The present invention relates to a mechanism provided in air vehicles, which enable the air vehicle to be steered by means of force transmission.

A linear relationship exists between an input to the lever arm used in the mechanisms and an output received from the lever. In a mechanism system with a high precision, low motion output values should be provided against high motion input values. According to mechanical control systems for nose wheel steering, pilot input and nose wheel output have a linear relationship due to the mechanism elements in the system. For each degree of angle input by the pilot, the wheel rotates one degree.

The United States patent application US20120112000A1 , which is included in the known- state of the art, discloses an aircraft landing gear, and more specifically, a system for controlling the front landing gear for retraction and steering. While the aircraft taxis on the ground, the pilot instructs the nose gear control system to rotate in one direction or the other. This system then sends an insertion command to one of the second bars, while at the same time sending a retraction command of the same amplitude to the other, second bar. Lateral extensions in the invention move in equal lengths and in opposite directions, so the t-shaped part moves to rotate around its own axis. Therefore, through the torque coupling, it causes the center of the wheels to move at an angle equal to the angle exposed.

Thanks to a steering system according to the present invention, a more precise and controllable mechanism output is provided in response to an input provided by the pilot in an air vehicle.

An object of the present invention is to obtain a non-linear input-output graph for mechanical nose wheel steering mechanisms in air vehicles. The steering system realized to achieve the object of the present invention, which is defined in the first claim and other claims dependent thereon, comprises an input element provided in air vehicles, which provides a force input to generate movement energy; an output element which performs a movement requested by a user using the force applied by the input element. A transmission mechanism is provided between the input element and the output element for transmitting the force received from the input element to the output element. Thus, the desired movement is performed by the pilot. It comprises a first connecting element that connects the input element and the transmission mechanism; a second connecting element that connects the transmission mechanism and the output element; at least one arm on the transmission mechanism. An initial force is applied to the input element by the pilot. The force is received from the input element via the first connecting element and transmitted to the transmission mechanism. The movement is maintained by at least one arm on the transmission mechanism, so that the force reaches the second connecting element and received by the same, and transmitted to the output element. In this way, the final movement requested by the user is performed on the output element.

The steering system according to the invention comprises the first connecting element moving linearly on a direction it extends so as to transmit the force provided by the input element to the transmission mechanism. A threshold force value is predetermined by the user for a final movement output in the output element. When the force applied by the pilot is less than the threshold value predetermined by the user, less force reaches the second connecting element than the force transmitted to the transmission mechanism by the first connecting element. The output element is also actuated by the second connecting element. Up to the predetermined threshold value, the ratio of the amount of force input by input element to the amount of force output by the output element is greater than one. Therefore, it is enabled that the force transmitted to the output element performs the movement with precision in cases where a precise output is desired, such as the air vehicle maneuvering quickly when moving slow, requesting slow wheel movement when moving fast, and rotating the nose wheel in case of taxi, etc. This is achieved by a plurality of arms in the transmission mechanism, which rotate relative to the parts connected to the air vehicle and/or to each other. When a force value greater than or equal to the predetermined threshold value is transmitted from the first connecting element to the transmission mechanism, it is transmitted to the second connecting element with almost the same force value. In case a force greater than or equal to the predetermined threshold value is applied, the ratio of the force input by the input element to the force output by the output element is equal to or close to one.

In an embodiment of the invention, the steering system comprises the transmission mechanism consisting of a first transmission mechanism and a second transmission mechanism. The force transmission from the input element to the output element is realized by the transmission mechanism. Since the arms in the first transmission mechanism and the second transmission mechanism have different lengths relative to each other and/or the mechanisms are positioned relative to each other, the force is transmitted at a different value or at the same value based on the threshold value predetermined by the user.

In an embodiment of the invention, the steering system comprises the first transmission mechanism and the second transmission mechanism in the form of a four-bar mechanism. The four-bar mechanism consists of simple movable connections that form a closed chain connection with four joints. Positions of the four-bar mechanisms relative to each other can change the transmitted force. Lengths, positions and alignment of the bars in the first transmission mechanism and the second transmission mechanism can make the force input to the mechanism and the force output by the mechanism different. In the four-bar mechanisms, one point is stationary and fixed to the air vehicle, wherein three arms are provided to form a closed loop.

