Improvements in and relating to Gas or Explosive-vapour Motor Engines.
Year: 1893

page_text: Date of Application, 20th Jan., 1893
Complete Specification Left, 20th Oct., 1893-Accepted, 20th Jan., 1894
PROVISIONAL SPECIFICATION.
Improvements in and relating to Gas or Explosive-vapour Motor
Engines.
We PETER BURT and GEORGE MCGHEE both of Mountblue Engineering
Works, Glasgow, Lanarkshire, Scotland, Engineers do hereby declare the nature
of this invention to be as follows:-
This invention has for its object to provide an economical and efficient high-
speed single acting gas motor engine by having its principal working parts always
in compression so as to avoid knocking or back-lash; to provide means for
making engine self-starting; and means whereby the engine may be worked in either
direction; as also means to facilitate the renewal of igniting tube; and lubricators
for use under pressure in gas engines.
The engine has two cylinders with pistons, mounted tandem system to each other,
one connecting rod and crank serving for each set of tandem cylinders, which set of
cylinders cranks &c. may be duplicated if desired. It is preferred that the cranks
work in an oil chamber forming part of the engine seat. To avoid stuffing or glands
between the two cylinders the motor piston rod has a small piston thereon working
in a liner or cylinder between the two cylinders which closes the top of 1st cylinder;
the bottom of both cylinders being preferably open to the atmosphere. Each
cylinder has a valve case, in each of which work two pressure balanced piston valves
wrought by one or two rods and eccentrics on a shaft driven at half the speed of
crank shaft. The valve case has or may have an air cushioning chamber to keep
the valve rod always in compression. The said valve cases have ordinary gas and
air supply valves, the gas valves being actuated by an oscillating lever wrought by
an eccentric on valve shaft. The cycle of operations of each motor cylinder is that
of Beau de Rochas or Otto; but while the motor piston of one cylinder is on the
impulse outstroke the piston of the other is on the charging or mixture inhaling out-
stroke. The crank has thus an outward impulse every revolution. As one of the
two pistons on the upstroke is (in regular work) always compressing its charge the
connecting rod is under compression which tends to prevent back-lash or knocking
of brasses.
The engine to be self-starting has a compressed air reservoir communicating with
either of the motor cylinders (the gas being shut off from engine when it is to be
started). In the passage between the cylinder and reservoir is a non-return valve
which retains the air pumped thereinto, or the pressure generated by part of the
products of combustion when charge is exploded. Otherwise, live steam may be
used in lieu of air. On the eccentric shaft is a double cam or, on the crank shaft a
single cam to actuate the air or steam inlet or non-return valve at the beginning of
every motor piston outstroke thus driving out the piston. At the end of stroke the
air escapes through a supplementary exhaust port in the valve case every alternate
stroke and through ordinary exhaust port every other alternate stroke.
supplementary port is shut by a cock or valve when engine is started and to be
worked by gas; or when being used as a pump or air compressor, both exhaust
ports may be shut to allow of reservoir being charged. The aforesaid cam is put
out of gear with the valve before the supplementary exhaust port is closed.
The
To allow of the engine working in either direction the respective eccentrics and
cams are mounted on a sleeve loose on valve shaft which sleeve can be set back or
forward on said shaft for the engine to work in either direction.
In order to enable the igniting tube being renewed while engine is working;
in the passage from the hot-tube to the valve casing a small valve or pin is fixed,

page_text: which when screwed up closes the communication between the tube and casing
when the tube being renewed, which said valve or pin is opened when tube is
fixed.
To provide for the efficient lubrication of gas engines the lubricator consists of
an air-tight oil vessel to the top of which opens a channel or pipe communicating
with the inside of cylinder just behind the piston when full out, so as to admit some
of the compressed products of combustion to enter above the oil and drive it
through another pipe to desired point to be lubricated. Stop cocks are or may be
provided on each pipe.
Dated this 19th day of January 1893.
DAVID F. MASON, C.E.,
Glasgow, Patent Agent.
Improvements in and relating to Gas or Explosive-vapour Motor
Engines.
We PETER BURT and GEORGE MGHEE both of Mountblue Engineering
Works Glasgow, Lanarkshire Scotland, Engineers, 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 relates to improvements in gas or explosive vapour motor
engines, the main objects being to construct an economical and efficient high speed
single acting gas motor engine having its principal working parts always in
compression so as to avoid knocking or back-lash; to provide means for starting
engine; and to facilitate the renewal of igniting tubes while engine is working, as
also to construct an efficient self acting gas engine cylinder lubricator.
