Anchor sheet

Abstract

An improved anchor sheet is described. The anchor sheet can be injection molded from polypropylene and can have a thickness of between 0.031 inches and 0.75. Such an anchor sheet can be molded with hooks and can have an attached resilient layer. Stems integral with the anchor sheet are used to form the hooks, and may be 1 mm high and 0.55 mm in diameter. The density of stems may be approximately 230 per square inch, or approximately 128,000 stems on a plate. An anchor sheet made in this way makes an excellent field of hooks when installed onto a supporting surface such as a floor. This field of hooks can take an overlying decorative covering such as pieces of loop backed carpet. When a resilient layer is attached, for example by ultrasonic welding, to the underside of the anchor sheet, between the anchor sheet and the floor, the anchor sheet can have the right degree of “give”, so that a user can experience some cushioning effect from the resilient layer below the anchor sheet, but with some level of rigidity so that the load of walking is transmitted across a larger surface and does not “dig” into the resilient layer.

1 . An anchor sheet for underlying a floor covering, the sheet comprising: 
 (a) a plastic sheet having a thickness of between 1/16 inches and ¼ inches and having a flexural modulus (ASTM D790) of between 700 and 3600 MPa; and    (b) a resilient layer secured to a first side of the plastic sheet and having a compression force deflection (ASTM D3574-C) that is within about 30 percent of the compression force deflection of a low density polyethylene layer ⅜ inches thick and a density of 30 kg/m 3 .    
   
   
       2 . The anchor sheet of  claim 1  wherein in the plastic sheet is an injection-molded thermoplastic.  
   
   
       3 . The anchor sheet of  claim 1  wherein the plastic is polyethylene.  
   
   
       4 . The anchor sheet of  claim 1 , wherein the plastic sheet has a thickness of between about ⅛ inches.  
   
   
       5 . The anchor sheet of  claim 1 , wherein a second side of the plastic sheet is covered by hooks integrally molded therewith.  
   
   
       6 . The anchor sheet of  claim 6 , wherein the hooks having a density between 160 hooks per square inch to 1200 hooks per square inch, or approximately 230 hooks per square inch, or approximately 330 hooks per square inch.  
   
   
       7 . The anchor sheet of  claim 1 , wherein the resilient layer comprises, or consists essentially of, polyethylene.  
   
   
       8 . The anchor sheet of  claim 1 , wherein the plastic sheet has a flexural modulus of between 1200 and 2600 MPa, or a flexural modulus of between 1300 and 2500 MPa, or a flexural modulus of between 1400 and 2400 MPa, or a flexural modulus of between 1500 and 2300 MPa, or a flexural modulus of between 1600 and 2200 MPa, or a flexural modulus of between 1700 and 2100 MPa, or a flexural modulus of between 1800 and 2000 MPa.  
   
   
       9 . The anchor sheet of  claim 1 , wherein the anchor sheet is a square and having an outer planar dimension in the range of between approximately 12 inches by 12 inches and approximately 36 inches by 36 inches.  
   
   
       10 . The anchor sheet of  claim 9 , wherein the anchor sheet is approximately 24 inches by 24 inches.  
   
   
       11 . An anchor sheet comprising: 
 a sheet with a first and second surface;    the sheet being made of a polypropylene;    hooks projecting from said first surface; and    a resilient layer made of low density polyethylene attached to the second surface;    wherein the sheet has a thickness between 0.062 inches and 0.50 inches.    
   
   
       12 . The anchor sheet of  claim 11 , wherein the sheet has a thickness of approximately 0.125 inches.  
   
   
       13 . The anchor sheet of  claim 12 , wherein the sheet is injection molded.  
   
   
       14 . The anchor sheet of  claim 3 , wherein the anchor sheet is a square in the range of approximately 12 inch by 12 inch to approximately 36 inch by 36 inch.  
   
   
       15 . The anchor sheet of  claim 14 , wherein the anchor sheet is approximately 24 inch by 24 inch.  
   
   
       16 . The anchor sheet of  claim 13 , wherein the first surface bears a field of hooks, the hooks having a density between 160 hooks per square inch to 1200 hooks per square inch.  
   
