METHOD OF FABRICATING AN ELASTOMERIC BLADE

Abstract

The present disclosure provides for a reinforced elastomeric blade having a plurality of laminated layers. The laminated layers can include at least two layers of elastomeric material at least partially separated by a fiber reinforced laminate layer or an embedded metal layer.

Claims

1. A method of fabricating a monolithic elastomeric blade composed of elastomeric material having oriented reinforcing fibers therein, the method comprising: providing a moldable preform of elastomeric material containing oriented reinforcing fibers; disposing the moldable and curable elastomeric material preform in a first portion of a mold cavity and extending into a chamber adjoining said mold cavity, the first portion of said mold cavity having adjoining thereto and communicating therewith a second portion of the mold cavity; displacing the moldable elastomeric material preform from the chamber, causing flow of the elastomeric material into the second portion of the mold cavity; reorienting, by the flow, the fibers in the elastomeric material flowing into the second portion of said mold cavity into a second fiber orientation direction, while leaving fibers in said first portion of said mold cavity as originally oriented; curing the elastomeric material preform, thereby forming a molded article; wherein the oriented reinforcing fibers comprise at least a first and a second laminated layer of fibers; and, the first laminated layer of fibers and the second laminated layer of fibers separated by elastomeric material therebetween.

2. A method of forming an elastomeric blade, using a mold equipped with compartments concentrically disposed relative to an elastomeric blade axis, (a) positioning a first elastomeric or rubber layer into the compartment of a hollow mold; (b) inserting a material (preform) web into the compartment, the material web including fibers oriented in a predetermined orientation; (c) displacing pistons towards an interior of the mold to allow for a material to flow into sidewall regions defining the mold; and (d) controllably reorienting the fibers at a shoulder region of the elastomeric layer by subjecting the elastomeric layer to a flow or shear action, wherein steps (a)-(d) fabricate an elastomeric blade having fibers oriented in at least two directions.

3. The method of claim 2 further comprising: iteratively repeating steps (a)-(d) for each additional layer.

4. The method of claim 2 further comprising: positioning the first layer at the auxiliary compartment of the mold in which the pistons are arranged; and moving the pistons in an axial direction of the elastomeric blade towards the mold.

5. The method of claim 2, wherein the predetermined orientation is a peripheral direction of the web.

6. The method of claim 2, wherein the reoriented fibers are in a random orientation.

7. The method of claim 2 further comprising: vulcanizing a section of the elastomeric blade not subjected to the flow; wherein the vulcanized section forms the first layer.

8. The method of claim 7, wherein the vulcanized section is formed from a mixture of polymeric material, the mixture including natural rubber and oil extended styrene butadiene mixed with fiber pieces.

9. The method of claim 8, wherein the fiber is at least 10% by weight of the mixture.

10. The method of claim 8 further comprising: selecting fiber pieces having a predetermined length for generating a desired modulus of elasticity; forming the first layer, wherein a length of the fiber pieces effects a density of the polymeric material and the density of the polymeric material effects a modulus of elasticity of the elastomeric blade.

11. The method of claim 10, wherein the modulus of elasticity increases with a length of fiber pieces in the mixture.

12. The method of claim 8, wherein the length of the fiber pieces is between 8 to 80 millimeters.

13. The method of claim 2, wherein the mold is formed from two mold halves and a mold core.

14. The method of claim 2, wherein the mold halves are equipped with ring-shaped compartments at a shoulder region of the elastomeric blade.

15. The method of claim 2 further comprising: incorporating the elastomeric blade in a snow plow blade assembly.

16. The method of claim 2 further comprising: incorporating the elastomeric blade in a rotatable drum for carrying associated ballast away from a conveyer belt.

17. The method of claim 16 further comprising: forming tines or teeth into edges of the elastomeric blade for fracturing the associated ballast.

18. A method for forming a snow plow blade assembly, the method comprising: forming an elastomeric layer from a mixture of rubber and fiber pieces; inserting the elastomeric layer into a compartment of a hollow mold; inserting a material web into the compartment; displacing pistons towards an interior of the mold to allow for a material to flow into sidewall regions of the mold; controllably reorienting the fibers of the elastomeric layer using the material flow to fabricate an elastomeric blade; and incorporating the elastomeric blade into a snow plow blade assembly.

19. A system for carrying ballast using an elastomeric blade formed from the method of claim 1, the system comprising: a conveyer belt for conveying associated ballast thereon; at least one rotatable drum for carrying the associated ballast above the conveyer belt; and at least one elastomeric blade spaced about the drum for lifting the associated ballast above the conveyer belt; wherein the at least one elastomeric blade diverts the associated ballast from the conveyer belt to a lower portion of the drum.

