VERTICAL LANDING EQUIPMENT FOR RADIO CONTROL MULTI- AID AIRCRAFT AND A METHOD THEREOF

Technical Field The present invention relates to a landing device for a radio control multi-purpose aircraft that is applied to a wire stranding technique at the wiring work of a power transmission line, a bridge, a cable car and the like, and more particularly, to a vertical landing device for a radio control multi-purpose aircraft that has the aircraft descended vertically from the air irrespective of the ground conditions of a landing site to allow the aircraft to be safely landed to a target area without any damage on the aircraft.

Background Art

In order to conduct the wiring work for power lines on a power transmission line construction, generally, a messenger wire is first connected in an intended wire stranding section, and the power line is drawn by using the connected messenger wire.

The method for connecting the messenger wire includes one wire stranding technique wherein the messenger wire is forcedly spread over the route between steel towers by workers and pulls by means of a puller device in such a manner as to be raised over the steel towers, and another wire stranding technique wherein the messenger wire is connected by using a rope or directly through a helicopter in the air over the steel towers. However, since the route of the power transmission line construction is mostly in mountainous areas with dense

forests, so as to adopt the wire stranding technique that is assisted directly by workers, enormous lumbering and environmental damages are not avoided to raise to the air the wire placed curved to pass through obstacles on the ground. Therefore, the wire stranding technique that is assisted by using the helicopter is adopted to most of construction sites .

However, the wire stranding technique that is assisted by using the helicopter needs a parking area for the taking off and landing of the helicopter, the movements of auxiliary equipment like an oil tanker according to the helicopter operation, and the movements of the helicopter from the mooring area to the parking area of the construction site, which results in an increase of the construction costs. Furthermore, as noises and winds are generated during the helicopter operation, popular complaints may be made in the construction site.

Additionally, the helicopter with the wire or rope hanging therefrom may be crashed during the aeronautical operation, and as the change of weather is severe, the helicopter' s crashing danger increases to thereby limit the operation. Moreover, since the helicopter is not allowed to do the aeronautical operation in the operation prohibited area, undesirably, the working efficiency is decreased and the construction period is extended further.

To solve the above-mentioned problems, there is disclosed Korean Patent Application No.10-2003-0060003 as filed by the same applicant as the present invention, wherein a radio control multi-purpose aircraft (fixed wing aircraft) is adopted to a wire stranding technique such that it can be taken off and landed even in a small area,

considering the working conditions of the steel tower construction site.

Since the radio control multi-purpose aircraft should have an additional ground area for the taking-off and landing of the aircraft, it is not utilized well when compared with the helicopter (variable wing airplane) .

To overcome these problems, the aircraft is taken off even in a small area by using a small-sized oscillating device properly adapted for the aircraft, and the aircraft is landed by colliding against a net installed at the landing area or by releasing a safety chute that is mounted therein in the air.

According to the landing method for colliding the aircraft with the net, it is difficult to set an accurate target area, in case where an unexpected change of weather like strong winds is made, such that the aircraft may enter inaccurately the net, which causes the damage on the aircraft, and even when it enters accurately the net, it may be damaged or broken. Furthermore, since there is a need for the preparation of the integrated devices accompanied by the installation of the net, there occur some problems that the installation process becomes complicated and additional costs are raised.

On the other hand, according to the landing method for mounting the safety chute at the aircraft, since the chute is released during descending, the descending speed of the aircraft is drastically decreased, such that as the energy generated at this time is transmitted to the aircraft, the aircraft may be turned over or tangled with the chute and rope, which may cause the damage on the aircraft .

Disclosure of Invention Technical Problem

Accordingly, the present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a vertical landing device for a radio control multi-purpose aircraft that is provided with a chute adapted to absorb an energy generated during the descending movement of the aircraft so as to allow the aircraft to be landed stably, thereby preventing the damages on the aircraft caused at the time of landing.

Technical Solution

To achieve the above object, according to an aspect of the present invention, there is provided a vertical landing device for a radio control multi-purpose aircraft having a body part and a wing part, wherein the vertical landing device has a chute having at least one pair of high- flexible guide cords and at least one pair of inflexible guide cords so as to allow the chute to be connected with the body part.

The pairs of high-flexible guide cords include a pair of first guide cords connected to an engine cover and a pair of second guide cords connected to a front side wing- connecting bar, and the pair of inflexible guide cords are connected to a rear side wing-connecting bar.

