Improvements in Stop and other Valves.
Year: 1895

page_text: Date of Application, 16th July, 1895
Complete Specification Left, 16th Apr., 1896-Accepted, 16th May, 1896
PROVISIONAL SPECIFICATION.
Improvements in Stop and other Valves.
I, ALEXANDER TURNBULL, of the Firm of A. Turnbull and Company, Engineers,
Bishopbriggs, in the County of Lanark, do hereby declare the nature of this invention
to be as follows:-
This invention which relates to stop valves and like valves has for its object to
provide means whereby the liability of the valve spindle to stick or become jammed
by expansion or otherwise when screwed hard down is obviated, and whereby the
valve may be maintained on its seat with a pressure due to any desired load.
To that end I interpose a helical, plate or other spring between a flange or shoulder
formed on the crosshead through which the valve spindle passes and a like flange or
shoulder on a nut or internally screw-threaded sleeve on the screwed portion of the
valve spindle, so that when the valve is screwed close on to its seat, any further
turning of the wheel and valve spindle causes the nut or screwed sleeve to travel along
the spindle and compress the spring. The spring thus resists the opening pressure on
the valve, and the closing pressure may be regulated by more or less compressing the
spring. As a simple expedient for limiting the pressure to be applied on the spring
the end of the nut or sleeve may be carried through the crosshead to such an extent
that the boss of the handwheel or checkwasher will be brought to bear on it when the
desired pressure has been attained.
The invention is applicable not only to conical or flat seated valves but to sluice
valves and other valves operated by a screw spindle, and the spring may be fitted at
any convenient point either inside or outside the valve casing so long as it is arranged
to apply the closing pressure on the valve.
Dated this 15th day of July 1805
..
Improvements in Stop and other Valves.
I, ALEXANDER TURNBULL, of the Firm of A. Turnbull and Company, Engineers,
Bishopbriggs, in the County of Lanark, do hereby declare the nature of this inven
tion and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
This invention which relates to stop valves and like valves has for its object to
provide means whereby the liability of the valve spindle to stick or become jammed
by expansion or otherwise when screwed hard down is obviated, and whereby the
valve may be maintained on its seat with a pressure due to any desired load.
The invention is illustrated by the accompanying drawings, Figure 1 of which is an
elevation partly in section of the improved stop valve and Figure 2 a modification of
the same.
In carrying out the invention as shewn by Fig. 1, 1 interpose a helical, plate or
other spring A between a flange or shoulder B formed on the crosshead C through

page_text: which the valve spindle D passes and a like flange or shoulder E on a nut or internally
screw-threaded sleeve F on the screwed portion of the valve spindle D, so that when
the valve is screwed close on to its seat, any further turning of the wheel G and valve
spindle D causes the nut or screwed sleeve to travel along the spindle and compress
the spring A, a feather f being provided on the sleeve F which engages with a slot
on the flange B of the crosshead C to prevent said sleeve from turning. The
spring A thus resists the opening pressure on the valve, and the closing pressure may
be regulated by more or less compressing the spring. As a simple expedient for
limiting the pressure to be applied on the spring A the end of the nut or sleeve F may
be carried through the crosshead C as shewn to such an extent that the boss of the
hand wheel G or checkwasher H-will-be brought to bear on it when the desired
pressure has been attained.
In the position shewn by the drawings the valve is merely closed down on its seat,
little or no pressure being applied by the spring. By turning the valve spindle D in
the direction for screwing down the valve the sleeve traverses the crosshead and the
spring A is thereby compressed more or less according to the extent of movement of
the sleeve. The checkwasher H on the spindle D limits the extent of traverse of the
sleeve F on the spindle D and therefore the degree of compression which may be
varied by adjusting the position of the checkwasher H. In the event of the spring A
breaking the sleeve F and with it the spindle D can only rise a very short distance
until a shoulder on the sleeve F comes into contact with the flange or shoulder B
on the crosshead C. A nut I is provided on the sleeve F for the purpose of
regulating the initial pressure of the spring A.
In the modification shewn by Fig. 2 the spring A is situated between a shoulder on
the spindle D and the sleeve F said sleeve which is screwed into the crosshead C
being carried through the crosshead and keyed to the handwheel G. A nut I is
provided on the end of the spindle D and bears against the boss of the hand wheel G
for regulating the initial pressure of the spring A. The check washer H on the
sleeve F limits the extent of traverse of the sleeve in the crosshead and therefore
the degree of pressure on the valve and in the event of the spring A breaking, the
spindle D can only rise a short distance until a washer d on the spindle D comes into
contact with the end of the sleeve F, and the handwheel G can then be turned to close
the valve.
The invention is applicable not only to conical or flat seated valves but to sluice
valves and other valves operated by a screw spindle, and the spring A may be fitted
at any convenient point either inside or outside the valve casing so long as it is
arranged to apply the closing pressure on the valve.
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. In a stop valve or other valve the adaptation of a spring or springs to maintain
the valve on its seat with any desired degree of elastic pressure substantially as
described.
2. In a stop valve or other valve the combination with the valve spindle of a spring
interposed between a sleeve movable on said spindle and the stationary crosshead or a
collar on the spindle or other fixture substantially as and for the purpose set forth.
Dated this 15th day of April 1896
WALLACE FAIRWEATHER,
Chartered Patent Agent,
62 Saint Vincent Street, Glasgow, Agent for the Applicant.