JP7481849B2 - Multicopter - Google Patents

Description

The present invention relates to multicopters, commonly known as "drones."

Multicopters are known that have multiple rotors (propellers) and can take off and land vertically. Multicopters were initially sold as toys, but they have gradually become more functional and are now being used for commercial purposes such as taking aerial photographs and transporting goods. Multicopters capable of manned flight are also being developed.

The frame structure of multicopters 100, 200 in the prior art is a branched type as shown in Fig. 17(a) or a radial type as shown in Fig. 17(b), with motor 106 and rotor 102 attached to the tip. That is, multicopters 100, 200 of the prior art have a rigid block portion 107 in the center, a rod-shaped frame member extends from said block portion 107, and motor 106 and rotor 102 are attached to the tip side of the rod-shaped frame member.
For example, in a multicopter with eight rotors, there are four trunk frames 103 arranged in a cross shape around a block portion 107 as shown in Figure 17 (a), and the tip of each trunk frame 103 branches into two, and a motor 106 is attached to the end of each branch portion 105.

When the multicopter 100 ascends or hovers, all of the rotors 102 are rotated at the same speed as shown in FIG. 18( a ).
When the multicopter 100 moves forward, as shown in FIG. 18B, the rotation of the front rotor 102 is relatively slowed down, and the multicopter 100 itself is put into a forward-leaning attitude.

When rotating the multicopter 100, every other rotor 102 is rotated at high speed and low speed, as shown in Fig. 18(c) . That is, the multicopter 100 itself is rotated by changing the rotation speed of adjacent rotors 102, such as a rotor with high speed rotation, a rotor with low speed rotation, a rotor with high speed rotation, a rotor with low speed rotation, etc.
Since each rotor 102 of the multicopter 100 normally rotates in the opposite direction to adjacent rotors, the attitude of the entire multicopter 100 can be rotated by alternately rotating each rotor at high speed and low speed as described above.

In the conventional multicopters 100 and 200, auxiliary equipment such as a storage battery and a receiver are mounted in the central block portion 107.
That is, in the multicopters 100 and 200 of the prior art, the central block portion 107 serves as an equipment mounting portion. The equipment mounting portion and the driving equipment, that is, the motor 106 and the rotor 102, are firmly connected by a rigid rod-shaped trunk frame 103 or the like. In the multicopters 100 and 200 of the prior art, the portion to which the driving equipment is attached and the equipment mounting portion are integrated in a rigid state.

JP 2018-129713 A

It is desirable for a multicopter to have a light overall weight in order to ensure a larger payload and to extend its range.
An object of the present invention is to provide a multicopter that can be made lighter.

The aspect for solving the above problem is a multicopter having a main body to which rotors are attached and an equipment mounting part to which auxiliary equipment is mounted, the main body has a plurality of connection parts, the equipment mounting part also has a plurality of connection parts, the connection parts on the main body side and the connection parts on the mounting part side are connected by a linear member, the equipment mounting part is suspended from the main body, and the length of the linear member between the connection parts on the main body side and the connection parts on the mounting part side can be changed during flight.

The auxiliary equipment is equipment other than a motor, and examples of the auxiliary equipment include electrical equipment such as a control device, a generator, a fuel tank, a camera, a lighting device, etc. It is not necessary for all the auxiliary equipment to be mounted on the equipment mounting section.
In the multicopter of this embodiment, the equipment mounting section is suspended from the main body section by a linear member.
Here, the linear member is a member such as a wire, rope, or string that can resist a tensile force but cannot resist a bending or compressive force.
Although linear members have low rigidity, they are extremely light in weight, which allows the weight of members that hold electrical equipment, etc. to be significantly reduced.
In addition, in the multicopter of this embodiment, the length of the linear member between the connection part on the main body side and the connection part on the mounting part side can be changed during flight. Therefore, it is possible to eliminate slack in the linear member. It is also possible to maintain the posture of the equipment mounting part.

In the above-mentioned aspect, it is desirable that at least one of the connection portions on the main body side and the connection portions on the placement portion side are engaged in a straddling state with a linear member, and that the linear member engaging with the connection portion on one side engages with one of the connection portions on the other side, and that the same linear member is further engaged with another connection portion on the one side.

In this embodiment, the length of the linear member between the connection part on the main body side and the connection part on the mounting part side is linked to the length of the linear members in other locations, making it easier to maintain the position of the device mounting part.

In the above-mentioned embodiment, it is preferable that the linear members are connected in a ring shape.

According to this embodiment, the length of the linear member is linked at more points, so the linear member is less likely to sag. Also, according to this embodiment, it is easier to maintain the position of the mounting member.

In each of the above aspects, it is desirable that the device mounting section be suspended from the main body section by a single linear member.

According to this embodiment, the length of the linear members is linked at even more points, making the linear members less likely to sag and making it easier to maintain the position of the mounting member.

In each of the above aspects, it is preferable that the main body portion has an annular support frame portion, and that the connection portion is directly or indirectly attached to the support frame portion.

