Note: Descriptions are shown in the official language in which they were submitted.
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CO~V~YOK R~T~G ASSEMBLY
This invention relates generally to a bearing
assembly for conveyors, such as conveyor rollers and idlers,
having a load-supporting roller tube positioned about a frame-
supported stationary shaft and wherein a bearing assembly is
interposed between the roller tube and shaft for rotation of
the tube relative to the shaft.
Bearing assemblies with which this invention is
concerned commonly include a housing having a periphery to
which an end of a roller tube is attached and a bearing which
is positioned between the shaft and the housing so as to
permit rotation of the housing about the shaft. An end cover
is positioned adjacent one side of the housing and is intended
to protect components of the bearing from dirt, water or other
undesirable cont~min~nts which may come into contact with the
bearing assembly. In order to reduce any likelihood that the
bearing assembly will come apart during use, it would be
desirable to provide a bearing assembly having components
which are joined in a manner which resists separation of the
components from one another.
Accordingly, it is an object of the present
invention to provide an improved bearing assembly of the
aforedescribed class which reduces the likelihood that the
bearing assembly will fail during use due to the separation of
assembly components from one another.
Another object of the present invention is to
provide such a bearing assembly which is uncomplicated in
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construction and can be assembled with relative ease.
Other objects and advantages of the invention will
become known from the following description and drawings in
which:
5FIGURE 1 is a perspective view of a typical con-
veyor belt support in which an embodiment of the present
invention is incorporated;
FIGURE 2 is a fragmentary cross-sectional view
taken along line 2-2 of FIGURE 1;
10FIGURE 3 is a view similar to that of FIGURE 2
illustrating the bearing assembly of FIGURE 2 in an exploded
condition;
FIGURE 4 is a fragmentary side elevational view of
the housing of the FIGURE 2 assembly as viewed along line
154-4 of FIGURE 3;
FIGURE 5 is a fragmentary cross-sectional view
taken along line 5-5 of FIGURE 4;
FIGURE 6 is a fragmentary side elevational view of
the end cap of the FIGURE 2 assembly as viewed along line
206-6 of FIGURE 3; and
FIGURE 7 is a fragmentary cross-sectional view
taken alo.lg line 7-7 of FIGURE 6.
Turning now to the drawings, and considering first
FIGURES 1 and 2, there is shown a conveyor idler, generally
25indicated as 20, including three load-supporting rollers 22
within which bearing assemblies 24 in accordance with the
present invention are positioned. Each roller 22 is rotata-
bly mounted upon a fixed shaft 26 which is, in turn, sup-
ported upon a rigid frame 27. ~he frame 27 is positionable
30upon a support and includes upright support posts 28 for
supporting each shaft 26 at its opposite ends. Each roller
22 further includes a hollow roller tube 30 arranged about a
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corresponding shaft 26 and extending the full length there-
of. Two bearing assemblies 24 are positioned on the shaft
26 at the opposite ends thereof permitting rotation of the
tube 30 relative to the shaft 26. The two bearing assem-
blies 24 positioned at opposite ends of the shaft 26 areidentical in construction so that the bearing assembly 24
positioned at one end 25 of the shaft 26 will be described.
With reference to FIGURES 2 and 3, the bearing
assembly 24 includes means defining a housing 36 to which
the roller tube 30 is swagged, an end cover 38 positioned
about the shaft 26 and a bearing 40 interposed between the
housing 36 and end cover 38 to accommodate rotation of the
housing 36 and roller tube 30 relative to the end cover 38
and shaft 26. As will be explained in greater detail, each
of the end cover 38 and housing 36 are joined to the bearing
40 in such a manner that the housing 36 and end cover 38
resist separation from the bearing 40 and thus resist sepa-
ration from one another.
