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Author Topic: Reverse problem on a M-H-B .  (Read 2965 times)

rhavrane

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Re: Reverse problem on a M-H-B .
« Reply #25 on: September 12, 2020, 05:38:30 pm »

Bonjour,
Kbio is unfortunately right, Typhoon has stopped its activities, so only exist Anton and JMC in France now.
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Raphaël
Raphaëlopoulos Steam Lines UnLimited
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southsteyne2

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Re: Reverse problem on a M-H-B .
« Reply #26 on: September 13, 2020, 12:18:36 am »


Hi all is this a type of slip eccentric? I would like to understand how it works perhaps a schematic or closeup image would be great.
Cheers
JohnHi all  my unanswered question was regarding the O ring mechanism as I am familiar with the Cheddar Gemini version as already been discussed in this topic  sorry to have caused any confusion.CheersJohn


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KBIO

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Re: Reverse problem on a M-H-B .
« Reply #27 on: September 13, 2020, 10:47:37 am »

Good morning!
sorry for the poor quality of the video, but I din't redo it as I need 3 Hrs to load 3 min on Utube!
The virus is in the pipe ! >:-o




The principle is easy and smart !To reverse an engine , we need to change the timing by 180 °. The steam entering by the top port  for example, will now enter by the bottom port , making the engine run in the opposite direction.- The eccentric shaft will be driven by the crankshaft via two gears, but not directly.- Both gears have the same diameter. The gear on the crank shaft is mounted solid on it. The gear on the eccentric shafts is left free.- On the eccentric shaft there is a sleeve mounted solid, with a side cut as a half-moon.- On the  eccentric driven gear there is a small pin - The rotation will be transmitted to the eccentric shaft by the pin catching the edge of the half moon.To change the timing by 180° we have to change the side of the half moon caught by the pin. This means that we must rotate the half moon by 180°. This will be done by friction with a special lever acting on the O’ring installed on the sleeve of the half moon. Let the outside diameter of the O’rin be 9mm which gives us a diameter roughly of 28mm. To rotate it by 180° we need to impose a movement of 14mm.This is achieve via a side commanding plate rotating free around the crankshaft with a friction part (arc) acting on the O’ring. And therefore the length of the friction arc must be 14mm. ==> exactly 1/2 of the half moon nut.Once the rotation of 180° has been achieved, the shape of the commanding plate and its rotation must be such that there is no more contact and friction with the O’ring. A bit of geometry and trigonometry (depending of the diameter of the friction arc) will give you the needed rotation of the commanding lever (around 120°).And of course the change of the timing must be done while the engine is stopped. Otherwise, the O’ring won’t last very long!!
The slides valves adjustment is exactly as  conventional ones taking into account that the rotation has to stick the command lever in the same direction.
 Exactly what we need to make the half moon rotating 180° and displace the sliding sleeves from top to bottom.The engine runs in the other direction.
Obviously, the engine has to be stopped to rotate the O'ring.


Here is a video in French but with the above comments , the Forum's steamer are smart enough to visualize the operation.
Sorry for the quality! I wish Keith Appelton would do it for me!! It would be more professional.


https://youtu.be/kGuSinQ2gu0

Best regards.
Yves.
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