IMPROVEMENTS IN HYDRAULIC PRESSURE GAUGES SUITABLE FOR MEASURING THE PRESSURE IN THE CYLINDERS OF HYDRAULIC PRESSES
Year: 1863

page_text: LETTERS PATENT to Sydney Smith, of the Hyson Green Brass Works,
near Nottingham, for the Invention of "IMPROVEMENTS IN HYDRAULIC
PRESSURE GAUGES SUITABLE FOR MEASURING THE PRESSURE IN THE CYLINDERS
OF HYDRAULIC PRESSES."
Sealed the 18th March 1864, and dated the 5th December 1868.
PROVISIONAL SPECIFICATION left by the said Sydney Smith at the
Office of the Commissioners of Patents, with his Petition, on the 5th
December 1863.
I, SYDNEY SMITH, of the Hyson Green Brass Works, near Nottingham, do
hereby declare the nature of the Invention for "IMPROVEMENTS IN HYDRAULIC
PRESSURE GAUGES SUITABLE FOR MEASURING THE PRESSURE IN THE CYLINDERS OF
HYDRAULIC PRESSES," to be as follows:--
For
This Invention has for its object improvements in hydraulic pressure gauges
suitable for measuring the pressure in the cylinders of hydraulic presses.
this purpose I put the hydraulic cylinder (or other vessel containing fluid
under pressure) in communication with a chamber containing a plunger of
small diameter; this plunger passes through a cupped leather, by which the
plunger is free to move up and down, whilst at the same time it is fluid-tight.
At the upper end of the plunger is fixed or formed a disc, which, when the
plunger is raised, acts against the apex of a conically-coiled spring and presses
it towards its base. The motion thus obtained is communicated by a rod
having a toothed rack at its upper end, which gears with and gives motion to

page_text: a pinion on the axis of a pointing hand, and such pointing hand points
to divisions on a graduated dial plate in the ordinary manner of pressure
gauges.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Sydney Smith in the Great Seal Patent Office on the
2nd June 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SYDNEY
SMITH, of the Hyson Green Brass Works, near Nottingham, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of December, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-seventh year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Sydney Smith, Her special licence that I, the said Sydney Smith,
my executors, administrators, and assigns, or such others as I, the said
Sydney Smith, 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
HYDRAULIC PRESSURE GAUGES SUITABLE FOR MEASURING THE PRESSURE IN THE
CYLINDERS OF HYDRAULIC PRESSES," upon the condition (amongst others) that
I, the said Sydney Smith, my executors or administrators, by an instru-
ment 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 Sydney Smith, 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 thereof, that is to say :-
For
This Invention has for its object improvements in hydraulic pressure gauges
suitable for measuring the pressure in the cylinders of hydraulic presses.
this purpose I put the hydraulic cylinder (or other vessel containing fluid
under pressure) in communication with a chamber containing a plunger of
small diameter; this plunger passes through a cupped leather, by which the

page_text: plunger is free to move up and down, whilst at the same time it is fluid-tight.
At the upper end of the plunger is fixed or formed a disc, which, when the
plunger is raised, acts against the apex of a conically-coiled spring and presses
it towards its base. The motion thus obtained is communicated by a rod,
having a toothed rack at its upper end, which gears with and gives motion
to a pinion on the axis of a pointing hand, and such pointing hand points
to divisions on a graduated dial plate in the ordinary manner of pressure
gauges.
Having thus stated the nature of my Invention, I will proceed to describe
more fully the manner of performing the same.
DESCRIPTION OF THE DRAWING.
The Drawing hereunto annexed shows a vertical section of a hydraulic
pressure gauge constructed according to my Invention.
a is a chamber formed in a casting suitably shaped at its lower end for
being screwed on to the end of a pipe leading from a hydraulic cylinder or
other vessel containing fluid under pressure. The chamber a contains a
plunger 6 of small diameter. At the top of the chamber is a cupped leather c
through which the plunger passes; the cupped leather is held down in its
place by the plate d, as is shown; e is a disc at the top of the plunger, which,
when the plunger is raised, comes against the apex of a conically-coiled spring f
and presses it upwards towards its base. The bottom of the rod 9 rests on
the central part of the spring, and so rises and falls with it; the upper end of
the rod is formed into a rack which gears with a pinion on the axis of the
pointing hand h which points to divisions on a graduated dial plate in the
ordinary manner of pressure gauges and so indicates the hydraulic pressure on
the dial. The graduated dial plate is not shown in the Drawing.
In witness whereof, I, the said Sydney Smith, have hereunto set my hand
and seal, this Thirty-first day of May, in the year of our Lord One
thousand eight hundred and sixty-four.
SYDNEY SMITH. (L.S.)