Torsional vibration isolation coupling

Abstract

The invention relates to a torsional vibration isolation coupling (1) having an axis of rotation (1a), comprising a first coupling part (2) as the input side of the coupling (1), a second coupling part (3) as the output side of the coupling (1), and a damping unit (4), characterized in that the damping unit (4) has at least one spring arrangement (10, 10 '), the spring arrangement is configured as a non-linear spring arrangement (10, 10 ') with a decreasing spring characteristic curve (13).

Description

Technical Field

[0001] The invention relates to a torsional vibration isolating coupling according to the preamble of claim 1 . Background Art

[0002] Torsionally-vibration-isolating couplings are used, for example, in stationary internal combustion engines.

[0003] Such stationary internal combustion engines are also known as so-called generator motors and are used in conjunction with a generator to generate electrical energy. Their application ranges from emergency power supply to providing electrical energy for ship drives. In this case, these internal combustion engines are usually operated with diesel or natural gas. Another area of ​​application is piston compressors.

[0004] In contrast to mobile passenger vehicle or truck drives, which are subjected to varying speeds and frequently changing loads during driving operation, these applications are characterized by predominantly stable operating points, at which the speed remains constant and the load torque is virtually constant.

[0005] The prior art mainly provides a torsional vibration isolation coupling with a linear spring characteristic curve for this purpose. In this case, the torsional vibration isolation torsion spring stiffness is usually determined according to the drive torque to be transmitted.

[0006] In this case, there are two requirements for the torsional vibration isolating coupling.

[0007] First and foremost, the first requirement is to transmit the static drive torque. The main task of this stable-running application is to provide an almost constant torque at a fixed speed. This torque acts on the drive train as a static load and must be transmitted by the coupling. Therefore, the torsional stiffness of the coupling must be correspondingly high in order to be able to transmit the static torque.

[0008] Secondly, torque fluctuations need to be isolated, that is, broadband vibration isolation is required.

[0009] With regard to the dynamic behavior of the drive train during operation of the internal combustion engine, the coupling must decouple the components connected to one another via the drive train (e.g. internal combustion engine / motor and generator or ship propeller) from disruptive influences (e.g. fluctuations in the drive torque or load torque). Therefore, a correspondingly low torsional stiffness of the coupling is necessary in order to achieve the widest possible vibration isolation of the coupling.

[0010] These two requirements lead to a conflict of objectives with regard to the optimum torsional rigidity of the coupling: On the one hand, this torsional rigidity should be high enough to transmit static torques, but at the same time should be as low as possible in order to isolate disruptive drive vibrations.

[0011] Since the main task of the drive train is to transmit static torque, a correspondingly high coupling stiffness is usually selected. These drive trains therefore have the disadvantage that additional components (e.g. torsional vibration dampers) are required to damp the undesired torque vibrations, or the components must be designed for increased torsional vibrations. This leads to additional costs and, as a rule, also to an increased space requirement due to the increased axial length of the entire drive train. In addition, the damping effect of these additional components is usually effective over a limited frequency or speed range. Summary of the invention

[0012] The object of the present invention is therefore to provide a torsional vibration isolating coupling which meets both requirements of transmitting static torque and simultaneously isolating the drive train over a wide band and which also eliminates or at least significantly reduces the disadvantages of increased structural space requirement and limited frequency or speed range.

[0013] This object is achieved by a torsional vibration isolating coupling having the features of claim 1 .

[0014] Therefore, a torsional vibration isolating coupling with a rotation axis comprises a first coupling part as the coupling input side, a second coupling part as the coupling output side, and a damping unit. The damping unit has at least one spring arrangement component, which is designed as a nonlinear spring arrangement component with a decreasing spring characteristic curve.

[0015] The torsional vibration isolating coupling having a damping unit comprising a nonlinear spring arrangement with a decreasing spring characteristic curve has the particular advantage that in drive trains for stationary applications, a static torque transmission can be achieved before the operating point is reached.

[0016] Compared to zero-stiffness concepts, which achieve vibration isolation only through almost zero stiffness and therefore do not allow static load transmission, the torsional vibration isolating coupling according to the invention offers the possibility of static torque transmission in the operating point in combination with vibration isolation. This concept utilizes the nonlinearity of the degressive spring characteristic curve of the spring arrangement of the damping unit for this purpose.

[0017] In one embodiment, the at least one nonlinear spring arrangement has at least one spring with a positive spring rate k PSE The spring element and at least one spring element having a negative spring rate k NSE This allows a very simple and compact design.

