Patent Number: 
Section: claims

1. A mechanical bucket for separating small material from larger material, the mechanical bucket comprising:a bucket adapted to receive and retain material within the bucket;a roller screen assembly removably secured to a bottom portion of the bucket, wherein material received within the bucket rests on the roller screen assembly when deactivated, the roller screen assembly adapted to separate smaller material from larger material of the material received within the bucket when activated, the smaller material passing through the screen and the larger material remaining in the bucket; anda scraper device coupled to the bucket adjacent to a bottom side of the roller screen assembly, wherein the scraper removes debris from the roller screen assembly. 2. The mechanical bucket of claim 1, wherein the scraper device includes a base portion and a plurality of extensions that extend in a direction transverse to the base portion, the extensions engaging the roller screen to scrape debris from the roller screen. 3. The mechanical bucket of claim 1, wherein the roller screen assembly is adapted to agitate the material within the bucket when the roller screen assembly is activated. 4. The mechanical bucket of claim 3, wherein the roller screen assembly is driven to its operating speed at a predetermined rate when activated. 5. The mechanical bucket of claim 4, wherein the roller screen assembly is driven to a stop from operating speed at a predetermined rate when deactivated. 6. The mechanical bucket of claim 5, wherein the roller assembly when activated operates at a variable rotational speed. 7. The mechanical bucket of claim 1, further comprising a sub-base, the sub-base removably coupled to the bottom portion of the bucket, the sub-base adapted to removably secure the roller screen assembly to the bucket. 8. A material separator comprising:a mechanical bucket defining an inner volume, the mechanical bucket adapted to couple to a vehicle, the mechanical bucket movable between a first location and a second location by use of the vehicle;a roller screen assembly removably secured to a bottom portion of the mechanical bucket, wherein material received within the bucket rests on the roller screen assembly when deactivated, the roller screen assembly adapted to separate smaller material from larger material of the material received within the bucket when activated, the smaller material being passed through the roller screen assembly and deposited at the first location and the larger material remaining in the bucket;a scraper device coupled to the bucket adjacent to a bottom side of the roller screen assembly, wherein the scraper removes debris from the roller screen assembly; anda sub-base removably coupled to the bottom portion of the mechanical bucket, the sub-base adapted to removably secure the roller screen assembly to the bucket. 9. The mechanical separator of claim 8, wherein the roller screen assembly is adapted to agitate the material within the bucket when the roller screen assembly is activated. 10. The material separator of claim 8, further comprising a motor mechanically engaged with the roller screen assembly. 11. The material separator of claim 10, wherein motor is driven to its operating speed at a predetermined rate upon activation. 12. The material separator of claim 11, wherein the motor is driven to a stop from its operating speed at a predetermined rate upon deactivation. 13. The material separator of claim 12, wherein the motor operates the roller screen assembly at a variable rotational speed. 14. The material separator of claim 8, wherein the mechanical bucket is adapted to rotate for dumping the larger material at the second location. 15. A method of using a mechanical bucket for separating smaller material from larger material, the method comprising:receiving material within a mechanical bucket, the material including smaller material and larger material;moving the mechanical bucket to a location for depositing the smaller material;activating a roller screen assembly of the mechanical bucket to separate the smaller material from the larger material;removing debris from the roller screen assembly with a scraper; anddepositing the smaller material at the location, wherein the smaller material during separation passes through the roller screen assembly and is deposited at the location. 16. The method of claim 14, further comprising agitating the material to facilitate separation of the smaller material from the larger material. 17. The method of claim 14, further comprising retaining the larger material within the mechanical bucket. 18. The method of claim 14, further comprising deactivating the roller screen assembly when separation of the smaller material from the larger material is completed. 19. The method of claim 14, further comprising:moving the mechanical bucket to a second location; anddumping the larger material in the second location by rotating the bucket.