Elastic joints having a torsion stop and use of such joints in vibration absorbers

Abstract

Novel elastic torsion stop components based on multilayer elastomer metal elements in cylindrical, conical, or spherical shape. The elastic torsion stop components are particularly suitable for use as maintenance-free and low-wear joints having a large angular spread, for example in vibration absorbers, such as in pendulum vibration absorbers for wind turbines.

Claims

1. An elastic torsion joint of a pendulum vibration absorber, which is capable of providing multi-stage deflection angles of at least 50° deflection, the elastic torsion joint comprising: (i) an inner fixed joint ball, (ii) an elastic layer element which can move around the inner fixed joint ball and which is composed of a plurality of concentric annular elastic layers that are separated from one another by intermediate concentric annular metal sheets, and (iii) a torsion stop, wherein (iv) the elastic layer element (2) substantially has a shape of a spherical half-shell, to the center of the flat side of which said inner fixed joint ball (2.7) is attached together with the torsion stop (2.4), which is a stop ring, (v) the inner fixed joint ball (2.7) is rigidly connected to the innermost elastic layer of the layer element such that, when the layer element moves relative to the inner fixed joint ball, said innermost elastic layer is deformed the most of all the layers, and the joint ball is functionally operatively connected to the torsion stop ring, (vi) the torsion stop ring (2.4) and the layer element are designed such that, the torsion stop ring strikes by pressing against the innermost intermediate metal sheet of the layer element (2) closest to the joint ball during a cardanic movement of the layer element (2) and the inner fixed joint ball (2.7) relative to one another by at least a first defined deflection angle (2.20), thus the adjacent outward-positioned concentric annular elastic layer of the elastic layer element (2) being unable to undergo any further deformation, (vii) the torsion stop ring (2.4) has a profile structure that corresponds to the at least first defined deflection angle on the side facing the annular intermediate metal sheets, and strikes against the annular long edge, facing the torsion stop, of the relevant annular intermediate metal sheet that protrudes from the spherical half-shell, (viii) the concentric annular metal sheets are provided with circumferential stop elements (2.22) at each of the points against which the torsion stop ring (2.4) presses during deflection, and (ix) the elastic layer element (2) comprises at least three elastic layers, wherein the inner concentric annular elastic layers of the elastic layer element (2) are thinner than the outer layers provided that stiffness of the elastomer material in the elastic layers is the same or similar.

2. The elastic torsion joint according to claim 1, wherein the profile structure of the torsion stop ring (2.4) corresponds to a second defined deflection angle (2.21) of the joint, and the torsion stop ring strikes against the nearest outward-located concentric annular intermediate metal sheets.

3. The elastic torsion joint according to claim 2, wherein profile structure of the torsion stop ring (2.4) corresponds to a further defined deflection angle of the joint, and the torsion stop strikes concentric annular intermediate metal sheets located further outward in stages according to further deflection angles.

4. A Cardan joint, wherein the Cardan joint comprises an elastic torsion joint according to claim 1.

5. The Cardan joint according to claim 4, wherein the Cardan joint additionally comprises eddy-current-operated damping elements (6.6).

6. The Cardan joint according to claim 4, wherein the Cardan joint comprises a transmission gear (6.2).

7. A vibration absorber comprising an elastic torsion joint according to claim 1.

8. A vibration absorber comprising a Cardan joint according to claim 4.

9. A vibration absorber, wherein the vibration absorber comprises a pendulum which is connected via a control link lever (1.8) to an elastic torsion joint according to claim 1.

10. A vibration absorber, wherein the vibration absorber comprises a pendulum which is connected via a control link lever (1.8) to a Cardan joint according to claim 4.

11. A wind turbine, wherein the wind turbine comprises an elastic torsion joint according to claim 1.

12. A wind turbine, wherein the wind turbine comprises a Cardan joint according to claim 4.

13. A wind turbine, wherein the wind turbine comprises a pendulum vibration absorber which is provided with the elastic torsion joint according to claim 1.

