Three displacement engine and transmission systems for motor vehicles

A main internal combustion engine powers a motor vehicle at 55 MPH. A smaller auxiliary engine powers the vehicle at slower speed. Both engines power at the same time for passing, hill climbing, etc. Either engine can be shut down (or idled) while the other engine powers. Thus, the engines operate more closely to best efficiency and this shall result in reduced fuel consumption (as calculated herein) and less air pollution. In a first species, the main engine transmits shaft power through a standard friction clutch and then to an ordinary transaxle consisting of torque converter, automatic transmission and differential. The auxiliary engine is mounted next to the transmission. Power from the smaller engine passes through an overrunning clutch and then by toothed belt and sprockets to the torque converter. A second species is identical to the first except an over running clutch takes the place of the friction clutch. In a third species, the main engine, main clutch, and transaxle are standard items mounted in the same location as in present single engine cars.

INTRODUCTION 
The power required to propel modern medium size cars on a level road at 55 
MPH (steady speed) is about 26 engine horsepower. At 25 MPH it is 5 H. P. 
Thus, present car engines spend most of their time operating at low power 
output where fuel economy is poor due to inlet air throttling, poor 
combustion, and more engine friction than necessary. 
Refer to the book, "The Internal Combustion Engine in Theory and Practice", 
Volume I, 2nd Edition by Professor Charles Fayette Taylor, the M. I. T. 
Press, Massachusetts Institute of Technology. Read the whole book but pay 
close attention to FIG. 12-11 which relates fuel economy at full load and 
part load; and see FIG. 12-16 which shows how fuel economy is related to 
brake mean effective pressure (B. M. E. P.) and piston speed. Refer also 
to pages 447 and 453 where Professor Taylor discusses and calculates the 
effect of gear ratio on fuel economy. 
It is known that an internal combustion engine has best fuel economy at 
full load, high B. M. E. P., and low piston speed. It is possible to raise 
B. M. E. P. and lower piston speed by going to a high gear ratio. However, 
at only 25 MPH in stop and go city traffic and with a single big engine, 
the gear ratio would get so high as to be impractical. 
Have you ever driven a car with a 5 speed manual transmission? As a driver, 
you soon learn not to go into 5th gear in city type driving. This is 
because the engine chugs along unsmoothly and with sluggish acceleration. 
At 25 MPH, the best way to raise B. M. E. P. (and the fuel economy) is to 
go to a small auxiliary engine and run it in a low enough gear so as to 
keep the engine RPM high enough for smooth running and good acceleration. 
Further, that small engine will be closer to full load compared to a 150 
HP single engine; and therefore its fuel economy will be better and with 
less air pollution. 
At 55 MPH, run on the main engine alone and with a fairly high gear ratio 
so as to improve fuel economy at that speed also. When you need more power 
for passing or hill climbing, make the simple conversion to two engine 
power effortlessly and on the fly. 
All engines illustrated herein are for both four stroke cycle and two 
stroke cycle interchangably. 
DISCUSSION OF PRIOR ART 
A good place to look for prior art (at the U.S. Patent Office) is in the 
examiner's search room under class 123 (internal combustion engines), 
digest 8 (multi-engine). The most pertinent prior art found was U.S. Pat. 
No. 4,638,637 Kronogard, et al. All of the prior art patents cited herein 
have provision for only two (not three) displacements. Kronogard 637 
teaches a 1/3 plus 2/3 power ratio but does it with a supercharger 23 and 
not by three displacements (column 2, lines 61 to 68 and column 3, lines 1 
to 8). Kronogard shows and specifies two equal size cylinders for each 
crankshaft (Column 2, line 63). Ormsby 2290703 has what he calls a 
"booster engine" 25 and that is all it is a booster. Ormsby does not 
mention (in 703) anything about running his engine 25 all by itself. In 
fact, Ormsby drives his sole water pump only when his main engine is 
running as can be seen in Ormsby's FIG. 3 and specified on page 2, column 
2, lines 3 to 8. Further, the Ormsby booster engine powers solely through 
an over-running clutch 29 and does not have a friction clutch or torque 
converter for use with the booster engine. This means therefore, that the 
Ormsby booster engine 25 cannot (by itself) start the vehicle from a dead 
stop, because internal combustion engines require a slip clutch of some 
sort to start a load. Further, Ormsby does not provide a compact two 
engine power plant capable of being located in the engine compartment of a 
passenger car. 
The following U.S. Patents all teach the use of a positive jaw clutch 
between the ends of two crankshafts: General Motors Corp. U.S. Pat. No. 
4,069,803, Volkswagon U.S. Pat. No. 4,373,481, and other U.S. Pat. Nos. 
