pantograph sizing

[AlberTz]

Hello, everyone.
Would someone advise me how to study the design of a hydraulic pantograph?
I tell you what I would do:
- maximum thrust calculation which must develop the actuator
- binding reactions of all hinges
- choice of bearings
- study of stinging moments, cutting, axial efforts
- geometry dimensioning of various pantograph arms
- dimensional connection pins of the various details

Something missing?
There is only one problem: I'm not convinced of the calculation of binding reactions. . .supposing of having one as in photo, but with a "x" in less (the upper one) the rest is similar (including the disposition of the piston), can I define a static condition (vertical component of the piston force equal to the load) studying only half the pantograph?

Maybe I'm complicating my life, if someone could give me a tip, I'd be grateful
Unfortunately, I find nothing like this... .

Thank you, hello!

 

[gerod]

Let's do this:
first you show up (read the rules) and then we answer.
Okay?

 

[AlberTz]

Okay!
If I understand correctly, I have to introduce myself. .
I graduated in automation engineering, and work for a robotic prototype company.
I am following a commission on a small forklift, and I have to dimensional all the mechanical structure.
I have some ideas x my head, but I just wanted to have confirmation (because I haven't had many mechanical design opportunities yet, after school). . .
Thank you!

 

[Fulvio Romano]

but the platform raises people?
Is it better to take a look at the rules before jumping into the accounts like a dog on the bone?

 

[AlberTz]

Does the platform raise people? ni...in the sense that it is at first a no but could soon be a yes.
If there are relative rules, would you tell me where to take them? so I can, rightly, make a healthy idea....

 

[pollo]

First, the machine directive (d.lgs.17/2010)

 

[AlberTz]

Great!
Thank you!
while I got a couple of ideas to start smoothly (at least x do not take clamorous chants).
other question: for the pin that makes from cart (what slides horizontalmte x generate the lift), does it make sense to study it as the other?
I better explain: when I choose your bearing, knowing that it has to roll, can I put it directly in contact with the seat of the asola, or better to put it a protection rump? As a bearing I thought one roller... .

 

[gerod]

Does the platform raise people? ni...in the sense that it is at first a no but could soon be a yes.
If there are relative rules, would you tell me where to take them? so I can, rightly, make a healthy idea....

As suggested, I would read the machine directive well and think immediately of that.
the approach to designing high working platforms (ple) to raise people is different from that for a simple platform raises materials.
are machines attached iv ergo you must follow a particular certification iter that, often (but not always, you can choose), requires verification of a notified organism and, I can assure you, it is not a walk!
If I were you, I would take two pigeons with a fava. make a unique project and, at the max, remove what is not required by the rules in the case of lifting goods.
the reference standard (type code c) is en 280.
It's a big mess.
Hi.

 

[AlberTz]

I would say it's a good advice!

 

[gerod]

I would say it's a good advice!

to whom do I write the bill?
:biggrin:

 

[AlberTz]

Maybe first make sure that I don't damage :-d

 

[Fulvio Romano]

If I were you, I would take two pigeons with a fava. make a unique project and, at the max, remove what is not required by the rules in the case of lifting goods.
the reference standard (type code c) is en 280.
It's a big mess.
Hi.

perhaps there is a way to take even bigger pigeons without the use of beans.. .
there are some companies that design, build and sell forklifts. Because it doesn't make any sense to get into the house something like this "to save" because it would cost ten times so much, explain to me what is the purpose of reinventing hot water daily?

Do I miss anything?

I understand that engineering degree is a good thing, but if I have a dark room I don't go out of joule law, I'm going to buy a light bulb.

 

[AlberTz]

true, but first I have to tell my supplier what I need, and if I am as precise as possible it would be better. cmq, being my very small sized pantograph, I don't think it exists on the market. I don't even think I can get some patterns, and then I'm gonna scale. .

