Canopy feed method and apparatus for a trim press

Abstract

The feeding of plastic sheet material to a trim press is carried out utilizing an endless belt conveyor which supports and drives the plastic sheet in a manner which is coordinated with the cycle of drawing of the sheet material into the trim press dies. The surface of the conveyor belt supports the plastic sheet for upward movement with little or no dragging of the sheet material, and the position of the plastic sheet being engaged with the conveyor can be set by an operator utilizing guide plates and guide wheels located at a position near the intake end of the conveyor. The conveyor belt may be driven continuously at a rate corresponding to the rate at which plastic sheet is drawn into the trim press, or in intermittent motion by a motor in a manner that is coordinated with the intermittent feeding of the sheet material into the trim press.

What is claimed is:  
     
         1 . A canopy feed apparatus for a trim press comprising: 
 (a) an endless belt conveyor having a conveyor belt with a top facing side extending from an intake end to a discharge end and a motor connected to the belt to drive the belt, the conveyor mounted adjacent to a trim press to extend upwardly from horizontal from the intake end to the discharge end to feed the trim press with plastic sheet discharged from the discharge end; and    (b) guides mounted at the discharge end of the conveyor to guide plastic sheet discharged from the conveyor into the trim press.    
     
     
         2 . The apparatus of  claim 1  further including a pair of guide wheels in position to selectively press against a plastic sheet supported on a top facing side of the conveyor belt at a position proximate to the intake end of the conveyor and a pair of lateral guide plates in position above the top facing side of the conveyor belt to laterally position an incoming sheet and means for mounting the guide wheels and the guide plates for adjustment of the lateral position of the guide wheels and the guide plates.  
     
     
         3 . The apparatus of  claim 2  wherein the means for mounting the guide wheels and guide plates include at least one mounting bar extending laterally between frame members above the top facing side of the conveyor belt, a clamp for each guide wheel and guide plate mounted for sliding movement on the mounting rod and including a locking mechanism by which the clamp can be locked in a selected lateral position, a guide wheel and a guide plate mounted to each clamp to move therewith in lateral adjustment.  
     
     
         4 . The apparatus of  claim 1  further including means for detecting a plastic sheet extending outwardly from the discharge end of the conveyor belt a selected distance and for controlling the motor of the conveyor to shut off power to the motor when a section of plastic sheet exiting the conveyor extends the selected distance from the discharge end, and for supplying power to the motor to drive the conveyor when the plastic sheet exiting from the conveyor does not extend the selected distance outwardly from the discharge end of the conveyor.  
     
     
         5 . The apparatus of  claim 4  wherein the means for detecting includes a limit switch with a trip rod extending therefrom mounted such that the trip rod is spaced a selected distance from the discharge end of the conveyor in position to be contacted by a section of plastic sheet discharged from the conveyor, the limit switch electrically connected to the motor for the conveyor to shut off power to the motor when a section of plastic sheet is in contact with the trip rod so as to trip the limit switch, and to supply power to the motor to drive the conveyor when the plastic sheet exiting from the conveyor is out of contact with the trip rod.  
     
     
         6 . The apparatus of  claim 4  further including a blower mounted beneath the discharge end of the conveyor to blow air outwardly to push the plastic sheet exiting from the conveyor away from the discharge end of the conveyor.  
     
     
         7 . The apparatus of  claim 1  wherein the conveyor belt is formed of a flexible plastic material having a selected coefficient of friction with regard to plastic sheet material to be supported by the conveyor.  
     
     
         8 . The apparatus of  claim 1  wherein the top facing surface of the conveyor extending at an angle of approximately  300  from horizontal from the intake end to the discharge end of the conveyor.  
     
     
         9 . The apparatus of  claim 1  wherein the guides comprise curved guide rods extending above and below the position of plastic sheet exiting from the discharge end of the conveyor and formed to guide the plastic sheet to a position where it is fed into the trim press.  
     
     
         10 . The apparatus of  claim 9  further including means for adjustably setting the lateral positions of the curved guide rods.  
     
     
         11 . A canopy feed apparatus for a trim press comprising: 
 (a) frame members forming a frame;    (b) an endless belt conveyor mounted to the frame having a conveyor belt with a top facing side extending from an intake end to a discharge end and a motor connected to the belt to drive the belt, the conveyor mounted to the frame to extend upwardly from horizontal from the intake end to the discharge end when the feed apparatus is installed to feed a trim press;    (c) a pair of lateral guide plates positioned above the top facing side of the conveyor belt proximate to the intake end of the conveyor to laterally position an incoming sheet; and    (d) means for mounting the guide plates for adjustment of the lateral position of the guide plates.    
     
