Front end loaders are powered vehicles running on wheels or tracks having hydraulically operated upper and lower pairs of arms extending from the front of the vehicle. The arms often operate in tandem in a linked parallelogram arrangement and perform useful work by means of attached implements such as a bucket, scoop, plow, fork, or the like. It is often desirable to change implements and, for this purpose, quick couplers have been developed. Such coupler systems employ a male master mounted on the upper and lower arms of a front end loader adapted for mating engagement with female couplers attached to the various implements. Incorporated herein by reference is U.S. Pat. No. 4,708,579, which fully discloses a hydraulically or manually actuated implement coupler for front end loaders.
A shortcoming of prior systems, especially those using a fork-type implement, is that the object to be engaged cannot be seen by the operator of the front end loader. Often, even the forks themselves are obscured from view by the framework of the implement. Such shortcomings give rise to inefficient operation of the front end loader with such implements by slowing such operations. Additionally, with the operator blinded by the implement itself, damage to items being manipulated by the fork is an ever-present possibility, as is damage to surrounding structure. Accordingly, there is a need in the an for maintaining the strength and durability of present coupler designs, while allowing the operator of the front end loader to see the object to be engaged by the fork or other implement, thus greatly increasing the ease of use of the front end loader with a fork or other similar type attachment while preventing damage to the item to be manipulated.
Since the operator of a front end loader is normally seated behind the coupler and, in normal operations, must look through the coupler to see the load to be engaged by the implement, such as when loading palletized materials with forks, there is a need in the art for a coupler which maximizes visibility to the load and coupler by removing structural members from the required line of sight as much as possible, while maintaining structural integrity. The instant invention provides such a coupler.
USPTO Backgrounds
USPTO Backgrounds