Mounting Planetary Set Between Two Pinions
Mounting Planetary Set Between Two Pinions
(OP)
I'm currently studing options to retrofit a drive train for a tipping mechanism on a slag haulage car. The slag pot tipping mechanism consists of a parallel gear train driving a worm that rotates a pinion on a rack, which is fixed to the slag pot. So, the slag pot rolls on a rack and pinion to dump the load. This means that it translates and rotates simultaneously to dump the slag. One of the options I've proposed is to remove the existing drive train and add another rack and pinion with a top-mounted rack that runs parallel to the exing one. I would then mount a hydraulic geared motor (planetary set) between both pinions, keeping it free from the frame of the car. So, the motor freewheels between the pinions. Since the second rack is top mounted, it compensates for the direction opposition.
One of my colleagues believes that this is not technically feasible, since one pinion would rotate faster than the other and bind the system due to the gear ratio developed in the planetary set. However, I'm having trouble visualizing this. As far as I can see, there will be a relative difference in velocity between the input and output. Since the input is mounted on one pinion and the other is mounted on the second pinion, I believe the system will balance itself out, since each pinion should share the torque equally. I don't believe that one pinion will rotate faster than the other, since the motor is not fixed to anything other than the pinion.
Can anyone weigh in on this? Has anyone ever done this?
One of my colleagues believes that this is not technically feasible, since one pinion would rotate faster than the other and bind the system due to the gear ratio developed in the planetary set. However, I'm having trouble visualizing this. As far as I can see, there will be a relative difference in velocity between the input and output. Since the input is mounted on one pinion and the other is mounted on the second pinion, I believe the system will balance itself out, since each pinion should share the torque equally. I don't believe that one pinion will rotate faster than the other, since the motor is not fixed to anything other than the pinion.
Can anyone weigh in on this? Has anyone ever done this?





RE: Mounting Planetary Set Between Two Pinions
what benefit do you see in driving 2 pinions from the same planetary fed motor? I don't see any at all. why not just use 1 pinion of the proper size?
RE: Mounting Planetary Set Between Two Pinions
RE: Mounting Planetary Set Between Two Pinions
RE: Mounting Planetary Set Between Two Pinions
RE: Mounting Planetary Set Between Two Pinions
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RE: Mounting Planetary Set Between Two Pinions
RE: Mounting Planetary Set Between Two Pinions
RE: Mounting Planetary Set Between Two Pinions
But I'm still lost on this bit...
My understanding is that the existing system has only the bottom rack, and the motor drives the pinion on your giant teacup. IE: Motor moves with the slag pot. I don't understand your proposed new drive system. It's going to drive both pinions? Aren't they already affixed on a common shaft?
Ignoring how you drive this for now, and assuming the pinions are fixed to a common shaft:
With the pinion shaft driven at angular speed w and gear pitch diameter Pd,
The pot will translate at w*Pd/2.
The top rack will translate in the same direction at w*Pd. (Twice as fast)
RE: Mounting Planetary Set Between Two Pinions
RE: Mounting Planetary Set Between Two Pinions
What does this mean?
The hydraulic gear motor has an output gear that is wide enough to engage both pinions?
What does the second pinion and rack even do? If that rack is grounded, the entire thing cannot move.