U.S. patent application number 13/311934 was filed with the patent office on 2013-06-06 for slip joint and method for assembling the same.
This patent application is currently assigned to Dana Automotive Systems Group, LLC. The applicant listed for this patent is Johnny N. Smith. Invention is credited to Johnny N. Smith.
Application Number | 20130143678 13/311934 |
Document ID | / |
Family ID | 48524398 |
Filed Date | 2013-06-06 |
United States Patent
Application |
20130143678 |
Kind Code |
A1 |
Smith; Johnny N. |
June 6, 2013 |
Slip Joint and Method for Assembling the Same
Abstract
A slip joint comprising, a female portion comprised of four
axially extending segments. The segments together create an outer
perimeter. Each of the combined segments together form an inner
surface of the female portion and each has its own ball tracks
extending substantially the length of the female portion. A unitary
male portion has an outer surface defined by a plurality of axially
extending ball tracks. A unitary cage is located radially outward
from the male portion and radially inward from the female portion.
The cage has a plurality of ball apertures with balls located in
the ball apertures. The balls are in contact with both the ball
tracks in the male and female portions for selective movement of
the male portion with respect to the female portion. A tube member
is in direct radial outer contact substantially entirely along the
outer perimeter of the female portion.
Inventors: |
Smith; Johnny N.; (Toledo,
OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Smith; Johnny N. |
Toledo |
OH |
US |
|
|
Assignee: |
Dana Automotive Systems Group,
LLC
Maumee
OH
|
Family ID: |
48524398 |
Appl. No.: |
13/311934 |
Filed: |
December 6, 2011 |
Current U.S.
Class: |
464/167 ;
29/428 |
Current CPC
Class: |
F16C 29/04 20130101;
F16D 2300/12 20130101; Y10T 29/49826 20150115; F16C 3/035 20130101;
Y10T 29/49641 20150115; F16D 3/065 20130101 |
Class at
Publication: |
464/167 ;
29/428 |
International
Class: |
F16D 3/06 20060101
F16D003/06; B23P 11/00 20060101 B23P011/00 |
Claims
1. A slip joint, comprising: a female portion comprised of four
axially extending segments of substantially equal length, wherein
two segments comprise a first pair of identical segments and two
other segments comprise a second pair of identical segments
different than said first pair, wherein said segments in said first
pair comprise a greater portion of an outer perimeter of said
female portion than said segments in said second pair and wherein
said segments in said first pair alternate with said segments in
said second pair, said four segments together creating said outer
perimeter with spaced apart grooves extending circumferentially
around all four segments of said female portion, said outer
perimeter also comprising a unitary radially extending tube stop,
wherein each of said combined segments together form an inner
surface of said female portion and wherein each of said segments
each have at least one axially extending ball track, said ball
track extends substantially the length of said female portion; a
unitary male portion having an outer surface defined by a plurality
of axially extending ball tracks, said ball tracks are parallel
with the axis of the male portion, are parallel to one another, and
are aligned with said ball tracks on said female portion, said male
portion located radially inward said female portion inner surface;
a unitary cage located radially outward from said male portion
outer surface and radially inward said female portion inner
surface, said cage having an inner surface and an outer surface,
wherein said cage has a plurality of ball apertures each extending
entirely through from said inner surface to said outer surface,
said ball apertures aligned in rows complementary to said ball
tracks in said male and female portions; a plurality of balls
located in said plurality of ball apertures, said balls in contact
with both of said ball tracks in said male and female portions for
selective movement of said male portion with respect to said female
portion; and a tube member having an inner surface and an outer
surface in direct radial outer contact substantially entirely along
said outer perimeter of said female portion, said tube member
having an end directly abutting an interior edge of said tube
stop.
2. A slip joint according to claim 1, wherein said segments in said
first pair do not directly contact one another and said segments in
said second pair do not directly contact one another.
3. A slip joint according to claim 1, wherein at least one
circumferential member is selectively located in said outer
perimeter of same female portion spaced apart grooves to secure
said four segments together.
4. A slip joint according to claim 1, wherein a gap is located
between said outer surface of said male portion and said inner
surface of said female portion.
