A NEW OR IMPROVED GUAGE FOR GUAGING WIRE AND SHEET METAL, AND FOR OTHER LIKE PURPOSES
Year: 1857

page_text: LETTERS PATENT to John Abraham, of Birmingham, in the County of
Warwick, Machinist, for the Invention of "A NEW OR IMPROVED GUAGE
FOR GUAGING WIRE AND SHEET METAL, AND FOR OTHER LIKE PURPOSES."
Sealed the 5th February 1858, and dated the 17th August 1857.
PROVISIONAL SPECIFICATION left by the said John Abraham at the
Office of the Commissioners of Patents, with his Petition, on the 17th
August 1857.
I, JOHN ABRAHAM, of Birmingham, in the County of Warwick, Machinist,
do hereby declare the nature of the Invention for "A NEW OR IMPROVED
GUAGE FOR GUAGING WIRE AND SHEET METAL, AND FOR OTHER LIKE PURPOSES,"
to be as follows:-
My new or improved guage consists of two pieces or jaws of steel or other
metal; one of which slides and the other is fixed upon a bar. The pieces or
jaws are made to approach towards or recede from one another in the manner
herein-after described. The wire, sheet metal, or other article, the diameter,
thickness, or size of which is to be measured, is introduced between the said
two pieces or jaws of. steel, which are brought into contact with the article,
and the distance of the two pieces or jaws is ascertained as herein-after
explained. The motion of the moveable piece or jaw upon the bar is effected
by a screw, which passes through both pieces. The said screw is of a different

page_text: pitch at its ends, one half the screw being of any given pitch, and the other
half of a greater or less pitch. When the said screw is turned, the two
pieces advance upon it to different distances, the pieces being brought together
or separated on each rotation of the screw by a distance equal to the difference
in the pitch of the screws. For example, if the screws differ in pitch by one-
hundredth of an inch, then on each rotation of the screw one of the jaws will
move on the screw to a greater or less distance than the other equal to the
hundredth of an inch. The motion of the screw through one-tenth of a
complete rotation will produce a relative motion in the pieces or jaws equal
to one-thousandth of an inch, and so on for different degrees of rotation. The
head of the screw is divided into ten or other number of divisions, and the
angle through which it has been turned is indicated against a fixed mark on
the instrument.
The number of complete rotations of the screw is read off on the side of
the instrument, and the fractional part of the rotation by the head of the screw
as described. The article to be measured is placed between the jaws, and the
jaws being brought in contact with the article, the amount of rotation in the
screw necessary to close the jaws upon the article is read off as described, and
the size of the article thus determined. I sometimes insert a screw collar
between one of the jaws and the part of the screw on which it works; by
turning the said collar, the jaw in which it works may be moved at each
rotation through a distance equal to the pitch of the screw.
ว
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed.
by the said John Abraham in the Great Seal Patent Office on the
15th February 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ABRAHAM, of Birmingham, in the County of Warwick, Machinist, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventeenth day of August, in the year of our Lord
One thousand eight hundred and fifty-seven, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Abraham, Her special licence that I, the said John Abraham,
my executors, administrators, and assigns, or such others as I, the said John
Abraham, 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

page_text: 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 "A NEW OR IMPROVED GUAGE FOR
GUAGING WIRE AND SHEET METAL, AND FOR OTHER LIKE PURPOSES," upon the con-
dition (amongst others) that I, the said John Abraham, 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 calendar.
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Abraham, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
My new or improved guage for guaging wire, sheet metal, and for other
like purposes is constructed in the manner herein after particularly described,
and illustrated in the accompanying Drawing.
Figure 1 represents my new or improved guage in side elevation; and.
Figure 2 represents the same in plan; Figure 3 represents a transverse section.
of the same taken through the line a, Figure 2; and Figure 4 represents a.
transverse section of the same taken through the line 3, Figure 2. c, d, are:
two jaws or pieces of steel or other metal, one of which c slides to and fro in
the manner herein-after explained, and the other d is fixed. The wire, sheet
metal, or other article, the diameter, thickness, or size of which is to be
measured, is introduced between the two jaws c, d, which jaws are brought
into contact with the wire, sheet metal, or other article, and the distance of the
two jaws is read off on the graduated parts of the instrument, as herein-after
explained. e is a.screw, which passes through the screw boxes c', d', on which
the jaws c, d, are fixed respectively. The said screw e is of a different pitch at
its two ends, one half of the screw being of any given pitch, and the other
half of a greater or less pitch. When the said screw e is turned by the milled
nut f fixed on its end, the screw boxes c¹, d', and consequently the jaws c, d,
are brought together or separated during each rotation of the screw e by a
distance equal to the difference in the pitch of the two portions of the screw e.
For example, if the two portions of the screw e differ in pitch by one-
hundredth of an inch, then on each rotation of the screw e one of the jaws c, d,
will move on the said screw e to a greater or less distance than the other by.
one-hundredth of an inch. The motion of the screw e through one-tenth of a.
complete rotation will produce a relative motion in the jaws c, d, equal to one-

