Movable side wall and opening/closing mechanism for railroad boxcars

A railroad boxcar with a movable side wall, comprising:

• a side wall assembly (1) comprising a side wall (1.1), an upper abutment assembly (1.3) configured to support and slide the side wall (1.1) and a lower abutment assembly (1.4) configured to support and slide the side wall (1.1), wherein the upper abutment assembly (1.3) further comprises an upper abutment (1.3.1), an upper roller (1.3.2) and a slide rail (1.3.3), the lower abutment assembly (1.4) further comprises a lower abutment (1.4.1) and a lower roller (1.4.2);
• an end portion opening/closing mechanism (2) comprising a handle assembly (2.1) being fixed to an end wall of the railroad boxcar and being capable of freely rotate up and down for the opening and closing states of the handle assembly (2.1);
• a pivot rod assembly (3) configured to lock the side wall assembly (1);
• an upper transmission shaft assembly (5) configured to support and shift the side wall assembly (1), the upper transmission shaft assembly (5) comprising:
• an upper transmission shaft (5.1) and an upper transmission shaft shifting fork (5.3) configured to match with the upper roller (1.3.2);
• a lower transmission shaft assembly (6) configured to support and shift the side wall assembly (1), the lower transmission shaft assembly (6) comprising a lower transmission shaft (6.1) and a lower transmission shaft shifting wheel (6.3);
• an upper track assembly (7) comprising an upper track (7.1);
• a lower track assembly (8) comprising a lower track (8.1), and
• a side door central pressing device (4),
• wherein a rotation of the handle assembly (2.1) of the end portion opening/closing mechanism (2) is configured to
• drive upper transmission shaft (5.1) and the lower transmission shaft (6.1) to rotate by the connecting rods of the end portion opening/closing mechanism (2);
• drive, by the upper transmission shaft shifting fork (5.3) and the lower transmission shaft shifting wheel (6.3), the side wall assembly (1) to deviate as a whole through:
• dropping the upper roller (1.3.2) on the side wall assembly (1) onto the upper track (7.1), and the lower roller (1.4.2) on the side wall assembly (1) onto the lower track (8.1);
• and
• enabling the side wall assembly (1) to slide along the upper track (7.1) and the lower track (8.1).