Pick and Place Machine TVM802A / TVM802B

[rx8pilot]

I just have a cutoff switch that I can set to turn off at just under 29in and turn on when it gets to around 22in. It also has a continuous switch but I have never needed it. I use the same vac system for my various pickup tools and to de-gas silicone and polyurethane for over molding cables.

[harry4516]

@rx8pilot , @harry4516 , @ar_systems

Would this vacuum pump do the job? They go for US$100 shipping included..

https://www.aliexpress.com/item/FY-1H-N-150W-1L-Lightweight-portable-air-compressor-vacuum-air-pump-for-vacuum-LCD-separator/32736004424.html?spm=2114.13010208.99999999.304.2cWg7z

Also do you need some kind of regulator to limit the vacuum or will the air valves(solenoids) be okay without it?

this is the same pump as mine. It works ok.
It blows out a fog of oil, you need to separate it from the PnP machine.
I have connected a tube which goes out of the window.
Maybe an oil free pump is a better choice.

@rx8pilot: what size is your storage tank ?

[rx8pilot]

I think it is about 10 gallons.

[uncle_bob]

Hi

I suspect that a two stage oil pump is a bit overkill

Bob

sure, this is overkill,
previously I had a membrane pump of the same size. It had two problems. The engine got very hot after a minute and it only started at normal pressure, not if vac was already there.
The new pump costs about $250 and stays cold even after 10 minutes.

Hi

In this application the difference in pump down between a single stage and a double stage pump is likely to be unimportant. They both will get past 29" with no trouble at all. The single stage (possibly of questionable quality) can be had for < $80 in the same ~ 3 to 4 CFM pumping capacity.

Bob

[protoneer]

It blows out a fog of oil, you need to separate it from the PnP machine.
I have connected a tube which goes out of the window.
Maybe an oil free pump is a better choice.

Could it be that you over filled the oil?

I am tinkering with the idea of adding a pressure sensor. Something like this: http://www.mouser.com/ds/2/302/MPXV7002-783439.pdf

Just to get a sense of that the machine is doing.

The more I think about it, if I can get the machine to report an error with the smaller components it would save me plenty of time baby sitting the machine. (It works great on bigger components to the point that I can work on other stuff while it does its job and when there is an issue it just stops)

[protoneer]

Does anyone know how many pressure sensors the machine have and where they are located?

(I have about 12 hours of work booked for the machine before I can poke around under the hood)

[uncle_bob]

It blows out a fog of oil, you need to separate it from the PnP machine.
I have connected a tube which goes out of the window.
Maybe an oil free pump is a better choice.

Could it be that you over filled the oil?

I am tinkering with the idea of adding a pressure sensor. Something like this: http://www.mouser.com/ds/2/302/MPXV7002-783439.pdf

Just to get a sense of that the machine is doing.

The more I think about it, if I can get the machine to report an error with the smaller components it would save me plenty of time baby sitting the machine. (It works great on bigger components to the point that I can work on other stuff while it does its job and when there is an issue it just stops)

Hi

*IF* you want the machine to report a very small part missing (with a pressure sensor)  ... you need a low volume vacuum pump.

*IF* you want the machine to pick up and hold a very small part ... you need a high volume vacuum pump.

Essentially you have two requirements pointing you in opposite directions. As the nozzle gets smaller and smaller, the flow through that nozzle (when open) gets less and less. With a high enough volume pump, the entire pressure drop would be at the nozzle (for a really small nozzle).

An alternative is to detect flow rather than pressure. You can also check for the part with a camera.

Bob

[harry4516]

...
Essentially you have two requirements pointing you in opposite directions. As the nozzle gets smaller and smaller, the flow through that nozzle (when open) gets less and less. With a high enough volume pump, the entire pressure drop would be at the nozzle (for a really small nozzle).
...

exactly, thats the problem.

The yuki-503 nozzle (which is the right nozzle for 0603 parts) works with pressure sensor and the original vac pump very well. It detects if a part is missing.

With my new strong vac pump pressure detection does not work any more, so I use the yuki 504 with a larger hole. I placed a few boards and it works well with 0603 parts. This is a big advantage because the TVM802 has two nozzles only.
Previously I used the 503 and the 505, now the 504 and the 505. The better vac let me use a broader range of different components.
Also, I had big problems with SOT23 before (jumping and rotating on the nozzle while travelling), this problem is solved with the better vac.

Harry

[protoneer]

The yuki-503 nozzle (which is the right nozzle for 0603 parts) works with pressure sensor and the original vac pump very well. It detects if a part is missing.

With my new strong vac pump pressure detection does not work any more, so I use the yuki 504 with a larger hole. I placed a few boards and it works well with 0603 parts. This is a big advantage because the TVM802 has two nozzles only.
Previously I used the 503 and the 505, now the 504 and the 505. The better vac let me use a broader range of different components.
Also, I had big problems with SOT23 before (jumping and rotating on the nozzle while travelling), this problem is solved with the better vac.

Harry

Thanks for pointing out the high vs low flow.

I have ordered the stronger Vacuum pump so that will solve one issue. My TVM802A does not have Juki Nozzles but I have seen a few adapters that might fit. Will give that a go.

Out of interest @harry4516 , what size Juki Nozzle would you use for 5050 led's?

