Spring and system

Abstract

A spring (60) comprising at least one spring section (62) which, when projected onto a cross-sectional area (64) perpendicular to a force direction (66) of the spring (60) in an unloaded state, extends over an arc of at least 90°, wherein the spring section (62) has an elliptical shape when projected, and wherein the spring comprises an additional section (76) which, when projected onto an additional cross-sectional area (78) perpendicular to the force direction (66) of the spring (60) in the unloaded state, has a circular shape, characterized in that a first semi-axis (80) of the elliptical shape corresponds to a radius (72) of the circular shape of the additional section (76).

Description

[0001] Embodiments relate to a spring and a system with at least one spring, which may be, for example, a torsional vibration damper.

[0002] In many areas of technology, springs are used to absorb forces. For example, springs are used to make systems capable of oscillation by mechanically coupling two components using at least one spring. Several options exist for mechanical coupling to enable force transmission between these components and the at least one spring. For example, DE 10 2010 002 120 A1 refers to a compression spring made of spring wire wound around a spring axis. Such a system can be, for example, a torsional vibration damper, which can also be integrated into a larger system or another assembly.

[0003] Spring plates are used to control the spring ends of at least one spring. However, this can entail additional costs. Furthermore, some spring ends may not be controlled accurately by certain components, which could cause the spring to shift from its intended position and potentially cause increased wear or even complete failure of the system. The control of the springs can therefore have a direct impact on the operational reliability and maintenance requirements of such a system. At the same time, the control of at least one spring should, if possible, be implemented by the relevant components using simple and therefore cost-effective means.

[0004] Comparable embodiments are known from the documents DE 199 09 044 A1, SU 886817 A2, JP 2001- 263 236 A, US 3 157 455 A, EP 1 125 806 A1 and DE 10 2009 015 577 A1.

[0005] There is therefore a need to improve the compromise between the manufacture of springs, their integration into a system, operational reliability, and the maintenance requirements of such a system. A spring according to claim 1 and a system according to claim 10 address this need.

[0006] A spring according to one embodiment comprises at least one spring section which, when projected onto a cross-sectional area perpendicular to a force direction of the spring in an unloaded state, extends over an arc of at least 90°. The spring section has an elliptical profile when projected, wherein the spring comprises an additional section which, when projected onto an additional cross-sectional area perpendicular to the force direction of the spring in the unloaded state, has a circular profile, wherein a first semi-axis of the elliptical profile corresponds to a radius of the circular profile of the additional section. Such a spring can be designed, for example, as a torsion spring or helical spring. This type of spring can, for example, be made from a spring wire wound around a spring axis.The spring wire, for example, can be made of a metallic material. Such a metallic material can comprise, for example, a metal, a metallic alloy, such as brass, or a metal or metallic alloy with non-metallic components, such as steel. Likewise, the metallic material can also comprise other metallic and / or non-metallic components, such as carbon fibers or glass fibers.

[0007] The direction of force can coincide with the spring axis. A spring according to one embodiment can, for example, be designed or used as a compression or tension spring. This means that it can, for example, counteract forces that can compress or stretch the spring. Thus, the spring can also be subjected to compression or tension when integrated into such a system.

[0008] A spring according to one embodiment can thus at least partially have a coil wound around the spring axis with a coil radius perpendicular to the axis. Such a spring can have a constant coil radius and / or a varying coil radius. Thus, such a spring can be configured, at least in sections, as a helical spring or as a barrel or coil spring.

[0009] The at least one spring section can, for example, be arranged at one end of the spring, but can also be arranged at a different location on the spring. An elliptical shape is understood to mean any type of elliptical configuration or ellipse that has two semi-axes of different sizes. The special case of a circle, in which both semi-axes are the same size, does not constitute an ellipse. In other words, the eccentricity of the ellipse is not equal to zero. The eccentricity can be defined as the square root of the difference between the square of the major semi-axis and the square of the minor semi-axis. This eccentricity is also referred to as linear eccentricity. A projection can be understood to mean, in particular, the so-called orthogonal projection. In other words, it can be a projection of a mathematical set of points perpendicular to a plane.In particular, the point set can also be an extended body such as a spring or a spring segment.

[0010] The elliptical shape of the spring section makes it possible to control the spring very precisely, even without using, for example, a specially designed spring plate. In other words, the elliptical shape of the spring section can simplify the control of the spring and thus the design of the component used to control the spring. This makes it possible to achieve a compromise between easier control of the spring, integration of the spring into a corresponding system, and improved manufacturing effort. This can potentially reduce manufacturing costs, while at the same time preventing malfunctions or at least reducing their occurrence. Such a malfunction can, for example, include tilting of the spring.

[0011] Optionally, in such an embodiment, the spring can comprise an additional section which, when projected onto an additional cross-sectional area perpendicular to the direction of force of the spring in the unloaded state, has a circular shape. "Circular" can be understood here as "following a circular arc." A circle is understood here to be the case in which the eccentricity is zero, i.e. both semi-axes are of equal size. It is therefore not an ellipse in the sense defined above. The circular shape can extend over any desired angle, i.e. not just over one or more full circles in the sense of integer multiples of 360°, but also values ​​in between. A circular cross-section of the additional section of the spring can potentially make more effective use of available installation space.

