Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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Description
Tools for Disassemblinq Universal Joints
S Technical Field
The present invention relates to tools for
disassembling univexsal joints, and more specifically
to two different types of kools -- a pull-type tool
and a push-type tool -- for disassembling universal
~0 jolnts of vehicles.
Backqround Art
There are various situations in whi~h it is
necessary to disassemble the universal joint of the
drive shaft of a vehlcle. For 2xample, prior to
towing a vehicle with the drive wheels remaining on
the ground, it is necessary to disconnect the
transmission ~rom the drive axles to protect the
vehicle from damage during towing. This is generally
achieved by disconnecting the drive shaft universal
joint at the drive axle pinion yoke, or occasionally
by pulling the drive axle shafts. However,
substantial problems are often encountered when
disassembling the universal ~oint.
Specifically, although new universal joint
components are shiny and have accurately machined
fits, and can be assembled easily, even when in dry
condition, once a vehicle has been used for a year or
more without di~assembling ths drive shaft universal
joint, the universal joint soon becomes rusted due to
wet roads and/or salty roads, so that the universal
joint components become so tightly assembled that it
is virtually impossible to disassemble them.
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Faced with ~uch a problem, mechanics and
towing/wrecker crews often r~sort to hammering the
universal joint components apart, but that is very
destructive to the components. In addition, even
that technique is often not effective or is difficult
to carry out, especially when it has to be done at
night on cold, wet roads with merely a flashlight as
a light source. The problems are further compounded
by the fact that, in towing situations, there is
u~ually very little room in which to work.
In response to the ab~ve-discussed
problems, a mechanical puller apparatus for
disa~sembling universal joints has been developed,
: and is disclosed in U.S. Patën't'' No.~--4,019,233
Jirele. The apparatus or tool disclosed in that
~; patent employs a driver screw which is rotated
mechanically or manually to exert a downward force on
a bridge assembly connected to a first yoke member of
the universal joint, while an upward pulling force is
exerted on bosses connected to the second yoke member
~: of the universal joint by means of puller arms which
are threadably connected to the driver screw.
: Small hand pullers of the type described in
the aforementioned patent have significant drawbacks.
Notably, since such pullers are operated by manual
force, their effectiveness varies from user ~o user,
and often they are ineffective to do the job. In
addition, such small hand pullers are not efective
for the purposes of towing and wrecker crews, in that
working conditions on the road (poor lighting,
inclement weather, insufficient working space, and so
forth) render manual pullers even less effective.
A further disadvantage of'the manual puller
described in the aforementioned patent resides in the
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fack that, in the use of ~uch a "rotatirlg screw"
tool, many unwanted reaction forces are produced when
the scxew 1~ rotated manually, and this interferes
with the successful accomplishment of the univer~al
joint disassembly operation. This problem, together
with the afor~mentioned problems of poor working
conditions, re~ults in the consumption of excessive
time as the user attempts to disassemble the
universal joint. Finally, it will be recognized that
1~ puller-type tools ~uch as disclosed in the
aforementioned patent are bulky, and this is a
disadvantage not only from the standpoint o~ using
the tool, but also from the ~tandpoint of
transporting the tool to the worksite.
Large, industrial-type tools are available
in the marketplace, and are used for pulling
assembled components apart, or pushing components out
of an assembly. Such large, industrial-type tools
often employ electric motors or pneumatic-powered
hydraulic power packs, and occasionally handpowered
units are employed in conjunction with closed
hydraulic circuits. The following U.S. patents
disclose ~uch types of hydraulic-powered apparatus or
arrangements: 2,807,081 Black; 3,069,761 - Sommer;
and 3,908,258 - Barty.
However, such powered apparatus or
arrangements are burdened by several disadvanta~es.
