Improvements in Gas Engines and Igniters for the same.
Year: 1889

page_text: Date of Application, 17th Dec., 1889-Accepted, 28th Dec., 1889
COMPLETE SPECIFICATION.
Improvements in Gas Engines and Igniters for the same.
We, WILLIAM EDWARD CRIST, of Brooklyn, in the State of New York and
United States of America, Machinist, and HIRAM CORNELIUS COVERT, of New York,
in the State of New York, and United States of America, Gentleman, 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 pertains to that class of motors which are driven by the explosion
of a gas or gaseous compound produced by means of a suitable igniting-device, and
relates to the construction of an engine of this type with vibrating-pistons and to
an improved igniter for use therewith as hereinafter fully described and claimed.
It has for its object to simplify the construction of such a motor and its igniting
device, and to render the same more compact, reliable and efficient.
In the accompanying drawings:-
Figure 1, is an end view of our improved vibrating gas-engine showing one half
thereof in central section.
Figure 2, is a side view, half in section in line of Figure 1.
Figure 3, is a detailed view in elevation of the improved igniters by which the
explosive charge in each working-chamber is fired at the proper moment, and of the
mechanism for actuating the same, the driving shaft being in section.
Figure 4, is a transverse section on an enlarged scale of one of the igniters taken in
the line y-y of Figure 3.
of
Figure 5, is a detailed, central, vertical section of the same in line
Figure 4 the piston being shown in elevation and as at the outer end of its stroke.
Figure 6, is a corresponding section showing the same piston at the inner end of
its stroke.
Similar letters and numerals indicate for reference like parts in all of the Figures.
A, Figures 1 and 2, represents a segunental-casing formed integrally with, or secured
upon, a suitable base B, parallel with its axis.
A portion of the casing, embracing an arc of about 90 degrees more or less, is
wholly removed at the top thereof leaving it entirely open. Its ends are closed by
end-plates or heads C, C¹, securely bolted thereto.
These heads furnish bearings for a shaft D, extending longitudinally through the
casing in coincidence with its axis. This shaft is mounted to rock in its bearings
and is fitted with two radial plates D³, and D2, which extend the entire length of the
inside of the casing so as to make a close joint with the inner face of each of its
heads, and they project radially from the shaft in opposite directions far enough to
contact at their outer edges with the inner periphery of the casing. These radial
plates are preferably formed in the same diametric plane, and in one piece with the
axial shaft D, and in combination therewith constitute the oscillating pistons of the
engine. The joints between the walls of the casing and the piston are packed by
means of metallic, spring-seated packing strips a, a, inserted in longitudinal grooves
in the ends and edges of each piston to bear outwardly in the customary manner
against the walls.
A crank-shaft E, is mounted above the casing A, parallel with the piston-shaft D,
in suitable bearings in the two heads C, C, which are extended far enough for the
purpose, and a crank formed in the shaft E,-preferably midway the length of the
casing, by means of two discs E', E', and a transverse pin i, see Figure 2,-is
coupled by a connecting rod E' to one of the piston-plates D'. Hence the oscillation
of the piston is made to produce a rotation of the crank-shaft and the crank is so
proportioned with reference to the radial distance of the connection of the rod E
with the piston, from the axis of the piston, as that a revolution of the crank is

page_text: produced at each oscillation of the piston over an are of about 90 degrees more
or less.
The inner portion of the casing is divided longitudinally by partition-walls F. F,
which extend from the end thereof and radiate from the inner side of the piston
shaft D to the inner periphery of the casing, at a divergent angle with each other of
about 90 degrees; and the pistons are so adjusted in their connection to the crank E¹
as that when the inner face of either piston is brought up closely against the proximate
partition-wall F, the crank will be on a dead centre. In the movement of the engine
the crank is carried past its dead-contre in the customary manner by the momentum
of a fly-wheel E, fixed upon the crank-shaft E.
The piston-shaft D is confined and supported throughout its length within the
casing between the apex of the diverging partition-walls F, F, on one side and the
edge of a parallel bar F, mounted on the diametrically opposite side thereof and
whose ends are fixed in the ends of the casing. This bar F', serves also to strengthen
the casting and to prevent the hot-air discharged from the one piston-chamber from
being carried over into the other,
The joints between the shaft and said longitudinal supports are severally packed
by means of spring-scated packing strips a', or other equivalent packing material,
fitted in longitudinal grooves in the partition and the supporting-bar.
