JP2021146824A - Thrust generator - Google Patents

Abstract

To provide a thrust generator capable of reducing impact of an external environment to a bolt, when the bolt is used on the thrust generator.SOLUTION: A thrust generator comprises: a rotary wing which can rotate around a prescribed axis; a hub which is provided on the prescribed axis, and supports the rotary wing; a first motor which is fixed to the hub by a fixing member, and rotates the hub around the prescribed axis; a second motor which is provided in the vicinity of the first motor and generates rotation motion for changing a pitch angle of the rotary wing; a first conversion part for converting the rotation motion of the second motor into linear motion; and a second conversion part for converting the linear motion obtained by conversion by the first conversion part into the rotation motion for changing the pitch angle. At least a part of the first conversion part is stored in the first motor, at least a part of the second conversion part is stored in the hub, the hub has a hollow part at an inside thereof, and a fixing member extends from the hollow part toward the first motor.SELECTED DRAWING: Figure 13

Description

The present invention relates to a thrust generator.

A multicopter is disclosed in Patent Document 1 as an example of an unmanned flight device. The multicopter of Patent Document 1 includes four rotors. Each rotor has a rotation axis extending in the vertical direction, and a plurality of rotary blades (blades) are provided in a direction (horizontal direction) perpendicular to the rotation axis. The multicopter flies by the lift generated by the rotor blades. The pitch angle of the rotor is variable. In Patent Document 1, the rotor blades are bolted to the rotor hub. Other parts and members that make up the multicopter are also bolted to predetermined parts.

Japanese Patent No. 6617259

Volts that attach members / parts deteriorate faster when exposed to dust or rain. Since the flight device has many rotating members / parts, it is dangerous if the rotating members / parts are separated from the predetermined positions due to damage of bolts or the like. Therefore, it is desirable to provide bolts for attaching members / parts so as not to be affected by the external environment as much as possible.
In view of the above problems, it is an object of the present invention to reduce the influence of the external environment on the bolt when the bolt is used in the thrust generator.

The thrust generator according to one aspect of the present invention is fixed to the hub by a rotary blade that can rotate around a predetermined shaft, a hub that is provided on the predetermined shaft and supports the rotary blade, and a fixing member. A first motor that rotates the hub around the predetermined axis, a second motor that is provided in the vicinity of the first motor and generates a rotary motion that changes the pitch angle of the rotary blade, and the first motor. A first conversion unit that converts the rotational motion of the two motors into a linear motion and a second conversion unit that converts the linear motion converted by the first conversion unit into a rotary motion that changes the pitch angle are provided. At least a part of the first conversion part is housed in the first motor, at least a part of the second conversion part is housed in the hub, the hub has a hollow part inside, and the fixing member is It extends from the hollow portion to the first motor.

When the first motor has a rotor and a stator, the rotor of the first motor may be fixed to the hub.
The first motor may be fixed to the hub via a spacer member for separating the hub and the first motor by a predetermined distance. In this case, the spacer member may have a hole through which the fixing member passes.
The spacer member may have a flange portion. In this case, the flange portion may be fixed to the first motor by the second fixing member.

According to the present invention, the fixing member for fixing the first motor to the hub extends from the hollow portion of the hub to the first motor, so that the fixing member is not easily affected by the external environment. Therefore, the safety of the thrust generator can be improved.

FIG. 1A is a perspective view showing a state in which a rotary blade is attached to the thrust generator according to the embodiment, and FIGS. 1B and 1C are attached to the thrust generator according to the embodiment. It is a side view which shows the state which changed the pitch angle of a rotary blade. FIG. 2 is a perspective view showing the configuration of the thrust generator of FIG. 1A when viewed from one end side of the rotating shaft in an exploded manner. FIG. 3 is a perspective view showing the configuration of the thrust generator shown in FIG. 1A when viewed from the other end side of the rotating shaft in an exploded manner. FIG. 4A is a perspective view showing the configuration of the thrust generator shown in FIG. 2 after assembly, and FIG. 4B is a perspective view showing the configuration of the thrust generator shown in FIG. 3 after assembly. 5 (a) is a plan view showing the configuration of the thrust generator according to the embodiment, and FIG. 5 (b) is a cross-sectional view cut along the line AA of FIG. 5 (a). 6 (a) is a plan view showing the configuration of the thrust generator according to the embodiment, and FIG. 6 (b) is a cross-sectional view cut along the line BB of FIG. 6 (a). 7 (a) is a plan view showing the configuration of a thrust generating motor of the thrust generator according to the embodiment, and FIG. 7 (b) is a cross-sectional view cut along the line CC of FIG. 7 (a). Is. 8 (a) is a perspective view showing the configurations of the pitch variable motor, the rotation transmission unit, and the rotation linear motion conversion unit of FIG. 6, and FIG. 8 (b) shows the rotation linear motion conversion unit of FIG. 8 (a). It is a perspective view which shows the structure which removed the support member which supports and the linear motion guide part. FIG. 9 is a plan view showing the configurations of the pitch variable motor, the rotation transmission unit, and the rotation linear motion conversion unit of FIG. 8A. 10 (a) is a cross-sectional view cut along the DD line of FIG. 9, and FIG. 10 (b) is a cross-sectional view cut along the EE line of FIG. 11 (a) is a perspective view showing the position of the linear moving body corresponding to the pitch angle of the rotary blade of FIG. 1 (b), and FIG. 11 (b) corresponds to the pitch angle of the rotary blade of FIG. 1 (c). It is a perspective view which shows the position of the linear moving body. FIG. 12 is a perspective view showing the configuration of the hub of FIG. 1 (b) in an exploded manner. FIG. 13 is a developed perspective view showing a rotor of a thrust generating motor, an extension, a hub case, and a hub mounting bolt. FIG. 14 is a view of the hub case as viewed from the axial direction of the thrust generating motor. FIG. 15 is a perspective view showing a modified example, and is the same perspective view as in FIG. 4 (b). FIG. 16 is a cross-sectional view of the modified example shown in FIG. 15, and shows the same cross section as in FIG. 5 (b). FIG. 17 is another cross-sectional view of the modified example shown in FIG. 15, and shows the same cross section as in FIG. 6 (b). FIG. 18 is a perspective view of the modified example shown in FIG. 15, and is a developed perspective view similar to FIG. FIG. 19 is a developed perspective view showing the extension of the modified example shown in FIG. 15, the hub case, and the hub mounting bolt.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the following embodiments do not limit the present invention, and not all combinations of features described in the embodiments are essential to the configuration of the present invention. The configuration of the embodiment may be appropriately modified or changed depending on the specifications of the apparatus to which the present invention is applied and various conditions (use conditions, use environment, etc.). The technical scope of the present invention is defined by the claims and is not limited by the following individual embodiments. In addition, the drawings used in the following description may differ from the actual structure in terms of scale and shape in order to make each configuration easy to understand.