20. The system of claim 19, wherein the at least one flight is angularly offset to prevent the associated ballast from falling from the at least one flight when carrying the associated ballast in an upward direction above the conveyer belt.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG. 1 is a perspective view of a plow blade according to a first embodiment of the present disclosure;

[0031] FIG. 2 is a plan view of an elastomeric blade;

[0032] FIG. 3 is an exploded cross-sectional view of FIG. 1;

[0033] FIG. 4 is a perspective view of a plow blade according to a fifth embodiment of the present disclosure;

[0034] FIG. 5 is a cross-sectional view taken along section lines 5-5 in FIG. 4;

[0035] FIG. 6 is a perspective view of a first mounting bushing;

[0036] FIG. 7 is an exploded cross sectional view of a plow blade according to a fifth embodiment of the present disclosure;

[0037] FIG. 8 is a plan view of an adapter blade respectively;

[0038] FIG. 9 is a plan view of an elastomeric blade respectively;

[0039] FIG. 10 is a plan view of a clamp bar respectively;

[0040] FIG. 11 is a sectional view of a conveyance blade produced in accordance with the invention; and,

[0041] FIG. 12 shows elastomeric conveyance blades or portions thereof as produced in accordance with the teachings of this invention;

[0042] FIG. 13 shows another variety of elastomeric ballast conveyance blades;

[0043] FIG. 14 shows another embodiment of an elastomeric blade including two embedded metal reinforcements;

[0044] FIG. 15 shows an elastomeric blade having a single embedded metal reinforcement;

[0045] FIG. 16 shows an arrangement of plow wear parts including a separate backer scraper blade reinforcing the elastomeric blade component;

[0046] FIG. 17 is a side view of the assembled components of FIG. 17; and,

[0047] FIG. 18 is an exemplary reinforcement metal scraper blade including shape perforated sheet metal.

DETAILED DESCRIPTION

[0048] Referring to the figures, wherein a perspective view is shown of a plow assembly 10 displaying one aspect of the present disclosure. The plow assembly 10 includes a plow body 12 which is typically of hemispherical and funnel shaped steel construction for deflecting snow or other media. Plow assembly 10 is typically attached to a vehicle (not shown) by means of an appropriate frame or housing (also not shown). The vehicle may be any vehicle ranging from a standard car or pickup truck to a sand and salt-carrying dump truck to a road grader having a belly-mounted blade, to huge earth-moving or snow-moving plows, and to other ballast conveying machines. The means of attaching the plow body 12 to a vehicle may also typically include some form of hydraulic mechanism for positioning plow body 12 as desired, as is typical in the art. The plow assembly 10 may also include one or more reinforcing members to provide strength and rigidity to plow body 12. Reinforcing members are typically standard structural angles which are attached to the back of plow body 12, for example, by means of welding.

[0049] The plow assembly 10 can include at least one replaceable (or non-replaceable) plow body edge or mold board 16 mounted to the base of plow body 12 where edge 18 will contact the plowed surface, for example, a road surface. Mold board 16 is usually replaceable since its rigid construction is typically prone to damage due to abrasive contact with the surface being plowed or to obstacles, for example, pot holes, sewer covers, trees, mail boxes, and the like, encountered while plowing. Mold board 16 is typically of metallic construction, for example, steel construction, and is mounted to body 12 by a plurality of mechanical fasteners, for example, a plurality of nuts, bolts, and washers (not shown). Mold board 16 typically includes slotted perforations to allow for adjustment of the mounting of the mold board 16 during initial installation or for adjustment of the mounting of the mold board 16 after use and wear.

[0050] Referring again to the figures, a plow blade edge system 20 is therein displayed. Namely, an adapter blade 22 can be mounted to the mold board 16 of the plow body 12. The mold board 16 can be in a damaged or used condition. The adapter blade 22 includes mounting holes 24 aligned along a top edge 26 for securing to the mold board 16. The adapter blade 22 can be from about ¼ inch thick to about 1¼ inch thick and can be made from steel or similar materials. A bottom edge 28 along the adapter blade 22 can include high grade imbedded carbide inserts 30 along at least a portion thereof. To be described in more detail hereinafter, as a rubber blade 40 wears, or is damaged, the adapter blade 22, specifically the carbide inserts 30 along the bottom edge 28, act as a backup to resist wear until the rubber blade 40 can be flipped or replaced. It is to be appreciated that the adapter blade 22 can turn a damaged mold board 16 into a solid mounting surface for the rubber blade 40 or to protect a new mold board 16. In addition, the adapter blade 22 includes a series of bushings 34 aligned proximal to the bottom edge 28. The bushings 34 can be welded 35 to the front face 25 of the adapter blade 22. The bushings 34 provide a mounting arrangement for the rubber or elastomeric plow blade or edge segments 40. The bushings 34 provide a stable mounting platform that holds the plow edge segment 40 in a fixed position for ease of attachment between the adapter blade 22 and a clamp bar 60.

