Self locking in Compound spur gear train 1

[thought2007]

Hello,

I were going through Electromechanical actuator document which is driven by DC Motor with Compound spur gear train.

But the system demands self locking feature after actuator reach 90deg rotation.My Question is there any possibilities of self locking with compound spur gear train (actuator doesnt have worm gear mesh ).

Regards
John

 

[MikeHalloran]

No.

There are other ways to lock an actuator, but spur gears alone won't do it.



Mike Halloran
Pembroke Pines, FL, USA

 

[engrenage]

Hello,
Maybe there is a solution. If you can use helicals gears there are (very!) specials gears with only one tooth in the pinion.
The axes are paralels and the gear train is self-locking.
You can show some explainations and the patent at this link:

http://v3.espacenet.com/publication...T=D&date=20100114&CC=US&NR=2010005915A1&KC=A1

Regards

 

[drawoh]

thought2007,

Be careful backdriving spur gear trains. I have analyzed some small gearmotors and have worked out that you can accelerate the gearhead output shaft fast enough to overstress the motor shaft. Your armature inertia may be very small, but it is multipied by the square of the gear ratio.

Spur gears do not lock the way high ratio worm gears do. A high ratio spur gear box may appear to be locked because the torque needed to accelerate your armature is more than you can exert by gripping the gearhead shaft with your fingers.

Your final assembly may provide the additional leverage needed to make this physically easy. The problem will not be obvious to whoever is installing it or playing with it.

JHG

 

[thought2007]

Hi Everyone,

Thanks for suggestions!!

Indeed I started working by adopting worm gears to lock

Thanks once again

John

 

[israelkk]

If the system vibrates the worm gear will not lock.