Abstract:
A rib forming apparatus has an elongated support table, a supply of thermoplastic sheet material over the table, a transporting means having at least two transverse carriages mounted on the table to slide along longitudinal edges thereof, a thermal means mounted on one of the carriages for locally heating the sheet material in preparation of a molding press, and at least one press module mounted on another carriage and having a reciprocating press blade positioned at one flat side of the sheet material and a couple of swiveling press blades positioned at the opposite flat side of the sheet material and movable toward the reciprocating press blade to mold the heated section of the sheet material by closing the above three press blades toward each other, whereby a series of vertical rib folds are formed transversely of the sheet material and advanced by the transport means through the closed press blades.

Description:
This application is a continuation in part of Dworzan U.S. patent application Ser. No. 11/435,834 filed May 16, 2006. 
   CROSS REFERENCE TO RELATED APPLICATIONS 
   Smith U.S. Pat. No. 5,477,639 
   Smith U.S. Pat. No. 5,615,517 
   Dworzan U.S. patent application Ser. No. 11/435,834 

   BACKGROUND OF THE INVENTION 
   A. Field of the Invention 
   The present invention relates to a plastic forming apparatus for making a plastic panel with transverse ribs. More particularly, the present invention relates to a manufacturing apparatus for making a plastic panel with rib folds such as a root barrier panel material used in the landscaping field to control outgrowth of tree roots. 
   B. Description of the Prior Art 
   Folding machines for sheet plastic or sheet metal or the like are plenty. A more advanced type of such an apparatus is disclosed in U.S. Pat. No. 6,939,284 to Trovinger at al. the disclosure of which is incorporated herein by reference. Trovinger teaches a sheet folding apparatus with a rounded fold blade. Trovinger&#39;s patent makes a single center fold of a piece of sheet using a fold roller that runs around a round fold blade and depresses the sheet material between the fold blade. When regularly distanced transverse folds are necessary on a continuous supply of plastic sheet for use in various constructive walls that need ribs, this and other known devices come short in providing an adequate speed and quality of evenly spaced ribbed sheets or plates. 
   An object of the present invention is to provide an automatic rib forming apparatus for thermoplastic sheet plastic that is mechanically simplified and optimized to produce a speedy folding of well-defined ribs from a flat surface. 
   Another object of the present invention is to provide a novel combination of rack-and-pinion gears with four-bar linkage of parallel motion to mold and advance the sheet material to optimize the otherwise complex machine operations. 
   Yet another object of the present invention is to provide a method of forming an elongated panel with transverse ribs with improved efficiency. 
   SUMMARY OF THE INVENTION 
   The rib forming apparatus of the present invention is generally used to manufacture a long plate article that has a plurality of transverse folds formed as integral ribs for various purposes. Examples of such a plate article are general-purpose wall elements with reinforcing ribs or ribs having a special function of self-locking feature such as described in an applicant&#39;s earlier application Ser. No. 11/435,834 titled “Root Barrier”, hereby incorporated by reference. 
   Typically, the barrier product is introduced in landscape linear applications. A cut of such barrier product may be flexed into a circular form and locked onto itself by joining opposite end ribs so that one rib clips the other without requiring separate fasteners. 
   A rib forming apparatus according to the present invention comprises an elongated support table, a supply of thermoplastic sheet material over the table, a transporting means having at least two transverse carriages mounted on the table to slide along longitudinal edges thereof, a thermal means mounted on one of the carriages for locally heating the sheet material in preparation of a molding press, and at least one press module mounted on another carriage and having a reciprocating press blade positioned at one flat side of the sheet material and a couple of swiveling press blades positioned at the opposite flat side of the sheet material and movable toward the reciprocating press blade to mold the heated section of the sheet material by closing the above three press blades toward each other, so that a series of vertical rib folds are formed transversely of the sheet material and advanced by the transport means through the closed press blades. The transport means also includes a hydraulic or air power source flexibly connected to the carriages. 
   The three interconnected carriages straddle across the table and are slidingly mounted on two parallel rods, which extend longitudinally and fixedly mounted on the table. The first longest carriage at the entry may be made of a hollow structure of steel, aluminum or any other material with a good mechanical strength to carry the thermal means comprising two identical electric heaters where the plate material is first introduced. 
