Valves for Steam Engines.
Year: 1885

page_text: Valves for Steam Engines.
We JONATHAN HOLDEN JAMES BURNLEY, and JOSEPH FAWELL Commission
Wool Combers, and JAMES TIDSWELL, Engineer all of Cumberland Works,
Bradford, in the County of York, do hereby declare the nature of our invention
for A NEW OR IMPROVED GEAR FOR OPERATING THE CORLISS TYPE OF VALVES
FOR STEAM ENGINES, to be as follows:-
This invention consists of a new or improved gear for operating Corliss valves of
steam engines, by means of which the complicated tripping motion, and its
accessories ordinarely employed is dispensed with and the valves are opened. and
closed with more certainty and precision than heretofore.
Our invention is applicable to all classes of Corliss cylinders but it is hereinafter
described as applied to a horizontal engine. In which case we employ a horizontal
shaft (hereinafter called the tappet shaft) placed parallel to the axis of the
cylinder, which, shaft is driven by mitre gearing from, and at the same speed as
the crank shaft of the engine. This tappet shaft is fitted with four tappets, two
of which operate the admission valves of the cylinder, and the remaining two
operate the exhaust valves. Immediately over the admission tappets suitable
guides are fixed, preferably to the side of the cylinder, in which guides, slide
blocks are fitted mounted with friction rollers resting upon the admission tappets,
and rods attached to each slide block connect such blocks with levers fitted on the
ends of the admission valves spindles. Similar guides and slide blocks are fitted
under the exhaust tappets such blocks being connected by rods to levers on the
ends of the exhaust valves spindles; thus at each revolution of the tappet shaft a
reciprocating motion is imparted to the four slide blocks working in the guides,
and to the connecting rods attached thereto, which motion is communicated to the
levers on the ends of the valve spindles, and the valves thereby opened. Ordinary
dash pots may be employed for closing the valves and keeping the friction rollers
on the slide blocks against the tappets, or we may use suitable weighted levers,
springs or other means for that purpose,

page_text: -
The admission and exhaust tappets are of such a form, and so arranged on the
tappet shaft that the admission and exhaust valves are opened & closed in the
most approved manner for economically using, steam. And such tappets are
preferably made in two parts, one part consisting of a boss fixed on the tappet
shaft and formed with an arm, or web, on which the second or projecting part of
the tappet is fixed; thus when a new tappet is required, or when, for the purpose
of admitting more or less steam to the cylinder, a tappet of different form is
desirable the second or projecting part of the tappet may be readily exchanged for
another more suitable for the purpose required.

page_text: en gear for Operating the Corliss Type or
Valves for Steam Engines.
We JONATHAN HOLDEN, JAMES BURNLEY, and JOSEPH FAWELL, Commission
Wool Combers, and JAMES TIDSWELL, Engineer, all of Cumberland Works,
Bradford, in the County of York, do hereby declare the nature of this invention for
A NEW OR IMPROVED GEAR FOR OPERATING THE CORLISS TYPE OF VALVES FOR
STEAM ENGINES and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This invention consists of a new or improved gear for operating Corliss valves
of steam engines, by means of which the complicated tripping motion and its
accessories ordinarily employed are dispensed with, and the valves are worked
with more certainty and precision than heretofore.
Reference is to be had to the accompanying drawing forming a part of this
specification in which similar letters of reference indicate corresponding parts in
all the figures.
Figure 1 is a plan of such parts of a horizontal engine fitted with Corliss valves
as are necessary to illustrate the application of our invention. Figure 2 is an end
elevation, and Figure 8 is a side elevation of the cylinder and valve gear of
the same.
Figures 4, 5, 6 and 7 are views of details hereinafter referred to.
A shaft A (hereinafter called the tappet shaft) lying parallel to the axis of the
cylinder, is mounted in bearings fitted in brackets B, and is driven at the same
speed as the crank shaft C of the engine by the mitre wheels D_connecting it to
such shaft. Two admission tappets E and two exhaust tappets F are mounted on
the tappet shaft A and act upon antifriction rollers G mounted on slide blocks H
working in vertical guides I formed at the end of brackets J secured on suitable
projections K formed on the outside of the cylinder L. Rods M (the length of
which is capable of slight adjustment in order to facilitate setting the valves)
connect the said slide blocks H to levers N secured on the admission valve
spindles O and the exhaust valve spindles P; thus at each revolution of the tappet
shaft the tappets E and F impart a reciprocating motion to the slide blocks H
which motion is communicated to the admission valve spindles O and to the
exhaust valve spindles P by the rods M and levers N, thereby opening the valves.
To close the valves, and keep the antifriction rollers G mounted on the blocks H
against the admission and exhaust tappets, springs are employed acting against
pistons enclosed in ordinary dash pots Q, the said pistons are connected by rods R
to levers S secured on the valve spindles O and P.
The tappets E and F are so relatively arranged on the tappet shaft, and they
are so formed, that the admission and exhaust valves are operated in a manner
consistent with the efficient working of the engine.
It is obvious that with slight modifications our improved valve gear is appli-
cable to vertical or other Corliss engines with one or more cylinders, and that the

page_text: admission or exhaust valves may be independently operated in the manner above
described, ordinary or separate mechanism being employed to operate either of the
pairs of valves; and also that weights may be arranged and used in lieu of the
springs and dash pots herein mentioned.
In order to facilitate changing the form of the tappets, when it is desirable to
modify the action of the valves, or when it is necessary to change such tappets, the
nose or proud portion of the tappet is separately formed and connected to the boss
of the tappet.
Figures 4 and 5 represent a side and end view of the admission tappets E.
Figure 6 is a side view of the boss of the tappets, and Figure 7 is an end view of
the exhaust tappets F.
The nose piece T is secured by the bolt or bolta U to the web V projecting from
the boss W.
Having now particularly described and ascertained the nature of our said
Invention, and in what manner the same is to be performed we declare what
we claim is:
1. In a Corliss engine, the combination and arrangement of admission and
exhaust tappets, secured on a tappet shaft parallel with the axis of the cylinder,
arranged to act upon slide blocks working in guides at right angles to such tappet
shaft, and connected to levers on the valve spindles, substantially as herein shown
and described and for the purpose specified.
2. In a Corliss engine, the combination of the above described valve gear, with
admission and exhaust tappets formed in two parts, substantially as herein shown
and described and for the purpose specified.