Year: 1887

page_text: RES
Date of Application, 16th Dec., 1887
Complete Specification Left, 14th Sept., 1888
Complete Specification Accepted, 19th Oct., 1888
JOHN EDWARD SLACK 1 Dearnley Terrace, St. Marys Road Moston, Newton
Heath, near Manchester, Draughtsman I do hereby declare the nature of this invention
to be as follows:-
As shown on the drawing accompanying this specification, the arrangement consists
of a lever of wrought or cast iron of some 30 inches in length, from one end of
which is suspended a tile float weighing 50, 60, or 70 lbs., and at the other end is fixed
a brass ball.
To counterbalance the tile float when immersed in water, is suspended from the
same distance from the centre of the lever iowards the opposite end a tile float
weighing 25, 30 or 35 lbs.
Into the brass ball is screwed a rod having a brass cap pinned to it at the
bottom.
a branch from it which is
Surrounding this rod & cap, is a brass casing having
connected to some wrought iron piping leading outside one of the seatings on the top
of the boiler to a steam whistle.
The aforesaid brass casing is grooved at the top to receive the brass ball attached
to the lever.
When the water is lowering and has reached the top of the tile float A, it (the
float) gains weight and descends, causing the lever to raise the brass ball, when steam
escapes to the whistle.
Should the water gain height in the boiler and reach the tile float B, it (the float)
will lose part of its weight and the brass ball be again raised.
The steam can also be led to the furnace of the boiler as well as to the whistle, and
so the fire could be extinguished.
15th December 1887

page_text: COMPLETE SPECIFICATION.
A High and Low Water Alarm Valve for Steam Boilers or
Generators.
JOHN EDWARD SLACK 43 Queens Road, Bowes Park London, N. Draughtsman,
1 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 an improved apparatus which has for its object to improve
the safety of steam boilers or generators in obviating liability to overheating and
consequent explosion.
I also claim by its adoption the production of dry
non aqueous steam.
The nature of this invention will readily be understood by reference to the drawing
left with the provisional specification in which is represented the general arrangement
of the improved apparatus.
The valve proper consists of a circular brass casing in the shape of a T (or other
suitable shape that would answer the same purpose) in connection with which
works a gun metal ball and a small piston, or other steam tight fitting piece, connected
together. This circular brass casing is bevelled at the top end to receive the gun
metal ball, & the area of that part of the ball which is hid by the aforesaid casing is
equal, or nearly so, to the area of the bottom of the piston or other steam tight
fitting piece, which is exposed to the action of the steam in the boiler when at work.
This arrangement equalises the pressure of steam on both the upper and lower part of
the valve.
From the aforesaid brass casing is led away suitable piping (flanged or screwed
to it) to the outside of the boiler or generator, either through the boiler itself or
through one of the mountings on the boiler. On to this piping is fixed as shown a
steam whistle of suitable size.
The valve is worked by the action of tile or other suitable floats having a specific
gravity of about 2 as compared with water.
There are two such floats and they are suspended from a lever, the fulcrum of
which is formed by a suitable leg or stool fixed to the upper part of the boiler.
The heavier and larger float is fixed at one end of the lever, and the small one
between it and the aforesaid valve proper.
These floats are of such sizes that the smaller one about balances the larger one
when the latter is immersed in water.
The brass ball working in connection with the circular brass casing is fixed on
to the aforesaid lever, and when the water in the boiler is at its ordinary working
level or in a given distance of it, the ball fits evenly on the seat of the valve, & it
will not move from that position until the larger float descends, which will be the
case when the water in the boiler sinks beyond the determined limit of safety.
The larger float will also descend when the water in the boiler rises beyond a certain
fixed limit of safety, as the water coming in contact with the smaller float will bear
part of its weight.

page_text: I therefore claim in the event of the water in the boiler or generator rising or
falling beyond a certain fixed distance, & the consequent descent of the larger float
causing the lever to raise the gun metal ball from its seat, that a suitable & sufficient
alarm will be given by the escape of steam through the circular brass casing & piping
to the steam whistle outside the boiler.
I also claim a further advantage by leading a branch pipe from outside the boiler
by means of a T in place of an elbow as shown to the furnace of the boiler. This
branch pipe would have a suitable cock or valve on it near the front of the boiler
and would always remain open, so that in the absence of an attendant the fire
would be put out on the escape of steam, thus ensuring double safety.
Having now particularly described and ascertained the nature of my said Inven-
tion, and in what manner the same is to be performed, 1 declare that what
I claim is :-
―
1st. Each of the combinations of parts forming an alarm valve as shown on drawing
left with provisional specification being novel and original.
2nd. The combination of two floats and a lever to cause the latter to move in
the event of the water in the boiler or generator rising or falling beyond certain
fixed limits.
3rd. The combination of brass valve and lever attachment to same.
4th. Leading the escaping steam through one of the mountings on the boiler or
generator.
5th. Leading the escaping steam if desired to the furnace of the boiler or generator,
so as to put out the fire in the absence of an attendant.
Dated this 14th day of September 1888.
JOHN EDWARD SLACK.