Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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STEERING ~ IEEL MOUNTIN(~J
1 An object of my invention is to improve the mount-
ing oE a steering wheel of a material susceptible to being
expanded or fractured by a wedging action imparted to the hub by
a shaft inserted in the hub in such a manner as to resist such
expansion or fracturing.
Another object is to provide a reinforcement to the
hub of a wheel at a location where the hub is subjected to a
wedging action by the hub being mounted on the upper end por-
tion o~ a steering shaft of a vehicle.
Another object is the improvement of a non-rotational
interlock between a molded resin steering wheel and shaft by
a metal washer embedded in the wheel positioned to provide a
metal-to-metal engagement with the shaft.
Another object is the provision of a reinforcing metal
washer embedded in the hub of a molded plastic wheel for improv-
ing both the strength of the wheel hub accommodating the steer-
ing shaft of a vehicle and for improving the non-rotational
interlock between the wheel and the shaft.
Other objects and a fuller understanding of this
invention may be had by referring to the following description
and claimsl taken in conjunction with the accompanying drawings
in which:
Figure 1 is a plan view of a steer:Lng wheel mounted
on a vehicle steering shaft in accordance with my invention;
Figure 2 is a cross-seckional view of the mounting
arrangement shown in Figure 1 and taken along the line of 2-2
of Figure l;
Figure 3 is a sectional view, enlarged from the
scale shown in Figures 1 and 2, taken in a plane coinciding
with the axis of the wheel and shaft, showing the detail of
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1 the mounting of the wheel on the shaft, only the portion of the
wheel at the hub being shown;
Figure 4 is a view, on the scale of Figure 3, look-
ing up at the bottom side of the wheel in the region of the
hub prior to the mounting of the wheel on a shaft;
Figure 5 is a side view of a steering shaft utilized
in my mounting, oin the same scale as Figures 3 and 4, and
turned on its axis to show both of two opposite flat sides
tapered toward the upper end portion of the shaft; and ~.
Figure 6 is a view of the shaft similar to the ~iew
of Figure 5, but in which the shaft has been rotated 90 on
its a~is to show but one o~ its two opposite flat sides.
The mounting i5 particularly adapted for the mounting
of a steering wheel to the upper end portion of a steering
shaft of a vehicle, such as a tractor, riding lawn mower, and
the like, whereby turning of the wheel rotates the shaft on
its axis for steering the vehicle. The wheel in common practice
is made of a molded plastic resin such as polypropylene or
other sturdy readily lded plastic.
The steering shaft is metal such as steel and adapted
to steer a vehicle upon rotation of the shaft by the turning :;
of a wheel interlocked with the shaft.
In the drawing, the wheel is generally designated
by the reference character 11. The steering shaft upon which
the wheel is mounted is generally designated by the reference
character 12.
The wheel 11 has a rim 13 carried in the usual manner
on the outer ends of spokes 14 radiating from a hub 15. Extend-
ing around, and spaced from, the hub 15 is a skirt 16. An
upper wall 17 near the upper side of the hub extends across
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1 between the hub 15 and skirt 16. A round hole 17A extends
through the wall 17 at the axis of the hub 15.
Above the wall 17 is a dwell 18. This dwell 18 is
closable by a disk 20, seen in Figure 2, inserted in the dwell
to hide the contents thereof and for improvemen-t of the appear-
ance.
Extending between the hub 15 and the sklrt 16 below
the upper wall 17 are three equidistantly spaced bracing walls
26. Depending down from each of these walls 26 is a spacing
lug 27 utilized in the positioning of the wheel.
The hub 15 has a central opening extending axially
thereof from the lower side of the hub, as seen in Figures 2
and 3, to the round hole 17A in wall 17. This central opening
has two opposed flat walls and alternately with these opposed
flat walls are two opposed round walls.
As seen in Figure 3, the two opposed flat walls are
tapered, that is they are gradually inclined toward each other
as they extend upwardly toward the upper side of the hub. The
said central opening in the hub is in axial alignment with,
and cornmunicates with the round hole 17A. The opposed round
walls of the said central opening generally coincide with a
phantom cylindrical form axially disposed of the hub.
The shaft 12 has a main body 21 of cylindrical or
rod-like configuration adapted to be connected by suitable
lin~cage, not shown, with the steering mechanism of ~ vehicle.
The shaft 12, by a forging operation, is enlarged at a loca-
tion above the body 21 to form the shoulder portion 22 as better
illustrated in Figures 5 and 6.
