|PERPLEXED ABOUT THE WANKEL ROTARY ENGINE|
|We could not understand why it does not perform the same or superior to the conventional piston engine... The Mazda rotary engine has a combustion displacement of ten to thirteen cubic inches. A lawnmower engine cylinder has the same displacement. The carburetor in the rotary engine is huge when you realize that it has three times the duration of a four cycle piston engine with its ports fully open throughout the stroke.
A 360 cubic Dodge truck engine displaces fourty five cubic inches each cylinder. The study of the exhaust valve show that the exhaust escapes through the equal area as a two by one quarter inch wide slot. The rotary engine has a three times duration for the stroke, has an exhaust port three times larger and about one quarter of the displacement.
The rotary engine requires more cooling than the reciprocating piston engine.
In the rotary engine the top dead center of the rotor rotates in the same direction as the eccentric shaft. therefore the duration of non torque producing combustion is three times longer.
The exhaust is released before the engine has completed its expansion cycle.
The greatest difficulty with the Wankel rotary engine results from the eccentric shaft turning three times faster than the rotor. This creates a problem similar to requiring a vehicle with a maximum speed capability of thirty miles per hour, having to push another vehicle ninety miles per hour.
It can be done in a complex manner. The slow vehicle has to travel at right angles to the fast vehicle using a bumper with a sixty seven and a half degree bumper and push the vehicle with a striking action.
In the Wankel engine there is a point whan the comusation momentarily applies pressure to the eccentric shaft. this is for a very short duration and more than ninety percent of the interior motion is the eccentric shaft pulling the rotor faster than the combustion can push it. Therefore ninety percent of the combustion pressures are not used.
Gearing the rotor to the eccentric shaft (e -shaft) as shown below will make the E-shaft and rotor work as a unit and take full advantage of the combustion cycles.
|The Wankel engine has similarities to the recoprocating piston four cycle engine with the advantage of fewer parts but a higher operating temperature and a longer top dead center position after detonation of the fuel. The rotor does the same function as the large piston rod journal to turn the crankshaft (e-shaft) Without the gear system shown below the combustion cannot rotate the rotor as it is locked against the stationary gear. The rotor is designed with a cavity in the center of each of the three surfaces to direct the combustion towards the center of the eccentric lobe of the e-shaft and the e-shaft action forces the rotor to engage it's teeth in the stationary gear to obtain rotation. There is a misconception about the leverage in the wankel engine that it is only from the center of the e-shaft to the center of the lobe. Study of the picture below will show leverage from the stationary gear contact point to the center of the eccentric to be 1.773" this is the same as a 3.5" stroke in a piston engine. When the shown gear is making a direct link from the rotor to the e-shaft the leverage varies between 4.773" to 5.773" the same as a piston engine stroke of 9.546" to 11.546".|
|UNDERSTANDING WANKEL ENGINE PRINCIPLES
To the right you see a Wankel engine design that has a planetary gear system that consists of as many as fifteen free floating nine tooth pinion gears (only one shown) connecting the e-shaft to the rotor.
The design also shows the stationary gear that is locked to the teeth of the interior rotor gear. The stationary gear without the planetary system included will not allow combustion pressures to turn the rotor. Therefore the rotation only comes from pressure being applied to the .591 inch throw of the e-shaft.
Also note that the top dead center of the e-shaft rotates the same direction as the rotor and circular motion is not assisted by combustion until after the rotor is at the position shown.
The operating principles of the Wankel engine consist of observing that the rotor completes one revolution every e-shaft revolution. During the revolution the rotor is forced to engage two thirds of its internal gear teeth with the stationary gear. This compells the rotor to be held up in its progerss by two thirds getting a gain of one third in the same direction as the e-shaft .
|IN fifteen revolutions of the e-shaft the center of the rotor will turn fifteen times (The significance of this is important when we want to understand the centrifugal forces within the rotor and for oil cooling of the rotor) The rotor will rotate five times on its center . The single pinion gear will complete six revolutions around the center e-shaft gear and it will complete four revolutions within the interior rotor gear.
When the pinion gear is viewed from within the orbit around the main journal it is spinning from a stationary point . The pinion gear is locked to the aforesaid stationary point by the e-shaft and the stationary gear meshing with the rotor..
|The Wankel engine as we know it does not have the disciplined functions that take place in the four stroke internal combustion engine.
Many years ago I was rebuilding a 360 cubic inch displacement Dodge truck engine. In the process I salvaged a burned exhaust valve that I later used to hold a panel in place on my 24" swing locomotive lathe.
