Improvements in and relating to Mortising Chisels.
Year: 1898

page_text: Date of Application, 27th Jan., 1898-Accepted, 28th May, 1898
COMPLETE SPECIFICATION.
Improvements in and relating to Mortising Chisels.
I, WILLIAM POTTER, of 245, West 109th Street, New York City, in the County
of New York and State of New York, Gentleman, do hereby declare the nature of
my invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
-
The object of my invention is to construct a mortising chisel in such a manner
that the chips, whether large or small will have a free and ready passage from
the cutting edge to the discharge point, a predetermined distance from said edge.
Another object of the invention is to provide a means whereby the chips will be
confined to the chisel for a certain distance from the cutting point, yet be free
to move rearward to their point of exit. A further object of the invention is
to construct the chip-receiving channel of the chisel so that the chips can not
slide forward and impede the backward movement of the chips as they are
newly made by the cutting edge of the tool.
The invention consists in the novel construction and combination of the several
parts, as will be hereinafter fully set forth and pointed out in the claims.
Reference is to be had to the accompanying drawings forming a part of this
specification, in which similar characters of reference indicate corresponding
parts in all the figures.
Figure 1 is a perspective view of the chisel.
Figure 2 is a longitudinal vertical section through the chisel.
Figure 3 is a plan view of the chisel.
Figure 4 is a front elevation.
Figure 5 is a section on the line 5-5 of Figure 2.
Figure 6 is a section on the line 6-6 of Figure 2.
The body A of the chisel is provided with a longitudinal floor 10, constituting the
bottom of the chip-receiving channel B. The floor 10 is of equal width through-
out its length; and its forward end 11 is inclined or beveled, terminating at the
plane of the under face of the chisel in a comparatively sharp edge 12.
The
rear end wall 13 of the channel B is upwardly curved, and the floor 10 is parallel
with the face of the chisel from the forward end of the cutting edge rearward,
as shown in Figure 2. The side walls 14 of the chisel may be given any
desired exterior shape, and are preferably exteriorly concaved, while interiorly
the side walls of the chisel are beveled or inclined in opposite directions from the
floor 10, as shown at 15 in the drawings.
At the cutting point of the chisel the side walls 14 are curved inward over the
floor to a predetermined extent, forming thereby flanges 16. The flanges extend a
predetermined distance rearward, and then lose themselves in the side walls. The
flanges serve to prevent the chips from being forced out of the channel at the
cutting point of the chisel, yet the flaring walls of the chip-receiving channel B
will admit of the chips moving freely rearward until they are clear of the flanges 16,
whereupon they find a ready exit from said channel. The front end portions 17
of the chisel are fluted as at 18, and constitute the cutting edges, together with
the edge 12 at the forward end of the floor 10; but the fluted cutting edges project

page_text: beyond the aforesaid edge 12 of the floor as shown in the drawings, thus reducing
the friction and directing the chips into the chip-receiving channel.
Preferably, as shown in the drawings, the side walls of the channel in the
chisel may be rounded off where the said side walls meet the bottom wall of the
channel, or the said side walls may meet the bottom wall at an angle, as in
practice may be found most desirable.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
1. A chisel, the chip-receiving channel whereof has its side walls beveled
outwardly in opposite directions, substantially as described.
2. A mortising chisel, the side walls of the chip-receiving channel whereof are
provided with a floor of uniform width, having an upward inclination from the
cutting edge of the chisel for a short distance only and running parallel with
the face of the chisel and having the interior faces of its side walls beveled
upwardly and outwardly, as and for the purpose specified.
3. A mortising chisel, the chip-receiving channel whereof is provided with
a floor inclined as heretofore described, and side walls having their inner faces
beveled upwardly in opposite directions, the said side walls being provided with
inwardly extending flanges, commencing at the cutting edge of the chisel and
extending a predetermined distance rearward, as and for the purpose specified.
4. A mortising chisel, provided with a chip-receiving channel, the floor whereof
is of uniform width and is given an upward inclination from the cutting edge,
the forward portion of the floor being downwardly curved and the side walls having
their inner faces upwardly inclined in opposite directions, 'the said side walls
extending.beyond the forward end of the floor, having their forward ends fluted,
forming cutting edges, and flanges formed upon the side walls of the said channel,
extending in direction of each other over the floor, the flanges being tapering and
losing themselves in the side walls of the channel at a point between the centre
of said channel and its rear end wall, as and for the purpose specified.
Dated this 27th day of January 1898
FELL & JAMES,
Agents for the Applicant.