5 ms·
Is there a drive that does the opposite? A drive that converts intermittent rotary motion to continuous rotation? I never studied this sort of thing in school,
by Nicholas_C 13y ago
Is there a drive that does the opposite? A drive that converts intermittent rotary motion to continuous rotation? I never studied this sort of thing in school, unfortunately.
- asmithmd1 13y agoa flywheel? These are fascinating to watch: http://en.wikipedia.org/wiki/Hit-and-miss_engine http://en.wikipedia.org/wiki/Hit-and-miss_engine
- VLM 13y agogoogle for "four bar linkage crank rocker" and you're gonna need a flywheel on the rotating side. For some definitions of intermittent rotary motion. If you're ever bored, look at what four bar linkages can do. Stereotypical mech eng topic where its shocking just how many different things four chunks of metal and some bearings can achieve. A really poor analogy would be its kind of the turing machine of the mech eng world in that it can seemingly do almost anything with a minimal amount of parts. There is an interesting scaling effect where the math for linkages scales pretty scarily as the number of bars increases. (edited to add, and you can see an applied model in some stair stepper exercise machines where the arm actually moves thru an arc, which I guess is the intermittent rotary motion you're looking for?)
- TheLoneWolfling 13y agoYou can do this with a combination of a flywheel and overrunning clutch.
- deleted 13y ago[deleted]
- aidenn0 13y agoLook at your bicycle. It does exactly that.
- Nicholas_C 13y agoI think the key phrase is "intermittent rotary motion." The movement of the red wheel in the gif on Wikipedia is very unlike my legs powering a bicycle or a cars piston pumping up and down. I would like to transfer the movement from the red wheel into the smooth continuous rotary movement of the green wheel.
- sliverstorm 13y agoA bicycle can work like an intermittent drive, though. The coast capability of the cassette, combined with your mass as a form of kinetic energy storage, means that you can alternate between pedaling and not pedaling while continuing to move.
- sliverstorm 13y agoNo gear-set alone that can do that, because you need a storage element.
- Nicholas_C 13y agoCould you go into what that means?
- sliverstorm 13y agoFor intermittent motion to produce continuous motion, you need to store energy to have a supply of power for the lul when the input is not moving. Without energy storage, it is impossible to continue doing work on the output when the input is not moving. Does that make sense?
- Nicholas_C 13y agoDefinitely. Thanks.
- Arjuna 13y agoIs there a drive that does the opposite? A drive that converts intermittent rotary motion to continuous rotation? From the perspective of a mechanical watch, there is a component known as the mainspring. It is a spring that stores energy from either manual winding or automatic winding. With manual winding, turning the watch's crown to wind the mainspring is an intermittent, rotary motion. Alternatively, with automatic winding, a rotary weight that moves intermittently (e.g., when the wearer's arm is moved) is used to wind the mainspring. In either winding scenario, manual or automatic, the result is that intermittent, rotary motion causes energy to be stored in the mainspring, which is then subsequently available to provide for continuous rotation of the watch's mechanics.
- markild 13y agoGreat answer. I caught myself thinking along the lines of "of course it's not possible, that would be preposterous!", but as you say, a watch spring mechanism does exactly this. The key concept here is "stores energy".