JPH09175495A - Tail rotor for hilicopter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the safety of the tail rotor. SOLUTION: A plurality of blade bodies 4 are disposed in the inner side of a frame body 6 while one end of each blade body is fixed to the frame body 6. The outer circumferential part of the frame body is inserted into a recessed groove 14 formed in the inner circumference of a support member 12 so as to be rotatably supported by rollers 15 and 16. A teeth part 604 is formed on the side surface of a wide width part 602 for the frame body 6, a gear 18 to be meshed with the teeth part 604 is disposed in a place for an opening 12A formed at the specified position of the support member 12 in such a way that the gear can be rotated while a rotating shaft 28 is made as a pivot, and the rotating shaft 28 is connected with an engine. When the rotating shaft 28 is rotated with the engine rotated, its rotation is transmitted to the frame body 6 via the gear 18, and the frame body 6 is rotated together with the blade bodies 4, so that air flows are thereby developed, which prevents a hilicopter from being rotated as the main rotor of the hilicopter is rotated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helicopter tail rotor.

[0002]

2. Description of the Related Art A single-rotor helicopter rotates a main rotor to levitate the airframe, and at the same time, rotates a tail rotor provided at the tail of the airframe, in a direction substantially orthogonal to the airflow generated by the main rotor. It generates an air flow and prevents the machine body from rotating due to a reaction caused by the rotation of the main rotor.

Such a tail rotor has a structure in which blades are radially attached to a rotary shaft, and the rotary shaft is rotated by an engine of a helicopter to generate the airflow.

[0004]

However, a strong force is usually applied to the blades of the tail rotor as air is driven, and the force concentrates on the rotary shaft portion, so that a large force is applied to the rotary shaft portion. Bending and torsion moments act. Therefore, the root of the blade and the rotating shaft may be broken due to brittle fatigue, and careful design is required including selection of constituent materials. And it is necessary to carry out regular inspections at these locations with relatively high frequency.

Further, if a part of the blade body is damaged, the center of gravity of the tail rotor is eccentric and the balance is lost. However, the influence concentrates on the central rotating shaft and its bearings, and therefore these parts are extremely damaged. There is a possibility that a large amount of force will be applied, leading to total destruction. Then, the objective of this invention is providing the tail rotor of a helicopter which improves the safety of a helicopter significantly.

[0006]

In order to achieve the above-mentioned object, the present invention provides a tail rotor of a helicopter, wherein a plurality of blade bodies and a plurality of blade bodies are arranged in a virtual circle in the circumferential direction of the virtual circle. An annular frame body that connects the outer peripheral portions of the respective blade bodies in a state where they extend substantially radially from the center of the virtual circle and rotates integrally with each blade body, and the outer peripheral portion of the frame body is the frame body. And a power transmission means for transmitting the power of a driving means mounted on the helicopter to the frame body to rotate the frame body.

The present invention is also characterized in that the supporting means includes an annular supporting member arranged along the outer peripheral portion of the frame body. According to the present invention, an open concave groove is continuously formed inward in the radial direction on the inner peripheral portion of the support member, and the outer peripheral portion of the frame is movably supported by the concave groove. It is characterized by being.

According to the present invention, a plurality of rollers, which contact the frame body and restrict movement of the frame body in the width direction of the groove body, are provided inside the groove body, and a plurality of rollers contact the frame body to form a recess. A plurality of rollers for restricting the movement of the frame body in the depth direction of the groove are provided, and the frame body is supported by the rollers so as to be movable in the circumferential direction. According to the present invention, the supporting means forms a predetermined gap between the first magnets arranged along the circumferential direction on the outer peripheral portion of the frame body, and the supporting means is provided. A second magnet that is arranged along the circumferential direction on the inner peripheral portion of the member and that exerts a repulsive force between the first magnet and the first magnet; and the frame body includes the first and second magnets. It is characterized in that it is supported by a magnet so as to be movable in the circumferential direction.

The present invention is also characterized in that the power transmission means includes a gear, and teeth are formed on the outer peripheral portion of the frame body in the circumferential direction so as to mesh with the gear.