[0018] A further embodiment provides that a first coupling part as an input side of the coupling is coupled to a second coupling part as an output side of the coupling via a damping unit having the at least one nonlinear spring arrangement.

[0019] Compared to couplings with linear spring characteristics, the torsional vibration isolating coupling of the present invention is able to advantageously transmit static drive torques while enabling broadband vibration isolation during stationary operation of the application. Thus, the benefit of the proposed solution is an improved powertrain dynamics without the need for additional damping components.

[0020] In another embodiment, it is provided that the at least one nonlinear spring arrangement forms a joint in the form of a plate between the at least one spring arrangement for bidirectional force and motion transmission, the spring arrangement cooperating with the plate and the first coupling part of the coupling. This allows a very simple design.

[0021] Another embodiment provides that the plate is coupled to the second coupling part of the coupling via a connecting rod. The connecting rod is of a very simple design.

[0022] A very compact design is achieved if the plate is guided in a receiving chamber of the first coupling part of the coupling so as to be slidable in a translation direction u, wherein the translation direction u extends in a tangential direction of the first coupling part of the coupling.

[0023] If the at least one spring arrangement has a negative spring rate k NSE The at least one spring element advantageously comprises two spring elements arranged in pairs and obliquely to the translation direction u, wherein the first ends of the two spring elements are articulated at a distance from one another on the first coupling part of the coupling, and the other ends of the two spring elements are articulated at a common articulation point on a plate or an intermediate plate cooperating with the plate. In this way, a negative stiffness structure can be realized with simple spring elements.

[0024] Here, it is provided that the distance between the first ends of the spring elements extends in a direction perpendicular to the translation direction u. This has the advantage of a simple structure.

[0025] The torsional vibration isolating coupling can advantageously provide torsional vibration isolation for positive and negative static torques T in this way if the intermediate plate is arranged on the end face of the plate without being connected to the plate.

[0026] It is advantageous for a compact and simple construction if the first coupling part of the coupling and the second coupling part of the coupling are arranged coaxially with respect to one another.

[0027] In one embodiment, the torsional vibration isolating coupling is a coupling of a drive train for stationary applications, in particular a coupling of a drive train of a stationary internal combustion engine. Thus, broadband vibration isolation of the drive train is advantageously achieved.

[0028] The invention proposes a concept with a decreasing spring characteristic curve for a drive train for stationary applications. In contrast to the prior art, the concept meets both the requirements for static torque transmission and the requirements for wide-band vibration isolation without requiring additional functional units. Due to the use of a conventional coupling in combination with a negative stiffness element, a nonlinear spring characteristic curve is obtained. In this case, the spring stiffness of almost zero in the stable operating point of the internal combustion engine / motor makes it possible to achieve almost complete vibration isolation of the connected components.

[0029] Further advantageous developments of the invention can be gathered from the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Some embodiments of the present invention are described below with reference to the accompanying drawings. The present invention is not limited to these embodiments. In particular, the features of the following embodiments can be applied not only in these embodiments, but also in other embodiments. The accompanying drawings show:

[0031] Figures 1 to 2 is a schematic diagram of the first embodiment of the torsional vibration isolation coupling of the present invention in a no-load state;

[0032] Figures 3 to 4 is based on Figures 1 to 2 A schematic diagram of the first embodiment in a loaded state;

[0033] Figures 5 to 6 is a schematic diagram of a second embodiment of the torsional vibration isolation coupling of the present invention in a no-load state;

[0034] Figures 7 to 8 is based on Figures 5 to 6 A schematic diagram of the second embodiment of the present invention in a loaded state;

[0035] Figures 9 to 10 is a symbolic representation of a spring arrangement assembly; and

[0036] Fig.11 is a schematic diagram of the spring characteristic curve of a spring arrangement.

[0037] In the following, the terms “outer side” or “inner side” refer to the respective drawing plane, and “axial side” and “radial side” refer to the rotation axis 1 a of the torsional vibration isolating coupling 1 . DETAILED DESCRIPTION

[0038] Figure 1A schematic radial cross-sectional view of a first embodiment of a torsional vibration isolating coupling 1 according to the present invention is shown. Figure 2 Shows Figure 1 The torsional vibration isolating coupling 1 of the present invention is shown in a schematic transverse cross-sectional view in a no-load state.

[0039] The torsional vibration isolating coupling 1 comprises a first coupling part 2 as an input side in the form of a disk with a central recess 2 a , a second coupling part 3 as an output side in the form of a hub or a cylinder, and a damping unit 4 .

