WING OPENING/CLOSING DEVICE FOR TRUCKS OR THE LIKE

A wing door opening/closing apparatus including a link mechanism and a spring for swinging up a wing door 1. This wing door opening/closing apparatus is made up by plural wing door opening/closing devices A and B. The disparity of the moments generated by one wing door opening/closing device A in the plural wing door opening/closing devices A and B is compensated by a moment generated by the other wing door opening/closing device B.