IMPROVEMENTS IN SLIDE VALVES
Year: 1884

page_text: I, EDWARD CHARLES PECK of Number Eight Clarendon Villas, Old Charlton,
in the County of Kent England; Engineer do hereby declare the nature of iny
Invention for IMPROVEMENTS IN SLIDE VALVES and in what manner the samo
is, to be performed, to be particularly described and ascertained in and by the
following statement :-
In order to give a fuller understanding of my improvements reference is inade
to the accompanying Drawings and to the Figures and letters marked thereon;
Fig. 1 being a vertical section of a steam cylinder and slide valve, Fig. 2 is a cross
section of the same and Fig. 3 is a development of the face of the slide valve.
I combine two slide valves in a cylindrical or partly cylindrical form in one
casting as shewn in Figs. 1, 2, and 3; one of these valves is of the ordinary D form
as shewn in dotted lines in Fig. 1 at G and the other is of the Worthington type
as shewn in full lines in Fig. 1. The recesses of these two valves are separated
circumferentially by a plain part of the casting H Fig. 2 and 3 equal to or a littlo
wider than the width of the ports leading to the working cylinder as shewn in
Figs. 2 and 3; in such a manner that if the valve be turned by means of the lever A
Fig. 1 or other suitable means so that the recess B Figs. 2 and 3 be presented to
the ports the engine will run in one direction; and if the valve be turned so that
the recesses C and D Figs. 2 and 3 be presented to the ports, the engine will run
in an opposite direction; but if the valve be turned so that the plain part H
Figs. 2 and 3 be presented to the ports the engine will stop and remain stationary.
Any intermediate position between those above named will occasion a corre-
sponding speed of the engine.
I may use a modification of this combined valve in which the motion in the
direction of its axis is used for starting, reversing, regulating, and stopping; and
the tangential or transverse motion is used for distributing the steam to the
working cylinder.
Instead of combining these valves in a cylindrical form I may keep them flat
and start, reverse, regulate and stop by moving the valve in a direction transverse
to the direction of its distributing motion.
A combined valve of the above or other suitable form may be used for one of
the cylinder ports and another on the same valve spindle for the other. An
arrangement of differential gear suitable for the application of this valve to steam

page_text: steering apparatus is shewn in Figs. 4, 5, & 6 in which worm wheels are substituted
for the lever A Fig. 1; these worm wheels gear into a worm which, being turned
by the hand wheel alters the positions of the valves and is afterwards made to
work as a rack to return the valves to their former positions, by being acted on
by the lever J in communication with a screw on the engine shaft.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed; I declare that what
I claim is
1 The combination in one casting of two slide valves, each of which though
moved directly by the same fixed eccentric would give opposite effects on the
piston of the working cylinder when placed in connection with the ports thereof;
one arrangeinent of which is described in the foregoing Specification and represented
in Figs. 1, 2, and 3; in the accompanying Drawings.
2nd The moving of the combined valve described in the preceding claim for
starting, reversing, regulating, and stopping the piston of the working cylinder,
be means of the lever A Fig. 1 or its mechanical equivalent, in a direction
transverse to the direction of motion given to it by the engine.
3rd The arrangement and proportioning of the ports leading to the working
cylinder in such a manner that any two combined valves moved as before described
will have opposite effects on the piston of the working cylinder for the purposes
described in the foregoing Specification.
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