JPH07236774A - Model plane - Google Patents

Abstract

PURPOSE:To provide a model plane that eliminates a frictional resistance loss and prevents the body and propeller from being damaged at the flight. CONSTITUTION:The model plane is composed of a propeller 2 which generates a driving force, a rubber string 3, attached at the both ends of a rotational axis 2A of the propeller 2, which holds the rubber string 3 as well as is a driving source of rotation, and a main body frame 4 which supports the rubber string 3. The main body frame 4 may be made of an elastic material so that it becomes the driving source of the rotation of the propeller 2 together with the elasticity of the rubber string 3. If the main body frame 4 is made of an elastic material, a non-elastic string may be substituted for the rubber string 3. A first rubber string 53 which holds a propeller 52 may be connected to a second rubber string 61 via a relay 57. This lengthen the effective length of the rubber string to increase a number of turns, resulting that a longer flight time is realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a model airplane which is driven by a propeller rotating to obtain propulsive force.

[0002]

2. Description of the Related Art Generally, a model airplane has a propeller as a means for obtaining a propulsive force, and this propeller is rotatably attached to the front of a body by a bearing. A rubber cord is stretched between the propeller and the rear part of the machine body, and the propeller is rotated by twisting the elastic rubber cord.

[0003]

However, each of the conventional examples described above has the following problems.

(1) A bearing is used to rotate the propeller, but this bearing has frictional resistance. This frictional resistance was not small compared to the rotational force due to the twisting of the rubber cord, so that the energy loss was large.

(2) Since the propeller rotates in front of the model airplane, the propeller may come into contact with something during the flight of the model airplane, and the propeller or the propeller may be damaged.

(3) In the case of a model airplane, the fuselage, main wings,
The fuselage such as the tail is exposed, and when it falls or collides with something, the aircraft directly contacts, and this aircraft is likely to be damaged.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a model airplane that does not suffer a loss due to frictional resistance and is free from the risk of damage to propellers and airframes.

[0008]

In order to solve the above problems, a first invention is to provide a propeller that obtains a propulsive force, and a propeller that is attached to both sides of a rotating shaft of the propeller and that holds the propeller and that serves as a drive source for rotation. It is characterized in that it is composed of an elastic cord and a main body frame supporting the elastic cord.

A second invention is a propeller for obtaining a propulsive force,
It is composed of a string attached to both sides of the rotation shaft of the propeller and holding the propeller, and a main body frame which is made of an elastic member, supports the string, and serves as a drive source for the rotation of the propeller due to the flexure caused by the twist of the string. It is characterized by being done.

A third invention is a propeller for obtaining a propulsion force,
The elastic cords, which are attached to both sides of the rotation shaft of the propeller and hold the propeller, and which are made up of elastic members, support the elastic cord, and the elastic deformation of the elastic cord contributes to the elasticity of the elastic cord. It is characterized in that it is composed of a main body frame which is a drive source of rotation of the propeller.

A fourth invention is a propeller for obtaining a propulsion force,
One end is attached to each side of the rotating shaft of the propeller to hold the propeller and to serve as a drive source for rotation, and the other end of each first rubber string is rotatably supported. A relay portion that transmits a rotational force in one or a plurality of directions, a body frame that supports each relay portion, and a first rubber cord that is provided so as to extend between the body frame and the relay portion. And a second rubber cord serving as a drive source for rotation of the propeller.

A fifth invention is a propeller for obtaining propulsion force,
One end is attached to each side of the rotating shaft of the propeller to hold the propeller and to serve as a drive source for rotation, and the other end of each first rubber string is rotatably supported. A plurality of relay portions that transmit the rotational force in one or a plurality of directions, a main body frame that supports each relay portion, and a plurality of relay portions are continuously bridged between the relay portions and the final stage is connected to the main body frame. It is characterized in that it is composed of a plurality of rubber cords that act as a drive source for rotation of the propeller together with the first rubber cord.