page_text: thousandth of an inch, and so on for different degrees of rotation. The head
of the screw is divided into ten or other number of divisions, as shown at g,
and the angle through which it has been turned is indicated by the fixed
marker (see Figure 2). The number of complete rotations is read off on the
side of the instrument at i. The bar k carries a scale of figures situated at a
distance from each other equal to the distance of the threads on the end e² of
the screw e, and the figure which is presented at the hole i indicates the
number of rotations which the screw e has made, and the number of hundredths
of an inch between the jaws c, d. The fractional part of a rotation of the
screw is indicated by that numeral of the series of figures at g which is
brought opposite to the marker h; thus, as the instrument is represented in
the Drawing, the numerals indicate that the jaws c, d, are at a distance apart
equal to four-hundredths and nearly one-thousandth of an inch, and so on; by
turning the nut f until the jaws c, d, grasp the article between them, the
thickness of the article is indicated in hundredths and thousandths of an inch.
Instead of making the end 3 of the screw e work directly in the screw box c¹,
I prefer to insert a screw collar between the screw e and the screw box c¹,
the said screw collar 7 being tubular, and screwed within. The screw e in this
case works in the screw collar I, turning freely in the screw box c¹. By turning
the collar by means of the milled nut m, the jaw c may be made to advance
upon the end of the screw e, and as the said screw in this case remains
stationary, the action is not a differential one, but the jaw c is moved back-
ward or forward at each rotation of the collar 1, equal to the distance between
the threads on the end e³ of the screw e, and as the said threads are one-tenth
of an inch apart, each rotation of the collar moves the jaw c one-tenth of an
inch. In measuring articles more than one-tenth of an inch in diameter, the
nut m is turned through one rotation and fixed firmly in its position by a
screw n engaging in a hole in the collar I, as seen in the section, Figure 3;
the precision of the position of the collar 7 after its rotation is thus secured;
or the collar may be made to perform any number of rotations, and again
fixed by the screw n engaging in a hole in the said collar, and fixing it as
described.
The number of rotations made by the collar is indicated at by a series
of figures made upon the screw box c¹. The numeral presented at,o indicates
the number of tenths of an inch by which the jaws c, d, are separated, to which
must be added the number of hundredths indicated at i, and the number of
thousandths indicated at h.
Having now described the nature of my Invention, and the manner of
carrying the same into effect, I wish it to be understood that I do not limit

page_text: myself to the precise details herein described and illustrated, as the same may
be varied without departing from the nature of my Invention; but I claim as
my Invention, the new or improved guage for guaging wire and sheet metal,
and for other like purposes, herein-before described, and illustrated in the
accompanying Drawing, that is to say, a guage in which the article to be
measured is grasped between two jaws made to approach or separate by a
differential screw, or a screw having threads of different pitches on different
parts, the amount of rotation of the said differential screw and the thickness
of the article being indicated in the manner berein-before described and
represented.
In witness whereof, I, the said John Abraham, have hereunto set my
hand and seal, this Twelfth day of February, in the year of our Lord
One thousand eight hundred and fifty-eight.
5 Witness,
GEORGE SHAW.
JOHN ABRAHAM. (L.S.)