Internal combustion engine for vehicles

An internal combustion engine (20) which includes an oscillating piston (52) and rotary valves (34) and (36) is shown. Oscillating movement of piston shaft (50) is transmitted to oscillating idler shaft (66). Outer and inner coaxial shafts (82) and (84) are connected by direction reversing gears (88) for counterrotation of the shafts. Outer shaft (82) is connected to oscillating shaft 66 through gear sets (102) and (104), and inner shaft (84) is connected thereto through gear sets (106) and (108). Gear sets (102) and (106) include one-way overrunning clutches (110) and (112), and gear sets (104) and (108) include electromagnetically controlled friction clutches. (See FIG. 1) In FIG. 13, mechanically operated clutches (200A) and (200B) are used in place of the electromagnetically controlled friction clutches shown in FIG. 1, and in FIG. 17, sector gear sets (244) and (246) connect oscillating shaft 66 to respective coaxial shafts (82) and (84). Threaded arms (300A and 300B), extend radially outwardly from oscillating shaft (50) and motors (302A and 302B) are movable along the arms for control of the moment of inertia of the oscillating shaft (50).

FIELD OF THE INVENTION 
This invention relates generally to an internal combustion engine having an 
oscillating shaft and to means for converting oscillating motion of the 
shaft to rotary motion. 
BACKGROUND OF THE INVENTION 
Oscillating piston internal combustion engines are well known as shown, for 
example, in U.S. Pat. No. 1,189,834--Kress, U.S. Pat. No. 
1,468,516--Schiller, U.S. Pat. No. 1,705,826--Polizzi, and British Patent 
Number 577,656--Johnson. 
Many prior art internal combustion engines include a crank mechanism for 
connection of the engine piston to the engine output shaft. The effective 
length of the crank arm varies in a manner dependent upon the angular 
position thereof, thereby limiting engine operating efficiency. 
SUMMARY AND OBJECTS OF THE INVENTION 
An object of this invention is the provision of an improved internal 
combustion engine which is capable of high torque output. 
An object of this invention is the provision of improved connecting means 
for connection of the oscillating shaft of an internal combustion engine 
to an engine output shaft. 
An object of this invention is the provision of an improved internal 
combustion engine of the above-mentioned type which is well adapted for 
use in a motor vehicle. 
An object of this invention is the provision of an oscillating piston 
engine which includes a pair of pistons which are connected for 
oscillation in opposite directions for improved engine balance. 
The above and other objects of this invention are achieved by use of an 
internal combustion engine which includes movable piston means connected 
to an oscillating shaft. Torque on the shaft is directly dependent upon 
the degree of force by which the pistons are propelled upon combustion and 
is substantially independent of piston location along path of travel. 
Consequently, large torque may be applied to the oscillating shaft at 
combustion when the piston is at one end of travel. 
The engine of this invention includes first and second counterrotating 
coaxial shafts rotatable in first and second opposite directions, 
respectively. The oscillating engine shaft is alternately connected to the 
first and second coaxial shafts for drive rotation of the first shaft in 
said first direction upon oscillation of the oscillating shaft in one 
direction, and for drive rotation of the second shaft in said second 
direction upon oscillation of the oscillating shaft in the opposite 
direction. The first and second coaxial shafts are interconnected for 
simultaneous counterrotation thereof upon rotation of either shaft by said 
oscillating shaft. In one embodiment which is particularly adapted for 
motor vehicle use, the connection of the oscillating shaft to the first 
coaxial shaft includes a first overrunning one-way clutch and a first 
actuatable friction clutch in shunt. Similarly, the connection of the 
oscillating shaft to the second coaxial shaft includes a second 
overrunning one-way clutch and second actuatable friction clutch in shunt. 
Either mechanical or electromagnetic clutch actuating means are provided 
for control of the actuatable clutches. The one-way clutches function to 
connect the oscillating shaft to the coaxial shafts during drive actuation 
of the counterrotating shafts by the oscillating piston engine. During 
vehicle coasting, the overrunning clutches operate in the overrunning mode 
whereby no braking by the engine is provided. Such free-wheeling clutch 
operation contributes to vehicle operating efficiency. During engine 
starting and vehicle braking operations, the actuatable clutches are 
enabled for drive actuation of the oscillating piston engine by rotation 
of the first and second counterrotating coaxial shafts. 
In another embodiment, oscillating movement of the engine shaft is 
converted to rotary motion of the counterrotating coaxial shafts by first 
and second sector gears driven with an oscillatory motion by the 
oscillating piston shaft. Third and fourth sector gears are affixed to the 
first and second coaxial shafts, respectively, such that during engine 
operation the first and third sector gears and second and fourth sector 
gears are alternately engaged and disengaged. The first and third sector 
gears and second and fourth sector gears are simultaneously disengaged 
adjacent opposite ends of oscillating movement of the oscillating engine 
shaft, during which times detent means limit rotary movement of the 
oscillating shaft to assure reengagement of the sector gears. 
In one embodiment of this invention the combustion engine includes use of a 
combustion unit comprising a cylinder housing formed with a partially 
cylindrical working chamber closed at opposite ends by plane end walls. A 
piston shaft rotatably supported by the end walls extends through the 
chamber coaxially with the partially cylindrical working chamber. A piston 
is affixed to the piston shaft and extends radially therefrom, which 
piston divides the working chamber into first and second sub-chambers. 
Each sub-chamber is provided with inlet and exhaust port means for the 
supply of air to the sub-chambers and exhaust of gases therefrom. Valve 
means, such as first and second rotary valves having separate intake and 
exhaust passages formed therein, control the flow of fluid into and out of 
the sub-chambers. The rotary valves are intermittently rotated ninety 
degrees in timed relationship with the piston oscillation, such that the 
operating cycle of each sub-chamber includes successive intake, 
compression, expansion and exhaust phases. 
