CN115479109A

CN115479109A - Spacer element for a centrifugal pendulum with integrated disk spring

Info

Publication number: CN115479109A
Application number: CN202210665595.7A
Authority: CN
Inventors: 塞巴斯蒂安·米勒
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2021-06-16
Filing date: 2022-06-14
Publication date: 2022-12-16
Also published as: DE102021115508A1

Abstract

The invention relates to a centrifugal pendulum (1) for arrangement in a motor vehicle operated by an internal combustion engine, having at least one pendulum mass group (3) which is associated with a rotating carrier flange (2) and can perform a relative movement in conjunction with rollers along a predefined pendulum path with respect to the carrier flange (2), wherein the pendulum mass group (3) comprises two pendulum masses (4, 5) arranged on both sides of the carrier flange (2), which are spaced apart from one another and are rigidly connected via a coupling element (6), and a spacer element (8, 9) is inserted between the carrier flange (2) and each pendulum mass (4, 5), wherein two disk springs (15, 16) arranged offset from one another on the circumferential side and interacting with the pendulum masses (4, 5) are integrated in the spacer elements (8, 9) made of plastic and guided in a rotationally fixed manner on the pendulum masses (4, 5) and in a friction-fit manner on the carrier flange (2), which disk springs simultaneously surround the pendulum path (7).

Description

Spacer element for a centrifugal pendulum with integrated disk spring

Technical Field

The present application relates to a centrifugal pendulum for arrangement in a motor vehicle operated by an internal combustion engine, having at least one pendulum mass group, which is associated with a rotating carrier flange.

Background

In such a motor vehicle, a discontinuous torque is transmitted from the crankshaft to the drive train as a result of the functioning of the internal combustion engine. As a result, torsional vibrations occur, which are damped, for example, by using torsional vibration dampers designed as dual-mass flywheels, which additionally comprise a centrifugal pendulum for further damping. The vibration energy or vibration amplitude is damped or eliminated by means of the centrifugal pendulum in the following manner: the pendulum mass of the centrifugal pendulum vibrates in opposition to the vibration to be eliminated.

DE 10 2014 110 A1 discloses a centrifugal pendulum having a multi-part pendulum mass arrangement. The pendulum mass groups arranged at intervals in the circumferential direction are each formed by pendulum masses which are movably positioned on both sides of the carrier flange. The pendulum mass is here split via coupling elements which engage with play in the cutout contour of the carrier flange. The guiding of the pendulum mass is performed by means of rollers or balances which are introduced into pendulum tracks of the pendulum mass and of the support flange running opposite one another.

As a measure to avoid uncontrolled travel of the pendulum mass at the carrier plate, which adversely affects the action or the insulating capacity of the centrifugal pendulum, it is known to insert a shim plate or spacer element between the pendulum mass and the carrier plate. Such centrifugal pendulum constructions are shown, for example, in DE 10 2006 028 536 A1 and DE 10 2016 214 A1, wherein each pendulum mass group comprises two spacer elements, referred to as sliding plates, which are each placed between a pendulum mass and a carrier flange. In order to achieve a beneficial friction pairing and to prevent wear between the steel-steel pairs, it is also known from the prior art to use spacer elements or plastic clips made of plastic.

Disclosure of Invention

The object is to provide a centrifugal force pendulum with a specifically settable friction force, which is structurally and/or functionally improved, wherein the proposed measures can be implemented in a component-optimized and production-oriented manner and are simple and cost-effective for a series of designs.

This object is achieved by a centrifugal pendulum according to the invention. Advantageous embodiments are given below.

The solution of this object is that, in a spacer element made of plastic, which is secured against rotation at the pendulum mass and is guided in a friction-fitting manner at the carrier flange, two disk springs arranged offset from one another and interacting with the pendulum mass are integrated on the circumferential side, which disk springs simultaneously surround the pendulum rail in the installed state.

The spacing elements can be used to generate and/or set the frictional forces in each sector of the centrifugal force pendulum, which is formed by a pendulum mass group. Advantageously, the centrifugal pendulum thus offers the possibility of eliminating multiple steps simultaneously. This is achieved by constructing differently coordinated pendulum mass sets which respectively eliminate individual orders (Ordnung), wherein the centrifugal pendulum is also subjected to a (durchlaufen) excitation order (Erregerrdnung). In order to eliminate or damp it from the system, the centrifugal pendulum ensures constant friction. This concept thus offers the possibility of alternative or different applications of friction devices of conventional design for centrifugal pendulums, which are designed, for example, for a dual-mass flywheel in order to minimize friction.

