US3680234A

US3680234A - Earth moving vehicle dumping structure

Info

Publication number: US3680234A
Application number: US15475A
Authority: US
Inventors: Thomas H Scott
Original assignee: MRS Manufacturing CO
Current assignee: MRS Manufacturing CO
Priority date: 1970-03-02
Filing date: 1970-03-02
Publication date: 1972-08-01
Anticipated expiration: 1989-08-01

Abstract

A vehicle for excavating earth or other similar material and then transporting same to a site for dumping. The vehicle includes an open ended bowl construction comprised of a pair of side walls, a base wall and a rear wall arrangement. The base wall construction provides the floor area for supporting the earth material, and is defined by a pair of hingedly connected panels movable to an open condition so as to provide a pair of dumping openings on opposite sides thereof. The rear wall arrangement is provided by a rear panel member mounted for both vertical and retractive movement relative to the base wall construction. The vertical movement thus afforded permits the lower portion of the rear wall member to function as a spreader blade during dumping, while the retractive movement facilitates the overall dumping operation.

Description

United States Patent [451 Aug. 1,1972

Scott [54.] EARTH MOVING VEHICLE DUMPING STRUCTURE [72] Inventor: Thomas H. Scott, Jackson, Miss.

' [73] Assignee: M-R-S Manufacturing Company,

Flora, Miss.

[22] Filed: March 2, 1970 [21] Appl. No.: 15,475

[52] U.S. Cl. ..37/129, 37/8, 37/126 AC [51] Int. Cl. ..E02f 3/02 [58] Field of Search ...37/l26, 129, 8

[56] References Cited UNITED STATES PATENTS 3,521,388 7/1970 Simmons ..37/129 3,431,663 3/1969 Eiger ..37/126 R X 3,057,090 10/1962 Mazzarins ..37/126 R 7 3,466,765 9/1969 Bernotas et a1 ..3 7/126 R X 3,235,985 2/1966 Lauster ..37/126 3,108,388 10/1963 Johnson ..37/8 X 3,343,286 9/1967 Ray et al ..37/8

Primary Examiner-Edgar S. Burr Attorney-Olson, Trexler, Wolters & Bushnell [5 7] ABSTRACT A vehicle for excavating earth or other similar material and then transporting same to a site for dumping. The vehicle includes an open ended bowl construction comprised of a pair of side walls, a base wall and a rear wall arrangement. The base wall construction provides the floor area for supporting the earth material, and is defined by a pair of hingedly connected panels movable to an open condition so as to provide a pair of dumping openings on opposite sides thereof. The rear wall arrangement is provided by a rear panel member mounted for both vertical and retractive movement relative to the base wall construction. The vertical movement thus afforded permits the lower portion of the rear wall member to function as a spreader blade during dumping, while the retractive movement facilitates the overall dumping operation.

25 Claims, 7 Drawing Figures PATENTEDMIB 1 m2 sum 1 or 3 EARTH MOVING VEHICLE DUMPING STRUCTURE BACKGROUND OF INVENTION This invention relates to earth moving machines, or the like, and more particularly to an improved bowl construction and mode of operation for a vehicle of the type which planes earth from the surface of the ground and stores same in said bowl for subsequent dumping, wherein dumping is achieved through the bottom wall or floor of said bowl construction.

Conventional earth scraper and dumping apparatus of the general type employing a bottom wall dumping arrangement are known, such as those disclosed in US. Pat. No. 3,343,286, issued Sept. 26, 1967, and in U.S. application Ser. No. 685,009; now U. S. Pat. No. 3,521,388 filed Nov. 22, 1967. With earth scraper machines such as these, an open bowl construction is provided into which earth fill or other materials are loaded. The forward, open end of the bowl has a scraper blade decliningly mounted thereon, such that when it is desired to load the bowl, the front end thereof is lowered to bring said blade into contact with the ground. Accordingly, as the scraper machine is moved forward by a tractor or some other towing apparatus, the blade cuts or planes into the earth causing it to move upwardly into the bowl. In addition, elevator apparatus are often employed in conjunction with said open end of the bowl construction to facilitate the disposition of the earth or earth fill into said bowl.

While the various vehicles and scraper bowl constructions of the prior art, and especially those specifically mentioned above, have proven successful. There is an ever increasing demand for improved structures, that is, structures which are simpler to repair and operate, yet capable of performing in the same manner. or in an improved manner with respect to conventional machines. In this regard, by simplification of the structural arrangement, numerous advantages can be obtained, for example, more rugged, trouble-free operation; simplification of maintenance problems; and reduction in the overall cost of the vehicle.

