Roller conveyor with clutched idler rollers

#The present invention relates generally to roller conveyors and, more particularly, to roller conveyors which are operable to accumulate articles thereon.

#Roller conveyors typically include a plurality of rollers mounted along and between a pair of opposite sidewalls of the conveyor. The rollers may be divided into zones, each of which may include a powered or driven or motorized roller and a plurality of idler or slave rollers interconnected to the powered roller. The rollers may be interconnected via a plurality of O-rings or bands which are wrapped around a pair of adjacent rollers. Because each idler roller may thus be connected to the powered roller via one or more bands, when the powered roller is deactivated and rotation stopped, the rotation of the connected slave rollers is also stopped via the O-rings. Packages or articles on the rollers thus cannot coast to a stop on the conveying surface. This substantially limits the ability of the conveyor to move the packages closer together while accumulating the packages at the zones of the conveyor. Also, starting and stopping of the rollers may cause slippage of the O-rings on the rollers, which may further lead to wear and eventual failure of the O-rings.

#The present invention provides a roller conveyor which is capable of conveying and accumulating articles and allowing the articles to coast on the rollers to compress the articles closer together along the conveyor. The present invention provides a roller conveyor having a plurality of rollers which include a clutch and which are drivable in one direction and which may coast or freely roll in the same direction when the drive means is deactivated or disconnected from the rollers.

#FIG. 1 is a perspective view of a roller conveyor in accordance with the present invention;

#FIG. 2 is a side elevation of a conveyor roller suitable for use with the roller conveyor of FIG. 1;

#FIG. 3 is another side elevation of the conveyor roller of FIG. 2;

#Referring now specifically to the drawings and the illustrative embodiments depicted therein, a roller 10 for a roller conveyor 11 includes a roller portion 12 and a drive portion 14 (FIGS. 1-3 and 5). The roller portion 12 is rotatable relative to a shaft portion 16, which is adapted for mounting the roller 10 to and between a pair of opposite sidewalls 13 of the conveyor 11. The drive portion 14 includes a one-way clutch device 18 (FIG. 5), which imparts rotation of the roller portion 12 in a driving direction to convey articles along the conveyor in a direction of conveyance. The clutch device 18 also allows drive portion 14 to rotatably drive roller portion 12, while allowing roller portion 12 to rotate relative to drive portion 14, such that the roller portion may continue to roll or coast relative to the drive portion 14 when the drive portion 14 is not rotating to drive the roller portion 12, as discussed below. In the illustrated embodiment, idler rollers 10 are idler or slave rollers and are generally rotatable relative to the shafts or axles 16 and the sidewalls 13 of the conveyor 11 in response to rotation or driving of a driven or powered or motorized roller 15 of the conveyor 11.

#As shown in FIG. 1, roller conveyor 11 includes at least two tandem zones (in the illustrated embodiment of FIG. 1, there are three zones shown generally at 11a, 11b, 11c, but the roller conveyor may have more or less zones, without affecting the scope of the present invention) for conveying articles therealong. Each of the tandem zones 11a, 11b, 11c, but includes a driven or motorized roller 15 and a plurality of idler rollers 10 mounted at and between the opposite sidewalls 13 of conveyor 11. The motorized roller 15 of each zone 11a, 11b, 11c may be independently operable from the motorized roller or rollers of the other zone or zones, and may be operable or controllable via a control 21. Control 21 may be operable to control the motorized roller or drive system of each zone, such as in response to an article sensor 17 positioned along each of the zones 11a, 11b, 11c, such as in the manner disclosed in U.S. patent application, Ser. No. 10/358,690, filed Feb. 5, 2003 by Cotter et al. for BELT CONVEYOR (Attorney Docket SIE04 P-100A), which is hereby incorporated herein by reference. The drive systems and/or motorized rollers of the zones thus may be operable to provide full contacting accumulation of articles on the rollers, as discussed below.

#Motorized roller 15 may be operable to rotate a driven roller portion 15a of the motorized roller relative to a shaft portion (not shown) of the motorized roller via an internal motor, such as a motorized roller of the types commercially available from various sources. For example, the roller may comprise a DC motorized roller, such as a 12 volt DC motorized roller or the like, or the motorized roller may comprise a 24 volt DC motorized roller or a 42 volt DC motorized roller or a 48 volt DC motorized roller or the like. It is further envisioned that the motorized roller may comprise other DC powered motorized rollers, or may comprise an AC powered motorized roller, without affecting the scope of the present invention. In the illustrated embodiment, motorized roller 15 is positioned between idler rollers 10 of the respective zone and is operable to rotatably drive the drive portions 14 of the adjacent idler rollers 10 via drive members or O-rings 19 which are drivably interconnected between motorized roller 15 and the adjacent idler rollers 10. The adjacent idler rollers 10 may rotatably drive other adjacent idler rollers via other drive members or O-rings 19 in a similar manner.