CN104260878A - Four-rotor aircraft rack with capacity of automatic folding and spreading - Google Patents

Abstract

The invention acquires design inspiration from a mechanical aperture tuning mechanism of a camera lens, and designs an automatic folding rack comprising a central worm and gear speed reduction motor, an upper center plate, a lower center plate, a crank, connecting rods, support arms and rotor baffles. Therefore, a four-rotor aircraft can be folded to a compact square structure under the driving of the motor distributed in the center of the rack, end parts of adjacent rotors are close to the peak of the square as far as possible, positions of the rotors are relatively fixed, and accordingly, the geometric dimensioning of the four-axis aircraft is greatly reduced; and the four-rotor support arms can be spread automatically when the central motor rotates reversely.

Description

Four-rotor aircraft frame that can be folded and unfolded autonomously

technical field

The invention belongs to the field of aircraft design, and in particular relates to a four-rotor aircraft frame capable of autonomous folding and unfolding. the

Background technique

Quadrotor aircraft is a relatively common and classic small aircraft, which is widely used in technical fields such as military reconnaissance, resource survey, and civil aerial photography. The aircraft is compact in structure and flexible in movement, and is suitable for use in narrow spaces or complex environments. However, the support arms of common quadrotor aircraft are mostly integral structures, and are integrated with the fuselage. The geometric size is relatively large, and it is not easy to carry. Even though some quadrotor aircraft adopt a foldable support arm structure to reduce the size of the structure, these structures require operators to fold and unfold them during use, causing inconvenience. In order to improve the convenience and flexibility in carrying, transporting, and using the quadrotor aircraft, it is necessary to develop a quadrotor aircraft support arm that can be folded and unfolded independently, and this support arm that can be folded and unfolded independently can be integrated with the quadrotor The aircraft frame is organically integrated to ensure the harmony, reliability and stability of the quadrotor aircraft in the overall structure. the

Contents of the invention

Inspired by the mechanical aperture tuning mechanism of the camera lens, the self-folding frame composed of the central worm gear motor, the upper and lower center plates, the crank, the connecting rod, the support arm, and the rotor baffle is designed, so that the quadrotor aircraft can be arranged Driven by the motor in the center of the frame, it is folded into a compact square structure. The ends of the adjacent rotors are as close as possible to the apex of the square. The position of the rotors is relatively fixed, thus greatly reducing the geometric size of the quadcopter. When the central motor is reversed, the four-rotor support arm can be independently deployed. the

Technical realization scheme of the present invention:

This self-folding and unfolding four-rotor aircraft frame is a single-degree-of-freedom system composed of a central worm gear motor, upper and lower center plates, cranks, connecting rods, support arms and rotor baffles. By controlling the positive and negative rotation of the motor arranged in the center of the frame, the support arm can be expanded and folded, and the self-locking effect of the worm gear motor can also be used to realize power-off self-locking to ensure the stability of the quadrotor aircraft frame structure . the

The folding frame adopts four sets of parallelogram mechanisms arranged symmetrically, and the crank is driven by the worm gear motor, so that the power is transmitted to the support arm along the crank and connecting rod, so that the four support arms rotate around the round hole on the edge of the center plate at the same time. When the four-rotor aircraft needs to unfold the support arm to fly, the motor rotates forward to drive the support arm to expand, and finally it is arranged in a "ten" shape. Difficult to fold. When the four-rotor aircraft needs to fold the support arm after flying, the motor reverses to drive the support arm to fold, and when the support arm is folded by designing a suitable angle, the limit buckle plays a role in limiting excessive folding. In addition, the rotor baffle can make the rotor at any angle. When the rotor starts to contact the rotor baffle, the rotor will adjust the angle adaptively under the reaction force of the rotor baffle. After the support arm is folded, the rotor returns to its original position. The bezel is basically flush. the

The connection between the support arm and the center plate is made of aluminum alloy. The shaft of the support arm and the hole on the edge of the center plate form a revolving pair. At the same time, the shaft can effectively withstand the bending moment generated here when the aircraft is flying. There are end caps on the top and bottom of the connecting piece to prevent the shaft from coming out of the hole. The support arm and motor seat are made of ABS plastic, which has higher strength, lighter weight and stronger vibration absorption capacity. the

In order to prevent the connecting rods from interfering, two pairs of parallel connecting rods are arranged in two planes respectively, and a short sleeve is used to ensure the stability of the connecting rods. The crank is composed of the upper crank plate, the middle crank plate, the lower crank plate and four small steel shafts. The output shaft of the motor and the three discs of the crank are connected by a profile connection in the middle, which can transmit large torque and has better impact resistance. Well, it can effectively improve the flight stability of the quadrotor aircraft. The limit buckle can limit the position of the support arm by limiting the position of the connecting rod, which can not only ensure that the support arm will not be excessively expanded, but also ensure that it will not be folded excessively. It also has the ability to lock the upper and lower center plates. tight effect. Near the crank in the center, there are four plastic locking posts, which are inserted into the studs to securely lock the upper and lower center pieces. the

