Debris/load leveling system

A mechanized broom-type sweeper truck that includes a pavement engaging brush or broom and an elevator for transported debris to the inlet or entry opening of a debris container includes a slinging roller in the debris container mounted at or subjacent the inlet opening. The slinging roller is journalled in bearings and driven by a motor at a selected rotary speed. Surface features are provided on the roller to engage with and contact any debris coming into contact with the roller to fling, sling, throw debris away from the inlet opening.

BACKGROUND OF THE INVENTION

The present invention relates to mechanized sweeper trucks that utilize a primary broom to sweep debris from roadways and, more particularly, to method and apparatus for “leveling” the debris load within the debris container of such vehicles.

Mechanical broom sweepers are designed to pick-up debris not normally accepted by conventional regenerative or vacuum-type sweepers; this debris typically including asphalt nodules of varying size consequent to asphalt milling operations, rocks, stones, construction debris, broken masonry, and the like. In a typical design, as shown in schematic fashion inFIG. 1, a primary or main broom is rotated against the road surface to brush debris in the forward direction onto a mechanical elevator. The elevator typically includes a set of parallel flights that push the debris along an inclined floor pan to carry the debris upwardly for deposit through an entry opening of a debris collection bin or hopper. Because the density of the collected debris is relatively high, the debris drops from its point of entry and collects directly beneath its point of entry. As the debris pile accumulates and increases in elevation, the collected debris at the top of the pile tends to clog or block the entry opening, even though other parts of the collection hopper are comparatively unfilled.

In general, the problem cannot be solved by merely increasing or stepping up the operating speed of the elevator to more energetically throw the debris into the debris collection hopper. The sweeping vehicle and its main broom are best operated in speed ranges that assure the efficient sweeping of debris from the roadway and the efficient projecting of that swept debris into or onto the moving elevator. Thus, for any broom speed, the elevator speed is best maintained in a speed range that prevents a situation in which the elevator flights ‘overrun’ the brush function.

Vehicle operators have addressed this problem by abruptly applying the vehicle brakes to cause the debris pile to slump forwardly against the front wall of the debris container away from the entry opening on the rear wall of the debris collection hopper. This solution, while temporarily effective, tends to cause premature wear of the vehicle brakes and tires.

SUMMARY OF THE INVENTION

A broom-type mechanized sweeper of the type having a broom and a mechanized elevator for transferring debris to the entry opening of a debris hopper is provided with a slinger element that slings, flings, throws, or projects debris coming into contact with the slinger element therefrom. In a preferred form, the slinger element is formed as a cylindrical roller mounted for rotation about an axis and rotated by a motor. Surface features associated with the roller, such as paddles, arms, blades, a weld-bead formation(s), grooves, or a combination thereof, function to contact and engage debris falling into contact with the roller to impart sufficient kinetic energy thereto that the debris is thrown away from the roller.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 2illustrates, in side view, andFIG. 3illustrates, in rear perspective view, a portion of a mechanized broom sweeper10of the type sold by Schwarze Industries, Inc. of Huntsville Ala. under the M5000 or M6000 designations. As shown, the sweeper10includes a commercial truck chassis12(only part of which is illustrated) which carries a debris collection hopper14. As best shown inFIG. 3, the collection hopper14includes a laterally aligned entry slot16through which debris is delivered by the elevator18(FIG. 2, dotted-line illustration).

As shown inFIGS. 4A and 4B, the elevator18includes a pair of spaced apart shafts20that each carry respective spaced apart sprockets22and24. A first carrier chain26is entrained about the sprockets22of the shafts20and a second carrier chain28is entrained about the sprockets24. Debris carrying blades or flights30are supported between chains26and28function to push or carry debris along a transfer plate or floor pan32upwardly and into the entry slot16of the debris collection hopper14. The elevator18is typically powered by a hydraulic motor (not shown).

As discussed above in relationship toFIG. 1, the debris being pushed through the entry slot16of the debris collection hopper14immediately falls therebelow to form a debris pile immediately thereunder. With time, the uppermost extent of the debris pile is located immediately below the entry inlet16and hinders the continued efficient operation of the elevator18.

