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Belt Drive theory and basic knowledge ... for a practical example

HP is not measured? ? ? ? ? ? ?

In WHAT universe?



On paper it is simple math ,approximately a 4 to 1 reduction @ 2100rpm. On paper The HP will be the same. Actual output will make the paper calc's less because of transmission losses. Remember HP is a work calculation , it is not measured. Torque and rpm are measured and then HP is calculated. So your statement "at whatever speed" doesn't make sense, the speed will be exactly what the reduction ratio is(that doesn't change). But to have that exact out put rpm you would have to increase the input torque to cover the transmission losses which will increase HP required.
You can work the problem two ways ,You only have so much HP available then your out put is predetermined,or you need so much HP then your input has to be variable. Make sense?
So in your example you would have to go to 5 to one or more to cover the losses but your output rpm decreases.




As I said before look into Gates Polychain belts. They will answer most of your questions about HP per pound and efficiency . The power transfer of Polychains is among the highest of all belt drives.
 
Easily done on a prototype aircraft. Rubber, neoprene..ect belts satisfy a great deal of material deformation when transmitting power. Also when using them in a perpendicular drive like a MXL XL L..ect application base material fatigues. One of the things that have been done to great success has been nylon, kevlar and the like keeping the band intact. However due to material deformation and small thermal changes at the molecular level this type of power transferral requires a consumable and that is the softest most pliable component or weak link which would be the rubber compound. Due to this factor belts are typically not used in applications where life and death are encumbant on the mfg process. But If you were a risk taker this would be par for the course.
 
HP is not measured? ? ? ? ? ? ?

In WHAT universe?
If you apply a 100lb force on a lever attached to an non moving shaft how much HP is developed? I'll help you out NONE.Now revolve the shaft with the same force at any steady revolution and then HP is easly calculated. No different than a 10k lb rock sitting on the ground , no hp is developed. Roll it a distance in a given time then you can calculate HP.
What do you think a dynometer measures?
 
Ultra lite builder sez......if the motor cuts ,or the belt breaks .....I will glide to a safe landing...........fact sez two more utralite flyers killed in crashes last weekend.
 
Ultra lite builder sez......if the motor cuts ,or the belt breaks .....I will glide to a safe landing...........fact sez two more utralite flyers killed in crashes last weekend.
they all end up on the ground, one way or another
 
Every ultralite crash death costs taxpayers around $1million .......DCA crash investigation team & report ,police investigation and report ,and a coroners inquest.
 








 
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