In the multicopter of this embodiment, the main body has a ring-shaped support frame portion.
In the multicopter of this embodiment, adjacent rotors are directly or indirectly connected to each other by the support frame. Therefore, even if the rotation speeds of the connected rotors are different, the vertical displacement is suppressed by the horizontal connection part. In addition, because the support frame is annular, it is unlikely that only a part of it will be twisted.
Therefore, in a multicopter of this embodiment, the relative positions of all the rotors are unlikely to change during flight.
Therefore, the rigidity of the frame itself can be less than that of conventional frames, making it possible to reduce the weight.

Another aspect for solving the same problem is a multicopter having a main body to which rotors are attached and an equipment mounting part on which auxiliary equipment is mounted, characterized in that the equipment mounting part is suspended from the main body.

This type of multicopter can significantly reduce the weight of the components that hold auxiliary equipment such as electrical devices.

The multicopter of the present invention can reduce the weight of the frame and the overall weight.

FIG. 1 is a perspective view of a multicopter according to an embodiment of the present invention. FIG. 2A is a plan view of the multicopter of FIG. 1 , and FIG. 2B is a plan view of a multicopter of another embodiment. FIG. 2 is an explanatory diagram illustrating a model of the positional relationship between the rotors and the support frame of the multicopter in FIG. 1 . FIG. 2 is an explanatory diagram showing a model of the dynamic relationship between the rotor blades and the support frame of the multicopter in FIG. 1 . 1A is a front view of the rotor blade row of the multicopter of FIG. 1 during ascent and hovering, FIG. 1B is a side view of the rotor blade row when the multicopter of FIG. 1 is moving forward, and FIG. 1C is a front view of the rotor blade row when the multicopter of FIG. 1 is rotating. FIG. 11 is a perspective view of a multicopter according to another embodiment of the present invention. 13A and 13B are perspective views of a multicopter according to still another embodiment of the present invention. 7(a) and (b) are detailed views of the rib portion of the multicopter shown in FIGS. 7(a) and (b). FIG. 11 is a perspective view of a multicopter according to yet another embodiment of the present invention. 10A to 10C are explanatory diagrams showing the state of the hanging part when the multicopter in FIG. 9 is ascending and hovering. 1A is a perspective view of a multicopter according to still another embodiment of the present invention, and FIG. 1B is a plan view thereof. FIG. 13 is a plan view of a multicopter according to still another embodiment of the present invention. 13A, 13B, and 13C are plan views of a multicopter according to still another embodiment of the present invention. 11A and 11B are perspective views of a multicopter according to yet another embodiment of the present invention, in which (a) shows the main body in a horizontal position, and (b) shows the main body in an inclined position. 10A is a perspective view of a multicopter according to yet another embodiment of the present invention, FIG. 10B is a front view of the main body in a horizontal position, and FIG. 10C is a view of the main body in an inclined position. 11A is a front view of a multicopter according to yet another embodiment of the present invention, in which (a) is a front view of the main body in a horizontal position, and (b) is a view of the main body in an inclined position. 1A and 1B are perspective views of a multicopter according to the prior art. (a) is a front view of the rotor blade row of a conventional multicopter during ascent and hovering, (b) is a front view of the rotor blade row when the conventional multicopter is moving forward, and (c) is a front view of the rotor blade row when the conventional multicopter is rotating.

The embodiments of the present invention will be described further below.
The multicopter 1 of this embodiment is a drone equipped with eight rotors 2, and is remotely controlled by radio. The multicopter 1, like known drones, rotates the rotors 2 to generate lift from a downdraft and rises into the air. Also, by varying the rotation speed of each rotor 2, the drone can move in a direction having a horizontal component. In other words, by varying the rotation speed of each rotor 2, the drone can move laterally, diagonally up and down, and change its own attitude, among other movements.
The number of rotors 2 is not limited to eight, but may be three or more.

The multicopter 1 of this embodiment has a main body 3 and eight rotors 2.
The main body 3 has an annular support frame 10 , a rib portion 30 , an equipment mounting portion 11 , and legs 12 .
The support frame portion 10 is an endless annular portion made of resin etc. In this embodiment, the planar shape of the support frame portion 10 is circular as shown in Figs.
The rib portion 30 extends radially outward from the annular support frame portion 10 .

The device placement portion 11 is made of resin or other materials and is a rigid platform. The device placement portion 11 has a shape like a tray or a box and is rigid.
The equipment mounting section 11 is located at the center of a circle surrounded by the support frame section 10, and is connected to the support frame section 10 by a linear member 16. The linear member 16 used in this embodiment is, for example, a wire or a rope. That is, the linear member 16 can resist a tensile force like a wire, but cannot resist a compressive force or bending force, and cannot maintain its shape. For example, the linear member 16 can be a rope made of a fiber with high tensile strength, such as Kevlar (registered trademark).

In this embodiment, wires are used as the linear members 16, and the equipment mounting section 11 is suspended from the support frame section 10 of the main body section 3 by three wires. The equipment mounting section 11 hangs below the support frame section 10, and has a degree of freedom at least in the upward direction.

