The sawtooth thread is more commonly known as a buttress thread, based on the rest of the construction I'm assuming the unit operated under fairly high pressure, that thread would allow for very high axial loading with a minimum of torque on the cap. In some cases a buttress thread can also form a seal if the fluid it's containing is suitably viscous, but that would not be the case with any gasses in cryogenics, thus the welded face. The thread was probably just used as an added safety feature and for ease of assembly.
Stirling coolers are normally loaded with pressurized helium in the 435 PSI range so the threads have a meaning but they are still little over the top for the pressure after all, ordinary threads would have worked just fine as I see it. The lid is never removed when it is pressurized so that part would not matter.
it is cryoengine that is connected to Stirling Engine push pull . The double tubing - the outer one was evacuated permanently at the time of assembly. The inner one was delivering pulsed stroke to double chamber in out double action Stirling cooler - however in later versions the outer tubing was cooled ( pre cooled) by the chamber back instead of being evacuated. the radiator of "cold piston" was a cold finger by itself. Wesley
Those threads are called buttress threads and they are stronger in one direction than the other. They are used in punch presses for adjusting the position of the ram because they experience heavy impact forces as part of their design.
This kind of thread actually is called saw tooth tread, it is used when a thread has to withstand high force but only in one direction. You often see this kind of threads on excavators that go only one ore two floors up and down. The sytem is nice cause you dont really need any sort of emergensy break cause threads are so unlikely to fail and most often there are two of them onne on each side.
this was really great, for years i've been wanting to get myself a small self-contained crycocooler to liquify gasses so anything regarding them is always interesting.
The fact the rattling stopped when you put pressure on the piston seems to indicate it's designed to be under backpressure. Probably quite significant backpressure given it's tiny displacement.
LPFthings The threads and the ceramic sleeve give it away. I don't think this is designed to work unless under very high pressure. Pity the second sticker was removed, i bet it had info on it.
That is not the hot end. The system is basically a compressor driver for a displacer piston moving in the remote cold head. This is an older split Stirling (not Sterling) cycle unit. Both cooling and heat rejection happens on the remote cold head. This is a push pull pump that feeds the cold head with necessary oscillations where the Stirling magic happens. Usually charged with helium or CO2 and at a very high PSI not vacuum.
I think the threads are shaped like they are to handle high pressure. their profile means that its a flat pushing on a flat when the cap is under pressure from inside.
Very awesome teardown! sadly I saw nothing to help you date it or anything, but man it's sure neat! My guess is due to the low volume these were likely made in, and the insane amounts of money these had to cost, we probably won't find out specifics until someone who worked with one of these specific units sees your video. My google searches have come up generally fruitless, but I may continue anyway.
threads like that are used in applications that need to be gas tight without contamination from a sealant. They are only good one or two times because the thread profiles of the screw and nut don't match. They wedge the two pieces together and the metal distorts. These aren't designed for aluminum. That may be why they needed to weld it.
This is awesome. Looks like a really well made piece of kit, albeit made only to last a set of brushes. It's almost as if 2 different companies made it!
The coaxial tube is possibly used for insulation reasons. Cryogenic fluids are (of course) very cold. Maybe the tube was vacuumized to prevent thermal loss.
Behold, The 2 by 4 of science! I'll bet the big flywheel is there to even out the running speed. The motor could run the piston on it's own but there would probably be a big variation in speed on the compression stroke vs the expansion stroke without it.
the flywheel is to keepa constant speed and more torque to get the compression stroke, it's easyer on the motor. the motor and bearing sealings and lube are built to operate at extremely low temps.
The flywheel is probably to smooth out the high torque load as the piston approaches TDC so that way the crank spins at a more constant speed rather than slowing down and speeding up every rotation
It was built to hold as long it was humanly possible and this was what they could come up with in those days. It was still not that long time due to fex carbon brushes and what not in comparison to todays crycooler in similar build that of course use brushless motors and other things that doesnt contaminate near as much and thus have a much longer life length.
