Year: 1886

page_text: I, WILLIAM LOCKHART BONE of 120ª Oxford Street, Manchester in the County
of Lancaster, Mechanical Engineer 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:-
My invention relates to spring safety valves for controlling or limiting the
pressure of steam in boilers and for other similar purposes and consists in improve-
ments in the combination, construction or arrangement of the said valves or. their
parts which make it impossible for the attendant to alter the pressure of the spring
on the valve while in use and at the same time enable him to ease or raise the
valve from its seat or turn it on its seat when required.
The drawing appended hereunto shows a valve constructed or arranged on my
improved plan, figure 1 showing a vertical section, figure 2 an outside view and
figure 3 a top view of the same. Similar letters of reference denote similar parts
in the different figures.
The valve casing a is preferably formed with threads band a hexagon c on it
near the top end and screwed into a seating d rivetted to the boiler, but may
instead thereof be formed with a flange for bolting it to a seating or to the boiler
shell. The lower part of the casing projects into the steam space of the boiler and
is provided with openings e for the admission and passage of the steam from the
boiler to the underside of the valve f. The bottom g of the casing forms an
abutment for the spring h and is cast with a tube i perforated for the passage of
the spindle k., The spindle is screwed into or otherwise fixed to the valve ƒ and
has at its lower end a nut / screwed upon it with a tray or washer m forming the
other abutment for the spring h, which latter is compressed and adjusted by means
of the nut L. The spring is preferably made helical and of square wire of steel or
other suitable material, but a helical spring made of round wire or a volute spring
may be used instead thereof.
The seat and the lip may be arranged or shaped in any usual manner but are
made in all cases so that an increased area beyond the internal area of the valve
seating is presented to the action of the escaping steam when the valve is lifted
for the purpose of overcoming the increasing resistance of the spring. The
action of the valve under steam pressure is similar to those made on
"Adams
system."

page_text: In order to enable the attendant to turn the valve and to ease or lift it off its
seat when required a collar n is formed or fixed upon the spindle k the lower side
of which is not at right angles to the axis of the spindle but inclined thereto as
shewn on figure 1, and on the bottom g of the casing a boss o is cast on underneath
the collar inclined to the axis of the spindle or casing at the same angle as the
underside of the collar. If the inclined faces of the boss and the collar are in the
position shewn on figure 1, they are parallel and distant from each other by
the thirty second part of an inch or thereabouts, but when the spindle is turned
round, the inclined surfaces come upon each other and the spindle k with the
valve is thereby lifted. A bexagon projection p cast upon the top of the
valve f to which a screw key can be applied and the valve turned round upon its
seat and lifted or eased by a distance determined by the angle the underside of the
collar n and the boss o form with the axis of the spindle. By this arrangement
steam can be blown off at or below the ordinary working pressure and the discharge
stopped immediately by turning the valve round till the underside of the collar n
and the boss o are out of contact with each other.
After the desired compression has been put upon the spring by means of the
nuta split pin q or its equivalent is put through the nut and valve spindle to
prevent the nut being turned on the spindle by the action of turning the valve
and spindle round and the compression of the spring being increased or reduced
thereby.
It is obvious that the valve instead of being fixed upon a seating on the boiler,
may also be fixed upon a pipe, vessel or chamber in open communication with the
steam space of the boiler.
As the lower part of the valve casing is within the steam space, it is impossible
for the attendant to alter the compression of the spring while the boiler is at work.
To prevent the compression being altered when the valve is removed from the
boiler, a solid pin with a head at one end and a hole in the other is in some cases
used instead of the split pin g and a padlock or plumbed wire passed through
the hole.
Having now particularly ascertained the nature of my invention and in what
manner the same is to be performed, I declare that what I claim is
Firstly, the general construction and arrangements of parts forming a spring
safety valve, substantially as described and illustrated.
Secondly the arrangements for turning and easing or raising the valve sub-
stantially as described and illustrated.
Dated the 10th day of Tule 1886