IMPROVEMENTS IN THE MANUFACTURE OF THE PISTONS, SLIDE VALVES, AND STUFFING BOXES OF STEAM ENGINES
Year: 1854

page_text: LETTERS PATENT to John Penn, of Greenwich, Engineer, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF THE PISTONS, SLIDE
VALVES, AND STUFFING BOXES OF STEAM ENGINES."
Sealed the 29th December 1854, and dated the 23rd October 1854.
PROVISIONAL SPECIFICATION left by the said John Penn at the Office
of the Commissioners of Patents, with his Petition, on the 23rd October
1854.
I, JOHN PENN, of Greenwich, Engineer, do hereby declare the nature of
the Invention for "IMPROVEMENTS IN THE MANUFACTURE OF THE PISTONS, SLIDE
VALVES, AND STUFFING BOXES OF STEAM ENGINES" to be as follows:-*
This Invention consists of constructing the pistons, slide valves; and stuffing
boxes of steam engines with wood packings; for which purpose the wood
packings are made in the form of sections or rings, according to the class of
packing required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Penn in the Great Seal Patent Office on the 23rd April
1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
PENN, of Greenwich, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of October, in the year of our Lord
One thousand eight hundred and fifty-four, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said John Penn, Her special licence that I, the said John Penn, my executors,
administrators, and assigns, or such others as I, the said John Penn, 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 THE MANUFACTURE OF THE
PISTONS, SLIDE VALVES, AND STUFFING BOXES OF STEAM ENGINES," upon the condition
(amongst others) that I, the said John Penn, by an instrument in writing
under my hand and seal, 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 Penn, 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):
This Invention consists of constructing the pistons, slide valves, and stuffing
boxes of steam engines with wood packings; for which purpose the wood
packings are made in the form of sections or rings, according to the class of
packing required.
Having thus stated the nature of my said Invention, I will proceed to
describe the manner of performing the same.
DESCRIPTION OF THE DRAWING.
Figure 1 shows a section of part of a steam cylinder with slide valve and
piston with packings of wood, according to my Invention; Figure 2 is a trans-
verse section of the cylinder and slide valve; Figure 3 shows a side view of a

page_text: piston separately; and Figure 4 shows a plan of the slide valve. a is the
piston, which is formed with two metal rings b, b, similar to what have before
been used, and this is the form of piston I prefer to employ when applying my
Invention to the pistons of steam engines. I would, however, remark that
other forms of parts of pistons may be used when carrying out my improvements.
The rings b, b, are grooved, to receive and have wood packings affixed thereto;
and I prefer that each metal ring b should have a fillet of wood c in the groove,
as shewn, and fixed by means of screws to the metal rings. The wood pack-
ings may, however, be of other forms, and fixed by other means. d, d, are the
wood packings of the slide valve; they are laid into and fixed by screws in
recesses formed in the face of the slide valve, as shown; or the wood packings
may be otherwise fixed to the face of the slide. When the stuffing boxes of
steam engine cylinders are to be packed with wood, I prefer to employ metallic
rings made to press up to and embrace the piston rod. I make such rings
with grooves or recesses, and fix wood therein, as is shown at Figures 5, 6,
and 7, where a stuffing box is shown composed of two rings, with wood inlaid
and fixed therein, and such rings are pressed towards the piston rod either by
springs a, or by hemp packing pressed into the space behind the rings e, e,
which are lined with wood.
c,
Having thus described the nature of my said Invention, and the manner
of performing the same, I would have it understood that I do not confine
myself to the details herein shown and described; but what I claim is, the
construction of pistons, slides, and stuffing boxes of steam engines of wood
packings.
In witness whereof, I, the said John Penn, have hereunto set my hand
and seal, this Twenty-third day of April, in the year of our Lord Ono
thousand eight hundred and fifty-five.
Witness,
B. GOBEY,
4, Old Square, Lincoln's Inn.
JOHN PENN. (L.S.)