Abstract: A rotating module is provided and includes two rotating arms, and a bracket having a track groove and located between the two rotating arms. Each rotating arm includes a first rotating piece, a first end of which is located in the track groove; and a second rotating piece connected with the bracket and a second end of the first rotating piece respectively. In a folded state, a rotation center of the first rotating piece is a first position on the groove wall of the track groove; in an unfolded state, the rotation center of the first rotating piece is a second position on the groove wall of the track groove. The second position is located between a center position of the track groove and the first position, and the rotation center of the first rotating piece is one rotation center of the rotating arm.

Abstract: A rotating module is provided and includes two rotating arms, and a bracket having a track groove and located between the two rotating arms. Each rotating arm includes a first rotating piece, a first end of which is located in the track groove; and a second rotating piece connected with the bracket and a second end of the first rotating piece respectively. In a folded state, a rotation center of the first rotating piece is a first position on the groove wall of the track groove; in an unfolded state, the rotation center of the first rotating piece is a second position on the groove wall of the track groove. The second position is located between a center position of the track groove and the first position, and the rotation center of the first rotating piece is one rotation center of the rotating arm.

Abstract: A character parameters obtaining method for a displacement control mechanism of a hydraulic pump and a detecting device for carrying out the method are disclosed. The method involves constructing a hydraulic system; outputting hydraulic energy by the hydraulic pump driven by a primary motor; detecting pressure of a displacement control mechanism; obtaining middle parameters by obtaining the time required for preset change of the pressure at the output end of the displacement control mechanism; obtaining character parameters of the displacement control mechanism according to the middle parameters. The method can obtain the character parameters of the displacement control mechanism by the pressure detection, so that the performance of the displacement control mechanism can be judged according to the obtained character parameters.

Abstract: A character parameters obtaining method for a displacement control mechanism of a hydraulic pump and a detecting device for carrying out the method are disclosed. The method involves constructing a hydraulic system; outputting hydraulic energy by the hydraulic pump driven by a primary motor; detecting pressure of a displacement control mechanism; obtaining middle parameters by obtaining the time required for preset change of the pressure at the output end of the displacement control mechanism; obtaining character parameters of the displacement control mechanism according to the middle parameters. The method can obtain the character parameters of the displacement control mechanism by the pressure detection, so that the performance of the displacement control mechanism can be judged according to the obtained character parameters.