[0012] In such an embodiment, a first semi-axis of the elliptical profile can optionally correspond to a radius of the circular profile of the additional section. In other words, with such a spring, only one of the two semi-axes of the elliptical profile can differ from the radius of the circular profile. This simplifies manufacturing. Additionally or alternatively, it may also be possible to enable more efficient use of the installation space.

[0013] Optionally, in such an embodiment, a second semi-axis of the elliptical curve can be smaller by a predefined value than the first semi-axis. In such a case, the first and second semi-axis of the elliptical curve can each be referred to as their major and minor semi-axes. The terms "large" and "small" indicate that the special case of a circle is excluded from this. A system in which a component controls the spring can therefore be manufactured more easily, since, for example, a spring plate specifically designed for control or a corresponding control component can be omitted. The special sizes of the semi-axes described above can also, in addition or alternatively, achieve greater stability, since slipping or tilting of the spring becomes less likely.

[0014] Additionally or alternatively, the spring can have coils wound from a spring wire, in which the spring section comprises at least one coil, and in which a pitch of the at least one coil in the spring section is smaller than a pitch of a coil outside the spring section. As already mentioned at the beginning, the spring wire can be made of different materials. A coil can represent a course of the spring wire that can extend over any desired angle. In addition to integer multiples of 360°, this can also be any other angle. A region of smaller pitch can, if necessary, be accompanied by a changed spring constant.Irrespective of this, an implementation of the smaller pitch of the spring section may have a positive effect on the stability of the spring section, since the risk of mechanical deformations under a basic load of the spring may be reduced.

[0015] Optionally, in exemplary embodiments, the at least one turn in the spring section can at least partially comprise a dead turn. A dead turn can represent a turn whose adjacent turns at least partially touch each other. "At least partially" means that the contact surface can also extend over an arc width of less than 360°. Furthermore, all of these turns can have an elliptical shape. Optionally, for example, all or some of the turns of the spring section with the elliptical shape can also be designed as dead turns. This may possibly make it possible to further mechanically stabilize the spring or its spring section.

[0016] Additionally or alternatively, the spring section can be arranged at one end of the spring. This can facilitate easier integration of the spring into a system, as the spring can be more easily controlled at such an end.

[0017] In exemplary embodiments, the force direction can additionally or alternatively follow the course of a circular arc segment. In other words, the spring used can also be designed as an arc spring. However, implementation options may also exist for springs whose force direction follows a straight line. By implementing an arc spring, it may be possible to control the spring using forces that are at an angle other than 0° to each other, i.e., forces that do not act collinearly or parallel.

[0018] Embodiments can additionally or alternatively relate to a spring that comprises a further spring section. In this case, the further spring section can extend, in a further projection onto a further cross-sectional area perpendicular to the direction of force of the spring in the unloaded state thereof, over an arc of at least 90°, which has an elliptical shape in the further projection. The spring section and the further spring section can be designed similarly or identically with regard to a single feature, several features, or all features. Structural embodiments, as described above and also described below, can relate independently of one another, for example, to the spring section and the further spring section. For example, the dimensions of the latter can be selected accordingly, to name just one example.The structural configurations can also relate to individual properties of the spring wire or spring, for example. These can include pitch, material, load capacity, thickness, or geometric properties such as the cross-section. The presence of an additional spring section can simplify the control of the spring from another direction.

[0019] Optionally, in such an embodiment, the spring section can be arranged at one end of the spring, and the further spring section can be arranged at an end of the spring facing away from the spring section. This arrangement can potentially allow for particularly easy production of the spring. Additionally or alternatively, this can potentially enable easier and possibly more stable control of both ends of the spring simultaneously.

[0020] Additionally or alternatively, according to one embodiment, the spring can have an intermediate section which, in a supplementary projection onto a supplementary cross-sectional area perpendicular to the direction of force of the spring in the unloaded state thereof, extends over an arc of at least 90°, and in the supplementary projection has a supplementary elliptical shape. A minor semi-axis of the supplementary elliptical shape of the intermediate section can deviate from the minor semi-axis of the elliptical shape of the spring section. The intermediate section and the spring section can optionally be arranged adjacent to one another. This can make it possible, for example, for two adjacent or adjacent sections of the spring, namely the spring section and the intermediate section, both to have an elliptical shape but with different eccentricities. For example,It may be useful to arrange a less strongly retracted intermediate section next to a strongly retracted spring section to increase the spring's stability under load. Two objects are adjacent if there is no other object of the same type between them. Objects are immediately adjacent if they are adjacent to one another, for example, if they are in contact with each other.

[0021] In exemplary embodiments, the spring can additionally or alternatively be ground at at least one end such that a ground surface is aligned substantially perpendicular to the direction of force of the spring. "Substantially perpendicular to the direction of force of the spring" can mean that the angle between the direction of force and the ground surface can deviate from a right angle (90°), for example, due to manufacturing accuracy or tolerances. This can further facilitate control and thus ensure greater operational reliability.

[0022] A system according to one embodiment comprises a first component, a second component, and at least one spring according to one embodiment, as previously described. The spring portion of the at least one spring bears against the first component. It is further mechanically coupled to the second component. The at least one spring thus has at least partially a positive connection with the first component, which, however, can be supplemented by non-positive and / or material-locking connection portions or connection components. A mechanical coupling of two components comprises both a direct and an indirect coupling. A non-positive or frictional connection is created by static friction, a material-locking connection by molecular or atomic interactions and forces, and a positive connection by a geometric connection of the respective connection partners.Static friction therefore generally requires a normal force component between the two connecting partners.