The ejection arrangements of the prior art devices, with the exception of those taught in the above-mentioned patent and pending application, have not proven satisfactory due to the excessively large scraper bowl used, the intricate and rather costly provisions for unloading and leveling, and the reduction or limitation of available scraper bowl space required for the dumping mechanism.

Accordingly, with the hereinafter to be discussed scraper bowl construction, many of the advantages obtainable with the structures'discussed in the aforementioned patent and pending application can be attained, while other, previously unattainable advantages or improvements will also be realized. In this regard, the present invention provides a bowl construction employing a hingedly mounted rear wall that can be moved both rearwardly and downwardly of the base or bottom wall of the bowl construction to provide an initial dumping opening. The movement of the rear wall can be controlled with regard to both phases so as to vary the size of the initial opening thus produced, and also to vary the degree of downward movement obtained. Concerning this latter point, the lower edge portion of the rear wall may now be used as a spreader or grading blade, thus eliminating the necessity for separate, intricate spreader blade attachments found on the prior art constructions. Also, the present invention provides a novel single fold base wall arrangement and operating apparatus, all of which cooperate to assure that the dumping openings obtainable therewith are properly positioned with respect to the bowl construction so as to assure and facilitate complete dump- Further, concerning the overall arrangement of the bowl construction of the present invention, it should be noted that same is designed such that during dumping the movement of all articulated elements is away from any surface or stationary element against which the earth material can be compressed. In this regard, quite often the earth fill is moist and sticky such that when compressed it will adhere to the surfaces of the bowl, so as to hinder and resist complete ejection from the bowl construction.

The employment of the rear wall arrangement of the present invention is such that the use of a separate grader or leveling attachment, as found on the prior art structures, is eliminated. Thus, the various intricate and costly operating mechanisms employed with the aforementioned separate grader attachments are also done away with, this being done without sacrificing the overall performance of the vehicle. In addition, with the single fold type of base wall arrangement of the present invention, approximately percent of the original, material supporting floor area is removed during the dumping, so as to afford the largest possible dumping opening.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENT FIG. I is a side view of an earth moving vehicle of the present invention, which vehicle is designed to be drawn by a tractor, or the like;

FIG. 2 is a sectional view of the earth moving vehicle of FIG. 1 illustrating the disposition of the vehicle during loading of earth fill material into the bowl construction;

FIG. 3 is a sectional view similar to FIG. 2 and showing the manner in which the rear wall of the bowl construction operates to provide the initial dumping open- FIG. 4 is a sectional view similar to FIGS. 2 and 3 and illustrating how the rear wall may be employed as a spreader, and also illustrating the operation of the novel single fold base wall of the present invention;

FIGS. 5 and 6 are enlarged, fragmentary sectional views of the rear wall arrangement of the present invention and the operating mechanism employed therewith, and illustrating how said wall is retracted and then lowered;

- FIG. 7 is a fragmentary sectional view illustrating the employment of adjustable stop means for regulating the retractive movement of the rear wall.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENT construction 20 by a hinge connection designated generally 22. A pair of power cylinders 24 are provided, each being carried by a side arm 18 or the cross member 16 and having their respective actuator rods 26 pivotally connected to the bowl 20 proximate the front edge of said bowl and on opposite sides thereof. Accordingly, operation of the power cylinders 24 is effective to raise and lower the bowl 20 between the position illustrated in FIG. 1 and that of FIG. 2. Concerning the latter, it can be seen that upon extension of the actuator rods 26, a scraper blade 30 is brought into position for engagement with the soil in preparation for the loading operation.

In addition to the scraper blade 30, the bowl construction 20 further includes a rear frame segment 32 which supports a rear wheel arrangement 34, a pair of spaced side walls 36, a base or bottom wall construction 38 disposed intermediate said side walls 36 and defining the material supporting floor area, and a rear wall 40. Thus, it can be seen that there is provided an open ended structure having a scooplike configuration, which is adapted to contain a substantial quantity of earth fill, sand, gravel, or the like.

The aforementioned pivotal connection of the actuator arms 26 to the bowl 20 is effected adjacent the open front end of the bowl, and proximate the base wall construction 38. While the base wall construction 38 will be described in more detail hereinafter regarding the operation of the scraper vehicle 10, it can be seen from FIG. 2 that the aforementioned scraper blade 30 defines the forward edge portion thereof.

In the illustrated embodiment, the leading or forward edges of the side walls 36 are formed at an acute angle with respect to the base wall construction 38. The slope of these edges is not critical with respect to the present invention, and they are disposed on a bias primarily to accommodate an elevator structure 42.

