[Syphonics]

The attached picture is the sloter.
Abrasive paper will be feed into the tray indicated by the red arrow, then the piston is attached to a plate that pushes individual paper out.
How do i make the paper comes out more forcefully? Because my application required a certain amount of force from the sloter. Increasing the air pressure doesn't helps.

[vger]

Interesting device. Is the abrasive paper small squares? How much pressure is there holding the paper against the back plate? Which way does the abrasive side face?

[Syphonics]

the abrasive paper is small squares, the abrasives side is away from the sloter. The force on the back plate is yet to be determine.

[vger]

Many years ago I worked on IBM and other brands of keypunch machines. They had to deliver the punch cards one at a time into the machine. One of the best and least troublesome feed mechanisms consisted of a flat plate that the cards rested against, much like your machine but a bit larger plate. The plate had a very shallow step machined into it (.004") that would catch on the edge of the first card. The card rested flat on the plate and the plate was positioned about .007" away from a flat stop that kept the stack of cards from being pushed. This way the only friction was the card sliding on the next card in the stack. The plate would extend just enough to get the card to catch on pinch rollers that would take over the transport of the card. Of course you will not have the rollers, but the friction should be much less as long as the slide extending out the bottom is not a problem.

[One of Many]

A larger cylinder bore or mechanical advantage. Although using a fulcrum point for a mechanical advantage will require a cylinder with a longer stroke and the motion is no longer linear or in a straight line.

A reduction in friction if possible? The use of aluminum sliding on aluminum may not be the best for wear. Even more so when an abrasive needs to be transported. Teflon, Nylon, Poly's and UHMM (Plastics et al), make great bearing slide liners for reducing friction on light sliding members.

I suppose it also depends on the source of the resistance in pushing a single sheet? This may be due to tolerances in the sheet dimensions and thickness.

Then again, I cannot tell you how many times I had the challenge of overcoming one problem only to introduce another.

DC

[Syphonics]

currently my device is able to slot out the paper, but i need the paper to be punch out forcefully. currently it is just like pushing it out or droppping out.
Do i need to introduce a certain resistance to have the paper punch out forcefully?

[vger]

Oh... you need more speed. If more air pressure doesn't make it, then you may need more air flow. Larger air line, and a valve with a larger orfice for increased airflow perhaps.

[One of Many]

Without observing the process in action, I don't think anyone will be able to give good advice towards a solution with the components involved.

I cannot tell if the paper is having a slot punched through it or if it is just being stacked in the slot. Maybe post a sequence of pictures that helps clarify the progression of the paper through your device? What/where/when the paper starts out, what the machine does and the results you expect.

DC

[Syphonics]

sorry for the late posting of the images.
but this is the .gif file
the abrasive paper is not feed in yet becasue the spring mechansism is not done up yet.
how do i enable the paper to be push out more forcefully.

[One of Many]

What does the guillotines press action do to the paper? Feed, fold, cut, punch one small sheet at a time?

If you are laying a stack of the abrasive sheets in the track/magazine horizontally, then apply a spring force to move the stack into the guillotine. I think this will increase friction between the sheets themselves. Often a vertical stack using gravity alone can keep the stack compression to a minimum. Too much pinch friction on the stack might add to your problem of pushing the sheets past what ever they are captured between.

A greater force on the end of the guillotine pusher will take a larger cylinder than you now have. The force on the pusher going down is a factor of the piston area and air pressure you are applying. If you are using 100psi on 1 square inch of piston surface you get 100 lbs of force. 2 square inches of piston surface with the same 100psi of pressure will give 200lbs of force. This works the same no matter what units of measure you are comfortable with.

A 1.25" piston has an effective surface area of 1.227 square inches. A 2" piston has 3.141 square inches. The exponential gain in area verses bore will apply quite a bit more force at the point of interest with no increase in air pressure. To calculate, the area = Pi*radius squared.

DC

[Monomer]

What type of cylinder are you using?



If it's a standered (Bimba) type, switch it out to one with a larger bore.

[vger]

I agree that a larger cylinder will give you more force for a given applied air pressure. For the same length of stroke you will also use more air. If your tubing and valve are small in diameter, it will take a longer time for the cylinder to make the stroke. Many production lines use air cylinder bumpers to select, reject, divert, or otherwise change the direction of materials. When rapid, forcefull movement is required, a large orfice solenoid valve and relatively large piping is used. In one case I solved a speed issue by using a larger solenoid valve, with an accumulator attached just up stream of the valve, and a larger pipe to the solenoid. It had to extend 2 inches, knock a pop bottle off a conveyor line, and then retract, all within 1/4 second. You can have 100 PSI available for pressure, but if it takes 2 seconds to fill the cylinder because of a tiny orfice in the valve, it will take 2 seconds. Picture this.... Connect a 1" inch pipe directly to a 100 psi compressor tank with a 1" ball valve on it and open it up... (make sure you have your ears covered) it wouldn't take long to fill a 50 gallon plastic bag. Now take some adapters and attach a solinoid valve with a 1/16" orfice in place of the 1" ball valve and time how long it takes to fill the same 50 gallon bag. You can lift a car with 100 psi and a large enough cylinder, but if you want to throw the same car with 100 psi, you better have a large pipe for the air.