Method for manufacturing a centrifugal pendulum and centrifugal pendulum

Abstract

Method for manufacturing a centrifugal pendulum (1) with pendulum components (13, 14, 14a, 14b, 14c) made of sheet metal, namely a pendulum mass carrier (2) arranged about an axis of rotation (d) and pendulum masses (3, 3a, 3b, 3c) arranged around its circumference to allow it to oscillate, characterized in that at least one stamped blank (9, 9a, 9b, 9c) is manufactured with at least two of the pendulum components (13, 14, 14a, 14b, 14c) and the pendulum components (13, 14, 14a, 14b, 14c) are subsequently separated, wherein the pendulum mass carrier (2) has recesses (4) in which the pendulum masses (3, 3a, 3b, 3c) are received, wherein at least one predetermined breaking point (10) is provided between each pendulum mass (3, 3a, 3b, 3c) and the pendulum mass carrier (2) is provided.

Description

[0001] The invention relates to a method for manufacturing a centrifugal pendulum. Centrifugal pendulums are used, in particular in the drive trains of motor vehicles with high-speed internal combustion engines, for torsional vibration isolation. For this purpose, the centrifugal pendulum has a pendulum mass carrier rotatably arranged about an axis of rotation, for example, the axis of rotation of the crankshaft of the internal combustion engine. Pendulum masses are distributed around the circumference of the pendulum mass carrier and are predefined by means of pendulum bearings. When the pendulum mass carrier rotates, the pendulum masses are accelerated radially outwards and can be displaced along a predefined pendulum path by means of the pendulum bearings. This allows them to shift to smaller radii against the effect of the centrifugal force when torsional vibrations occur, thus dampening the torsional vibrations in a speed-adaptive manner.

[0002] A typical arrangement of pendulum masses on a pendulum mass carrier is known from DE 10 2009 021 355 A1. In this arrangement, pendulum mass components are arranged on both sides of the pendulum mass carrier and are connected to the pendulum masses by means of connecting elements passing through recesses in the pendulum mass carrier. The pendulum masses are mounted to the pendulum mass carrier by means of two circumferentially spaced pendulum bearings, each consisting of axially adjacent raceways in the pendulum mass components and in the pendulum mass carrier. A pendulum roller, passing through recesses in the raceways, rolls on these raceways. Furthermore, as is known, for example, from WO 2014 / 082 629 A1, pendulum masses can be arranged axially between two side parts that form the pendulum mass carrier, distributed around the circumference.

[0003] From DE 10 2009 042 812 A1, a centrifugal pendulum integrated into a dual-mass flywheel is known, which, among other things, discloses pendulum masses housed in cutouts of a pendulum mass support. The pendulum masses are supported by pendulum rollers that roll on radially superimposed raceways of the pendulum masses and the pendulum mass support, so that the pendulum masses are housed within the installation space of the pendulum mass support. If the axial extension of the pendulum masses is limited to the thickness of the pendulum mass support, the mass of the pendulum mass is not very effective for damping torsional vibrations.

[0004] DE 10 2013 214 829 A1 discloses a centrifugal pendulum with pendulum masses housed in recesses of the pendulum mass carrier and pendulum bearings with radially superimposed raceways. The pendulum masses are axially supported by retaining plates, which are arranged either on the pendulum mass carrier or on the pendulum masses themselves. If the retaining plates are attached to the pendulum masses at all, they do not contribute significantly to the mass of the pendulum masses.

[0005] The proposed centrifugal pendulums are preferably manufactured using stamping and, if necessary, stamping forming processes. In this process, the pendulum mass carrier and the pendulum masses are produced, where possible, while minimizing stamping scrap and reducing tooling costs, for example, by producing several pendulum masses individually from a sheet metal blank using a single stamping tool.

[0006] Further reference is made to DE 10 2012 212 895 A1 and DE 10 2012 213 124 A1 as prior art.

[0007] The object of the invention is to further develop a method for manufacturing a centrifugal pendulum, thereby reducing tooling and unit costs. Furthermore, the invention aims to simplify the hardening process for the pendulum masses or the pendulum mass carrier.

[0008] The problem is solved by the subject matter of claim 1. The dependent claims describe advantageous embodiments of the subject matter of claim 1.

