US-12617625-B2 - Apparatus and method for activating conveyor belt rollers

Abstract

Apparatus and method for activating conveyor belt roller assemblies by lowering and extending wearstrips to selectively lower the conveyor belt to place the conveyor belt roller assemblies into contact with actuating rollers. A wearstrip module housing the wearstrips includes an upper support upon which the wearstrips are mounted that is longitudinally and vertically movable relative to a lower support fixed relative to the actuating rollers. Mounting brackets rotatably mount the lower support and actuating rollers in a fixed position and orientation.

Inventors

• Andrew N. Baker
• Yorrick Mulder
• Paul Edward Kirkpatrick, JR.
• Jeffrey S. Schwai

Assignees

• LAITRAM, L.L.C.

Dates

Publication Date

20260505

Application Date

20220412

Claims (18)

1. 1 . A conveyor comprising: a conveyor belt advancing longitudinally in a direction of belt travel and having a plurality of article-supporting roller assemblies arranged in longitudinal columns and lateral rows, each roller assembly comprising an upper roller protruding above a top surface of the conveyor belt and a bottom roller for actuating the upper roller protruding below a bottom surface of the conveyor belt; longitudinally-extending wearstrips laterally offset from the columns of article-supporting roller assemblies and extending in the direction of belt travel below the conveyor belt; longitudinally-extending actuating rollers disposed at a fixed level below the conveyor belt and between the wearstrips and aligned with the columns of roller assemblies; and means for moving the wearstrips vertically and longitudinally into and out of supporting contact with the conveyor belt to selectively raise the conveyor belt out of contact with the actuating rollers.
2. 2 . The conveyor of claim 1 , wherein the wearstrips are mounted on a wearstrip module comprising an upper frame having side walls, wherein the wearstrips are mounted on upper edges of the side walls.
3. 3 . The conveyor of claim 2 , wherein the wearstrip module further comprises a lower frame housing an actuator that moves the upper frame vertically and longitudinally relative to the lower frame.
4. 4 . The conveyor of claim 3 , further comprising mounting brackets for mounting the longitudinally-extending actuating rollers, wherein the lower frame is fixed to the mounting brackets.
5. 5 . The conveyor of claim 4 , wherein the upper frame includes protrusions in bottom edges of the side walls terminating in downwardly angled edges.
6. 6 . The conveyor of claim 5 , wherein the downwardly angled edges extend below the bottom edges of the side walls.
7. 7 . The conveyor of claim 6 , wherein the lower frame comprises side walls having ramps at upper edges that are complementary to the downwardly angled edges.
8. 8 . The conveyor of claim 7 , further comprising a first set of low-friction inserts coupled to the downwardly angled edges and a second set of low-friction inserts coupled to the ramps, such that the first set of low-friction inserts slides over the second set of low-friction inserts.
9. 9 . The conveyor of claim 8 , wherein the low-friction inserts in the first set include an inner lip to prevent lateral movement of the upper frame relative to the lower frame.
10. 10 . A wearstrip module for selectively raising and retracting a set of wearstrips, comprising: a lower frame comprising a pair of lower side walls connected by a top wall, the lower side walls including ramps at upper edges; an actuator housed between the lower side walls; an upper frame comprising a pair of upper side walls connected by a bottom wall, the upper side walls including downwardly angled edges that protrude below the bottom wall, the upper frame connected to the actuator; longitudinally extending wearstrips coupled to top edges of the upper side walls; a first set of low-friction inserts coupled to the ramps; and a second set of low-friction inserts coupled to the downwardly angled edges, wherein the second set of low-friction inserts rest on the first set of low-friction inserts, so that longitudinal movement of the upper frame relative to the lower frame effects vertical movement of the upper frame relative to the lower frame.
11. 11 . The wearstrip module of claim 10 , wherein the ramps extend above the top wall of the lower frame.
12. 12 . The wearstrip module of claim 10 , wherein the second set of low friction inserts include inner lips to prevent lateral movement of the upper frame relative to the lower frame.
13. 13 . The wearstrip module of claim 10 , wherein the lower frame includes mounting means for mounting the wearstrip module to a mounting bracket.
14. 14 . The wearstrip module of claim 13 , wherein the lower frame includes extensions configured to be received in slots in the mounting bracket.
15. 15 . The wearstrip module of claim 10 , further comprising a connecting plate for connecting the actuator to the upper frame.
16. 16 . A method for operating an advancing conveyor belt having rows and columns of article-supporting roller assemblies extending through the thickness of the belt, the method comprising the steps of: deactivating the article-supporting roller assemblies by raising wearstrips into contact with portions of the conveyor belt between the columns of article-supporting roller assemblies to pull and raise the conveyor belt out of contact with actuating rollers mounted between mounting brackets, wherein the step of deactivating the article-supporting roller assemblies comprises moving an upper frame supporting the wearstrips relative to a lower frame housing an actuator, the upper frame comprising a pair of upper side walls for supporting the wearstrips, a bottom wall connecting the upper side walls and downwardly angled edges that protrude below the bottom wall; and activating the article-supporting roller assemblies by lowering the wearstrips relative to the mounting brackets, so that the article supporting roller assemblies contact the actuating rollers.
17. 17 . The method of claim 16 , wherein the lower frame comprises a pair of lower side walls connected by a top wall, the lower side walls including ramps at upper edges configured to abut the downwardly angled edges of the upper frame.
18. 18 . The method of claim 17 , wherein the lower frame comprises a first set of low-friction inserts coupled to the ramps and the downwardly angled edges include a second set of low-friction inserts that rest on the first set of low-friction inserts, so that longitudinal movement of the upper frame relative to the lower frame effects vertical movement of the upper frame relative to the lower frame.