In the following description, the case where the number of rotor blades driven by the thrust generator is three is taken as an example, but the number of rotor blades driven by the thrust generator is not necessarily limited to three, and N (N is Any positive integer) may be used.
FIG. 1A is a perspective view showing a state in which a rotary blade is attached to the thrust generator according to the embodiment, and FIGS. 1B and 1C are attached to the thrust generator according to the embodiment. Side views showing a state in which the pitch angle of the rotary blade is changed, FIGS. 2 and 3, are perspective views showing the configuration of the thrust generator of FIG. 1 (a) in an exploded manner, FIGS. 4 (a) and 4 (a). b) is a perspective view showing the configuration of the thrust generators of FIGS. 2 and 3 after assembly.

In FIGS. 1 (a), 1 (b) and 1 (c), the thrust generator 1 electrically drives the rotor blades H1 to H3. The rotary blades H1 to H3 are attached to the thrust generator 1 via the grips P1 to P3, respectively. The grips P1 to P3 support the rotor blades H1 to H3 so as to extend horizontally radially from the thrust generator 1. The thrust generator 1 is mounted on the projectile via the mounting surface 1A. The flying object to which the thrust generator 1 is mounted is, for example, a flyable airframe or a vehicle body such as a multicopter flying by a motor, an airplane, a rotorcraft, and an automobile having a flight function.

As shown in FIGS. 1 (a), 1 (b), 1 (c), 2, 2, 3, 4 (a) and 4 (b), the thrust generator 1 is a thrust generator motor. (1st motor) 2, pitch variable motor (2nd motor) 5, rotation transmission unit 6, rotation linear motion conversion unit (1st conversion unit) 7, linear motion rotation conversion unit (2nd conversion unit) 8, extension 9 and hub 10 are provided. The thrust generation motor 2 includes a stator 2A, a rotor 2B, and a frame 2C. Further, the rotor 2B includes a rotor shaft 4 and hollow portions 3A and 3B on the inner diameter side.

The thrust generation motor 2 generates the thrust F of the rotary blades H1 to H3. The stator 2A is composed of an electromagnetic steel plate and windings, and is located outside the rotor 2B. The stator 2A is fixed to the frame 2C. The mounting surface 1A of the thrust generating motor 2 can be provided on the frame 2C. The mounting surface 1A includes an opening 1B into which the rotation transmitting portion 6 can be inserted into the frame 2C. The support portion 1C extends radially inward from the outer frame of the frame 2C. The inner diameter portion of the frame 2C has a cylindrical shape, and the rotor shaft 4 is rotatably supported via the bearing U1. The frame 2C can be formed of an alloy such as duralumin.

A rotor shaft 4 is formed on the inner diameter side of the rotor 2B. The rotor shaft 4 is rotatably supported by the frame 2C via a bearing U1 and rotates about the axis of the rotation shaft S0. The hollow portions 3A and 3B are located in the thrust generating motor 2. Further, the hollow portion 3A is located between the rotor 2B and the rotor shaft 4 along the circumferential direction of the rotor 2B. The hollow portion 3B is located on the inner diameter side of the rotor shaft 4 along the axial direction of the rotor shaft 4.

The pitch variable motor 5 generates a rotary motion that changes the pitch angles θ1 to θ3 of the rotary blades H1 to H3. The pitch variable motor 5 is fixed to the frame 2C. At least a part of the pitch variable motor 5 is housed in the thrust generating motor 2. At this time, the pitch variable motor 5 can be located in the hollow portion 3A. The rotation shaft of the pitch variable motor 5 can be positioned in parallel with the rotation shaft S0 of the thrust generation motor 2.

The rotation transmission unit 6 transmits the rotational motion generated by the pitch variable motor 5 in the direction perpendicular to the rotation axis S0 of the thrust generation motor 2. That is, the rotation axis of the pitch variable motor 5 and the rotation axis S0 of the thrust generation motor 2 are parallel and different axes, and the rotational motion generated by the pitch variable motor 5 by the rotation transmission unit 6 is used for thrust generation. It is transmitted on the axis of the rotation axis S0 of the motor 2. The rotation transmission unit 6 is fixed to the frame 2C. At least a part of the rotation transmission unit 6 is housed in the thrust generating motor 2.