They are usually very large and b~lky, and are
therefore not suitable for transport to and from
towing or wrecker worksites, and are al~o not
suitable for use under the adverse conditions often
encountered by towing and wrecker crews. ~n
addition, such industrial-type powered apparatus
often operate under hydraulic power, and accordingly
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require auxiliary hydraulic sources to power their
operation, thus increasing their bulkiness and non-
portability. Finally, such apparatus or arrangements
as disclosed in the latter three patents are simply
not suitable or adaptable for use in the ~pecific
application of disassembling universal joints.
Other disassembly or pushing-pulling tools
or apparatus, ~ven less applicable to the job of
disassembling drive shaft universal ~oints, are
10disclosed in the following U.S. patents: ~,950,525 -
Duncan et al; 3,337,943 - Powell; 3,339,263 - Dodge;
1,498,933 - Seppmann; 2,507,003 - Gagne; 2,566,847 -
~iller; 3,230,617 - Spiess et al; 3,927,462 - Freeman
et al; and 4,182,011 - Bretzger-et al.
15To summarize, the state of the prior art in
this area of technology is such that it would be
considered highly desirable and advantageous to have
a tool or apparatus which is specifically designed
for the disassembly of drive shaft universal joints,
especially under adverse road conditions as usually
encountered by towing and wrecker crews. Such drive
shaft universal joint disassembly tools should have
the following characteristics: they should be
portable and easily transportable to the worksite;
they should be powered so as to ~acilitate their use,
e~pecially under conditions of limited space and
adverse working conditions; and they should be
powered by some power source normally available to
towing and wrecker crews at the worksite.
Disclosure of Invention
The present invention relates to tools for
disassembly of a drive shaft univer6al joint, and
~ore specifically to pull-type and push-type tools
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for disassembly of a universal joint of a drive
shaft.
In one embodiment, a pull-kype tool is
utilized to disassemble a universal joint by forcing
one of two journal bearings mountad in respective end
portions of a first yoke member out of the first yoke
member. The pull-type tool compri~es a pulling
arrangement connectable to the 6econd yoke member of
the universal joint for exerting a pulling force
thereon, a standoff arrangement (comprising standof~
studs~ connectable to a given end portion of the
first yoke member for exerting a pushing force
(opposite to the pulling force) thPreon, and an
operating mechanism (in the form of a piston-cylinder
combination) interposed between the pulling as~embly
and the standoff arrangement for operating on the
pulling assembly to cause it to exert the pulling
for~e, and for operatin~ on the standoff arrangement
to cause exertion of the pushing force, so that the
journal bearing mounted in the given end portion of
the first yoke member is forced out of that portion.
In accordance with a further feature of ~he
inven~ion, the piston of the operation arrangement is
movable within the cylinder thereo~ in response to
~he injection o~ fluid under high pressure (such as
grease from a high-pressure grease gun) into the
cylinder so as to urge the pulling assembly in a
dlrection away from the universal joint while the
~tandoff arrangement maintains a pushing force in a
direction toward the universal joint.
Pr~ferably, the first embodiment has a
headplate and sidebars which form the pulling
assembly while standoff studs form the standoff
arrangement, the s~andoff studs having threaded ends
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which are insertable in corresponding threaded holes
located in an end portion of the yoke member from
which the journal beari~gs are to be removed.
As a further preference, the operating
arrangement includes an aperture located in the wall
of the cylinder for receiving the nozzle o~ a grease
gun, from which grease at high pressure is injected
into the cylinder so as to provide moving force to
the piston contained therein.
A second embodiment of the invention
comprises a push-type tool for disassembling a
universal joint, the push-type tool comprising a
cylinder closed at one end remote from----the yoke
member from which the journal bearing is to be
removed, a piston movable within the cylinder along
its axis, and an injection mechanism located at a
point in the cylinder wall between the closed end and
the piston ~or receiving and injecting fluid under
high pressure into the cylinder so as to move the
piston toward the journal bearing, forcing the
bearing out of the far end of the yoke member.
