Gearbox for FRC Denso Throttle Motor by dirtyvalentine

Last crawled date: 3 years ago

This gearbox was designed to work with the Denso Throttle Motor that is given out with the Frist Robotics KOP for several years. The gearbox housing and gears are entirely 3D printed using PLA plastic. PLA seems plenty strong for the limited power this motor has. After running and loading the output shaft of the gear box for several minutes I saw no degradation in the printed gears. There are two sets of gears providing a gear reduction of about 10:1 and 18:1. The total weight of the motor and gearbox is less than 1lb.
The gearbox and gear files are available to all FRC teams complements of "Andromeda One - TEAM #4905". Our only request is that if you print or use the gearbox that you post a picture on our facebook page: https://www.facebook.com/frc4905
Also, if you have any suggestions for improving the design please post them here on Thingiverse. I still have some more torture testing to do, but honestly I think it is way over designed. As time allows I will look into improving and minimizing the design. Any positive feedback you can provide is appreciated. Good Luck!
UPDATE: This gear box was used successfully on our Steamworks robot to open and close doors that delivered gears to the steam ship. After having issues with limit switches not working, we just hard opened and closed the doors at about 50-70% power to hard stops. I thought for sure this would be hard on the gear, but after an entire season which included going to worlds both gear boxes operated flawlessly. After much more use post season the gear boxes were removed and the gears were inspected. The gears looked like new, and no wear could be detected. FYI - we used "Super Lube" to grease the gears at the beginning of the season.
UPDATE 2: The shaft shown in the picture was 3D printed for display use only. You will probably want to swap that out for 1/2" hex stock (Al or Plastic). The gears were designed for VEX ROBOTICS 1/2" thunder hex. Regular 1/2" Hex will work, but you may have to file the hex shape in the gears to make it fit. You also need to swap out the round flange bearings with 1/2 Hex bearings such as Item# 217-3875 from VEX. To keep the shaft captive to the gearbox you can use either 1/4-20 bolts and fender washers tapped into the ends of the shaft or use 1/2" hex shaft collars (such as VEX item #217-2737).
The shaft used for the gear mated to the motor pinion was simply cut from the smooth shaft of a 1/4" bolt. A thin 1/4 ID brass sleeve was press fit into the gear as a bearing surface for the 1/4" bolt. Wish I had pictures, but the gearbox was disassembled and the parts were lost long ago.