The vertical landing device further includes: a cover separably mounted on the top portion of the body part of the aircraft; a fixing part for fixedly mounting the cover to the body part and having a groove formed on the front

surface of the cover for fixedly inserting a rotary wing of a servo motor thereinto, first and second protrusions formed on the back surface of the cover for functioning as a hinge with respect to the body part, and an elastic means disposed at the inside of the body part in such a manner as to be pressed below the cover, for pushing the cover toward the outside of the body part when the cover is separated from body part; the servo motor mounted at the inside of the body part for providing a driving force to the fixing part such that the cover is separated from the body part; and the chute housed at the inside of the cover.

To achieve the above object, according to another aspect of the present invention, there is provided a method for landing a radio control multi-purpose aircraft by using a chute accommodated at the inside thereof, the method including the steps of: detaching a cover with the chute housed therein from a body part by means of a radio remote control to draw the chute from the cover while the cover escapes toward the rear side of the aircraft; extending at least one pair of high-flexible guide cords connecting the chute and the body part up to a maximum length charging an air pressure to the inside of the chute and drastically reducing a descending speed of the aircraft; and transmitting an impact quantity generated by a variation of the descending speed to the chute.

Advantageous Effects

According to the present invention, since a chute is mounted as a landing device for a radio control multipurpose aircraft, there is no need for a separate large

area for landing the aircraft, such that the installation of the landing equipment is not complicated and the construction costs is reduced.

Further, since a flexible bungee cord is adopted as a guide cord connected to the chute, the energy generated during the descending movement of the aircraft is absorbed to the chute, such that the aircraft can be down stably at a time of landing, thereby preventing the safety accidents and damages of the aircraft happening during the landing.

Description of Drawings

FIGS.l to 8 are views showing the construction of a radio control multi-purpose aircraft employed according to the present invention, wherein FIGS.l and FIG.2 are perspective views showing the whole appearance of the radio control multi-purpose aircraft employed according to the present invention;

FIG.3 is a view showing a landing device of the radio control multi-purpose aircraft according to the present invention;

FIG.4 is a sectional view showing the whole side of the vertical landing device of the present invention;

FIGS.5 and 6 are views showing the vertical landing device being fixed to the body part of the aircraft; FIG.7 is a view showing the operation principles of the landing device of the present invention;

FIG.8 is a view showing the landing device operated in such a manner as to be connected with a chute; and

FIGS.9 to 14 are views showing the landing steps of the radio control multi-purpose aircraft according to the present invention.

<Explanation on the reference numerals on the main pats in the drawing>

100: body part 110: central body

120: engine cover 130: propeller 140: rudder 200: wing part

210: wing 220: aileron

230: aileron-cooperating part

240,250: wing-connecting bar

300: landing device 310: cover 320: servo motor 321: rotary wing

330: chute 331: chute rope

340: cover groove 350: central body groove

360: elastic means 370: protrusion

380: connection loop 400: connection cord 410: first guide cord 420: second guide cord

430: third guide cord 440: connection cord ring

Best Mode for Carrying Out the Invention Hereinafter, an explanation of a vertical landing device for a radio control multi-purpose aircraft according to the present invention will be given with reference to the attached drawings .

First, the radio control multi-purpose aircraft employed according to the present invention includes a general fixed wing aircraft.

FIGS.l to 8 are views showing the construction of a radio control multi-purpose aircraft employed according to the present invention, wherein FIGS.l and FIG.2 are perspective views showing the whole appearance of the radio control multi-purpose aircraft employed according to the

present invention, FIG.3 is a view showing a landing device of the radio control multi-purpose aircraft according to the present invention, FIG.4 is a sectional view showing the whole side of the vertical landing device of the present invention, FIGS .5 and 6 are views showing the vertical landing device being fixed to the body part of the aircraft, FIG.7 is a view showing the operation principles of the landing device of the present invention, and FIG.8 is a view showing the landing device operated in such a manner as to be connected with a chute.

As shown in FIGS.l and 2, the radio control multipurpose aircraft employed according to the present invention is configured wherein a wing part 200 is connected to both sides of a body part 100 and a landing device 300 is mounted on the top of the body part 100 in such a manner as to be operated by radio remote controls manipulated by a worker.