The elevator structure 42 is operatively positioned with respect to the open forward end of bowl 20 by attachment to the spaced side walls 36. Numerous articulated mounting systems for elevators of this type are known in the art, such as that illustrated in the aforementioned pending application. Accordingly, it is envisioned that any of these may be employed with the vehicle of the present invention; or for that matter, a stationary mounting arrangement may be utilized. Irrespective of the specifics concerning the mounting of elevator 42, or its drive mechanism (not shown), said elevator 42 is comprised primarily of a plurality of spaced apart, horizontally positioned material engaging slats or angle irons 44 carried by a pair of sprocket chains 46 engaged over upper and lower sprocket gear assemblies 47 and 48. Each sprocket gear assembly is of conventional construction and includes an axle, 49, 50, with a pair of laterally spaced sprocket gears carried on the opposite ends thereof. Accordingly, upon the application of a driving force to one or the other of said

axles

49 or 50 by said drive mechanism (not shown), the sprocket chains 46 and the material engaging slats 44 attached thereto, will be driven in the direction indicated by arrow 52.

Considering now specifically FIG. 2, and the heretofore described construction of the vehicle 10, a brief summary of the manner of operation of the vehicle 10 during loading will now be given. Initially, the bowl 20 will be in the raised position as shown in FIG. 1. When the operator reaches the location wherein earth removal is to take place, and upon the proper positioning of the vehicle 10 with respect thereto, the power cylinders 24 are employed to extend the actuator rods 26 which cause the bowl 20 to pivot about an axis provided by the rear wheel arrangement 34. This pivoting movement lowers the forward edge of the bowl construction 20 bringing the scraper blade 30 into contact with the soil. Thus, as the vehicle 10 is pulled forward by the tractor 12, the blade 30 will plane or cut into the soil with the severed material moving upwardly into the interior of the bowl 20. During this loading procedure, the elevator 42 is actuated to produce movement as mentioned previously which, due to the positioning of the lower end of the elevator 42 proximate the blade 30, facilitates thedisposition of earth into the bowl 20, as well as advancement of said earth toward the rear wall 40. When the bowl construction 20 is filled, the operator utilizes the power cylinders 24 to retract the actuator rods 26 raising the bowl so as to preclude spillage of the earth from the open forward end thereof. The vehicle 10 is then towed to a dumping site where the material in bowl 20 is expelled or ejected, and then graded and rolled.

The general or overall construction of the vehicle 10 described to this point, as well as its manner of operation during loading, are conventional features which may be found in the prior art structures. These features have been set forth, however, not only as background material, but to afford a more complete understanding and appreciation of the contribution to the art realized with the present invention. Primarily, the present invention relates to a novel bowl structure which facilitates the dumping operation and provides a vehicle that is of a more simplified, economical and rugged construction than those of the prior art, yet is capable of improved performance in service, as compared with said prior art vehicles. In addition, the present invention also relates to a novel dumping method that materially increases the operational efficiency of the vehicle.

More specifically, the present invention is concerned with two facets or features of the general construction of bowl 20; namely, that of the rear wall 40 and the base wall construction 38. Each of these features provides numerous advantages over the prior art when employed separately; however, their combination in a single' vehicle also affords advantages previously unattainable with the prior art structures.

Before discussing in detail the mode of operation of the aforementioned features of the present invention, it is believed advantageous to first set forth the preferred structural arrangements of each with respect to the illustrated embodiment.

Attention is first directed to the arrangement of the base wall construction 38, and more specifically FIGS. 2-4. In this regard, the overall base wall construction 38 is comprised of the previously mentioned scraper blade 30 which defines the leading edge thereof, and a pair of

panels

54 and 56 hingedly connected to each other along adjacent edges. When the base wall construction 38 is in the closed, material supporting condition, FIGS. 2 and 3, the free edge of the forwardmost panel 54 is disposed adjacent the scraper blade 30, while the free edge of the rearward panel 56 abuts the rear wall 40. The hinged connection for the adjacent edges of said panel is designated generally 58, and is disposed substantially in the middle of the floor area, thus provided by the base wall construction 38.

On opposite sides of each said

panel

54 and 56, proximate the free ends thereof, there are provided apertured brackets 60 disposed interiorly of the bowl side walls 36. Rotatably engaged with each pair of brackets 60 is an elongate rod or pin element 62 that extends laterally beyond the lower edges of the side walls 36. With reference to FIG. 1, bearing carriages 64 are journalled to each end of the respective rod elements 62 at a location exteriorly of the side walls 36. Each bearing carriage 64 includes one or more rollers 66 disposed in rolling contact with a track 68 formed on the adjacent exterior surface of the associated side wall 36. Thus, it can be seen that the

panels

54 and 56 are mounted for hinged articulated movement, with the movement of the free edges relative to side walls 36 being confined to a path defined by the respective tracks 68.