According to a sixth aspect of the present invention, in the fourth or fifth aspect of the invention, the relay portion is fitted around the first bevel gear engaged with the first rubber cord, and is fitted around the first bevel gear to rotate the same. And one or a plurality of second bevel gears for transmitting.

A seventh invention is characterized in that, in the first to sixth inventions, the main body frame is provided with a wing for suppressing rotation of the main body frame by the propeller to maintain flight stability.

An eighth invention is characterized in that, in the first to seventh inventions, the main body frame is constituted by a rod member surrounding the periphery of the propeller.

[0016]

In the first aspect of the present invention, since the propeller is held by the rubber cord supported by the main body frame, there is no frictional portion when the propeller rotates, and no loss due to frictional resistance occurs. Thereby, the propeller can be efficiently rotated.

In the second aspect of the invention, when the cord holding the propeller is supported by the body frame and the cord is twisted, the body frame having elasticity is bent accordingly. Then, the propeller is rotated by the repulsive force due to the elasticity of the main body frame.

According to the third aspect of the invention, when the rubber cord holding the propeller is supported by the main body frame and the rubber cord is twisted, the main body frame is bent accordingly. Then, the propeller is rotated by the repulsive force due to the elasticity of both the main body frame and the rubber cord.

In the fourth aspect of the invention, each of the first rubber cords is twisted with each of the relay portions while holding the propeller, and the second rubber cord is also twisted through the relay portions. As a result, the first elastic cord and the second elastic cord work together as a driving source for the rotation of the propeller, and the propeller can be rotated at a higher speed for a long time.

In the fifth aspect of the invention, the propeller is rotated by the first rubber cord and the plurality of rubber cords continuously connected to the first rubber cord. As a result, the number of windings of the rubber cord can be further increased, and the propeller can be rotated for a longer time.

In the sixth invention, the first rubber cord is locked to the first bevel gear, and the second bevel gear fitted to the first bevel gear is locked to the second rubber cord, whereby the first rubber cord is locked. When twisted, the rotational force due to the twist is transmitted to the second elastic cord via each bevel gear, and the first elastic cord and the second elastic cord are configured as a substantially continuous elastic cord, and the number of windings of the elastic cord is significantly increased. Can be increased.

According to the seventh aspect of the invention, since the main body frame is provided with the wing, rotation of the main body frame is suppressed by this wing, and stability during flight is secured.

In the eighth aspect of the invention, since the main body frame is constituted by the rod member surrounding the propeller, the strength of the model airplane is improved. For this reason, if the model airplane collides with something when the model airplane is in flight and twists such as rubber bands are reduced and falls, the propeller is surrounded by the main frame and the main frame itself is also strong. Since the propeller does not come into contact with something to be damaged, it does not get damaged even if the body frame collides with something.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a model airplane according to the present invention will be described below with reference to the drawings.

[First Embodiment] FIG. 1 is a perspective view showing a model airplane 1 of this embodiment, and FIG. 2 is a plan view of the model airplane 1 of FIG.

Reference numeral 2 in the figure is a propeller. This propeller 2 is for obtaining the propulsive force of the model airplane 1 by rotating in one direction (left rotation direction in FIG. 2),
It is arranged in the vertical direction and propels the model airplane 1 in the vertical direction. At the center of the propeller 2, there is provided a rotating shaft 2A extending vertically from that portion. This rotating shaft 2A
One end of a rubber cord 3 serving as a drive source for rotation is attached to each of the. Each rubber cord 3 is arranged in the vertical direction,
Holds the propeller 2 vertically. The other end of each rubber cord 3 is supported by the body frame 4.

The main body frame 4 is composed of two elliptical rings 4A formed in an elliptical shape and a circular ring 4B supporting each elliptical ring 4A. A material having high rigidity is used for the elliptical ring 4A and the circular ring 4B. The elliptical rings 4A are arranged vertically and are connected to each other in a state where their planar shapes are orthogonal to each other as shown in FIG. As a result, an ellipsoidal (oval) space is formed by the two elliptical rings 4A, and the propeller 2 and each rubber cord 3 are arranged inside the space. Each oval ring 4
A is reinforced at its intermediate position by a circular ring 4B. This prevents the body frame 4 from being deformed or damaged even if it is dropped during flight.

