Selective vacuum lifting device
AssigneePPG Industries, Inc.
InventorWilliam P. Cathers
Life of this patent
Estimating the term…
Abstract
A vacuum lifting device having a plurality of chambers, each chamber having an isolating member within to control communication between a common vacuum plenum and a sheet engaging surface. Each isolating member is controllable independent of the presence of an article adjacent the sheet engaging surface to allow for lifting selected ones of a plurality of articles. Those chambers which overlie at least a portion of a selected article and which overlie no portion of an unselected article are activated, or, alternatively, those chambers which overlie a single selected article completely within the peripheral boundaries thereof are activated.
Claims10
An apparatus for transferring articles, comprising:
- a chamber having apertured wall portions to provide communication between chamber interior and environment;
- a first opening providing communication between vacuum means and the chamber interior;
- a second opening between said first opening and said apertured wall portions providing communication between the chamber interior and the environment;
- first means pivotly mounted within the chamber interior for isolating said second opening and said apertured wall portions from said first opening;
- second means mounting said chamber to overlay said second opening for isolating the chamber interior from the environment when said second isolating means is in a closed position;
- means for biasing said second isolating means toward the closed position;
- means acting on said first isolating means for moving said first isolating means to a first position to interconnect said first opening and said apertured wall portions and into a second position to isolate said apertured wall portions from said first opening;
- and
- said first isolating means pivoting into the second position acts on said second isolating means to urge said first isolating means against said biasing means to move said second isolating means out of the closed position to interconnect the chamber interior to the atmosphere by way of the second opening as said first isolating means isolates the first opening from said apertured wall portion.
A method of transferring at least one article, comprising the steps of:
- providing a chamber having apertured wall portions to provide communication between the chamber interior and the environment;
- a first opening for providing communication between vacuum means and the chamber interior and a second opening between the first opening and the apertured wall portions to provide communication between the chamber interior and the environment;
- first means mounting the chamber to overlay the second opening for isolating the chamber interior from the environment when the first isolating means is in a first position;
- means for biasing the first isolating means toward the first position;
- and second means pivotly mounted within the chamber interior for isolating the first isolating means and the apertured wall portions from the first opening;
- energizing the vacuum means to draw a vacuum through the chamber interior;
- moving the second isolating means to a first position to interconnect the first opening and the apertured wall portions;
- biasing an article toward the apertured wall portions by the vacuum in the chamber interior;
- moving the chamber to move the article;
- moving the second isolating means into a second position to isolate the apertured wall portions from said first opening, wherein the second isolating means pivoting into the second position acts on the first isolating means to urge the first isolating means against the biasing means to move the first isolating means away from the closed position to interconnect the chamber interior to the environment as said second isolating means isolates the first opening from the apertured wall portions to release the article.
Dependencies are inferred from the claim text.