IMPROVEMENTS IN PACKING FOR STEAM ENGINES, PUMPS, AND OTHER MACHINERY
Year: 1864

page_text: LETTERS PATENT to Henry Attwood, of Wapping Wall, Shadwell, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN PACKING
FOR STEAM ENGINES, PUMPS, AND OTHER MACHINERY."
Sealed the 12th July 1864, and dated the 18th January 1864.
PROVISIONAL SPECIFICATION left by the said Henry Attwood at the
Office of the Commissioners of Patents, with his Petition, on the 18th
January 1864.
I, HENRY ATTWOOD, of Wapping Wall, Shadwell, in the County of
Middlesex, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN PACKING FOR STEAM ENGINES, PUMPS, AND OTHER MACHINERY," to be as
follows:-
This Invention has for its object improvements in packing for steam
engines, pumps, and other machinery. It is well known to engineers that
good hemp, flax, or cotton packing combined with an elastic core makes an
excellent packing, and the elastic core takes much of the friction off the rods
and parts. The best material for the elastic core is india-rubber, but hitherto
the objection to this material has been that the greasy solution or compound
in which hemp, flax, or cotton packing is steeped is found to decompose the.
india-rubber core.
Now, according to my Invention, I protect the core from the influence of this
fatty matter by means of an insulating material interposed between the core.

page_text: and the greased flax, hemp, or cotton. I insulate the core by plaiting around
it a fabric saturated with tar or similar material, or I cover the core with
tarred or prepared twine, or with a veneer of cork, or other material may
be interposed between the india-rubber and the greasy fibre to keep the grease
from contact with the india-rubber. When the core is insulated I then plait
or wind hemp, flax, or cotton around it, so as to make up a packing of any
desired size, this I do by hand or by machinery. The external plate is then
saturated with any greasy composition that may be suitable for the part or
parts to be packed, and it is afterwards pressed to any shape that may be
required. In some cases I substitute for the core of india-rubber one of cork,
as this material is not injuriously affected by grease.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Attwood in the Great Seal Patent Office on the
18th July 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
ATTWOOD, of Wapping Wall, Shadwell, in the County of Middlesex, 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 thousand eight hundred and sixty-four, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Henry Attwood, Her special licence that J, the said Henry
Attwood, my executors, administrators, and assigns, or such others as I,
the said Henry Attwood, 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 "IMPROVE-
MENTS IN PACKING FOR STEAM ENGINES, PUMPS, AND OTHER MACHINERY," upon the
condition (amongst others) that I, the said Henry Attwood, 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, 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.

page_text: NOW KNOW YE, that I, the said Henry Attwood, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
This Invention has for its object improvements in packing for steam engines,
pumps and other machinery. It is well known to engineers that good hemp,
flax, or cotton packing combined with an elastic core makes an excellent
packing, and the elastic core takes much of the friction off the rods and parts.
The best material for the elastic core is india-rubber, but hitherto the objec-
tion to this material has been that the greasy solution or compound in which
hemp, flax, or cotton packing is steeped is found to decompose the india-
rubber core.
Now, according to my Invention, I protect the core from the influence of
this fatty matter by means of an insulating material interposed between the
core and the greased flax, hemp, or cotton. I insulate the core by plaiting
around it a fabric saturated with tar or similar material, or I cover the core
with tarred or prepared twine, or with a veneer of cork, or other material may
be interposed between the india-rubber and the greasy fibre to keep the
grease from contact with the india-rubber. I prefer to braid or cover the
core with twine saturated with tar, the tar having a small proportion of tallow
mixed with it to soften it, say 8 parts of tar to one part of tallow, but in place
of twine a narrow fabric may be employed as before stated, and the twine or
fabric may be saturated with any other material suitable for preventing grease
passing to the inside core of india-rubber. When cork is employed for covering
the core, the cork is cut into long narrow strips by cutting strips spirally
from a block of cork, and these strips are wound around the india-rubber
core, and are cemented to it with suitable cement, say, shellac dissolved in spirit.
When the core is thus insulated I plait or wind hemp, flax, or cotton around
it, so as to make up a packing of any desired size, this I do by hand or by
machinery as is well understood. The external plait is then saturated with
any greasy composition that may be suitable for the part or parts to be
packed.
I use generally by preference a mixture of French chalk and tallow in
the proportion of one part of French chalk to four parts of tallow, the
packing is afterwards pressed to any shape that may be required, and this I
do by passing it through grooved rollers, the grooves being either of a circular
or square form according as a circular or square packing is required, the
packing is also consolidated by being passed through the rollers. In some
cases substitute for the core of india-rubber one of cork, as this material is.

page_text: not injuriously affected by grease. When using a core of cork the cork may
at once be covered with a coating of hemp, flax, or cotton saturated with a
greasy composition without the core being first surrounded by an insulating
material.
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 exact details described, but what I claim in making packing
for steam engines, pumps, and other machinery is,-
First, the interposing an insulating material such as tarred twine or a
veneer of cork between a core of india-rubber and the greasy fibre or yarn
with which it is surrounded.
Second, I claim the employment in making packing of a core of cork
surrounded with greasy fibre or yarn.
In witness whereof, I, the said Henry Attwood, have hereunto set my
hand and seal, this Eighteenth day of July, in the year of our Lord
One thousand eight hundred and sixty-four.
HENRY ATTWOOD. (L.S.)