Note: Descriptions are shown in the official language in which they were submitted.
` 2177660
HUB IN8~r~T~T~TNG TOOL
~2~ g~ th~ Inv~ntion
1. Fi~ld of th~ Invontioll
This invention relates to hand tools and, more
5 particularly, to tools for installing hubs onto the ends of
shafts .
2. Descri~tio~ Qf th~ Prior Art
The installation of mechanical ~ -nts, such as
hubs or pulleys, upon shafts, such as automotive power
10 steering, water pump, alternator or other non-automotive
shafts, often requires special tools for producing the force
n~cl~#c:ry to push or press fit the ~ :)ne--Ls onto the
shaft. It is known to provide an end of such shafts with an
internally threaded bore.
A tool presently available to install a hub or
pulley onto a shaft includes a threaded screw for engaging
the threaded bore. Threaded on the other end of the screw
i5 a wrenching formation, such as a nut, adapted to be
gripped by a wrench. A bearing is pc~ n~ntly attached to
20 the nut and has a pushing face. The hub is installed onto
the shaft by aligning the hub on the end of the shaft and
inserting the screw through the bore of the hub and
threading the screw into the bore of the shaft. Rotation of
the wrenching formation then causes the pushing face of the
25 bearing to contact a face of the hub and move it onto the
shaft. The plane of the pushing face limits how far the hub
can be in6talled on the shaft. When the pushing face of the
bearing contacts the end of the shaft it can move axially no
further. At this point, the end of the 6haft and the face
30 of the hub are coplanar. Since the bearing is made from a
softer material than the 6haft, the pushing face tends to
become di6torted by the harder material shaft if continued
wrenching is attempted. This distortion causes hub
pl~c ~ accuracy to be lost. Further, repeated
35 bearing/shaft contact causes the destruction of the bearing.
Since the bearing is p~nr-n~ntly connected to the nut, the
` ~ 2 1 77660
majority of the tool is unrepairable and, therefore,
ef f ect ive ly destroyed .
~a~mary of the Invention
It is a general object of the invention to provide
an improved hub installing tool which avoids the
disadvantages of prior tools while affording additional
structural and operational advantages.
An important feature of the invention is the
provision of an apparatus for installing a hub onto the end
of a shaft which is of a relatively simple and economical
construction .
A still further feature of the invention is the
provision of an apparatus of the type set forth which
precisely limits the distance a hub can be installed onto a
shaft.
Yet another feature of the invention is the
provision of an apparatus of the type set forth which is
sturdy and resistant to deformation and which is easily
repairable .
These and other features of the invention are
attained by providing an apparatus and a method for
installing a hub onto a shaft having an outside diameter and
an axial threaded bore. The apparatus comprises a threaded
screw for threading into the bore, an installer nut threaded
onto the screw having an enlarged tool engaging end and a
reduced cylindrical extension having a distal end face and
an outside diameter and an annular bearing removably
mountable on the cylindrical extension in an installing
position, having a pushing face for contacting the hub and
an inside diameter slightly greater than the outside
diameter of the cylindrical extension and greater than the
outside diameter of the shaft, whereby the pushing face of
the bearing does not contact the shaft when the hub is
installed onto the shaft.
The invention consists of certain novel features
and a combination of parts hereinafter fully described,
` ~ 21 77660
illustrated in the a~:_ -nying drawings, and particularly
pointed out in the ~rpPn-lPd claims, it being understood that
various changes in the details may be made without departing
from the spirit, or 6acrificing any of the advantages of the
present invention.
Brief Description of the Dr~Win~s
For the purpose of facilitating an understanding
of the invention, there is illustrated in the accompanying
drawings a preferred embodiment thereof, from an inspection
of which, when considered in connection with the following
description, the invention, its construction and operation,
and many of its advantages should be readily understood and
appreciated .
FIG. 1 is a perspective view of the hub installing
tool of the present invention and a hub installed thereby
onto a fragmentarily illustrated shaft;
FIG. 2 is an exploded perspective view of the hub
installing tool, the hub and the shaft of FIG. l;
FIG. 3 is a sectional view taken generally along
the line 3-3 in FIG. l;
FIG. 4 is a view similar to FIG. 3 showing the
installing tool, hub and shaft at the beginning of
installation of the hub onto the shaft;
FIG. 5 is an enlarged view, similar to FIG. 3, of
another P~nho~ nt of the invention and showing a pulley
flange in partial section to which the hub is attached;
FIG. 6 is an exploded perspective view of an
alternative hub installing tool, and the hub and the shaft
of FIG. 1; and
FIG. 7 is a sectional view showing the installing
tool, hub and shaft of FIG. 6 after the hub has been
installed onto the shaft.
