Plastic Bag Opener

Abstract

The present invention is a device for opening plastic bags, such as produce bags at the grocery store. Since those bags are made of very thin plastic, they can often be hard to open, and consumers have to lick their fingers to increase friction enough to unstick the two layers of plastic from each other and open the bag. The present invention obviates the need to lick one's fingers, providing a high-friction wheel with an irregular shape that intermittently contacts a protrusion. The wheel may be turned by means of a handle, or by means of a motor connected to a motion detector. If a plastic bag is inserted into the gap between the high-friction wheel and the protrusion, the bag will open, since the high-friction wheel will slide the top layer of plastic with respect to the bottom layer of plastic. Such a device may be mounted near a plastic bag dispenser at the grocery store or on a shopping cart, so that consumers do not need to remember to bring along yet another gadget.

1 . A device for opening plastic bags, comprising:
 a shelf attached to a base;   a high-friction wheel free to rotate around an axle;   wherein the high-friction wheel is not a perfect circle;   wherein the high-friction wheel comprises at least one location on its outer edge located at a maximum distance from the axle, and at least one location on its outer edge located at a minimum distance from the axle;   a handle connected to the high-friction wheel in a way that enables the wheel to be turned by turning the handle;   wherein the shelf comprises a protrusion, wherein the protrusion is configured in such a way as to come into contact with the at least one location on the outer edge of the high-friction wheel located at a maximum distance from the axle;   wherein the protrusion is configured in such a way as to create a gap between the protrusion and the at least one location on the outer edge of the high-friction wheel located at a minimum distance from the axle;   wherein the surface of the protrusion is rough.   
     
     
         2 . The device of  claim 1 , wherein the high-friction wheel is oval. 
     
     
         3 . The device of  claim 1 , wherein the axle has a hexagonal cross-section and wherein the high-friction wheel is made of an elastic material and comprises an inner diameter that is slightly smaller than a distance from opposite vertices of the hexagonal cross-section of the axle, such that the high-friction wheel deforms when the axle is inserted into the high-friction wheel. 
     
     
         4 . The device of  claim 1 , wherein the high-friction wheel comprises a plurality of points located at a maximum distance from the axle and a plurality of points located at a minimum distance from the axle. 
     
     
         5 . The device of  claim 1 , wherein the high-friction wheel is made of rubber. 
     
     
         6 . The device of  claim 1 , wherein the high-friction wheel comprises a coating of a high-friction material. 
     
     
         7 . The device of  claim 1 , wherein the protrusion has a rough surface. 
     
     
         8 . The device of  claim 1 , wherein the protrusion is made of plastic. 
     
     
         9 . The device of  claim 1 , wherein the protrusion has a rounded cross-section. 
     
     
         10 . The device of  claim 1 , wherein the protrusion is a semi-cylinder, wherein the axis of the semi-cylinder is roughly parallel to the axle. 
     
     
         11 . The device of  claim 1 , wherein the shelf further comprises at least one sloping surface, wherein an outer edge of the shelf is lower than an area immediately adjacent to the protrusion. 
     
     
         12 . The device of  claim 11 , further comprising a second sloping surface wherein a second outer edge of the shelf is lower than an area immediately adjacent to the protrusion. 
     
     
         13 . A method for opening plastic bags, comprising;
 providing a device according to  claim 1 ;   inserting a plastic bag into the gap between the high-friction wheel and the protrusion;   rotating the high-friction wheel in such a way as to draw the plastic bag into contact with the high-friction wheel and the protrusion;   opening the plastic bag by rotating the high-friction wheel;   removing the opened plastic bag.