BRIEF DESCRIPTION OF THE DRAWINGS
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:
FIG. 1 is a perspective view of a torque converter impeller having a housing shell and a plurality of impeller blades installed therein;
FIG. 2 is a cross-sectional view of the torque converter impeller housing shell of FIG. 1 having the blades removed and a plurality of slots arranged about a first circumferential surface of the shell;
FIG. 3 is an enlarged cross-sectional view of the housing shell and slot shown in the encircled region 3 of FIG. 2 showing a present invention impeller blade disposed therein;
FIG. 4 is an enlarged cross-sectional view of the housing shell and slot shown in the encircled region 4 of FIG. 2 showing a present invention impeller blade disposed therein;
FIG. 5 is a cut-away perspective view of an impeller housing shell having a present invention impeller blade being installed therein;
FIG. 6
a is a perspective view of an embodiment of a present invention torque converter impeller blade prior to bending a tab;
FIG. 6
b is a cut-away perspective view of the encircled region of FIG. 6a;
FIG. 7
a is a perspective view of the embodiment of the torque converter impeller blade shown in FIG. 6a subsequent to bending the tab;
FIG. 7
b is a cut-away perspective view of the encircled region of FIG. 7a;
FIG. 8 is a side elevational view of a present invention torque converter impeller blade;
FIG. 9 is a back elevational view of the torque converter impeller blade shown in FIG. 8;
FIG. 10 is a partial cross-sectional view of a torque converter impeller housing shell including a present invention torque converter impeller blade having integral extended portions substantially tangential to the outer edge;
FIG. 11 is an enlarged cross-sectional view of the encircled region 11 of FIG. 10;
FIG. 12 is a partial cross-sectional view of a torque converter impeller housing shell including a present invention torque converter impeller blade having integral extended portions substantially tangential to the outer surface;
FIG. 13 is an enlarged cross-sectional view of the encircled region 13 of FIG. 12;
FIG. 14A is a perspective view of a cylindrical coordinate system demonstrating spatial terminology used in the present application; and,
FIG. 14B is a perspective view of an object in the cylindrical coordinate system of FIG. 14A demonstrating spatial terminology used in the present application.
DETAILED DESCRIPTION OF THE INVENTION
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 embodiment, it is to be understood that the invention as claimed is not limited to the preferred embodiment.
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 embodiments only, and is not intended to limit the scope of the present invention.
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.
Adverting now to the figures, FIG. 14A is a perspective view of cylindrical coordinate system 200 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 200 has a longitudinal axis 201, 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 201, radius 202 (which is orthogonal to axis 201), and circumference 203, respectively. The adjectives “axial,” “radial” and “circumferential” also are regarding orientation parallel to respective planes. To clarify the disposition of the various planes, objects 204, 205, and 206 are used. Surface 207 of object 204 forms an axial plane. That is, axis 201 forms a line along the surface. Surface 208 of object 205 forms a radial plane. That is, radius 202 forms a line along the surface. Surface 209 of object 206 forms a circumferential plane. That is, circumference 203 forms a line along the surface. As a further example, axial movement or disposition is parallel to axis 201, radial movement or disposition is parallel to radius 202, and circumferential movement or disposition is parallel to circumference 203. Rotation is with respect to axis 201.
The adverbs “axially,” “radially,” and “circumferentially” are with respect to an orientation parallel to axis 201, radius 202, or circumference 203, respectively. The adverbs “axially,” “radially,” and “circumferentially” also are regarding orientation parallel to respective planes.
FIG. 14B is a perspective view of object 210 in cylindrical coordinate system 200 of FIG. 14A demonstrating spatial terminology used in the present application. Cylindrical object 210 is representative of a cylindrical object in a cylindrical coordinate system and is not intended to limit the present invention is any manner. Object 210 includes axial surface 211, radial surface 212, and circumferential surface 213. Surface 211 is part of an axial plane, surface 212 is part of a radial plane, and surface 213 is part of a circumferential plane.
FIG. 1 shows a perspective view of torque converter impeller 20 including housing shell 22 having a plurality of slots 24 with impeller blades 26 installed therein. A more detailed description of the structure of blades 26, slots 24 and the interaction therebetween is discussed infra. As one of ordinary skill in the art recognizes, a torque converter impeller is structurally similar to a torque converter turbine. Thus, although the embodiments discussed infra are directed at an impeller, similar structures may also be used to construct a turbine, and such embodiments are within the spirit and scope of the claims.
