Masking technology

Abstract

The invention provides masking machines for applying masking to glazing panels. Also provided are methods of applying masking to glazing panels.

What is claimed is: 
     
         1 . A method of masking glazing panels using a masking machine having a roller wiper that is simultaneously rotatable about a longitudinal axis of the roller wiper and subject to relative linear motion, with respect to a glazing panel, along a desired axis of the masking machine, the desired axis of the masking machine being crosswise to the longitudinal axis of the roller wiper, the method comprising providing the glazing panel at a masking station of the machine, the glazing panel having opposed front and rear surfaces, the front surface of the glazing panel being oriented toward the roller wiper, providing a masking material having opposed first and second faces, moving the roller wiper toward the glazing panel so as to press the masking material against the glazing panel such that the first face of the masking material is secured to the front surface of the glazing panel, and applying a desired length of the masking material to the glazing panel by rolling the roller wiper along the front surface of the glazing panel, thereby securing the desired length of the masking material to a desired width of the front surface of the glazing panel. 
     
     
         2 . The method of  claim 1  comprising wrapping a leading end of the masking material around a desired circumferential extent of the roller wiper by delivering first and second air streams that blow the leading end of the masking material around the desired circumferential extent of the roller wiper, the first and second air streams being directed respectively along first and second axes that are offset from each other by an acute angle. 
     
     
         3 . The method of  claim 2  wherein the masking machine comprises a masking applicator head that is movable relative to the glazing panel, wherein the first air stream is emitted by operating a first nozzle or a row of first nozzles, the second airstream is emitted by operating a second nozzle or a row of second nozzles, the first and second nozzles being part of an air-knife assembly of the masking applicator head, the air-knife assembly being movable independently relative to the roller wiper. 
     
     
         4 . The method of  claim 2  further comprising delivering a third air stream to prevent the leading end of the masking material from touching the glazing panel until said moving of the roller wiper toward the glazing panel, the third air stream being directed along a third axis. 
     
     
         5 . The method of  claim 4  wherein the masking machine comprises a masking applicator head that is movable relative to the glazing panel, wherein the first air stream is emitted by operating a first nozzle or a row of first nozzles, the second airstream is emitted by operating a second nozzle or a row of second nozzles, and the third airstream is emitted by operating a third nozzle or a row of third nozzles, the first and second nozzles being part of an air-knife assembly of the masking applicator head, the air-knife assembly being movable independently relative to the roller wiper, the third nozzle or row of third nozzles being mounted to a second assembly of the masking applicator head, the second assembly being moveable independently relative to the roller wiper. 
     
     
         6 . The method of  claim 4  wherein the third axis is generally parallel to the first surface of the glazing panel. 
     
     
         7 . The method of  claim 1  wherein the masking machine comprises a pre-stretch system, the method comprising actuating the pre-stretch system, before applying said desired length of the masking material to the glazing panel, so as to stretch the masking material to remove wrinkles. 
     
     
         8 . The method of  claim 7  wherein the pre-stretch system comprises a mount to which the masking material is adhered temporarily, the mount having a compact position and an expanded position, wherein said actuating the pre-stretch system comprises moving the mount from its compact position to its expanded position, while the masking material is adhered to the mount, thereby stretching the masking material in a width direction of the masking material. 
     
     
         9 . The method of  claim 8  wherein the mount comprises a flexible elongated strip to which the masking material is adhered temporarily, and wherein said actuating the pre-stretch system comprises stretching the strip so as to further elongate the strip, while the masking material is adhered to the strip, thereby stretching the masking material in the width direction of the masking material. 
     
     
         10 . The method of  claim 1  wherein a roller force of 5-12.5 pounds per inch is used during said rolling of the roller wiper along the first surface of the glazing panel, in combination with subjecting the masking wiper to relative linear motion, with respect to the glazing panel, at a linear speed of 50-130 inches per minute along the desired axis of the masking machine. 
     
     
         11 . The method of  claim 1  wherein the masking machine is automated to switch masking rolls itself by having a series of roll-change devices spaced-apart along a lateral axis of the masking machine, the masking machine comprising a masking applicator head carrying a roll of the masking material, the method further comprising selecting two of the spaced-apart roll-change devices, operating a first of those two roll-change devices such that the machine itself removes the roll of the masking material from the masking applicator head, and thereafter operating a second of those two roll-change devices such that the machine itself mounts a new roll of masking material on the masking applicator head. 
     
     
         12 . The method of  claim 1  wherein the masking machine has an automated sensor that detects the presence of the glazing panel at a position on a lateral axis of the masking machine, wherein the conveyor is operated to move the glazing panel along the lateral axis of the masking machine such that the glazing panel moves to the position whereupon an edge of the glazing panel is detected by the sensor, the sensor being located on an upright platen supporting the rear surface of the glazing panel. 
     
     
         13 . The method of  claim 1  wherein the roller wiper is part of a masking applicator head mounted so as to be moveable along an upright beam that is mounted so as to be moveable horizontally along two horizontal beams, and the method comprises moving the roller wiper together with the masking applicator head along the upright beam and subsequently moving the roller wiper together with the masking applicator head horizontally by moving the upright beam horizontally along the two horizontal beams. 
     
     
         14 . The method of  claim 13  wherein the masking applicator head includes the roller wiper and carries a roll of the masking material, the method comprising unrolling some of the masking material from the roll while simultaneously moving the masking applicator head, including the roller wiper and the roll, horizontally by moving the upright beam horizontally along the two horizontal beams. 
     
     
         15 . The method of  claim 14  wherein, after moving the masking applicator head, including the roller wiper and the roll, horizontally by moving the upright beam horizontally along the two horizontal beams, the method further comprises cutting the desired length of the masking material from the roll. 
     
     
         16 . The method of  claim 1  wherein the masking machine is operated so as to apply a plurality of sequentially overlapped strips of the masking material onto the first surface of the glazing panel by making at least two successive passes of the roller wiper along the front surface of the glazing panel, the glazing panel being a multi-pane insulating glass unit comprising two glass panes. 
     
     
         17 . A method of masking glazing panels using a masking machine having a roller wiper that is simultaneously rotatable about a longitudinal axis of the roller wiper and subject to relative linear motion, with respect to a glazing panel, along a lateral axis of the masking machine, the lateral axis of the masking machine being crosswise to the longitudinal axis of the roller wiper, the method comprising providing the glazing panel at a masking station of the machine, the glazing panel having opposed front and rear surfaces, the front surface of the glazing panel being oriented toward the roller wiper, providing a masking material having opposed first and second faces, the first face of the masking material carrying adhesive, moving the roller wiper toward the glazing panel so as to press the masking material against the glazing panel such that the first face of the masking material is secured adhesively to the front surface of the glazing panel, and applying a desired length of the masking material to the glazing panel by rolling the roller wiper along the front surface of the glazing panel, thereby adhesively securing the desired length of the masking material to a desired width of the front surface of the glazing panel.