Title:
MULTIPURPOSE BUCKET FOR HEAVY-DUTY CONSTRUCTION EQUIPMENT
United States Patent 3795070
Abstract:
The multipurpose bucket for loaders, mounted on suitably actuated, commonly known, lift arms and being tilted by actuator cylinders mounted to the arms and to the bucket, comprises a bowl; an extendible bottom which is slidable forwardly and rearwardly with respect to said bowl, and being connected at the rearwardmost terminal end by a connector bar; and an actuator assembly including a bell crank upstandingly, pivotally mounted at its vertex to the rearwardmost terminal side of the bowl, an actuator cylinder mounted in alignment with and over the bell crank to the rearwardmost side of the bowl and pivotally mounted by its piston to the upper arm portion of the bell crank, the lower arm portion of the bell crank being pivotally secured to the connector bar.
US Patent References:
Scoop and loader attachment for tractors
Kohorst et al. - August 1962 - 3048292
Obstruction responsive root cutting plow
Jennings - October 1952 - 2614476
EJECTOR AND FLOOR ACTUATING MEANS FOR SCRAPER
Siewert et al. - July 1972 - 3675347
Ejector mechanism for self-loading scraper
Hermiz et al. - June 1967 - 3325925
Scoop and loader attachment for tractors
Kohorst et al. - August 1962 - 3048292
Obstruction responsive root cutting plow
Jennings - October 1952 - 2614476
EJECTOR AND FLOOR ACTUATING MEANS FOR SCRAPER
Siewert et al. - July 1972 - 3675347
Ejector mechanism for self-loading scraper
Hermiz et al. - June 1967 - 3325925
Inventors:
Bronson, Orville P. (Boise, ID)
Crabtree Sr., Bruce L. (Snohomish, WA)
Crabtree Sr., Bruce L. (Snohomish, WA)
Application Number:
05/340623
Publication Date:
03/05/1974
Filing Date:
03/12/1973
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
414/722, 37/904, 299/37.100, 37/446
International Classes:
E02F3/40; E02F3/76
Field of Search:
37/117.5,4,120,124,126R,129,126AB,126AE,141R,141T,DIG.18 172/801,802 214/131,141,145,78 299/36,37
Primary Examiner:
Wright Jr., Ernest T.
Assistant Examiner:
Eickholt, Eugene H.
Attorney, Agent or Firm:
Kraft, John W.
Parent Case Data:
REFERENCE TO OTHER APPLICATION:
This is a continuation-in-part application of copending application of Orville P. Bronson and Bruce L. Crabtree, Sr. for Heavy Duty Construction Equipment, Ser. No. 234,355, filed Mar. 13, 1972 now abandoned.
Claims:
We claim
1. A multipurpose bucket for loaders, being mounted on suitably actuated lift arms, abd neing tilted by pressure cylinders mounted to said arms and said bucket comprising:
2. The apparatus of claim 1 wherein said teeth are carried between said lower ground-contacting side of said bowl U-shaped wall and a bucket bottom which is coextensive with and disposed distally parallel above said lower ground-contacting side of said bowl U-shaped wall and which is fastened to said bowl.
3. The apparatus of claim 2 wherein said dump plate is fabricated of a closedwork plate material.
4. The apparatus of claim 2 wherein said dump plate is fabricated of an openwork grating.
1. A multipurpose bucket for loaders, being mounted on suitably actuated lift arms, abd neing tilted by pressure cylinders mounted to said arms and said bucket comprising:
2. The apparatus of claim 1 wherein said teeth are carried between said lower ground-contacting side of said bowl U-shaped wall and a bucket bottom which is coextensive with and disposed distally parallel above said lower ground-contacting side of said bowl U-shaped wall and which is fastened to said bowl.
3. The apparatus of claim 2 wherein said dump plate is fabricated of a closedwork plate material.
4. The apparatus of claim 2 wherein said dump plate is fabricated of an openwork grating.
Description:
FIELD OF THE INVENTION
The present invention relates to excavating apparatus and more particularly to a bucket having a selectively extendible bottom for loaders and the like.
