Paul, Do you know anyone who could act as a consultant to a
company that is developing a new type of rotary engine? They need
help with seals. Mazda seals won't work. Thanks. jd

No I don't. If they would consult with me I would tell them to
forget it. Rotary engines have been around since the 1500's. Felix
Wankel studied the heck out of them. I have his very comprehensive
and detailed paper on the subject.

Like Kenichi says; a new rotary has a snow balls chance in hell of
working given the billions Mazda has already invested in the
Wankel. What Mazda has achieved is quite remarkable.


Paul Lamar

--------------------------------------------------

By Kenichi  Yamamoto from his book "Rotary Engine" 1981

1.3 REQUIREMENTS FOR A PRACTICAL ROTARY ENGINE Although various
types of rotary engines have been developed to date, there are few
that do not qualify as internal combustion engines or do not
qualify as a practical engine even if they satisfy the
qualifications of an internal combustion engine. The requirements
for a rotary engine to be qualified as a practical internal
combustion engine can be summed up in the following five items. The
practicality of various ideas on rotary engines can be judged by
evaluating them by these criteria:

(1) Every moving part, including the timing mechanism, should make
a rotating motion. A mechanism having a reciprocating inertia will
increase mechanical noise and vibration, and will work against high
speed and high revolution. [In addition mechanisms that
reciprocate generate reversing loads. Reversing loads lead to
reversing stresses. Reversing stresses lead to metal fatigue and
limited life. The Wankel rotary engine has no reversing stresses
therefor the life of the major parts such as the eccentric shaft
and rotor are unlimited unlike, crankshafts, connecting rods,
pistons and poppet valves. Paul Lamar] Accordingly, structures
that require intake and exhaust valves and mechanisms using the
rotors oscillatory motion are not desirable.

(2) Gas seals or the working chamber should be three
dimension-ally reliable. The gas seal mechanism of a rotary engine
should be constituted by connecting the individual seals three
dimension-ally. Among the many ideas we come across are those that
don't show such three dimensional thoughts.

(3) Appropriate gas exchange of intake and exhaust should take
place. Together with having a mechanism that can correctly open and
close the ports, sufficient time for intake and exhaust should be
provided especially for high speed and high revolution. Among the
ideas on rotary engines, there are some that ignore this point.

(4) Every component part should have the strength to endure
high speed and high pressure. As the component parts are exposed
to high pressure, high sliding velocity and high heat load, every
part should have sufficient allowance in size and in shape.

(5) Sufficient cooling and lubrication should be provided. In
order to qualify as an internal combustion engine, although this is
related to above (4), durability against high heat load, high
sliding velocity, etc. are required. Therefore, the structure
should be simple, and the ideas on rotor cooling, lubrication of
seal parts, and oil seal structure should be those that are given
adequate thought. Also, it is desirable for a practical rotary
engine to have a simple and compact structure. When we evaluate
the various type's of rotary engines devised to date in view of
the above mentioned requirements, the NSU Wankel type rotary
engine is the engine that best satisfies the above mentioned
requirements.


----------------------------------------------------------- History
of the invention of the rotary engine by Julian Marsh

1588 Ramelli, an Italian engineer invented a water pump which
continues to be used in oil pumps and compressors.

1636 Pappenheim, a German engineer invented the gear pump which is
still used to lubricate engines. This gear pump made it possible
to dispense with the reciprocating slide valves used by Ramelli.
[Fig 3]

Pappenheim drove his machine by an overshot water wheel set in
motion by a stream and was used to feedwater fountains. The
emperor Ferdinand II granted him a privilege - the equivalent of a
patent in respect of this invention.

Even in the 17th century, engineers were trying to solve the
problem of leak-proofing between moving parts and this problem
continues to be the Achilles heel of the rotary piston engine
although Mazda would seem to have reduced this problem to
manageable proportions.

1650 Otto von Guericke built a vacuum pump which employed leather
washers to prevent leakage between cylinder and piston.

1782 James Watt who invented the steam engine?s connecting rod
crank mechanism which made it possible to convert the piston?s
reciprocating motion into rotary motion designed an oscillating
piston machine in which a wing-shaped rotary blade performed an
almost complete revolution uncovering inlet ports in a chamber
separated off by a curved radial wall. [Fig 4]

1799 One of Watt?s co-workers, Murdock, adapted Pappenheim?s gear
pump to create a rotary piston steam engine. [Fig 5]

1846 Elijah Galloway built the first rotary piston engine with
inner epicycloid and enveloping outer line. [Fig 6]

1859 Jones, modified Pappenheim?s gear pump and produced a double
rotor with only two teeth per gear. Rootes compressors and pumps
employ this principle. [Fig 7]

1900 Alotham and Franchot designed a vane compressor comprising a
bust rotating inside a cycloidal housing. [Fig 8]

1901 The American, Cooley, lodged a patent for a rotary piston
engine with an internal epicycloid and enveloping outer chamber.
[Fig 9]

1908 The Englishman, Umpleby, transformed Cooley?s steam engine
into an internal combustion engine but experienced problems with
gas tightness. [Fig 10]

1923 A Swedish patent was granted to Wallinder and Skoog in respect
of a true rotary piston thermal engine with toothed meshing,
enveloping interior hypocycloid and internal five pointed rotor
with a 5:6 rotation ratio which could be used as either a two or
four stroke internal combustion engine. [Fig 11]

1938 Sensaud and Lavaud, (the French engineers responsible for the
Traction Avant automatic gearbox which was a failure) applied for a
patent for a rotary piston engine with internally meshing gears in
a hypocycloid housing and a 5:6 reduction ratio. Both Renault and
Citroën, at the instigation of the French Air Ministry provided
backing for this project and a number of engines were built at
Batignolles. Unfortunately the engine failed to live up to
expectations and the project was abandoned. [Fig 12]

1943 The Swiss manufacturer Bernard Maillard built an air
compressor based on a British patent for a rotary piston machine
with a 2:3 ratio and internal hypocycloid surfaced chambers.

Leakage under pressure made it impossible to use this design as a
thermal engine. [Fig 13]

----------------------------------------------------------

Hi!: I'd say that Mr. Jean Claude
Lefeuvre, who invented and built with success a non-Wankel RCE based
in a vane pump style of design,can give you some help in the
problems of sealing, he managed to have his engine working well,
and as he has a little child, being paid for this kind of expert
advise would be good for him, the e-mail address of his business is
lefeuvrepub@sfr.fr o turbineradiale@sfr.fr Hope this is of
some help to you, below please find the link to the YouTube video
about this original Non-Wankel Rotary Combustion Engine by Mr J C
Lefeuvre, there are at least 4 videos about 2 types of the same new
engine installed in motorcycles.
http://www.youtube.com/watch?v=sKrWB3aJeaU

Best regards, salut +

Jose Gros-Aymerich  Madrid, Spain --

Paul.
Thanks for this info.
jd


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