The sectoral space included within the casing next to the base B, between the
radially-liverging partition-walls F, F, and the inner periphery and ends of the casing.
constitutes the compression-chamber H of the engine.
A vibrating-piston G, is mounted in said chamber, being made to project therein
from a rock-shaft G₁ fitted in the inner central angle of the chamber and made to
oscillate in suitable bearings formed in the heads C, C, of the casing.
The edges of this piston are packed to maintain a close joint with the inner walls
of the supply-chamber as they move over it, and the rock-shaft G, is also packed in
its longitudinal sent so as to prevent a leakage from the one side to the other.
The two outer corners or angles of the supply-chamber H are made to communicate,
each by nicans of an extended port H, with a cylindrical valve-chamber I, formed
within the base B, to extend from end to end thereof, and within which is fitted
closely a cylindrical, tubular valve-piece J. This valve-piece J, is formed with a
longitudinal partition or septum therein extending from end to end thoreof dividing
it into two unequal chambers the larger of which is left open and the smaller closed at
each end. The longitudinal septum is longitudinally-slotted to form a narrow slit
or valve-opening e, communicating with the larger, open-ended chamber for a
length about equal to that of the port H. This valve-opening is closed automatically
by a weighted or spring-actuated flap-valve K, fitted in the smaller closed chamber
and hinged at one edge to the face of the septumn to extend over and close upon the
valve-opening c. A second, longitudinal, cylindrical passage or bore d is provided in
the valve-piece J under the hinge of the valve K, and a small, narrow, longitudinal
slot e, is pierced intermediate the valve-opening r, and the hinge of the valve K, to
communicate with said cylindrical passage and be covered and closed by the valve.
The cylindrical passage or bore d, is closed at one end and connected at the other
with a gas-sapply pipe d', so that whilst a supply of air will he admitted to the
port H, through the open ends of the enlarged chamber under the valve K, when the
valve is lifted, a supply of gas will be simultaneously admitted through the bore d.
An inner tube, may be fitted within the bore d, to admit of rotation therein, and
he longitudinally perforated to serve as a valve to control the slot e, and thereby
regulate the delivery of gas through the same as the perforations are brought into
more or less complete registry with the slot by a rotation of the tube . This
rotation may be effected by means of a governor attached to the engine.
By withdrawing the valve-piece J from its seat in the valve-chamber I, the valve K
may be readily reached for repair or renewal. The open ends of the valve-piece may
be protected by wire-screens T-as shown in Figure 1.
A narrow extended port L, is formed centrally through each of the partition
walls F, F, to establish communication between the compression-chamber H and each

page_text: working-chamber and each of said ports L, is covered by a suitable spring-actuated
poppet-valve L', adapted thereto and which is seated in the working-chamber and is
guided by a suitable stem passing through a cross-bar in the port. The spring for
automatically closing the valve, is preferably fitted within the port L, and may consist
of an elastic plate 1, attached centrally to the valve-stem and whose ends shall
engage the walls of the port, the spring-plate being perforated to present the least
possible obstruction to the flow of the gases through the port.
The outer end of the rock-shaft G carrying the compressing-piston G, is fitted
with a crank-arm G' which is coupled by a connecting-rod G³, to a wrist-pin S, upon
the fly-wheel E³, on the crank-shaft E, so that the revolution of said shaft shall
produce an oscillation of the compressing-piston G in synchronism with the move-
ments of the driving-pistons D' D³. The wrist-pin S, is so adjusted with reference to
the crank-arm G and to the crank E' coupled to the driving-piston, as that the
compressing-piston G, shall invariably move in the direction opposite to that of the
working-piston which is at the time heing driven by the force of an explosion. This
movement of the compressing-piston will operate to draw in behind it into the
compression-chamber through one of the induction ports H', a supply of air or gas,
and to drive and compress the admixed air and gas constituting the explosive charge,
towards the working-piston which is moving towards it in the working-chamber.