4,367,703, 4,368,701, 4,389,985, and 4,394,854. Those positive jaw 
clutches are prime candidates for failure due to: impact upon engagement, 
failure to release due to stiction, and failure of the hydraulic or 
electric actuating means for the jaw clutch. The worst drawback to those 
positive jaw clutches is their location deep down inside the engine where 
access for their many repairs would require removal of one or both 
crankshafts. Synchronizing means is required before the jaw clutch can be 
engaged; and patent 854 shows a friction clutch 4 (between cam shafts) for 
that purpose. The use of a jaw clutch (in these prior engines) would 
result in two special engines and no standard production engine could be 
used. 
OBJECTS AND ADVANTAGES OF THIS INVENTION 
1. The first object is to provide a power plant with two separate and 
distinct engines whereby each engine can start and power the vehicle by 
itself and wherein both engines can power at the same time for maximum 
power when needed. A further object is that one engine shall have 
approximately twice the displacement of the other engine so as to provide 
three levels of displacement. 
2. A second object is to provide clutching and power transmission means 
such that each engine can start and power the vehicle by itself and 
wherein both engines can power at the same time for more power when 
needed. 
3. Use the auxiliary engine by itself when low power is required such as in 
slow city driving and traffic tie ups. 
4. At 55 MPH use only the main engine by itself and with a slightly higher 
gear ratio that in your average present car. 
5. The advantage of paragraphs 1 to 4 is reduced fuel consumption both in 
city type slow driving and also at 55 MPH. The reduced fuel consumption 
also means reduced air pollution. 
6. Run both engines under power at the same time when passing, hill 
climbing, etc. Thus my power plant is versatile; but does not have the 
continuous penalty of high fuel consumption (as with a single large 
engine). 
7. Another object is to select an auxiliary engine which will fit under the 
hood of a passenger car or truck. Most existing engine compartments are 
already crammed. A related object was to find a location and drive method 
for such an engine--not an easy task. 
8. Another object is to select an auxiliary engine which is well suited for 
the job. A two cylinder horizontal opposed engine is selected because (a) 
it has only two cylinders, (b) it fits well on top of the transmission, 
(c) it lays flat and permits a low hood line, (d) it has equally spaced 
power strokes and is thus smooth running, and (e) the reciprocating 
inertia forces are fairly well balanced, and (f) it is a common engine 
used in some motorcycles and this may lead to more rapid development. 
9. A good combination is to use four cylinders for the main engine and two 
cylinders for the auxiliary. The reasons for a two cylinder auxiliary are: 
(a) It will have half as many cylinders as the main engine and this gives 
an equal spread of three displacements, and (b) the two cylinder 
horizontal opposed has many qualities as was described in previous 
paragraph 8. 
The reasons for a four cylinder main engine are explained in paragraphs 10 
to 13 following. 
10. An advantage is that when cruising at 55 MPH, you are being powered by 
a single engine (not two engines). Further, that engine has four 
cylinders, is smooth running and powerful on its own. This is compared 
with General Motors U.S. Pat. No. 4,069,803 which has two crankshafts 
(serving a total of four cylinders) interconnected by a positive jaw 
clutch. Volkswagen U.S. Pat. No. 4,373,481 is the same. Which four 
cylinder engine would you rather have at 55 MPH--the G. M., the V. W., or 
my ordinary standard engine with the single crankshaft? 
11. Another object (as shown in FIG. 4) is to take an existing car or truck 
which has a single engine, clutch, and transmission. Leave all those parts 
substantially intact and where they are now located in the vehicle. Then 
combine my smaller auxiliary engine with same. Even retrofit into existing 
vehicles appears possible in some cases. Thus, my invention can use said 
parts which are already in common use and high production; and it is not 
necessary to redesign, retest and gear up to manufacture these parts. This 
will save cost, time, and hard earned reliability. 
12. The most popular four cylinder car engine today is the in-line 4, and 
the automobile giants are geared up to manufacture the in-line 4. 
Therefore, an object in FIG. 4 is to use the in-line 4. 
13. FIGS. 1 and 3 use a clutch in addition to torque converter; and this 
increases the axial length of the power plant. In a front wheel drive 
vehicle, the power plant is mounted transversely and thus overall length 
is limited. Accordingly, I have selected a Vee 4 main engine for use in 
FIGS. 1 and 3 because the VEE 4 is compact in axial length. 
14. Another object is to eliminate the need for a positive jaw clutch 
(between crankshafts) as taught by General Motors U.S. Pat. No. 4,069,803 
or Volkswagen U.S. Pat. No. 4,373,481 and four other patents listed 
herein. My two engines do not need to run in phased relationship with each 
other hence no need for a positive jaw clutch. The elimination of that 
complex part leads to simplicity, reliability, compactness, and use of 
standard engines. 
15. My power plant has a powerful two engine mode for passing other 
vehicles or for adding more power on a steep hill. This method is 
accomplished with no shifting of gears, no friction clutch operation, and 
no hesitation. This constitutes safety, simplicity, and convenience. 
