DE588390C - Device for the automatic control of aircraft by means of a wind vane - Google Patents

Description

It is already known the rudder of an airplane to steer automatically by the relative wind by means of a wind vane, which by a suitable motion transmission device connected to the rudder to be controlled is.

The wind vane can in particular be attached to a four-bar hinge, one side of which is connected to the aircraft and with the help of a control lever or a similar device can be angularly adjusted.

The invention relates to improving an aerodynamic control device for aircraft with wind vanes of the type mentioned above.

The improvement consists essentially in the fact that, besides one, the one with the wind vane connected quadrilateral pivoting control member provided a control device is which in which the wind vane with the to

ao controlling rudder connecting motion transmission device is switched on and the allows to change the relative position of the rudder with respect to the wind vane.

This control device allows on the one hand to eliminate the uncertainty related to the correspondence of the angle of the rudder with the angle of inclination of the plane connected side of the articulated square of the wind vane as a result of play or as a result of There is a response from the controls and, on the other hand, the angle of the rudder to the flight conditions, for example trim changes, adapt, the angle of attack and as a result the angle of adjustment of the side of the articulated square of the wind vane connected to the aircraft remains constant.

The drawing shows an example of an application of a control device according to FIG Invention shown, namely Fig. Ι a side view of an aircraft control device with the control device according to the invention, Fig. 2 a part of the wind vane in Section and Fig. 3 the arrangement of the controller.

In the figures, the main wing of the aircraft is denoted by W, the rudder by G and the wind vane by P. The wind vane P is attached to the wing W by means of a pivot axis A and a support frame S. The wind vane can be adjusted by means of the handlebar b and the control lever L, both of which act on the side of the quadrangle that is connected to the aircraft.

The rod t of the wind vane is rigidly connected to a gear ^ arranged on the axis A. This gearwheel ^ ₁ meshes with a gearwheel ft ₂ , which is rigidly connected to a gearwheel f> _{a which} meshes with the gearwheel pi. The gear wheel p _A carries an arm d ' which moves a link β and the rudder G via two levers g and g _x.

. If the relative wind, which was moving in the direction of the line x,% ' , changes its direction of movement for any reason, the wind vane is swiveled up or down depending on whether the wind acts on the wind vane from above or below which swings the rudder in the opposite direction and brings the aircraft to its original angle of attack ίο.

The wind vane therefore works as an automatic compensation device. The angle of attack at which the flight is on this. Type is automatically regulated can be changed by changing the position of the side ^ _{1 of} the articulated square of the wind vane by means of the lever L and the handlebar δ. If the side t _{x of} the four-bar linkage is adjusted by an angle α by means of the lever L , the arm d is pivoted by the angle a ' and the rudder G is pivoted by a corresponding angle β via levers g, g _x and cables c, C ₁ pivoted so that the angle of attack of the aircraft changes. It is known that, in a particular aircraft, the relationship that exists between the pitch angle β of the rudder and the corresponding change in the angle of attack is generally non-linear.

Since the adjustment angle β of the rudder is proportional to the angle α , it follows that the angle β resulting from an angle adjustment α of the side Jf _{1 of} the wind vane will generally change the angle of attack of the aircraft by a value different from α. Das.genaue working of the device, however, requires that the change in the angle of attack resulting from a pivoting α of the rod t _{x of} the wind vane is exactly the same as the angle α. For this purpose, according to the invention, a control device to be operated by the pilot is switched into the motion transmission device connecting the arm d to the rudder G , which control device allows the relative positions of the rudder G and the arm i to be changed. This device makes it possible to correct the swiveling of the rudder G resulting from a swiveling about the angle a of the side t _{x of} the wind vane in such a way that the aforementioned adjustments cause a change in the angle of attack by an angle equal to α.

On the other hand, with regard to flight, a structure is not only determined by the arrangement of its surfaces, but also by the position of its center of gravity. But the position of this center of gravity depends essentially on the position of the load. This situation changes from one flight to another when ballast is dropped, even during one and the same flight. It follows from this that each position of the center of gravity would have to correspond to a value other than β for one and the same angle of attack.

The control device incorporated into the motion transmission device connecting the arm d to the rudder G also makes it possible to achieve this result.

Such a device, which can be switched on at H , is shown schematically in FIG.

Instead of being pulled directly from g to g _x , the cables c and C ₁ are guided over six pulleys q _x , q ₂ , q _s , q _b q ₅ , q _6. The rollers q _s , q _lt q ₅ , q _e are mounted on fixed axles. In contrast, the axes of the rollers q _x and ^ ₂ are attached to the two ends of a rack C , which can be moved up or down when a gear R rotates. The gear R is moved by a handwheel V , indicated by dashed lines, which the operator can turn.

It is clear that every shift of the rack C and the rollers q _ly q _% upwards a shortening of the effective part of the cable c and an extension of the effective part of the cable C ₁ and therefore also a change in the position of the arm i relative to the lever g _x results in. Conversely, a downward displacement of the rack C results in a lengthening and shortening of the effective part of the cables c and C ₁ in the opposite direction.

In this way, the rudder can be adjusted during the flight so that the flight is carried out at a desired angle of attack. This depends on the position of the lever L and the action of the gearbox, with the wind vane keeping everything in its central position when the wind is calm. ■ iqo

The control device H can be replaced by any equivalent mechanical device which enables the relative position of arm d and lever g _x to be changed arbitrarily during flight. For example, the length of the link e could be changed for the same purpose.

Claims (3)

Patent claims: i. Device for the automatic control of aircraft by means of a wind vane, which is attached to a four-bar linkage, the side of which is connected to the aircraft can be angularly adjusted, characterized by a control device (H) that connects the wind vane (P) with the rudder (G) connecting motion transmission device is switched on and through which the relative position of the rudder (G) to the wind vane can be changed. 2. Apparatus according to claim i, characterized in that a controller (H) acts on one (c) or the other (C ₁ ) cable of the double-transmission connecting line between the wind vane and the rudder controlled by it. 3. Device according to claim i and 2, characterized in that the controller Has rollers (q _x , q _z ) attached to the ends of a rack (C) over which the cables (c, C ₁ ) of the motion transmission device connecting the wind vane to the rudder run, the rack being transverse to the direction of movement of the cables by means of a handwheel can be moved. For this purpose 1 sheet of drawings ■ BERLIN PRINTED IN THE REICHSDRUCKEKEI