Figure 9-9.—Up-and-down pitching of a loader on irregularterrain.sufficient working space for the loader. This stepprevents up-and-down pitching of the loader (fig. 9-9)and results in a smoother digging operation.Track and wheel spinning should be avoided,because loader tires are expensive and excessivespinning of the tires while loading causes prematurewear and tear. Additionally, it converts a smoothworking area into ruts that pitch and tilt the loader. Asmooth working area is safer and more comfortable. Italso puts less wear and tear on the machine and yourself;therefore, production is increased.Cross ditches, ridges, rocks, or logs slowly and, ifpossible, at an angle. This procedure slows the fall,lessens the danger of upsetting the loader, and reducesthe jolt of the fall that can harm both the operator andthe loader.A uniform system of hand signals must be used inall front-end loader operations. While the authority forgiving signals must be assigned to only one person undernormal working conditions, the responsibility for givingan emergency stop signal belongs to anyone in thevicinity who believes such a signal is necessary. Theperson giving the signals must be clearly visible to theoperator at all times. Hand signals used in front-endloader operations are shown in appendix IV.NOTE: You must recognize and understand thesesignals when operating equipment. Additionally, youmust also be able to give them when called on to act asa signalman during any equipment operation.Automatic Bucket LevelerMost 515 B series dresser rubber-tired front-endloaders used in the NCF have an automatic bucketFigure 9-10.—Automatic bucket leveler.leveler located on the underside of the bucket cylinder(fig. 9-10).The automatic bucket leveler is preset to stop thebucket in a horizontal or digging position. A trip bar (1)is attached to and moves with the cylinder rod. Theproximity switch (2) creates a magnetic field circuit thatis completed by the proximity of the trip bar within themagnetic field. Once the bucket is dumped, place thebucket lever in the bucket “rollback” position. When thebucket reaches its preset position, the trip bar moves outof the magnetic field circuit created by the proximityswitch and automatically stops. Then the bucket controllever returns to the “hold” position.NOTE: Refer to the manufacturer operator’smanual when the automatic bucket leveler needsadjustment.Position IndicatorThe general-purpose bucket shown in figure 9-6 isnormally used as a skid shovel. The multipurpose bucketshown in figure 9-7 serves as a skid shovel, but can alsobe used as a bulldozer, scraper, and clamshell.Most front-end loaders are equipped with six bucketcontrol lever positions, such as raise, hold, lower, floatdump, and rollback. Dump and rollback can be used9-6
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