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Патент USA US2113936

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April '12, 1938.
Filed July 21, 1934
4 Sheets-Sheet l
‘April 12, 1938.
Filed July 21, 1954
4 Sheets-Sheet 4
P7 z
5.3 ‘
Patented Apr. 12, 1938
UNITED lgsra'rss rarest caries
‘L. Fickett, William 0. Forman, and Philip
E. Arthur, Fitchburg, MassL, assignors toFitch
burg Engineering Corporation, Fitchburg,
Mass, a corporation of Massachusetts
Application July 21, 1934, Serial No. 736,388
(Cl. 121-149)
3 Claims.
tion It which is‘ the suction tank for the oil 7
pump, as will appear.
The principal objects of this invention are to
provide a simple and compact ‘steam: engine that
willoperate at high speed; to provide hydraulic
means for operating thevalves; to provide a hy
The entire framework is enclosed and all the
' mechanism is enclosed in it.
draulic push rod without clearance’ and of the
proper length‘ at all times; to provide'a lubricat
“ng system which will keep the ‘so-called push
rod ?lled with 'oil at all times; to provide a con
struction ‘in which the cylinder is provided with
an- angular ‘exhaust port and the piston head is
of a generalconical shape having the same angle
as the exhaust port for insuring a thorough
sweeping of the piston head at each exhaust; ‘to
provide the cylinder block in‘such a form that
a steam jacket and inlet manifold are formed
therein when the cylinder sleeves are pressed in;
to provide it With‘a shelf at‘ the lower end forming
' 2
Above the base Ill
is located an upper casting it which is bored. out
at IE to provide for the several engine cylinders
H. In bearings, located between the two sections
Ill and i5, is the crank shaft [4 having a fly wheel
It or the like.
It will be seen that a straight hole can be no
bored vertically in the form shown, into this cas
ing i5 and that the casting is so formed that,
when these holes are bored and the cylinder
sleeves ll pressed in, the steam jacket and the
inlet manifold 20 are formed. There is a second
shelf ill at the lower end which bounds a com
mon exhaust belt 22 for the several cylinders,
communicating with the exhaust ports 23 which
a common exhaust belt with the exhaust port. are drilled through the cylinders proper. These
of a plurality of cylinders, and to provide an im
ports are drilled at a ‘distance down on the stroke
proved governor for controlling the hydraulically so that they are uncovered at practically nine "20
operated valves.
tenths of the stroke downward and remain un
Other‘ objects and advantages of theinvention covered for the rest of the stroke. These ports
will appear hereinafter.
are made at an angle and the angle ismade de?
Reference is to be'had to the accompanying nitely'to match the’ angle of the dome shaped
drawings, in which
piston head 24. The ports are of sumcient length
Fig. 1 is a side elevation of a three cylinder uni
so that at the extreme end of the stroke the ex
?ow steam engine constructed in accordance with haust port extends a little below the piston head.
this invention, showingone end of it as a central This projection is made to insure'a thorough
sectional vertical view through the axis of the I sweeping of the piston head at each exhaust'and so
crank shaft;
provide adequate drainageiso that no water can
' Fig.‘ 2 is a sectional ‘view of one of the cylin
be trapped and carried back up with the piston.
,ders on the line 2-2 of Fig. 1;
As has been stated, individual cylinder heads
Fig. 3 is an enlarged sectional View of the. upper 25 are provided; having a conical shape so that
end- of one of vthe cylinder heads;
the: piston can go very close to the head, on its as
Fig. 4 is an elevation of the same features;
Fig. 5 is a section of the‘cylinder head on the
line 5-—5 of Fig. 3;
Fig.6 is a central longitudinal sectional view
of the governor and associated parts, and
Fig. 7 is an end view of the same with parts
in section on the line '|-—'l of Fig. 6.
