WO2009143958A1

WO2009143958A1 - Centering feature of a flexplate to pilot the hub of a dry hybrid damper

Info

Publication number: WO2009143958A1
Application number: PCT/EP2009/003313
Authority: WO
Inventors: Michael Hodge; Thomas Heck
Original assignee: Luk Lamellen Und Kupplungsbau Beteiligungs Kg
Priority date: 2008-05-28
Filing date: 2009-05-11
Publication date: 2009-12-03
Also published as: CN102046997A; DE112009001221T5

Abstract

A flexplate for centering a diy hybrid damper, including a circumferential surface arranged to engage a circumferential surface for a hub for the damper to center the hub and the flexplate and a first portion arranged to at least indirectly engage a crankshaft to center the flexplate on the crankshaft. In one embodiment, the first portion includes at least one radially inwardly facing surface arranged to engage a radially outwardly facing surface on the crankshaft. In another embodiment, the flexplate includes a second portion arranged for connecton with at least one cover plate for the damper. In a further embodiment, the circumferential surface for the flexplate is radially inwardly facing and the circumferential surface for the hub is radially outwardly facing or the circumferential surface for the flexplate is radially outwardly facing and the circumferential surface for the hub is radially inwardly facing.

Description

CENTERING FEATURE OF A FLEXPLATE TO PILOT THE HUB OF

A DRY HYBRID DAMPER

FIELD OF THE INVENTION

[0001] The invention relates to means of centering the hub and flange assembly of a damper, in particular, a dry hybrid damper.

BACKGROUND OF THE INVENTION [0002] It is known to center a wet hybrid damper. Unfortunately, such techniques may not be applicable to a dry hybrid damper. [0003] Thus, there is a long-felt need for a means of centering a dry hybrid damper.

BRIEF SUMMARY OF THE INVENTION [0004] The present invention broadly comprises a flexplate for centering a dry hybrid damper, including a circumferential surface arranged to engage a circumferential surface for a hub for the damper to center the hub and the flexplate and a first portion arranged to at least indirectly engage a crankshaft to center the flexplate on the crankshaft. In one embodiment, the first portion includes at least one radially inwardly facing surface arranged to engage a radially outwardly facing surface on the crankshaft. In another embodiment, the flexplate includes a second portion arranged for connecton with at least one cover plate for the damper. In a further embodiment, the circumferential surface for the flexplate is radially inwardly facing and the circumferential surface for the hub is radially outwardly facing or the circumferential surface for the flexplate is radially outwardly facing and the circumferential surface for the hub is radially inwardly facing. [0005] In one embodiment, the portion arranged for connection to the crankshaft includes a plurality of features arranged to engage a plurality of protrusions on the crankshaft. In another embodiment, the plurality of features includes a plurality of holes. In a further embodiment, the flexplate includes a radial wall arranged to engage an axial end for the hub. In yet another embodiment, the radial wall and the circumferential surface for the flexplate are connected. In one embodiment, the hub is integral to the damper. In another embodiment, an outer surface of the hub and a flange for the damper are engaged. [0006] The present invention also broadly comprises a dry hybrid damper assembly, including: a flexplate with a radially inwardly facing circumferential surface, a first portion arranged for connection to a crankshaft, and a second portion; a hub with a radially outwardly facing circumferential surface engaged with the radially inwardly facing circumferential surface to center the hub and the flexplate; and a damper rotationally connected to the second portion of the flexplate and rotationally connected to the hub. In one embodiment, the damper includes at least one cover plate connected to the second portion of the flexplate and a flange connected to the hub. In another embodiment, the first portion of the flexplate includes a plurality of holes arranged to engage a plurality of protrusions on the crankshaft.

[0007] The present invention further broadly comprises a dry hybrid damper assembly, including a flexplate with a radially outwardly facing circumferential surface and a portion arranged for connection to a crankshaft and a one-piece flange/damper hub with a radially inwardly facing circumferential surface at least indirectly engaged with the radially outwardly facing circumferential surface to center the one-piece damper/flange hub and the flexplate.

[0008] As well, the present invention also broadly comprises a method for centering a dry hybrid damper assembly.