14. An elastic torsion joint of a pendulum vibration absorber, which is capable of providing multi-stage deflection angles of at least 50° deflection, the elastic torsion joint comprising: (i) an inner fixed joint ball, (ii) an elastic layer element which can move around the inner fixed joint ball and which is composed of a plurality of concentric annular elastic layers that are separated from one another by intermediate concentric annular metal sheets, and (iii) a torsion stop, wherein (iv) the elastic layer element (2) substantially has a shape of a spherical half-shell, to the center of the flat side of which said inner fixed joint ball (2.7) is attached together with the torsion stop (2.4), which is a stop ring, (v) the inner fixed joint ball (2.7) is rigidly connected to the innermost elastic layer of the layer element such that, when the layer element moves relative to the inner fixed joint ball, said innermost elastic layer is deformed the most of all the layers, and the joint ball is functionally operatively connected to the torsion stop ring (2.4), (vi) the torsion stop ring (2.4) and the layer element are designed such that, the torsion stop ring strikes by pressing against the innermost intermediate metal sheet of the layer element (2) closest to the joint ball during a cardanic movement of the layer element (2) and the inner fixed joint ball (2.7) relative to one another by at least a first defined deflection angle (2.20), thus the adjacent outward-positioned concentric annular elastic layer of the elastic layer element (2) being unable to undergo any further deformation, (vii) the torsion stop ring (2.4) has a profile structure that corresponds to the at least first defined deflection angle on the side facing the annular intermediate metal sheets, and strikes against the annular long edge, facing the torsion stop, of the relevant annular intermediate metal sheet that protrudes from the spherical half-shell, and (viii) the elastic layer element (2) comprises at least two elastic layers, wherein the inner concentric annular elastic layers of the elastic layer element (2) are thinner than the outer layers provided that stiffness of the elastomer material in the elastic layers is the same or similar.

15. The elastic torsion joint according to claim 14, wherein the concentric annular metal sheets are provided with circumferential stop elements (2.22) at each of the points against which the torsion stop ring (2.4) presses during deflection.

16. The elastic torsion joint according to claim 14, wherein the elastic layer element (2) comprises at least three elastic layers.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1A and 1B show a bushing according to the invention having a cylindrical layer element and stop function;

(2) FIG. 2 is a perspective view showing a control link lever for large angular deflection, which lever has a corresponding component according to FIG. 1 in its eye;

(3) FIG. 3 is a view showing a corresponding cylindrical layer element, as in FIG. 1, but in this case all of the protruding intermediate sheets in the movement space of the stop are substantially the same length or protrude equally far into said cut-out;

(4) FIG. 4 shows a bushing-shaped layer element, corresponding to FIG. 1, but which has intermediate sheets that protrude on both flat sides of the bushing and comprise cut-outs, each for a torsion stop;

(5) FIG. 5 shows various views of elastomer Cardan joints and double Cardan joints which are provided with the bushings, according to the invention from FIGS. 1-4, and are therefore ideally suited for large deflections;

(6) FIG. 6 shows the second basic embodiment of the invention, namely a ball joint having a spherical joint body, which has a cut-out in the center for a fixed joint ball which is rigidly connected to the innermost elastic layer and is moved or deformed during movement (deflection);

(7) FIG. 7 shows the application of two connected spherical joints, according to FIG. 6, to form a Cardan joint operating in one plane;

(8) FIGS. 8A and 8B shows the possible use of a Cardan joint, according to the invention according to FIGS. 6 and 7, with a pendulum absorber, as can typically be used in a wind turbine;

(9) FIG. 9 shows an elastic bearing according to the invention comprising a torsion stop, the elastic bearing being constructed from a conical base body having correspondingly shaped, rotationally symmetrical, conical elastomer layers and metal plates arranged alternately around the cone axis;

(10) FIGS. 10A and 10B are perspective views of a pendulum suspension which is fastened to a support structure;

(11) FIG. 11 shows the cardanic pendulum suspension of FIG. 10 in a plan view, in which the position and attachment of the elastic bearings according to the invention described here that comprise an elastic torsion stop are indicated at both ends of the two shafts of the Cardan joint, with said bearings, which are installed in corresponding brackets, only being indicated schematically; and

(12) FIG. 12 shows the cardanic pendulum suspension of FIG. 11, provided with conical elastomer bushings, according to the invention, comprising an elastic torsion stop, as shown in FIG. 9, for example.

