IMPROVEMENTS IN THE PACKINGS OF PISTONS AND PISTON RODS OF PUMPS AND STEAM AND OTHER ENGINES, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO HYDRAULIC PRESSES
Year: 1865

page_text: LETTERS PATENT to William Robert Foster, of Cowper Street, City
Road, in the County of Middlesex, India-rubber Manufacturer, for the
Invention of "IMPROVEMENTS IN THE PACKINGS OF PISTONS AND PISTON RODS
OF PUMPS AND STEAM AND OTHER ENGINES, WHICH IMPROVEMENTS ARE ALSO
APPLICABLE TO HYDRAULIC PRESSES."
Sealed the 21st March 1865, and dated the 18th January 1865.
PROVISIONAL SPECIFICATION left by the said William Robert Foster
at the Office of the Commissioners of Patents, with his Petition, on the
18th January 1865..
I, WILLIAM ROBERT FOSTER, of Cowper Street, City Road, in the County
of Middlesex, India-rubber Manufacturer, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE PACKINGS OF PISTONS AND PISTON
RODS OF PUMPS AND STEAM AND OTHER ENGINES, WHICH IMPROVEMENTS ARE ALSO
APPLICABLE TO HYDRAULIC PRESSES," to be as follows:
My improvements in packings for stuffing-boxes or other purposes consist
in the application of a coil of india-rubber tube around the rod in the stuffing
box, and compressed therein somewhat in the usual manner. This tube (in
the stuffing-box of a steam engine piston rod, for instance,) I leave open
at the inner end, but close it at the upper or outer end next the gland, so that
the steam may enter within the stuffing tube, which will therefore be subject
to the same pressure internally and externally, and will make the passage of
the rod through it steam-tight. I use vulcanized india-rubber tube of round,
oval, or other form, in cross section, and use a sufficient length to coil round
the rod several times. This packing, when compressed slightly by the packing

page_text: .
gland, will compress the coils to the form of the box and around the rod,
whereby it is rendered tight, and this with very slight pressure of the gland,
and therefore producing very little friction on the rod in working through it.
The tube so used may be covered, or in layers, with canvas, or braided
externally with hemp or other fibrous material, to offer a suitable surface for
the friction of the rod, or to protect the rubber. Instead of india-rubber tube
other elastic or flexible tubing may be similarly employed, being left open at
one end for the admission of the fluid pressure, whose escape it is desirable to
prevent.
This packing is applicable for stuffing-boxes, or as a packing for pistons, in
which case, when the fluid pressure is on both sides of the piston, I leave both
ends of the tube open for its admission to the interior of the tube, but provide
a stop in the middle of its length, that is to say, at a point two or three coils
distant from each end. It is also applicable for air, water, and other pumps,
and in hydraulic presses, to retain the pressure of the fluid round the ram,
where it emerges from the cylinder.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Robert Foster in the Great Seal Patent Office on
the 18th July 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT FOSTER, of Cowper Street, City Road, in the County of Middlesex,
India-rubber Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of January, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Robert Foster, Her special licence that I, the said William Robert
Foster, my executors, administrators, and assigns, or such others as I, the said
William Robert Foster, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times there-
after 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 PACKINGS OF PISTONS AND PISTON RODS OF PUMPS, AND STEAM AND OTHER
ENGINES, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO HYDRAULIC PRESSES,"
upon the condition (amongst others) that I, the said William Robert Foster,
I

page_text: 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 per-
formed, 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 William Robert Foster, do hereby
declare the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say) :-
The friction caused by the packing in the stuffing box of a steam engine
with the most improved packings is usually an endless source of complaint,
causing a great loss of power and waste of lubricating material. Many attempts
have been made to remedy these defects, that is to say, to reduce the friction,
economize the material, and prevent the escape of steam, but hitherto, I
believe, without success.
The object of my Invention is to effectually reduce the friction attendant
on these packings, and at same time provide against the escape or passage of
fluid.
To accomplish this I use a hollow or tubular packing in one or more rings
or coils, open at one end and closed at the other, so that the steam, gas, air,
or fluids shall enter the packing, and with the elasticity of the packing and
pressure of the cover or gland, make a piston rod or any description of packed
rod perfectly tight.
My improvements in packings for stuffing boxes and other purposes thus
consist in the application of a coil or rings of india-rubber tube around the
rod in the stuffing box, and compressed therein somewhat in the usual manner
of compressing the packing of stuffing boxes. The tube in the stuffing box of
a steam engine piston rod, for instance, I leave open at the inner end, but
close it at the upper or outer end next the gland, so that the steam may enter
within this stuffing box tube, which is therefore subject to the same pressure
internally and externally, and will cause the passage for the rod through it to
.be steam-tight. I use vulcanized india-rubber tube of round, oval, or other
form, in cross section, and apply sufficient length of tube to coil round the rod
several times. This packing, when compressed slightly by the packing gland,
will compress the coils somewhat to the form of the box and around the rod,
whereby it is rendered tight, and this with very slight pressure of the gland,
therefore producing very little friction on the rod in working through it. The