The body part 100 is disposed in the middle portion of the aircraft and includes a central body 110 for bonding each part of the aircraft thereto and for mounting equipment thereon, a propeller 130 disposed on the front face of the central body 110 and rotated by an engine device, an engine cover 120 disposed at the front portion of the central body 110, and a rudder 140 disposed on the rear portion of the central body 110 for generating a floating force in a direction of the wind blowing to the key faces to allow the aircraft to conduct side slipping or turning movements or to stop the side slipping or turning movements of the aircraft. Further, the body part 100 at the inside thereof includes the engine device for generating power for aircraft service, a fuel tank, a

battery for supplying power necessary into the aircraft, a remote signal reception and control unit for receiving the remote control signals transmitted from a radio remote controller of a worker to conduct the control operations for the aircraft service and for dropping a pilot line under the received control signals, and a rudder control unit for controlling the rudder 140 under the control of the remote signal reception and control unit. The body part 100 has a line dropping device disposed at the rear side thereof, for dropping the pilot line therefrom.

The wing part 200 includes a pair of wings 210 extended from the middle portion of the central body 110 to the left and right sides, a pair of ailerons 220 mounted at the outside of the trailing edges of the wings 210 and adapted to turn the aircraft to left and right sides, an aileron- cooperating part 230 for operating the ailerons 220 in cooperation relation with the remote signal reception and control part to adjust angles of the ailerons 20 with respect to the wings 210, and a pair of wing-connecting bars 240 and 250 disposed between the both sides of the central body 110 for fixedly supporting the wings 210.

The landing device 300 includes a cover 310 separably mounted on the top portion of the body part 100, a fixing part for fixedly mounting the cover 310 to the body part 100, a servo motor 320 mounted at the inside of the body part 100 for providing a driving force to the fixing part such that the cover 310 is separated from the body part 100, and a chute 330 housed at the inside of the cover 310 in such a manner as to be connected to the body part 100 and the cover 310.

As shown in FIG.3, the fixing part is configured wherein a cover groove 340 is formed on the front face of the cover 310 in such a manner as to insert a rotary wing 321 of the servo motor 320 thereinto, and an elastic means 360 like a bungee cord is mounted at the inside of the body part 100 in such a manner as to be pressed against the lower side of the cover 310 when the rotary wing 321 is inserted into the cover groove 340, such that the cover 310 is fixed on the top portion of the body part 100. In other words, as shown in FIGS.4 and 5, the elastic means 360 that is formed of the bungee cord is fixed at left and right end portions to the inside of the body part 100, and if the cover 310 is fixedly mounted, the elastic means 360 is pressed, as shown in FIG.6, such that the cover 310 can be separated at any time only if the fixing part is removed.

The elastic means 360 may be formed of an elastic material like a spring, a rubber band, and the like, and it is desirably mounted on the body part 100 for easily separating the cover 310 from the body part 100.

If the rotary wing 321 of the servo motor 320 is rotated by the remote control, the fixed landing device 300 is operated, as shown in FIG.7, as the cover 310 housing the chute 330 therein is deviated from the body part 100. In this case, the cover 310 has protrusions 370 formed on the back face thereof, the protrusions 370 serving as a hinge, such that as the cover 310 is rotated with respect to the hinge structure, it is separated from the body part 100. Further, the cover 310 has a connection loop 380 disposed on the inside thereof for connecting the chute 330 thereto. Also, the cover 310 is made of a light F. R. P

(fiber-glass reinforced plastic) material and desirably has a bottom face closed on about one-third area and opened on two-third area, such that the chute 330 housed in the cover 310 can be easily deviated from the cover when the cover 300 is deviated from the body part 100 for a landing operation .

The servo motor 320 is cooperated with the remote signal reception and control part in the body part 100, and if a remote signal reception and control part receives a landing signal transmitted from the radio remote control part, the rotary wing 321 of the servo motor 320 is rotated by 90 ^° such that the cover 310 is deviated from the body part 100 to conduct the landing operation. In this case, the rotary wing 321 is repeatedly rotated by 90 ^° in the preferred embodiment of the present invention, and may be rotated by 180 ^° or 360 ^° . In case where the servo motor 320 is housed at the inside of the central body 110, also, the central body 110 has a central body groove 350 formed at the operating range thereof for rotating the rotary wing 321 thereinto.

If the landing device as constructed above is operated to demount the chute housed therein, the chute is connected by means of a plurality of guide cords to the aircraft. Each of the plurality of guide cords is comprised of a pair of left and right cords for connecting the chute 330 with the body part 100, and the guide cords are at least one pair of high-flexible guide cords and a pair of inflexible guide cords. Preferably, as shown in FIG.8, the number of pairs of guide cords is three.

