An Improvement in Stop Taps for Preventing Water Pipes from Bursting.
Year: 1895

page_text: Date of Application, 23rd Mar., 1895
Complete Specification Left, 23rd Dec., 1895-Accepted, 21st Mar., 1896
PROVISIONAL SPECIFICATION.
An Improvement in Stop Taps for Preventing Water Pipes from
Bursting.
WILLIAM DODWELL 59 Radnor Street Chelsea in the County of Middlesex
Plumber do hereby declare the nature of this invention to be as follows:-
An improvement in stop taps fitted with two valves with reverse threads for
stopping the supply of water from companies' main and at the same time emptying
rising main to building.
The body of this screwed down stop tap (sometimes termed a stop cock or stop
valve) is cast with two grooves for the top valve to work in and faced seating for
top valve to seat on. It has two grooves for the bottom valve to work in, also a
It has a female
waste outlet at the bottom faced for the bottom valve to seat on.
thread at the top for the male thread of the top of tap to screw into.
The top of the tap or cock is made so that the top or main valve may work up
into it when the main is on, and thus give it as much waterway as possible.
A shoulder is left on about half way from the top for collar ou spindle to turn and
work on, which is held down by the packing and stuffing box cap; it has also a
male thread to screw into the body of the cock.
The main or top valve which stops the supply from companies' main is cast
with two slides for working up and down the grooves in the body of the cock, and
is made with a left-handed thread, and a stuffing box, also fitted with washer so as
to keep the valve water-tight when screwed down.
The bottom or waste valve which is for emptying the pipes is cast with two
slides for working up and down the grooves in the body of the cock, and is made
with a right handed thread, and fitted with washers for regulating it.
The spindle is fitted with a crutch at the top for turning it with, also with a
loose collar pinned on after the top or main valve has been put into its place.
It is fitted with a corresponding thread to each valve namely a felt handed thread
for the top valve and a right handed thread for the bottom valve.
The idea of this improved screwed down stop tap is to stop the supply from
companies' main, and at the same time completely empty the rising main to
building. The action of this stop tap can now be clearly seen by the reverse
threads of the valves worked by the spindle held in position by the collar in the
top of tap and held down by the stuffing box cap, and both valves held by their
respective slides & grooves in the body:
Dated this 2nd day of April 1895.

page_text: An Improvement in Stop Taps for Preventing Water Pipes from
Bursting.
I, WILLIAM DODWELL 59 Radnor Street Chelsea in the County of Middlesex
Plumber 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 :-
The body of this screwed down stop tap sometimes termed a stop cock or valve
is cast with two grooves for the top valve to work in and faced seating for same to
seat on. It has two grooves or slides for the bottom valve to work in, also a waste
outlet at bottom, faced and ground for bottom valve to be regulated. It has a
female thread at the top for the top of tap to screw into. The top of the tap is
made so that the top or main valve may work up into it when the main is on and
thus give it as much water way as possible, a shoulder is left on about half way
from the top for collar on spindle to turn and work on; which is held down
by the packing and stuffing box cap. It has a male thread to screw into body
of cap.
The main or top valve which stops the supply from the company's main is
cast with two slides for working up and down the grooves in the body of cock and
is made with a right handed thread, and fitted with stuffing boxes and washed so
as to keep the valve watertight when screwed down.
The bottom or waste valve which is for emptying the pipes is cast with two
slides or grooves for working up and down the prepared parts in body of cock and
is made with a left handed thread and fitted with washers for regulating it.
The spindle is fitted with a crutch at the top for turning it with; also a collar
screwed or pinned on after the top valve is put into its place. It is fitted with
corresponding threads to each valve viz., left handed for the top and right handed
for the bottom valve.
The idea of this improved screw down stop cock is to stop the supply from the
main and at the same time completely draining the rising main from the building
to the stop cock, thus preventing the said water pipes from freezing & bursting.
Referring to the annexed drawings
Figure 1 is a sectional side elevation of a tap constructed according to my
invention.
a is the spindle having the collar 6 attached to same in any convenient manner.
c is a valve carried upon a screw thread f upon said spindle, for closing the
seating d. e is a valve also carried upon a screw thread g upon the spindle a, said
valve e closing the aperture h terminating in the nozzle i to which a pipe may. be
attached.
The screw threads ƒ and g are what is known as right & left handed threads so
that when the valve c is closed upon the seating d, the valve e being at the
same time removed from the seating or aperture owing to the spindle having
the two threads thereon namely right and left handed and when the valve c is
removed from its seating the valve e is brought into contact with the seating or
aperture h.
By this arrangement; when the water supply from the main is cut off the water
remaining in the pipes at a greater level than the nozzle i will run off owing to the
valve e being opened, thus preventing the freezing of the water in the pipes above
the point of escape.
The valves cand e are provided with lugs or projections which engage in grooves
in the body of the valve as are generally employed. It will be seen that by
operating or turning the spindle a the valves cand e will be moved in opposite

page_text: directions owing to the difference of the threads upon the spindle one being a right
and the other a left handed thread.
It will be seen that the outlet when emptying the pipes is at the lowest point
in the tap and a piece of pipe may be readily attached to said nozzle to convey the
water from same when emptying the pipes after the supply has been cut off;
the movement of the spindle a raising the valve c and lowering the valve e or
vice versa so that when the valve e is closed the valve c is open thus allowing the
water to flow to the supply pipes of the house and when the valve c is closed the
If desired I may employ a
water in the supply pipes escapes through the valve e.
spindle having threads of different pitch upon which the valves are carried so that
when the spindle is rotated one valve is closed and the other opened.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The improved stop tap as shewn and described herein.
2. In combination with stop taps, a spindle having two screw threads upon same
one left and the other right handed said screw threads carrying valves, one valve
controlling the supply of water; and the other valve allowing the water in the
service pipes of the house to escape when the supply valve is closed owing to the
screw threads upon the spindle being in opposite directions so that the rotation of
the spindle opens one valve and closes the other.
3. In combination with stop valves, a spindle having two threads of different
pitch upon which valves are carried so that one valve is opened when the other is
closed and vice versa.
1
omba 1805
E. EATON,
Agent for Applicant.