
the hinged frame are bearings FF for the shaft yy. Between the bearings II'
against the front end bearing upon the shaft I fit a worm m m¹
and against the end of the Worm m, mi I place a strong spiral
spring n,, and
upon a screwed portion of the shaft against the
spring I fit a nut to allow of the spring n¹ being compressed against the
end of the worm, or I may use a cranked L lever the short end to bear against
the end of the worm. The long end can be weighted to give more or less
pressure against the end of the worm. The lever to have its fulcrum pin attached
to the frame a.
The worm m, m' is free to slide on the shaft but not to turn round the
shaft.
Underneath the worm m m¹ is a segment of a worm wheel, or it may be a
whole worm wheel d d¹ carried by a shaft in bearings formed in the brackets ccl
on underside of the frame bb into which the worm m m¹ gears, upon the worm-
wheel boss there is one part of a cone friction (or other friction clutch part as
in general use) and upon the same shaft is fitted the other part of such friction
clutch which can be put into gear with the part on the worm wheel boss.
The worm wheel dd' can revolve upon the shaft. To the end of the spindle
or shaft nearest the saw is keyed a spur pinion ff¹ to gear into a segment

page_text: rack g g fixed to the bed plate a, to the other or outer end of the spindle is keyed.
a grooved, or flat faced pulley, or wheel eel with chain, band, or rope Q, fixed
to it and partly round it. To the free end of the chain, band, or rope, a weight
or weights PP may be attached.
Instead of the pulley I may use a vee grooved wheel with a vee cam to fit into
the vee groove in the wheel, or a flat faced pulley with a flat cam hinged at a
requisite distance to a lever which can be weighted as may be required. I make
the shaft the fulcrum (for the lever) a ratchet wheel with ratchet and lever and
weights will also effect the required purpose.
The friction clutch is arranged to slip due to the resistance imparted to the
saw's periphery by the material it is operating upon. The clutch uu is arranged
to give only a certain amount of power, and that which may be required for
the various amounts of work to be executed. If say a 12in. x 12in. solid bar of
steel has to be sawn the friction clutch will have to be set at a greater driving
power than for Gin. × 6in. and so less in proportion to lesser sections to be
sawn. The same rule will apply to sawing stone. Upon the end of the horizontal
shaft ww at the free end of the swing frame (which I may term the swing
frame) a mitre or bevel wheel 2 is keyed which gears into a similar wheel gly
on another cross shaft AA carried in bearings LL¹ on the ends of the swing
frame b¹. The manner in which the work is performed is as follows. The
spur wheel with pulley attached, which is mounted upon the trunnion
end of the frame when rotated imparts motion to the spur wheel jj which
is keyed to the shaft y y¹ and transmits motion through the worm it on the same
shaft (between the bearings) to the worm wheel h h¹ upon the end of the horizontal
shaft and thence to the saw shaft A A' and the various other moving parts
attached to the swing frame b (I do not confine myself to the use of worm
gearing for the second motion, I may use mitre or spur gearing).
If the feed should be found to be too great for the saw to do its work properly
at times on account of varying degrees of hardness of material the spiral spring
nu will compress and the saw will be relieved for part of a revolution. If the
weights PP on the chain Q (or levers) are adjusted to be in excess of the
weight of the free end of the frame b₁ it will rise above the material and take
saw 0, also clear of it. If at any time the spiral spring n, n', on the horizontal
shaft (, ) pressing against the worm mm will not give sufficient relief or
reduction of feed the weight P P on the chain Q, will allow the saw O to adjust
itself to required feed and allow saws of considerable eccentricity to work as
though they were perfectly true.
To illustrate more fully the manner in which the feed is performed, is as
follows, during the working of the saw O and the friction clutch u is in gear the
saw will descend and operate upon the material, but if the material requires more
power for sawing than the friction of the clutch w, is set to impart, the clutch u,
will slip and the saw will only do the amount of sawing equal in amount due
to the power given off by the clutch up to the slipping extent, and the weight
on the end of the chain Q being arranged in excess of the weight of the free
end of the frame b, there will come into action the holding back of the feed
due to the extent of the excess of the weight to lift the free end of the swing
frame and its various parts. Probably after the saw has made a few
revolutions during the compression of the spiral spring n on the shaft ww
it will have been so far eased that the spring will resume its normal position,
should it not so occur, further relief will be given by the slipping of the clutch, u,
which is set to be very little in excess of the power of the spiral spring n and the
holding back power due to the weight P on chain Q. By this arrangement the
first driving power may be enormously in excess of the power that would injure
the saw or saws, and gear of the machine.
For sawing cold metals I prefer to use the ordinary plate saw. But for stone
I substitute saws as shown by Fig. 3. with loose teeth when the hardness is about
equal to Portland stone.

page_text: DESCRIPTION OF DRAWINGS.
Fig. 1. Is a side elevation of the machine.
Fig. 2. Is a plan of the machine.
Fig. 3. Is an elevation of saw for stone..
The corresponding letters with their figures refer to corresponding parts of the
machine on Figs. 1 and 2, a al is the bed plate, the swing frame-c c¹
brackets with bearings on underside of swing frame-dd worm wheel under
horizontal shaft-e el grooved wheel-f f¹ pinion gearing into rack (g g¹)
―h h¹ worm wheel on the end of horizontal shaft (ww)- ¿
on shaft (y)-jj spur wheel on shaft (y y)-k k¹ spur
on
worm
wheel
trunnion driving pulley-mm sliding worm on shaft (1)
nn spiral spring-0, 02, 03, circular saw for metal-P P weight on
chain (Q) mitre wheels--ss is a loose pulley-tt clutch fork rod,
with clutch fork-uu¹ friction clutch-clutch rod handle-ww horizontal
shaft is the trunnion end-yy shaft above the trunnions-z z¹ nut on
shaft (ww) A A¹ is the saw shaft B dotted lines through which saw descends
and ascends F F¹ bearings of shaft (y y¹)-H H¹ the frame trunnions-D E Fig. 1
metal to be sawn.
-x
Having thus described and ascertained the nature of my invention and in
what manner the same is, or may be, performed I would have it understood
that I claim -
The mounting and balancing of a framing capable of sustaining and carrying
its various working parts to impart motion therefrom to a circular saw, or saws
for sawing cold metal and stone. The spiral spring, the frictional clutch, and
the balancing arrangement substantially as described herein.
Dated this 3rd day of January 1900
J. HAMILTON.