[0009] It is a general object of the present invention to provide a flexplate for centering a hub and flange assembly for a dry hybrid damper with the rest of the damper. It also is a general object of the present invention to provide a dry hybrid damper with a flexplate centering a hub and flange assembly for the damper

[0010] These and other objects and advantages of the present invention will be readily appreciable from the following description of preferred embodiments of the invention and from the accompanying drawings and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The nature and mode of operation of the present invention will now be more fully described in the following detailed description of the invention taken with the accompanying drawing figures, in which: Figure IA is a perspective view of a cylindrical coordinate system demonstrating spatial terminology used in the present application;

Figure IB is a perspective view of an object in the cylindrical coordinate system of Figure IA demonstrating spatial terminology used in the present application; Figure 2 is a front view of a present invention flexplate with a damper and a crankshaft;

Figure 3 a cross-sectional view of the flexplate, damper, and crankshaft shown in Figure 2, generally along line 3-3 in Figure 2;

Figure 4 a cross-sectional view of the flexplate, damper, and crankshaft shown in Figure 2, generally along line 4-4 in Figure 2;

Figure 5 is a perspective view of the flexplate shown in Figure 2;

Figure 6 a detail of area 6 shown in Figure 5; and,

Figure 7 a partial cross-sectional view of a present invention flexplate with a one-piece flange/damper hub. DETAILED DESCRIPTION OF THE INVENTION

[0012] At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical, or functionally similar, structural elements of the invention. While the present invention is described with respect to what is presently considered to be the preferred aspects, it is to be understood that the invention as claimed is not limited to the disclosed aspects.

[0013] Furthermore, it is understood that this invention is not limited to the particular methodology, materials and modifications described and as such may, of course, vary. It is also understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to limit the scope of the present invention, which is limited only by the appended claims.

[0014] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinaiy skill in the art to which this invention belongs. Although any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the invention, the preferred methods, devices, and materials are now described.

[0015] Figure IA is a perspective view of cylindrical coordinate system 80 demonstrating spatial terminology used in the present application. The present invention is at least partially described within the context of a cylindrical coordinate system. System 80 has a longitudinal axis 81, used as the reference for the directional and spatial terms that follow. The adjectives "axial," "radial," and "circumferential" are with respect to an orientation parallel to axis 81, radius 82 (which is orthogonal to axis 81), and circumference 83, respectively. The adjectives "axial," "radial" and "circumferential" also are regarding orientation parallel to respective planes. To clarify the disposition of the various planes, objects 84, 85, and 86 are used. Surface 87 of object 84 forms an axial plane. That is, axis 81 forms a line along the surface. Surface 88 of object 85 forms a radial plane. That is, radius 82 forms a line along the surface. Surface 89 of object 86 forms a circumferential plane. That is, circumference 83 forms a line along the surface. As a further example, axial movement or disposition is parallel to axis 81, radial movement or disposition is parallel to radius 82, and circumferential movement or disposition is parallel to circumference 83. Rotation is with respect to axis 81.

[0016J The adverbs "axially," "radially," and "circumferentially" are with respect to an orientation parallel to axis 81, radius 82, or circumference 83, respectively. The adverbs "axially," "radially," and "circumferentially" also are regarding orientation parallel to respective planes.

[0017] Figure IB is a perspective view of object 90 in cylindrical coordinate system 80 of

Figure IA demonstrating spatial terminology used in the present application. Cylindrical object 90 is representative of a cylindrical object in a cylindrical coordinate system and is not intended to limit the present invention in any manner. Object 90 includes axial surface 91, radial surface 92, and circumferential surface 93. Surface 91 is part of an axial plane, surface 92 is part of a radial plane, and surface 93 is part of a circumferential plane.

[0018] Figure 2 is a front view of present invention fl expiate 10 with a damper and a crankshaft. [0019] Figure 3 a cross-sectional view of flexplate 10, the damper, and the crankshaft shown in Figure 2, generally along line 3-3 in Figure 2.

[0020] Figure 4 a cross-sectional view of flexplate 10, the damper, and the crankshaft shown in Figure 2, generally along line 4-4 in Figure 2. [0021] Figure 5 is a perspective view of flexplate 10 shown in Figure 2.

