| 摘要 |
The present invention relates to the devices of extension of telescopic crane boom. A hydraulic drive of telescopic crane boom has two hydraulic cylinders located in the boom cavity. The latter are connected to each other and turned by rods in opposite directions. A rod of hydraulic cylinder is connected to the root section, the rod of another cylinder - to the second mobile section. The rod cavities of both cylinders are directly connected. Sleeves of hydraulic cylinders are attached to the basis of the first movable section. In the rod of first cylinder by a tubular insert being fixed with respect to the rod a channel is made which is plugged from both ends with possibility of connection of the radial channel of rear cover of the rod and radial channel made in the wall of the rod, with rod cavity. In the end cap of piston cavity a unit of sequence with a central channel is made, hermetically augmented tubular channel passed through the center hole of the tubular insert with possibility of reciprocating movement of the tubular channel with hydraulic cylinder sleeve for the length of rod stroke and possibility of connecting the center channel of sequence unit with axial channel of the rear cover of rod. The central channel of sequence unit is intersected by diameter channels. On one side of the central axis the diameter channels are connected to the piston cavity of the channel, in which a spring-loaded valve with a cap at the opposite end is installed. The cap is located outside with possibility of interaction with a pusher attached to the end of the second cylinder rod. On the other side of the central axis between diameter channels a pressure valve is mounted. The piston cavities of hydraulic cylinders are connected through a sequence unit. The technical result is the reduction of energy costs of operation of hydraulic drive of telescopic crane boom at the expense of short-term, open-state pulse pressure valve during extension of the second mobile section.. |