[0009] The proposed method is for manufacturing a pendulum pendulum made of sheet metal components. The pendulum components are produced, for example, from sheet metal strips, so-called coils of rolled sheet metal, using a stamping / forming process in a single- or multi-stage stamping and forming process. The pendulum components may, in addition to other sheet metal parts, form a pendulum mass carrier arranged around a rotational axis, as well as pendulum masses distributed around the circumference of the pendulum mass carrier and mounted on it in a way that allows it to oscillate. The centrifugal pendulum can have a pendulum mass carrier designed as a pendulum flange with pendulum masses arranged laterally. Alternatively, the pendulum mass carrier can be formed from two spaced-apart side parts, between which the pendulum masses are mounted.Alternatively, the pendulum mass support can be designed as a pendulum flange with recesses, in which the pendulum masses are accommodated in the plane of the pendulum flange. The pendulum masses have essentially the same thickness as the pendulum mass support, thus enabling the use of particularly narrow centrifugal pendulums.

[0010] The process is carried out by producing at least one stamped blank containing at least two of the pendulum components, and then separating the pendulum components. For example, a blank containing the pendulum mass carrier and the pendulum masses can be produced from sheet metal. The pendulum masses are directly accommodated in recesses dimensioned to allow them to move along a predetermined oscillation angle of the pendulum mass carrier. Therefore, only the areas required for the oscillation angle are stamped out of the blank, so that the pendulum masses are already contained within the recesses of the pendulum mass carrier. This allows the pendulum mass carrier and the pendulum masses to be produced using a single stamping tool. This, along with the reduced stamping waste, enables the production of a particularly cost-effective centrifugal pendulum.

[0011] It has proven advantageous if the raw part is designed such that the pendulum mass carrier and the pendulum masses are formed in one piece, so that the pendulum masses are precisely fixed in the recesses at least until the centrifugal pendulum is assembled. At a predetermined time, the pendulum mass carrier and the pendulum masses are then separated to ensure the centrifugal pendulum functions as intended.

[0012] In an alternative embodiment of the method, multiple pendulum masses can be manufactured in a single piece within a common blank and subsequently separated. For example, the pendulum masses can be directly connected to one another by means of one or more predetermined breaking points.

[0013] Alternatively, a support element can be provided in which the pendulum masses are received by means of predetermined breaking points. For example, a support element can be provided in which some or all of the pendulum masses are connected by means of at least one predetermined breaking point. For example, an annular support element can be provided in which pendulum masses are received on the inner circumference, distributed around the circumference, by means of at least one, preferably two, predetermined breaking points spaced apart in the circumferential direction. Alternatively, a support element can be provided which receives at least two radially opposite or more than two pendulum masses distributed around the circumference on the outer circumference by means of at least one predetermined breaking point.

[0014] According to a further alternative embodiment of the method, a raw part can be provided with a support part on which at least two pendulum masses are held at least at one circumferential end by means of a predetermined breaking point. The pendulum masses can, for example, be arranged stacked one above the other in the same plane and in the same orientation and each be connected at its circumferential end to a support part by means of a predetermined breaking point.

[0015] The raw part can be manufactured by means of a stamping process, optionally incorporating forming steps, for example, to create embossing to prevent burrs or the like. According to the invention, at least one predetermined breaking point is provided between the pendulum mass carrier and the pendulum masses, or between several pendulum masses, or between a carrier part and the pendulum masses. The predetermined breaking point can be created, for example, by weakening the material, such as by embossing.Should pendulum mass carriers and / or pendulum masses require a shape deviating from the flat form defined by the sheet metal blank, a stamping forming process may be employed, for example, to axially adapt the pendulum flange to predefined installation configurations, to form a flange or similar feature, to create tabs or similar elements, and / or to stamp functional elements such as rivet lugs or similar features. For instance, the pendulum masses can be manufactured by forming processes such as transverse extrusion, material folding, or similar techniques, thereby increasing the axial thickness of the pendulum masses to increase their mass.

[0016] Because the blank, which is only later separated into the pendulum mass carrier and the pendulum masses, or into the individual pendulum masses, can be hardened as a whole. This means that the blank is hardened as a whole after stamping, for example, by surface hardening, and then separated. Further processing steps such as coating, painting, polishing, and / or the like can be carried out on the blank as a whole.

