Apparatus for trimming opening rims of synthetic-resin containers

Claim 1

Apparatus for automatically trimming opening rim parts of synthetic-resin container structures comprising, in combination: a revolving support structure (15) driven by motive power means; a plurality of trimming devices mounted on said support structure to undergo orbital revolution thereon, each of said trimming devices comprising a container holding device (3) provided with a rotary member (3) rotatably supported for rotation about its own axis and adapted to hold a container structure (49) inserted thereinto, clamping means rotating with said rotary member and adapted to clamp and firmly hold said container structure near the rim of an opening thereof, and a cutting-tool device actuatable to advance and retract a cutting tool (35) to and away from said rim part; and coordinating means for coordinating the operations of the above named parts thereby to accomplish the operational steps, with respect to each trimming device during one orbital revolution thereof, of A. causing the rotary member to stop its rotation and, in that state, receive a container structure to be trimmed and said clamping means to hold said rim part of said structure, B. causing the rotary member to rotate about its axis and the cutting-tool device to advance to said rim part thereby to trim surplus material thereof. C. braking the rotary member and stopping the same in a specific angular position, and D. causing the clamping means to open and release the container structure thereby to permit the same to be discharged from the apparatus, the foregoing steps A, B, C, and D being repeatedly and continuously carried out with respect to all trimming devices in succession.