In this embodiment, the annular support frame 10 of the main body 3 has main body side connection portions 25a, 25b, and 25c. The device mounting portion 11 also has mounting portion side connection portions 26a, 26b, and 26c.
The main body side connection part 25a and the mounting section side connection part 26a are connected by a linear member 16a. Similarly, the main body side connection part 25b and the mounting section side connection part 26b are connected by another linear member 16b. Furthermore, the main body side connection part 25c and the mounting section side connection part 26c are connected by yet another linear member 16c. In this embodiment, the main body side connection part 25 is directly attached to the support frame part 10, but other members may be interposed therebetween. The same is true for the mounting section side connection part 26, which is directly attached to the equipment mounting part 11 in this embodiment, but other members may be interposed therebetween.

The leg portion 12 has leg members 15 that hang down below the support frame portion 10. In this embodiment, the leg portion 12 has four leg members 15 that are arranged at equal intervals.
The minimum ground clearance of the equipment mounting section 11 is higher than the minimum ground clearance of the legs 12 .
In the multicopter 1 of this embodiment, auxiliary equipment such as a storage battery 7 and a control device 8 are mounted on the central equipment mounting section 11.

1 and 2(a), in the multicopter 1 of this embodiment, the rotors 2 are attached to the annular support frame 10 via the rib portions 30. That is, in the multicopter 1 of this embodiment, the rotors 2 are indirectly attached to the support frame 10 via the short rib portions 30.
The rotor 2 is attached directly to the output shaft of a motor 20 in a known manner.
In this embodiment, the motors 20 are fixed to the upper parts of the rib portions 30 that protrude from the support frame portion 10 by mounting members (not shown). That is, the eight motors 20 are all fixed to the annular support frame portion 10 via the rib portions 30 so that the rotation shafts of the motors 20 are at a predetermined angle or in a predetermined posture with respect to the annular support frame portion 10.

In the multicopter 1 of this embodiment, adjacent rotors 2 are connected laterally by the support frame portion 10 via short rib portions 30, so that even if the lift of the rotors 2 varies in strength, the positions of some of the rotors 2 are unlikely to be noticeably displaced in the vertical direction.
In addition, since the motor 20 is supported on both the left and right sides by the support frame 10 via the short rib portions 30, it is also resistant to torsional moments.
In this embodiment, the motor 20 is directly fixed to the rib portion 30, which is cantilevered.
However, since the rib portion 30 protrudes from a relatively large annular support frame portion 10, the length of the cantilevered portion is shorter than that of the conventional branched structure (FIG. 17(a)) or the radial type (FIG. 17(b)).

Therefore, the deflection of the rib portion 30 is smaller than that of the conventional branched structure (FIG. 17(a)) or the radial type (FIG. 17(b)).
The relationship between the rotor 2 and the support frame 10 of the multicopter 1 of this embodiment is modeled as shown in FIG.
In the multicopter 1 of this embodiment, since the support frame portion 10 is annular, if the rib portion 30, the motor 20, and the rotors 2 are assumed to be integrated, adjacent rotors 2 etc. are directly connected laterally by the support frame portion 10. When modeled, the rotors 2 etc. can be said to be close to the state shown in FIG.
From this point of view, it can be said that the multicopter 1 of this embodiment has small relative displacement in the vertical direction due to the lift of the rotor 2.

The multicopter 1 of this embodiment, like known multicopters, ascends by driving the motor 20 to rotate the eight rotors 2. It also hovers at the ascended position.
When the multicopter 1 is ascending or hovering, the lift generated by each of the rotors 2a, 2b, 2c, and 2d shown in the figure is the same, as shown by the vectors indicated by the arrows in Fig. 5(a), and the eight rotors 2 maintain the same relative position and relative attitude as when unloaded (on the ground). For example, in the example of Fig. 5, the rotation shafts 21 of the rotors 2a, 2b, 2c, and 2d are all at the same height relative to the annular support frame 10, and can maintain an attitude perpendicular to the support frame 10.

When the multicopter 1 moves forward, as shown by the vectors indicated by the arrows in FIG. 5(b), the lift generated by the rear rotors 2c and 2d is stronger than that of the front rotors 2a and 2b among the rotors 2a, 2b, 2c, and 2d shown in the figure. As a result, the multicopter 1 assumes a slightly forward-tilted attitude as shown in FIG. 5(b). However, the eight rotors 2 maintain the same relative positions and relative attitudes as when unloaded, and are all lined up on the same inclined plane. The rotation shafts 21 of the rotors 2a, 2b, 2c, and 2d also maintain the same relative positions and relative attitudes as when unloaded with respect to the annular support frame 10. For example, according to the example in FIG. 5, the rotation shafts 21 of the rotors 2a, 2b, 2c, and 2d all maintain the same height position with respect to the annular support frame 10.

When rotating the multicopter 1 (changing its attitude in the direction of rotation), each of the rotors 2a, 2b, 2c, and 2d shown in the figure is controlled so that the lift generated is alternately stronger and weaker, as shown by the vectors indicated by the arrows in Figure 5 (c).
However, the multicopter 1 maintains a horizontal attitude as a whole, as shown in Fig. 5(c). The relative positions and relative attitudes of the eight rotors 2 do not change, and the rotors 2 are aligned on the same horizontal plane. The rotation shafts 21 of the rotors 2a, 2b, 2c, and 2d all maintain an attitude perpendicular to the annular support frame 10.