[0023] Both the first and the second component can be designed as a single piece or as a multi-piece component, for example in the form of several cover plates, which can optionally be connected to one another using spacer rivets or other components. The case of a multi-piece implementation thus also includes a multi-component design of the component in question. A single-piece component is understood to be one that is made exactly from a single, continuous piece of material. A single-piece component or structure, provided or manufactured, or a component or structure manufactured, provided or manufactured integrally with at least one other component or structure is understood to be one that cannot be separated from the at least one other component without destroying or damaging one of the at least two components involved.A one-piece component thus also represents at least one component that is manufactured integrally with another structure of the component in question or that is a one-piece component.

[0024] In other words, the system can be a vibration-capable system. The spring can, for example, serve to compensate for vibrations occurring between the first and second components, or for shocks or impact loads. Possible applications for such systems can exist in the field of mechanical engineering, e.g., automotive engineering, but are by no means limited to these. This can make it possible to simplify the control of the spring via its spring section if necessary. For example, the elliptical shape of the spring section can make the control of the spring by the first component structurally simpler.

[0025] In such an embodiment, the first component can optionally be made at least partially or entirely from a sheet-like material. In this case, the first component can rest with an edge against the spring section. A sheet-like material can, for example, comprise or consist of a metallic material. Metallic materials also include, as already explained, alloys of metals with non-metals. Sheets can, for example, be produced by rolling metallic materials. However, other manufacturing options may also exist. A sheet-like material can be one in which one of its three dimensions along its three linearly independent extension directions - height, length, and width - is smaller than the other two by at least a predetermined factor, for example by at least one order of magnitude (at least a factor of 10).The smallest dimension can also be referred to as "thickness," whereby the edge of the component made from the sheet-like material refers to the direction of extension of the component in which the component has the smallest dimension. In other words, the thickness of the component represents the dimension of the component along the edge. Sheets can often have a thickness of only a few 10 µm, several 100 µm, a few millimeters, or even a few centimeters. Apart from that, however, there can also be heavy plates in a higher thickness range. By using at least one spring according to one embodiment, production of the first component and thus the integration of the at least one spring can be simplified if necessary.

[0026] Additionally or alternatively, in a system according to one embodiment, the at least one spring can have a further spring section. The further spring section can, in a further projection onto a further cross-sectional area perpendicular to the direction of force of the spring in the unloaded state of the spring, extend over an arc of at least 90°, which has an elliptical shape in the further projection. The second component can rest with an edge on the further spring section. This can make it possible to simplify control of the spring not only by the first component, but also by the second component. This can possibly make it possible to simplify integration of the spring into the system.

[0027] Optionally, in such a system according to one embodiment, in which the at least one spring also bears against the second component, the second component can also be made at least partially or entirely from a sheet-like material. The second component can bear against the further spring section with one edge. By using at least one spring configured in this way according to one embodiment, the manufacture of the second component and thus the integration of the at least one spring can be simplified.

[0028] The system can therefore, for example, comprise two components made of a sheet-like material, which can also be referred to as sheets, each of which rests with its edge on one end of the spring.

[0029] Additionally or alternatively, a system according to one embodiment may be a torsional vibration damper. Such a torsional vibration damper, also referred to as a vibration damper, can be used, for example, in the field of vehicle construction, for example, in the drive train of a motor vehicle. In this case, the first and / or second component can be a guide plate, a control plate, a hub disc, or a central disc. However, a spring according to one embodiment can also be used in other areas.

[0030] In the following, embodiments and also conventional implementations are described and explained in more detail with reference to the attached figures. Fig. 1 shows a comparative example of a torsion spring in a top view; Fig. Figure 2a shows a cross-sectional view of a conventional torsion spring; Fig. 2b shows a perspective view of a comparative example of a torsion spring; Fig. 3 shows a perspective cross-sectional view through a torsion damper with a conventional spring; Fig. 4 shows a perspective cross-sectional view through another conventional torsion damper; Fig. 5 shows a perspective cross-sectional view through a conventional torsional vibration damper; Fig. 6a shows a side view of a spring according to an embodiment in the form of a bow spring; Fig. 6b shows another side view of the 90° angled view of the Fig. 6a twisted spring according to an embodiment of Fig. 6a; Fig. Figure 6c shows a top view of the Fig. 6a and Fig. 6b shows a spring according to an embodiment; Fig. 7a shows a perspective partial cross-sectional view through a system according to an embodiment in the form of a torsional vibration damper; Fig. 7b shows an enlarged partial view of Fig. 7a; Fig. 8 shows a perspective cross-sectional view through an embodiment of a system according to an embodiment in the form of a torsional vibration damper; Fig. 9 shows a cross-sectional view through a system according to an embodiment in the form of a torsional vibration damper; Fig. 10a shows a side view of a spring according to an embodiment in the form of a bow spring; Fig. 10b shows another side view of the 90° angled view of the Fig. 10a twisted spring according to an embodiment of Fig. 10a; Fig. 10c shows a top view of the Fig. 10a and Fig. 10b shows a spring according to an embodiment; Fig. 11a shows a side view of a spring according to an embodiment in the form of a bow spring; Fig. 11b shows another side view of the 90° angled view of the Fig. 11a twisted spring according to an embodiment of Fig. 11a; and Fig. 11c shows a top view of the Fig. 11a and Fig. 11b shown spring according to an embodiment.

