CA1063069A - Scraper elevator drive support with alignment adjustment - Google Patents

Abstract

SCRAPER ELEVATOR DRIVE SUPPORT
WITH ALIGNMENT ADJUSTMENT
ABSTRACT OF THE DISCLOSURE

An alignment system for controlling conveyor tracking by adjusting the position of a conveyor roller relative to the conveyor to position the roller in alignment with the path of movement.

Description

-This invention relates in general to conveyor systems and, in particular, to a conveyor system used as an elevator in earth moving equipment, such as a carry-type scraper, where the elevator is used to move dirt within the scraper bowl.
More specifically this invention relates to an align-ment system for positioning a roller of a conveyor to control tracking of the conveyor as it passes over and about the support-ing rollers.
Control of the path of travel, or tracking, of a conveyor 10 is necessary to prevent the endless belt or web from tracking off the drive or idler rollers, or causing the conveyor web or belt to break. As a conveyor belt moves about the supporting roller in its endless path of movement, lateral force i8 sometimes applied to the conveyor belt causing the belt to creep or travel laterally 15 upon the rollers. This lateral movement of the belt upon the supporting rollers eventually will cause the belt to track off the rollexs or becomes sufficient to cause rupture. Such lateral force is caused by the non-parallel alignment of the supporting -- xoll~rs which may occur through the accumulation of manufacturing

2~ tolerance errors, or may be the result of damage to the supporting roller~ or conveyor frame through operations in the field. Such misalignment is especially troublesome in earth moving equipment where the conveyors carry heavy loads and are frequently subiected to heavy impact from the m~aterials being loaded into the scraper ~S bowl. Due to these unu~ual problems encountered when using a conveyor in earth moving equipment, or scrapers, the conveyor rollers are ~requently misaligned.
Scrapera generally include a box-type structure, referred to as a "bowln, open at its forward end with the bottom or floor 3p of the bowl having an ad~ustable forward cutting edge adapted to cut a predetermined amount from the upper surface of the ground.
- The bowl i~ normally open at its forward end so that the material --2 _ ~

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cut by the cutting edge as it moves through the ground will pass into the rear portion of the bowl. However, as the material is cut it accumulates adjacent to the cutting edge and does not spread uniformly throughout the bowl. Therefore, an elevator or flight-type conveyor must be carried within the bowl and positioned to therear of the cutting edge to receive the material as it is passed into the forward portion of the bowl to move it both rearwardly and upwardly for more even distribution.
These elevators generally comprise a pair of rigidly ~oined side frame members extending the full length of the elevator and carrying sprockets at the lower forward and upper rear ends which engage the chains of the flight-type conveyor. Such elevat-ors are normally provided with mounting structure which permits floating action of the elevator over the dirt or material entering the bowl so that damage cannot be done to the elevator or cutting edge when a large stone or other object is hit by the scraper. How-ever, while such structure prevents damage by permitting the elevat-or to float when a large stone is hit, these stones and the like passing into the bowl frequently damage the elevator throwing the conveyor rollers out of alignment.
Since the alignment of the elevator could not be adjusted to control tracking of the conveyor chains on the elevator idler rollers and spools, even if the equipment were initially properly aligned, in operation such misalignment resulted in equipment fa-il- -ure and costly down time of the machine in the field. The presentinVention eliminates these problems by mounting the elevator drive roller to permit alignment with the idler roller such that the conVeyor chain will txack correctly on the elevator id~ler rollers and spools. While this invention i9 believed to have general appli-cation~ to all types of conveyor sy~te~s for convenience ~f`illus-trat~on, a pxeferred embodiment will be described with reference to its use in the elevator of a scraper.

