HIGH TEMPERATURE CONVEYOR BELT

Abstract

A conveyor belt configured for a direction of travel, the conveyor belt including a plurality of connecting rods; and a spiral overlay; wherein each of the connecting rods has a flattened oblong cross section. In addition, a method a manufacturing a connector rod for a conveyor, belt includes providing a connector rod having a circular cross section; rolling the connector rod along a longitudinal axis thereof, and thereby producing a flattened oblong cross section.

Claims

1. A conveyor belt configured for a direction of travel, the conveyor belt comprising: a plurality of connecting rods; and a spiral overlay; wherein each of said connecting rods has a flattened oblong cross section.

2. The conveyor belt according to claim 1, wherein the plurality of connecting rods are formed from a metal material and have an elongated material grain in a direction perpendicular to the direction of travel of the conveyor belt.

3. In a conveyor belt comprising a plurality of connecting rods and a product support surface overlay, the improvement comprising: said plurality of connecting rods having a flattened oblong cross-sectional shape.

4. The improvement of claim 3, wherein the plurality of connecting rods are formed from a metal material and a grain of the metal material is elongated in a direction of a longitudinal axis of the connecting rod.

5. A method a manufacturing a connector rod for a conveyor belt comprising: providing a connector rod having a circular cross section; rolling the connector rod along a longitudinal axis thereof and thereby producing a flattened oblong cross section.

Description

DETAILED DESCRIPTION

[0025] To meaningfully improve camber resistance, the strength to weight ratio of the belt must be increased. A solution like double balanced belting or increasing the number of loops per foot of width in balanced belting, as done in the past, usually only gives a small increase in the strength to weight ratio because belt weight is a major factor in belt tension. Belt tension is a measure of the total load, (belt weight plus product weight) dragging across the product support surfaces. A 25% increase in belt strength and construction cost that also results in a 22% increase in belt weight only gives a minor increase in the strength to weight ratio.

[0026] The disclosure herein provides an improved cross rod (connecting rod) that allows for an improved conveyor belt, and in particular, at knuckleback belt. Referring to FIGS. 6A and 6B, in an exemplary embodiment of the disclosure, an 8 gauge circular rod (shown on the right) is roll formed into a flattened oblong shape rod 10 (shown on the left). The grains of the material are rolled along the length of the rod and become elongated in a direction along the length of the rod, i.e., perpendicular to the shear load caused by the spirals in the spiral overlay engaging the rod in tension. The cross-sectional long edges of the rods are parallel to the direction of belt travel. This allows for a dramatically increased moment of inertia/resistance to shear and flexure. For example, replacing an 8 gauge, (0.148″ diameter cross rod with a flattened 0.148″×0.210″ rod gives a 38% increase in rod weight but with a 166% increase in camber resistance. Since the rods make up only nominally 10% of the weight of a belt but are a weak point for camber; the strength to weight ratio improves at even a higher rate. Alternatively, utilizing just a larger diameter cross rod also increases the thickness of the spirals and results in a larger weight gain, but yields a lower improvement in strength to eight ratio.

[0027] The rolled grain, structure of the rod 10 additionally increases the fatigue strength of the rods. The grain structure impairs crack migration, so even when the improved rod 10 eventually creeps it will also have a delayed fatigue failure not only due to the extra material through which the crack must propagate, but also the grain structure it must traverse. Simulations and tests suggest a nominal 30-40% improvement in fatigue life of components after camber takes place.

[0028] Referring also to FIG. 7, the flattened rod allows for a larger rear shear weld 14 in the double shear weld of a knuckleback conveyor belt 12 (an increase of nominally 40% in size). Multiple finite element analysis (FEA) models were run to determine the optimal angle of the knuckled edge components, (67 degrees), and the optimal size of the associated welds. An increase of fraying resistance of 25% is projected for the improved double shear weld.

[0029] In summary, the disclosure herein provides for the utilization of a cross rod that is roll formed into a flattened oblong shape with an elongated grain structure perpendicular to the shear load caused by the spirals engaging the rod in tension. The cross-sectional long, edges of the cross rods are parallel to the direction of belt travel. This allows for a dramatically increased moment of inertia/resistance to shear and flexure. Additionally, the rod also improves fatigue strength and life of the assembly, increases the strength-to-weight ratio and allows for a more fray resistant belt edge due to the larger shear welds.

[0030] While the disclosure herein has been described with respect to exemplary embodiments of the invention, this is by way of illustration for purposes of disclosure rather than to confine the invention to any specific arrangement as there are various alterations, changes, deviations, eliminations, substitutions, omissions and departures which may be made in the particular embodiment shown and described without departing from the scope of the claims.