Pre~erably, the push-type tool includes a
support arrangement having a flat surface on which
the cylinder is positioned, and contact fingers
extending from the flat surface toward the universal
joint so as to contact a ~irst yoke member, which is
perpendicular to a second yoke member from which the
journal bearing is ko be remov~d, at respective
points on either side of the first yoke member.
As a further preference, borsholes are
provided within the cylinder wall and parallel to the
cylindrical axis, and the yoke member from which ths
journal bearing is to be removed has threaded holes
provided in its near end ~that is, the end closest to
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the tool) along an axis parallel to the cylindrical
axis and in alignment with the boreholes ~o that
threaded cap screws can be inserted through the
boreholes and can be screwed into the threaded holes,
thus securing ~he tool to the universal joint for the
disa~sembly operation.
Furthermore, the pu~h-type tool i5
preferably provided with injection means in the form
of an aperture running through the wall of the
cylinder at a point betwsen the closed end thereof
and the piston for receiving the nozzle of a grease
gun, from which grease is injected under high
pressure to move the piston and force the journal
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bearing from the remote end of the yoke member (that
is, the end of the yoke member furthest from the
tool).
Advantages o~ the present invention are as
follows. ~oth embodiments of the invention comprise
a compact tool, highly portable in nature, for
disassembling the universal joint of the drive shaft
of a vehicle utilizing a technique involving the
injection of high-pressure fluid, ~uch as grease from
a grease gun~ into a cylinder so as to drive a piston
to create ei~ er a pulling force (via the use of a
headpla~e and sidebars) or a pushing force (via the
use of a support assembly) for ejecting a journal
bearing from an end portion of a yoke member of the
universal joint. Thus, the present invention
provides two embodiments of a universal joint
disassembly tool, both of which embodiments have the
advantage of portability usually associated with
manually driven tools, as well as the further
advantage of high-pressure operation usually
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as~ociated with large industrial-type pulling or
pushing apparatu~.
Furthermore, it should be noted that the
two embodiments of the universal joint disassembly
tool have several elements or components in common
(such as the pi5ton and cylinder), so that a
relatively small and highly portable tool kit can be
devised while prsviding the user with the advantages
of bo~h embodiments (both the pull-type and push-type
~ool~).
Therefore, it is a primary obiect of the
present inven~ion to provide tools for the
disassembly of a ~r~ve shaft universal joint of a
vehicle.
15It is an additional object of the present
inventi~n to provide tools for the disassembly of a
universal joint, wherein the tools operate in
response to the injection of fluid under high
pressure into the tool~
20It i~ an additional object of the pre~ent
invention to provide tools for the disassembly of a
univexsal joint, wherein the tools are composed of a
compact arrangement of elements resulting in a high
degree of portability.
25It is an additional object of the present
invention to provide tools for the disassembly of a
universal joint, wherein the tools comprise pull-type
tools which exert a pulling force on the universal
joint, while exerting a pushing force on an end
por~ion of that one of the yoke member~ of the
universal joint from which a journal bearing i~ to be
removed.
It is an additional object of the present
invention to provide too}s for the disassembly of a
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universal joint, wherein the tools comprise push-type
tools which exert a pushing forc~ on the universal
joint from which the journal bearing is to be
removed.
The above and other objecks that will
hereinafter appear, and the nature of the invention,
will be more clearly understood by reference to th~
following description, the appended claims, and th~
accompanying drawings.
Brief Description of Draw~nqs
FIGURE 1 is a perspective view of a first
embodiment of the present invention, comprising a
pull-type tool. -~ ~~~ ~~- ~ ~~--~-~~~~~~~~~~~ ~ ~
FIGURE 2 is a cross-sectional view of the
cylindar of the present invention, as seen along line
A-A' in FIGURE 1.
FIGURE 3 is a front view of ~he first
~mbodiment of the present invention, as ukilized
during a first step of disassembling a universal
joint.
FIGURE 4 is a ~ront view of the first
embodiment o~ the present invention, as utilized
during a second step of disassembling a universal
joint.