In the present invention, when the power of the driving means mounted on the helicopter is transmitted to the frame body by the power transmitting means, the frame body supported by the supporting means so as to be movable in the circumferential direction together with the plurality of blade bodies. It spins and, as a result, an air flow is generated to prevent rotation of the airframe associated with the rotation of the main rotor of the helicopter.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described. FIG. 1 is a sectional plan view showing an example of a tail rotor of a helicopter according to the present invention, and FIG. 2 is a front view thereof. The tail rotor 2 of the helicopter is composed of a plurality of blade bodies 4, a frame body 6 that connects the plurality of blade bodies 4, a support means 8 that supports the outer peripheral portion of the frame body 6, and the like. The blade body 4 is
For example, it is formed of an aluminum alloy or the like. The blade bodies 4 are arranged in the virtual circle at intervals in the circumferential direction of the virtual circle so as to extend substantially radially from the center of the virtual circle, and the outer ends of the blade bodies 4 are arranged on the frame body 6. It is connected. Therefore, by rotating the frame body 6, the plurality of blade bodies 4 rotate together with the frame body 6.

The frame 6 has an annular plate shape, a wide portion 602 is formed on the outer peripheral portion, and a tooth portion 604 is formed on one side surface of the wide portion 602. The supporting means 8 is provided with an annular supporting member 12 extending along the outer circumference of the virtual circle, and the inner peripheral portion of the supporting member 12 is continuously provided with an open concave groove 14 in the circumferential direction. Has been formed. Inside the groove 14, there are a roller 15 having a support shaft extending in the width direction of the groove 14 and a roller 16 having a support shaft extending in the depth direction of the groove 14.
4 are provided at intervals in the circumferential direction. Frame 6
Is inserted into the groove 14, and the roller 15 contacts the inner surface of the wide portion 602 to restrict the movement of the frame body 6 in the depth direction of the groove 14, and the roller 16 prevents the roller body 6 from moving. The movement of the frame body 6 in the width direction of the recessed groove 14 is restricted by contacting both side surfaces of the frame body 6, whereby the frame body 6 is centered on the center of the support member 12, in other words, the center of the plurality of blade bodies 4. It is rotatably supported as a center.

Further, an opening 12A formed by removing the inner wall of the groove 14 is provided at a predetermined position of the support member 12, and the outer peripheral portion of the frame 6 is exposed through this opening 12A. ing. A gear 18 and a rotary shaft 28, which are power transmission means according to the present invention, are disposed at the opening 12A of the support member 12. The rotating shaft 28 extends in the radial direction of the frame body 6 and is rotatably supported by a bearing (not shown). The gear 18 is fixed to one end of the rotary shaft 28 and is engaged with the tooth portion 604.

The annular support member 12 is attached to the tail portion 30 of the helicopter so that both end surfaces thereof are vertical. The other end of the rotary shaft 28 is connected to the engine mounted on the helicopter.

In such a structure, when the above engine of the helicopter is started and the main rotor of the helicopter rotates, the rotating shaft 28 also rotates at a speed corresponding to the rotation speed of the main rotor. As a result, the frame body 6 is driven via the gear 18 and the tooth portion 604, the frame body 6 rotates together with the blade body 4, and is orthogonal to the direction of arrow A (FIG. 1), that is, the airflow generated by the main rotor. An airflow is generated in a predetermined direction. As a result, the rotation of the body of the helicopter due to the rotation of the main rotor is blocked, and the helicopter can fly.

In the tail rotor 2 of this helicopter, the blade body 4 is not attached to the rotating shaft at the central portion like the tail rotor of a conventional helicopter, but is arranged inside the frame body 6 to form the frame body 6. Since it is a structure that is installed in a distributed manner, there is no large bending and torsion moment concentrated on the rotating shaft, unlike in the past.
It is possible to solve the conventional problem of fracture due to brittle fatigue of the base of the blade and the rotating shaft. Therefore, it is reliable and safe.

