Improvements in Saws and Machinery for Sawing Stone and the like.
Year: 1887

page_text: Improvements in Saws and Machinery for Sawing Stone and the like.
I, JAMES PECKOVER of No. 3310 Woodland Avenue in the City of Philadelphia'
Pennsylvania United States of America Stone Mason 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 consists of certain improvements in the construction of saws and
machines for sawing all kinds of stones or the like. The main objects of my invention
are to simplify the construction of the mechanism for operating the saws and also to
construct the saw itself as economically as possible yet so that it shall be strong and
not liable to get out of order that it shall be thoroughly effective in action by
permitting the sand or other cutting granular material to pass to the bottom of the
saw kerf and so that the minimum of amount of power shall be required to drive the
saw or gang of saws.
In the accompanying drawings Figure 1 is a side view of a stone-sawing machine
provided with my improvements. Figure 2. is a plan view. Figure 3 is an end view.
Figure 4 is a perspective view illustrating the form of blank from which I prefer to
cut my improved saw.
Figure 5 is a perspective view of sufficient of the saw to illustrate my Invention.
Figure 6 is a view drawn to a larger scale and illustrating the action of the saw, and
Figure 7 is a view of a modification.
The main frame A of the machine, together with the saw frame G and carriage-bed B,
on which the saw frame reciprocates, may be of any suitable construction.
The carriage-bed is suspended by means of cords or chains e, to which are connected
the counter-weights E; but in the present instance, instead of connecting the cords or
chains directly to the carriage-bed, I prefer to use the links and swivels f (illustrated
in figure 1,) so that the tension of the ropes or chains can be readily adjusted
thereby. The two ropes or chains on each side pass over a flanged pulley P.
As the most convenient way of securing the ropes or chains to the pulleys, so as to
insure the uniform elevation of the saw-carriage, I thread the ropes or chains through
openings in the rims of the pulleys as illustrated more clearly in Figure 3.

page_text: These pulleys are arranged in such a position that one of the ropes on each side can
pass down vertically from the pulley to its connection with the carriage-bed, while the
other rope or chain passes over a small guide pulley, r, near the other end of the
machine before passing to its connection with the carriage-bed.
If preferred, the carriage-bed may be dispensed with and the chains or ropes be
connected by means of the link and swivels directly to the saw-frame, as will be
readily understood; but I prefer the use of the carriage-bed, as in that way a linear
reciprocating motion is obtained for the saw and a better cutting effect is secured
than is the case when the ropes or chains are connected directly to the saw-frame
which would then have a pendulum motion. To impart the reciprocating motion to
the saw-frame, I provide at the end of the frame of the machine a vertical
crank-shaft F, with a long crank-wrist, fconnected to the saw frame G by a connecting
rod, g. The stub end of the connecting-rod will move longitudinally on the long wrist
as the saw frame descends in cutting the stone S.
A driving pulley, K, is provided on the crank shaft, and I prefer also, to provide the
latter with one or more fly-wheels, d.
The sand-feeding device I prefer to employ consists of a hopper provided with a
number of discharge spouts each fitted in the interior with a fluted cone and having
connected thereto a telescopic depending tube or trough for conducting the sand over
the saw blades and in connection with these sand-feeding devices I prefer to use a
water supply, consisting of a main transverse pipe, L, and longitudinal distributing
pipes l.
These distributing pipes are provided at intervals with outlets having sinall
controlling-cocks and in order to get an even distribution of the water I run from
the nozzle of each cock a cord or wire, m down to each sand tube or conduit n, so
that the water can mix with the sand as it is delivered from the conduits to facilitate the
passage of the sand to the bottom of the saw kerf.
The saw itself I construct with projecting teeth in one piece with the saw blade and
of greater thickness than the blade-Saws for sawing stone have been heretofore
made with projecting teeth thicker than the blade, but in that case the teeth were
separate inserted teeth and the saws were consequently expensive to make and the
teeth were liable to come out of place.
I obviate these objections by making the projecting thickened teeth in one piece with
the blade.
In practice the saws are made preferably by first rolling an iron blank of the form
illustrated in Figure 4 that is with a central portion D¹, somewhat thicker than the
edges D, D.
Then by suitable means I cut this blank so as to produce therefrom two saws of the
form illustrated in Figure 5, the thickened portion A of the blank forming the
projecting teeth of two saws. The metal cut from between the teeth of one saw forms
the teeth of the other saw, while the thinner edges D D of the blank form the blades of
the two saws.
By preference I make the adjacent edges of the teeth of each saw parallel as shewn
in Figure 5 but this is not essential, as in some cases the teeth may be of the tapering
form illustrated in figure 7.
The cutting edges of the teeth may with either form of tooth be slightly rounded,
as indicated by dotted lines in Figure 7 but this I do not regard as necessary, as the
teeth will naturally become worn to this shape when put into use.
A saw of the construction described possesses the advantages not only of strength
and economy of construction, but it also permits the sand or other granular material,
which is fed to the saw, to pass directly to the bottom of the saw kerf. This will be
readily understood on reference to Figure 6, which shows in sections the saw
in position in the kerf. A supply of sand can thus be continuously kept in
effective action at the bottom of the saw kerf, under the saw teeth without any
tendency to wedge the saw in the kerf, as would be the case if the blades were made
simply tapering upward from a widened cutting edge. The friction commonly
experienced between the blade of the saw and the walls of the kerf is by this construction

page_text: greatly reduced, and consequently the power necessary to drive a saw or gang of
saws of the construction described is much less than would be required if the blade
were of the same thickness as the teeth.
The teeth are made of substantially uniform thickness throughout in order that
they may wear as long as possible and in order that there may be the least possible
tendency for the sand to wedge in between the sides of the teeth and the walls of
the kerf.
Having now described and particularly ascertained the nature of my said Invention
and in what manner the same is to be performed I declare that what I claim is ;
First: A saw for sawing stone or the like the said saw having projecting teeth
formed in one piece with the blade, the said teeth being thicker than the blade,
substantially as and for the purpose hereinbefore set forth.
Second: The combination with the frame of a machine for sawing stone or the like
of a vertical crank-shaft having a long crank-wrist connected with the saw-frame by a
rod or connection longitudinally moveable on the said crank-wrist substantially as
hereinbefore set forth.
Third: The combination with the main frame of a machine for sawing stone or the
like and the saw frame, of suspending ropes or chains, counterweights therefor, and
pulleys over which the ropes or chains pass and through which they are threaded
substantially as hereinbefore described.
Fourth: The combination with the sand-feeding devices of a machine for sawing
stone or the like of water pipes having a number of outlets, and cords or wires running
from the said outlets to the sand feeding conduits, as and for the purpose hereinbefore
described.