Patent Publication Number: US-4255885-A

Title: Apparatus for controlling the position of the pivoting floor and strikeoff blade of an earthmoving scraper

Description:
TECHNICAL FIELD 
     The present invention relates to earthmoving scrapers and in particular to means for selectively controlling the position of the pivoting floor and strikeoff blade thereof. 
     BACKGROUND ART 
     One type of present earthmoving scraper includes a bowl assembly with a pivotable floor which is in the closed, substantially horizontal position during the earth-gathering mode and can be pivoted rearwardly to an almost vertical position for the fully opened, dirt dumping and spreading mode. Depending on the type of earth being spread, that is to say, for example, whether it has a particular clay or sand or rock content, and depending upon the desired thickness of the earth layer to be spread, it is advantageous to be able to open the pivoting floor a predetermined amount. Thus, the operator is able to control the rate of flow of earth from the bowl and also to simultaneously set the strikeoff blade of the scraper which is attached to the leading edge of the pivoting floor at a desired level to accomplish the appropriate level of spreading. 
     Heretofore, the operator of the earthmoving scraper, being unable to see the position of the strikeoff blade, had to guess as to the position thereof. Consequently, the operator did not know the exact level of the earth being spread until he was into the spreading operation and could view the level of earth coming out of the scraper. 
     DISCLOSURE OF THE INVENTION 
     The present invention is directed to overcoming one or more of the problems as set forth above. In one aspect of the invention, an apparatus is provided for selectively controlling the position of a member relative to a frame. The apparatus includes a switch for controlling the position of the member and first securing means for securing the switch to either one of said members or said frame. Further, actuation means are provided for actuating said switch and second securing means are provided for selectively securing said actuation means to the other of said member or said frame in a plurality of positions. The second securing means includes a bracket secured to the other of said member or said frame, which bracket defines a first leg and a second leg. The second securing means also includes an adjuster plate on which said actuation means is mounted and mounting means for mounting said plate to one of said legs of said bracket in one or more positions. 
     In another aspect of the invention, the adjuster plate includes first, second and third apertures and each of said legs includes first and second apertures. Groupings of two of said apertures of said plate are selectively alignable with said apertures of each of said legs to selectively positioning said plate relative to said bracket. Further, means are provided for selectively securing the plate to the bracket in one of the above aligned positions. 
     In yet another aspect of the invention, the first, second and third apertures of said adjuster plate form the corners of a triangle. The first and second apertures of said plate are selectively alignable with the first and second apertures of each of said legs of said bracket and said second and third apertures of said plate are selectively alignable with the first and second apertures of each of said legs of said bracket, with the plate rotated substantially 180°. 
     In yet another aspect of the invention the frame is of a type used on an earthmoving scraper and the member includes a member of the bowl assembly which has a pivotable floor and strikeoff blade. Thus, the invention allows for the selective positioning of the pivoting floor of the bowl and the strikeoff blade to determine the rate of discharge of the earth from the bowl of the scraper and also the height of the strikeoff blade above the ground, thereby determining the depth of the material being spread. 
     Therefore, the present invention allows the operator of the earthmoving scraper to preposition the actuating means. Once the actuation means is positioned, said actuating means will automatically actuate the switch to deactivate the hydraulic circuit controlling the rotation of the floor and thus the opening of the bowl and the level of the strikeoff blade. Such actuation occurs automatically without the inspection by the operator, and thus there is no guesswork involved in setting the level of the strikeoff blade and the rate of discharge of material from the bowl assembly. Once the material is discharged from the bowl, the switch can be overriden to return the pivoting floor to the closed position preparatory to again filling the bowl with earth, or the floor can be opened somewhat more to a maximum open position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view, partially cut away and partially sectioned, of an earthmoving scraper incorporating the present invention; 
     FIG. 2 is an enlarged portion, partially cut away of the scraper in FIG. 1 which includes the embodiment of the present invention; 
     FIG. 3 is a side elevational view of the adjuster plate of the invention; 
     FIG. 3A is an end elevational view, looking in the direction of the arrows on line 3A--3A in FIG. 2; 
     FIGS. 4, 5 and 6 depict the mounting bracket and adjuster plate of the invention with the plate positioned selectively with respect to the bracket to effect selective positioning of the pivoting floor and strikeoff blade of the bowl assembly of the scraper. 
    