5. A slip joint according to claim 1, wherein said inner surface
and said outer surface of said tube member define a substantially
constant thickness between them.
6. A slip joint, comprising: a female portion comprised of four
axially extending segments of substantially equal length, wherein
two segments comprise a first pair of identical segments and two
other segments comprise a second pair of identical segments
different than said first pair, wherein said segments in said first
pair comprise a greater portion of an outer perimeter of said
female portion than said segments in said second pair and wherein
said segments in said first pair alternate with said segments in
said second pair, said four segments together creating said outer
perimeter with spaced apart grooves extending circumferentially
around all four segments of said female portion, said outer
perimeter also comprising a unitary radially extending tube stop,
wherein each of said combined segments together form an inner
surface of said female portion and wherein each of said segments
each have at least one axially extending ball track, said ball
track extends substantially the length of said female portion; a
unitary male portion having an outer surface defined by a plurality
of axially extending ball tracks, said male portion located
radially inward said female portion inner surface; a unitary cage
located radially outward from said male portion outer surface and
radially inward said female portion inner surface, said cage having
an inner surface and an outer surface, wherein said cage has a
plurality of ball apertures each extending entirely through from
said inner surface to said outer surface; a plurality of balls
located in said plurality of ball apertures, said balls in contact
with both of said ball tracks in said male and female portions for
selective movement of said male portion with respect to said female
portion; and a tube member.
7. A slip joint according to claim 6, wherein there is the same
number of axially extending ball tracks on said male portion as
ball tracks on said female portion.
8. A slip joint according to claim 6, wherein said male portion and
said female portion ball tracks are aligned with one another.
9. A slip joint according to claim 6, wherein a gap is located
between said outer surface of said male portion and said inner
surface of said female portion.
10. A slip joint according to claim 6, wherein said ball apertures
are aligned in rows complementary to said ball tracks in said male
and female portions.
11. A slip joint according to claim 6, wherein said tube member has
an inner surface and an outer surface, said inner surface being in
direct radial contact substantially entirely along said outer
perimeter of said female portion.
12. A slip joint according to claim 6, wherein said tube member has
an end directly abutting an interior edge of said tube stop.
13. A method of assembling a slip joint, comprising: providing a
first pair of identical segments which together comprise only part
of a circumference of a female portion, wherein at least one ball
track extends substantially along inner surfaces of each of said
first pair of identical segments; providing a second pair of
identical segments which together comprise only part of said
circumference of said female portion, wherein at least one ball
track extends substantially along inner surfaces of each of said
second pair of identical segments; joining said first pair of
identical segments with said second pair of identical segments to
comprise said circumference of said female portion wherein said
first pair of identical segments comprise a larger percentage of
said circumference than said second pair of identical segments;
locating said joined first and second pair of segments within a
tube member so that an outer surface of said joined segments is in
direct contact with an inner surface of said tube member; locating
a male member radially inward said ball tracks of said first and
second pair of segments, said male member having ball tracks
extending substantially along an outer surface of said male member
and in alignment with said ball tracks of said first and second
pair of segments; permitting said male and female members to
selectively move axially with respect to one another by locating a
cage between them, said cage holding a plurality of balls that roll
within said ball tracks of said male and female members.
14. (canceled)
15. A method of assembling a slip joint according to claim 13,
wherein said second pair of identical segments do not directly
contact one another and said first pair of identical segments do
not directly contact one another.
16. A method of assembling a slip joint according to claim 13,
wherein circumferential members are selectively located around said
circumference of said female portion to secure said segments
together.
17. A method of assembling a slip joint according to claim 13,
wherein there is the same number of axially extending ball tracks
on said male portion as ball tracks on said female portion.
18. A method of assembling a slip joint according to claim 13,
wherein said male portion and said female portion ball tracks are
aligned with one another.
19. A method of assembling a slip joint according to claim 13,
wherein a gap is located between the outer surface of the male
portion and the inner surface of the female portion.
