Patent ID: 9724855
Date: 2017-08-08
CPC Classifications: B21B,B21D,B29C,B29D

Claim:
1. A roll forming machine comprising: a pair of processing rolls arranged to face each other, the pair of processing rolls each including cutting parts formed on an outer circumferential portion such that the cutting parts mesh with each other to machine a sheet inserted between the processing rolls; and interference preventing mechanism including a pair of dummy rotating bodies arranged on rotary shafts of the pair of processing rolls, each dummy rotating body including dummy cutting parts the number of which is equal to the number of the cutting parts of each processing roll, wherein, in response to rotational phase deviation between the processing rolls, the interference preventing mechanism is configured to prevent interference between the cutting parts of the processing rolls based on rotational phase deviation that simultaneously occurs between the dummy rotating bodies, wherein the interference preventing mechanism is configured to set a first clearance between the dummy cutting parts of the dummy rotating bodies to be smaller than a second clearance between the cutting parts of the processing rolls, and in response to the rotational phase deviation, the interference preventing mechanism is configured to cause interference to occur between the dummy cutting parts of the dummy rotating bodies.