Modifiche

The breather tube is inserted in the feeder and kept in a central position with respect to the body of the pen, which normally acts as a tank. During the compression phase, the air in the pen comes out of the blowhole, from which, due to the depression created, the ink that ends up in the tank is loaded; the presence of the blowhole means that the ink loaded is not expelled in the subsequent compression phases, until the entire tank is filled up to the level of the blowhole.

The breather tube is inserted in the feeder and kept in a central position with respect to the body of the pen, which normally acts as a tank. During the compression phase, the air in the pen comes out of the blowhole, from which, due to the depression created, the ink that ends up in the tank is loaded; the presence of the blowhole means that the ink loaded is not expelled in the subsequent compression phases, until the entire tank is filled up to the level of the blowhole.

La presenza dello sfiatatoio in alcune realizzazioni ha inoltre un secondo effetto positivo perché consente di equilibrare immediatamente la pressione dell'aria interna al corpo della penna con quella dell'aria esterna, dato che in questo caso lo sfiatatoio fornisce una via di comunicazione fra interno ed esterno, si evitano così i vari problemi di fuoriuscita dell'inchiostro in caso di sbalzi di pressione.  

The presence of the breather tube in some realizations also has a second positive effect because it allows to immediately balance the pressure of the air inside the pen body with that of the external air, since in this case the breather provides a way of communication between inside and outside, thus avoiding the various problems of leakage of the ink in case of pressure changes.  

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