IMPROVEMENTS IN SCREW Cocks
Year: 1861

page_text: LETTERS PATENT to Alfred Edwin Carter, of the West Middlesex Water
Works, Kensington, and Thomas Hack, of the West Middlesex Water
Works, Hammersmith, both in the County of Middlesex, for the Inven-
PROVISIONAL SPECIFICATION left by the said Alfred Edwin Carter and
Thomas Hack at the Office of the Commissioners of Patents, with their
Petition, on the 13th November 1861.
We, ALFRED EDWIN CARTER, of the West Middlesex Water Works,
Kensington, and THOMAS HACK, of the West Middlesex Water Works, Ham-
mersmith, both in the County of Middlesex, do hereby declare the nature of
the Invention for "IMPROVEMENTS IN SCREW Cocks," to be as follows:-
This Invention has for its object improvements in screw cocks. In screw
cocks where the valve is actuated by a screw, the stem of which passes through
a stuffing box, it becomes necessary, from time to time to renew the packing
of the stuffing box, and this at present can only be done when the pressure of
the water or other fluid is removed from the cock, as otherwise the water
or fluid would escape around the stem of the screw, and in practice it is
frequently very inconvenient to relieve the valve of the pressure of the
water or fluid for this purpose. To avoid this inconvenience we form a
water-tight joint between the upper surface of the thrust collar on the stem of
the screw and the under side of the cover of the valve box, so that when the
valve is shut down and the upper surface of the thrust collar pressed strongly

page_text: against the under surface of the cover, the escape of water or fluid around the
stem of the screw is prevented, even when the packing is removed. And as this
water-tight joint, in order to be of any service, must be so constructed as to shut
closely, not only when first made, but even after the parts have been long
exposed to the corrosive action of the water or fluid, we let a ring of brass or
other suitable metal into the cover of the valve box around the hole for the
passage of the stem of the screw, and turn the same, by preference, concave.
The thrust collar on the screw (which it is preferred should be of brass) is
turned convex on its upper surface; and it is ground into the ring let into the
cover, as is ordinarily practised in making valve joints. By this arrangement
it is obvious that the packing may be renewed whilst the valve is still exposed
to the pressure of the water or fluid, it being necessary only to shut the valve
closely.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alfred Edwin Carter and Thomas Hack in the Great Seal
Patent Office on the 13th May 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ALFRED
EDWIN CARTER, of the West Middlesex Water Works, Kensington, and
THOMAS HACK, of the West Middlesex Water Works, Hammersmith, both in
the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirteenth day of November, in the year of our Lord
One thousand eight hundred and sixty-one, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Alfred Edwin Carter and Thomas Hack, Her special licence that
we, the said Alfred Edwin Carter and Thomas Hack, our executors,
administrators, and assigns, or such others as we, the said Alfred Edwin
Carter and Thomas Hack, our 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 "IMPROVE-
MENTS IN SCREW COCкs," upon the condition (amongst others) that we, the said
Alfred Edwin Carter and Thomas Hack, our executors or administrators, by an
instrument in writing under our or their hands and seals, or under the hand.
and seal of one of us or them, should particularly describe and ascertain the

page_text: 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 we, the said Alfred Edwin Carter and Thomas
Hack, do hereby declare the nature of the said Invention, and in what
manner the same is; to be performed, to be particularly described and ascer-
tained in and by the following statement thereof, that is to say:-
This Invention has for its object improvements in screw cocks. In screw
cocks where the valve is actuated by a screw, the stem of which passes through
a stuffing box, it becomes necessary from time to time to renew the packing of
the stuffing box, and this at present can only be done when the pressure of the
water or other fluid is removed from the cock, as otherwise the water or fluid
would escape around the stem of the screw, and in practice it is frequently very
inconvenient to relieve the valve of the pressure of the water or fluid for this
purpose. To avoid this inconvenience we form a water-tight joint between
the upper surface of the thrust collar on the stem of the screw and the under
side of the cover of the valve box, so that when the valve is shut down and
the upper surface of the thrust collar pressed strongly against the under surface
of the cover, the escape of water or fluid around the stem of the screw is pre-
vented, even when the packing is removed. And as the water-tight joint; in
order to be of any service must be so constructed as to shut closely, not only
when first made, but even after the parts have been long exposed to the
corrosive action of the water or fluid, we let a ring of brass or other suitable
metal into the cover of the valve box around the hole for the passage of the
stem of the screw, and turn the same, by preference, concave. The thrust
collar on the screw (which it is preferred should be of brass) is turned convex
on its upper surface, and it is ground into the ring let into the cover, as is
.ordinarily practised in making valve joints. By this arrangement it is obvious
that the packing may be renewed whilst the valve is still exposed to the
pressure of the water or fluid, it being necessary only to shut the valve
closely.
And in order that our said Invention may be most fully understood and
readily carried into effect, we will proceed to describe the Drawing hereunto
annexed.

page_text: A is the socket to receive the end of the pipe by which the fluid passes to
the cock, and B is the socket to receive the end of the pipe by which the fluid
passes from the cock; C is the valve; D is the screw, which it is preferred
should be of brass, it works with a nut attached to the valve, as is shewn; E
is the cover of the valve box, in which, as is usual, a stuffing box for the
passage of the stem of the screw D is formed. e is a. brass ring let into the
under side of the cover of the valve box around. the screw; this, it is preferred
to do by making a dovetailed groove in the cover, and expanding a ring of
brass into it; this ring is afterwards bored and turned concave to receive the
thrust collar d on the screw, this collar should be of brass, and we prefer that
the screw itself should be of this metal; the upper surface of this collar is
turned to fit the hollow in the ring e, into which it is then carefully ground.
It is not essential that the ring e should be made concave and the collar d
convex so long as they are fitted and ground together as above described:
Thus when the valve is screwed down hard a perfectly fluid-tight joint is made
between the pieces d, e, this allows of the packing in the stuffing box being
renewed whilst the pipes are charged, which could not otherwise be done
efficiently, as any slight leakage of the valve, or return of the fluid which has
passed the valve, would interfere with the proper packing of the stuffing box.
In witness whereof, we, the said Alfred Edwin Carter and Thomas
Hack, have hereunto set our hands and seals, this Twelfth day of
May, in the year of our Lord One thousand eight hundred and sixty-
THOMAS HACK.
(L.S.)
ALF. E. CARTER. (L.S.)
THOMAS HACK.
(L.S.)
ALF. E. CARTER. (L.S.)