An Improved Arrangement of Apparatus for Operating Corliss Valves of Steam Engines.
Year: 1891

page_text: Date of Application, 12th Feb., 1891
Complete Specification Left, 12th Nov., 1891-Accepted, 12th Dec., 1891
PROVISIONAL SPECIFICATION.
An Improved Arrangement of Apparatus for Operating Corliss
Valves of Steam Engines.
I, FRANCISCUS GYSBERTUS SCHIPPERS, of No. 5 Church Street Brighouse, in
the County of York, Mechanical Draughtsman, do hereby declare the nature of
this invention to be as follows:-
My invention has reference to a new form of trip gear for opening Corliss valves
working in connection with steam engines, the object of my improvements being to
arrange the apparatus in a more direct and simple manner, and to reduce the work
thereon by the governor to a minimum. In arranging my invention I make use of
the ordinary wrist-plate for opening the valves as hitherto, but to the end of a
connecting rod attached to the wrist plate, I hinge a pawl provided on its underside
with a steel projection made to catch with a corresponding steel projection attached
to the periphery of a pair of discs, the said discs being coupled together by a boss
and keyed upon the valve spindle. The loose end of the pawl is connected by a
short lever arm and connecting rod to the governor, which governor imparts to the
said lever arm and connecting rod a slight oscillating movement during each stroke
of the engine. The pawl and the short lever arm are connected together by a stud
provided with a cam which rides over another cam on the edge of the discs. A
spiral spring in connection with the pawl is employed to force the pawl down upon
the discs so as to keep the cam surfaces together, which cams are employed for the
purpose of lifting the pawl and disengaging the projections on the underside of the
pawl and on the topside of the disc so as to release the parts to permit a vertical
connecting rod attached to the disc and to a dash-pot below it to close the valve.
The period of the stroke when the cam on the stud comes in contact with the cam
on the disc is regulated by the governor operating the lever on the cam stud. The
combination of the pawl and the cam stud with the lever on its end for giving a
large purchase reduces the work to be done by the governor to a minimum, and as
the pawl and disc together with connecting rod and dash-pot are all in one vertical
plane the wear and tear of the parts is very much lessened and by placing the
governor between the steam valves and in front of the cylinder, the arrangement
is simple and the connection between it and the gear is direct.
Dated this 10th day of February 1891.
TASKER & CROSSLEY,
Halifax, Agents.
COMPLETE SPECIFICATION.
An Improved Arrangement of Apparatus for Operating Corliss
Valves of Steam Engines.
I, FRANCISCUS GÏSBERTUS SCHIPPERS, of No. 5 Church Street, Brighouse, in
the County of York, Mechanical Draughtsman, 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 has reference to a new form of trip gear for opening Corliss valves
working in connection with steam engines, the object of my improvements being to
arrange the apparatus in a more direct and simple manner, and to reduce the work
thereon by the governor to a minimum.
In order that my invention may be better understood, I will now proceed to
describe the same more fully, illustrating such description by reference to the

