IMPROVEMENTS IN VALVE GEAR FOR THE DISTRIBUTING VALVES OF STEAM AND OTHER MOTORS
Year: 1884

page_text: I CONSTANTYN PIETER HOLST of N° 264 Jan Steen Straat, Amsterdam, in the
Kingdom of the Netherlands, Engineer and Teacher at the Government School at
Amsterdam do hereby declare the nature of my Invention for "IMPROVEMENTS
IN VALVE GEAR FOR THE DISTRIBUTING VALVES OF STEAM AND OTHER MOTORS"
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
According to this Invention there is given to the eccentric rod or rods (or its
or their equivalents) which operates or operate the distributing valve of a steam
or other motor a motion similar to that of the piston rods in oscillating cylinder
engines instead of the ordinary swinging motion similar to that of a connecting rod.
To this end instead of guiding some fixed point on the eccentric rod through any
desired line the object sought by this Iuvention is attained by guiding a fixed line
drawn through the centre of the eccentric sheave (or pin) on the eccentric rod (or
its equivalent) either exactly or approximately, through a point fixed relatively to
the framing of the engine.
According to one method of carrying out the Invention a prism or sliding block
is rigidly attached to the eccentric rod (or its equivalent) and is arranged to work
through or between guides oscillating on a pin carried by the framing of the
engine. If, however, absolute exactness be not required in the movement of the
eccentric rod, then it is more convenient to guide it by attaching a pin to the
eccentric rod at a point chosen at some convenient distance from the fixed line
above mentioned and connecting this pin by a link to a pin carried by the framing
of the engine and constituting a fixed fulcrum.
Motion for the valve gearing and reversing mechanism is taken in either case by
any convenient arrangement from a second point on the eccentric rod (or its
equivalent) und situated in the fixed line mentioned above.
Referring to the accompanying Sheet of Drawings;
Fig. 1 illustrates the Invention when the line is guided exactly through a fixed
point.
A is the eccentric sheave keyed on to the shaft B. The eccentric strap C carries
a prism or sliding block D rigidly attached to it and guided by an oscillating guide

page_text: block E. This block is carried by a pin F supported by a plummer block G
attached to the framing H of the engine.
Fig. II illustrates the Invention when the line is guided approximately through
a fixed point.
A is again the eccentric keyed on to the shaft B. The eccentric strap O carries
a horn with a pin D connected by a link (or links) E to the fixed fulcrum F,
supported by the plummer block G attached to the framing H of the engine.
In both cases motion for the valves is derived from the pin K in the eccentric
strap C actuating any convenient system of moving parts.
It will be evident that it is immaterial for the purposes of this Invention
whether the eccentric be a sheave on the circumference of a shaft or a pin at
its end.
It is obvious that the position of the fixed point or fulcrum F in both arrange-
ments may be above the shaft, or below it, or in any other direction relatively to
the 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. Arranging the sheave of an eccentric or its equivalent, when employed to
actuate the valve gear of a steam or other motor, in such a way that a line drawn
through the centre of the sheave and a given point in the eccentric rod, or clip, or
its equivalent shall always pass exactly or approximately through a given fixed
point substantially as described.
2. The use for actuating the distributing valve of a steam or other motor, of a
crank or eccentric sheave in combination with a rod or clip or its equivalent, having
a block, such as D, guided in a guide oscillating about a fixed point, substantially
as described with reference to Fig. 1 of the Drawings.
3. The use for actuating the distributing valve of a steam or other motor, of a
crank or eccentric sheave in combination with a rod, clip, or its equivalent
connected at one point by a link to a fixed fulcrum substantially as described with
reference to Fig. 2 of the Drawings.
D
1
J
T 1