Torque transmitting assembly including a sprocket assembly displaceable along a shaft and method thereof

This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 62/033,406, filed Aug. 5, 2014, which application is incorporated herein by reference in its entirety.

The present disclosure relates to a torque assembly including a shaft and a sprocket assembly displaceable along the shaft. In particular, the sprocket assembly is axially displaceable along the shaft to assume a position in which the sprocket assembly is non-rotatably connected to the shaft, and the sprocket assembly is axially displaceable along the shaft to transition out of the non-rotatably connected position, for example, to remove the sprocket assembly from the shaft. In an example embodiment, the shaft is an input shaft for a transmission.

In known torque converter and transmission configurations, portions of the input shaft that could be used for providing torque to components outside of the torque converter and transmission are inaccessible and/or torque transmitting components, such as a sprocket, cannot be mounted to the shaft. For example, the sprocket would need to be rotationally fixed to the shaft during assembly. Radially extending keys on the shaft mated to grooves in the sprocket could be used to fix the sprocket; however, the keys would interfere with bushings that must be installed on the shaft to engage the torque converter housing and stator shaft support. Grooves in the shaft mated with keys extending from the sprocket could be used; however the grooves would provide leak paths past the bushings. The sprocket cannot be welded to the shaft, since the sprocket must be removable to enable disassembly and repair of the transmission.

According to aspects illustrated herein, there is provided a torque transmitting assembly, including: a shaft including a longitudinal axis, first and second longitudinal ends through which the longitudinal axis passes, a radially outermost surface, a first portion including at least one indentation, and second and third portions between the first portion and the first and second longitudinal ends, respectively; and a sprocket assembly disposed about the shaft and including a sprocket with a plurality of circumferentially disposed and radially outwardly extending teeth and at least one key engaged with the sprocket. The sprocket assembly is displaceable along the shaft to displace the at least one key into the at least one indentation. The sprocket is non-rotatably connected the shaft when the at least one key is disposed in the at least one indentation. At least respective portions of the radially outermost surface are at a uniform distance from the longitudinal axis in a first radial direction orthogonal to the longitudinal axis and extending from the longitudinal axis.

According to aspects illustrated herein, there is provided a torque transmitting assembly, including: an input shaft for a transmission, the input shaft including a first portion with at least one indentation and, second and third portions between the first portion and first and second longitudinal ends of the shaft, respectively; and a sprocket assembly radially disposed about the shaft and including a sprocket with a plurality of circumferentially disposed radially outwardly extending teeth and at least one key. The at least one indentation terminates at respective boundaries between the first portion and the second portion and between the first portion and the third portion. The sprocket assembly is displaceable along the shaft: in a first axial direction from the second portion to the first portion to displace the at least one key into the at least one indentation; and in the first axial direction or in a second axial direction, opposite the first axial direction, from the first portion, with the at least one key displaced into the at least one indentation, to the third portion or second portion, respectively. When the sprocket assembly is radially disposed about the first portion: the at least one key is engaged with the at least one first indentation to non-rotatably connect the sprocket and the shaft; or the sprocket assembly is rotatable about the shaft to engage the at least one key with the at least one first indentation to non-rotatably connect the sprocket and the shaft.

According to aspects illustrated herein, there is provided a torque transmitting assembly, including a shaft and a sprocket. The shaft includes: a longitudinal axis; first and second longitudinal ends through which the longitudinal axis passes; a first portion including at least one indentation; and second and third portions between the first portion and the first and second longitudinal ends, respectively. The sprocket includes a plurality of circumferentially disposed and radially outwardly extending teeth. The sprocket is displaceable along the shaft to engage the at least one indentation to non-rotatably connect the sprocket and the shaft. The sprocket is rotatable for 360 degrees about the second and third portions.

