Author Topic: Press controls  (Read 2748 times)

Offline PK

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Press controls
« on: June 04, 2016, 01:28:42 AM »
OK, so it only took me two weeks longer than I thought it would to get the project to this stage. But we're here at last..

I've built a little hydraulic press for home.
Of note, I used one of these little units for the muscle: http://www.ebay.com.au/itm/331810274325?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
It has 600mm of stroke, an air motor on the back and is good for 8t.  I invite you to convert the price (which includes shipping) to your local currency. It's an absolute bargain!

So I have all the heavy bits fabricated and working. Now I'm moving to the controls. What I want is a lever control for raise and lower.
 
The lever bit is easy, I have a 5/3 way lever valve.

The press bit is easy, just use said valve to supply air to the motor (might have to be via a pilot operated valve, this thing uses a bit of air).

It's the release bit that has me scratching my head.  I could use a rotary actuator. But the mounting brackets would be a bit of a pain in the arse because the little drain valve is at an angle .I'd prefer to use a ram and control horn, but the same applies. I'd really rather not strip the thing and add a separate valve...

Anyone got any suggestions?

PK

RobWilson

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Re: Press controls
« Reply #1 on: June 04, 2016, 04:02:23 AM »
Hi there PK ,thats a  mighty fine lookin press  :thumbup:  nice job  :clap: :clap:

As to your release problem it all depends on how far you want to hack the cylinder /pump unit .

I came up with this solution , minimal  :proj: required 



Replacing the bleed down screw with a machined up fitting  that matched the screw nose angle ,drilled through and the other end machined to what ever flavoured hydraulic fitting you prefer , BSP, JIC  etc. 

Then pipped back into the oil fill hole further up the cylinder .


Hope photo is clear , I am suffering from one all mighty hangover   this morning  .  :Doh:



Rob 

Offline RussellT

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Re: Press controls
« Reply #2 on: June 04, 2016, 04:14:04 AM »
If I've understood this correctly the screw just releases the fluid internally to let the jack come down.

How far does it need turning - if it's less than half a turn could you use a lever and air cylinder?

Or to simplify mounting how about a flexible coupling to your rotary actuator - or even just an adaptor sliding over the pins sticking out of the screw.

Russell
Common sense is unfortunately not as common as its name suggests.

Offline PK

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Re: Press controls
« Reply #3 on: June 04, 2016, 04:33:27 AM »

I came up with this solution , minimal  :proj: required 
I like it. It's fairly simple and, as you say, it really just one part.. I'll put that up on the top of the list for now..

Quote
Hope photo is clear , I am suffering from one all mighty hangover   this morning  .  :Doh:
:-) That'll teach you to stop drinking!
PK

Offline PK

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Re: Press controls
« Reply #4 on: June 04, 2016, 04:36:53 AM »
If I've understood this correctly the screw just releases the fluid internally to let the jack come down.
Yep.

Quote
How far does it need turning - if it's less than half a turn could you use a lever and air cylinder?
Half a turn does it. The problem, as I see it is that it doesn't rotate on a convenient plane. When I add a few hundred mm of ram to the picture, bits and brackets are hanging out in inconvenient places..
Quote
Or to simplify mounting how about a flexible coupling to your rotary actuator - or even just an adaptor sliding over the pins sticking out of the screw.
Yeah, I thought about a universal joint.. Might be the go...