Processes and apparatuses for perforating smooth, closed-cell surfaces of open-cell plastic foam sheets
First Claim
1. An apparatus for perforating one or more smooth, closed surfaces of open-cell plastic foam sheets, wherein the apparatus comprises:
- a movable mold block adapted for molding an inner side of the plastic foam sheet, said movable mold block comprises;
needles arranged in a matrix in the movable mold block,one or more needle plates having the needles arranged thereon, such that during a perforation operation needle tips of said needles project from the surface of said movable mold block to such an extent that they pierce a surface skin of the plastic foam sheet,springs within the movable mold block adapted for returning the one or more needle plates after the perforation operation,a cooling plate,a male mold mounted on the cooling plate,a vacuum plate bearing against an underside of the cooling plate,a mounting plate, andone or more diaphragms located between the vacuum plate and the mounting plate, wherein all parts of said movable mold block being held together; and
a further mold block, adapted for molding an outer side of the plastic foam sheet.
2 Assignments
0 Petitions
Accused Products
Abstract
Open-cell plastic foam sheets with smooth, closed surfaces are heated up to a predetermined temperature after extrusion, are thermoformed in a thermoforming unit with the aid of a vacuum on both sides and are thermoset. One of the two closed surface skins of the plastic foam sheet is perforated with the aid of needles 4 arranged movably in a mold block 11. The mold block 11 is a component part of a thermoforming unit 10 and, together with a further mold block 9, forms the mold of this thermoforming unit. The mold block 11 for the inner side 13 of a plastic foam sheet 16 comprises a male mold 1, a cooling plate 2, a vacuum plate 3, the movable needles 4, a needle plate 5, springs 6 for the return of the needle. plate and also diaphragms 7 and a mounting plate 8, which are held together by screws 30.
62 Citations
45 Claims
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1. An apparatus for perforating one or more smooth, closed surfaces of open-cell plastic foam sheets, wherein the apparatus comprises:
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a movable mold block adapted for molding an inner side of the plastic foam sheet, said movable mold block comprises; needles arranged in a matrix in the movable mold block, one or more needle plates having the needles arranged thereon, such that during a perforation operation needle tips of said needles project from the surface of said movable mold block to such an extent that they pierce a surface skin of the plastic foam sheet, springs within the movable mold block adapted for returning the one or more needle plates after the perforation operation, a cooling plate, a male mold mounted on the cooling plate, a vacuum plate bearing against an underside of the cooling plate, a mounting plate, and one or more diaphragms located between the vacuum plate and the mounting plate, wherein all parts of said movable mold block being held together; and a further mold block, adapted for molding an outer side of the plastic foam sheet. - View Dependent Claims (5, 9, 10, 11, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31)
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2. An apparatus for perforating one or more smooth, closed surfaces of open-cell plastic foam sheet comprising:
a fixed mold block adapted for molding the side walls and the bottom of a tray or a container from a plastic foam sheet, wherein the fixed mold block comprises a fixed base plate with mutually parallel channels disposed in the base plate and lying one above the other and adapted for transporting a cooling medium, vacuum and pressure medium, and a male mold having needle pistons, and needles having needle tips arranged on the needle pistons, wherein during a perforation operation the needles with needle tips extend perpendicularly from their positions within the male mold onto the side walls and the bottom lying opposite the surface of the male mold. - View Dependent Claims (6, 12, 13, 14, 32, 33, 34, 35, 36, 37)
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3. An apparatus for perforating one or more smooth, closed surfaces of open-cell plastic foam sheet comprising:
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a base frame with vertical guide rods; a pressure plate mounted in a fixed position on the guide rods; a mounting plate displaceably arranged along the guide rods; and a mold block disposed on the mounting plate, wherein said mold block comprises a base plate; and one or more perforating blocks containing movable or fixed needles arranged in a matrix arrangement, wherein the one or more perforating blocks are adapted such that during a perforating operation the needles with needle tips project from the surface of the one or more perforating blocks to such an extent that they pierce a surface skin of the plastic foam sheet. - View Dependent Claims (7, 15, 16, 38, 39, 40, 41, 42, 43, 44)
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4. An apparatus for perforating one or more smooth, closed surfaces of open-cell plastic foam sheets, wherein the apparatus comprises:
a mold block which comprises; a cooling plate; a mounting plate; a male mold having a top wall and sidewalls; and fixed needles anchored in the top wall and sidewalls of the male mold, wherein the tips of the fixed needles project outward from the male mold, wherein the mold block is disposed in a thermoforming unit, and wherein the mold block is adapted such that during a perforation operation the needles with the needle tips project from a surface of the male mold to such an extent that the pierce a surface skin of the plastic foam sheet. - View Dependent Claims (8, 45)
Specification