Various embodiments are disclosed, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, in which:

FIG. 1 is a perspective view of a cylindrical coordinate system demonstrating spatial terminology used in the present application;

FIG. 2 is a side view of a torque transmitting assembly with a shaft and displaceable sprocket assembly;

FIG. 3 is an exploded view of the torque transmitting assembly of FIG. 2 ;

FIG. 4 is a cross-sectional view generally along line 4 - 4 in FIG. 2 ;

FIG. 5 is a cross-sectional view generally along line 5 - 5 in FIG. 2 ;

FIG. 6 is a perspective view of the sprocket assembly of FIG. 2 with cover plates removed;

FIG. 7 is a cross-sectional view generally along line 7 - 7 in FIG. 6 ;

FIG. 8 illustrates a torque transmitting assembly in a torque converter/transmission configuration; and,

FIG. 9 is a block diagram of a torque transmitting assembly in a torque converter/transmission configuration.

At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical, or functionally similar, structural elements of the disclosure. It is to be understood that the disclosure as claimed is not limited to the disclosed aspects.

Furthermore, it is understood that this disclosure 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 disclosure.

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 disclosure belongs. It should be understood that any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the disclosure.

FIG. 1 is a perspective view of a cylindrical coordinate system demonstrating spatial terminology used in the present application. The present application is at least partially described within the context of a cylindrical coordinate system. System 10 includes longitudinal axis 11 , used as the reference for the directional and spatial terms that follow. Axial direction AD is parallel to axis 11 . Radial direction RD is orthogonal to axis 11 . Circumferential direction CD is defined by an endpoint of radius R (orthogonal to axis 11 ) rotated about axis 11 .

To clarify the spatial terminology, objects 12 , 13 , and 14 are used. An axial surface, such as surface 15 of object 12 , is formed by a plane parallel to axis 11 . Axis 11 is coplanar with planar surface 15 ; however it is not necessary for an axial surface to be coplanar with axis 11 . A radial surface, such as surface 16 of object 13 , is formed by a plane orthogonal to axis 11 and coplanar with a radius, for example, radius 17 . Surface 18 of object 14 forms a circumferential, or cylindrical, surface. For example, circumference 19 forms a circle on surface 18 . As a further example, axial movement is parallel to axis 11 , radial movement is orthogonal to axis 11 , and circumferential movement is parallel to circumference 19 . Rotational movement is with respect to axis 11 . The adverbs “axially,” “radially,” and “circumferentially” refer to orientations parallel to axis 11 , radius 17 , and circumference 19 , respectively.

FIG. 2 is a side view of torque transmitting assembly 100 with shaft 102 and displaceable sprocket assembly 104 .

FIG. 3 is an exploded view of torque transmitting assembly 100 of FIG. 2 . The following should be viewed in light of FIGS. 2 and 3 . Torque transmitting assembly 100 includes shaft 102 and sprocket assembly 104 . Shaft 102 includes longitudinal axis LA, longitudinal ends 106 and 108 through which longitudinal axis AR passes, and portions 102 A, 102 B, and 102 C. Portion 102 A includes at least one indentation 110 . Portions 102 B and 102 C are located between portion 102 A and ends 106 and 108 , respectively. Sprocket assembly 104 is disposed about shaft 102 and includes sprocket 112 , at least one key 114 , and at least one resilient element 116 . Sprocket 112 includes at least one slot 118 and circumferentially disposed and radially outwardly extending teeth 120 .

FIG. 4 is a cross-sectional view generally along line 4 - 4 in FIG. 2 .

FIG. 5 is a cross-sectional view generally along line 5 - 5 in FIG. 2 ;

FIG. 6 is a perspective view of the sprocket assembly of FIG. 2 .

FIG. 7 is a cross-sectional view generally along line 7 - 7 in FIG. 6 . The following should be viewed in light of FIGS. 2 through 7 . In an example embodiment, shaft 102 includes indentations 110 A and 110 B. In an example embodiment, assembly 104 includes keys 114 A and 114 B and resilient elements 116 A and 116 B at least partly disposed in slots 118 A and 118 B, respectively. In an example embodiment, indentations 110 A and 110 B, keys 114 A and 114 B, resilient elements 116 A and 116 B, and slots 118 A and 118 B are each 180 degrees separate from each other. To simplify presentation, the discussion that follows is directed to indentation 110 A, keys 114 A, resilient element 116 A, and slot 118 A, with the understanding that unless stated otherwise, the discussion is applicable to any other groupings of indentations, keys, resilient elements, and slots, such as indentation 110 B, key 114 B, resilient element 116 B, and slot 118 B. Resilient elements 116 can be any resilient elements known in the art, including, but not limited to coil springs and leaf springs.

