| 主权项 |
1. A container capable of being stacked in a helical stack of like containers, comprising:
a body having a bottom panel which is substantially perpendicular to a stacking axis and further having a top panel axially displaced from the bottom panel, the top panel also being substantially perpendicular to the axis, a front panel of the body disposed between the bottom and top panels and having a noncircular axial cross-section; a first engagement surface formed on a first of the top and bottom panels, the first engagement surface having a plurality of recesses equally horizontally displaced from the axis and each extending in a radial direction, the recesses being equally angularly spaced apart from each other; a second engagement surface formed on the other of the top and bottom panels, the second engagement surface having a plurality of protuberances which are an integral multiple of the number of recesses, the protuberances being equally horizontally displaced from the axis, the protuberances being equally angularly spaced apart from each other; the protuberances being organized into sets equal in number to said integral multiple, the protuberances in any set being spaced apart in angular position by protuberances in the other sets, at least one set of protuberances being angularly displaced relative to the angular position of the recesses by a predetermined angle which is chosen to be greater than zero but less than ninety degrees, such that when the container is stacked on a like, second container, a first engagement surface engages with the second engagement surface, thereby defining a first angular displacement of the front panel of the first container relative to the angular position of the front panel of the second container; and such that when a third container similar to said container is stacked on the first container while the first container is simultaneously stacked on the second container, a first engagement surface of the third container engages the second engagement surface of the first container thereby defining a second angular displacement of the front panel of the second container relative to the angular position of the front panel of the third container, the second angular displacement being preselected to be greater than zero but less than ninety degrees, the second angular displacement not being equal to the first angular displacement. |
