CERTAIN IMPROVEMENTS IN THE CON- STRUCTION AND ADAPTATION OP METALLIC PACKINGS FOR THE PISTONS OF STEAL AND OTHER ENGINES, PUшPS, AND OTHER PURPOSES TO WHICH THE SAME MAY BE APPLI- CABLE
Year: 1834

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, wc, BENJAMIN
HICK, of Bolton-le-Moors, in the County Palatine of Lancaster, Engineer,
Edward Evans, the elder, of Oldham, in the said County, Coal Proprictor, and
John Higgins, of Oldham aforesaid, Engineer, send greeting.
WHEREAS His most Excellent Majesty King William the Fourth, by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Fourth day of July, in the fifth year of His reign, did, for
Himself, His heirs and successors, give and grant unto us, the said Benjamin
Hick, Edward Evans, and John Higgins, our executors, administrators, and
assigns, His especial licence, full power, sole privilege and authority, that we,
the said Benjamin Hick, Edward Evans, and John Higgins, our executors,
administrators, and assigns, or such others as we, the said Benjamin Hick,
Edward Evans, and John Higgins, our executors, administrators, or assigns,
should at any time agree with, and no others, from time to time, and at all
times thereafter during the term of years therein expressed, should and lawfully
might make, use, exercise, and vend, within that part of the United Kingdom
of Great Britain and Ireland called England, His Dominion of Wales, and Town
of Berwick-upon-Tweed, our Invention of "CERTAIN IMPROVEMENTS IN THE CON-
STRUCTION AND ADAPTATION OP METALLIC PACKINGS FOR THE PISTONS OF STEAL AND
OTHER ENGINES, PUшPS, AND OTHER PURPOSES TO WHICH THE SAME MAY BE APPLI-
CABLE;" in which said Letters is contained a proviso that if we, the said
Benjamin Hick, Edward Evans, and John Higgins, should not particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, by an instrument under our hands and seals,
or under the hand and seal of one of us, and cause the same to be inrolled
in His Majesty's High Court of Chancery within six calendar months next
and immediately after the date of those Letters Patent, that then those Letters

page_text: Patent, and all liberties and advantages whatsoever thereby granted, should
utterly cease, determine, and become void, anything therein-before contained
to the contrary notwithstanding, as in and by the said Letters Patent, on
reference being thereunto had, will more fully and at large appear.
NOW KNOW YE, that we, the said Benjamin Hick, Edward Evans the
elder, and John Higgins, do hereby declare that our improved metallic piston
consists principally of rings formed and placed on the block of the piston, in
such a manner as effectually to prevent the passage of steam between the
piston and the cylinder within which it works. It is also applicable to the
air pumps of steam engines, blowing cylinders, water and other pumps, whose
dimensions require their buckets to be packed with hemp or other vegetable
substances. Our piston is distinguished from the metallic pistons in common
use by its not requiring springs or other distinct mechanical contrivances to
press the rings outwards, in order to keep them in sufficiently close contact
with the cylinder or barrel. This purpose is elected in our improved piston
by the gravitating action of the rings themselves, which repose freely on an
inclined bed turned on the block of the piston, and are thus impelled by their
own weight against the cylinder or pump barrel with the requisite degree of
force to ensure tightness. This principle of obtaining tightness laterally
through the action of gravity, or, in other words, through the tendency of the
rings to descend on the block of the piston, is susceptible of many modifica-
tions in practice.
We have in the Drawings hereunto annexed exhibited two modes of con-
structing the pistons of steam engine cylinders, and a third mode suited to an
air pump bucket. The piston represented in the Figures 1, 2, 3, 4, 5, and 6
is 32 inches in diameter. The angle made by the bed of the piston block b, b,
and also by the corresponding face of the rings c, d, with the cylinder e, e, is,
in Figures 2, 3, and 4, about fifty-five degrees. The weight of the rings in
cast iron is about one hundred and fifty pounds. The angle of the rings, and
their weight, above assigned, are proper for condensing engines worked by
steam of the ordinary pressure; but for condensing or non-condensing engines
worked by steam, termed high pressure, it will be requisite to increase the
pressure of the rings of the piston against the cylinder. This may readily be
accomplished, either by diminishing the angle of the rings, and of the bed or
seat on which they rest, or by increasing the weight of the rings themselves.
Figure 1 is a plan or bird's-eye view of the upper part of the piston.
Figure 2 is a section of the rings and cover through the line a, a, Figure 1.
Figure 8 is a section of the rings and cover through the line y, y, Figure 1.
Figure 4 is a plan of the piston with its cover removed, shewing the upper
surface of the rings c.

