The invention relates generally to power-driven conveyors and more particularly to guides positioned alongside or within a stream of conveyed articles.
Guide walls are often used alongside, across, or within a stream of conveyed articles to guide the articles along a conveyor. Usually the walls have static surfaces along which the articles slide as they are being conveyed. Bead or roller rails, or guides, are used to replace the sliding friction of static guides with lower rolling friction. These low-friction guides are made of hard beads or rollers arranged in stacks on rods. The beads or rollers are free to rotate on the rods when contacted by an advancing article. Often the bead or roller guides are used as stops across a conveyor to divert articles to a side or as side rails along which articles can be registered. Because the beads or rollers are made of a hard material, articles can bounce off the rigid bead or roller on contact. The impact can damage the article or alter its alignment or orientation, which can degrade the transfer to another conveyor downstream.
One version of a conveyor guide wall embodying features of the invention comprises a plurality of columns of one or more rollers mounted between the top and bottom rails. Each of the roller columns is arranged to rotate on parallel axes of rotation. Each of the rollers includes a first side, a second side, and an outer periphery encircling the axis of rotation and extending axially from the first side to the second side. Voids extend through each roller from the first side to the second side between the outer periphery and the axis of rotation to absorb impacts against the outer periphery of the roller.
In another aspect of the invention, a conveyor system embodying features of the invention comprises a conveyor conveying articles in a conveying direction along a conveying plane and a guide wall arranged perpendicular to the conveying plane to contact the articles. The guide wall includes rollers that are rotatable on axes of rotation transverse to the conveying plane and that have outer peripheries to contact the articles. Each of the rollers has a plurality of voids extending through the roller between the axis of rotation and the outer periphery to absorb impacts against the outer periphery of the roller by the articles as they are conveyed in the conveying direction.
A conveyor system embodying features of the invention is shown in
The guide wall 16 comprises columns 18, 19 of stacked rollers 20 mounted between parallel top and bottom rails 22, 23. In this example the rollers 20 in adjacent columns 18, 19 are vertically offset so that they can be interleaved in a high-density pattern. But the rollers could be vertically aligned in a lower-density pattern. Each column 18, 19 of rollers 20 rotates on an axis of rotation 24 that is transverse—in this example, perpendicular—to the conveying plane 26 of the conveyor 10. To increase or decrease the pressure on the conveyor as the articles are conveyed along the guide wall 16, the axes of rotation 24 can be angled forward or rearward in the conveying direction 14—slightly off perpendicular to the conveying plane 26 of the conveyor 10. For small articles a guide wall with only a single roller in each column may suffice. The rollers 20 rotate freely on their parallel axes of rotation 24 and contact the conveyed articles 12 in low-friction, rolling contact.
One version of the rollers 20 is shown in more detail in
The roller columns 18 are shown in more detail in
Although the invention has been described in reference to an exemplary version, other versions are possible. For example, instead of having bushings, the rollers could be molded or machined as a single piece of material with an integral central hub that extends outward from one or both sides to space stacked rollers. As another example, the guide wall can be positioned within a stream of articles, rather than alongside as in