Patent Number: 6,293,175

Title: Web cut-off device

Abstract: A web cut-off device including a frame defining a piston chamber, a pistonmovable in the piston chamber, a cutter blade attached to the piston suchthat upon movement of the piston in a first direction, the cutter blade isadapted to engage and cut a web, at least one pressure chamber and lowerconnecting ducts for connecting the pressure chamber(s) to a lower part ofthe piston chamber. The ducts opening directly into opposed side wallsdefining the piston chamber such that the piston operates as a valvebetween the piston chamber and the pressure chamber(s). The device alsoincludes at least one return pressure duct in communication with an upperpart of the piston chamber such that upon introduction of pressure intothe return pressure duct(s), the piston is moved in a second directionopposite to the first direction, and at least one bottom duct incommunication with a bottom of the piston chamber such that by introducingpressure into the bottom of the piston chamber via the bottom duct(s),movement of the piston in the first direction is initiated and byevacuating pressure from the bottom of the piston chamber via the bottomduct(s), the piston is maintained stationary in the piston chamber. Amethod for cutting a web using the device is also disclosed.

Inventors: Enwald; Petri (Tuusula, FI), Mannio; Aaron (Jarvenpaa, FI), Ruha; Pekka (Helsinki, FI), Vesterinen; Kalevi (Vantaa, FI)


International Classification:

Expiration Date: 09/25/2013