The friction force that can be set in a targeted manner is achieved here by a special shaping of the spacer element, also referred to as a sliding plate or spacer element, which is made of plastic, and the integrated disk spring of which is inserted axially preloaded after successful installation. As a result, in the operating state, axial forces acting on the pendulum masses of the pendulum mass assembly occur, so that the desired frictional forces occur due to the friction between the plastic spacer element and the support flange. Advantageously, the disk spring offers the possibility of achieving a constant spring characteristic curve (with respect to the offset spring force) due to the range that can be set in a targeted manner. Furthermore, a characteristic curve of the disk spring is used, which is not susceptible to production tolerances and/or component tolerances of the additional component and/or the surrounding structure.

According to a preferred embodiment, the spacer plate is supported on the support flange via a large contact or friction surface. The disk spring is supported on the pendulum mass, the pretensioning of which occurs during the assembly by compression of the disk spring. The mounting height of the disk springs forming the spring windows in the normal state significantly exceeds the axial play that occurs between the pendulum mass and the support flange. The resulting force of the belleville springs is affected by the degree of bending of the spring window. The setting of the required friction force can be carried out by the dimensioning of the intermediate plate, the choice of material and/or the shaping of the disk spring.

The construction of the spacer element in one piece, comprising two disk springs, advantageously makes it possible to achieve a component-optimized centrifugal pendulum in that: the distance or spacer elements used or present hitherto are replaced by spacer elements of one piece, which are alternatively constructed and comprise a plurality of functions. A preferred embodiment provides that the disk springs are arranged at the spacer elements in the region of the pendulum track, wherein each disk spring in the installed state encloses a roller of the centrifugal pendulum, also referred to as a balance.

Advantageously, the material usage for the spacer element is almost identical with respect to hitherto conventional spacer elements. In addition, the spacer elements, which can be produced in a simple manner in terms of production and which generate friction forces in a targeted manner, can be integrated with a small amount of adjustment into an already existing pendulum mass group. The proposed measures, which are as space-neutral as possible, can thereby be implemented for a series of designs in a cost-effective manner.

According to one preferred application, the centrifugal pendulum is intended for a pulley decoupler which can be used in a traction mechanism drive, in particular a belt drive, which is excited by periodic disturbances, in order to reduce unfavorable, disturbing dynamics in the drive. In this case, the belt pulley decoupler causes the resonance occurring to be shifted into a rotational speed range below the operating rotational speed, in order to avoid, in particular, the transmission of unfavorable engine vibrations to the auxiliary unit. Advantageously, a belt pulley decoupler, which is conventional and which can also be used for a start-stop belt drive, enables a reduced belt pretensioning with reduced frictional power losses. Such a belt pulley decoupler intended for a belt drive is known, for example, from DE 10 2018 128 641 A1. Preferably, the belt pulley decoupler is suitable for a Front End Alternator Drive (Front End Alternator Drive) of an internal combustion engine.

Unlike the arrangement in a dual-mass flywheel, the centrifugal pendulum is arranged in the pulley decoupler on the primary side and thus without pre-isolation by means of a curved spring. In contrast to the centrifugal pendulum of a torsional vibration damper designed as a dual-mass flywheel, the centrifugal pendulum therefore also experiences an excitation order which requires constant friction for damping.

The centrifugal pendulum determined for belt pulley decoupler applications is characterized by high and/or different steps, which are advantageously eliminated simultaneously by means of the described concept. This is achieved by constructing differently coordinated pendulum mass groups, which in each case eliminate individual steps. Correspondingly, different frictional forces are provided for the respective sets of the pendulum mass so as to be able to experience a coordinated step without resonance. Due to the high step, the rolling or pendulum track of the roller is almost circular, so that it is expedient for the disk spring to be arranged so as to surround the pendulum track.

According to a preferred embodiment, the spacer element, which is formed in one piece and forms the base section and the two spring sections, comprises a disk spring of circular or annular design. The construction preferably comprises a disk spring integrated in the spacer element, which has a cross-sectional profile formed in a trapezoid, wherein the disk spring can be positioned corresponding to the geometric conditions. The spring force of the disk spring can be influenced and set directly by the shape of the disk spring and/or the variable dimensioning of the length, width and/or wall thickness.

This concept is proposed in particular for centrifugal pendulums, the pendulum masses of which, in combination with the associated coupling element and spacer element, are split into a structural unit of V-shaped design. In contrast, the spacer element can also be used in the form of a centrifugal pendulum having a pendulum mass arrangement different from this, such as, for example, a U-shaped design, an O-shaped design, or a centrifugal pendulum having pendulum masses positioned internally or externally.

In order to produce the spacer element made of plastic in one piece in material in a cost-effective manner, an injection molding method is preferably used. Alternatively, the spacer element can be produced by a suitable 3D printing method, for example by means of a selective laser melting method.

