Automatic reciprocating hydraulic circuit?

[treaney]

Hi Folks,

I need an automatic reciprocating hydraulic circuit to operate off my Zetor Crystal's hydraulics. The desired function is to automate the function you would get with a two way spool valve that causes a cylinder to extend and retract. Normally this is done by manually moving the spool valve control lever. I would also like the cycle time and the dwell time i.e. the amount of time the cylinder spends fully extended to be programmable and to have a fast return function.

I will send a six pack of Guinesss to the first person to post an implementable hydraulic circuit diagram to achieve this. Get thinking folks...

Could a newer tractor (Zetor or other) with programmable electro-hydraulics be setup to perform this function?

TomZ
Tom

 

[treaney]

Hi Folks,

I need an automatic reciprocating hydraulic circuit to operate off my Zetor Crystal's hydraulics. The desired function is to automate the function you would get with a two way spool valve that causes a cylinder to extend and retract. Normally this is done by manually moving the spool valve control lever. I would also like the cycle time and the dwell time i.e. the amount of time the cylinder spends fully extended to be programmable and to have a fast return function.

I will send a six pack of Guinesss to the first person to post an implementable hydraulic circuit diagram to achieve this. Get thinking folks...

Could a newer tractor (Zetor or other) with programmable electro-hydraulics be setup to perform this function?

TomZ
Tom

 

[lspringeradelphianet]

Tom - trying to split wood faster, are you? I just use a spool valve that has detents for both directions - it's the easier way to get faster.

But the absolute fastest way to split wood that I have seen is to use the mechcanical kind that has a flywheel and a rack and pinion drive.

 

[lspringeradelphianet]

Tom - trying to split wood faster, are you? I just use a spool valve that has detents for both directions - it's the easier way to get faster.

But the absolute fastest way to split wood that I have seen is to use the mechcanical kind that has a flywheel and a rack and pinion drive.

 

[arctic003]

Hi Tom

Have you thought about using something electro-mechanical to physically move the spool valve lever?

Maybe at its simplest, something like a car wiper motor turning a threaded rod, through a nut attached to the spool valve lever? Then you'd just need a couple of microswitches to signal the movement limit and a 555 timer circuit to set the amount of delay needed at each end... just a suggestion.

003

PS. Plus of course a huge emergency stop button...

 

[arctic003]

Hi Tom

Have you thought about using something electro-mechanical to physically move the spool valve lever?

Maybe at its simplest, something like a car wiper motor turning a threaded rod, through a nut attached to the spool valve lever? Then you'd just need a couple of microswitches to signal the movement limit and a 555 timer circuit to set the amount of delay needed at each end... just a suggestion.

003

PS. Plus of course a huge emergency stop button...

 

[treaney]

Hi Popeye and Arctic,

Thanks for your suggestions!

As my design must be absolutely bulletproof, I'm steering towards using a Micro PLC - probably a Siemens Logo! as the controller which is available for around 100. I will have to use electro-hydraulics which will be expensive however.

The function I want is illustrated by circuit 6[/] on:
http://www.ul.ie/~gordons/martinleary/circuits.htm
Pneumatics is easy - you can exhaust the return to atmosphere - not feasible with hydraulics but this illustrates the functionality I require.

The Micro PLC will allow me to control the dwell time i.e. the amount of time the ram is extended. Big pipes (and possibly a special valve) will permit a fast return.

TomZ
Tom

 

[treaney]

Hi Popeye and Arctic,

Thanks for your suggestions!

As my design must be absolutely bulletproof, I'm steering towards using a Micro PLC - probably a Siemens Logo! as the controller which is available for around 100. I will have to use electro-hydraulics which will be expensive however.

The function I want is illustrated by circuit 6[/] on:
http://www.ul.ie/~gordons/martinleary/circuits.htm
Pneumatics is easy - you can exhaust the return to atmosphere - not feasible with hydraulics but this illustrates the functionality I require.

The Micro PLC will allow me to control the dwell time i.e. the amount of time the ram is extended. Big pipes (and possibly a special valve) will permit a fast return.

