Toughbox Gearboxes

[GillSt.Bernards]

Whenever we turn the robot on the axel with one of the gear pops out and that falls down. The ball bearing has not popped out except for the first time today. Any reason why this would happen?

[MrForbes]

Did you put the bearings in the right way, with the flange on the inside of the transmission, so they can't fall out?

[Zflash]

http://lib.store.yahoo.net/lib/yhst-...rGuide2009.pdf

Above is a guide on how to assemble the toughbox. Hope this helps.

[GillSt.Bernards]

yup they are on the inside

[GillSt.Bernards]

according to the instructions they are assembled the right way but the axel is still popping out

[AndyB]

Just double checking, which gear and shaft is popping out? There are normally 4 gears in a toughbox and are driven in the following order:

CIM 14 tooth (On the motor) drives a 3/8" Hex 50 Tooth gear which is on the smaller of the two shafts.
1/2" Hex 14 Tooth on the same shaft then drives a 1/2" Hex 50 Tooth gear which is on the output shaft.

The more detail you can give me, the more I can help you. The other thing I could see is the output shaft pulling out if you really wore down some areas. But this is pretty unlikely. The other likely option is that the gear on the motor is pulling off, which would be the result of a missing key/retaining ring. But that doesn't really go with the bearing/shaft problems your talking about.

The more detail you can give us, the more help we can provide.

[Engineer]

We've had the push nut on the motor shaft works it way out until the key fell out. This cause one of the motor to spin freely. The only issue I see is the push nut. I'd prefer a set screw or event better an E-clip design but that would require machining the motor shaft. Some teams may not have the resources for machining the shaft.

[Moheeb698]

Originally Posted by Engineer

We've had the push nut on the motor shaft works it way out until the key fell out. This cause one of the motor to spin freely. The only issue I see is the push nut. I'd prefer a set screw or event better an E-clip design but that would require machining the motor shaft. Some teams may not have the resources for machining the shaft.

That happened to us as well. We fixed it by stacking some washers (each one with a key notch) and then we just put that in with the gear and it helped.

I know I'm forgetting some details here because I didn't do this myself, but when I find out exactly how we fixed it I'll repost.

[GillSt.Bernards]

Thanks we will try these at the meeting tonight and see if it makes a difference

[Akash Rastogi]

http://www.chiefdelphi.com/forums/sh...7&postcount=10

Is this the type of problem you are referring to?

[GillSt.Bernards]

No it's not the keys. we had that problem last year in which we lost the keys and we could not find them.

[Engineer]

Originally Posted by Moheeb698

That happened to us as well. We fixed it by stacking some washers (each one with a key notch) and then we just put that in with the gear and it helped.

I know I'm forgetting some details here because I didn't do this myself, but when I find out exactly how we fixed it I'll repost.

We stacked washers on both sides of the gear. Even if the push nut comes off, the gear and key cannot because the plate on the far side will not let the washers slip off the motor shaft. The last washer has to be larger than the hole in the far side plate.

[Cory]

Originally Posted by Engineer

We've had the push nut on the motor shaft works it way out until the key fell out. This cause one of the motor to spin freely. The only issue I see is the push nut. I'd prefer a set screw or event better an E-clip design but that would require machining the motor shaft. Some teams may not have the resources for machining the shaft.

We vastly prefer those splined retaining rings over any other method that can easily be done with the CIM shaft.

The only thing better in my opinion would be a snap ring, which isn't possible to do without disassembling and permanently damaging the motor.

[NorviewsVeteran]

One of our toughboxes had a problem with the key in the motor shaft jumping out and getting stuck in th grease on the inside.

It can be a good idea to put duct tape over the extra holes (keeps dirt out and keys in).