Description

RELATED APPLICATIONS The present invention claims priority to U.S. Provisional Patent Application No. 63/186,976 entitled “Apparatus and Method for Activating Conveyor Belt Rollers” filed May 11, 2021, the contents of which are herein incorporated by reference. BACKGROUND The invention relates generally to power-driven conveyors and, more particularly, to conveyors having conveyor belts with article-supporting roller assemblies extending through the thickness of the belt. The article-supporting rollers are selectively activated by lowering and extending belt-supporting wearstrips to place lower conveyor belt rollers in contact with activating rollers in an activation assembly. The article-supporting roller assemblies are selectively deactivated by raising and retracting the wearstrips to bring them into contact with and raise the conveyor belt body away from the activating rollers. Modular plastic conveyor belts with article-supporting rollers extending through the belt are used in many package-handling conveyors, such as sorters, singulators, and diverters. The belt rollers are activated by bearing surfaces, such as flat wearstrips or roller arrays, underlying the belt on the carryway. As the belt advances along the carryway, the belt rollers rotate as they roll on the bearing surfaces. Articles atop the rollers are pushed along the advancing belt in a direction perpendicular to the rollers' axes of rotation, which may be parallel, perpendicular, or oblique to the direction of belt travel. In some applications, it is desirable to selectively activate and deactivate the belt rollers. This is conventionally done by moving, such as raising and lowering, the bearing surfaces into and out of contact with the belt rollers. But the bearing surfaces that have to be moved can be heavy or unwieldy and require a heavy motor or complex framework to make them move. SUMMARY These shortcomings are overcome by a conveyor embodying features of the invention. In one version, the conveyor comprises a conveyor belt advancing longitudinally in a direction of belt travel. The conveyor has article-supporting roller assemblies arranged in longitudinal columns and lateral rows. The roller assemblies include a top roller for contacting an article being conveyed and a bottom roller extending from the bottom of the conveyor belt for activating the top roller to selectively divert articles off the conveyor belt. The conveyor includes an activation assembly comprising freely-spinning actuating rollers that are fixed in position for selectively activating the bottom rollers and raisable and retractable wearstrips for pulling the conveyor belt away from the actuating rollers to deactivate the roller assemblies. According to one aspect, a conveyor comprises a conveyor belt advancing longitudinally in a direction of belt travel and having a plurality of article-supporting roller assemblies arranged in longitudinal columns and lateral rows, each roller assembly comprising an upper roller protruding above a top surface of the conveyor belt and a bottom roller for actuating the upper roller protruding below a bottom surface of the conveyor belt, longitudinally-extending wearstrips laterally offset from the columns of article-supporting roller assemblies and extending in the direction of belt travel below the conveyor belt, longitudinally-extending actuating rollers disposed at a fixed level below the conveyor belt and between the wearstrips and aligned with the columns of roller assemblies and means for moving the wearstrips vertically and longitudinally into and out of supporting contact with the conveyor belt to selectively raise the conveyor belt out of contact with the actuating rollers. According to another aspect, a wearstrip module for selectively raising and retracting a set of wearstrips comprises a lower frame comprising a pair of lower side walls connected by a top wall, the lower side walls including ramps at upper edges, an actuator housed between the lower side walls, an upper frame comprising a pair of upper side walls connected by a bottom wall, the upper side walls including downwardly angled edges that protrude below the bottom wall, the upper frame connected to the actuator, longitudinally extending wearstrips coupled to top edges of the upper side walls, a first set of low-friction inserts coupled to the ramps and a second set of low-friction inserts coupled to the downwardly angled edges. The second set of low-friction inserts rest on the first set of low-friction inserts, so that longitudinal movement of the upper frame relative to the lower frame effects vertical movement of the upper frame relative to the lower frame. According to another aspect, a method for operating an advancing conveyor belt having rows and columns of article-supporting roller assemblies extending through the thickness of the belt is provided. The method comprises the steps of deactivating the article-supporting roller assemblies by raising and ret