Bladder for slotter head assembly having pneumatically locked slotter blades

A rotatable slotter head, comprising:

• a rotatable body including a pair of opposed, arcuate plates adjacent the periphery of the body cooperatively defining therebetween an elongated, knive-receiving slot adjacent to said periphery, one of said plates presenting a pair of opposed side faces and being mounted for limited travel thereof toward and away from the opposed plate;
• an elongated pneumatic bladder presenting an outer surface and a plate-engaging surface, said bladder carried within a recess of said body, said recess presenting an interior sidewall in registry with said bladder outer surface, said recess located for engagement with the side face of said one plate remote from said opposed plate;
• and
• means for selectively pressurizing said bladder with fluid for movement of said one plate towards said opposed plate in response to radial movement of said plate-engaging surface in order to engage and lock a knife, and for permitting selective depressurization of said bladder for releasing said knife.

A knife assembly, comprising:

• an elongated, axially rotatable shaft;
• an annular head presenting a periphery and a pair of opposed, laterally spaced apart walls extending inwardly from said periphery and cooperatively defining a knife-receiving slot therebetween, a recess associated with said head and adjacent a wall side of one of said walls opposite said slot;
• said head mounted on said shaft for rotation of the head and said slot-defining walls with the shaft at all times;
• an arcuate knife having a length substantially less than the length of said knife-receiving slot and position within the slot;
• means for releasably locking said knife within said slot,
• including at least one elongated bladder having an outer surface and a knife-locking surface presented between opposite bladder ends, said bladder outer surface receivable by and registrable within said recess, said bladder having structure for selective and alternate placement of the bladder in either a pressurized or depressurized condition;
• and
• knife-engaging means operably coupled with said bladder for engaging said knife when said bladder is in one of said conditions for locking the knife in place in a desired position within said slot, and for releasing said knife when said bladder is in the other of said conditions for permitting shifting movement of the knife within and along the length of said slot and relative to both said shaft and both of said slot-defining walls, in order to change the relative position of the knife within said slot without shaft rotation and independently of the rotational position of the shaft.