    
     BASIC MODE OF CARRYING OUT THE INVENTION 
     With reference to the drawings, and in particular to FIG. 1, an earthmoving scraper is depicted and generally noted by the numeral 10. Scraper 10 includes a tractor 12 having a motor means 13 for driving front wheels 15. Tractor 12 is pivotally connected to and pulls a scraper assembly 14. Scraper assembly 14 includes a bowl assembly 16, a laterally extending earth cutting edge 18 and an elevator mechanism 20 for delivering the earth cut by the cutting edge 18 into the bowl assembly 16. Scraper assembly 14 may also include a second motor means 21 which drives rear wheels 22. 
     Bowl assembly 16 includes an arcuately shaped rear wall 24 and a pivoting floor 26 pivotal at pivot point 28. A strikeoff blade 27 affixed to floor 26 determines the height of the material discharged from bowl assembly 16. Rotating floor 26 has a fully closed, substantially horizontal position as indicated in FIG. 1 and a fully open, substantially vertical position as indicated by the phantom line and by the numeral 26&#39; in FIG. 1. A carriage assembly 30, which is connected to the rotating floor 26 by a connecting link 32, is slidably mounted beneath the second motor means 21 and actuable by hydraulic cylinder 34 for pivoting the rotating floor between the two positions as indicated in FIG. 1. A more detailed discussion of the carriage assembly can be found in U.S. Pat. No. 4,133,122, issued on Jan. 9, 1979 to William T. Girard et al. 
     Viewing FIG. 2, a magnetic proximity switch 36 is mounted to the frame 38 of the scraper assembly 14 by an adjustable bracket 40. Adjustable bracket 40 includes an upper member 42 and a lower member 44 which can be adjusted vertically by bolts 45 with respect to the member 42 to set the vertical position of magnetic proximity switch 36. Switch 36 provides a signal through conduit 46 to deactivate the hydraulic circuit which operates the hydraulic cylinder 34, as will be discussed more fully hereinbelow. 
     Secured to the rear, trailing upstanding portion 48 of carriage asembly 30 is a bracket 50 which has a first leg 52 and a second leg 54. As can be seen in FIG. 2, first leg 52 is secured to portion 48. First leg 52 includes first and second apertures 56 and 58, respectively (FIG. 6), and second leg 54 includes first and second apertures 60 and 62, respectively (FIG. 4). In a preferred embodiment bracket 50 can be V-shaped to allow access to cylinder 34. It is to be understood, however, that other configurations (not shown) of bracket 50 can allow access to cylinder 34. 
     The present invention further includes a triangularly shaped adjuster plate 64 to which is mounted an actuation means or magnet 66 for actuating the magnetic proximity switch 36. As can be seen in FIG. 3, adjustor plate 64 includes first, second and third apertures 68, 70 and 72, which are positioned in respective corners thereof. The magnet 66 is mounted on guide 67 of adjuster plate 64 adjacent aperture 68. It is to be understood that plate 64 can be selectively positioned and secured to bracket 50 by aligning the various apertures thereof and positioning bolts 74 therethrough (FIG. 3A). It is to be understood that in the position shown in FIG. 2, apertures 68 and 70 can be aligned with apertures 56 and 58 to position magnet 66 in a first of four positions. Also, plate 64 can be rotated 180° so that apertures 72 and 70 are aligned with apertures 56 and 58 (FIG. 4), to provide a second position of magnet 66 with respect to bracket 50. Still further, apertures 72 and 70 can be rotated 180° and aligned with apertures 60 and 62 of bracket 50 to provide a third position of magnet 66 as depicted in FIG. 5. Finally, apertures 68 and 70 of bracket 64 can be rotated 180° and aligned with apertures 60 and 62 of bracket 50 to dispose magnet 66 in a fourth position on bracket 50. With magnet 66 in the fourth position, the carriage 30 is most rearwardly extended to position 30&#34;, as shown in phantom in FIG. 2. 
     INDUSTRIAL APPLICABILITY 
     The operation of the present invention is as follows. For a given type of work to be performed and earth to be handled, the adjuster plate 64 can be manually positioned with respect to V-shaped bracket 50 in one of the positions shown in FIGS. 2, 4, 5 and 6 to preselect an open position for rotating floor 26 and strikeoff blade 26. As the bowl assembly 16 is being filled with earth collected by cutting edge 18 and elevator 20, the carriage is disposed in position 30&#39;, as indicated by phantom lines (FIG. 2) so that floor 26 is closed (FIG. 1). Once the bowl assembly 16 is filled and the scraper 10 is positioned preparatory to discharging the earth in the bowl assembly 16, the operator actuates an appropriate lever, causing hydraulic cylinder 34 to push carriage assembly 30 to a position where the magnet 66 actuates magnet proximity switch 36 to deactivate the hydraulic circuit which controls hydraulic jack 34. When this occurs, the rotating floor 26 and strikeoff blade 27 are appropriately positioned for the desired rate of discharge of earth from the bowl assembly 16 and the desired height of strikeoff blade 27. 
     It is to be understood that bracket 50 allows convenient maintenance access to hydraulic cylinder 34 between legs 52 and 54. 
     Other aspects, objects and advantages of this invention can be obtained from a study of the drawings, the disclosure and the appended claims.