In case where the pair of first guide cords 410, the pair of second guide cords 420, and the pair of third guide cords 430 are provided, the pair of first guide cords 410 are mounted on the engine cover 110, the pair of second guide cords 420 are on the front side wing-connecting bar 240, and the pair of third guide cords 430 are on the rear side wing-connecting bar 250. Also, a connection cord 400 is connected to the upper side of the pairs of first to third guide cords 410, 420 and 430, and the connection cord 400 is connected by means of a connection cord ring 440 to a chute rope 331 of the chute 330. In this case, the pairs of first and second guide cords 410 and 420 are high- flexible guide cords, and they are preferably formed of a bungee cord that is extendable by 500%. Further, the pair of third guide cords 430 are inflexible guide cords, and they are preferably formed of a nylon rope.

So as to ensure safety landing at an emergency situation like crashing and to prevent the damage on the aircraft, an explanation of the landing operation of the remote control multi-purpose aircraft according to the present invention will be in detail given with reference to FIGS.9 to 14.

First, after the line dropping device is operated to carry out wiring work by using the radio remote controller of a worker, the speed of the aircraft is reduced to have a vertical descending attitude in the air over an expected landing area through the radio remote control. After that, if the servo motor 320 is activated, the cover 310 is separated from the body part 100 as shown in FIG.9. The rotary wing 321 of the servo motor 320 that serves to fix the cover 310 of the landing device 300 is deviated from

the cover groove 30 formed on the front face of the cover 310, and thereby, the cover 310 becomes released from the body part 100 in such a manner as to be detachable therefrom. That is to say, if the rotary wing 321 is deviated from the cover groove 340 at the state where the chute 330 is housed in the cover 310, the cover 310 springs protruded upwardly by means of the elastic means 360 disposed below the cover 310. Then, the protrusions 370 formed on the rear face of the cover 310 serve as a hinge, such that as the cover 310 is turned over, the cover 310 is completely separated from the body part 100.

After that, as a wind from the front face of the aircraft is against the cover 310 separated from the body part 100, the cover 310 pushes against the wind formed by the vertical descending movement and the wind formed by the propeller 130 and moves to the rear side of the aircraft, as shown in FIG.10, such that as tension is applied sequentially to the pair of first guide cords 410, the pair of second guide cords 420, and the pair of third guide cords 430, the chute 330 is deviated from the cover 310.

In this case, the chute 330 is connected through the three pairs of guide cords to the aircraft side. That is, the pair of first guide cords 410 and the pair of second guide cords 420 that are formed of high-flexible guide cords are connected with the engine cover 110 and the front side wing-connecting bar 240, and the pair of third guide cords 430 that are formed of inflexible ropes are connected to the rear side wing-connecting bar 250.

After the chute 330 is deviated from the cover 310, further, the landing operation is continued at the state where the cover 310 is connected to one side of the chute

330 by means of the connection loop 380 formed at the inside thereof.

As the chute 330 that is deviated from the cover 310 by the tension of the pair of first guide cords 410 is released by wind, as shown in FIG.11, an air pressure is charged to the inside of the chute 330. At this time, the tension is applied sequentially to the pair of first guide cords 410, the pair of second guide cords 420, and the pair of third guide cords 430. In this case, the pairs of first and second guide cords that are high-flexible guide cords are extended to the maximum. Thus, as the descending energy of the aircraft is absorbed to the chute 330 through the pairs of first to third guide cords 410, 420 and 430 sequentially, the descending speed of the aircraft is drastically decreased.

An impact quantity generated by the variation of the descending speed of the aircraft is sent fully to the chute 330 through the pair of third guide cords 430, as shown in FIG.12, at the moment where the energy is completely applied to the chute 220, the descending movement momentarily stops and the nose of the aircraft is up, such that the aviation is changed to an ascending movement.

Next, the aircraft that momentarily stops the descending movement starts again to the descending movement by its own weight. At this time, as shown in FIG.13, the chute 330 is normally placed over the aircraft, and the air pressure applied to the chute 330 is sufficiently resistant to the weight of the aircraft, such that the aircraft is slowly descended toward the landing area. The aircraft that keeps descending is finally landed on the landing area, without any impact thereon, as shown in

FIG.14, and the air pressure of the chute 330 is naturally vanished, such that the chute 330 is at the rear side of the aircraft. Thereby, the landing operation is completed without any damage on the aircraft. To carry out the landing operation, therefore, there is no need for a separate large landing area, and since the descending speed of the aircraft is absorbed to the chute by using the tension of the flexible bungee cords, the attitude of aviation of the aircraft during the descending movement can be maintained, such that the aircraft can be down stably at a time of landing, thereby preventing the safety accidents and damages of the aircraft happening during the landing.

The invention has been described in al illustrative manner. It is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the invention may be practiced other than as specifically described.