Further, if a part of the blade body 4 is damaged, the center of gravity of the frame body 6 and the blade body 4 are eccentric and the balance is lost. Therefore, there is a very low risk that the tail rotor 2 as a whole will be damaged due to damage of a part of the blade body 4.

Further, when the blade body is attached to the central rotating shaft and the outer peripheral portion of the blade body is not particularly protected as in the prior art, obstacles and the like easily enter the rotating region of the tail rotor. Although there is a risk of causing a serious accident due to breakage of the tail rotor, in this tail rotor 2, the outer peripheral portion of the blade body 4 is inevitably protected by the frame body 6 and the support member 12, so that safety is also in this respect. It is highly likely.

In the above embodiment, the rotation of the rotating shaft 28 is transmitted to the frame 6 by the gear 18, but as shown in FIG. 3, the pulley 32 is rotated by the rotating shaft 28, and the rotation is caused by the belt 34. It can also be transmitted to the frame body 6.

In the above-described embodiment, the frame 6 is rotatably supported by the rollers 15 and 16 with respect to the support member 12. Instead of using rollers, a bearing is provided between the frame 6 and the support member 12. It is also possible to interpose and rotatably support the frame body 6. Further, a magnet is mounted on the outer peripheral portion of the frame body 6, while a magnet is also mounted in the recessed groove 14 of the support member 12 with a gap kept between the magnet and the repulsive force acting between these magnets. , The frame 6 to the concave groove 14 of the support member 12.
It is also possible to hold it in the interior without contact. With such a configuration, there is no loss due to friction, so that efficiency can be increased, and noise and vibration can be significantly suppressed. Further, it is possible to eliminate a failure due to wear or the like.

Further, in order to prepare for damage to the tail rotor,
It is also effective to equip, for example, two tail rotors having basically the same structure as the tail rotor 2 shown in FIG. 1 as shown in FIGS. 4 and 5. In the case of FIG. 4, the tail rotor 36
Along with the small tail rotor 38 the tail 3 of the helicopter
They are arranged side by side with 0. These tail rotors 3
Frame bodies 40, 4 for connecting the blade bodies 43, 44 of 6, 38
Tooth portions are formed on the outer peripheral portion of 2, and the tail rotors 36 and 38 are arranged in a state where they are meshed with each other. The rotation of the rotary shaft 28 is transmitted to the frame body 40 of the tail rotor 36 by the same mechanism as that of the tail rotor 2 shown in FIG. On the other hand, in the tail rotor 38, the rotation of the frame body 40 of the tail rotor 36 is transmitted to the frame body 40, and the frame body 40 rotates together with the blade body 44. With such a configuration, even if one tail rotor is damaged, the air flow can be generated by the other tail rotor, so that safety can be enhanced.
Although the blades 43 and 44 rotate in opposite directions in FIG. 4, the tail rotors 36 and 38 can be rotated in opposite directions by changing the inclination angles of the blades 43 and 44 with respect to the frames 40 and 42. The airflow can be generated in the same direction even when rotated to.

Further, FIG. 5A is a schematic side view,
In the case shown in the schematic perspective view in FIG. 3B, two tail rotors 46 and 48 of the same size are arranged in an overlapping manner, and each tail rotor 46 and 48 is basically the same as the tail rotor 2 of FIG. It is driven by the rotary shaft 28 by the same mechanism as above to generate an air flow. However, tooth portions are formed on opposite side surfaces of both frame bodies 6, and the gear 18 fixed to the rotary shaft 28 is simultaneously engaged with the tooth portions of each frame body. Also in this case, even if one tail rotor is damaged, the other tail rotor can generate an airflow, so that safety can be improved. Also in this case, the rotation directions of both the frame bodies 6 are opposite to each other as in the case of FIG. 4, but the same direction is obtained by making the inclination angles of the blade bodies 4 of each frame body 6 opposite to each other. An air flow is generated in.

[0023]

As described above, in the tail rotor of the helicopter according to the present invention, when the power of the drive means mounted on the helicopter is transmitted to the frame body by the power transmission means, it can be moved in the circumferential direction by the support means. The supported frame rotates with the plurality of blades, and as a result, an airflow is generated to prevent the rotation of the airframe accompanying the rotation of the main rotor of the helicopter.