16. My power plant has two modes of operation which I refer to as the "idle 
mode" and the "shut down mode". In the idle mode, one engine idles over 
slowly while the other powers. The advantage of idling is that it is not 
necessary to restart that engine and thus, it is more rapidly available 
for power when needed. Further, there is less wear on clutches due to 
restarts. 
The auxiliary engine uses only 0.9% of total fuel usage under all around 
driving conditions (based on idling tests reported herein). For these 
reasons, it is generally preferable to idle the auxiliary engine (instead 
of shut it down). 
17. If the driver so chooses, he or she may shut down the main engine while 
the auxiliary engine powers the vehicle. If so, this will result in a 
small saving of fuel and wear on the main engine. 
18. An object is to use the auxiliary engine to restart the main engine and 
thus there is less wear on the electric starting motor and battery. 
19. Many cars today have automatic transmission with torque converter and 
it provides driver ease and smooth starts. Therefore, an object is to 
incorporate this device into my two engine power plant and with as few 
changes as possible. 
20. Another object (in FIGS. 1 and 3) is to power the auxiliary engine 
through an over-running clutch instead of a more complex friction clutch. 
A related object is to also power the main engine through an over-running 
clutch as shown in FIG. 3. Again more compact and simpler than a friction 
clutch. 
Unlike Ormsby U.S. Pat. No. 2,290,703, my two engines can each power the 
vehicle (using over-running clutches) from a dead stop. This simple and 
compact feature is made possible as subsequently described. 
21. Another object (FIGS. 1 and 3) is to provide a locking device 26 to 30 
which permits both starting and braking of the auxiliary engine even 
though it drives through an over-running clutch 19. A related object is to 
be able to engage and disengage this device "on the fly". In my whole 
power plant, this device is the most likely to have a problem. 
Fortunately, it is located on top in the engine compartment where it can 
be easily worked on, if necessary. 
22. The sprockets 23 and 24 are mounted on the outside diameter of clutch 
hub and torque converter. Such mountings for sprockets save space and 
cost. Further, such mountings lend themselves to sprockets which are large 
in diameter thereby increasing life of toothed belt and its power 
capability. Other advantages of such a drive are: (a) No need to hold 
precise center distance as with an all gear system, (b) No lube oil needed 
and this goes right along with the dry outside diameter of present torque 
converters, and (c) Quiet. 
An alternative to the toothed belt is a chain. Easier to install in FIGS. 1 
and 3. 
23. It is expected that many (not all) city drivers will tend to run on the 
auxiliary engine along most of the time--so as to save fuel cost. As such, 
the main engine will be shut down (or idled). The main engine will thus 
have a longer calendar life than the engine in present automobiles. We 
would prefer to wear out the auxiliary engine and auxiliary clutch 
(instead of main engine and main clutch) for the following reasons 24 to 
26 inclusive. 
24. The auxiliary engine is on top and accessable where it is easy to 
remove. No need to go underneath. So light, a chain hoist may not be 
necessary. 
25. The auxiliary engine has only two cylinders and thus less cost to 
overhaul or exchange. 
26. The auxiliary clutch is accessable. No need to go under or to drop a 
heavy greasy transmission. In the case of FIGS. 1 and 3, the auxiliary 
clutch is merely a sprag type over running clutch and (unlike a friction 
clutch) it would probably last as long as the vehicle itself. 
27. The previous advantages (24 to 26) are made possible because two 
separate and distinct engines are employed. This is counter to prior art 
which uses a common cylinder block and/or two crankshafts interconnected 
(end to end) with a positive jaw clutch. 
28. An object is to drive electric alternater, water pump, and air 
conditioner with either/or both engines. A pulley and belt 45 are provided 
for this purpose. If this objective were not secured, the vehicle would 
not fully operational on either/or both engines. Ormsby U.S. Pat. No. 
2,290,703 drives water pump from main engine only--see "Discussion of 
Prior Art". 
29. An advantage is that should either engine fail, the driver can (in some 
cases) use the remaining engine to reach home or a repair shop. Such a 
feature contributes to safety because a stalled vehicle at the side of a 
busy highway, freezing isolated road, or criminal neighborhood is an 
unsafe situation. 
30. A cost reducing objective is to use only a single electric starter 
motor and its associated ring gears. 
A related objective is as follows: If the main engine should fail to start 
(using the electric starter motor), it is still possible (under most 
situations) to crank over both engines (at the same time) using the same 
single electric starter motor and therefore start the auxiliary engine. 
Both engines have their own fuel and ignition systems and therefore the 
chances of both engines failing to start is much less than with a single 
engine. Once either engine starts, there is plenty of cranking power to 
start the other engine (or drive home on one engine, if necessary). 
31. My power plant uses two engines and therefore you are concerned about 
cost. There are still only 6 cylinders, total. The main engine shall last 
longer as per paragraph 23. For other cost reducing features, refer to 
paragraphs 5, 11, 12, 20, and 35. For safety and convenience, refer to 
paragraphs 15, 29, 30, and 33. Also, less air pollution. 