In an embodiment of the invention, the steering system comprises the first transmission mechanism consisting of a first arm with an “L” form, one end of which is connected to the first connecting element, wherein the first arm transmits the force received from the first connecting element to the second arm, so that the transmission mechanism is provided with the force; a second arm with an "I" form, one end of which is connected to the first arm so as to be activated by the movement of the first arm; a third arm which is connected to the second arm on one end and transmits the force received from the second arm to the other end by rotating from the point where it is attached to the air vehicle. The first transmission mechanism consists of three arms and is fixed to the air vehicle from one point. In case of less force reaches the transmission mechanism than the predetermined threshold value, it decreases the force by increasing the movement received from the input element by means of the first connecting element, and transmits it to the second transmission mechanism.

In an embodiment of the invention, the steering system comprises a second transmission mechanism consisting of a fourth arm which is connected on one end to the third arm and transmits the force received from the third arm to a fifth arm; a fifth arm, one end of which is connected to the fourth arm and the other end to the second connecting element, and which rotates around an axis, to which it is connected between its two ends, to transmit the force received from the fourth arm to the output element by means of the second connecting element to which the other end thereof is connected; a sixth arm connected on one end to the fifth arm and on the other end to the air vehicle, and which can rotate in an area where it is connected, thus allowing the movement of the fifth arm. The second transmission mechanism consists of three arms and is fixed to the air vehicle from one point. The second transmission mechanism transmits the force received from the first four-bar mechanism to the second connecting element with the final precision output desired by the user.

In an embodiment of the invention, the steering system comprises the first connecting element that extends along its length and makes a linear movement along the direction it extends; and the second connecting element that extends along its length and makes a linear movement along the direction it extends. The first connecting element and the second connecting element extend substantially parallel to each other. In the transmission mechanism, the output force can be low compared to the input force, so that a precise output can be obtained. The arms in the transmission mechanism transmit the movement by rotating according to the connection points they are connected to the mechanism and/or to each other. The first connecting element and the second connecting element move linearly parallel to each other throughout the movement.

In an embodiment of the invention, the steering system comprises the fourth arm, which has a curved form. In this way, the fourth arm can easily rotate and provide force transmission. In an embodiment of the invention, the steering system comprises the fourth arm integral with the third arm. Thus, the third arm and the fourth arm simultaneously rotate on the connection point. By connecting the third arm and the fourth arm, the first transmission mechanism and the second transmission mechanism are interconnected. With the movement transferred from the third arm to the fourth arm, the force that is reduced or remained the same in the first transmission mechanism based on the threshold value, is transmitted to the second transmission mechanism. The third arm and the fourth arm can move as a single piece, so that they perform the force transmission between the first transmission mechanism and the second transmission mechanism by making simultaneous rotational movements.

In an embodiment of the invention, the steering system comprises the fourth arm, which has a concave form compared to the third arm. Therefore, the fourth arm transmits the force between the third arm and the fifth arm based on the predetermined threshold value. The fourth arm, which has a concave form, rotates more easily and transmits force from the first transmission mechanism to the second transmission mechanism.

In an embodiment of the invention, the steering system comprises the sixth arm, which is partially "C" shaped. The sixth arm is connected to the middle of the fifth arm on one end and to the air vehicle on the other end. In this way, it is possible for the fifth arm to transmit the force to the output element by making a rotational movement.

In an embodiment of the invention, the steering system comprises the first arm which is connected to the air vehicle almost on its mid-point and can rotate around the point of connection. The first arm has an "L" form. The force transmitted to the transmission mechanism by the first connecting element first triggers the first arm. Thus, the transmission mechanism is actuated by the first arm.