The bearing 40 of the assembly 40 is a single-row
deep groove bearing of standardized construction having a
steel inner ring ball race 31, a steel outer ring ball race
33 and a plurality of steel balls 35 held between the inner
and outer races 31, 33 by a suitable retainer (not shown) so
that the outer race 33 is permitted to rotate relative to
and about the inner race 31. In the bearing 40 of the
depicted assembly 24, the inner race 31 has two opposite and
parallel sides 37, 39 arranged in radial planes of the
assembly 24 and a cylindrical inner (bore) surface 41, and
the outer race 33 has two opposite and parallel side faces
43, 45 arranged in radial planes of the assembly 24 and a
cylindrical outer surface 47.
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The housing 36 is preferably constructed of a hard
plastic material, such as a suitable Nylon R, and includes a
substantially cylindrical periphery 44 about which the inner
wall of the roller tube 30 is swagged and a central opening
48 arranged about the shaft 26 adjacent end 25, and a wall
portion 49 extending between the periphery 44 and opening
48. To facilitate the swagging of the tube 30 against the
housing periphery 44, a deep groove 42 is defined inwardly
of the periphery 44 and opening 48. The groove 42 accommo-
.. 10 dates an inward collapsing of the outer annulus of the
housing 36 as the tube 30 is swagged against the housing
periphery 44. For accurately positioning the bearing assem-
bly 24 within the tube 30 prior to the swagging operation,
the housing 36 includes an abutment flange 52 located to one
side of the periphery 44. As best shown in FIGURE 2, the
housing 36 is positioned within the tube 30 so that the
flange 52 abuts one end of the tube 30.
The wall portion 49 of the housing 36 includes an
inner side 66 arranged generally in a radial plane of the
housing 36 so as to span the region between the periphery 44
and central opening 48. In order to strengthen the wall
portion 49, a plurality of radially-extending webs 68 are
provided on the inner side 66.
With reference still to FIGURES 2 and 3, the
housing central opening 48 is provided by a body portion 50
of the housing 36 which tightly encircles the outer race 33
of the bearing 40 and which includes means for preventing
axial movement of the housing 36 relative to the outer race
33. In this connection, the body portion 50 includes a
recess 56 proportioned so that the bearing outer race 33 is
tightly received thereby, and so that an inwardly-directed
annular portion 58 is provided at the bottom of the recess
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56, or on the left side of the recess 56 as shown in FIGURES
2 and 3. The inwardly-directed annular portion 58 includes
a shoulder which provides a first abutment surface 60 which
is positioned in abutting relationship with one face 43 of
the bearing outer race 33, as shown in FIGURE 2.
In order to prevent axial movement of the housing
36 relative to the bearing outer race 33, the housing 36
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also includes a plurality of finger members 51 joined to the
housing body portion 50 for engaging the face 45 of the
bearing outer race 33 so that the bearing outer race 33 is
captured between the inwardly-directed annular portion 58
and the finger members 51. In this connection and as best
shown in FIGURE 5, each finger member 51 includes a major
portion 53 which extends substantially linearly from the
body portion 50 in a direction which is substantially paral-
lel to the rotational axis 62 (FIGURE 3) of the housing 36
about the end cover 38 and includes a tab 55 at the end of
the major portion 53 opposite the body portion 50. Each tab
55 includes a generally inwardly-directed surface 63 for
abutting the face 45 (FIGURE 3) of the bearing outer race
33. As best shown in FIGURE 5, each tab surface 63 is
shaped to accommodate the corner radius of the bearing outer
race 33. In the interests of this invention, the area of
the tab surfaces 53 which abut the bearing face 45 comprise
a second abutment surface which generally opposes and coop-
erates with the first abutment surface 60 to maintain the
bearing race 33 in position within the recess 56.
In the illustrated assembly 40, the housing 36
includes eight finger members 51 which are regularly spaced
about the central opening 48. In addition, the faces 43, 45
of the bearing outer race 33 are simultaneously engaged,
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respectively, by the first abutment surface 60 and the tab
surfaces 63 when the bearing 40 is positioned within the
recess 56. Accordingly, the distance as measured from the
first abutment surface 60 to the tab surfaces 63 corresponds
to the width of the outer race 33. Therefore, when posi-
tioned between the first abutment surface 60 and the tab
surfaces 63, the bearing 40 is tightly held therebetween and
prevented from moving axially relative to and through the
central opening 48.
