IMPROVEMENTS IN MACHINES FOR FRET CUTTING OR SAWING
Year: 1865

page_text: LETTERS PATENT to William Middleton, of Ennismore Mews, Knights-
bridge, in the County of Middlesex, Engineer, for the Invention
of "IMPROVEMENTS IN MACHINES FOR FRET CUTTING OR SAWING."
Sealed the 8th May 1866, and dated the 10th November 1865.
PROVISIONAL SPECIFICATION left by the said William Middleton at the
Office of the Commissioners of Patents, with his Petition, on the
10th November 1865.
I, WILLIAM MIDDLETON, of Ennismore Mews, Knightsbridge, in the
County of Middlesex, Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN MACHINES FOR FRET CUTTING OR SAWING," to
be as follows:
In constructing fret sawing machines I mount and stretch the saw
between the limbs of a U-shaped frame made of a bar of wrought iron or
steel on edge, and having sufficient strength to take the strain of the saw
and at the same time possessing considerable spring, which permits of
the tension of the saw being easily regulated. I dispose the limbs of the
U frame in a horizontal position, and mount it on a fixed fulcrum at the
bend, that is to say, at a point of extreme distance from the ends of the
limbs. The upper limb is disposed above the table of the machine, while
the lower one is below it. The saw frame oscillating up and down on a

page_text: fixed fulcrum, the saw in its motion necessarily describes a segment of a
circle, which to a certain extent is prejudicial to its action; to counteract
and cause it to move constantly in the same right line at the cutting point
I fix a guide in the table on which the work rests, this guide embraces the
back of the saw and so controls and keeps it always in the position desired.
The table is mounted on a suitable framework, and the saw frame driven by
a treadle from below by a connecting rod directly from the treadle to the
lower limb of the saw frame; I also connect the treadle by a second rod
with a crank on a fly wheel axis to regulate and maintain the motion; I
further apply a presser above the work being operated on to keep it
down on the table while being cut. The saw is mounted and stretched
between the limbs of the frame by screws and nuts and otherwise much
in the usual manner.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Middleton in the Great Seal Patent Office on
the 10th May 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
MIDDLETON, of Ennismore Mews, Knightsbridge, in the County of
Middlesex, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of November, in the year of our
Lord One thousand eight hundred and sixty-five, in the twenty-ninth year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Middleton, Her special licence that I, the said William
Middleton, my executors, administrators, and assigns, or such others as I,
the said William Middleton, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN MACHINES FOR FRET CUTTING OR SAWING," upon the
condition (amongst others) that I, the said William Middleton, my execu-
tors or administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent Office

page_text: within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said William Middleton, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, reference being had to the Sheet of Drawings here-
unto annexed, and to the letters and figures marked thereon (that is to.
say):-
In constructing fret sawing machines I mount and stretch the saw
between the limbs of a U-shaped frame made of a bar of wrought iron or
steel having sufficient strength to take the strain, and also possessing con-
siderable spring or elasticity, which permits of the tension of the saw being
easily regulated. I dispose the U frame in a horizontal position and
mount it on a fixed fulcrum at the bend, that is to say, at a point of
extreme distance from the ends of the limbs. The upper limb is disposed
above the table of the machine, while the lower one is below it. The saw
frame oscillating up and down on a fixed fulcrum, the saw in its motion
necessarily describes a segment of a circle, which to a certain extent is
prejudicial to its action; to counteract this and cause it to move constantly
in the same right line at the cutting point I fit a guide in the table on
which the work rests, which guide embraces the back of the saw and so
controls it and keeps it in the position desired. The table is mounted on
For this
a suitable framework and the saw frame driven by a treadle.
purpose I connect the treadle from below by a rod directly to the lower
limb of the saw frame, and I also connect the treadle by a second rod with
a crank on a fly wheel axis to regulate and maintain the motion. I further
apply a presser above the work being operated on to keep it down on the
table while being cut, if necessary. The saw is mounted and stretched
between the limbs of the frame by screws and nuts much in the usual
manner of stretching saws between two points.
DESCRIPTION OF DRAWINGS.
Figure 1 represents a perspective view of the machine complete;
Figure 2, a vertical section of the same on an enlarged scale; while Figures
3, 4, 5, 6, and 7 represent some of the parts detached in different positions,
a, a, is the frame in which the saw is fixed and stretched, it consists of a
bent piece of iron increasing in strength towards the back part b, at which
point it is mounted on a fulcrum fixed to the table c of the machine.
Table c is mounted and fixed on standards d, d, which standards carry at

page_text: foot a treadle e oscillating on a fulcrum at f, by which the machine is driven.
From the treadle e there are two connecting rods, one g which connects
the treadle direct with the lower limb of the frame a, while the other h
communicates between the treadle and the crank pin fixed on the fly wheel
i, which is mounted on a stud fixed in one of the standards d. Thus it
will be seen that no motion passes through the fly wheel to the saw frame,
the power and motion being transmitted directly from the treadle è by rod
g to the saw frame, while the fly wheel at same time being connected
as described equalizes the motion of the whole; k is a guide, seen separately
at Figures 8 and 9, fixed under the table ċ to steady the lower limb of the
saw frame. The frame a, a, as before mentioned, I make of iron of con-
siderable strength at the doubled part and tapering towards the ends, I
bend the metal on edge, and so forming each limb of the frame of greater
depth than thickness, whereby a light yet stiff and elastic saw frame is
produced. The saw is fixed in the frame a by jaws clipped together by
thumbscrews n, n, and the saw placed in tension by thumbscrew p, all as
in the ordinary method of stretching reciprocating fret. saws. Motion
being given to the frame a by the treadle as described, imparts a recipro-
cating motion to the saw 1, but which by reason of the frame being
pivotted at b would, if not otherwise controlled, move in the arc of a circle ;
to obviate this I dispose a metal socket piece r, seén separately in plan at
Figure 3, in side elevation at Figure 4, in horizontal section at Figure 5,
and in vertical section at Figure 6. In this socket piece ŕ I dispose ä
small hardened steel roller t, seen separately at Figure 7, having a groove
turned in it against which the back of the saw bears throughout the
extent of its motion. By the saw bearing against the roller t just below
the cutting point, the saw is constrained to move always in the same linė
of motion at the cutting point, instead of participating in the circular
motion of the frame as described, from the fulcrum 6 causing it to cut
equally throughout its whole motion, and as if moving between parallel
guides. If a work presser is used it consists simply of an arm fixed at the
back end of the table, as seen dotted in Figure 1, and furnished with a
'roller or rollers to bear on the wood or other material being cut.
Having described the nature of my Invention, and the manner of per-
forming the same, I declare that what I claim as my Invention to be
protected by the herein-before in part récited Letters Patent is,-
First, the application of the guide r, t, or any mère mechanical equi-
valent therefor, in the table for guiding and sustaining the saw of a fret
cutting or sawing machine as herein-before described.

page_text: Secondly, the arrangement and connection of the treadle with the saw
frame and with the fly wheel, as and for the purpose herein-before
described.
In witness whereof, I, the said William Middleton, have hereunto
set my hand and seal, this Ninth day of May, in the year of
our Lord One thousand eight hundred and sixty-six.
Witness,
W. CLARK,
Patent Agent,
53, Chancery Lane,
London.
W. MIDDLETON. (L.S.)