Metal sheet bending device with rotation inhibiting function

A metal sheet bending apparatus comprising:

• a support having first and second concave portions each having a section of a semicircular shape, a groove being formed between the first and second concave portions;
• first and second lower bar molds each having a semicircular shaped section along a surface perpendicular to a longitudinal direction of the first and second lower bar molds, the first and second lower bar molds having metal contact surfaces, respectively and being rotatably provided in the first and second concave portions, respectively such that the semicircular shaped section of each of the first and second lower bar molds fits in the semicircular shape of each of the first and second concave portions, the first and second lower bar molds having recessed portions on the metal contact surfaces along the longitudinal direction at a contact portion between the first and second lower bar molds;
• first and second pull-up rods having end portions, respectively, the end portions being rotatably connected to the first and second lower bar molds, respectively;
• first and second stoppers provided to the support, the first and second pull-up rods passing through the first and second stoppers, respectively;
• first and second fixture attached to the first and second pull-up rods, respectively at an opposite side of the end portions with respect to the first and second stoppers;
• first push spring provided between the first stopper and the first fixture;
• second push spring provided between the second stopper and the second fixture;
• and
• an upper mold having a rounded tip and adapted to bend a metal sheet placed on the metal contact surfaces of the first and second lower bar molds by pressing the rounded tip against the metal sheet above the groove and further to bend the metal sheet to be a U-shape while the first and second lower bar molds rotate against spring force given by the first and second push springs such that the metal contact surfaces form a substantially V-shape.

A metal sheet bending apparatus comprising:

• a support having first and second concave portions each having a section of a semicircular shape, a groove being formed between the first and second concave portions;
• first and second lower bar molds each having a semicircular shaped section along a surface perpendicular to a longitudinal direction of the first and second lower bar molds, the first and second lower bar molds having metal contact surfaces, respectively and being rotatably provided in the first and second concave portions, respectively such that the semicircular shaped section of each of the first and second lower bar molds fits in the semicircular shape of each of the first and second concave portions, the first and second lower bar molds having recessed portions on the metal contact surfaces along the longitudinal direction at a contact portion between the first and second lower bar molds;
• first and second pull-up rods having end portions, respectively, the end portions being rotatably connected to the first and second lower bar molds, respectively;
• first and second stoppers provided to the support, the first and second pull-up rods passing through the first and second stoppers, respectively;
• first and second adjust screws attached to the first and second pull-up rods, respectively at an opposite side of the end portions with respect to the first and second stoppers;
• first push spring provided between the first stopper and the first adjust screw;
• second push spring provided between the second stopper and the second adjust screw, spring force given by the first and second push springs being adjusted by the first and second adjust screws;
• and
• an upper mold having a rounded tip and adapted to bend a metal sheet placed on the metal contact surfaces of the first and second lower bar molds by pressing the rounded tip against the metal sheet above the groove and further to bend the metal sheet to be a U-shape while the first and second lower bar molds rotate against spring force given by the first and second push springs such that the metal contact surfaces form a substantially V-shape.