To compensate for unbalanced piston motion, the engine may include a pair 
of working chambers and associated oscillating pistons, together with 
means for interconnecting the piston shafts through direction-reversing 
means such that when one piston swings in one rotary direction, the other 
piston swings in the opposite rotary direction. With this arrangement, the 
operating cycles of the four sub-chambers may be arranged to provide an 
expansion phase with each swing of the piston. 
In another embodiment of this invention, the engine includes reciprocating 
pistons which are coupled to a shaft for driving the shaft with an 
oscillating motion. Means, such as described above, are used to convert 
the oscillating shaft motion to rotary motion.

DESCRIPTION OF PREFERRED EMBODIMENTS 
Reference first is made to FIGS. 1A, 1B and 2 wherein the novel internal 
combustion engine 20 of this invention is shown to include a combustion 
unit 22 comprising a stationary piston housing 24 formed with a partially 
cylindrical working chamber 26 having a longitudinal axis 28. Working 
chamber 26 extends between opposite end walls 30 and 32 which are attached 
to housing 24 by any suitable means not shown. In practice, housing 24 is 
formed with separate block and removable head sections to provide ready 
access to rotary valves 34 and 36. It here will be noted that although 
rotary valves are illustrated, conventional poppet valves may be employed 
in place thereof, the invention not being limited to the use of rotary 
valves. Valves 34 and 36 are journaled to end walls 30 and 32 by bearings, 
not shown, for rotary motion about axes that extend parallel to axis 28. 
Seal means 38 (see FIG. 2) in grooves in housing 24 provide for sealing 
engagement between the valves and housing. Each valve is provided with an 
inlet passage 40 and outlet passage 42 adapted for communication with 
inlet ports 44 and exhaust ports 46, respectively, in the engine housing. 
Transverse dividing walls 48,48 in housing 24 separate the inlet and 
exhaust ports. An air/fuel mixture from a source not shown, such as a 
carburetor, is supplied to the engine through inlet ports 44. 
A piston shaft 50 is journaled to end walls 30 and 32 by bearings, not 
shown, for oscillating pivotal movement about axis 28. A single piston, or 
vane, 52 is affixed to shaft 50 for rotation therewith about axis 28. 
Piston 52 is formed with a hub 54 through which piston shaft 50 extends 
for attachment of the piston to the shaft. Seal means 56 provide sealing 
engagement between the piston and working chamber. 
The piston 52 divides working chamber 26 into two sub-chambers 26A and 26B, 
one of which increases in volume while the other decreases during 
oscillation of piston 52 therein. Both sub-chambers 26A and 26B are 
provided with ignition devices 58, such as spark plugs, for ignition of 
compressed air/fuel mixtures in the sub-chambers and oscillation of piston 
52 in the working chamber. 
A drive train housing 60 is attached to one end of combustion unit 22 at 
end wall 32 by means not shown. It includes an outer wall 62 and end wall 
64. Piston shaft 50 also is journaled to end wall 64 by bearing means not 
shown. An idler shaft 66 extends through housing 60 and is journaled to 
end walls 32 and 64 by bearings, not shown, for rotation about axis 68 
parallel to piston axis 28. Sector gear 70 attached to piston shaft 50 and 
cooperating gear 72 attached to idler shaft 66 transmit oscillatory motion 
of the piston shaft to the idler shaft. By selection of the gear ratio 
between gears 70 and 72, the idler shaft may be provided with the desired 
degree of oscillatory rotation. If desired, non-circular gears may be 
employed. Also, as will be apparent, if the oscillatory piston shaft 50 
undergoes the desired angular rotational movement, there would be no need 
for idler shaft 66 and associated gears 70 and 72 connecting the same to 
piston shaft 50. 
Oscillatory travel of piston 52 is limited by stop means 74,74 affixed to 
end wall 32, which stop means are engaged by sector gear 70 at opposite 
ends of travel thereof. In FIG. 4, the stop means 74 is shown to include 
an arm 76 extending from end wall 32 to which spring 78 is affixed. An 
abutment pad 80 is attached to the outer end of spring 78, and is adapted 
for engagement with the edge of sector gear 70 to limit rotation thereof. 
The spring cushions the impact and facilitates reversal of the piston 
movement. 
The engine includes first and second coaxial shafts 82 and 84, the outer 
one 82 of which is journaled to end wall 32, and the inner one 84 of which 
is journaled to end walls 30 and 64. The axis 86 of the coaxial shafts 82 
and 84 extends parallel to axis 68 of idler shaft 66 and axis 28 of piston 
shaft 50. Means 88 are provided for interconnecting said coaxial shafts 82 
and 84 for simultaneous counterrotation thereof upon rotation of either 
one thereof. For purposes of illustration, means 88 are shown to include 
first and second bevel gears 90 and 92 affixed to outer and inner shafts 
82 and 84, respectively, and idler gear 94 between said first and second 
bevel gears, which idler gear is adapted for rotation about axis 96 normal 
to axis 86. In the illustrated arrangement, outer shaft 82 is adapted for 
rotation in the direction of arrow 98 while inner shaft 84 is adapted for 
counterrotation, in the direction of arrow 100, as seen in FIG. 1A. 
Idler shaft 66 is adapted for connection to outer shaft 82 through first 
gear set 102 which includes spur gears 102A and 102B, and second gear set 
104 which includes spur gears 104A and 104B. Similarly, idler shaft 66 is 
adapted for connection to inner shaft 84 through first gear set 106 which 
includes spur gears 106A and 106B, and second gear set 108 which includes 
spur gears 108A and 108B. Gears 102A and 106A of gear sets 102 and 106 
include, or incorporate, one way clutches 110 and 112, respectively, 
whereby gear 102A is adapted to be driven in a clockwise direction(in the 
direction of arrow 114 as seen in FIG. 1B) upon rotation of idler shaft 66 
in that direction, and gear 106A is adapted to be driven in a 
counterclockwise direction (in the direction of arrow 116) upon rotation 
of idler shaft in the counterclockwise direction. Consequently, outer 
shaft 82 is rotated in direction of arrow 98, and inner shaft 84 is 
rotated in the opposite direction, in the direction of arrow 100, when 
driven by operation of the oscillating piston engine. Either shaft 82 or 
84, or both shafts, may be employed as the engine output shaft, and for 
purposes of illustration, shaft 84 is shown connected to a transmission 
117. For vehicular use, the output from the transmission is adapted for 
connection to vehicle wheels for driving the same. 