As material for the spacer element, a temperature-resistant, wear-resistant and durable plastic is proposed, which can furthermore be processed cost-effectively. Suitable for this purpose are, for example, thermoplastics such as: PA66GF35; PA66 CF10TF20 or PEEK, which at the same time ensures improved NVH properties at start/stop.

For the rotationally fixed and simultaneous orientation and/or azimuthal positioning of the spacer element at the pendulum mass, at least two pins of the spacer element, which are offset from one another and are also referred to as pins, engage with play in the partial recesses of the pendulum mass. The oversizing of the recess, which is preferably designed as a bore, ensures, in the operating state, on the one hand, a relative movement between the pendulum mass and the spacer element and, on the other hand, a thermally induced length change or deformation of the spacer element.

According to a further advantageous embodiment, it is provided that the spacer element is provided with a friction sleeve, which is formed in the form of a flange and which projects in a partially radial manner in the region of the spring section. This makes it possible to achieve, on the one hand, an increased contact surface or friction surface and, on the other hand, a desired improved heat dissipation.

As a measure for achieving a precise orientation of the disk spring, the spacer element furthermore comprises a connecting piece via which the orientation position of the disk spring is simultaneously set. Preferably, the web is therefore designed such that it also increases the contact surface between the carrier flange and the plastic spacer element.

A preferred embodiment also provides a material thickness of 0.6mm to 2mm for the spacer element. For spacer elements with a smaller material thickness, a harder plastic is suitable. Conversely, soft plastics are used for spacer elements with a greater material thickness. For setting the spring force, the material thickness of the spring section or of the disk spring can be designed identically or differently with respect to the basic section of the spacer element.

Drawings

In the following, the subject matter of the present application is described in detail in the five figures according to embodiments. The application is not, however, limited to the embodiments shown in the drawings. Here, it is shown schematically and/or exemplarily:

fig. 1 shows a detail of a centrifugal pendulum with a carrier flange, a pendulum mass and a spacer element;

FIG. 2 shows a view of a centrifugal pendulum with pendulum masses and spacer elements;

fig. 3 shows the spacer element in an uninstalled state;

fig. 4 shows the spacer element in the mounted state;

fig. 5 shows the characteristic course of the disk springs of the spacer element.

Detailed Description

Fig. 1 shows a detail of a rotatable centrifugal pendulum 1, which is associated, for example, with a belt pulley decoupler (not shown) or a torsional vibration damper of a motor vehicle operated by an internal combustion engine. The centrifugal force pendulum 1, in the operating state, is able to move relative to one another when rotational irregularities occur, so that a vibration damping of the pendulum mass 3 relative to the carrier flange 2 is achieved, and the effectiveness thereof is improved in combination with the belt pulley decoupling.

The centrifugal force pendulum 1 is formed by a support flange 2, which rotates about a rotational axis (not shown) and is associated, for example, with a shaft of a drive train, said flange being intended to receive a plurality of pendulum mass groups 3 arranged one behind the other in the circumferential direction. Each pendulum mass group 3 comprises two

pendulum masses

4, 5 of identical design, which are positioned on both sides of the carrier flange 2 and are connected by coupling elements 6, which are shown in fig. 2 and which are inserted with play into a cutout contour (not shown) of the carrier flange 2. Furthermore, axially elastic spacer elements 8, 9 made of plastic are provided between the support flange 2 and the rocker blocks 4, 5, respectively, which spacer elements are of uniform design and are inserted in mirror image fashion. The pendulum mass 3 is guided movably in conjunction with two rollers (not shown) which are guided in predetermined, spaced-apart pendulum paths 7 (shown in fig. 2) of the

pendulum masses

4, 5 and of the carrier flange 2.

Each spacer element 8, 9 is positioned via a

10, 11, also referred to as a bolt, on the end side, which engages with play in a

partial recess

12, 13 of the

rocker

4, 5 in order to ensure a relative movement between the spacer element 8, 9 and the

rocker

4, 5 in the operating state. The spacer elements 8, 9 comprise a base section 14 forming a contact surface and

spring sections

17, 18 comprising disk springs 15, 16, wherein the disk springs 15, 16 are preferably designed in the form of circularly designed spring windows. Each spacer element 8, 9 is designed such that its basic section 14 forms a large friction surface which interacts with the support flange 2, wherein the disk springs 15, 16 are supported with a preload at the

pendulum masses

4, 5. In the operating state, during a relative movement of the support flange 2 with respect to the pendulum mass 3, friction occurs between the spacer elements 8, 9 and the support flange 2. The installation of the spacer elements 8, 9 provides that their disk springs 15, 16 are arranged in pairs axially opposite one another, so that opposing supporting forces occur. In this case, it is intended that corresponding spring constants and/or spring characteristic curves of the disk springs 15, 16 occur which are as identical as possible. As a result, during the relative movement of the pendulum mass group 3 with respect to the support flange 2, the

pendulum masses

4, 5 are each guided in an axially aligned manner under spring bias and at a distance from one another.