[0031] In the following description of the accompanying illustrations, identical reference numerals designate identical or comparable components. Furthermore, collective reference numerals are used for components and objects that appear multiple times in an embodiment or illustration, but are described together with respect to one or more features. Components or objects described with identical or collective reference numerals may be identical with respect to individual, several, or all features, such as their dimensions, but may also be different, unless the description explicitly or implicitly indicates otherwise.

[0032] Fig. 1 shows a plan view of a conventional compression spring 10 with a spring end 12. Fig. 1 shows the compression spring 10 viewed along a force direction 13 parallel to a spring axis 16. The spring end 12 has an end coil 20 whose outer diameter 21 is smaller than the outer diameter 14 of an adjacent coil 22. More precisely, the end coil 20 is spirally drawn in compared to the adjacent coil 22, so that its outer diameter, up to a free end 24 of the spring end 12 of the compression spring 10, lies entirely within the outer diameter 14 of the adjacent coil 22.

[0033] Fig. Figure 2a shows a cross-sectional view through another conventional compression spring 10, in which the spring axis 16 has a curved profile. Furthermore, a pitch 32 of the end coil 20 is reduced to such an extent compared to a pitch 30 of the adjacent coil 22 that the end coil 20 represents a dead coil. Thus, the end coil 20 touches the neighboring or adjacent coil 22, so that the position of the end coil 20 is fixed relative to the coil 22. A change in the position of the end coil 20 relative to the adjacent coil 22 is not possible, or not significantly possible, so that no or no significant spring effect can be achieved by the end coil 20. For this reason, the end coil 20 is also referred to as a dead coil.

[0034] Fig. 2a shows a cross section through a plane that includes the spring axis 16. The compression spring 10 can, for example, be arranged in a spring channel 28. The spring channel 28 thus defines an available installation space 29, which in Fig. 2a by dotted-dashed lines. This cross-section also shows that the end coil 20 has a ground surface 34 that is substantially perpendicular to the spring axis 16. The ground surface 34 can be produced by grinding the spring end 20. In this case, Fig. In the compression spring 10 shown in Figure 2a, the ground surface 34 is arranged in such a way that it removes a portion of the end coil 20. In other words, the compression spring 10 is ground in such a way that the aforementioned portion of the end coil 20 has been removed.

[0035] Fig. Figure 2b shows a perspective view of the conventional compression spring 10, with the viewing direction parallel to the plane of the ground surface 34. The arrows 36 mark the course of the cross-sectional area of ​​the Fig. 2a shown view. How Fig. 2a shows, the end coil 20 is also continuously retracted in this conventional compression spring 10. An arrow 38 indicates the beginning of a region of the free end 24 from which the end coil 20 is retracted. Fig. 1, Fig. 2a and Fig. 2b show springs bent in this way with continuously retracted spring ends or springs whose end turn 20 has a smaller winding radius than that of other turns, for example the adjacent turn 22. However, with these approaches, controlling such a compression spring 10 can be comparatively difficult.

[0036] As already explained at the beginning, there is a need to enable easier control of a spring using a corresponding component within a larger system. Thus, according to one exemplary embodiment, a spring described in more detail below can make it possible to control such a spring even without the use of an additional control element, such as a spring plate. This can make it possible to reduce manufacturing effort and potentially associated costs.

[0037] The omission of a spring plate, for example in a torsional vibration damper, can result in the ground spring end 12 not being able to be correctly controlled by a corresponding component under all operating conditions. To illustrate this in more detail, Fig. 3 a perspective cross-sectional view through a conventional torsional vibration damper 40 having a hub disc 41.

[0038] This shows Fig. 3 shows a cross section through the torsional damper 40, in which a conventional compression spring 10 is arranged in a spring channel 44 of a first cover plate 46. In the torsional vibration damper 40, as shown in Fig. 3, it is one that can be used in a starting element of a drive train of a motor vehicle, for example a passenger car, a truck or another commercial vehicle. In this case, a torque flow occurs via the torsional vibration damper from an input side, which can be coupled to the first cover plate or coincide with it, for example, to an output side, which can be mechanically coupled to the hub disc 41 or coincide with it. When the torsional vibration damper 40 is shown according to the torque flow from left to right, the first cover plate 46 is arranged to the right of the hub disc 41, which is why it is also referred to as the right cover plate.

[0039] A spring end 12 of the conventional compression spring 10 is designed here as a ground spring end 12. However, the compression spring 10 has - in contrast to the Fig. 1, Fig. 2a and Fig. 2b shown compression spring 10 - no retracted end. As Fig. 3 shows, the spring does not fully rest on a tab 48 of the hub disc 41. This unfavorable support can result in increased torsional stress on the spring 10. In the worst case, the ground spring end 12 can get caught between the spring channel 44, at least partially formed by the first cover plate 46, and the hub disc 41 and possibly become wedged there. This can, for example, cause increased wear and damage to the torsional vibration damper 40. It can also lead to an unfavorable tolerance position. Wear, damage, an unfavorable tolerance position, and increased torsional stress are examples of conditions that can lead to a failure of the torsional damper 40.