Here, it is important that the relative positions and relative attitudes of the rotors of the multicopter 1 do not change during flight.
As described above, in the multicopter 1 of this embodiment, the relative positions and relative attitudes of the rotors do not change during flight, and for example, the relative positions of all the rotors 2 are aligned on the same plane. Therefore, in the multicopter 1 of this embodiment, fine control by an attitude control device (not shown) and the like functions correctly as designed.

The multicopter 1 of this embodiment has a structure that is less susceptible to vertical displacement or twisting of each rotor 2, so the rigidity of the support frame 10 may be lower than that of the prior art. Therefore, the multicopter 1 of this embodiment can use a reduced amount of material or a material with a light weight per unit volume, thereby reducing the overall total weight.
Furthermore, the multicopter 1 of this embodiment is characterized by the support structure of the equipment mounting unit 11. That is, in this embodiment, the equipment mounting unit 11 is supported by being suspended from the main body unit 3 by a linear member (wire) 16.
The weight per unit length of the linear member (wire) 16 is extremely light compared to the weight per unit length of the support frame portion 10. Therefore, the weight of the support structure is light, and the total weight is light.

In addition, in this embodiment, the equipment mounting section 11 is suspended below the support frame section 10 and has some freedom in the upward direction, so the force acting on the support frame section 10 is simply the weight of the equipment mounting section 11. Therefore, the rigidity of the support frame section 10 does not need to be very high, which contributes to reducing the weight.

In addition, because the outer edge of the main body 3 of the multicopter 1 of this embodiment is annular, a large space can be secured inside. Therefore, the multicopter 1 of this embodiment can carry objects with a large volume.

Next, a description will be given of a preferred length of the rib portion 30. From the viewpoint of preventing changes in the attitude of the rotor blade 2 due to twisting or bending, it is desirable for the length of the rib portion 30 to be short.
On the other hand, from the viewpoint of effectively utilizing the descending air current to increase the efficiency of the rotor 2, it is preferable that the length of the rib portion 30 is long.
In other words, if the airflow generated by the rotor 2 hits any part of the multicopter 1, the lift generated by the rotor 2 will be attenuated. For this reason, it is desirable that no components of the multicopter 1 are within the range of the downdraft generated by the rotor 2.

Here, the connection portion of the rib portion 30 of the support frame portion 10 is "T" shaped and has a large planar area.
For this reason, it is desirable to design the length of the rib portion 30 so that the support frame portion 10 does not fall within the range of the downdraft generated by the rotor 2.
Specifically, as shown in FIG. 3( a ), it is desirable that the farthest portion of the rotation trajectory 31 of the rotor 2 does not overlap with the support frame portion 10 .
At least as shown in FIG. 3B, the farthest portion of the rotation trajectory 31 of the rotor 2 should overlap the inner line of the support frame portion 10, and the overlap between the rotor 2 and the support frame portion 10 should be small.
Of course, it is desirable that the farthest portion of the rotation trajectory 31 of the rotor 2 be located outside the inner line of the support frame portion 10 .

In the embodiment described above, the rotor 2 is mounted on the circular ring-shaped support frame 10 via the rib 30, but as shown in FIG. 2(b), the motor 20 and rotor 2 may be mounted directly on the ring-shaped support frame 10.

In the embodiment described above, the planar shape of the support frame portion 10 is circular, but it may be elliptical or polygonal as shown in FIG. 6. The support frame portion 10 shown in FIG. 6 is rectangular, but it may be triangular or polygonal with five or more sides. In any case, as long as it is an endless ring shape, the effects of the present invention can be achieved.

The support frame portion 10 and the rib portion 30 may be molded as a single unit, but it is also recommended to mold the support frame portion 10 and the rib portion 30 separately and then connect the two together.
7(a) and (b) show multicopters 5 and 6 in which the support frame portion 32 and the rib component member 23 are molded separately and then connected to each other.
The support frame portions 32 used in the multicopters 5 and 6 each have an annular portion 46 , and the rib attachment portion 33 is provided on the annular portion 46 .

8, an attachment portion 36 is provided at an end of the rib component 23. In this embodiment, the attachment portion 36 is a flange.
In this embodiment, the mounting portion 36 of the rib component 23 is fitted to the rib mounting portion 33 of the support frame portion 32, and the two are fixed together by screws.
The rib component 23 and the rib attachment portion 33 may be joined by any method, and may be joined by a temporary fastening element such as a screw, or by a permanent fastening element such as an adhesive.

As in this embodiment, the support frame portion 32 and the rib component member 23 (rib portion) are molded separately and then connected to each other, so that it is possible to manufacture multicopters of a variety of sizes using the support frame portion 10 as a common part. According to this embodiment, the interchangeability of parts is improved.
The multicopter 5 shown in FIG. 7( a ) is one embodiment in which a short rib component 23 is attached to a support frame portion 32 .
In contrast, a multicopter 6 shown in FIG. 7( b ) is one embodiment in which a long rib component 23 is attached to a support frame portion 32 and a large rotor 2 is mounted thereon.
In this way, according to this embodiment, multicopters 5 and 6 of different sizes can be made using a common support frame portion 32, thereby reducing the manufacturing costs of molds and the like.