Cryocollers are stirling engines guess this was too. The interesting thing in stirling engines is it can work in reverse. Actually reverse means cooling using power, normal mode converts heat difference to power. So you could use a cryocooler as a generator if the motor inside can work as a generator.
assuming proper lubrication (removed for disposal because of toxicity) this motor and its brushes would last 30+ years before service or replacement, ive seen cases where brushed motors outlast brushless ones simply because of high end lubricant and lube designed brushes, now this unit was either removed because they switched to brushless or because it was at the end of its service life, because the lubricant would likely be flushed with the brush material we can presume that the black brush material in the end was from you and your friend running it, if it was at the end of its life and they went with brushed again that would be because of the simple startup and high start torque without drive circuitry, depending on the use this may have been only used to keep the cold on wile the power was out in large cryo systems, i.e its easier to run a dc load than to convert to ac or 3 phase ac, no driver required, and with most dc motors if they fault under normal conditions you increase the amperage and take note that that motor needs replacement as soon as regular power is returned either with a fuse that is then upgraded or a controller that reads current and activates a light to indicate failure
I was expecting that coaxial tube to connect in some way to the 2 holes in the internal plate, fridges often have a coaxial tube, especially the absorbtion fridge circuit, i was guessing the outer to be low pressure side, with the inner as high pressure. actually, i would guess the part that the pipe connects to has the valves for flow direction.
One thing I notice, there is a strange buzzing noise being picked up by your camera's microphone in the video. It is more noticeable when the mic is close up the device, even more noticeable when you touch the lamp at 6:36 . The noise changes as you move around. It does matter because these kinds of noises cause me a nightmare. But I can't stop watching your awesome vids!
dumle29 I would guess that the space between the tubes was evacuated for thermal isolation as only the inner tube actually connected to the piston cylinder.
Paper weight, come on tesla500....... that is one nice dc motor. Use some of your skills and use it in a build that requires a strong drive motor, perhaps get rid of the concentric drive and mount a spocket, pinion or pulley. Its just way too nice to use as a paper weight. If you do fabricate an idea be sure to post a video of your build. Cheers!
I looked at this video sitting in a comfortable soft sofa, having a nice warm felt over my legs and some good food in front of me and then just enjoy this movie.
If they are designing it to not be serviceable, then those units would likely not sell unless they price them in the $40-50 range at the highest when they are brand new.
Razor2048 I believe the motor was designed separately from the enclosure. You don't bother with screw adjustment on brushes when you purposely design it to never be opened. However, there's another possibility. Perhaps the threads were not enough and they decided that a welding was needed on top of the special thread.
The materials are worth FAR MORE than 50 dollars. This little device is easily many thousands of dollars new. when you exit retail and enter into commercial use. The price tag doesn't matter. The end user NEEDS it. There is no competition. The part must be designed, engineered and lastly fabricated. The costs of all of those things need to be rolled into the cost of the final product. If that pump costs less than 12k id be flat out amazed. If it cost 120k i would be not that surprised.
laurdy I agree. Indium seals are typically used in cryo applications because of their malleability at very low temperatures. Helium will find the most minute of leaks and is used for leak testing in hermetically sealed systems because of this.
The sawtooth thread is more commonly known as a buttress thread, based on the rest of the construction I'm assuming the unit operated under fairly high pressure, that thread would allow for very high axial loading with a minimum of torque on the cap.
In some cases a buttress thread can also form a seal if the fluid it's containing is suitably viscous, but that would not be the case with any gasses in cryogenics, thus the welded face. The thread was probably just used as an added safety feature and for ease of assembly.
+Zander Horn i cant seem to upvote you
Stirling coolers are normally loaded with pressurized helium in the 435 PSI range so the threads have a meaning but they are still little over the top for the pressure after all, ordinary threads would have worked just fine as I see it. The lid is never removed when it is pressurized so that part would not matter.
Cool teardown. I agree with the others -- the gasket residue is likely pure indium metal for containing the helium.
I see what you did there.
it is cryoengine that is connected to Stirling Engine push pull . The double tubing - the outer one was evacuated permanently at the time of assembly. The inner one was delivering pulsed stroke to double chamber in out double action Stirling cooler - however in later versions the outer tubing was cooled ( pre cooled) by the chamber back instead of being evacuated.
the radiator of "cold piston" was a cold finger by itself.
Wesley
Those threads are called buttress threads and they are stronger in one direction than the other. They are used in punch presses for adjusting the position of the ram because they experience heavy impact forces as part of their design.
This kind of thread actually is called saw tooth tread, it is used when a thread has to withstand high force but only in one direction. You often see this kind of threads on excavators that go only one ore two floors up and down. The sytem is nice cause you dont really need any sort of emergensy break cause threads are so unlikely to fail and most often there are two of them onne on each side.
The metal gunk on the lid is probably an indium seal.
The magnets are most probably colbalt samarium.
this was really great, for years i've been wanting to get myself a small self-contained crycocooler to liquify gasses so anything regarding them is always interesting.
The fact the rattling stopped when you put pressure on the piston seems to indicate it's designed to be under backpressure. Probably quite significant backpressure given it's tiny displacement.
LPFthings The threads and the ceramic sleeve give it away. I don't think this is designed to work unless under very high pressure.