[0051] The dimensions of adapter blade 22 will vary depending upon the size of plow body 12 used, for example, the length of blade 22 is limitless, but reinforcing blade 22 typically will have a length from about 3 to about 12 feet. The width or height of blade 22 can be between about 3.0 to about 12.0 inches. For some exemplary embodiments, the length of individual segments of the adapter blade 22 can be 3, 4, 5, and/or 6 feet. In this manner, any combination of two, or three, blade segments can be combined to extend across plow blade 12 having a length of 6, 7, 8, 9, 10, 11 or 12 feet, or greater.

[0052] The elastomeric plow edge segment(s) 40 can comprise styrene butadiene rubber (SBR), polyurethane, polyethylene, polystyrene, and rubber. The elastomeric plow edge segment 40 can be pre-drilled, punched, or molded, including apertures 42 aligned with the bushings 34 of the adapter blade 22. The elastomeric plow edge segment 40 includes two mounting positions such that when first installed in a first position, a first edge 44 is presented to the road surface below. After the first edge 44 has worn to wear line 41, the elastomeric plow edge segment 40 can be dismounted from the plow blade edge system 20, reversed, and remounted such that the elastomeric plow edge segment 40 now is in a second position which presents a second edge 45 to the road surface below. Although not shown, it is to be appreciated that the second edge 45 can wear to a second wear line. Each wear line can be up to about 25% of the overall width or height of edge segment 40. More particularly, the distance 43 from the initial edge 44 to wear line 41 can be about 25% of the overall initial width 47 of plow edge segment 40. In this manner, the overall wear of edge segment 40 can be up to about 50% of the initial width. In one embodiment, the overall wear (i.e. width reduction) of edge segment 40 is from about 28% to about 50% after both edges 44, 45 have worn to their respective wear lines. Thus, the elastomeric plow edge segment 40 enables an extended life for improved performance and a decrease in material cost.

[0053] As shown in FIG. 3, the plow blade edge system 20 can be attached to the plow body 12 in a number of arrangements. A means of mechanical fastening, for example, a plurality of nuts 71, 77 and bolts 64, 76 as shown in FIG. 3 can be provided to fasten the clamp bar 60 to the adapter blade 22. The clamp bar 60 includes a series of holes 62 that align with the holes 42 and bushings 34 in the elastomeric plow edge segments and adapter blade segments, respectively. The clamp bar 60 gives support to the elastomeric plow edge segment 40 when plowing and provides a mechanism for keeping the elastomeric plow blade 40 firmly in place. It is to be appreciated that the clamp bar 60 can be reusable and provides a quick and easy method for changing or flipping the elastomeric blade 40 from the first position to the second position. The dimensions of the clamp bar 60 will vary depending upon the size of the plow edge used, for example, the length of clamp bar 60 is limitless, but clamp bar 60 typically can have a length from about 3 to about 12 feet. The width or height of clamp bar 60 can be from about 3.0 to about 7.0 inches. The thickness of clamp bar 60 can be from about 0.250 inches to about 1.250 inches. Exemplary lengths include 3, 4, 5, and 6 foot segments. As described above, any number of combinations of these exemplary lengths can be used to accommodate varying sizes of plow body 12.

[0054] Referring to FIG. 3, a first mounting arrangement kit 20 is therein shown and can include a plow bolt 64 extending through a countersunk hole 66 in a first side 68 of the clamp bar 60. As shown, the first side 68 of the clamp bar includes countersunk holes 66 about the mounting holes 62. The plow bolt 64 and nut 71 secures the clamp bar 60 with the adapter blade 22.

[0055] It is to be appreciated, that the elastomeric plow edge segment 40 can comprise any variety of heights and a variety of lengths. The dimensions of elastomeric blade 40 will vary depending upon the size of plow body 12 used, for example, the length of plow edge segment 40 is limitless, but edge segment 40 typically will have a length from about 3 feet to about 12 feet. The width or height of blade 40 can be from about 4.0 inches to about 12.0 inches. The thickness of blade 40 can be from about 0.50 inches to about 3.0 inches. The blades can comprise from about 2 to about 8 laminated layers (to be described in detail hereinafter). Exemplary embodiments include elastomeric plow blade segments 40 of 3, 4, 5, and 6 foot lengths. In this manner, any combination of two, or three, blade segments 40 can be combined to extend across mold board 16 of 6, 7, 8, 9, 10, 11, and 12 foot lengths, or greater. The aforementioned lengths of plow edge segments 40 provide ease of handling and ease of mounting to the adapter blade 22. The plow edge segments 40 can be easily handled and mounted by one person. The plow edge segments 40 can be planar or linear in orientation. In this manner the plow edge segments 40 retain a flat and planar orientation for ease of mounting. Elastomeric plow blade members heretofore known typically comprise segments cut off from a coiled storage means. A coiled configuration presents difficulties in trying to straighten and mount a curled or curved elastomeric plow blade segment.