In the multicopters 1, 5, and 6 of the above-described embodiments, electrical equipment (auxiliary equipment) such as a storage battery and a control device is mounted on the central equipment mounting section 11. In the multicopter 1, the equipment mounting section 11 is connected to the support frame sections 10 and 32 by linear members 16.

In the embodiment described above, the equipment mounting portion 11 is a member having rigidity, but the equipment mounting portion 11 may be a member having no rigidity. For example, the equipment mounting portion may be a net.
The multicopter 35 shown in FIG. 9 has a net (equipment mounting section) 41 made of fibers with high tensile strength, and the net 41 contains electrical equipment (auxiliary equipment) 42 such as a storage battery and a control device.
9 and 10, the net 41 is suspended from the support frame 10 by ropes (linear members) 40 made of fibers with high tensile strength. In this embodiment, the net 41 is suspended from the support frame 10 by three ropes (linear members) 40. Connections are not shown in FIGS. 9 and 10.
The electrical equipment 42 of the grid 41 and the motor 20 are connected by electrical wires (not shown).

When the multicopter 35 ascends or hovers, the net 41 hangs down from the center of the support frame 10, as shown in FIG. 10.

In the embodiment described above, the net 41 is suspended by the ropes 40 or the like, and the electrical equipment 42 is arranged inside the net 41 .
The equipment placed in the net (equipment placement section) 41 is not limited to the electrical equipment 42 .
For example, if the multicopter is a type that is equipped with a generator and drives the motor 20 with the power generated by the generator, auxiliary equipment such as an engine generator (generator) and a gasoline tank may be placed in the net 41. In addition, loudspeakers, fire extinguishing equipment, and cameras (including special cameras such as night vision cameras) may also be placed in the net 41.

In the embodiment described above, the plurality of rotor blades 2 are all the same size. However, the present invention is not limited to this configuration, and rotor blades of different diameters may be mixed.
A multicopter 50 shown in FIG. 11 has six rotors 51a, 51b, 51c, 51d, 52a, and 52b.
The pair of opposing rotor blades 52a, 52b are large, while the remaining four rotor blades 51a, 51b, 51c, 51d are small.

The small rotors 51a, 51b, 51c, and 51d are provided at positions spaced apart from each other by 90 degrees with respect to the center.
The large rotors 52a, 52b are positioned 180 degrees apart, and a 45-degree interval is secured between the adjacent small rotors 51a, 51d, 51b, 51c.
The intervals between the six rotors 51a, 51b, 51c, 51d, 52a, and 52b are not limited to the uneven angles as described above, and may be, for example, equal intervals.

In the multicopter 50 of this embodiment, the support frame portion 32 and the rib constituent members 53, 55 are molded separately and then connected together.
That is, the support frame portion 32 has an annular portion 46 , and six rib attachment portions 33 are provided on the annular portion 46 .
The six rib attachment portions 33 have the same shape and size, and are provided at predetermined intervals on the annular portion 46 .

In contrast, the rib constituent members 53a, 53b, 53c, 53d, 55a, and 55b include long and short rib constituent members.
That is, the rib constituent members 55a, 55b to which the large-diameter rotor blades 52a, 52b are attached are longer than the others.

In the multicopter 50 of this embodiment, the large diameter rotors 52a, 52b are mainly responsible for raising and lowering the multicopter 50 and keeping it in mid-air, while the small diameter rotors 51a, 51b, 51c, 51d are mainly responsible for attitude control.
Specifically, in the multicopter 50, the large rotors 52a, 52b are rotated at the same rotational speed in principle. That is, by rotating the rotors 52a, 52b at the same speed and at a high speed, the multicopter 50 ascends. By rotating the rotors 52a, 52b at the same speed and at a low speed, the multicopter 50 descends. Furthermore, by rotating the rotors 52a, 52b at the same speed and at an appropriate rotational speed, the multicopter 50 stops in midair.
In contrast, the rotation speed of the small rotors 51a, 51b, 51c, and 51d is precisely controlled, and the attitude is stabilized and the direction and attitude are changed to move forward and sideways.

In the above embodiment, four small rotors 51a, 51b, 51c, and 51d are provided, but the number of small rotors is not limited. However, it is preferable that the number of small rotors 51 is three or more.

The above control method is merely one example, and the rotational speed of each rotor may be controlled individually, as in a normal multicopter.

All six rotors 51a, 51b, 51c, 51d, 52a, and 52b may be rotated by a motor, or only the large-diameter rotors 52a and 52b may be driven by an engine.

In the multicopter 50 shown in Figure 11, the large diameter rotors 52a, 52b are located far from the center of the support frame portion 32, and the small diameter rotors 51a, 51b, 51c, 51d are located close to the center of the support frame portion 32, but the relationship of near and far may be reversed.
For example, as in the multicopter 80 shown in Figure 12, the large diameter rotors 52a, 52b may be located close to the center of the support frame portion 32, and the small diameter rotors 51a, 51b, 51c, 51d may be located far from the center of the support frame portion 32.

