Small flying vehicle equipped with airbag device

A small flying vehicle flown by radio control or autonomously by an auto pilot is equipped with an airbag device. The small flying vehicle has a main body part including a controller and a battery, a frame, a propeller, a motor, and a transmitting and receiving antenna. The airbag device has a gas supplier, a sensor, a controller, and an airbag. The airbag device is attached to the main body part, and the gas supplier is provided with a gas cylinder that releases a compressed gas when a closure member sealing the gas cylinder is broken, a breaker, including an electric igniter, that breaks the closure member, and introduction device that introduces the gas discharged from the gas cylinder and providing the pressurized gas into the airbag to inflate the airbag.

FIELD OF THE INVENTION

The present invention relates to a small flying vehicle equipped with an airbag device.

BACKGROUND OF THE INVENTION

Small flying vehicles (so-called drones) that can fly by radio control or autonomously fly by autopilot are used in various fields. For example, they are used for photographing areas difficult to approach or enter, including disaster sites, volcanoes, mountains, forests, deserts, oceans, lakes, rivers, and various buildings, from lower altitude.

When a drone is used for such photographing purposes, an expensive imaging device, such as a video camera, and a data transmission device will be attached to the drone. In this case, if the drone crashes and collides with the ground, standing trees, buildings or the like due to an accident, not only the drone itself but also the imaging device and valuable recorded data may be damaged. Further, there will be a danger of damaging a facility or equipment at the spot where the drone has crashed, or causing injury if any person is present at the falling point. In addition, when the drone crashes into a lake or the like, there will be a risk of not being able to collect the imaging device or the like due to submergence.

As disclosed in JP-A 8-192797, JP-A 2009-514740, and JP-A 2009-208674, there are inventions relating to large flying vehicles equipped with airbags (balloons) and parachutes.

SUMMARY OF THE INVENTION

The present invention intends to provide a small flying vehicle capable of mitigating the damage to a facility or equipment or any person at the falling point and the shock applied to drone itself, when falling and colliding with the ground or the like.

The present invention provides a small flying vehicle equipped with an airbag device, capable of flying by radio control or autonomously flying by autopilot, and having a maximum length of 2 m or less, wherein

the small flying vehicle has a main body part including a controller and a battery, a frame, a propeller, a motor, and a transmitting and receiving antenna,

the airbag device has gas supply means and an airbag and is attached to the main body part,

either the main body part or the airbag device further includes a sensor and a control device, and

the gas supply means is provided with a gas cylinder capable of releasing an internal pressurized gas when a closure member is broken and opened, breaking means including an electric igniter for opening the closure member of the gas cylinder, and introduction means for introducing the pressurized gas in the gas cylinder into the airbag to inflate the airbag.

Since the small flying vehicle (drone) according to the present invention is equipped with an airbag device, in the case of crashing and colliding with the ground, standing trees, buildings, or the like due to an accident, it is possible to mitigate the shock at the time of collision by inflating and deploying the airbag. Therefore, even when an expensive imaging device, a data transmission device, and the like are attached to the small flying vehicle, these devices can be protected and prevented from being damaged. Even when a facility or equipment or any person is present at the falling point, the damage can be reduced.

EMBODIMENTS OF THE INVENTION

A small flying vehicle according to the present invention can fly by radio control or autonomously fly by autopilot and has a maximum length of 2 m or less, which is generally referred to as a drone. The maximum length is a length of the longest part of the small flying vehicle and is, for example, the length between two propellers6aand6binFIG. 1.

The small flying vehicle has a main body part including a controller and a battery, a frame, a propeller, a motor, and a transmitting and receiving antenna, and also has other necessary components that are different depending on the model. The controller and the battery may be accommodated in the main body part or may be exposed thereon. The frame may be directly or indirectly attached to the main body part or may be integrated with the main body part.

The transmitting and receiving antenna may be an antenna having both of transmission and reception functions, an antenna dedicated for reception, or an antenna with a reception antenna and a transmission antenna that are provided separately. The controller can receive a signal from the antenna and control the rotation of the motor and the like, and can provide feedback of the rotational speed of the motor and other operational states of the small flying vehicle.

