| 摘要 |
The system to position a mining prop (10), with a high pressure, has a piston cylinder (44) between the entry (40) and the exit (42). A ring zone (46) is at the entry side with a large surface and a ring zone (48) at the exit side has a smaller surface. A gas pressure spring (52) tenses the piston (50) towards the entry side. A bypass non-return valve (54), at the piston, is between the cylinder and the exit and between the ring zones to block the flow towards the entry. A pressure sensor (60) is connected to the exit. |
