Long roller slip conveyor
A slip roller conveyor has a frame comprising a pair of parallel, spaced-apart side plates. Secured to each of the side plates is a plurality of annular rollers with a predetermined pitch distance between adjacent rollers. The annular rollers have tubular sleeves of a lesser diameter projecting outward from a side surface thereof. The tubular sleeves on an opposed pair of annular rollers fit into the lumen of a longer tubular roller with a clearance fit. The annular rollers on each of the side plates are driven by an endless belt that also surrounds a motor-driven nose roller.
1. A slip roller conveyor module comprising:
(a) a frame including a pair of parallel, spaced-apart side plates extending a length dimension of said module;
(b) a plurality of slip rollers extending between the side plates in parallel, spaced-apart relation to one another, each of the slip rollers comprising
(i) a pair of annular pulleys, each of a first outer diameter and each with a concentric tubular sleeve projecting outward from one side surface of said pulleys, said sleeves having a second outer diameter that is less than the first outer diameter;
(ii) a pair of axle members extending individually through the tubular sleeves and the annular pulleys and affixed to said side plates;
(iii) a tubular roller extending between an opposed pair of annular pulleys rotationally secured on the pair of side plates by the axle members and having an internal diameter for surrounding the tubular sleeves thereof with a predetermined clearance fit there between;
(c) a first endless belt for engaging the pulleys affixed to the first of said pair of side plates and a second endless belt for engaging the pulleys affixed to the second of said pair of side plates; and
(d) means for driving said first and second endless belts at the same speed and in the same direction.
2. The slip roller conveyor as in claim 1 wherein the means for driving comprises:
(a) a motor mounted to the frame; and
(b) a nose roller journaled for rotation between said side plates, the nose roller including a pair of spaced-apart pulleys that engages the first and second endless belts and a further pulley driven by the motor.
3. The slip roller conveyor as in claim 1 wherein the endless belts are timing belts and the pair of annular pulleys each comprises sprockets with teeth for engaging the timing belts.
4. The slip roller conveyor as in claim 2 wherein the spaced-apart pulleys on the nose roller comprise sprockets with teeth for engaging the timing belts and the further pulley driven by the motor is also a sprocket having teeth for engaging a toothed belt coupling the motor to the further pulley on the nose roller.
5. The slip roller conveyor as in claim 1 wherein said axles comprise shoulder bolts screwed into threaded apertures in the side plates and the heads of the which engage free ends of the tubular sleeves.
6. The slip roller conveyor as in claim 1 wherein said predetermined clearance fit is in a range from about 0.005 inch to about 0.015 inch.
7. The slip roller conveyor as in claim 6 wherein the tubular roller has an outer diameter in a range from about ⅞ inch to 1¾ inch and are spaced apart equally on about 1″ to 2″ centers along the length dimension of the module.