Abstract: A hole cutter/punch arrangement that can be changed over quickly to a different hole cutter or punch or slitter, or can instead be converted to a sealer in manufacture of items from plastic film. A reciprocating drive such as an air cylinder is coupled to a transverse mount or holder, of a T-shaped profile and the punches and sealers each have a mounting shoe with a transverse T-profile channel to slide onto the mount where a detent holds the shoe releasably in place. A triple-tree arrangement of a center drive post and left and right guide posts connects to the transverse holder.

Abstract: A hole cutter/punch arrangement that can be changed over quickly to a different hole cutter or punch or slitter, or can instead be converted to a sealer in manufacture of items from plastic film. A reciprocating drive such as an air cylinder is coupled to a transverse mount or holder, of a T-shaped profile and the punches and sealers each have a mounting shoe with a transverse T-profile channel to slide onto the mount where a detent holds the shoe releasably in place. A triple-tree arrangement of a center drive post and left and right guide posts connects to the transverse holder.

Abstract: A bow spreader bar provides lateral stress on a web of plastic film as it travels past. An elongated arcuate bow member is supported on a rotatable support bar that can be rotated by a first actuator to adjust pitch angle of the bow member relative to the plane of the film. A second actuator mounted on a midportion of the rotatable bar has a rod connected to a center part of the arcuate member and adjusts the amount of bow or arc of the arcuate member. A remote control arrangement has a receiver coupled to the first and second actuators and a remote transmitter permitting an operator to control the pitch angle and amount of bow from a location remote from the film processing equipment.

Abstract: Gusset boards of a blown film extrusion apparatus have nose portions that can be positioned in the path of a tube of blown film traveling between the nose portions where the nose portions engage with opposite sides of the tube of blown film and form gussets in the tube of blown film. The nose portions of the gusset boards can also reduce their width dimensions which enables the nose portions to be moved away from the path of blown film traveling between the gusset boards when gussets formed in the opposite sides of the tube of blown film are not needed.

Abstract: A safety cover is provided for a cutter head or punch head of the type used in making holes and slits in plastic film, so that the punch head may be transported, stored, installed or removed without exposing the sharp cutting blades to an operator's hands. The safety cover may be of a box-like construction with a generally keyhole-shaped opening formed on its upper wall. The keyhole opening has a wider portion open to the distal or machine side, a narrow slot portion, and a round portion that accommodates the round punch blade of the punch head.

Abstract: A safety cover is provided for a cutter head or punch head of the type used in making holes and slits in plastic film, so that the punch head may be transported, stored, installed or removed without exposing the sharp cutting blades to an operator's hands. The safety cover may be of a box-like construction with a generally keyhole-shaped opening formed on its upper wall. The keyhole opening has a wider portion open to the distal or machine side, a narrow slot portion, and a round portion that accommodates the round punch blade of the punch head.

Abstract: An idler roll employed in a blown film extrusion line is non turning and a plurality of wear strips are removably attached to the idler roll at circumferentially spaced positions around the idler roll. The wear strips engage blown film passing over the idler roll. The wear strips have reduced coefficients of friction than that of the idler roll, have high wear resistances and the blown film passing over the wear strips cleans and polishes the surface area of the wear strips the film moves across, substantially making the wear strips and the non turning idler roll maintenance free compared with idler rollers with bearings.

Abstract: A gusset board has a retractable nose section that travels along a proximal-distal track and can extend to the tip of the gusset board for production of gusseted film, and can retract below the level of interfering structure and moved away from the extrusion bubble for the production on non-gusseted film. Retraction and extension of the nose portion and rocking of the gusset board can be carried out remotely.

Abstract: A clamping arrangement is provided for a slitter and/or hole punch for a plastic film processing machine. The punch can be unitarily formed on a base member, and mounted on a block that is affixed to the end of an actuator rod. A double-acting pneumatic cylinder actuator serves as the reciprocating mechanism for the punch. A hold-down clamping mechanism includes an apertured clamping plate and frame that surrounds the punch and is spring-driven using a compression spring mounted over the shaft or rod of the actuator. The compression spring compresses on the upstroke, and assists the cylinder on the downstroke.

Abstract: An external stabilizer or guide cage for plastic film extrusion has an upper frame comprised of a ring and structure for rotatably supporting the ring. A lower frame is suspended from the ring of the upper frame, and is positioned such that the lower frame surrounds the extruded tube. The lower frame can employ one or several banks of guide arms that keep the tube aligned axially as the tube is drawn upwards. The arms on the lower frame define an iris aperture, or a stack of iris apertures. The arms include channels for coolant flow. Heat transfers from the film to the guide arm. The upper frame includes a drive for rotating the ring and the lower frame of the guide cage over a predetermined arc, e.g., 60 degrees, to compensate for gauge variations in the film.

Abstract: An external stabilizer or guide cage for plastic film extrusion has an upper frame comprised of a ring and structure for rotatably supporting the ring. A lower frame is suspended from the ring of the upper frame, and is positioned such that the lower frame surrounds the extruded tube. The lower frame can employ one or several banks of guide arms that keep the tube aligned axially as the tube is drawn upwards. The arms on the lower frame define an iris aperture, or a stack of iris apertures. The arms include channels for coolant flow. Heat transfers from the film to the guide arm. The upper frame includes a drive for rotating the ring and the lower frame of the guide cage over a predetermined arc, e.g., 60 degrees, to compensate for gauge variations in the film.

