Apparatus for splining thin-wall power transmission sleeves

Thin-wall sleeve splining apparatus (10) is disclosed as including a loader (22) having a radially expandable mandrel (24) which is inserted within a dual ended thin-wall sleeve (14) to secure the sleeve in preparation for splining one of its ends (12,16). A rotatable loading spindle (26) supports the expandable mandrel (24) and is moved by an actuator (28) to position the sleeve over a toothed mandrel (20) whereupon a pair of toothed dies (18) are moved in opposite directions to mesh die and mandrel teeth with the sleeve therebetween to form the thin-wall splines. After the splining, the actuator (28) moves the loading spindle (26) away from the toothed mandrel (20) for unloading of the splined sleeve. In the preferred construction of the apparatus, the toothed forming dies are embodied by elongated die racks (18) that are slidably mounted by upper and lower bases (32,34) of a splining machine (30). An external collet (110) of the expandable mandrel (24) is radially expanded and contracted by a hydraulic operator (118) to provide clamping and unclamping of the sleeve. Two expandable mandrels (24,24') are disclosed to provide splining of both ends of the sleeve (14).

TECHNICAL FIELD 
This invention relates to apparatus for splining thin-wall power 
transmission sleeves by a rolling operation. 
BACKGROUND ART 
U.S. Pat. No. 3,982,415, which is assigned to the assignee of the present 
application, discloses a rolling operation for forming splines in 
thin-wall sleeves of power transmission members. This rolling operation is 
performed by mounting the thin-wall sleeve on a toothed mandrel that is 
located between a pair of toothed dies. Movement of the pair of dies in 
opposite directions as each other meshes the die and mandrel teeth with 
the sleeve therebetween so as to form the splines at diametrically 
opposite locations while the mandrel rotates in coordination with the die 
movement. Vehicle automatic transmissions conventionally incorporate the 
type of splined sleeve formed by this rolling process which is capable of 
performing the splining much more economically than impact splining that 
was previously utilized. One embodiment of the toothed mandrel disclosed 
by this patent is radially expandable so as to facilitate mounting and 
removal of the sleeve for the splining. 
U.S. Pat. No. 4,028,922, which is also assigned to the assignee of the 
present application, discloses dies having a particular toothed forming 
face construction for performing the thin-wall sleeve splining discussed 
above. These dies are disclosed as being either of the straight gear rack 
type or of a rotary type such as disclosed by U.S. Pat. No. 4,045,988 
which is also assigned to the assignee of the present application. 
U.S. Pat. No. 4,155,237, which is also assigned to the assignee of the 
present application, discloses a thin-wall sleeve splining machine of the 
type discussed above with an automatic loader used to mount and remove the 
sleeve from the mandrel. Loading and unloading members of the machine 
loader cooperate to move the sleeve onto the mandrel for the splining 
operation and to thereafter remove the splined sleeve in preparation for 
the next cycle. 
DISCLOSURE OF INVENTION 
An object of the present invention is to provide improved apparatus for 
forming end splines on one end of a dual ended thin-wall sleeve for 
transmitting torque. 
In carrying out the above object, apparatus constructed in accordance with 
the invention includes a pair of toothed dies mounted in spaced 
relationship to each other for movement in opposite directions and also 
includes an externally toothed mandrel mounted between the dies for 
rotation about a central axis. A loader of the apparatus includes a 
radially expandable mandrel which is inserted within the sleeve and 
radially expanded at a location spaced from the one end thereof in order 
to secure the sleeve. The apparatus also includes a loading spindle on 
which the expandable mandrel is mounted for rotation about the central 
axis. An actuator of the apparatus moves the loading spindle axially to 
position the one end of the sleeve over the toothed mandrel such that die 
movement meshes the die and mandrel teeth with the sleeve end therebetween 
to form thin-wall splines. After the spline forming is completed, the 
actuator moves the loading spindle axially away from the toothed mandrel 
for unloading of the splined sleeve. 