The rotation linear motion conversion unit 7 converts the rotational motion generated by the pitch variable motor 5 and transmitted via the rotation transmission unit 6 into a linear motion in the axial direction of the rotation axis S0. At least a part of the rotation linear motion conversion unit 7 is housed in the thrust generating motor 2. At this time, at least a part of the rotation linear motion conversion unit 7 can be located in the hollow portion 3B. In this case, at least a part of the rotation linear motion conversion unit 7 can be projected from the hollow portion 3B toward the rotary blades H1 to H3 along the axial direction of the rotation shaft S0. The rotation / linear motion conversion unit 7 is fixed to the frame 2C.

The linear motion rotation conversion unit 8 converts the linear motion converted by the rotation linear motion conversion unit 7 into rotational motion around the axes of the support shafts M1 to M3. The linear rotation conversion unit 8 is located outside the thrust generating motor 2.

The extension 9 is a spacer for maintaining a distance between the thrust generating motor 2 and the rotary blades H1 to H3 in the axial direction of the rotary shaft S0. The extension 9 prevents the rotor blades H1 to H3 from colliding with the thrust generating motor 2. The extension 9 is fixed to the end face of the rotor 2B.

The hub 10 accommodates the linear rotation conversion unit 8 and supports the grips P1 to P3 in a state where the grips P1 to P3 protrude from the hub 10. The hub 10 is fixed to the end face of the rotor 2B via the extension 9. That is, the hub 10 is supported by the frame 2C in a state where it can rotate about the axis of the rotation axis S0 via the rotor 2B. The hub 10 supports the rotary blades H1 to H3 in the direction perpendicular to the axial direction of the rotary shaft S0 via the grips P1 to P3.

When the thrust generation motor 2 operates, the rotor 2B rotates about the rotation shaft S0, so that the rotor blades H1 to H3 rotate. Then, the thrust F of the rotary blades H1 to H3 is generated with the rotation R1 to R3 of the rotary blades H1 to H3.

Here, the pitch variable motor 5, the rotation transmission unit 6, and the rotation linear motion conversion unit 7 are fixed to the frame 2C. Therefore, even if the rotor 2B rotates, the pitch variable motor 5, the rotation transmission unit 6, and the rotation linear motion conversion unit 7 do not rotate around the rotation axis S0.

Further, when the pitch variable motor 5 operates, the rotary blades H1 to H3 rotate around the axes of the support shafts M1 to M3, and the pitch angles θ1 to θ3 of the rotary blades H1 to H3 change. At this time, the rotational movement of the pitch variable motor 5 is transmitted to the rotation linear motion conversion unit 7 via the rotation transmission unit 6. Then, the rotary motion of the pitch variable motor 5 is converted into a linear motion in the axial direction of the rotary axis S0 by the rotary linear motion conversion unit 7. Then, the linear motion converted by the rotary linear motion conversion unit 7 is converted into three rotational motions around the axes of the support shafts M1 to M3 by the linear motion rotation conversion unit 8. Then, the rotational movement of the support shafts M1 to M3 is transmitted to the rotary blades H1 to H3 via the grips P1 to P3, respectively, and the pitch angles θ1 to θ3 of the rotary blades H1 to H3 are changed.

Here, the thrust generator 1 can change the thrust by making the pitch angles θ1 to θ3 of the rotary blades H1 to H3 variable. Further, the thrust generator 1 can improve the stability of the projectile by increasing the response speed of the thrust change by making the pitch angles θ1 to θ3 variable, and lengthens the blade length. It is possible to secure the thrust required for the flying object, and it is possible to suppress the increase in size and weight of the thrust generator 1. Further, since the thrust required in each situation can be generated at a low rotation speed of the thrust generation motor 2 as compared with the fixed pitch, noise depending on the rotation speed can be suppressed.

Further, the thrust generator 1 eliminates the need to use flood control by electrically changing the pitch angles θ1 to θ3 of the rotary blades H1 to H3. Therefore, it is not necessary to provide a complicated rotary seal mechanism for oil-sealing the hydraulic control unit for controlling the supply and discharge of oil and the rotating body, and it is possible to suppress the increase in size of the thrust generator 1. At the same time, the maintainability of the thrust generator 1 can be improved.

Further, by accommodating at least a part of the rotation linear motion conversion unit 7 in the thrust generation motor 2, the amount of protrusion of the rotation linear motion conversion unit 7 from the thrust generation motor 2 in the axial direction of the rotation axis S0 can be increased. Can be reduced. Therefore, even when the thrust generating motor 2 generates the thrust of the rotary blades H1 to H3 and the pitch variable motor 5 makes the pitch angles θ1 to θ3 of the rotary blades H1 to H3 variable, the axis of the rotating shaft S0 The thrust generator 1 can be made compact in the direction.

Further, by accommodating at least a part of the rotation linear motion conversion unit 7 in the hollow portion 3B, the thrust generation motor 2 does not become large in the axial direction of the rotation axis S0, and the rotation linear motion conversion unit 7 At least a part of the thrust can be accommodated in the thrust generating motor 2, and the thrust generating device 1 can be made compact in the axial direction of the rotating shaft S0.

Further, by transmitting the rotational motion generated by the pitch variable motor 5 via the rotation transmission unit 6, the rotary shaft S0 of the thrust generating motor 2 and the rotary shaft of the pitch variable motor 5 are arranged in parallel. This makes it possible to accommodate the pitch variable motor 5 in the thrust generating motor 2.