20. A method of assembling a slip joint according to claim 13,
wherein said cage has a plurality of ball apertures aligned in rows
complementary to said ball tracks in said male and female
portions.
21. A method of assembling a slip joint according to claim 13,
wherein said inner surface of said tuber member and an outer
surface of said tube member define a substantially constant
thickness between them.
Description
RELATED APPLICATIONS
[0001] None
FIELD OF THE INVENTION
[0002] The present invention relates to an improved structure for a
rolling element spline type of slip joint for use in a vehicle.
BACKGROUND OF THE INVENTION
[0003] Slip joints are used for transmitting rotational force or
torque between telescoping members, while accommodating relative
axial movement there between. This is most commonly used in vehicle
drive train systems. Drive train systems are generally used for
generating power from a source and for transferring such power from
the source to a driven mechanism.
[0004] The typical drive train system includes a driveshaft
assembly that is connected between an output shaft of an
engine/transmission assembly and an input shaft of an axle
assembly. The driveshaft assembling includes universal joints which
provide a rotational driving connection from an output shaft of an
engine/transmission assembly to an input shaft of an axle assembly,
while accommodating a limited amount of angular misalignment
between the rotational axes.
[0005] Not only must the drive train assembly accommodate a limited
amount of angular misalignment between the engine/transmission
assembly and the axle assembly, but it must also accommodate a
limited amount of relative axial movement. The axial movement
frequently occurs when the vehicle is operated. Typically slip
joints are used to address the issue of axial movement. A typical
slip joint includes male and female telescoping members. The male
and female members each have a plurality of extending splines. To
assemble the slip joint, the male member is inserted within the
female member such that the splines of the male member cooperate
with the splines of the female member. The cooperating splines of
the respective members provide a rotational driving connection
though the slip joint, while also permitting a limited amount of
relative axle movement there between.
[0006] In the past, the splined members have been formed by a
machining process, wherein material was removed from the members.
While this process is satisfactory, is has been found to be
somewhat inefficient. Thus it would be desirable to provide an
improved method for manufacturing the splined members. It would be
advantageous to produce a female member that has a simple profile
that is easily controlled in a high volume production
environment.
SUMMARY OF THE INVENTION
[0007] A slip joint has a female portion comprised of four axially
extending segments of substantially equal length. Two of the
segments comprise a first pair of identical segments and two other
segments comprise a second pair of identical segments, different
than the first pair. The segments in the first pair comprise a
greater portion of an outer perimeter of the female portion than
the segments in the second pair. The segments in the first pair
alternate with the segments in the second pair, and the four
segments together create an outer perimeter with spaced apart
grooves extending circumferentially around all four segments of the
female portion. The outer perimeter also comprises a radially
extending tube stop. Each of the combined segments together form an
inner surface of the female portion and each of the segments have
their own ball tracks extending axially, substantially the length
of the female portion. A unitary male portion has an outer surface
defined by a plurality of axially extending ball tracks, the same
number as the ball tracks on the female portion. The male portion
and the female portion ball tracks are aligned with one another.
The male portion is located radially inward the female portion
inner surface. A unitary cage is located radially outward from the
male portion outer surface and radially inward from the female
portion inner surface. The cage has an inner surface and an outer
surface. The cage also has a plurality of ball apertures each
extending entirely through from the inner surface to the outer
surface. The ball apertures are aligned in rows complimentary to
the ball tracks in the male and female portions. A plurality of
balls are located in the plurality of ball apertures. The balls are
in contact with both the ball tracks in the male and female
portions for selective movement of the male portion with respect to
the female portion. A tube member having an outer surface and an
inner surface, which is in direct radial contact substantially
entirely along the outer perimeter of said female portion. The tube
member has an end directly abutting an interior edge of the tube
stop on the female portion.