TomZ
Tom

 

[arctic003]

Hi Tom

As the system is fairly simple, maybe you don't need a microcontroller to control your dwell time? Wouldn't dedicated timer circuitry (ie the 555 suggestion) be a lot simpler and a thousand times cheaper?

I have used 555s in fairly noisy environments - for example electric fence chargers - with good results.

If you do use a microcontroller there is lots of stuff on the net. I made a PIC programmer a couple of years back and had fun making it do useful things - ok, well, flashing lights and sending "HELLO WORLD" to the serial port of my portable

 

[arctic003]

Hi Tom

As the system is fairly simple, maybe you don't need a microcontroller to control your dwell time? Wouldn't dedicated timer circuitry (ie the 555 suggestion) be a lot simpler and a thousand times cheaper?

I have used 555s in fairly noisy environments - for example electric fence chargers - with good results.

If you do use a microcontroller there is lots of stuff on the net. I made a PIC programmer a couple of years back and had fun making it do useful things - ok, well, flashing lights and sending "HELLO WORLD" to the serial port of my portable

 

[treaney]

Jean-Paul,

I will need a Micro PLC with about 10 digital IO. There are a couple of other cylinders in the machine I am designing.

Re cost - The Simen Logo! starts at 100. You can't get much cheaper than that.

I used the ubiquitous 555 timer a lot about 25 years ago.

When you say PIC - do you mean Programmable Interrupt Controller as in the Intel 8259 PIC with NMI etc.

TomZ
Tom

 

[treaney]

Jean-Paul,

I will need a Micro PLC with about 10 digital IO. There are a couple of other cylinders in the machine I am designing.

Re cost - The Simen Logo! starts at 100. You can't get much cheaper than that.

I used the ubiquitous 555 timer a lot about 25 years ago.

When you say PIC - do you mean Programmable Interrupt Controller as in the Intel 8259 PIC with NMI etc.

TomZ
Tom

 

[arctic003]

<When you say PIC - do you mean Programmable Interrupt
<Controller as in the Intel 8259 PIC with NMI etc.

No, the PIC16C84 Microcontroller IC made by Microchip Inc.

 

[arctic003]

<When you say PIC - do you mean Programmable Interrupt
<Controller as in the Intel 8259 PIC with NMI etc.

No, the PIC16C84 Microcontroller IC made by Microchip Inc.

 

[treaney]

I did a lot of work in the early 1980's with Intel 8 bit micro-controllers - the 8051 family.

The PIC is a more modern version.

TomZ
Tom

 

[treaney]

I did a lot of work in the early 1980's with Intel 8 bit micro-controllers - the 8051 family.

The PIC is a more modern version.

TomZ
Tom

 

[Renze]

Hey hey, you bitfreaks, the 8051 processor was before my time !!
please additional information ??

The oldest i've gamed and wrote essays with, was a 8088 i believe..? In those days Motorola was the biggest concurrent of Intel, and AMD was never heard off...

About your system, you could use a push rod attached to your cylinder. When it is fully extended, it pushes the pushrod and the hydro lever kicks back.

With a different plumbing, and a spring to your cylinder, you can use a spool block with automatic kick-out, like most newer tractors have. When there is max. pressure and no flow (when cylinder is fully extended) it will kick out, and the spring will pull your cylinder back in. So all you do is operate the outgoing stroke, (with a 2/3 valve ??) and it will kick out when the stroke is complete, and the spring will pull it back.

But... If you want to operate more cylinders in the same cycle, a PLC would indeed be better...

By the way, what are you designing ?? an automatic wood chop-to length/splitter combo ?? they already exist, some Finnish companies sell them.

 

[Renze]

Hey hey, you bitfreaks, the 8051 processor was before my time !!
please additional information ??

The oldest i've gamed and wrote essays with, was a 8088 i believe..? In those days Motorola was the biggest concurrent of Intel, and AMD was never heard off...

About your system, you could use a push rod attached to your cylinder. When it is fully extended, it pushes the pushrod and the hydro lever kicks back.

With a different plumbing, and a spring to your cylinder, you can use a spool block with automatic kick-out, like most newer tractors have. When there is max. pressure and no flow (when cylinder is fully extended) it will kick out, and the spring will pull your cylinder back in. So all you do is operate the outgoing stroke, (with a 2/3 valve ??) and it will kick out when the stroke is complete, and the spring will pull it back.