In an embodiment of the invention, the steering system comprises the input element which is a pedal; and the output element which is a hydraulic valve. The nose wheel steering system is driven by the hydraulic power of the air vehicle. If the nose wheel steering system is activated by the pilot, the air vehicle sends hydraulic pressure to the nose wheel steering system. In this case, the nose wheels are actively rotated with each pedal movement. As the hydraulic valve moves linearly and changes its position, it sends hydraulic fluid to different regions. Therefore, rotation of the nose wheels is ensured.

In an embodiment of the invention, the steering system comprises the transmission mechanism consisting of a gear mechanism and a third transmission mechanism. The relative lengths and/or relative positions of the gear mechanism and the third transmission mechanism determine the final movement output by the output element. If the amount of force applied by the pilot is less than the threshold value predetermined by the user, less force reaches the second connecting element than the force transmitted by the first connecting element. The second connecting element transmits the force to the output element by moving linearly in the direction it extends longitudinally. When the force is greater than or equal to the predetermined threshold value, the force equal to the force transmitted by the first connecting element is transmitted to the output element by the second connecting element. The force received from the first connecting element is transmitted to the third transmission mechanism via the gear mechanism. The force received from the third transmission mechanism is transmitted to the output element by means of the second connecting element.

In an embodiment of the invention, the steering system comprises a first gear rotatable within an angle range predetermined by the user, thus transmitting the force received from the first connecting element; and a second gear that transmits the force received from the first gear to the third transmission mechanism to which the other end thereof is connected, wherein the first gear and the second gear are provided in the gear mechanism.

In an embodiment of the invention, the steering system comprises the transmission mechanism used in a landing gear of air vehicle, which enables the wheels to be steered.

The steering system realized to achieve the object of the present invention is illustrated in the attached drawings, in which:

Figure 1 is a schematic view of a steering system.

Figure 2 is a schematic view of a transmission mechanism.

Figure 3 is a schematic view of the first transmission mechanism. Figure 4 is a schematic view of the second transmission mechanism.

Figure 5 is a schematic view of the gear mechanism and third transmission mechanism.

All the parts illustrated in figures are individually assigned a reference numeral and the corresponding terms of these numbers are listed below:

1. Steering system

2. Input element

3. Output element

4. Transmission mechanism

401. First transmission mechanism

402. Second transmission mechanism

403. Gear mechanism

404. Third transmission mechanism

5. First connecting element

6. Second connecting element

7. Arm

701. First arm

702. Second arm

703. Third arm

704. Fourth arm

705. Fifth arm

706. Sixth arm

8. First gear

9. Second gear

The steering system (1) comprises an input element (2) provided in an air vehicle, which provides a force for movement energy; an output element (3) which performs a movement requested by the user using the force applied by the input element (2); a transmission mechanism (4) located between the input element (2) and the output element (3), which transmits the force received from the input element (2) to the output element (3), thus enabling the movement desired by the pilot to be transmitted; a first connecting element (5) which connects the input element (2) and the transmission mechanism (4); a second connecting element (6) which connects the transmission mechanism (4) and the output element (3); at least one arm (7) located on the transmission mechanism (4) (Figure 1).

The steering system (1) according to the invention comprises the first connecting element (5) moving linearly in a direction it extends longitudinally, so as to transmit the force provided by the input element (2); the second connecting element (6) which triggers the output element (3) with less force than the force transmitted by the first connecting element (5) if an amount of force applied by the pilot is less than a threshold value predetermined by the user, and which moves linearly in a direction it extends longitudinally, so as to transmit the force to the output element (3); the second connecting element (6) which triggers the output element (3) with a force substantially equal to the force transmitted by the first connecting element (5), if the force is greater than or equal to the predetermined threshold value; the transmission mechanism (4) which has a plurality of arms (7), and transmits the force transmitted from the first connecting element (5) to the second connecting element (6) based on the threshold value when the plurality of arms (7) rotate around the connection points and/or each other (Figure 2, Figure 3, Figure 4).

