Is the vacuum pump pen an eternal patent?

Yongsheng 60 1 and Yongsheng 60 1A are recent new products. In fact, the brand of eternal life has long gone bankrupt and was bought by heroes. Now most of these eternal life pens are brand products.

The inking structure of the two pens is the same, but the difference is that 60 1 is the small tip, and 60 1A is the big tip, also called the victory tip.

This kind of pressing vacuum ink delivery is Parker's invention. "Golden Arrow" pen originally used in 1932 publication. This series of pens was renamed as Parker vacuum filling machine on 1933, and finally named as "vacuum series". It is said that a pen without ink sac was invented that year. However, when Xi Feili released his own vacuum ink-feeding pen on 1934, he pointed out that Parker's vacuum ink-feeding did not use ink sac, but did not use ink sac as ink sac, because the ink sac in the pen has the same function as the human diaphragm, and some people called it "diaphragm sac".