AN IMPROVEMENT IN SCREW STOP VALVES
Year: 1856

page_text: LETTERS PATENT to Charles Durand Gardissal, of 10, Bedford Street,
Strand, London, and of 29, Boulevart St. Martin, Paris, Patent Agent,
for the Invention of "AN IMPROVEMENT IN SCREW STOP VALVES."-A
communication.
Sealed the 5th September 1856, and dated the 29th March 1856.
PROVISIONAL SPECIFICATION left by the said Charles Durand Gardissal
at the Office of the Commissioners of Patents, with his Petition, on the
29th March 1856.
I, CHARLES DURAND GARDISSAL, of 10, Bedford Street, Strand, London, and
of 29, Boulevart St. Martin, Paris, Patent Agent, do hereby declare the
nature of the said Invention for AN IMPROVEMENT IN SCREW STOP VALVES,
to be as follows:-
This Invention relates to a certain construction of the valve and its stem, by
which greater facility is afforded for grinding or repairing the valve than when
constructed in the usual way. The usual construction is to make the screw by
which the valve is opened and closed an immovable part of the valve spindle;
the consequence of which is, that when the valve becomes leaky and requires
to be reground the regrinding is a difficult operation.
This Invention consists in making the screw on a shell, that is attached to
the spindle, in such a way that it can be readily removed to allow of the
grinding of the valve.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Durand Gardissal in the Great Seal Patent Office on
the 26th September 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
DURAND GARDISSAL, of 10, Bedford Street, Strand, London, and of 29,
Boulevart St. Martin, Paris, Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of March, in the year of our Lord
One thousand eight hundred and fifty-six, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Charles Durand Gardissal, Her special licence that I, the said Charles
Durand Gardissal, my executors, administrators, and assigns, or such others as
I, the said Charles Durand Gardissal, 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 "AN IMPROVEMENT IN SCREW STOP VALVES," a communication, upon the
condition (amongst others) that I, the said Charles Durand Gardissal, 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.
NOW KNOW YE, that I, the said Charles Durand Gardissal, 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 & figures marked thereon (that is to say):
This Invention relates to a certain construction of the valve and its stem, by
which greater facility is afforded for grinding in or repairing the valve than
when constructed in the usual way. The usual construction is to make the
screw by which the valve is opened and closed an immovable part of the valve
spindle; the consequence of which is, that when the valve becomes leaky and
requires to be reground the regrinding is a difficult operation.
This Invention consists in making the screw on a shell, that is attache.l to

page_text: the spindle, in such a way that it can be readily removed to allow of the
grinding of the valve.
The Invention is illustrated in the accompanying Drawing, in which Fig. 1
is an outside view, and Fig. 2 a central section, of a valve box and valve; and
Fig. 3 is a view of a valve without the box.
A (Figs. 1 and 2) is the valve box, and B is the valve seat; C is the valve,
having its spindle C* fitted with the movable shell D, on the outer surface of
which is the screw by which the valve is opened and closed, the said screw
fitting to a stationary nut or female screw E in the valve box, in the same
manner as it does when forming an immovable part of the spindle. To secure
the shell D to the valve stem C, a short screw a is cut on the stem, and a
corresponding female screw is cut in the lower part of the shell, which is
screwed tightly down against a shoulder b, provided on the stem, and for further
security a hole is drilled laterally through the shell into the stem, and tapped to
receive a small screw c. To grind the valve in case of its becoming leaky,
unscrew the nut E from the valve box A, to which it is attached by a screw
thread for that purpose, then run the valve down far enough for the screw shell
D to work out of the said nut, draw the screw c & unscrew the shell D from
the screw thread a; now run back the shell D into the nut E, and then replace
the nut in the valve box; the valve c and its stem C* are then free to
revolve without any movement from or towards its seat. The process of
regrinding is to place upon the valve some oil and emery, or some other material,
such as is commonly used for grinding valves, and revolving it in its seat. Tho
cap E of the stuffing box, through which the valve spindle works, keeps the
valve perfectly true during the grinding process without any other appliance.
The valve may either be rigidly attached to its stem, as shown in Fig. 2, or a
loose valve C may be employed, as shown in Fig. 3. This valve is attached
to its stem C by a collar d at the bottom of the stem and a ring e fitting
loosely to the stem and above the said collar, which ring screws into the top of
the valve; a thin metal washer f is placed between the ring and the valve
When it is desired
to prevent the collar & being tightly griped by the valve.
to grind this valve, the nut e is unscrewed, the washer f taken out, the nut e is
then replaced and secured down to the collar d, thereby fixing the valve to
the stem.
Having thus described the nature and particulars of the said improvement
in screw stop valves, I desire it to be distinctly understood that I do not
confine myself to the precise details herein described, as such may be varied
or modified without departing from the principle of action thereof; but I claim

page_text: as new and of our Invention providing the valve spindle with a screwed shell
B, B, applied to the spindle in such a way that it can be removed at pleasure
to grind or repair the valve.
In witness whereof, I, the said Charles Durand Gardissal, have hereunto
set my hand and seal, this Twenty-third day of September, in the year
of our Lord One thousand eight hundred & fifty-six.
C. D. GARDISSAL. (L.S)