Abstract: The present application discloses an electronic wristwatch with an easily adjustable rotating crown, comprising a watch case, and one side of the watch case is provided with a bezel, the other side is provided with a bottom cover, and the watch case is provided with a movement, the external side of the watch case is provided with a circular operation hole, and an adjusting gear is provided in the circular operation hole, the adjusting gear comprises a circular disk, and the side edge of the circular disk, which is close to the movement, is provided with a tapered row of teeth 1 along the circumferential direction, the side of the circular disk, which is away from the movement, is provided with a connecting post, and the free end of the connecting post is provided with a threaded post, the connecting post is externally sleeved with a crown tube.

Abstract: Disclosed is a blood pump device. The blood pump device includes: a housing having an overflow passage, and an inlet and an outlet respectively connected to the overflow passage; a rotor assembly rotatably disposed in the overflow passage; a coil disposed in a side wall of the housing; a first permanent magnet portion disposed inside the rotor assembly; a second permanent magnet portion disposed in the side wall of the housing, the first permanent magnet portion and the second permanent magnet portion forming a radial permanent magnet bearing; a piece of electric motor magnetic steel disposed inside a rotor of the rotor assembly; and a magnetic protection portion disposed at a periphery of the coil, wherein the magnetic protection portion and the electric motor magnetic steel act together to provide an axial pre-tightening force for the rotor assembly.

Abstract: Disclosed is a blood pump device. The blood pump device includes: a housing having an overflow passage, and an inlet and an outlet respectively connected to the overflow passage; a rotor assembly rotatably disposed in the overflow passage; a coil disposed in a side wall of the housing; a first permanent magnet portion disposed inside the rotor assembly; a second permanent magnet portion disposed in the side wall of the housing, the first permanent magnet portion and the second permanent magnet portion forming a radial permanent magnet bearing; a piece of electric motor magnetic steel disposed inside a rotor of the rotor assembly; and a magnetic protection portion disposed at a periphery of the coil, wherein the magnetic protection portion and the electric motor magnetic steel act together to provide an axial pre-tightening force for the rotor assembly.

Abstract: Provided is a chair comprising a seat; a backrest; a first armrest; a second armrest; a seat support structure; and a support structure for supporting the lower back of a seated person; wherein the support structure is directly mechanically-connected to the first armrest and the second armrest; and the support structure is not directly mechanically-connected to either the backrest or the seat. Additionally, provided are methods for supporting the lower back of a seated person in the need of such supporting comprising providing to the person a chair as described above.

Abstract: This invention teaches a chair comprising a seat; a backrest; a first armrest; a second armrest; a seat support structure; means for supporting the lower back of a seated person; a first slider; a second slider; a first slideway having a plurality of cavities; and a second slideway having a plurality of cavities, wherein the first slider and the second slider are disposed at two opposite ends of the means for supporting the lower back of a seated person; the first slideway is cooperating with the first slider and is connected to the first armrest; and the second slideway is cooperating with the second slider and is connected to the second armrest.

Abstract: This invention teaches a chair comprising a seat; a backrest; a first armrest; a second armrest; a seat support structure; means for supporting the lower back of a seated person; a first slider; a second slider; a first slideway having a plurality of cavities; and a second slideway having a plurality of cavities, wherein the first slider and the second slider are disposed at two opposite ends of the means for supporting the lower back of a seated person; the first slideway is cooperating with the first slider and is connected to the first armrest; and the second slideway is cooperating with the second slider and is connected to the second armrest.

Abstract: This invention relates to a chair comprising a seat; a backrest; a first armrest; a second armrest; a seat support structure; and means for supporting the lower back of a seated person; wherein said means for supporting the lower back of a seated person is directly mechanically-connected to said first armrest and said second armrest; and said means for supporting the lower back of a seated person is not directly mechanically-connected to either said backrest or said seat. The invention provides additionally methods for supporting the lower back of a seated person in the need of such supporting comprising providing to said person said chair.