~ 10 It is a feature of the assembly 24 that the finger
members 51 are adapted to resiliently flex radially outward-
ly relative to the housing body portion 50 from an unflexed
condition to accommodate the insertion of the bearing 40
into the central opening 48 during assembly and return to an
unflexed condition when the bearing 40 is positioned within
the central opening 40 so that its tab surfaces 63 are
positioned in abutting engagement with the face 45 of the
bearing outer race 33. To this end, each finger member 51
is relatively narrow in width, and the housing body portion
50 is formed with a groove 57 (FIGURE 3) which provides an
~ annular space 59 which encircles the finger members 51. In
the illustrated assembly 24, the groove 57 opens in the same
direction in which the finger member 51 extend from the
housing body portion 50. Thus, the flexibility of the
material, e.g. Nylon R, out of which the narrow finger
members 51 are constructed and the space 59 provided out-
board of the finger members 51 permits the finger members 51
to be forcibly flexed radially outwardly from an unflexed
condition as illustrated in solid lines in FIGURE 5 to a
flexed condition as illustrated in phantom in FIGURE 5. The
finger members 51 possess sufficient resiliency so that upon
removal of the force from the finger members 51 which ef-
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fected the flexure, the memory of the finger members 51
return the finger members 51 to the unflexed condition.
To facilitate the flexing of the finger members 51
outwardly as the bearing 40 is positioned within the housing
recess 56, each tab 55 includes an end surface 61 which is
sloped in the manner shown in FIGURE 5. When positioning
the bearing 40 within the recess 56, the bearing 40 is
aligned with the central opening 48 and arranged so that the
face 43 of its outer race 33 is positioned in engagement
with the tab sloped surfaces 61 and then forcibly moved into
the central opening 48 until the outer race face 43 abuts
the first abutment surface 60. As the bearing 40 is moved
into the central opening 48, the outer race 33 and tabs 55
act as cam and cam followers, respectively, in that the
peripheral outer surface 47 of the race 33 moves along the
sloped surfaces 61 in a manner forcing the tabs 55 radially
outwardly to the FIGURE 5 flexed condition. When the outer
race 33 engages the first abutment surface 60, the tabs 55
clear the bearing outer surface 47 and the memory of the
finger members 51 return the finger members 51 to the FIGURE
5 unflexed condition so that the tab surfaces 63 are posi-
tioned in abutting engagement with the face 45 of the outer
race 33.
To prevent the finger members 51 from flexing
radially outwardly when the bearing 40 is positioned within
the housing recess 56 to a condition at which the bearing 40
can be moved out of the recess 56, the bearing assembly 24
includes an insertable ring 65 positionable within the
groove 57 of the housing body portion 50. The ring 65 is
sized in such a relationship with the size of the groove 57
that the ring 65 is tightly held between the walls of the
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groove 57 when positioned therein. The ring 65 is prefera-
bly constructed of a hard plastic material, such as a suit-
able Nylon R, and as best shown in FIGURE 3 includes cylin-
drical inner and outer surfaces 67, 69, respectively, and
generally planar side faces 71, 73, respectively.
During assembly of the bearing assembly 24, the ring
65 is positioned within the groove 57 after the bearing 40
has been positioned within the housing recess 56 and the
finger members 51 return to their unflexed condition so that
the bearing outer race 33 is captured between the first
abutment surface 60 and the tab surfaces 63. The groove 57
is then in condition (e.g. unobstructed by the finger member
tabs 55) for receiving the ring 65 inserted facewise through
its opening until one of the ring faces 71 engages the
bottom of the groove 57. With the ring 65 thus received by
the groove 57, the finger members 51 are tightly encircled
by the ring 65 and prevented from flexing outwardly to the
FIGURE 5 flexed condition which may otherwise permit the
bearing 40 to shift axially relative housing 36 and out of
the recess 56. The bearing 40 therefore cannot be removed
from the housing 40 as long as the ring 65 is positioned
within the groove 57, and the ring 65 remains snugly re-
tained by the groove 57 during rotation of the housinq 36 so
that the bearing 40 cannot separate from the housing 36
during use of the assembly 24.