Advantages of this system: When the support arm is unfolded and folded, the four sets of parallelogram mechanisms do not determine the position through movement, and the system is a single degree of freedom with high reliability; the worm gear motor is used, the torque is large, and the support arm is retracted Ziroom, at the same time, the motor speed is low, reducing the damage to the system caused by inertia; using the self-locking characteristics of the worm drive of the motor itself, it can realize self-locking when power is off, and it is not necessary to power on the motor during flight, saving energy, and After folding, the power will not be unfolded accidentally; the use of the rotor baffle can minimize the geometric size of the whole machine after the support arm is folded; the limit buckle can not only realize the double limit of the connecting rod, but also It can play a certain locking effect on the upper and lower center plates, one thing is multi-purpose, high efficiency, light weight; multi-mechanism and multi-unit integration, high integration, simple system, stable and reliable. the

Description of drawings

Fig. 1 shows that in an embodiment of the present invention, parallelogram mechanism axonometric view

Fig. 2 is an axonometric view of the support arm and the center plate in one embodiment of the present invention. the

Fig. 3 is an axonometric view of the rotor baffle and the limit buckle in one embodiment of the present invention. the

Fig. 4 is an expanded axonometric view of the overall structure in one embodiment of the present invention. the

Fig. 5 is an expanded top view of the overall structure in an embodiment of the present invention. the

Fig. 6 is a folded isometric view of the overall structure in an embodiment of the present invention. the

Fig. 7 is a folded top view of the overall structure in an embodiment of the present invention. the

Detailed ways

As shown in Figure 1-7, the quadrotor aircraft frame that can be folded autonomously is composed of a parallelogram mechanism in Figure 1; a support arm and a central plate part in Figure 2; and a system integrating rotor baffles and limit buckles in Figure 3. the

As shown in Figure 1, it is a parallelogram mechanism: 2 lower center plates, 3 crank upper discs, 5 short sleeves, 6 crank middle discs, 7 crank lower discs, 8 connecting rods, 11 connectors, 12 long steel shafts, and 13 long sleeves , 18 worm gear motors. The rack of parallelogram mechanism is determined by the connecting line of the center of 2 lower central plates and the axis of 11 connectors. The crank is composed of 3 crank upper plates, 6 crank middle plates, 7 crank lower plates and short steel shafts and short sleeves in the middle. The 8 connecting rods of the support arms A and B are between the 3 crank upper plates and the 6 crank middle plates. Plane; the plane between the connecting rod 8 of the support arms C and D between the middle disc 6 of the crank and the lower disc 7 of the crank, to avoid interference. the

As shown in Figure 2, it is the support arm, the center plate and its connectors: 1 upper center plate, 11 connectors, 14 end cover, 15 square tube, 16 motor seat, 19 brushless motor, 20 rotor. The support arm is composed of 11 connectors, 15 square tubes, and 16 motor seats. The 11 connectors are fixed with 14 end caps up and down to prevent the connectors from falling out.

As shown in Figure 3, it is the rotor baffle and the limit buckle: 9 limit buckles, 10 rotor baffles. The limit buckle is fixed on the upper and lower center plates to limit the position of the connecting rod and then limit the position of the support arm. The installation angle of the rotor baffle can be adjusted to suit the shape and size of the rotor. the

As shown in Figure 4-7, according to Figure 1-3, the parallelogram mechanism in Figure 1, the support arm, center plate and its connectors in Figure 2, the rotor baffle and the limit buckle in Figure 3 are integrated into one system. the

The above description is only a preferred example of the present invention, and does not limit the present invention in any form. All simple modifications made to the above embodiments according to the technical essence of the present invention, equivalent changes and modifications, all belong to the present invention within the scope of the technical program. the

Claims (5)

1. The four-rotor aircraft frame that can be folded and unfolded independently is characterized in that a symmetrically arranged parallelogram mechanism is used to transmit power to drive the support arm to fold and unfold, and the prime mover is a worm gear motor. Add limit buckle and rotor baffle to this system. the 2. The four-rotor aircraft frame capable of self-folding and unfolding according to claim 1 is characterized in that a symmetrically arranged parallelogram mechanism is used to transmit power, and the mechanism is not moved to an uncertain position throughout the whole process, so that the support arm is reliable Unfolding and folding, simple structure and light weight. the 3. The four-rotor aircraft frame that can be folded and unfolded autonomously according to claim 1 is characterized in that a worm gear motor is used as the prime mover, and the self-locking characteristic of itself can also be used to realize The support arm is locked after being unfolded and folded in place, and its low-speed nature is used to prevent it from damaging the structure of the quadrotor aircraft due to inertia. the 4. The four-rotor aircraft frame capable of self-folding and unfolding according to claim 1 is characterized in that the limit buckle can prevent the excessive expansion of the support arm and the excessive folding of the support arm by restricting the position of the connecting rod, so as to realize Double limit for two working conditions. the 5. The four-rotor aircraft frame capable of self-folding and unfolding according to claim 1 is characterized in that the rotor baffle is fixed on the upper center plate, so that when the support arm is folded, no matter what angle the rotor is at, it can Under the action of the rotor baffle, it turns into a state approximately parallel to the rotor baffle. Finally, the four rotors are connected end to end to form a square, saving space. the