32. Another object is to use only one of each of the following items in 
said motor vehicle: transmission, differential, transaxle torque 
converter, water pump, radiator, thermostat, fan, exhaust system, electric 
generator, starter motor, battery, fuel pump, and one electronic 
controller. However, each engine should have its own lube oil pump, lube 
system, ignition system, and fuel injection (or carburation) system. 
33. An added use is in a recreational camper vehicle. While the camper is 
parked, drive generator, air conditioner, etc. using only the auxiliary 
engine. 
34. When both engines are powering at the same time, there is a possibility 
of two cylinders firing at the same time. To relieve a possible problem, 
the sprocket 23 is made with one or two teeth less than sprocket 24. Thus, 
if two cylinders should fire at the same time, they will not do so on the 
next rotation. Keep in mind that powering both engines at the same time 
occurs only a small fraction of total running time. 
35. With my two engine power plant, it appears likely that the transmission 
could have on less gear ration (less cost) than in a single engine car. 
This is because when you change displacement (on the fly), it is like 
changing gear ratio.

DETAILED DESCRIPTION OF FIGS 1 AND 2 
A four cylinder 90 degree Vee engine 1 drives an automotive friction clutch 
2 which in turn drives a fluid coupling or torque converter 3. This last 
item is the ordinary automotive three element type which has blades 
turning in fluid. In technical terms this is sometimes referred to as 
"hydro kinetic". The torque converter is part of an ordinary automatic 
transmission 4. The stub shaft 5 is bolted to the input end of the torque 
converter; and the stub shaft is piloted at 6 into the end of the main 
engine crankshaft. The transmission (as usual) contains an output gear 7, 
and idler gear 8 which drives an ordinary ring gear 9 which in turn drives 
the differential 10. Drive shafts 11 extend out each side of the 
differential so as to drive vehicle front wheels. The combination of 
torque converter, transmission, ring gear, differential, and drive shafts 
are commonly known as a "transaxle". 
Mounted on top of the transmission is an auxiliary engine 12 having two 
horizontal opposed cylinders 13. The crankshaft 14 has cranks 15 and 16. 
The con rod big ends 17 and 18 ride on the crank pins. See FIG. 5 for a 
plan view of a similar engine. 
Item 19 is an over-running clutch which consists of an inner race (keyed to 
the crankshaft) outer race 20, ball bearings and sprags 21. The 
over-running clutch transmits rotary power in one direction and freewheels 
the other. 
A hub 22 surrounds the outer race and is bolted to same. A sprocket 23 is 
mounted to the O. D. of the hub and rotates therewith. A similar sprocket 
24 is mounted to the O. D. of the torque converter and rotates therewith. 
A Toothed belt 25 interconnects the two sprockets. 
The plunger 26 is splined at 27 to the hub. The plunger has several tapered 
dogs 28 which engage with tapered slots 29 when the plunger is pushed in. 
A coil spring 30 retracts the plunger when not engaged. 
The main clutch 2 contains the usual lever 31, throw-out bearing 32, 
diaphram spring 33, splined friction clutch disk 34, and flywheel 35. 
Referring to FIGS. 1 and 2, the main engine 1 is not novel in itself. It is 
compact in axial length and thus well suited for FIG. 1 where axial space 
is at a premium (especially where both a friction clutch 2 and torque 
converter 3 are employed). The engine has the following standard parts: 
crankshaft 36, connecting rods 7, pistons 38, and counterweights 39. Each 
pair of water cooled cylinders 40 are cast integral and bolted to the 
crankcase. A sprocket and toothed belt 41 are for driving cam shafts, 
water pump, etc. Not shown (for either engine) are cylinder heads, valves, 
ignition, fuel systems, etc. because these parts are all standard. 
OPERATIONS DURING A TRIP 
The following narrates various driving conditions and how they are handled. 
Start both engines as follows: place the usual hand control lever in 
"K". Push plunger 26 inward by means not shown. Keep pressure on the 
plunger so as to urge it inward. Engage main clutch 2 by means of 
hydraulic cylinder 42 or foot pedal 43. Turn key to start. An electric 
starting motor will engage ring gear 44 so as to start rotation of main 
engine 1, main clutch 2, torque converter 3, sprockets 23 and 24, belt 25 
and hub 22. Upon the first few degrees of rotation, the tapered dogs 28 
will engage tapered slots 29 so as to rotate crankshaft 14. Both engines 
are thus cranked over and only one electric starter motor is needed. 
The first leg of our trip is in the city so the main engine will be shut 
down (or idled) and the main clutch 2 disengaged. As an option, the 
plunger 26 can be left engaged in which case the auxiliary engine will 
provide the usual engine braking effect when your foot lets up one the 
gas. Next, place hand control lever in "D", give the auxiliary engine a 
little gas and we are moving on two cylinders. 