[0040] A conventional solution is to retract the ground spring end 12 radially inwards, as previously described in connection with the Fig. 1, Fig. 2a and Fig. 2b has already been explained. This is in Fig. 4 shown.

[0041] Fig. 4 shows a perspective cross-sectional view through a torsional vibration damper 40, which has a reduced radius 50 of the end coil 20 at the ground spring end 12 compared to a radius 52 of an adjacent coil 22. As already mentioned in connection with the Fig. 1, Fig. 2a and Fig. 2b, the spring end 12 is completely retracted. The spring axis 16 is shown as a dashed line. In the view in Fig. 4 is a representation of a cross-section through a plane that includes the spring axis 16.

[0042] Fig. 5 shows a perspective cross-sectional view of a further cross-section perpendicular to the cross-sectional plane of Fig. 4. Fig. 5 again shows the spring 10, which is arranged in the spring channel 44. Although the hub disc 41 is now better protected by the ground spring end 12 than in the Fig. 3, problems can still arise when controlling the first cover plate 46 and a second cover plate 54, which is arranged on a side of the hub disc 41 facing away from the first cover plate 46. This can happen because the ground spring end 12 does not necessarily rest completely on a control surface 56-1 of the first cover plate 46 and a control surface 56-2 of the second cover plate 54. Thus, if the end coil 20 is completely retracted or the spring end 12 is continuously retracted, the compression spring 10 may no longer be able to be controlled to the intended extent by the second cover plate 54.Additionally or alternatively, the spring end 12 can slip off a control surface 56 of the first cover plate 46 or the second cover plate 54, which in the worst case can lead to a lateral exit of the spring 10 from the spring channel 44 and thus to a failure of the torsional vibration damper 40, which is also referred to as damper failure.

[0043] In the above-described illustration of the torsional vibration damper 40, in which the torque or rotational movement is transmitted from left to right, the second cover plate 54 is arranged to the left of the hub disc 41. For this reason, the second cover plate 54 is also referred to as the left cover plate. In the torsional vibration damper 40 shown here, both cover plates 46, 54 together form the spring channel 44, which has a circular cross-section. The hub disc 41 is arranged between the two cover plates 46, 54, which is why it is also referred to as the central disc.

[0044] In order to enable a better and possibly more reliable control of a spring through the hub disc 41 and through the cover plates 46, 54, a spring according to an embodiment can now be used. Such a spring is, for example, in the Fig. 6a to 6c. In these, one end 68 of the spring 60 is elliptically retracted.

[0045] Fig. Figure 6a shows a side view of a spring 60 according to one embodiment, which is configured here as a compression spring. Of course, other embodiments of a spring 60 can also be configured as a tension spring. Fig. 6b also shows another side view of the opposite Fig. 6a spring 60 rotated by 90° and Fig. 6c supervision of the Fig. Spring 60 shown in 6a.

[0046] The spring 60 has a spring section 62 which, when projected onto a Fig. 6c, which extends perpendicularly to the force direction 66 coinciding with the spring axis 16 over an arc of at least 90° in an unloaded state of the spring 60. The spring section 62 has an elliptical profile in the described projection onto the cross-sectional area 64. In other words, the spring 60 in the spring section 62 has a profile of an ellipse, an ellipse segment, or an ellipse section that extends over at least 90°, but can also extend over a larger angular range, for example, over at least 180°, at least 270°, at least 360°, or over at least 540°. Therefore, for the sake of simplicity, this elliptical profile is also referred to simply as an "ellipse."In the spring 60 shown here, the spring section 62 is arranged at one end 68 of the spring 60 (spring end), but in other embodiments, it may also be arranged at a different location on the spring 60. Due to the elliptical shape in the region of the spring section 62 and its arrangement at the end 68 of the spring 60, this is a spring 60 with an elliptically tapered end 68.

[0047] The direction of view in Fig. 6a is perpendicular to a plane encompassing the spring axis 16. A large arrow 70 indicates the direction of force 66 occurring during the compressive load. The direction of force 66 and the spring axis 16 follow an arc or arc segment-shaped course, i.e. a course of a circular arc segment, so that the Fig. 6a to 6c, the spring 60 shown is implemented as a bow spring.

[0048] Fig. 6a further shows two smaller arrows indicating a difference between a radius 72 and a second semi-axis 74 of the elliptical profile in the spring section 62. The radius 72 refers to an additional section 76, which, when projected onto an additional cross-sectional area 78 perpendicular to the force direction 66 of the spring 60 in its unloaded state, has a circular profile. Due to the described arcuate profile of the force direction 66, the cross-sectional areas 64, 78 are not parallel, although this may, of course, be the case in other embodiments.

[0049] The second semi-axis 74 also lies in the representation plane. Fig. 6b shows a representation in a plane which is rotated by 90° compared to the representation of the Fig. 6a and thus includes a first semi-axis 80. It can be seen that the first semi-axis 80 corresponds to the radius 72, while the second semi-axis 74 deviates from the first semi-axis by a predetermined value. Thus, the elliptical shape is not a circular or circular arc, in which the two semi-axes of the "ellipse" would coincide. More precisely, the second semi-axis 74 is smaller than the first semi-axis 80 by a predetermined value. Fig. As Figure 6c also shows, in which the elliptical course is parallel to the representation plane due to the projection onto the cross-sectional plane 64, the elliptical course extends over at least 180° or at least half a turn.