[0056] Yet still another embodiment of a plow blade assembly 20A is shown in FIGS. 4-7, wherein an elastomeric plow edge or blade segment 340 can comprise a rectilinear shaped, or similar, configuration. The dimensions of elastomeric blade 340 will vary depending upon the size and type of plow body 12 used, for example, the length of plow edge segment 340 is limitless, but edge segment 340 typically will have a length from about 3 feet to about 4 feet. The width or height of the blade 340 can be from about 4.0 inches to about 12.0 inches. The thickness of blade 340 can be from about 0.50 inches to about 3.0 inches. Exemplary embodiments include elastomeric plow blade segments 340 of 3, 4, 5, and 6 foot lengths having 6.0 inch to 8.0 inch height, and 1.0 inch to 2.0 inch thickness. In this manner, any combination of two or more blade segments 340 can be combined to extend across plow bodies 12 having 6, 7, 8, 9, 10, 11, and 12 (et al.) foot lengths. To be described in more detail hereinafter, the aforementioned lengths of plow edge segments 340 provide ease of handling and ease of mounting with an adaptor blade 322 to mold board 16. The components in the plow edge kit 20A can be easily handled and mounted by one person. The plow edge segments 340 can be stacked, and staggered, one upon the other in a storage orientation. In this manner, the mounting faces of the plow edge segments 340 retain a generally planar or flat orientation for improved storage and handling arrangements, ease and efficiency of mounting, and improved performance. To be described hereinafter, the present disclosure provides a method of forming the elastomeric blade 340.

[0057] A means of mechanical fastening can be provided to fasten a clamp bar 360, the elastomeric blade 340, and an adaptor blade 322 to the mold board 16. The clamp bar 360 can include a series of holes 380, 382 that align selectively with the plurality of holes and bushings in the elastomeric plow edge segments 340, adaptor blade 322 segments, and the mold board 16, respectively. The bar 360 gives support to the elastomeric plow edge segment 340 when plowing and provides a mechanism for keeping the elastomeric plow blade 340 firmly in place. During mounting, the clamp bar 360 can be held in place adjacent to elastomeric bar 340 by mounting tabs (not shown). Opposing mounting tabs can be located on distal ends of the bar 360 to provide a temporary holding mechanism by placing the tabs in corresponding mounting holes (not shown) in elastomeric bar 340.

[0058] Plow blade edge or assembly kit 20A can be attached directly to mold board 16 as a complete system by means of mechanical fasteners, for example, a plurality of bolts 376, nuts 377, and plugs or bushings 378, as shown in the figures. Adaptor blade 322 can include a plurality of mounting holes 325, 326. Mounting holes 325 can be counter sunk and used for mounting the elastomeric blade 340 and the clamp bar 360 to the adaptor blade 322. Mounting holes 326 can be counter-sunk and provide the means, along with bolts 368 and nuts 369, for mounting the adaptor blade 322 to the mold board 16. It is to be appreciated that the adaptor blade 322 can come in varying lengths (i.e. 3, 4, 5, and 6 feet). The mounting holes 325, 326 can be equally spaced along the plow component segments.

[0059] Elastomeric blade 340 can include a slotted opening 379 for retention of the plug or bushing 378. As shown in FIG. 7, a plurality of slotted openings 379 are provided for retaining a plurality of bushings 378. Each bushing 378 can include at least two independent mounting holes 380, 382. The independent mounting holes provide adjustable mounting positions of the elastomeric blade 340 and the clamp bar 360. It is to be appreciated that independent mounting holes 380, 382 provide alternative mounting positions and a means for lowering the elastomeric blade 340 relative to the adaptor blade 322 as the elastomeric blade 340 is worn along a lower or working edge. It is to be further appreciated that a first mounting position 380 can be used for initial mounting of the elastomeric blade 340. As wear occurs to a bottom edge 343 of the elastomeric blade 340, the mounting of said elastomeric blade 340 can be moved to a second mounting position 382.

[0060] The clamp bar 360 can be easily removed and turned or flipped over which provides a quick and easy method for changing the position of and/or flipping the elastomeric blade 340 from one position to another position, while also providing another mounting position for clamp bar 360. As discussed above, the dimensions of elastomeric blade 340 and clamp bar 360 will vary depending upon the size of plow edge used, for example, the length of bar 360 is limitless, but bar 360 typically can have a length from about 3 feet to about 12 feet, preferably from about 3 feet to about 6 feet.

[0061] It is to be appreciated, that in use, elastomeric blade 340, and leg 341, will wear to the point that a bottom edge 343 of blade 340 will be proximal to a bottom edge 328 of adaptor blade 322 (in one mounting position). In this manner, edges 343 and 328 will generally be proximal to, or in contact with, the road or underlying surface. On one side, a length wise edge can comprise edge 343 proximal to the road or underlying surface. On another opposing side, and in another mounting orientation, a length-wise edge can comprise edge 345 proximal to the road or underlying surface (not shown).