Two blades 5 are attached to the joints between the elliptical ring 4A and the circular ring 4B at positions facing each other. The wings 5 are provided to prevent the main body frame 4 from rotating in the opposite direction of the propeller 2 in accordance with the rotation of the propeller 2 and maintain stability during flight. 4 is attached so as to be inclined or spirally formed in a direction in which the rotation of 4 is suppressed. Alternatively, by setting the inclination or spiral of the wings 5 small, the main body frame 4 may be gently rotated to maintain stability during flight.

In the model airplane 1 configured as described above, when each rubber cord 3 is twisted and released in the air, each rubber cord 3 is
The propeller 2 held by rotates to push air downward, and the model airplane 1 is lifted upward. At this time,
Rotation of the main body frame 4 by the propeller 2 is suppressed by the wings 5. That is, when the surrounding air is pushed downward by the propeller 2, the downward air flow is generated by the two blades 5.
The rotation of the main body frame 4 is suppressed by hitting. In addition,
The rotation of the body frame 4 depends on the degree of inclination of the blades 5, etc.
There are cases where it is completely suppressed and cases where it is suppressed to loose rotation.

When the rubber string 3 is less twisted during the flight of the model airplane 1 and the rotation speed of the propeller 2 is lowered, the model airplane 1 loses its propulsive force and falls. At this time, in the model airplane 1, the body frame 4 of the model airplane 1 comes into contact with the object and the ground, and the propeller 2 inside does not come into contact with the model frame 1.

As described above, since the propeller 2 is held by the two rubber cords 3 without using a bearing, it is not necessary to use a conventional bearing, and energy loss due to frictional resistance can be eliminated. . As a result, the propeller 2 can be efficiently rotated.

Since the propeller 2 is housed in the main body frame 4, when the model aircraft 1 hits or drops something, the propeller 2 does not come into direct contact with anything, and the propeller is rotating. It is possible to solve problems such as damage caused by the contact of the two.

Further, when the model airplane 1 hits something, only the main body frame 4 is in direct contact with it, and the main body frame 4 having sufficient strength surely prevents the model airplane 1 from being damaged. can do.

[Second Embodiment] FIG. 3 is a perspective view showing a model airplane 11 of this embodiment, FIG. 4 is a plan view of the model airplane shown in FIG. 3, and FIG. 5 is a schematic view showing a state of use.

Reference numeral 12 in the drawing denotes a propeller, which has the same structure as the propeller 2 of the first embodiment. One end of a rubber cord 13 is attached to the rotating shaft 12A of the propeller 12 to hold the propeller 12. The other end of each rubber cord 13 is supported by the body frame 14. The main body frame 14 is composed of two circular rings 14A in which rod-shaped elastic members are formed in an annular shape. The two circular rings 14A are joined in a state of being orthogonal to each other. As a result, a spherical space is formed by the two circular rings 14A, and the propeller 12 and each rubber cord 1 are provided inside the space.
3 are provided. The two circular rings 14A are connected to each other at their intersecting portions, and the other end of each rubber cord 13 is connected to this connecting portion. When the rubber cord 13 is twisted, the two circular rings 14A are largely bent as shown in FIG. 5, so that the number of turns due to the twist of the rubber cord 13 can be increased. As a result, the elastic rubber cord 13 and the main body frame 14 act on each other to serve as a drive source for rotating the propeller 12.

Four blades 15 are attached to an intermediate position in the vertical direction of each circular ring 14A. The blade 15 has the same structure as the blade 5 of the first embodiment.

When flying the model airplane 11 having the above structure, the rubber cord 13 is twisted. As a result, as shown in FIG.
The two circular rings 14A also largely bend, and the number of windings of the rubber cord 13 is large. When the model airplane 11 is released in the air in this state, the propellers 12 held by the respective rubber cords 13
, But is rotated by the repulsive force due to the twist of the rubber cord 13 and the bending of the circular ring 14A. Then, the model airplane 11 flies by the same operation as in the first embodiment.