To provide for operation of the base wall construction 38 from the closed condition of FIGS. 2 and 3 to the open condition as shown in FIG. 4, a pair of drive arrangements are employed, each designated generally 70. One such arrangement 70 is utilized on each side of the vehicle. In this regard, a pair of brackets 72 are attached to panel 56, adjacent the hinge connection 58, with one being disposed on each side thereof. Pivotally connected to each said bracket 72 is a bell crank 74 which is in turn operatively connected to a power cylinder 76 mounted exteriorly of the vehicle on the associated side wall 36. The respective bell cranks 74 are journalled in apertures formed in the side walls 36, and each includes an arm element 78 disposed interiorly of the bowl and an arm element 80 disposed exteriorly of the bowl. The actuating rods 82 of the power cylinders 76 are operatively connected to the arm elements 80 of their respective bell cranks 74, such that upon extension of said rods 82 the bell cranks 74 will rotate in a clockwise direction, as indicated by arrow 84 in FIGS. 2 and 3.

The movement of the base wall construction 38 from the closed condition of FIGS. 2 and 3 to the open condition of FIG. 4 will now be considered. As the respective power cylinders 76 on each side of the vehicle are operated to rotate the bell cranks 74 in a clockwise direction, the interiorly disposed arm elements 78, as well as the hinged connection 58 move upwardly. With the actuator rods 82 completely extended, the

panels

54 and 56 will assume the position illustrated in FIG. 4, such that a pair of dumping openings are provided on opposite sides of said panels. It should be noted in this regard, that the confining of the movement of the free edges of

panels

54 and 56 to a linear path, taken in conjunction with the drive arrangements 70 which confine movement of the hinge connection 58 to a substantially vertical path, insure that the

panels

54 and 56 will assume the positioning of FIG. 4, wherein they are disposed approximately in the middle of the material supporting floor area of bowl 20.

Accordingly, with the unique and novel single-fold base wall construction 38, and the particular mode of operation afforded by the drive arrangements 70, the maximum amount of floor area is removed in defining the dumping openings. In practice, approximately percent of the effective load supporting area is removed which greatly facilitates and assures complete dumping.

Attention is now directed to a consideration of the rear wall 40, its mode of operation, and the particular operating structure of the disclosed embodiment employed in effecting said mode of operation. As will be recalled from the prior discussion, the rear wall 40 is mounted for regulated downward movement relative to the base wall 38 so as to adapt the lower portion thereof to function as a spreader or leveling blade-a feature which permits the elimination of the separate spreader attachments of the prior art constructions. In addition, the rear wall 40 is also designed for controlled retractive movement as will be detailed more completely hereinafter.

Looking to FIG. 2, the rear wall 40 is shown in the closed position with its lower edge portion abutting the adjacent free edge of the base wall construction 38 to close the rear portion of bowl 20. The rear wall 40 is mounted with respect to the rearward frame portion 32 by means of a link element 92. While one such link element is shown, any number may be employed as desired or required.

With reference to FIGS. 5 and 6, the link element 92 is pivotally connected to the rear wall 40 by a first hinge connection 94 and to the rear frame portion 32 by a second hinge connection 96 disposed below the connection 94. Accordingly, the wall 40 is free to move relative to the side walls 36 and the base wall construe tion 38 by pivoting about the connection 96 to the rear frame portion 32.

In addition, a power cylinder 100 is provided for operating the rear wall 40. The power cylinder 100 is carried by the frame 32 and has its actuating rod 102 connected to the link element 92 at a point 104 disposed below the

aforementioned connections

94 and 96. The lower portion of the link element 92 disposed adjacent the point of connection 104 is not physically attached to the rear wall 40 but in effect provides an abutment surface 106 against which said wall is engaged. Thus, upon extension of the actuating rod 102, as shown in FIG. 2, the rear wall 40 and link element 92 will pivot about the connection 96 to bring the lower portion 90 of said wall into abutting engagement with the free edge of the base wall construction 38.

When it is desired to initiate the dumping cycle for the vehicle 10, the power cylinder 100 is employed to retract the actuating rod 102. With reference to FIGS. 3 and 5, due to the weight of the earth fill bearing against the rear wall 40, said wall will remain in engagement with the abutting surface 106, causing same to pivot rearwardly about the connection 96 from the position illustrated in dotted outline to that shown in full line. When this occurs, an elongate opening will be formed between the lower portion 90 of the rear wall and the free edge of panel 56 which permits initial dumping of the earth fill, as shown in FIG. 3.