[0062] It is to be appreciated that bar 340 can be mounted in at least four different positions and assembled with the clamp bar 360 and adaptor blade 322, and then mounted on mold board 16. A first position comprising mounting holes 380 include face 347 facing outward and edge 343 in a downward position. A second position includes face 347 facing outward and edge 343 in a downward position while utilizing the second mounting holes 382. A third position includes face 347 facing outward and edge 345 in a downward position while utilizing mounting holes 382. A fourth position includes face 347 facing outward and edge 345 in a downward position while utilizing mounting holes 380. The elastomeric blade 340 can thus be rotated length-wise to position each edge 343, 345 in two different positions, respectively, in order to enable even wear and to extend the life of elastomeric blade 340. The adaptor blade 322 can be premounted to mold board 16 and the assembly of plow blade edge kit 20A to simplify the changing of position of the elastomeric blade 340 as the blade 340 is worn along the respective edges 343, 345.

[0063] The bottom or working edges of the clamp bar 360 and adaptor blade 322 can provide hardened surfaces for engaging and disturbing hardened material (i.e. packed snow and ice) that are in the path (i.e. upstream) of the moving plow. The aforementioned arrangement provides the benefits of having hardened edges for breaking up material, and selectively presentable elastomeric blade edges 343, 345 for removing fluids and quieting the plow. The combination of hardened edge surfaces sandwiching edges 343, 345 provide the functional advantages of improving the movement of solid and fluid materials in the path of the plow blade while quieting and reducing the impact forces therefrom. Edge surfaces of the clamp bar 360 and the adaptor blade 322 can provide hardened edges upstream and downstream from edges 343, 345 thus providing the benefits of durability and wear resistance, while maintaining the benefits of an elastomeric edge.

[0064] Mounting holes can be aligned along the respective bars and blades 322, 340, 360 for receiving bolts 368, 376 and for mounting to mold board 16. The elastomeric blade 340 can be temporarily held in place by mounting bushings 378 and bolts 376 which can be aligned with corresponding mounting holes in elastomeric blade 340. The mounting bushings 378 are retained inside corresponding countersunk mounting openings 379 in elastomeric blade 340 for temporary retention to elastomeric blade 340. It is to be appreciated, that during mounting, bolts 376 can be passed (in turn) through adaptor blade 322, elastomeric blade 340, and clamp bar 360. Nuts 377 can then be fastened to bolts 376 for securing components 360, 340, 322 together.

[0065] As shown in FIG. 10, it is to be appreciated that a clamp bar 460 can be turned or flipped over which provides a quick and easy method for changing or flipping an elastomeric blade 440 (FIG. 9) from the first through the fourth positions. The clamp bar 460 can include a textured surface 462 on at least one face or both faces of the clamp bar 460. The textured surface 462 can include ribbing, texturing, diamond patterning, stud welding, cleating, knurling, et al. The textured surface 462 of the clamp bar 460 adheres to (i.e. ‘grabs’) the adjacent or mating surface 442 of blade 440 and provides for an increased surface area adhesion and friction between the adjacent surfaces of the clamp bar 460 and the elastomeric blade 440. In particular, the area below and around the mounting bushing 378 and mounting bolt 376, due to the increased surface adhesion, will have increased resistance to shearing, stretching, and tearing of the area of the elastomeric blade 440 around the mounting openings 479. It is to be appreciated that the increased friction, adhesion, or ‘grab’ of the mating surfaces of the clamp bar 460 and the elastomeric blade 440 distributes the shear forces evenly across the entire length of the blade 440. The result is a reduction to the concentrated forces pulling and stretching the blade 440 downward and away from mounting bolt 376 and mounting opening 479.

[0066] In a similar manner, an adaptor blade 422 (FIG. 8) can also include a textured surface adjacent to the elastomeric blade 440. The textured surface can include ribbing, texturing, diamond patterning, stud welding, cleating, knurling, et al. The textured surface 424 of the adaptor blade 422 adheres to or ‘grabs’ the adjacent or mating surface of blade 440 and provides for an increased surface area adhesion and friction between the adjacent surfaces of the adaptor blade 422 and the elastomeric blade 440. In particular, the area below the mounting bushing 378 and mounting bolt 376, due to the increased surface adhesion, will have increased resistance to shearing, stretching, and tearing of the area of the elastomeric blade around the mounting openings 379. It is to be appreciated that the increased friction, adhesion, or ‘grab’ of the mating surfaces of the adaptor blade 422 and the elastomeric blade 440 distributes the shear forces evenly across the entire length of the blade 440. The result is a reduction to the concentrated forces pulling and stretching the blade 440 downward and away from mounting bolt 376 and mounting opening 479. The combination of textured surfaces on both the clamp bar 460 and the adaptor blade 422 provides for increased adhesion on both the front and rear sides of elastomeric blade 440 thereby providing increased resistance to pulling, stretching, and/or shearing of the blade 440 away from the mounting bushing 378 and mounting bolt 376.

