The invention relates to a drive lug for a torque converter and a torque converter cover with the drive lug attached. Specifically, the invention relates to configuring a drive lug to reduce stresses on the cover due to welding of the lug to the cover.
U.S. Pat. No. 6,926,131 discloses a lug welded to a radius, or curved surface, of a cover plate for a torque converter. The radius has residual stresses due to forming of the cover. Welding lugs in the cover radius creates heat affected zones, exacerbating the residual stresses in the cover. Unfortunately, when force is applied to the lugs, for example, during operation of the torque converter, the heat affected areas of the cover radius degrade rapidly.
Thus, there is a long-felt need for a means of reducing stresses associated with welding drive lugs to torque converter covers.
The present invention broadly comprises a drive lug for a torque converter cover, including: a central portion including first and second substantially opposite sides, first and second substantially opposite ends, a threaded opening for receiving a fastener, and a first width between the first and second sides; and first and second wing sections extending length-wise from the first and second ends, respectively. The first and second wing sections have second and third widths, respectively. Respective minimum extents of the second and third widths are less than a minimum extent of the first width. In one embodiment, respective maximum extents of the second and third widths are less than a maximum extent of the first width.
The present invention also broadly comprises drive lugs and cover for a torque converter, including a cover with a flat annular surface; a plurality of drive lugs; and respective welds connecting each lug in the plurality of lugs to the flat annular surface. Each drive lug from the plurality of drive lugs includes: a central portion including first and second substantially opposite sides, first and second substantially opposite ends, a threaded opening for receiving a fastener, and a first width between the first and second sides; and first and second wing sections extending length-wise from the first and second ends. At least first and second portions of the first and second wing sections, respectively, taper widthwise with respect to the first and second ends, respectively, the at least first and second portions have second and third widths, respectively, and respective minimum extents of the second and third widths are less than a minimum extent of the first width.
In one embodiment, respective maximum extents of the second and third widths are less than a maximum extent of the first width. In another embodiment, the flat annular surface has a radial width, the respective welds have respective maximum radial widths, and the respective maximum radial widths are no greater than the radial width of the flat annular surface.
The present invention further broadly comprises a method for assembling a torque converter cover.
It is a general object of the present invention to provide a drive lug to reduce stresses on a torque converter cover due to welding of the lug to the cover.
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.
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:
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.
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.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary 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.
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.
In another embodiment (not shown), wing sections 118 and 120 do not taper continuously toward ends 122 and 124. For example, respective widths of the wing sections may increase at some point moving along the wing sections in directions 130 and 132. Alternately stated, the wing sections “bulge” widthwise. In one embodiment, respective minimum extents of widths 122 and 124 are less than a minimum extent of width 114. In another embodiment, respective maximum extents of widths 122 and 124 are less than a maximum extent of width 114. Thus, at least some portion of the wing sections has a width less than the width of the center section.
In general, lug 100 is arranged to be welded to a cover (not shown) for a torque converter (not shown), as described infra. Portions of the wing sections are arranged to be welded to the cover, in particular, those portions of the wing sections having a width less than the width of the center portion.
The shape of lugs 100, noted supra, enables the minimization or elimination of contact between the welds and surfaces 204 and 206. For example, in one embodiment, the flat annular surface has radial width 210 and the respective welds have respective maximum radial widths 212 no greater than radial width 208. Thus, overlap between the lug and surfaces 204 and 206 is minimized or eliminated, which in turn minimizes or eliminates contact between the welds and surfaces 204 and 206. Lug 100 can be positioned on cover 200 to accommodate various orientations of bolts or fasteners for a flexplate (not shown) to which cover 200 is to be connected, while still minimizing or eliminating contact between the welds and surfaces 204 and 206. For example, it is common for a cover, in particular, lugs for the cover, to be adapted to the configuration of the flexplate. One aspect of the configuration of the flexplate fasteners is the radial position of the fasteners, which dictates the radial position of openings 112. That is, openings 112 must be radially positioned to axially align with/accept the fasteners. Advantageously, since widths 126 and/or 128 are less than width 114, the radial position of opening 112 can be adjusted while still minimizing or eliminating overlap of lugs 100 with surfaces 204 and 206. For example, as shown in
Advantageously, by limiting or eliminating the contact between the welds and surfaces 204 and 206, heating of surfaces 204 and 206 by application of the welds is minimized, and stresses associated with such heating also are minimized. Thus, the strength and durability of the cover are increased without the need to otherwise modify the cover, for example, by increasing thickness 220 of the cover.
The following should be viewed in light of
In one embodiment, the cover includes a first annular surface continuous with the flat annular surface, disposed radially inside the flat annular surface, and curved in an axial direction and a second annular surface continuous with the flat annular surface, disposed radially outside the flat annular surface, and curved in an axial direction. In another embodiment, the flat annular surface has a radial width and a fourth step restricts respective maximum radial widths for the welds to be no greater than the radial width. In a further embodiment, a fifth step restricts contact between welds and the cover to the flat annular region.
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.
This application claims the benefit under 35 U.S.C. §119(e) of U. S. Provisional Application No. 61/132,825 filed on Jun. 23, 2008, which application is incorporated herein by reference in its entirety.
Number | Date | Country | |
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61132825 | Jun 2008 | US |