DESCRIPTION OF THE PRIOR ART
Material loaders are well-known in their various embodiments, and the bucket portions thereof are also well-known. Among the characteristics of buckets of the prior art is that teeth for breaking material ahead of the bucket have been fixedly mounted members. This has important effects on the operation of the loader. Operations must be suspended for installation or removal of teeth from the bucket, if teeth may be installed on the bucket at all. Although various lengths of teeth have been advantageously associated with different types of jobs and field conditions, installation has been limited to "universal" length teeth. To provide a multiplicity of sets of digging teeth, which would require such elaborate preparations, would be to defeat the general-purpose character of the loader. It is also well-known that the conditions, not only differ between jobs, but also within portions of jobs. Thus, more rapid fixibility is required in the breaking capability aspect of the bucket.
It is also a characteristic of loaders that they are employed in activities in addition to material excavating and handling. They are used as lifts to name one. In this latter activity a broader bucket bottom is required, than is provided in an excavating bucket. Either the bucket must be changed for a lift, or considerable skill and risk must be used to employ the loader as a lift. It should also be noted that in some excavating and material handling activities a longer bucket bottom would be useful. Buckets of the prior art are dominated by fixed dimensional structures.
Accordingly, it is an object of this invention to provide a selectively extendible support portion issuing from the forward edge of the lower ground-contacting side of the bucket.
It is an object to provide selectively controllable actuator means for a substantially infinite number of positions between full extension and full retraction of the aforesaid support.
It is a further object to provide selectively extendible dump plate as the aforesaid support to project from the forward edge of the lower ground-contacting side of the bucket.
It is another object of this invention to provide selectively extendible teeth as the aforesaid support.
It is an object that the aforesaid extendible dump plate be fabricated of a closedwork plate material.
It is an object that the aforesaid extendible dump plate alternatively be an openwork grating.
These and other objects shall become apparent from the description following, it being understood that modifications may be made without affecting the teachings of the invention here set out.
SUMMARY OF THE INVENTION
The multipurpose bucket for loaders, mounted on suitably actuated, commonly known, lift arms and being tilted by actuator cylinders mounted to the arms and to the bucket, generally comprises a bowl; an extendible bottom which is slidable forwardly and rearwardly with respect to said bowl, and being connected at the rearwardmost terminal end by a connector bar; and an actuator assembly including a bell crank upstandingly, pivotally mounted at its vertex to the rearwardmost terminal side of the bowl, an actuator cylinder mounted in alignment with and over the bell crank to the rearwardmost side of the bowl and pivotally mounted by its piston to the upper arm portion of the bell crank, the lower arm portion of the bell crank being pivotally secured to the connector bar. The bucket may also include a further embodiment having a similar bowl and actuator assembly as those set out above, and extendible teeth which are carried and connected in a manner similar to the extendible bottom above.
A more thorough and comprehensive understanding may be had from the detailed description of the preferred embodiment when read in connection with the drawings forming a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a right side elevational view of the multipurpose bucket shown mounted on a front-end loader in broken lines for illustrative purposes.
Fig. 2 is a right front perspective view of the multi-purpose bucket shown with the right side wall and bucket bottom wall broken away to expose the structure of the bucket bottom and a portion of the rear wall broken away to illustrate the actuator assembly.
FIG. 3 is a cross-sectional view taken substantially along the lines 3--3 of the FIG. 2 illustrating the interior configuration thereof, and actuator shown in solid and broken lines to illustrate typical operating positions thereof.
FIG. 4 is a right front perspective view of a further embodiment of the multipurpose bucket shown with the right side wall and bucket bottom wall broken away to expose the structure of the bucket bottom and a portion of the rear wall broken away to illustrate the actuator assembly in its extended actuated position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and more particularly to the FIG. 1, the multipurpose bucket for heavy-duty construction equipment of this invention is shown to advantage and generally identified by the numeral 10. The bucket 10 is generally carried on a suitable tractor vehicle, such as a commonly known front-end loader 11. The bucket 10 is selectively raised and lowered on pivotally mounted arms 12 by hydraulic bucket-raising cylinders (not shown) which are mounted to the loader 11 and the arms 12. The bucket 10 is pivotally tilted with respect to the arms 12 by means of hydraulic bucket-tilting cylinders 13 mounted on the upper terminal side of the arms 12 and to the rearwardmost terminal side of the bucket 10. In this way and through various manipulations of the raising cylinders (not shown) and tilting cylinders 13, material may be accumulated in the bucket 10.