As shown in FIGURE 2, the ring 65 is sized so that
the side face 73 of the ring 65 protrudes out of the groove
57 when received thereby. In addition and as best shown in
FIGURE 3, the housing body 50 includes a rigid section 75
positioned between adjacent finger members 51 so as to
substantially fill the space therebetween. These rigid
sections 75 provide suitable inner surfaces for engaging the
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peripheral outer surface 47 of the bearing outer race 33 and
suitable outer surfaces for engaging the inner surface 67 of
the ring 65 when the bearing assembly 24 is assembled.
With reference again to FIGURE 2, the outer side
of the housing wall 49 and the ring 65 cooperate with the
end cover 38 so as to define a labyrinth passageway 88 which
permits relative rotation between the wall portion 49 and
end cover 38 and which inhibits the passage of dirt and
: other contaminants which may come into contact with the
bearing assembly 24 through the passageway 88. Such laby-
rinth passageways are common in bearing assemblies of this
class, and an example of another labyrinth is shown and
described in U.S. Patent 4,458,957. In the illustrated
embodiment 24 and as best shown in FIGURE 2, the housing
wall portion 49 defines on its outer side a pair of concen-
trically-arranged annular projections 70. These annular
projections 70 and the protruding side face 73 of the ring
65 are accepted by corresponding grooves defined in the end
cover 38 so that the surfaces of the annular projection 70
and the protruding side face 73 provide, in part, one side
,,,
of the passageway 88.
With reference to FIGURES 2-4, the end cover
38 includes a disc portion 82 positioned adjacent the outer
side of the wall 49 in which the annular projections 70 are
defined and a shaft-receiving hub portion 84 located cen-
trally of the disc portion 82. Like the housing 36, the end
cover 38 is constructed of a hard plastic material, such as
a Nylon R. The inner face of the disc portion 82 includes
annular tongues 86 which are received by grooves defined
between the housing projections 70 and protruding side face
73 of the ring 65 so as to interfit and form with the pro-
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jections 70 and ring side face 73 the labyrinth passageway88. As best shown in FIGURE 2, the labyrinth passageway 88
extends radially across the housing 36 from the central
opening 48 defined therein to an entryway, indicated as 89,
adjacent the housing periphery 44. The labyrinth passageway
88 provides a tortuous path along which dirt, liquids or
other undesirable contaminants must travel in order to reach
the bearing 40, and it is the provision of such a tortuous
path which inhibits movement of the contaminants to the
bearing 40 from the entryway 89. To further protect the
bearing 40 from contaminants, the inner face of the disc
portion 82 also includes an annular tongue 90 about which a
seal 92 is positioned and the hub portion 84 is enclosed at
one end by an end cap 94 positionable over so as to cover
the end 25 (FIGURE 2) of the shaft 26.
With reference to Figures 2 and 3, the hub portion
84 of the end cover 36 includes a body 100 which is tightly
received by the bore 41 of the bearing inner race 31 and
includes means for preventing axial movement of the end
cover 38 relative to the inner race 31. In this connection,
the hub portion body 100 is proportioned so that the bearing
inner race 31 is tightly positioned thereabout and so that a
shoulder portion 102 is provided along the outer surface of
the hub body 100 as shown in Figures 2 and 3. The shoulder
portion 102 provides an axially-facing abutment surface 104
which is positioned in abutting relationship with one face
39 of the bearing inner race 31, as shown as FIGURE 2.