In looking at the valve I realize that its function of removing the combusted fourty five cubic per cylinder displacement would be equal to removing the same displacement through a one quarter inch by two inch slot.
Mazda rotary engines have from eleven to fourteen cubic inches of dispacement and they have a three times greater duration to remove the exhaust and draw in the intake. Moving the exhaust port closer to the minor axis with modified ports would enable the use of the extra third of the power stroke.
|In respect for Bernard Maillard we present to incorporate all the above in a new engine design that uses the precision housing design specified in the Maillard patent. The intake and exhaust ports will utilize the hydraulics of fluid to separate the intake from the exhaust.They will be located in the area specified in the Maillard compressor patent. We suggest for the stationary gear to have sixty teeth that will mesh with the ninety gear teeth in the rotor. The center of the eccentric gear shaft lobe will also contain a sixty tooth gear that is meshed with up to fifteen fifteen tooth idle gears that mesh with the ninety tooth gear in the rotor. The leading and trailing bearings will be replaced with a planetary gear system that meshes with stationary gears in the front and rear end housings. The gears are designed to mesh with each other at the same velocity so will have none or very little wear. The engine interior will be in an oil bath with a centrifugal circulating system and will not require the high pressure oil pump. The ignition system will function by the use of strategically placed pressure switches.
This engine design is now known as
THE MAILLARD ROTARY ECCENTRIC GEAR ENGINE
|Note on the above drawing the four points on the diameter of the eccenrtic, there is a 3 inch vertical line from the six o'clock position.
The line is rotated thirty degrees when the position advances ninety degrees to the nine o'clock position.
The line is rotated thirty degrees when the position advances ninety degrees to the twelve o'clock position.
The line is rotated thirty degrees when the position advances ninety degrees to the nine o'clock position.
This is the patented system to design the precision Maillard Compressor housing.and it is not the two lobe epitrochoid that is used by Wankel rotary engine manufacturers today.
Note in the drawing to the left that it has a rotor that appears to be a copy of the Maillard patent drawing. It appears to be the same as the outside rotor with its top apex in center of the circle with the letter "d".
The geometry of the housing also appears to be a copy.
You will note in fig #3 of the Maillard patent that it containds instructions for drawing a rotor with what appears to be the eccentric diameter at the apex.
Note in the Wankel drawing of the rotary piston engine (DKM) below that his art has changed in the rotor design.
Felix Wankel never took the time to understand the complexity in the Maillard Patent drawings. never the less his method for drawing the housing produces a precision housing and not the two lobe epitrochoid in common use by rotary engine manufacturers today.
|To understand the working principles of the Wankel rotary engine we have found that for each quarter of a revolution of the e-shaft the rotor completes one third of a stroke|
|Photo number 1 below|
|In the picture to the left the right hand surface of the rotor has just completed the last third of the compression stroke and is about to start the power stroke.
The bottom surface of the rotor has just completed its first third of the exhaust stroke and is just starting the second third of the exhaust stroke.
The above surface has just completed its second third of the intake stroke.
|In a two rotor engine the opposite rotor is in the position shown in photo number 3|
|Photo number 2 below|
|In the picture to the left the bottom right surface of the rotor has just completed the first third of the power stroke.
The bottom left surface of the rotor has just started the last third of the exhaust stroke.
The top surface has just completed its last third of the intake stroke and is just starting its first third of the compression stroke..
|In a two rotor engine the opposite rotor is in the position shown in photo number 4|
|Photo number 3 below|
|In the picture to the left the bottom surface of the rotor has just completed the second third of the power stroke.
The left side surface of the rotor has just completed its last third of the exhaust stroke and is just starting the first third of the intake stroke.
The top surface has just completed its first third of the compression stroke and is starting the second third of it.
|In a two rotor engine the opposite rotor is in the position shown in photo number 1|
|Photo number 4 below|
|In the picture to the left the bottom surface of the rotor has just completed the last third of the power stroke.
The top left surface of the rotor has is just about to start the second third of the intake stroke.
The top right surface has just about to complete the last third of the compression stroke
|In a two rotor engine the opposite rotor is in the position shown in photo number 2|
|The above sketch was published by Mazda to promote its dynamic supercharging system.
It is obvious that they do not understand the principles that take place in the Wankel engine.
They show a flow away from the intake port during the intake stroke.
They show a flow into the intake port when the rotor is in its first third of the compression stroke.
|LINK TO PLANETARY GEAR INFORMATION|