   The first carriage shuttles between two sliding positions relative to the plate material by a longitudinal carriage actuator, which is preferably mounted under the table and connected to a hydraulic or electric power source not shown. The heaters on the carriage contain two parallel hot wires distanced correspondingly with the even pitch of the ribs to be molded and are positioned right above the plate material to heat its two transverse sections to prepare the plate for the rib molding. 
   With a short distance to the first carriage a second carriage is resiliently connected through a couple of spring-biased expansive fasteners at either end thereof and carries a second press, which is operated by its designated vertical actuator. The carriage and press actuators of the present invention may be commonly connected to a single hydraulic or electric power source through an appropriate pipage along the sides of the support table. An end carriage is similarly connected to the second carriage through a couple of spring-biased expansive fasteners. Therefore, the three carriages permit the thermal station and molding station to shuttle together in a loose unity along the rods due to the single carriage actuator. 
   The advancement of the plate material may be effected by the crimping grip of the presses combined with the telescoping operation of the carriage actuator. The press grabs the material and pulls it to advance new and unformed material. 
   The molding press comprises two opposite base plates attached to a common carriage facing each other and two back-to-back rack-and-pinion gear set on each of the base plates for forming two parallelogram linkages actuated by an actuator with reciprocating rods, which are attached to the distal ends of the two rack gears so that the rack gears reciprocate at the same time. The movements of each rack gear rotate two pinion gears that are meshed therewith. Arms rotationally fixed to the respective pinion gears and cross-links pivotally connecting two adjacent arms form a pair of parallelogram linkages, which are then synchronized by transverse shafts with the counterparts on the opposite parallelogram linkages formed in mirror image on the opposing base plate. 
   But two rack gears on one of the two base plates have free ends with no actuator directly connected thereto. Instead, the rack gears are driven by an upright molding blade acting as a central mold of a triple mold system of the present invention. 
   The central blade is shaped like an inverted T made of metal or a comparatively strong composite material and has a corner chamfered at an end and a similar corner at the opposite end. The attachments between the rack gears and molding blade may be done through welding or using mechanical fasters, which need boring through the adjacent walls. 
   Extending along the sides of the central blade are a pair of side molding blades that are affixed to the cross-links of the opposing base plates respectively at their ends close to the table so that upon swivel movements of the cross-links the side blades exert a crimping force laterally as well as vertically against the plate material over the central blade as it moves vertically toward the closing side blades resulting in a crimp molding of the ribs of the plate material from three sides. The ribs will be formed at an even interval along the length of the flat material. 
   In the preferred embodiment where two press modules are installed side by side, upon retraction of the carriage actuator with simultaneous extensions of the press actuators, the whole rib forming apparatus slides over the plate material two pitches corresponding to two ribs and their adjacent plate sections back toward its fresh blank section to mold another two ribs at the same time. 
   As soon as the plate material receives new rib crimping at the molding phase, the subsequent extension of the carriage actuator automatically advances the processed plate section one pitch followed by another retraction of the same actuator for the next rib molding. Meanwhile, the plate material is held from moving backward with the assist of a simple angled stick fixed to an output area of the table for catching the ribs one way. 
   The present invention also provides the method of making integral ribs on a thermoplastic sheet material. Unreeled sheet from a roll run through two heaters with suspended heat cores under which upward bends of the sheet are initiated during a thermal deformation that also softens the sheet in preparation for the subsequent hot clamp-molding step. For a set pitch of the ribs, the distance of the heaters from each other and the adjacent press is firmly determined considering the shrinking length of the plate by the right-angled sidewalls and the connecting bends which amount to two adjacent ribs. The pitch may be modified by adding distance between the presses with the use of a spacer affixed to one of the base plates at its abutting side and correspondingly increasing the distance between the heaters. 
   By closing the central blade and side blades the upright ribs are molded across the width of the sheet. 
   As rack gears switch from their extended position to retracted position along with the central blade swinging the side blades apart, they are transported back to the molding position from where they had released the last rib. With the ribs closed in the presses they will advance all together to output the finished plate section pulling the next hot areas of the plate toward the molding positions. 