FIGURE 5 is a bot~om view of the headplate
shown in FIGURE 3.
FIGURE 6 i~ a perspective view of a second
embodiment of the invention, comprising a push-type
tool.
FIGURE 7 is a cross-sectional view of the
cylinder, as seen along ~ection line B-B' in FIGURE
6.
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Best Mode for Carryinq Out the Inventio~
The pre~ent invention will now be more
fully described with referencP to the various figures
of the drawings.
FIGURE 1 is a perspective view of a first
embodiment of the invention, comprising a pull-type
tool for disassembly of a universal joint. As seen
therein, the pull type tool 10 comprises a headplate
12, sidebars 14 and 16, a cylinder 18, a piston 20J a
filler plug 22a, and standoff ~tuds 28 and 30. As
also seen in FI~URE 1, sidebars 14 and 16 are
provided with grooves 36 at the top portions thereof,
the grooves 36 functioning to accommodate end
portions of the headplate 12, while the end portions
o~ the headplate 12 are provided with slots 37, into
which downwardly protruding portions 38 of the end
portions of the sidebars 14 and 16 are inserted when
as~embling the tool 10.
Sidebars 14 and 16 are further provided, at
their distal ends, with holes 24 and 26, the latter
being designed to accommodate cap screws (to be
discussed below~ on the universal joint. In
addition, standoff stud 28 and 30 are dimensioned so
as to be insertable into boreholes 34 provided in
opposing portions of the cylindrical wall of the
cylinder 18, while standoff s~uds 28 and 30 are
provided ak their other ends with threaded portions
28a and 30a, respectively, the latter being provided
. so that the standof~ s~uds 28 and 30 can be screwed
into respective boreholes ~to be discussed below) in
an end portion of the yoke member, from which the
journal bearing is to be remov d, in the universal
joint.
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FIGURE 2 is a cross-sectional view of the
cylinder 18 of FIGURE 1, taken along She section line
A-A' thereof. As seen in FIGURE 2, the innex
dimensions of the ¢ylinder 18 are such as to
accommodate a piston 20. An O-ring grease seal or
grease fitting 32 is positioned prior to inserting
the piston 20 into the cylinder 18. Cylinder 18 is
also provided with filler plugs 22a and 22b. As seen
in FIGURE 2, opposing portions of the cylindrical
wall of the cylinder 18 are provided with boreholes
34, into which standoff studs 28 and 30 can be
inserted.
FIGURE 3 lS a front view of the pull-type
tool 10 of FIGURE i, as assembled for operation in
the disassembly of the universal ~oint. As seen in
FIGURE 3, the universal joint 40 comprises a pair of
yoke members generally perpendicular to each other,
with the end portions of a first yoke member being
indicated by reference numerals 42 and 44. As is
well-known to those of sklll in the art, such
universal joints contain journal bearings tnot
shown), each journal bearing disposed adjacent to or
in a respective end portion (such as end portions 42
and 44) of the universal joint. The operation of
disassembling a universal joint, using the pull-type
tool 10, will now be described with reference to
FIGURE 3.
As a first step in such a disassembly
operation, the pull-type tool 10 is utilized to
remove the journal bearing (not shown) contained in
end portion 42 of the vertical yoke of universal
joint 40. The two standof~ studs 28 and 30 are
screwed into boreholes in the end portion 42 of the
yoke, and the cylinder 18 i8 slipped over the upper
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portions of the standoff studs 28 and 30 by inserting
those upper portions into the boreholes 34 contained
in the cylinder wall o~ cylinder 18.