As described above, the propeller 12 is held by the two rubber cords 13 without using a bearing, and the propeller 12 is rotated by the repulsive force due to the twist of the rubber cord 13 and the bending of the circular ring 14A. The same operation and effect as the first embodiment can be obtained, and the propeller 1
2 can be rotated at a higher speed for a long time.

In this embodiment, the elastic rubber cord 13 is used, but a non-elastic cord may be used. In this case, the elastic force of the circular ring 14A can provide the same operation and effect as the first embodiment.

[Third Embodiment] FIG. 6 is a perspective view showing a model airplane 21 according to the third embodiment, and FIG. 7 is a model airplane 2 of FIG.
It is a top view of 1.

In this embodiment, two propellers 22 and 23 are used.
Is used. Each of the propellers 22 and 23 has substantially the same structure as the propeller 2 of the first embodiment. Propeller 22
Is set to obtain an upward propulsive force by rotating to the left in the plane state shown in FIG. The propeller 23 is set so as to obtain a propulsive force in the upward direction by rotating in the right direction, which is the reverse of the propeller 22. These propellers 22 and 23 are arranged in parallel and rotate in opposite directions to prevent the model airplane 21 from rotating. Therefore, the blades 5 and 15 used in the first and second embodiments are unnecessary.

Rotating shafts 22A, 2 of the propellers 22, 23
One end of each of the rubber strings 24 and 25 is attached to the 3A to hold the propeller 12. Each rubber strap 24,
The other end of 25 is supported by the body frame 26. The main body frame 26 includes two circular rings 28 formed in an annular shape having a size that covers the propellers 22 and 23, and an elliptical ring 29 that is joined to the circular rings 28 and covers the entire two propellers 22 and 23. It consists of and. A material having high rigidity is used for each of the circular ring 28 and the elliptical ring 29. As a result, the main body frame 2
6 forms an elliptical space that encloses the propellers 22 and 23 that are juxtaposed in the horizontal direction, and the other ends of the rubber cords 24 and 25 are attached to the joints of the circular rings 28 and the elliptical ring 29. It is connected.

When flying the model airplane 21 having the above-described structure, the rubber cords 24 and 25 are twisted in opposite directions. In this state, when the model airplane 21 is released in the air, each rubber cord 2
The propellers 22 and 23 held on the rubber cords 4 and 25 are
The repulsive forces against the twists of 4 and 25 cause reverse rotation.
As a result, while the rotation of the model airplane 21 is suppressed, the surrounding air is pushed downward by the propellers 22 and 23, and the model airplane 21 flies by the same operation as in the first embodiment.

From the above, the same operation as in the first embodiment,
Along with being able to exert an effect, two propellers 2
2, 23, it becomes possible to obtain a stronger propulsive force while suppressing the rotation of the model airplane 21.

In this embodiment, a material having a high rigidity is used for the main body frame 26, but a rod-shaped elastic member may be used. As a result, the rotation speed and rotation duration of the propellers 22 and 23 can be extended by the same operation as in the second embodiment. When a rod-shaped elastic member is used as the body frame 26, a string having no elasticity may be used instead of the rubber strings 24 and 25.

[Fourth Embodiment] FIG. 8 is a perspective view showing a model airplane 31 according to the present embodiment.

In the figure, 32 is a propeller, and this propeller 3
2 is composed of three blades like the propeller 2 of the first embodiment, but a protective wheel 32A is provided around it. A rubber cord 33 is attached to the rotary shaft 32B of the propeller 32.
One end of each is attached. Each rubber cord 33
The other end of is supported by the body frame 34. The main body frame 34 is composed of a semicircular ring 34A formed by bending a rod-shaped elastic member into a semicircular shape.
The other end of each rubber cord 33 is connected to each end of the semicircular ring 34A.

A blade 35 is provided at an intermediate position of the semicircular ring 34A.
Is attached. This wing 35 has the same structure as the wing 5 of the first embodiment, and is attached so as to be inclined so that the main body frame 34 does not rotate.

