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Electronics => Projects, Designs, and Technical Stuff => Topic started by: ali_asadzadeh on June 13, 2017, 10:37:18 am

Title: How does this sealing machine works?
Post by: ali_asadzadeh on June 13, 2017, 10:37:18 am
Hi,
My friend send me this puppy for repair, I just wanted to know what's the principle behind it, I can see it has a full-bridge MOSFET that is tied to a mysterious big chunky inductor that's connected to this huge heat sink. which I think can do the welding with the magnetic field.

any Ideas are welcome!

Title: Re: How does this sealing machine works?
Post by: ali_asadzadeh on June 13, 2017, 11:02:04 am
The main controller part is SG3526 and the MOSFETs are APT55M50JFLL  ,and two  IR2113 MOSFET  drivers, you can see the big self and caps there, I think they have used the litz wire for them!  there is nothing special with this puppy, everything is jelly bean parts.
Title: Re: How does this sealing machine works?
Post by: P90 on June 13, 2017, 11:06:38 am
looks like it's an inductive sealing unit. An inductive coil creating a varying magnetic field heats some sort of aluminium layer in the sealing material and melts it to the container.
Title: Re: How does this sealing machine works?
Post by: ali_asadzadeh on June 13, 2017, 11:57:37 am
Thanks for the info, would you explain more? how is the SG3526  working? do you have any tutorial or app note about it
Title: Re: How does this sealing machine works?
Post by: macona on June 14, 2017, 05:31:43 am
Yep, its an inductive sealing unit, it heats up the metal foil in the package which melts the plastic when it is squished in the sealing jaws.

The SG3526 is a pretty generic PWM chip, it drives the gates of the mosfets in a H-bridge which turns the DC coming in to AC, basically a high frequency inverter. The rectangular blue caps are part of the tank circuit.
Title: Re: How does this sealing machine works?
Post by: ali_asadzadeh on June 14, 2017, 12:03:46 pm
Quote
Yep, its an inductive sealing unit, it heats up the metal foil in the package which melts the plastic when it is squished in the sealing jaws.

The SG3526 is a pretty generic PWM chip, it drives the gates of the mosfets in a H-bridge which turns the DC coming in to AC, basically a high frequency inverter. The rectangular blue caps are part of the tank circuit.
Thanks Macona, Do you have a simplified circuit diagram? thanks in advance