   According to a third embodiment of a rib forming apparatus of the present invention orientation of the apparatus may be vertical instead of horizontal. By having the entire apparatus turned with appropriate frame modification, it requires less floor space. Changing the direction of advancement of the plate material brings the advantage of gravity effect of naturally straightening the finished plate. In this orientation, the rib forming apparatus may be installed as a vertical end unit to a bigger plastic processing plant. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a rib forming apparatus according to the present invention. 
       FIG. 2  is an enlarged perspective view of a press station of the rib forming apparatus of  FIG. 1 . 
       FIG. 3  is an exploded perspective view showing a molding blade assembly of the press station of the rib forming apparatus. 
       FIG. 4A  is a perspective view of a first upper stroke of a molding cycle of the press station showing a double molding press in its open position ready for an introduction of an elongated web material to shape. 
       FIG. 4B  is a perspective view of a second lower stroke of a molding cycle of the press station showing the double molding press in its closed position to effect the molding of series of transverse ribs on the web material, which is omitted for clarity. 
       FIG. 5  is a schematic side view of the rib forming apparatus. 
       FIG. 6A  is a side view of the press station of the rib forming apparatus showing the double mold positioned surrounding the heat-treated web from a previous stage before it is shaped. 
       FIG. 6B  is a side view of the press station of the rib forming apparatus with the double mold actuated to make two rib folds of the web in the same pitch as leading rib folds formed earlier. 
       FIGS. 7A and 7B  are side views of a press station according to a second embodiment of a rib forming apparatus of the present invention with vertical orientation. 
       FIG. 8  is a side view of a rib forming apparatus according to a third embodiment of the present invention having an extended bed area to flatten the unreeled web material before processing. 
       FIG. 9  is a front view of the rib forming apparatus of the present invention. 
       FIG. 10  is a perspective view of a root barrier made by the rib forming apparatus of the present invention. 
       FIG. 11  is an enlarged view of the root barrier of  FIG. 10  in circle at an interlocking engagement between the opposite end ribs. 
   

   Similar reference numbers denote corresponding features throughout the attached drawings. 
   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1  generally depicts a rib forming apparatus  10  according to a first embodiment of the present invention. The apparatus  10  has a support table  11  of steel framework, on which a roll  12  of a thermoplastic web material is held at a starting end to release a continuous supply of an elongated plate  13  to mold with ribs integrally formed to it. 
   The rib forming apparatus  10  of the present invention is generally used to manufacture a long plate article that has a plurality of transverse folds formed as integral ribs for various purposes. Examples of such plate article are general-purpose wall elements with reinforcing ribs or ribs having a special function of self-locking feature such as described in an applicant&#39;s earlier application Ser. No. 11/435,834 titled “Root Barrier”, hereby incorporated by reference. 
   A cut of such barrier product may be flexed into a circular form and locked onto itself by joining opposite end ribs so that one rib clips the other without requiring separate fasteners. More detail of the root barrier will be discussed hereinafter. 
   The rib forming apparatus  10  has three interconnected carriages  14  to  16  that straddle across the table  11  and are slidingly mounted on two parallel rods  17 , which extend longitudinally and fixedly mounted on the table  11 . 
   The first longest carriage  14  at the entry may be made of a hollow structure of steel, aluminum or any other material with a good mechanical strength to carry a thermal station comprising two identical electric heaters  20  where the plate material  13  is first introduced. 
   The first carriage  14  shuttles between two sliding positions relative to the plate material  13  by a longitudinal carriage actuator, which is under the table  11  and is connected to a hydraulic or electric power source not shown. The heaters  20  on the carriage  14  contain two parallel hot wires distanced correspondingly with the even pitch of the ribs to be molded and are positioned right above the plate material  13  to heat its two transverse sections to prepare the plate  13  for the rib molding. 
   Also fixed to the first carriage  14  at its exit side is a first press  21  activated by a vertical actuator  22  and crimps the plate material  13  from its top and bottom sides to mold one of the ribs  23 . 