Pity the second sticker was removed, i bet it had info on it.
The outer channel of the coaxial tubing would normally be under vacuum. The purpose is to prevent/reduce heat loss through the tube.
It is under extremely high pressure.
That is not the hot end. The system is basically a compressor driver for a displacer piston moving in the remote cold head. This is an older split Stirling (not Sterling) cycle unit. Both cooling and heat rejection happens on the remote cold head. This is a push pull pump that feeds the cold head with necessary oscillations where the Stirling magic happens. Usually charged with helium or CO2 and at a very high PSI not vacuum.
I really enjoyed this video. There is so much beauty in many aspects inside machines.
I really enjoyed watching this video. thank you very much for producing such interesting rare content.
The coaxial tube is for insulation probably. I wonder if they draw the outer tube down to a partial vacuum.
Be carefull with the ceramic it might Be Beryllium oxide, nice teardown!
I think the threads are shaped like they are to handle high pressure. their profile means that its a flat pushing on a flat when the cap is under pressure from inside.
What a cool way to beat the welded construction. I think I'd be really nervous with something with that much uneven weight spinning on a lathe!
Very awesome teardown! sadly I saw nothing to help you date it or anything, but man it's sure neat! My guess is due to the low volume these were likely made in, and the insane amounts of money these had to cost, we probably won't find out specifics until someone who worked with one of these specific units sees your video. My google searches have come up generally fruitless, but I may continue anyway.
I think my 9 yr old has been watching your channel....Now i know why he wants to make a youtube channel called "TeslaToo"
I can't believe I just found this channel! Great stuff, subscribed!
threads like that are used in applications that need to be gas tight without contamination from a sealant. They are only good one or two times because the thread profiles of the screw and nut don't match. They wedge the two pieces together and the metal distorts. These aren't designed for aluminum. That may be why they needed to weld it.
This is awesome. Looks like a really well made piece of kit, albeit made only to last a set of brushes. It's almost as if 2 different companies made it!
at a quick glance i would say this thing is from some kind of thermal camera system, perhaps military?
The coaxial tube is possibly used for insulation reasons. Cryogenic fluids are (of course) very cold. Maybe the tube was vacuumized to prevent thermal loss.
Behold, The 2 by 4 of science! I'll bet the big flywheel is there to even out the running speed. The motor could run the piston on it's own but there would probably be a big variation in speed on the compression stroke vs the expansion stroke without it.
thanks for the tear a parts. neat technology is always cool to see how it works. thanks for your work.
i am excited that i saw this.. Looks like it is very well designed and high quality..
the flywheel is to keepa constant speed and more torque to get the compression stroke, it's easyer on the motor. the motor and bearing sealings and lube are built to operate at extremely low temps.
That was interesting, something you don't come by every day :)
5:17 Someone who designed this is screaming at the moment "Nooo, you fool. You are breaking the o-ring groove!!
Finally, a teardown channel that doesn't have an australian or british accent but rather a beautiful Canadian accent!
The piston sleeve is ceramic for heat possibly, and perhaps in case of failure, steel sleeve needs lube too right?
The flywheel is probably to smooth out the high torque load as the piston approaches TDC so that way the crank spins at a more constant speed rather than slowing down and speeding up every rotation
It was probably a cryo compressor for a satellite or something like that which would never have been serviceable anyway
It was built to hold as long it was humanly possible and this was what they could come up with in those days. It was still not that long time due to fex carbon brushes and what not in comparison to todays crycooler in similar build that of course use brushless motors and other things that doesnt contaminate near as much and thus have a much longer life length.
Interesting teardown. And good use of the lathe!
I love the sound it makes
Cryocollers are stirling engines guess this was too. The interesting thing in stirling engines is it can work in reverse. Actually reverse means cooling using power, normal mode converts heat difference to power. So you could use a cryocooler as a generator if the motor inside can work as a generator.
my guess is that the sawtooth threads is allowing radial movements. that makes sure the lid settles on the tapers and not the threads.
6:06 its for thermal insulation like thermos
assuming proper lubrication (removed for disposal because of toxicity) this motor and its brushes would last 30+ years before service or replacement, ive seen cases where brushed motors outlast brushless ones simply because of high end lubricant and lube designed brushes, now this unit was either removed because they switched to brushless or because it was at the end of its service life, because the lubricant would likely be flushed with the brush material we can presume that the black brush material in the end was from you and your friend running it, if it was at the end of its life and they went with brushed again that would be because of the simple startup and high start torque without drive circuitry, depending on the use this may have been only used to keep the cold on wile the power was out in large cryo systems, i.e its easier to run a dc load than to convert to ac or 3 phase ac, no driver required, and with most dc motors if they fault under normal conditions you increase the amperage and take note that that motor needs replacement as soon as regular power is returned either with a fuse that is then upgraded or a controller that reads current and activates a light to indicate failure
Great job, thanks.
