IMPROVEMENTS IN SAWS."
Year: 1869

page_text: LETTERS PATENT to Bristow Hunt, of No. 1, Serle Street, Lincoln's
Inn, in the County of Middlesex, Gentleman, for the Invention
of "IMPROVEMENTS IN SAWS."-A communication from abroad by
Gottlieb Maulick, Thomas Preston Marshall, and George Whitfield
T
PROVISIONAL SPECIFICATION left by the said Bristow Hunt at the
Office of the Commissioners of Patents, with his Petition, on the
15th February 1869.
I, BRISTOW HUNT, of No. 1, Serle Street, Lincoln's Inn, in the
County of Middlesex, Gentleman, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN SAWS," (a communication to me
from abroad by Gottlieb Maulick, Thomas Preston Marshall, and George
Whitfield Rowley, all of Trenton, New Jersey, United States of America,)
to be as follows:-
The first part of this Invention consists of a detachable saw tooth
fitted to a recess in the blade, and retained therein by a spring catch, so

page_text: that the tooth may be easily removed and replaced and retained in its.
place without the aid of rivetting appliances, which tend to distort
the blade.
The second part of the Invention consists of a planing attachment for
circular and other saws, the said attachment being either a part of a t
detachable tooth or being on a separate plate attached to the blade, the
object of this part of the Invention being to render the usual rough
surface of boards cut by saws smooth and even.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Bristow Hunt in the Great Seal Patent Office
on the 5th August 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BRISTOW
HUNT, of No. 1, Serle Street, Lincoln's Inn, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of February, in the
year of our Lord One thousand eight hundred and sixty-nine, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Bristow Hunt, Her special
licence that I, the said Bristow Hunt, my executors, administrators,
and assigns, or such others as I, the said Bristow Hunt, my exe-
cutors, 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 SAWS," (a communication to me from abroad by Gottlieb Maulick,
Thomas Preston Marshall, and George Whitfield Rowley, all of Trenton,
New Jersey, United States of America) upon the condition (amongst
others) that I, the said Bristow Hunt, my executors 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 within six

page_text: calendar months. next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Bristow Hunt, do hereby declare
the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement in writing, and on reference being had to the
accompanying Sheet of Drawings, that is to say :-
The first part of this Invention consists of a detachable saw tooth
fitted to a recess in the blade, and retained therein by a spring catch, so
that the tooth may be easily removed and replaced and retained in its
place without the aid of rivetting appliances, which tend to distort
the blade..
The second part of the Invention consists of a planing attachment for
circular and other saws, the said attachment being either part of a
detachable tooth or being on a separate plate attached to the blade, the
object of this part of the Invention being to render the usual rough
surface of boards cut by saws smooth and even.
Such being the nature and object of the said Invention for
"Improvements in Saws," I will now proceed to describe more in detail
the manner in which the same is to be or may be performed or carried
into practical effect; and in order that the same may distinctly
understood I have annexed hereunto a Sheet of Drawings illustrative
thereof, and have marked the same with Figures and letters of reference
corresponding with those in the following thereof, that is to say :-
Figures 1, 2, and 3 are side views of part of a saw blade with
detachable teeth and illustrate the first part of the Invention; Figure 4,
a side view of part of a saw blade with planing device on detachable
teeth; Figure 5, a section on the line 1, 2, Figure 4; Figure 6, a part of
saw blade with planers separate from the teeth; Figure 7, a section on
the line 8, 4, Figure 6; Figures 8 and 9, sections showing the manner of
introducing the planers into the blade; and Figure 10 a view illus-
trating the recess in the saw blade for the reception of the planers.
On reference to Figures 1, 2, and 3, A represents part of the blade
and B the tooth, of which a is the point and 6 the base, the edges # of
the latter being parallel, or the base being a trifle wider above than
below. These edges x, x, have V-shaped grooves adapted to the
similarly shaped ribs on the edges y, y, of the recess D in the blade. A

page_text: recess d is cut in the base of the tooth, this recess being so formed as to
admit the end of a catch E, the latter having a projection e arranged to
pass into a notch f, which forms a continuation of the recess d in the
base of the tooth, the end of this notch being V-shaped to fit the grooved
end of the projection e on the catch. The base h of this catch is so
hooked as to fit and turn to a limited extent on the rounded projection i
of the blade, this projection being V-shaped to fit a groove made in the
hooked portion of the catch. One end of the bent spring F is secured to
the base of the catch, the upper end having a notched projection m
adapted to a V-shaped projection won the edge of the recess in the
blade. In driving the tooth into its place the rounded projection P on
its base comes in contact with the rounded portion of the projection e of
the catch E, thereby forcing the latter back, as shown in Figure 2.
When the lower edge of the base of the tooth however has reached the
shoulders q, q, of the recess of the blade, the projection e of the catch is
forced by the recoil of the spring F into the notch f in the recess of the
tooth, which is thus maintained tightly in its place by the catch, after
moving which back to the position shown in Figure 2 by a suitable
instrument the tooth can be readily withdrawn. It will be seen that
the tooth catch and spring are retained in their proper position laterally
by a suitable arrangement of grooves adapted to ribs on the edge of the
recess in the blade, and that no rivets tending to wound or warp the
latter are used. It will be evident that it is not absolutely necessary to
retain the precise form and disposal of parts illustrated and described in

page_text: projects on the opposite side of the blade, and this arrangement is
continued throughout.
In Figures 6, 7, 8, 9, and 10 the planers are separate from the teeth,
recesses being made between the latter in the blade for their reception.
Each recess X, Figure 10, is made of a dovetailed shape, and has an
edge 3 with a V-shaped groove adapted to a similarly shaped groove in
the rear edge of the planer X, the front edge 4 of which is bevilled from
one side, and adapted to the bevilled front edge 2 of the recess X. The
planer has a projection u on one side, terminating in the cutting edge w,
and at the opposite side a groove for the escape of the shavings, as
described in reference to Figures 4 and 5. In introducing the planer
into the recess X the former is held in the position shewn in Figure 8,
the rear V-shaped edge of the planer bearing against the grooved edge 3
of the recess; the front edge of the planer is then moved towards the
blade, and fitted to the bevilled edge 2 of the recess, where it is held by
a rivet passing through a hole 5 drilled partly in the planer and partly
in the blade, and countersunk on both sides, as seen in Figure 9.
Although the improvements above described have been illustrated as
applied to circular saws, it will be evident that they are applicable to
reciprocating and other saws, and that the planing device may be con-
nected with detachable teeth differing in form and construction to those
described.
Having now described the nature and object of the said Invention for
"Improvements in Saws," together with the manner in which the same
is to be or may be performed or carried into practical effect, I would
remark in conclusion that I claim as the Invention (communicated to
me by the above-named Gottlieb Maulick, Thomas Preston Marshall,
and George Whitfield Rowley),—
First. The detachable saw tooth B fitted to a recess in a blade, and
retained therein by a spring catch E, all substantially as and for the
purpose herein set forth.
Second. The formation on a detachable saw tooth of a planer,
substantially as specified.
Third. The planer Y adapted to a recess in a saw blade for ready
attachment to and withdrawal from the same, as set forth.

page_text: And, fourth. The recess or channel V in the blade, forming a
continuation of the groove of the planer, whether the latter be part of
the tooth or separate therefrom.
In witness whereof, I, the said Bristow Hunt, have hereunto set
my hand and seal, this Fourth day of August, in the year of our 5
Lord One thousand eight hundred and sixty-nine..
BRISTOW HUNT.. (L.S.);