APPARATUS AND METHOD FOR CONTINUOUSLY FORMING AN ELEMENT MADE OF EXPANDED PLASTIC MATERIAL AND CONSTRUCTION ELEMENT

• US 20100159199A1
• Filed: 06/25/2008
• Published: 06/24/2010
• Est. Priority Date: 06/26/2007
• Status: Active Grant

• Current Assignee: Gilanberry Trading, Ltd.
• Original Assignee: Gilanberry Trading, Ltd.
• Inventors: Cretti, Piero
• Granted Patent: US 8,936,453 B2
• Time in Patent Office: Days
• US Class Current: 428/141
• CPC Class Codes: B29C 44/206 Using expandable particles or beads as starting material
• CPC Class Codes: B29C 44/304 Adjusting the belt or roller pressure
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]

Abstract

An apparatus (1) for continuously forming a continuous element (2) made of expanded plastic material comprises: a loading section (8) of a loose mass of granules made of expandable plastic material; a sintering section (16) of the continuous element (2) made of expanded plastic material extending downstream of the loading section (8); a stabilizing section (17) of the continuous element (2) made of expanded plastic material extending downstream of the sintering section (16); a forming runnel (18) extending along the sintering (16) and stabilizing (17) sections and defined between a pair of lateral walls (19, 20) and a pair of gas permeable conveyor belts (21, 22), respectively lower and upper, supported by respective supporting tracks (23, 24). According to the invention, at least one of the supporting tracks (23, 24) of the gas permeable conveyor belts (21, 22) comprises at least one portion extending in the sintering section (16) and angularly tiltable with respect to a transversal centerline plane (π) of the forming tunnel (18) for varying the height of the tunnel (18) in a longitudinal direction. In this way, it is advantageously possible to adjust in an optimal manner both the expansion degree of the granules and their mutual welding to provide a compact structure having the desired homogeneous density and the desired homogeneous and low coefficient of heat conductivity.

Claims

1. An apparatus for continuously forming a continuous element made of expanded plastic material comprising:

a) a loading section of a loose mass of granules made of expandable plastic material;

b) a sintering section of said continuous element made of expanded plastic material, extending downstream of said loading section;

c) a stabilizing section of said continuous element made of expanded plastic material, extending downstream of said sintering section;

d) a forming tunnel extending along said sintering and stabilizing sections and defined between a pair of lateral walls and a pair of gas permeable conveyor belts, respectively lower and upper, said belts being supported by respective lower and upper supporting tracks;

wherein at least one of the supporting tracks of the gas permeable conveyor belts comprises at least one portion extending in the sintering section and angularly tillable with respect to a transversal centerline plane of the forming tunnel for varying the height of the tunnel in the longitudinal direction.

2. The apparatus according to claim 1, wherein said at least one angularly tiltable portion of said at least one supporting track comprises at least one tiltable portion of at least one box-shaped element arranged in the sintering section.

3. The apparatus according to claim 2, wherein said at least one box-shaped element of the sintering section is angularly tiltable and said tiltable portion of said at least one box-shaped element is constituted by a wall of said at least one box-shaped element cooperating with one of said gas permeable conveyor belts.

4. The apparatus according to claim 2, further comprising a delivering element for delivering a hot fluid for expanding the granules made of expandable plastic material arranged at the sintering section.

5. The apparatus according to claim 2, wherein said at least one supporting track comprises at least two structurally independent box-shaped elements arranged in said sintering section and aligned along said forming tunnel, each of said box-shaped elements being angularly tiltable with respect to the transversal centerline plane of said tunnel for varying the height of the tunnel in the longitudinal direction.

6. The apparatus according to claim 2, wherein each of said lower and upper supporting tracks of the gas permeable conveyor belts comprises at least a pair of structurally independent box-shaped elements arranged in the sintering section and aligned along the forming tunnel.

7. The apparatus according to claim 6, wherein at least one of the box-shaped elements of the lower supporting track and at least one of the box-shaped elements of the upper supporting track is angularly tiltable with respect to the transversal centerline plane of the forming tunnel for varying the height of the tunnel in the longitudinal direction.

8. The apparatus according to claim 6, wherein the box-shaped elements of the lower and upper supporting tracks of the gas permeable conveyor belts arranged in the sintering section are symmetrically arranged with respect to the transversal centerline plane of the forming tunnel.

9. The apparatus according to claim 6, wherein the box-shaped elements arranged in the sintering section comprise a sliding block for supporting the gas permeable conveyor belt arranged at least one longitudinal end of said elements.

10. The apparatus according to claim 3, wherein said at least one box-shaped element is angularly tiltable with respect to the transversal centerline plane of the forming tunnel by means of an angular adjusting device cooperating with a longitudinal end of said at least one box-shaped element.

11. The apparatus according to claim 10, wherein said angular adjusting device is provided with a sensor adapted to detect the thrust forces generated in the sintering section upon expansion of the granules made of expandable plastic material and to drive in a vertical direction a displacing device of the longitudinal end of said at least one box-shaped element.

