Flat sheet injection head for roller-head installations

Claim 2

Roller head apparatus comprising; a calender stand; calender rolls rotatably supported by said stand and defining a nip between the rolls; an extruder barrel; an extruder screw rotatable therein for the extruding of material in a plastic state from said barrel; an elongate injection head for said barrel aligned with said nip, said injection head defining an elongate flat sheet extruder nozzle for said extruding of material and comprising two elongate parts generally disposed on opposite elongate sides of said elongate flat sheet extruder nozzle; rigid means mounted on said calender stand and extending along said Elongate injection head; means supporting a first of said elongate parts of said injection head mounted stationary on said rigid means, the other of said elongate parts of the injection head being mounted on said barrel and being movable therewith toward and away from said calender stand and rolls; and pressure means mounted on said rigid means for acting between the same and said movable elongate part of the injection head for releasably pressing this part toward said stationary elongate part, in portions of said parts including at least a central portion thereof, to counteract distortion of said movable elongate part in the use of the apparatus.

Claim 3

Calender apparatus, comprising; a calender stand; calender rolls rotatably supported by the stand and defining a nip between the rolls; an extruder barrel; an extruder screw rotatable therein for extruding material in a plastic state from the barrel; a flat sheet extruder head defining an extruder aperture elongate transversely of said barrel, the head being disposed in use for extruding material in a plastic state from the barrel through the elongate aperture into the nip between the calender rolls, the extruder head comprising first and second, similarly elongate parts generally disposed on mutually opposite, elongate sides of said aperture; rigid stationary means mounted on said stand, extending along said elongate extruder head, and rigidly stationarily supporting the first elongate part of said extruder head, the second elongate part of said extruder head being mounted on said barrel and being mounted for movement therewith toward and away from said rigid stationary means; and pressure means mounted on said rigid means and actuatable between said rigid means and said second elongate movable elongate part for releasably pressing at least a central portion of said second elongate movable part toward said first elongate part to counteract distortion of the second elongate movable part in the use of the extruder.

Claim 4

Calender apparatus, comprising; a calender stand; calender rolls rotatably supported by the stand and defining a nip between the rolls; an extruder barrel; an extruder screw rotatable therein for extruding material in a plastic state from the barrel; a flat sheet extruder head defining an extruder aperture elongate transversely of said barrel, the head being disposed in use for extruding material in a plastic state from the barrel through the elongate aperture into the nip between the calender rolls, the extruder head comprising first and second, similarly elongate parts generally disposed on mutually opposite, elongate sides of said aperture; rigid stationary means mounted on said stand, extending along said elongate extruder head, and rigidly stationarily supporting the first elongate part of said extruder head, the second elongate part of said extruder head being mounted on said barrel and being mounted for movement therewith toward and away from said rigid stationary means; and pressure means mounted on said rigid means and actuatable between said rigid means and said second elongate movable elongate part for releasably pressing at least a central portion of said second elongate movable part toward said first elongate part to counteract distortion of the second elongate movable part in the use of the extruder.

Claim 5

Apparatus according to claim 2 wherein said rigid means mounted on said stand comprises first and second parallel beams spaced apart across said extruder head and each extending along said extruder head, the first beam supporting said first elongate part and the second beam supporting said pressure means.

Claim 6

Apparatus according to claim 3 in which the barrel and the second elongate movable part of the extruder head mounted thereon are disposed for movement to and away from said second beam and pressure means, the latter means being actuatable by the movement of said second elongate movable part to said rigid stationary means.

Claim 7

Apparatus according to claim 4 in which the pressure means comprises a plurality of wedge means distributed along said extruder head and actuatable to act between said rigid means and said elongate movable part of the extruder head, and means for actuating the wedge means.

Claim 8

Apparatus according to claim 5 in which the means for actuating the wedge means comprises fluid pressure actuatable piston means mounted on said rigid means.

Claim 9

Apparatus according to claim 2 in which the pressure means comprises a plurality of fluid pressure actuatable piston means mounted on said rigid means and actuatable to act between said rigid means and said elongate movable part of the extruder head.

Claim 10

Apparatus according to claim 2 in which the pressure means comprises a fluid pressure cushion for acting between said rigid means and said elongate movable part of the extruder head.

Claim 11

Apparatus according to claim 2 in which the pressure means comprises a plurality of pressure elements disposed at selected points along the elongate movable part of the extruder head for applying locally different pressures to said part.