 

[pollo]

... since it doesn't make any sense to get into the house something like this "to save" because it would cost ten times so much, you explain to me what the purpose of reinventing hot water daily? . . .

the reason is always the usual: in a country of 60 million technical commissioners of the various nationals, companies think they can do everything within them. the signature of an engineer is enough to regularize.
At the same time, if for civil constructions it is foreseen (more or less) who can do what (geometers, building experts, engineers, etc.), for the machines also the slippers can assume the responsibility of constructor (signing the declaration of conformity) and, unless special cases, there is no need for an expert to the project.
notified bodies which then certify the machine (obligators only for those of a restricted list) are subject to market laws and therefore if I pay them, they certify: seldom the ministerial authorization to NGOs is withdrawn by manifest incapacity, but generally because they violate self-regulation codes.
then proceed to build ple in the house, crane from the slippers, saws to tape from the carpenters, etc.
ps: it is not that then, going to the builder you are more quiet, so much so worth.

 

[pollo]

... but first I have to tell my supplier what I need, and if I'm as precise as possible it would be better. cmq, being my very small sized pantograph, I don't think it exists on the market. I don't even think I can get some patterns, and then I'm gonna scale. .

cvd :frown:

 

[AlberTz]

cvd :frown:

but my client already makes systems like I'm studying. to us asks "only" an improvement, to automate the system.
Before doing unconformed things or unsafe structures, I thought I would deepen my skills not only from a purely mechanical point of view. therefore compliance, regulations, etc. etc.
If then I have the opportunity to find a product already ready, according to my needs, I can already use it. but if I didn't find it, tell them they design according to my specifications, I have to move by "personal" ways.

in all this I say "think", simply because I am not an engineer with 30 years of experience, but an engineer with first arms, and even if I am technical in automation and mechanical expert, and some stupid design I made it at school, the job is a very different world. So I do what my mechanics teacher said:

"when designed, lead feet and cast iron panties"

:smile:

 

[lelepanz]

perhaps there is a way to take even bigger pigeons without the use of beans.. .
there are some companies that design, build and sell forklifts. Because it doesn't make any sense to get into the house something like this "to save" because it would cost ten times so much, explain to me what is the purpose of reinventing hot water daily?

Do I miss anything?

I understand that engineering degree is a good thing, but if I have a dark room I don't go out of joule law, I'm going to buy a light bulb.

we did it at first.
we made a platform for lifting goods of little value and little flow.
made design (or better .... and I am not ashamed to say ... copied from a car already made) ... and to save a 100 €. and to save those 100 € by car we had to make 5 or 10 (I don't remember). and maybe keep the rest in the house for two years.
the assembly was made by us... and by genes that in life has done anything else.
finished the first series ... we decided radically to buy this thing back from the catalog that we found occasionally inside the mailbox.
:
all the world is country....

 

[pollo]

... we decided radically to buy this thing back from the catalog that we found occasionally inside the mailbox... .

which is equivalent to buying on madeinchina.it: In view of the fact that there and the statements of the builders are a presumption of conformity, not a certainty. the user employer remains always responsible for what he delivers to his employees

 

[Fulvio Romano]

we did it at first.
we made a platform for lifting goods of little value and little flow.
made design (or better .... and I am not ashamed to say ... copied from a car already made) ... and to save a 100 €. and to save those 100 € by car we had to make 5 or 10 (I don't remember). and maybe keep the rest in the house for two years.
the assembly was made by us... and by genes that in life has done anything else.
finished the first series ... we decided radically to buy this thing back from the catalog that we found occasionally inside the mailbox.
:
all the world is country....

good, I recommend, write and shout out loudly these things, so as to avoid others falling into the same mistake.

Unfortunately, as many times written in this forum, the big flaw of Italian universities is that they teach you how to calculate bullions creep, but they forget to tell you that they are not to be drawn but chosen to catalog. . .

 

[gerod]

I answer now to all:
by lightning: it is not true that the ple cost you less if made in the house. I have designed 3 for a client with iter and type examination. It doesn't cost you much more than other manufacturers, but you do it as you want and I can assure you that, even if built cars, they are beautiful robust. the influence of the cost is minimal.
we can also discuss price.

for chicken:

notified bodies which then certify the machine (obligators only for those of a restricted list) are subject to market laws and therefore if I pay them, they certify: seldom the ministerial authorization to NGOs is withdrawn by manifest incapacity, but generally because they violate self-regulation codes.

as said, it will also be true but the choice of the on is voluntary! You can also choose not to do type examination but to follow a standard of type c and ... I refer you to the reading of the directive!

I'll stop right here.
Hi.