Abstract: A multiple variable punch assembly is configurable for punching holes and slits in a plastic film material. The assembly has frame is positioned below the plane of film with one or more transverse carriages positioned to slide on the sides of the frame. Each of the carriages has side plate members, and upper and lower rails extending across the frame in the transverse direction. The upper rail is positioned above the plane of the film and the lower rail is positioned directly below the upper rail and below the film web plane. The positions of the carriages can be adjusted along the frame in the machine direction. The punch head assemblies are adjustably mounted the carriages, with an upper plate fitted onto the upper carriage rail and a lower backing plate situated beneath it on the lower carriage rail. An alignment pin can be inserted into aligned holes for positioning the upper plate and the lower backing plate.

Abstract: A clamping arrangement is provided for a slitter and/or hole punch for a plastic film processing machine. The punch can be unitarily formed on a base member, and mounted on a block that is affixed to the end of an actuator rod. A double-acting pneumatic cylinder actuator serves as the reciprocating mechanism for the punch. A hold-down clamping mechanism includes an apertured clamping plate and frame that surrounds the punch and is spring-driven using a compression spring mounted over the shaft or rod of the actuator. The compression spring compresses on the upstroke, and assists the cylinder on the downstroke.

Abstract: An external stabilizer employed in a plastic film blowing apparatus stacks of swing arm members that create an iris aperture for the extruded film bubble. A tubular die, fed with a supply of molten thermoplastic polymer, extrudes a tube of the molten polymer and injects air into the extruded tube to inflate the tube into a bubble. The wall of the tube expands into a film of a desired thickness; and the tube is drawn vertically upward and collapsed and flattened. The external stabilizer has a frame surrounding the extruded tube above the die. A plurality of swing arms arranged on said frame define the iris aperture. Each of the swing arms is an elongated extrusion of a light-weight material having one end mounted pivotally on the frame and a free end. The swing arm has a mushroom-shaped profile that is rounded on a side that faces the extruded tube. Wear resistant material is disposed on the front surface.

Abstract: A slitter-and-hole-punch and quick change adapter combination fits a bag machine or the like for punching holes and slits in a web of film material. A hole punch and a slitter blade are unitarily formed on a base member. Left and right resilient arms extend from distal to proximal, and have free ends that project proximally of the base member. The quick adapter can be an extruded block with a T-channel formed on a lower side with a passage or gap to accommodate the hole punch and the slitter blade. The T-channel has inwardly directed flanges that create side recesses to accommodate the resilient arms of the slitter-and-hole-punch. The side recesses have cooperating hollows to receive detents of the associated resilient arm. The slitter-and-hole-punch can be slid in and out of the T-slot, and when slid in, the detents on the resilient arms keep it in position. The slitter-and-hole-punch can be changed out in a few seconds by hand. The slitter-and-hole-punch units can be color coded, e.g., for gap size.

Abstract: A bow spreader bar employed in a plastic film processing arrangement incorporates an extruded member and a low-friction plastic wear cover. The bow spreader bar is positioned in advance of the film take-up roll and presses into the film web to eliminate folds, wrinkles, or creases. The extrusion can be of aluminum or another light-weight material having a T-shaped profile that is rounded on a side that faces the film so that the extrusion has an arcuate front surface. The associated wear cover is made of a wear resistant plastic material and is disposed on the arcuate surface of said extrusion. Preferably, the extrusion is formed with one or more tubular portions and can be fitted for fluid cooling. The arcuate surface of the extrusion can be provided with a low-friction surface treatment.

Abstract: An external stabilizer employed in a plastic film blowing apparatus incorporates one or more extruded members that carry a low-friction plastic wear cover. A tubular die, fed with a supply of molten thermoplastic polymer, extrudes a tube of the molten polymer and injects air into said extruded tube to inflate the tube into a bubble. The wall of the tube expands into a film of a desired thickness; and the tube is drawn vertically upward and collapsed and flattened. The external stabilizer is positioned on a frame surrounding the extruded tube above the die to keep the tube aligned on a predetermined path as the tube is drawn upwards. The stabilizer includes at least one extrusion of a light-weight material having a profile that is rounded on a side that faces the extruded tube so that said extrusion has a rounded front surface. The associated wear cover is made of a wear resistant plastic material and is disposed on said rounded front surface of said extrusion.

Abstract: A collapsing board employed in the manufacture of polyethylene film is formed as an extruded aluminum member with a back plate that fastens onto the collapsing frame and an arcuate front face that urges the moving polyethylene extrusion to a collapsed condition. A low friction material is applied onto the arcuate front face. In one preferred embodiment, the low-friction material is in the form of an extruded plastic replaceable wear cover. In another embodiment, a ceramic coating is deposited onto the arcuate front face of the metal extrusion. The plastic wear cover can have a co-extruded two-layer front web, with a lubricant filled front layer and a backing layer of a distinct color that is revealed when the front layer becomes worn from use.