HYDRAULIC CYLINDER Russian patent published in 2000 - IPC

FIELD: hydraulic cylinders used in hydraulic systems for regulation of counterbending of finisher work rolls of strip mills in capacity of counterbending hydraulic cylinders. SUBSTANCE: cylinder has plunger accommodated in its body whose movable joint with body cover has mud ring with sealing member located in cover. Plunger is made to form circular rod capacity in movable joint with body on the side of mud ring (sealing member). Plunger has two guides circular projections provided with corresponding sealing members. Formed between guide circular projections in movable joint with body on the side of supply of working pressure is additional circular closed cavity communicated with circular rod cavity by means of channel. In this case, volume of additional circular cavity exceeds that of circular rod cavity in any position of plunger. In preferable version volume of additional circular cavity is governed by conditions of provision of pressure variation compensation in circular rod cavity. EFFECT: prevented mechanical impurities from getting into circular rod cavity and movable joint between cylinder body and plunger to reduce wear of surfaces of plunger movable joint in cavity of hydraulic cylinder. 3 cl, 1 dwg