At a traffic light, let off the gas and brake to a stop. You don't need to 
touch the hand lever and the auxiliary engine idles over slowly. It is 
able to do this even though the over-running clutch 19 has not released, 
and this is because the torque converter acts like a clutch itself and 
permits idling. When the traffic turns green, release the brake, give the 
auxiliary engine a little gas (with foot pedal) and our vehicle pulls 
smoothly away. This vehicle has two engines, but it is almost like driving 
an ordinary car. 
We are now out of city traffic and would like to cruise at 55 MPH. Our next 
step is to convert from auxiliary engine to main engine; and we do this 
"on the fly" without stopping the vehicle. Release plunger 26 and spring 
30 snaps it back. Engage main clutch 2 slowly. The main engine will now be 
started by either of two ways: (a) the auxiliary engine will start the 
main or (b) power from the wheels will be fed backwards through the torque 
converter so as to start the main engine. If (b) should prove to be a 
rapid rough start, the hydraulics of the transmission could be modified to 
prevent (b). Such a rough start is unlikely because a torque converter has 
a smooth flow of torque. 
As an option, the main engine could have instead been idling--discussed 
further on. Give the main engine some gas and let off the gas to the 
auxiliary engine which will now idle. There is no need to worry about 
disconnecting the auxiliary engine from the drive train because the 
over-running clutch 19 has automatically taken care of this. 
Next, we are running at 45 MPH on a winding canyon road. A slow driver is 
ahead. Finally we see that the road ahead is clear to pass so here is what 
you (the driver) do: Apply accelerator pedal to both engines at the same 
time. (There may be two such pedals depending on control method). The 
auxiliary engine had already been idling so it will power up right away 
with no hesitation. When the auxiliary engine reaches the speed of the 
main engine, the over-running clutch 19 will engage automatically and the 
two engines will power us past the slower vehicle with plenty of power. 
This powerful passing mode (with no hesitation or gear shifting) is both a 
convenience and a safety feature. Unlike the ordinary car, displacement is 
added for passing or climbing steep hills. 
Now that we are safely past that car, let off on the gas to the auxiliary 
engine (it goes to idle) and we are cruising at 55 MPH on main engine 
alone. 
Next, we come to a steep upgrade hill and need more power. Apply the gas 
pedal to the main engine. If this is not sufficient, also apply gas pedal 
to the auxiliary engine. If this is still insufficient, the automatic 
transmission will (on its own) switch to a lower gear ratio. 
Next, we come to a steep downgrade. Keep the main clutch 2 engaged and main 
engine compression will restrain the wheels. If needed, shift hand lever 
to "3nd" for more engine braking. 
Next, we pull onto the Los Angeles freeway and it is an extremely hot day. 
There is no wind and a pall of smog has been hanging over the city for 
days. To our dismay, we encounter a traffic pile up. So then you declutch 
main engine and shut it clear off. We are now inching along on auxiliary 
engine. The torque converter is a nice feature here as you don't have to 
keep working a friction clutch. Our water pump and air conditioner are 
working because Vee belt 45 drives these from either or both engines. We 
creep along in air conditioned comfort. 
We look at other cars in front and each side of us. These cars have from 
four to eight cylinders. We are the only car running on only two cylinders 
and we are consuming fuel at a rate less than half. Yet, our car is medium 
size. Those big cars are belching noxious exhaust fumes and it hangs in a 
pall in this canyon freeway. 
After a half hour of bumper to bumper traffic we pull off the freeway and 
this is the end of our trip. We have consumed less fuel than other 
vehicles as next calculated and tabulated. Further, our transmission has 
shifted gears fewer times than others. 
CALCULATED PERFORMANCE 
This calculation is based on a main engine of four cylinders of 3.5 inch 
stroke and 4 inch bore. The auxiliary engine has two cylinders of 3.5 inch 
stroke and 4 inch bore. The first part of the calculations are for level 
road performance running at steady speed with no stops. The results are 
tabulated as follows: 
__________________________________________________________________________ 
CALCULATED PERFORMANCE 
NO OF 
ACTIVE ENG. REVS 
ENG. 
MILES ROAD 
CASE 
MPH BMEP 
CYLS. 
H.P. 
PER MILE 
RPM PER GAL. 
