| 摘要 |
PURPOSE:To prevent packing movement or slipping-off between a slipoff preventive cylinder and a piston by fitting a dust seal and packing in the bore of the slipoff preventive cylinder at its outer end, and fitting a bearing and a stopper collar only at the inner end of the packing. CONSTITUTION:A slipoff preventive cylinder 4 is provided, wherein a seal groove 17 is formed for fitting of a dust seal 5 at the outer end, and a partitioning 18 is formed to be in tight fit on the periphery of a piston 3 in the backmost of the groove 17, and further a packing groove 19 is formed for fitting of a packing 6 in the backmost of the partitioning 18. A bearing fit part 22 in the spacing to admit fitting of bearing 7 in a plurality of places is formed in the part backmore than another partitioning 21, and at the foremost a stopper groove 23 is provided for fitting of a stopper collar 8. Because the bearing 7 is not installed at the partitioning 18, the bearing fit part 22 is not formed large. Accordingly there is no such fear that the packing 6 having received the oil pressure makes elastic deformation and movement, to allow the fluid bearing effect to be maintained good, with oil leak prevented, and thus the durability of the bearing 7 can be enhanced. |
