Improvements in Draw-off Valves.
Year: 1897

page_text: Improvements in Draw-off Valves.
I, SAMUEL WILKERSON, of Bassingbourn, Cambridgeshire, Engineer, do hereby
declare the nature of this invention to be as follows:-
My Invention relates to improvements in the draw-off valves for which former
Letters Patent were granted to me bearing date the 5th February 1889 No. 2074
and it has more particularly for its object to construct the valve so that leakage may
be avoided either between the valve and its seat when the valve is closed or
through the hinge joint. A further object of my Invention is to provide a valve
which shall be automatically closed when the handle is released.
The draw-off valve described in the Specification of my former Patent consists
of a hinged flap seated over the orifice of the pipe within side cheeks and provided
with a locking lever fulcrumed to a pair of radius links pivoted to the pipe the
radius links being connected to the lever by means of an excentric pin to enable
wear of the joints to be compensated for. Instead of depending on the spring of the
radius link, make the cross bar, which constitutes the axis of the, toggle lever,
itself spring and compensate wear by means of a set screw which bears against
the cross axis.
To enable the hinge joint to be packed without difficulty instead of tightening
the packing from the side as before, the stuffing box is open at the top of the
body portion and closed by a filling piece which is pressed down on top of the
packing. The side cheeks of the valve chamber are united by screws passing
through the one cheek and screwing into the other, one of the screws forming the
pin of the valve. In the prevous valve the motion of the toggle lever was limited
by abutting against the nozzle of the casing but it has been found that the resis-
tance to the pressure of the water on the valve is not so perfect in its action as to
prevent leakage. To avoid this objection the curved face of the valve is prolonged
so as to serve as the stop for the toggle lever. To ensure the automatic closure
of the valve when applied to hydrants and for all purposes when an automatic
closing valve is required a fixed instead of a rotary handle is used, the handle or
extension thereof being caused to act on or compress a spring mounted on the
casing as an abutment which, when the handle is released, closes the valve against
its seat.
In a modified form of valve the side links are done away with and instead of
operating the valve through a toggle motion the handle is pivoted directly on the
back of the valve so that when the valve is in the closed position the handle may
be turned round in position to abut against a flat spring mounted on the casing
whereby the valve is securely held in place.
Datad this 15th day of February 1897.

page_text: I, SAMUEL WILKERSON, of Bassingbourn, in the County of Cambridge, Engineer
do hereby declare the nature of this invention and in what manner the same is to
performed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to improvements in the draw-off valves for which former
Letters Patent were granted to me bearing date the 5th February 1889 No. 2074
and it has mainly for its object to so construct such valves that leakage is avoided
both between the valve and its seat when the valve is closed and through the
hinge joint. A further object of my invention is to provide a valve which shall
be automatically closed when the handle is released.
The draw-off valve described in the specification of my said former Patent con-
sists of a hinged flap seated over the orifice of the pipe within side cheeks and
provided with a locking or toggle lever fulcrummed to a pair of radius links
pivoted to the pipe, the radius links being connected to the lever by means of an
eccentric pin to enable wear of the joints to be compensated for.
depending on the spring of the radius link, I now make the cross bar, by means of
which the toggle lever is fulcrummed to the radius links, itself spring and com-
pensate wear by means of a set screw which bears against the said cross bar.
Instead of
To enable the hinge joint to be packed without difficulty, instead of tightening
the packing from the side as before, I make the stuffing box open at the top of
the body portion and I close it by a filling piece which is pressed down on top of
the packing. The side cheeks of the valve chamber are united by screws passing
through the one cheek and screwing into the other, one of the screws forming the
pin of the valve. In the valve as heretofore made the motion of the toggle lever
was limited by the said lever abutting against the front or nozzle of the casing
but it has been found that with this construction the resistance to the pressure of
the water on the valve is not always sufficient to prevent leakage. To avoid this
objection the front face of the valve is extended so as to serve as the stop for the
toggle lever.
To ensure the automatic closure of the valve when applied to
hydrants and for all purposes when an automatic closing valve is required a fixed
instead of a rotary handle is used, the handle or extension thereof being caused to
act on or compress a spring mounted on the casing, which spring when the handle
15 released, closes the valve against its seat.
To enable my invention to be fully understood I will describe it by reference to
the accompanying drawings, in which:-
Figure 1 is a plan of a draw-off valve having my improvements applied thereto :
Figure 2 is a longitudinal section thereof shewing the valve closed:
Figure 3 is a partial longitudinal section shewing the valve open:
Figure 4 is a view of a detail:
Figure 5 is a side elevation of a self closing draw-off valve having my improve-
ments applied thereto.
a is the flap forming the valve which is faced with packing b and hinged at c
so as to cover the orifice of the pipe d within the side cheeks e, e. f is the locking
lever which is fulcrummed on the radius links g, g and pivoted at h to lugs h¹, h³
on the valve a.
In the valve described in the specification of my former Letters Patent above
named, the necessary spring required when closing the valve was obtained as above
mentioned from the radius links g. I now, however, obtain the said spring by
making the cross bar i which forms the pivot of the lever f, of elastic material
preferably steel. j is the set screw which is screwed through the lever f and

