WO2016012016A1

WO2016012016A1 - Centrifugal pendulum and drive system having a centrifugal pendulum

Info

Publication number: WO2016012016A1
Application number: PCT/DE2015/200396
Authority: WO
Inventors: Stephan Maienschein
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2014-07-24
Filing date: 2015-06-25
Publication date: 2016-01-28
Also published as: EP3172460A1; DE102014214534A1; DE112015003416A5

Abstract

The invention relates to a centrifugal pendulum (100) having a pendulum flange (120) that can be rotated about an axis of rotation (x) and coupled to a drive train, and at least one pendulum mass coupled to the pendulum flange via at least one guide element (130) such that it can be moved in the circumferential direction (U). The guide element is guided through the pendulum mass (110) and cutouts (112, 122) assigned to the pendulum flange in a manner complementary thereto. At least one first cutout is bounded by a cutout contour (131) which has at least two arcuate segments (133, 134) merging into each other; wherein the cutout contour, in conjunction with the guide element, is designed to guide the pendulum mass along a pendulum path. In a neutral position of the pendulum mass, at the point at which the guide element is in contact with a cutout contour, a contact point is defined; in addition, a tangent to the cutout contour at the contact point defines a Y axis. A projection of the cutout contour onto the Y axis defines a projection area which is bounded by two bounding points, one of which is at a first distance and another of which is at a second distance from the contact point. The point on the cutout contour the projection of which onto the Y axis is at the first distance (A1) from the contact point (P) is a first end position point (E1), and the point on the cutout contour the projection of which onto the Y axis is at the second distance (A2) from the contact point is a second end position point (E2). The at least two arcuate segments that merge into each other are arranged asymmetrically in such a way that, in a neutral position of the pendulum mass, the first distance A1 and the second distance A2 have an unequal distance ratio A1/A2, i.e. a ratio A1/A2 which is not equal to 1.

Description

Centrifugal pendulum and drive system with centrifugal pendulum

The invention relates to a centrifugal pendulum for a drive train of a motor vehicle and a drive system with such a centrifugal pendulum, wherein the centrifugal pendulum least one pendulum mass and coupled to the drive train pendulum comprises, and wherein the pendulum mass on the pendulum to perform a predefined pendulum motion movable with the pendulum - is coupled.

Generic centrifugal pendulum pendulum are preferably in drive trains of motor vehicles for the isolation of torsional vibrations, which are introduced by an internal combustion engine, such as a diesel engine, the registered drive torque superimposed introduced into the drive train, alone or in conjunction with torsional vibration dampers such as dual mass flywheels from the prior art. As a rule, waves of periodically operating machines, eg. B. on a crankshaft of an internal combustion engine of a motor vehicle, in a rotational movement of the shaft superimposed torsional vibrations, wherein the frequency changes with a speed of the shaft. By combustion processes of the internal combustion engine torsional vibrations in the drive train of the motor vehicle are excited in particular in the train operation. To reduce these torsional vibrations, a centrifugal pendulum can be provided, which can eliminate torsional vibrations over a larger speed range of the internal combustion engine, ideally over its entire speed range.

A centrifugal pendulum usually comprises a plurality of movably mounted pendulum masses which are suspended between guide elements on a rotating pendulum and can perform along predetermined treads a relative movement to this pendulum to thereby occupy a variable distance from the axis of rotation of the pendulum can. As a result of the torsional vibrations in the drive train, the pendulum masses to commute or Swinging excited, with their focal points permanently and time-shifted change to the torsional vibrations in the drive train, which causes a damping of the torsional vibrations by a mechanical feedback. Efficient damping can be achieved by appropriate tuning of the pendulum masses and their guide tracks, the pendulum tracks typically being symmetrical.

It proves to be disadvantageous that the movements of the pendulum masses are unfavorable with regard to the utilization of the available installation space, since in certain operating states of the centrifugal pendulum mass, the pendulum masses abut against the pendulum flange, a collision of the circumferentially adjacent end faces of the pendulum masses and / or or an abutment of the guide elements in the respective longitudinal ends of the running surfaces of the pendulum flange and / or the pendulum masses can occur, whereby malfunction of the centrifugal pendulum, but especially noise is caused. Stop elements are only partially used in centrifugal pendulum with trapezoidal arrangement of the pendulum masses, so that in particular the frontal ends of the pendulum masses must be adjusted radially or circumferentially accordingly to prevent a collision of the pendulum masses as far as possible. This leads to an undesirable reduction in the total mass of the pendulum masses, which in turn reduces the generatable restoring moment during a deflection of the centrifugal pendulum during rotation.

