IMPROVEMENTS IN CONSTRUCTING PISTONS
Year: 1847

page_text: Pistons.
RICHARDS SPECIFICATION."
TO ALL TO WHOM THESE: PRESENTS: SHALL COME, I; JAMES
RICHARDS, of New York, United States of America, Engineer, send greeting.
WHEREAS Her present most Excellent. Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date, at Westminster, the Twelfth day of June,
One thousand eight hundred and forty-seven, in tho tenth year of Her reign,
did; for Herself, Her heirs and successors, give and grant unto me, the said
James Richards, my exors, admors, and assigns, Her especial licence, full
power sole privilege and authority, that I, the said James Richards, my
exors, admors, and assigns, or such tothers as the said James Richards,
my- exors, adiñors, or assigns should at any time agree with, and no others,
from time to time and at all times during the term of years therein expressed,
should and lawfully might makes use, exercise and vend; within England,
Wales; and the Town of Berwick-upon-Tweed and in the Islands of Jersey,
Guernsey, Alderney, Sark, and Mans and in all Her said Majesty's Colonies
and. Plantations abroad, my Invention of "IMPROVEMENTS IN CONSTRUCTING
PISTONS" in which said Letters Patent is contained a proviso that I, the said
James Richards, shall cause a particular description of the nature of my said
Invention, and in what manner the same is to be performed, by an instrument
in writing under my hand and seal; to be enrolled in Her said Majesty's
High Court of Chancery within six calendar months next and immediately.
after the date of the said in part recited Letters Patent, as in and by the same,
reference being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
James Richards; do hereby declare that the nature of my said Invention,
**

page_text: thereon, that is to say:-
DESCRIPTION OF THE DRAWINGS.
Figure 1 shows a section of a piston constructed according to my Invention.
Figure 2 shows a plan of the piston, with the top plate or cover removed.
Figure 3 shows a plan of one of the spring packing rings separately. Figure 4
shows a section of the two spring packing rings, by which the manner of
splitting them can be better understood than in the other Figures of the
Drawings. Figure 5 shows a plan, and Figure 6 a side view of the lower
plate of the piston. Figure 7 shows the under side view and edge view of the
upper plate or cover of the piston. Figuro 8 shows the form of the segmental
wedges by. which the spring packing rings are moved, and Figure 9 shows, the
springs used for pressing the wedges outwards. a is the lower plate or part
of the piston which is fixed to the end of the piston rod in the ordinary
manner; and it will be seen that its upper edge at a¹ is bevelled to correspond
with the bevel formed on one of the two spring packing rings b. The upper
plate or cover of the piston c has a similar bevelled edge c¹, and corresponding
with the bevel formed on the other of the spring packing rings b; and it is the
forming of bevels on the plates a and c corresponding with the bevels formed on
the outer surfaces of the two packing rings b, which constitutes the peculiarity
of this Invention; for I would wish it to be understood that I am aware that
two spring packing rings have been used in making metal pistons before; I
do not, therefore, claim the use of such like rings generally for packing
pistons, but only when their edges are formed with bevels working against
bevels formed on the upper and lower plates of the piston. The spring rings
b, b, may be forced out in any of the modes heretofore resorted to by others
when using two spring rings as the packing of a piston; but I employ several
wedges d, d, d, each acted on by its own spring e, e, e, as shown, the wedges d
being so formed as to enter: between the bevelled inner surfaces of the spring
packing rings b, b, and thus cause the wedges d, as they move outward, not
only to expand the two spring packing rings 6, but at the same time cause the
spring packing rings to separate one from the other. The packing rings b, b,
are made, as heretofore, in the form of a complete ring, and then cut so that
they become circular springs. In cutting the spring packing rings b, b, they
are to be so cut as to prevent the steam passing into the interior of the piston;
and this is done by cutting a vertical cut from 1 to 2, which is not so deep as

page_text: the level a', c', formed respectively on the plates a and c of the piston; then
the cut is made horizontally from 2 to 3, the surfaces so produced by the hori-
zontal cut being made to keep at all times in contact; and it will be seen that
the horizontal cuts of the two spring rings b, b, will be at all times covered at
the back by the bevelled surfaces a¹, c', respectively, and the cut from 3 to 4 is
vertical. The cut need not be exactly as here stated; but however the cut is
made, care is to be observed that it does not admit of the steam passing by it
to and from the interior of the piston. By this arrangement or construction
of the parts it will be found that the two spring packing rings of which the
packing of a piston may be formed, will be found to work better in respect to
its surfaces where they come in contact with the plates a and c.
Having thus described the nature of my Invention, and the manner in
which the same is to be performed, I would have it understood that I do not
confine myself to the details herein described so long as the peculiar cha-
racter of my Invention be retained. But what I claim is, the combining
the use of bevelled surfaces on packing rings 6 and the plates a, c, as herein
described. And I also claim the mode of employing a series of wedges and
separate springs for forcing out the packing rings b.
In witness whereof, I, the said James Richards, have herento set my
hand and seal, this Tenth day of December, in the year of our Lord
One thousand night hundred and forty-seven
JAMES (L.s.) RICHARDS.
AND BE IT REMEMBERED, that on the Tenth day, of December, in
the year of our Lord 1847, the aforesaid James Richards came before our
5 said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Eleventh day of December, in the year of our Lord One
thousand eight hundred and forty-seven.