[0017] Preferably, raceways are machined onto the pendulum mass carrier and the pendulum masses using a tooling process. In conjunction with pendulum rollers rolling on these raceways, each raceway forms a pendulum bearing. To create a bifilar suspension of the pendulum masses, which are arranged to oscillate in a pendulum plane perpendicular to the axis of rotation within the centrifugal force field of the rotating pendulum mass carrier, it has proven advantageous to design each pendulum mass by means of two pendulum bearings spaced apart circumferentially. In one embodiment of the centrifugal pendulum, the radially outer raceways of the pendulum mass carrier are essentially opposite the radially inner raceways of the pendulum mass of each pendulum bearing.In further embodiments, the pendulum masses are arranged axially spaced from the pendulum mass carrier, and the pendulum rollers axially overlap the raceways of the pendulum mass carrier and the pendulum masses, supporting them against the centrifugal force by forming a three-point bearing consisting of two side parts forming the pendulum mass carrier and a pendulum mass or a pendulum flange and two pendulum masses arranged on either side of it. A predetermined breaking point can preferably be provided centrally in the circumferential direction between the pendulum bearings. Alternatively, several predetermined breaking points distributed around the circumference can be provided for each pendulum mass on the inner circumference, the outer circumference, and / or on the side surfaces such as the circumferential ends of the pendulum masses and, if necessary, at opposite positions of the pendulum mass carrier.

[0018] The spaces between the raceways of a pendulum bearing can be designed so that the pendulum rollers can be inserted before the pendulum mass carrier and the pendulum masses are separated. At least one predetermined breaking point between the pendulum masses and the pendulum mass carrier can be provided during the insertion of the pendulum rollers. Any interfering burrs or protrusions can be removed by machining, laser cutting, or other means. Alternatively, the spaces between the raceways of the pendulum mass carrier and the pendulum masses can be designed with a smaller diameter than the diameter of the pendulum rollers, and the pendulum rollers can be inserted only after the pendulum mass carrier and pendulum masses have been separated.

[0019] According to an advantageous embodiment of the method, after the pendulum rollers have been placed on the raceways to form a pendulum bearing, side discs can be added to prevent the pendulum rollers from falling out. The side discs can be attached to the pendulum masses and thus also serve to increase their mass. Alternatively, the side discs can be arranged on the pendulum mass carrier. The side discs radially overlap at least a portion of the pendulum rollers.

[0020] The proposed centrifugal pendulum, produced by the proposed method, contains a pendulum mass carrier arranged to rotate about an axis of rotation and at least two, for example two to six, pendulum masses distributed around the circumference, which are mounted on the pendulum mass carrier by means of pendulum bearings in a pendulum plane perpendicular to the axis of rotation along a pendulum path so as to oscillate freely.

[0021] In an advantageous embodiment, each pendulum mass of the proposed centrifugal pendulum has two pendulum bearings spaced apart in the circumferential direction, so that the pendulums, in the centrifugal field of the pendulum mass carrier rotating about the axis of rotation, resemble a pendulum with a bifilar suspension with respect to their pendulum path. By appropriately designing the raceways, a pendulum motion of a pendulum with parallel or trapezoidally arranged pendulum strings, or a free-form pendulum motion, can be provided. Preferably, a predetermined breaking point can be arranged radially outwards between the pendulum masses and the pendulum mass carrier in the circumferential direction between the pendulum bearings.

[0022] The pendulum masses, which are received in the recesses by means of corresponding material cutouts, punchings and the like, or arranged axially spaced from the pendulum mass carrier, can have their final shape during tooling.

[0023] The invention is described in the following: Fig. The embodiments shown in 1 to 6 are explained in more detail. These show: Fig. 1 a partial view of a centrifugal pendulum, Fig. 2 the upper part of the centrifugal pendulum arranged around an axis of rotation of the Fig. 1 on average Fig. 3 A partial view of a raw part for the manufacture of the centrifugal pendulum of the Fig. 1 and Fig. 2, Fig. 4 a raw part with pendulum masses arranged around the circumference, Fig. 5 a raw part with opposing pendulum masses and Fig. 6 a raw part with pendulum masses arranged one above the other.

[0024] The Fig. Figure 1 shows a partial schematic view of the centrifugal pendulum 1. The centrifugal pendulum 1 comprises the pendulum mass carrier 2, which is rotatably arranged about an axis of rotation and is integrated, for example, into a dual-mass flywheel, a clutch disc, a hydrodynamic torque converter, or another device of a motor vehicle's drivetrain and rotatably arranged with the crankshaft of an internal combustion engine or a transmission input shaft of a gearbox. The pendulum mass carrier 2 contains pendulum masses 3, which are arranged around the circumference and are distributed as a second pendulum component 14, also made of sheet metal. These pendulum masses 3 are, for example, closed recesses 4 in which a pendulum mass 3 is arranged. The pendulum masses 3 are mounted so that they can oscillate relative to the pendulum mass carrier 2 by means of pendulum bearings 5 ​​spaced apart in the circumferential direction.The pendulum masses 3 oscillate in a plane perpendicular to the axis of rotation, so that when the pendulum mass carrier 2 rotates about the axis of rotation, the pendulum masses 3 are accelerated radially outwards and, depending on torsional vibrations, change their radial position along a predetermined pendulum path, thus damping the torsional vibrations. The pendulum path of the pendulum masses 3 is defined by the shape of the radially stacked raceways 6, 7 of the pendulum bearings 5. The pendulum roller 8 rolls on the raceways 6, 7.

