Hi Paul,

          Maybe in a few words I can clarify the gear concept. You've
    said this
    in
          different words before so if I'm too far off base please edit.

          The gears inside the rotary are a means of  "timing"  the
    position of
          the rotor. Very much akin to the way   "timing"  gears ( or
    chains or
          cog belts )  "Time"  the position of the CAMshaft in an auto
          engine.  *** POWER is not transmitted in either case, only the
    exact
          POSITION is determined.***  This  "timing"  is necessary to
    put the
          piston engine valves in the proper place at the proper time,
    in the
          rotary this  "timing"  is necessary to put the rotor in the proper
          place
          at the proper time.

          Concept any clearer or did I muddy the waters even more.
          Dave

          Excellent. Much better than I could have put it. Very concise.

          Paul Lamar ...No rotor no motor.

    Yes..  That is very good.  Can I help with the language?

    The gears inside the rotary are a means of  "timing"  the position and
    orientation of the rotor.  This is very much akin to the way
    "timing"  gears ( or chains or cog belts )  "time"  the position of the
    CAMshaft in a piston engine.  *** POWER is not transmitted in either
    case, only the exact POSITION is determined.***  This  "timing"  is
    necessary to put the piston engine valves in the proper place at the
    proper time.  In the rotary this "timing" is necessary to put the rotor
    in the proper place and orientation at the proper time.


    Matt-


    I'll still act dense here.

    It seems that "timing" (except ignition timing, which can be handled
    in many
    ways) is a function of the placement and shape of the ports. Since
    the ports
    are open and closed by the position of the rotor and the rotor will
    go as
    fast as its load, design, and inputs allow it, where is the "timing"
    issue?

    Ports will be open whenever the rotor isn't blocking them, unlike
    the valves
    in a piston engine, which will open when the camshaft says. If a cam
    belt or
    chain slips a tooth, valve timing will change; what can change in a
    rotary?

    Tim Kern

    Nothing. If it slips a tooth it will jam. Extremely rare occurrence.
    Far less of an occurrence than a cam changing timing due to worn
    teeth. Engine can be over hauled several times without replacing
    the static or rotor gear.

    BTW p-ports never close. As the chambers comes by the ports two
    chambers can be open at the same time. The rotary is closer to a
    continuous combustion engine (jet) than it is to a intermittent
    combustion (piston) engine.

    Paul Lamar ...No rotor no motor.


Maybe I can try again...  Requoting:

The gears inside the rotary are a means of  "timing"  the position and
orientation of the rotor.  This is very much akin to the way
"timing"  gears ( or chains or cog belts )  "time"  the position of the
CAMshaft in a piston engine.  *** POWER is not transmitted in either
case, only the exact POSITION is determined.***  This  "timing"  is
necessary to put the piston engine valves in the proper place at the
proper time.  In the rotary this "timing" is necessary to put the rotor
in the proper place and orientation at the proper time.

 >From dictionary.com <http://dictionary.com>: Timing: 1.the system of
those sequential relations that any event has to any other, as past,
present, or future; indefinite and continuous duration regarded as that
in which events succeed one another.

"Timing" in this context is not about seconds, minutes, or hours so much
as it is about the precise order in which things happen.  "Timing" an
engine is about degrees of rotation of some shaft in the engine,
regardless of RPM.  This means that "timing" is not about "time," but
about the order of operation.

So, rewriting the above...

The gears inside the rotary are a means of  controlling the position and
orientation of the rotor within the housing.  This is very much akin to
the way timing gears ( or chains or cog belts )  "time"  the position of
the CAMshaft in a piston engine.  *** POWER is not transmitted in either
case, only the exact POSITION and ORIENTATION of various pieces are
determined.***  This  "timing"  is necessary to put the piston engine
valves in the proper place at the proper time.  In the rotary this
"timing" is necessary to put the rotor in the proper place and
orientation at the proper time.  The gears force the rotor to be
oriented correctly at any given position of the e-shaft in order for the
combustion cycles to take place.


Other things to consider:

Without the correct gearing, the rotor would be free to rotate on the
e-shaft.  This would allow (among other things), depending on how the
rotor was oriented, gases to travel from above one rotor face to an
adjacent face by passing around the end of the apex of the rotor.

Many piston engines will "jam" if the cam slips a tooth - a valve will
contact a piston.


Regards,

Matt-

If I may add a little comment as well:
The gearing provides proper "orientation" of the piston. Piston
"position" is provided by the Eccentric shaft.

The above text should read:
The gears inside the rotary are a means of  controlling the   [omitted:
'position and']
orientation of the rotor within the housing. Piston positioning is
provided by the eccentric. This is very much akin to ...

The last sentence spells it out correctly as only 'orientation ' is
addressed.
I also agree that this is a very good explanation.


The last paragraph
"Other things to consider"
is not really correct.

The piston will jam immediately if the orientation of the eccentric
shaft and the matching orientation of the piston is not exactly as
needed. The piston can not be turned on the eccentric shaft assuming no
gears are present.

That actually was a contributing factor for the chatter marks of the
early days when orientation was not as precise and the surface too weak
allowing apex seal indentations into the trochoide to happen.

Any deviation from the exactly needed position will force one apex seal
off the trochoide and another apex seal into the surface of the
trochoide depending on the present orientation of the piston. Since
entry into the surface is not possible, lifting off of another apex seal
is also not possible.

Rolf


Write it all out for me Rolf :)