In the preferred construction disclosed, the apparatus includes first and 
second expandable mandrels for enabling both ends of the sleeve to be 
splined during successive splining operations. Each of the expandable 
mandrels includes an axially facing surface that axially engages the 
sleeve end opposite the sleeve end to be splined such that mounting of the 
sleeve on the expandable mandrel is performed in a manner that accurately 
locates the sleeve during the splining. One of the expandable mandrels 
includes an axially facing surface that engages an axial surface formed on 
the associated sleeve end inwardly from its extreme axial end surface, 
while the other expandable mandrel includes an axially facing surface that 
engages the extreme axial end surface of its associated sleeve end upon 
mounting. 
The preferred construction of the expandable mandrel includes an external 
collet that is radially expandable and has an inwardly facing cone 
surface. An operator of the expandable mandrel includes an operating 
member having an outwardly facing cone surface that engages the cone 
surface on the collet to provide radial expansion and contraction of the 
collet upon relative axial movement between the operating member and the 
collet. The operator of the expandable mandrel also preferably includes a 
hydraulically operated piston for axially moving the operating member to 
radially expand and contract the collet. A spring of the expandable 
mandrel biases the piston thereof to provide expansion of the collet for 
clamping of the sleeve to be splined. Hydraulic fluid supplied to the 
piston provides axial movement thereof against the spring bias in order to 
contract the collet for unclamping of the sleeve after the thin-wall 
splining has been performed. 
In the preferred construction disclosed, the apparatus also includes a 
loading member on which the loading spindle is rotatably mounted 
preferably by antifriction bearings. The loading member and the loading 
spindle cooperatively define a passage through which hydraulic fluid is 
fed to the hydraulic piston that controls axial movement of the piston and 
consequent radial expansion and contraction of the collet for securing and 
releasing the sleeve being splined. An actuator of the apparatus includes 
a cylinder that moves the loading member along the central axis toward and 
away from the toothed mandrel to provide the loading and unloading during 
the splining operation. Antifriction bearings are also utilized to 
rotatably support the toothed mandrel for the rotation that takes place 
during the splining of the sleeve. 
Either the toothed mandrel or the expandable mandrel includes a central 
axial projection, and the other mandrel includes a central axial hole that 
receives the projection upon movement of the expandable mandrel toward the 
toothed mandrel. Cooperation of the axial projection and the axial hole 
provides a concentric relationship of the mandrels during the spline 
forming to thereby ensure precise formation of the thin-wall splines. 
As disclosed, the dies are embodied by a pair of toothed die racks mounted 
in a spaced relationship to each other for movement in opposite directions 
along parallel paths. The externally toothed mandrel is mounted between 
the die racks for rotation about the central axis about which the splining 
takes place. Die rack movement meshes the die and mandrel teeth with the 
sleeve end therebetween to form the thin-wall splines. 
A machine embodying the apparatus includes upper and lower bases defining a 
workspace in which the splining is performed. The pair of toothed die 
racks are respectively mounted on the upper and lower bases in a 
vertically spaced relationship to each other for movement in opposite 
directions along parallel paths. The externally toothed mandrel is mounted 
by antifriction bearings within the workspace for rotation about the 
central axis about which the splining is performed. 
The objects, features, and advantages of the present invention are readily 
apparent from the following detailed description of the best mode for 
carrying out the invention when taken in connection with the accompanying 
drawings.

BEST MODE FOR CARRYING OUT THE INVENTION 
Referring to FIG. 1 of the drawings, thin-wall splining apparatus 
constructed in accordance with the present invention is generally 
indicated by reference numeral 10 and is operable to form thin-wall 
splines in one end 12 of a thin-wall metal sleeve 14 which also has a 
second end 16 on which splines are formed as is hereinafter more fully 
described. As seen in both FIGS. 1 and 2, splining apparatus 10 includes a 
pair of toothed dies 18 that are mounted in a spaced relationship to each 
other for movement in opposite directions. An externally toothed mandrel 
20 of the splining apparatus is illustrated in FIG. 3 and is mounted 
between the dies 18 as shown in FIGS. 1 and 2 for rotation about a central 
axis A. A loader 22 of the apparatus is illustrated in FIG. 1 and includes 
a radially expandable mandrel 24 which is inserted within the sleeve 14 
and radially expanded at a location spaced from the one sleeve end 12 in 
order to secure the sleeve in preparation for the splining operation. A 
rotatable loading spindle 26 mounts the expandable mandrel 24 and is 
supported for rotation about the central axis A in alignment with the 
toothed mandrel 20. An actuator 28 of the splining apparatus moves the 
loading spindle 26 axially along the central axis A to position the one 
end of the sleeve 14 over the toothed mandrel 20 such that movement of the 
dies 18 meshes the die and mandrel teeth with the sleeve end 12 
therebetween to form thin-wall splines. After such splining, the actuator 
28 moves the loading spindle 26 axially away from the toothed mandrel 20 
for unloading of the splined sleeve. 