When flying the model airplane 31 having the above-mentioned structure, the rubber cord 33 is twisted. This allows the semicircular ring 34A
Bends, and the number of turns of the rubber cord 33 is increased. In this state,
Release the model airplane 31 in the air. As a result, each rubber string 3
The propeller 32 held by 3 rotates by the repulsive force against the elasticity of the rubber cord 33 and the semicircular ring 34A, and the model airplane 31 flies. In particular, this model airplane 31 is suitable for aerial hovering.

As described above, the same effect as the first embodiment can be obtained.

Although the elastic cord 33 having elasticity is used in this embodiment, a string having no elasticity may be used instead of the rubber cord 33.

When the elastic rubber cord 33 is used, a material having high rigidity may be used for the main body frame 34.

[Fifth Embodiment] FIG. 9 is a perspective view showing a model airplane 41 of this embodiment, and FIG. 10 is a model airplane 4 shown in FIG.
It is a principal part exploded perspective view of 1.

In the figure, 42 is a propeller, and this propeller 4
2 has the same structure as the propeller 2 of the first embodiment. One end of a rubber cord 43 is attached to the rotary shaft 42A of the propeller 42. The other end of each rubber cord 43 is supported by the body frame 44. The main body frame 44 includes four frame pieces 45 made of a rod-shaped elastic material.
And a frame receiving member 46 that rotatably supports both ends of each frame piece 45. At both ends of the frame piece 45, shaft holes 45A for pivotally supporting the frame piece 45 on the frame receiving fitting 46 are provided. The frame receiving member 46 has a configuration in which four support pieces 46A are arranged at 90 ° intervals. Each support piece 46A has a longitudinal groove 46B that allows the frame piece 45 to swing in the vertical direction with the end of each frame piece 45 pivotally supported.

Then, both ends of the four frame pieces 45 are respectively inserted into the respective support pieces 46A of the frame receiving metal fittings 46 arranged above and below, and the shaft holes 45A of the frame pieces 45 and the support pieces 46A penetrate. Support shaft 4 through hole 48
By attaching 7, the main body frame 44 having an ellipsoidal shape as a whole is formed.

A blade 49 is attached to an intermediate position of the frame piece 45. The blade 49 is the blade 4 of the first embodiment.
The main body frame 44 is attached so as to be inclined so as not to rotate.

When flying the model airplane 41 having the above structure, the rubber cord 43 is twisted. Accordingly, both ends of the four frame pieces 45 are supported by the support shaft 4 with respect to the frame receiving fitting 46.
7, the frame piece 45 is largely bent as in the case of FIG. 5 described above. As a result, the number of turns due to the twist of the rubber cord 43 can be increased. In this state, the model airplane 41 is released in the air. As a result, the propeller 1 is repelled by the repulsive force due to the twist of the rubber cord 43 and the bending of the frame piece 45.
2 rotates, and the model airplane 11 flies by the same operation as in the first embodiment.

As described above, the same effect as the second embodiment can be obtained.

Although the elastic rubber cord 43 is used in this embodiment, the same effect as described above can be obtained by using the elastic cord.

[Sixth Embodiment] FIG. 11 is a front view showing a model airplane 51 according to this embodiment, FIG. 12 is a plan view of the model airplane 51 of FIG. 11, and FIG. 13 is a perspective view showing a relay section 57. .

Reference numeral 52 in the drawing denotes a propeller, which has the same structure as the propeller 2 of the first embodiment. One end of the first rubber cord 53 is attached to the rotary shaft 52A of the propeller 52 to hold the propeller 52. Each first rubber cord 5
The other end of 3 is supported on the body frame 54 side.

The main body frame 54 includes three elliptical rings 54A formed in an elliptical shape and each elliptical ring 54A.
And a circular ring 54B that supports the. The overall structure of these is almost the same as that of the first embodiment. Three
The two oval rings 54A are connected to each other at intervals of 60 degrees. A material having high rigidity is used for the body frame 54.