It is, therefore, an object of this invention to improve conveying systemR.
Another object of this invention is to improve con--veyor systems for earth moving equipment.
A further object of this invention is to improve alignment device~ for establishing conveyor tracking about the supporting rollers, Still another object of this invention is to provide an adjustment system for scraper elevators to maintain align-ment between the rollers and conveyor chain.
A still further object of this invention is toimprove scraper elevators by providing a drive roller mounting system which can be adjusted to maintain and establish tracking of the elevator drag chain about the drive sprockets and idler roller~.
These and other object~ are obtained in accordance with the present invention wherein there is provided a mounting system for the conveyor drive sprocXet to adjust the position of the sprocket relative to the path of movement of the drag chain to maintain and establish tracking of the drag chain about the drive sprocket and the idler rollers.
According to the above objects, from a broad aspect, the present invention provides an alignment system for estab-lishing tracking of a conveyor supported for movement in a pre-determined endless path of movement upon drive and idler rollers, The conveyor is supported in a scraper bowl of an earth moving machine. The alignment system compri~es conveyor means suppor-ted for movement in an endles3 path upon drive and idler rollers.
one of the rollers is supported at one end for pivotal movement relative to the endless path of movement of the conveyor means to piVQt the roller surface to a position parallel to the path of movement of the conveyor means at the point of contact there-~ ~ i 1~63069 with. Adjusting means is also provided in operative contactwith the other end of the roller to fix the pivotal movement thereof to establish the desired track of the conveyor in the predetermined endless path of movement. The adjusting means comprises a mounting plate supporting the roller. The mounting plate is pivotally mounted on a stationary frame by means of a pivot support having a cylindrical bar held adjacent a respec-tive end thereof between a pair of clamps secured to the sta-tionary frame. Releasable securing means extends through each of the pair of clamps and an elongate transverse slot adjacent the ends of the bar for pivoting the mounting plate to secure the roller in a desired pivotal position. The frame member is provided with elongated slots extending parallel to the long axis of the bar to adjust the position of the securing means whereby to displace the roller in a plane substantiallyparallel to that of the long axis of the bar.
Further objects of the invention, together with addi~
tional features contributing thereto and advantages accruing therefrom, will be apparent from the following description of one embodiment of the invention when read in conjunction with the accompanying drawings wherein:
Figure 1 is a side elevational view of a scraper body with portions removed utilizing the invention of this application, ~
Figure 2 is a horizontal planar view of a portion of ~ -the scraper elevator to better illustrate the adjustable drive sprocket, Figure 3 is a sectional view of the apparatus shown in Figure 2 taken along lines 3-3, Figure 4 is an exploded view of a portion of the drive sprocket pivot support to better illustrate portions thereof, - 4a -.~ 4 ~.
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Figure 5 is an enlarged vertical planar view of a portion of the end of the drive shaft shown in Figure 2 to better illus-trate a portion of the drive sprocket adjusting apparatus; and Figure 6 is an enlarged view of a portion of the pivot support shown in Figure 2.
Referring now to the drawings, there is shown in Figure 1 an embodiment of the subject invention in a suitable environ-ment such as the scraper bowl of an earth moving machine. Although this invention may be used in many conveying systems for varying applications, for convenience of illustration the preferred embodi-ment is described with reference to its use as a scraper elevator.
While the scraper does not form any part of this invention it is believed that a general description of a scraper will assist in better understainding of this invention.
A scraper 10, as illustrated in Figure 1, generally comprises a pair of vertical side walls 11 and 12 spaced o~e from the other by a bottom 15 and a rear wall or abutment 17 to define a bowl having an open front end. The scraper bowl is supported at its rear end by a pair of wheels 20, only one of which is shown, and at its front end by a draft frame 30 having a pair of rear-wardly extending legs 31 and 32 pivotally connected to the vertical side walls 11 and 12 by a transverse pivot axis 35. The scraper bowl includes a cutting edge 14 at the front end of the bottom 15 which excavates a predetermined amount of material as the scraper passes over the ground.
The amount of material removed from the ground as the scraper passes thereover is controlled by raising or lowering the front end of the scrAper and, therefore, the cutting edge 14 car-ried at the front end of the bottom 15~ This positioning is effec-ted by a pair o hydrAulic ~acks 40 interconnecting the drAft frame30 with the fxont or leading portion8 of the side walls 11 and ~2.
The ~acks 40 are expanded or contracted to determine the depth of .

