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Pure mechanical no electronic conveyor scale

Pure mechanical no electronic conveyor scale

Pure mechanical no electronic conveyor scale

Hi, I'm busy building a rough conveyor packer of which the unit is semi mobile for quick packing and belt is driven with hydraulics, but not always access to electricity. The product will run along the line and drop into a box at the end for a packed weight of around 10kilograms. This box I imagined would then be held up on two angle brackets running parallel to the belt, that when it reaches the certain weight to open and drop the box down a shoot below. There also need to be a flap that lifts up at the end of the belt to stop the product momentarily while the full box is dropped and mechanisms reset. Once the full box has been dropped the brackets are lifted back into place a new box is pushed into place and the flap drops again so that the small build up of product on the belt can continue into the box.
I'm looking for advise or direction on how and what mechanical system to use for the weighing and dropping action, but then also to bring it back into place, and then also as the box drops to jerk the flap up once the box reaches its weight to stop the product. I know this can be easily done with the help of some micro controllers, but this will need to be done without electronics.
Thanx in advance to all the clever people on this great forum.

RE: Pure mechanical no electronic conveyor scale

"belt is driven with hydraulics"
What is the power source?
Other dimensions and weights of conveyor and other components?
What is being packed; trash?
Would you rather create an invention while sitting on a small deserted island or taking a tour of the Smithsonian Institute?

RE: Pure mechanical no electronic conveyor scale

Strong voiced my first comment: How can you have a hydraulically driven conveyor without an electrically driven pump?

Also, you're asking for a lot of mechanical action here and all you're providing is verbal descriptions. Do you have any diagrams or sketches?

As a mechanical engineer with 40 years experience I can tell you four things:
One, it is possible to design a mechanism that theoretically will do what you want.
Two, it will be complex, will require many manhours to complete, and will not be very portable.
Three, if it ever works reliably and repeatedly, it will only be after you have invested in extensive trials, development, and rebuilding.
Four, at some point in that process you will wish you had invested the same time and effort in coming up with a portable source of electricity, such as a battery or generator.

RE: Pure mechanical no electronic conveyor scale

Why not make the container immediately under the conveyor a box with a full hopper bottom? This hopper dumps quickly into the movable boxes below. The hopper box is sized for your load and its volume, and then the movable boxes have time to be moved during a new fill cycle. The hopper box is supported at two corners on fixed hinges or knife edged supports which prevent the box from moving laterally in that top plane. The opposite edge of the box is supported by compression or extension springs, and with sufficient vertical movement (rotational about hinged corners), this motion trips the hopper gate trigger, and the material stop gate trigger. The spring support will be weighing about one half of the hopper load, and this may take some adjusting of the way the conveyor feeds the hopper box.

It would certainly help if you would think about your problem a little more deeply and give much more detail if you really want serious help. We can’t see it from here and you’ve only given a vague idea of what you are really doing. What about some sketches, dimensions, materials being handled and their density, loose volume, etc. etc?

RE: Pure mechanical no electronic conveyor scale

Are you not talking about a trapdoor that has a latch activated by a certain weight and a spring-loaded return?

RE: Pure mechanical no electronic conveyor scale

Star for Jboggs.

To his comments I will add that the mechanism will require regular cleaning and lubrication, not unlike a steam locomotive.

Mike Halloran
Pembroke Pines, FL, USA

RE: Pure mechanical no electronic conveyor scale

Many years ago I recall seeing a system, driven my a single gas engine that loaded grain sacks.
It used belt drives, and an actual balance to measure the weight and trip the closure of the grain flow valve.
This thing even had an arm that came in and tied the top of the sack closed.
I am guessing that it was built in the 1920's and it was all mechanical.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Pure mechanical no electronic conveyor scale

"and it was all mechanical" except for the gas engine! I guess the OP is busy.

RE: Pure mechanical no electronic conveyor scale

Water wheel on a river someplace.

RE: Pure mechanical no electronic conveyor scale

The hydraulics will be driven by a 5hp engine for now.

IFRs, yes that is what I have now decided on.

It's easier to come up with ideas once it's partly built,and easier than trying to learn Inventor for prototyping.

I've managed to get it working by only using some springs with the right tension and it's light weight enough that it hangs off the end of the conveyor, and can be attached or removed by 1 person.

My apologies for not clarifying better in the first post, but had to first have the self doubt which then gave me the drive to just get it working, and thankfully it did.

Thanx for all the comments.

RE: Pure mechanical no electronic conveyor scale

Do you fancy uploading a video to YouTube and posting a link? We like it when things work.


RE: Pure mechanical no electronic conveyor scale

I have the mechanisms sorted out, now just the assembly. Once thats done I will surely upload the final product.

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