Further, by accommodating the linear motion rotation conversion unit 8 in the hub 10, the thrust generator 1 can be made compact in the axial direction of the rotation axis S0, and the linear motion rotation conversion unit 8 is exposed to the outside. It is possible to prevent this from happening.

Hereinafter, the configuration and operation of the rotation transmission unit 6, the rotation linear motion conversion unit 7, and the linear motion rotation conversion unit 8 will be described more specifically.
5 (a) and 6 (a) are plan views showing the configuration of the thrust generator according to the embodiment, and FIG. 5 (b) is a cross section cut along the line AA of FIG. 5 (a). FIG. 6 (b) is a cross-sectional view cut along the line BB of FIG. 6 (a), and FIG. 7 (a) shows a configuration of a thrust generating motor of the thrust generating device according to the embodiment. The plan view and FIG. 7 (b) are cross-sectional views taken along the line CC of FIG. 7 (a).

In FIGS. 7 (a) and 7 (b), the rotor 2B is supported by the frame 2C in a state of being rotatable around the axis of the rotating shaft S0 via the bearing U1. Further, in the thrust generating motor 2, a hollow portion 3A is provided between the rotor 2B and the rotor shaft 4, and a hollow portion 3B is provided in the rotor shaft 4.

Further, in FIGS. 2, 3, 5, 5 (a), 5 (b), 6 (a), and 6 (b), the rotation transmission unit 6 includes gears G1 to G3 and support members BJ1 to BJ3. Be prepared. The gears G1 to G3 transmit the rotational motion of the pitch variable motor 5 to the rotary linear motion conversion unit 7. The gear G1 is attached to one end of the ball screw shaft 7F. The gear G3 is attached to the rotating shaft of the pitch variable motor 5. The gear G2 is provided between the gear G1 and the gear G3 at a position where the gears G1 and G3 mesh with each other.

The frame 2C supports the gear G1 and the rotary linear motion conversion unit 7 in a state where the gear G1 and the ball screw shaft 7F can rotate via the support member BJ1. Further, the frame 2C supports the gear G3 and the rotation shaft of the pitch variable motor 5 in a rotatable state via the support member BJ3. Further, the frame 2C supports the gear G2 in a rotatable state via the support members BJ1 and BJ2. At this time, the gear G2 is arranged at a position where it meshes with the gears G1 and G3 while being sandwiched between the support members BJ1 and BJ2. The material of the gears G1 to G3 is, for example, carbon steel, and the material of the support members BJ1 to BJ3 is, for example, an aluminum alloy. A belt may be used instead of the gear as the mechanism of the rotation transmission unit.

A ball screw can be used as the rotation linear motion conversion mechanism of the rotation linear motion conversion unit 7. A sliding screw may be used as the rotation linear motion conversion mechanism of the rotation linear motion conversion unit 7. The rotation linear motion conversion unit 7 includes a linear motion transmission shaft 7D, a linear motion guide portion 7E, a ball screw shaft 7F, and a ball screw nut 7G.

The linear motion guide portion 7E guides the ball screw nut 7G and the linear motion transmission shaft 7D in a direction of linear motion along the rotation axis S0. At this time, the linear motion guide portion 7E regulates the rotational movement of the ball screw nut 7G with the rotation of the ball screw shaft 7F. The linear motion guide portion 7E has a shape protruding from the support member BJ1. The linear motion guide portion 7E can be provided integrally with the support member BJ1.

The ball screw shaft 7F is supported by the support member BJ1 in a rotatable state via the bearing U2. The ball screw shaft 7F rotates together with the gear G1 in a state of being screwed with the ball screw nut 7G via the rolling element, and causes the ball screw nut 7G to move linearly.

The ball screw nut 7G makes a linear motion along with the rotational motion of the ball screw shaft 7F, and transmits the linear motion to the linear motion transmission shaft 7D.

The linear motion transmission shaft 7D transmits the linear motion of the ball screw nut 7G to the linear motion rotation conversion unit 8. The linear motion transmission shaft 7D is fixed to the ball screw nut 7G, and the tip of the linear motion transmission shaft 7D is inserted into the inner ring of the bearing U3. The linear motion transmission shaft 7D has a shape that includes a part of the ball screw nut 7G and the ball screw shaft 7F.

A rack and pinion can be used as the linear rotation conversion mechanism of the linear rotation conversion unit 8. The linear motion rotation conversion unit 8 includes a linear motion element 11, racks A1 to A3, a case 21, support shafts M1 to M3, bearings E1 to E3, adapters D1 to D3, and pinions B1 to B3.

The linear motion body 11 is supported via a bearing U3 in a state of being rotatable around the linear motion transmission shaft 7D. At this time, the linear motion body 11 can move linearly along the axial direction of the rotation axis S0 together with the linear motion transmission shaft 7D.

The racks A1 to A3 are supported by the linear moving body 11. The racks A1 to A3 linearly move together with the linear moving body 11 in a state of being meshed with the pinions B1 to B3, respectively, and rotate the pinions B1 to B3, respectively.

Each of the support shafts M1 to M3 supports the grips P1 to P3 so as to project horizontally from the thrust generator 1. The support shafts M1 to M3 are held in the case 21 in a state of being rotatable around the axes of the support shafts M1 to M3 via bearings E1 to E3, respectively. The grip P1 and the support shaft M1 can be provided integrally, the grip P2 and the support shaft M2 can be provided integrally, and the grip P3 and the support shaft M3 can be provided integrally. The material of the grips P1 to P3 and the support shafts M1 to E3 is, for example, duralumin. In order to increase the durability of the grips P1 to P3 and the support shafts M1 to E3, for example, titanium may be used as the material of the grips P1 to P3 and the support shafts M1 to E3.