CONDITION 
__________________________________________________________________________ 
A 55 38.7 
6 26 2200 2017 
21.2 LEVEL 
B 55 58 4 26 2200 2017 
22.7 LEVEL 
C 55 72.6 
4 26 1760 1613 
24.4 LEVEL 
D 55 48.4 
6 26 1760 1613 
22.3 LEVEL 
E 55 96.7 
2 26 2640 2420 
24.9 LEVEL 
F 25 13.6 
6 5 2640 1100 
21.4 LEVEL 
G 25 40.9 
2 5 2640 1100 
50.8 LEVEL 
H 25 20.5 
4 5 2640 1100 
35.12 LEVEL 
I 55 100 4 75 3686 3376 
8.2 UP 
HILL 
J 55 66.6 
6 75 3686 3376 
7.59 UP 
HILL 
__________________________________________________________________________ 
A sample calculation for CASE A is as follows: Engine HP at 55 MPH for a 
modern streamlined medium sized automobile of about 3500 LB weight on a 
level road=26 HP--from various sources. Engine revs per mile=2200. 
Averaged from "Consumer Reports" magazine, April, 1991. Engine 
speed=2200.times.55/60=2017 RPM. Piston 
speed=2017.times.3.5.times.2/12=1176 FT/min. Total piston 
area=6.times.0.7854.times.16=75.4 in.sup.2. Power strokes per min with 4 
stroke cycle=2017/2=1008 B. M. E. 
P.=HP.times.33000.times.12/LAN=26.times.33000.times.12/3.5.times.75.4.time 
s.1008 =38.7 PSI. Brake specific fuel consumption=0.6 LB/HP HR. 
Miles/gallon=55.times.6/26.times.0.6=21.2 MPG. 
CONCLUSIONS ON CALCULATIONS 
Compare CASE F vs. CASE G. Here is where two cylinders do the work of six 
cylinders; and this is where the biggest fuel savings are. The mileage on 
2 cylinders is 50.8 MPG and the BMEP is a conservative 40.9 so the engine 
is not being overworked. This is compared with 21.4 MPG for six cylinders 
(single engine vehicle). 
There is a lot of 25 MPH driving where two cylinders will do just fine. As 
part of this work, your author rented a three cylinder Geo Metro for two 
months. With one passenger, we accelerated up a long hill at 55 MPH with 
power to spare. No vibration or roughness. All around mileage 40 MPG. The 
Metro has 61 cubic inch displacement. This is compared with my two 
cylinder auxiliary engine herein which has 88 cubic inches. 
If you are apprehensive about driving on only two cylinders, keep in mind 
that in an instant (on the fly) you can add up to four more cylinders if 
you need them. 
CASE F vs. CASE G. Fuel saving =(50.8-21.4)/21.4=137%. 
CASE A vs. CASE C is based (in part) on the proposal that my vehicle can 
have a higher ratio in high gear than in a single engine car. Such high 
ratio (in the transmission and/or final drive) is permitted (in my 
vehicle) because slow city type driving is now powered by the auxiliary 
engine using low ratio sprockets as shown in FIGS. 8 and 9. A further 
reason (for the high ratio) is that you always have the option to go to 
six cylinders (in an instant) if needed. Thus, at 55 MPH (using main 
engine) there will be a 15% fuel saving due to (a) Higher gear ratio and 
(b) Run on four cylinders instead of six. 
TO IDLE OR SHUT MAIN ENGINE OFF WHILE UNDER WAY 
Your author has made several tests (as follows) on actual engines to 
determine the amount of fuel consumption under idling conditions: The 
first test was made Aug. 17, 1991 on a 1989 Ford Escort. This vehicle has 
a four cylinder 1.9 liter engine with manual transmission and electronic 
fuel injection into a throttle body. Outside air temperature 56.degree. F. 
Engine tachometer read 900 RPM; and this was the lowest RPM I could get by 
releasing accelerator pedal rapidly. Fuel used in a one hour idling test 
was 535 milliliters (0.14 gal.) of no lead gasoline. Fuel was measured by 
filling the tank before and after to the very top of the inlet pipe; and 
without stopping the engine. That 900 RPM seemed high. Therefore, your 
author went to the local Ford dealer to see if it could be reduced. The 
shop foreman said 900 RPM was normal and that there was no adjustment to 
reduce that; so I did not pursue that matter further. 
In a second idling test, the tachometer of a 6 cylinder carbureted small 
tractor engine read 400 RPM with no effort to reduce it further. That 
engine ran very smoothly at 400 RPM with no tendency to stall. 
In a third idling test, a 1978 Ford straight six of 300 cubic inch 
displacement and manual transmission used 1500 milliliters (0.39 gal.) of 
gasoline in one hour. In this test, the transmission was placed in neutral 
and the foot pedal for the clutch was blocked in the disengaged position. 
CONCLUSIONS ON IDLE OR SHUT DOWN 
(a) Assume 450 RPM idle speed for both engines. 
(b) If you shut down the auxiliary engine (instead of idle), the fuel 
saving is calculated to be 0.9% of total fuel usage under all around 
average driving conditions. Therefore, it does not appear worthwhile to 
shut down the auxiliary engine (although it could be done). 
(c) If you shut down the main engine (instead of idle), the fuel saving is 
calculated to be 1.8% of total fuel usage under all around average driving 
conditions. 