page_text: against the cross bar i, the said set screw being tapered at its end and being
designed to compensate for wear.
The body portion of the valve casing immediately behind the hinge joint. c is
slotted so as to form a recess kopen at the top and into which packing can be
inserted from above, the said packing being pressed down against. the joint by
the filling piece m which is forced into the recess with the necessary pressure by
means of a screw n.
The side cheeks e, e of the valve are united by screws which pass through one
cheek and screw into the other. One of these screws forms the hinge pin c for the
flap valve a and serves to tighten the cheeks e, e, the other screw o uniting the
side cheeks at the front portion thereof. The head of the screw o is formed with a
notch or recess o¹ (see figure 4) which, by turning the said screw, can be brought
opposite a hole in the side cheek of the valve to permit packing q to be inserted.
When the packing is in place the screw is turned into the position shewn so that
the notch in the screw head is not opposite the hole p and the head partially covers
the packing thus securing the latter in the valve.
As above mentioned, the motion of the lever f was heretofore limited by its
abutting against the front of the nozzle of the valve casing thus giving rise to the
disadvantage above described. The front lower end of the valve a is now so
extended, as shewn at a¹, figures 2 and 3, that it acts as a stop for the lever f,
as clearly illustrated in Figure 2.
To limit the upward movement of the lever f, I extend the pin c through the
side cheek e as shewn at c', figure 1, so that it acts as a stop for the radius link g
on that side of the valve.
In figure 5 I have represented a valve which automatically closes when the
lever is released. In this construction the said lever f when being pushed
upwards to open the valve compresses the spring q¹ surrounding a rod r, and
abutting at one end against the said lever and at the other against a stop s upon
the valve. The rod r passes through both lever and stop and is provided at its
front end with a button t which screws on the projecting end of the said rod and
by screwing up which the valve can be set so that it acts as a safety valve and
opens at a predetermined pressure.
With this construction of valve immediately the lever f is released, the spring q¹
closes the valve against its seat.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is:
1. In a draw-off valve of the kind described connecting the locking or toggle
lever to the radius links by means of a spring cross bar provided with a set screw,
substantially as, and for the purposes described and as illustrated in the accom-
panying drawings.
2. In a draw-off valve of the kind described forming a recess behind the flap
hinge, the said recess being designed to receive packing held in position by a
filling piece forced into the said recess by a screw, substantially as described and
as illustrated.
3. In a draw-off valve of the kind described providing the head of the screw e
with a recess or notch o¹ arranged in conjunction with the hole in the valve
casing, substantially as, and for the purpose, hereinbefore described and as
illustrated.
4. In a valve of the kind described extending the front lower portion of the
flap valve a, so as to form a stop a¹ for the toggle lever ƒ, substantially as described
and as illustrated.
5. In a valve of the kind described extending the screw pin c beyond the side
cheek e so as to form a stop to limit the upward movement of the tuggie lever f,
substantially as described and as illustrated.
6. In a valve of the kind described the combination with the toggle lever of a

page_text: spring for automatically closing the valve, and of a screw button for arranging the
valve as a safety valve, substantially as described and illustrated.
7. The combination and arrangement of parts forming the improved draw-off
valves, hereinbefore described and illustrated respectively in figures 1 to 4 and 5
of the accompanying drawings.
1004
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.