Referring to FIG. 2, a machine 30 incorporating the splining apparatus 10 
includes upper and lower bases 32 and 34 that project forwardly from a 
rear connecting portion 36 to define a workspace 38 in which the splining 
is performed. Each of the upper and lower dies 18 is disclosed as an 
elongated die rack having teeth 40 spaced along the length thereof between 
its opposite ends. End retention lugs 42 of each die rack 18 are secured 
by associated bolted clamps 44 to a rack box 46 which is mounted as shown 
in FIG. 1 on a fixture 48 that is fixed on an associated slide 50. Each 
slide 50 is supported by a slideway 52 on the associated machine base 32 
or 34. Die racks 18 are thus mounted on the upper and lower bases 32 and 
34 in a vertically spaced relationship from each other. 
Referring to FIG. 2, a schematically indicated drive mechanism 54 of 
machine 30 is preferably of the type disclosed by U.S. Pat. No. 3,793,866 
and initially moves the die racks 18 along parallel paths in opposite 
directions as each other as indicated by arrows 56 so as to engage the 
sleeve 14 at diametrically opposite locations on opposite sides of the 
central axis A. Such movement of the die racks 18 meshes the die teeth 40 
and mandrel teeth 58 (FIG. 3) with the sleeve 14 therebetween in order to 
form thin-wall splines 60 on the end of the sleeve as illustrated in FIG. 
4. Thereafter, the machine drive mechanism 54 shown in FIG. 2 moves the 
die racks 18 in the opposite directions shown by arrows 62 back to their 
original position in preparation for the next cycle. 
With reference to FIG. 3, it should be noted that whereas normal 
engineering terminology defines a thin-wall construction as including an 
internal diameter "D" to wall thickness ratio "t" of at least ten, this 
ratio is at least twenty for the type of splining involved with this 
invention and normally on the order of fifty or more. For example, the 
internal diameter may be on the order of about 4 inches with a wall 
thickness of about 1/16 of an inch so as to provide a ratio of 64. 
As illustrated in FIG. 1, a loading indexer 62 is positioned between the 
toothed mandrel 20 and the expandable mandrel 24 and is preferably of the 
type disclosed by U.S. Pat. No. 4,155,237. Operation of loading indexer 62 
moves each sleeve 14 to be splined into alignment with the expandable 
mandrel 24 whereupon operation of the actuator 28 moves the expandable 
mandrel toward the left into the sleeve. Expansion of the mandrel 24 then 
secures the sleeve 14 in preparation for the splining. Actuator 28 then 
moves the mandrel 24 and the sleeve 14 toward the left such that the 
sleeve end 12 is positioned over the toothed mandrel 20 for the splining 
operation previously described. Thereafter, the actuator 28 moves the 
expandable mandrel 24 toward the right to transfer the splined sleeve 14 
back to the loading indexer 62 whereupon the expandable mandrel is 
contracted to release the splined sleeve and is then moved farther toward 
the right to the position shown. Operation of the loading indexer 62 then 
moves the splined sleeve 14 out of alignment with the expandable mandrel 
24 and concomitantly moves the next sleeve to be splined into alignment 
therewith in preparation for the next cycle. 
