Underground tail end hydraulic switch

The invention discloses an underground tail end hydraulic switch, and aims to solve the problem that, under the prior technical conditions in the field of petroleum exploitation, constrained by the horizontal section of a horizontal well and a deep well section of a well with a large slope, a test device at the tail end of an underground pipeline cannot be controlled by using a switch, and the bottom condition of the petroleum well cannot be tested is solved. The device comprises a shell, a ball seat hydraulic sliding sleeve assembly, a connecting plate, a push rod, and an opening and closingmechanism, the opening and closing mechanism comprises a valve core, a valve core control spring and a sleeve. In view of the defects in the prior art, the prior underground hydraulic control technology is used to provide a brand-new (improved) underground hydraulic switch without changing the prior petroleum well operation specifications. According to the invention, the on-off control of the switch of the test device at the tail end of the underground petroleum is achieved without changing the electrical drive environment, and the normal operation of the petroleum well is not affected. The device has the advantages of ingenious conception and reasonable design, is a brand-new exploration to the underground hydraulic switch structure, and has remarkable progressive significance on the petroleum well detection.