FIGS. 1 and 2illustrate one embodiment of a small flying vehicle1, which has a main body part2including a controller and a battery, frames4aand4bextending symmetrically from the main body part, motors5aand5battached to distal ends of these frames, and propellers6aand6bdriven by these motors. The antenna is not illustrated.

Although there are two frames according to the small flying vehicle1illustrated inFIGS. 1 and 2, the number of the frames may be within a range of 2 to 10 or more. The number of the motors and the number of the propellers may be the same as that of the frames. The frames can extend symmetrically in radial directions, for example, from the main body part2serving as a center, or from four corners of the main body part2according to the illustrated example.

Further, the small flying vehicle1illustrated inFIGS. 1 and 2has skid-type landing gears7aand7battached to the main body part2. The landing gears7aand7bmay have other shapes such as wheels. Alternatively, the landing gears may be replaced with frames.

In one embodiment, an imaging device is attached to the main body part or the frame of the small flying vehicle according to the present invention. In the small flying body, for example, an imaging device such as a video camera or a camera may be attached, by use of other fitting components as needed, to the main body part2, either one of the frames4aand4b, or both frames by straddling them. However, these configurations are not restrictive, and other articles may be attached to the small flying vehicle1. The small flying vehicle may be used for transportation purposes.

Although a case10accommodating an airbag device is attached to a bottom surface2aof the main body part2, it may be attached to any one of four side surfaces3. Alternatively, the case10may further be attached to an top surface2bother than the bottom and side surfaces, or may be attached using a combination thereof. The case10may also be attached to the landing gears7aand7bby using other fitting components.

As the case10, one similar to a module case for accommodating an airbag and an inflator mounted to an automotive vehicle can be used. In one embodiment, the airbag device has gas supply means, a sensor, a control device and a folded airbag. Each of the gas supply means, the sensor, and the control device is electrically connected to a power source (battery) via a conductor.

As the battery, one accommodated in the case10may be used, or a battery in the main body part2of the small flying vehicle1may be used. These batteries may also be general batteries, rechargeable batteries, or solar cells, and may be configured to be attachable and detachable.

At least one of the sensor and the control device may be attached to the main body part2of the small flying vehicle1. Further, functions of the control device may be incorporated as part of controller functions of the small flying vehicle1.

As the gas supply means illustrated inFIG. 3, gas supply means (first gas supply means)35similar to the pressurized gas supply means illustrated in FIG. 3 of JP-A 2015-62545 can be used. The first gas supply means35includes a trifurcate tube40made of a material such as aluminum or stainless steel, which is composed of a main pipe41having openings provided at both ends thereof, and one branch pipe42vertically branched from a peripheral surface of the main pipe41, namely in a direction orthogonal to the main pipe41.

In one embodiment, an opening portion including a closure member47of a gas cylinder45is connected to one end opening41aof the main pipe41. The main pipe41and the gas cylinder45may be connected by welding, or may be connected by screwing the gas cylinder45into the one end opening41aof the main pipe41.

An inert gas such as argon, helium, nitrogen, and carbon dioxide is pressurized and filled in an interior space46of the gas cylinder45. The filling amount of the gas is such that at least the airbag to be used can be fully inflated. In one embodiment, the opening of the gas cylinder45is closed with the circular closure member47. The closure member47is deformed into a bowl shape under the pressure of the interior space46.

In one embodiment, breaking means is connected to the other end opening41bof the main pipe41. The breaking means may be composed of an electric igniter50equipped with an ignition agent; and a flying body55for advancing straight on receiving a flame or a shock wave of combustion products due to activation of the electric igniter50to break and open the closure member47.

As the electric igniter50, one similar to an electric igniter used for a gas generator of a known airbag device can be used. It is preferred to use ZPP (a mixture containing zirconium and potassium perchlorate) or THPP (a mixture containing titanium hydride and potassium perchlorate) as the ignition agent because of its high sensitivity. If necessary, a gas generation agent may be accommodated in a space70between the electric igniter50and the flying body55.

