| 摘要 |
<p>A variable-lift driver comprises a driver housing (21), a driving cylinder (211), a lift control cylinder (220), a piston (30), a piston rod (31), a lift control cavity (221), a spring system (70), a first port (213), a second port (217), a driving switching valve (60), and a lift switching valve (90). A lift control sleeve (250) can slide in the lift control cylinder (220). The piston (30) can slide in the driving cylinder (211). The piston rod (31) can be connected to a second end surface (36) of the piston in operation mode and can slidably penetrate the lift control sleeve (250). The lift control cavity (221) is a fluid space between a second end portion (228) of the lift control cylinder and a second end portion (252) of the lift control sleeve. The first port (213) and the second port (217) are separately connected to a driving cylinder first cavity (232) and a driving cylinder second cavity (234) in fluid mode. The driving switching valve (60) comprises a working opening connected to the first port (213) in fluid mode. The lift switching valve (90) is connected to the lift control cavity (221) in fluid mode to control the lift control sleeve (250) to switch between a lift control cylinder first end portion (227) and the lift control cylinder second end portion (228). Accordingly, the variable-lift driver is controlled to be switched between a small lift and a large lift.</p> |
