brake-holding-clamping methods for linear motion

[tygerdawg]

I'm designing a positioning device using

=> end-supported linear rails like Thomson products
=> integrated rail/supports with a hand-cranked ballscrew

I want to move it a location, then clamp it in place.

Can anyone suggest methods to do this or products available so that I don't have to re-invent the wheel?

Thx

Email is a stealth email to minimize spam. Contact me & I'll get back in touch with you.

TygerDawg

 

[Barry1961]

I have seen bronze tip screws and clamp collars used with good results. Also making a custom split clamp collar out of a aluminum bar works well. If you make your own split type clamp out of a bar you can extend the clamp screw/handle out far enough that it is very easy to use.

Barry1961

 

[CouplingKing]

A couple of years ago I looked at designing a holdback system for vertical ballscrews for use on the vetical axis of machine tools. Other projects superceeded it and it went no further.

Essentially there are very few options for ballscrew/linear motion braking/holding. The most popular system appears to be a bulky hydraulic clamp arrangement. I must admit I have never seen one and only been told about them.

One option is to use a brake or clutch on the ball screw. If you use a spring applied brake then simply energise to release and allow movement. Warner, KEB, Lenze, Mayr etc all offer this sort of kit.

Manual systems like the one suggested by Barry1961 work well if you can get access to the machine to fix them and you don't want to move them often. If more flexibility is required you will almost certainly have to sort it out yourself.

Good luck

CK

 

[Iskit4iam]

The simplest thing you could do is not use a ballscrew. You need to brake a ballscrew because their high efficiency levels allow back driving. Eliminate the low friction of the ball and the screw, except at very high helix angles, will self lock.

When I built ballscrew actuators for Warner Electric we used a wrap spring brake to prevent backdriving but our acme screw actuators had no brake.

 

[sreid]

We use a metal blade attached to the saddle in the direction of motion. An air operated pincher then grabs the blade to hold the axis in place.

 

[EnglishMuffin]

If you don't mind using profiled linear guideways other than Thomson, try Zimmer clamping systems

http://www.techspecinc.com/Products/Zimmer.htm

They look as if they might even do something for Thomson linear shafting as well - check with them.