The engine is, shown as being mounted‘on and
contained in a hollow‘casting H) which constitutes
the base, frame, and easing of the machine. This
45 constitutes a tank for oil and is provided with
a compartment H extending lower than the rest
of it and havinga drain l2 into it for the water
collected at the bottom of the oil tank. At the
oppositeend it is provided With another depressed
receptacle l3 and the wall which connects it with
the‘ tank proper is provided with an over?ow
opening l8 which keeps the oil in the tank at such
a level that the cranks will just avoid thelevel
of the oiliin' operation. The oil runs from the
surface'of the oil pool in the tank into the sec
upward stroke, thus reducing the volumetric
clearance. On the casting l5 lugs 26 are provided
into which studs are screwed to secure the cylin
der heads thereto. These lugs are not made ‘con
tinuous butare spaced apart inside so that a 40
steam passage is’ left between each two successive
lugs to allow, the steam to ?ow-upward and ?ll
the space in the cylinder head above the top of’
the cylinder.
The cylinder is’ open centrally at the top pro
viding a steam inlet port 21. A single beat pop
pet valve 28 is seated in the exact centerof each
cylinder and, instead of being actuated by rocker
arms or other mechanical devices, it ‘is operated
by a piston 29 rigidly fastened to the end of the 50
valve stem 30. This piston is free to move up and
down in a cylinder 3|, which constitutes the
upper end of the engine.
The piston rod, or
valve stem, is prov1ded with a ?brous packing
'40 to prevent oil leaking down the valve stem 55
from the operating piston. Steam is prevented
from leaking up the valve stem from the steam
chest by a series of grooves 4| in the nature of
a labyrinth packing. An annular chamber 42 is
formed in the valve stem guide below the ?brous
packing. This is connected by a pipe 43 to the
exhaust system of the engine to allow any water
that works up the valve stem to be removed
of the spring 66, the compression of which is de
termined by the adjustable cap 61.
constantly from this point. Above the piston 29
10 a drain 44 is provided to take any oil that leaks
As the engine speeds up, the governor weights ll)
by the piston back through this pipe to the crank
on the bell cranks 64 are thrown outwardly by
The cylinder below the piston 29 and the pipe
connected to it are kept constantly ?lled with oil
15 through a pipe 45 having a conventional check
valve 45, see Fig. 4. This oil in the system is
maintained by being connected to the pressure
lubricating system of the engine. This pressure
is available at all times when the engine is run
ning by means of a pump 41 shown as a gear
pump mounted on the front- bearing cap and
driven by means of gears 48 and 49. As will
appear, the gear 48 is connected with the crank
shaft. This pump draws oil from the depressed
portion l3 and at the front of the crank case
through a pipe 56.
The main bearings are lubricated by pipes 5|
receiving oil at a predetermined pressure from
the pump 47. The magnitude of this pressure is
30 determined by a spring loaded relief valve 52 con
nected into the system. A drilled hole 53 from
the center of the main journal to the center of
the crank pin conveys oil under pressure to the
The pistons 24 are of the trunk type and serve
the dual capacity of piston'and cross head. The
piston pin or wrist pin 55 is hollow and, to pre
vent steam passing into the wrist pin, the ends
are counterbored, and after the pin is in place
a Welch plug seals both ends. Each cylinder is
provided at the bottom with an annular ring 56
which is provided with a low bottom or sump to
collect any condensate that ?ows from the cyl
inder walls and a pipe 57 is used to drain it off
to any desired point, as for example, the separat
45 ing chamber H.
For the purpose of controlling the stroke of the
plunger so that it will be proportionate to the load
of the engine and for other well known purposes,
50 a governor is provided. The gear 48 is pinned
to the end of the crank shaft I4 and a splined
shaft 58 to which the gear 48 is ?xed is thereby
?xed to the crank shaft. In this way the gear
48 serves the double purpose of driving the pump
55 4'! and furnishing a non-slip drive for the shaft
58 which is the governor shaft. The two pins are
driven into the crank shaft after the engine is
properly set. No angular movement of these
shafts can occur thereafter.