   With a short distance to the first carriage  14  a second carriage  15  is resiliently connected through a couple of spring-biased expansive fasteners  24  at either end thereof and carries a second press  25 , which is operated by its designated vertical actuator  26 . The carriage and press actuators of the present invention may be commonly connected to a single hydraulic or electric power source through an appropriate pipage along the sides of the support table  11 . In order to follow the sophisticated movements between the components of the rib forming apparatus  10 , it is preferable to use a flexible connector like elastomeric pipes for the hydraulic actuation. A control box  27  may contain power level monitors and an input interface for an operator to control the power supply to the actuators although the rib forming according to the present invention is automatic after an initial setup and requires little to no human intervention. 
   The rib forming apparatus  10  may be easily integrated into an existing thermoplastic molding plant in order to manufacture the ribbed plate as the plastic web is extruded or molded. In this case, the heaters  20  may be omitted because the material is already in a soft state for the immediate molding process of the present invention. 
   An end carriage  16  is similarly connected to the second carriage  15  through a couple of spring-biased expansive fasteners  24 . Therefore, the three carriages  14 - 16  permit the thermal station and molding station shuttle together in a loose unity along the rods  17  due to the single carriage actuator. 
   The number of the rib-forming press is arbitrary as it fits the individual requirements based on the space available, production rate desired or any other factors considered. Because the molding press  25  on the second carriage  15  is modular the number of such presses may be easily changed as necessary with the corresponding change in the number of the heaters  20 . 
   Like this embodiment where presses used are two as well as single or several units, the advancement of the plate material  13  may be effected by the crimping grips of the presses  21 ,  25  combined with the telescoping operation of the carriage actuator. When a higher number of presses are combined, it is practical to have a dedicated transporting means for the processed plate sections instead of shuttling the whole carriage group a longer distance to meet a blank plate material unreeled from the web  12 . In that case, the thermal and molding stations may be made stationary relative to the table  11  and a nib roller device may be installed as is well known in the skill of material handling. 
   Referring to  FIG. 2 , the mechanism of the molding station of the present rib forming apparatus will be described. 
   The press  21  has two rectangular base plates  28 ,  29  with legs  30 ,  31  attached to the opposite ends of the carriage  14  perpendicularly. On each of the base plates  28 ,  29  a pair of rack-and-pinion mechanisms are installed in a symmetrical manner. 
   Two pairs of rack gears  32 ,  33  are positioned longitudinally of and close to each of the base plates  28 ,  29 . The rack gears  32 ,  33  are held back to back across the inner surface of the base plates  28 ,  29  and the actuators  22 ,  26  have reciprocating rods  34 ,  35  attached to the distal ends of the rack gears  32 ,  33  by cross members  38 ,  39  so that the rack gears  32 ,  33  reciprocate at the same time. The actuators  22 ,  26  are connected to a hydraulic power source or air power source, not shown. 
   Meshing with the rack gear  32  two pinion gears  40 ,  41  are fixed to two parallel transverse shafts  42 ,  43  rotationally received in bores  44 ,  45  formed in the opposing base plates  28 ,  29  to cooperatively position the shafts  42 ,  43  in parallel across the carriage  14 . Likewise, another pair of pinion gears  46 ,  47  are in mesh with the rack gear  33  and fixed to two parallel shafts  48 ,  49  rotationally received in bores  44 ′,  45 ′ formed in the opposing base plates  28 ,  29  to cooperatively position the shafts  48 ,  49  in parallel across the carriage  14 . 
   Therefore, two pairs of pinion gears  40 ,  41  and gears  46 ,  47  in the base plate  28  are simultaneously in mesh with the rack gears  32 ,  33  from the opposite sides to provide well balanced transmissions of the linear motion of the rack gear  32  into the rotational displacement of the pinion gears  40 ,  41 ,  46 ,  47 . 
   The opposite base plate  29  has a similar rack-and-pinion gearing fixed to the other ends of the shafts  42 ,  43  and shafts  48 ,  49  without an actuator because the actuator  22  activates both sides of the gear mechanisms in the first modular press  21 . 
