| 摘要 |
1277421 Pneumatic springs GIRLING Ltd 21 May 1969 [21 May 1968] 24216/68 Heading F2S The piston-rod 6 of a pneumatic spring has a portion 11 of reduced cross-section which, during filling, is aligned with the piston-rod seal 4 thus allowing gas to flow into or out of the cylinder 1 without deformation of the seal. When filling is completed, an end fitting 8 is secured to the piston-rod 6 so as to cover the reduced portion 11 and prevent it becoming aligned with the seal 4 again. To charge the spring, the piston is bottomed on the end cap 2 bringing the groove 11 in the piston-rod opposite the piston-rod seal 4. Then the spring is placed in the apparatus shown and pressurized gas from a nipple N enters the cylinder 1 through a one-way valve L, a passage M, flats F, and the passage between seal 4 and groove 11. A quantity of hydraulic fluid may be provided in the cylinder of the spring for progressively damping the motion of the piston at the end of its stroke. In use, the unit may rotate between its illustrated position and an inverted position during extension and contraction. The hydraulic fluid passes to the lower end of the cylinder to damp the terminal portions of one or both strokes depending upon the quantity of fluid provided. |
