Ball Shifters - Any Ideas

[dagronlund]

My robotics team is considering developing our own ball-shifting gearbox over the summer for next year's robotics season but we were wondering where we should get the ball-shifting mechanisms from (specifically the shaft with the two gears and the pin for switching which gear is engaged). We used the VexPro ball-shifters this year and we know that their ball-shifting mechanism works great, but we were wondering if there was anybody that sold ball-shifter kits so that you could attach other types of gears or even pulleys to the shaft. Any ideas or thoughts would be greatly appreciated.

[Seth Mallory]

The students on my team designed and built the shaft and the rest of the ball shifter. They changed the shaft to one piece and used ball bearings instead of some of the bushings. They did buy the gears. Look for a description in the extra discussion section under 192 gear box. There is also a good write up of the design processe. Good luck and have fun.

[asid61]

You can buy the stuff from Vex like gears and shifter shaft.
Or you can take apart a Vex ball shifter and replace the housing/ gears with your own choosing.

[Dr.Gusta]

Originally Posted by asid61

You can buy the stuff from Vex like gears and shifter shaft.
Or you can take apart a Vex ball shifter and replace the housing/ gears with your own choosing.

http://www.chiefdelphi.com/media/photos/40245

If you scroll to the bottom of this post you can see the near final CAD rendering of a modified ball shifter. We kept the shifter internals mainly stock but added a bevel drive and a custom enclosure.

[asid61]

Originally Posted by Dr.Gusta

http://www.chiefdelphi.com/media/photos/40245

If you scroll to the bottom of this post you can see the near final CAD rendering of a modified ball shifter. We kept the shifter internals mainly stock but added a bevel drive and a custom enclosure.

Oh, I liked that gearbox. What was your final weight, by the way?

[Dr.Gusta]

Originally Posted by asid61

Oh, I liked that gearbox. What was your final weight, by the way?

We have yet to manufacture that one. We were a rookie team this year and just were spit-balling on issues we had and how to fix them. Motors pertruding into the electronics was one and this was kind of a concept drawing that got very out of hand. It is all 1/4in alum so it will not be too heavy, the bevel gears will add a bit of weight though.