The steering system (1) is used to steer air vehicles. The input element (2) provides a force input to generate movement energy. The force applied through the input element (2) is transmitted to the transmission mechanism (4) via the first connecting element (5). The transmission mechanism (4) is located between the input element (2) and the output element (3). It transfers the force received from the input element (2) via the first connecting element (5) to the output element (3) by means of the second connecting element (6). At least one arm (7) is provided on the transmission mechanism (4). Thanks to the movement of the arm (7), the transmission mechanism (4) transmits the force. In this way, the movement requested by the user is performed on the output element (3).

A force input is provided to the input element (2) by the pilot. The first connecting element (5) transmits the force provided by the input element (2) to the transmission mechanism (4) by moving linearly along the direction it extends. When the applied force is less than the threshold value predetermined by the user, it is transmitted to the second connecting element (6) with a reduced amount as a result of the rotational movements of a plurality of arms (7) provided in the transmission mechanism (4), around the connection points to the air vehicle and/or around each other. Thus, the second connecting element (6) triggers the output element (3) with less force than the force provided by the input element (2). Therefore, the desired precise output is provided. When a force value greater than or equal to the predetermined threshold value is transmitted from the first connecting element (5) to the transmission mechanism (4), it is transmitted to the second connecting element (6) substantially at the same force value. In this case, the force provided by the input element (2) and the force reaching the output element (3) and performing the final movement are equal to each other.

In an embodiment of the invention, the steering system (1) comprises the transmission mechanism (4) consisting of a first transmission mechanism (401) and a second transmission mechanism (402), wherein the first transmission mechanism (401) and the second transmission mechanism (402) have different lengths relative to each other and/or at varying positions to transmit force from the input element (2) to the output element (3), thus allowing the force to be changed based on the threshold value predetermined by the user. The transmission mechanism (4) consists of the first transmission mechanism (401) and the second transmission mechanism (402). Thanks to the different lengths of the plurality of arms (7) in the first transmission mechanism (401) and the second transmission mechanism (402) relative to each other and/or positions of the first transmission mechanism (401) and the second transmission mechanism (402) relative to each other, the force is transmitted at a different value by changing or at the same value, based on the threshold value predetermined by the user. Lengths, positions and alignments of the plurality of arms (7) in the first transmission mechanism (401) and the second transmission mechanism (402) determine the movement that will take place in the output element (3).

In an embodiment of the invention, the steering system (1) comprises the first transmission mechanism (401) and the second transmission mechanism (402), which are in the form of a four-bar mechanism. Positions of the first transmission mechanism (401) and the second transmission mechanism (402), which are in the form of four-bar mechanisms, can change the transmitted force. In an embodiment of the invention, the steering system (1) comprises the first transmission mechanism (401) consisting of a first arm (701) with an “L” form, one end of which is connected to the first connecting element (5), wherein the first arm (701) provides force input to the transmission mechanism (4) by transmitting the force received from the first connecting element (5) to the other end; a second arm (702) with an "I" form, one end of which is connected to the other end of the first arm (701) so as to be activated by the movement of the first arm (701); a third arm (703), one end of which is connected to the other end of the second arm (702), and which transmits the force received from the second arm (702) to the other end by rotating at the point where it is connected to the air vehicle. The first transmission mechanism (401) consists of the first arm (701), the second arm (702) and the third arm (703). When a force value less than the predetermined threshold value is applied by the user, the force is decreased by increasing the movement in the first transmission mechanism (401). In this way, a precise output is obtained.

In an embodiment of the invention, the steering system (1) comprises a second transmission mechanism (402) consisting of a fourth arm (704) which is connected on one end to the third arm (703) and transmits the force received from the third arm (703); a fifth arm (705), one end of which is connected to the fourth arm (704) and the other end to the second connecting element (6), wherein the fifth arm (705) rotates around an axis, to which it is connected between its two ends, to transmit the force received from the fourth arm (704) to the output element (3) by means of the second connecting element (6) to which the other end of the fifth arm (705) is connected; a sixth arm (706) connected on one end to the fifth arm (705) and on the other end to the air vehicle, and which can rotate in an area where it is connected, thus allowing the movement of the fifth arm (705). The second transmission mechanism (402) consists of the fourth arm (704), the fifth arm (705) and the sixth arm (706). Force is transferred from the first transmission mechanism (401) to the second transmission mechanism (402).

