JP2019188988A - Unmanned flight body having improved quietness - Google Patents

Abstract

To provide an unmanned flight body having improved quietness.SOLUTION: An unmanned flight body 1 has: a housing 2 which is configured from a bottom plate member, a ceiling member, and a wall member which connects the vicinity of the bottom plate member and the vicinity of the ceiling member; plural arm parts 8 which extends outward from the housing 2; and a motor 10 which is located at an end part at a free end side of the arm part 8 and rotates a propeller 12. The unmanned flight body 1 has an intermediate member which is located between the motor 10 and an end part 8a of the arm part, and reflects and/or absorbs oscillation due to rotation of the motor 10. The arm part 8 is formed from a material with prescribed oscillation damping performance, and a principal surface of at least one of the bottom plate member and the ceiling member is divided into plural portions, thereby improving quietness.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an unmanned air vehicle with improved silence.

  Conventionally, the use of a small unmanned air vehicle (also called “drone”) has been proposed. A technique for spraying agricultural chemicals or the like using such a drone has been proposed (for example, Patent Document 1).

JP 2017-24488 A

  A drone obtains thrust for flight by rotating a plurality of propellers with a motor. Fly with controlled speed and direction by the rotation of the motor. However, vibration is generated by the rotation of the motor and the change in the flying state of the drone, resulting in noise.

  The present invention is an attempt to solve such a problem, and an object thereof is to provide an unmanned air vehicle with improved quietness.

  According to a first aspect of the present invention, there is provided a casing composed of a bottom plate member, a ceiling member, and a wall member connecting the vicinity of the periphery of the bottom plate member and the vicinity of the periphery of the ceiling member; An unmanned aerial vehicle having a plurality of extending arm portions and a motor for rotating a propeller disposed at an end portion on a free end side of the arm portion, the unmanned flying body between the motor and the end portion And an intermediate member that reflects and / or absorbs vibration caused by rotation of the motor, the arm portion is formed of a material having a predetermined vibration damping capability, and the bottom plate member and the ceiling member At least one of the principal surfaces is an unmanned aerial vehicle that is divided into a plurality of portions and has improved quietness.

  According to the configuration of the first invention, the vibration caused by the rotation of the motor can be reflected and / or absorbed by the intermediate member, and the vibration can be attenuated by the arm portion. Furthermore, since at least one main surface of the bottom plate member and the ceiling member is divided into a plurality of portions, the main surface does not vibrate greatly as a whole. Thereby, silence can be improved.

  According to a second invention, in the configuration of the first invention, the intermediate member is formed of a vibration-proof material and / or a vibration-damping material, and the vibration-proof material is natural rubber or silicone rubber, The damping material is an unmanned aerial vehicle with improved quietness, which is butyl rubber or polynorbornene rubber.

  A third invention is an unmanned aerial vehicle with improved quietness, wherein the material having the predetermined vibration damping capacity is magnesium or a magnesium alloy in the configuration of the first invention or the second invention.

  According to the present invention, it is possible to provide an unmanned aerial vehicle with improved quietness.

It is a schematic perspective view which shows the unmanned air vehicle which concerns on embodiment of this invention. It is the elements on larger scale which show a housing | casing etc. It is an enlarged view which shows the ceiling member etc. of a housing | casing. It is an expansion perspective view which shows a baseplate member etc. It is an enlarged plan view which shows a baseplate member etc. It is the schematic which shows a motor. It is the schematic which shows the connection structure of a motor and an arm. It is the schematic which shows the connection structure of the motor and arm of 2nd embodiment.

  Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail. In the following description, the same reference numerals are given to the same components, and the description thereof is omitted or simplified. Note that description of configurations that can be appropriately implemented by those skilled in the art will be omitted, and only the basic configuration of the present invention will be described.

<First embodiment>
As shown in FIG. 1, the unmanned aerial vehicle 1 (hereinafter referred to as “unmanned aircraft 1”) of the present embodiment includes a housing 2, and an upper cover 4 (hereinafter referred to as “canopy 4”) on the housing 2. ") Is arranged. The drone 1 is an example of an unmanned air vehicle, and the housing 2 is an example of a housing. As will be described below, the drone 1 has a plurality of types of vibration preventing means and vibration attenuating means, thereby reducing noise during flight due to vibrations with different causes and modes and improving quietness.

  A positioning device that uses positioning radio waves from a navigation satellite such as a computer, an autonomous flight device, a motor drive circuit, a wireless communication device, and a GPS (Global Positioning System) that controls each part of the drone 1 is provided inside the housing 2. Electronic parts such as a calculation unit, an inertia sensor, and an atmospheric pressure sensor are arranged.

  As shown in FIG. 2, the housing 2 includes a bottom plate member 22, a ceiling member 24, and a plurality of wall members 30 that connect the bottom plate member 22 and the vicinity of the periphery of the ceiling member 24. The bottom plate member 22 and the ceiling member 24 have substantially the same outer shape, and are substantially hexagonal. As shown in FIGS. 2 and 3, a battery 200 and an antenna 202 of a positioning device using GPS are arranged on the ceiling member 24 of the housing 2. As shown in FIG. 2, the battery 200 and the antenna 202 are covered with the canopy 4.

  As shown in FIG. 1, an arm root portion 6 is connected to the housing 2, and a round bar-shaped arm 8 is connected to each arm root portion 6 in an aspect extending outward from the housing 2. The arm 8 is an example of an arm part. A motor 10 is connected to the end 8 a on the free end side of each arm 8, and a propeller 12 is connected to each motor 10. A leg portion 14 is disposed in the vicinity of the distal end portion of each arm 8. The canopy 4 is made of resin. The bottom plate member 22, the ceiling member 24, and the leg portion 14 are made of, for example, carbon fiber reinforced plastic, and are configured to be lightweight while maintaining strength.