A'governor frame 60 is provided which con
stitutes a hollow casing for receiving the entire
This governor is provided with a se
ries of radial cylinders 6! in which are located
plungers 62, each one preferably having a spring
gular position on the cam and the recession is
a constant variable along a spiral path. Thus,
while the valves are always open at the same po
sition on the stroke, the cut-01f is governed by
the time of their closure. The cam is shown in
Figs. 6 and 7 in a position to give maximum valve a
opening and it is held in this position by means
centrifugal force. This causes a reaction on the
frame 65 and against a hardened wear member
10 inserted in the end of the shaft 58 at the
point of impingement. It is obvious that an out
ward movement of the governor weights will cause
the governor carrier and cam to slide along the
shaft in a direction to compress the spring 66.
This, of course, moves the cam under one of the
several rollers 69 to a point of lower rise and 20
shorter opening on the cam.
In case of what would be called a runaway
speed, the weights move out ‘a sufficient distance
so that the concentric portion of the cam will be
under the roller and no plunger movement would 25
result. Of course, a number of valve operating
cylinders BI is provided to correspond with the
cylinders and they are equally spaced circum
ferentially. Thus a single lobed cam will operate
properly a chosen number of cylinders. The 30
spring behind the valve operating cylinders is
used for extremely high speeds and it is employed
to insure the plunger 62 followingthe cam. -
,Each of the plungers 62 acts to apply pressure
through a pipe H to the plunger 29 and operate
the valve 28. It will be understood that the
pump 47 keeps an otherwise constant pressure
on this plunger and that this additional pressure
of the individual plungers 6? causes the opera
tion of the valve. .11; will be observed that the
oil in each one of the pipes ‘H is under pressure
at all times and this oil serves as a liquid push
rod which, of course, will'be at proper length
at all times and it operates entirely without
In following the operation of a single cylinder,
let it be assumed that this cylinder is 'full of oil
as is also the pipe ‘H and the portion of the
cylinder below the piston. Let it be also assumed
that the roll 59 for that cylinder is raised on a ,.
base circle of the cam. There is an initial or
static pressure in this oiling system equal to the
pressure of the lubricating system. The cam 68
now revolves until it lifts the plunger in ques
tion. The oil is prevented from flowing back to
the lubricating system under the in?uence of a
higher pressure by the check valve 46. Conse
quently, any further movement of the plunger
62 must lift the piston 29 and admit steam to
that cylinder. The action of the steam coming in
through the inlet 20 and ?lling the space above
the conical dome of the cylinder pushes down the
working piston in the cylinder and the regular
functions of the steam engine are carried on
63 behind it. Pivotally mounted on a stationary
as will be obvious. When the plunger
part' are bell cranks 64 having the governor
62 again reaches the concentric portion of the
weights located upon them. Their inner ends are cam, if there has been any leakage in the oil
located in the yoke 65 movable in an axial direc
system, this will be immediately ‘replenished
tion, the movement being resisted by a spring 55 through the'check valve 46 because the pressure
which is held in a cap 61 adjustable. in the frame outside the system is higher than that inside.
to adjust the governor. Movable with this sliding '
The engine is constructed so that the piston 29 To
frame 65 is a cam F58. Rollers 69, one to each is packed by means of a ?brous packing 48 so
engine cylinder and one to each plunger 62, that very little leakage occurs at this point. The
bear on this cam. The cam is of the variable
lift type. The lift commencesat a constant an- r
plunger 62, however, has merely a sliding ?t in
the ring and there is some leakage at this point.
This is premeditated and provided for because
this leakage at the bottom, or cool end, of the
valve lifting system serves to oil the plunger and
its roller and pin. It also allows a little fresh
oil to be taken in at the upper end of the system
on each stroke. In this way, eventually all the
oil in the valve operating system will be changed.
Thus the retention of oil in the upper end of the
, system which is comparatively hot, is prevented.
10 If any oil were retained there it would be apt to
be broken down or carbonized by the action of
the heat.