In an embodiment of the invention, the steering system (1) comprises the first connecting element (5) which extends longitudinally and makes a linear movement along the direction it extends; the second connecting element (6) which extends longitudinally and makes a linear movement along the direction it extends, wherein the first connecting element (5) and the second connecting element (6) extend substantially parallel to each other. The first connecting element (5) and the second connecting element (6) extend almost parallel to each other. The plurality of arms (7) in the transmission mechanism (4) transmits the movement by making rotational movements relative to the connection points they are connected to the transmission mechanism (4) and/or to each other. The first connecting element (5) and the second connecting element (6) move linearly parallel to each other throughout the movement.

In an embodiment of the invention, the steering system (1) comprises the fourth arm

(704), which has a curved form. In this way, the fourth arm (704) can easily rotate and provide force transmission.

In an embodiment of the invention, the steering system (1) comprises the fourth arm (704) integral with the third arm (703), thus rotating simultaneously with the third arm (703) on the connection point. By connecting the third arm (703) and the fourth arm (704), the first transmission mechanism (401) and the second transmission mechanism (402) are interconnected. The third arm (703) and the fourth arm (704) can move as a single piece, so that they perform the force transmission between the first transmission mechanism

(401) and the second transmission mechanism (402) by making simultaneous rotational movements.

In an embodiment of the invention, the steering system (1) comprises the fourth arm (704) which has a concave form compared to the third arm (703), thus transmitting the force between the third arm (703) and the fifth arm (705) based on the predetermined threshold value. The fourth arm (704), which has a concave form, rotates more easily and transmits force from the first transmission mechanism (401) to the second transmission mechanism

(402).

In an embodiment of the invention, the steering system (1) comprises the sixth arm (706) with a partially "C" form, which is connected substantially to the middle of the fifth arm

(705) on one end and to the air vehicle on the other end, thus allowing the fifth arm (705) to transmit the force to the output element (3) by making a rotational movement. In an embodiment of the invention, the steering system (1) comprises the first arm (701) with an “L” form, which is connected to the air vehicle substantially on its mid-point and is rotatable around this connection point. The transmission mechanism (4) is actuated by the first arm (701).

In an embodiment of the invention, the steering system (1) comprises the input element (2) which is a pedal; and the output element (3) which is a hydraulic valve. If the steering system (1) is activated by the pilot, the air vehicle sends hydraulic pressure to the steering system (1). In this case, nose wheels are actively rotated with each movement of the input element (2). As the output element (3) moves and changes its position, it sends hydraulic fluid to different regions. Therefore, rotation of the nose wheels is ensured.

In an embodiment of the invention, the steering system (1) comprises the second connecting element (6) which consists of a gear mechanism (403) and a third transmission mechanism (404), wherein if an amount of force applied by the pilot is less than a threshold value predetermined by the user, the second connecting element (6) triggers the output element (3) with less force than the force transmitted by the first connecting element (5), based on lengths and/or positions of the gear mechanism (403) and the third transmission mechanism (404) relative to each other, wherein the second connecting element (6) moves linearly in a direction it extends longitudinally, so as to transmit the force to the output element (3), wherein the second connection element (6) triggers the output element (3) with a force substantially equal to the force transmitted by the first connecting element (5), if the force is greater than or equal to the predetermined threshold value. The force received from the first connecting element (5) is transmitted to the third transmission mechanism (404) via the gear mechanism (403). The force received from the third transmission mechanism (404) is transmitted to the output element (3) via the second connecting element (6) (Figure 5).

In an embodiment of the invention, the steering system (1) comprises a first gear (8) rotatable within an angle range predetermined by the user, thus transmitting the force received from the first connecting element (5); and a second gear (9) that transmits the force received from the first gear (8) to the third transmission mechanism (404) to which the other end thereof is connected, wherein the first gear (8) and the second gear (9) are provided in the gear mechanism (403).

In an embodiment of the invention, the steering system (1) comprises the transmission mechanism (4) used in a landing gear of air vehicle, which enables the wheels to be steered.