It is an object of the invention to provide a centrifugal pendulum for a drive train of a motor vehicle with improved vibration damping and / or an optimized movement of the pendulum masses, in particular with regard to an improved utilization of the available installation space.

This object is achieved by means of a centrifugal pendulum according to claim 1. Advantageous embodiments are given in the dependent claims.

According to the invention, it has been recognized that an improved centrifugal pendulum for a drive train of a motor vehicle can be provided by virtue of the fact that the centrifugal pendulum swivelable about an axis of rotation x and with the drive strand coupled coupling pendulum and at least one circumferentially movable with the pendulum via at least one guide element coupled pendulum mass comprises. The guide element is guided by the pendulum mass and complementary to the pendulum flange associated recesses. At least one first recess is bounded by a recess contour, which has at least two arcuate segments merging into one another; wherein the recess contour is formed in connection with the guide element to guide the pendulum mass along a pendulum track. In a neutral position of the pendulum mass, a contact point is defined at the point at which the guide element is in contact with the recess contour, with a tangent to the recess contour also defining a y-axis at the contact point. A projection of the recess contour on the y-axis defines a projection area bounded by two boundary points, one of which has a first distance and another a second distance to the contact point. In this case, the point on the recess contour whose projection on the y-axis has the first distance to the contact point P, a first Endlagenpunkt E1, and the point on the recess contour whose projection on the y-axis has the second distance to the contact point, a second end position E2. The at least two arcuate segments which merge into one another are arranged asymmetrically in such a way that, in a neutral position of the pendulum mass, the first distance A1 and the second distance A2 have an unequal distance ratio A1 / A2, ie a quotient A1 / A2 which is not equal to one. According to the invention causes the deviating from a circular arc asymmetric arrangement of the segments at the same pulling and thrust direction tilt angle of the pendulum mass, among other things, a balance of unequal loading of the recess contour. Due to the simultaneously existing radial portion of the pendulum motion can by the

Asymmetry striking the guide element to the end position points of the recess contour can be avoided reduced by the recess contour is designed at least partially asymmetrical. In principle, two pendulum masses can be arranged opposite one another on both sides of the pendulum flange, wherein these two pendulum masses can advantageously be firmly connected to one another. In a further embodiment, at least one pendulum mass can be arranged on the outside of a section of the pendulum be arranged flange, wherein in a further alternative embodiment, the at least one pendulum mass can be movably arranged between two opposite portions of the pendulum, so that in each case a pendulum mass is arranged internally between two sections of the pendulum. It has proven to be particularly advantageous if the distance ratio A1 / A2 between 0.2 <A1 / A2 <1 or 1 <A1 / A2 <4.2; in particular between 0.25 <A1 / A2 <1 or 1 <A1 / A2 <4.25.

In another embodiment, in the neutral position of the pendulum mass, a center of gravity axis sz, which is perpendicular to the axis of rotation x, is also perpendicular to the y-axis passing through the contact point P. A z-axis is at the contact point P perpendicular to the y-axis. In a particularly preferred embodiment, in a neutral position, the z-axis passing through the contact point runs parallel to the center of gravity axis sz.