The pinions B1 to B3 are fixed to the support shafts M1 to M3, respectively. The pinions B1 to B3 rotate along with the linear motion of the racks A1 to A3, and the rotational motion is transmitted to the support shafts M1 to M3. The material of the pinions B1 to B3 and the racks A1 to A3 is, for example, chrome molybdenum steel.

The case 21 can be used as a part of the hub 10. The case 21 houses the linear moving body 11, racks A1 to A3, support shafts M1 to M3, bearings E1 to E3, adapters D1 to D3, and pinions B1 to B3. The case 21 is fixed to the end face of the rotor 2B via the extension 9. Further, the case 21 can support each of the support shafts M1 to M3 against the centrifugal force applied to the rotary blades H1 to H3 when rotating around the rotation shaft S0.

The adapters D1 to D3 are provided between the support shafts M1 to M3 and the bearings E1 to E3, and are supported by the support shafts M1 to M3, respectively. The inner peripheral surfaces of the adapters D1 to D3 are formed along the outer peripheral surfaces of the support shafts M1 to M3, and the outer peripheral surfaces of the adapters D1 to D3 are formed along the inner peripheral surfaces of the bearings E1 to E3. NS. As a result, the adapters D1 to D3 can support the support shafts M1 to M3 on the inner peripheral side of the bearings E1 to E3 while responding to the change in the diameter of the support shafts M1 to M3. The material of the case 21 and the adapters D1 to D3 is, for example, duralumin. For each of the bearings U3, E1 to E3, for example, a double row angular contact ball bearing can be used.

The extension 9 includes a flange 9A. The flange 9A can be provided integrally with the extension 9. The extension 9 can be attached to the end face of the rotor 2B via the flange 9A. Here, the extension 9 can be fixed to the rotor 2B by screwing the flange 9A to the rotor 2B with the bolt J6. The material of the extension 9 and the flange 9A is, for example, duralumin.

When the pitch variable motor 5 rotates, the gears G1 to G3 rotate along with the rotational movement of the pitch variable motor 5. Then, the ball screw shaft 7F rotates with the rotational movement of the gear G1, and the linear motion transmission shaft 7D moves linearly with the ball screw nut 7G with the rotational movement of the ball screw shaft 7F. At this time, the motion of the ball screw nut 7G and the linear motion transmission shaft 7D is guided by the linear motion guide unit 7E, and is limited to the linear motion along the axial direction of the rotation shaft S0 in the thrust generator 1.

The linear motion of the linear motion transmission shaft 7D is transmitted to the linear motion body 11, and the racks A1 to A3 move linearly together with the linear motion body 11 along with the linear motion of the linear motion transmission shaft 7D. At this time, the racks A1 to A3 linearly move in a state of being meshed with the pinions B1 to B3, respectively, and rotate the pinions B1 to B3. With the rotational movement of the pinions B1 to B3, the support shafts M1 to M3 rotate around their respective axes. Then, the rotational movement of the support shafts M1 to M3 is transmitted to the rotary blades H1 to H3 via the grips P1 to P3, respectively, and the pitch angles θ1 to θ3 of the rotary blades H1 to H3 are changed.

Here, by using the ball screw as the rotary linear motion conversion mechanism of the rotary linear motion conversion unit 7, the drive torque required for pitch variable can be reduced as compared with the case where the sliding screw is used, and for pitch variable use. The power saving of the motor 5 can be achieved.
Further, by using a rack and pinion as the linear rotation conversion mechanism of the linear rotation conversion unit 8, the longitudinal direction of each rack A1 to A3 can be aligned with the linear motion direction of the linear motion body 11, and each pinion can be aligned with the linear motion direction of the linear motion body 11. It is possible to align the circumferential directions of B1 to B3 with the circumferential directions of the support shafts M1 to M3. Therefore, the arrangement of the three rack and pinions can be compactly integrated, and even when the three rack and pinions are provided corresponding to the respective rotor blades H1 to H3, the size of the hub 10 can be suppressed while suppressing the increase in size. The linear rotation conversion unit 8 can be housed in the hub 10.

Hereinafter, the configuration and operation of the rotation transmission unit 6 and the rotation linear motion conversion unit 7 will be described in more detail.
8 (a) is a perspective view showing the configurations of the pitch variable motor, the rotation transmission unit, and the rotation linear motion conversion unit of FIG. 6, and FIG. 8 (b) shows the rotation linear motion conversion unit of FIG. 8 (a). A perspective view showing a configuration in which the supporting member and the linear motion guide portion are removed, and FIG. 9 is a plan view and a view showing the configurations of the pitch variable motor, the rotation transmission unit, and the rotation linear motion conversion unit in FIG. 8A. 10 (a) is a cross-sectional view cut along the line DD of FIG. 9, and FIG. 10 (b) is a cross-sectional view cut along the line EE of FIG.

