IMPROVEMENTS IN PUMP PISTONS.
Year: 1872

page_text: LETTERS PATENT to Charles John Geneste, of Upper Norwood, in the
66
County of Surrey, for the Invention of IMPROVEMENTS IN PUMP
PISTONS.".
Sealed the 7th May 1872, and dated the 24th January 1872.
PROVISIONAL SPECIFICATION left by the said Charles John Geneste
at the Office of the Commissioners of Patents, with his Petition,
on the 24th January 1872.
I, CHARLES JOHN GENESTE, of Upper Norwood, in the County of
Surrey, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN PUMP PISTONS," to be as follows:―
My Invention has for its object the construction of a metal piston to
be worked up and down in a cylinder by means of a chain, rope, or rod,
which piston shall fit the cylinder when moved upwards but which shall
move freely in the cylinder during the downward stroke. For this
purpose I construct the piston of several segments, each of which is
connected to those next it by joints in such a manner that it can oscillate ..

page_text: a little in a vertical direction, and I make each segment of such a form
that the weight of its inner part tends to cant it when that weight is
left free to act. I also make the lower and inner edge of each segment
with a sloping face, and fix on the chain, rope, or rod which works the
piston a collar which bears on this face as the piston is drawn. upwards
and thereby cants back the segments so as to make their periphery fit
the bore of the cylinder. Thus during the down stroke the segments
being canted by the weight of their inner parts are slack in the bore and
move freely therein, but during the up stroke they are made to fit the
bore with sufficient tightness to prevent leakage past the piston.
VI
filed by the said Charles John Geneste in the Great Seal Patent
Office on the 13th May 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
JOHN GENESTE, of Upper Norwood, in the County of Surrey, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fourth day of January, in the
year of our Lord One thousand eight hundred and seventy-two, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Charles John Geneste, Her special
licence that. I, the said Charles John Geneste, my executors, admi-
nistrators, and assigns, or such others as I, the said Charles John
Geneste, 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 PUMP PISTONS," upon the condition (amongst others)
that I, the said Charles John Geneste, 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,.
"

page_text: 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 Charles John Geneste, 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, reference being had to the accompanying
Sheet of Drawings, and to the figures and letters marked thereon, that
is to say:
My Invention has for its object the construction of a metal piston to
be worked up and down in a cylinder by means of a chain, rope, or rod,
which piston shall fit the cylinder when moved upwards but which shall
move freely in the cylinder during the downward stroke. For this
purpose I construct the piston of several segments, each of which is
connected to those next it by joints in such a manner that it can oscillate
a little in a vertical direction, and I make each segment of such a form
that the weight of its inner part tends to cant it when the weight is left
free to act. also make the lower and inner edge of each segment with
a sloping face, and fix on the chain, rope, or rod which works the piston a
collar which bears on this face as the piston is drawn upwards and
thereby cants back the segments so as to make their periphery fit the
bore of the cylinder. Thus during the down stroke the segments being
canted by the weight of their inner parts are slack in the bore and move
freely therein, but during the up stroke they are made to fit the bore
with sufficient tightness to prevent leakage past the piston.
Fig. 1 represents a plan, and Fig. 2 a section on the line ¼, ½, of a
pump piston constructed according to my Invention. One half of the
plan, Fig. 1, is represented with the caoutchouc or leather valve removed
to show the construction below it.
A is the rod of the piston, which may either be continued upwards
as a rod to the crank or beam which gives it reciprocating motion,'or
may be hung by a rope or chain, the piston being pulled upwards thereby
for the up stroke, and being allowed to descend by its own weight for the
down stroke. B is a tapered boss fixed on the lower end of the rod A;

page_text: '
and C, C, are segments into which the piston is divided. Each segment
has an inclined base, which rests on the boss B, and each pair of adjoining
segments is mounted on a bent bar D, the ends of which form trunnions
on which the segments oscillate, the segments being held to the cylin-
drical parts of the bars D by clip pieces E fixed to the segments. There
are spaces. F left between each pair of segments to allow of their
approaching each other when they are canted; and passages G are
formed through each segment for the flow of water through them when
the piston descends. These spaces and passages are covered by a
caoutchouc or leather disc H, which acts as a valve to prevent water
passing the piston when it ascends. The disc H is formed with an exte-
rior lip H', which is pressed against the interior surface of the barrel as
the piston ascends; and it is made with a tubular boss H2 in the middle,
which boss embraces the rod A and is secured in a hollow in the rod by
wire or twine being wound tightly round it. The disc H has openings I
cut through it to permit of its folding upwards, and to give passage for
water through it as the piston descends. A plate of metal K is rivetted
'to the disc over each of the spaces between the segments to prevent the
caoutchouc from being bulged downwards into these spaces by the pres-
sure above it as the piston ascends. In order to prevent the segments C
from turning round relatively to the disc H the boss B is made with
ribs B projecting into grooves formed in the bases of the segments.
From this construction it will be seen that the piston in its up stroke
fits the cylinder, but that in the down stroke the segments are canted
and the caoutchouc is bent upwards (as indicated by the dotted lines at
C¹ and H³ on one side of Fig. 2) so that the piston is loose in the cylinder
and can descend therein by its own weight, the water below it flowing
through the spaces between and passages in the segments and past the
edge of the disc H and the edges of the apertures I in the disc. The
number of segments may be varied, and also the construction of the
covering disc or valve, and generally the details and proportions of the
parts may be modified without departing from the principle of my
Invention. Also, though it is preferred that the segments should be of
such form and jointed at such places that during the descent of the
piston the weight of the inner part of each segment should by over
balancing that of the outer part assist in canting it into the position
suited for free descent, this is not absolutely necessary, because the
pressure of the water through which the piston descends acting on the

page_text: larger area of each segment outside its joint or pivot has an equivalent
effect in canting the segment.
Having thus described the nature of my Invention, and in what
manner the same is to be performed, I claim; the use of a pump piston
consisting of several segments connected together by joints and bearing
on a sloping base so that they may oscillate in such a manner that the
piston is made to fit the cylinder in ascending but that it can descend
freely, substantially as herein described.
In witness whereof, I, the said Charles John Geneste, have here-
unto set my hand and seal, this Twenty-ninth day of April, in
the year of our Lord One thousand eight hundred and seventy-two.
CHARLES JOHN GENESTE. (L.S.)