In fig. 2, to further illustrate the configuration, the pendulum block group 3 is drawn without the front pendulum block 5. The two pendulum masses 4 together with the coupling element 6 and the spacer elements 8, 9 are joined together to form a structural unit, for example by means of rivets (not shown). In order to achieve an increased contact or friction surface and improved heat dissipation, the

spring sections

17, 18 have locally radially projecting, flange-

like friction sleeves

19, 20. For precise orientation, the disk springs 15, 16 are connected via connecting

webs

21, 22, which at the same time jointly increase the contact surface between the spacer elements 8, 9 and the carrier flange 2.

Fig. 3 shows a detail of the spacer element 8, so that the disk springs 15, 16 are shown in a relaxed, i.e. uninstalled, state. Here, a mounting height H occurs, which is greater than or equal to a value of twice the material thickness S of the spacer elements 8, 9. Fig. 4 shows the disk springs 15, 16 in a prestressed state after successful installation of the spacer elements 8, 9, wherein the installation height H is reduced to the magnitude of the material thickness S of the spacer elements 8, 9.

Fig. 5 shows in a line diagram a spring force profile F as a function of the installation height H of the disk springs 15, 16. In the diagram, the ordinate shows the spring force F and the abscissa shows the mounting height H. The normalized installation height is given by H1 and the installation height occurring in the installed state is given by H2. The curve shows an increase in the spring force F, wherein an almost constant characteristic curve occurs with a reduction in the installation height H of the disk spring geometry.

List of reference numerals

1. Centrifugal pendulum

2. Load-bearing flange

3. Pendulum block group

4. Swinging block

5. Swinging block

6. Coupling element

7. Swing track

8. Spacer element

9. Spacer element

10. Pin

11. Pin

12. Concave part

13. Concave part

14. Basic section

15. Disc spring

16. Disc spring

17. Spring section

18. Spring section

19. Friction sleeve

20. Friction sleeve

21. Connecting sheet

22. Connecting sheet

F spring force curve

H installation height

Thickness of S material

Claims

1. A centrifugal pendulum (1) for arrangement in a motor vehicle operated by an internal combustion engine, having at least one pendulum mass group (3) which is associated with a rotating carrier flange (2) and can perform a relative movement along a predefined pendulum path in conjunction with rollers relative to the carrier flange (2), wherein the pendulum mass group (3) comprises two pendulum masses (4, 5) which are arranged on both sides of the carrier flange (2) and which are spaced apart from one another and are rigidly connected via a coupling element (6) and between the carrier flange (2) and each pendulum mass (4, 5) a spacer element (8, 9) is inserted,

it is characterized in that the preparation method is characterized in that,

two disk springs (15, 16) which are arranged offset to one another on the circumferential side and interact with the pendulum masses (4, 5) and which simultaneously enclose the pendulum rail (7) are integrated into spacer elements (8, 9) which are made of plastic, are secured against rotation at the pendulum masses (4, 5) and are guided in a friction-fit manner at the carrier flange (2).

2. Centrifugal pendulum (1) according to claim 1,

it is characterized in that the preparation method is characterized in that,

the spacer elements (8, 9) are associated with a centrifugal pendulum (1) designed for use in a belt pulley decoupler.

3. Centrifugal pendulum (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the disk springs (15, 16) form circular spring sections (17, 18) which project from the spacer elements (8, 9).

4. Centrifugal pendulum (1) of one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the pendulum masses (4, 5) together with the coupling element (6) and the spacer elements (8, 9) are joined together to form a pendulum mass group (3) which is arranged in a V-shaped design.

5. Centrifugal pendulum (1) of one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the spacer elements (8, 9) which are produced in one piece from plastic are produced by an injection molding method.

6. Centrifugal pendulum (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the spacer elements (8, 9) are made of a temperature-resistant, wear-resistant thermoplastic, such as PA66GF35; PA66 CF10TF20 or PEEK.

7. Centrifugal pendulum (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

for the purpose of orientation, the spacer element (8, 9) comprises at least two pins (10, 11) which are offset from one another and engage with play in local recesses (12, 13) of the pendulum masses (4, 5).

8. Centrifugal pendulum (1) of one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the spring section (17, 18) of the spacer element (8, 9) comprises a radially projecting friction sleeve (19, 20) in some regions.

9. Centrifugal pendulum (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the spring sections (17, 18) of the spacer elements (8, 9) are connected via connecting pieces (21, 22).

10. Centrifugal pendulum (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

for the spacer elements (8, 9), a material thickness S of ≦ 6mm is provided, wherein the material thickness of the disk springs (15, 16) is designed identically or differently to the basic section (14).