Aerodynamic Body With Internal Actuating Drives

The present invention pertains to an aerodynamic body with internal actuating drives for generating variable arches.

An aerodynamic body is already known from U.S. Pat. No. 4,247,066, in which two beams, that can be adjusted in relation to one another in an articulated manner with threaded rods, are arranged in each segment. As a result of this a variable arch can be generated. The elastic profile skin slides on the beams and is also bent during their adjustment. The actuating drives used here require a considerable mechanical effort in terms of beams, threaded rods and ball joints.

The primary object of the present invention is to design an aerodynamic body of the type described in the introduction in a simpler and more reliably functioning form.

According to the invention, an aerodynamic body is provided with internal actuating drives for generating variable arches. At least one actuator is provided as an actuating drive which acts on an upper profile shell with a working piston and on a lower profile shell with a working piston, acting in the opposite direction. The profile shells are arranged displaceably in relation to one another.

One actuator is preferably arranged per body segment in the vicinity of the rear edge. The profile shells are preferably able to slide on one another by means of dovetail guides.

In the space before said actuator, the profile shells may be completely or partially connected to foam material, wherein a said space, which is mostly curved during the arching of the segment, is free from foam material.

To support the one actuator at the rear edges of a segment, two additional actuators, which are mutually connected to the said profile shells and to a front spar, are preferably provided in a space in the middle of said segment.

The profile shape of an aerodynamic body can be adjusted continuously by actuators with a lower working energy by means of the actuating drives according to the present invention. The profile shells are subjected to bending and absorb only a small amount of elastic energy because of their geometric shape. Thus, only a small amount of adjusting energy is to be generated with the actuators, which also absorb the longitudinal forces. The actuators are preferably arranged in the vicinity of the rear edge in each segment of the aerodynamic body. The profile shells can slide on one another by means of dovetail guides, which absorb the lateral forces.

To achieve a high inherent stability, the profile shells in the space between the profile shells before the actuator are completely or partially connected to foam material, which is subjected to shear during the adjustment. Areas of high shear deformation due to the arch of the aerodynamic body may be kept free from foam material in order to avoid the generation of excessive elastic forces and material failure. If necessary, the profile shells may be reinforced or be stiffened with stringers in this area in order the prevent an unacceptable bulging out at right angles to the chord of the profile of the body under air load. In the case of very large and rigid aerodynamic bodies, two additional actuators, which cooperate in generating the arch, may also be arranged in the space between the actuator at the rear edge and a spar arranged in the front half of the body, which are mutually connected to the profile shells and to the spar.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.

In the drawings:

FIG. 1 is a sectional view of the rear edge of a segment of an aerodynamic body with a built-in actuator;

FIG. 2 is an entire segment of the body according to FIG. 1 with upwardly arched rear edge;

FIG. 3 is the segment according to FIG. 2 with downwardly arched rear edge; and

FIG. 4 is a segment of an aerodynamic body, in which two additional actuators are arranged in the middle.

Referring to the drawings in particular, the invention comprises an upper profile shell 2 and a lower profile shell 3, which are able to slide on one another by means of dovetail guides 4 and 5. The profile shells are present in the rear edge of a segment 1 of an aerodynamic body. The upper profile shell 2 includes an upper aerodynamic body skin. The lower profile shell 3 includes a lower aerodynamic body skin. By an attachment 3a, the lower profile shell 3 forms a hollow space 6 with the upper profile shell 2. An actuator 7 is mounted in this hollow space 6. At both ends, the actuator 7 has working pistons 8 and 9, which can be extended, e.g., hydraulically, and they engage openings 11 and 12 of the profile shells 3 and 2. The opening 11 is formed in a lower profile shell portion of lower profile shell 3 extending away from the lower aerodynamic body skin (e.g., into the interior of the connected shells). The opening 12 is formed in an upper profile shell portion of upper profile shell 2 extending away from the upper aerodynamic body skin (e.g., into the interior of the connected shells). When the working piston 9 is extended, as is shown in FIG. 2, the profile shell 2 is pressed upward, as a result of which the aerodynamic body 1 arches upward. When the working piston 8 is being extended, it acts on the profile shell 3, as a result of which the segment 1 of the aerodynamic body arches downward, corresponding to FIG. 3. The profile shells 2 and 3 slide on one another in both cases by means of the dovetail guides, which also act as supports at the same time.

FIGS. 2 and 3 also show that supports 13 through 17 made of foam material, which are subjected to shear during the adjustment of the profile shells 2 and 3, are arranged in the space between the profile shells 2 and 3 before the actuators 7. The space 18 of high shearing stress behind the actuator 7 is advantageously kept free. The profile shells 2 and 3 are connected to a spar 19 in the front part of the segment 1.

FIG. 4 shows a segment 20 of another aerodynamic body, in which two additional actuators 21 and 22 are also built in in the space 23 in the middle of the segment 20, besides the actuator 7 at the rear edge. The actuators 21 and 22 are supported on one side at the spar 19 with rods 24 and 25 and have working pistons 26 and 27 of increased length, with which they are able to act on the profile shells 2 and 3 to generate the desired arch of the profile. The segment 20 is also provided with a reinforcement 28.

While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.