Double-blank detecting apparatus for use in destacker

A double-blank detecting apparatus for use in a destacker, comprising a plurality of rows of fixtures, each of said rows of fixtures being parallel with the direction of conveyance of blanks and including a plurality of fixtures, each of said fixtures being mounted on the frame of the destacker in such a manner that it can be moved up and down by means of a lift cylinder;

• attractor means mounted on said fixtures, respectively;
• and a plurality of rows of conveyor means having attracting function extending in parallel relationship with one another and with the direction of conveyance of blanks and mounted between said rows of fixtures, and wherein each of said fixtures in at least any one of said rows has a contact type sensor mounted thereon in such a manner that it can be moved up and down freely relative to said blanks having been attracted by said attractor means, wherein each of said fixtures in connected at its intermediate portion with said lift cylinder, each of said fixtures having an approximately L-shaped body, one end of said body having a downwardly extending attractor means fixedly secured thereto, the other end of said body having a sliding rod which is fixedly secured thereto and which is inserted in a guide so as to slidably move up and down;
• and an approximately V-shaped plate, connected at the base portion to the lower surface of said body, said plate having a piston-cylinder unit which is fixedly secured to one end thereof and which has a piston rod adapted to slidably move up and down through said plate, said plate having a downwardly extending type sensor is connected through a mounting block to said piston rod, and said mounting block is mounted so as to be moved up and down freely by said piston-cylinder unit through a guide rod.