Method and apparatus for aggregate-dispensing hopper conveyance and tracking

Abstract

A dual-hopper aggregate spreader for spreading a layer of loose aggregate onto a road surface usually consists of a receiving hopper for the loose aggregate, and two (dual) second dispensing hoppers. In the preferred embodiment the conveyance of the dispensing hoppers is facilitated, in conjunction with other mechanical apparatuses, by a minimum of two conveyance glides, instead of rollers, gears, sprockets, etc., attached to a stationary frame that carries and aids in the conveyance of the dual dispensing hoppers, a minimum of two conveyance glides attached to the dual dispensing hoppers that then come into direct contact with the aforementioned frame glides, and, lastly, a minimum of two —one per side—tracking glides attached to the dual dispensing hopper's sides immediately adjacent and perpendicular to the conveyance glides.

Description

PATENT CROSS-REFERENCES

U.S. Patent Documents

6,161,986 December, 2000 Smith et al.

6,805,516 B2 October, 2004 Barnat et al.

BACKGROUND

1. The Field of the Invention

This invention relates to road construction and, more particularly, to novel systems and methods for facilitating the spreading of loose aggregate onto a road surface.

2. The Background Art

Since the cost of roadways is substantial, it is desirable to lengthen the useful life of a road as much as possible. To make roads last longer, they are sometimes treated for preventive maintenance. Preventive maintenance of a road surface can reduce the likelihood of the road surface becoming cracked or chipped, having potholes appear, and developing other similar problems that often occur with roads.

There are several ways that road surfaces can be treated to help lengthen the life of the roadway. Chip seals, also known as oil and screenings, aggregate seal coats, and armor coats, are surface treatments which are placed on an existing asphalt pavement. Applying a chip seal to a road is one form of preventive maintenance that can be used to increase the life of a roadway. Generally, the chip seals do not add structural strength to the roadway, but they do produce an ideal all-weather surface, renew weathered pavement, improve skid resistance, and seal the old pavement.

Chip seals are applied to a roadway by first spraying the pavement with a binder, often an asphalt emulsion, from an oil distributor truck. This binder is a tacky coating placed onto the road surface that acts to bind gravel, to be applied soon thereafter, to the road surface. After the binder is applied to the road surface, a uniform application of cover aggregate (similar to and including fine gravel) is applied, usually by a self-propelled chip spreader. For example, chip seals usually employ ¼ to ½ inch (0.64 to 1.3 cm) aggregate. As the aggregate (i.e., gravel) contacts the sticky binder coat, it tends to stick to the road surface. The aggregate is usually rolled as soon as possible to ensure the adhesion of the aggregate to the binder and pavement surface.

There are many different designs and types of machines employed to spread the aforementioned aggregate as evenly as possible. Most, if not all of these machines are complex, requiring precision movements to ensure the proper amount of aggregate is dispensed; for example, as described and patented in U.S. Pat. No. 6,161,986. Many of these machines employ a hopper system, wherein the aggregate to be placed on the road surface is first poured into a hopper or bin where it is then evenly dispensed.

Some chip spreader designs employ dual, horizontally translatable aggregate-dispensing hopper systems where in two hoppers are loaded with aggregate and then the hoppers are moved into various positions to dispense the aggregate, as diagrammed, but not patented, in U.S. Pat. No. 6,805,516 B2. Tremendous loads are oftentimes carried in the dispensing hoppers while the aggregate is temporarily contained therein. Such loads cause large stresses to many of the assemblies designed to move or convey the hoppers into place so that the optimal amounts of aggregate can be dispensed. In the past, most of these dual-hopper conveying systems employed rollers to bear the weight of the hopper. Due to the localization of stresses to the roller/hopper contact surfaces, expensive materials were required in the manufacture of the roller shafts and bearing and tracking systems components. See detailed parts lists and views of the various caster/shaft configurations employed industry wide at www.geffs.com, www.ennyre.com and www.bearcatmfg.com.