Above the shoulder portion 22 the shaft 12 is forged
or otherwise formed to provide the upper end portion of the
1 shaft. This upper end portion has two oppositely disposed
flat sides 23 and two oppositely disposed round sides 24
which are alternately disposed relative to the flat sides
around the circumferential extent of the upper end portion
of the shaft.
As better seen in Figures 2, 3 and 5, the two opposed
flat sides 23 are tapered in that they are progressively
inclined toward each other as they extend upwardly from the
shoulder portion 22 toward the upper free end of the shaft 12.
The round sides 24 of the shaft end portion generally coincide
with a phantom cylindrical form axially disposed of the shaft.
At the upper free end of the shaft in cylindrical
form it is threaded to provide the threaded round end 25. A
nut 28 is threadably engaged to the threaded end portion 25
after the shaft is mounted with the hub, as shown in Figures 1,
2 and 3. A cup--shaped spring washer 29 is positioned between
the nut 28 and top wall 17 of the wheel to hold the nut
tightly in position.
Embedded in the plastic material of the hub 15 at
the entrance to the central opening therein at the lower
side of the hub is a cup-shaped washer 19 of metal, preferably
of steel. I'his washer 19 has side walls l9A disposed in a
cJeneral cylindrical form upwardly from the flat intermediate
portion of the washer. These side walls l9A extend sub-
stantially parallel to the axis of the hub at a location dis-
posed radially outward from the wall~ of the central opening
in the hub and radially inward from the outer walls of the
hub 15, as better seen in Figure 3. The base or intermediate
portion of the washer is disposed flush with the bottom side
of the hub lS. As seen in Figures 2 and 3, the bottom surface
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1 of this base or lntermedlate portion of the washer 19 is dis-
posed in the same horizontal plane as the bottom surface of the
hub 15 at its lower side. The washer 19 is embedded in the
plastic during the molding of the wheel and becomes part of
the wheel.
By reason of the tapered opposed flat sides 23 of the
tapered end portion of the shaft keyed to the tapered opposed
flat walls of the said central opening in the hub when the
parts are in the position illustrated in Figures 2 and 3, the
wheel and shaft are interlocked so that the shaft is rotated
on its axis by the turning of the wheel on its axis.
Also by reason of the tapered disposition of the
flat sides 23 of the shaft end portion which engage the flat
walls of the central opening of the hub when the shaft end
portion is moved upwardly into the central opening, there is
a wedging action by the flat sides 23 pressing against the flat
walls. This wedging action is particularly present when the
taper of the flat walls of the central opening do not exactly
coincide with the taper of the flat sides 23 of the shaft end
portion throughout the length of the taper. In the absence of
complete 100~ coincidence of the taper of the side walls of
the central opening in the hub with the taper of the flat sides
23 of the shaft end portion such wedging action can be signifi-
cant.
The wedging action that may result, and often does
not result in the absence of such precise coi.ncidence of the
engaging tapered surfaces, may be sufficient to expand to the
point of fracturing the hub 15 and particularly at the lower
side of the hub adjacent to the entrance to the central open-
ing. Such expansion and resulting fracture produce a poor
1 mounting of the wheel on the shaEt, a looseness, and a mis-
alignment or wobbling of the wheel relative to the shaft.
The washer 19 embedded in the hub as described rein-
forces the hub at the entrance to the central opening and resists
such radially outward force imparted to the hub by the des-
cribed wedging action. The expansion of the hub that could
otherwise occur by the wedaing action is limited and the
fracturing to a great degree is generally eliminated by this
reinforcing action of the washer 19 at the location where needed
most.
The washer 19 has a central hole therein, this central
hole being defined by two oppositely disposed curved edges l9B
and two oppositely disposed straight edges l9C which are al~
ternately disposed relative to the curved edges l9B. The
curved edges l9B complement and are disposed outwardly of the
cylindrical walls 24 of the shaft end portion in the same
horizontal plane~ The straight edges l9C complement and are
disposed outwardly of the flat sides 23 of the shaft end por-
tion in the same horizontal plane.
In this manner the washer 19 is keyed to the shaft
end portion, and the washer 19 thus assists in keying of the
hub and shaft together. Turning of the wheel is assisted by
the washer keyed to the shaft in the rotation of the shaft by
turning of the wheel. In this way the washer 19 not only acts
to reinforce the hub against expansion but also assists in
the keying of the wheel and shaft together.
While I have illustrated and described a ~referred
embodiment of my invention, it will be understood that this
embodiment is by way of example only and not to be construed
as limiting.