Roller belt with support edges

A modular conveyor belt with sturdy edges capable of supporting the weight of the belt along a carryway. The sturdy edges have bearing surfaces, such as the peripheries of wheels or the faces of wear pads, mounted at the sides of the belt to bear the belt's weight when the belt rollers are not supported on a roller-activation system.

BACKGROUND

The invention relates generally to power-driven conveyors and more particularly to conveyor belts with article-diverting rollers and support edges.

Conveyor belts having article-diverting belt rollers rotated by contact with rollers or flat surfaces in the carryway are used to sort, center, align, or otherwise divert conveyed articles. The belt rollers are arranged to rotate on their axes in a direction oblique or perpendicular to the direction of belt travel. The belt rollers protrude past the top and bottom surfaces of the belt. A roller-activation system in the conveyor carryway has contact surfaces that are selectively moved into and out of contact with the bottoms of the belt rollers. As the belt advances along the carryway in the direction of belt travel, the belt rollers rotate as they ride on the contact surfaces to divert articles atop the belt rollers. When contacting the belt rollers, the contact surfaces also support the belt along the carryway. When the contact surfaces are positioned out of contact with the belt rollers, the contact surfaces are not available to rotate the belt rollers or support the belt. In that situation the belt has to be supported in the carryway in another way. Examples of such roller belts are the INTRALOX® Series 7000 Transverse Roller belt and the Series 7050 Dual-Stacked Transverse Roller belt manufactured and sold by Intralox, L.L.C., of Harahan, Louisiana, U.S.A., and activated by the INTRALOX® S7000 Rack and Roll carryway. Such roller belts and roller-activation systems are described in U.S. Pat. Nos. 7,461,739; 7,506,751; 8,225,751; and 9,079,717.

SUMMARY

One version of a conveyor belt module embodying features of the invention comprises a module body that extends in a length direction from a first end to a second end, in a width direction from a first side to a second side, and in thickness from a top to a bottom. First belt rollers are mounted in the module body with salient portions protruding outward of the bottom of the module body to a first level. First and second edge portions are at the first and second sides of the module body. Each edge portion includes a bearing surface that extends to a second level between the first level and the bottom of the module body.

One version of a conveyor belt embodying features of the invention comprises a series of conveyor belt modules. Each belt module includes a module body that extends in a length direction from a first end to a second end, in a width direction from a first side to a second side, and in thickness from a top to a bottom. First hinge elements are spaced apart along the first end, and second hinge elements are spaced apart along the second end. First belt rollers are mounted in the module body with salient portions protruding outward of the bottom of the module body to a first level. First and second edge portions are at the first and second sides of the module body. Each edge portion includes a bearing surface that extends to a second level between the first level and the bottom of the module body. The first hinge elements of the conveyor belt modules are interleaved with and connected to the second hinge elements of adjacent ones of the conveyor belt modules to form an endless belt loop.

A conveyor embodying features of the invention comprises a carryway and a conveyor belt supported in the carryway. A first wearstrip in the carryway lies under the bearing surface on the belt's first edge portion, and a second wearstrip in the carryway lies under the bearing surface on the belt's second edge portion. A roller-activation system in the carryway has a contact surface that is movable from a first position in contact with the belt rollers to cause the belt rollers to rotate as the conveyor belt advances on the carryway to a second position out of contact with the belt rollers. The weight of the conveyor belt is borne by the roller-activation system in the first position and by the first and second wearstrips when the roller-activation system is in the second position.

DETAILED DESCRIPTION

One version of a conveyor belt module embodying features of the invention is shown inFIGS.1A-1D. The belt module20includes a module body22that extends in a length direction from a first end24to a second end25, in a width direction from a first side26to an opposite second side (not shown), and in thickness from a top28to a bottom29. Hinge elements30,31are spaced apart along the first and second ends24,25of the module body22. Lateral holes34through the hinge elements30,31receive a hinge rod (not shown). Belt modules20are linked together by interleaving the hinge elements30,31of the module with the hinge elements31,30of adjacent modules. Hinge rods received in lateral passageways through the aligned holes34of the interleaved hinge elements30,31connect the modules together at hinge joints.