   
       17 . An anchor sheet shaped to have a substantially flat square lower layer part having an underside covered in a resilient layer and a substantially flat square upper layer part of the same size as the lower layer part having an upper side substantially covered in hooks in which the upper layer part is offset from the lower layer part an equal amount along two adjacent edges to expose two adjacent portions of the lower layer part and in which countersunk holes are formed through the anchor sheet centred on the corners formed by the lower layer part wherein, the sheet has a total thickness between 0.020 inches and 0.75 inches in its thickest part.  
   
   
       18 . The anchor sheet of  claim 17 , wherein the sheet has a thickness between 0.062 and 0.75 inches in its thickest part.  
   
   
       19 . The anchor sheet of  claim 18 , wherein the sheet has a thickness of approximately 0.125 inches at its thickest.  
   
   
       20 . The anchor sheet of  claim 19 , wherein the sheet is injection moulded.  
   
   
       21 . An anchor sheet for use in a subfloor for detachable attachment to a decorative covering, the anchor sheet comprising: 
 an upper surface having a means for detachable attachment to the decorative covering;    a lower surface opposite the upper surface, the lower surface being covered with a resilient layer;    a recess of a first shape reducing the thickness of the anchor sheet in a first area; and    a complete cut through the anchor sheet of a smaller second area within the first area of a second shape;    wherein the sheet has a thickness between 0.020 inches and 0.75 inches.    
   
   
       22 . The anchor sheet of  claim 21 , wherein the sheet has a thickness between 0.062 and 0.75 inches in its thickest part.  
   
   
       23 . The anchor sheet of  claim 22 , wherein the sheet has a thickness of approximately 0.125 inches at its thickest.  
   
   
       24 . The anchor sheet of  claim 21 , wherein the sheet is injection molded.  
   
   
       25 . An anchor sheet comprising: 
 a sheet with a first surface and a second surface;    the sheet being made of one of a polypropylene and a polyethylene, and    a resilient layer attached to the second surface;    wherein the first surface bears a field of hooks, the hooks having a density between 160 hooks per square inch to 1200 hooks per square inch.    
   
   
       26 . The anchor sheet of  claim 25 , wherein the field of hooks has a density of approximately 330 hooks per square inch.  
   
   
       27 . The anchor sheet of  claim 25 , wherein the anchor sheet is a square in the range of approximately 12 inch by 12 inch to approximately 36 inch by 36 inch.  
   
   
       28 . The anchor sheet of  claim 27 , wherein the resilient layer has a thickness between ¼ of an inch and ⅜ of an inch.  
   
   
       29 . The anchor sheet of  claim 28 , wherein the sheet has a thickness between 0.020 inches and 0.75 inches.  
   
   
       30 . The anchor sheet of  claim 29 , wherein the sheet has a thickness between 0.062 inches and 0.75 inches.  
   
   
       31 . The anchor sheet of  claim 30  wherein the sheet is 0.125 inches thick.  
   
   
       32 . An anchor sheet for use in a subfloor for detachable attachment to a decorative covering, the anchor sheet comprising: 
 an upper surface having a means for detachable attachment to the decorative covering;    a lower surface opposite the upper surface, the lower surface being attached to a resilient layer;    one of an overlay and an underlay area located adjacent an edge of the anchor sheet, wherein the anchor sheet has a reduced thickness in the area, and the area is configured to overlap with the other of an overlay and underlay area of a complementary anchor sheet; and    wherein the anchor sheet has a maximum thickness of between 0.020 inches and 0.75 inches.    
   
   
       33 . An anchor sheet for use in a subfloor for detachable attachment to a decorative covering, the anchor sheet comprising: 
 an upper surface having a means for detachable attachment to the decorative covering;    a lower surface opposite the upper surface, the lower-surface being attached to a resilient layer; and    one of a male and female feature defined in the anchor sheet and located adjacent an edge of the anchor sheet, the feature being configured to interlock with the other of male and female feature of a complementary anchor sheet.    
   
   
       34 . The anchor sheet of  claim 33 , wherein the feature is keystone-shaped.  
   
   
       35 . The anchor sheet of  claim 33 , wherein the feature is jigsaw puzzle piece-shaped.  
   
   
       36 . An anchor sheet comprising: 
 a first layer of a polypropylene sheet of between 0.062 inches and 0.50 inches; and    a second layer of polyethylene foam of a density of at least 20 kg/m 3  and of thickness of between ¼ inches and ⅜ inches.    
   
   
       37 . The anchor sheet of  claim 36  in which the anchor sheet provides for countersunk areas at least along one edge.