Considering now specifically FIG. 5, the full line position of the rear wall 40 as shown, corresponds to I that of FIG. 3. In this regard, it can be seen that the lower portion 90 of the rear wall 40 will move rearwardly until it abuts against a crossbrace element 110 of the rear frame portion 32. This crossbrace 1 10 in effect provides stop means which limit the retractive movement of the rear wall 40 away from the free edge of panel 56.

Looking now to FIG. 6, upon the further retraction of the actuating rod 102, the abutment surface 106 formed on the lower portion of the link 92 will move out of engagement with the rear wall 40. As retraction of the lower segment of link 92 continues,.link 92 will pivot about the point of connection 96 with frame 32, as well as the point of connection 94 with the rear wall 40, causing the rear wall 40 to pivot forwardly slightly about the point of engagement with brace 110, and to move downwardly. The downward movement afforded by this action results in a lowering of the entire rear wall 40, so as to vary the position of the lower portion 90 with respect to. the vehicle 10. Thus, it can be seen that after the rear wall 40 engages the stop means, the

' condition as shown in FIG. 5, the relative disposition of the lower edge portion 90 thereof can be adjusted anywhere between the positions shown inFIG. Sand that of FIG. 6 by operation of the power cylinder 100. Accordingly, this lower wall portion is now available for use as a spreader blade to grade the material being dumped from bowl 20 as vehicle 10 moves forward.

In FIG. 7, there is illustratedan arrangement which may be employed to provide for control of the retractive movement of wall 40, such that the size or extent of the opening thus formed may be selected as desired. It will be recalled, that with the structures of FIGS. 5 and 6 retractive movement will continue until the rear wall 40 engages the crossbrace 110. Accordingly, by the employment of insert elements 112 of various sizes which are engaged over the brace 110, the degree of retractive movement and the size of the resulting opening formed by rear wall 40 can be regulated as desired.

With the above-separate discussions of the construction of base wall 38 and the rear wall arrangement 40 in mind, and with reference to FIGS. 2-4, one mode of operation for the vehicle 10 will now be considered. However, before entering into this discussion, it should be noted that the hereinafter to be discussed mode of operation is but a preferred one, and that others may be relied upon. Accordingly, it is envisioned that either the base wall 38 or the rear wall arrangement 40 can be operated separately, as well as jointly, or the joint operation employed may vary from that discussed hereinafter, the particular sequence of operation to be used depending upon the conditions encountered in service.

Considering now primarily FIGS. 2-4, once the bowl is completely filled, as mentioned previously, the vehicle 10 is towed or pulled to a dumping area. When the vehicle 10 is positioned to the operators satisfaction, the power cylinder 100 is energized to commence retractive movement of the rear wall 40 away from the free edge of panel 56. This retractive movement, as indicated in F IG.'3, provides an initial dumping opening through which material is expelled. However, the size of this opening which may be adjusted as mentioned with regard to FIG. 7, is insufficient to achieve complete emptying of the bowl construction. The retraction of the rear wall 40 continues until the lower portion thereof abuts the crossbrace 110, or one of the adaptors 112 of FIG. 7. This movement causes the upper portion of the rear wall 40 to move forward and slightly downwardly of the load, with the illustrated wiper arms 114 scraping the interior surfaces of the bowl side walls 36 to loosen any material that may have stuck thereto.

Next, at the operators option, the rear wall 40 may be lowered so as to properly position the lower portion 90 thereof for the spreading or grading of the earth fill material to be dumped. In this regard, the relative positioning, or height, of the lower portion 90 may be adjusted as desired by controlling the extent of retraction of the actuator rod 102.

The operation of the base wall construction 38 may take place at any time, that is, either before or after actuation of the rear wall 40, and even separately of said rear wall. In this regard, the initiation of the operation of base wall construction 38 may be performed automatically or manually by use of the overall control mechanism of vehicle 10 (not shown). In either instance, the power cylinders 76 are energized to extend actuator rods 82, thus rotating the bell cranks 74 in the clockwise direction to slide the

panels

54 and 56 from the closed condition to the open condition.

Immediately upon commencement of the operation of the base wall construction 38, the operator will move the vehicle 10 forward to facilitate dumping, with the lower portion 90 of the rear wall 40 functioning as a spreader or grader attachment to level the material being dumped. The completely open condition for the base wall construction 38 is illustrated in FIG. 4, and it can be seen that a large portion of the originallyavailable floor area supporting the earth fill has now been removed.

