Please select the most similar patent number from A, B, C and D. Which number is?
An aircraft, comprising a main frame (100), a swing motor (200) and at least one pair of wings (300). The swing motor (200) outputs reciprocating swing motion, and has a swing arm (204) that is mounted on the main frame (100) and is capable of rotating around a fulcrum. The wings (300) are installed on the swing arm (204) of the swing motor (200) and may form a reciprocating fanning motion under the drive of the swing arm (204). The described aircraft employs a swing motor whose control circuit generates alternating pulses having adjustable pulse widths, so that the moving direction of permanent magnets changes alternately, thus forming a reciprocating swing. The swing motor does not experience stalling, automatically reduces swing amplitude when resistance is high or swing frequency is high, responds quickly to input signals, may achieve swing of various frequency modes, and may more realistically immitate the swinging pattern of wings of flying creatures such as birds and insects, thereby enabling the aircraft to form more enriched flight modes.
A: A diaphragm pump and an electric sprayer, and the diaphragm pump comprises a U-shaped yoke (100), four permanent magnets and an oscillating arm (400), wherein end faces (111, 121) of two legs (110, 120) of the U-shaped yoke can generate alternating magnetic polarities under the control of a control circuit (300). The four permanent magnets are fixedly mounted on an inner arm (420) of the oscillating arm by means of a second yoke (500). The four permanent magnets are a first permanent magnet (610), a second permanent magnet (620), a third permanent magnet (630) and a fourth permanent magnet (640), respectively, which are sequentially distributed in a same circumference centered at a pivot point. The first permanent magnet and the fourth permanent magnet are of the same polarity at radial end faces (611, 641); the second permanent magnet and the third permanent magnet are of the same polarity at radial end faces (621, 631), which is opposite to the polarity at the radial end face of the first permanent magnet. When the coil (200) is energized, the four permanent magnets generate torque in the same direction of rotation, and under the action of the alternating magnetic polarities at the end faces of the two legs of the U-shaped yoke, the four permanent magnets perform reciprocating oscillation; as a result, an outer arm (430) of the oscillating arm (400) brings a diaphragm push-and-pull rod (920) to squeeze the diaphragm, thus changing the size of a fluid chamber (910), thereby achieving intake and discharge of liquid.
B: A massaging motion apparatus and a head gripping massage device, the massage motion apparatus comprising a mounting base (100), a pair of swing arm assemblies (200) arranged opposite to one another, and a drive assembly (300), each swing arm assembly (200) being mounted on the mounting base (100), each swing arm assembly (200) comprising a rotating wheel (210) and a swing arm mechanism (220), each swing arm mechanism (220) comprising a swing arm (221) rotatably connected to the mounting base (100) by means of a first rotating shaft (510) and a connecting member (222) rotatably connected to the swing arm (221) by means of a second rotating shaft (520), a strip-shaped hole (2211) being disposed in the swing arm (221), the second rotating shaft (520) being arranged in the strip-shaped hole (2211), a guide groove (2101) being disposed in one wheel surface of the rotating wheel (210), the connecting member (222) comprising a connecting arm (2221) rotatably connected to the second rotating shaft (520) and a driven rod (2222) arranged in the guide groove (2101), and the connecting arm (2221) being connected to the rod side of the driven rod (2222). The two swing arms (221) in the pair of swing arm assemblies (200) of the present massaging motion apparatus simultaneously swing towards each other or swing away from each other, thereby implementing an opening and closing gripping motion that simulates human hands.
C: An aerial vehicle, relating to the technical field of flight. The aerial vehicle is characterized in: comprising wings (20) that provide flying power by means of up and down oscillation or vibration, and one-way air transmitting structures that only allow airflow to flow from above the wings (20) to below the wings (20) being distributed on the wings (20). Thus, in the process of the wings (20) repeatedly oscillating or vibrating, air flow is only able to flow from one side of the wings (20) to the other side of the wings (20), thereby acquiring lift for the aerial vehicle to fly.
D: An electric cleaning brush for cleansing a surface of a biological body, comprising: an oscillating motor and a brush driven by the oscillating motor. The oscillating motor comprises a U-shaped yoke (100), four permanent magnets and an oscillating arm (400). The U-shaped yoke (100) has coils (200) respectively wound around two legs thereof, allowing end faces of the two legs to generate alternating magnetic polarities under the control of a control circuit (300). The four permanent magnets are a first permanent magnet (610), a second permanent magnet (620), a third permanent magnet (630) and a fourth permanent magnet (640), respectively, which are sequentially distributed in a same circumference centered at a pivot point. The first permanent magnet (610) and the fourth permanent magnet (640) are of the same polarity at radial end faces; the second permanent magnet (620) and the third permanent magnet (630) are of the same polarity at radial end faces; the second permanent magnet (620) and the first permanent magnet (610) are of opposite polarities at radial end faces. The control circuit (300) generates alternating width-adjustable pulses, such that the permanent magnets form reciprocating oscillation; as a result, the oscillating arm (400) brings the brush to perform high-speed small-amplitude reciprocating oscillation, thus cleansing a surface of a biological body.
Answer: C