[0022] Figure 6 a detail of area 6 shown in Figure 5. The following should be viewed in light of Figures 2 through 6. The flexplate includes circumferential surface 12 arranged to at least indirectly engage circumferential surface 14 for hub 16 of damper 18 assembly to center the hub and the flexplate. As shown in the figures the circumferential surfaces are in direct contact. In one embodiment (not shown), an intermediate device, such as a bushing, is placed in contact between the circumferential surfaces, thus, the surfaces are indirectly engaged. The flexplate also includes portion 20 arranged to engage a crankshaft, for example, crankshaft 22, and center the flexplate on the crankshaft. In one embodiment, the flexplate includes portion 24, for example, an outer circumferential portion of the flexplate, arranged for connection with at least one cover plate, for example, cover plates 26 and 28, for the damper. Circumferential surface 12 is radially inwardly facing and circumferential surface 14 is radially outwardly facing. [0023] In one embodiment, the portion of the flexplate arranged for connection to the crankshaft includes a plurality of features 30 arranged to engage a plurality of protrusions 32 on the crankshaft. In another embodiment, the features 30 are holes, or piercings, in the flexplate. In a further embodiment, the flexplate includes radial wall 34 arranged to engage axial end 36 for the hub. Wall 34 and surface 12 are connected, so that the flexplate cups end 36. [0024] The following provides further detail regarding flexplate 1. In one embodiment, portion 20 is pierced to form surfaces 38, which engage surface 40 on the crankshaft. In another embodiment, surface 40 is a machined step in the crankshaft. In a further embodiment, forming 42 of the flexplate includes surface 12 and wall 36 and the hub is inserted in the forming. The flexplate is rigidly connected to, for example, rotationally connected to, and centered to damper 18, for example, cover plates 26 and 28, using any means known in the art, for example, dowel pins or rivets 44. By rotationally connected, or secured, we mean that the flexplate and the damper are connected such that the two components rotate together, that is, the two components are fixed with respect to rotation. Rotationally connecting two components does not necessarily limit relative movement in other directions. For example, it is possible for two components that are rotationally connected to have axial movement with respect to each other via a spline connection. However, it should be understood that rotational connection does not imply that movement in other directions is necessarily present. For example, two components that are rotationally connected can be axially fixed one to the other. The preceding explanation of rotational connection is applicable to the discussions infi'ct.

[0025] Since flexplate 10 is centered to the main part of damper 18, and hub 16 is centered into flexplate 10, the hub and flange 46 assembly of the damper are centered and protected against misalignment with respect to the rest of the damper. In one embodiment, the flexplate is formed by stamping. Advantageously, a stamped flexplate does not require a secondary machining process because all required tolerances are achievable in the stamping process. [0026] In one embodiment, outer surface 48 of the hub and flange 46 for the damper, for example, distal end 49, are engaged. Torque is transmitted from the flange to the hub when the damper is in operation, that is, when a load is applied to the flexplate. In another embodiment, rivets 44 connect the flexplate to inertia rings 50 and 51. In another embodiment, ring gear 52 is attached to the flexplate by any means known in the art, for example, by welding, and is engageable with a starter gear (not shown) to start a vehicle (not shown) in which the flexplate is installed. In general, flexplate 10 centers the hub and flange assembly to the rest of the damper assembly and to the crankshaft.

[0027] Figure 7 a partial cross-sectional view of present invention flexplate 56 with one- piece flange/damper hub 58. That is, hub portion 60 and flange 62 for damper 64 (only partially shown) are integral to the hub. The flexplate includes circumferential surface 66 arranged to directly or indirectly engage circumferential surface 68 for hub 58 to center the hub and the flexplate. In one embodiment, a friction-reducing device, for example, bushing 70 is disposed between the flexplate and element 58. In another embodiment (not shown) surfaces 66 and 68 are in direct contact. [0028] The flexplate also includes portion 72 arranged to engage a crankshaft, for example, crankshaft 74, and center the flexplate on the crankshaft. In one embodiment, portion 72 is bolted to the crankshaft. In one embodiment, surface 68 is facing radially outward and surface 70 is facing radially inward. [0029] Thus, single piece flexplate 56 is for centering both the primary and secondary sides of a damper (only parts of which are shown), for example, damper 64 through inside surface 68 of one-piece damper flange/damper hub 58. In one embodiment, external splines 76 on flange/hub 58 are formed by an extension process in press or can be rolled as a secondary operation. Radius 78 of surface 68 is a centering diameter and is formed to finished size and dimension during an extension process.

[0030] The following should be viewed in light of Figures 2 through 7. The following describes a present invention method for centering a dry hybrid damper assembly. Although the method is presented as a sequence of steps for clarity, no order should be inferred from the sequence unless explicitly stated. A first step rotationally connects and centers a flexplate with a crankshaft and a second step controls a radial position of a circumferential surface of a hub for the damper using a circumferential surface of the flexplate to center the hub and the flexplate. In one embodiment, a third step rotationally connects the flexplate with at least one cover plate for the damper. In another embodiment, the circumferential surfaces for the flexplate and the hub are radially inwardly facing and radially outwardly facing, respectively, or the ckcumferential surfaces for the flexplate and the hub are radially outwardly facing and radially inwardly facing, respectively.

