Improved Slide Valve Gear for Steam Engines.
Year: 1890

page_text: Late of Application, 8th May, 1890
Complete Specification Left, 31st July, 1890-Accepted, 13th Sept., 1850
PROVISIONAL SPECIFICATION.
Improved Slide Valve Gear for Steam Engines.
I, SAMUEL SMITH YOUNGHUSBAND of North Road, Darlington, in the County of
Durham, Engineer, do hereby declare the nature of this invention to be as follows:-
The improved reversible valve gear of my invention has for its object to obtain a
quick admission and cut-off and a fixed amount of lead for all degrees of expansion.
The invention consists essentially in transmitting motion from the reversing link to
the slide valve through a lever arranged and operated as hereafter described.
The link is connected to the forward and backward eccentrics in the usual way and
is pivoted in a slot or otherwise so as to permit it to oscillate and constrain it to
move bodily only in the radial direction of the shaft.
The link is provided with a die or slider to which is jointed the intermediate
lever above referred to, and which lever is fulcrumed on the weigh-shaft arms of the
reversing gear by which means the die or slider can be adjusted to any position on
the reversing link in "notching up."
To this lever is coupled the slide valve rod at a point situated at a greater radius
from the fulcrum of the lever than the point of application of the power at the die
or slider.
ated this out day or may
S. S. YOUNGHUSBAND.
By A. M. & W. Clark,
53, Chancery Lane, London, Patent Agents.
COMPLETE SPECIFICATION.
Improved Slide Valve Gear for Steam Engines.
I SAMUEL SMITH YOUNGHUSBAND of North Road, Darlington, in the County of
Durham, 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 :-
The improved reversible valve gear of my invention has for its object to obtain a
quick admission and cut-off and a fixed amount of lead for all degrees of expansion.
The invention consists essentially in transmitting motion from the reversing link to
the slide valve through an intermediate lever arranged and operated as hereafter
described.
Reference is to be had to the accompanying drawings forming part of this
specification wherein
Figure 1 is an outline elevation of the valve gear slightly "notched up," and
Figure 2 is a similar view showing the link in mid-gear, the eccentric sheaves being
supposed to be in the same position as in Figure 1.
Figure 3 is a similar view of a slightly modified arrangement in full forward gear.
Figures 4 and 5 illustrate the application of the gear to single driving locomotives
with outside steain chests.
The same letters of reference indicate like parts in all the figures.
A B are the forward and backward eccentrics and a represent their centres
respectively. They are arranged in the usual way with regard to the crank pin which
is represented by point C as being on its back centre. D is the reversing link which
is connected to the forward and backward eccentrics by rods E, F, jointed at e and f
to the ends of the link in the usual way, the link being so supported as to permit it to
Oscillate and constrain it to move bodily only in the radial direction of the crank
shaft. The link may either be supported by the centre e being carried by a die

page_text: block G free to slide in a horizontal slot g as in Figures 1 and 2 or by a swing link EL
pivoted on a fixed support and jointed at to the bottom of the link D, as in Figure 3,
the motion of the link D being the same in either case. The link D is provided with
a slider or dio 1 fitted to slide on a solid link D, as in Figures 1 and 2, or in an open
link D, as in Figure 3, and carrying a pin i to which is jointed the intermediate
levor K. This lever K is fulcrumed at k on the end of the weigh shuft arms L of the
reversing gear by which means the die or slider I can be adjusted to any position
along the reversing link D for "notching up." To this lever K is coupled the slide
valve rod M at a point m situated at a greater radius from the fulcrum k of the lever
than the point of application of the motion to said lever through the eccentrics, rods,
link D, and the dio or slider I so that the travol of the slide valve N will be greater
than it would be if connected directly to the die or slider.
In Figures 4 and 5 the eccentric A is carried by a boss shrunk on to the projecting
end of the wheel axle; and the other eccentric B is carried by A.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is.
1. In a link motion, the combination, with the reversing link and the slide valve,
of an intermediate lover coupled to the link by a centre which is adjustable along
the link and connected to the slide valve at such a point with regard to such centre
as to transmit motion from the link to the valve in an increased ratio, substantially as
described.
2. In the herein described link motion in which motion is transmitted from the link
to the valve through an intermediate lever, as specified the supporting of the link
so that it is freo to oscillate but is constrained to move bodily only in the radial
direction of the crank shaft, substantially as shown and described.
1819 514 day of MLY PASSEU
Hate ima 514 day of MLY 1892D
S. S. YOUNGHUSBAND.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agonts.