The explosive-charge is retained in the compression-chamber by the resistance of the
spring L actuating the valve I, until the approaching piston in the working-chamber
lias completed its stroke towards the valve and has commenced its return, the burnt gases
in front of said working-piston being in the meanwhile freely discharged as it advances,
through an exhaust-port Q in the casing A, opening outwardly from the inner, outer
angle of each piston-chamber.
'
Each exhaust-port Q, is controlled, as shown in Figure 1,. by a valve M, carried
upon an arm projecting from a rock-shuft M' which is positively operated in
synchronism with the movement of the compressing-piston G, by means of a crank-
arm M on its outer end, conpled by a connecting-rod N with a corresponding crank-
arm N¹ on the end of the shaft G₁ carrying said piston, said arms being so adjusted with
reference to the compressing-piston G, and allowed to have so much lost motion
each by means of a longitudinal slot Y, therein, see Figure 1, as that each exhaust-
valve M shall close just before said piston has completed its stroke and has so far
compressed the explosive charge before it as to force open the valve L' against the
stress of its spring.
After the exhaust-valve has closed, so much of the burnt gas as may still remain in
the working-chamber is compressed and driven into the exhaust-port Q, and the space
in front of its valve M; so that, as the working-piston begins to make its return
stroke, the explosive charge entering through the valve I will alone fill the space
under the inner face of the piston.
At the instant the explosive-charge enters the working-chamber under the piston
therein it will be exploded by the action of the igniting-device.
This igniting-device may be of any of the approved forms now well known to that
art, to be rendered effective by the use either of a gas-flame or by means of an
electric spark. Practically the novel form of igniter illustrated in Figures 3 to 6,
of the accompanying drawings and hereinafter described, has proven to be exceedingly
efficient.
A separate igniter is preferably connected with each of the piston-chambers.
As the compressing-piston begins its return stroke at the moment it has fully
driven the explosive charge into the working-chamber, the valve L³ is thereupon at
once relieved and will instantly close.
The working-chambers are encircled by a water-jacket R, formed within the walls
of the casing in the customary manner, the several water spaces being connected by
transverse passages in the heads of the casing adapted to facilitate a circulation of
water in the jacket. The water supply is admitted through inlet-ports R¹, R', in the
lower part of each head, from which it flows and circulates through the several spaces

page_text: of the water-jacket and is discharged through central outlets R³, R2, in the upper part
of the casing on each side thereof.
As the working-chambers are opened freely to the air on the outer side of the
pistons the currents of air which follow the pistons as they are carried inward and are
expelled again by their outward movement, will assist greatly in cooling the walls of
said chambers.
In the operation of this form of the improved motor, by turning the shaft E so that
it shall make ono revolution, the compressing-piston G will, during the first half of
said revolution, draw a charge of air admixed with a due proportion of gas, through
the inlet-port H¹ into the compression-chamber H, and, during the remainder of the
revolution, will by its return stroke, compress said charge.
In the meantime, the working-pistons are made to move simultaneously with the
compressing-piston in directions opposed thereto so that, as the latter drives and
compresses the charge of admixed air and gas towards either port L in the compression-
chamber communicating with either working-chamber, the piston in said working-
chamber will be carried towards the same port. During this movement of the
working-piston the exhaust-valve G will be open and will allow a free exhaust of the
air or burnt-gases from in front of the piston until the stroke of the piston is nearly
completed, whereupon the exhaust-valve will be closed in manner as described. The
remainder of the stroke of the piston will then compress so much of the air and burnt
gas as remains, out into the exhaust port Q.
As the compressing-piston compresses the charge in the compression-chamber, the
spring which governs the valve I towards which the piston is moving, will operate
to retain and confine the charge in said chamber against the stress of the advancing
piston. The power of the spring to hold the valve L' closed, and thus confine the
compressed charge, will be reinforced so soon as the exhaust-valve is closed, by the
pressure of the air and gas in the working-chamber upon said valve L' effected by
the advance towards it of the working-piston as it completes its stroke. So soon
however as the piston begins its return stroke so as to diminish this pressure, the
valve L', relieved therefrom, will no longer resist the pressure of the charge and will
fly open against the stress of its spring and, as the compressing-piston completes its
stroko, the charge will be wholly carried into the working-chamber and be thereupon
instantly ignited and exploded to exert its full force against the receding working-
piston, which, as the crank will have then fully passed the dead-centre, "will be in
position to act most effectively upon the crank. To render this delivery of the
explosive charge into the working-chamber prompt and effective, the compressing-
piston is so geared as that it will move with its greatest rapidity at the end of its
stroke in each direction occuring after the exhaust valve has been closed, the working-
piston at the same time making its slowest movement.