cut of the cutting edge 14. The excavated material will there-after pass into the scraper bowl as the scraper is moved forwardly.
Since the excavated material has a tendency to pile up and accumulate in the forward portion of the bowl, an endless con-veyor or elevator mechanism 100 incorporating the subject of thisinvention, is carried within the bowl adjacent the front end.
During excavation, the endless belt of the elevating mechanism is powered in a counter-clockwise direction (referring to Fig.l) to assist in moving the excavated material upwardly and rearwardly into the bowl to obtain more uniform distribution. To facilitate efficient loading of the excavated material as it passes over the -cutting edge 14 into the scraper bowl, the lowermost end of the elevator is adjustably positionable relative to the cutting edge, such adjustable positioning of the lowermost end of the elevator allows the elevator to handle varying or changing conditions in the excavated material.
In order to minimize damage to the conveyor mechanism lO0 during operation of the scraper in the field, such as in the event large stones or rocks are struck by the cutting edge 14, the conveyor mechanism is supported to float within the scraper bowl.
A pair of downwardly and rearwardly extending arms lll, one of which is show~n, are pivotally connected to the side walls 11 and 12 of the scraper bowl and the conveyor frame such that upon strik- -ing a large`rock or boulder the conveyor apparatus will pivot verti-cally upward about a transverse axis. The lowermost endlof the elevator 100 i8 carried on shock mounts 13 supported by the side walls ll and 12 of the scraper bowl through appropriate brackets to allow the elevator to reely pivot upon encountering such ob~ects.
Reerring now to Fig. 2, the conveyor or elevator 100 in-cludes drive and idler sprocket assemblies 120 and 140, respective-ly, rotatably ~ournaled between two spaced parallel frame members , ,., ., , . . . . ~
. . . . . , :. ~ , 101 and 102 to define the run length of the conveyor. The two spaced parallel frame members 101 and 102 form a frame 110 which is supported at its upper end between the side walls 11 and 12 of the scraper bowl by means of the downwardly and rearwardly ex-tending arms 111 and the shock mount 13 at the lower end. A drag chain conveying system 150 extends about the drive and idler spro-cket assemblies and includes a plurality of drag bars or buckets 151 which are appropriately secured to the chains 152.
The idler sprocket assembly 140 is rotatably supported between the frame members 101 and 102 at the lowermost end of the conveyor by means of suitably sealed bearings. A pair of idler sprockets 141 are secured to an idler spool 142 to be freely rotat-able about the supporting shaft in response to movement of the drag chains 152 through the excavated material.
The drive sprocket assembly 120, including a pair of sprockets secured to a rotatable spool 122, is supported from the uppermost end of the elevator and is driven by a drive motor MOT-l operatively connected thereto which supplies the power to the drive sprocket assembly for moving the drag chain conveyor 150 in its endle~s path of movement through the excavated material. One end o~f the drivè sprocket assembly 120 is pivotally supported from frame member 101 by means of a pivot support 125. The opposite end of the drive sprocket assembly is supported by frame member 102 by means of an adjustable support plate 135 which functions to control or limit the pivotal movement of the drive sprocket assem-bly about the pivot support 125.
The drive motor MOT-l, having its output shaft opera-tively connected to one end of the drive sprocket assembly, is carried by the frame member 101 through a mounting plat~ 121 to which the motor is secured. The mounting plate 121 is pivotally mounted on frame member 101 through the pivot support 125 by a cylindrical bar 123 secured to the mounting plate 121 as by welding.

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, Each end of the cylindrical bar 123 is formed with a slot 124 (Fig. 4) for a purpose to be hereinafter described in detail.
Although for purposes of illustration a slot 124 is shown formed in bar 123, it is to be understood that various aperture configur-ations may be formed in the bar to accomplish the same purposes.
Referring more specifically to Figures 3,4, and 6, the cylindrical bar 123 is secured to the conveyor frame member 101 by means of a pair of cylindrical clamps 128, one of which is shown carried by the elevator frame. The cylindrical clamps are position-ed on the frame member 101 to engage opposite ends of the cylin-drical bar 123 for securing or fixing the cylindrical bar, and therefore the mounting plate 121, relative to the elevatox frame.
A bolt 127 having a diameter less than that of the slot or hole 124 formed in the cylindrical bar, is carried by each of the cylin-drical clamps 128 and passes through the slot 124 to secure the cylindrical bar to the elevator frame member 101.
Since the slot or hole 124 is of a diameter larger than -that of the securing bolt 127, the cylindrical bar may be pivoted relative to the cylindrical clamps 128 within the limits defined by the shank of the bolt 127 engaging the sides of the slot or hole.
In this manner the drive sprocket assembly 120 and drive motor supported from the mounting plate 121 may be pivoted relative to the conveyor frame, and then clamped in a fixed position by the tightening of the bolts 127 passing through the cylindrical clamps 128.
Frame member 101, which carries the cylindrical clamps 128 is ~ormed with elongated slots 107 extending in a direction ~ubstantially parallel to the center axis of the cylindrical bar 123. Fastening bolts 127, of each cylindrical clamp 128, pass through these slots 107 to allow the drive sproc~et assembly to be moved or ad~usted in a plane substantially normal to that of the pivotal movement.

