Improvements in or applicable to the Valves and Valve Gear of Steam Engines.
Year: 1899

page_text: Date of Application, 10th Aug., 1899
Complete Specification Left, 20th Apr., 1900-Accepted, 23rd June,
19C0
PROVISIONAL SPECIFICATION.
Improvements in or applicable to the Valves and Valve Gear of Steam
Engines.
I, WILLIAM LEES, of 28, Carrington Street, Hollinwood, near Oldham, in the
County of Lancaster, Engineer, do hereby declare the nature of this invention
to be as follows:-
My said invention relates to improvements in or applicable to the valves and
valve gear of steam engines.
According to the first part of my said invention the valves are mounted in
steam chests placed at each end of the steam cylinder in such a manner that
one wall of each steam chest forms the cylinder end in which the ports for the
passage of the steam are formed. The valves are so arranged as to travel at
right angles to the centre line of the piston rod by the oscillation of a rocking
shaft from which two arms extend to which the valves are secured. A third
arm or lever extending from the rocking shaft is connected with the eccentrics
or other means for operating and controlling the valves. In some cases I use
cylindrical valves or straight slide valves alone. In other cases I combine the
two types using cylindrical valves as cut off valves inside the straight slide valves.
According to the second part of my said invention which relates to means for
operating and controlling the valves I derive the motion for operating the
valves from the connecting rod on which is fulcrumed a slide bar working in
guides in a disc which rotates about a fixed axis when the connecting rod moves
to and fro. Secured to and rotating with the said disc is a crank pin which
operates a second slide bar working in guides in a control block. The latter
is mounted on a stud fixed to a convenient part of the engine framework in such
a way that it may be set at any desired angle and thus determine the direction
of rotation of the crank shaft of the engine. From a pin on, the said second slide
bar extends a bell crank or other lever connected up by suitable links and
levers with the valves for the purpose of operating the latter from the connect-
ing rod. In some cases I connect the control block with the governor or with
an independent handle for varying its inclination and thus varying the point
of cut off.
The parts are so disposed to each other that the cut off is operated while the
piston is travelling with greater velocity than at the ends of its stroke and thus
a very rapid cut off is obtained. The admission and exhaust are operated when
the piston is at its slowest speed near the ends of its stroke.
D
01
1800
E. T. WHITELOW, A.M. Inst. C.E.,
70, Deansgate, Manchester, Agent for the Applicant.

page_text: Improvements in or applicable to the Valves and Valve Gear of Steam
Engines.
1, WILLIAM LEES, of 28, Carrington Street, Hollinwood, near Oldham, in the
County of Lancaster, 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 and accompanying drawings to
which reference is hereinafter made:--
My said invention relates to improvements in or applicable to the valves and
valve gear of steam engines.
DESCRIPTION OF THE DRAWINGS.
Sheet I illustrates the first part of my said invention.
Fig. 1 is a transverse section, Fig. 2 is a sectional elevation of a steam engine
cylinder and valves.
Fig. 2 is a sectional elevation of an alternative construction of valve.
Sheet II illustrates the second part of my said invention.
Fig. 3 is a side elevation showing the application of the mechanism for
operating the valves to a horizontal steam engine.
Fig. 4 is a plan partly in section and Fig. 5 is a cross section of the same
mechanism.
According to the first part of my said invention as shown in Sheet I the
valves are mounted in steam chests placed at each end of the cylinder c in
such a manner that one wall of each steam chest forms the end of the cylinder
and in which ports for the passage of the steam are formed. The valves a travel
at right angles to the centre line of the piston rod and are operated in opposite
directions by the oscillation of a rocking shaft at the exhaust side of the
steam chest so that the pressure of the steam on the two valves is transmitted
to the rocking shaft. Two arms extend from the rocking shaft to the valves
te which they are hinged in such a manner as to compensate for the rectilinear
path of the valves. A third arm or lever c¹ is connected to the mechanism
for operating and controlling the valves. Although I prefer cylindrical valves
such as shown in Fig. 2 I might employ straight slide valves as shown in Fig. 2.
According to the second part of my said invention shown in Sheet II which
relates to means for operating and controlling the valves I derive the motion for
operating them from the connecting rod d. A pin el secured thereto follows
the path indicated by a series of circles shown in Fig. 3. The pin el forms the
fulcrum of a slide bar e working in a slide way in a disc f secured to a shaft
which revolves in a stationary bearing when the connecting rod moves to and
fro. The other end of the shaft carries a crank pin f¹ which when a variable
cut off is required operates a second slide bar g working in guide ways in a
control block h. The control block is secured to a stud or short shaft h¹ fixed
to a convenient part of the engine frame work in such a manner that it may be set
at any desired angle and thus determine the direction of rotation of the crank
shaft of the engine. For instance if the arm h² extending from the control
block is tilted up to the dotted line the engine will run in one direction. If
dropped to the dotted line y the engine will run the other way round.
This change of the inclination of the control block either for reversing the
direction of the engine or for varying the point of cut off may be effected by hand
and be secured at any point by means of a quadrant block and spring handle
as will be well understood. In Fig. 3 the mid position is shown from which it

page_text: has to be moved in either one direction or the other according to the direction
in which it is desired to drive the engine.
From a pin g on the second slide bar g or on the link which connects it to
the crank pin f¹ extends a bell crank or other lever k for operating the valves.
In order to vary the cut off automatically as the speed of the engine varies I
may connect the arm of the control block h with the governor.
In the case of an engine where it is not required to vary the point of cut off
the control block h may be dispensed with and the connection with the valve
spindle or lever may be made direct to the crank pin f'.
The parts are so disposed to each other and the lengths of the connecting
levers are so. arranged and the valves are so set that the cut off takes place while
the piston is travelling with greater velocity than at the ends of the stroke and
thus a very rapid cut off is obtained while the admission and exhaust are
operated when the piston is at its slowest speed near the ends of its stroke.
An important practical advantage which accrues from valve gear of this
description is that whether the engine be a right or left hand one the valve
gear is the same in either case.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed 1 declare that what
I claim is:-
1. The combination with the cylinder of a steam engine of valves working
at right angles to the centre line of the piston rod in chambers forming the ends
of the cylinder and operated by a rocking shaft in such a manner that the pres-
sure of the steam on the valves is transmitted to the rocking shaft substantially
as set forth and shown.
2. The combination with the connecting rod of a steam engine of the sliding
bare the disc f the crank pin f revolving therewith in a stationary bearing
and the control block substantially as set forth and shown for operating and
controlling the valves.
3. The combination with the connecting rod of a steam engine of the sliding
bar e the disc f and the crank pin f revolving therewith in a stationary bear-
ing for operating the valves substantially as set forth and shown.
4. In a steam engine the combination of valves mounted in chambers form-
ing the ends of the cylinder operated at right angles to the centre line of the
piston by a rocking shaft driven from the connecting rod through a slide bar
working in a disc revolving in a fixed bearing a crank pin revolving therewith
and links or levers extending therefrom either direct to the rocking shaft or
operating the same through a control block substantially as set forth and shown.
Dated this 17th day of April 1900.
E. T. WHITELOW. A.M. Inst. C.E.,
70, Deansgate, Manchester, Agent for the Applicant.