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: 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: A sliding sleeve opening tool includes an engaging element, a ball seat and a guiding head connected in sequence, as disclosed herein. The engaging element includes at least two elastic pawls uniformly disposed in a circumferential direction and at least one engaging part disposed on an external circumferential surface of an elastic pawl, and the engaging element is further provided with a first fluid channel which runs through the engaging element. The ball seat is provided with a second fluid channel which runs through the ball seat, and within the second fluid channel a taper hole section for bearing a sealing ball is disposed, the second fluid channel being in communication with the first fluid channel. The guiding head is provided with a third fluid channel which runs through the guiding head, and the third fluid channel is in communication with the second fluid channel.

Abstract: A sliding sleeve opening tool includes an engaging element, a ball seat and a guiding head connected in sequence, as disclosed herein. The engaging element includes at least two elastic pawls uniformly disposed in a circumferential direction and at least one engaging part disposed on an external circumferential surface of an elastic pawl, and the engaging element is further provided with a first fluid channel which runs through the engaging element. The ball seat is provided with a second fluid channel which runs through the ball seat, and within the second fluid channel a taper hole section for bearing a sealing ball is disposed, the second fluid channel being in communication with the first fluid channel. The guiding head is provided with a third fluid channel which runs through the guiding head, and the third fluid channel is in communication with the second fluid channel.

Abstract: A household laundry drying appliance includes a process air circuit in which process air is circulated to remove moisture contained in laundry; and a sensor placed in the process air circuit. The sensor has a head portion for detecting a predetermined parameter of the process air and a base portion for assembly. The head portion is encapsulated in a protecting structure. With the protection of the protecting structure, The head portion can be protected from water splashing thereon, and as a result, the accuracy of the sensor is effectively maintained and the evaluation of the dryness of laundry taken in consideration of the detecting value of the sensor becomes reliable.