APPARATUS AND METHODS FOR ACCELERATING CONVEYED ARTICLES

• US 20090008218A1
• Filed: 07/03/2007
• Published: 01/08/2009
• Est. Priority Date: 07/03/2007
• Status: Abandoned Application

• Current Assignee: Laitram LLC
• Original Assignee: Laitram LLC
• Inventors: Fourney, Matthew L.
• Application Number:
  US11/773,258
• Publication Number:
  US 20090008218A1
• Time in Patent Office: Days
• US Class Current: 198/412
• 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 47/28 during transit by a single conveyor

Abstract

A belt conveyor and a method for accelerating articles conveyed atop a moving conveyor belt. The conveyor belt includes rollers that are arranged to rotate on axes transverse to the direction of belt travel. The rollers have a large-diameter portion on which conveyed articles ride and one or more smaller-diameter portions that can be engaged by a bearing surface to rotate the rollers as the conveyor belt advances in the direction of belt travel. Articles atop the large-diameter portion are propelled in the conveying direction at a speed greater than twice the forward speed of the belt.

Claims

1. A conveyor belt comprising:

drive-receiving elements for receiving a driving force to advance in a direction of belt travel;

a plurality of rollers advancing with the drive-receiving elements and having axles defining axes of rotation transverse to the direction of belt travel;

wherein the rollers further include cylindrical first axial portions having a first diameter and second axial portions having a second diameter less than the first diameter.

2. A conveyor belt as in claim 1 wherein the second axial portions are cylindrical with a constant second diameter.

3. A conveyor belt as in claim 1 wherein the second axial portions are tapered with a linearly varying second diameter.

4. A conveyor belt as in claim 1 comprising:

first and second series of parallel chain links defining first and second sides of the conveyor belt and including the drive-receiving elements;

wherein the plurality of axles are supported at the first and second sides of the conveyor belt by the first and second chain links.

5. A conveyor belt as in claim 4 wherein the axles extend outward from opposite ends of the rollers.

6. A conveyor belt as in claim 1 wherein the rollers include third axial portions having a third diameter less than the second diameter.

7. A conveyor belt as in claim 1 further comprising stops periodically spaced along the conveyor belt.

8. A conveyor comprising:

a conveyor belt including a plurality of rollers;

a drive advancing the conveyor belt in a direction of belt travel along a conveying path;

wherein the rollers are arranged to rotate on axes transverse to the direction of belt travel and include;

cylindrical first axial portions having a first diameter; and

second axial portions having a second diameter less than the first diameter;

a first bearing surface contacting the second axial portion along a first stretch of the conveying path to cause the rollers to rotate at a first speed as the conveyor belt is driven along the first stretch in the direction of belt travel.

9. A conveyor as in claim 8 wherein the second axial portions are cylindrical with a constant second diameter.

10. A conveyor as in claim 8 wherein the second axial portions are tapered with a linearly varying second diameter.

11. A conveyor as in claim 10 wherein the first bearing surface is selectively positionable axially along the second axial portions.

12. A conveyor as in claim 8 wherein the speed s of an article supported atop the first axial portion of the rollers in the first stretch of the conveying path is given by:

s=v(1+d_A/d_B),

where v is the speed of the conveyor belt in the direction of belt travel, d_A is the first diameter, and d_B is the second diameter.

13. A conveyor as in claim 8 wherein the rollers include third axial portions having a third diameter less than the second diameter, the conveyor further including a second bearing surface contacting the third axial portions along a second stretch of the conveying path to cause the rollers to rotate at a second speed greater than the first speed as the conveyor belt is driven along the second stretch in the direction of belt travel.

14. A conveyor as in claim 13 wherein the second stretch is upstream of the first stretch along the conveying path.

15. A conveyor as in claim 8 wherein the first bearing surface is selectively movable into and out of contact with the second axial portions of the rollers.

16. A conveyor as in claim 8 wherein the conveyor belt further includes stops periodically spaced along the conveyor belt at positions at which articles propelled in the first stretch of the conveying path atop the first portions of the rollers are stopped from advancing farther along the conveyor belt.

17. A method for conveying articles, comprising:

supporting articles atop first axial portions of a series of rollers advancing at a first speed along a conveying path, wherein the first axial portions of the rollers have a first diameter;

contacting second axial portions of the series of rollers with a bearing surface in a first stretch of the conveying path as the series of rollers advances along the conveying path, wherein the second axial portions have a second diameter less than the first diameter, to rotate the rollers and propel the articles atop the first axial portions of the rollers along the first stretch of the conveying path at a second speed greater than twice the first speed.

18. The method of claim 17 further comprising contacting third axial portions of the series of rollers with a bearing surface in a second stretch of the conveying path as the series of rollers advances along the conveying path, wherein the third axial portions have a third diameter less than the second diameter, to propel the articles atop the first axial portions of the rollers along the second stretch of the conveying path at a third speed greater than the second speed.

19. The method of claim 18 wherein the second stretch is upstream of the first stretch along the conveying path.