D~taileCI DesCriPtion of the Pr~f err~d Pn ho~ 9
Referring to FIGS. 1-4, there is illustrated a
shaft 10, such as a power steering shaft, having an
internally threaded bore 12 formed axially in one end
` 2177660
thereof. Referring particularly to FIGS. 1-3, a hub 14
having a central bore 16 has a tool contact face 18 and has
been installed by press fitting onto the shaft 10 by a hub
installing tool 20 in accordance with the present invention.
Though not illustrated in FIGS. 1-4, the hub 14 i5 typically
a member of a pulley and connected to a pulley flange (see
FIG. 5). The hub installing tool 20 includes a threaded
screw 22 which includes a tool engaging end 24, a central
threaded portion 26 and a smaller diameter threaded end
portion 28 which is threadedly engageable in the bore 12 of
the shaf t 10 .
The tool 20 further includes an annular bearing 30
having a central aperture 32. The bearing 30 includes a
pair of disc-shaped races 34 and 36 with a plurality of
balls 38 positioned therebetween and a generally cup-shaped
outer shell 40 enclosing the bearing races 34 and 36. The
outer shell 40 of the bearing 30 includes an annular planar
pushing face 42 which, as described in greater detail below,
is used to contact and push the hub 14 onto the shaft 10.
The tool 20 further includes an installer nut 46.
The installer nut 46 includes an enlarged tool-engaging end
48 and a cylindrical extension 50. As best seen in FIGS. 3-
4, the cylindrical extension 50 has a leading end face 51
and a circumferential groove 52 for receiving an O-ring 54.
The installer nut 46 also includes an internally threaded
bore 56 for threaded engagement with the central threaded
portion 26 of the screw 22.
Referring to FIGS. 1, 3 and 4, the tool 20 may be
assembled as follows: The O-ring 54 is placed over the
cylindrical extension 50 and into the circumferential groove
52. Next, the annular bearing 30 is placed over the
cylindrical extension 50 80 that the race 36 contacts a
radial shoulder 58 of the tool engaging end 48 of the
installer nut 46. The inner diameter of the race 36 is
slightly less than the outer diameter of the O-ring 54.
Thus, the bearing 30 is removably maintained in place by
` ~ 2177660
race 36 frictionally engaging O-ring 54. After the bearing
30 has been mounted on the installer nut 46, the nut 46 is
threaded onto the central threaded portion 26 of the screw
22 to completely assemble the tool.
The hub 14 i6 installed onto the shaft 10 by the
assembled hub installing tool 20 as follows: A portion of
the screw 22 is pa6sed, threaded end portion 28 first,
through the central bore 16 of the hub 14. The threaded end
portion 28 of the screw 22 is then threaded into the bore 12
of the shaft 10, by hand and/or by applying a wrench or
other tool to the tool-engaging end 24 of the screw 22.
Next, as best seen in FIG. 3, the hub 14 and its central
bore 16 are positioned against an outer end 60 of the shaft
10. It should be noted that the diameter of the bore 16 of
the hub 14 is slightly less than the outer diameter of the
shaft 10. The hub 14 must, therefore, be forcibly pushed
onto the shaft 10 and is maintained on the shaft 10 by a
press f it .
Once the hub 14 is initially positioned, the nut
46 is rotated until the pushing face 42 of the bearing
engages the hub 14. Thereupon, the installer nut 46 is
further rotated by use of a wrench to force the bearing 30
to move axially and push the hub 14 onto the shaft 10.
Rotation of the nut 46 continues, as seen in FIG. 3, until
the end face 51 of the cylindrical extension 50 contacts the
end 60 of the shaft 10, this contact preventing further
rotation of the nut 46.
In the embodiment shown in FIG. 3, the leading end
face 51 of the installer nut 46 of the assembled tool 20 is
substantially coplanar with the pushing face 42. This
permits the tool 20 to install the hub 14 onto the shaft 10
such that, as seen in FIG. 3, the tool contact face 18 of
the hub 14 is substantially coplanar with outer end 60 of
the shaft 10.
Alternatively, the length of the cylindrical
extension 50 can be varied to provide a tool capable of
21 77660
installing the hub 14 at different axial positions along the
shaft 10. For instance, the cylindrical exten6ion 50 can be
longer than the ' - -; r ~nt shown in FIGS . 1-4 60 that the
leading edge 51 of the extension 50 extends axially beyond
the plane of the pushing face 42. Since the leading end
face 51 of the cylindrical extension 50 will contact the
shaft 10 sooner, the hub 14 cannot be installed as far onto
the shaft 10 and its contact face 18 will be disposed
outboard of the outer end 60 of the shaft 10, after it has
been completely installed. Alternatively, if the length of
the cylindrical extension 50 is made shorter than the
pmholl; t shown in FIGS. 1-4, the leading end face 51 of
the extension 50 will be located axially inboard of the
pushing face 42. In this ~-~o'ir-nt, the leading end face
51 will contact the shaft 10 later and, therefore, the hub
14 can be installed a further distance onto the shaft 10,
such that the outer end 60 of the shaft 10 extends beyond
the plane of the contact face 18 after the hub 14 has been
completely installed onto the shaft 10.
