Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: svejkovat on May 26, 2009, 01:05:50 PM

Title: Please help me find a manual clutch!!
Post by: svejkovat on May 26, 2009, 01:05:50 PM
I can't believe this does not exist.
I'm linking a 35cc Honda 4 cycle to a mountainbike crankset and searching for a manual clutch to
place on the output shaft of a planetary gearbox speed reduction.  Output shaft rpm not exceeding 300rpm
and 40 ft lbs torque.   

I've called a few dozen clutch and sprocket suppliers/manufacturers and am almost finally
convinced that it is impossible to find a sprocket with built in manual clutch in order to
engage and disengage the sprocket/chain drive.

There is no other way to integrate the motor, isolate the motor and motor speed reduction from
pedal power (pedaling while the motor is off)  while still maintaining the ability to pedal-start it.   

Please, please, please tell me there is such a clutch out there.
Title: Re: Please help me find a manual clutch!!
Post by: Asellith on May 28, 2009, 12:29:57 PM
Not sure where we got it but I remember my dad converting a tractor into a go-cart years ago. We used what was called a centrifugal clutch.

Something like this http://www.gokartsupply.com/clutches.htm (http://www.gokartsupply.com/clutches.htm) The concept is that you adjust the clutch to take off when it reaches a certain rpm. So when the motor is idling the clutch is disengaged and when you rev the motor it automatically engages and stays engaged till the rpms drop again.

Hope that helps