[0040] The first coupling part 2 and the second coupling part 3 are arranged concentrically with the rotation axis 1a of the coupling 1. The second coupling part 3 is arranged in the gap 2a of the first coupling part 2.

[0041] In the annular region 2 b of the first coupling part 2 , a damping unit 4 is arranged in a receiving chamber 5 .

[0042] The receiving chamber 5 is formed in a rectangular parallelepiped shape in the annular region of the first coupling part 2 and has inner side walls 5a and 5b tangentially opposite to each other with respect to the rotation axis 1a. The receiving chamber 5 is delimited in the radial direction with respect to the rotation axis 1a by an inner bottom wall 5c and an inner top wall 5d.

[0043] In this first embodiment, the damping unit 4 comprises a plate 6 and a spring arrangement 10 .

[0044] The plate 6 is guided in the receiving chamber 5 so as to be slidable in a translation direction u via a bottom wall 5 c and a top wall 5 d .

[0045] Between the plate 6 and the inner wall 5 a (here arranged on the left side of the plate 6 ), a spring arrangement 10 connects the plate 6 to the inner wall 5 a of the receiving chamber 5 of the first coupling part 2 .

[0046] The spring arrangement 10 is designed as a nonlinear spring arrangement 10, which comprises a spring having a positive spring rate k PSE The spring element 8 and a spring element having a negative spring rate k NSE The spring element 9 has a positive spring rate k PSE The spring element 8 has a negative spring rate k NSE The spring elements 9 are arranged in parallel with each other.

[0047] With positive spring rate k PSE The spring element 8 is connected in an articulated manner with a first spring end to the inner wall 5 a of the receiving chamber 5 of the first coupling part 2 and is therefore coupled to the first coupling part 2 .

[0048] With positive spring rate k PSEThe other spring end of the spring element 8 is hingedly connected to the plate 6 .

[0049] With negative spring rate k NSE The spring element 9 is composed of two spring elements 9a and 9b arranged in pairs and obliquely to the translation direction u. The first ends of the spring elements 9a and 9b are articulated and connected to the inner wall 5a of the receiving chamber 5 of the first coupling component 2 at a distance from each other. This distance extends in a direction perpendicular to the translation direction u. Here, the two spring elements 9a and 9b are articulated and connected to the plate 6 at a common hinge point with their other spring ends.

[0050] A connecting rod 7 connects the plate 6 to the second coupling part 3. In this way, the first coupling part 2 as the input side of the coupling 1 and the second coupling part 3 as the output side of the coupling 1 are connected here by the connecting rod 7 via the damping unit 4 with the spring fitting 10.

[0051] In this way, the plate 6 forms the joint between the first coupling part 2, the spring arrangement 10 and the second coupling part 3 for bidirectional force transmission, in this case via the connecting rod 7. In addition, the plate 6 forms a motion deflection device for the movement of the connecting rod 7, which transmits the rotational movement of the second coupling part 3 to the plate 6.

[0052] Figure 2 The no-load state of the coupling 1 is shown, in which the value of the torque T is zero and the torsion angle between the first coupling part 2 and the second coupling part 3 about the rotation axis 1a is The value of is also zero. In the unloaded state, all spring elements 8, 9a, 9b of the spring arrangement 10 are completely relaxed. Here, the plate 6 is located in the center of the receiving chamber 5, where it is at the same distance from the two inner side walls 5a, 5b of the receiving chamber 5 in the translation direction u.

[0053] Figure 3 Shown with Figure 1 Schematic radial section through the same coupling 1 . Figure 4 Shows Figure 3 The torsional vibration isolating coupling 1 of the present invention is shown in a schematic transverse cross-sectional view in a loaded state.

[0054] exist Figure 4 In the figure, the coupling 1 is shown by way of example in a working point (WP, see also Fig.11 ). In the example shown, the torque T acts in the counterclockwise direction about the rotation axis 1a. Here, the torsion angle between the first coupling part 2 and the second coupling part 3 is Not equal to 0.

[0055] The plate 6 is moved towards the left inner wall 5 a of the receiving chamber 5 of the first coupling part 2 , wherein the spring elements 8 , 9 a , 9 b of the spring arrangement 10 are compressed.