12. The apparatus according to claim 1, wherein at least one of said gas permeable conveyor belts is constituted by a gas permeable flexible element.

13. The apparatus according to claim 12, wherein said gas permeable flexible element has a perforated area comprised between 8% and 20% of its total area.

14. The apparatus according to claim 1, wherein each of the lower and upper supporting tracks of the gas permeable conveyor belts comprises a respective displacing group of the lower conveyor belt and of the upper conveyor belt.

15. The apparatus according to claim 14, wherein said displacing groups of the lower and upper gas permeable conveyor belts are arranged at the sintering section.

16. The apparatus according to claim 1, wherein said displacing groups of the lower and upper gas permeable conveyor belts comprise a supporting and displacing belt substantially of the track type.

81. The apparatus for continuously forming said continuous element according to claim 1, further comprising:

a plant having a section for feeding a loose mass of granules made of expandable plastic material.

82. The apparatus for continuously forming a continuous element made of expanded plastic material according to claim 1, further comprising:

a plant having a feeding section disposed to feed a loose mass of granules made of expandable plastic material, said feeding section being upstream of said forming apparatus; and

a cutting section disposed to cut said continuous element made of expanded plastic material, said cutting section being arranged downstream of said apparatus.

17-64. -64. (canceled)

65. A method for continuously forming a continuous element made of expanded plastic material comprising:

providing a forming tunnel between a pair of lateral walls and a pair of gas permeable conveyor belts, respectively lower and upper, of a forming apparatus;

feeding a loose mass of granules made of expandable plastic material into a loading zone of said apparatus;

forming a continuous element made of expanded plastic material by subjecting said granules to expansion and mutual welding in a sintering zone (36) of said tunnel extending downstream of the loading zone;

stabilizing said continuous element made of expanded plastic material in a stabilizing zone extending downstream of the sintering zone;

wherein said step of forming a continuous element made of expanded plastic material comprises subjecting the mass of granules under forming and mutual welding to a variable pressure along the longitudinal direction of the forming tunnel obtained by varying the height of the tunnel in the longitudinal direction.

66. The method according to claim 65, wherein forming a continuous element made of expanded plastic material comprises subjecting the mass of granules under expansion and mutual welding to a progressively increasing pressure for at least one portion of the sintering zone.

67. The method according to claim 65, wherein forming a continuous element made of expanded plastic material comprises subjecting the mass of granules under expansion and mutual welding to a progressively decreasing pressure for at least one portion of the sintering zone.

68. The method according to claim 67, wherein subjecting the mass of granules under expansion and mutual welding to a progressively decreasing pressure is obtained by progressively increasing the height of the forming tunnel in the longitudinal direction.

69. The method according to claim 65, wherein forming a continuous element made of expanded plastic material comprises:

subjecting the mass of granules under expansion and mutual welding to a progressively decreasing pressure in at least a first portion of the sintering zone, and

subjecting the mass of granules under expansion and mutual welding to a progressively increasing pressure in at least a second portion of the sintering zone.

70. The method according to claim 65, wherein forming a continuous element made of expanded plastic material is carried out so as to obtain a partial penetration of a superficial portion of the continuous element being formed in the sintering zone into a perforated area of at least one of said gas permeable conveyor belts.

71. The method according to claim 70, wherein said at least one gas permeable conveyor belt is constituted by a net made of synthetic material or by a woven fabric.

72. The method according to claim 69, wherein said net made of synthetic material or said woven fabric has a perforated area comprised between 8% and 20% of its total area.

73. The method according to claim 65, wherein said granules are subjected to expansion and mutual welding by delivering a hot expanding fluid into at least one portion of the sintering zone of said tunnel.

74. The method according to claim 65, further comprising moving the continuous element made of expanded plastic material by means of displacing groups arranged at the sintering zone and/or at the stabilizing zone, said displacing groups operating on the lower and upper gas permeable conveyor belts.

75. The method according to claim 74, wherein the displacing groups of the gas permeable conveyor belts arranged in the sintering zone comprise a supporting and displacing belt substantially of the track type.

76. A construction element made of expanded plastic material comprising at least one textured surface, said construction element being obtainable by the steps comprising:

a) subjecting a loose mass of granules made of expandable plastic material to expansion and mutual welding in a sintering zone of a forming tunnel defined between a pair of gas permeable conveyor belts so as to obtain a continuous element made of expanded plastic material; and

b) cutting to size said continuous element;

wherein said at least one textured surface is formed by means of partial penetration of a superficial portion of the continuous element into a perforated area of at least one of said belts.

77. The construction element according to claim 76, wherein said at least one gas permeable conveyor belt is constituted by a net made of synthetic material or by a woven fabric.

78. The construction element according to claim 77, wherein said net made of synthetic material or said woven fabric has a perforated area comprised between 8% and 20% of its total area.

79. The construction element according to claim 76, wherein said at least one textured surface comprises a plurality of microreliefs having a height comprised between 0.5 and 3 mm.

80. The construction element according to claim 79, wherein said microreliefs are uniformly distributed throughout substantially the entire extension of the textured surface of the construction element.