Improvements in Reciprocating Engines.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Reciprocating Engines.
I, ANTHONY GEORGE NEW, of the Voltage Woking, Surrey, Engineer, do hereby
declare the nature of this invention to be as follows;-
My invention has for its object to enable the stroke of a reciprocating engine
and particularly of a four cycle explosion engine to be varied while the engine
is running, and when applied to the latter class of engine presents the following
advantages . it enables the piston to be brought fully up to the end of the
cyner on the exhaust stroke, so enabling the exhaust gases to be completely
expened from the cylinder instead of being only partially expelled as is necessarily
the case in existing types of engines; it permits the intake stroke to be lengthened,
ani a larger amount of explosive mixture to be drawn in to the cylinder during
that stroke giving rise to a consequent and corresponding increase in the power of
the engine, and finally enables the stroke of the engine to be varied with conse-
quent variation of speed for a given power exerted by the engine.
To carry my invention into effect 1 connect the ordinary connecting or piston
rod of a reciprocating and preferably an explosion engine, to a lever arranged
approximately at right angles to the plane in which the movements of the con-
necting or piston rod take place. This lever is also pivoted to a connecting rod
which is attached at its other end to the crank in the usual manner.
The lever is so arranged relatively to the piston rod and the crank connecting
rod that an adjustable fulcrum on which it is mounted can, when moved, vary the
relative motions of these two rods or the relative positions of crank and piston.
The position of the fulcrum of the lever I adjust by hand when my object
merely to vary either the compression space or the speed, that is to say the stroke
of any engine.
13
When however I desire to obtain the other advantages described above I prefer to
effect its alternate stroke movements by means of an eccentric, which is so arranged
as to revolve at half the speed of the crank shaft of the engine, and is so geared
as to move the fulcrum thereby increasing the stroke of the piston during the
firing and exhaust strokes causing the piston to reduce its travel during the
intake and compression strokes. By a hand adjustment combined with this auto-
mat e action I may obtain both advantages.
As an alternative arrangement when I desire to vary the stroke of the engine I
may employ instead of a solid crank an arrangement of dises in preferably radial
slets in which the crank pin is moveably secured, while it may project beyond it
into spiral slots in other discs. The position of the crank pin namely its distance
from the centre of the crank shaft and the consequent stroke of the engine can
be varied by turning the radially slotted dises relatively to the spirally slotted
dises. This relative movement can be effected by hand while the engine is running
by any suitable device. The arrangement of the discs may also be single or
double so that each end of the crank pin is secured and moved in the same manner.
The dise or dises in which the crank pin is moveably secured may be replaced by
a slotted arm or arms.

page_text: In order to obtain the scavenging action in a similar way I arrange the move-
ment of the crank pin in a slot or slots in a disc or discs or in an arm or arms,
suca movement being obtained by making the relative motion of the discs to one
another that the moveable ones relatively to the shaft revolve at the speed of
the ones fixed to the shaft. In this case instead of spiral slots cam-shaped or
eccentric shaped slots are used.
I may even use an eccentric or eccentrics mounted on the shaft freely and drive
these at one halt the speed of the crank. In this case the eccentric rod moves the
crank pin inwards and outwards for alternate revolutions of the engine, the move-
ment being gradual and smooth.
That this 99nd at Mauch
1000
I, ANTHONY GEORGE NEW, of the Voltage Woking, Surrey, Engineer, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following state-
ment:-
'
My invention has for its object to enable the stroke of a reciprocating engine
and particularly of a four cycle explosion engine to be varied, while the engine
is running, and when applied to the latter class of engine presents the following
advantages viz. it enables the piston to be brought fully up to the end of the
cylinder on the exhaust stroke, so enabling the exhaust gases to be completely
expelled from the cylinder instead of being only partially expelled as is necessarily
the case in existing types of engines; it permits the intake stroke to be lengthened,
and a larger amount of explosive mixture to be drawn in to the cylinder during
that stroke giving rise to a consequent and corresponding increase in the power of
the engine, and finally enables the stroke of the engine to be varied with conse-
quent var ation of speed for a given power exerted by the engine.