The engine has two cylinders with pistons mounted tandem system to each other,
one connecting rod and crank serving for each set of tandem cylinders, which set
of cylinders, crank &c., may be duplicated if desired. It is preferred that the
cranks work in an oil chamber forming part of the engine seat. To avoid stuffing
or glands between the two cylinders, the motor piston rod has a small piston
thereon, working in a liner or cylinder between the two cylinders, which closes the
top of 1st cylinder, the bottoms of both cylinders being preferably open to the
atmosphere. Each cylinder has a valve case, in each of which works a valve
comprising two pressure balanced piston valves wrought by one or two rods and
eccentrics on a shaft driven at half the speed of crank shaft. The valve case
has, or may have an air cushioning chamber to keep the valve rod always in
compression.
The said valve cases have ordinary gas and air supply valves, the gas valves
being actuated by an oscillating lever wrought by an eccentric on valve shaft.
The cycle of operations of each motor cylinder is the two revolution or Beau de
Rochas, or Otto, but while the motor piston of one cylinder is on the impulse
outstroke the piston of the other is on the charging or mixture inhalating outstroke.
The crank has thus an outward impulse every revolution. As one of the two
pistons on the upstroke is, in regular work, always compressing its charge, the
connecting rod is under compression which tends to prevent back-lash or knocking
of brasses.
The engine, to be self starting, is combined with a compressed air reservoir
communicating with either of the motor cylinders, the gas being shut off from
engine when it is to be started. In the passage between the cylinder and the
reservoir is a non-return valve, which retains the air pumped thereinto, or the
pressure generated by part of the products of combustion when charge is exploded.
Otherwise in lieu of air, live steam may be used. On the eccentric or valve shaft

page_text: is a double cam, or on the crank shaft a single cam to actuate the air or steam inlet,
or non-return valve at the beginning of every motor piston outstroke thus driving
out the piston.
At the end of stroke the air escapes through a supplementary exhaust port in
the valve case, every alternate stroke and through ordinary exhaust port every
other alternate stroke. The supplementary port is shut by a cock or valve when
engine is started and to be worked by gas; or when being used as a pump or air
compressor, both exhaust ports may be shut to allow of reservoir being charged.
The aforesaid cam is put out of gear with the valve, before the supplementary
exhaust port is closed.
In order to enable the igniting tube being renewed, while engine is working, in
the passage from the hot tube to the valve casing a small valve or pin is fixed,
which when screwed up closes the communication between the tube and casing when
the tube is being renewed, which said valve or pin is opened when tube is fixed.
To provide for the efficient lubrication of the motor pistons of gas engines, the
lubricator consists of an air tight oil-vessel, to the top of which opens a channel or
pipe communicating with the inside of cylinder, just behind the piston when full
out, so as to admit some of the compressed products of combustion to enter above
the oil, and drive it through another pipe to desired point to be lubricated. Stop
cocks are, or may be, provided on each pipe.
And in order that our said invention may be properly understood we now proceed
more particularly to set forth the system, mode, or manner in or under which the
same is, or may be, used, or practically carried into effect reference being had to
the accompanying drawings.
DESCRIPTION OF THE DRAWINGS.
Fig. A of the annexed drawings is a vertical section on the lines y. z. of Fig. A',
of an engine constructed according to this invention; Fig. A' a reduced diagramatic
part plan, and Fig. B, a back elevation thereof. The other figs. illustrate details
hereinafter described.
Like reference numbers or letters refer to like parts throughout the drawings.
Referring to Figs. A and B of the drawings, the engine comprises two
cylinders 1, 2, mounted tandem system or concentric to each other, the piston rod 18,
pistons 19 and 20, connecting rod 4, crank and shaft 5, serving for each set of
tandem cylinders. The extended part 6 of outer casing of cylinder 2, has two
opposite manholes and doors i, and is fixed to engine bed or seat 7 which serves as
an oil bath for crank 5 to work in, all in usual way. The top and bottom flanges 11,
of cylinder casings 1 and 2 are bored and truly fitted water tight with liners 1*, 2*,
which, with the casings form the water jacketed motor cylinders. Part of aforesaid
casings 1, 2, are formed bulged out and with flanges 13, which are also accurately
bored and fitted water-tight with liners 14, 15 thus constituting water jacketed
valve cases. The two cylinder cases 1, 2 are bolted together with the hollow
cover 16 for cylinder 2 between them, which cover is formed with two or more
water ways 17 for the cooling water to circulate into said cover and jackets 1, 2,
round the cylinder and valve liners; the water being supplied thereto in usual
way.
