Improvements in and relating to Valve-gear for Steam Engines.
Year: 1891

page_text: Date of Application, 23rd June, 1891-Accepted, 25th July, 1891
COMPLETE SPECIFICATION.
Improvements in and relating to Valve-gear for Steam Engines.
I, FRANK HARVEY BALL, a citizen of the United States of America, residing
at Elizabeth, in the County of Union, and State of New Jersey, one of the
United States of America, Manufacturer of Engines, 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 :-
This invention relates to that class of steam-engine valve gears in which the
action of the steam-valve is varied by shifting the position of the eccentric or
crank-pin which moves it, and consists in certain improvements in the construction
of the same as will be hereinafter fully set forth and pointed out in claims.
The invention is illustrated in the accompanying drawings as follows:-
Figure 1 is a side elevation view of the fly-wheel of a steam engine with my
improved valve gear in place therein, the main-springs of the same being omitted
as the improvements hereinafter to be described in no way relate thereto, and
any of the many well known forms of springs may be used.
Figure 2 is a horizontal section taken on the line - in Figure 1, the balls and
springs being omitted.
Figure 3 is a side elevation view of the eccentric-disc and yoke with the side-
plate E, removed.
Figure 4 is a horizontal section view of the parts shown in Figure 3, below the
yy and having the side-plate E, shown in place.
line
Figure 5 is a view like Figure 1, showing modifications in the construction.
Figure 6 is a section view taken on the line - in Figure 5.
Like letters of reference indicate like parts in all the figures.
The construction and operation is as follows:
The fly-balls and main springs may be any desired construction. The position
of these springs, which are not shown, being indicated by the dotted lines - in
Figure 5.
My invention relates wholly to the construction of the valve-gear and not to the
appliances by which it is moved.
I show balls B, hung on the fly wheel A, and connected with the valve-gear by
links C, and I also show an auxiliary spring J, and dash-pot K, which are used in
my engines, but these parts do not constitute any part of my present invention.
The valve-gear (that is to say, the parts by which the valve is moved and its
movements varied) consists of an eccentric-disc G, which is secured to the end of
the hub of the fly-wheel by bolts which pass through the counter-sunk holes and
tap into the hub, a yoke D, which embraces the eccentric disc G; a face-plate E,
which is bolted to the side of the yoke D, and a crank-pin F, (or its equivalent, to
wit, the eccentric or a cam F¹, seen in Figures 5 and 6) on the side of the face
plate E.
ولا
The eccentric-disc G, is shown as bolted to the end of the hub of the fly-wheel,
but it may be cast solid with it or it may be keyed to the shaft and be distinct
from the fly-wheel, but however it may be, it should move integrally with the shaft
and fly-wheel or other frame which may support the weights and springs of the
governor.
The yoke D together with the face-plate E, embraces the eccentric-disc G, and
is movable relatively on said disc, and it is connected with the governor weights
by the links C, C, which extend from the pins C, C¹, to said weights.
The yoke and plate (D and E) are moved rotatively upon the disc G, only when
the weights move in or out, but they have a constant rotating motion with the
shaft H, and disc G.

page_text: A pin G¹, on disc G, and lugs D1, D2, on the yoke D, serve to limit the movement
of the yoke upon the disc. In Figure 1 the pin and the lugs just referred to are
in dotted lines and the position of parts is that which they occupy when the engine
is at rest. The pin G is shown in contact with the lug D².
The other extreme position would bring the lug D', into contact with the
pin G
In Figure 1, marks the center of motion of the shaft and e, the center of
motion of the yoke D, and plate E, as it is moved rotatively upon the disc G, by
the action of the weights. The dotted line f, represents the path or orbit of the
center of the crank pin F, as the shaft revolves and the arc-line f', f¹, represents
the path of the center of the crank-pin as it shifts from one extreme position to
another by the action of the weights moving the yoke D, and plate E, upon the
disc G.
The yoke D, plate E, and pin F, taken as a whole, correspond in function with
the eccentric of an ordinarily constructed shifting eccentric valve-gear, but it
differs quite materially from former constructions in its manner of application and
operation. It will be observed that it has its three centers, to wit, the center of
the shaft, the center of the crank-pin (or its equivalent, the eccentric F¹, if
used) and its geometrical center, all within its periphery and that when it moves
to shift the position of the crank-pin, it moves around its geometrical center.
The beneficial results of this construction over former constructions are, first,
that lost motion can be taken up when it occurs by reason of wear without
changing the relative position of the three centers above named: second, that wear
can be more easily taken up; and third; greater compactness and cheapness of
construction.
In the construction shown I have provided for the taking up wear as follows:-
The yoke D, has bolts d by which it can be clamped closely upon the disc G. To
enable this movement the bolts g', which fasten the plate E, to the yoke will pass
through enlarged or elongated holes in the plate E, so that when they are loosened
the two parts of the clamp can be moved. If side wear occurs the plate E, can
be removed and the side of the yoke be scraped down.
In the alternative construction shown in Figures 5 and 6 the device is so modified
that the valve-gear may be placed on the inside of the fly-wheel A, instead of on
the outside, as in the other figures. To effect this change it is necessary to provide
an elongated shaft-opening H³, in the face plate E and to substitute for the crank-
pin F, an eccentric F, which is fixed on the side of the plate E, and surrounds the
said shaft-opening H².
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :
1. In an automatic cut-off valve gear for steam engines, the combination sub-
stantially as set forth, of a plate or disc bearing the crank-pin or other means for
imparting reciprocating action to the valve which is supported so as to move
rotatively with the main shaft, is pivoted so as to turn on its own center which is
eccentric to the shaft, and has within its periphery the center line of the shaft the
center of said crank-pin, or its equivalent, and its own pivoted center, and fly-balls
so connected with said plate or disc by links as to move the same pivotally as
they move radially.
2. In an automatic cut-off valve-gear for steam-engines, the combination, sub-
stantially as set forth, of the disc G, secured eccentrically on the shaft H, the
yoke D and plate E, concentrically journaled on said disc G, the crank-pin F, or
equivalent means for reciprocating the valve, secured on said plate eccentrically
thereto and to the shaft H, and fly-balls B, connected with said yoke and plate by
links C.
3. In an automatic cut-off valve-gear for steam engines, the combination, sub-
stantially as set forth, of the disc G, secured eccentrically on the shaft H, the

page_text: adjustable yoke D, and plate E, journaled on said disc, stop lugs D', D³, on said
yoke and a stop-pin G', on said disc, a crank pin F, or its equivalent, on said plate
in a position eccentric to said plate and to the shaft H, and fly-balls connected
with said plate or yoke by links C.
4. In an automatic cut-off valve-gear for steam engines, the combination, sub-
stantially as set forth, of the disc G, secured eccentrically on the shaft H, the
yoke D, and face plate E, concentrically journaled on said disc, the face plate
having a shaft opening H², sufficiently larger than the shaft to allow of the
rotative movement of the said plate concentrically upon the eccentrically sup-
ported disc, the eccentric F¹, attached to said plate E, and surrounding said
shaft-opening H2, and the fly-balls or weights B, connected with said yoke D, by
links C.
Dated this 22nd dov of T 1901
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.