The electric igniter50may be composed of an igniter holder52made of metal and resin materials and an igniter main body51surrounded and held by the igniter holder52. The electric igniter50may be connected by calking the other end opening41bof the main pipe41, or may be connected by screwing the igniter holder52into the other end opening41bor by using any other means.

In one embodiment, the flying body55is composed of a disk portion56, a shaft portion57vertically provided from the center of the disk portion56, and an arrowhead portion (an acute portion)58formed at a distal end of the shaft portion57. The acute portion is not limited to the arrowhead portion58and may be a rod-like member whose tip is cut diagonally with respect to the axial direction (for example, one having a bamboo spear shape).

The flying body55is disposed in the main pipe41in such a manner that the disk portion56is positioned on the side of the electric igniter50and the arrowhead portion58is positioned on the side of the closure member47. A tip of the arrowhead portion58is disposed so as to be positioned further toward the closure member47than an opening42aof the branch pipe42connected to the main pipe41. More specifically, the arrowhead portion58is closer to the closure member47than the opening42a.

L1represents the distance between the tip of the arrowhead portion58and the closure member47and L2represents the distance between the disk portion56and the opening42a. In one embodiment, the flying body55is disposed in the main pipe41so as to satisfy a relationship of L1<L2. When the tip of the arrowhead portion58moves by the distance L1and collides with the closure member47, the disk portion56moves by the same distance L1. However, because of the relationship of L1<L2, the disk portion56is positioned on the side of the electric igniter50from the opening42aof the branch pipe42. More specifically, the arrangement of the flying body55is adjusted in such a manner that the disk portion56cannot reach the opening42aat the time of activation.

If the disk portion56reaches and comes into contact with the opening42aof the branch pipe42before the tip of the arrowhead portion58collides with the closure member47, there is a risk of the tip of the arrowhead portion58not colliding with the central point of the closure member47. However, since there is the relationship of L1<L2, the above-mentioned risk can be negated. In addition, there is no risk that the opening42ais closed by the disk portion56.

In order to surely break the closure member47with the flying body55at the time of activation, it is preferred that the flying body55can advance straight in the main pipe41on receiving the shock wave due to the activation of the electric igniter50, and the tip of the arrowhead portion58can collide with the central point of the closure member47. However, if the breakage is ensured, the collision may be located in the vicinity of the central point.

In order to ensure the above-mentioned operation, it is preferred that the outer diameter of the disk portion56is adjusted so as to be close to the inner diameter of the main pipe41(the outer diameter of the disk portion56<the inner diameter of the main pipe41, while close to each other), so that the main pipe41can function as a guide member.

Further, in addition to the function for guiding the disk portion56, arranging the flying body55so as to satisfy the above-mentioned relationship of L1<L2makes it easy to break the closure member47with the flying body55.

To prevent the flying body55from moving in the axial direction when not activating, two convex portions43and44are formed on an inner peripheral surface of the main pipe41with an interval provided therebetween in the axial direction, so that the disk portion56can be positioned between these convex portions43and44. Each of the convex portions43and44has a smaller protrusion height. Therefore, at the time of assembling, the flying body55can be inserted into the main pipe41by press fitting the flying body55from the side of the other end opening41bwith a smaller force. The convex portions43and44do not hinder the movement of the flying body55(the disk portion56) at the time of activation.

As an additional configuration, an elastic member such as a spring may be used to urge the flying body55toward the side of the igniter50before activation, and to return the flying body to the side of the igniter50with its spring force also after the activation. Alternatively, instead of using the flying body55, a gas generation agent may be accommodated in an internal space71of the main pipe41and used as breaking means.

Introduction means60is connected to the branch pipe42. The introduction means60introduces a pressurized gas from the gas cylinder to the airbag.

In one embodiment, as illustrated inFIG. 3, the introduction means60is composed of a flexible tube62and a mouth ring61provided at an end of the flexible tube62. The mouth ring61is connected to the main pipe41by being screwed into the branch pipe42. The flexible tube62is a tube made of a flexible material, such as a resin or a rubber, and is connected to the airbag.

