Suggest a suitable Motor

[koushik123]

I'm in the process of building a shock absorber dynamometer.I have planned to use a 2 HP motor with a max RPM of 1750 for this.
But the required working range is from 20 RPM-200 RPM
1.Is it possible to achieve this using a VFD??
2.And kindly guide me whether to choose an AC or DC drive?? and
3.How to determine the torque required to overcome the force of the shock absorber
I'm completely new to this and I want to learn.
Anticipating useful answers.

 

[koushik123]

The weight of the shock absorber that will be tested in this machine ranges upto 13 KG

 

[waross]

Try a gearhead motor with an 8.75:1 reduction. The torque required will depend on the shock absorber and the speed at which it is operated. You will have to figure that out yourself.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[mikekilroy]

How did you arrive at "2hp?" if you do not know the torque required?

For those of us who do not know exactly what a shock absorber tester is, how about a brief description?

Some questions I think of:

1) I assume your 20-200rpm means you will be pushing the linear shock rod up and down at a rate of 20 - 200 times per minute?
2) Is it critical how the motion profile looks? Triangular motion? trap? sine?
3) Any accuracy requirements during the motion?
4) Do you need to know exact position of shock rod at all times for plots or other reasons?
5) Will you have a torque transducer or force monitor thing on it to record each stroke's force? speed? position?
6) how do you have to control it? Just turn on and a speed pot? Motion controller? PLC?
7) It is of a size that can run on 120v? 220v? 460? 1ph? 3ph? All of the above?
8) What is the budget? You can do lowest end cheap gearmotor that might last 6 months and cheap vfd for maybe $ 2000 total, all the way up to servo system direct drive for say $ 5000.00 or more.

http://www.KilroyWasHere<dot>com

 

[mikekilroy]

Shock testing sounds pretty simple, but I have an employee who ran one of GM Delphi shock absorber test/design labs for 20+ years. They would send him all around the world to just ride in the mfgr's cars - he could tell them by the seat of his pants what was wrong with their particular designs. Listening to him talk about those dumb little things is amazing - I never knew there was so much design in them.

http://www.KilroyWasHere<dot>com