     
         12 . The apparatus of  claim 11  including a pair of guide wheels positioned to selectively press against a plastic sheet supported on a top facing side of the conveyor belt at a position proximate to the intake end of the conveyor and means for mounting the guide wheels to the frame for adjustment of the lateral position of the guide wheels.  
     
     
         13 . The apparatus of  claim 12  wherein the means for mounting the guide wheels and guide plates include at least one mounting bar extending laterally between frame members above the top facing side of the conveyor belt, a clamp for each guide wheel and guide plate mounted for sliding movement on the mounting rod and including a locking mechanism by which the clamp can be locked in a selected lateral position, a guide wheel and a guide plate mounted to each clamp to move therewith in lateral adjustment.  
     
     
         14 . The apparatus of  claim 13  further including an air cylinder connected to each guide wheel and responsive to air pressure supplied to the air cylinder to press the guide wheel connected thereto against the top side of the conveyor belt.  
     
     
         15 . The apparatus of  claim 13  wherein there are a pair of mounting bars that extend laterally between frame members above the top facing side of the conveyor belt, the pair of lateral guide plates and guide wheels mounted to the mounting bars for sliding lateral movement adjacent to the top facing side of the conveyor belt.  
     
     
         16 . The apparatus of  claim 11  further including means for detecting a plastic sheet extending outwardly from the discharge end of the conveyor belt a selected distance and for controlling the motor of the conveyor to shut off power to the motor when a section of plastic sheet exiting the conveyor extends the selected distance from the discharge end, and for supplying power to the motor to drive the conveyor when the plastic sheet exiting from the conveyor does not extend the selected distance outwardly from the discharge end of the conveyor.  
     
     
         17 . The apparatus of  claim 16  wherein the means for detecting includes a limit switch with a trip rod extending therefrom mounted such that the trip rod is spaced a selected distance from the discharge end of the conveyor in position to be contacted by a section of plastic sheet discharged from the conveyor, the limit switch electrically connected to the motor for the conveyor to shut off power to the motor when a section of plastic sheet is in contact with the trip rod so as to trip the limit switch, and to supply power to the motor to drive the conveyor when the plastic sheet exiting from the conveyor is out of contact with the trip rod.  
     
     
         18 . The apparatus of  claim 16  further including a blower mounted beneath the discharge end of the conveyor to blow air outwardly to push the plastic sheet exiting from the conveyor away from the discharge end of the conveyor.  
     
     
         19 . The apparatus of  claim 11  wherein the conveyor belt is formed of a flexible plastic material having a selected coefficient of friction with regard to plastic sheet material to be supported by the conveyor.  
     
     
         20 . The apparatus of  claim 11  wherein the top facing surface of the conveyor extending at an angle of approximately 30° from horizontal from the intake end to the discharge end of the conveyor.  
     
     
         21 . The apparatus of  claim 11  wherein the guides comprise curved guide rods extending above and below the position of plastic sheet exiting from the discharge end of the conveyor and formed to guide the plastic sheet to a position where it is fed into the trim press.  
     
     
         22 . The apparatus of  claim 21  further including means for adjustably setting the lateral positions of the curved guide rods.  
     
     
         23 . A canopy feed apparatus for a trim press comprising: 
 (a) frame members forming a frame;    (b) an endless belt conveyor mounted to the frame having a conveyor belt with a top facing side extending from an intake end to a discharge end and a motor connected to the belt to drive the belt; and    (c) means for detecting a plastic sheet extending outwardly from the discharge end of the conveyor belt a selected distance and for controlling the motor of the conveyor to shut off power to the motor when a section of plastic sheet exiting the conveyor extends at least the selected distance from the discharge end, and for supplying power to the motor to drive the conveyor when the plastic sheet exiting from the conveyor does not extend the selected distance outwardly from the discharge end of the conveyor.    
     
     
         24 . The apparatus of  claim 23  including guide wheels in position to selectively press against a plastic sheet supported on a top facing side of the conveyor belt at a position proximate to the intake end of the conveyor and a pair of lateral guide plates in position above the top facing side of the conveyor to laterally position an incoming sheet, and means for mounting the guide wheels and the guide plates to the frame for adjustment of the lateral position of the guide wheels and the guide plates.  
     
