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manlifter

manlifter

manlifter

(OP)
we have a manlifter in our company but we are confuse why is it the front wheel is bigger than the rear wheel. and the rear wheel are double tire. we want to know what is the possible reason why the design is like this?

RE: manlifter

Is the lift powerdriven?

If so the dual wheel is probably for traction.

The large wheel might be for getting over an uneven floor.

RE: manlifter

Post a photo, that might help

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>

RE: manlifter

Which wheels are steering?  

RE: manlifter

Just a guess without seeing it, but a higher front axle would increase the effectiveness of the counter-balance weight thereby resisting tip-over.  (Weight being below the balance-horizon)

RE: manlifter

Before I get inundated with rebuttals, let me clarify that it would be only a slight increase.  That being said, in a world where field personnel continually over step the safety specifications of the equipment they are working with, that slight edge may make the difference in someone's life.  

After some more thought on the matter, I'd be inclined to agree with unclesyd's conclusion that it is probably to give it drive-advantage.

RE: manlifter

Or it could be something entirely more practical.  For example, if the drive is hydraulic hub motors the wheels might be sized to accommodate the necessary size motors.

A picture would be useful.

RE: manlifter

(OP)
thak you very much for your commments, by the way it is a front wheel drive and attached to this is a picture of the manlift.  

RE: manlifter

Ah.  A tatty looking conversion.

I think the story here is that the large front wheels are the Nissan OEM size.

The back wheels may well be doubled up simply because that's how the chassis was before the bodybuilders got to it (it's not unusual to see doubled rear wheels on a van - it allows the thing to carry a greater load).

I suspect part of the bodybuilders' new top hamper has intruded into the original wheel arch space so they've had to fit smaller rear wheels in attempt to restore some of the clearance.

A.

RE: manlifter

I'll have to agree with zeusfaber.
Whoever did the conversion probably found it was cheaper to get the smaller double tires in than to try to fit the bigger ones. Plus those yo-yo's in the back can probably hold more weight than the originals.
Is that thing even road-legal?

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>

RE: manlifter

Wheel size have little to do with stability of your "cherry picker" as it is outfitted with outriggers which must always be fully extended when using the bucket.
The wide drive wheels are obviously to take the extra load from the boom, bucket and hydraulic drive. As far as the front wheel it appears to make the truck slightly unleveled--definitely a Rube-Goldberg contraption during the retrofitting.

RE: manlifter

My apologies.  I was under the impression that we were discussing a machine that was designed.   This looks like a homemade rig.  This is a montage of ideas passed off as a design.  There may be no logic that applies to the manlifter at all as to why the wheel size is different.  It may be as simple as they use smaller rear wheels in cargo trucks to provide a lower cargo deck height.    

RE: manlifter

Sometimes manufacturers use smaller wheels on tractor trailer units so they can increase the height of the load they can carry, due to clearances for underpasses, power lines, etc.  

RE: manlifter

(OP)
thank you very much for all your comments, i appreciated it a lot.

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