[0067] In one mounting position, one portion of the plow segment 440 can extend below clamp bar 460 and adaptor blade or plate 422, and another portion can extend above the clamp bar 460 and adaptor blade 422. The sandwiched elastomeric blade 440, i.e. sandwiched between selectively textured clamp bar 460 and selectively textured adaptor blade 422, associated with the mounting arrangement, reduces the “skipping” and stretching of the elastomeric blade 440 as the blade assembly is pushed across a surface. Adaptor blade 422, provides additional support to the back side of elastomeric blade 440 as the blade assembly is pushed across a surface. The alternative mounting arrangements and positions reduces the “moment arm” and distributes the shear forces of the elastomeric blade 440 about and along an entire mounting axis 400, and between respective mating surfaces of the adaptor blade 422, elastomeric blade 440, and clamp bar 460, while the assembly is engaged with and pushed along a surface. This reduction in “moment arm” and distribution of shear forces further reduces “skipping” and stretching of the elastomeric blade 440 while the blade edge 443 or 445 is engaged with and pushed along a surface.

[0068] Further in accordance with this invention, an elastomeric blade 540 (FIG. 11) is provided for plow blade edge systems which provide for improved longitudinal and lateral reinforcement and improved wear resistance while retaining sufficient flexibility to permit the blade to flex. Specifically, the elastomeric blades 540 of this invention can have a laminated structure comprising a plurality of elastomeric layers including a plurality of fiber reinforcement layers embedded within or laminated therebetween. The blade material in this arrangement results in a multiple layer structure including fibers distributed substantially throughout the length and width of the elastomeric blade 540.

[0069] It is an object of the present invention to provide an elastomeric blade 540, and method of forming same, comprising at least a first rubber, or similar, layer 542 having an upper surface and a lower surface, a second rubber, or similar, layer 552 having an upper surface and a lower surface, a third rubber, or similar, layer 562 having an upper surface and a lower surface where the second rubber layer 552 is disposed between the lower surface of the first rubber layer 542 and the upper surface of the third rubber layer 562. The elastomeric blade can further comprise at least a first fiber reinforced layer 544 disposed between the first rubber layer 542 and the second rubber layer 552, and a second fiber reinforced layer 554 disposed between the second rubber layer 552 and the third rubber layer 562. Although not illustrated, it is to be appreciated that the elastomeric blade can comprise at least a fourth rubber, or similar, layer including at least a third fiber layer disposed between the third rubber layer and the fourth rubber layer.

[0070] The at least first, second, and third rubber layers 542, 552, 562 can be initially unvulcanized such that the assembled laminate of at least three rubber layers 542, 552, 562 and at least two fiber reinforced layers 544, 554 described above can then be subsequently vulcanized using methods and equipment employed in the manufacture of rubber conveyer or transport belts. The tackiness of unvulcanized rubber will help to hold the layers in place during assembly, and vulcanization of the rubber layers 542, 552, 562 and fiber reinforced rubber layers 544, 554 will cause all of the individual layers to become a single monolithic body of rubber with the intermediate layers 544, 554 of fiber reinforcement embedded therein.

[0071] To be described in more detail hereinafter, the elastomeric blades 340, 440, 540 can be manufactured from materials which are readily available and inexpensive and can be processed by layered conveyor belt or plow blade manufacturing means such as adhesive joining or vulcanization. The methods of processing elastomeric blades 340, 440, 540 described herein increase the wear resistance of the material, while at the same time, decrease stretching and tearing of the elastomeric blade as the blade is pushed along a road, or similar surface.

[0072] Describing now the method of forming the elastomeric blade 340, 440, 540 by way of example, it is to be appreciated the method includes use of a hollow mold embodying two mold halves for the outside surfaces of the side walls of an elastomeric blade. Within these mold portions there can be arranged a mold core. The mold halves can be equipped at the shoulder region of the elastomeric blade with ring-shaped compartments concentrically disposed with respect to the elastomeric blade axis. Within the compartments, there can be arranged ring-shaped pistons which can be moved in the axial direction of the elastomeric blade towards the hollow elastomeric blade mold. The work surfaces of these pistons form a portion of such hollow elastomeric blade mold.

[0073] At the beginning of the elastomeric blade fabrication operation there are inserted into the compartment of the hollow elastomeric blade mold, a first elastomeric or rubber layer, and for the purpose of fixing such in position there can be provided any suitable and therefore non-illustrated support devices. There is then inserted a material (preform) web having fibers, filaments or the like, oriented in the peripheral direction of the article. Thereafter, pistons can be displaced towards the interior of the hollow elastomeric blade mold, so that additional material flows into the regions of the side walls of such hollow mold.

[0074] At the elastomeric blade shoulder region the fibers, following completion of the flow operation, are essentially in a random orientation so that a good transition zone is achieved. The above process can be repeated at least one or two more iterations.