[0031] hi one embodiment, rotationally connecting and centering a flexplate with a crankshaft includes engaging a plurality of holes on the flexplate with a plurality of protrusions on the crankshaft. In another embodiment, a fourth step engages an outer surface of the hub and a flange for the damper, hi a further embodiment, the hub is integral to the damper.

[0032] Thus, it is seen that the objects of the present invention are efficiently obtained, although modifications and changes to the invention should be readily apparent to those having ordinary skill in the art, which modifications are intended to be within the spirit and scope of the invention as claimed. It also is understood that the foregoing description is illustrative of the present invention and should not be considered as limiting. Therefore, other embodiments of the present invention are possible without departing from the spirit and scope of the present invention.

Claims

CLAIMSWhat We Claim Is:

1. A flexplate for centering a dry hybrid damper, comprising: a circumferential surface arranged to at least indirectly engage a circumferential surface for a hub for the damper to center the hub and the flexplate; and a first portion arranged to engage a crankshaft to center the flexplate on the crankshaft.

2. The flexplate of Claim 1 wherein the first portion includes at least one radially inwardly facing surface arranged to engage a radially outwardly facing surface on the crankshaft.

3. The flexplate of Claim 1 further comprising a second portion arranged for connecton with at least one cover plate for the damper.

4. The flexplate of Claim 1 wherein the circumferential surface for the flexplate is radially inwardly facing and the circumferential surface for the hub is radially outwardly facing.

5. The flexplate of Claim 1 wherein the portion arranged for connection to the crankshaft includes a plurality of features arranged to engage a plurality of protrusions on the crankshaft.

6. The flexplate of Claim 4 wherein the plurality of features includes a plurality of holes.

7. The flexplate of Claim 1 further comprising a radial wall arranged to engage an axial end for the hub.

8. The flexplate of Claim 6 wherein the radial wall and the circumferential surface for the flexplate are connected.

9. The flexplate of Claim 1 wherein the circumferential surface for the flexplate is radially outwardly facing and the circumferential surface for the hub is radially inwardly facing.

10. The flexplate of Claim 1 wherein the hub is integral to the damper.

11. The flexplate of Claim 1 wherein an outer surface of the hub and a flange for the damper are engaged.

12. A dry hybrid damper assembly, comprising: a flexplate with a radially inwardly facing circumferential surface, a first portion arranged for connection to a crankshaft, and a second portion; a hub with a radially outwardly facing circumferential surface engaged with the radially inwardly facing circumferential surface to center the hub and the flexplate; and, a damper rotationally connected to the second portion of the flexplate and rotationally connected to the hub.

13. The damper assembly of Claim 11 wherein the damper includes at least one cover plate connected to the second portion of the flexplate and a flange connected to the hub.

14. The damper assembly of Claim 11 wherein the first portion of the flexplate includes a plurality of holes arranged to engage a plurality of protrusions on the crankshaft.

15. A diy hybrid damper assembly, comprising: a flexplate with a radially outwardly facing circumferential surface and a portion arranged for connection to a crankshaft; and, a one-piece flange/damper hub with a radially inwardly facing circumferential surface at least indirectly engaged with the radially outwardly facing circumferential surface to center the one-piece damper/flange hub and the flexplate.

16. A method for centering a dry hybrid damper assembly, comprising: rotationally connecting and centering a flexplate with a crankshaft; and, controlling a radial position of a circumferential surface of a hub for the damper using a circumferential surface of the flexplate to center the hub and the flexplate.

17. The method of Claim 15 including rotationally connecting the flexplate with at least one cover plate for the damper.

18. The method of Claim 15 wherein the circumferential surfaces for the flexplate and the hub are radially inwardly facing and radially outwardly facing, respectively, or wherein the circumferential surfaces for the flexplate and the hub are radially outwardly facing and radially inwardly facing, respectively.

19. The method of Claim 15 wherein rotationally connecting and centering a flexplate with a crankshaft includes engaging a plurality of holes on the flexplate with a plurality of protrusions on the crankshaft.

20. The method of Claim 15 wherein the hub is integral to the damper.

21. The method of Claim 15 further comprising engaging an outer surface of the hub and a flange for the damper.