Pairs of article-supporting belt rollers36extend outward of the top28of the module body22. The rollers36are partly or wholly above the level of the top28of the module body22. The article-supporting belt rollers36are mounted on axles38whose ends are supported in stanchions40. The axles38are parallel to the length direction of the module body22so that the rollers rotate in the width direction on the axles. Lower rollers42have salient portions that extend outward of the bottom29of the module body22. The lower rollers42are mounted on axles (not shown) within the module body between the top28and the bottom29. The lower rollers' axles are parallel to the axles38of the article-supporting rollers36. Each lower roller42contacts a pair of the upper article-supporting rollers36so that, when a lower roller is caused to rotate, its rotation in one lateral direction causes the contacting pair of upper rollers to rotate in the opposite lateral direction.

At each side26of the module body is an edge portion44. The edge portion44includes a mounting base46monolithically formed with the module body22. A detachable outermost edge member48attaches to retention structure50in the mounting base46. A hinge element49with a rod hole is formed at one end of the edge member48. Tabs52with shoulders snap in place in the mounting base46and are detachably retained by the retention structure50engaging the tab shoulders. A detachable wear pad54, also having tabs56with shoulders, snaps in place in the edge portion44and is retained by the tabs52of the detachable outermost edge member48. The wear pad54has a flat outer face58as a bearing surface that can slide along a wearstrip on the upper carryway path of a belt constructed of the modules20. The wear pad54is made of a durable, wear-resistant material, such as UHMW plastic. And for lower-friction sliding, the wear pad54can include PTFE. The salient portions of the lower rollers42extend to a level60below the level61of the face58of the wear pad54. The detachable outermost edge member48has a sloped outer side62that tapers inwardly toward the top28of the module body22. The taper can be linear or it can be concavely curved, to allow for placement of a side-off discharge close to the side of the module20.

Another version of a conveyor belt module is shown inFIGS.2A and2B. The module body22, the article-supporting rollers36, the lower rollers, and the wear pad54are the same as those inFIGS.1A-1D. The difference is that the conveyor belt module64has a detachable outermost edge member66that includes a freely rotatable edge roller68on an axle whose ends are supported by stanchions70. The axis of the axle is parallel to the axes of the axles of the pairs of article-supporting rollers36. The edge roller68, which is disposed outside of the outermost article-supporting roller36, is passive because it is not rotated by contact with a lower roller.

In a third version shown inFIGS.3A-3C, a roller-belt module72has wheels74that can roll along carryway wearstrips in low-friction rolling contact. The detachable outermost edge member76differs from the edge member66ofFIG.2Ain that it includes wheel wells78in a bottom side to accommodate the wheels74. The wheels74are mounted on parallel axles80whose axes are in the width direction so that the wheels rotate in the length direction. The ends of the axles80are retained in cavities82in the mounting base46at one end and in complementary half-cavities84,85in the mounting base and the detachable outermost edge member76at the other end. Salient portions of the lower rollers42extend to a level60below the level86of the periphery of the wheel74. The peripheries of the wheels74serve as bearing surfaces against a carryway wearstrip.

Yet another version of a conveyor belt module embodying features of the invention is shown inFIGS.4A and4B. The belt module88differs from the module ofFIGS.1A-1Din that it has an edge portion90monolithically formed with the module body92. Although the monolithic edge portion90is not detachable, a wear pad94with tabs96is. The tabs96allow the wear pad94to snap in place retained by locking structure98in the edge portion90.FIG.4Balso shows how the lower rollers42coact with the pairs of upper article-supporting rollers36to rotate them in a direction opposite to the direction of rotation of the lower roller they contact. The roller-to-roller interaction is the same for all the described versions of conveyor belt modules having both upper and lower rollers.

The conveyor belt module100ofFIGS.5A and5Bdiffers from the module inFIGS.4A-4Bin that it has a monolithic edge portion102with stanchions104at the top to support a passive edge roller68. Like the belt module ofFIGS.4A and4B, the belt module100includes structure to retain the detachable wear pad94.