[0056] The spring arrangement 10 shown enables a static torque T to be transmitted, regardless of the direction of the torque. Torsional vibration isolation by the torsional vibration isolating coupling 1 is achieved here only for static torques T acting in a positive direction, here in the counterclockwise direction about the rotation axis 1a. The term "positive" here means that the torque T causes the plate 6 of the damping unit 4 to move in a positive translation direction u, wherein the plate 6 compresses the spring elements 8, 9a, 9b towards the left inner wall 5a of the receiving chamber 5 of the first coupling part 2.

[0057] Figure 5 and Figure 1 A schematic radial section through the coupling 1 is also shown. Figure 6 2 is a schematic cross-sectional view of a second embodiment of a torsional vibration isolating coupling 1 according to the present invention in a no-load state (T=0).

[0058] According to Figure 2 In contrast to the first exemplary embodiment of the present invention, the damping unit 4 of the coupling 1 has two non-linear spring arrangement components 10 and 10 ′ which are arranged in a mirror-symmetrical manner with respect to an imaginary radial center line of the plate 6 in the receiving chamber 5 of the first coupling part 2 .

[0059] A further difference from the first embodiment is that the spring elements 8, 9a, 9b of the first spring arrangement 10 and the spring elements 8', 9'a, 9'b of the second spring arrangement 10' arranged mirror-symmetrically to the first spring arrangement 10 are respectively connected to an intermediate plate 6c, 6d with their other ends. In this way, the nonlinear damping unit 4 in this case comprises two spring elements 8, 9a, 9b, each having a positive stiffness (k PSE ) of the spring element 8, 8' and a spring element with negative stiffness (k NSE )' is connected in parallel.

[0060] The first intermediate plate 6c is arranged on the first end face 6a of the plate 6, and the second intermediate plate 6d is arranged on the second end face 6b of the plate 6. However, the intermediate plates 6c, 6d are not connected to the plate 6.

[0061] In the loaded state of the second embodiment of the coupling 1 (in Figure 8, a first loaded state in the working point (WP) is shown by way of example when loaded with a positive static torque T, wherein the intermediate plate 6d remains in its unloaded position since it is not connected to the plate 6, wherein the other intermediate plate 6c is pressed by the plate 6 onto the spring configuration assembly 10 and compresses the spring elements 8, 9a, 9b towards the inner wall 5a.

[0062] In this way, the second embodiment of the torsional vibration isolating coupling 1 can achieve torsional vibration isolation of both positive static torque and negative static torque.

[0063] Fig. 9 and 10 A symbolic representation of a spring arrangement 10 , 10 ′ is shown.

[0064] Fig. 9 and 10 Schematically showing a torsional vibration isolation solution of the torsional vibration isolation coupling 1.

[0065] The first spring arrangement 10 comprises a spring having a positive spring rate k PSE The spring element 8 has a negative spring rate k NSE The spring element 9 is composed of spring elements 9a and 9b. The spring arrangement 10 is arranged between the first coupling part 2 and the plate 6 as described above.

[0066] Spring element 8(k PSE ) and 9a, 9b(k NSE ) in parallel to achieve a total spring stiffness k total , whose stiffness is determined by two spring elements 8(k PSE ) and 9(k NSE ) is obtained by adding the spring characteristic curves 11 and 12 of Fig.10 This is shown schematically in the following. Fig.11 Get further explanation.

[0067] The above description also applies to the spring element 8' (k PSE ) and 9'a, 9'b(k NSE ) of the second spring configuration assembly 10'.

[0068] Fig.11 A corresponding spring characteristic curve is shown, which is a schematic representation of a spring characteristic curve of a spring arrangement 10 , 10 ′.

[0069] The torsion angle between the coupling parts 2 and 3 is plotted on the X-axis of the diagram. (Unit: grd / degree). The torque T (unit: Nm) is plotted on the Y axis.

[0070] The schematic diagram shows a positive stiffness k PSE The spring characteristic curve 11 of the spring element 8, 8' has a negative stiffness k NSE The spring characteristic curve 12 of the spring element 9, 9' and the spring characteristic curve 12 with a total stiffness k total The decreasing spring characteristic curve 13 of the spring arrangement 10 , 10 ′.

[0071] The working point of the coupling 1 (at this working point, the torque transmitted is T = 5000Nm and the torsion angle is The static coupling torsion) is marked with reference numeral 14. In this operating point 14, the stiffness of the spring element 8, 8' with positive stiffness kPSE is increased by the stiffness of the spring element 8, 8' with negative stiffness k NSE The spring elements 9 , 9 ′ are compensated so that the resulting decreasing spring characteristic curve 13 of the coupling 1 has a very low overall stiffness in this operating point 14 (horizontal extension of the spring characteristic curve 13 ).