So soon as the explosive charge has thus been discharged into the working-cylinder,
the valve L' will, under the stress of its spring, automatically close, being relieved
from pressure on its inner side by reason of the return movement of the compressing-
piston which begins at this moment.
The exhaust-valve will remain closed during the entire outward stroke of the piston
but will open so soon as the stroke is reversed to allow a free vent for the burnt
gases during the return, inward stroke.
While one piston is moving outward on one side of the engine under the power
of an exploded charge admitted, compressed and ignited as described, the other
piston is moving inward and discharging the burnt gases by whose explosion it
was carried outwards, the movement of the compressing-piston operating meantime
to compress a fresh charge and to draw in a fresh supply of air and gas in readiness
for compression.
There is thus virtually a continuous application of power in this engine, the
intermissions, more or less frequent, which occur in other forms of gas-engines being
wholly avoided therein.
To produce at the proper moment an explosion of the compressed gases or gaseous

page_text: compound in the engine we have found it preferable to make use of a constantly-
burning igniting-flame in connection with a reciprocating-piston operating as a valve
to control passages extending from the firing-port of the working-chamber, to the
flame-port, and as a carrier to convey at the proper moment an inflamed firing-charge
from the flame-port to the firing-port.
The casing 10 for our improved igniting-device constructed upon this principle,
sco Figures 3 to 6, is made with a central cylindrical bore 11 extending longitu-
dinally through it, and with walls of sufficient thickness to admit of a water-space R³
therein encircling said bore. It is adapted be secured against the outer wall of
the working-chamber of the engine, see Figures 2 and 3, -near to the point at
which the working-charge is to be exploded therein so as to cover the firing-port, 12,
opening into the working-chamber, see dotted lines Figure 2.
An opening or passage, 13, is pierced to establish direct communication between
the firing-port 12 and an annular recess 14 formed about the inner periphery of the
cylindrical bore.
A second opening or passage 15, is pierced in the opposite direction through the
casing 10, from a second annular recess 16 encircling the inner periphery of the
bore at a suitable distance above the first recess 14. This opening 15 constitutes
the flame-port and is preferably made with an upward inclination, as shown in
Figures 5 and 6.
A.small burner 17, connected with a suitable gas-supply pipe 18, is formed or fitted
immediately below the flame-port 15, in position to permit the flame of the burner to
reach said port.
-
A piston or plunger, preferably formed in two sections 19 and 20, to permit of
longitudinal adjustment as hereinafter described, is fitted to work closely yet freely in
the cylindrical bore 11, to establish and to control communication between the internal
recesses 14 and 16.
The inner or lower end of the first or upper section 19, is so reduced in diameter
as to leave, between it and the inner end of the second or lower section 20, an annular
space or recess 21, and it terminates in an extended cylindrical stem 22 adapted to
pass through a cylindrical aperture pierced through the second section, the outer end
of said stem being threaded to allow said second suction to screw upon it and be
thereby adjusted to and from the first, as shown in Figure 6. The edge of the
aperture where it enters the annular recess 2.1, is bevelled to form a conical or
countersunk seat 23, for a counterpart, tapering shoulder formed about the inner end
of the stem 22, so that the two form a valve which will be opened or closed more or
less as the section 20 is adjusted more or less closely to the section 19.
A groove or recess 25, is made to encircle the periphery of the lower section 20 of
the piston at a point so located with reference to the encircling recess 21 between the
two sections and to the passages in the casing leading severally to the flame and
firing ports, as that, when the recess 21 is in register with the firing-port 13,
the recess 25 will be closed, as shown in Figure 6, but, when by a movement of
the piston the recess 21 is in register with the flanie-port 15, the recess 25 will
be in register with the passage 13 leading to the firing-port, as shown in
Figure 5.
The diameter of the stem 22, is so far reduced between the peripheral recesses 21,
and 25, as that a concentric passage 24, is left between the two, and this passage
is made to communicate freely with the groove or recess 25 encircling the
periphery of the piston, by means of a series of radial apertures 26, 26, pierce: in
the section 20.