page_text: annexed sheets of drawings, wherein Fig. 1 is front elevation of my improved
arrangement of apparatus for operating the Corliss valves of steam engines, and
Fig. 2 is vertical cross section of same. The several parts shewn represent the
positions they occupy when the piston has reached the back centre ready for the
forward stroke, A representing the steam inlet valves and B the exhaust
valves. C is an ordinary wrist plate, which is made to oscillate for operating
the inlet valves A by means of the eccentric rod D, the motion of the said
wrist plate being transmitted to the steam valves by means of the connecting rod I
and pawl J hereinafter more fully described. The exhaust ports B are operated
by a second wrist plate C', which is made with a sleeve F and rides loosely upon
the boss of the first named wrist plate; such said second wrist plate C being
operated by the eccentric rod E, whilst the motion of the said wrist plate C₁
is transmitted to the exhaust valves through the medium of the crank G and
connecting rod H. Referring again to the steam valves, it will be observed that on
the end of the said pawl J is a short lever arm L, connected by rod M to a hanging
lever arm O, which also carries a short link or lever arm N (shewn in dotted lines
Fig. 1) connected by stud to the sleeve P working on the governor spindle Q, such
sleeve having an upward and downward motion imparted to it by the irregular
motion of the governors, as is well understood.
On the valve spindle A is keyed a compound disc R composed of two sides (see
enlarged details Figs. 3, 4, and 5) and held together by an intermediate boss S. A
piece of steel or other suitable material a is let into the periphery of the two sides
of the disc R and made secure by set screws or other suitable means; and
there is also let into the periphery of the said discs, a piece of leather or other
suitable material b, and projecting up between the two sides of the said disc is
a cam or cam-like projection c; these several parts being more clearly shewn in
Figs. 3, 4, and 5.
There is attached on the underside of the pawl J a steel projection d which is
employed to catch hold of the corresponding steel projection a, attached to the
periphery of the compound discs; and in order to keep the catch d of the pawl in
contact with the catch a on the periphery of the discs, a small spring is enclosed in
a box e carried on stud e¹, shewn more clearly in Fig. 6. A detail of the pawl J
with its catch d is shewn in Fig. 7, whilst Fig. 8 is a view of the pawl as seen from
the underside. The stud which connects the pawl J with the short lever Lis
provided with a cam 9, which when forced upon the cam c between the discs R,
separates the steel catches a and d, as hereinafter described; enlarged details of
the stud and cam g being shewn in Figs. 9 and 10. To the disc R there is
also attached one end of a vertical rod T in communication with the dash-pot U
operated as hereinafter described.
The action of the apparatus is as follows:--
The steam inlet valves are opened by the oscillation of the wrist plate C
through the intervention of the connecting rods I, the pawl J, and the compound
disc R. During the period of opening the valve, the angle between the pawl J
and the lever arm L is gradually lessened, causing the cam g to act upon the
projection c, thereby raising the pawl J until the contact between the catches a
and d is broken. The valve spindle being thus released is turned back by the
action of the vertical rod T, which is operated by a spring in the dash-pot U,
thereby closing the valve. The rise and fall of the sleeve P on the governor
spindle is transmitted to the lever arm L by the levers N and O and the
rod M, causing the cam g to act sooner or later on the projection c, thereby
altering the point of cutting off the steam, in accordance with the position of
the governor.
The combination of the pawl J and the cam stud f with the lever L on its
end gives a large purchase and thereby reduces the work to be done by the
governor to a minimum, and as the pawl J and disc R, together with the vertical
rod T and dash-pot U are all in one vertical plane, the wear and tear of the parts
is very much lessened; and by placing the governor between the steam valves and

page_text: in front of the cylinder, the arrangement is simple and the connection between it
and the gear is direct.
When applying my improved trip gear to existing engines, it may not be possible
or convenient to place the governors in front of the cylinder as already shewn and
described. It will therefore under such conditions be necessary to couple the
governor to the trip gear in any convenient position outside the cylinder, one
method of doing which is illustrated in Fig. 11 where Q is the governor spindle
and P the sleeve working thereon. O represents the hanging levers made with
segments W operated by rod Y by the varying motion of the governor sleeve P.
The lever arms O are connected by rods M to the trip gear in the same manner as
that already described in the previous drawings.
Having now particularly described the nature and object of my said inven-
tion, and shewn in what manner the same may be performed, I declare that what
I claim is :-
Firstly. In apparatus for operating Corliss valves, the connecting of the pawl J
direct with the wrist plate in manner described and shewn in the drawings.
Secondly. In apparatus for operating Corliss valves, the combination of the
pawl J and the cam stud f with the lever L, in manner and for purposes
described.
Thirdly. In apparatus for operating Corliss valves, the arrangement of parts
comprising the pawl J, compound discs R, connecting rod T, and dash-pot U,
arranged on the same vertical plane, substantially as herein shewn and described.
Fourthly. The general arrangement and combination of parts substantially as
herein shewn and described, for operating Corliss valves of steam engines.
Dated this 11th day of November 1891.
TASKER & CROSSLEY,
Halifax, Agents.