the Ignition and Expansion of a Combustible Mixture.
Year: 1886

page_text: Date of Application, 24th Sept., 1886.
Complete Left, 24th June, 1887.
Complete Accepted, 26th July, 1887.
the Ignition and Expansion of a Combustible Mixture.
We, BENJAMIN BUTTERWORTH, 16 Casson Gate Rochdale, Lancashire, Engineer,
and JOSEPH BUTTERWORTH, 16 Casson Gate, Rochdale Lancashire, Engineer, do
hereby declare the nature of this invention to be as follows :-
This invention is applicable to those engines in which the power is obtained by the
ignition and expansion of a combustible mixture, its object being to quicken the speed
of the piston during that portion of the cycle of operations in which the combustible
mixture is ignited and expanded thus lessening the time during which the hot gases
are in contact with the cylinder and as a consequence lessening the amount of heat
which passes through its walls and is lost, this first part of the invention is applicable
to both compression and noncompression engines, but for compression engines the
same mechanism also retards the motion of the piston during that portion of
the cycle of operations in which the combustible mixture is compressed thus enabling
the engine to be turned with ease when starting and doing away with the need of
self starting mechanism; in the following description where the outward stroke of the
piston is mentioned, it is intended to mean that stroke of the piston in which
the combustible mixture is ignited and expanded and where the inward stroke of the
piston is mentioned it is intended to indicate that stroke of the piston in which the
combustible mixture is compressed. The invention is carried into effect by changing
the reciprocating motion of the piston into the circular motion of the crank shaft by
means of a combination of slit or other lever or link and crank of such proportions
that the piston performs its outward stroke in much less time than the inward stroke in
a similar manner to the quick return notion as applied to small planing and shaping
machines. The crank pin of the engine works in a slot or groove in a lever which
oscillates about a fixed centre, this fixed centre is placed on one side of the crank
shaft in such a position that the crank pin is nearest to it during the time the piston
is making its outward stroke in which the gases are ignited and expanded and
considerably further from it during the time the piston is making its inward stroke in
which the gases are compressed. The piston rod may be jointed to any suitable part
[Pain Q37

page_text: of the lever but it is preferred to place the centre of the cylinder in line with the centre
of the crank shaft as in an ordinary engine and to connect the piston rod to such
part of the lever as will enable it to coincide as nearly as possible with the axis of the
cylinder in working. The lever may however be prolonged beyond the fixed centre
and the piston rod be jointed to any suitable part of the prolongation, in this case the
crank shaft would be on one side of the fixed centre and the cylinder on the other
somewhat similar to a beam engine, the lever may be modified by making it a plain
bar of uniform section and connecting it to the crank pin by means of a ferrule made
so as to slide along the lever, the action being exactly similar to that of the slotted
lever. The mechanism may also be modified by jointing the crank pin directly to the
lever, the lever in that case sliding through a ferrule at the fixed centre or the lever
might be slotted and work to and fro over a slide block the centre of which coincides
with the fixed centre, the piston rod in this case may be connected to any suitable part
of the lever as in the first form of the mechanism. Another form of the mechanism is
to make the distance from the fixed centre of the lever to the centre of the crank shaft.
less than the radius of the crank, in this case, instead of oscillating, the lever would
describe a complete circle about its fixed centre, but it would move with a variable
angular velocity, for the purposes of the invention it is arranged so as to have the
greatest angular velocity when the combustible gases are expanding after ignition and
least whilst the gases are being compressed. To make this modification more easily
understood it may be mentioned that this form of the mechanism has been applied to
shaping machines by Sir Joseph Whitworth and is known as Whitworth's quick
return motion. In another form of the mechanism it is proposed to join the crank
pin directly to the lever and in order to enable the fixed centre to accommodate itself
to that motion of the lever which takes place at right angles to the axis of the cylintler
we mount it on the end of a rod which can oscillate to the required extent, the piston
rod is constrained to move so that it coincides with the axis of the cylinder by means
of a suitable slide and crosshead, the end of the lever. is slotted and works to and fro
over a slide block which is attached to the crosshead.
Dated this 23rd day of September 1886.
BENJAMIN BUTTERWORTH.
JOSEPH BUTTERWORTH.