[ar__systems]

Does anyone know how many pressure sensors the machine have and where they are located?

(I have about 12 hours of work booked for the machine before I can poke around under the hood)

It has two pressure sensor on the bottom side of the circuit board that is screwed to the top of the block.

Both are semiconductor transducers, however schematics is extremely basic. There is no calibration of the sensors, and there is no threshold adjustment.

On my machine I don't have a problem with it not seeing 0603 missing. I think on my machine it is too sensitive even with external pump, and dumps parts that look like picked up relatively ok. 

[ar__systems]

Hi

*IF* you want the machine to report a very small part missing (with a pressure sensor)  ... you need a low volume vacuum pump.

[/quote]
That's not true. You just need a pressure sensor with adjustable threshold.

[uncle_bob]

Hi

*IF* you want the machine to report a very small part missing (with a pressure sensor)  ... you need a low volume vacuum pump.

That's not true. You just need a pressure sensor with adjustable threshold.
[/quote]

Hi

As long as you have a pressure sensor that has a perfectly stable threshold, an very small hysteresis, and a set point that will adjust to very close to 29.x" of vacuum .... yes that is correct. With practical sensors, you do indeed have a compromise for very small nozzles.

Bob

[Koen]

Hello, what do you guys recommend to make sure the nozzle picked a part at our DIY level ? Vision, a particular pressure sensor, lasers ? Thank you !

[mikeselectricstuff]

Vision is the best value for money, as it gives you both alignment and mis-pick detection. Any pick & place without vision is just a  toy.

[SPY GUY]

IMHO it seems that the same thing is required.
Both based on taking an analog output from a sensor such as listed and converted into a digital output based on comparison input from a user adjustabe threshold value. 
1) The softwares digital pressure sensors detect input.
2) The reservoir pressure that can control the internal or external Vacumn pump(s).

This can easily be achieved via a very basic micro controller with A to D's and coffee break coding, or even with just basic comparitors.
Not so much an analog person myself.

You could even get more fuity with a micro that has TCP/IP input that then applies different vacumn values for 1) based on watching co ordinates.

just my humble 2C's worth

 

 

[huebsch]

Folks!
I reported severe problems with the TVM802A powered by W10 about 2 weeks ago. Based on recommendations in this forum I installed a new PC with plain W7 patched it up to the most recent level and started testing. The PC is a 2GB ATOM box which just went out of use. The program does not need much PC power. To make a long story (calibration) short: it works with almost no problems. I have some error messages when I accidentially klick outside the controller program. This does not cause any wrong movements which I had before. I ordered new nozzles as the current ones might got damaged - or I'm not quite sure about them. Sometimes they drop components even speed 50% speed. I do not want to use vision on 1208 resistors.

It's really worth the time to invest time on calibration. Unfortunately I'm still trying to find out what some of the values in the software mean. We should compile some advices on this to help others.

Next upgrade is a touch screen. I used a mouse and later a touchpad keyboard to save space. But when I'm at the machine it might be easier to touch the screen. Especially some confirmation windows are quite annoying. I still have the problem, to stop the machine with the keys on it. So I frequently change back to the computer -> my idea to connect a touch screen.

Arnold

[harry4516]

...Sometimes they drop components even speed 50% speed. I do not want to use vision on 1208 resistors...

I had the same problem, it was caused by the poor vacuum (in combination with the level of vibrations). I solved that with an external vac pump.

regarding 1206... after some experience you will use vision for all components. Take more time but need less manual corrections.

[tmf]

After I align with 2 fiducials I ask the machine to go to say (0,0) I then make note of it, I then move 6.000 inch to the right and it moves 6.014.... I have verified this time and time again, then a 6.000" move in Y and its off approx 0.014" again...... + 0.3 to 0.4mm both axis

I have also tried to not use the fiducials, do not enable them.... and still the same thing....

The 2 point I am moving between on the PCB are exactly correct!

I think the pixels per inch calibration must be off, how do you calibrate this??
Or???

Thanks.

Richard.

[thommo]

TFM,

I'd contact the guys at QiHe.

A mate of mine who owns a TVM920 had the same issue.

The gave him an updated version of the App. which rectified it issue immediately.

Good luck - Peter

PS: perhaps one of the other guys may have a later/est version they could send you.
Don't know about the 802, but the 920 has provision to calibrate this and reconfigure.

[harry4516]

my software for the TVM802 is: Version 2.12

[huebsch]

Hello!
My SW Version of TVM802 is 2.23Beta2. If somebody wants to have it I can put it on a public space.
Arnold

Sorry folks there was a typo in the version I modified the posting

[tmf]

That would be nice.... mine is 2.23beta2 and they sent me the "solution" but when you goto the screen that has the config its missing! So they are probably talking about a newer version.... (you did mean 2.32beta2 or did you mix up 2 characters)

Please let me know when you upload.. looking forward to it!

Thanks!

[tmf]

china just sent me 2.27 and it wont even home! 

RichardS

[huebsch]

china just sent me 2.27 and it wont even home! 

No good news. But how have you got access to the update?
-AH-

[harry4516]

instead of mailing bad updates QiHE should release the source code.
The community could fix the problems in a very short time.

I think thommo from Australia is in close contact with these people. Could you talk about it ?