Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This invention relates to a manually adjustable wheel for
a high horse power vehicle such as an agricultural tractor.
It is known to provide agricultural tractors with manually
adjustable wheels whereby the track, i.e. the spacing
between the driven wheels of the tractor, may be adjusted
to suit its use in differing agricultural situations where
for example differing widths of rows of crops have to be
traversed by the tractor. Such known manually adjustable
wheels usually comprise a rim detachably secured to a disc
which is itself detachably secured in conventional manner
to a hub at the end of a drive sha~t. The means for de-
tachably securing the rim to the disc usually comprises a
plurality of lugs spaced apart circumferentially around
the radially inner surface of the rim.
The disc usually comprises a generally circular steel ele-
ment havingascalloped periphery, the apices of the scallops
providing circumferentially spaced apart portions of the
disc adjacent the rim which are bolted to the lugs.
It is an object of the invention to provide a manually ad-
justable wheel wherein the amount of material used in the
disc is optimized having regard to the required strength
of the wheel.
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According to the invention we provide a manually adjustable
wheel for a vehicle, e.g. a tractor comprising a rim to
receive a tire; a plurality of channel-shaped fixing lugs
spaced apart around the radially inner periphery of the
S rim, the lugs being arranged in pairs with the circumferen-
tial spacing between the lugs of each pair being less than
the circumferential spacing between adjacent lugs of adja-
cent pairs, the lugs having flanges which overlie, and are
welded to the rim thus fixedly to secure the lugs to the
rim; a disc of uniform thickness for connection to-a hub
of the vehicle; the disc having substantially the shape
of a square with the corners cut off so that the disc has
an irregular octagonal shape having four longer sides and
four shorter sides arranged alternately around the periphery
of the octagon, each shorter side being juxtaposed against
a pair of lugs; and bolt means detachably securing the
disc to the lugs, the disc and lugs being arranged so that
the disc may be selectively secured to the lugs in either
of two positions, the bolt means being located along the
shorter sides of the disc only and, at each of said shor-
ter sides comprising two bolts each passing through the
disc and through one of the lugs of a pair of lugs juxta-
posed to said shorter side.
The features of the invention will become apparent from the
following description given herein solely by way of example
with reference to the accompanying drawings wherein:
FIGURES 1 and 2 are axial viewsof manually adjustable wheels
constructed in accordance with the prior art;
FIGURE 3 is an axial view of a manually adjustable wheel
constructed in accordance with a first embodiment of the
invention;
FIGURE 4 is a cross-sectional view on the line 4-4 of
F igure 3;
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FIGURE 5 is an axial view of a manually adjustable wheel
constructed in accordance with a second embodiment of the
invention; and
FIGURE 6 is a cross-sectional view on the line 6-6 of
Figure 5.
Figures 1 and 2 of the drawings show manually adjustable
tractor wheels as constructed by prior art methods. Thus,
referring to Figure 1, it will be seen that the wheel rim
10 is provided on its radially inner surface with a set of
eight equi-distantly spaced apart lugs 12 welded to the
rim. The disc 14, which is detachably secured to the rim
lugs 12 by means of bolts 16, is of generally circular
configuration but has a scalloped periphery with the
apices of the scallops providing portions adjacent the rim
which are boltable to the lugs.
Figure 2 of the drawings shows a similar construction of
wheel wherein six circumferentially spaced lugs 112 are
provided on the rim 110 to which six corresponding por-
tions of a generally circular disc 114 are boltable.
In each case the variation in track is obtained by (1)
varying the surface of the disc which is in contact with
the hub and (2) varying the ends of the lugs against
which the disc abuts.
In each of the constructions shown in Figures 1 and 2 the
construction of the disc 14 is extremely wasteful of metal
since it is generally ~ircular and is usually produced as
a steel stamping out of a square or rectangular blank.
Referring now to Figures 3 and 4, these show a first em-
bodiment of the invention. There is a disc 50 secured to
a rim 51. The disc has a central planar portion or nave
52 and a conical portion 53 leading to a portion 54 which
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is perpendicular to thé rotary axis 55 of the wheel. The
disc is made from a square blank and as shown in Figure 3
is generally octagonal in shape having four longer sides
56 which alternate, around the periphery of the disc, with
shorter sides 57. It will be noted that the longer sides
56 are slightly concave towards the centre of the disc
while the shorter sides 57 are convex towards the centre
of the disc. It will be seen from Figure 4 that the disc
is of uniform thickness.
Secured to the radially inner periphery of the rim are
eight lugs 58 which are arranged in pairs with a circum-
ferential ~pacing between the lugs of each pair being less
than the circumferential spacing between adjacent lugs of
adjacent pairs. These lugs are generally of top hat sec-
tion and provide, referring to one of the lugs, a channelhaving sides 59, a base 60 and flanges 60a. The flanges
60a are welded to the rim and the channel in the lug ex-
tends generally parallel to the rotary axis of the wheel
and receives a bolt 61 which passes through the lug and
through an aperture 62 in the disc. Each bolt has a head
63 and is prevented ~rom turning by a rib 64 under the
head which fits in the channel of the lug as shown in
Figure 4, and carries a nut and washer 65 and 66 respec-
tively. It will be noted that the apertures 62 and the
bolts 61 are located on the shorter sides only of the disc.
Variation in track of a vehicle having wheels as shown in
Figures 3 and 4 is obtained either by reversing the disc
50 so that it diverges towards the left rather than the
right in Figure 4 and/or, by arranging the part 54 of the
disc at one side or the other of the lugs 58.
Referring now to Figures 5 and 6, these show a second em-
bodiment of thé invention comprising a disc 70 and a rim
71. As shown in Figure 5, the disc has been made from a
square blank and has four longer sides 72 and four shorter
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sides 73 so that it has the shape of an irregular octagon.
It will be noted that th longer sides 72 are slightly
concave towards the centre of the disc while the shorter
sides 73 are slightly convex relative to the centre of
the disc.
The rim is secured to the disc by lugs and bolts as before.
The lugs are indicated at 74, are arranged in pairs as
described in relation to Figures 3 and 4, and as shown in
Figure 6 are of top hot cross-section having a base 75,
side walls 76 and flanges 77. The flanges 77 are welded
to the rim so that the channels in the top hat section ex-
tend perpendicular to the rotary axis of the wheel. Each
lug is strengthened by a gusset plate 78.
Still referring to Figure 5, the disc 70 has a central
portion 79 adapted to be secured to the hub of a vehicle
via apertures 90 and bolts or studs (not shown). It then
has a portion 80 which is perpendicular to the rotary axis
of the wheel but displaced from the portion 79. Outwardly
of the portion 80 is a conical portion 81 which then leads
to a portion 82 perpendicular to the rotary axis of the
wheel. The portion 82 provides the shorter sides 73.
The disc is secured to the wheel by bolts 83 which have
squared portions 84 on their shanks to engage in square
section holes 85 in the walls 76 of a lug, each bolt having
a threaded portion 86 to receive a nut 87 and washer 88.
It will be noted that the bolts 83 pass through apertures
89 in the disc and that these apertures are located in the
shorter sides 73. Variation in track of a vehicle having
wheels as shown in Figures5 and 6 is obtained as before
either by reversing the position of the disc and/or by
changing the side wall of the lug against which the por-
tions 82 of the disc abut.
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It will be seen that the invention provides two embodiments
of wheeIs, specially for tractors, in which the discs can
be made from square blanks with very little waste in
material as compared with the considerable waste in
material involved where the blanks are circular as shown
in Figures 1 and 2 which relate to the prior art.
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