page_text: the ignition and Expansion of a Combustible Mixture.
We, BENJAMIN BUTTERWORTH of 16 Casson Gate Rochdale in the county of
Lancaster Engineer, and JOSEPH BUTTERWORTH of 16 Casson Gate, Rochdale in the
county of Lancaster Engineer do hereby declare the nature of this invention and in
what inanner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
This invention is applicable to those engines in which the power is obtained by the
ignition and expansion of a combustible mixture, its object being to quicken the speed
of the piston during that portion of the cycle of operations, in which the combustible
mixture is ignited and expanded, thus lessening the time during which the hot gases
are ignited and expanded, thus lessening the amount of heat which passes through the
cylinder walls and is lost. This first part of the invention is applicable to both
compression and non compression engines, but for compression engines the same
mechanism also retards the motion of the piston during that portion of the cycle of
operations in which the combustible mixture is compressed, thus enabling the engine
to be turned with ease when starting and doing away with the need of self starting
mechanism. In the following description where the outward stroke of the piston
is mentioned it is intended to mean that stroke of the piston in which the combustible
mixture is ignited and expanded and where the inward stroke of the piston is
mentioned it is intended to indicate that stroke of the piston in which the combustible
mixture is compressed. The invention is carried into effect by changing the
reciprocating motion of the piston into the circular motion of the crank shaft by means
of a combination of slit or other lever or link, and crank of such proportions that the
piston performs its outward stroke in much less time than the inward stroke, in a
similar manner to the quick return motion as applied to small planing and shaping
machines. The crank pin of the engine works in a slot or groove in a lever which
oscillates about a fixed centre, this fixed centre is placed on one side of the crank shaft
in such a position that the crank pin is nearest to it during the time the piston is
making its outward stroke in which the gases are ignited and expanded, and
considerably further from it during the time the piston is making its inward stroke,
in which the gases are compressed. The piston rod may be jointed to any suitable
part of the lever but it is preferred to place the centre of the cylinder in line with the
centre of the crank shaft as in an ordinary engine, and to connect the piston rod to
such part of the lever as will enable it to coincide as nearly as possible with the axis

page_text: of the cylinder in working. The lever may, however, be prolonged beyond the fixed
centre, and the piston rod be jointed to any suitable part of the prolongation, in this
case the crank shaft would be on one side of the fixed centre and the cylinder on the
other somewhat similar to a beam engine; the lever may be modified by making it a
plain bar of uniform section and connecting it to the crank pin; by means of a ferrule
made so as to slide along the lever, the action being exactly similar to that of the
slotted lever. The mechanism may be also modified by jointing the crank pin
directly to the lever, the lever in that case sliding through a ferrule at the fixed centre
or the lever might be slotted and work to and fro over a slide block the centre of
which coincides with the fixed centre, the piston rod in this case may be connected to
any suitable part of the lever as in the first form of the mechanism. In another form
of the mechanism it is proposed to joint the crank pin directly to the lever, and in
order to enable the fixed centre to accomodate itself to that motion of the lever and
crank pin which takes place at right angles to the axis of the cylinder I mount it on
the end of a rod which can oscillate to the required extent. The piston rod is
constrained to move so that it coincides with the axis of the cylinder by means of a
suitable slide and crosshead, the end of the lever is slotted and works to and fro over
a slide block which is attached to the crosshead.
In order that the description of the invention may be clearly understood
reference may be had to the accompanying sheet of drawings. Figs. 1 and 2
show the form of the mechanism as preferred by us and are shown in section for
the purpose of explaining its action as clearly as possible. The drawings 3 and 4,
are diagrammatic sketches showing modifications of the mechanism which may be
made to suit various forms of engines. As the different parts of the mechanism are
present in each case, the same lettering is used for similar parts in each drawing.
Fig. 1 represents an engine to which the first modification of the mechanism described
in the specification has been applied. a is the working cylinder in which works the
piston which piston is connected to the crank e by means of the connecting rod d,
lever e, and sliding block of pedestal. The lever e which produces the quick outward
stroke of the piston oscillates about the fixed centre g, which may be fastened to the
bed as shown or in any other suitable manner. It may be of a channel shaped
section as shown in fig. 2. (which is a section of the lever e, crank pin e' and
pedestal along the line ay fig. 1) or of any other suitable form, and has a slot or
groove formed in it preferably of the form shown in fig. 2, for the purpose of allowing
the sliding block or pedestal in which the crank pin c¹ works to slide in it, and it is
connected to the outer end of connecting-rod d by means of the joint h. The crank
revolves in the direction shown by the arrow marked on the crank circle, and as the
sliding block is fastened to the crank pin it is carried round by it, the motion of the
crank pin at right angles to the axis of the cylinder causing it to slide along the slot
or groove in the lever, while the motion of the crank pin in the direction of the axis
of the cylinder is transmitted by means of the lever è and connecting rod d to the
piston causing it to work to and fro in the cylinder a. If the crank pin c¹, which is
constrained to move with a uniform velocity by means of a flywheel revolves in the
direction of the arrow the sliding block will be carried by the motion of the crank
pin to the end of the lever e furthest from the fixed centre y during the inward stroke
of the piston and thus cause the lever e to move with diminished angular velocity.
during that stroke. But the piston is connected to the lever e by means of rod d, and
jointh, which joint is at a fixed distance from the fixed centre y ; therefore the
piston velocity will be sensibly proportional to the angular velocity of the lever e when
working as shown in the drawings and as the velocity of the lever is reduced during
the inward stroke of the piston b, the velocity of the piston will also be reduced to a
proportionate extent. As the crank pin continues to revolve it will cause the sliding
block to slide along the lever towards the fixed centre g during the outward stroke
of the piston b, thus causing the lever to revolve with increased angular velocity during
the outward stroke and increasing the velocity of the piston to a proportionate extent,
and as the combustible mixture is expanded during the outward stroke of the piston,

