Push-pull cable actuation
Push-pull cable actuation
(OP)
Greetings Eng-tips!
I'm looking for Push pull cable, similar to throttle cable, but for a larger application (perhaps 200lbs or so, max 11' distance, roughly 4" push/pull). But this is the easy part.. the more difficult part is that we need the parts to be crimped and fitted in our shop. Most off-the-shelf bits are pre-crimped on the ends.
Can anyone suggest a source for something like this?
I'm looking for Push pull cable, similar to throttle cable, but for a larger application (perhaps 200lbs or so, max 11' distance, roughly 4" push/pull). But this is the easy part.. the more difficult part is that we need the parts to be crimped and fitted in our shop. Most off-the-shelf bits are pre-crimped on the ends.
Can anyone suggest a source for something like this?





RE: Push-pull cable actuation
else just buy some wire and some reasonably rigid tube (to support the cable) ... no ??
RE: Push-pull cable actuation
RE: Push-pull cable actuation
We have a deflection in a frame, it was to be expected. We've tried a semi-rigid linkage (chain and tube) and the deflection makes it an issue. Thus the idea to use something flexible.
RE: Push-pull cable actuation
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RE: Push-pull cable actuation
FWIW, there is a lot of "lost motion" in push-pull cables, and a tendency to have the friction force increase over time. If I was to do it again, I would go with all-tension cables (e.g. aircraft controls). Not that I would ever do it again - prefer hydraulics.
RE: Push-pull cable actuation
Just need to be careful of it's load and travel distance, can't get too crazy.
RE: Push-pull cable actuation
Have you considered linear chain push-pull actuation devices?
ex:
h
RE: Push-pull cable actuation
We've used linear chain in the past, but it doesn't fit in this application I don't think. Ultimately this is a straight up linkage, the twist is that it needs to be designed to accommodate a large deflection in it's main frame and not jam up.
RE: Push-pull cable actuation
Do at least look at the Tuthill designs. They use an overwrap on the center cable, both to provide more compressive strength, and to keep a smoother surface in contact with the outer guide sheath to minimize wear and friction.
The problem is that the overwrap needs to be very carefully removed before crimping fittings in place, and special crimp fittings made that cover the overwrap "tag end" to keep it from unravelling. Thus, they limit who can do the work.
RE: Push-pull cable actuation
We're going to bulkhead the connectors to get to the length we need. I think I can package this well. Still need to transfer motion from rotatory, but that shouldn't be difficult.