(d) In view of the preceeding, many drivers may choose (at times) to idle 
both engines so as to take advantage of the more rapid response for added 
power when needed. 
(e) Some city drivers may choose to run all day on just the auxiliary 
engine (For fuel economy). In that case, shut the main engine down. 
(f) The preceeding paragraphs (b) and (c) pertain only to shut down vs. 
idle and should not be confused with overall fuel savings in my two engine 
system as set forth in the calculated tabulation. 
DETAILED DESCRIPTION OF FIG. 3 
This Figure is identical to FIG. 1 except the main friction clutch 2 has 
been replaced with a sprag type over-running clutch 47. The inner race 48 
(for the sprags) is keyed to stub shaft 49. A larger pilot bearing 50 
(roller) has been added. Identical parts common to FIGS. 1 and 3 are given 
the same numbers. 
Operation of FIG. 3 is as follows: Engage plunger 26. Start both engines at 
the same time with the single electric starter motor. Release plunger 26. 
You are powering on auxiliary engine alone and the main engine is idling. 
You need more power. Gas the main engine and let off on the auxiliary. The 
main engine applies more power with no hesitation, shifting of gears, or 
friction clutch operation. 
You are accelerating up a steep hill and need more power than the main 
engine can provide. Gas the auxiliary. Again no hesitation or gear 
shifting. 
The FIG. 3 construction is more compact, simpler, and lower cost than FIG. 
1. Further, the response time (to change number of active cylinders) is 
faster. In FIG. 3, the main engine cannot be restarted by means of the 
auxiliary engine; and therefore, (under average driving conditions) the 
main engine will be idled when not under power. If, however, the car is 
going to be operated all day on its auxiliary engine, then shut main 
engine down. 
A drawback to FIG. 3 is that the main engine cannot provide braking effort 
as shown. However, the auxiliary engine is capable of braking--with 
plunger 26 left in the engaged position. If necessary, the plunger 26 can 
be engaged "on the fly" as follows: (a) Reduce the speed of the main 
engine to idle. (b) Power the auxiliary engine slightly so it is actually 
propelling the vehicle and thus sprag clutch 19 is in the engaged position 
and thus there is no relative motion between parts 28 and 29. (c) Engage 
plunger 26. Automatic controls should be provided for this procedure so as 
to prevent tooth impact and consequent damage. 
DETAILED DESCRIPTION OF FIGS 4 AND 5 
The main engine 51 has four in-line cylinders 52 with pistons 53, con rods 
54, crankshaft 55, and spark plugs 56. The main engine drives an ordinary 
friction clutch 57 with friction disk 58, pressure plate 59, coil springs 
60, throw out bearing 61, flywheel 62, and starter ring gear 63. Coupled 
to the clutch is a four speed manual transmission 64 and its parts are: 
input shaft 65, countershaft 66, output gear 67, and reverse gear 68. 
Also, shown are the other usual gears and shifters. 
An auxiliary engine 69 (mounted on top of the transmission) is two cylinder 
horizontal opposed. The two throw crankshaft 70 drives two con rods 71 and 
two recip pistons 72 in water cooled cylinders 73. Cylinder heads, valves, 
ignition, etc. are not shown for either engine as these are standard 
items. 
Mounted on the end of crankshaft 70 is a friction clutch 74. See FIG. 5, 
too. The friction disk 75 is splined to the crankshaft. Pressure plate 76 
is pressed into the pulley/flywheel housing 77. Movable pressure plate 78 
is splined to the pulley housing. Diaphram spring 79 holds the pressure 
plate tightly against disk 75. The throw out bearing 80 actuates pins 81 
which in turn push against heavy washer 82, which in turn bears against 
the diaphram spring so as to disengage the clutch. 
A sprocket 83 is mounted to the O.D. of the housing. A second sprocket 84 
is mounted on and rotates with input shaft 65. Toothed belt 85 
interconnects the two sprockets for power transmission. When clutch is 
disengaged and crankshaft not rotating, the pulley housing rotates freely 
on ball bearings shown. Vee belts 86 and 87 are for driving generator, 
water pump, etc. from either or both engines. 
A prime feature of FIG. 4 is that the engine 51, clutch 57, and 
transmission 64, are standard items in existing automobiles. Further, 
these parts are in their original locations in the engine compartments. 
This means therefore that the only major additions (for two engine 
operation) are the auxiliary engine 69, clutch 74, sprockets, and belt. 
Your author has examined a number of existing cars and retrofit appears 
possible (at least for a test vehicle). There will be some "shoe horning" 
involved. 
Operation of FIGS. 4 and 5 is similar to FIGS. 1 to 3 except there are two 
controllable friction clutches and no over-running clutches. Both systems 
have their pros and cons. 
DETAILED DESCRIPTION OF FIG. 8 
This is a small scale end view of FIG. 1 in which the auxiliary engine has 
been shifted to the side of the transmission (a less preferred location). 