To avoid stuffing boxes or glands between the two cylinders the tail motor piston
rod 18, is fixed into the two motor pistons 19, 20, concentric therewith, by screw
nuts in usual way, and is made of sufficient diameter to slide easily within the
liner 21 with as little clearance as practicable and formed with three or other
number of grooves, into which are fitted ordinary flexible or expanding packing
rings 22 so as to make the rod 18 capable of reciprocating inside liner 21 practically
fluid-tight, thus dispensing with a stuffing box and gland. Otherwise said rod may
be made thinner and with a piston thereon as indicated by dotted lines and having
grooves fitted with packing rings as aforesaid. The hollow cover 16 is formed as
shewn with the ends sufficiently far apart to correspond to length of stroke of tail
rod 18, and is bored and accurately fitted water-tight with liner 21 which is kept

page_text: cool, when engine is working, by the surrounding water. The bottom of cylinder
casing 1 and piston 19 are open to the atmosphere, said casing being formed with
ribs d waterways 17, and flange e Figs. A. and B. by which it is bolted to cover 16
and top of casing 2, leaving air passages f Fig. B. to inside of cylinder. The
bottom casing has likewise air passages (not shewn) to bottom of piston 20. Each
of the valve liners 14 and 15 is fitted with a balanced piston valve consisting of
the larger piston g, which regulates the passage through the ports and the balancing
piston, which are each fitted with packing rings to keep them fluid-tight while
working, the fluid pressure acting equally on inner ends of both said pistons,
counterbalancing each other. As shewn at Fig. A all the pistons g. are fixed on
same valve rod which is attached at one end to, and reciprocated by connecting
rod k and eccentric on valve shaft m. Said valve shaft is revolved in ordinary
bearings in engine frame 6 at half the speed of main shaft 5 by means of the usual
two to one spiral gearing (not shewn) the shaft m lying at right angles to shaft 5
all in well known manner to suit the ordinary 4 stroke or Otto cycle. In order to
keep the valve and connecting rods j, k, always in thrust so as to avoid knocking,
the top of valve liner 14 is fitted with a cover n thus forming an air cushioning
chamber against the air in which the piston 9 in rising bears, thus tending to keep
the connecting rod and bearing strap down against the eccentric l. On Fig. A
part of the valve piston g is indicated, as broken away in order to shew clearly the
oblong shaped exhaust port o, oblong explosive mixture admission port p and round
ignition port which are formed in each valve case and its liner respectively at the
positions indicated; the exhaust port o being preferably grated to allow of packing
rings sliding thereover.
The exhaust port o leads to an exhaust pipe (not shewn) the admission port p to
an ordinary gas and air mixing chest r; which has an ordinary gas-inlet valve s
affixed thereto, and the ignition port to an incandescent or hot tube inside an
ordinary Bunsen burner case t indicated at Fig. B.
The gas inlet valves are arranged so that their spindles u shall be on opposite
sides of a projecting stud v fixed on engine frame.
On said stud is fulcrumed at
its centre a lever w which is connected to and oscillated by the rod w' worked by
the eccentric w' on valve shaft. On each end of said lever is fitted a gas engine
pawl or kicker ' which fits against the end of its respective gas valve spindle
which it actuates in usual way, the said valves being thereby opened and shut
alternately.
Referring to the eccentric / Fig. A, revolving as shewn by arrow and as divided
into four parts representing the travel thereof during each engine stroke and
following out the motion thereof and the pistons g over the ports o, p, q, it will be
seen that while the arc a, b, of the eccentric is moving past the point on centre
line of rod; the motor pistons 19, 20 are respectively on the impulse and pumping
outstrokes while the arc b, c, is passing point x, said pistons are respectively on
the exhaust and compression instroke: while arc c, d, is passing point said
pistons 19, 20 are respectively on the inhaling and impulse outstroke: and while
arc d, a, is passing point the said pistons 19, 20 are respectively on the
compressing and exhaust instroke.