   In addition, each of the pinion gears  40 ,  41 ,  46 , and  47  has an assigned arm  50  fixed immovably to the respective pinion shafts. When the rods  34 ,  35  of the actuators  22 ,  26  are in their extended positions the arms  50  are oriented to extend substantially parallel to the rack gears  32 ,  33  on the base plate  28  toward the proximal ends of the gears  32 ,  33 . On the other hand, when the rods  34 ,  35  go to their retracted positions the four arms  50  swing away from the rack gear  32  at the same time wherein the arms  50  of the pinion gears  40 ,  41  are slanted about their respective shafts  42 ,  43  at a common angle such as 80° while the arms  50  of the pinion gears  46 ,  47  are slanted similarly but at a symmetrical posture to the arms  50  at the other side with reference to the center line between the two rack gears  32 ,  33 . 
   Then, the distal ends of the two arms  50  at the side of the rack gear  32  are joined by a cross-link  51  to form a parallelogram linkage whereby the cross-link  51  follows the swinging translations of the pinion gears  40 ,  41  in a parallel posture relative to the gear  32 . The cross-link  51  has a side cut facing the gear set  32 ,  33  to accept rather than colliding with the shaft  43  when the arms  50  and cross-link  51  come into a superimposing relationship with each other. 
   Likewise, the distal ends of the two arms  50  at the side of the rack gear  33  are joined by a cross-link  52  to form another parallelogram linkage whereby the cross-link  52  follows the swinging translations of the pinion gears  46 ,  47  in a parallel posture relative to the gear  33 . The cross-link  51  has a side cut facing the gear  33  to receive the shaft  49  when the arms  50  and cross-link  52  come into a superimposing relationship with each other. 
   Across the table a mirror image of this double parallelogram linkage is installed on the inner side of the base plate  29  except that two rack gears  53 ,  54  have free ends with no actuator directly connected thereto. Instead, the rack gears  53 ,  54  are driven by an upright molding blade  55  acting as a central mold of a triple mold system of the present invention. 
   As clearly shown in  FIG. 3 , the central blade  55  is shaped like an inverted T made of metal or a comparatively strong composite material and has a corner  56  chamfered at an end and a similar corner  57  at the opposite end. The rack gears  53 ,  54  are attached to the corner  56  as the other rack gear set  32 ,  33  is attached to the corner  57 . The attachments between the rack gears and molding blade  55  may be done through welding or using mechanical fasters, which need boring through the adjacent walls. 
   Extending along the sides of the central blade  55  are a pair of side molding blades  58 ,  59  that are affixed to the cross-links  51 ,  52  of the opposing base plates  28 ,  29  respectively at their ends close to the table  14  so that upon swivel movements of the cross-links  51 ,  52  the side blades  58 ,  59  exert a crimping force laterally as well as vertically against the plate material  13  over the central blade  55  as it moves vertically toward the closing side blades  58 ,  59  resulting in a crimp molding of the ribs  23  from three sides. The ribs  23  will be formed at an even interval along the length of the flat material  13 . 
   Therefore, while the double parallelogram linkage at the side of base plate  28  constitutes a driving side of the molding press  21  the opposing base plate  29  with the mirror image of the mechanism of the driving components becomes a driven end of the press  21  through the molding blades  55 ,  58  and  59 . 
     FIGS. 4A and 4B  are side perspective views for showing more detailed change of state of the molding station between molding and releasing phases with the surrounding components shown partly in schematic. Initially, the longitudinal carriage actuator at  60  for shuttling the first carriage  14  along the rod  17  is at its extended state to which the press actuators  22 ,  26  are timed to stay inactivated where the central blade  55  and side blades  58 ,  59  are free from each other so that the plate material (omitted for simplicity) extends in the open space formed between the central blade  55  and the opposing side blades  58 ,  59 . Additionally, the carriages  14 - 16  are in an open position due to the expansive fasteners  24 , which however limit the distances of the carriages  14 - 16  from each other. So, the carriages  14 - 16  will generally travel as a single body. 
