Seems this would make it possible to make a relatively cheap waterproof actuator if you made it out of something corrosion resistant?
I've been looking for actuators to use in damp/wet environments and sealed actuators are rather expensive and supposedly don't last too long
In washing machine application the locking action is quite fast as the heating element is PTC connected more or less directly to mains, pretty substantial amount of energy gets dumped into the wax over few AC line cycles. In that application (and also in most industrial automation situations) ~100ms is more than fast enough because when most of the effector components are AC powered you end up with ~40ms worst case actuation delay just from the physics of AC electricity. On my washing machine it is quite noticeable that when you press "start" the door gets positively locked well before the capacitive sensing "button" finishes playing its haptic feedback non-sense. (the fact that front panel of cheap-ish toploading washing machine is actually a huge touchpad with haptic feedback that is designed to look and behave like five physical buttons says many things about economics of manufacturing stuff for that somewhat hostile environment at these scales)
oh interesting - I didn't realize PTCs can be used that way safely. I thought it hits a target temperature and then will continue heating at that temperature (which in your scenario would be unsafe). Maybe for my usecase it'll be hard to find a suitable actuator b/c I have a 5V system running of battery (looks like 12V ones do exist though)
geokon · · focus · HN ↗
I've been looking for actuators to use in damp/wet environments and sealed actuators are rather expensive and supposedly don't last too long
bartread · · focus · HN ↗
geokon · · focus · HN ↗
Mayne you know, are the internal components already designed with corrosion in mind?
dfox · · focus · HN ↗
geokon · · focus · HN ↗