:
The eccentric w² is set so as to open the gas supply valves alternately while
b and c, d, of eccentric are passing the point x.
arcs a,
The engine operates as follows;-The cycle of each motor cylinder is the
ordinary 4 stroke, i.e., that of Beau de Rochas or Otto. Assuming the motor
pistons to be in full stroke as shewn at Fig. A, and the space at end of cylinder 1
and between valve pistons g, h, charged with compressed explosive mixture and the
eccentric revolving as indicated by arrow, the top valve g is thus raised until it
uncovers the ignition port a thus allowing said compressed charge to be ignited,
the piston 19 being thereby driven out to end of its stroke, by which time the
valve g shall have been raised sufficiently to uncover exhaust port o, through which
the products of combustion are now driven during the return stroke of piston 19;
the mixing chests having each a non-return valve. When the piston 19 has again

page_text: fully returned, the piston g will have just covered the exhaust port o, the admission
port p being still open through which the explosive mixture is now inhaled during
the next outstroke of piston 19; the pawl u' meanwhile having just been raised
by the eccentric wo and opened the gas supply valve s.
During the next instroke of motor piston 19 (the piston 9 having meanwhile
covered and shut both admission and ignition ports p, q,) the said explosive charge
is compressed until the motor piston 19 is full in, by which time the ignition port q
shall just have been uncovered, thus allowing the charge to be ignited when the
same cycle of operations begins again as just herein described.
The motor piston 20 operates in the same manner, only while the motor piston 19
is on the impulse outstroke, the piston 20 is on the explosive mixture inhaling
outstroke. The connecting rod 4 thus conveys an impulse every revolution to the
crank and shaft 5; and is always in thrust on the outstroke by virtue of one or the
other of the motor pistons 19 and 20 being on the charge compressing instroke,
thus allowing the engine to run at a high-speed without undue back lash or knocking
of working parts.
Figures and D respectively represent a sectional elevation and vertical section
at right angles to one another of the lower cylinder 2 and frame 6 of engine with
starting apparatus arranged according to this invention. The apparatus comprises
a compressed air reservoir (not shown) which communicates by pipe 3' with the
motor cylinder 2 by a port-4' having a stop valve 01 operated by ordinary hand-
wheel 5 on screw spindle. A. valve case 7 fixed to side of engine has a valve 81
therein, which is normally kept shut by the compressed air or spring 9. Said
valve is fixed on top of rod 1 and raised by one end of rocking lever 21 fulcrumed
on stud 31. The other end of lever 21 has projecting therefrom a pin 4" on which
is a roller 511 which is made capable of being slid to or from opposite cam 6¹ so as
to be in or out of gear therewith as desired.
Said cam is made double acting and fitted on end of valve shaft m so that the
valve 8 may be opened at beginning of outstroke of piston 20, otherwise in
lieu of said double cam a single acting cam fixed on crank shaft 5 may obviously
be used to give the same action; the case 7' and spindle 111 being placed to suit
same.
In order to provide an escape for the air every alternate instroke of piston 20,
the piston valve case 15 has formed therein a supplementary exhaust port n'
indicated by dotted circle behind piston.
Said port n' has a stop-cock (not shewn) similarly as port 4' to put it out of
action when desired.
The starting apparatus operates as follows:-While the engine is working and
before being stopped, the roller 5" being out of gear with cam 6' and the exhaust
port n' closed, the port 4' is opened by operating hand-wheel 5¹ and the gas supply cut
off from the cylinder 2, air thus being pumped and compressed into the reservoir until
charged, and retained therein by the valve 81. Otherwise the gas may be allowed to
work in said cylinder and the products of combustion be pumped into and charge the
reservoir. The engine is, or may then be stopped. When starting engine by means
of aforesaid compressed air or products of combustion, the roller 5" is put in gear
with cam 6¹ and supplementary port n¹ opened. The crank shaft is then turned in
usual manner until the cam 6' opens the valve 8' which admits the compressed fluid
to enter above motor piston 20 and drive it full stroke outwards. The momentum
of fly wheel on crank shaft returns said piston and the valve 81 being meanwhile
closed, the air exhausts by either the ordinary or supplementary exhaust ports o or n¹
according to position of valve pistons g, h. By the time the motor piston is again
full in said exhaust ports are closed and valve 8' opened thus allowing the com-
pressed fluid to operate the motor piston again as aforesaid. When the fly wheel
has attained sufficient momentum to bring the cycle of operations of other cylinder 1
(which is meanwhile supplied with gas) into action, the motor fluid alone will
operate the engine. The gas supply valve to cylinder 2 is then opened and the
roller 5 put out of gear with cams 6" and valves n'o' shut. The pistons 19 and 20

page_text: are now alternately actuated by the motor fluid as herein-before described, with
reference to Figs. A and B.