   Also, a pulling cable  61  is attached to the cross-link  52  of the first press  21  at one end and to the adjacent cross-link  51  of the next press  25  at the opposite end for tautening all the carriages  14 - 16  toward each other when the rib forming apparatus  10  is in a molding phase as shown in  FIG. 4B . This is to compensate the longitudinal shrinking of the plate material due to the crimped ribs  23  eliminating any slacks, which may affect the flatness of the final product. The cable  61  is shown loosely connecting the first and second presses  21 ,  25  in their open positions in  FIG. 4A  wherein an end cable  62  similarly connects the second press  25  and the end carriage  16 . The cables  61 ,  62  may be of braided steel wires for both flexibility and durability. 
   Upon retraction of the actuator  60  with simultaneous extensions of the actuators  22 ,  26 , the whole rib forming apparatus  10  slides over the plate material two pitches corresponding to two ribs and their adjacent plate sections back toward its fresh blank section to mold another two ribs at the same time. 
   As soon as the plate material receives new rib crimping at the molding phase of  FIG. 4B , the subsequent extension of the actuator  60  automatically advances the processed plate section one pitch followed by another retraction of the actuator  60  for the next rib molding. Meanwhile, the plate material is held from moving backward with the assist of a simple angled stick (not shown) fixed to an output area of the table  11  for catching the ribs one way. 
   Referring to  FIGS. 5 ,  6 A and  6 B, the method of forming ribs  23  on plastic plate  13  by using the present apparatus  10  is described.  FIG. 5  shows the positioning of the two heaters  20  with suspended heat cores  63  under which upward bends  64  of the plate  13  are initiated during a thermal deformation that also softens the plate  13  in preparation for the subsequent hot clamp-molding step. For a set pitch of the ribs, the distance of the heaters  20  from each other and the first press  21  is firmly determined considering the shrinking length of the plate by the right-angled sidewalls and the connecting bends which amount to two adjacent ribs  23 . Therefore, the distance between the heaters  20  is correspondingly longer than the distance between two adjacent ribs  23 . Whereas, the distance between the longitudinal centers of the presses  21 ,  25  become the pitch of the ribs  23 . Thus, the pitch may be modified by adding the distance between the presses  21 ,  25  with the use of a spacer affixed to one of the base plates at its abutting side and correspondingly increasing the distance between the heaters  20 . 
   In  FIG. 6A , as rack gears  32 ,  34  switch from their extended to retracted positions along with the central blade  55  swinging the side blades  58 ,  59  apart, they are transported back to the molding position shown from where they had released the last rib  23 .  FIG. 6B  depicts the moment when the presses are closed at the exact positions coinciding the pitch of the ribs that can be compared to the longer distance between the two open presses in  FIG. 6A . With the ribs closed in the presses they will advance all together to output the finished plate section pulling the next hot bends  64  of the plate  13  toward the molding positions. 
     FIGS. 7A and 7B  are side views of a press station according to a third embodiment of a rib forming apparatus  100  of the present invention oriented vertically. By having the entire apparatus  100  turned with appropriate frame modification to support this way, it requires only little area to set up the lengthy apparatus. Changing the direction of advancement of the plate material  13  brings the advantage of gravity effect of naturally straightening the finished plate. In this orientation, the rib forming apparatus  100  may be installed as a vertical end unit to a bigger plastic processing plant. The detailed movements of the components remain unchanged. 
     FIG. 8  is a side view of a rib forming apparatus  200  according to a second embodiment of the present invention having an extended bed area  211  to flatten the unreeled web material  13  before processing. The remaining parts of the apparatus  200  are unchanged from the first embodiment. 
     FIG. 9  is a partly cross sectional front view of the rib forming apparatus  200  of  FIG. 8  with heaters  20  removed to show the molding press assembly comprising support table  11 , parallel rods  17  fixed to table  11 , and press  21  having base plates  28 ,  29  mounted on opposite ends of carriage  14 , which is in turn mounted on parallel rods  17 . Actuator  22  will move rack  32  and pinion  40 ,  41  gears to close and open molding blades  55 ,  58  to and from plate material  13 . 
   A second actuator  222  similar to actuator  22  may be installed at its opposite side to double the power of the molding press  21  when the rib forming apparatus needs to process a thicker plate material. 