[0008] Various objects and advantages of this invention will become
apparent to those skilled in the art from the following detailed
description of the preferred embodiments, when read in light of the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The above, as well as other advantages of the present
invention, will become readily apparent to those skilled in the art
from the following detailed description when considered in the
light of the accompanying drawings in which:
[0010] FIG. 1 is a side view of one embodiment of the present
invention;
[0011] FIG. 2 is a partial cut-away view of a portion of the
embodiment of FIG. 1 along line 2-2;
[0012] FIG. 3 is a perspective exploded view of the embodiment of
FIG. 2;
[0013] FIG. 4 is a cross-sectional view of a portion of the
embodiment of FIG. 1 along line 4-4;
[0014] FIG. 5 is a cross-sectional view of a portion of the
embodiment of FIG. 2 along line 5-5; and
[0015] FIG. 6 is an assembled view of the embodiments depicted
above.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] It is to be understood that the invention may assume various
alternative orientations and step sequences, except where expressly
specified to the contrary. It is also to be understood that the
specific devices and processes illustrated in the attached
drawings, and described in the following specification are simply
exemplary embodiments of the inventive concepts defined in the
appended claims. Hence, specific dimensions, directions or other
physical characteristics relating to the embodiments disclosed are
not to be considered as limiting, unless the claims expressly state
otherwise.
[0017] Referring now to FIGS. 1 and 2, a slip joint 10 is depicted
having a segmented female portion 12. The female portion 12 of the
slip joint 10, as shown in detail in FIG. 3, is comprised of four
axially extending segments 14, 16, 18, 20 of substantially equal
length. It is also within the scope of the present invention for
there to be more or less axially extending segments as may be
required for a specific application.
[0018] As shown in FIGS. 3, 4, and 5, two of the segments 14, 16
comprise a first pair of identical segments and two other segments
18, 20 comprise a second pair of identical segments different than
the first pair. Once assembled in the slip joint 10, the segments
14, 16 in the first pair do not directly contact one another and
the segments 18, 20 in the second pair do not directly contact one
another. Accordingly, the segments in the first pair 14, 16
alternate with the segments in the second pair 18, 20 in the slip
joint 10. The four segments 14, 16, 18, 20 together create an outer
perimeter 22. The segments in the first pair 14, 16 comprise a
greater portion of the outer perimeter 22 of the female portion 12
than the segments in the second pair 18, 20, as depicted in FIGS. 4
and 5.
[0019] The outer perimeter 22 of the female portion 12 is
substantially smooth and curvilinear with the exception of at least
one groove 24 extending circumferentially around all four of the
segments 14, 16, 18, 20 of the female portion 12, and a tube stop
28. As shown in FIGS. 2 and 3, at least two spaced apart grooves 24
are shown, however, it is within the scope of the invention for
there to be more or less grooves as needed.
[0020] As shown in FIGS. 3 and 6, circumferential members 26 are
selectively located in the grooves 24. The circumferential members
26 may be C-shaped clamps that are compressed within the grooves 24
to secure the segments 14, 16, 18, 20 together. It should also be
understood that there are other means of securing the segments
together which may include but is not limited to mechanical
fasteners and/or welding and/or adhesives and/or male/female
couplings and/or keyways, to name a few.
[0021] One end on each of the segments 14, 16, 18, 20, as depicted
in FIGS. 2 and 3, comprises a unitary radially extending tube stop
28. The tube stop 28 extends radially outward from the outer
perimeter 22 forming a 90 degree angle 30 along an interior
abutting edge 32. An exterior sloped edge 34 of the tube stop 28 is
provided, as best shown in FIG. 2. Also as shown in FIG. 2, an
inner surface 36 of the tube stop 28 comprises a cut-out area for
accepting a seal assembly 38. The seal assembly 38 is located
radially inward from the tube stop 28 and the exterior sloped outer
edge 34.
[0022] Each of the combined segments 14, 16, 18, 20 together form
an inner surface 40 of the female portion 12, and each of the
segments 14, 16, 18, 20 have their own balls tracks 42, as shown in
FIG. 3, extending substantially the length of the female portion
12. The ball tracks 42 are parallel with the axis of the female
portion 12. The ball tracks 42 are also parallel to one another and
equally spaced about the female portion 12. As depicted in FIGS. 4
and 5, each segment 14, 16, 18, 20 comprises two tracks each.
However, it is within the scope of the invention for there to be
more or less tracks in each segment.
