Improvements in or connected with Slide Valves for Steam Engines or other Motors.
Year: 1891

page_text: Date of Application, 8th Sept., 1891
Complete Specification Left, 4th June, 1892--Accepted, 16th July, 1892
PROVISIONAL SPECIFICATION.
Improvements in or connected with Slide Valves for Steam Engines
or other Motors.
I, GEORGE WATSON, of Springfield Place, Leeds, in the County of York,
Engineer, do hereby declare the nature of this invention to be as follows:-
The object of this invention is to give such a movement or motion to the slide
valves of steam engines or other motors over their faces. as will prevent them
wearing into grooves.
It consists essentially in giving to the valve a compound movement or a movement
in two directions which will prevent it moving in a straight line across its seat by
means of a radius link eccentric or crank tappet cam spring or equivalent
device.
In carrying out the invention the slide valve is mounted in a strap or equivalent
in which it is free to slide laterally and with which it receives its longitudinal
movement across the ports actuated by any suitable mechanism while the strap
retains its position parallel to the ports.
To the valve I attach the means for giving it a transverse movement within the
strap which moves to and fro with it. Where a radius rod or link is used one end
of the rod or link is attached or pivoted to the slide valve and the other end is
pivoted on a joint secured to the valve chest about midway of the travel of the
valve. Instead of a radius rod fixed at the outer end the valve may be connected
with an eccentric or crank driven by a belt or gearing from any rotating part of
the engine or motor. As the eccentric or crank rotates, the valve receives. the to
and fro movement in a direction at right angles to the direction of the ordinary
travel of the valve. The cross motion may also be imparted to the valve by
means of a raised circular or other facing against which the edge will come in
contact at each stroke to and fro. This facing I should prefer to make highest
at the centre and lower at the sides though this may be reversed and when found
to be desirable a corresponding surface or facing or a spring will also be applied at
the other side to move the valve in the reverse direction. The raised facing would
be placed behind the strap while the strap is bent forward to avoid. it. It will of
course be evident that a tappet or cam or similar device may be applied to the
valve to give the cross motion desired.
By thus giving the valve a cross motion in addition to its longitudinal movement,
at the same time keeping it parallel to the ports, the action of the two faces will be
similar to that of a face plate in grinding up true surfaces, and it will continually
tend to improve the surface upon the valve face instead of abrading it, and prevent
it wearing into grooves.
Dated this 7th day of September 1901
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.
COMPLETE SPECIFICATION.
0 Improvements in or connected with Slide Valves for Steam Engines
or other Motors.
I, GEORGE WATSON, of Springfield Place, Leeds, in the County of York,
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
5 and by the following statement:-
The object of this invention is to provide means whereby an additional or

page_text: transverse movement or motion will be given to the slide valves of steam engines
or other motors over their faces to prevent them wearing into grooves.
It consists essentially in connecting or attaching to the slide valve a strap or
bridle in which it can have a transverse movement and a radius link, radial cam,
tappet eccentric or equivalent device whereby a compound movement or movement
in two directions is imparted to the valve as it travels to and fro preventing it
moving in a straight line across its seat.
It will be fully described in reference to the accompanying drawings in which as
an example the invention is shown applied to one form of valve.
Fig. 1. side elevation showing a radius rod connected to the valve to give it the
required movement.
Fig. 2. end elevation of Fig. 1.
Fig. 3. side elevation showing the valve with a pin or stud attached thereto and
moving in a radial slot to give the required movement.
Fig. 4. end elevation of Fig. 3.
Fig. 5. side elevation showing the valve provided with a tappet or circular facing
on one edge to give the required movement.
Fig. 6. end elevation of Fig. 5.
Fig. 7. diagram representing path traversed by a number of points on the valve
face as it moves to and fro over its seat.
The slide valve A is of any suitable form or construction. I mount it in a strap
or bridle B in which it is free to slide transversely independently of its longitudinal
movement. but with which it at the same time receives its longitudinal movement
across the ports. The bridle or strap B during such movement always
retains its position parallel to the ports and also maintains the valve A in a similar
position.
The strap or bridle B is connected to the valve rod C which is actuated by an
eccentric or other device in the ordinary way.
To the valve AI attach or connect the means for giving it a transverse move-
ment within the strap B which moves to and fro with it.
Referring to Figs. 1 and 2 a radius rod or link D is shown connected with the
valve to give the required movement. One end of the rod or link D is pivoted to
the slide valve A by means of a projecting pin or stud a and the other end is
pivoted to a bracket E secured to the valve chest about midway of the travel of the
valve A.
Referring to Figs. 3 and 4 the pin or stud a attached to the valve travels to and
fro in a radial cam or slot e in the bracket E which as the valve moves to and fro
with the strap or bridle B imparts the required transverse movement.
Referring to Figs. 5 and 6 a raised facing or tappet F is provided on the under
edge of the valve and a similar fixed tappet or projection G upon which it slides.
As the two raised or projecting faces pass over one another the transverse motion
is imparted to the valve. The valve after it is raised may slide back of its own
weight or may be provided with a spring, or a reverse cam may be applied above
the valve to give the return movement. The facing I prefer to arrange as shown
higher in the centre and lower towards each side though this arrangement may be
reversed.
Instead of a fixed device as shown to give the transverse movement to the valve
it may be connected with an eccentric or crank driven by a belt or gearing from
any rotating part of the engine or motor. As the eccentric or crank rotates the
valve receives the to and fro movement in a direction at right angles to the
direction of the ordinary travel of the valve.
Referring to Fig. 7 the diagram represents the paths traversed by a number of
points on the valve showing how they cut across one another the tendency of every
point in the valve face being to rub out or smooth the tracks of the adjacent
points.
By thus giving the valve a cross motion in addition to its longitudinal movement
at the same time keeping it parallel to the ports the action of the two faces will be

page_text: similar to that of a face plate in grinding up true surfaces and it will continually
tend to improve the surface upon the valve face instead of abrading it and prevent
it wearing into grooves (see Fig. 7).
"
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
1. A slide valve for steam engines or other motors provided with a strap or
bridle moving with it in which it is free to move transversely and a radius rod, link
cam or eccentric to impart a transverse or compound movement as the valve
travels to and fro across the ports substantially as and for the purposes
described.
2. The combination with the slide valve of the several parts constructed and
arranged substantially as described and shown in Figs. 1 to 6 respectively of the
drawings.
- +
1000
WM. P. THOMPSON & Co.,
Manchester, Liverpool, and London, Patent Agents.