   Referring to  FIGS. 10 and 11 , one example of the product manufactured by the present rib forming apparatus will be described. 
   Barrier sheet  1  may be used a sleeve for limiting the growth of a root of tree  2 . The barrier sheet  1  has a constant thickness of approximately one-sixteenth of an inch. One available width of the sheet  1  is eighteen inches, but twelve, twenty-four, thirty-six and forty-eight inch sizes can also be produced by the present rib forming apparatus without departing from the principle of the present invention. Those widths become the depth of the barrier at installation on a landscape site. 
   The sheet  1  has a built-in modular feature which allows for cutting and joining any combination of sheet sections to alter the diameter of the root barrier to fit any particular tree size. 
   For the root barrier material, the sheet  1  is preferably of polyethylene, and the substitute material polystyrene can also be used. Long-lasting materials such as resin tiered graphite laminates, plastic molded and extruded materials such as PVC, polyethylene, polystyrene, and polypropylene are also suitable. Thin metal sheet material can also be used. 
   The sheet  1  consists of rectangular flat areas  3  once the sheet is cut and assembled into a root barrier. Across the two longitudinal edges of the sheet are vertical folds  4 , which appear at an even interval throughout the length of the sheet  1 . The length of the interval between the folds  4  is typically five inches, but can be altered as desired. As shown, the vertical folds  4  are adapted to face the interior of the assembled root barrier. The folds  4  form vanes that are aligned vertically and protrude perpendicularly from the sheet  1 . The vanes  4  redirect roots  2  away from the inner surface of the barrier sheet  1 . As roots grow toward the inside surface of the barrier, the vanes channel the roots downward to provide strength for new plantings. 
   Each of the vertical folds  4  includes three severing lines with two proximal perpendicular bends  5  and a distal U-bend  6  connecting the vertical walls of the fold  4  between the proximal bends  5 . This allows the sheet  1  to be cut at the desired lengths to create the appropriate diameter for the root barrier. An installer crosscuts or snaps the sheet  1  at one edge, leaving an end lip  7  and at the opposite edge forming an end clip  8 . This consequently provides an interlocking gap  9  for closing the sheet into the root barrier  1 . 
   Installation of the root barrier  1  is accomplished by simply wrapping the cut sheet around the tree root being planted, with the vertical folds  4  facing the root  2 . Then the end lip  7  is superimposed on one of the clips  8  and pressed toward each one another by hands. 
   It is to be understood that the present invention is not limited to the sole embodiment describe above, but encompasses any and all embodiments within the scope of the following claims. 
   CALL OUT LIST OF ELEMENTS 
   
       
         1 : Root Barrier 
         2 : Root 
         3 : Flat Area 
         4 : Vane 
         5 : Prominal Bend 
         6 : U-bend 
         7 : End Lip 
         8 : End Clip 
         9 : Interlocking Gap 
         10 : Rib Forming Apparatus 
         11 : Support Table 
         12 : Material Roll 
         13 : Elongated Plate 
         14 : First Carriage 
         15 : Second Carriage 
         16 : End Carriage 
         17 : Rod 
         20 : Heater 
         21 : First Press 
         22 , 26 : Vertical Actuator 
         23 : Rib 
         24 : Expansive Fastener 
         25 : Second Press 
         27 : Control Box 
         28 , 29 : Base Plate 
         30 , 31 : Legs 
         32 , 33 : Rack Gears 
         34 , 35 : Reciprocating Rod 
         38 , 39 : Cross Member 
         40 , 41 : Pinion Gears 
         42 , 43 : Shaft 
         44 , 45 , 44 ′, 45 ′: Bore 
         46 , 47 : Pinion Gear 
         48 , 49 : Shaft 
         50 , 50 ′: Arm 
         51 , 52 : Cross-link 
         53 , 54 : Rack Gears 
         55 : Central Blade 
         56 , 57 : Corner 
         58 , 59 : Side Blade 
         60 : Carriage Actuator 
         61 : Cable 
         62 : End Cable 
         63 : Heater Core 
         64 : Bend 
         100 , 200 : Rib Forming Apparatus 
         211 : Extended Bed 
         222 : Second Actuator