page_text: tube so used may be covered in layers with canvas, or braided externally with
one or more layers of hemp, cotton, or other fibrous material, to offer a suit-
able surface for the friction of the rod to protect the india-rubber. Instead of
india-rubber tube, other elastic or flexible tubing may be similarly employed,
but in all cases left open at one end for the admission of the fluid under
pressure, whose escape it is desired to prevent.
This packing is applicable for stuffing boxes, or as a packing for pistons,. in
which case, where the fluid pressure is on both sides of the piston, I leave
both ends of the tube open for its admission to the interior of the tube, but
provide a stop in the middle of the length of the tube, that is to say, at a
point two or three coils distant from either end. It is applicable for: steam,
air, water, or other pressure, and for air and other pumps, also to hydraulic
presses, to retain the pressure of the fluid round the ram, where it emerges
represents a section
a stump
& Stea
nder
with the piston rod A passing through the stuffing box- fitted and furnished
according to my Invention; B, B, is the stuffing box; C, C, the gland; and
D, D, the hollow coil disposed in the stuffing box, and compressed although
slightly by the gland C.
Fig. 2 is a cross section, while Fig. 3 represents a partial external view
of the tube used in the stuffing box, which Figure also is continued in
partial longitudinal section. This tube is simply a piece of vulcanized india-
rubber tubing e, e, the manufacture of which is well understood, and need
not be bere described. This I prefer to coat or cover with threads of fibrous
material to the extent of three or four thicknesses, which I apply loosely,
so as to produce a soft and pliant surface, suitable for the wear and friction
of the rod A. In the one end of the tube D I place a plug g, Fig. 1, and
secure it therein by binding on the exterior or otherwise, while in the other
end, and preferably throughout the length of tube D, I place a coil wire
tube h covered with cotton, or it may be a plain helix or coil of wire. This
is placed loosely within the tube D, and keeps the desired end and throughout
its length open for the entrance of the steam or other fluid under pressure.
The packing tube so furnished is placed and coiled within the stuffing box, as
seen, the gland being bolted and screwed down as usual, but with scarcely
any pressure upon the packing. By thus fitting and applying the packing the
steam in the cylinder F always finds access to the tube D, which it expands,
and forms a steam-tight packing for the passage of the piston rod A.

page_text: In Fig. 1 I have also represented this packing applied to a piston H. It
is arranged and furnished in same manner as for a stuffing box; but for a
piston, the pressure being alternately on one side and the other, I make the
packing tube in duplicate, so to speak, that is to say, open at both ends, with
a plug or stoppage i in the middle of its length. Thus as the pressure of
steam alternates on one side or the other the steam enters the tube from
either end, and so renders the packing tight by its pressure within the tube,
and maintaining the external pressure of the packing to render the piston at
all times steam-tight in the cylinder while working, and this with the least
possible amount of pressure and friction, which is, moreover, always uniform.
Fig. 4 represents a section of an hydraulic press cylinder furnished with
my improved packing, which is fitted and applied in same manner as in the
stuffing box of the piston rod, and will not require any particular description.
It will be readily understood from these illustrations that this packing may
be applied in stuffing boxes of pump rods, and as packings for the pistons,
plungers, or buckets, and generally where analogous packings are used, but
which applications will be obvious from the foregoing illustrations, and need
not be individually or more particularly described.
Having described the nature of my Invention, and the manner of per-
forming the same, I declare that what I claim as my Invention to be
protected by the herein-before in part recited Letters Patent is, the applica-
tion of a flexible tube or tubes as packing in stuffing boxes and other similar
adaptations, having the end or ends of such tube or tubes open and exposed
to receive the pressure of the fluid, as and for the purposes herein-before
described.
In witness whereof, I, the said William Robert Foster, have hereunto set
my hand and seal, this Seventeenth day of July, in the year of our
Lord One thousand eight hundred and sixty-five.
Witness,
W. CLARK,
Patent Agent,
53, Chancery Lane,
London.
W. R. FOSTER. (LS.)