An Improved Safety Valve for Steam Boilers.
Year: 1898

page_text: Date of Application, 3rd June, 1898-Accepted, 9th July, 1898
COMPLETE SPECIFICATION.
An Improved Safety Valve for Steam Boilers.
I, LOUIS SCHNEIDER, of 7, Fazolochberg, Magdeburg, in the German Empire,
Royal 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 improvements in safety valves for steam boilers, and
has for its object, to prevent the possibility of such valve being tampered with for
the purpose of obtaining a greater or higher steam pressure than that for which
the boiler is registered, the said valve being so constructed and enclosed as to
render it impossible for the attendant or other persons to introduce thereinto
any foreign body or substance that could interfere with the working of same.
In order that my invention and the manner of its use may be fully understood
reference is hereinafter made to the accompanying drawings, of which,
Fig. 1 is a vertical central section of my invention with the piston and stem
thereof only partly in section.
Fig. 2 is a vertical central section of Fig. 1.
Fig. 3 is a plan view partly in section upon the line A B Fig. 2.
Fig. 4 is a section somewhat similar to Fig. 1 but illustrating an alternate
method of construction.
My invention consists of a piston having a hollow tapered or cone-shaped stem A,
and a suitably packed head B, the latter being adapted to slide vertically within
a steam tight guide C, in fixed connection with a casing D, between which and
the stem A is a space or steam passage E, which opens out into an exhaust
passage F', the said casing being formed integrally with an outer jacket G, adapted
to form a cover G, which serves as an enclosing canopy for the casing D and
arranged to form steam passages H and Hat either side of the said casing, and
in combination therewith a flange J, having suitable bolt holes, through which,
and an intervening metallic or other plate or block K, pass suitable bolts L by
means of which the whole may be connected to the upper part of the boiler (repre-
sented by a dotted line in Figs. 1, 2 and 4).
The said plate or block K has in its under surface a preferably oblong chamber M,
adapted to coincide with a like shaped hole in the boiler, so that steam from the
boiler may enter and fill the said chamber, the said plate or block having in its
upper surface a circular hole communicating with the chamber M, and in the said
hole slides vertically, guides a, connected to or formed integrally with the lower
end of the stem A, the said guides being also in fixed connection, with a pin or
rod N connected to or formed with and depending from the lower and solid end
of A, the said lower end of A and the said guides a also carrying a rim or flange O,
which forms a valve seated upon the upper surface at of the plate or block K, the
said plate or block having passages b, which form steam conduits from the
chamber M to the passages H and H¹.
The said plate or block K is constructed to carry a shaft P, one end of which is
carried in a bearings c while its opposite end is carried in a suitable stuffing box
or packed gland d. The said shaft P passes through the chamber M, and thercat
carries a cam e adapted to collide with the pin or rod N depending from A when

page_text: the upper and smaller end or piston head of the said stem or rod, the lower and
larger end of the latter being adapted to form a valve resting upon a suitable seat-
ing open to the boiler, the said valve when raised opening a steam passage from
the boiler to a suitable exhaust, the said piston and its accessories being provided
with means for adjusting their combined weight, such weight being governed by
a calculation of the steam pressure and the difference in the cross sectional areas
of the lower and upper ends of the said piston substantially as and for the pur-
poses stated and shewn by the accompanying drawings.
2nd. A safety valve for steam boilers characterized by the claim and consist-
ing of a hollow tapered or cone shaped stem or rod such as A, having a suitably
packed head or piston B, and a lower end or valve such as O, the latter resting
upon a scating such as a¹ and of larger superficial area than 13, and both adapted
to slide vertically by the means of suitable guides such as a and c respectively
the weight or downward pressure of the said parts a A, B and O being adjustable
by the means of shot or other weights such as S (Fig. 1) or a spring f (Fig. 4)
the said parts A, B, O being contained within a casing D, having steam passages
such as E and H H', the former open to an exhaust F, and the latter formed by
a jacket such as G G¹, the said casing and jacket having flanges such as J and
bolts L, and plate or block K, for connecting the whole to the boiler, the said
plate or block having a chamber M open to the boiler, and provided with steam
passages bb leading to H H', the said chamber having therein a shaft P with
cam e adapted to be rotated by a handle or lever R for causing the said cam to
collide with an extension N on the lower end of A for shutting down and other
blowing off purposes, the whole connected combined and operating substantially
as and for the purposes described and shewn.
Dated this 2nd day of June 1808
GEO. THOS. HYDE,
1, Broad Street Buildings, Liverpool Street, London, E.C.,
Agent for the Applicant.