If any toilet w/ double-siphon and a air tube link to water tank has been production?

[enchuan.lio]

Dear Sirs,

If any toilet w/ double-siphon and a air tube link to water tank has been production and which brand?
Could you kindly answer my question? Thanks a lot.

 

[Terry]

The closest was the Briggs Vacuity.

https://terrylove.com/forums/showth...-review-and-comments&highlight=briggs+vaCUTIY

Water in the tank, vacuum tank and bowl are at their maximum levels.
Water level in the lower passage permits venting of air into the drain line.

When flush lever is activated, tank water passes through the outlet into the bowl rim.
As water rushes into the bowl from the rim, water also passes down the trap, sealing the air vent

After a few seconds, tank is empty, valve is closed and refill begins.
At the same time, water discharges from the vacuum tank, creating a vacuum in the upper portion of the passage way.
This vacuum draws water from the bowl into the trapway.

After all water has passed through the rim, air is vacuumed into the trapway.
The vacuum tank refills, air is forced down the vacuum tube and into the lower passage.

https://terrylove.com/wc/briggs/vacuity_works.htm

 

[Sponsor]

 

[enchuan.lio]

Dear Terry,

I deeply appriciate your kindly help.

Best regards,
En Chuan

 

[Redwood]

Unfortunately the Briggs Vacuity wasn't very productive...
It was actually a pretty bad toilet...