This has been already discussed on SWGeeks.com so I thought of putting it in form of an article so that other can refer this.
Can Crusher: A can crusher is a device used for crushing aluminum soda cans for easier storage in recycling bins. While most recyclers don’t require you to crush cans, if you do recycle a lot, your normal bin may fill up quickly. The can crusher gives you extra space by flattening either single or multiple cans.
The first can crusher was of course the human foot. People often stomped on cans to flatten them down either for recycling or for greater space in the garbage can. This could sometimes hurt if the foot did not come down properly on the can, so entrepreneurs eagerly sought a variety of alternatives that could be used with the hand.
There are many types of can crusher viz. mechanical, hydraulic. The one discussed over here is one of mechanical type which has two gears (having rotary and linear motion, driven by a hand wheel). The can is crushed by forcing it against solid plates which moves along with the gears.
As this post is all about animation, I’ll not go into details of how to model the parts. This post focus mainly on rotary and linear movements/motions of the two gears. Some of parts have not been shown / modeled for clarity purpose. I’ll be using the files shared by Lavanya on SWGeeks.com
The parts used for this animation are Side Cover (not shown in the pic below), Cover/Body, Rack, Gears and Hand Wheel.
1. Start a new assembly and properly mate the following parts viz. Cover/Body, Side Cover and Rack.
2. Insert the two gears (with shaft and without shaft) in the assembly and position them appropriately.
3. Create a gear mate between both the gears. Make sure the ratio is 1:1. You have to place the gears so that there is no interference.
4. Insert the hand wheel and mate it with the Gear (with shaft) so that both can rotate/move w.r.t each other (for further steps, I have the hand wheel hidden for better clarity).
5. Now is the real trick. Don’t use Rack and Pinion mate in this animation as that will not work. Gabi already pointed it out on here blog. Instead of Rack and Pinion mate, I have used two distance mates. Create two distance mates between gear axis and side face/cover. The distance value for both the mates should be same.
6. Add an angle mate between the side face and corresponding parallel plane of either of the gears. I have used plane of gear (with shaft).
7. Now you have completed most of thing and it’s time to do some animation.
8. Switch to animation/motion study mode and set the view orientation.
9. Drag the time line to some distance (w.r.t. time). I have set to 5 seconds.
10. Change the value for all the three mates, two distance mates (changed values should be same) and third that angle mate (you can change the value to 360°).
11. Click on Calculate and then finally you can enjoy with the animation.
Wow, the gear are rotating along with hand wheel as well as moving forward. Here is the link to video.