Gears 104A and 108A are rotatably mounted on idler shaft 66, and are 
included in first and second actuatable clutch means 118 and 120, 
respectively. For purposes of illustration, clutch means 118 and 120 are 
shown comprising electromagnetically controlled friction clutches each of 
which includes a housing 122 attached to oscillating idler shaft 66. 
Electromagnets 123 are carried by the housings which when energized, 
attract spur gears 104A and 108A thereto. Gears 104A and 108A are 
rotatably mounted on idler shaft 66 such that when the electromagnets are 
deenergized, they remain uncoupled to the shaft. The gears are drawn into 
tight frictional engagement with housings 122 when the electromagnets are 
energized for coupling of the gears to the idler shaft. The clutch means 
are shown in greater detail in FIG. 9 described hereinbelow. For present 
purposes, it will be understood that actuatable clutch means 118 and 120 
are alternately energized and deenergized whenever drive actuation of the 
engine by the counterrotating shafts 82 and 84 is desired as, for example, 
during engine starting and vehicle braking. 
Since coaxial shafts 82 and 84 simultaneous rotate in opposite directions, 
either one, or both, may be employed as the engine output shaft. In the 
illustrated embodiments, rotary valves 34 and 36 are intermittently 
rotated by connection thereof to outer coaxial shaft 82 through a belt 124 
and pulley 126. Pulley 126 is fixedly attached to a gear wheel 128 and 
together, are rotatably mounted on piston shaft 50. Gear wheel 128 is 
provided with gear segments 128A at the four quadrants thereof which are 
adapted for intermittent engagement with gear wheels 130 and 132 upon 
rotation of gear wheel 128. Gear wheels 130 and 132 are, in turn, 
connected to valves 34 and 36 through square valve shafts 34A and 36A 
extending from the valve for intermittent rotation of the valves upon 
continuous rotation of gear wheel 128. An enlarged elevational view of 
this mechanism is shown in FIG. 5. 
The opposite ends of square valve shafts 34A and 36A extend outwardly from 
end wall 30, and are engaged by leaf springs 134, one end of which springs 
are affixed to arms 136 extending from end wall 30, as seen in FIGS. 6 and 
7. Springs 134 function to resiliently hold the rotary valves at 
90.degree. rotary positions. They also provide an over-center snap action 
function to the valve rotation following rotation beyond 45.degree., and 
stably locate the valves at the ninety degree positions. With this 
arrangement, the valves need not be positively rotated a full 90 degrees 
by gear teeth 128A to provide for the required 90 degree rotations. 
An engine operating cycle for each sub-chamber is diagrammatically 
illustrated in FIGS. 8A through 8D, to which figures reference now is 
made. As described above, rotary valve 34 is associated with sub-chamber 
26A and rotary valve 36 is associated with sub-chamber 26B. In FIG. 8A, 
during clockwise rotation of piston 52, sub-chamber 26A undergoes an 
exhaust phase through valve 34 while a fuel/air mixture is drawn into 
sub-chamber 26B through valve 36. Next, when the piston swings back with a 
counterclockwise motion, fuel/air mixture is drawn into sub-chamber 26A 
through valve 34, and the fuel/air mixture in sub-chamber 26B is 
compressed. (See FIG. 8B.) Then, when piston 52 again swings in a 
clockwise direction as shown in FIG. 8C, the fuel air mixture in 
sub-chamber 26A is compressed, and the compressed fuel/air mixture in 
sub-chamber 26B is ignited for production of a power, or expansion, phase 
at sub-chamber 26B. Next, when piston 52 again swings in a 
counterclockwise direction as shown in FIG. 8D, the compressed fuel/air 
mixture in sub-chamber 26A is ignited for production of an expansion phase 
at sub-chamber 26A, and exhaust gases are expelled from sub-chamber 26B 
through valve 36. As described above, with each clockwise rotation of 
idler shaft 66, by counterclockwise rotation of piston shaft 50, one-way 
clutch 110 is in driving condition for drive actuation of outer shaft 82 
through gear set 102, during which time one-way clutch 112 operates in the 
overrunning condition. Conversely, during counterclockwise rotation of 
idler shaft 66 through gears 70 and 72, one-way clutch 112 is in driving 
condition for drive actuation of inner shaft 84 through gear set 106, 
during which time one-way clutch 110 operates in the overrunning 
condition. So long as actuatable clutches 118 and 120 remain deenergized, 
they do not affect operation of the drive train. 
Reference now is made to FIG. 9 wherein clutches 110 and 118 associated 
with gear sets 102 and 104 are shown in greater detail. As noted above 
clutches 112 and 120 associated with gear sets 106 and 108 are of the same 
types as clutches 110 and 118, respectively, such that a separate detailed 
showing thereof is not required. Clutch 110 comprises a one-way, or 
overrunning, clutch of any suitable design and, for purposes of 
illustration, may comprise rollers 140 located between spur gear 102A and 
inner member 142 attached to shaft 66. Rollers 140, one of which is seen 
in FIG. 9, cooperate with cam surfaces on member 142 to provide for clutch 
engagement, or clutch override, dependent upon the direction of rotation 
of shaft 66. Spring means, not shown, urge the rollers into engagement 
with members 102A and 142. 
Actuatable clutch 118 is shown to comprise housing 122 affixed to shaft 66 
and containing electromagnets 123, one of which is shown in FIG. 9. 
