| 摘要 |
1412310 Piston packing ROBERT BOSCH GmbH 21 Feb 1973 [22 Feb 1972] 8423/73 Heading F2T A sealing means 11 for use in a compressed air cylinder 1 comprises a secondary sealing lip 14 and a port 16 leading to a cylinder space 9 at atmospheric pressure, the port 16 allowing limited leakage in the event of failure of a working sealing lip 13 in order to allow continued operation but give an indication of the failure. Air pressure acts on a piston 6 bearing the sealing means 11 and acts to increase the pressure of the lip 13 against the cylinder wall 12, compressed air normally being prevented from reaching as space 17 in front of the port 16. Alternatively, Fig. 3 (not shown), the port may take the form of a passage 16<SP>1</SP> in the piston 6. |