In another embodiment of the present invention, the small flying vehicle has plural pieces of introduction means and a plurality of airbags whose total number is the same as the number of pieces of the introduction means. According to one example, the first gas supply means35illustrated inFIG. 3may be replaced by second gas supply means135illustrated inFIG. 4.

The second gas supply means135illustrated inFIG. 4includes a trifurcate tube140made of a material such as aluminum or stainless steel. The trifurcate tube140is composed of a main pipe141and two branch pipes of a first branch pipe142and a second branch pipe143, which are vertically branched from a peripheral surface of the main pipe141, namely in an orthogonal direction with respect to the main pipe141. According to the illustrated example, the first branch pipe142and the second branch pipe143are disposed at positions opposing in the diameter direction of the main pipe141.

First introduction means60ais connected to the first branch pipe142. As illustrated inFIG. 4, the first introduction means60ais composed of a first flexible tube62aand a first mouth ring61aprovided at an end of the first flexible tube62a.

The first mouth ring61ais connected to the main pipe141by being screwed into the first branch pipe142. The first flexible tube62ais a tube made of a flexible material, such as a resin or a rubber, and is connected to an airbag.

Second introduction means60bis connected to the second branch pipe143. As illustrated inFIG. 4, the second introduction means60bis composed of a second flexible tube62band a second mouth ring61bprovided at an end of the second flexible tube62b.

The second mouth ring61bis connected to the main pipe141by being screwed into the second branch pipe143. The second flexible tube62bis a tube made of a flexible material, such as a resin or a rubber, and is connected to an airbag. The rest of the configuration is similar to that of the first gas supply means35illustrated inFIG. 3.

The first gas supply means35illustrated inFIG. 3is configured to inflate and deploy one airbag. On the other hand, the second gas supply means135illustrated inFIG. 4can inflate and deploy two airbags.

Further, instead of using the first gas supply means35or the second gas supply means135, third gas supply means having three branch pipes (a first branch pipe, a second branch pipe, and a third branch pipe) and a plurality of related members may be used for inflating and deploying three airbags.

Alternatively, instead of using the second gas supply means135or the third gas supply means, the flexible tube62of the first gas supply means35may be replaced with a bifurcate tube or a trifurcate tube to connect two airbags or three airbags, respectively.

Although not illustrated, the main body part or the airbag device of the small flying vehicle according to the present invention has a sensor. This sensor is for operating the airbag device in cooperation with the control device (not illustrated) that is provided in the main body part or the airbag device, and examples of the sensor that can be used include a velocity sensor for detecting the fall velocity when the small flying vehicle1is falling in an abnormal flying state, an angle sensor for detecting the angle of the small flying vehicle1at the time of flight, and other known sensors.

In addition to the control based on the sensor, the airbag device may be configured to be manually controlled according to an instruction of an operator. As the control device (CPU), one used for a known airbag device mounted to an automotive vehicle or the like can be used. Further, as mentioned above, the control device may be part of the controller of the small flying vehicle1.

As the airbag, any airbag used for a known airbag device mounted to an automotive vehicle or the like can be used. However, unlike the airbags of known airbag devices, no vent port is provided for discharging the gas.

The shape of the airbag at the time of inflation and deployment is not particularly limited and can be appropriately selected according to the structure and shape of the small flying vehicle1. For example, it may be a spherical shape, a disc-like shape (being circular in a planer shape), an elliptical plate shape (being elliptical in planer shape), a polygonal plate state (being polygonal in planer shape), an eggplant-like shape, a rod-like shape, a floating ring shape, a boat shape, or any combination of the above-mentioned shapes in which two or more airbags are connected at one point or two or more points (for example, a shape like a catamaran or a trimaran of a yacht).

