Passive locking device and double-locking structure for railway vehicle door system

The invention discloses a passive locking device for a railway vehicle door system and a double-locking structure. The passive locking device comprises a sliding block guide rail, and a lead screw is installed on the outer side of the sliding block guide rail; the screw rod is sleeved with a first nut assembly, the first nut assembly comprises a rolling pin, a sliding block, a nut sleeve and a nut, and the nut is made of a non-metal material; the inner wall of the nut is matched with the lead screw. The outer wall of the nut is fixedly sleeved with a nut sleeve. A sliding block is arranged at one end of the nut sleeve, and a rolling pin is arranged at the other end of the nut sleeve; a locking pin limiting stop block is arranged above the sliding block guide rail; the sliding block check block is installed on the locking section, the sliding block guide rail is provided with an opening in the locking section, when the sliding block moves to the locking section, the sliding block retreats from the opening, the