As an example of an embodiment in which rotors of different sizes are mixed, a support frame portion 32 and a rib component 23 are molded separately and then connected as shown in Figure 7, but the support frame portion 10 and the rib portion 30 may be integrated as in the multicopter 1 shown in Figure 1.

However, the configuration in which the support frame section 32 and the rib component members 53, 55 are molded separately has the advantage that a multicopter with a normal structure in which the rotor blades have the same diameter, and a multicopter with a mixture of rotor blades with different diameters can be manufactured with the support frame section 32 of a common structure. In other words, by attaching rotor blades 51a, 51b, 51c, 51d, 52a, 52b via rib component members 53, 55 of different lengths to a support frame section 32 with the same structure as a multicopter with a normal layout, a multicopter 50 with a mixture of rotor blades of different sizes can be manufactured, and this structure is suitable for a multicopter 50 with a mixture of rotor blades of different sizes.

In addition, in the multicopter 50 shown in Figure 11, the equipment mounting portion is formed of a net 41 and electrical equipment 42 is placed inside the net 41, but the equipment mounting portion may have another structure as exemplified above.
That is, parts of the configurations of the above-described embodiments may be replaced with each other, or parts may be omitted.

In the multicopter 50, the centers of the large-diameter rotors 52a and 52b are located farther from the center of the multicopter 50 than the centers of the small-diameter rotors 51a, 51b, 51c, and 51d. In other words, the multicopter 50 includes rotors at different distances from the center.
In the case where all the rotors are the same size, rotors at different distances from the center may be mixed.
13, the arrangement of the rotors is not uniform, and rotors at different distances from the center are mixed.
The multicopter 60 shown in FIG. 13(a) has eight rotors 63a to 63h.
The multicopter 60 has a circular support frame portion 32, and eight rotors 63a to 63h are attached to the support frame portion 32 via rib components 53.
In the multicopter 60, the six rotors 63a, 63b, 63c, 63d, 63e, and 63f are disposed at equal intervals on a pitch circle P that is concentric with the support frame portion 32. In other words, all of the six rotors 63a, 63b, 63c, 63d, 63e, and 63f are equally spaced from the center of the support frame portion 32.

Rotor 63g is disposed on an extension of rotor 63b, and rotor 63h is disposed on an extension of rotor 63e. The distance from the center of rotor 63g and rotor 63h is equal. However, the distance from the center of rotor 63g to rotor 63h is longer than the distance from the center of the other six rotors 63a, 63b, 63c, 63d, 63e, and 63f.

In the multicopter 60 , the four rotors 63 g , 63 b , 63 e , and 63 h are aligned on the same straight line CC that passes through the center of the support frame portion 32 .
The other rotors are arranged so that opposing ones are aligned on the same straight line passing through the center of the support frame portion 32.

It is desirable for the multicopter 60 to fly in a direction perpendicular to the row of the four rotors 63g, 63b, 63e, and 63h (straight line CC). In other words, it is desirable for the multicopter 60 to fly in the direction of the arrow in FIG.
In the multicopter 60 of this embodiment, the six rotors 63a, 63b, 63c, 63d, 63e, and 63f that are equally spaced on the pitch circle P are relatively close to the center of gravity of the whole. That is, in the multicopter 60, the rotors 63a, 63b, 63c, 63d, 63e, and 63f are installed at positions close to the center of gravity of the whole. Therefore, the multicopter 60 can smoothly yaw (rotate left and right).

Furthermore, in the multicopter 60 of this embodiment, the rotors 63g and 63h are relatively far from the center of gravity of the whole. That is, in the multicopter 60, the rotors 63g and 63h are installed at a position far from the center of gravity of the whole. Therefore, the multicopter 60 has good pitch (forward and backward) efficiency. In addition, roll (tilt to the left and right) is also stable.

Furthermore, the layouts shown in FIGS.
13B and 13C also have a circular support frame portion 32, and the support frame portion 32 has a rib attachment portion 33 provided on an annular portion 46. In the multicopters 61 and 62, there are rib attachment portions 33 to which no rib component member 53 is attached.

The rib component 70 used in the multicopters 61 and 62 has branch portions 72 at the tip of a main trunk portion 71, and a rotor 2 is attached to each rib component member 70. The rib component member 70 is formed by integrally molding the main trunk portion 71 and the branch portions 72, but the two may also be molded separately and joined in a later process. In other words, a rib component member of the main trunk portion 71 that constitutes a part of the rib and a rib component member of the branch portions 72 that constitute a part of the rib may be joined by screws or the like.
Multicopter 61 has rotors with different diameters.

The multicopters 50, 60, 61, and 62 shown in Figures 11 and 13 also have a net (equipment mounting part) 41, which is suspended from the support frame part 32 by ropes (linear members) 40. In these multicopters 50, 60, 61, and 62, the net (equipment mounting part) 41 is suspended from the support frame part 32 by four ropes (linear members) 40. The connection parts are not shown in Figures 11 and 13.