Referring to the FIGS. 2 and 3, the multipurpose bucket 10 comprises a bucket bowl 15, extendible bottom 16, and an actuator assembly 17 for actuating the bottom 16 with respect to the bowl 15. The bowl 15 is an enclosure in which material may be accumulated. The bowl 15 comprises a substantially U-shaped wall 18 and a pair of opposing side walls 19 fastened at each of the terminal ends of the wall 18. The bowl 15, as is typical of most buckets, is pivotally mounted to the forwardmost terminal ends of the arms 12, so as to project the U-shaped wall 18 parallel to the ground. The lower, or ground-contacting, side 18' of the U-shaped wall 18 is flatter and extends further from the geometrical base of the wall 18 of the opposing side to facilitate accumulation and retention of material in the bowl 15. This lower side 18' of the wall 18 may be provided with a coextensively carried cutting bit 20 which projects distally forward of the leading edge of the side walls 19.
The extendible bottom 16 includes a selectively actuated dump plate 16'. The extendible dump plate 16' rides frictionlessly, and is slidably carried transversely by means of guide sleeves 23 disposed, between the uppermost terminal side of the lower wall 18' of the U-shaped wall 18 and a bucket bottom wall 22. The bucket bottom wall 22 is carried on the uppermost terminal side of the guide sleeves 23 distally above and substantially coextensive with the lower wall 18'. The bucket bottom wall 22 may be fastened to the side walls 19 and the forwardmost terminal side of the U-shaped portion of the U-shaped wall 18. The guide sleeves 23 are fastened at their lowermost terminal sides to the uppermost terminal side of the lower wall 18', and their terminal ends are fastened to the side walls 19. It has also been found to advantage to provide guide channels 23' which are disposed rectilinearly on the uppermost terminal side of the lower wall 18' to provide additional support to the extendible bottom 16, and which permits travel of the dump plate 16' transversely with respect to the lower wall 18'. It is to be understood that the bucket bottom wall 22, side walls 19, guide sleeves 23, and guide channels 23' may be suitably fastened to the U-shaped wall 18 by a variety of means, such as welding. The extendible bottom 16 is provided with an actuator assembly connector arm 24 perpendicularly disposed centrally at the rearwardmost terminal edge of the dump plate 16'. The length of the extendible bottom 16 and the actuator connector arm 24 is sufficient to project the plate's 16' forwardmost terminal end distally forward from the bit 20 of the U-shaped wall 18, when the connector arm 24 and the plate 16' are driven forward by the actuator assembly 17, hereinafter described. The guide sleeves 23, channels 23', and the bucket bottom wall 22 may also provide protection for the extendible bottom 16 from impacts and foreign material.
The actuator assembly 17 is operable to move the extendible bottom 16 with respect to the bowl 15. The actuator assembly 17 comprises a bell crank 25 and a pressure cylinder 26. The bell crank 25 is provided with a pair of angularly disposed arm portions 25' and 25". The bell crank 25 is upstandingly, pivotally fastened at the vertex of the arm portions 25' and 25" on a pivot 27 which is fastened to the rearward side of the U-portion of the U-shaped wall 18. The cylinder 26 may be a suitably controlled hydraulic cylinder, and is mounted upstandingly and aligned over the bell crank 25 to the rearward side of the wall 18. A piston rod 26' of the cylinder 26 is pivotally secured to the terminal end of the upper arm portion 25'. The lower arm portion 25" is pivotally secured to the actuator connector arm 24. It may be seen that the cylinder 26 may be double acting. It has been found to advantage to provide a slotted hole 28 rectilinearly in the arm portion 25", in which a pivot pin 24' of the arm 24 may slide to maintain alignment of the bottom 16 over the arcuate travel of the terminal end of the arm portion 25". It has also been found to advantage to provide a slot 24" centrally disposed distally above the lower wall 18' in the U-portion of the U-shaped wall 18 so as to allow forward and rearward movement of the connector arm 24 in response to the actuator assembly 17.
It may be seen that the extendible bottom 16 is operable to increase the accumulative capability and the volume of the bucket 10. It may also be seen that the extendible bottom 16 may permit uses of the loader 11 and bucket 10 beyond mere material handling to include such activities as container handling. The dump plate 16' may be a closedwork plate or an openwork plate, such as a grating.