But... If you want to operate more cylinders in the same cycle, a PLC would indeed be better...

By the way, what are you designing ?? an automatic wood chop-to length/splitter combo ?? they already exist, some Finnish companies sell them.

 

[arctic003]

< By the way, what are you designing ?? an automatic wood chop-to
< length/splitter combo ?? they already exist, some Finnish
< companies sell them.

They are really popular at least in this part of Finland, and I guess all over the country.

You feed tree-trunks in at one end, and chopped to length split firewood comes out of the other end on a conveyor belt, straight into your waiting trailer...

http://www.agrimarket.fi/main.cfm?iA=2356

 

[arctic003]

< By the way, what are you designing ?? an automatic wood chop-to
< length/splitter combo ?? they already exist, some Finnish
< companies sell them.

They are really popular at least in this part of Finland, and I guess all over the country.

You feed tree-trunks in at one end, and chopped to length split firewood comes out of the other end on a conveyor belt, straight into your waiting trailer...

http://www.agrimarket.fi/main.cfm?iA=2356

 

[treaney]

RE http://www.agrimarket.fi/main.cfm?iA=2356

Very interesting....it looks like I have a long way to go to get up to the standards of these boys!!!

It's good to see machines like this as it gives you ideas.

TomZ
Tom

 

[treaney]

RE http://www.agrimarket.fi/main.cfm?iA=2356

Very interesting....it looks like I have a long way to go to get up to the standards of these boys!!!

It's good to see machines like this as it gives you ideas.

TomZ
Tom

 

[treaney]

Renze - Intel's 8-bit MCS 51 CHMOS microcontroller family is optimized for control-oriented applications. It was introduced in the early 80's. See http://www.intel.com/design/mcs51/cf_51.htm

The 16 bit 8086 family also came out in the early 80's suceeding the 8085 8 bit processor. BTW I also used the 8085 on Intel multibus SBC (Single Board Computers) on AGV (Automatic Guided Vehicle) projects.

For my hydraulic circuit, I need something that is bombproof. I have one that I will post in the photo gallery.

My latest project is not wood splitting but "Mechanical dewatering by means of hydraulic compression ".

TomZ
Tom

 

[treaney]

Renze - Intel's 8-bit MCS 51 CHMOS microcontroller family is optimized for control-oriented applications. It was introduced in the early 80's. See http://www.intel.com/design/mcs51/cf_51.htm

The 16 bit 8086 family also came out in the early 80's suceeding the 8085 8 bit processor. BTW I also used the 8085 on Intel multibus SBC (Single Board Computers) on AGV (Automatic Guided Vehicle) projects.

For my hydraulic circuit, I need something that is bombproof. I have one that I will post in the photo gallery.

My latest project is not wood splitting but "Mechanical dewatering by means of hydraulic compression ".

TomZ
Tom

 

[Renze]

Hmm.. Mechanical dewatering of what ?? of fire wood ?? or dewatering of farmland, a kind of complicated pump ??

 

[Renze]

Hmm.. Mechanical dewatering of what ?? of fire wood ?? or dewatering of farmland, a kind of complicated pump ??

 

[arctic003]

Tom is planning on saving time in the bath by making a machine to squeeze out his bath-sponge

 

[arctic003]

Tom is planning on saving time in the bath by making a machine to squeeze out his bath-sponge

 

[treaney]

Hmm.. Mechanical dewatering of what ?? of fire wood ?? or dewatering of farmland, a kind of complicated pump ??

Biomass!

BIOMASS: energy from organic matter which has stored sunlight in the form of chemical energy.

Ideally to reduce water content from 80% weight/volume to 30%.

Any ideas anyone?

TomZ
Tom

 

[treaney]

Hmm.. Mechanical dewatering of what ?? of fire wood ?? or dewatering of farmland, a kind of complicated pump ??

Biomass!

BIOMASS: energy from organic matter which has stored sunlight in the form of chemical energy.

Ideally to reduce water content from 80% weight/volume to 30%.

Any ideas anyone?

TomZ
Tom