Method of continuously producing elongated plastic siding panels

Abstract

A method and an apparatus for continuously producing elongated siding panels is disclosed. The apparatus includes a conveyor, a plurality of mold plates, and a die for extruding a sheet of material onto the mold plates. The mold plates are formed of a rigid material and positioned adjacent one another and supported by the conveyor for forming the elongated siding panels. Each of the mold plates has an upper edge portion and a lower edge portion with an intermediate portion therebetween. The intermediate portion has an aesthetic pattern for imparting the pattern to the sheet of material with the adjacent mold plates having different aesthetic patterns. The lower edge portion has a lower leg extending substantially perpendicular from the intermediate portion defining a horizontal plane and a projection portion between the lower edge portion and the intermediate portion extends beyond the horizontal plane for imparting a jagged pattern to the intermediate portion.

1 - 23 . (canceled) 
     
     
         24 . A method of continuously producing elongated siding panels, each panel having an upper edge portion, an intermediate portion having an aesthetic pattern, and a lower edge portion having a lower leg extending substantially perpendicular from the intermediate portion defining a horizontal plane, said method comprising the steps of:
 extruding a sheet of material having a temperature sufficient for vacuum forming the sheet of material;   directing the sheet of material onto a plurality of mold plates carried by a conveyor, each of the mold plates having an upper edge portion, a lower edge portion, and an intermediate portion having an aesthetic pattern disposed therebetween;   progressively applying a vacuum to the mold plates as the mold plates travel along the conveyor;   drawing the sheet of material into the mold plates when the vacuum is applied;   forming the upper edge portion, the intermediate portion, and the lower edge portion while the entire sheet of material has the sufficient temperature for vacuum forming; and   forming a projection portion between the lower edge portion and the intermediate portion simultaneously with the forming of the lower edge portion and the intermediate portion wherein the projection portion extends beyond the horizontal plane to impart a jagged pattern to the intermediate portion.   
     
     
         25 . A method as set forth in  claim 24  further comprising the step of forming the projection portion angled upwardly at an angle of less than ninety degrees from the intermediate portion toward the lower leg. 
     
     
         26 . A method as set forth in  claim 25  wherein the step of forming the projection portion is further defined as varying a depth of the projection portion between adjacent molds for increasing the jaggedness of the panel. 
     
     
         27 . A method as set forth in  claim 25  further comprising the step of forming a locking channel in the lower edge portion while the entire sheet of material has the sufficient temperature for vacuum forming. 
     
     
         28 . A method as set forth in  claim 27  further comprising the step of forming a mounting flange having a locking groove in the upper edge portion simultaneously with the formation of the locking channel. 
     
     
         29 . A method as set forth in  claim 28  wherein the step of forming the mounting flange is further defined as forming an interlock having two corners with one of the corners having a substantially right angle. 
     
     
         30 . A method as set forth in  claim 28  further comprising the step of cooling the entire sheet of material below the temperature sufficient for vacuum forming after the sheet of material has been vacuum-formed. 
     
     
         31 . A method as set forth in  claim 30  further comprising the step of heating a line spaced inward from a terminal edge of the upper edge portion dividing the upper edge portion into a first part spaced inward from the line and a second part spaced outward from the line such that the first part and the second part remain at a temperature below a temperature of the line. 
     
     
         32 . A method as set forth in  claim 31  further comprising the step of bending the second part relative to the first part to define an interlock of said upper edge portion. 
     
     
         33 . A method as set forth in  claim 32  further comprising the step of trimming excess material from the upper and the lower edge portions prior to heating the line. 
     
     
         34 . A method as set forth in  claim 33  further comprising the step of cutting the sheet of material at longitudinally spaced intervals to produce the succession of separate elongated siding panels. 
     
     
         35 . A method as set forth in  claim 34  further comprising the step of detecting a micro-switch cam in one of the upper and lower edge portions and cutting the sheet of material in response to detecting the micro-switch cam. 
     
     
         36 . A method as set forth in  claim 24  further comprising the step of urging the sheet of material into the projection portion with a plug-assist. 
     
     
         37 . A method as set forth in  claim 36  wherein the step of urging the sheet of material is further defined as rotating a plurality of mold inserts into engagement with adjacent mold plates as the conveyor is operated. 
     
     
         38 - 66 . (canceled)