In FIGS. 8 (a), 8 (b), 9, 10 (a) and 10 (b), the support member BJ1 can be fixed to the frame 2C by bolts J1. The bolts J1 can be arranged at the four corners of the support member BJ1, for example. The support member BJ2 is fixed to the support member BJ1 by the bolt J2 and the support column 31 in a state where the gear G2 is sandwiched between the support member BJ1 and the support member BJ1. The bolts J2 can be arranged at both ends of the support member BJ2, for example. Both shaft ends of the gear G2 are rotatably supported by the support members BJ1 and BJ2 via bearings. The support member BJ3 can be fixed to the frame 2C by bolts J3. The bolts J3 can be arranged at two places, for example, at the ends of the support member BJ3. Further, the support member BJ3 can fix the pitch variable motor 5 by the bolt J4.

The ball screw nut 7G includes a flange 7A. The flange 7A has a shape obtained by cutting a cylinder in two parallel planes, and a protruding portion of the flange 7A is arranged at an opening of the linear motion guide portion 7E. The flange 7A can be provided integrally with the ball screw nut 7G.
The linear motion transmission shaft 7D includes a flange 7B and a guide surface 7C. The guide surface 7C includes a sliding member 7H. The flange 7B and the guide surface 7C have a shape obtained by cutting out a cylinder in two parallel planes, and the flange 7B is arranged in the opening of the linear motion guide portion 7E.

The flat surface of the flange 7B and the guide surface 7C may be an integral flat surface. The flat surfaces may be two surfaces facing in opposite directions. A region into which the bolt J5 can be inserted can be provided in the protruding portion of the flanges 7A and 7B. By fixing the flange 7A to the flange 7B with the bolt J5 in the state where the flanges 7A and 7B are overlapped, the linear motion transmission shaft 7D can be fixed to the ball screw nut 7G.

Further, the flat surface or the guide surface 7C of the flange 7B may be provided with a recess into which the sliding member 7H can be inserted. Then, the sliding member 7H can be inserted into the recess and fixed to the flange 7B with an adhesive or the like. At this time, the sliding member 7H protrudes from the flat surface. The material of the sliding member 7H is, for example, a resin.

On the other hand, inside the linear motion guide portion 7E, a flat surface facing the flat surfaces of the flanges 7A and 7B and the guide surface 7C can be provided. Then, the sliding member 7H slides on the plane of the linear motion guide portion 7E along with the linear motion of the linear motion transmission shaft 7D, thereby limiting the motion of the linear motion transmission shaft 7D in the axial direction of the rotation axis S0. Can be done.

Here, a flat surface is provided on a part of the outer peripheral portion of the flanges 7A and 7B and the guide surface 7C, a protruding portion into which the bolt J5 can be inserted is provided on the flanges 7A and 7B, and the protruding portion is an opening of the linear motion guide portion 7E. The outer diameter of the linear motion guide portion 7E can be reduced by arranging the linear motion guide portion 7E, and the rotary linear motion conversion unit 7 can be moved to the rotor shaft while suppressing an increase in the diameter of the rotor shaft 4 in the thrust generating motor 2. It can be stored in 4.

Hereinafter, the configuration and operation of the linear motion rotation conversion unit 8 will be described in more detail.
11 (a) is a perspective view showing the position of the linear moving body corresponding to the pitch angle of the rotary blade of FIG. 1 (b), and FIG. 11 (b) corresponds to the pitch angle of the rotary blade of FIG. 1 (c). FIG. 12 is a perspective view showing the position of the linearly moving body, which is a perspective view showing the configuration of the hub of FIG. 1 (b) in an exploded manner.
In FIGS. 11 (a), 11 (b) and 12, the linear rotation conversion unit 8 sets the base 13, the lift guides T1 to T3 and the nuts S1 to S3 in order to limit the movement range in the linear motion direction. Be prepared. The base 13 includes an opening 14 that can pass through the tip of the linear motion transmission shaft 7D. The linear moving body 11 includes an opening 12, openings V1 to V3, and surfaces Z1 to Z3. The hub 10 includes a case 21, an outer lid 22, and an inner lid 23. The case 21 includes a housing portion 21A, hollow portions Q1 to Q3, openings 21B, and openings K1 to K3 (openings K3 are not shown). The inner lid 23 includes a through hole 23A.

The surfaces Z1 to Z3 are provided at positions where the linear moving body 11 is rotationally symmetric three times around the rotation axis S0. In the rotation symmetry of three times, the shape after rotation can be superimposed on the shape before rotation every time the linear moving body 11 is rotated by 120 ° around the axis of rotation axis S0. Each surface Z1 to Z3 can support racks A1 to A3, respectively. At this time, the surfaces Z1 to Z3 support the racks A1 to A3 at positions where the teeth of the racks A1 to A3 face the teeth of the pinions B1 to B3.
The bearing U3 is inserted into the opening 12, and the linear motion transmission shaft 7D is further inserted into the inner ring of the bearing U3. Lift guides T1 to T3 can be inserted into the openings V1 to V3, respectively.

The linear motion body 11 is supported by the outer ring of the bearing U3, and the tip of the linear motion transmission shaft 7D is fixed to the inner ring of the bearing U3 by the nut 15. The outer ring of the bearing U3 can be attached to the linear moving body 11 by, for example, a C-shaped retaining ring 16.

The base 13 supports the lift guides T1 to T3 in an upright position. The lift guides T1 to T3 can be provided integrally with the base 13. The planar shape of the base 13 can be made equal to the planar shape of the linear moving body 11. The positions of the openings V1 to V3 can correspond to the positions of the lift guides T1 to T3.

The opening 21B allows the linear moving body 11 to which the racks A1 to A3 are attached to be inserted into the accommodating portion 21A together with the base 13. Each of the openings K1 to K3 allows the support shafts M1 to M3 to be inserted into the case 21.

