Patent Application
20070272522
1. Field of the Invention
The present invention relates to conveyor belts used in the manufacture of extruded aluminum articles. More particularly the invention relates to a chain driven conveyor wherein the chain is attached to the underside of a conveyor belt. More particularly the invention relates to a chain link useful in conveyor chains that may expand or contract as it passes around a drive sprocket which prevents stretching of the belt and prevents binding which saves energy and operating costs.
2. Related Information
Conventional conveyor belts used in extruded aluminum production consists of a number of successive circular conveyor belts. In the past the conveyor belts were designed to effect conveyance by frictional tension between a felt belt and roller. Such belts often stretch under excessive load. Idle running and slippage are common occurrences due to sole reliance on frictional tension for conveyance. As a result the weight is unevenly distributed on other conveyor belts, worsening the performance of the belts and shortening the service life of the belts. In addition, the extruded aluminum products cannot be arranged neatly which adds to the inconvenience of the operation.
To overcome some of the limitations a sprocket and chain has been added to the underside of the felt belt. When the conveyor belt is not overloaded conveyance is effected by the frictional tension between the belt and the rollers. When the conveyor is overloaded by extruded aluminum product, conveyance is effected by engagement of the chain with the sprockets which prevents stretching of the belt, remarkably prolonging the service life of the belt and raising work efficiency.
The chains are typical of those in the art and include an axle mated round hole in an inner link which joins a round hole in the outer link. This type of chain has a drawback. As the chain goes around the round sprocket in a circular movement, the movement is not smooth due to the difference between the inside and outside diameter of the links. This lack of smoothness increases energy consumption and can stretch the belt at this point.
Briefly the present invention comprises a link which replaces the round axle hole with an oblong hole. The oblong hole allows the axle to slide along the length of the link to compensate for the difference in inner and outer diameter as the link passes around the sprocket. In a chain, a link having an oblong hole is mated with a link having a round hole, i.e., if the inner links have oblong holes the outer links have round holes and if the outer links have oblong holes the inner links have round holes. Alternatively each link can have an oblong hole and a round hole, and when assembled the oblong holes in one link are mated with round holes in the opposite link. A chain is thus formed.
The advantage of the present chain over the existing chain is that the chain axle may be displaced in the oblong in the case of a turning motion, circular or clockwise-counterclockwise conversion of rotation and thus the difference between the inside diameter and outside diameter is eliminated. This eliminates the resistance to motion and ensures smooth movement of the chain and reduces power requirements. In addition the service life of the chain is remarkably prolonged and the effort and expenses for maintenance are reduced.
For a detailed description of the preferred embodiment the reader is directed to accompany FIGURE's in which like components are given like reference numerals. Referring first to
Referring now to
Referring now to
it should be appreciated that the oblong holes 6 and/or the flanges 11 could be located on the outer links 5 instead of the inner links 4. Alternatively each link could have one oblong hole 6 and one round hole 13 as depicted in
The foregoing description of the invention has been directed to a particular preferred embodiment of the present invention for the purposes of explanation and illustration. It will be apparent to those skilled in the art that many modifications and changes in the apparatus may be made without departing from the scope and spirit of the invention. It is therefore intended that the following claims cover all equivalent modifications and variations as fall within the scope of the invention as defined by the claims.