In order that my invention may be the more fully understood I refer to the
accompanying sheets of drawings in which Fig. 1 represents a vertical section of
my eng me in its simpler form, while Fig. 2 represents the form which I employ
for popest amongst others of producing a complete exhausting or scavenging
(the water jacketted cylinder of the engine. The admission and exhaust
vale have not been shown as I desire only to illustrate the general arrangement
and novel features of my invention.
Pis the piston.
Ris the ordinary connecting rod which is pivotted in the slotted lever L, at p.
Ris the comperting rod, connecting the slotted lever L with the crank K of the
engine and pivotted to the slotted lever at pl.
His a block torming the fulcrum of the slotted lever L which may be raised
or lowered by turning the hand-screw S, which terminates in the square end E
and has its bearings in the bracket or frame F.
In Fig. 2 the same parts are described and referred to by the same letters. The
Fig. 2 however shows the additional parts namely, the rods R3 R2 and the eccen-
trie W, together with a short lever / pivotted at 13 and connecting the rods R³ R³.
The operation of my engine as shown in Fig. 1 is as follows:--When the block
or tulerum H remains in one position the stroke and velocity of the engine remain
constant, but by raising or lowering the block H by turning the screw S by means

page_text: of its square end E, I am enabled to vary the stroke of the engine, and consequently
its velocity this being dependent upon the effective length of the slotted lever L
which in turn depends upon the position of its fulcrum H. When I desire to
obtain the advantage of completely expelling the exhaust gases from the cylinder
during the exhaust stroke employ the arrangement shown in section in Fig. 2.
Here movements of the block or tulerumi H are effected during each cycle of the
engine by the system of rods R R which are actuated by the eccentric W shown
in dotted lines and geared to the main shatt of the engine by a 1 to 2 gear. The
operation of the eccentric and the system of levers is such as to bring the fulcrum Li
into its position in which it lengthens the stroke of the piston P bringing it right
up to the end of the cylinder at the end of the exhaust stroke. The variations in
the stroke of the engine are produced in this case as in the other by turning the
screw which raises or lowers the block H in which the rod R slides. By thus
combining the automatic action of the eccentric W and the rods R² R³ with the
hand adjustment produced by turning the screw S, I am enabled to obtain both
the above mentioned advantages.
As an alternative arrangement when I desire to vary the stroke of the engine I
may employ instead of a solid crank an arrangement of discs in preferably radial
slots in which the crank pin is moveably secured, while it may project beyond it
into spiral slots in other discs. The position of the crank pin namely its distance
from the centre of the crank shaft and the consequent stroke of the engine can
be varied by turning the radially slotted discs relatively to the spirally slotted
dises. This relative movement can be effected by hand while the engine is running
by any suitable device. The arrangement of the discs may also be single or
double so that each end of the crank pin is secured and moved in the same manner.
The disc or discs in which the crank pin is moveably secured may be replaced by
a slotted arm or arms.
In order to obtain the scavenging action in a similar way I arrange the move-
ment of the crank pin in a slot or slots in a disc or discs or in an arm or arms,
such movement being obtained by making the relative motion of the discs to one
another that the moveable ones relatively to the shaft revolve at half the speed of
the ones fixed to the shaft. In this case instead of spiral slots cam-shaped or
eccentric shaped slots are used.
I may even use an eccentric or eccentrics mounted on the shaft freely and drive
these at one half the speed of the crank. In this case the eccentric rod moves the
crank pin inwards and outwards for alternate revolutions of the engine, the move-
ment being gradual and smooth.
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
18:―
1. The method of varying the stroke of a reciprocating engine by connecting
the piston to the crank through a lever or equivalent appliance the effective length
of which can be varied substantially in the manner and for the purposes shown
and described.
2. The method of varying the stroke of a reciprocating engine by means of con-
necting the piston to the crank through a lever or equivalent appliance the effective
length of which can be varied in combination with a system of levers rods and an
eccentric or equivalent appliance so as to produce variations in the stroke of the
engine automatically during its cycle while running substantially as shown and
described.
Dated this 22nd day December 1898
R. N. LUCAS,
Agent for Applicant.