| 摘要 |
PURPOSE:To make any plastic material uniformly bendable without occurrence of crack even if said material has a deformed section such as corrugated shape, by extending a plate of plastic material from one end of a base in the form of cantilever and pressing this extended part toward the end of said base by using a rotary bar rotatively driven in the rolling direction to bend said extended part. CONSTITUTION:Directly after a plastic material is extruded from a forming die, a rotary bar 1 rotatively driven in the rolling direction (shown by arrow P) is moved to press and bend a formed body 2 toward the end face 3 of the base, while the extruded part is in a cantilevered and extended state. In this case, because the rotary bar 1 is rotatively driven in the direction shown by arrow P, the extended piece 4 is bent by frictional force, being under the force to the direction shown by arrow M. Therefore, in the periphery of the bent portion of said plastic material, created by a simple bending, the material flowing is supplied due to the force caused by frictional force, so that the crack occurrence is prevented. Accordingly, when the rotary bar 1 goes down perfectly, a bent edge is formed. |