[0075] For all the embodiments disclosed herein the dimensions and number of layers is dependent upon the desired laminate structure of the individual blade sections. For instance, the fibers or the like can be oriented in two superimposed layers in different directions so that there is obtained an approximately crosswise oriented assembly. In the case of elastomers which can be vulcanized, the hollow elastomeric blade mold can simultaneously serve as the vulcanization mold. A different orientation of the fibers at different elastomeric blade sections or portions can also be obtained by orienting fiber layers with appropriate differently oriented embedded fibers.

[0076] Elastomeric blade construction can embody one to four fiber reinforced layers. By virtue of this arrangement it is possible to construct the individual fiber layers so as to be thinner so that during fabrication it is possible to obtain a better orientation of the embedded fibers. The layers themselves can be produced in a well-known fashion by injection molding or calendering so that the degree of the fiber orientation is dependent upon the processing speed (flow velocity) and upon the cross-section.

[0077] In another embodiment, the exterior walls of the rubber mixture can include fibers, so that there can be obtained at the surface regions of the monolithic elastomeric blade structure improved surface shear, tear, and stretch resistance.

[0078] Now with reference to another embodiment of an elastomeric blade (not illustrated), beveled or chamfered arrangement can be molded by providing partial layers which possess a different width with respect to one another and are arranged in superimposed fashion so as to form a substantially step-shaped transition zone. The orientation direction of the fibers in this layer arrangement can be different throughout the monolithic blade structure.

[0079] Furthermore, by specially designing the hollow elastomeric blade mold, for instance by providing different designs for the dimensions and/or shapes, it is also possible in accordance with the teachings of this invention to produce asymmetrical elastomeric blades.

[0080] A first phase of the process includes layering and inserting semi-finished products for forming the monolithic elastomeric blade into the mold. The ends of this semi-finished product are located at the auxiliary compartments of the mold in which there can be displaceably arranged pistons or slide-shaped elements or sections.

[0081] During the second manufacturing step of phase these movable elements can be displaced towards the hollow compartment of the mold so that the working surfaces of these movable elements form at their terminal position portions of the hollow mold. The ends of the semi-finished product are displaced into the remaining hollow portion of the mold, resulting in a reorientation of the fibers.

[0082] Finally there will now be presented certain exemplary illustrations of specific examples for the purpose of even more fully explaining the teachings of the present invention:

Example 1

[0083] A natural rubber mixture is mixed in a kneader with 20% by weight polyester fibers having a length of 80 millimeters and possessing a titre in the range of from about 2.3 den to about 4.3 den. From this mixture there are drawn plates at the calendar and such can be vulcanized in a conventional way.

[0084] Such plates or layers are, for instance, utilized for the inventive forming of raw laminar elastomeric blade products. It has been found that even the strength in the lengthwise direction is sufficient owing to the improved uniformity since there is attained a uniform force distribution. Therefore, an elastomeric blade equipped with such fibers can exhibit improved wear resistance since there is available a larger surface for the adhesion between the rubber and the fibers. The rupture or breaking elongation attained with the inventive fiber layers in the transverse direction is considerably more advantageous for the behavior of the elastomeric blade than the considerable higher rupture elongation which prevails in the case of conventionally manufactured elastomeric blades, since with the last mentioned elastomeric blades there oftentimes is present too great an elasticity which is disadvantageous.

Example 2

[0085] In analogous manner as in Example 1 a rubber mixture formed on the basis of natural rubber and oil extended styrene butadiene rubber is mixed with fibers. The shorter the fiber pieces within the polymeric material containing the fibers, the greater the density of fibers within the polymeric material in order to achieve a desired modulus of elasticity. The greater the density of fiber filling in the polymeric material, results in a greater, or higher, modulus of elasticity. However, the mixture also becomes stiffer and is more difficult to work, and in the completely vulcanized condition generally produces an increased heat development. On the other hand, the modulus of elasticity also increases with the length of the fiber pieces at the polymeric material. An elastic modulus, or modulus of elasticity, is a number that measures an object or substance's resistance to being deformed elastically (i.e., non-permanently) when a force is applied to it. The elastic modulus of an object is defined as the slope of its stress-strain curve in the elastic deformation region. A stiffer material will have a higher elastic modulus. An elastic modulus has the form:

[00001]$\lambda .Math.\stackrel{\mathrm{def}}{=}.Math.\frac{\mathrm{stress}}{\mathrm{strain}}$

where stress is the force causing the deformation divided by the area to which the force is applied and strain is the ratio of the change in some length parameter caused by the deformation to the original value of the length parameter. If stress is measured in pascals, then since strain is a dimensionless quantity, the units of A will be pascals as well.

[0086] The average length of the fibers used in practicing the invention as disclosed herein is generally approximately in a range of 8 to 80 millimeters. In the case of high viscosity rubber mixtures it is approximately in the range of 15 to 40 millimeters and in the case of liquid rubber preferably can be in an amount in the range of 40 to 75 millimeters. Finally, it is mentioned that either before and/or during and/or after the flow operation the section or portion of the molded article not subjected to such flow operation can be pre-vulcanized.