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Since in field operation, and on occasion upon initial installation of the elevator 100 within the scraper bowl, it has been found that the drag chains 152 do not track properly about the drive and idler sprocket assemblies, the chains 152 frequently track from the respective sprockets or break. Therefore, by re-positioning or realigning of either the sprocket assemblies 120 or 140 relative to the other, the drag chaihs will track properly about the respective sprockets. The repositioning or realignment of the sprocket assemblies is accomplished by pivotal movement of the drive sprocket assembly 120.
Control of the pivotal movement of the drive sprocket assembly 120 about the pivotal support 125 is effected at the end opposite thereto by means of the adjustable support plate 135 which rotatably supports the drive sprocket assembly through appropriate bearings and is best illustrated in Fig. 5. The adjustable support plate 135 is formed with a series of elongated slots 136 which e~tend in a direction substantially parallel to the run of the con-veyor. A series of bolts 137 extend through the slots 136 and are fastened to an extending portion 104 of the elevator frame member 102. The extending portion 104 is also formed with a series of slot8 136 formed in the ad~ustable support plate 135 to provide for ad~ustment or movement of the drive sprocket assembly in the same manner as the slots 107 formed in the elevator frame me~ber 101 .
In order to establish proper tracking of the drag chains 152 about the drive and idler sprocket assemblies, the position of ad~ustable support plate 135 and, therefore, pivotal movement of the drive sprocket assembly about the pivot support 125 is effect-ted by a ~ack screw 138 carried by the extending portion 104 of the elevator frame member 102. The ~ack screw 133 is carried by a threaded bracket 139 and positioned to engage the lowermost portion of the ad~ustable support plate 135. In this manner the ~ack screw 138 may be threaded through the bracket 139 to engage the adjustable -support plate 135 for pivoting the drlve sprocket assembly relative to the frame 110 to insure proper tracking of the drag chain about the drive and idler sprockets. To effect alignment bolts 137 are loosened and the jack screw turned to position the drive sprocket assembly 120 in proper alignment. After the jack screw 138 has ~een turned to position the adjustable support plate 135 in the proper orientation for establishing tracking of the drag chains 152, the bolts 137 are tightened. Proper positioning of the jack screw 138 is maintained by a lock nut 134. The lock nut 134 thread-ingly engages the jack screw 138 and is tightened against the threa-ded bracket 139 to prevent the jack screw 138 from turning during operation of the elevator. ~-While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it ls intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this inventio~, but that the invention will include all embodiments falling within the scope of the appended claims.

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Claims (4)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:-

1. An alignment system for establishing tracking of a conveyor supported for movement in a predetermined endless path of movement upon drive and idler rollers, said conveyor being supported in a scraper bowl of an earth moving machine, said alignment system comprising conveyor means supported for move-ment in an endless path upon drive and idler rollers, one of said rollers being supported at one end for pivotal movement relative to the endless path of movement of said conveyor means to pivot the roller surface to a position parallel to the path of movement of the conveyor means at the point of contact there-with, and adjusting means in operative contact with the other end of said roller to fix the pivotal movement thereof to estab-lish the desired track of the conveyor in the predetermined end-less path of movement, said adjusting means comprising a mounting plate supporting said roller, said mounting plate being pivot-ally mounted on a stationary frame by means of a pivot support having a cylindrical bar held adjacent a respective end thereof between a pair of clamps secured to said stationary frame;
releasable securing means extending through each said pair of clamps, the stationary frame and an elongate transverse slot adjacent said ends of said bar for pivoting said mounting plate to secure said roller in a desired pivotal position, said frame member having elongated slots extending parallel to the long axis of said bar to adjust the position of said securing means where-by to displace said roller in a plane substantially parallel to that of the long axis of said bar.

2. The apparatus of claim 1 wherein said roller supported at one end for pivotal movement is supported at said end for movement in a plane transverse to the plane of pivotal movement.

3. The apparatus of claim 1 wherein said aperture formed in said cylindrical bar defines the limits of relative movement between said cylinder and said cylindrical clamps.

4. The apparatus of claim 2 wherein control of the pivotal movement about said bar is effected at said one end by means of an adjustable support plate having elongated slots permitting adjustment thereof in a vertical and horizontal direction rela-tive to a stationary mounting plate.