Abstract: A sliding sleeve device has an outer cylinder, a circulation hole being provided in the wall of the outer cylinder; and an inner cylinder provided in an inner cavity of the outer cylinder. In an initial state, the inner cylinder and the outer cylinder are fixed to each other to seal the circulation hole. In a first state, the inner cylinder is movable relative to the outer cylinder, thereby unsealing the circulation hole. A protection mechanism is provided in the circulation hole, which has an inner member located on the radially inner side and an outer member located on the radially outer side.

Abstract: Provided are cell culture apparatus and method. The cell culture apparatus comprises a culture column and a perfusion system, the culture column comprising a first and a second tube-connecting caps and a support for cells to attach and grow thereon. The first and the second tube-connecting caps are respectively provided with a perfusion inlet and a perfusion outlet; The perfusion system comprises a culture medium storage device, a perfusion tube and a perfusion pump. A complete and closed culture column is formed in the cell culture device after the cells are inoculated, and the culturing is completed by the perfusion system to avoid contamination.

Abstract: Provided are cell culture apparatus and method. The cell culture apparatus comprises a culture column and a perfusion system, the culture column comprising a first and a second tube-connecting caps and a support for cells to attach and grow thereon. The first and the second tube-connecting caps are respectively provided with a perfusion inlet and a perfusion outlet; The perfusion system comprises a culture medium storage device, a perfusion tube and a perfusion pump. A complete and closed culture column is formed in the cell culture device after the cells are inoculated, and the culturing is completed by the perfusion system to avoid contamination.

Abstract: A light single button multi-function electric hammer comprises a body, a motor, a rotation set assembly, a cylinder assembly, a torque spring, a knob, a gearwheel and a transmission mechanism of torque clutch. The transmission mechanism comprises a pinion, a gear clutch, a middle shaft, a hammer crosspiece clutch, a swing rod bearing and a primary gear. The pinion is movably fitted with the middle shaft; the pinion meshes large end teeth of the gearwheel and matches with the inner teeth of the gear clutch. The gear clutch meshes small end teeth of the gearwheel and is fitted with the teeth shaft of the middle shaft. The gear clutch and the hammer crosspiece clutch are movably fitted with the teeth shaft of the middle shaft. The knob is connected with an operating mechanism linked to the large teeth end of the gearwheel, the gear clutch and the hammer crosspiece clutch.

Abstract: A light single button multi-function electric hammer comprises a body, a motor, a rotation set assembly (1), a cylinder assembly (6), a torque spring (2), a knob (26), a gearwheel and a transmission mechanism of torque clutch. The transmission mechanism of torque clutch comprises a pinion (7), a gear clutch (8), a middle shaft (10), a hammer crosspiece clutch (9), a swing rod bearing (11) and a primary gear (12). The pinion is movably fitted with the middle shaft; the pinion meshes the large end teeth of the gearwheel and matches with the inner teeth of the gear clutch. The gear clutch meshes the small end teeth of the gearwheel and is fitted with the teeth shaft of the middle shaft. The gear clutch and the hammer crosspiece clutch are movably fitted with the teeth shaft of the middle shaft. The swing rod bearing is movably fitted with the middle shaft and is connected with the cylinder assembly through the swing rod.