Therefore, in the tail rotor of this helicopter, the blade body is not attached to the rotating shaft of the central portion unlike the tail rotor of the conventional helicopter, but is arranged inside the frame body and dispersed and attached to the frame body. Because of the structure, unlike the conventional case, large bending and torsion moments do not concentrate on the rotary shaft portion, and the problem of fracture due to brittle fatigue of the base of the blade and the rotary shaft can be solved. Therefore, it is reliable and safe.

Further, if a part of the blade body is damaged, the center of gravity of the frame body and the blade body are eccentric and the balance is lost, but the influence is concentrated on the central rotating shaft and its bearing as in the conventional case. Therefore, there is a low risk that the tail rotor as a whole will be damaged due to a part of the blade body being damaged.

Further, when the blade body is attached to the central rotating shaft and the outer peripheral portion of the blade body is not particularly protected as in the prior art, obstacles and the like easily enter the rotating region of the tail rotor. Although there is a risk of causing a serious accident due to breakage of the tail rotor, in this tail rotor, the outer peripheral portion of the blade body is inevitably protected by the frame body and the supporting member, and therefore the safety is also high in this respect.

[Brief description of the drawings]

FIG. 1 is a sectional plan view showing an example of a tail rotor of a helicopter according to the present invention.

2 is a side view showing a tail rotor of the helicopter of FIG. 1. FIG.

FIG. 3 is a front view showing a modification of the tail rotor of the helicopter according to the present invention.

FIG. 4 is a front view showing another modification of the tail rotor of the helicopter according to the present invention.

5A is a schematic front view showing still another modification of the tail rotor of the helicopter according to the present invention, and FIG. 5B is a schematic perspective view of the same.

[Explanation of symbols]

 2, 36, 38, 46, 48 Tail rotor 4, 43, 44 Blade body 6, 40, 42 Frame body 8 Support means 12 Support member 12A Opening 14 Recessed groove 15, 16 Roller 18 Gear wheel 28 Rotating shaft 30 Tail portion

Claims (6)

[Claims] 1. In a tail rotor of a helicopter, a plurality of blade bodies, and a state in which the plurality of blade bodies are extended substantially radially from the center of the virtual circle at intervals in the circumferential direction of the virtual circle within the virtual circle. And an annular frame body that connects the outer peripheral portions of the respective blade bodies and integrally rotates with each blade body, and a support means that supports the outer peripheral portion of the frame body so as to be movable in the circumferential direction of the frame body, A tail rotor for a helicopter, comprising: a power transmission unit that transmits the power of a driving unit mounted on the helicopter to the frame body to rotate the frame body. 2. The tail rotor of a helicopter according to claim 1, wherein the supporting means includes an annular supporting member arranged along an outer peripheral portion of the frame body. 3. An open concave groove is continuously formed inward in a radial direction on an inner peripheral portion of the support member, and an outer peripheral portion of the frame is movably supported by the concave groove. A tail rotor for a helicopter according to claim 2. 4. Inside the concave groove, a plurality of rollers that contact the frame body to restrict movement of the frame body in the width direction of the concave groove, and a depth of the concave groove that contacts the frame body. The tail rotor of a helicopter according to claim 3, further comprising a plurality of rollers for restricting the movement of the frame body in the vertical direction, and the frame body being supported by the rollers so as to be movable in the circumferential direction. 5. The supporting means forms a predetermined gap between a first magnet arranged circumferentially on an outer peripheral portion of the frame body and the first magnet to form the supporting means. A second magnet that is arranged along the circumferential direction on the inner peripheral portion of the member and that exerts a repulsive force between the first magnet and the first magnet; and the frame body includes the first and second magnets. The tail rotor for a helicopter according to claim 2, wherein the tail rotor is supported by a magnet so as to be movable in the circumferential direction. 6. The tail rotor for a helicopter according to claim 1, wherein the power transmission means includes a gear, and teeth are arranged on an outer peripheral portion of the frame body in a circumferential direction and mesh with the gear.