Using a motor to spin two discs in opposite directions

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The discussion centers on using a single motor to spin two discs in opposite directions for a vision show project. Participants suggest using a bevel gear setup to achieve the desired motion, where one disc is directly mounted to the motor shaft and idler gears facilitate the opposite rotation. Alternatives like rollers or belt drives are also mentioned, with considerations for durability and cost-effectiveness. The importance of maintaining speed while reversing direction is emphasized, with various mechanical configurations proposed. Ultimately, the user expresses gratitude for the guidance and feels their problem has been resolved.
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i want to use 1 motor to turn the shaft. lets say shaft turns clockvise, there is two discs on shaft. discs have to turn same speed reversed rotation. i drawed reverse clockwise motion. it is 1:5 slower than shaft. when i drawed other disc (rotates clockwise like motor) it turns speed of shaft so 5x speed.
Hi guys, i want to build small vision show i will use lasers. But stucked at the mechanics. i want to use 1 motor to turn the shaft. lets say shaft turns clockvise, there is two discs on shaft. discs have to turn same speed reversed rotation. i drawed reverse clockwise motion. it is 1:5 slower than shaft. when i drawed other disc (rotates clockwise like motor) it turns speed of shaft so 5x speed.

i will arrange this discs like clockwise, reversed clockwise, clockwise, reversed clockwise, .. 6-10 piece of discs.

My question is how can i do below disc to turn with same speed of reversed rotation disc?
Further question if you want to more helpful, Kindly i want to make this cost effective and durable am i going to right way?

Video of reversed; Top is reversed disc. below is not drawed.
 

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Welcome to PF.

Your solution seems overly complicated. If you just have the motor turn one gear that is in contact with another gear, the two gears will be spinning in opposite directions. And you can adjust the gear ratio of the two gears to set the relative spin rates.
 
berkeman said:
Welcome to PF.

Your solution seems overly complicated. If you just have the motor turn one gear that is in contact with another gear, the two gears will be spinning in opposite directions. And you can adjust the gear ratio of the two gears to set the relative spin rates.
Thank you, seems a nice forum thanks for supporting.

I guess I did as you said? I explained the mechanism in the picture below. The gear (red) connected to the shaft only turns the gear (yellow) that rotates on its own axis. I put 3 of these gears, it would have been one too. Then this gear turns the internal gear (blue). But since the internal gear has to have many teeth, it turns slower.

Ekran Alıntısı.webp
 
What you have designed is a planetary gearbox. They’re delightful for changing speeds, but not so much for changing directions while maintaining the same speed.

You will want to use a bevel gear setup, tbh. Have one disc mounted directly to the motor shaft, using a mounting bracket with an angled/bevel gear on it. Use 2 bevel gears as idlers between the discs, and mount them on a yoke or collar that carries a bearing, mounts to the platform, and holds the shaft steady. This also locks the idlers in relative position to the two discs and prevents them from drifting. Finally, mount the second disc on a bearing with an adapter to match the bevel gear found on the first disc. This should allow the discs to match speeds, but in opposite directions.

The other option would be rollers between the discs, also on a yoke or collar setup, again to keep them from moving around the drive axle.

I hope this makes sense.
 
Fundamentally a differential gear, but fix the input shaft solid to the chassis. When you drive one of the output shafts. The other side will counter-rotate.

A flat, or spur-gear differential, is optimised to be a flat sandwich with internal gears between the discs.

If you do not need to maintain an exact index between the discs, the gears can be replaced by balls that run on the disc surfaces, with the balls held in place by a thinner fixed plate, with holes drilled in it to house the balls.

There are also approximate belt drive possibilities, where one motor drives two belts, but one belt is crossed like figure of '8' to reverse direction. Rubber bands or 'o'-rings could also work.
 
Flyboy said:
You will want to use a bevel gear setup, tbh. Have one disc mounted directly to the motor shaft, using a mounting bracket with an angled/bevel gear on it. Use 2 bevel gears as idlers between the discs, and mount them on a yoke or collar that carries a bearing, mounts to the platform, and holds the shaft steady. This also locks the idlers in relative position to the two discs and prevents them from drifting. Finally, mount the second disc on a bearing with an adapter to match the bevel gear found on the first disc. This should allow the discs to match speeds, but in opposite directions.

The other option would be rollers between the discs, also on a yoke or collar setup, again to keep them from moving around the drive axle.

I hope this makes sense.
Thank you very much :)
 
Thank you, i will consider the options but gears more durable i think. My problem solved guys have nice many days :)
Baluncore said:
Fundamentally a differential gear, but fix the input shaft solid to the chassis. When you drive one of the output shafts. The other side will counter-rotate.

A flat, or spur-gear differential, is optimised to be a flat sandwich with internal gears between the discs.

If you do not need to maintain an exact index between the discs, the gears can be replaced by balls that run on the disc surfaces, with the balls held in place by a thinner fixed plate, with holes drilled in it to house the balls.

There are also approximate belt drive possibilities, where one motor drives two belts, but one belt is crossed like figure of '8' to reverse direction. Rubber bands or 'o'-rings could also work.
 
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