page_text: it will be expanded more rapidly owing to the quickened speed of piston produced by.
the mechanism during the outward stroke; while during the inward stroke of the
piston, if the mixture be compressed as in a compression engine the piston having a
reduced velocity as before mentioned owing to the crank pin e¹ having an increased
leverage over the piston b, it will cause the person who is revolving the crank shaft
when starting the engine to do so more easily than if the crank pin was attached
directly to the piston as in an ordinary gas engine. In practice the distance traversed
by the slide block f along the lever e bears such a proportion to the distance between
the centre of the crank shaft c and the fixed centre g, as to cause a considerable
difference in the speed of the piston during the outward and inward strokes of the
piston respectively, the difference in speed being such that the piston accomplishes its
outward stroke in not more than about half the time than it accomplishes its inward
stroke as shown on the drawings. In fig. 1 the crank shaft is shown in line with the
axis of the cylinder, but it will be convenient in some cases to have it otherwise, for
instance in the form of the mechanism shown in fig. 3 the lever e is prolonged beyond
the fixed centre and the piston rod is then jointed to some suitable part of the
prolongation, this arrangement will then be similar to a beam engine and the axis of
the cylinder will require to be moved so as to coincide as nearly as possible with the
motion of that part h, of the lever to which the piston rod is jointed as shown.
The lever e may be modified by making it a plain bar of uniform section, the sliding
block would then have a ferrule fastened to it having a hole through of same size
and shape as the section of the bar so as to allow it to slide along the lever as before.
The mechanism may also be modified by jointing the crank pin e'directly to the lever e
as shown in fig. 4 the lever in that case being a bar of uniform section and sliding
through a ferrule at the fixed centre g, or the levere may be slotted as shown and
work to and fro over a slide block whose centre coincides with the fixed centre the
piston rod d being connected to the lever e by joint as in the previous forms of the
mechanism described. In another form of the mechanism it is proposed to joint
the crank pin c¹ directly to the lever e, and in order to enable the fixed centre 7 to
accomodate itself to that motion of the crank pin at right angles to the axis of the
cylinder we mount it on the end of a rod which can oscillate to the required extent.
The piston rod d is constrained to move in a line with the axis of the cylinder by
means of a suitable slide and crosshead. The end of the lever is slotted and works to
and fro over a slide block which is attached to the crosshead.
Having thus described our invention we wish it to be understood that we do not
claim the use of a slit lever motion of any dimensions whatever but what we do
claim is
1st. A slit or other lever in which the distance traversed by the sliding block
along the lever e bears such a proportion to the distance between the centre of the
crank shaft c and the fixed centre g as to cause a considerable difference in the speed
of the piston during the outward and inward strokes of the piston respectively, the
difference in speed being such that the piston accomplishes its outward stroke in not
more than about half the time that it accomplishes its inward stroke, substantially as
and for the purposes described.
2nd. The arrangement of slit lever motion as shown in figs. 1 and 2, and having the
proportions mentioned in first claim substantially as and for the purposes herein
described.
3rd. The modification of the mechanism as shown in fig. 3, in which the lever
having the proportions as mentioned in first claim is prolonged beyond the fixed
centre substantially as described.
4th. The modification of the mechanism wherein the lever is made a plain bar of
uniform section, and the slide block slides along it by means of a ferrule attached to
the slide block substantially as described.
5th. The modification of the mechanism shown in fig. 4 whereby the end of the
lever e is jointed directly to the crank pin, and the lever accomodates itself to that

page_text: motion of the crank pin at right angles to the axis of the cylinder by sliding over the
fixed centre y substantially as shown and described.
6th. The modification of the mechanism in which the crank pin is jointed directly
to the lever e and the fixed centre g, is fixed on the end of an oscillating rod in order
to allow it to accomodate itself to that motion of the crank pin at right angles to the
axis of the cylinder, while the end of the lever is slotted and works over a slide block
attached to the crosshead as described.
7th. The construction, arrangement and combination of a slit or other lever, crank,
and piston (in a compression or noncompression engine) of such proportions that the
stroke in which the combustible mixture is ignited and expanded is accomplished in
not more than about half the time that is occupied by the stroke in which the gases
are compressed or exhausted, substantially as and for the purposes herein described.
Dated this 23rd day of June 1887.
BENJAMIN BUTTERWORTH.
JOSEPH BUTTERWORTH.