As shown in schematic form inFIG. 5, a “slinger’ element50is provided to sling, throw, or fling debris from or in the general vicinity of the point or area of entry in the forward direction. The slinger element50is mounted for rotation in the direction shown about an axis of rotation Axand, in the schematic representation ofFIG. 5, includes surface features in the form of four outwardly extending blades, paddles, or projections52. As shown inFIG. 6, a slinger element50is located subjacent the entry slot16and has been provided with shorter arm-like ‘stub’ projections52than those shown inFIG. 5. The projections52shown inFIGS. 5 and 6are illustrative only, since in practice, much shorter projections52are utilized. As represented inFIG. 5, the slinger element50is rotated as some speed, usually in the range of a few hundred rpm by a suitable motor (i.e., hydraulic). As debris is pushed through the entry slot16by the various flights30of the elevator18, the larger pieces drop immediately toward and/or onto the slinger element50where one or the other of the projections52contacts the debris to launch or throw the so-contacted debris forwardly to the side of the debris collection hopper14opposite the entry slot16. As a consequence, the debris will land upon and contribute to the formation of a debris pile on the side opposite the entry slot16or impact the forward wall of the debris collection hopper14and fall onto the debris pile. The amount of kinetic energy imparted to the debris should be at least sufficient to successfully transfer substantially all or almost all of the heaviest and largest pieces of debris away from the slinger element50to the side of the debris collection hopper14opposite thereof.

FIG. 7illustrates a preferred embodiment of a slinger element50. As shown the slinger element50is formed as a cylindrical roll having a side-to-side dimension of about 60 inches (1.5 meters) sufficient to accommodate the width of the entry slot16and a diameter of about 6 inches, although smaller diameter (i.e., 3-4 inch) and larger diameter (i.e., 7-9 inch) rolls are suitable depending upon the application. The slinger element50includes a mounting shaft54and is carried, at its far end, in a bearing56, that, in turn, is carried on a mounting bracket58. In a similar manner the near-end of the slinger element50is journalled in another bearing60which, in turn, is carried on a mounting bracket62to support the slinger element50.

A drive motor64, such as a fixed-speed or variable-speed hydraulic motor, is connected to the shaft54to drive the slinger element50at a sufficient speed for the average size of the debris particles, their density, and the distance that the debris particles are thrown. In general, a rotary speed in the range of 100 to 400 rpm is considered adequate. A shown inFIG. 7, speed control can be in the form of an operator-manipulated controller66and a control unit68that controls the motor64in an open loop manner or which, optionally, receives feedback information from a rotational speed sensor70to maintain rotary speed as the quantity of debris changes. While a hydraulic drive motor is preferred, other slinger propulsion devices can be used, including pneumatic motors, electric motors, or equivalents thereof.

In contrast to the paddle like arm or projections ofFIGS. 4 and 4A, the slinger element50ofFIG. 7has spirally aligned surface features72that function to engage the debris and sling, fling, or project the debris away from the entry slot16. As shown in the detail ofFIG. 8, the surface features72are formed by depositing at least one weld bead on the surface of the slinger element50that, in the case of the embodiment ofFIG. 7, follows a spiral path or pattern on the surface of the roll. As shown, a plurality of such spiral-path surface features72can be used to create the pattern shown. The weld-bead surface feature can be formed by an automatic or pre-programmed welding machine that applies the weld bead as the roll50is rotated along its axis Ax. While the spiral-pattern ofFIG. 7is preferred, other patterns are not excluded from the present invention and can include, for example, linear weld beads formed parallel to the axis of rotation Axof the slinger element50. In the preferred embodiment, the weld beam surface feature72has an elevation or height from its base to the outermost point of about 0.375 inch, although a smaller or larger-dimension weld bead is suitable depending upon the particular application.

In the embodiments ofFIGS. 4,5, and7, the surfaces features that impart kinetic energy to the debris extend outward of the diameter surface of the slinger element50. As can be appreciated, the notion of surface features can include features that are less than the outside diameter of the slinger element. For example and as shown inFIG. 9, a surface feature can include a groove or slot74that can extend laterally across the slinger element50or extend in the spiral pattern discussed above; if desired, the outwardly extending surface feature72can also be provided in combination with groove or slot74. In addition, the slinger element50can take the form of a non-cylindrical structure, such as the cruciform type slinger76shown inFIG. 10.

Regardless of the form the slinger element takes or the nature of the surface features, during normal operation of the slinger element, debris falling from the inlet entry16toward or to some part of the surface of the slinger element has a high probability of receiving sufficient kinetic energy to sling, fling, throw, or launch the debris to the side of the debris collection hopper opposite from the inlet entry opening to cause the debris pile to form away from the inlet entry opening.

As will be apparent to those skilled in the art, various changes and modifications may be made to the illustrated embodiment of the present invention without departing from the spirit and scope of the invention as determined in the appended claims and their legal equivalent.