With continuing reference to FIG. 1, a hollow support housing 64 is secured 
in a fixed relationship by bolts 66 to the machine connecting portion 36 
projecting forwardly therefrom into the workspace 38. A hollow support 
housing extension 68 is secured by bolts 70 to support housing 64 and 
receives a forwardly projecting mandrel spindle 72. An antifriction roller 
bearing 74 and a dual row antifriction tapered roller bearing 76 cooperate 
to rotatably mount the mandrel spindle 72 on the support housing extension 
68 for rotation about the central axis A about which the sleeve splining 
is performed. A mandrel adapter 78 has an end 80 received within a hole 82 
in the mandrel spindle 72 and also has an annular flange 84. A mandrel 
synchronizing gear 86 is secured by bolts 88 to the flange 84 of the 
mandrel adapter 78 and is meshed with a pair of synchronizing racks 90 
carried by the slide fixtures 48 on which the forming die racks 18 are 
also supported. The externally toothed mandrel 20 is also secured by a 
plurality of bolts 92 to the annular flange 84 of the mandrel adapter 78 
so as to be supported thereby for rotation about the central axis A. It 
will be noted that rack spacers 94 position the forming die racks 18 on 
the rack boxes 46 so as to be aligned with the toothed mandrel 20 in order 
to provide the thin-wall sleeve forming as previously described. During 
the splining, the synchronizing gear 86 and synchronizing racks 90 
cooperate to rotate the toothed mandrel 20 in coordination with the 
forming racks 18 to provide the tooth meshing that forms the thin-wall 
splines. 
With combined reference to FIGS. 1 and 5, the expandable mandrel 24 
includes an axially facing surface 96 that engages the sleeve end 16 at an 
axially facing surface 98 thereof located inwardly from the extreme axial 
end surface 100 of the sleeve end 16. As disclosed, the sleeve end 16 is 
formed outwardly to provide an annular end ring 102 of a greater diameter 
than the rest of the sleeve with the axially facing surface 98 extending 
between the end ring and the rest of the sleeve. After the sleeve end 12 
has been splined with the expandable mandrel 24 supporting the sleeve end 
16 during the splining, the splined end 12 is then supported by another 
expandable mandrel 24' shown in FIG. 6 in preparation for forming 
thin-wall splines 60 on the sleeve end 16. To facilitate production, 
normally there will be two machines, one of which is utilized to provide 
the splining of the sleeve end 12 and the other of which is used to 
provide the splining of the sleeve end 16. Thus, the mandrel 24 shown in 
FIG. 1 will be mounted on one of the machines while the mandrel 24' shown 
in FIG. 6 will be mounted on the other machine. 
Expandable mandrel 24 shown in FIG. 1 and the expandable mandrel 24' shown 
in FIG. 6 have generally the same construction as each other, except as 
will be noted, and thus will be described together with like reference 
numerals applied to like components of each mandrel. As illustrated in 
FIG. 6, each expandable mandrel includes an adapter 104 that is secured by 
a plurality of circumferentially spaced bolts 106 (only one shown) to an 
annular flange 108 of the loading spindle 26. An external collet 110 of 
the expandable mandrel has an annular configuration and is engaged with an 
axially facing surface 112 on the adapter 104. As illustrated in FIG. 7, 
collet 112 has axially extending slots 114 extending alternately from its 
opposite axial sides so as to be radially expandable to provide sleeve end 
clamping upon insertion into the sleeve as illustrated in FIG. 6. 
As seen in FIG. 6, the collet 110 of mandrel 24' has a slightly smaller 
diameter than the axially facing surface 112 on the adapter 104 such that 
the adapter axially engages the sleeve end 12 to provide proper 
positioning thereof in preparation for the splining operation on the other 
sleeve end 16. Collet 110 of mandrel 24 shown in FIG. 1 has a slightly 
larger size than the adapter 104 and defines the axially facing surface 96 
that engages the axial sleeve end surface 98 as previously described. Such 
axial engagement of each mandrel with the sleeve 14 accurately locates the 
sleeve during the splining operation. 
External collet 110 shown in FIG. 6 has an inwardly facing cone surface 116 
that converges toward the right in a concentric relationship with the 
central axis A about which the loading spindle 26 is rotatably supported. 
An operator 118 of the expandable mandrel includes an operating member 120 
that is located within the collet 110 and has an outwardly facing cone 
surface 122 engaged with the cone surface 116 on the collet. As is 
hereinafter more fully described, mandrel operator 118 moves the operating 
member 120 axially to provide radial expansion and contraction of collet 
110. Movement of the operating member 120 toward the right provides the 
radial expansion of the collet 110 in order to provide clamping of the 
sleeve 14 for the thin-wall splining. Thereafter subsequent to completion 
of the splining, the operating member 120 is moved toward the left in 
order to provide contraction of the collet 110 for unclamping of the 
sleeve 14. 