A projection of the first end position point E1 on the z axis has a third distance A3 to the contact point P, and a projection of the second end position point E2 on the z axis has a fourth distance A4 to the contact point K, wherein in the neutral position of the pendulum mass of the third distance A3 and the fourth distance A4 have an uneven distance ratio A3 / A4, ie a quotient A3 / A4 which is not equal to 1. According to an advantageous embodiment, the distance ratio (A3 / A4) is between 0.2 <A3 / A4 <1 or 1 <A3 / A4 <4.2; in particular between 0.25 <A3 / A4 <1 or 1 <A3 / A4 <4.25. Furthermore, it is advantageous if the radii of the first segment and of the second segment are of different sizes, wherein in a preferred embodiment the radius of the first segment is smaller than the radius of the second segment. A transition point of the arcuate segments can be arranged at the maximum radial deflection of the pendulum masses relative to the receiving part. By changing the radii can be ensured that the spring element is braced by the first segment along the pendulum track so that the pendulum speed of the pendulum mass decelerated along the pendulum and / or the pendulum mass can be returned to the second segment. According to an advantageous embodiment, a plurality of pendulum masses are provided with a plurality of recesses and a plurality of guide elements in a centrifugal pendulum. In principle, four or six pendulum masses can be uniformly distributed over the circumference. Alternatively, with respect to the pendulum flange plane, two mutually opposite pendulum masses can form a pendulum mass pair, which are each connected to one another, wherein a guide element rolls in each case into the associated recess contours of the two pendulum masses and the pendulum flange. Particularly advantageous is the use of a four-part distribution of four distributed over the circumference pendulum mass pairs, each with four pendulum masses per pendulum mass side proved.

Due to the asymmetrical design of the two segments of the recess contour, it is possible to determine the rest position of the guide element. Furthermore, a collision of the pendulum masses can be avoided, so that the centrifugal pendulum is particularly quiet in operation. The pendulum mass is forcibly guided in standstill of the drive train in a predefined rest position.

Furthermore, it has proven to be advantageous if the outer circumference of the pendulum masses has a smaller radius than the radius of the pendulum flange. The radius of the pendulum masses is dimensioned such that the pendulum masses remain radially within a pendulum flange during a pendulum movement, so that the radial space is predetermined solely by the outer radius of the pendulum flange.

In principle, the inner radius of the pendulum masses can also be adjusted to an inner radius predetermined by space specifications, which is not undershot during a pendulum movement of the pendulum masses.

In the proposed centrifugal pendulum, it has proved to be advantageous if the pendulum movement of the pendulum mass relative to the pendulum results in a bifilar pendulum motion, the alignment of the pendulum tracks of a pendulum mass or pendulum mass pair is done in such a way that it is not a single pendulum point with a given thread - Pendulum or commute, but are suspended at two pendulum points. Due to the asymmetrical arrangement of the segments, it is possible to avoid hitting the pendulum masses together. be, so that the centrifugal pendulum is particularly quiet in operation, whereby the centrifugal pendulum has a particularly good performance.

The object of the invention is also achieved by a drive system for a motor vehicle with an internal combustion engine and a centrifugal pendulum according to the invention according to claim 1 1, wherein the internal combustion engine is coupled via a drive train with the centrifugal pendulum. According to the invention, it has been recognized that an improved drive system for a motor vehicle can be provided in that the motor vehicle comprises an internal combustion engine and a centrifugal pendulum. The combustion engine is coupled to the centrifugal pendulum. In this way, a particularly quiet and fuel-efficient working drive system can be provided, which allows a particularly high ride comfort.

Other features, applications and advantages of the invention will become apparent from the following description of the embodiment of the invention, which is illustrated in the drawing. It should be noted that the features described or illustrated in the figures, alone or in any combination, the subject matter of the invention, regardless of their combination in the claims or their dependency and regardless of their formulation or representation in the description or in the drawing has only a descriptive character and is not intended to limit the invention in any way.

The invention will be explained in more detail with reference to figures. The same components are named with the same reference numerals. Showing:

Figure 1 is a schematic sectional view of a known from the prior art centrifugal pendulum; Figure 2 is a schematic detail view of a section of a pendulum mass of a centrifugal pendulum according to the invention; and 3 shows a schematic detail view of a pendulum mass of a centrifugal pendulum according to the invention.