If necessary, the small flying vehicle1according to the present invention can be equipped with a parachute device attached to the main body part or the frame. The parachute device is usable as an auxiliary device of the airbag device for decelerating the fall velocity of the small flying vehicle1when it falls. For this reason, the diameter of a parachute deploying at the time of activation is preferably comparable to the size of the main body part2, or within a length range covering the main body part2and ⅓ of respective frames4aand4bextending symmetrically from the main body part2. The activation of the parachute device may be interlocked with the airbag device, for example, by the above-mentioned control device, or may be separately instructed wirelessly.

Next, an operation of the small flying vehicle1at the time of activation of the airbag device will be described with reference toFIGS. 5 to 8.

FIG. 5illustrates an embodiment using an airbag device having three airbags51,52, and53, although the airbag device may have the airbag51only or two of the airbags52and53.FIG. 5illustrates a state where all the three airbags51,52, and53are deployed.

Turning on a switch of the power source brings the airbag device in the case10into a state where the sensors, the control device, and the pressurized gas supply means (the electric igniter) are operable. When the airbag device has only one airbag51, the gas supply means35illustrated inFIG. 3can be used. When the airbag device has two airbags52and53, the gas supply means135illustrated inFIG. 4can be used. When the airbag has three airbags51to53, the third gas supply means can be used.

In the following description, the case where the airbag device has only the airbag51is chiefly described.

When the small flying vehicle1is brought into a state where it crashes and collides with the ground or the like due to a failure or the like, the sensor detects an abnormality and sends a signal to the control device. The electric igniter50of the first gas supply means35(or the second gas supply means135or the third gas supply means) activates in response to a command from the control device.

The activation of the electric igniter50produces combustion products (a flame, a shock wave, and the like) of the ignition agent, which collide with the disk portion56of the flying body55. Therefore, the flying body55advances straight in the main pipe41and collides with the center of the closure member47, thereby surely breaking the closure member47. When the closure member47is broken and opened, the pressurized gas filling the gas cylinder45is discharged therefrom, enters the trifurcate tube40, and flows into the airbag51via the branch pipe42to inflate and deploy the airbag51.

Using the second gas supply means135can inflate and deploy the airbags52and53. Using the third gas supply means can inflate and deploy the airbags51to53.

Although the examples illustrated inFIGS. 3 and 4use the flying body55to break the closure member47, it may be replaced with gas supply means using the above-mentioned gas generation agent or having a breaking structure with only the electric igniter50(for example, the one illustrated in FIG. 1 of JP-A 2003-25951).

The time from the abnormality detection by the sensor to the inflation of the airbag51caused by the activation of the electric igniter50can be set to several tens of milliseconds to several seconds. However, it is preferred to adjust the inflation time of the airbag51according to the shape and size of the small flying vehicle1and further, according to a portion where mitigation of the shock is mainly required. For example, the activation time is preferably 30 milliseconds or more, more preferably 50 milliseconds or more, and further preferably 80 milliseconds or more; and is preferably 2 seconds or less, more preferably 1.5 seconds or less, and further preferably 1.2 seconds or less.

Accordingly, as the shock when the small flying vehicle1collides with the ground or the like is mitigated, not only damage to the small flying vehicle1itself can be reduced but also damage to the imaging device or the like can be prevented. In addition, when the small flying vehicle1crashes into the sea, lake, river, or the like, the small flying vehicle1itself can be kept in a floated state.

When the second gas supply means135or the third gas supply means is used, the airbags52and53or the airbag51to53can be inflated and deployed so that the shock mitigation effect and the buoyant force can be further enhanced. The total airbag capacity may be the same or different between the case of using only one airbag and the case of using a plurality of airbags.

FIGS. 6 and 7illustrate an embodiment in which airbag54is used as an airbag whose planer shape when inflating and deploying becomes a circular plate.FIG. 8illustrates an embodiment in which two airbags55aand55bare connected by connection part55cso as to serve an airbag whose planer shape when inflated and deployed becomes a shape similar to two trunks of a catamaran. Alternatively, an airbag inflating and deploying so as to wrap the main body part2can also be used.

INDUSTRIAL APPLICABILITY

The small flying vehicle according to the present invention can also be used for aerial photographing at various places, spraying of agricultural chemicals, transportation of parcels, and the like.

REFERENCE SIGNS LIST