With continuing reference to FIG. 6, the operator 118 of the expandable 
mandrel also includes a housing having a first member 123 that is secured 
by a plurality of bolts 124 (only one shown) to the mandrel adapter 104. A 
second member 126 of the mandrel housing is secured by a plurality of 
bolts 128 to the first housing member 123 to cooperate therewith in 
defining a piston chamber 130. Operator 118 also includes a hydraulically 
operated piston 132 that is received within the chamber 130 defined by the 
housing members 123 and 126. A plurality of circumferentially spaced 
piston extensions 134 (only one shown) extend from the piston 132 to 
engage the operating member 120 in order to provide movement thereof in 
response to movement of the piston. A plurality of helical springs 136 
bias the piston 132 toward the right in order to provide the axial 
movement of the operating member 120 toward the right for expansion of the 
collet 110. 
Upon hydraulically actuated movement of the piston 132 toward the left as 
viewed in FIG. 6, a plurality of circumferentially spaced helical springs 
138 (only one shown) extending between the adapter 104 and the operating 
member 120 provide movement of the operating member toward the left in 
order to permit contraction of the collet 110 for unclamping of the sleeve 
after the splining has been performed. A guide pin 140 on the operating 
member 120 extends into a hole 141 in the first housing member 123 in 
order to guide movement and prevent rotation of the operating member with 
respect to the housing and the collet. Suitable keys may also be provided 
between the collet 110 and both the adapter 104 and the operating member 
120 in order to prevent relative rotation of the collet. 
Piston 132 of the expandable mandrel shown in FIG. 6 includes an annular 
seal 142 and its extension 134 includes a seal 144 so as to prevent 
leakage of hydraulic fluid during operation which is more fully 
hereinafter described. Loading spindle 26 and the first housing member 123 
include associated annular seals 146 and 148 which are engaged with the 
mandrel adapter 104 within a central hole 150 through which the central 
axis A extends. Also, the second housing member 126 of the expandable 
mandrel includes a central hole 152 that receives a guide 154 of the 
piston 132 to provide a guiding action thereto during the piston movement. 
With reference to FIG. 1, a loader base 156 is mounted in front of the 
indexer 62 and supports a hollow slideway 158 that defines a central 
opening 160 aligned with the central axis A of rotation. A loading member 
162 which preferably has a tubular shape is received within the slideway 
opening 160 and is supported by a pair of bushings 164 for axial movement 
that moves the expandable mandrel 24 toward the left and the right as 
previously described. At its left end, loading member 162 includes a pair 
of tapered antifriction roller bearings 165 that rotatively support the 
loading spindle 26 on which the expandable mandrel 24 is mounted. The 
interior 166 of loading member 162 and a central axial hole 168 through 
the loading spindle 26 cooperate to define a passage through which 
hydraulic fluid is fed from a suitable source to control movement of the 
hydraulic piston. As best seen in FIG. 6, this hydraulic fluid is fed 
through a hole 170 in the first housing member 123 of the expandable 
mandrel to operate the piston 132 in the manner previously described. 
With reference back to FIG. 1, the right end of the loading member 162 has 
a suitable schematically indicated connection 172 to the actuator 28 which 
preferably includes a cylinder 174 that is mounted on top of the slideway 
158 and secured thereto by bolts 176. Cylinder 174 has a piston connecting 
rod 178 that extends outwardly therefrom and is secured to the connection 
172 to the loading member 162. As such, extension and retraction of the 
cylinder rod 178 moves the loading member 162 to provide axial movement of 
the expandable mandrel 24. 
As seen in FIG. 1, the toothed mandrel 20 includes a projection 180 that is 
received within the central axial hole 152 in the expandable mandrel 24 
upon movement of the expandable mandrel toward the left for loading of the 
sleeve 14 in preparation for the splining operation previously described. 
This inserted relationship of the toothed mandrel projection 180 into the 
hole 152 of the expandable mandrel 24 provides a concentric relationship 
of the mandrels during the spline forming to ensure precision in the 
thin-wall splines that are produced. Of course, it is possible to reverse 
the respective positions of the projection and the hole on the two 
mandrels and still produce the same concentric relationship of the two 
mandrels. 
While the best mode for carrying out the invention has been described in 
detail, those familiar with the art to which this invention relates will 
recognize various alternative designs and embodiments for practicing the 
invention as defined by the following claims.