With reference to FIGVRE 5, which is a
bottom view of the headplate 12, it is seen that
headplate 12 contains a rece~sed portion or shallow
bore 60 in its bottom face, ~o that the headplate 12
can be placed on top of the cylinder 18, it being
noted that the cylinder 18 is positioned with its
open end facing upward. A pull yoke assembly is now
formed by placing sidebars 14 and 16 in engagement
with the left and right end portion~ of the
horizontal yoke of universal joint 40,-as shown in
FIGURE 3. This is accomplished by slipping sidebars
14 and 16, and specifically the holes 24 and 26
(FIGURE 1) therein, over retaining cap screws 52 and
54, which are best seen in FIGURE 4. The upper
portions of sidebars 14 and 16 are then engaged with
the end portions of headplate 12, as previously
discussed above with reference to the grooves 36,
slots 37 and downwardly protruding portions 38 of
sidebars 14 and 16, as best seen in FI~URE 1.
Finally, the entire assembly is held together for
convenience in handling with an appropriately sized
o-ring 46.
The nozzle of a conventional grease gun is
placed on filler plug 22a or 22b, 80 that grease
pressure can be applied to the interlor of the
cylinder 18. This pressure causes the piston 20 to
rise inside of cylinder 18, exerting a li~ting force
on the headplate 12, and thus on the sidebars 14 and
16, as well as the horizontal yoke attached thereto.
This, in turn, causes a lifting force to be applied
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to the journal bearing contained within the upper
yoke collar 42.
In the meantime, standoff studs 28 and 30,
disposed between the cylinder 18 and the upper yoke
collar 42, exert a downward force on the upper yoke
collar 42. As a result, the journal bearing
contained in the upper yoke collar 42 slips out into
the space beneath the cylinder 18 and between the
standoff studs 28 and 30. Headplate 12, ~idebar6 14
and 16, cylinder 18 and studs 28 and 30 can be
removed, and the bearing is picked off. At this
point, the journal end o~ the universal joint cross
in the vertical yoke of-FIGURE 3 is exposed.
FIGURE 4 is a front view of the pull-type
tool, as utilized in a second step in the disassembly
process, that is, the step of removing the journal
bearing (not shown) contained in the lower yoke
collar 44 of universal joint 40. After the first
step is completed, power cylinder 18 is emptied by
taking out filler plug 22a or 22b (FIGURE 2) and
pushing the piston 20 back in the bore of cylinder
18. The filler plug 22a or 22b and piston 20 are
then reinstalled, and cylinder 18 is then placed,
with its open end downward, on the upper yoke collar
42, and is fastened thereto using cap screws 48 and
50. At this point, the piston 20 is contacting the
exposed journal end of the universal joint cross.
The nozzl~ of a conventional grease gun is
inserted into filler plug 22a or 22b, and grease
pressure is once again applied to the interior of
cylinder 18, causing piston 20 to move downward,
forcing the journal bearing in lower yoke collar 44
to be pushed out of its bore. At this point, with
both bearings removed, the universal joint cross,
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which is attached to the other yoke (the horizontal
yoke in the ~igure~), and that end of the drive
shaft, can now be taken off the drive pinion yoke.
For total disassembly of the universal
joint with the present in~ention, two conventional
hook adapters of appropriate f it can be placed over
the bare ends o~ the universal joint cross, the
latter being well-known to those of skill in the art,
and the arrangements of FIGURES 3 and 4 can be again
employed in a two-step process to remove journal
bearings from the end portions of the other yoke tthe
horizontal yoke).
FIGURE 6 is a perspective view of the
second embodiment o`f the present invention, and
specifically a perspective view of a push-type tool
~or disassembling the universal joint of the drive
shaft of a vehicle. As seen in FIGURE 6, the push-
type tool 70 comprises a cylinder 18 and associated
piston (not shown in FIGURE 6, but shown by reference
numeral 20 in FIGURE 7), a pair of cap screws 72 and
74, and a pushing assembly 80 having a ~lat surface
82 and pushing or contact ~ingers 84 and 86 extending
downward from the flat surface 82. As wa~ the case
in the previous figures, the wall of cylinder 18 is
provided with boreholes 76 and 78, through which cap
screws 72 and 74 are inserted. In additiont ~urther
holes 88 and 90 are provided in the flat surface 8~
of pushing assembly 80 to accommodate the portions of
cap screws 72 and 74 pro~ruding from the cylinder 18.