In operation, the bucket 10 may be raised and dumped as set out above. Should additional breaking capacity be required, the bottom 16 may be selectively extended by extending the piston rod 26' of the cylinder 26. Likewise, the bottom 16 may be retracted distally rearwardly of the forwardmost terminal edge of the cutting bit 20 distally below and coextensive with the bucket bottom 22.
Referring now to the FIG. 4, a further embodiment of the bucket 10 includes a selectively extendible fork-like bottom plate 29 comprising a plurality of substantially parallelly disposed teeth 30 at its forwardmost terminal end and a dump plate 31 at its rearwardmost terminal end. The bucket 10 includes a bowl 15 and actuator assembly 17 which are identical to the bowl 15 and actuator assembly 17 set out above. The extendible fork-like bottom plate 29 and teeth 30 ride frictionlessly between a lower wall 18' of the U-shaped wall 18 and a bucket bottom 22 by guide sleeves 23 and channels 23' which are substantially similarly disposed and connected, as set out above. The fork-like bottom plate 29 is also provided with an actuator connector arm 24, and is operable to travel forwardly and rearwardly with respect to the bowl 15 through a slot 24' centrally disposed in the rearwardmost portion of the U-shaped wall 18 in a similar manner as set out above. As with the extendible bottom 16, the distance from the forwardmost terminal end of the teeth 30 to the forwardmost terminal end of the dump plate 29' is suitable to project the teeth 30 from the forward edge of the bowl 15 when the rearward edge of the plate 29' is distally forward from the U-portion of the U-shaped wall 18 and to be fully retracted when the plate 29' is actuated rearwardly by the assembly 17 and is adjacent the U-portion of the U-shaped wall 18. The dump plate 29' may be extended or retracted by appropriately extending or retracting the cylinder 26.
Having thus described in detail a preferred apparatus which embodies the concepts and principles of the invention and which accomplishes the various objects, purposes and aims thereof, it is to be appreciated and will be apparent to those skilled in the art that many physical changes could be made in the apparatus without altering the inventive concepts and principles embodied therein. Hence, it is intended that the scope of the invention be limited only to the extent indicated in the appended claims.
The present invention relates to excavating apparatus and more particularly to a bucket having a selectively extendible bottom for loaders and the like.
DESCRIPTION OF THE PRIOR ART
Material loaders are well-known in their various embodiments, and the bucket portions thereof are also well-known. Among the characteristics of buckets of the prior art is that teeth for breaking material ahead of the bucket have been fixedly mounted members. This has important effects on the operation of the loader. Operations must be suspended for installation or removal of teeth from the bucket, if teeth may be installed on the bucket at all. Although various lengths of teeth have been advantageously associated with different types of jobs and field conditions, installation has been limited to "universal" length teeth. To provide a multiplicity of sets of digging teeth, which would require such elaborate preparations, would be to defeat the general-purpose character of the loader. It is also well-known that the conditions, not only differ between jobs, but also within portions of jobs. Thus, more rapid fixibility is required in the breaking capability aspect of the bucket.
It is also a characteristic of loaders that they are employed in activities in addition to material excavating and handling. They are used as lifts to name one. In this latter activity a broader bucket bottom is required, than is provided in an excavating bucket. Either the bucket must be changed for a lift, or considerable skill and risk must be used to employ the loader as a lift. It should also be noted that in some excavating and material handling activities a longer bucket bottom would be useful. Buckets of the prior art are dominated by fixed dimensional structures.
Accordingly, it is an object of this invention to provide a selectively extendible support portion issuing from the forward edge of the lower ground-contacting side of the bucket.
It is an object to provide selectively controllable actuator means for a substantially infinite number of positions between full extension and full retraction of the aforesaid support.
It is a further object to provide selectively extendible dump plate as the aforesaid support to project from the forward edge of the lower ground-contacting side of the bucket.
It is another object of this invention to provide selectively extendible teeth as the aforesaid support.
It is an object that the aforesaid extendible dump plate be fabricated of a closedwork plate material.
It is an object that the aforesaid extendible dump plate alternatively be an openwork grating.
These and other objects shall become apparent from the description following, it being understood that modifications may be made without affecting the teachings of the invention here set out.
