ACCUMULATION-AND-RELEASE CONVEYOR

• US 20100193329A1
• Filed: 07/15/2008
• Published: 08/05/2010
• Est. Priority Date: 07/24/2007
• Status: Active Grant

• Current Assignee: Laitram LLC
• Original Assignee: Laitram LLC
• Inventors: Wargo, Stephen G., Fourney, Matthew L.
• Granted Patent: US 8,342,313 B2
• Time in Patent Office: Days
• US Class Current: 198/459.6
• CPC Class Codes: B65G 17/24 comprising a series of rollers which are moved , e.g. over a supporting surface, by the traction element to effect conveyance of loads or load-carriers
• CPC Class Codes: B65G 47/29 by temporarily stopping movement stopping elements B65G47/88

Abstract

An accumulation-and-release conveyor using a roller belt with rollers arranged to rotate in the direction of belt travel. The rollers extend through the thickness of the belt. A movable stop is positioned along the carryway just downstream of a bearing surface that is movable into and out of contact with the rollers. When the bearing surface is out of contact with the rollers, they are freely rotatable; when the bearing surface contacts the rollers, they roll on the bearing surface to propel articles in the direction of belt travel. The stop is selectively moved between a blocking position preventing articles from passing and accumulating them with low back line pressure on the freely rotatable rollers and a release position allowing articles to pass to the accumulation zone where they are propelled forward and separated from each other by the rotation of the rollers rolling on the bearing surface.

Claims

1. A conveyor comprising:

a conveyor belt advancing in a direction of belt travel from an upstream end to a downstream end, wherein the conveyor belt includes a plurality of rollers extending through the thickness of the conveyor belt and rotatable in the direction of belt travel;

a movable stop positioned along the conveyor and movable between a blocking position blocking conveyed articles and a release position allowing articles to pass;

a movable bearing surface disposed below the conveyor belt in a carryway zone extending from of the movable stop upstream and selectively movable into and out of contact with the rollers from below to cause the rollers to rotate by frictional rolling contact with the bearing surface when in contact with the rollers as the conveyor belt advances; and

wherein the rollers in the conveyor belt not contacting the bearing surface are freely rotatable.

2. A conveyor as in claim 1 further comprising a second like conveyor belt wherein both conveyor belts advance from the upstream end to the downstream end in the direction of belt travel in parallel across an intervening gap and are operated similarly to simultaneously convey an article spanning the gap.

3. A conveyor as in claim 2 wherein the movable stop moves through the gap.

4. A conveyor as in claim 1 wherein the movable stop and the movable bearing surface are disposed at the downstream end of the conveyor.

5. A conveyor as in claim 1 wherein the conveyor belt further includes axles retained in the belt perpendicular to the direction of belt travel and wherein the rollers are rotatable on the axles.

6. A conveyor as in claim 1 wherein the rollers on the conveyor belt are arranged in columns and further comprising belt support rails underlying the conveyor belt upstream of the movable stop in supporting contact with the conveyor belt between the columns of rollers.

7. A conveyor as in claim 1 further comprising:

one or more lane dividers disposed above the conveyor belt to divide the conveyor belt into parallel lanes extending in the direction of belt travel from the upstream end to the downstream end; and

one or more additional movable stops, disposed one stop per lane.

8. A conveyor as in claim 1 further comprising:

one or more conveyor belts as in claim 1 arranged in parallel to form parallel article-conveying lanes;

a movable stop for each article-conveying lane;

a common drive for all the conveyor belts to advance the conveyor belts in the direction of belt travel in parallel.

9. A method for conveying articles on a conveyor, comprising:

conveying articles atop article-supporting rollers in a conveyor belt advancing in a direction of belt travel upstream to downstream;

selectively moving a stop to block and release articles conveyed on the conveyor belt at a blocking position along the conveyor;

selectively moving a bearing surface into contact with the rollers in a carryway zone extending upstream from the blocking position to cause the rollers in contact with the bearing surface to propel articles atop the rollers forward along the advancing conveyor belt; and

coordinating the movement of the bearing surface with the movement of the stop.