Furthermore, cap screws 72 and 74 are provided, at
their distal ends, with threaded portions 72a and
74a, such threaded portions being provided ~o that
cap screws 72 and 74 are able to be screwed into
corresponding threaded holes provided ln the upper
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yoke collar (such as upper yoke collar 42 of
universal joint 40 in FIGURE 3~, so as to ~asten the
entire assembly, comprising cyllnder 18 and pushing
assembly 80, to the universal joint.
FIGURE 7 is a cross-sectional view of the
cylinder 18f as taken along section line B-B' o~
FIGURE 6. Again, as was the case previously,
cylinder 18 is equipped with filler plugs 22a and
22b, and the interior bore of cylinder 18 i~ designed
to accommodate piston 20. Element 32 i6 an 0-ring
grease seal which stays on the piston 20.
In preparation for the disassembly
operation using -push--type -tool---70-, -the--cylind-er -1-8
and piston 20 are mounted on the flat surface 82 of
push~ng assembly 80, using cap screws 72 and 74
inserted through holes 76 and 78, respectively, in
the cylinder 18, and through holes 88 and 90,
respectively, in the pushing assembly 80. The entire
assembly is then placed over that yoke collar of the
universal joint opposite to the yoke collar which
co~tains the first journal bearing to be removed.
That is to say, re~erring back to the universal joint
40 shown in FIGURE 3, the push-type tool 70 would be
placed over upper yoke collar 42 so that the fingers
84 and 86 would contact the universal joint 40 at
points 8~a and 86a, respectively, in FIGURE 3 (that
is, at its cross). In addition, the piston 20 would
be in cylinder 18 which is indirectly connected to
upper yoke collar 42 via screws 72 and 74.
In operation, the nozzle of a conventional
grease gun is inserted onto filler plug 22a or 22b,
and grease pressure is applied to the interior of
cylinder 18, forcing piston 20 downward ~o as to
exert a pushing force, via pushing assembly 80
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(FIGURE 6), on the "cross" of the universal joint,
causing a reactive pulling force to be exerted, via
screws 72 and 74, on upper yoke collar 42 (FIGURE 3).
In this manner, the journal bearing contained in
lower yoke collar 44 is pushed out of the opposite
side of universal joint 40. The push-type tool 70 is
then removed fxom contact with the universal joint
40, and the journal end of the universal ~oint cro~s
is exposed.
Either filler plug 22a or 22b is removed
from the cylinder 18, the cylinder 18 i~ emptied by
pushing the piston back into its bore, and then the
filler plug 22a or 22b i~ reinstalled in cylinder 18.
As a second step, the journal bearing
contained in upper yoke collar 42 of universal joint
(FIGURE 3) can be removed by reassembling the
push-type tool 70, and fastening it to the lower yoke
collar 44 using cap screws 72 and 74 as previously
described. Grease pressure is then applied to the
interior of cylinder 18 through filler plug 22a or
22b, and the journal bearing in upper yoke collar 42
will be pushed out. The universal joint cross can
now be removed from the universal joint 40.
For a drive shaft disconnect, this is all
t~at would have to be done, as would be well
appreciated by those of skill in the art. However,
as will be equally appreciated, for a total univsrsal
joint disassembly, steps one and two outlined above
would be repeated for the le~t and right yoke collars
o~ the horizontal yoke of universal joint 40 as seen
in FIGURE 3.
It will be further recognized by those of
skill in the axt that, in accordance with the
operation of the push-type tool as just described
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above, if it is con6idered preferable, the ~irst step
could be repeated four times, once for each yoke
collar of each yoke member of the universal joint.
While preferred forms and arrangements have
been shown in illustrating the invention, it is to be
understood that various changes in detail and
arrangement may be made without departing from the
spirit and scope of this disclosure.
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