In the embodiment described above, the main body side connection parts 25a, 25b, 25c, etc. of the main body part 3 and the mounting part side connection parts 26a, 26b, 26c, etc. of the equipment mounting part 11 are connected by one linear member 16a, 16b, 16c, respectively. In the embodiment described above, the main body part 3 and the equipment mounting part 11, 41 are connected at three or four points, but the number of connection points is arbitrary.
However, in consideration of balance, it is recommended that the main body and the equipment mounting part be connected at three points.
In the above embodiment, the upper and lower connection parts 25, 26 are each connected by a single linear member, but the present invention is not limited to this configuration, and the main body side connection parts 25a, 25b, 25c and the mounting part side connection parts 26a, 26b, 26c of the equipment mounting part 11 may be connected by a plurality of linear members. For example, one mounting part side connection part 26a may be connected to two main body side connection parts 25a, 25b.

In the embodiment described above, the length of the linear member connecting the top and bottom does not change, but by adding a function to automatically change the length, it is possible to eliminate slack in the linear member and stabilize the posture of the equipment mounting section 11.
For example, by connecting all of the main body side connection parts 25a, 25b, 25c and the mounting section side connection parts 26a, 26b, 26c with a single linear member 73 connected in a ring shape, the length of the linear member between the main body side connection part and the mounting section side connection part can be automatically changed during flight to take up slack in the linear member and stabilize the posture of the equipment mounting section 11.

Below, with reference to Figure 14, we will explain a multicopter in which all of the main body side connection parts 25a, 25b, 25c and the mounting part side connection parts 26a, 26b, 26c are connected by a single linear member 73 connected in a ring shape.
14, like the above-described embodiments, the annular support frame 10 of the main body 3 has main body side connection parts 25a, 25b, and 25c. The equipment mounting part 11 also has mounting part side connection parts 26a, 26b, and 26c.
In the multicopter 65 of this embodiment, pulleys 76, 77 are provided at all of the connection parts 25, 26. That is, the main body side pulley 76a is provided at the main body side connection part 25a, the main body side pulley 76b is provided at the main body side connection part 25b, and the main body side pulley 76c is provided at the main body side connection part 25c.
Furthermore, the mounting section side connection portion 26a has a mounting section side pulley 77a, the mounting section side connection portion 26b has a mounting section side pulley 77b, and the mounting section side connection portion 26c has a mounting section side pulley 77c.

Pulleys 76 and 77 are straddling engagement members that straddle and engage linear member 73. Pulleys 76 and 77 are members that convert sliding friction into rolling friction to allow linear member 73 to move smoothly back and forth. In the present invention, the straddling engagement members are not limited to pulleys, and resin with a low coefficient of friction may be used. Also, simple hooks or eye bolts may be used as straddling engagement members.

In the multicopter 65 of this embodiment, a single linear member 73 connected in a ring shape is wound between all of the main body side connection parts 25a, 25b, 25c and the placement part side connection parts 26a, 26b, 26c.
Referring to Figure 14, the extension of linear member 73, which straddles main body side pulley 76a in an upward convex shape, engages and straddles base side pulley 77a in a downward convex shape, and then its further end engages and straddles main body side pulley 76b in an upward convex shape, and its further end engages and straddles base side pulley 77b in a downward convex shape, and its further end engages and straddles main body side pulley 76c in an upward convex shape, and its further end engages and straddles base side pulley 77c in a downward convex shape, and its further end engages and straddles main body side pulley 76a in an upward convex shape.

The multicopter 65 can be said to have one mounting side connection part 26 suspended from two main body side connection parts 25.

In the multicopter 65 of this embodiment, the length of the linear members 73 between the main body side connection parts 25a, 25b, 25c and the placement part side connection parts 26a, 26b, 26c can be changed.
For example, the distance between the main body side connection portion 25a and the placement portion side connection portion 26a can be increased, and the distance between the main body side connection portion 25c and the placement portion side connection portion 26c can be decreased.
In other words, in this embodiment, the line connecting the upper and lower connection parts 25, 26 is connected into a single line, so if the distance between the main body side connection part 25 and the mounting portion side connection part 26 at a particular position is increased, the distance between the main body side connection part 25 and the mounting portion side connection part 26 at any position will inevitably be shortened.

In the multicopter 65, when a portion of the linear member 73 becomes slack, the tension in that portion weakens and the other portions are pulled to eliminate the slack.
Therefore, in the multicopter 65, the length of the linear member 73 between the upper and lower connection parts 25, 26 of each part changes automatically to some extent due to the balance of the weight of the equipment mounting part 11 and the balance of the tension of the linear member 73, making it difficult for the linear member 73 to sag. In addition, the balance of the weight of the equipment mounting part 11 and the balance of the tension of the linear member 73 has the effect of keeping the attitude of the equipment mounting part 11 horizontal.
For example, as shown in FIG. 14B, when the annular support frame 10 of the main body 3 is inclined, the device mounting portion 11 suspended below is maintained in a substantially horizontal position.

The linear member 73 employed in the multicopter 65 is a single rope connected in a loop and has an endless structure, but a long rope with both ends may be used as the linear member and wound across multiple connection parts 25, 26. Also, a linear member wound across multiple connection parts 25, 26 and a linear member that simply connects the top and bottom may be mixed.