     
         25 . The apparatus of  claim 24  wherein the means for mounting the guide wheels and guide plates to the frame includes at least one mounting bar extending laterally between frame members above the top facing side of the conveyor belt, a clamp for each guide wheel and guide plate mounted for sliding movement on the mounting rod and including a locking mechanism by which the clamp can be locked in a selected lateral position, a guide wheel and a guide plate mounted to each clamp to move therewith in lateral adjustment.  
     
     
         26 . The apparatus of  claim 23  wherein the means for detecting includes a limit switch with a trip rod extending therefrom mounted such that the trip rod is spaced a selected distance from the discharge end of the conveyor in position to be contacted by a section of plastic sheet discharged from the conveyor, the limit switch electrically connected to the motor for the conveyor to shut off power to the motor when a section of plastic sheet is in contact with the trip rod so as to trip the limit switch, and to supply power to the motor to drive the conveyor when the plastic sheet exiting from the conveyor is out of contact with the trip rod.  
     
     
         27 . The apparatus of  claim 23  further including a blower mounted beneath the discharge end of the conveyor to blow air outwardly to push the plastic sheet exiting from the conveyor away from the discharge end of the conveyor.  
     
     
         28 . The apparatus of  claim 23  wherein the conveyor belt is formed of a flexible plastic material having a selected coefficient of friction with regard to plastic sheet material to be supported by the conveyor.  
     
     
         29 . The apparatus of  claim 23  wherein the frame is mounted adjacent to a trim press with the top facing surface of the conveyor extending at an angle of approximately 30° from horizontal from the intake end to the discharge end of the conveyor.  
     
     
         30 . The apparatus of  claim 23  further including curved guide rods mounted to the frame and extending above and below the position of plastic sheet exiting from the discharge end of the conveyor and formed to guide the plastic sheet to a position where it may be fed into a trim press.  
     
     
         31 . The apparatus of  claim 30  further including means for adjustably setting the lateral positions of the guide rods.  
     
     
         32 . A method of feeding continuous plastic sheet material to a trim press which trims formed parts from the surrounding plastic sheet comprising: 
 (a) supporting a portion of the plastic sheet to be trimmed on the surface of a conveyor belt of an endless belt conveyor;    (b) operating the conveyor to drive the belt in a direction from an intake end of the conveyor to a discharge end to draw the plastic sheet supported on the conveyor toward the discharge end and to discharge a section of plastic sheet from the discharge end of the conveyor and then stopping the conveyor belt;    (c) allowing the trim press to draw a section of the plastic sheet discharged from the conveyor into the trim press for trimming; and    (d) then again operating the conveyor to draw the plastic sheet material with the conveyor belt to discharge another section of plastic sheet material from the discharge end of the conveyor and then stopping the conveyor belt.    
     
     
         33 . The method of  claim 32  wherein steps (c) and (d) are repeated.  
     
     
         34 . The method of  claim 35  further including guiding the plastic sheet supported on the conveyor belt with guide plates positioned adjacent to lateral side edges of the plastic sheet to laterally locate the plastic sheet on the conveyor in proper position to be fed to the trim press.  
     
     
         35 . The method of  claim 34  further including pressing the plastic sheet against the conveyor belt with guide wheels to hold the plastic sheet in place on the conveyor belt as the conveyor is operated.  
     
     
         36 . The method of  claim 36  further including detecting when a selected length of section of plastic sheet has been discharged from the conveyor during operation of the conveyor and then stopping the conveyor.  
     
     
         37 . A method of feeding continuous plastic sheet material to a trim press which trims formed parts from the surrounding plastic sheet comprising: 
 (a) supporting a portion of the plastic sheet to be trimmed on the surface of a conveyor belt of an endless belt conveyor;    (b) operating the conveyor to drive the belt in a direction from an intake end of the conveyor to a discharge end to draw the plastic sheet supported on the conveyor toward the discharge end and to discharge a section of plastic sheet from the discharge end of the conveyor while allowing the trim press to draw a section of the plastic sheet discharged from the conveyor, and driving the belt at a speed such that the rate at which the plastic sheet is discharged from the conveyor corresponds to the average rate which plastic sheet is drawn into the trim press for trimming.    
     
     
         38 . The method of  claim 37  further including guiding the plastic sheet supported on the conveyor belt with guide plates positioned adjacent to lateral side edges of the plastic sheet to laterally locate the plastic sheet on the conveyor in proper position to be fed to the trim press.  
     
     
         39 . The method of  claim 38  further including pressing the plastic sheet against the conveyor belt with guide wheels to hold the plastic sheet in place on the conveyor belt as the conveyor is operated.