Improvements in Mushroom Lift Valves.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Mushroom Lift Valves.
I, COLOMBO RICCI, of No. 8, Denmark Street, Soho, in the County of London,
Mechanical Engineer, do hereby declare the nature of this invention to be as
follows:-
:-
My invention relates to improvements in that class of valves generally called
mushroom valves; which are sometimes used in steam engines, but are more
especially employed in gas and oil motors.
The shape given to these valves and to their corresponding seatings, is that of a
cone, with sides varying from 45° to 60° of inclination.
Whether these valves are opened automatically or by mechanical means, they
are always closed by a coil or other spring.
Now, when this spring works on compression, and more especially when these
valves are placed horizontally, it happens, that although the spring may be very
accurately attached, it never pulls the valve on the axis of its stem, and the conse-
quence is, that the head not falling normally on its seat, a complete closing is
never ensured, the valve works very unsatisfactorily and is a continual trouble
to the engineer.
In order to obtain a very efficient valve, and one which will ensure at any time,
in any position, and under any circumstances an accurate and complete closing,
I make the head, (or only that part of the head which falls on the seating) and the
seating itself in the shape of a sphere or of a spherical zone.
It is obvious that by this means however badly the spring may work, or however
out of its axis, the stem may be pulled, the head of the valve will always fall
accurately on its seating, and will always ensure a complete and hermetical closing.
In practice I find that these valves so constructed, work exceedingly well and
without the least trouble or attention.
Improvements in Mushroom Lift valves.
I, COLOMBO RICCI, of No. 8, Denmark Street, Soho, in the County of London,
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 refers to improvements in that class of valves generally called,
mushroom valves, which are used sometimes in steam engines but are more
especially employed in gas and oil motors.

page_text: The shape given to these valves and to their corresponding seatings, is that of
a cone, with sides varying from 45° to 60° of inclination; and whether they are
open automatically or by mechanical means, they are always closed by a coil or
other spring.
When this spring works on compression, and more especially when these valves
are placed horizontally it happens, (although the spring may be very accurately
attached) that it never pulls the valve on the axis of its stem, with the conse-
quence that the head not falling normally on its seat a complete closing is never
ensured & the valve works thus very unsatisfactorily & is a continual trouble to the
engineer.
The object of my present invention is to obtain an efficient valve, which will
ensure at any time, in any position & under any circumstance, an accurate &
complete closing. To this effect, I make the head of these valves, or only that
part of the head which bears on the seating & the seating itself in the shape of
a sphere or spherical zone.
It is obvious that by this means, however badly the spring may work, or how-
ever out of its axis the stem may be pulled, the head of the valve will always fall
accurately on its seating & ensure a complete & hermetical closing.
In the accompanying drawing I have given an illustration of a complete valve
constructed according to the principle of my said invention. A, is the valve B,
the stem C, the casing & D, the cap for the same. E, a coil spring connected at one
end to the extremity of the stem B, & the other end to any suitable fixed point in
line with the axis of the stem. The part a, of the valve A, & its corresponding
seating b, instead of being conical as usual, are made as part of a sphere as shown
by the dotted circle c.
It is obvious that by this construction, however inaccurate or loose may be the
fitting of the stem B, & also however badly may the spring E, work the valve A,
will ensure a complete closing, for in whatever position it may fall, the zone a,
will always accurately fit the seating b. The valve A, instead of being of the shape
shown in the accompanying drawing might be made as a complete ball as shown
by the dotted circle c, without departing from the principle of my said invention.
Having now particularly described & ascertained the nature of my said invention,
& in what manner the same is to be performed, I declare that what I claim is:-
A mushroom lift valve which has its head made in the shape of a sphere or
spherical zone; with a seating of a similar & corresponding shape.
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