Electromagnets 123 are connected to slip rings 148,148 which, in turn, are 
connected through brushes 150,150 to a voltage source 152 through ignition 
controlled switch 153, switch 154, and one of shunt-connected switches 156 
or 158. Switch 153 is closed whenever the vehicle is placed in operating 
condition by closure of the ignition switch. Switches 156 and 158 normally 
are in an open condition, and are adapted for closure upon actuation of 
the vehicle brakes by brake lever 160, and by operation of the vehicle 
starter under control of starter control circuit 162, respectively. Switch 
154, on the other hand, is alternately opened and closed under control of 
switching control circuit 164. Timing pulses for control of switch control 
circuit 164 are obtained from a photocell 166, shown in FIGS. 1B and 3, 
responsive to timing lines 168 provided on the edge of sector gear 70. 
Timing pulses are produced in synchronism with oscillation of the engine 
piston. In operation, switch 154 is, essentially, closed during motion of 
the piston in one direction, and is opened during motion in the opposite 
direction such that actuated clutch 118 functions as a one-way clutch. 
Means, not shown, are provided for the generation of a signal responsive 
to the direction of oscillatory motion, for use by control circuit 164. 
Similar control means, including switch 154A which is alternately opened 
and closed under control of circuit 164, are provided for controlling 
operation of actuatable clutch means 120 for connection of shaft 66 to 
inner shaft 84 for intermittent drive rotation of shaft 66 by inner shaft 
84 during starting or braking operations. It here will be noted that 
timing pulses from photocell 166 also may be used for ignition timing 
purposes for controlling firing of spark plugs 58. 
During energization of solenoids 123, spur gear 104A is drawn into tight 
frictional engagement with housing 122 for rotation of shaft 66 through 
gear set 104. In the deenergized condition of solenoids 123 illustrated in 
FIG. 9, gear 104A is axially moved away from housing 144 by spring biasing 
means 168 extending between the housing and gear. Ball bearings 170 reduce 
friction between the spring and gear when the clutch is disengaged, and an 
annular stop member 172 on shaft 66 limits axial movement of gear 104A to 
the left as viewed in FIG. 9. In FIG. 1B, the spring biasing means 168 are 
diagrammatically illustrated as "S" shaped members. 
Reference now is made to the timing diagram of FIG. 10 wherein angular rate 
of rotation of the oscillating piston versus time is shown for operation 
when switch -56 is closed during braking operation and/or switch 158 is 
closed during starting operation. At time T0, switch 154 is closed whereby 
clutch 118 is in the energized condition for engagement thereof, and 
switch 154B is open whereby clutch 120 is in the deenergized condition for 
disengagement thereof. If, at this time, the speed at which shaft 66 is 
being driven by the engine relative to the speed at which outer shaft 82 
is rotated by the starter, or by vehicle movement during braking, is such 
that both overrunning clutches 110 and 112 operate in the overrunning 
condition, then piston shaft 50 is driven in a counterclockwise direction 
by the rotating outer shaft 82. Under these conditions shaft 82 comprises 
the driving shaft, and piston shaft 50 comprises the driven shaft through 
operation of electromagnetic friction clutch 118. During braking, the 
engine thereby assists in the braking function. At time T1, near the end 
of piston travel in the counterclockwise direction, switch 154 opens 
whereby both clutch 118 and clutch 120 are deenergized. Shortly 
thereafter, the piston stops and the direction of oscillation is reversed. 
After changing to a clockwise direction of rotation, clutch 120 is 
energized at time T2 for engagement thereof for drive actuation of the 
piston shaft in the clockwise direction by the rotating inner shaft 84. At 
time T3, clutch 120 is deenergized and, after the direction of oscillation 
again reverses to the counterclockwise direction of rotation, clutch 118 
is energized at time T4. Successive energization and deenergization of 
clutches 118 and 120 continue so long as brake switch 156 or starter 
switch 158 remains closed, and coaxial output shafts 82 and 84 continue to 
rotate. While output shafts 82 and 84 function as driving shafts, and 
piston shaft 50 functions as the driven shaft, both one-way clutches 110 
and 112 continuously operate in the overrunning condition. When piston 
shaft 50 functions as the driving shaft, overrunning clutches 110 and 112 
operate whereby coaxial shafts 82 and 84 alternately function as driven 
and overrunning shafts regardless of operation of the actuatable clutches 
118 and 120. 
Obviously, the engine is not limited to use of a single piston. Reference 
now is made to FIG. 1 wherein a multipiston engine is shown which includes 
first and second pistons 52 and 52-1. Piston shaft 50 to which piston 52 
is affixed is connected to coaxial output shafts 82 and 84 in the manner 
described above. The illustrated engine includes a second housing 24-1 of 
the same design as housing 24, which housings 24 and 24-1 are 
interconnected by a housing 174. Housing 24-1 also is provided with a pair 
of rotary valves of the same type as rotary valves 34 and 36. Valves 34 
and 36 are connected to corresponding rotary valves in housing 24-1 by 
axial extensions of the valve shafts. In FIG. 11, a portion of one such 
extension 36B for connection of valve 36 to the corresponding valve in 
housing 24-1 is shown. 
Piston 52-1 is affixed to piston shaft 50-1 which, in turn, is journaled to 
end walls 30-1 and 32-1. Piston shafts 50 and 50-1, which are axially 
aligned, are adapted for simultaneous pivotal movement about axis 28. They 
are interconnected by reversing means 176 for simultaneous pivotal 
movement in opposite directions. Reversing means 176 may be of the same 
type as means 88 for interconnecting the coaxial output shafts 82 and 84. 
It is shown comprising a first bevel gear 178 attached to one end of 
piston shaft 50, second bevel gear 180 attached to the opposing end of 
shaft 50-1, and an idler gear 182 between gears 178 and 180, which idler 
gear is adapted for rotation about axis 184 normal to axis 28. By 
interconnecting the piston shafts through direction reversing means, one 
shaft is made to rotate in one direction while the other is rotated in the 
opposite direction for reducing engine vibration. 
In operation of the single piston engine illustrated in FIG. 8A through 8D, 
successive expansion, or power, phases are seen to take place in the 
course of one complete back and forth movement of the oscillating piston. 