[0025] To reduce the unit costs and tooling costs for the centrifugal pendulum 1, the pendulum mass carrier 2 and the pendulum masses 3 are manufactured as a single piece from a blank 9. For this purpose, only the remaining spaces 11 of the recesses 4 between the pendulum masses 3 and the pendulum mass carrier 2 are punched out using a stamping tool, and the pendulum mass carrier 2 and the pendulum masses 3 are each connected by means of the predetermined breaking point 10. Before or after the pendulum rollers 8 are joined, the predetermined breaking point 10, which is already separated in the operating state shown, is broken open.

[0026] The Fig. Figure 2 shows the upper part of the centrifugal pendulum 1 which is arranged to rotate about the axis of rotation d. Fig. Figure 1 shows a cross-sectional and schematic representation. The pendulum mass 3 is supported radially outwards in the recess 4 of the pendulum mass carrier 2 by means of the pendulum roller 8, subjected to centrifugal force. To prevent the pendulum roller 8 from falling out and to center the pendulum mass 3 relative to the pendulum mass carrier 2, side discs 12, made of thin sheet metal or plastic, are attached to both sides of the pendulum mass 3, for example by riveting. The in Fig. The side discs 12 (not shown) overlap the pendulum mass carrier 2 radially and, in addition to providing support and preventing loss, also serve to increase the mass of the pendulum masses 3. In further embodiments of the centrifugal pendulum 1, the side discs can be mounted on the pendulum mass carrier and overlap at least part of the pendulum rollers 8 radially.

[0027] The Fig. Figure 3 shows the raw part 9 in partial view before its assembly in the centrifugal pendulum 1 of the Fig. 1 and Fig. 2. After the stamping process, the pendulum components 13, 14 in the form of the pendulum masses 3 are connected in one piece to the pendulum mass carrier 2 by means of the predetermined breaking point 10. In the illustrated embodiment, the predetermined breaking point 10 is located, viewed in the circumferential direction, between the raceways 6, 7 of the pendulum bearings 5 ​​( Fig. 1) arranged. In further embodiments, one or more predetermined breaking points and / or one or more predetermined breaking points at other positions between the pendulum masses 3 and the pendulum mass carrier 2 may be provided. The raceways 6, 7 are preferably produced by die-cutting. In the area of ​​any die-cut opening in the raceways, a rolling action of the pendulum rollers 8 ( Fig. 1 and Fig. 2) can be avoided by having corresponding shoulders on the pendulum rollers 8 or by being designed asymmetrically in some other way. Axial support and thus axial positioning of the pendulum rollers 8 can be achieved by means of the side discs 12 ( Fig. 2) be provided for in an appropriate manner.

[0028] The Fig. Figures 4 to 6 each show in 3D view raw parts 9a, 9b, 9c, in which pendulum components 14a, 14b, 14c designed exclusively as pendulum masses 3a, 3b, 3c are connected to each other in one piece by means of the predetermined breaking points 10a, 10b, 10c.

[0029] The pendulum masses 3a, 3b, 3c are each connected at the predetermined breaking points 10a, 10b, 10c to support parts 15a, 15b, 15c, 15d and are separated at the predetermined breaking points 10a, 10b, 10c, for example, after hardening following stamping. Advantageously, all pendulum masses 3a, 3b, 3c of a centrifugal pendulum are accommodated on each of the blanks 9a, 9b, 9c. Alternatively, only a portion of the pendulum masses 3a, 3b, 3c or a larger number of pendulum masses 3a, 3b, 3c, for example for two centrifugal pendulums, can be accommodated on one blank 9a, 9b, 9c. The pendulum masses 3a, 3b, 3c are designed to act on the centrifugal pendulum 1 of the Fig. One alternative centrifugal pendulum is provided with pendulum masses 3a, 3b, 3c arranged between two axially spaced side parts forming the pendulum mass carrier or arranged on both sides of a pendulum flange. For this purpose, the recesses 16a, 16b, 16c with the raceways 7a, 7b, 7b are preferably formed by tooling. In the case of pendulum masses 3a, 3b, 3c provided for arrangement on both sides of a pendulum flange and connected to each other by means of spacer bolts – as shown in the illustrated embodiments – the openings 17a, 17b, 17c for the spacer bolts are also preferably punched out by tooling. Similarly, corresponding openings can be provided for multi-part layered and riveted pendulum mass parts, which can likewise be provided in one piece in a blank part according to blank parts 9a, 9b, 9c.