By this means free communication is established between the flame and firing ports
when the recess 25 is in register with the passage 13, said communication being
governed by the adjustment of the opening at 23, as shown in Figure 5.
When the adjustment of the two sections of the piston to or from each other
by which the area of the opening at 23 is regulated, is properly made, the two
sections are locked together to prevent an accidental variation in said opening-by
means of a lock-nut 27 screwing upon the outer end of the stem 22.

page_text: The firing-piston must necessarily be actuated in synchronism with the
movements of the working-piston of the engine in such manner as that, at the
moment an explosion of the charge is desired, the recess 21 encircling the firing-
piston shall be moved inward from its registry with the flame-port into registry with
the firing-port.
This may be accomplished in several ways which will readily suggest themselves to
a skilled mechanic, but in the engine as now constructed the piston is coupled by a
connecting-rod 28 to one arm of a bent-lever or bell-crank 30,-see Figure 3,-
pivoted to the casing in position to bring its upper arm into contact with the
periphery of a cam-wheel 33, upon the rotating-shaft. The periphery of the
wheol 33, is so formed and proportioned as that it will in its revolution throw
the lever-arm outward to produce a quick drop of the piston and, after a suitable
interval, allow it to move back under the stress of a spring 31 fitted to bear against a
third arm 32 of the lever and operating to hold the lever against the periphery
of the cam.
The lovers actuating the two igniters for the engine may both be operated by the
one cam-wheel 33, as shown in Figure 3.
The connecting-rod 28 is coupled to the firing-piston. This connection is preferably
made by means of a ball-and-socket joint, as shown at 29, in Figure 6, whereby the
piston is protected and relieved from any strain or undue friction and is left free to
move at all times with perfect ease.
In the operation of the igniter constructed as described, the igniting-flame is kept
constantly burning.
By reason of the adjustment of the firing-piston in relation to the working-piston
of the engine as described, the recesses 21 and 25 will, while the working-piston is
making its instroke and the exploded charge is exhausting from the working-chamber,
severally register with the flame-port and with the port leading to the explosion-
chamber, as shown in Figure 5, so that there will be free communication through the
passages in the igniter from the one to the other thereby permitting a full exhaust of
all burnt gases from said passages.
The firing-piston will remain in this position until the working-piston, having
completed its instroke, the explosive charge is admitted. A portion of this charge
under pressure will find vent through the ports 12, 13, and the passages 26 and 24 of
the igniter, to the flame-port 15, where, coming into contact with the flame it
will be ignited and will burn freely in the recesses 21 and 16, into which it
escapes through the circular channel at the valve 23 in an annular, outwardly-
flaring jet.
The tapering form of the valve 23 by producing this annular, flaring jet, so
facilitates the ready outward passage of the gases as that the flow is not easily
broken or interrupted.
So soon as the propor moment arrives in the movements of the engine for an
explosion of the charge therein, the firing-piston, actuated by means of its connection
with the cam upon the engine, is suddenly moved inward, thereby carrying the
recess 21, in which the gases flowing outward under pressure from the explosion-
chamber are burning in an annular jet, into register with the recess 14 and passage 13,
as shown in Figure 6. During this movement the gases confined in the recess 21 and
carried with it to the passage 13, continue to burn, so that, so soon as said passage is
reached, they serve to fire the entire explosive charge in the passage 13 and port 12
and in the working-chamber with which they communicate, and at the same time the
outward vent from said ports through the igniter is cut off.
The firing-piston will then remain in position to cut off all outward vent until the
working-piston has completed its outstroke, whereupon it will be carried outward
again to its first position (Figure 5) in readiness for an exhaust and the reception of
a fresh igniting-charge.
