darkboy101089 Posted July 14, 2015 Posted July 14, 2015 (edited) This is a remote controlled car that I am working on. This is the demo of the 3 speed automatic gearbox that I tried to improve for this project. It uses a differential gear to transfer the overload torque to select lower gear. http://www.brickshelf.com/gallery/darkboy101089/Gearbox/imag0245.jpg http://www.brickshelf.com/gallery/darkboy101089/Gearbox/imag0246.jpg http://www.brickshelf.com/gallery/darkboy101089/Gearbox/imag0247.jpg http://www.brickshelf.com/gallery/darkboy101089/Gearbox/imag0248.jpg http://www.brickshelf.com/gallery/darkboy101089/Gearbox/imag0249.jpg Current WIP http://www.brickshelf.com/gallery/darkboy101089/Gearbox/imag0251.jpg Edited July 14, 2015 by Blakbird : Replaced oversize images with links. Quote
darkboy101089 Posted July 14, 2015 Author Posted July 14, 2015 This is a video demo of how the gearbox functions. Quote
Alasdair Ryan Posted July 14, 2015 Posted July 14, 2015 I recommend that you should be testing any gearbox that will be propelling a car along should be tested on the ground,and not static like in the video. There are two ways I have often thought about building the most efficient auto-gearbox: Design A The Centre shaft is the one that changes gears,the top is a static axle from the motor and finally the lower axle is where the different output speeds are placed. Design B A orbital gearbox where the driven axle goes through gearing on a rotational axis which meshes to a static output shaft. I have tried your idea too but have found that there is not enough force to change gears,design A does work well but it is limited as a lot of gearing will make gear backlash. Keep it simple.... Quote
darkboy101089 Posted July 14, 2015 Author Posted July 14, 2015 (edited) I know orbital gear are more efficient and works better, but I like the sound of it clicking to new gear I did test it on the floor and found out that lowest gear does not get selected often, but when I initially throttle the car, it selects the middle gear and goes back to fastest gear after one second. The only time I see lowest gear selected is either going over a bump or putting lots of load on the car. The spring on the rubber band to change gear must be precisely place to achieve the results that I got. Slightly too hard on the force of rubber band can cause the gear to not be able to select lowest gear. Also the gear selection trigger is reinforced from what I initially started to achieve this. I am still working on improving it with minor changes at a time. Edited July 14, 2015 by darkboy101089 Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.