FIGS.6A and6Bshow another version of a conveyor belt module with both upper and lower rollers36,42. The belt module106has a monolithic edge portion108that accommodates wheels74mounted on axles80whose ends are retained in cavities110,111in the edge portion.

Another version of a conveyor belt module embodying features of the invention is shown inFIGS.7A-7C. In this version the belt module112has a single layer of rollers114with salient portions that protrude past the top116and the bottom117of the module body118. The module112has an edge portion120that is monolithically formed with the module body118. Retention structure122in the monolithic edge portion120retains snap-in tabs124on a wear pad126in place. The roller114extends to a level below the level of the wear pad126.

The conveyor belt module128shown inFIGS.8A-8Cis the same as that inFIGS.7A-7C, except that it has a monolithic edge portion130that retains wheels74rather than a wear pad.

FIG.9shows a bottom view of a few conveyor belt modules112as inFIGS.7A-7Cconnected together at hinge joints131by hinge rods132received in lateral passageways formed by the aligned holes through the interleaved hinge elements134,135of adjacent belt modules. The modular conveyor belt is conventionally trained around drive and idle sprockets (not shown) whose teeth are received in drive pockets133in the bottom137of the belt between the rollers114. The drive sprockets are conventionally mounted on a drive shaft (not shown) rotated by an electric motor (not shown).

FIGS.10-12show a modular conveyor belt136constructed of belt modules112as inFIGS.7A-7Cin a sorting conveyor. InFIG.10the belt rollers114are activated to rotate in the direction of arrow138as they ride on the peripheries of freely rotatable activation rollers140in a roller-activation system while the belt136advances in a direction of belt travel142(out of the page inFIG.10). The activation rollers140rotate as indicated by arrow144on axes oblique to the direction of belt travel142and to the axes of rotation of the belt rollers114. Articles146atop the belt rollers114are pushed in the direction of arrow148to the left side of the belt. The activation rollers140, when raised as inFIG.10, also support the weight of the belt136in the carryway. Because the belt's wear pads126do not extend down as far as the belt rollers114, they only lightly contact or do not contact wearstrips150mounted at both sides of the carryway in the conveyor frame152.

To sort articles146off the opposite (right) side of the conveyor belt136, the roller-activation system, as shown inFIG.11, orients the axes of rotation of the activation rollers140at an oblique angle relative to the direction of belt travel142that is the mirror image of the oblique angle of the activation rollers inFIG.10. That causes the belt rollers114, as they roll along the activation rollers140, to rotate in the direction of arrow139, which pushes articles146toward the right as indicated by arrow151.

When the activation rollers140of the roller-activation system are lowered from their raised position inFIGS.10and11by an actuator (not shown) to a lowered position as inFIG.12, they are no longer in position to cause the belt rollers114to rotate. So an article146atop the belt rollers114remains stationary. And the conveyor belt136, whose weight is no longer supported by the activation rollers140, is supported by the wearstrips150on which the wear pads126at each side of the belt slide as the belt advances in the direction of belt travel142. Because the belt's outer edges bear the weight of the belt, wear-resistant wear pads126that are replaceable extend the useful life of the belt.

Although the invention has been described in detail in a few different versions, other versions are possible. Features such as wear pads, wheels, monolithic mounting bases, detachable edge portions, monolithic edge portions, passive edge rollers, single belt rollers, and upper and lower belt rollers may be combined in various other combinations than those described in detail. Furthermore, the belt rollers could be arranged to rotate on axes oblique to the direction of belt travel. And the roller-activation system could provide a flat surface on which the oblique belt rollers ride. The roller-activation system could provide carryway rollers whose axes of rotation are in the direction of belt travel. The roller-activation system, instead of raising and lowering the activation rollers into and out of contact with the belt rollers, could laterally displace the activation rollers or otherwise move the activation rollers from an activated position, in which they contact the belt rollers, and a deactivated position, in which they do not contact the belt rollers. So, as these few examples suggest, the scope of the claims is not meant to be limited to the exemplary versions used to describe the invention.