[0050] Furthermore, the end 68 of the spring 60 is ground to facilitate better contact of the spring with a component used to control it. The spring thus has a ground surface 34 at its end 68, which is aligned and arranged essentially perpendicular to the direction of force 66 of the spring. The ground surface 34 is indicated as an outline.

[0051] The spring section 62 is arranged here at the end 68 of the spring. As a result, when actuated by a component of a system, for example a torsional vibration damper, it can be retracted elliptically inward only in the section that is radially outer from the perspective of the torsional vibration damper. In such a case, the spring section 62 can extend by less than 360° around the spring axis 16. This can already achieve a reduction in friction in the spring channel 44. The end 68 of the spring 60 can be Fig. 6c can be located in both the right and left halves. The exact position of the end 60 of the spring can be adjusted to suit the respective situation, e.g., the control option via cover plates or other components.

[0052] A spring 60 according to an embodiment may, in addition to the spring portion 62 and the optional additional portion 76, also comprise one or more further spring portions 62' (not shown in Fig. 6a to 6c), which in terms of their design are similar to the spring section 62, can be identically designed, or can also be completely different. For example, the further spring section 62' can also have an elliptical shape when projected onto a further cross-sectional area in an unloaded state of the spring 60, wherein the shape can extend over at least 90°. The further spring section 62' can thus be arranged, for example, at a further end 68' of the spring 60, which is opposite the end 68 of the spring 60. The spring section 62, the optional additional section 76 as well as the optional further spring section 62' can, for example, comprise at least part of a turn of a spring wire if the spring 60 is to be at least partially constructed from a spring wire wound around a spring axis 16.

[0053] In order to improve the compromise already mentioned above between the production of the spring, its integration, and its control by the system, a spring 60 has at least one spring section 62 which, when projected onto the cross-sectional area 64 perpendicular to the force direction 66 of the spring 60 in an unloaded state, extends over an arc of at least 90°. The spring section 62 has the previously explained elliptical shape when projected.

[0054] Fig. Figure 7a shows a perspective cross-sectional view of a system 90 according to one embodiment. System 90 is a torsional vibration damper 92. More specifically, a section through the system is shown parallel to its central axis. The view is taken at an angle to the resulting cross-sectional plane.

[0055] The torsional vibration damper has a plurality of springs 60 according to one exemplary embodiment. The springs 60 each extend over a circular segment, but are partially arranged at different radii from the central axis. The radially outer springs 60 form a first stage of the torsional vibration damper 92, while the radially inner springs 60 form a second stage of the torsional vibration damper 92. The two stages of the torsional vibration damper 92 are arranged one behind the other in a torque flow, i.e., they are connected in series. The total number of springs 60 can, however, fundamentally vary in a torsional vibration damper 92, just as in another system 90, with the spring designated by reference numeral 60' being described in more detail below.

[0056] It should also be mentioned again that the exemplary embodiments by no means relate only to torsional vibration dampers 92, but the areas of application of the springs 60 presented here are merely exemplary. With regard to the construction of the torsional vibration damper 92, it differs only slightly from the previously described variants. Here, too, the torsional vibration damper has two cover plates 46, 54 and a hub disk 41, to which, for example, the spring 60' is mechanically coupled. At least one of the two cover plates 46, 54, which in other torsional vibration dampers 92 can also be designed differently according to an exemplary embodiment, thus represents a first component 94 and the hub disk 41 a second component 96, both of which are mechanically coupled to the spring 60' in order to be able to vibrate against each other. As will be explained below Fig. 7b, the first component 94 and the second component 96 are both in contact with the spring 60'. The spring 60' thus has, in addition to the spring section 62, a further spring section 62', which can be configured essentially identically to the spring section 62. In Fig. 7a, the first component 94 is designed in several parts and comprises the two cover plates 46 and 54.

[0057] A picture section 98 from Fig. 7a is so in Fig. 7b is shown enlarged. The torsional vibration damper 92 again has the two cover plates 46 and 54, as well as the hub disc 41. The spring 60' is arranged in a spring channel 44 and almost completely fills it with regard to its inner diameter and an outer diameter of the spring 60'. The spring channel 44 has a substantially circular cross-sectional area. The spring 60' again has an end 68, which here, however, is elliptically drawn in. The end 68 of the spring 60' thus represents the spring section 62 arranged at its end.

[0058] In Fig. 7b, the elliptical shape of the spring section 62, i.e., the last coil, extends over approximately 180°, although larger or smaller angular sections may also be considered. The spring 60' also has a ground surface 34 at this end 68. The ground surface 34 largely coincides with Fig. 7b, as previously described. These are the control surfaces 56 of the first cover plate 46, the second cover plate 54, and the hub disc 41. Due to the overlap of the ground surface 34 with the control surfaces 56, it may be possible to enable effective control of the spring 60' by the cover plates 46 and 54 and also by the hub disc 41.

[0059] Even though only spring 60' was considered in the preceding description, this can of course also apply to the other springs 60 according to an exemplary embodiment. Likewise, in exemplary embodiments, conventional springs can also be used in addition to one or more springs 60 according to an exemplary embodiment. Depending on the specific design, this can be possible, for example, in a multi-stage torsional vibration damper 92 for the different stages thereof. The same naturally also applies to other systems 90 according to exemplary embodiments.

