Improvements in or relating to Valve Gear.
Year: 1893

page_text: Date of Application, 23rd Feb., 1893
Complete Specification Left, 18th Oct., 1893-Accepted, 18th Nov., 1893
PROVISIONAL SPECIFICATION.
Improvements in or relating to Valve Gear.
A communication from GEBRÜDER MEER, of M. Gladbach, in the Empire of
Germany.
I, ALFRED JULIUS BOULT of 323 High Holborn, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be as
follows:-
The improvement herein described is based upon the employment in connection
with valve-gearing, of an eccentric lever adapted freely to swing on the terminal
point of the rod or link connection and to be compulsorily deflected from its course
to an extent corresponding to the quantity of steam to be admitted for the time
being, by coming into contact with a stationary bearing point.
The adjustment of this bearing point, which is effected by the governor and may
vary to any desirable extent, from zero up to practically indefinite pressures,
requires no special operation. Besides, the reaction which it sustains is reduced
practically to nothing; so that upon the whole the adjustability thus obtained may
be said to be more satisfactory than that of which any of the arrangements hitherto
known have allowed.
The improved valve-gear may be constructed in various ways, a preferred form
of the apparatus being that hereinafter described.
The inlet-valve and the outlet-valve are each independently of one another
operated by an eccentric, the admission eccentric being keyed upon its shaft in
such a position that it begins its stroke at the moment when the crank is at the
dead point. The transmission of the motion of this admission eccentric for the
purpose of regulating the inlet takes place by means of a yoke-shaped lever.
The terminal point of this lever or yoke engages with the connecting rod or link
of the admission device operated by a lever while near the centre of the said yoke
there is provided a recess or pocket in which is located a roller of preferably
hardened steel.
In the seat of the governor is supported along with the valve-spindle, a second
spindle of less diameter, adapted to be operated by the governor through the
medium of a lever.
Upon the ends of this spindle are mounted the adjusting or controlling discs each
of which is provided on the front side with a crank-pin upon which is adapted to
turn a roller of preferably hardened steel. Each disc is enclosed in a casing which,
while enabling it to turn, is capable as much as possible of deadening the shocks
occurring in the operation of the governor. At its upper edge it is provided with a
scale indicating the degree or extent of "filling." The governor is adapted to
move the crank pin together with the roller from the horizontal position to a nearly
vertical position, according to the degree of "filling" varying between 0 and 65 or
even 70%. If the filling indicated be zero with the crank at the dead point, the
centres of the inlet-eccentric, valve-spindles and rollers will all be situated in a
straight line, while the terminal point of the yoke projects beyond this line to an
extent corresponding to the amplitude of the opening produced. This first opening
is effected under the influence of a lever interposed between the admission valve
and the rod.
Now the arrangement of the rollers being such that they-in the position of the
connecting rods just described-extend past each other on straight tangential
lines, no endwise displacement or stroke of the terminal point of the yoke takes
place. It only swings about the upper pivot of the connecting rod or link while
the admission device remains closed.