To reduce torsional vibrations, additional masses are applied to a rotating part of the torsional vibration system. Such a known from the prior art centrifugal pendulum 100 can be seen in the figure 1. Therein four pendulum masses 1 10 are attached to a pendulum 120. The pendulum masses 1 10 have recesses 1 12 for guide elements 130. The pendulum flange 120 has a disc-shaped configuration and also has recesses 122 for the guide elements 130. The recesses 1 12, 122 in the pendulum masses 1 10 and the pendulum 120 each form a recess contour 131, which in turn each two arcuate segments 133 merging into one another , 134. The recess contour 131 is formed in conjunction with the guide elements 130 such that the pendulum mass 1 10 can be guided along a pendulum track. In this case, the guide elements 130 run in operation in the pendulum 120 due to the centrifugal force at the radially outer edge of the pendulum 120th

The pendulum masses 1 10 are subject during operation of a centrifugal acceleration and thus perform vibrations on the predetermined recess contours 131 when they are excited by Drehzahlunguniformities. Due to these vibrations, the exciter oscillation is deprived of energy at appropriate times and supplied again, so that the excitation oscillation is settled and the centrifugal pendulum pendulum 100 acts as a vibration damper. Since both the natural frequency of the centrifugal pendulum oscillation and the excitation frequency are proportional to the speed, the damping effect of a centrifugal pendulum 100 over the entire frequency range can be achieved. Prerequisite for a satisfactory Tilgerwirkung is in addition to the coordination of effective radius and pendulum length a minimum mass of pendulum masses 1 10 and a sufficient swing angle. Since noises are produced in the pendulum flange 120 when the guide elements 130 strike the two ends 123, 124 of the recess contour 131, the recess contour 131 of at least one recess 130 according to the present invention, as shown in FIGS. 2 and 3, is designed accordingly. The pendulum flange 120 has substantially the shape of a circular disk. In the figure 1 it can be clearly seen that four pendulum masses 1 10 are distributed radially outside evenly distributed over the circumference of the pendulum 120. Here, the number of pendulum masses 1 10 depending on the embodiment of the centrifugal pendulum 100 vary, usually the pendulum masses 1 10 by means of spacers or spacers (not shown) are attached in pairs to each other. Alternatively, at least one pendulum mass may be outboard. In an advantageous embodiment, the pendulum mass is such movably guided between two opposite sections of the pendulum, that in each case a pendulum mass is arranged internally between sections of the pendulum.

The movement of the pendulum mass 1 10 is made possible by the guide elements 130 which are guided in recesses 1 12 of the associated pendulum mass 1 10. The recesses 12 are formed by through holes which extend in the axial direction through the pendulum mass 11 and have the shape of elongated tubes which are curved in the shape of a kidney. The recesses 122 for receiving the guide elements 130 in the pendulum flange 120 of the centrifugal pendulum 100 are also formed kidney-shaped curved. The guide elements 130 serve to limit the movement of the pendulum mass 1 10 in the plane of the drawing, ie in the radial direction and in the circumferential direction U and define. In principle, the pendulum masses 1 10 execute a translatory movement relative to the pendulum flange 120 in such a suspension. This is achieved in the illustrated embodiment by a so-called parallel bifilar suspension bearing the pendulum mass 1 10 by means of the paraxial guide elements 130, wherein the operating principle and structure of the bifilar suspended centrifugal pendulum 100 is well known in the prior art, so that at this point for the sake of brevity, the description will not be discussed further.

As shown in detail in FIG. 2 on a section of a pendulum mass of a centrifugal pendulum pendulum according to the invention, the recess contour 131 of this first recess 12 has two circularly arcuate segments 133, 134 merging into one another in an arc shape. Basically, the recess contour 131 is formed in conjunction with the guide element 130, the pendulum mass 1 10 along to lead a cable car. In the pendulum movement of the pendulum mass 1 10, the pendulum mass 1 10 is moved from the second segment 134 in the first segment 133, wherein the different radii of the two segments 133, 134 are coordinated such that a pendulum speed of the pendulum mass 1 10 along the Retarded recess 131 and the pendulum mass 1 10 is returned to the neutral position. In this neutral position of the pendulum mass 1 10, a contact point P is defined at the point at which the guide element 130 is in contact with the recess contour 131. Further, a tangent to the recess contour 131 defines a y-axis at the contact point P. Accordingly, a projection of the recess contour 131 on the y-axis may define a projection area, wherein the projection area is limited by two boundary points. These two boundary points have a first distance A1 and a second distance A2 to the contact point P, wherein the point on the recess contour 131 whose projection on the y-axis provides the first boundary point a first end position point E1, and the point on the recess contour 131, the Projection on the y-axis provides the second boundary point, a second Endlagenpunkt E2 is. The at least two arcuate segments 133, 134 merging into one another are arranged asymmetrically in such a way that in a neutral position of the pendulum mass the first distance A1 and the second distance A2 have a distance ratio A1 / A2 which is not equal to one.

