Mystery Item thread.... What am i?

[Darkwood]

This is out of an old Russian lathe it has 4 contacts on it 2 x NC and 2 x NO it has a coil and on top it has a sealed oil filled reservoir.
What is its function!

Spoiler alert!!! Answer in post 9!!!

 

[pennywise]

Potato peeler

 

[Silly Sausage]

Я понятия не имею!

 

[Darkwood]

Yes penny often find a Russian lathe in your local chippy

- - - Updated - - -

Я понятия не имею!

Close but no cigar..... i think?

 

[PEG]

It's very pretty,i could do with it in front of me......Is the oil filled resevoir affording cooling to the coil via structure? I have seen many devices fitted to old eastern european gear and they do not tend to have anything which is frilly or non-essential.

 

[Darkwood]

No the oil reservoir provides a function and can be adjusted to suit its a mechanical operation and has nothing to do with cooling.
We can of course establish this is a relay of some nature but it affords an extra function when the coil is de-energised.

 

[Marvo]

Motor reverse switch perhaps?

 

[DPG]

Hydraulicaly damped overload relay? Daz

 

[Darkwood]

Il let the cat out of the preverbial bag so to speak as any mor clues would give it away...

Its a timer relay with true off delay..... When the coil is energised it pushers a lever onto a micro switch to change the relay states, when the coil is de-energised the lever stays in position held by the suction of the oil reservoir which slowly releases in accordance with the speed at which the oil pressure is released (adjustable with a screw)

Its particular function on the lathe was to energise the Electromagnetic Brake after the stop button has been hit and the off delay is adjustable and requires no permanent power to relay.... The brake is DC and the control is 110v AC so a fault or loss of AC control would hopefully still allow the braking to function safely.

It oil reservoir works the same way the push button timer switches do normally used on stairwell lighting in flats.

Modern technology version although can't see this doing the 50yrs service the old one did.

 

[Darkwood]

Me only been in the working life 25yrs sometimes seeing these old devices throws a curve ball at me as firstly before you can fault a machine you need to recognise what the hell some off the gear is .... with no wiring plans or any clues on the unit it took a good hour to work out its function and where its role was in the machine ..... once i sourced a modern replacement it took 10mins to replace..... Everydays a school day even for my experienced yrs....

Anybody got any old relics on their shelf that may fall within the nature of this thread then feel free to post them up for us to try and identify.

 

[Clive P]

Hi,

The wife hates her picture being taken.

Regards.

 

[Lucien Nunes]

Nice bit of traditional Soviet technology there Dark, what actually failed on it? Most of their industrial stuff seems to go on almost for ever.

While we're on machine tools I'll offer one from our own workshop. It's a 1957 Swiss-made Dixi jig-boring machine driven by its original Ward-Leonard variable voltage DC speed controller. The operator adjusts the speed over a wide range with a small dial on the control panel, it is reversible and has an inching mode. The controller feeds the drive motor with 0-320V 0-65A DC from the motor-generator set which is separate to the machine. The mystery item is part of this system, located inside the electrical cubicle on the machine. It has a laminated steel core with (IIRC) five windings on it, however the answer is not 'transformer'.

Lucien

 

[DPG]

Choke? Daz

 

[Lucien Nunes]

Nope, not a choke. There is something a bit choke-ish and a bit transformer-ish about the way it works, yet it is neither a transformer nor a choke.

 

[Darkwood]

Nice bit of traditional Soviet technology there Dark, what actually failed on it? Most of their industrial stuff seems to go on almost for ever.

50 plus years of a early hard mould plastic plunger eventually wears it away, its possible to probably do a makeshift repair but as its fuctio is braking related its best to replace for sake of £50 ....Electrically still sound.

 

[DPG]

I'll have another think. Looks like a selenium rectifier to the right of it though. Daz

 

[Darkwood]

As its multi-tapped windings i assume this is maybe used for selection of speed in some way ...as noted theirs a rectifier on the right, adjustable resistors above .... but without seeing what is used to select speed its a wild guess.

Is the speed selected by a multi position switch or by a pot'

Yep! il say its the old fashio speed control..... just pre-set speeds using the adjustable resistor rods.... ???

 

[DPG]

I can only think of an auto-transformer or a multi-tapped choke. Come on, give us a clue Daz

 

[Lucien Nunes]

The speed is controlled by a pot. AFAIK none of the windings is tapped, they are just five separate windings. The selenium rectifiers are related to the mystery item and they are the only semiconductors in the speed controller.

 

[Darkwood]

AC in transformed for rectifying by the plates?....basically an all in one AC-DC power unit?

 

[Lucien Nunes]

Nope, the power supply transformer is to the right of the DIN terminals. The windings on the mystery device connect to the speed control pot, the main motor, a DC supply, the AC control supply, and one field winding of the cross-field servo-generator on the M-G set via the rectifier.

 

[Robotstar5]

I thought the first pic was an overload unit as one of my jobs as an apprentice (in the 70's) was to go round checking/topping up the dashpots on the ancient Allen West contactors.

 

[stranded]

Thats a cracker bit of kit there. Old gear is cracker. Us, being men, like taking things apart...and seeing what some old things like leccy gear is really interesting, even if it is confusing. A good example is Microwaves.Years ago, built with a nice high voltage transformer in them , made in england,now, replaced by "inverter technology" crap , made in china, and the old microwave will outlive the new one by 30 years. Its interesting to see how things have developed and moved on though, and a small lightweight circuit board has the same capabilities of a heavy, copper wound transformer.

 

[Lucien Nunes]

Well it's lasted 56 years so far, I've tickled up a few relay and contactor contacts in the last dozen years, changed the brushes and one resistor and that's about all. The rectifiers were replaced in the 1970s. When the machine moved premises a few years ago I did think about putting on a VFD to save having to install the Ward-Leonard set but as it works perfectly it seemed a shame not to use it.

Final clue for the evening - see the pic of the M-G set on which I have labelled the four units. The cross-field machine amplifies the servo demand signal but it's not sensitive enough to give good closed-loop control from the pot output and a small feedback signal. That's where our mystery device comes in.

 

[Darkwood]

Signal amp' or some kind of damper to stabilise speed then if your speed ref is't accurate enough the motor can cycle up and down with speed chasing its self ....