DETAIL DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION

(13) FIGS. 1A and 1B show a bushing according to the invention having a cylindrical layer element and stop function. The bushing comprises intermediate sheets protruding on one side. A movement space for the torsion stop in the form of an angular segment is cut out from these protruding intermediate sheets. The intermediate sheets extend into the movement space by different lengths, with the innermost sheet extending further in, i.e. being relatively longer, than the second-innermost sheet, and so on. The resulting deflection angles for the torsion stop are indicated by (1.5) (innermost and smallest angle) and (1.6) (second-innermost and larger angle). The bushing comprises a prestressing window (1.7) in all layers.

(14) FIG. 2 shows a control link lever (1.8) for large angular deflection, which lever has a corresponding component according to FIG. 1 in its eye.

(15) FIG. 3 shows a corresponding cylindrical layer element as in FIG. 1, but in this case all of the protruding intermediate sheets in the movement space of the stop are substantially the same length or protrude equally far into said cut-out. The stop element (1.4) comprises correspondingly different beveled surfaces for striking against the relevant intermediate sheet, according to the desired deflection angle (1.5)(1.6).

(16) The figure shows, in detail, a double Cardan joint for the suspension of a transverse mass damper.

(17) FIG. 4 shows a bushing-shaped layer element (1) corresponding to FIG. 1, but which has intermediate sheets that protrude on both flat sides of the bushing and comprise cut-outs, each for a torsion stop (1.4). In the embodiments of FIGS. 1-4, the intermediate sheets 1.1 protrude further out than the elastomer layer 1.3 at least on one side; in principle, this extension can also be achieved on both ends of the bushing. The intermediate sheets 1.1 are provided with a cut-out 1.2.1 and 1.2.2 which releases a particular angle. At the same time, a torsion stop 1.4 is connected to the axle. After a particular angle 1.5, it carries along the inner sheet on the stop 1.2.1 such that no further deformation of the inner layer occurs. At an even larger angle 1.6, the second sheet 1.2.2 is carried along by the torsion stop 1.4. FIG. 1 shows a component comprising three layers in which two sheets are moved by the torsion stop 1.4. In principle, any number of layers having the relevant stop function can be arranged.

(18) FIG. 5 shows various views of elastomer Cardan joints and double Cardan joints which are provided with the bushings according to the invention from FIGS. 1-4 and are therefore ideally suited for large deflections.

(19) FIG. 6 shows the second basic embodiment of the invention, namely a ball joint having a spherical joint body, which has a cut-out in the center for a fixed joint ball (2.7) which is rigidly connected to the innermost elastic layer and is moved or deformed during movement (deflection). The possible total deflection angle is composed of the angles (2.20) and (2.21) and is achieved in this specific case by two stages in the profile of the stop (2.4). Circumferential stop elements (2.22) attached to the end part of the respective annular intermediate sheets increase the accuracy of the strike between the stop element (2.4) and the intermediate sheets of the spherical layer element.

(20) The ball joint according to the invention consists of a plurality of hemispherical elastomer layers (2.3). These are stacked one on top of the other and connected to one another by attached hemispherical sheets (2.1). The outer bell (2.5) rotates around the inner ball (2.7).

(21) Since the circumference of the inner ball is significantly smaller than that of the outer bell, the elastomer would rotate almost only in the inner region. In the outer region there would only be elastic material that does not take part in the deformation. This is prevented by the spherical intermediate sheets (2.1) each co-rotating in stages according to a particular angle and thus experiencing only a limited torsional movement. The stop ring (2.4) in this case rotates together with the inner ball (2.7) and, after a certain angle, rests against the sheet edge (2.2.1), and is further rotated together with said edge. After a further angle, the stop (2.2.2) comes into engagement such that ultimately only the outermost layer can deform. The ball joint according to the invention can be used wherever a large angular movement has to take place in the space. By comparison with the bushing comprising a Cardan joint, the ball joint does not need a cardanic arrangement to allow spatial movement.