These power phases are followed by non-power phases during the following 
complete back and forth movement of the piston. With the two-piston engine 
shown in FIG. 11, a power phase is provided every movement of the pistons. 
Simultaneous exhaust, intake, compression and expansion phases take place 
at the four sub-chambers of the two-piston engine every swing of the 
pistons. Consequently, a compression phase in one sub-chamber is 
accompanied by an expansion phase in another sub-chamber to further 
contribute to engine balance. Obviously, the engine may be provided with 
additional oscillating pistons if desired. 
Reference now is made to FIG. 12 wherein a modified form of this invention 
is shown which includes first and second actuatable clutch means 118 and 
120 of the type described above included in the connection of the 
oscillating piston shaft 50 to the counterrotating output shafts 82 and 
84. The embodiment of FIG. 12 differs from the above-described 
arrangements in the elimination of one-way, overrunning, clutches in shunt 
with the actuatable clutches 118 and 120. Clutch actuating circuits of the 
general type illustrated in FIG. 9 may be used, in which one terminal of 
battery 152 is directly connected to switches 154 and 154A rather than 
being connected thereto through switch 156 or switch 158. With this 
arrangement, operation of the clutches is dependent upon closure of 
ignition-controlled switch 153, and not upon actuation of the brakes or 
energization of the starter motor. So long as ignition-controlled switch 
153 is closed, opening and closing of switch 154 controls engagement and 
disengagement of clutch 118. Clutch 120 is controlled in a similar manner 
through switch 154A. Timing of the operation of clutches 118 and 120 is 
the same as that illustrated in FIG. 10 described above. With this novel 
clutch and clutch actuating means, piston shaft 50 may be driven by the 
counterrotating output shafts 82 and 84 any time during engine operation, 
independently of operation of the brakes or operation of the starter. 
Obviously, the invention is not limited to electromagnetic friction 
clutches in the connection of the piston shaft to the counterrotating 
output shafts. In FIGS. 13 and 14, to which reference now is made, 
mechanically operated clutches 200A and 200B are shown for connection of 
an oscillating shaft 202 to counterrotating output shafts 82 and 84, 
respectively. Shaft 202 may correspond to oscillating idler shaft 66, or 
to oscillating piston shaft 50, in the arrangements described above. 
Clutches 200A and 200B include plates 204A and 204B affixed to oscillating 
shaft 202, and plates 206A and 206B in the form of spur gears rotatably 
supported on shaft 202. Clutch actuating means 208A and 208B for 
controlling engagement and disengagement of the clutches include thrust 
bearings 210A and 210B on oscillating shaft 202 which are axially movable 
therealong under control of pivotal clutch actuating levers 212A and 212B, 
respectively. Springs 214A and 214B resiliently bias the levers in a 
clockwise direction, as viewed in FIG. 13, about pivot pins 216A and 216B 
and into engagement with cams 218A and 218B, respectively. In the 
drawings, clutch 200A is shown in the engaged condition, and clutch 200B 
is shown in the released condition. 
Cams 218A and 218B are affixed to idler shafts 220A and 220B, respectively, 
which are intermittently rotated by oscillating shaft 202 through one-way 
clutches 222A and 222B of any suitable design. Clutches 222A and 222B 
include gear wheels which are driven by gears 224A and 224B, respectively, 
attached to oscillating shaft 202. As shown in FIG. 14, oscillating motion 
of shaft 202 is converted by one-way clutch 222A to intermittent rotation 
of cam 218A in a counterclockwise direction, and by one-way clutch 222B to 
intermittent rotation of cam 218B in a clockwise direction. For each 
oscillating movement of shaft 202 in the clockwise direction, cam 218A is 
rotated one complete revolution in the counterclockwise direction. During 
rotation of shaft 202 in the counterclockwise direction, one-way clutch 
222A operates in the overrunning condition whereby cam 218A remains 
stationary. Similarly, cam 218B is rotated one complete revolution upon 
oscillating movement of shaft 202 in a counterclockwise direction through 
clutch 222B, and remains stationary during clockwise rotation of shaft 
202. 
Spur gears 206A and 206B of clutches 200A and 200B are coupled to outer and 
inner shafts 82 and 84 through spur gears 226A and 226B, respectively. As 
with all other arrangements, coaxial output shafts are interconnected 
through rotational direction reversing means 88 (see FIG. 1) for rotation 
of the shafts in counterrotating directions. Although not required, 
oscillating shaft 202 may also be connected to output shafts 82 and 84 
through one-way clutches 228A and 228B, respectively, which may be of the 
same type as one-way clutches 110 and 112 shown in FIG. 1 and described 
above. One-way clutches 228A and 228B are in shunt with mechanically 
actuated clutches 200A and 200B, respectively. The one-way clutches 
operate in overrunning condition when shafts 82 and 84 function as driving 
shafts and shaft 202 functions as the driven shaft during, say, engine 
starting. On the other hand, mechanically actuated clutches 200A and 200B 
function to interconnect coaxial output shafts 82 and 84 to oscillating 
shaft 202 under all operating condition regardless of whether oscillating 
shaft 202 functions as the driving shaft or the driven shaft. 
As seen in FIG. 14, cams 218A and 218B are provided with a depression which 
allows for disengagement of the clutches when entered by levers 212A and 
212B, respectively. In the operating condition illustrated in FIG. 14, 
wherein shaft 202 is shown rotating in a clockwise direction, lever 212A 
engages the raised surface of cam 218A for engagement of clutch 200A, and 
lever 212B engages the depression in cam 218B for disengagement of clutch 
200B. When oscillating shaft 202 reaches the end of travel in the 
clockwise direction, cam 218A will have been driven through one-way clutch 
222A to the position wherein lever arm 212A enters the depression on the 
cam surface whereby clutch 200A is moved to the disengaged condition. When 
oscillating shaft 202 begins rotation in the counterclockwise direction, 
cam 218B is rotated through one-way clutch 222B. As cam 218B is rotated 
from the position shown in FIG. 14, lever arm 212B is pivoted so as to 
move clutch 200B into the engaged condition. While cam 218B is being 
driven by rotation of shaft 202 in the counterclockwise direction, cam 
218A remains stationary since one-way clutch 222A now functions in the 
overrunning mode. The operation continues such that clutch 200A is 
actuated into engaged condition during rotation of shaft 202 in a 
clockwise direction during which time clutch 200B is disengaged, and 
clutch 200B is actuated into engaged condition during rotation of shaft 
202 in a counterclockwise direction during which time clutch 200A is 
disengaged. With this arrangement, oscillating movement of oscillating 
shaft 202 in an amount sufficient to produce one complete revolution of 
cams 218A and 218B is required every time the cams are rotated through 
one-way clutches 222A and 222B, respectively. 