With reference to FIG. 15, yet another embodiment will be described.
In the multicopter 81 shown in Figure 15, the length of the linear member between the connection part on the main body side and the connection part on the mounting part side can be automatically changed during flight to stabilize the attitude of the equipment mounting part 11.
In the multicopter 81 of this embodiment, similarly to the above-described embodiments, the annular support frame 10 of the main body 3 has main body side connection parts 25a, 25b, and 25c. The equipment mounting part 11 also has mounting part side connection parts 26a, 26b, and 26c.
In the multicopter 81 of this embodiment, a winding device 83 is provided at one of the upper and lower connection parts 25, 26. In this embodiment, winding devices 83a, 83b, and 83c are provided at the main body side connection parts 25a, 25b, and 25c, respectively.

The winding device 83 used in this embodiment has a built-in constant torque member that exerts a constant torque. Specifically, the winding device 83 winds the linear member 16 with a constant torque using a spring such as that used in a tape measure.
In this embodiment, the winding devices 83a, 83b, 83c of the main body side connection parts 25a, 25b, 25c are connected to the mounting section side connection parts 26a, 26b, 26c by individual linear members 16. Specifically, the main body side connection part 25a and the mounting section side connection part 26a are connected by linear member 16a. Similarly, the main body side connection part 25b and the mounting section side connection part 26b are connected by linear member 16b. Furthermore, the main body side connection part 25c and the mounting section side connection part 26c are connected by linear member 16c.

In the multicopter 81 of this embodiment, if any of the linear members 16 sags, the linear member 16 is wound up by the winding device 83 to eliminate the slack. In the multicopter 81 of this embodiment as well, the length of the linear member 16 between the upper and lower connection parts 25, 26 of each part changes automatically to some extent depending on the weight balance of the equipment mounting part 11 and the balance of the tension of the linear member 16, which acts to keep the attitude of the equipment mounting part 11 horizontal.
For example, as shown in Figure 15 (b), when the annular support frame portion 10 of the main body portion 3 is in a horizontal position, the lengths of each linear member 16a, 16b, 16c are approximately equal, and the position of the equipment mounting portion 11 suspended below is horizontal.
On the other hand, even when the annular support frame 10 of the main body 3 is inclined as shown in FIG. 15C, the device mounting portion 11 suspended below maintains a substantially horizontal position.

The above describes a structure in which the length of the linear member 16 between the upper and lower connection parts 25, 26 of each part is changed depending on the weight balance of the equipment mounting part 11 and the balance of tension between the upper and lower connection parts 25, 26, but the length of the linear member 16 between the upper and lower connection parts 25, 26 may also be changed by electrical control.

In the multicopter 85 shown in FIG. 16, an electric winding device 86 is provided at one of the upper and lower connection parts 25, 26. The multicopter 85 also has a posture sensor (not shown) attached to the equipment mounting part 11, and in response to a signal from the posture sensor, each winding device operates to change the length of the linear member 16 between the upper and lower connection parts 25, 26 of each part, thereby maintaining the posture of the equipment mounting part 11 horizontal.

All of the multicopters described above have annular support frame sections 10, 32, but the equipment mounting section may be suspended by linear members from a branched frame such as the multicopter 100 in FIG. 17(a) or a radial frame such as the multicopter 200 in FIG. 17(b).

1, 5, 6, 35, 50, 60, 61, 62, 65, 80, 81, 85 Multicopter 2 Rotor 3 Main body 7 Storage battery (auxiliary equipment)
8 Control device Storage battery (auxiliary equipment)
10, 32 Support frame portion 11 Equipment mounting portion 12 Leg portion 16a, 16b, 16c Linear member 20 Motor 25a, 25b, 25c Main body side connection portion 26a, 26b, 26c Mounting portion side connection portion 40 Rope (Linear member)
41 Net (equipment mounting section)
42 Electrical equipment (auxiliary equipment)
51a, 51b, 51c, 51d, 52a, 52b Rotor 73 Linear member 76a, 76b, 76c Body side pulley 77a, 77b, 77c Placement side pulley

Claims (4)

A multicopter having a main body to which rotors are attached and an equipment mounting section to which auxiliary equipment is mounted,
the main body portion has a plurality of connection parts, the device mounting portion also has a plurality of connection parts, the connection parts on the main body side and the connection parts on the mounting portion side are connected by linear members, and the device mounting portion is suspended from the main body portion,
The length of the linear member between the connection part on the main body side and the connection part on the placement part side can be changed during flight ,
At least one of the connecting portion on the main body side and the connecting portion on the placement portion side is engaged with a linear member in a straddling state, and the linear member that engages with the connecting portion on one side engages with one of the connecting portions on the other side, and the same linear member further engages with another connecting portion on the one side,
A multicopter characterized in that the linear members are connected in a ring shape . The multicopter of claim 1 , wherein the connection portion includes a pulley, a hook, or an eyebolt. 3. The multicopter according to claim 1 , wherein the equipment mounting section is suspended from the main body section by a single linear member. The multicopter according to any one of claims 1 to 3 , characterized in that the main body portion has a ring-shaped support frame portion, and the connection portion is directly or indirectly attached to the support frame portion.

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