[0072] Outside this operating point 14, the decreasing spring characteristic curve 13 of the coupling 1 has a characteristic curve which increases with the deflection, ie with the torsion angle This nonlinearity of the decreasing spring characteristic curve 13 of the coupling 1 allows, on the one hand, the transmission of statically acting coupling torques T and, on the other hand, decoupling / isolating the drive train from fluctuations in torque T occurring in the stable operating point 14 .

[0073] Reference numerals list

[0074] Coupling 1

[0075] Rotation axis 1a

[0076] First coupling part 2

[0077] Gap 2a

[0078] Ring area 2b

[0079] Second coupling component 3

[0080] Damping unit 4

[0081] Accommodation room 5

[0082] Side walls 5a, 5b

[0083] Bottom wall 5c

[0084] Top wall 5d

[0085] Plate 6

[0086] End faces 6a, 6b

[0087] Intermediate plates 6c, 6d

[0088] Connecting rod 7

[0089] Spring elements 8, 8'

[0090] Spring elements 9, 9a, 9b; 9', 9'a, 9'b Spring arrangement assembly 10, 10'

[0091] Spring characteristic curves 11, 12, 13

[0092] Working point 14

[0093] Spring stiffness k

[0094] Translation direction u

[0095] Torque T

[0096] Torsion Angle

Claims

1. A torsional vibration isolating coupling (1) having a rotation axis (1a), the coupling comprising a first coupling component (2) as an input side of the coupling (1), a second coupling component (3) as an output side of the coupling (1) and a damping unit (4), characterized in that: The damping unit (4) has at least one spring arrangement (10, 10') which is designed as a nonlinear spring arrangement (10, 10') with a decreasing spring characteristic curve (13).

2. The torsional vibration isolation coupling (1) according to claim 1, characterized in that: The at least one nonlinear spring arrangement (10, 10') has at least one spring with a positive spring rate k PSE The spring element (8, 8') and at least one spring element having a negative spring rate k NSE Spring element (9, 9').

3. The torsional vibration isolation coupling (1) according to claim 2, characterized in that: A first coupling part (2) as an input side of the coupling (1) is connected to a second coupling part (3) as an output side of the coupling (1) via a damping unit (4) having at least one nonlinear spring arrangement component (10, 10').

4. The torsional vibration isolation coupling (1) according to claim 3, characterized in that: The at least one nonlinear spring arrangement (10, 10') forms a joint in the form of a plate (6) between the at least one spring arrangement (10, 10') for bidirectional force and motion transmission, the spring arrangement cooperating with the plate (6) and a first coupling part (2) of the coupling (1).

5. The torsional vibration isolation coupling (1) according to claim 4, characterized in that: The plate (6) is connected to the second coupling part (3) of the coupling (1) via a connecting rod (7).

6. The torsional vibration isolating coupling (1) according to claim 4 or 5, characterized in that: The plate (6) is slidably guided in a receiving chamber (5) of a first coupling part (2) of the coupling (1) in a translation direction u, wherein the translation direction u extends in a tangential direction of the first coupling part (2) of the coupling (1).

7. The torsional vibration isolation coupling (1) according to claim 6, characterized in that: The at least one spring arrangement (10, 10') has a negative spring rate k NSE The spring element (9, 9') has two spring elements (9a, 9b) arranged in pairs and inclined to the translation direction u, wherein the first ends of the two spring elements (9a, 9b) are hingedly connected to the first coupling part (2) of the coupling (1) at a distance from each other, and the other ends of the two spring elements (9a, 9b) are hingedly connected to the plate (6) or to an intermediate plate (6c, 6d) cooperating with the plate (6) at a common hinge point.

8. The torsional vibration isolation coupling (1) according to claim 7, characterized in that: The distance between the first ends of the spring elements (9a, 9b) extends in a direction perpendicular to the translation direction u.

9. The torsional vibration isolating coupling (1) according to any one of claims 7 or 8, characterized in that: The intermediate plates (6c, 6d) are arranged on the end faces (6a, 6b) of the plate (6) without being connected to the plate (6).

10. The torsional vibration isolating coupling (1) according to any one of the preceding claims, characterized in that The first coupling component (2) of the coupling (1) and the second coupling component (3) of the coupling (1) are arranged coaxially with each other.

11. The torsional vibration isolating coupling (1) according to any one of the preceding claims, characterized in that The coupling (1) is a coupling (1) for a drive train of a stationary application, in particular a coupling for a drive train of a stationary internal combustion engine.

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