Reference now is made to FIG. 15 wherein another modified form of this 
invention is shown which includes an oscillating shaft 66 and 
counterrotating coaxial shafts 82 and 84 of the type shown in FIG. 1 and 
described above. Gear sets 102 and 104 connect oscillating shaft 66 to 
outer shaft 82, and gear sets 106 and 108 connect oscillating shaft 66 to 
inner shaft 84. As with the arrangement illustrated in FIG. 1, gear sets 
102 and 106 include one-way overrunning clutches 110 and 112, 
respectively, and gear sets 104 and 108 include electromagnetically 
controlled friction clutches 118 and 120, respectively. As with the other 
embodiments which include counterrotating coaxial shafts 82 and 84, means, 
such as means 88 shown in FIG. 1 are provided for interconnecting the same 
for simultaneous counterrotation thereof upon rotation of either shaft. 
When oscillating shaft 66 functions as the driving shaft, outer coaxial 
shaft 82 is intermittently driven in a counterclockwise direction, as 
viewed from the right, through one-way clutch means 110, and inner coaxial 
shaft 84 is intermittently driven in the opposite direction through 
one-way clutch 112, in a manner described above with reference to FIG. 1. 
Electromagnetically controlled friction clutches 118 and 120 are operated 
in the same manner as clutches 118 and 120 in the FIG. 12 arrangement. As 
seen in FIG. 16, switching control circuit 164 functions to alternately 
open and close switches 154 and 154A included in energization circuits for 
clutches 118 and 120. When ignition controlled switch 153 is closed, 
opening and closing of switches 154 and 154A controls engagement and 
disengagement of clutches 118 and 120, respectively. As noted above, with 
this arrangement, clutches 118 and 120 operate either for transmission of 
power from shaft 66 to coaxial shafts 82 and 84, or for transmission of 
power to shaft 66 from coaxial shafts 82 and 84, whereas overrunning 
one-way clutches 110 and 112 only function to transmit power from shaft 66 
to shafts 82 and 84, respectively. 
Referring again to FIG. 15, this embodiment of the invention is shown to 
include an overrunning clutch 230 and electromagnetically controlled 
friction clutch 232 in parallel in the connection of rotating shaft 84 to 
an output shaft 234. Output shaft 234 is, in turn, connected to the 
vehicle transmission 117. When rotating shaft 84 functions as the driving 
shaft, and shaft 234 as the driven shaft, rotation of shaft 84 by 
operation of the associated internal combustion engine is transmitted to 
shaft 234 by one-way overrunning clutch 230. When shaft 84 does not 
function as the driving shaft, one-way overrunning clutch 230 operates in 
the overrunning condition. As seen in FIG. 16, the energization circuit 
for electromagnetically controlled friction clutch 232 includes a switch 
236 under control of clutch control circuit 238. Clutch 232 is energized 
by closure of switch 236 which enables shaft 234 to function as the 
driving shaft and shaft 84 as the driven shaft. Engine compression may be 
controlled under certain conditions by controlling energization and 
deenergization of clutch 232 so as to control the extent of pivotal 
movement of the engine piston during oscillating movement thereof. Also, 
as described above, engine braking of the vehicle may be provided by 
engagement of clutch 232 when transmitting power from shaft 234 to shaft 
84. 
Another modified form of this invention is shown in FIG. 17, to which 
figure reference now is made. There, an oscillating piston engine which 
includes combustion unit 22, shaft 50 to which oscillating piston 52 is 
attached, and rotary valves 34 and 36 of the same type shown in FIG. 1 and 
described above is shown. Also, as with the FIG. 1 arrangement, 
oscillating motion of shaft 50 is transmitted to idler shaft 66 through 
sector gear 70 attached to shaft 50 and a cooperating gear 72 attached to 
shaft 66. Oscillating motion of idler shaft 66 is converted to 
counterrotating motion of coaxial shafts 82 and 84 which are 
interconnected by means 88 for simultaneous rotation of shafts 82 and 84 
upon rotation of either shaft. With this embodiment, oscillating shaft 66 
is adapted for connection to outer shaft 82 through sector gear set 244, 
and to inner shaft 84 through sector gear set 246. Sector gear set 244 
includes sector gear 244A affixed to oscillating shaft 66, and associated 
sector gear 244B affixed to outer coaxial shaft 82. Similarly, sector gear 
set 246 includes sector gear 246A affixed to oscillating shaft 66, and 
associated sector gear 246B affixed to inner coaxial shaft 82. During 
rotation of oscillating shaft 66 in a clockwise direction as viewed in 
FIG. 17, sector gears 244A and 244B engage for drive actuation of outer 
shaft 82 in a counterclockwise direction. Similarly, during rotation of 
oscillating shaft 66 in a counterclockwise direction, sector gears 246A 
and 246B engage for drive actuation of inner shaft 84 in a clockwise 
direction. Near the ends of pivotal movement of shaft 66 by the 
oscillating piston, both sector gear sets 244 and 246 are disengaged for 
transition of operation between the gear sets. 