Advantageously, the two arcuate segments 133, 134 have different radii, wherein in the illustrated embodiment, the first segment 133 has a smaller radius than the second segment 133, whereby the guide member 130 is forced into a neutral position shown, as soon as no centrifugal forces on the Centrifugal pendulum 100 act, or the pendulum speed along the recess contour 131 is braked. In principle, the arcuate segments 133, 134 of the cutout contour 131 can be designed in such a way that the positively driven rest position of the guide element 130 can be arranged in any desired area of the cutout contour 131. In this case, a transition point of the arcuate segments 133, 134 can be arranged at the maximum deflection of the pendulum mass 1 10 relative to the pendulum flange 120. According to the invention causes the deviating from a circular segment-shaped asymmetric Arrangement of the segments 133, 134 in the same direction of tension and thrust direction tilt angle of the pendulum mass 1 10 inter alia, a compensation of the unequal loading of the recess contour 131st As a result of the simultaneously existing radial portion of the pendulum movement, a striking of the guide element to the end position points of the recess contour can be reduced by the asymmetry. It has proven to be particularly advantageous if the distance ratio A1 / A2 between 0.2 <A1 / A2 <1 or 1 <A1 / A2 <4.2; in particular between 0.25 <A1 / A2 <1 or 1 <A1 / A2 <4.25.

In the neutral position of the pendulum mass 1 10 is a gravity axis sz, which is in the pivot point S of the pendulum mass perpendicular to the axis of rotation x, also perpendicular to the passing through the contact point P y-axis, wherein a z-axis is defined such that in the Contact point P is perpendicular to the y-axis. As can be seen from the figure, the geometry of the arrangement is chosen so that in the illustrated neutral position the z-axis passing through the contact point K runs parallel to the center of gravity axis sz.

A projection of the first Endlagenpunktes E1 on the z-axis has a third distance A3 to the contact point P, and a projection of the second Endlagenpunktes E2 on the z-axis has a fourth distance A4 to the contact point P, wherein in the neutral position of the pendulum mass 1 10 of third distance A3 and the fourth distance A4 have a stand-off ratio A3 / A4, which is not equal to 1. It has proven to be particularly advantageous if the distance ratio (A3 / A4) between 0.2 <A3 / A4 <1 or 1 <A3 / A4 <4.2; especially between 0.25 <A3 / A4 <1 or 1 <A3 / A4 <4.25.

FIG. 3 shows a schematic detail view of a centrifugal pendulum 100 according to the invention. The pendulum mass 1 10 has therein two recesses 1 12, which are mirrored at the axis of rotation x and a center of gravity S of the pendulum mass extending axis of gravity sz. The recess contours 131 are determined by the arcuate first segment 133 and the arcuate second segment 134. In the process, the recess contour 131 flattens off from the first segment 133 to the second segment 134, so that a continuous overlap from a smaller radius to a larger radius. As a result of the co-existing radial component of the oscillating movement an abutment of the guide elements 130 may be at the recessed contour 131 limiting Endlagenpunkte L E1, E2 _L, _R E1, E2 _R largely reduced by the asymmetry. Basically, the present invention allows the total mass of the pendulum mass 1 10 further increases, whereby the repayment effect of the centrifugal pendulum 100 can be increased.

In addition to the described and illustrated embodiments, further embodiments are conceivable which may include further modifications and combinations of features.

