Throttle levers rotational speed control.

[mirrage]

Greetings!


I design a non-motorized throttle quadrant and I have stumbled upon a serious
issue.
I want the throttle levers to move in a controlled manner and only after a specific
amount of force applied to them.
That means their rotational speed should be restricted somehow.

And hear comes the question...
Could a slip clutch be utilized to achieve that level of control over the lever's rotational
speed?

If not how should I approach that problem?


Thank you all in advance!

[Trevor Hale]

That's how many guys do it, they use a clutch system that offers some resistance.  Also, should you ever decide to motorize them it will allow you to take control of the throttle even with the servos engaged.

Trev

[mirrage]

Well...There is no need to motorize it since it's a Dash 8 throttle quadrant.

I have never before use slip clutches. In fact, I didn't know they existed until
a few days ago so I didn't know they could be used without a motor.

Thanks for the answer.

[FredK]

Even though your TQ is non-motorized you could still attach high torque DC gear motors or servo motors.  A servo motor could be the easiest option to implement.  Such will give you a nice solid resistance feel to your levers.  No need to electrify, etc.

Fred K

[mirrage]

No need to electrify?

You mean just put them in and connect the levers on them
and they will provide enough friction for the levers to move
in a steady/controlled manner?

[FredK]

No need to electrify?

You mean just put them in and connect the levers on them
and they will provide enough friction for the levers to move
in a steady/controlled manner?

Yes...exactly that....no wiring or electrification.  High torque ones (low rpm) will work the best.

Many years ago I built my first 737 throttle using a Simparts kit.  The design of it was very basic....essentially a lever arm connected to a servo motor.  Without the servo motors the throttle levers were very loose and floppy and would not even stay positioned.  Once I mechanically connected the servo motors the levers had a reasonably good feel to them when operated in manual mode (that is, no motor engaged).  No slip clutches or other means of providing friction resistance were used.

Likewise when I did my home conversion of my real 737 throttle the DC gear drive motors also help provide a solid manual motion feel...more so from that than the slip clutches.

This approach will provide you the added benefit of converting to motorization in the future since your motors are already installed.  That is, you could later add an electronic interface and do the software programming.

Fred K

[mirrage]

Sounds very interesting!

Got an eye on high torque servo motors and found a few interesting
videos online too.

There are two types out there one is like a tube and is quite long
around 9-10cm (3,2" to 4") and the other looks like a box and is
enclosed in a plastic case.
How were yours look like and what were their specs?
I don't know what to look for.


Found some information about the DC motors and servos you use
in an older post of yours here...
http://www.cockpitbuilders.com/community/index.php?topic=3278.msg26641#msg26641