When sector gear sets 244 and 246 are disengaged rotary movement of 
oscillating shaft 66 is limited by the above-mentioned stop means 74,74, 
and by cooperating detent means affixed to oscillating shaft 66 and 
rotating shafts 82 and 84. The detent means include first and second 
radially extending arms 252A and 254A affixed to oscillating shaft 66, 
which extend radially outwardly beyond spur gears 244A and 246A attached 
to shaft 66. Arms 252A and 254A are adapted for engagement with radially 
extending members 252B and 254B, respectively, attached to hubs 256 and 
258 affixed to counterrotating shafts 82 and 84, respectively. In FIG. 17, 
only one of the members 252B is visible. In FIG. 18, to which reference 
now is made, detent member 254B is shown pivotally attached to hub 258 for 
limited pivotal movement about pivot pin 260. Spring 262 resiliently 
biases member 254B for outward pivotal movement from shaft 84 into the 
full line position shown in FIG. 18. It will be apparent that in the 
rotary position of shaft 84 shown in FIG. 18, engagement between arm 254A 
and member 254B will limit rotary movement of shaft 66 in a clockwise 
direction until shaft 84 rotates a sufficient amount in the clockwise 
direction for disengagement of said arm and member. During this time, 
rotation of shaft 66 in a counterclockwise direction is limited by 
engagement of sector gear 70 with one of the stop members 74. When detent 
members 254A and 254B disengage, sector gears 244A and 244B will have 
reengaged. Detent member 252B is of the same type as detent member 254B 
shown in detail in FIG. 18. 
Operation of the sector gear and detent mechanism for converting 
oscillating motion of shaft 66 to counterrotating motion of coaxial shafts 
82 and 84 now will be described with reference to FIGS. 19A through 19J of 
the drawings. Operation of the combustion unit 22 for driving piston shaft 
50 and idler shaft 66 with an oscillating motion is the same as that 
described above with reference to FIGS. 1A and 1B, and that description is 
not repeated here. In FIG. 20, rate of rotation of oscillating idler shaft 
66 versus time is shown together with times A through J during a portion 
of an operating cycle, at which times shaft 66 is rotating in a clockwise 
direction (time A), is stopped at one end of travel (time B), rotates in a 
counterclockwise direction (times C through I) and is stopped at the 
opposite end of travel (time J). Shaft positions shown in FIGS. 19A 
through 19J correspond to respective times A through J in FIG. 20. 
In FIG. 19A, shaft 66 is nearing the end of rotation in a clockwise 
direction, at a point where sector gears 244A and 244B begin to disengage. 
At FIG. 19B, where motion of shaft 66 is stopped, sector gears 244A and 
244B of sector gear set 244, and sector gears 246A and 246B of sector gear 
set 246 are momentarily disengaged. However, pivotal movement of 
oscillating shaft 66 in a counterclockwise direction is prevented by 
engagement of arm 252A with member 252B of the detent means as illustrated 
in FIG. 19B. Only when shaft 82 has rotated to a position wherein arm 252A 
is disengaged by member 252B is shaft 66 free for pivotal movement in a 
counterclockwise direction. When arm 252A is released from engagement with 
detent member 252B, gear sector 246B engages gear sector 246A for rotation 
of attached shaft 84 in a clockwise direction by oscillation of sector 
gear 246A in a counterclockwise direction. Sector gears 246A and 246B 
remain in engagement throughout movement depicted from FIG. 19C through 
FIG. 19I. At the end of pivotal movement of shaft 66 and attached sector 
gears 244A and 246A in the counterclockwise direction, arm 254A attached 
to shaft 66 is adapted for engagement with member 254B attached to shaft 
84 to prevent the start of clockwise movement of shaft 66. Detent arm 254A 
is released from engagement with detent member 254B when shaft 84 rotates 
an additional amount, at which time sector gears 244A and 244B are again 
engaged. With this arrangement, oscillating shaft 66 may comprise the 
drive shaft and shafts 82 and 84 intermittently driven shafts, or shafts 
82 and 84 may function as drive shafts and shaft 66 as the driven shaft. 
As noted above, with conventional reciprocating piston engines wherein the 
pistons are connected to a crankshaft through connecting rods, torque 
supplied to the crankshaft is substantially zero at the time of ignition 
since the effective length of the crank arm is substantially zero at this 
time. With the above-described oscillating piston engine torque at output 
shafts 82 and 84 is primarily dependent upon forces on the pistons 
independently of the piston position. 
Advantages of this invention also may be obtained by converting 
reciprocating motion of a reciprocating piston engine to oscillating shaft 
motion, which motion then is converted to counterrotating shaft motion in 
a manner described above. Use of an oscillating piston engine is not 
required to obtain advantages of the present invention. In FIG. 21, to 
which figure reference now is made, a reciprocating piston engine is shown 
which includes first and second cylinders 264A and 264B and reciprocating 
pistons 266A and 266B within the cylinders. The cylinders are provided 
with spark plugs 268, and intake and exhaust valves, not shown, of 
conventional design. Pistons 266A and 266B are connected by connecting 
rods 270A and 270B to opposite ends of a rocking arm 272 which, in turn, 
is affixed to a pivotally mounted shaft 66'. Reciprocating motion of 
pistons 266A and 266B is converted to oscillating motion of shaft 66' in 
the direction of double headed arrow 274. Even at the top dead center 
positions of the pistons, substantial torque may be applied to shaft 66' 
by the pistons through the connecting rods 270A and 270B and pivotal arm 
272. Oscillating shaft 66' corresponds to shaft 66 in the above-described 
embodiments of the invention, and any of the above-described means for 
converting oscillating movement to rotary movement may be employed with 
the FIG. 21 arrangement for converting oscillating movement of shaft 66' 
to rotary movement. 
As noted above, the engine of this invention is provided with a 
conventional flywheel, not shown, to steady the speed of rotating output 
shafts 82 and 84. With the present invention, which includes oscillating 
shaft movement that is converted to rotary motion, it also is desirable to 
control the moment of inertia of the oscillating shaft during engine 
operation to facilitate complete oscillatory movement of the oscillating 
shaft. Means for controlling the moment of inertia of an oscillating 
shaft, such as piston shaft 50, is shown in FIGS. 22 and 23, to which 
figures reference now is made. There, oscillating engine shaft 50 is shown 
provided with a pair of diametrically opposed, radially extending, 
threaded arms 300A and 300B which carry weights 302A and 302B, 
respectively. The weights are axially movable along said arms for control 
of the moment inertia of oscillating shaft 50 about shaft axis 28. 
