concertina fold

基本解释

Parallel folding can be operated for two times with the buckle plate. Its mode of folding includes parallel fold, concertina fold and letter fold.
在采用栅栏折页时可进行四次平行折页，折页方式为平行折、风琴折、包芯折；
www.xianghan-machine.com
Parallel folding can be operated for two times with the buckle plates. Its mode of folding includes parallel fold, concertina fold and letter fold.
在采用栅栏折页时可进行两次平行折页，折页方式为平行折、风琴折、包芯折；
www.xianghan-machine.com

It was supposed to be a convertible, but the concertina metal bits that supported the canvas top were too rusted to fold back.
NEWYORKER: Hand on the Shoulder