For clearness, only the crankshaft 14, connecting rods 17-18, and pistons 
of the auxiliary engine are shown. A feature in FIG. 8 has to do with 
sprockets as follows: You are driving in the city at 25 MPH, on the 
auxiliary engine. The transmission 4 is an automatic and it has (by 
itself) shifted to high gear. The sprocket 23A is smaller than sprocket 24 
and this gives a lower drive ratio for the auxiliary engine. This permits 
the auxiliary engine to rev up faster and thus permits more rapid 
acceleration and without the chugging action of a vehicle running too slow 
at too high a gear ratio (especially when running on only two cylinders). 
The same sprockets and belt (with the lower ratio) will also come in handy 
as an assist for hill climbing and passing. As an option, use the same low 
ratio sprockets in all the species herein. 
DETAILED DESCRIPTION OF FIG. 9--REAR WHEEL DRIVE 
Many parts in FIG. 9 are identical to those in FIGS. 4 and 5; and such 
parts are given the same reference numbers. Main engine 51 drives main 
clutch 57. Clutch shaft 88 drives manual transmission 89. Auxiliary engine 
69 (with clutch 74 and sprocket 83) is mounted on top of transmission 89. 
A sprocket 90 is keyed to shaft 88. Toothed belt 91 interdrives the two 
sprockets. The sprocket 90 has a larger diameter than sprocket 83 so as to 
provide a speed reduction--the advantages of which were described for FIG. 
8. Transmission shaft 92 is piloted (with sleeve bearing 93) into clutch 
shaft 88. The gears 94 and 95 drive lay shaft 96. The various other gears 
shown are all standard. The standard shifter synchronizers are not 
illustrated. Item 97 is part of a universal joint leading to the rear 
wheels. Either or both engines can drive the vehicle. A nice feature here 
is that the clutch shaft 88 serves a double function. It conveys shaft 
power from main clutch to transmission, and also provides a convenient 
drive location for sprocket 90. 
This FIG. 9 will probably make the easiest retrofit conversion (from an 
existing single engine vehicle) since the only changes to the drive line 
are: weld a 2 inch extension into the center of clutch shaft 88, move 
transmission 89 rearward two inches, and shorten the final drive shaft two 
inches. 
DETAILED DESCRIPTION OF FIG. 10--REAR WHEEL DRIVE 
Most of the parts of FIG. 10 are identical to those in FIGS. 1 and 3; and 
such parts are given the same reference numbers. Main engine 1 drives 
automatic transmission 98 via main clutch 2, stub shaft 5, and torque 
converter 3. Auxiliary engine 12 drives transmission 98 via over-running 
clutch 19, hub 22, sprockets 23-24, toothed belt 25, and torque converter 
3. Item 99 is part of a universal joint for drive shaft leasing (as usual) 
to differential and rear wheels. 
Operation of FIG. 10 is identical to FIG. 1 except for rear wheel drive. 
MODIFICATIONS NOT SHOWN 
All species illustrate two sprockets and a toothed belt. However, such 
drive could also be two sprockets and a chain; or it could be two pulleys 
and belts. Therefore, some of the claims use the word "pulley" and this is 
a generic term. If the pulley has teeth on it, then its more specific name 
is sprocket and it is used with a chain or toothed belt. The term "endless 
flexible element" is a generic name which includes chain, belts, and 
toothed belts. 
A torque converter is a specific class of fluid coupling. All the 
preceeding definitions shall apply to and have the same meaning in the 
appended claims. 
Other possible (less preferred) engines are Vee 6, three cylinder in-line, 
and two cy linder in-line. 
Other possible clutches are: oil flooded friction, piston actuated 
friction, electromagnetic, over-running wrapped spring, hydrostatic, dry 
powder or shot against wavy disk, and Electro-Rheological Fluid (ERF). 
The locking mechanism 26 to 30 could be replaced by a friction clutch such 
as shown at 74 in FIG. 5. In this case the sprags 21 would be placed 
around the crankshaft and just to the left of clutch disk 75. In this case 
the sprag clutch and the friction clutch would operate in parallel such 
that either or both could drive. 
ADDENDUM 
Referring to FIGS. 1 and 3, the top half A23 of the sprocket is illustrated 
smaller than bottom half 23. This is to illustrate an option. That is, the 
sprocket can be small A23 or larger 23. An object and advantage here is 
that the preferred A23 version is smaller than sprocket 24 and thus a 
speed reducer (torque increaser) is provided. See FIG. 8 for same speed 
reducer. This will permit engine 12 to rev up faster and accelerate faster 
in 25 MPH city type traffic--as was more completely described in "CASE A 
vs CASE C". 
Referring to FIG. 1, the line 46 illustrates the engine compartment which 
encloses my two engine power plant. 
It is understood that various modifications of my inventions may be made 
and my invention is only limited by the scope of the appended claims.