LIST OF REFERENCE NUMBERS

100 centrifugal pendulum

1 10 first pendulum mass

120 pendulum flange

1 12 second recess on the pendulum mass

122 first recess on the pendulum flange

130 guide element

131 recess contour

133 first segment

134 second segment

U circumferential direction

X rotation axis

S center of gravity pendulum mass

sz center of gravity pendulum mass y axis

z axis

P contact point

E1 end position point

E2 end position point

A1 first distance

A2 second distance

A3 third distance

A4 fourth distance

Claims

claims

Centrifugal pendulum (100) for a drive train of a motor vehicle, with

at least one pendulum flange (120) rotatable about an axis of rotation (x) and coupleable to the drive train, at least one pendulum mass (110) movably coupled to the pendulum flange (120) via at least one guide element (130) in circumferential direction (U), in which

- The guide element (130) by the pendulum mass (1 10) and complementary to the pendulum (120) associated recesses (1 12, 122) is guided; in which

- At least a first recess (1 12) is bounded by a recess contour (131) having at least two arcuate segments (133, 134) merging into one another; in which

- The recess contour (131) in connection with the guide element (130) is adapted to guide the pendulum mass (1 10) along a pendulum track; in which

- At the point at which the guide element (130) in a neutral position of the pendulum mass (1 10) with the recess contour (131) makes contact, a contact point (P) is defined,

- defines a tangent to the recess contour (131) at the contact point (P) a y-axis, wherein

the projection of the cutout contour (131) on the y-axis defines a projection area bounded by two boundary points, one of which has a first distance (A1) and another a second distance (A2) to the contact point (P); in which

- The point on the recess contour (131) whose projection on the y-axis has the first distance (A1) to the contact point (P), a first Endlagenpunkt (E1), and the point on the recess contour (131), its projection on the y-axis has the second distance (A2) to the contact point (P), a second Endlagenpunkt (E2) is; in which

- The at least two merging arcuate segments (133, 134) are arranged asymmetrically such that in a neutral position the pendulum mass (1 10) of the first distance (A1) and the second distance (A2) have a distance ratio (A1 / A2) not equal to 1.

Second centrifugal pendulum (100) according to claim 1, wherein at least one pendulum mass (1 10) between two opposite portions of the pendulum (120) is arranged to be movable.

3. Centrifugal pendulum (100) according to claim 1 or 2, wherein the distance ratio (A1 / A2) between 0.2 <A1 / A2 <1 or 1 <A1 / A2 <4.2; in particular between 0.25 <A1 / A2 <1 or 1 <A1 / A2 <4.25.

4. centrifugal pendulum (100) according to one of claims 1 to 3, wherein in the neutral position of the pendulum mass (1 10) has a gravity axis (sz), which is perpendicular to the axis of rotation (x), also perpendicular to the by the contact point (P) extending y-axis is.

5. centrifugal pendulum (100) according to one of claims 1 to 4, wherein further a z-axis is defined, which is perpendicular to the contact point (P) on the y-axis.

6. centrifugal pendulum (100) according to claim 5, wherein in a neutral position of the pendulum mass (1 10) through the contact point (P) extending z-axis parallel to the axis of gravity axis (sz).

7. centrifugal pendulum (100) according to any one of claims 5 or 6, wherein a projection of the first Endlagenpunktes (E1) on the z-axis a third distance (A3) to the contact point (P) and a projection of the second Endlagenpunktes (E2) on the Z axis has a fourth distance (A4) to the contact point (P), wherein in the neutral position of the pendulum mass (1 10) the third distance (A3) and the fourth distance (A4) have a distance ratio (A3 / A4) not equal to 1.

8. A centrifugal pendulum (100) according to claim 7, wherein the distance ratio (A3 / A4) between 0.2 <A3 / A4 <1 or 1 <A3 / A4 <4.2; especially between 0.25 <A3 / A4 <1 or 1 <A3 / A4 <4.25.

9. centrifugal pendulum (100) according to one of claims 1 to 8, wherein the radii of the first segment (133) and the second segment (134) are different in size.

10. centrifugal pendulum (100) according to one of claims 1 to 9, wherein the radius of the first segment (133) is smaller than the radius of the second segment (134).

1 1. Centrifugal pendulum (100) according to one of claims 1 to 10, wherein a plurality of pendulum masses (1 10) having a plurality of recesses (1 12) and a plurality of guide elements (130) are provided, which according to one of claims 1 to 9 executed are.

12. Drive system for a motor vehicle with an internal combustion engine and a centrifugal pendulum (100), wherein the internal combustion engine via a drive train with the centrifugal pendulum (100) is coupled, wherein the centrifugal pendulum (100) is designed according to one of claims 1 to 1 1.