BRIEF SUMMARY AND OBJECTS OF THE INVENTION

In view of the foregoing, it is a primary object of the present invention to provide an aggregate spreader dual hopper conveyance method and apparatus to lessen the load per square unit localization of stresses due to the use of rollers and/or gears. In employing the proposed invention, the conveyance of aggregate-dispensing dual hoppers on chip spreaders will cost less due to less costly materials being used to manufacture the conveyance assemblies. The reduction in cost can be past along to the purchaser of these machines.

Another object of the present invention is to eliminate rollers and/or gears from being employed to convey aggregate-dispensing hoppers, and thus eliminate the common occurrence of one roller or gear shaft breaking and/or malfunctioning and thus rendering an entire machine temporarily inoperable.

In the preferred embodiment, the conveyance method and apparatus include a minimum of two glides attached to the stationary frame that carries the hoppers, a minimum of two glides attached to the hoppers that then come into direct contact with the aforementioned frame glides, and, lastly, a minimum of two tracking glides attached perpendicularly to the hopper sides immediately adjacent to the aforementioned glides.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects and features of the present invention will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only typical embodiments of the invention and are, therefore, not to be considered limiting of its scope, the invention will be described with additional specificity and detail through use of the accompanying drawings in which:

FIG. 1 is a perspective view of one possible embodiment of a dual aggregate spreader hopper system shown with the aggregate-dispensing hoppers supported by a stationary frame in a minimum width configuration;

FIG. 2 is a perspective view of one possible embodiment of a dual aggregate spreader hopper system shown with the aggregate-dispensing hoppers supported by a stationary frame in a maximum width configuration.;

FIG. 3 is a left side view of the aforementioned frame/hoppers system illustrating the hoppers being supported by the frame;

FIG. 4 is a enlarged detail of FIG. 3 further showing the glides which act as bearing surfaces attached to the frame, the glides which act as bearing surfaces attached to the movable hopper, and the glides which act as tracking guides attached to the hopper sides;

FIG. 5 illustrates that the glides are attached to the entire length of the frame and moveable hoppers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

It will be readily understood that the components of the present invention, as generally described and illustrated in the Figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the system and method of the present invention, as represented in FIGS. 1 through 5, is not intended to limit the scope of the invention, as claimed, but it is merely representative of the presently preferred embodiments of the invention.

The presently preferred embodiments of the invention will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout.

For the purposes of this invention, a “glide” is defined as an apparatus consisting of a load bearing surface that comes in contact with another surface to provide limited part travel for one or both of the parts attached to the glide apparatus.

As shown in FIG. 1, chip spreader aggregate-dispensing hoppers (2) may be configured as a dual hopper system suspended by a frame (1). If more than one hopper is employed, the hoppers must be moved to various positions as shown in FIG. 2.

FIG. 3 Illustrates a side view of the frame (1) suspending the hoppers (2). FIG. 4 shows a detail of the contacting surfaces of the frame and hopper(s) which are often designed with gears or casters. As can be visually discerned from FIG. 4, this invention eliminates the aforementioned gears or casters, and substitutes glides as the contacting surfaces. The hopper (2) now makes contact with the frame (1) by a glide (3) attached to the hopper and a glide (4) attached to the frame. A third and fourth glide (5) act as tracking guides to keep the hopper on a demarcated path.

The advantage of such an invention is that instead of the full load of the hopper being distributed to the contacting surfaces of the relatively small tangents of the gears or wheels, and thus to the relatively small shafts that support the gears/casters, the load is evenly distributed to the entire contacting surfaces of the glides. This can be the difference of a load contacting surface area of approximately one square inch supporting over 10,000 pounds, verses, in the case of this invention, a load contacting surface supporting a mere 40 pounds per square inch at maximum. As FIG A-A illustrates, the glides extend the full lengths of the possible frame/hopper contact surfaces. Thus, as shown in FIG. 2 as a possible maximum width expansion scenario of the hoppers, the hoppers would contact from 100 percent to a minimum 50 percent of the glides' contact surfaces. This invention would lend greater stability, utilizing less moving parts and materials than any gear or caster conveyance system.

The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

1. A method and apparatus to aid in the conveyance and keep a demarcated path of an asphalt resurfacing chip spreader aggregate-dispensing hopper(s) comprising: upper glides, lower glides, and tracking glides.