SUMMARY OF THE INVENTION
The multipurpose bucket for loaders, mounted on suitably actuated, commonly known, lift arms and being tilted by actuator cylinders mounted to the arms and to the bucket, generally comprises a bowl; an extendible bottom which is slidable forwardly and rearwardly with respect to said bowl, and being connected at the rearwardmost terminal end by a connector bar; and an actuator assembly including a bell crank upstandingly, pivotally mounted at its vertex to the rearwardmost terminal side of the bowl, an actuator cylinder mounted in alignment with and over the bell crank to the rearwardmost side of the bowl and pivotally mounted by its piston to the upper arm portion of the bell crank, the lower arm portion of the bell crank being pivotally secured to the connector bar. The bucket may also include a further embodiment having a similar bowl and actuator assembly as those set out above, and extendible teeth which are carried and connected in a manner similar to the extendible bottom above.
A more thorough and comprehensive understanding may be had from the detailed description of the preferred embodiment when read in connection with the drawings forming a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a right side elevational view of the multipurpose bucket shown mounted on a front-end loader in broken lines for illustrative purposes.
Fig. 2 is a right front perspective view of the multi-purpose bucket shown with the right side wall and bucket bottom wall broken away to expose the structure of the bucket bottom and a portion of the rear wall broken away to illustrate the actuator assembly.
FIG. 3 is a cross-sectional view taken substantially along the lines 3--3 of the FIG. 2 illustrating the interior configuration thereof, and actuator shown in solid and broken lines to illustrate typical operating positions thereof.
FIG. 4 is a right front perspective view of a further embodiment of the multipurpose bucket shown with the right side wall and bucket bottom wall broken away to expose the structure of the bucket bottom and a portion of the rear wall broken away to illustrate the actuator assembly in its extended actuated position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and more particularly to the FIG. 1, the multipurpose bucket for heavy-duty construction equipment of this invention is shown to advantage and generally identified by the numeral 10. The bucket 10 is generally carried on a suitable tractor vehicle, such as a commonly known front-end loader 11. The bucket 10 is selectively raised and lowered on pivotally mounted arms 12 by hydraulic bucket-raising cylinders (not shown) which are mounted to the loader 11 and the arms 12. The bucket 10 is pivotally tilted with respect to the arms 12 by means of hydraulic bucket-tilting cylinders 13 mounted on the upper terminal side of the arms 12 and to the rearwardmost terminal side of the bucket 10. In this way and through various manipulations of the raising cylinders (not shown) and tilting cylinders 13, material may be accumulated in the bucket 10.
Referring to the FIGS. 2 and 3, the multipurpose bucket 10 comprises a bucket bowl 15, extendible bottom 16, and an actuator assembly 17 for actuating the bottom 16 with respect to the bowl 15. The bowl 15 is an enclosure in which material may be accumulated. The bowl 15 comprises a substantially U-shaped wall 18 and a pair of opposing side walls 19 fastened at each of the terminal ends of the wall 18. The bowl 15, as is typical of most buckets, is pivotally mounted to the forwardmost terminal ends of the arms 12, so as to project the U-shaped wall 18 parallel to the ground. The lower, or ground-contacting, side 18' of the U-shaped wall 18 is flatter and extends further from the geometrical base of the wall 18 of the opposing side to facilitate accumulation and retention of material in the bowl 15. This lower side 18' of the wall 18 may be provided with a coextensively carried cutting bit 20 which projects distally forward of the leading edge of the side walls 19.
The extendible bottom 16 includes a selectively actuated dump plate 16'. The extendible dump plate 16' rides frictionlessly, and is slidably carried transversely by means of guide sleeves 23 disposed, between the uppermost terminal side of the lower wall 18' of the U-shaped wall 18 and a bucket bottom wall 22. The bucket bottom wall 22 is carried on the uppermost terminal side of the guide sleeves 23 distally above and substantially coextensive with the lower wall 18'. The bucket bottom wall 22 may be fastened to the side walls 19 and the forwardmost terminal side of the U-shaped portion of the U-shaped wall 18. The guide sleeves 23 are fastened at their lowermost terminal sides to the uppermost terminal side of the lower wall 18', and their terminal ends are fastened to the side walls 19. It has also been found to advantage to provide guide channels 23' which are disposed rectilinearly on the uppermost terminal side of the lower wall 18' to provide additional support to the extendible bottom 16, and which permits travel of the dump plate 16' transversely with respect to the lower wall 18'. It is to be understood that the bucket bottom wall 22, side walls 19, guide sleeves 23, and guide channels 23' may be suitably fastened to the U-shaped wall 18 by a variety of means, such as welding. The extendible bottom 16 is provided with an actuator assembly connector arm 24 perpendicularly disposed centrally at the rearwardmost terminal edge of the dump plate 16'. The length of the extendible bottom 16 and the actuator connector arm 24 is sufficient to project the plate's 16' forwardmost terminal end distally forward from the bit 20 of the U-shaped wall 18, when the connector arm 24 and the plate 16' are driven forward by the actuator assembly 17, hereinafter described. The guide sleeves 23, channels 23', and the bucket bottom wall 22 may also provide protection for the extendible bottom 16 from impacts and foreign material.