A frame 304 is attached to the thread arms 300A and 300B, which frame 
includes opposite end walls 306, 306 affixed to the outer ends of the 
threaded arms. Base and side walls 308 and 310, respectively, of the frame 
extend between the end walls 306, 306. In accordance with the present 
invention, weights 302A and 302B comprise reversible motors, each of which 
motors includes a rotatable armature 312 and associated stator 314. The 
armatures are provided with a threaded axial through hole threadedly 
engaged with the threaded arms 300A and 300B. The stators are prevented 
from rotation by slidable engagement thereof with a groove 316 formed in 
base member 308. The motors are axially movable along the threaded arms 
300A and 300B by rotation of armatures 312 upon energization thereof 
through motor input leads 318. They are of the reversible type for 
rotation of the armatures in either rotary direction and, therefore, 
movement of the motors in either direction along the threaded arms. As is 
well understood, the moment of inertia, I, of the mechanism increases as 
the weights, here motors 302A and 302B, are moved outwardly from the axis 
28 of oscillating shaft 50, and decreases as they are moved inwardly 
toward axis 28. In FIG. 23, the motors are shown positioned a distance "A" 
from axis 28. 
Means are provided for sensing, or measuring, the distance "A" for each of 
the motors. For purposes of illustration only, and not by way of 
limitation, position sensing means includes potentiometers 320A and 320B 
each of which comprises a resistance element 322 carried by wall 310 and 
associated movable contact 324 (FIG. 22) carried by the motors. The 
potentiometers are included in well known circuitry, not shown, the output 
from which provides a measure of distance "A" from oscillating shaft 50. 
Reference now is made to FIG. 24 wherein a flow diagram of operation of the 
variable moment of inertia system of this invention is shown. During 
operation of the engine the rate of rotation of one of the engine's 
counterrotating output shafts 82 and 84 is measured as indicated at 
measure RPM step 330, as by use of a tachometer, not shown. At step 332, 
the distance "A" of both weights 302A and 302B from the center of rotation 
28 is measured using measuring means 320A and 320B. Decision step 334 is 
entered where, for each weight, it is determined whether or not the weight 
should be moved closer to shaft 50 so as to reduce the moment of inertia 
of the oscillating system. As described above, at low operating speeds, 
the moment of inertia is increased to facilitate movement of the 
oscillating piston from one end of travel to the opposite end. By 
controlling the moment of inertia, the angle through which the piston 
operates is maintained substantially the same through all engine operating 
speeds. As engine speed increases from a low engine speed, decision step 
is affirmative in which case step 336 is entered for movement of the 
weights closer to shaft 50 for reduction in the moment of inertia. 
Operation then returns to step 330 from step 336. 
If step 334 is negative, decision step 338 is entered where, for each 
weight, it is determined whether or not the weight should be moved farther 
from shaft 50 so as to increase the moment of inertia. If decision step 
338 is affirmative, step 340 is entered where the weights are moved 
farther from shaft 50 for an increase in the moment of inertia. From step 
340, step 330 is reentered. If decision step 338 is negative, step 330 is 
reentered directly from step 338 and the entire process is repeated. 
Where the above-described variable moment of inertia system is directly 
attached to piston shaft 50, as shown in FIGS. 22 and 23, the weights 
undergo the same angular travel as the oscillating piston. If desired, the 
variable moment of inertia system may be connected to the oscillating 
piston through a gear train, or the like, to provide the system with a 
larger angular rotation and angular speed than that of the oscillating 
piston. With such an arrangement, smaller weights may be employed while 
still providing the system with the same kinetic energy as that of the 
illustrated arrangement. 
The invention having been described in detail in accordance with 
requirements of the patent statutes, various other changes and 
modifications will suggest themselves to those skilled in the art. For 
example, in the FIG. 15 embodiment, one-way clutches 110 and 112 and 
associated gear sets 102 and 106 may be eliminated from the arrangement in 
which case transmission of movement between oscillating shaft 66 and 
counterrotating shafts 82 and 84 would be solely dependent upon alternate 
energization and deenergization of clutches 118 and 120 Obviously, where 
electromagnetically controlled friction clutches are employed, the 
invention is not limited to use of the illustrated clutches. Many 
different forms of electromagnetically controlled clutches are known which 
are suitable for use in this invention. Similarly, other prior art one-way 
overrunning clutches may be employed, the invention not being limited to 
the use of one-way overrunning clutches of the illustrated type. In place 
of circular gears, elliptical gears may be used if desired. Also, 
operation of the engine using compression ignition is contemplated in 
which case air, not an air/fuel mixture, is supplied to the engine through 
inlet ports 44, and no spark plugs 58 are provided. High pressure fuel 
injectors are located at points that the spark plugs were located. When 
the sub-chambers reach substantially maximum pressure, minimum volume 
condition, fuel is sprayed into the sub-chambers, which fuel is ignited by 
the high temperature of the compressed air for start of the power phase. 
Additionally, the engine may be provided with a flywheel in the manner of 
conventional engines to smooth rotation of the counterrotating shafts. 
Instead of attaching gear 72 directly to idler shaft 66, such connection 
may include first and second meshing eccentric elliptical gears arranged 
so that idler shaft 66 is driven at a fastest rate when at the center of 
oscillatory movement, and at a slower rate when adjacent opposite ends of 
travel. Also, sector gear 70 may be provided with one or more arms which 
extend radially outwardly a distance greater than the radius of the gear 
sector, which arm, or arms, are adapted to engage relocated stop means at 
opposite ends of piston travel. It is intended that such changes and 
modifications shall fall within the spirit and scope of the invention 
defined in the appended claims.