Lid forming device

A lid forming device that forms a lid of a cardboard box using, out of a group of flaps having a cantilever structure and provided on edges of an opening of the cardboard box, a first flap in which a slit is formed and a second flap to be extended after being bent into a mountain shape, the lid forming device comprising:

• a first folding mechanism configured to fold the first flap in a direction in which the first flap closes the opening;
• a second folding mechanism configured to bend the second flap into a mountain shape and insert part of the second flap into the slit of the first flap while extending the second flap,
• wherein the second folding mechanism includes
• a first retaining unit configured to retain a first face of the second flap located between a free end of the second flap and a bend line set beforehand in the second flap and
• a second retaining unit configured to retain a second face of the second flap located between an anchored end of the second flap and the bend line;
• and
• the lid forming device further includes a control unit configured to control the second folding mechanism, wherein
• the second folding mechanism further includes
• a first drive unit configured to cause the second flap to pivot about the anchored end of the second face,
• a second drive unit configured to retain and release the first face and the second face of the second flap using the first retaining unit and the second retaining unit,
• a third drive unit configured to drive the first retaining unit and the second retaining unit until the relative angle between the first face and the second face of the second flap becomes a predetermined angle, and
• a measuring unit configured to measure, and output to the control unit, at least an operating time of the third drive unit, and
• the control unit is further configured to adjust an operation of the first drive unit and/or an operation of the second drive unit based on the operating time of the third drive unit.