Regarding the operation of the base wall construction, it can be seen that due to the particular manner of actuating the base wall construction and the mounting of the

panels

54 and 56 to the side walls, the folded structure thus resulting is disposed substantially in the middle of the originally available floor area with dumping openings being provided on the opposite sides thereof. Also, it should be noted that

panels

54 and 56, and the rear wall 40 during operation to the open condition, move-away from the elevator structure 42, or any surfaces against which earth fill material can be compressed, so as to preclude adhesion of this material to bowl 20 and to facilitate the expelling thereof under the influence of gravity.

In conclusion, it is seen from the above description of the invention and the enumeration of certain of the results achieved, that there is provided a novel vehicle structure of rather simple, troublefree, rugged construction. While one specific embodiment of the present invention has been described above and illustrated in the drawings, it is envisioned that those skilled in the art may make various modifications, alterations or substitutions with regard to the mode of operation and the specific elements, parts, or the like, so discussed; said changes being effected without departing from the spirit and scope of the invention, which is defined by the claims appended hereto.

What is claimed is:

1. In a vehicle for transporting earth or other material, a scraper bowl construction having an open front end, and comprising: means defining a pair of spaced side walls; a rear wall arrangement operatively positioned relative to said side walls for closing a rear end portion of the bowl; and means defining a base wall for supporting said earth and other materials, and including relatively movable structure operative from a closed condition to an open condition wherein at least one dumping opening is provided; the improvement wherein said rear wall arrangement comprises; a rear wall member mounted for vertical movement relative to said side walls and said base wall, and said rear wall member including blade means defined by the lower portion thereof and adapted for the grading and spreading of material emptied from said bowl, and operating means for effecting selective vertical movement of said rear wall member so that the operating level of said blade means may be adjusted as desired.

2. A scraper bowl construction as defined in claim 1 wherein said rear wall arrangement further includes means providing for movement of said rear wall member rearwardly away from said base wall, to provide an opening through which material may be dumped.

3. A scraper bowl construction as defined in claim 2 wherein said operating means includes means for effecting both said rearward and said vertical movement of the rear wall member.

4. A scraper bowl construction as defined in claim 2, further including control means for selectively effecting either joint or separate movement of said rear wall member and said relatively movable base wall structure.

5. A scraper bowl construction as defined in claim 4 wherein said control means includes means efi'ecting movement of said rear wall member prior to the initiation of movement of said base wall structure.

6. A scraper bowl construction as defined in claim 2, wherein said means providing for rearward movement of the rear wall member includes means mounting said rear wall member for pivotal movement relative to said base wall and said side walls.

7. A scraper bowl construction as defined in claim 2, further comprising stop means against which said rear wall member will engage to limit said rearward movement, and said operating means including; at least one power cylinder having a reciprocal rod element, and an elongate bracket member pivotally connected to said rear wall member at a first point and to said rod element at a second point disposed below said first point, said bracket member further being pivotally connected to said bowl construction at a third point intermediate said first and second points, such that upon retraction of said rod element, the wall member will pivot rearwardly about said third point until the lower portion thereof engages said stop means, with continued retractive movement of said rod element causing the entire rear wall member to move vertically such that the lower portion thereof may be employed in the grading of the material to be dumped.

8. A scraper bowl construction as defined in claim 2, further including stop means against which said rear wall will engage to define the limit of its rearward movement away from said base wall structure, said stop means being adjustable to vary the size of the opening thus produced upon said rearward movement.

9. A scraper bowl construction as defined in claim 1, wherein said relatively movable base wall structure comprises: a pair of panel members, said members being hingedly connected along adjacent edges, and having the opposed free edges thereof disposed proximate the rear wall member and the open front end portion of the bowl, respectively; means slidably connecting said panels to the side walls proximate the free edges thereof; and operating means connected to the rearwardmost panel for moving said hingedly connected panel edges upwardly with said free edges moving toward each other thereby providing a pair of dumping openings.

10. In combination, a vehicle for transporting earth or other similar material, said vehicle including a scraper bowl construction having an open front end portion facilitating the loading of material therein; said bowl construction comprising: a pair of spaced apart side walls; a base wall intermediate said side walls for supporting said material, and including means for providing at least one dumping opening for the emptying of material from said bowl construction; and a rear wall operatively positioned relative to said side walls and said base wall for closing the rear end portion of said bowl; the improvement comprising: blade means carried by the lower portion of said rear wall, and means mounting said rear wall for vertical movement relative to said side walls so as to permit the positioning of said blade means for the grading of material being dumped from said bowl.