Fig. E, illustrates a mode of providing, in accordance with the invention, a stop
cock to enable the hot or igniting tube 9 of engine being renewed while engine is
working. A hollow case, d" is fixed with the orifice e¹ over or open to the ignition
port of engine valve case and has another orifice f" over and open to which is
fitted the hot tube g which is kept incandescent in the ordinary way. The case d
is fitted with a pin valve h" which is ground on both faces so as when full
outwards, to prevent escape past screw ; and when screwed full inwards to bear
against ground face m and thereby close communication between port n" and
inside of hot tube g" which said tube may then be withdrawn and replaced by a
new tube which when again fixed in place, the pin is screwed out by screw and
hand wheel to position shewn, thus again opening the passage.
To provide for the efficient lubrication of the motor pistons of the engines,
according to this invention, we utilize part of the pressure generated by the motor
fluid behind the motor piston every impulse outstroke to act on the lubricant and
drive part thereof to the desired point to be lubricated.. Apparatus constructed
according thereto is illustrated at Fig. I and consists of an oil cup or vessel "—
closed by a screwed cap s". Said cup is fixed at top by a tube 2 which communi-
cates with the inside of cylinder 1, preferably at a point just behind motor piston 19,
when full out. From the bottom of cup a pipe u leads to a point of cylinder
just opposite a groove round piston when full out; so that at end of impulse
outstroke of motor piston, part of the motor fluid pressure passes through the pipe
and pressing on top of oil in cup drives part thereof through the pipe into
the piston groove . The oil is carried up with piston and lubricates the inside
of cylinder. The pipes t, u, have each a stop-cock for stopping passage
therethrough as desired.
We do not limit ourselves to the particular arrangement or position of ports in
liners 14, 15 as shewu at Fig. A, as such may be varied, as for instance; referring
to diagram G of liner 14 wherein the cylinder port is indicated at ; the ignition
port q, and the inlet port p, may be about located as therein shewn, and respectively
be controlled by the pistons g and ; or said ports may be transposed, and the
exhaust port o in liner dispensed with, and an exhaust port communicating with
inside of cylinder and controlled by a separate valve in usual manner provided, the
non-return valve in mixing chest being dispensed with by virtue of the inlet
port p being placed so as to be uncovered, only during the inhaling stroke of motor
piston.
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 we
claim is
1. The arrangement, construction and combination of gas engines substantially as
herein-before described.
2. In a gas engine having a cylinder fitted with a reciprocating piston and
connecting rod giving an impulse every two revolutions of crank shaft in usual
manner ; the combination therewith of a motor-cylinder mounted concentric or
tandem to first cylinder, and open at one end to the atmosphere, and having a piston
giving an impulse alternately with first piston, thus both pistons combined giving an
impulse, every revolution, to crank shaft substantially as and for the purpose
bereinbefore described.
3. The use of expanding packing rings or equivalents thereof, on the piston
rods of gas engines, or on a stuffing piston on such rods reciprocating in bored
liners or tubes 21 formed or fixed in cylinder end or cover 16 for the purpose
specified.
4. The use in gas motor engines of a balanced valve consisting of two pistons g, h,
fixed on same rod in a casing having ports all arranged and operating substantially
as, and for the purposes specified with reference to Figs. A. and G.

page_text: 5. The use of an air cushioning chamber on top of valve casing 14 as and for the
purpose set forth.
6. In gas engines, actuating two gas inlet valves alternately by means of valve
shaft, revolved by and at half the speed of motor crank shaft m; an eccentric w³,
connecting rod ', oscillating lever w, and valve rods u all arranged, or combined
and operating as specified with reference to Fig. B.
7. The use of a supplementary exhaust valve or port, as and for the purpose set
forth.
8. In combination with the supplementary exhaust port, starting apparatus or
means all arranged and operating as herein before described.
9. The use in gas engines, of a stop-valve, or equivalent thereof, between the
inside of igniting tube and motor cylinder for the purposes specified.
10. The general arrangement, construction, and combination of parts, con-
stituting the lubricator, substantially as hereinbefore described, or any mere
modification thereof.
11. Utilising part of the pressure generated in gas engine cylinders to force
the lubricant to, or on part desired to be lubricated, substantially as set forth.
Dated this 19th day of October 1893.
D. F. MASON, C.E.,
Glasgow, Patent Agent.