Improvements in Gas and Petroleum Engines.
Year: 1891

page_text: Date of Application, 18th Mar., 1891-Accepted, 18th Apr., 1891
COMPLETE SPECIFICATION.
Improvements in Gas and Petroleum Engines.
I, OTTOCAR LINDEMANN, Engineer, of 86, Queen Street, Cheapside, London,
E.C., 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 has for its object the production of a varying power by means of
a mechanical arrangement worked by a governor which closes partly or entirely
the inlet of the explosive charge-either valve or slide-before the end of the suction
stroke of the piston proportionately to the resistance, which the aforesaid gas or
petroleum engine has to overcome.
If the inlet valve or slide be closed or throttled at a certain point of the suction
stroke of the piston an expansion of the gases in the cylinder takes place up to the end
of the stroke, provided that the outlet for the exhaust be kept closed, and at the same
rate the quantity of combustible mixture in the charge is reduced. On the return
stroke of the piston the gases are compressed, and the maximum compression
attained at the dead point, when the charge is ignited, will be more or less high
according to the height of the previous expansion.
The characteristic feature of this invention is that the quantity of combustible
mixture in each charge together with the compression at the dead point of the
crank is variable. The compression is the least with the smallest charge and the
greatest with the full charge, while the expansion is the greatest with the minimum
charge and the least with the full charge.
In order to obtain an equally exact ignition in case of both poor and rich charges.
it is desirable to make the action of the igniter dependent upon the governor so
that the ignition takes place earlier with poor charges than with rich charges.
Fig. 1. represents a construction in which a link a is moved by means of two
The rod e
eccentrics b and c, and the bellcrank d directly from the crank shaft.
which is connected to the link block y lifts by its motion to the right the bellcrankf
so that the automatic inlet-valve k can open but must always follow the lever fin
its upward motion. The link block y is adjusted by means of the governor h, and
the rod i according to the power developed by the engine. At the inner dead point
of the crank the position of the link a is such that any movement on the part of the
link block g has no appreciable effect upon the lever f, but has such effect on the
lever 1, which is also connected to the link block g by rod m, and which, when link
block g is at its lowest point (with minimum charge) opens the ignition valve n
owing to the slanting position of rod m somewhat sooner, than when the block g
is at its highest position, and thus causes an earlier ignition of the weaker
mixture.
The movement of the link a is so adjusted that, when the block g is at its highest
point, the lever allows the inlet valve k to open during the whole of the suction
stroke, but when the block y is at its lowest point, shuts the valve k shortly after
the commencement of the suction stroke so that the mixture sucked in will be
only sufficiently powerful to meet the requirements of the engine when running
light.
The lever will be lifted at the expansion stroke of the piston, but that does not
necessitate the raising of valve k. The igniter will be affected at the end of the
exhaust stroke. Both these movements however exercise no effect on the action of
the engine.
Figs. 2 and 3 represent an arrangement in which a governing shaft to which
performs half the number of revolutions of the crank shaft works the valves or

page_text: slides by means of the diagonal liigs p and q made movable on the shaft to, and of
which the position is controlled by the governor o.
The lug which governs the inlet valve by means of the lever r is so arranged
that through its horizontal movement by the governor the inlet valve always opens
at the dead point of the crank at the beginning of the suction stroke, but that the
closing of the valve varies in point of time according to the position of the
governor.
1
The lug which actuates the igniter by means of lever s allows the ignition to
take place earlier with a poor charge, but with a full charge immediately before
the dead point of the crank at the commencement of the expansion stroke.
The exhaust valve may be governed in both cases according to any known
method.
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. The regulation of the power in gas and petroleum engines by closing or
throttling the inlet for the explosive mixture according to the load on the engine
sooner or later before the end of the suction stroke of the piston by means of a regu-
lating arrangement worked from the governor, the exhaust outlet being kept in the
meanwhile closed so that a corresponding variation of the quantity of combustible
mixture in the charge takes place, connected with a variable expansion and
following compression of the charge before its ignition, substantially as described."
"2. The connection of the governor with the mechanism which controls the
igniter in such a way, that with a small charge in the cylinder-i.e. with a weak
charge the igniter will be actuated earlier than with a full charge-i.e. with a
strong mixture,-substantially as specified."
Dated this Eighteenth day of March 1891.
OTTOCAR LINDEMANN.