BG64591B1 - Propeller - Google Patents

Abstract

The propeller is designed to operate in fluid media, in particularly in aeronautics. It has the facility of changing the characteristics of the longitudinal section of its blades. It comprises a driving shaft (1) with pivotally suspended blades (5) with horizontal arms (6) in their bases. Each blade (5) has inner (7) and outer (8) fin interconnected in the peripheral section (11) of blade (5). Between fins (7 and 8) side clearances are provided. The radial ends of fins (7 and 8) have two-side roundings (9 and 10) along their lengths.

Description

Technical field

The invention relates to a propeller intended for use in fluid environments, in particular in aviation for helicopters and others.

BACKGROUND OF THE INVENTION

A propeller is known, consisting of a drive shaft with suspended blades by means of a horizontal, vertical and axial joint for each of them. The blades are monolithic and have basically horizontal arms connected by vertical bars with a tilting mechanism / 1 /.

The disadvantage of this solution is the monolithic design of the blades, allowing a slight change between radially spaced portions of the blade, which reduces the possibility of changing their characteristics. Another disadvantage is the large diameter of the propeller.

It is an object of the invention to provide a propeller capable of altering the characteristic of longitudinal portions of its blades.

SUMMARY OF THE INVENTION

The task is accomplished by a propeller comprising a drive shaft with hinged blades with horizontal arms at their base. According to the invention, each blade is made up of an inner and outer feather, connected to each other in the peripheral portion of the blade, on which the feathers are provided with lateral clearance, and the radial ends of the feathers are formed with corresponding roundings.

The inner and outer feathers are joined together by an elastic connection.

The inner and outer fins are connected to each other by a hinge joint, oriented transversely to the length of the blade, in the peripheral portion of which is provided a limiter of rotation of the inner pen.

The inner pen is arranged along the length of the outer blade of the blade, whose total length includes the length of the two feathers.

At the base of the blade is a pivotally connected hydraulic cylinder whose piston rod is pivotally connected to a rib from the inner pen.

An advantage of the invention is the ability to modify the characteristic of the longitudinal portions of the blades and to reduce the outer diameter of the propeller.

Explanation of the annexed figures

Figure 1 is a longitudinal section of the propeller;

Figure 2 is an A view of a propeller blade;

Figure 3 is a front view of a blade with a swivel between its feathers;

4 is a sectional view along B-B of FIG. 2 when the inner pen is turned;

Figure 5 is a front view of a blade in another embodiment;

6 is a sectional view along B-B of FIG. 2 at different angles of inclination of the blades of the blade;

Figure 7 is a longitudinal section view of a blade with serially directed feathers in one direction;

8 is a longitudinal sectional view of the blade of FIG. 7 with a double hinge between its feathers;

Figure 9 is a longitudinal section of a blade at the free end of which a second inner pen is connected at the inner end;

Figure 10 is a longitudinal section view of a blade controlling its inner pen.

Examples of carrying out the invention

The propeller is composed of a drive shaft 1 with horizontal blades 2, vertical 3 and axial 4 hinge blades 5 with horizontal arms 6 connected to a tilting mechanism 21 of a known type. Each blade 5 is composed of an inner pen 7 and a annular outer pen 8 connected to each other in the peripheral portion 11 of the blade 5. Side slots are provided between the feathers 7 and 8. The radial ends of the feathers 7 and 8 have corresponding rounds 9 and

10. In one embodiment shown in Figure 2, the inner 7 and outer 8 feathers are joined by an elastic link 13.

In another exemplary embodiment, shown in Figure 3, the inner 7 and the outer 8 of the pen are connected by a hinge 14, oriented transversely to the length of the blade 5. In the peripheral portion 11 of each blade 5 is provided a limiter 12 for the mutual rotation of the feathers 7 and 8. Alternatively, according to Figure 5, the inner pen 7 is disposed bilaterally with respect to the hinge 14, with a circular clearance between the two feathers 7 and 8.

In another embodiment shown in Figure 6, the angle of inclination of the inner pen 7 is different from the angle of inclination of the outer pen 8.

In another embodiment shown in Figure 7, the inner pen 7 is disposed along the outer pen 8 of the blade 5 whose total length includes the lengths of the two feathers 7 and 8.

In the embodiment shown in Figure 8, the hinge joint between the feathers 7 and 8 also has a second vertical hinge 15, located transversely to the first hinge 14.

In another embodiment shown in Figure 9, a second inner feather 20 is connected at the free end 23 of the inner feather 7. The second inner feather 20 is disposed in an opening of the inner feather 7, and is optionally tangential to it.

In another embodiment shown in Figure 10, the pivot 16 of the blade 5 is connected by a hinged hydraulic cylinder 17 whose piston rod 18 is connected via a second hinge 19 to a rib 22 of the inner pen 7. The hydraulic cylinder 17 is connected by a flexible conduit to the drive shaft. 1 and by means of a well-known collector of a hydraulic unit.

Use of the invention

As the drive shaft 1 rotates, the propeller blades 5 create a pulling force. The periodic change of the tilt angle of the blades 5 (from the tilting mechanism 21) causes the blades 5 to swing about their horizontal joints 2.14 and partly around the vertical joints 3. This allows for a change in the characteristic of the blade 5, when the mutual arrangement of the blades 7 changes and

8. The inner pen 7 swings relative to the outer 8 about the hinge joint 14. The inner pen 7 acts on the outer 8, reducing its swing amplitude. In the case of a swivel between the feathers 7 and 8, the swing angle of the inner feather 7 is bounded bilaterally by the stop 12. In the blades 5 of FIG. 1-6, the diameter of the propeller can be reduced as well as the inertia moment of the blades 5.

Forced rotation of the inner feathers 7 is carried out by the hydraulic cylinders 17, thereby changing the characteristic of the blade 5.

In positioning the inner pen 7 along the outer 8 according to FIG. 7, the length of the blades is increased. 5. Using the vertical (second) hinge 15, FIG. 8, the inner pen 7 can be rotated in two mutually perpendicular directions.

Claims (5)

Claims A propeller comprising a drive shaft with hinged blades with horizontal arms at their base, characterized in that each blade (5) consists of an inner feather (7) and an outer feather (8) connected thereto. in the peripheral portion (11) of the blade (5), between which the feathers (7 and 8) are provided with lateral grooves, the radial ends of the feathers (7 and 8) having longitudinal roundings (9 and 10) respectively. A propeller according to claim 1, characterized in that the inner (7) and outer (8) feathers are connected to each other by an elastic connection (13). A propeller according to claim 1, characterized in that the inner (7) and outer (8) feathers are interconnected by means of a hinge (14) oriented transversely to the length of the blade (5), such as in the peripheral portion (11) ) each blade (5) is provided with a rotation limiter (12) on the inner pen (7). A propeller according to claims 1 to 3, characterized in that the inner feather (7) is disposed along the outer feather (8) of the blade (5) whose total length includes the lengths of the two feathers (7 and 8) . A propeller according to claims 1, 3 and 4, characterized in that at the base (16) of the blade (5) is connected a hinged hydraulic cylinder (17), whose piston rod (18) is connected by a second hinge (19) to the inner pen (7). Attachment: 10 figures Literature