A blade 55 is attached to each elliptical ring 54A. The blade 55 is formed in a flat plate shape and extends downward from an intermediate position of the elliptical ring 54A.
It also functions as a leg of the model airplane 51.

Relays 57 for directly supporting the other end of the first rubber cord 53 are provided at the upper and lower ends of the body frame 54, respectively. This relay unit 57 is
It transmits the rotational force from the first rubber cord 53 in two directions, and mainly comprises a frame 58 and three bevel gears 59 as shown in FIG. Three bevel gears 5
9 are arranged side by side, and in this state the frame 5
It is supported by 8. The central bevel gear 59 is connected to the first elastic cord 53. Two second rubber strings 61 are connected to the bevel gears 59 on both sides, respectively. The second rubber cord 61 has one end connected to the bevel gears 59 on both sides and the other end connected to the body frame 54. As a result, as a rubber cord for rotating the propeller 52, the first portion with the relay portion 57 sandwiched is provided.
The elastic cord 53 and the second elastic cord 61 are used. As a result, the number of turns can be significantly increased. Furthermore, the first
While one rubber cord 53 is provided, two second rubber cords 61 are provided to increase the driving force for rotating the propeller 52.

When flying the model airplane 51 having the above structure, the rubber cords 53 and 61 are twisted. This ensures a sufficient number of turns. In this state, when the model airplane 11 is released into the air, the propellers 52 held by the respective first rubber cords 53
However, the first elastic cord 53 and the second elastic cord 61 rotate by the repulsive force against the twist. Then, the model airplane 51 flies by the same operation as in the first embodiment.

As described above, since the first rubber cord 53 and the second rubber cord 61 are connected by the relay portion 57 to greatly increase the number of turns, the same effect as the first embodiment can be obtained. At the same time, the propeller 52 can be rotated at a higher speed for a long time.

In this embodiment, the relay portion 57 transmits the rotational force from the first elastic cord 53 to the two second elastic cords 61 arranged in two directions. Alternatively, the second rubber cord 61 may be provided to transmit the rotational force. By arranging the second rubber cords 61 in three or more directions, a stronger torque can be obtained.

Further, in the present embodiment, the first rubber cord 53 and the second rubber cord 61 are connected in two stages by one relay portion 57, but they may be connected in three stages or more. As a result, the effective length of the rubber cord is increased and the number of turns can be further increased, so that the flight time of the model airplane 51 can be further extended.

Further, although the wings 55 are formed in a flat plate shape in this embodiment, they may be formed to be inclined in order to suppress the rotation of the model airplane 51 as in the first embodiment.

[Modification] Although the blade 5 is set small in the first embodiment, it may be formed as shown in FIGS. 14 to 16. Here, the wing 63 is shaped like a bird wing and is largely curved in a spiral shape.

Further, as shown in FIGS. 17 and 18, a propeller 64 having a protection wheel 64A is used, and the propeller 64 is formed by a body frame 6 composed of one circular ring 65A.
5 may be attached. This body frame 6
Two wings 66 are attached below 5. The wing 66 is composed of a main leg portion 66A and an auxiliary leg portion 66B, has a cross shape in a plan view, and contacts the ground at three points. This wing 66
Are attached to both sides of the body frame 65 to support the entire model airplane 67, and the model airplane 67 stands on the ground.

With this, the same operation and effect as those of the first embodiment can be obtained.

[0073]

As described above in detail, according to the model airplane of the present invention, the following effects can be obtained.

(1) Since the propeller is held from both sides by a rubber cord and the bearing is not used, loss due to frictional resistance can be eliminated.

(2) Since the main body frame is made of an elastic member and, together with the bending of the main body frame, is used as the drive source for the rotation of the propeller, the propeller can be rotated at a higher speed for a long time. .

(3) Since the rubber cords are connected in multiple stages by the relay section, the propeller can be rotated for a longer time.

(4) Since the main body frame is composed of the rod material surrounding the propeller, damage to the propeller and the fuselage can be reliably prevented even if the model airplane falls or hits against something. .