The accommodating portion 21A accommodates the linear moving body 11 to which the racks A1 to A3 are attached in the case 21 together with the base 13. The accommodating portion 21A is, for example, a hollow portion or a recess provided in the case 21. The planar shape of the accommodating portion 21A can correspond to the planar shape of the base 13. At this time, the planar shape of the accommodating portion 21A can be rotationally symmetric three times around the axis of the rotation axis S0.

On the other hand, the openings K1 to K3 into which the support shafts M1 to M3 can be inserted can be arranged along the outer circumferential surface of the accommodating portion 21A. At this time, the hollow portion Q1 into which the support shaft M1, the pinion B1, the bearing E1 and the adapter D1 can be inserted, the hollow portion Q2 into which the support shaft M2, the pinion B2, the bearing E2 and the adapter D2 can be inserted, and the support shaft M3 and the pinion. A hollow portion Q3 into which the B3, the bearing E3 and the adapter D3 can be inserted can be provided in the case 21. Support shafts M1 to M3, pinions B1 to B3, bearings E1 to E3, and adapters D1 to D3 can be inserted into the hollow portions Q1 to Q3, respectively, via openings 21B.

The tips of the lift guides T1 to T3 project to the outside of the inner lid 23 through the through holes 23A. Then, with the tips of the lift guides T1 to T3 protruding to the outside of the inner lid 23, the nuts S1 to S3 are attached to the tips of the lift guides T1 to T3, so that the base 13 is arranged in the accommodating portion 21A. can do.

The inner lid 23 is supported by the case 21. The inner lid 23 can be fixed to the case 21 with bolts J7. The outer lid 22 covers the inner lid 23. The outer lid 22 can be fixed to the inner lid 23. The material of the inner lid 23 is, for example, duralumin, and the material of the outer lid 22 is, for example, resin.

With the linear motion of the linear motion transmission shaft 7D, the racks A1 to A3 move linearly together with the linear motion body 11. At this time, the movement of the linear moving body 11 is guided by the lift guides T1 to T3, and the moving range of the linear moving body 11 in the linear motion direction is limited by the base 13 and the nuts S1 to S3. The pinions B1 to B3 rotate along with the linear motion of the racks A1 to A3, and the support shafts M1 to M3 rotate around their respective axes with the rotary motion of the pinions B1 to B3. Then, the rotary blades H1 to H3 rotate with the rotational movement of the support shafts M1 to M3, and the pitch angles θ1 to θ3 of the rotary blades H1 to H3 are changed. For example, when the linear moving body 11 is at the position shown in FIG. 11A, the pitch angles θ1 to θ3 of the rotary blades H1 to H3 are set as shown in FIG. When it is in the position b), the pitch angles θ1 to θ3 of the rotary blades H1 to H3 are set as shown in FIG. 1 (c).

Here, by providing the surfaces Z1 to Z3 at positions that are rotationally symmetric three times around the axis of the rotation axis S0 and arranging the racks A1 to A3 on the surfaces Z1 to Z3, one linear motion body 11 is provided. By making the linear motion, it is possible to generate three rotational motions around the axes of the three support shafts M1 to M3. Therefore, the pitches of the three rotary blades H1 to H3 can be made variable while allowing the linear motion rotation conversion unit 8 to be housed in the hub 10.

In the above embodiment, the rotor blades H1 to H3 are arranged directly under the thrust generator 1, and the thrust generator 1 is mounted on the lower part of the body of the projectile, but the rotor blades H1 to H3 generate thrust. It is arranged directly above the device 1, and the thrust generator 1 may be mounted on the upper part of the body of the projectile.

FIG. 13 shows the rotor 2B of the thrust generating motor 2, the extension 9, the case 21 of the hub 10, and the hub mounting bolt J10 among the parts shown in FIG. In FIG. 13, the outer lid 22 and the inner lid 23 are removed from the case 21. Although there are actually three bolts J10, only one is shown in FIG. FIG. 14 is a view of the case 21 as viewed from below in the axial direction of the thrust generating motor 2. An opening 21G through which the linear motion transmission shaft 7D (FIG. 5B) passes is formed in the bottom portion 21E of the accommodating portion 21A of the case 21.

As shown in FIG. 14, three holes 21F for passing the bolt J10 are formed in the bottom portion 21E of the accommodating portion 21A of the case 21. As can be seen from FIGS. 13 and 14, the three holes 21F are holes corresponding to the three holes 9D formed on the lower end surface 9C of the extension 9. The three holes 9D are formed at equal intervals in the circumferential direction of the extension 9 (that is, they are formed at intervals of 120 degrees in the circumferential direction). The three holes 9D are through holes. The case 21 is thrust through the extension 9 by passing the three bolts J10 through the three holes 21F and the three holes 9D and screwing them into the three female screw holes 2B2 formed in the end face 2B1 of the rotor 2B. It is fixed to the generation motor 2 (more specifically, the rotor 2B).

As shown in FIG. 13, three pin holes 9F are formed between the three holes 9D on the lower end surface 9C of the extension 9. The pin hole 9F is not a through hole but a hole having a predetermined depth. A positioning pin J11 (FIG. 19) is inserted into the pin hole 9F. The positioning pin J11 inserted into the pin hole 9F projects by a predetermined height from the lower end surface 9C of the extension 9. The protruding portion of the positioning pin J11 fits into a hole (not shown) formed in the case 21. By this fitting, the extension 9 is positioned with respect to the case 21.

