Vacuum wax Injecting machine ?

[asrock70]

Does anyone have experience or don't know how exactly something like this works?
It's actually very simple. If you have turned on vacuuming and automatic mod.
When we press the mold to the nozzle, air is sucked out of the mold for a set time, for example 3s, then again after a set time, molten wax is injected into the mold under pressure.
Technical:
pressurizable container into which wax is poured.
the container has heating of approx. 400W with an adjustable temperature up to 100C
a pipe with a nozzle leads from the tank and it has a separate heater with an adjustable temperature
wax pressure is ensured by air pressure, time by a timer and an air solenoid valve
then, everything is clear and easy to implement
The question is how is vacuuming handled?
Like pressurizing? That is Do I create a vacuum in the container and suck the air out of the mold through the wax in the container?
The second air valve is connected to the vacuum source and for a set time it sucks the air out of the pressure vessel and through the wax and out of the mold?
It seems logical and easy to implement. The negative pressure is obtained from the pressure on the venturi tube. Yes, we have to overcome the wax pressure, but the 20cm column will only be 0.02 bar .
However, any other solution requires at least a non-return valve so that the wax does not get into the suction chamber when pushing it, and I can't really imagine that.
In short, if anyone knows or has a guess, you can save me time and futile attempts

 

[carpenter]

One picture worth a thousand words.
The inner small container is the vacuum reservoir.
The wax is in that big container
Drain valves for wax and vacuum on the left.

 

[asrock70]

Thank you for the information.
So, two separate branches.
The important thing, the wax is under constant pressure and the electromagnetic valve switches on the wax (liquid). The valve must operate at a temperature of 65-85C
I am thinking about how to implement such a valve.
Maybe like a spray gun, just control the needle with a coil.

 

[carpenter]

Most often, the injection block looks like this
a solenoid opens wax on one side and a vacuum on the other side
schematically, see the second picture
yes, the vacuum also sucks some of the wax from the common part of the nozzle
from this point of view it is better, but mechanically more complicated, see the third picture

--- Updated Apr 5, 2023 ---

I will add more.
When using classic industrial valves, you are looking for something that has a sufficiently large hole, can withstand temperatures up to 90C and can withstand oils and organic acids
For example Valve 2V025, orifice 2.,5mm, as seal maerial VITON,
the heating could be released with GBR-618 heating resistor 20W.