[0030] The Fig. Figure 4 shows an embodiment of a blank 9a with a support part 15a designed as a ring. Three pendulum masses 3a are arranged around the circumference of the support part 15a by means of two predetermined breaking points 10a spaced apart circumferentially. To improve the utilization of the radially inner installation space of the blank 9a, the pendulum masses can optionally be arranged circumferentially offset from one another on several diameters.

[0031] The Fig. Figure 5 shows an embodiment of a blank 9b in which two pendulum masses are connected opposite each other at the predetermined breaking points 10b by means of an internal support element 15b. To improve the utilization of the radially inner installation space of the blank 9a, Fig. 4 can, for example, be the raw part 9b of the Fig. 5 in the interior of the raw part 9a of the Fig. 4, wherein the radially opposite pendulum masses 3a, 3b are each connected to each other by means of predetermined breaking points in a way that allows them to be separated.

[0032] The Fig. Figure 6 shows an embodiment of a blank 9c in which several – here three – pendulum masses 3c are stacked on top of each other in a plane, maintaining a gap between them. The pendulum masses 3c are connected to the two support parts 15c, 15d by means of the predetermined breaking points 10c located at their respective circumferential ends. Reference symbol list 1 Centrifugal pendulum 2 pendulum mass carriers 3 Pendulum masses 3a Pendulum mass 3b Pendulum mass 3c Pendulum mass 4 Exclusion 5 pendulum bearings 6 Career 7 Career 7a Career 7b Career 7c track 8 Pendulum roller 9 Raw part 9a Raw part 9b Raw part 9c Raw part 10 Breakaway Point 10a Breakaway point 10b Breakaway point 10c Breakaway point 11 Free space 12 Side window 13 Pendulum component 14 Pendulum component 14a Pendulum component 14b Pendulum component 14c pendulum component 15a Carrier part 15b Carrier part 15c carrier part 15d carrier part 16a Exemption 16b Exclusion 16c Exclusion 17a Opening 17b Opening 17c opening d axis of rotation

Claims

[1] Method for manufacturing a centrifugal pendulum (1) with pendulum components (13, 14, 14a, 14b, 14c) made of sheet metal, namely a pendulum mass carrier (2) arranged about an axis of rotation (d) and pendulum masses (3, 3a, 3b, 3c) arranged on this in a way that allows it to oscillate, distributed over the circumference characterized by , that at least one stamped blank (9, 9a, 9b, 9c) is produced with at least two of the pendulum components (13, 14, 14a, 14b, 14c) and the pendulum components (13, 14, 14a, 14b, 14c) are subsequently separated, wherein the pendulum mass carrier (2) has recesses (4) in which the pendulum masses (3, 3a, 3b, 3c) are received, wherein at least one predetermined breaking point (10) is provided between each pendulum mass (3, 3a, 3b, 3c) and the pendulum mass carrier (2). [2] Method according to claim 1, characterized by, that the blank (9, 9a, 9b, 9c) is produced by means of a stamping process and that at least one predetermined breaking point (10, 10a, 10b, 10c) is provided between the pendulum components (13, 14, 14a, 14b, 14c). [3] Method according to claim 1 or 2, characterized by , that the raw part (9, 9a, 9b, 9c) is hardened as a whole and then separated into the raw components (13, 14, 14a, 14b, 14c). [4] Method according to any one of claims 1 to 3, characterized by , that during the assembly of the centrifugal pendulum (1) on raceways (6, 7) introduced during the manufacture of the blank (9, 9a, 9b, 9c) rolling pendulum rollers (8) are introduced between the pendulum masses (3, 3a, 3b, 3c) and the pendulum mass carrier (2) before, during or after a break of at least one predetermined breaking point (10). [5] Method according to claim 4, characterized by, that after the pendulum rollers (8) are placed on the raceways (6, 7) on the pendulum masses (3, 3a, 3b, 3c) or on the pendulum mass carrier (2) at least the pendulum rollers (8) are fitted with side discs (12) that at least partially overlap radially. [6] Method according to any one of claims 1 to 5, characterized by , that raceways (6, 7, 7a, 7b, 7c) provided on the pendulum components (13, 14, 14a, 14b, 14c) for the formation of pendulum bearings between the pendulum mass carrier (2) and the pendulum masses (3, 3a, 3b, 3c) are formed during the manufacture of the blank part (9, 9a, 9b, 9c) by tooling.

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