[0060] Fig. 8 shows a more detailed cross-sectional view of the spring channel 44 with the spring 60'. The sectional plane here encompasses the first semi-axis 80 of the elliptical profile of the spring section 62. The first semi-axis 80 has the same length as a radius 72 of the circular profile in the additional projection of the additional section 76. The additional section 76 can optionally be included in exemplary embodiments and, in the additional projection onto an additional cross-sectional area perpendicular to the force direction 66 of the spring 60' in its unloaded state, can have the aforementioned circular profile. Fig. Figure 8 clearly shows that the ground surface 34 is in close contact with the control surfaces 56 and has a large overlap with them. Furthermore, as in the embodiment shown here, the spring 60' can have an end turn 77 whose pitch 32 is reduced compared to a pitch 30 of an adjacent turn 79. The turn 79 can, for example, belong entirely or at least partially to the additional spring section 76.

[0061] Fig. 9 shows a further cross section through a cutting plane encompassing the spring axis 16 through the spring 60'. Furthermore, the cutting plane of Fig. 9 a second semi-axis 74 of the elliptical course of the projection of the spring section. Fig. 9 shows that the second semi-axis 74 is smaller than the radius 72.

[0062] How Fig. As already shown in Figure 8, in the spring 60', the first semi-axis 80 of the elliptical profile corresponds to the radius 72 of the circular profile of the additional section 76. The second semi-axis 74 of the elliptical profile is thus smaller than the first semi-axis 80 by a predefined value. A ratio of the smaller second semi-axis 74 to the larger semi-axis 80 can, for example, be approximately between 80 and 98%, taking manufacturing accuracies and tolerances into account, but can also assume other values ​​in other embodiments.

[0063] For example, a spring 60 with a cross-sectional radius of 22 mm can have a spring section 62 with a minor semi-axis of the elliptical shape, which is 0.5 mm to 4 mm smaller than the major semi-axis. Additionally or alternatively, a spring 60 can have coils wound from a spring wire 18. In this case, the spring section 62 can comprise at least one coil, and a pitch 32 of the at least one coil in the spring section 62 can be smaller than a pitch 30 of a coil outside the spring section 62. Optionally, in embodiments, the at least one coil in the spring section 62 can at least partially comprise or represent a dead coil. Fig. 9, the pitch 32 of the at least one turn is designed such that it does not constitute a dead turn, but in other embodiments, it can also be designed as a dead turn. For example, a dead turn can be present if the pitch 32 of the spring wire 18 for a full turn (360°) corresponds to twice the radius or the diameter - or even the thickness - of the spring wire 18. As in the embodiment shown here, the spring section 62 can be arranged at the end 68 of the spring 60, but can also be located at a different location if necessary. In the embodiments shown in the Fig. 7 to 9, the spring section 62 is located at the end 68 of the spring 60'. In other springs 60 according to an embodiment, however, the spring section 62 may be arranged in a different part of the spring 60. The springs 60 of the Fig. The springs 60 of the torsional vibration damper 92 shown in Figures 7 to 9 are shaped such that their force directions 66 follow a circular arc segment. However, in other embodiments, a different path may also be possible. For example, springs 60 according to one embodiment may also have a force direction 66 that always points in the same direction.

[0064] Furthermore, the elliptically shaped spring section 62 can reduce friction within the torsional vibration damper 92. The frictional torque of the torsional vibration damper 92 can be dependent on a rotational speed, since the coils are pressed into the spring channel 44 by the rotational speed-dependent centrifugal force. The frictional torque can become so great that the coils block one after the other because the frictional force between the spring coil and the spring channel 44 is correspondingly great. In such a case, it can happen that the spring coils of the spring 60 do not compress evenly. With a small twist angle of the torsional vibration damper 92 and an increased rotational speed, it can happen that only the first spring coils compress for this reason.An additional effect when retracting the last spring coil, the last spring coils or another configuration of a spring 60 according to an embodiment can be a reduction in the friction torque under speed and lower load, since the first coil or coils do not rub against the spring channel 44.

[0065] Fig. Figure 10 shows a further variant of an embodiment of a spring 60, in which the spring section 62 is also arranged at the end 68 of the spring 60. In other words, the spring 60 also has an elliptically retracted spring end. The representations of the Fig. 10a, Fig. 10b and Fig. 10c correspond to those of the Fig. 6a, Fig. 6b and Fig. 6c. In particular, Fig. 10a and Fig. 10c shows that in this variant, the elliptical shape of the spring section 62 extends by approximately 360°. This can result in greater stability depending on the arrangement of the control surfaces 56 to be controlled. In contrast to the Fig. 6a, Fig. 6b and Fig. In the variant shown in Figure 6c, the radially inner portion of end 68 of spring 60, i.e., spring section 62, can also be pushed outward. This can be useful, for example, from a manufacturing perspective.