page_text: But whatever other position the herein second-mentioned or crank-pin roller may
assume between the limits of filling mentioned above, the other roller must always
run up against the said roller, describe an arc of a circle around it, and in so doing
open and close the inlet. Thus it will be understood that the time occupied by the
one roller in rolling along the other roller will also be the time during which the
inlet remains open, and also that both the opening and closing thereof take place as
it were compulsorily. The above mentioned preliminary opening (provided the
minimum limit of stroke in the immediate vicinity of zero has been passed) will
under all circumstances remain equal, because the centre of one roller with the
crank at the dead point is always in a line with the centre of rotation of the
adjusting or controlling disc.
The closing of the valves takes place very rapidly as a consequence of one roller
running off the other and under the action of the tilting lever.
Dated this 23rd day of February 1893.
ALFRED J. BOULT,
Chartered Patent Agent.
COMPLETE SPECIFICATION.
Improvements in or relating to Valve Gear.
A communication from GEBRÜDER MEER, of M. Gladbach, in the Empire of
Germany.
I, ALFRED JULIUS BOULT of 323 High Holborn, in the County of Middlesex,
Chartered Patent Agent, 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 improvement herein described is based upon the employment in connection
with valve-gearing of an eccentric lever adapted freely to swing on the terminal
point of the rod or link connection and to be compulsorily deflected from its course
to an extent corresponding to the quantity of steam to be admitted for the time
being by coming into contact with a stationary bearing point.
The adjustment of this bearing point which is effected by the governor and may
vary to any desirable extent from zero up to practically indefinite pressures, requires
no special operation. Besides the re-action which it sustains is reduced practically
to nothing; so that upon the whole the adjustability thus obtained may be said to
be more satisfactory than that of which any of the arrangements hitherto known
have allowed.
The improved valve-gear may be constructed in various ways, a preferred form
of the apparatus being illustrated by the accompanying drawings in which
Figure 1 represents the back of a cylinder provided with the improved valve-
gear.
Figure 2 is a longitudinal section of a disc or cam and rollers, and
Figure 3 illustrates the principle of motion of the eccentric lever.
The inlet-valve and the outlet-valve are each independently of one another
operated by an eccentric, the admission eccentric being keyed upon its shaft in such
a position that it begins its stroke at the moment when the crank is at the dead
point. The transmission of the motion of this admission eccentric for the purpose
of regulating the inlet takes place by means of a yoke-shaped lever B.
The terminal point of this lever or yoke B engages with the connecting rod or
link Z of the admission device operated by a lever H while near the centre of the
said yoke there is provided a recess, or pocket (Figure 2) in which is located a
roller c of preferably hardened steel.
In the seat of the governor is supported along with the valve-spindle, a second
spindle c¹ of less diameter adapted to be operated by the governor through the
medium of a lever C (Figures 1 and 2).

page_text: Upon the ends of this spindle are mounted the adjusting or controlling discs D
each of which is provided on the front side with a crank-pin upon which is adapted
to turn a roller d of preferably hardened steel. Each disc is enclosed in a casing D¹
which while enabling it to turn is capable as much as possible of deadening the
shocks occurring in the operation of the governor. At its upper edge it is provided
with a scale indicating the degree or extent of " filling." The governor is adapted
to move the crank-pin together with the roller d from the horizontal position to a
nearly vertical position, according to the degree of "filling" varying between 0.
and 65 or even 70 per cent. If the filling indicated be zero with the crank at the
dead point, the centres of the inlet-eccentric, valve-spindles roller c and roller d will
all be situated in a straight line (a horizontal line in this instance) while the terminal
point of 6 projects beyond this line to an extent corresponding to the amplitude of
the opening produced (Figure 3). This first opening is effected on the way from a
to b under the influence of the lever H interposed between the admission-valve and
the rod.
Now the arrangement of the rollers c and d being such that they-in the position
of the connecting rods just described-extend past each other on straight tangential
lines no endwise displacement or stroke of the terminal point of the yoke takes
place. It only swings about the upper pivot of the connecting rod or link Z while
the admission device remains closed.
C
But whatever other position the roller d may assume between the limits of filling
mentioned above, the roller c must always run up against the said roller d describe
an arc of a circle around it and in so doing, open and close the inlet. Thus it will
be understood that the time occupied by the roller e in rolling along the roller d
will also be the time during which the inlet remains open; and also that both the
opening and closing thereof take place as it were compulsorily. The above
mentioned preliminary opening (provided the minimum limit of stroke in the
immediate vicinity of zero has been passed) will under all circumstances remain
equal, because the centre of the roller c with the crank at the dead point is always
in a line with the centre of rotation of the adjusting or controlling disc D.
The closing of the valves takes place very rapidly as a consequence of the roller c
running off d and under the action of the tilting lever H.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondents, and in what manner
the same is to be performed, I declare that what I claim is ;-
In valve gearing the arrangement of two rollers (c and d) running against and
capable of rotating one upon the other one (c) of said rollers being located in a
recess or pocket of the lever or yoke (B) the terminal point (6) of which engages
with the connecting rod of the admission valve operated by the lever (H) while the
other roller (d) is controlled by the governor in such a manner that it operates in
an arc of a circle having a radius equal to the sum of the radii of c and d and
determines the duration of "filling" substantially as described and illustrated in the
accompanying drawings.
Dated this 14th day of October 1893.
W. P. THOMPSON & BOULT,
Agents for the Applicant.