Please select the most similar patent number from A, B, C and D. Which number is?
A vibration motor, relating to the technical field of vibration apparatuses, and comprising a motor. A right eccentric block is fixedly connected to a right shaft end of a motor shaft of the motor in the circumferential direction, a screw mandrel is arranged at a left shaft end of the motor shaft, and the screw mandrel is fixedly connected to the left shaft end of the motor shaft in the circumferential direction and movably connected in the axial direction; a screw cover is fixedly mounted on an end surface of a left eccentric block, and the screw mandrel is connected to the screw cover by means of a screw groove-boss structure. According to the vibration motor provided by the present invention, the screw mandrel is moved leftwards or rightwards in the axial direction, so that the screw cover is driven to rotate relative to the motor shaft in the axial direction, and the left eccentric block is driven to rotate relative to the motor shaft in the axial direction. Therefore, an included angle between the right eccentric block and the left eccentric block in the circumferential direction is changed, and the purpose of adjusting eccentricity and exciting force is achieved.
A: A propeller connection structure and an unmanned aerial vehicle. The connection structure comprises a motor rotor shell (1) and a propeller (2). The motor rotor shell (1) is provided with a connection part (11) for connecting the propeller (2). The propeller (2) is provided with a through hole (21) fitted with the connection part (11), and a groove (22) for preventing the connection part (11) from being disconnected from the propeller (2), a first angle being formed between the through hole (21) and the groove (22). An elastic mechanism (3) is sleeved outside the connection part (11), wherein the elastic mechanism (3) is, when the propeller (2) is installed, elastically compressed to enable the connection part (11) to turn freely, and abuts the groove (22) when being elastically recovered. The connection part (11) on the motor rotor shell (1) is fitted with the groove (22) of the propeller (2) to enable the propeller (2) to rotate at a high speed with a motor rotor, the propeller (2) is secured to the connection part (11) by means of the elastic mechanism (3), and the elastic mechanism (3) can cancel a loosening force generated by the high-speed rotation of the motor rotor, thereby attaining quick installation and detachment of the propeller (2).
B: A laminated screw type solid-liquid separator capable of achieving pendulum type movement, comprising fixed rings (1), movable rings (2), and a spiral shaft (3), the fixed rings and the movable rings that are staggered being provided in the radial direction of the spiral shaft; and further comprising a primary drive rod (4), a secondary drive rod (5), and a positioning rod (10). The primary drive rod is connected with an independent drive motor or connected with the spiral shaft by means of a transmission mechanism (6); the primary drive rod is supported by two or more support devices; the primary drive rod is provided with one or more eccentric devices; each eccentric device is connected with the secondary drive rod separately by means of a drive sheet (9); the secondary drive rod is sheathed at the lower ends of the movable rings to connect all the movable rings into a whole; the upper ends of the movable rings penetrate through the positioning rod, and the positioning rod drives, by means of a linear guide device (71), the upper ends of the movable rings to do vertical linear movement and the lower ends of the movable rings do pendulum type movement following the secondary drive rod simultaneously. According to the solid-liquid separator, supporting is achieved by a plurality of support devices, so that the problem of easy deformation of an eccentric shaft is resolved, and the wear between movable rings and the spiral shaft is reduced.
C: An eccentric vibrator, relating to the technical field of vibration machineries, and comprising an outer eccentric body (1) and an inner eccentric body (2). The outer eccentric body (1) has an inner circumferential surface. The inner eccentric body (2) has an outer circumferential surface. At least one first bearing (41) is provided between the inner circumferential surface and the outer circumferential surface. The gravity center of the inner eccentric body (2) and the gravity center of the outer eccentric body (1) both deviate from a rotation center formed by the first bearing (41). The outer eccentric body (1) is provided with a left bearing platform (10) which is coaxial to the first bearing (41), and a right end cover (3) is provided at the right side of the outer eccentric body (1) and the inner eccentric body (2). Compared with the prior art, the eccentric vibrator provided by the present invention can be used for adjusting the angle between the two eccentric bodies during rotation so as to adjust the excitation force and can also be used for adjusting the magnitude of the excitation force to zero in a dynamic state so as to reduce the load of a vibration exciter during start.
D: A power device (100) and an unmanned aerial vehicle (1000). The power device (100) comprises a motor (20) and a propeller (10) mounted on the motor (20). The propeller (10) comprises a propeller hub (11) and at least two propeller blades (12) connected to the propeller hub (11). The motor (20) comprises a stator assembly (22) and a rotor assembly (21) rotatable relative to the stator assembly (22). The rotor assembly (21) comprises a motor shaft (212), a housing (211) sleeved on the motor shaft (212) and rotatable with the motor shaft (212), and a magnet (213) provided on an inner side wall of the housing (211). The stator assembly (22) comprises a stator seat (221) sleeved on the motor shaft (212), an iron core (222) sleeved on the stator seat (221), and a coil (2221) wound on the iron core (222). The iron core (222) and the coil (2221) are accommodated in the housing (211), and are spaced apart from the magnet (213). The housing (211) comprises an opening portion (2114), and the propeller hub (11) covers the opening portion (2114). The invention prevents rain or dust from entering the internal part of a motor, and has good waterproof and dustproof performance.
Answer: C