Wax motor
en.wikipedia.org
en.wikipedia.org
These are two separate things: thermostat will close and open based on surrounding temp., the actuator on the other hand opens and closes based on energizing a heating element that is driven by a separate thermostat.
Wax motors are pretty cool things. They rarely fail and do their job even in damp environments. I take care of my better half's hotel with approx 100 of these installed and we replace one of these once every couple of years.
But now that Wikipedia is becoming more stable, I wonder if this policy is still pushed as much. My understanding is that on all articles there is an army of autistic and obsessive people who will make sure it stays clean (I mean it in a good way), so if you mess things up, it won't last long, as in, seconds.
Thermostatic valves are ambient at both sides - they expand and contract naturally with the existing temperature, so they are not motors per se, because there's no actuation beyond the temperature.
Edit: also, the actuation from the wax motor only happens while it is absorbing (or losing) heat, even if it later ends up in a steady state with no heat flux.
That's why it's a motor, like in dishwashers, not a thermostat like in e.g. greenhouse windows or radiators.
It doesn't need to be persistent, but without some way to create a state that is different than ambient, it's not a motor.
Also you seem to have a miscommunication with the person replying to you where they are talking about a spacial thermal gradient and you mean it in a temporal sense.
EDIT: the way I see it, talking about gradients here is nonsense. The wax motor works by expansion/contraction due to point temperature. No gradient is involved. Gradients are thermostat-level thinking, and even then, in the greenhouse scenario, there is no gradient to talk about, because the whole point is just to vent the heat from inside to outside when inside crosses certain absolute value of T, and the only "gradient" that matters is the assumption that outside side is less than T at all times.
things lietrally change its volume maintaining mass when its temperature changes, due to atoms moving more energetically, like something be 4x4x4 inches at 40F, but 4 1/16 x 4 1/16 x 4 1/16" at 200F
this isn't a Stirling engine with a displacer, just a sealed off piston
There are commercial thermostats where the wax element itself is both the temperature sensor and the actuator, eg Thera-100 T1002W0.
I had to replace about half of them within the first ten years of usage in our floor heating. It may have been a bad batch, but I would definitely not claim that the rarely fail. My car did not fail once during that time.
The idea is that so long as the washer is providing power the motor stays locked. But if you ever loose power within a few minutes you can open the door if you had to.
Thus moved solar-thruster
> Its principal application is in automotive thermostats used in the engine cooling system.
So far, the game in town has been primarily hydraulics or electromagnetics, and the things that replace them are better hydraulics and better electromagnetics. Alternative actuators are either super niche or fail to leave the labs.
The second sentence also fits for field effect transistors and solid state electronics in general.
In the spirit of grimdark steampunk, have you ever heard of pneumatic logic? I still see these systems operating normally in some older mechanical rooms, it’s cool to see them still working after 40-50 years.
On the other hand one might as well associate it with “solar punk”, especially when powered by ambient temperature.
Does the originator, cyberpunk? Lots of cyberpunk stories present us with a society that is dominated by a digital abstraction. But the protagonist is special, so, they might not be.
The use case for the full unmixed hot tap is hygiene (usually washing face and shaving).
I also don't want any hot water mixed in when I'm washing my hands. The water coming out of the unmixed cold tap indicates the ambient temperature of the pipes. That's a feature, not a bug.
I'm already upset enough about what the water heater water is doing to my skin and am about to go tankless under my bathroom sink!
That's by far the more practical option anyway if we truly cared about the problem instead of fawning over engineer porn. The problem is solved. This is pointless engagement about temperature preference masquerading as something more interesting.
There's been studies demonstrating that soap is what matters.
Push/pull adjusts volume, rotation adjusts hot/cold mix
The problem is that the hot temp varies widely (and the cold temp varies slightly as you drain the house tubing reservoir and begin drawing ground-temp water).
The goal is that the water in the basin is the correct temperature, not the stream filling it - which means you need to compensate every time based on how much cold is already there before the hot water arrives. And that varies seasonally.
The time it takes for hot water to arrive tends to be a big proportion of the total time the tap is running, so you actually don't want controlled 40C water once hot water arrives. Perhaps if you had instant hot water, this would be useful.
The slow closing prevents water hammer, at least in water systems. In air systems it might just prevent a blast of back pressure blowing all the dust out of your vents onto your carpet.
I was drilled for several minutes by an interviewer who was trying to get me to use the ONE PARTICULAR WORD out of the entire English language to describe something - something I had 100% already specified.
If his manager hadn't been present, it would have ended with me not getting the job (and potentially a homicide) (which a jury trial would have acquitted, after I let him cross-examine me).
TWO HUNDRED SEVENTY FIVE years ago
in 1752, wow
(but they had no idea why it worked)
* https://en.wikipedia.org/wiki/Franklin_bells
Before the storm, the device would ring to remind Franklin, who had been obsessed with the study of lightning, urging him to chase the lightning
ha "chase the lightning" needs to be a catchphrase
It's a simple mechanism that used buoyancy to either open or close valves as water level changes in a container.
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
Mayne you know, are the internal components already designed with corrosion in mind?
> When a cycle is started, a wax motor is actuated pushing a pin outward and locking the door. This design has cost, reliability and safety advantages. In moist conditions a wax motor costs less for equivalent reliability than an electromagnetic solenoid or motor latch. It has a predictable passive release delay. If power is lost the door remains briefly locked, designed to be longer than the high speed spin cycle coast-down time, then reliably unlocks as the wax cools.
I've struggled to protect eletronics. Waterproof enclosures all fail over time. Though I have some ideas for immersion in mineral oil. But finding actuators that could work has been a bit of a struggle. These look cool, though maybe not something one could run off 5V :) Ill keep looking around
It collects moisture from the air, distills the water out of the silica gel and stores it- then releases it in the evening to plants at the root. A terraforming rock, printed in-situ, with materials available in situ (well except silica gel, optical fibers and wax-motors).