Of course, there is no pressure on the valve
operating replenishing means when the engine is
15 at rest. Consequently the engine is provided
with a small hand operated pump‘ 15 which,
through a pipe 16, can build up pressure in this
system before the engine is started.
comparatively simple and when manufactured it
is particularly suitable for high speeds.
Although we have illustrated and described
only one form of the invention we are aware of
the fact that modi?cations can be made therein
by any person skilled in the art without depart
ing from the scope of the invention as expressed
in the claims.
Therefore, we do not wish to be
limited in this respect otherwise than as set forth
in the claims, but What we do claim is:——
1. In a steam engine, the combination of a
‘main engine cylinder, crank shaft, and piston,
the cylinder having a port for the admission of
steam, a valve for controlling said port, a cyl
inder and piston connected with the valve, a 15
crank shaft operated directly by the engine pis
ton, a pump connected with the engine crank
shaft to be operated thereby, a check valve con- ,
The engine is arranged so that the overflowv 'nected with the pump for keeping a predeter
from the engine lubricating system and‘ from the mined pressure of oil on the last named cylinder, 20
20 spring pressure release valve is discharged into and means operated by the. crank shaft for peri
the governor case, thus effectively lubricating the odically increasing the pressure under the sec
' ondlpiston to open‘ the valve, said means com
governor and all its associated apparatus.
prising a column of liquid which acts as a push
This engine is designed for high speed opera
rod operating without clearance.
2. In a steam. engine, the combination of a
.usually operative in reciprocating steam engines.
It will be seen ‘that this engine is provided with
hydraulic means for operating the steam engine
valves and with a hydraulic “push rod” which
will remain in the proper length at all times and
operates without clearance. ‘The advantages of
these features are believed to be obvious and will
not be further elaborated.
The so-called second shelf which forms, and
35 has spaced above it, a common exhaust belt com
, municating with the exhaust ports of all the cyl
inders also is a feature of importance. The in
take provides a body of live steam around the
tops of the several cylinders at all times and the
40 exhaust steam also constitutes a jacket around
them at a lower level.
By means of the combination the angularly,
disposed ports‘in the cylinders and the conical
top surface of the piston, not only is the flow of
vsteam outwardly interrupted but by arranging
the pistons so that the port is always a little
belowthe piston head at the lower point in the
stroke, the piston head is thoroughly swept at
each exhaust and adequate drainage is provided
to prevent the trapping and carrying back of
water with the piston. The lubricating system
main steam cylinder having a steam admission,
valve, a piston on the stem thereof, a second
cylinder in which the piston is located, a main
piston in the ?rst named cylinder, a crank shaft 30
pivoted to and operated by the main piston, a
pumpv operated by the crank shaft and arranged
to supply oil to the second cylinder to normally
keep the pressure on the ?rst. named piston but
not enough to open the valve, means including 35
a pressure relief valve for regulating the pressure
and keeping it constant, and a column of liquid
connected with the cylinder and operated by the
crank shaft for increasing the pressure in the
?rst named cylinder periodically and opening the 40
steam admission valve.
3. In a steam engine, the combination of a
crank shaft, a plurality of pistons connected
therewith, a main engine piston and cylinder, an
inlet valve for one of the ?rst named pistons and 45
cylinders operated by the second piston and cyl
inder, means including a pressure relief valve for
maintaining a predetermined pressure on the
second; piston when the engine is operating, a
cam rotatable with the crank shaft, a series of 50
plungers, one for each main cylinder connected
to be operated by said cam, and a column of oil
by which the oil is all changed so that the same ' between each plunger and the piston connected
oil cannot be left in the hot end of the oil sys-i for operating the correspondingvalve, whereby
item prevents the carbonization of the oil by the as the cam rotates it will operate the plungers
heat. The whole design is of such a nature as in the proper sequence to apply pressure to the
to protect the operating parts from becoming
cooled by outside air and acquiring a deposit of
dirt or dust‘and also provides a compact con
60 struction. The manufacture ‘of the engine is
oil in said column and actuate the valves.
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