I would expect the inner tube to protect the outer tube from collapsing when bent.
I was expecting that coaxial tube to connect in some way to the 2 holes in the internal plate, fridges often have a coaxial tube, especially the absorbtion fridge circuit, i was guessing the outer to be low pressure side, with the inner as high pressure. actually, i would guess the part that the pipe connects to has the valves for flow direction.
must be an extremely high pressure pump with that little displacement.
Yeah based on the size of that motor ill bet that pump can create some pretty extreme pressure.
One thing I notice, there is a strange buzzing noise being picked up by your camera's microphone in the video. It is more noticeable when the mic is close up the device, even more noticeable when you touch the lamp at 6:36 . The noise changes as you move around.
It does matter because these kinds of noises cause me a nightmare.
But I can't stop watching your awesome vids!
I remember Ben Krasnow talking about some metal gasket material like that
called a buttress thread on the cap, indium or graphite seal there.
isn't the other end of this unit a displacer/re-generator assembly?
a such quality part is surely not for civilian use
Maybe they used the coaxial tube just to protect the fragile inner tube.
Chris W Or perhaps for insulating the inner tube?
dumle29 I would guess that the space between the tubes was evacuated for thermal isolation as only the inner tube actually connected to the piston cylinder.
randacnam7321 Yea it'd seem logical at the possibly extremely low temperatures.
dumle29 จตคตจจ ววื
จันทร์ทอง ศรีแก้ว what?
that welding really looks like EB welded.
Too bad we didn t get to see the rest of the system.
thx
Paper weight, come on tesla500....... that is one nice dc motor. Use some of your skills and use it in a build that requires a strong drive motor, perhaps get rid of the concentric drive and mount a spocket, pinion or pulley. Its just way too nice to use as a paper weight. If you do fabricate an idea be sure to post a video of your build. Cheers!
bro he owns the most awesome paper weight in the world, how dare you try and take that from him .
Any information on the piston seal or ring?
once you assemble again, will it work or it need to refill with Helium?
Where are you from??
Pk se taalouk hai
cryo engine pr kabhi working ki hai ??
very interesting....this was my curiosity too....
Careful wire
I would love to design an open source cryogenic cooler
I looked at this video sitting in a comfortable soft sofa, having a nice warm felt over my legs and some good food in front of me and then just enjoy this movie.
If they are designing it to not be serviceable, then those units would likely not sell unless they price them in the $40-50 range at the highest when they are brand new.
Razor2048 I believe the motor was designed separately from the enclosure. You don't bother with screw adjustment on brushes when you purposely design it to never be opened.
However, there's another possibility. Perhaps the threads were not enough and they decided that a welding was needed on top of the special thread.
Razor2048 Try adding a couple of zeroes to that price and you'll be more in the ballpark.
+Razor2048 Bruh the materials are worth nearly that.
The materials are worth FAR MORE than 50 dollars. This little device is easily many thousands of dollars new. when you exit retail and enter into commercial use. The price tag doesn't matter. The end user NEEDS it. There is no competition. The part must be designed, engineered and lastly fabricated. The costs of all of those things need to be rolled into the cost of the final product. If that pump costs less than 12k id be flat out amazed. If it cost 120k i would be not that surprised.
threads and the taper act like a compression fitting , notice the rubber gasket....
it also acts against the force... think pressurized chamber
what camera do you use for your videos? They look very nice.
+atmel nerd Panasonic TM700
+tesla500 I guess stumbled over something regarding this device. It seems to be a kind of pro grade vacuum pump
At 502 to 7 this guy has one of the highest ratings of any video I've seen. Only chemplayer has had a higher rating....,
Why did you destroy it.
The gasketresidue is probably the remains of a graphite gasket.
I am a bit late, but this looks very much like a "pulse tube cooler"-compressor ;)
looked like a spiral lock thread
Plz plz plz show Me this piston
the gasket was probably made of Indium metal
laurdy I agree. Indium seals are typically used in cryo applications because of their malleability at very low temperatures. Helium will find the most minute of leaks and is used for leak testing in hermetically sealed systems because of this.
this thing is probly 50 years old lol
Sound familiar?
th-cam.com/video/NNO8SxvV7ok/w-d-xo.html
AC power in that lamp hahaha
BRO whats it like to be the shit ?