  The arm 8 is made of a material having a predetermined vibration damping capability. The material having a predetermined vibration damping capability is, for example, magnesium or a magnesium alloy. The predetermined vibration damping ability is, for example, the vibration damping ability of magnesium or a magnesium alloy. Since the arm 8 is formed of a material having a predetermined vibration damping capability, vibration caused by rotation of the motor 10 and vibration caused by fluctuations in the flight state of the drone 1 can be attenuated.

  As shown in FIGS. 4 and 5, a plurality of wall members 30 are arranged in a point-symmetric manner around the central hole C <b> 1 located at the center on the peripheral edge of the bottom plate member 22. The wall member 30 is disposed between the plurality of arm root portions 6 in a state where the wall member 30 is in contact with the plurality of arm root portions 6. A space S <b> 1 is formed by the bottom plate member 22, the wall member 30, and the arm root portion 6. In the state of FIG. 4, the ceiling member 24 is connected to the plurality of wall members 30 and the root portion 6 to form the housing 2.

  A grid-like protrusion 22a is formed on the inner main surface of the bottom plate member 22, and the main surface is divided into a plurality of portions. Similarly, lattice-like protrusions (not shown) are also formed on the main surface inside the ceiling member 24, and the main surface is divided into a plurality of portions. This prevents the main surface of the bottom plate member 22 and the main surface of the ceiling member 24 from vibrating as a whole.

  As shown in FIG. 6, the motor 10 is an outer rotor type brushless DC (Direct current) motor. FIG. 6A shows the appearance of the motor 10, and FIG. 6B shows an outline of the inside of the motor 10. As shown in FIG. 6B, a plurality of winding portions 10ab are radially fixed to the central portion 10aa of the stator 10a. A plurality of permanent magnets 10bd are fixed to the inner peripheral surface of the rotor 10b. Adjacent permanent magnets 10bd have different polarities. By controlling the current flowing through each winding portion 10ab, a rotating magnetic field is generated, and the winding portion 10ab and the permanent magnet 10bd are repeatedly attracted and repelled, whereby the rotor 10b rotates.

  As shown in FIG. 6A, the rotor 10b has a notch 10bc, and the winding 10ab of the stator 10a is cooled by air. The rotor 10b is formed with a connecting portion 10ba, and the propeller 12 is connected to the connecting portion 10ba.

  As shown in FIG. 7, the motor 10 is connected to the end portion 8 a of the arm 8 via an intermediate member 13 formed of a vibration-proof material or a vibration-damping material. The anti-vibration material is, for example, natural rubber or silicone rubber. The damping material is, for example, butyl rubber or polynorbornene rubber. The stator 10a, the intermediate member 13 and the end portion 8a of the motor 10 are formed with a plurality of through holes penetrating the respective members. The bolts 11a are passed through the through holes, and the bolts 11a are fixed with the nuts 11b. As a result, the motor 10 is fixed to the end 8a.

  As described above, since the motor 10 is connected to the end 8 a via the intermediate member 13, vibration caused by the rotation of the motor 10 is reflected or absorbed by the intermediate member 13. Furthermore, depending on the intermediate member 13, the vibration caused by the rotation of the motor 10 cannot be attenuated, and the vibration due to the speed change, the direction change, and the attitude change of the drone 1 has a predetermined vibration attenuation capability. Vibration is damped by the arm 8 made of material. Further, even when the arm 8 cannot completely attenuate the vibration, the main surface of the bottom plate member 22 and the ceiling member 24 is formed with a lattice-like protrusion 22a and the like, and is divided into a plurality of portions. Therefore, the main surface is prevented from vibrating as a whole, and noise is reduced.

<Second Embodiment>
A second embodiment will be described with reference to FIG. Descriptions common to the first embodiment are omitted, and only matters different from the first embodiment are described.

  The intermediate member 13A of the second embodiment is formed by combining a vibration-proof material 13a and a vibration-damping material 13b. The vibration energy generated by the rotation of the motor 10 can be reflected by the vibration isolating material 13a, and the vibration energy generated by the rotation of the motor 10 can be absorbed by the vibration damping material 13b.

  Note that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within a scope in which the object of the present invention can be achieved are included in the present invention.

DESCRIPTION OF SYMBOLS 1 Unmanned air vehicle 2 Case 4 Upper cover 6 Arm root part 8 Arm 10 Motor 12 Propeller 13, 13A Intermediate member 14 Leg part 22 Bottom plate member 22a Grid-like protrusion 24 Ceiling member 30 Wall member C1 Center hole part

Claims (3)

A casing composed of a bottom plate member, a ceiling member, and a wall member connecting the vicinity of the peripheral portion of the bottom plate member and the vicinity of the peripheral portion of the ceiling member;
A plurality of arms extending outward from the housing;
An unmanned aerial vehicle having a motor for rotating a propeller, which is disposed at an end portion on a free end side of the arm portion,
An intermediate member disposed between the motor and the end, for reflecting and / or absorbing vibration caused by rotation of the motor;
The arm portion is formed of a material having a predetermined vibration damping capability,
At least one main surface of the bottom plate member and the ceiling member is divided into a plurality of portions.
An unmanned air vehicle with improved quietness. The intermediate member is formed of a vibration-proof material and / or a vibration-damping material,
The vibration-proof material is natural rubber or silicone rubber,
The damping material is butyl rubber or polynorbornene rubber,
The unmanned aerial vehicle with improved quietness according to claim 1. The material having the predetermined vibration damping ability is magnesium or a magnesium alloy.
The unmanned aerial vehicle with improved quietness according to claim 1 or 2.