Resilient element 116 A is arranged to urge key 114 A in radial direction RD 1 , orthogonal to axis LA and toward axis LA. Sprocket 112 is non-rotatably connected to shaft 102 when key 114 A is at least partly disposed in indentation 110 A. Sprocket assembly 104 is displaceable along shaft 102 in opposite axial directions AD 2 and AD 1 , parallel to axis LA, from portion 102 A, with key 114 A disposed in indentation 110 A, to longitudinal ends 106 and 108 , respectively. Sprocket assembly 104 is displaceable along shaft 102 in directions AD 1 and AD 2 from portions 102 B and 102 C to portion 102 A, respectively, to displace key 114 A into indentation 110 A. Diameter D 1 of sprocket 112 is slightly larger than diameter D 2 of shaft 102 such that sprocket 112 fits snugly about the shaft but is axially displaceable along the shaft.

When assembly 104 is located about portion 102 A, sprocket 112 is rotatable with respect to segments 124 of shaft 102 circumferentially disposed between indentations 110 , for example, between indentations 110 A and 110 B. Sprocket 112 is rotatable for 360 degrees with respect to shaft 102 when assembly 104 is disposed about portions 102 B and 102 C. Indentation 110 A terminates at boundaries 126 A and 126 B between portion 102 A and portions 102 B and 102 C, respectively.

Key 114 A is arranged to displace, with respect to sprocket 112 , in radial direction RD 1 into indentation 110 A as assembly 104 displaces from portion 102 B or portion 102 C into indentation 110 A. Key 114 A is arranged to displace, in response to contact with radially outermost surface 128 of shaft 102 , in radial direction RD 2 , opposite radial direction RD 1 , as assembly 104 displaces from indentation 110 A to portion 102 B or portion 102 C. As assembly 104 displaces from indentation 110 A to portion 102 B or portion 102 C, key 114 A is arranged to compress resilient element 116 A. As assembly 104 displaces from portion 102 B or portion 102 C to indentation 110 A, resilient element 116 A is arranged to displace key 114 A in direction RD 1 . At least respective segments of surface 128 in portions 102 B and 102 C are at a uniform distance in direction RD 2 from axis LA, for example, one half of diameter D 2 . That is, there are no keys or protrusions extending from surface 128 and there are no grooves in surface 128 .

Indentation 110 A includes side walls 130 and 132 and end walls 134 and 136 connecting side walls 130 and 132 and positioned so that line L parallel to longitudinal axis LA passes through end walls 134 and 136 . End walls 134 and 136 slope from portions 102 B and 102 C, respectively, toward axis LA in radial direction RD 1 . As sprocket assembly 104 , in particular key 114 A, displaces between indentation 110 A and portion 102 B or portion 102 C, key 114 A is arranged to slide up end wall 134 or 136 , respectively.

Key 114 A includes side walls 138 and 140 arranged to engage side walls 130 and 132 , respectively, when key 114 A is disposed in indentation 110 A. Slot 118 A includes side walls 142 and 144 . Walls 142 and 144 are engaged with side walls 138 and 140 , respectively. Torque path T 1 is created from shaft 102 to sprocket 112 via side walls 130 , 138 , 140 , and 144 for torque applied to shaft 102 in rotational direction RTD 1 . Torque path T 2 is created from shaft 102 to sprocket 112 via side walls 132 , 140 , 138 , and 144 for torque applied to shaft 102 in rotational direction RTD 1 . For torque applied to sprocket 112 , paths T 1 and T 2 are reversed.

Slot 118 A includes bottom surface 146 connected to walls 142 and 144 . Key 114 A includes engagement surface 148 and resilient element 116 A is engaged with engagement surface 148 and bottom surface 146 to urge key 114 A in radial direction RD 1 .