[0023] The segments 14, 16, 18, 20 are produced with complimentary
mating surfaces with each other, and may be cold formed, forged,
extruded or powered metal. By producing the female portion 12 in
this manner, it is possible to harden and grind the working
surfaces (inner surface 40 and ball tracks 42), economically, which
will improve durability. Each segment 14, 16, 18, 20 has a simple
profile that is easily controlled in a high volume production
environment.
[0024] A unitary male portion 44, as shown in FIG. 3, comprises an
outer surface 46 defined by a plurality of axially extending,
circumferentially spaced apart ball tracks 48. The ball tracks 48
extend substantially the length of the male portion 44. The ball
tracks 48 are parallel with the axis of the male portion 44. The
ball tracks 48 are also parallel to one another and equally spaced
and aligned with the ball tracks 42 of the female portion 12. The
ball tracks 48 are equal in number to the ball tracks 42 of the
female portion 12.
[0025] The male portion 44 is located radially inward of the female
portion inner surface 40. The outer surface 46 of the male portion
44 and the inner surface 40 of the female portion 12 maintain a
substantially constant gap 50 between the two surfaces, as depicted
in FIG. 4. The gap 50 is substantially equidistant along the length
of the male and female portions 44, 12.
[0026] As depicted in FIGS. 3 and 4, a unitary cage 52 is located
radially outward from the male portion outer surface 46 and
radially inward the female portion inner surface 40, and within the
gap 50. The cage 52 has an inner surface 54 and an outer surface
56. A plurality of ball apertures 58 each extends entirely through
from the inner surface 54 to the outer surface 56 of the unitary
cage 52. The ball apertures 58 are aligned in rows complimentary to
the ball tracks 48 in the male portion 44 and the ball tracks 42 in
the female portion 12.
[0027] A plurality of balls 60, as depicted in FIGS. 2, 4 and 5,
are located in the plurality of ball apertures 58, wherein the
balls 60 are in contact with the ball tracks in both the male and
the female portions 48, 42 for selective axial movement of the male
portion 44 with respect to the female portion 12.
[0028] As depicted in FIG. 6, a tube member 62 having an inner
surface 64 and an outer surface 66 is provided. The inner surface
64 is in direct radial contact substantially entirely along the
outer perimeter 22 of the female portion 12, and ending at and
abutting the interior abutting edge 32 of the tube stop 28. The
inner surface 64 and the outer surface 66 of the tube member 62 is
substantially parallel and coplanar with a top edge of the tube
stop 28.
[0029] As shown in the assembled view of FIG. 6, the slip joint
comprises the first pair of identical segments 14, 16 alternated
and interlocked between the second pair of identical segments 18,
20. The joined segments 14, 16, 18, 20 form the outer perimeter 22
and the inner surface 40 of the female portion 12. Each of the
segments 14, 16, 18, 20 comprises ball tracks 42 extending
substantially the length of the female portion 12.
[0030] The male portion 44 is located radially inward of the inner
surface 40 of the female portion 12. The male portion 44 comprises
a plurality of ball tracks 48 extending substantially along the
outer surface 46 of the male portion 44. The ball tracks 42 of the
female portion 12 and the ball tracks 48 of the male portion 44 are
aligned with one another so that the male and female portions 44,
12 may selectively move with respect to one another by locating a
cage 52 between them.
[0031] The cage 52 comprises a plurality of ball apertures 58 for
holding a plurality of balls 60 that roll within the ball tracks 42
of the female portion 12 and the ball tracks 48 of the male portion
44.
[0032] The joined segments 14, 16, 18, 20 located racially outward
of the male portion 44 are pressed within a tube member 62 so that
the outer perimeter 22 of the female portion 12 is in direct
contact with the inner surface 64 of the tube member 62. This
provides the slip joint 10 with the added hoop strength it needs to
transmit torque.
[0033] In accordance with the provisions of the patent statutes,
the present invention has been described in what is considered to
represent its preferred embodiments. However, it should be noted
that the invention can be practiced otherwise than as specifically
illustrated and described without departing from its spirit or
scope.
* * * * *