11. The combination as defined in claim 10 wherein said means mounting the rear wall for vertical movement further include means permitting retractive movement of at least the lower portion of said rear wall relative to the base wall so as to provide a space along the rearwardmost edge of the base wall through which material may be expelled from said bowl construction.

12. The combination as defined in claim 11 wherein said bowl construction includes a rear frame portion, and said means for mounting the rear wall for vertical and retractive movement comprises: stop means against which said rear wall engages to limit said retractive movement; drive means carried by said rear frame portion; and link means pivotally connected to said rear wall, said frame and said drive means, the pivotal connection to said rear wall being at a first location with the connection to said drive means being at a second location disposed below said first location and said pivotal connection of the link means to the frame being at a third location intermediate said first and second location, such that said drive means will produce vertical movement upon operation thereof by pivoting said rear wall rearwardly about the pivotal connection of said link to the frame until said rear wall engages said stop means with further operation of said drive means causing said rear wall to move vertically downwardly.

13. The combination as defined in claim 12, wherein said stop means is adjustable to control the retractive movement of said rear wall.

14. The combination as defined in claim 10 further including means mounting said rear wall for pivotal movement about an axis disposed intermediate the upper end lower edges thereof, such that the portion of the rear wall above said axis pivots forwardly and downwardly while that portion below said axis moves rearwardly away from the base wall to provide a dumping opening immediately below material engaged against said rear wall, with said forward and downward movement of the portion of the rear wall above said axis tending to initiate dumping of material from said dumping.

15. The combination as defined in claim 14, wherein a portion of the base wall includes blade elements which facilitate initiation of the dumping operation, as well as scrape the interior surfaces of said side walls.

16. A scraper bowl construction for use with a vehicle of the general type employed in the transporting of earth or other similar materials, said bowl construction being open at the front end portion thereof to facilitate loading and comprising: a pair of spaced apart side walls; a base wall arrangement intermediate said side wall for supporting said material, said base wall arrangement including means for selectively providing a dumping opening therein adjacent the rearward portion of said bowl; and rear wall means closing the rear portion of said bowl, and including a rear wall member disposed between said side walls having a lower portion thereof positioned adjacent a rear edge of said base wall arrangement when both are in a closed condition, and means for effecting selective movement of said rear wall member rearwardly and downwardly with respect to said side walls and said base wall arrange ment to define an open condition for said rear wall means, wherein said lower portion of said rear wall is positionable at selected levels for use in the grading of material being emptied from said bowl.

- 17. In a vehicle for transporting earth or other similar material, a scraper bowl construction having an open forward end portion through which material is loaded and comprising: a pair of spaced side walls, a rear wall disposed intermediate said side walls to close the rearward end portion of said bowl; and base wall structure for supporting said material, said base wall including first and second panel members, having oppositely disposed free edges and adjacent edges, hingedly connected together, the free edge of said second panel member being disposed forwardly toward said open end portion of the bowl with the free edge of said first panel member being disposed rearwardly toward said rear wall when said base wall is in a closed condition,

, such that'said panel members provide flat surfaces for supporting material in said bowl; means slidably connecting said first and second panels to said side walls proximate the free edges thereof; and operating means for moving said panels from the closed condition to an open condition by moving each said free edge relative to said side walls and toward each other while the bingedly connected edges of said panels move upwardly, to provide dumping openings on opposite sides of said panels when in the open condition.

18. A scraper bowl construction as defined in claim 17, wherein said operating means include a pair of bell crank arrangements journalled to the respective side walls of said bowl construction, each said bell crank arrangement including a pair of arm elements, one said arm element being disposed exteriorly of the associated side wall and the other interiorly thereof, said interiorly disposed arm elements being connected to one of said panel members proximate the hingedly connected edges, and said exteriorly disposed arm elements being operatively connected to a driven reciprocal member for producing rotative movement of said bell crank, which movement effects the operation of said panel member.

19. A scraper bowl construction as defined in claim 17, wherein said means slidably connecting said panels to said side walls, includes track means carried by said side walls, an elongate rod element carried by each side panel, a pair of carriage members rotatably engaged to the opposed ends of each rod element exteriorly of said side walls, and bearing means carried by each said carriage member in rolling engagement with said track means.

20. A scraper bowl construction as defined in claim 17, further including blade means on a lower portion of said rear wall and means mounting said rear wall for retractive and vertical movement away from the rear edge of the base wall structure, such that said vertical movement will dispose said blade means for engagement with material being dumped from said bowl.