[0066] If necessary, the stability can be further increased by choosing another variant, which is included in the Fig. 11a, Fig. 11b and Fig. 11c. Again, the representations in these Fig. 11a, Fig. 11b and Fig. 11c each of those of the Fig. 6a, Fig. 6b and Fig. 6c. In this variant, the end 68 of the spring 60 is elliptically retracted by 540°. In other words, this corresponds to one and a half turns (1.5 turns), which can further increase stability and thus operational reliability, especially under high loads on the spring 60. If the end 68 of the spring 60 is retracted very strongly inward, it may be advisable to also retract the coil behind it slightly elliptically. In other words, this can push the inner part of the second coil outward.

[0067] If a coil is retracted, a wedge force can act when the coils lock, the intensity of which depends on the load, but also on the diameter of the wire and the retraction of the end 68 of the spring. If an adjacent spring coil is also slightly retracted and thereby supports the first, the wedge force and thus the maximum tension occurring in the spring wire 18 can be reduced. Of course, two or more coils can also be retracted elliptically, for example. However, the further the spring 60 is retracted, the greater the tendency for the spring 60 to be pushed outwards by the rotational speed or the resulting centrifugal forces. This can again make the control by the hub disk 41 less favorable. On the other hand, the more springs 60 do not touch the spring channel 44 during operation, the lower the friction in the torsional vibration damper 92 becomes. It can therefore be case-specific orThe number of coils to be elliptically retracted depends on the application. As already mentioned, the spring retraction can be possible on one side or both sides.

[0068] However, the variants shown are to be understood as examples. In general, the elliptical shape of the spring section or the end 68 of the spring 60 can comprise at least 90°, as well as values ​​between the values ​​shown in the variants in Fig. 6, Fig. 10 and Fig. 11, for example 105°, 200°, 320°, 451°, etc.

[0069] The features disclosed in the above description, the following claims and the attached figures can be important and implemented both individually and in any combination for the realization of an embodiment in its various forms. Reference symbol 10 compression spring 12 spring end 13 Direction of force 14 outer diameter 16 spring axle 18 spring wire 20 final turns 21 outer diameter 22 adjacent turn 24 free end 28 spring channel 29 installation space 30 incline 32 gradient 34 grinding surface 36 large arrows 38 small arrow 40 torsional vibration dampers 41 Hub disc 44 spring channel 46 first cover plate 48 tab 50 reduced radius 52 radius 54 second cover plate 56 control surfaces 60 spring 62 spring section 64 cross-sectional area 66 Direction of force 68 End of the spring 70 Arrow 72 radius 74 second semi-axis 76 additional section 77 final turn 78 additional cross-sectional area 79 adjacent turn 80 first semi-axis 90 system 92 torsional vibration dampers 94 first component 96 second component 98 Image detail

Claims

[1] Spring (60) comprising at least one spring section (62) which, when projected onto a cross-sectional area (64) perpendicular to a force direction (66) of the spring (60) in an unloaded state thereof, extends over an arc of at least 90°, wherein the spring section (62) has an elliptical profile when projected, wherein the spring comprises an additional section (76) which, when projected onto an additional cross-sectional area (78) perpendicular to the force direction (66) of the spring (60) in the unloaded state thereof, has a circular profile, characterized by that a first semi-axis (80) of the elliptical course corresponds to a radius (72) of the circular course of the additional section (76). [2] Spring (60) according to claim 1, wherein a second semi-axis (74) of the elliptical profile is smaller than the first semi-axis (80) by a predefined value. [3] Spring (60) according to one of the preceding claims, which has turns wound from a spring wire (18), in which the spring section (62) comprises at least one turn, and in which a pitch (32) of the at least one turn in the spring section (62) is smaller than a pitch (30) of a turn outside the spring section (62). [4] Spring (60) according to claim 3, wherein the at least one turn in the spring portion (62) at least partially comprises a dead turn. [5] Spring (60) according to one of the preceding claims, wherein the spring portion (62) is arranged at one end (68) of the spring (60). [6] Spring (60) according to one of the preceding claims, wherein the force direction (66) follows a course of a circular arc segment. [7] Spring (60) according to one of the preceding claims, which comprises a further spring section (62) which, in a further projection onto a further cross-sectional area (64) perpendicular to the force direction (66) of the spring in the unloaded state thereof, extends over an arc of at least 90°, which has an elliptical shape in the further projection. [8] Spring (60) according to claim 7, wherein the spring portion (62) is arranged at one end (68) of the spring (60), and wherein the further spring portion (62) is arranged at an end (68) of the spring (60) facing away from the spring portion (62). [9] Spring (60) according to one of the preceding claims, wherein the spring (60) is ground at at least one end (68) such that a ground surface (34) is oriented substantially perpendicular to the direction of force (66) of the spring (60). [10] System (90) comprising a first component (94), a second component (96) and at least one spring (60) according to one of the preceding claims, wherein the spring portion (62) is in contact with the first component (94) and the spring (60) is mechanically coupled to the second component (96). [11] System (90) according to claim 10, wherein the first component (94) is made at least partially from a sheet-like material, and wherein the first component (94) has an edge in contact with the spring portion (62). [12] System according to one of claims 10 or 11, wherein the at least one spring (60) has a further spring section (62) which, in a further projection onto a further cross-sectional area (64) perpendicular to the direction of force (66) of the spring (60) in the unloaded state thereof, extends over an arc of at least 90°, which has an elliptical shape in the further projection, and wherein the second component (96) is in contact with the further spring section (62) with an edge. [13] System (90) according to one of claims 10 to 12, which is a torsional vibration damper (92).

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