[0087] The term “fibers” as used herein is employed in its broader sense and generally is intended to encompass not only fibers as such, but also yarns, threads, filaments, and the like.

[0088] Other embodiments and applications (FIGS. 12-13) of elastomeric blades can include conveyance blades or flights embedded with fibers either through an extrusion mixture having a random orientation of fibers or a laminated configuration comprising layers of rubber and fibers.

[0089] As shown in FIG. 12, a means 600 for selectively diverting ballast from a conveyor belt 620 into a selected one of a plurality of drums can include a plurality of support members, each mounted to the first frame within one of the drums and extending vertically from the frame over the first conveyor. At least one elastomeric conveyance blade 640 (i.e. formed as described above) is mounted to each support member for selected downward extension therefrom. When fully extended, each conveyance blade 640 is proximal to the upper surface of the first conveyor 620, whereby ballast conveyed thereon is diverted by the conveyance blade 640 from the first conveyor 620 to the lower portion of the casing. Each conveyance blade 640 can be individually operated and replaced to facilitate the loading of selected drums.

[0090] Elastomeric conveyance blades or flights 740 can be used, for example, in a spaced spiral configuration 700 to move and convey ballast from a drum container. As shown in FIG. 13, a drum 721, when rotated, carries ballast 714 on the flights 740 in an upward direction. The predetermined angular offset of the flights 740 from perfect radial extension facilitate the lifting of the ballast 714 above the first conveyor 718, whereupon reaching a predetermined point, the ballast 714 is gravitationally dumped from the flights 740 onto the first conveyor 718. The arcuate plate 737 prevents the ballast 714 from falling from the flights 740 before reaching the predetermined point above the first conveyor 718. The ballast 714 comprising gravel, broken stone, slag, etc., can be placed, for example, between and under the ties of railroad lines to give stability. It is to be appreciated, that the flexible elastomeric flights 740, or terminal ends therefor, provide for an enhanced conveyance of ballast, whereby a ‘wiper’ action is incorporated as the flights 740 move against the arcuate plate 737. It is also to be appreciated, that the elastomeric nature of the flights 740, or terminal ends, reduces vibration and wear of the flights 740 and arcuate plate 737. The reduced vibration also enhances user operation. The ‘wiper’ action also enables conveyance of smaller particulates of ballast.

[0091] The conveyance blades can include a series of tines or teeth formed into the edges (not illustrated). The mechanism can include a series of blades which can be convergingly tapered toward a centerline and adapted to be equipped with a plurality of removable elastomeric tines. Alternatively, the tines can comprise steel ripper tines that are provided with elastomeric tips at their distal ends. This can provide a mechanism which is aggressive for fracturing compacted and harder material, while allowing the ends to convey smaller and softer material. This type of arrangement allows for the tines to be individually replaced. The tines or teeth can be formed by water jets cutting the elastomeric blades into the desired shape. In one exemplary embodiment, the elastomeric blades can comprise 3 to 4 foot sections, and 1 to 4 inches in thickness. The elastomeric blades, vanes, or flights can be used to convey material out of a truck or ballast ‘regulator’ for depositing said material at a desired rate and location.

[0092] Referring now to FIG. 14, it is a further object of the present invention to provide an elastomeric blade 840, and method of forming same, comprising at least a first rubber, or similar, layer 842 having an upper surface 843 and a lower surface 845 and at least one reinforcement layer or insert 850, 852 embedded in the elastomeric blade 840. The integrated reinforcement insert(s) 850, 852 can comprise scraper elements of partial width having working edges 853, 855, respectively (FIG. 14). The inserts 850, 852 can be formed from expanded metal, metal grating, and/or shape perforated sheet steel and can be integrated during the vulcanization of the elastomeric blade 840. In another embodiment of an elastomeric blade 940 (FIG. 15), the integrated reinforcement layer can comprise a full insert 950 (FIG. 15) wherein the molded rubber includes an integrated scraper element of substantially the entire width of the molded rubber 942. The scraper element or insert 950 includes two working edges 953, 955 and can be comprised of expanded metal, metal grating, mesh, screen, diamond plating, and/or shape perforated sheet steel. It is to be appreciated that the elastomeric blades 840, 940 can be flipped to expose alternatively each working edge 843, 845, 953, 955, respectively, of the blades 840, 940.

[0093] Referring now to FIGS. 16 and 17, the scraper blade or reinforcement layer 950 can be separately provided and mounted between an elastomeric blade 340 and an adapter blade 922. In this manner, the scraper blade 952 provides ‘downstream’ support to the full width and length of the elastomeric blade 340 (FIG. 17).

[0094] FIG. 18 reflects one exemplary variety of a scraper blade or a reinforcement layer 952. FIG. 18 reflects an exemplary diamond plating or shape perforated metal reinforcement layer.

[0095] The exemplary embodiments have been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the exemplary embodiment be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.