Each blade 26 includes tab 28. The plurality of tabs 28 are disposed within respective slots 30 of core ring 32. Subsequently, the assembly is placed through a rolling process, bending the plurality of tabs 28, as shown in FIG. 1, thereby retaining the plurality of blades 26 within core ring 32. Then impeller 20 is washed to remove any dirt, oil, debris, etc. which may have collected in or on impeller 20 during processing. Following the cleaning and drying operations, blades 26 are brazed to inner surface 34 of housing shell 22 along edges 36 of blades 26, i.e., the mating edge between blades 26 and housing shell 22. One of ordinary skill in the art will recognize that methods other than brazing may be used to fixedly secure blades 26 to housing shell 22, for example, laser welding, and such methods are within the spirit and scope of the claimed invention. After completing the brazing operation, a complete torque converter may then be constructed, however that portion of assembly is not particularly germane to the present invention and therefore is not discussed. In a preferred embodiment, blades 26 are brazed to housing shell 22, however, for low torque applications, blades 26 may merely be compressively engaged within slots 24 as described infra.
The following discussion is best understood in view of FIGS. 2 through 9. FIG. 2 shows a cross-sectional view of torque converter impeller 20 having a plurality of slots 24 arranged about a first circumferential surface of impeller housing shell 22, while FIGS. 3 and 4 are enlarged cross-sectional views of the encircled regions 3 and 4, respectively, of FIG. 2 showing a slot having a bent tab of impeller blade 26 disposed therein. FIG. 5 depicts a cut-away perspective view of impeller housing shell 22 with impeller blade 26 being installed therein. FIG. 6a is a perspective view of an embodiment of impeller blade 26 prior to bending tab 38, while FIG. 6b shows a cut-away perspective view of the encircled region of FIG. 6a. FIG. 7a is a perspective view of impeller blade 26 shown in FIG. 6a subsequent to bending tab 38, i.e., forming rotated tab 40, while FIG. 7b shows a cut-away perspective view of the encircled region of FIG. 7a. Lastly, FIG. 8 is a side elevational view of a second embodiment of impeller blade 26 including extended tab 42, while FIG. 9 is a back elevational view of the embodiment of impeller blade 26 shown in FIG. 8.
Slots 24 are disposed about a circumference defined by diameter 44, slots 46 are disposed about a circumference defined by diameter 48, while slots 50 are disposed about a circumference defined by diameter 52. The positions of slots 24, 46 and 50 are critical, as the efficiency of impeller 20 is dependant on the regular placement of blades 26 about inner surface 34 of housing shell 22. As described supra, the prior art teaches forming slots by means of coining slots perpendicular to the metal surface thereby leaving a portion of material at the entrance of the slot which can retain an inserted impeller blade. Contrarily, slots 24, 46 and 50 are formed by coining operations performed parallel to axis of rotation 54 of housing shell 22. Other means of forming slots within housing shell 22 are also possible, e.g., laser or mechanical cutting, and one of ordinary skill in the arts will recognize that such means are within the spirit and scope of the claimed invention.
In the embodiments shown in FIGS. 3 through 5, blade 26 is installed in housing shell 22 by compressively engaging tab 40 within first slot 24 and then inserting tab 56 within slot 46 and tab 58 within slot 50, thereby retaining blade 26 within shell 22. By compressively engaging we mean that a tab and one or more walls of a slot are touching and normal forces are present between the tab and walls. That is, the tabs are forced into the slots so that the tabs at least partially distort and push against the walls. The normal force in a compressive engagement is stronger than the force associated with a slip or friction fit, also referred to as retaining, in which little or no distortion of the tab occurs. The compressive engagement of tab 40 in the slot prevents the axial movement of the blade away from inner surface 34.
In FIG. 3, the tab engaged in slot 24 is rotated tab 40, which is similar to tab 38, and is formed by rotating tab 38 about axis 59, which extends from outside edge 36. In some aspects, axis 59 is substantially aligned with an axis extending from outside edge 36. For example, FIG. 6b shows tab 38 before the rotation and FIG. 7b shows tab 40 (tab 38 after being rotated about axis 59). In some aspects, slot 24 includes axial walls 60 and 62. As rotated tab 40 is inserted within slot 24, corners 64 and 66 compressively engages walls 60 and 62, thereby retaining blade 26 within shell 22. Corners 64 and 66 exert pressure on the walls in a substantially circumferential direction with respect to a torque converter in which the blade is to be installed, thereby retaining blade 26 within shell 22.
