Improvements in or relating to Plug Cocks.
Year: 1899

page_text: Date of Application, 16th Jan., 1899-Accepted, 18th Feb., 1899
COMPLETE SPECIFICATION.
Improvements in or relating to Plug Cocks.
I, LOUIS CLEMENT DAUMAS, of 33, Bedford Gardens, Kensington, in the County,
of London, Doctor of Medicine, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:―
This invention relates to plug cocks specially intended for chemical and other
purposes where great accuracy of fit is required, and has for its object to so
construct the said cocks as to allow, when open, a full passage for fluid, and
also to prevent escape of fluid without having recourse to a stuffing box or
packing material.
According to my invention, the axis of the plug is arranged in an horizontal
position, and the shell or outer case is cast or made in the form of a tube having
flanged ends between which is situated a recess or enlargement containing a
conical plug seating. The plug is conical and is perforated with a hole preferably
of the same diameter as that of the ends of the shell or outer case. The broader
extremity of the plug is provided with a cavity in which is placed a spring which
tends to press the plug to its seat, a plate being preferably interposed between
the said spring and the cover which hermetically closes the recess.
The plug
is also provided circumferentially with teeth so as to form a worm segment with
which gears a screw or worm the spindle of which is suitably journalled in the
shell or case. This screw or worm is provided with a handle whereby it may be
rotated in order to operate the plug, and one end of its spindle which passes
through the shell or outer case is provided with a screw thread of finer pitch
than and in the opposite direction to the aforesaid worm.
This thread engages
with a corresponding thread in the shell or outer case so that when rotated by
the handle the said worm also moves in the direction of its length. Suitable
stops are provided to limit this longitudinal movement of the worm, so that the
plug can be turned through a quarter of a revolution in either direction and thus
be opened or shut as required.
In order that my invention may be clearly understood and readily carried into
effect I will now proceed to describe the same more fully in connection with the
accompanying drawings in which Figure 1 is a vertical section, Figure 2 a
horizontal section and Figure 3 a cross section on line - Figure 2.
A is the outer case or shell, having flanged tubular ends a a, and an enlarged
or recessed part a¹ which forms the plug seat. B is a horizontal conical plug,
the conical part of which is of less length than that of the conical seat a¹ and
which is provided with a cavity band a transverse passage 6 of a diameter not
less than that of the ends a a. C is the cover bolted to the shell for hermetically
enclosing the plug. D is a spring placed in the cavity b and tends to press the
plug B firmly to its seat so as to take up any possible wear and prevent escape of
fluid. E is a plate or washer situated between the cover C and spring D. ee are
studs or pegs fixed in the plug B and passing through the plate E. The plate
E is held in position by these studs e upon which it is free to slide.

page_text: FF are teeth forming a worm segment on the plug B, and F¹ is a worm
gearing therewith. The spindle FX carrying the worm F, has one of its ends
journalled so as to be capable of sliding longitudinally in the casing and has
formed on its opposite end which passes through the casing, a screw thread in
the opposite direction to and of finer pitch than the worm F", which gears with
a corresponding thread in the casing. f, f¹ are stops fixed to the spindle F for
limiting its longitudinal movement, and G is the operating handle.
Upon turning the handle G rotary movement is imparted to the plug B through
the worm F and the worm segment F, and at the same time the worm F¹ is
moved in the direction of its length by means of the fine screw thread f; the
stops being so arranged with respect to the casing against which they
respectively abut when the plug B is in its extreme positions, that the said plug
can be thus moved through a quarter revolution only, in either direction, accord-
ingly as it is required to open or close the cock.
These stops also assist in preventing the passage of fluid past the screw
spindle.
The advantages accruing from the use of this cock are, that a clear passage
equal to the full diameter of the casing is obtained when the plug is open, the
possibility of the escape of fluid is reduced to a minimum owing to the fact that
the spring D always tends to press the plug firmly to its seat and that even
should a small leakage through the plug by any possibility occur an escape to
the atmosphere would be still further resisted by the fine screw thread f and
the outer stop f¹. The cocks may be coated with suitable material to resist
corrosion.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1. A cock having a horizontal conical plug provided with a spring arranged
substantially as described, for the purpose specified.
2. A plug cock having an operating worm which gears with a worm segment
on the plug and which is capable of a limited movement in the direction of its
length, for the purpose specified.
3. A plug cock arranged, constructed and operating substantially as described
with reference to the accompanying drawings, for the purpose specified.
Dated this 16th day of January 1899.
HASELTINE, LAKE, & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.