IMPROVEMENTS IN TOOLS FOR CUTTING GLASS AND OTHER VITREOUS SUBSTANCES
Year: 1869

page_text: LETTERS PATENT to Martin Benson, of 9, Southampton Buildings,
Chancery Lane, London, for the Invention of "IMPROVEMENTS IN
TOOLS FOR CUTTING GLASS AND OTHER VITREOUS SUBSTANCES."-A com-
munication from abroad by Joseph Beales, Wendel Thornton Davis,
and Austin De Wolf, of Greendfield, County of Franklin, State of
Massachusetts, United States of North America.
PROVISIONAL SPECIFICATION left by the said Martin Benson at the
Office of the Commissioners of Patents, with his Petition, on the
26th May 1869..
I, MARTIN BENSON, of 9, Southampton Buildings, Chancery Lanc,
London, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN TOOLS FOR CUTTING GLASS AND OTHER VITREOUS SUBSTANCES," a
communication to me from abroad by Joseph Beales, Wendel Thornton
Davis, and Austin De Wolf, of Greendfield, County of Franklin, State
of Massachusetts, United States of North America, to be as follows:-
This Invention relates to an improvement in the art of cutting or
producing a continuous fracture along the surface of glass or other like

page_text: vitreous substance by compression, and consists of a tool composed of a
disk, and made to revolve on its axis as it is passed or drawn over the
surface to be fractured or cut. In practice the said disk is formed by
the end of a cylindrical shaft or spindle made of steel or other metal and
hardened; the disk or cutting end of the spindle should be about one-
twentieth of an inch in diameter, and when so made it has a cutting or
fracturing edge or angle of 90°. The shaft is mounted on a frame or
holder, and made to revolve on friction wheels or rollers to lessen
resistance as much as possible, and is held when in operation so that the
axis of the shaft is perpendicular to the line of progress or nearly so,
and at an angle of 45° to the surface of the glass, and when the tool is
in this position it is drawn forward by hand with a moderate downward
pressure, the angular edge of the disk in the meantime receives a lateral
rotative motion compared with the line of progress on the surface of the
glass, and thereby produces a continuous fracture similar to that made
by the downward. The shaft forming the disk or cutter is made to any
suitable length in order to give it stability while in motion, and is so
arranged to its frame or holder that it can be adjusted to its work by set
screws or other equivalent devices. The tool holder will be provided
with means for guiding it over the surface of the glass when making a
fracture or cutting, so that any form or shaped piece of glass or vitreous
substance may be cut.
The diamond alone has heretofore been available for the purpose of
cutting glass or other vitreous substances; the use of it for such purposes
requires considerable skill, which can only be attained by long practice,
and the tools themselves are not only costly but liable to injury from
accidental causes; by the use of this improvement these objections are
avoided or much lessened.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Martin Benson in the Great Scal Patent. Office on 30
the 18th November 1869.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of May, 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 successors, give
and grant unto me, the said Martin Benson, Her special licence that
I, the said Martin Benson, my executors, administrators, and assigns,
or such others as I, the said Martin Benson, my executors, adminis-
trators, 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 TOOLS
FOR CUTTING GLASS AND OTHER VITREOUS SUBSTANCES," a communication
from abroad by Joseph Beales, Wendel Thornton Davis, and Austin De
Wolf, of Greenfield, County of Franklin, State of Massachusetts,
United States of North America, upon the condition (amongst others)
that I, the said Martin Benson, my exccutors or administrators, by
an instrument in writing under my, or their, or one of their hands
and scals, 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 calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Martin Benson, 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 :—
This Invention relates to an improvement in the art of cutting or
producing a continuous fracture along the surface of glass or other like
vitreous substance by compression, and consist of a tool composed of a
disc, and made to revolve on its axis as it is passed or drawn over the
surface to be fractured or cut. In practise the said disc is formed by the
end of a cylindrical shaft or spindle made of steel or other metal and
hardened; the disc or cutting end of the spindle should be about
onc-twentieth of an inch in diameter, and when so made it has a cutting
or fracturing edge or angle of 90°. The shaft is mounted on a frame or
holder and made to revolve on friction wheels or rollers to lessen

