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Brakes on Drive Shaft ?

  1. Dec 27, 2007 #1
    Brakes on Drive Shaft ??

    HI all,

    I am new to this forum. I have a doubt on braking system. Any help in this regard is highly appreciated.

    Why can not we have brake on drive shaft or some point at flywheel ??

    Any discussion in this regard is appreciated. I am hoping to find a solution here.

  2. jcsd
  3. Dec 27, 2007 #2
    what is the problem with the brakes with wheel hub??
  4. Dec 27, 2007 #3

    There is no problem with the brakes on hub. But anyway the wheel hub is rotating by a shaft which in turn rotating with a drive shaft. So a simple arrangement to stop or slowingdown the drive shaft, results the same, thus I can eliminate the brakes on wheel. What are the limitations I have to think like this ??

  5. Dec 27, 2007 #4


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    If you put a brake on a car's drive shaft instead of one on each wheel, then if one wheel was getting traction but the other wasn't getting traction, you'd not be able to slow the car down.
  6. Dec 27, 2007 #5


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    There would be the disadvantage of putting high stresses in the drive shaft or transmission to wheels, leading to increased wear or perhaps failure of the drive shaft, gears, joints or connecting rods between transmission and wheels.

    On a car with two wheel drive - as opposed to 4-wheel - the braking on the drive shaft would affect only two wheels connected to the transmission, and one would still need additional breaking on the other two wheels.

    There is a possibility to use dynamic (regenerative) breaking associated with the drive shaft, either electrically or mechanically.
  7. Dec 27, 2007 #6
    like most other ideas on cars it has been done
    early 60's BRM F-1 racers had a brake on the transaxle
    problems with heat killed the transaxle brake

    a flywheel is not a good place to brake and add heat
    remember brakes work by making heat
    and the flywheel needs to turn or the motor stops
  8. Dec 27, 2007 #7


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    I've only seen one setup where the brake was on the drive shaft, but early Jags and maybe a few other makes had inboard discs that worked on the axle shafts.
    The drive shaft one was actually referred to as a differential brake, because it was attached where the drive shaft entered the banjo. It was on 'X-treme 4x4' (Spike channel), on a rock crawler.
  9. Dec 27, 2007 #8


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    Most drivehafts are made of thinwall tubing, u-joints are designed to transmit power of acceleration, and stopping a fast moving vehicle will in many cases involve far more stress on these two items, than they will endure.
    Many big trucks, and lots of heavy machinery have brakes on drive shafts, but the purpose is only to hold a stationary position.
  10. Dec 27, 2007 #9
    HI all,

    Thanks for the time and discussion. I understand now, the limitations to have a brake system on drive shaft.

    But added to this, suppose if I am thinking of a 4 wheel drive, with a brake arrangement on front / rear transaxle, with a sufficient method to heat dissipation, I must be able to design a brake system right ???

    Can any one help me in providing some information about Dynamic ( Regernerative) braking system ??? Some useful site ??
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