FIG. 4 shows tab 42 and chamfered slot 68. As shown in FIGS. 8 and 9, extended tab 42 is connected to blade 26 via joint 70 and includes flange 72, leaving a gap between flange 72 and edge 36. Additionally, in some aspects, flange 72 is rotated about an axis (not shown) extending from edge 36 through joint 70, similar to the formation of rotated tab 40. In some aspects, this axis is similar in orientation to axis 59. Chamfered slot 68 includes walls 74 and 76 and chamfer wall 78. Chamfer wall 78 provides means to guide extended tab 42 as it is inserted within slot 68. As tab 42 is inserted, corner 80 contacts chamfer wall 78 which further rotates extended tab 42 about the axis of joint 70. Once tab 42 is fully inserted, corners 80 and 82, of tab 42, compressively engage walls 74 and 76, respectively, thereby retaining blade 26 within shell 22.
Present invention rotated tabs also can be viewed in terms of respective planes. For example, referring to FIGS. 6a through 7b, blade 26 includes body 86 with surface 88. In general, tabs extend from body 86. Tab 40 includes surface 90. As shown in FIG. 7b, surfaces 88 and 90 are misaligned. As described supra, blades 26 are retained within housing shell 22 via compressive engagement between a tab integral to blade 26 and the inner walls of a slot, e.g., slot 24 having walls 60 and 62. Thus, the tab inserted within slot 24 should be rotated sufficiently so that one or more corners compressively engage the inner walls. In other words, the width from corner to corner of the rotated tab should be wider than the width of the slot. However, other methods (not shown) of forming a tab and/or a slot are also possible. For example, tab 42 may include material extending in two directions from joint 70, thereby forming a ‘T’, tab 38 may be bent instead of rotated, or slot 68 may include an additional chamfered wall as a part of wall 76. Such variations typically require that the modified tabs are able to generate compressive engagements such that the axial movement of a blade with the modified tabs is prevented once the modified tabs and any remaining tabs are inserted in respective slots in a toque converter shell. One of ordinary skill in the art will recognize that such variations are within the spirit and scope of the claimed invention.
FIG. 10 shows a cross-sectional view of torque converter impeller housing shell 122 having slots 124 and torque converter impeller blade 126 having integral extended portions substantially tangential to edge 136.
FIG. 11 is an enlarged cross-sectional view of the encircled region 11 of FIG. 10 showing housing shell 122 and slot 146. The following should be viewed in light of FIGS. 10 and 11. In some aspects, blade 126 includes tab 128 arranged to engage a core ring (not shown). In some aspects, blade 126 includes extended tab 152 arranged to engage slot 146. Similar to the embodiments described supra, tab 138 is first inserted within slot 124, and subsequently extended tab 152 and then tab 154 are pushed toward and inserted within slots 146 and 150, respectively. As extended tab 152 is inserted within slot 146, shoulder 156 compressively engages wall 158, while corner 160 compressively engages wall 162, thereby retaining blade 126 within housing shell 122. That is, length 164 of tab 152 is greater than width 166 of slot 146, such that tab 152 cannot fit in the slot without distorting to produce the compressive engagement.
FIG. 12 shows a cross-sectional view of a second configuration of torque converter impeller housing shell 170 having slots 124 and torque converter impeller blade 126 having integral extended portions substantially tangential to edge 136.
FIG. 13 is an enlarged cross-sectional view of the encircled region 13 of FIG. 12 showing housing shell 170 and slot 172. The following should be viewed in light of FIGS. 12 and 13. Similar to the embodiments described supra, tab 138 is first inserted within slot 124 and then tabs 152 and 174 are pushed toward and inserted within slots 146 and 172, respectively. As extended tab 174 is inserted within slot 172, corner 176 is deflected by chamfer 178 and then compressively engages wall 180. That is, the spacing between tabs 138, 152, and 174 and the spacing of slots 124, 146, and 172 is such that end 182 extends beyond wall 180 when tabs 152 are engaged in slots 146, causing a compressive fit between end 182 and wall 180. That is, tab 174 must be compressed to fit in slot 172.
The following should be viewed in light of FIGS. 10 through 13. Blade 126 may be compressively engaged, and thereby retained, within housing shells 122 or 170 using tab 152, tab 174, or both tabs 152 and 174.
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.
Patent Application
20070258820