In an example embodiment: sprocket 112 includes radially innermost surface 150 with grooves 152 A and 152 B circumferentially disposed about at least a portion of surface 150 , that is, between slots 118 , and separated in axial direction AD 1 ; key 114 A includes grooves 154 A and 154 B; and assembly 104 includes snap ring 156 A disposed in grooves 152 A and 154 A and snap ring 156 B disposed in grooves 152 B and 154 B. Snap rings 156 A and 156 B urge key 114 A in direction RD 2 , for example to hold key 114 A in place when assembly 104 is not disposed about shaft 102 .

In an example embodiment, assembly 104 includes cover plates 158 A and 158 B fixedly secured to sprocket 112 by any means known in the art. Key 114 A is restrained in directions AD 1 and AD 2 by cover plates 158 A and 158 B, while remaining displaceable in directions RD 1 and RD 2 with respect to cover plates 158 A and 158 B. In some applications of assembly 100 , cover plates 158 A and 158 B act as thrust washers.

Although assembly 100 is shown with a particular number and configuration of components, it should be understood that assembly 100 is not limited to a particular number and configuration of components. For example, assembly 100 can include a single indentation 110 , a single key 114 , a single element 116 and a single slot 118 . For example, assembly 100 can include more than two each of indentations 110 , keys 114 , elements 116 and slots 118 . Further, indentations 110 and slots 118 can be circumferentially disposed and spaced in configurations other than that shown in the figures.

FIG. 8 illustrates torque transmitting assembly 100 in a torque converter/transmission configuration.

FIG. 9 is a block diagram of torque transmitting assembly 100 in a torque converter/transmission configuration. In an example embodiment, shaft 102 is an input shaft for transmission T. As part of the connection of torque converter TC to transmission T including shaft 102 , bushings 202 and 204 must be fixed to shaft 102 so that when torque converter TC is connected to transmission T, housing 206 for the torque converter and stator shaft support 208 of the transmission engage bushings 202 and 204 , respectively. Shaft 102 rotates with respect to housing 206 and support 208 , and bushing 202 and 204 provide wear and friction reduction as well as seals.

As noted above, known techniques and components cannot be used to install a sprocket in the location shown in FIG. 8 because: a key on the shaft would prevent installation of bushings 202 and 204 ; a groove in the shaft would provide a leakage path past bushings 202 and 204 , and welding would prevent removal of the sprocket for disassembly of the transmission. Advantageously, assembly 100 provides the means for installing a sprocket as shown in FIG. 8 , without interfering with installation of bushings or providing leakage paths, and while enabling removal of the sprocket for disassembly operations.

Specifically, in one example, assembly 104 is inserted over one end of shaft 102 , for example, end LE 1 . Due to the relationship of diameters D 1 and D 2 , assembly 104 fits over shaft 102 and can be pushed in direction AD 1 towards indentation 110 . As assembly 104 slides along shaft 102 in direction AD 1 , keys 114 A and 114 B are urged against the shaft by elements 116 A and 116 B, respectively, and the shaft pushes the keys in direction RD 2 against the urging of the resilient elements. As assembly 104 reaches portion 102 A, there are two possibilities. If keys 114 and indentations 110 are circumferentially aligned, keys 114 slide down end walls 134 into indentations 110 . If keys 114 and indentations 110 are not circumferentially aligned, assembly 104 or shaft 102 is rotated until indentations 110 are circumferentially aligned and the keys slide over side walls 130 or 132 into indentations 110 . Once keys 114 are in indentations 110 , assembly 104 and shaft 102 are non-rotatably connected. Thus, in the example sequence above, bushing 204 is installed, assembly 104 is engaged with indentations 110 , and bushing 202 is installed.

Advantageously, if disassembly of transmission T is required, assembly 104 can be pushed in either direction AD 1 or AD 2 so that keys 114 slide along end walls 136 or 134 , respectively, and are pushed in radial direction RD 2 . Once assembly 104 is in portion 102 B or 102 C, assembly 104 can be pushed in direction AD 2 or AD 1 , respectively, as required, for example, for removal from shaft 102 .

It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.