The longitudinal adjustment of the two sections 19 and 20 of the firing-piston upon
a common axis, permits the escape of the igniting-charge in the annular-recess 21 to
be readily controlled and determined at pleasure in proper relation to the degree of

page_text: compression of the explosive-charge, and the peculiar form of said recess ensures the
transfer of the igniting-charge in its inflamed condition from the flame-port to the
exploding-port in the movement of the firing-piston without danger of its extinguish-
ment before the explosive-charge is fired theroby.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what wo
claim is-
-
1. The combination in a gas-engine, of a working-piston vibrating in a sectoral
working-chamber, a compressing-piston vibrating in a separate sectoral compression-
chamber and operating to compress and carry an explosive gaseous charge towards the
working-piston as it advances, a spring-controlled valve governing a port or passage
connecting the supply and working-chambers and opening towards the latter, an
igniting-device communicating with the working-chamber and operating to fire the
charge compressed therein at the end of the stroke of the piston towards said charge,
and means for discharging the burnt gases, all substantially in the manner and for
the purpose herein set forth.
2. The combination in a gas-engine, of sectoral working and compressing-chambers
constructed and arranged substantially, as described; oscillating pistons vibrating
in each chamber valves disposed to govern supply-ports opening into the opposite
ends of the compression-chamber to admit an explosive gaseous compound thereto
alternately on opposite sides of its piston; delivery ports or passages connecting
appropriately each end of said chamber with the working-chamber and governed by a
valve opening towards said working-chamber; an igniting-device operating to fire the
charge compressed into the working-chamber at the end of the stroke of the piston
towards said charge; and means for the discharge of the burnt gases, all substantially
in the manner and for the purpose herein set forth.
3. The combination in a gas-engine, of a central rock-shaft; sectoral working-
chambers formed on opposite sides thereof and provided with exhaust-valves at
their inner ends; oscillating pistons fixed to the shaft to vibrate in said working-
chambers; a parallel driving-shaft; a crank upon said shaft coupled to one of said
pistons; a sectoral compression-chamber intermediate the working-chambers, having
supply valves at each end thereof; a second rock-shaft mounted parallel with the
first in the inner angle of said compression-chamber; a compressing-piston fixed
therein to vibrate in the compression-chamber; coupling devices connecting the
driving-shaft and second rock-shaft in manner to cause the compressing-piston
to advance towards the working-pistons as they move inward and recede therefrom
as they move outwards; means as described for opening each exhaust-valve as the
piston begins its inward stroke and closing it immediately before the stroke is
completed; and igniting-devices whereby the charge compressed under each working-
piston at the end of its inward stroke is fired, substantially in the manner and for
the purpose herein set forth.
4. The combination with the supply-port for gas and air in a gas-engine, and with
a cylindrical valve-chamber communicating with said supply-port, of a tubulur valve-
piece fitting in said valve-chamber and which is longitudinally divided by a flat septum
into two longitudinal spaces communicating with each other by means of a longitudinal
aperture in the septum, one of said spaces being left open peripherally and closed at
its ends by transverse end-plates, and the other left open at its ends only to com-
municate freely with the outer air, said valve-piece having also a separate cylindrical
bore formed longitudinally in an enlargement of its wall in one of the angles of the
open-ended space, this bore being closed at one end and made to communicate through
an aperture in the septum with the valve-space whose ends are closed; a gas-supply
pipe fitted to the open end of the bore; and a valve fitted upon the septum to close
down upon the apertures therein, substantially in the manner and for the purpose
herein set forth.
5. The combination in an igniting-device for gas-engines constructed substantially

page_text: as herein described, of a piston reciprocating in a suitable casing and having a con-
centric passage formed longitudinally within it communicating at one end with an
aperture flaring outwardly to the periphery thereof and at the other end with radial
passages extending likewise to its periphery; a flame-port communicating through
the casing with the annular flaring-aperture; a second port connecting the explosion-
chamber of the engine with the radial passages; and a burner placed adjacent to the
flame-port to supply an igniting-flame therefor, substantially in the manner and for
the purpose herein set forth.
6. An igniting-device for gas-engines constructed substantially as herein described,
of a suitable casing having a longitudinal passage-way through it communicating by
transverse passages at different points in its length with a flame-port and with a port
to communicate with the explosion-chamber of the engine; a controlling piston
playing in said passage-way, said piston being formed in two sections adjustable upon
its longitudinal axis to and from each other, leaving a circumferential recess betwech
them adapted to register with the flame-port, and having also a second peripheral
recess upon one of the sections adapted to register with the port from the explosion
chamber; and a connecting passage extending from the one recess to the other,
substantially in the manner and for the purpose herein set forth.
Dated thin 17th day of December 1880
ALLISON BROS.,
Agents for the Applicants.