2 0 As seen best in FIG . 3, the inner diameter of the
bearing 3 0 is pref erably larger than the outer diameter of
the shaft 10. This prevents the shaft 10 from contacting
the bearing 30 when the hub 14 is being installed. This
prevents overloading or deformation of the bearing 30, which
would or could occur if the bearing 30 would contact the
shaft 10 to prevent the hub 14 from being installed further
onto the shaft 10, since the outer shell 40 of bearing 30 is
typically formed of softer material than the shaft 10. This
prevention of bearing deformation allows the tool 20 to be
used longer without deformation or wear and thus allows more
accurate placement of the hub 14 onto the shaft 10.
Another advantage of the present invention is that
the tool 20 can easily be repaired if the bearing 30 does
become damaged by simply repairing or replacing the bearing
30. This advantage is achieved because the bearing 30 is
releasably retained on the cylindrical extension 50 by the
` ~ 2177660
O-ring 54. This type of mounting allows the bearing 30 to
be quickly and easily mounted onto or removed from the
extension 50 by manual ~res~,uLe: alone, without the use of
any other equipment. This allows easy access to the bearing
3 o, should it need to be repaired or replaced .
It should be noted that while the tool engaging
end 48 of the nut 46 and the tool engaging end 24 of the
screw 22 are illustrated in the figures as being hexagonal,
they may be shaped or configured in any conventional manner,
including being square or slotted.
It should also be noted that since the screw 22
has two threaded portions of different diameter, the tool 20
can therefore be used on two shafts having bores of
different diameter. As seen in FIG. 5, a shaft 10' having
an internally threaded bore 12 ' with a diameter greater than
the bore 12 shown in FIGS. 1-4 is illustrated. The tool 20
is used in the same way, described above, to install the hub
14 (which is 6hown, as described above, connected by any
conventional means to a pulley flange 70) onto shaft 10 '
except that the threads of the central threaded portion 26
of the screw 22, rather than the threads of the smaller
diameter end portion 28, engage the threads of the bore 12 ' .
Referring to FIGS. 6 and 7, wherein like numbers
represent like elements, an alternate tool 20' is provided
which is very similar to the tool 20, shown in FIGS. 1-5,
except that the installer nut 46 is replaced with an
alternative installer nut 46 ' and a washer 644 . Installer
nut 46 ' includes an enlarged tool engaging end 48 ' and a
cylindrical extension 50' having a circumferential groove
52' for receiving a pair of 0-rings 54'. The tool 20' may
be assembled as follows: Annular washer 644 is placed over
the cylindrical extension 50' and adjacent a radial lholllclF~r
58 ' of the tool engaging end 48 ' of the nut 46 ' . Next, the
O-rings 54 ' are placed over the cylindrical extension 50 '
and into the circumferential groove 52 ' . The annular
bearing 30 is then placed over the cylindrical extension 50 '
~ 2~ 77660
so that the race 36 of the bearing 30 contact6 the washer
644. The inner diameter of the race 36 is slightly less
than the outer diameter of the 0-rings 54 ' . Thu6, the
bearing 30 is removably maintained in place by 0-rings 54 ',
5 portion6 of which lie within the central aperture between
the races 34 and 36 of the bearing 30 and in the
circumferential groove 52 ' of the cylindrical extension 50 ' .
After the bearing 30 and washer 644 have been mounted on the
installer nut 46 ', the nut 46 ' is threaded onto the central
10 threaded portion 26 of the screw 22 to completely assemble
the tool 20 ' .
The tool 20 ' operates in the same manner as
earlier described tool 20, shown in FIGS. 1-5, except that
the installer nut 46 ' exerts pressure directly on washer
644, rather than directly on bearing 30, when the nut 46' is
rotated to push the hub 14 onto the shaft 10.
While particular Pmho(li nts of the present inven-
tion have been shown and described, it will be appreciated
by those skilled in the art that changes and modif ications
20 may be made without departing from the invention in its
broader aspects. Therefore, the aim in the ArpDnlled claims
is to cover all such changes and modifications as fall
within the true spirit and scope of the invention. The
matter set forth in the foregoing description and
25 A~ , nying drawings is offered by way of illustration only
and not as a limitation. The actual scope of the invention
is intended to be defined in the following claims when
viewed in their proper perspective based on the prior art.