page_text: The same letters refer to similar parts in all the Figures before and after
mentioned. b, b, is the central block of the piston, which is made fast to the
conical end of the piston rod a in the usual manner. c, d, are two separate
rings of cast iron, brass, or other metal, accurately turned and ground toge-
ther; they are also accurately turned and ground to fit the piston block b, b,
and the cylinder e, e. The rings c, d, after being thus fitted and ground, are
each cut into three, four, or more equal parts or segments, in proportion to the
diameter of the cylinder, and are placed together in such way that the joints
of the one ring cross the joints of the other, as seen in Figure 4, and effec-
tuatey prevent the passage of steam, air, or other fluids. In order to stop any
motion which the rings might acquire round the block of the piston, the pin f
is fixed in the block which enters into a mortice formed in the ring c, allowing
sufficient play therein not to impede the free descent of the rings on the
angular bed of the block; and in order to prevent the motion of the ring d
round the ring c, a similar pin is introduced to unite them. The cover g is
accurately fitted to the block of the piston, and secured to it by the four
bolts h, h, h, h. The cover is prevented from pressing upon the rings by the
four setting screws i, i, i, i, which are screwed into and through the cover,
so that their ends project and rest upon the solid block. Thus the cover g
can be adjusted so as to be brought so near to the rings that no dirt can enter
between it and them, and yet be prevented from pressing upon the rings, and
as the rings or segments wear away the cover can be followed down in pro-
portion. A recess k, k, is formed in the upper part of the cover, in order to
hold a small quantity of hemp or other vegetable packing, for the purpose of
retaining a portion of the condensed steam, or of the oil or grease occasionally
used in lubricating the piston and cylinder. This packing is held down by
wrought iron ring, 1, 1, which is secured to the cover 7 by eight small
crews, m, m.
A modification of the piston above described is exhibited in Figure 5,
wherein it will be seen that we employ three rings, c, d, n, two of which, c, d,
est upon a flat base turned on the block instead of an angular one, the lateral
ressure against the cylinder or barrel being in this case obtained by the
ravity of the wedge-shaped entire ring of metal n, fitted and ground to a
orresponding angle in the internal face of the spring c, and to the vertical
ce of the block of the piston.
Figure 6 represents an external elevation of the piston completely fitted
r work.
Figures 7, 8, and 9 represent a third modification of the gravitating piston
ngs, as applied to and suitable for an air pump bucket. The construation.

page_text: of the rings or segments is similar to those of the piston in Firgures 1, 2, 3, 4,
and 6; but it being important in the air pump buckets of steam engines and
in other pump buckets that the waterway should be as large as possible,
the rings or segments require to be as narrow on their resting surface as they
can be conveniently made. In order, therefore, to give them sufficient pres-
sure against the working barrel, an entire metallic ring 0, 0, is placed upon
them, accurately ground and fitted both to the upper surface of the ring of
segments and to the vertical face of the bucket. In lieu of a cover, as repre-
sented for the steam piston, the rings of this bucket are kept from rising by
the four setting screws, p, p, p, p, screwed through the projecting arms of the
brass bars q, q, in which the ends of the bucket lids 1, 1, work, which screws
can be adjusted so as not to press upon the rings, and yet prevent them from
rising out of their place should any dirt or extraneous matter intervene between
them and the barrel.
We do not claim as any part of our Invention the general form of the
steam piston or air-pump bucket herein described. We claim the application
of metallic rings to pistons resting upon inclined planes, or acted upon by
them, and so contrived as to be steam, air, or water tight (in the common
language of engineers) through the simple action of their own gravity, un-
aided by other mechanical forces. We do not limit our claim to the inven-
tion of the three particular pistons herein-before represented and described;
but we have illustrated them as the three best and most efficient modes of
construction on this principle with which we are acquainted.
And we do hereby declare this to be our Specification of our said Invention,
and do verily believe that our said Specification doth comply in all respects with
the proviso in the herein-before in part recited Letters Patent contained.
In witness whereof, we, the said Benjamin Hick, Edward Evans the elder,
and John Higgins, have hereunto set our hands and seals, the Twenty-
ninth day of December, in the year of our Lord One thousand eight
hundred and thirty-four.

page_text: AND BE IT REMEMBERED, that on the Twenty-ninth day of December,
in the fifth year of the reign of His Majesty King William the Fourth, the said
Benjamin Hick, Edward Evans the elder, and John Higgins, came before our
said Lord the King in His Chancery, and acknowledged the Instrument
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Instrument aforesaid was stamped according to
the tenor of the Statute made in the fifty-fifth year of the reign of His late
Majesty King George the Third.