[Brief description of drawings]

FIG. 1 is a perspective view showing a model airplane according to a first embodiment of the present invention.

2 is a plan view of the model airplane shown in FIG. 1. FIG.

FIG. 3 is a perspective view showing a model airplane according to a second embodiment.

FIG. 4 is a plan view of the model airplane shown in FIG.

FIG. 5 is a schematic diagram showing a usage state of the model airplane shown in FIG.

FIG. 6 is a perspective view showing a model airplane according to a third embodiment.

FIG. 7 is a plan view of the model airplane of FIG.

FIG. 8 is a perspective view showing a model airplane according to a fourth embodiment.

FIG. 9 is a perspective view showing a model airplane according to a fifth embodiment.

FIG. 10 is an exploded perspective view of main parts of the model airplane shown in FIG.

FIG. 11 is a front view showing a model airplane according to a sixth embodiment.

FIG. 12 is a plan view of the model airplane shown in FIG.

FIG. 13 is a perspective view showing a relay section.

FIG. 14 is a perspective view showing a model airplane according to a first modification.

FIG. 15 is a plan view of the model airplane shown in FIG.

16 is a side view of the model airplane shown in FIG.

FIG. 17 is a perspective view showing a model airplane according to a second modification.

18 is a plan view of the model airplane shown in FIG.

[Explanation of symbols]

1 ... Model airplane, 2 ... Propeller, 3 ... Rubber string, 4 ... Main body frame, 5 ... Wing.

Claims (8)

[Claims] 1. A propeller configured to obtain a propulsive force, a rubber strap attached to both sides of a rotation shaft of the propeller to hold the propeller and serve as a drive source for rotation, and a main body frame supporting the rubber strap. A model airplane characterized by that. 2. A propeller for obtaining a propulsive force, a string attached to both sides of a rotation shaft of the propeller for holding the propeller, and an elastic member for supporting the string and bending due to twisting of the string, the propeller A model aircraft, which is composed of a main body frame that serves as a drive source for rotation of the aircraft. 3. A propeller for obtaining a propulsive force, rubber strings attached to both sides of a rotation shaft of the propeller to hold the propeller, elastic members configured to support the rubber string, and bend due to twisting of the rubber string. According to the present invention, the model airplane characterized by comprising a main body frame which is a driving source of rotation of the propeller in combination with elasticity of the rubber cord. 4. A propeller for obtaining a propulsive force, a first rubber cord having one end attached to both sides of a rotation shaft of the propeller to hold the propeller and serve as a drive source for rotation, and each first rubber cord. The other end of each of which is rotatably supported and which transmits the rotational force in one or a plurality of directions, a main body frame which supports each of the relay parts, and a bridge between the main body frame and the relay part. A model airplane characterized by comprising a second rubber cord which is provided as a drive source for rotation of the propeller together with the first rubber cord. 5. A propeller for obtaining a propulsive force, a first rubber cord having one end attached to both sides of a rotation shaft of the propeller to hold the propeller and serve as a drive source for rotation, and each first rubber cord. A plurality of relay portions that rotatably support the other end portions of each of the relay portions and transmit a rotational force in one or a plurality of directions; and a main body frame that supports the relay portions.
It is composed of a plurality of rubber cords which are continuously hung over in a multi-stage manner between the respective relay parts and whose final stage is connected to the main body frame and which, together with the first rubber cords, serves as a drive source for rotation of the propeller. A model airplane characterized by being done. 6. The model aircraft according to claim 4 or 5, wherein the relay portion is fitted around a first bevel gear locked to the first rubber cord, and a rotational force by fitting around the first bevel gear. A model aircraft characterized by comprising one or a plurality of second bevel gears for transmitting. 7. The model aircraft according to claim 1, wherein the main body frame is provided with a wing that suppresses rotation of the main body frame by the propeller to maintain flight stability. 8. The model airplane according to claim 1, wherein the main body frame is formed of a rod member surrounding the propeller.