The actuator assembly 17 is operable to move the extendible bottom 16 with respect to the bowl 15. The actuator assembly 17 comprises a bell crank 25 and a pressure cylinder 26. The bell crank 25 is provided with a pair of angularly disposed arm portions 25' and 25". The bell crank 25 is upstandingly, pivotally fastened at the vertex of the arm portions 25' and 25" on a pivot 27 which is fastened to the rearward side of the U-portion of the U-shaped wall 18. The cylinder 26 may be a suitably controlled hydraulic cylinder, and is mounted upstandingly and aligned over the bell crank 25 to the rearward side of the wall 18. A piston rod 26' of the cylinder 26 is pivotally secured to the terminal end of the upper arm portion 25'. The lower arm portion 25" is pivotally secured to the actuator connector arm 24. It may be seen that the cylinder 26 may be double acting. It has been found to advantage to provide a slotted hole 28 rectilinearly in the arm portion 25", in which a pivot pin 24' of the arm 24 may slide to maintain alignment of the bottom 16 over the arcuate travel of the terminal end of the arm portion 25". It has also been found to advantage to provide a slot 24" centrally disposed distally above the lower wall 18' in the U-portion of the U-shaped wall 18 so as to allow forward and rearward movement of the connector arm 24 in response to the actuator assembly 17.
It may be seen that the extendible bottom 16 is operable to increase the accumulative capability and the volume of the bucket 10. It may also be seen that the extendible bottom 16 may permit uses of the loader 11 and bucket 10 beyond mere material handling to include such activities as container handling. The dump plate 16' may be a closedwork plate or an openwork plate, such as a grating.
In operation, the bucket 10 may be raised and dumped as set out above. Should additional breaking capacity be required, the bottom 16 may be selectively extended by extending the piston rod 26' of the cylinder 26. Likewise, the bottom 16 may be retracted distally rearwardly of the forwardmost terminal edge of the cutting bit 20 distally below and coextensive with the bucket bottom 22.
Referring now to the FIG. 4, a further embodiment of the bucket 10 includes a selectively extendible fork-like bottom plate 29 comprising a plurality of substantially parallelly disposed teeth 30 at its forwardmost terminal end and a dump plate 31 at its rearwardmost terminal end. The bucket 10 includes a bowl 15 and actuator assembly 17 which are identical to the bowl 15 and actuator assembly 17 set out above. The extendible fork-like bottom plate 29 and teeth 30 ride frictionlessly between a lower wall 18' of the U-shaped wall 18 and a bucket bottom 22 by guide sleeves 23 and channels 23' which are substantially similarly disposed and connected, as set out above. The fork-like bottom plate 29 is also provided with an actuator connector arm 24, and is operable to travel forwardly and rearwardly with respect to the bowl 15 through a slot 24' centrally disposed in the rearwardmost portion of the U-shaped wall 18 in a similar manner as set out above. As with the extendible bottom 16, the distance from the forwardmost terminal end of the teeth 30 to the forwardmost terminal end of the dump plate 29' is suitable to project the teeth 30 from the forward edge of the bowl 15 when the rearward edge of the plate 29' is distally forward from the U-portion of the U-shaped wall 18 and to be fully retracted when the plate 29' is actuated rearwardly by the assembly 17 and is adjacent the U-portion of the U-shaped wall 18. The dump plate 29' may be extended or retracted by appropriately extending or retracting the cylinder 26.
Having thus described in detail a preferred apparatus which embodies the concepts and principles of the invention and which accomplishes the various objects, purposes and aims thereof, it is to be appreciated and will be apparent to those skilled in the art that many physical changes could be made in the apparatus without altering the inventive concepts and principles embodied therein. Hence, it is intended that the scope of the invention be limited only to the extent indicated in the appended claims.