Bungy and Surgical tubing

[boomergeek]

Originally Posted by boomergeek

Actually I'm worried that the 20 inches per second piston speed has been claimed (by multiple persons posting to CD) to have been given from Bimba Customer Support representatives.
As far as I know, no one with any expertise has stated equivocally under which conditions that it is SAFE to ignore 20 IPS guide on piston speed.

I typically choose to considered it likely to be deemed unsafe by thoughtful robot inspectors unless an expert vouches for the SAFETY of the configuration.

If leaving a piston attached to a "bow" when shooting an arrow is an engineering acceptable use of pneumatic piston, will someone with expertise in the failure modes of actuators please confirm?

My e-mail to Bimba:
We are designing use of Bimba 1.5 in bore and 8" stroke cylinders in a FIRST robotics application.
The application has robust external stops to prevent the piston from reaching both of the end-caps.
The application calls for the piston to reach 80 inches per second (IPS) for a small portion of its non-pneumatically powered return stroke.

Is an unpowered piston speed of 80 IPS allowed by Bimba design rules?

If this high speed does not conform to Bimba design rules, is the non-conformance a safety issue or a warranty/wear issue?

Your prompt attention would be much appreciated....

(within 12 hours( ) they sent me the following response...)

80 in/sec is not out of the question as far as speed, but you will not be able to bottom out the cylinder. It needs to hit rigid hard stops to withstand this speed given standard design specs. I am assuming this isn’t a case where it will be oscillating at that speed for long periods of time. If so there would be a worry about heat buildup. Instead I assume this is a load or retract move the cylinder is making. Given that scenario, you should be ok.

C____ W_____
Technical Center Engineer






So now we have expert opinion that piston speed is primarily an end-cap rule.


I guess we will have to slow down our firing rate on our kicker to less than 10 shots a second so we don't need to worry about heat.