21. A scraper bowl construction for use with the vehicle of the general type employed in the transportation of earth or other similar materials, said bowl construction being open at the front end thereof to facilitate loading and comprising: a pair of spaced apart side walls; a base wall arrangement intermediate said side walls for supporting said material, said base wall including first and second panel members having adjacent edges hingedly connected together with the remote edges of said panels being slidably mounted to tracks on said side walls, and means for operating said panels from a closed, material supporting condition with said remote edges positioned toward the front and rear bowl portions, respectively, to an open condition by moving said remote edges toward each other while said adjacent hinged edges are moved upwardly, such that in the open condition, a pair of dumping openings are provided on opposite sides of said panel; and rear wall means including a rear wall member closing the rear portion of said bowl construction and having a lower portion thereof positioned adjacent the remote edge of the rearwardmost panel of said base wall when said base wall arrangement and said rear wall means are both in the closed condition, and means for effecting selective movement of said wall member rearwardly and downwardly with respect to said side walls and said base wall arrangement to define an open condition for said rear wall means, wherein said lower portion of the wall member is positionable at selected levels for use in grading of material being emptied from said bowl.

22. A method of dumping earth or other material from a scraper bowl, which bowl is of a type including a pair of spaced side walls, base wall structure comprised of a pair of panels having adjacent edges hingedly connected together and remote edges slidable longitudinally relative to said side walls, said remote edges being disposed toward the forward and rear bowl portions respectively, when in the closed condition, and a rear wall section mounted for retractive movement from a closed condition with its lower portion disposed adjacent the rearwardmost panel edge to an open condition; said method comprising the steps of: first moving said rear wall section rearwardly away from said base wall to provide a space defined by the rearward edge of the base wall and the lower portion of said rear wall, through which material may be initially emptied from said bowl; and then moving both said remote edges of the base wall panels relative to said side walls and toward each other, while simultaneously moving said hingedly connected edge portions upwardly to define a pair of base wall dumping openings through which the remaining material in said bowl construction can be emptied.

23. A method as defined in claim 22 wherein said step of moving the rear wall section rearwardly includes the step of moving said section downwardly with respect to said sidewalls to dispose the lowermost portion thereof in position for grading the material dumped from said bowl.

24. A method as defined in claim 23 wherein the mounting of said rear wall is achieved with a link arrangement pivotally connected to said rear wall and a rear frame portion of the bowl construction, thus defining a fixed and a floating pivot, and said steps of moving the rear wall section rearwardly and downwardly include the step of first pivoting said wall section and said link arrangement about the fixed pivot to cause the lower portion thereof to move away from the base wall, engaging said lower section against stop means to preclude further retractive movement and then effecting relative pivotal movement between said link arrangement and said wall member about said floating pivot to cause the entire wall member to move downwardly.

25. A method as defined in claim 24, wherein said steps of moving the wall section rearwardly and downwardly include the step of applying a retracting force to said link arrangement at a location disposed below both said fixed and said floating pivots.

Claims

5. A scraper bowl construction as defined in claim 4 wherein said control means includes means effecting movement of said rear wall member prior to the initiation of movement of said base wall structure.

16. A scraper bowl construction for use with a vehicle of the general type employed in the transporting of earth or other similar materials, said bowl construction being open at the front end portion thereof to facilitate loading and comprising: a pair of spaced apart side walls; a base wall arrangement intermediate said side wall for supporting said material, said base wall arrangement including means for selectively providing a dumping opening therein adjacent the rearward portion of said bowl; and rear wall means closing the rear portion of said bowl, And including a rear wall member disposed between said side walls having a lower portion thereof positioned adjacent a rear edge of said base wall arrangement when both are in a closed condition, and means for effecting selective movement of said rear wall member rearwardly and downwardly with respect to said side walls and said base wall arrangement to define an open condition for said rear wall means, wherein said lower portion of said rear wall is positionable at selected levels for use in the grading of material being emptied from said bowl.

17. In a vehicle for transporting earth or other similar material, a scraper bowl construction having an open forward end portion through which material is loaded and comprising: a pair of spaced side walls, a rear wall disposed intermediate said side walls to close the rearward end portion of said bowl; and base wall structure for supporting said material, said base wall including first and second panel members, having oppositely disposed free edges and adjacent edges, hingedly connected together, the free edge of said second panel member being disposed forwardly toward said open end portion of the bowl with the free edge of said first panel member being disposed rearwardly toward said rear wall when said base wall is in a closed condition, such that said panel members provide flat surfaces for supporting material in said bowl; means slidably connecting said first and second panels to said side walls proximate the free edges thereof; and operating means for moving said panels from the closed condition to an open condition by moving each said free edge relative to said side walls and toward each other while the hingedly connected edges of said panels move upwardly, to provide dumping openings on opposite sides of said panels when in the open condition.