The accommodating portion 21A of the case 21 is a hollow space (hollow portion) formed inside the case 21, and the bolt J10 extends from the accommodating portion 21A to the thrust generating motor 2. As can be seen from FIGS. 13 and 5 (b), the case 21 (hub 10) is fixed to the thrust generating motor 2 by the bolt J10. It can also be expressed that the thrust generating motor 2 is fixed to the hub 10 by the bolt J10.

The flange 9A of the extension 9 is formed with six holes 9A1 through which the bolt J6 (FIG. 5) passes. The six holes 9A1 are formed at equal intervals in the circumferential direction of the flange 9A. The bolt J6 passes through the hole 9A1 and is screwed into the hole 2B4 formed in the second end surface 2B3 of the rotor 2B. In this embodiment, the extension 9 is fixed to the rotor 2B by bolts J6 and J10. The bolt J10 fixes the main body of the extension 9 to the rotor 2B, and the bolt J6 fixes the flange 9A of the extension 9 to the rotor 2B. Since the extension 9 is fixed to the rotor 2B by the bolts J6 and J10, the fixing of the extension 9 can be strengthened.
The head of the bolt J10 is located inside the case 21. That is, the bolt J10 that fixes the hub 10 is not located on the outer surface of the thrust generator 1 (it is not exposed to the outside). Therefore, it is unlikely that the bolt J10 will be exposed to dust, rain, or the like. Therefore, the influence of the external environment on the bolt J10 can be reduced.

<Modification example>
In the above embodiment, the extension 9 has the flange 9A, but the extension 9 does not have to have the flange 9A. That is, when a large load does not act on the extension 9, fixing between the extension 9 and the rotor 2B may be simplified from the above-described embodiment by omitting the flange 9A. The configuration in which the extension does not have the flange 9A will be described with reference to FIGS. 15 to 19. In FIGS. 15 to 19, the same parts and configurations as those in the above-described embodiment are designated by the same reference numerals. In this modification, reference numeral 109 is attached to the extension.
FIG. 15 is a diagram corresponding to FIG. 4 (b). FIG. 16 is a diagram corresponding to FIG. 5 (b). FIG. 17 is a diagram corresponding to FIG. 6 (b). FIG. 18 is a diagram corresponding to FIG. FIG. 19 shows an extension 109, a case 21 of a hub 10, a hub mounting bolt J10, and a positioning pin J11. The extension 109 has a substantially cylindrical shape. The positional relationship between the extension 109 and the hub case 21 in FIG. 19 is upside down from the positional relationship between the extension 109 and the hub case 21 in FIG.

As shown in FIGS. 16 to 19, in this modification, the extension 109 is fixed to the rotor 2B by the bolt J10. In this modification, since the extension 109 does not have the flange 9A, the shape of the extension 109 can be simplified. Therefore, the manufacturing process of the extension 109 can be simplified. Further, since the flange 9A is not provided, the bolt J6 for fixing the flange 9A to the rotor 2B becomes unnecessary.
Also in this modification, the hub 10 is fixed to the rotor 2B by the bolt J10 inside the case 21. Therefore, it is unlikely that the bolt J10 will be exposed to dust, rain, or the like. Therefore, the influence of the external environment on the bolt J10 can be reduced.

In the above-described embodiment and modification, the extensions 9 and 109 are provided between the rotor 2B and the hub 10, but the extensions 9 and 109 may not be provided. For example, depending on the shape and size of the rotor blades H1 to H3 (or depending on the shape of the end faces 2B1 and 2B3 of the rotor 2B and the shape of the case 21), the rotor blades H1 to H3 have thrust even without the extensions 9 and 109. It may not come into contact with or collide with the generation motor 2. In such a case, the extensions 9 and 109 may be omitted. Even if the extensions 9 and 109 are omitted, the configuration in which the bolt J10 for fixing the hub 10 to the rotor 2B is located inside the case 21 does not change.

1 ... Thrust generator, H1 to H3 ... Rotating blades, P1 to P3 ... Grip, 2 ... Thrust generating motor, 2A ... Stator, 2B ... Rotor, 2C ... Frame, 3A, 3B ... Hollow part, 4 ... Rotor shaft, 5 ... Pitch variable motor, 6 ... Rotation transmission unit, 7 ... Rotational linear motion conversion unit, 8 ... Linear rotation conversion unit, 9 ... Extension, 109 ... Extension

Claims (4)

A rotor blade that can rotate around a predetermined axis,
A hub provided on the predetermined shaft and supporting the rotor blade,
A first motor that is fixed to the hub by a fixing member and rotates the hub around the predetermined axis.
A second motor provided in the vicinity of the first motor and generating a rotational motion that changes the pitch angle of the rotary blades,
The first conversion unit that converts the rotational motion of the second motor into linear motion, and
It is provided with a second conversion unit that converts the linear motion converted by the first conversion unit into a rotary motion that changes the pitch angle.
At least a part of the first conversion unit is housed in the first motor, and at least a part of the second conversion part is housed in the hub.
A thrust generator characterized in that the hub has a hollow portion inside, and the fixing member extends from the hollow portion to the first motor. The thrust generator according to claim 1, wherein the first motor has a rotor and a stator, and the rotor of the first motor is fixed to the hub. The first motor is fixed to the hub via a spacer member for separating the hub and the first motor by a predetermined distance, and the spacer member has a hole through which the fixing member passes. Item 3. The thrust generator according to item 1 or 2. The thrust generator according to claim 3, wherein the spacer member has a flange portion, and the flange portion is fixed to the first motor by a second fixing member.

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