page_text: resistance as much as possible, and is held when in operation so that
the axis of the shaft is perpendicular to the line of progress or nearly so,
and at an angle of 45° to the surface of the glass, and when the tool is in
this position it is drawn forward by hand with a moderate downward pres-
sure, the angular edge of the disc in the meantime receives a lateral rotative
motion compared with the line of progress on the surface of the glass,
and thereby produces a continuous fracture similar to that made by the
diamond. The shaft forming the disc or cutter is made to any suitable
length in order to give it stability while in motion, and is so arranged to
its frame or holder that it can be adjusted to its work by set screws or
other equivalent devices. The tool holder will be provided with means
for guiding it over the surface of the glass when making a fracture or
cutting, so that any form or shaped piece of glass or vitreous substance
may be cut.
The diamond alone has heretofore been available for the purpose of
cutting glass or other vitreous substances: the use of it for such purposes
requires considerable skill, which can only be attained by long practice,
and the tools themselves are not only costly but liable to injury from
accidental causes; by the use of this improvement these objections are
avoided or much lessened.
Having thus described the nature of the said Invention I will proceed
more fully to describe the manner of performing the same, referenco
being had to the annexed Drawings, and to the letters and figures of
reference marked thereon.
Figure 1 represents an elevation of the disc or cutter detached from its
frame or holder; Figure 2 represents a perspective view of the bottom
of the tool complete; Figure 3 represents a cross soctional elevation of
the tool greatly enlarged.
•
The cylindrical shaft A is formed with one conical end to fit a
corresponding socket or set screw B, and at its other end is formed with
a disc or face C at right angles with the axis of the shaft. The angle D
at the intersection of the disc and cylindrical surfaces of the shaft A
forms the cutting edge of the tool. An angle of 90° at D secures the
maximum of strength and efficiency. The efficacy of the tool is
increased as the diameter of the disc is reduced, but there are limits
below which it is not practicable to go without an unsafe reduction of
strength, therefore the end of the shaft A is reduced, as shown, so that

page_text: the diameter of the disc C shall be about one-twentieth of one inch,
which may be regarded about the proper dimension. The effective
operation of this apparatus depends upon the degree of freedom with
which the cutter C may revolve as it is moved across the surface of the
glass. The shaft A is therefore made to rest and revolve on the friction
wheels E, E, near the cutting end or disc, and thereby the frictional
resistance to the revolution of the cutter C is much lessened. The
friction wheels E, E, have their bearings in a frame, which also supports
thic socket or set screw B for the conical end of the shaft A. This shaft
requires to be of length sufficient to give the necessary steadiness in
operating, and for that purpose I place the socket or set screw B at the
oxtremity of the arm G, as represented in Figure 2 and 3. While in
operation the shaft bears upon the friction wheels E, E, and is at the
same time pressed towards the socket or set screw B, and thereby
prevents its displacement, but when not in use, unless retained in place
by some means provided for that purpose, the cutter would become
detached from tho othor parts of the apparatus; to guard against this the
staple I is screwed to the frame, and it passes over the shaft A so as to
confine it to its bearing upon the friction wheels E, E, and the collar J
is placed upon the shaft A between the staple I and sockot B to prevent
an end movement of the shaft sufficient to disengage it from the socket
set screw B. When, however, it is necessary for the purposes of adjust-
ment the collar J may be constructed to slip as far as necessary, and this
adjustment may be secured at any time by turning the set screw H. In
operation the tool should be held lightly between the finger and thumb
and the shaft A perpendicular to line of progression, and at an angle
of about 45° to the surface of the glass; the guides K, K, may rest
against the edge of the rule, guide piece, or pattern; press gently upon
the tool and draw it forward with a firm and regular motion and a
continuous fracture will be produced, through which the glass may be
divided as though it had been cut with a diamond. The great efficiency
of the tool will depend on the sharpness of the disc or angle D. By
constant use it will become rounded or dull, in such cases it may bo
sharpened by an ordinary stone used for sharpening carpenters' chisels.
This is accomplished by cutting away the end of the disc or spindle
until the angle D is made perfect, as the disc wears away by use the
spindle A is shortened, which can be set up or adjusted by the set
Screw

page_text: Having now described the construction, manner of using, and the
principle on which the disc cutters is made to act, I wish it understood
that I do not claim the particular manner of making the tool as described,
nor the material of which it is composed; but what I do claim as new is
a disc or tool for cutting glass or other vitreous substances mado and
constructed to operate substantially as described, or in any other equi-
valent manner, by which the disc can be made to act on the surface of
the glass in the manner and for the purpose bofore described in the
foregoing Specifications.
In witness whereof, I, the said Martin Benson, have hereunto set
my hand and scal, this Eighteenth day of November, in the year
of our Lord One thousand eight hundred and sixty-nine.
MARTIN BENSON. (L.S.)