Conveyor chain

A conveyor chain having a series of links interconnected to form an elongated chain, each link comprising

• a pair of right and left inner link plates, said link plates having inner surfaces spaced apart on opposite sides of the chain, and having bush holes;
• a bush press-fitted into said bush holes, said bush having inner and outer circumferential surfaces;
• a roller rotatably fitted around the bush, said roller having inner and outer circumferential surfaces, wherein an annular area between the outer circumferential surface of the bush and the inner circumferential surface of the roller forms a bearing raceway extending between the inner surfaces of the inner link plates;
• a link pin inserted through said inner circumferential surface of said bush and having ends on each side of said chain;
• a pair of right and left outer link plates, each link plate being press-fitted to one of said ends of said link pin, said outer link plates linking said inner link plates to the inner link plates of an adjoining link in said series in the longitudinal direction of said chain;
• a plurality of bearing elements loosely inserted in said bearing raceway, and
• a pair of right and left thrust bearing annular members press-fitted to the outer circumferential surface of the bush disposed between the inner side surface of the adjacent inner link plate and the adjacent end surfaces of the bearing elements;
• and
• an annular sealing member for sealing lubricant oil within said bearing raceway, wherein the sealing element forms a sliding seal between the roller and one of the thrust bearing annular members and wherein the annular sealing member comprises an outer circumferential surface that is displaceable in a radial direction;
• wherein the outer circumferential surface of each thrust bearing annular member has a first diameter and an annular groove with a bottom having a second diameter, wherein the annular groove in the thrust bearing annular member receives the inner circumferential portion of the annular sealing member;
• and wherein the annular sealing member comprises an inner circumferential portion having a diameter larger than the second diameter and smaller than the first diameter,
• wherein in response to radial force on the roller, a portion of the seal is displaced radially inwardly into the annular groove, while a portion of the seal is displaced radially outwardly from the annular groove.

Conveyor chain having a series of links interconnected to form an elongated chain, each link comprising

• a pair of right and left inner link plates having inner surfaces spaced apart from one another and having bush holes;
• a pair of right and left outer link plates;
• a bush press-fitted into the bush holes, wherein the bush has inner and outer circumferential surfaces;
• a roller rotatable around the bush, wherein the roller has inner and outer circumferential surfaces, wherein an annular area between the outer circumferential surface of the bush and the inner circumferential surface of the roller forms a bearing raceway between the inner link plates;
• a link pin inserted through the bush and having ends extending through the inner link plates and outer link plates;
• a plurality of bearing elements in the bearing raceway, and
• a pair of right and left bearing retainers connected with the outer surface of the bush, forming side walls with the bearing elements disposed between the side walls;
• and
• a pair of right and left annular seals formed of elastomeric material to seal lubricant oil within the bearing raceway, wherein the right seal forms a fluid seal between the roller and the right bearing retainer and the left seal forms a fluid seal between the roller and the left bearing retainer and where each seal provides a sliding seal to retain oil within the bearing raceway while permitting lateral displacement of the roller relative to the retainers;
• wherein the right seal is seated in a groove in the right bearing retainer and the left seal is seated in a groove in the left bearing retainer and wherein a gap between the inner diameter of each of the right and left seals and the inner diameter of the grooves in the right and left retainers allows the right and left seals to be displaced radially without being substantially deformed in response to a radial load on the roller.