(22) FIG. 7 shows the application of two connected spherical joints according to FIG. 6 to form a Cardan joint operating in one plane.

(23) FIGS. 8A and 8B show the possible use of a Cardan joint according to the invention according to FIGS. 6 and 7 with a pendulum absorber, as can typically be used in a wind turbine. The joints are integrated in pendulum rods (3), and the joints are connected at their upper end to the supporting structure of the system (e.g. the tower of the wind turbine) and at the other end to the pendulum mass (5). The mass (5) can thus swing freely transversely in the horizontal plane by a large deflection angle.

(24) FIG. 9 shows an elastic bearing according to the invention comprising a torsion stop, the elastic bearing being constructed from a conical base body having correspondingly shaped, rotationally symmetrical, conical elastomer layers (1.3) and metal plates (1.1) arranged alternately around the cone axis, the cone angle (1.15) being formed by the longitudinal axis and the conical surfaces inclined thereto. In addition to the actual stop element (1.4), the inner and outer stop angles (1.5) (1.6) can also be seen here.

(25) FIG. 10(A) is a perspective view of a pendulum suspension (6) which is fastened to a support structure (6.5). The pendulum suspension comprises a twin-shaft Cardan joint or universal joint (6.1), as well as a transmission gear (6.2) and a damping element (6.6) at one end of each of the two shafts of the joint. The pendulum rod (6.8) at the lower end of the suspension (6.7) is only shown in part. The two damping elements (6.6) on the shafts can be provided with rotational masses (6.6.1) (not shown separately in this case), which masses are optional and can be omitted if no additional frequency setting is desired or necessary. The elastic bearings according to the invention comprising an elastic torsion stop (6.4), in the form of the described cylindrical elastomer bushings, the spherical half-shells or the conical elastomer bushings, are not shown.

(26) The damping units (6.6) are preferably operated by means of eddy currents, and comprise a preferably rotationally symmetrical conductor disk and a likewise preferably rotationally symmetrical disk that is provided with permanent magnets or electromagnets and is made of steel, ceramic or plastics material, for example. Both disks are in this case arranged opposite one another and separated from one another by an air gap, and move relative to one another around the shaft, triggered by a pendulum movement, thus creating an eddy current that generates a force counter to the force moving the pendulum, so that the pendulum movement is damped or decelerated.

(27) Furthermore, the eddy current damping unit (6.6) can additionally have an optionally variable adjustable rotational mass, as described in more detail in WO 2019/029839. As a result, and additionally by using disks having different diameters in order to increase the speed of rotation of the regions of the disks comprising the magnets, the natural frequency of the vibration system can be influenced or the vibration system can be adapted to the vibrational conditions.

(28) FIG. 10(B) shows the Cardan joint from (A) from a different perspective as a component of the pendulum suspension, comprising elastomer bushings (19)(19.1) and torque supports (23), an inner lever (23.1), an outer lever (23.2), an elastic stop (23.3) and torque supports having an idle angle (24), (inner lever 24.1), (outer lever 24.2), (elastic stop 24.3) and free movement angle (24.4).

(29) FIG. 11 shows the cardanic pendulum suspension of FIG. 10 in plan view, in which the position and attachment of the elastic bearings according to the invention described here that comprise an elastic torsion stop (1.4)(6.4) are indicated preferably at both ends of the two shafts of the Cardan joint, with said bearings, which are installed in corresponding brackets (6.9), only being indicated schematically. On the gear side, the shafts are also guided by a bracket (6.7).

(30) FIG. 12: shows the cardanic pendulum suspension of FIG. 11, provided with conical elastomer bushings (6.4.1) according to the invention comprising an elastic torsion stop (6.4), as shown in FIG. 9, for example.