In order to prevent axial movement of the end
cover 3d relative to the bearing inner race 31, the end
cover 38 also includes a plurality of finger members 106
joined to the end cover body 100 for engaging the face 37 of
the bearing inner race 31 so that the bearing inner race 31
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is captured between the abutment surface 104 of the shoulder
portion 102 and the finger members 106. In this connection
and as best shown in FIGURE 7, each finger member 106 in-
cludes a major portion 108 which extends substantially
linearly from the hub portion body 100 in a direction which
is substantially parallel to the rotational axis 62 (FIGURE
6) of the housing 36 about the end cover 38, and includes a
tab 112 at the end of the major portion 108 opposite the
body 100. Each tab 112 includes a generally outwardly-
directed surface 114 for abutting the face 37 of the bearing
inner race 31. As best shown in Fig. 7, each tab surface
114 is shaped to accommodate the corner radius of the bear-
ing inner race 31. In the interests of this invention, the
area of the tab surfaces 114 which abut the bearing face 37
comprise another abutment surface which generally opposes
and cooperates with the shoulder abutment surface 104 to
maintain the bearing race 31 in position about the hub body
portion 100.
In the illustrated assembly 24, the end cover 38
includes four finger members 106 which are regularly spaced
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about the shaft-receiving opening, indicated as 110, of the
hub portion 84. In addition, the faces 37, 39 of the bear-
ing inner race 31 are simultaneously engaged, respectively,
by the shoulder abutment surface 104 and the tab surfaces
114 when the bearing 40 is positioned about the hub portion
body 100. Accordingly, the distance as measured between the
shoulder abutment surface 104 to the tab surfaces 114 corre-
sponds to the width of the inner race 31. Therefore, when
positio~e~ between the shoulder abutment surface 104 and the
tab surfaces 114, the bearing 40 is tightly held therebe-
tween and prevented from moving axially relative to and
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along the length of the hub portion body 100.
It is a feature of the assembly 20 that the finger
members 106 are adapted to resiliently flex radially inward-
ly relative to the hub portion body 100 from an unflexed
condition to accommodate the placement of a bearing 40 upon
the hub portion body 100 during assembly and return to an
unflexed condition when the bearing is positioned upon the
hub portion body 100 so that its tab surfaces 114 are posi-
tioned in abutting engagement with the face 37 of the bear-
ing outer race 31. To this end, each finger member 106 is
relatively narrow in width and constructed of an appropriate
material, e.g., Nylon R, so that the finger members 106 may
be forcible flexed radially inwardly from an unflexed condi-
tion as illustrated in solid lines in Figure 7 to a flexed
condition as illustrated in phantom in Figure 7. The
finger members 106 possess sufficient resiliency so that
upon removal of the force from the finger members 106 which
effected the flexure, the memory of the finger members 106
return the finger members 106 to the unflexed condition.
To facilitate the flexing of the finger members
106 inwardly as the bearing 40 is positioned upon the hub
portion body 100, each tab 112 includes an end surface 118
which is sloped in the manner shown in Figure 7. When
positioning the bearing 40 about the hub portion body 100,
the bearing 40 is aligned with the shaft-receiving opening
110 and arranged so that the face 39 of its inner race 31 is
positioned in engagement with the tab sloped surfaces 118
and then forcibly moved over the hub portion body 100 until
the bearing face 39 abuts the shoulder abutment surface 104.
As the bearing 40 is moved onto the hub portion body 100,
the inner race 31 and the tabs 112 act as cam and cam fol-
lowers, respectively, so that the inner (bore) surface 41 of
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the race 31 moves along the sloped surfaces 118 in the
manner forcing the tabs 112 radially inwardly to the FIGURE
7 flexed condition. When the inner race 31 engages the
shoulder abutment surface 104, the tabs 112 clear the bear-
ing inner surface 41 and the memory of the finger members106 return the finger members 106 to the FIGURE 7 unflexed
condition so that the tab surfaces 114 are positioned in
abutting engagement with the face 39 of the inner race 31.
When the bearing assembly 24 is in its assembled
condition as illustrated in FIGURE 2, the tabs 51 of the
housing 36 and the tabs 106 of the end cover 38 engage
bearing faces 45 and 37, respectively, located on opposite
sides of the bearing 40. Consequently, when putting the
assembly 24 together, the bearing 40 is moved relative to
the housing body 50 into the recess 56 is a direction which
is opposite the direction in which the bearing 40 is moved
relative to and upon the hub portion body lO0.
As best shown in FIGURE 6, the hub portion body
100 includes a rigid section 120 positioned between adjacent
finger members 106 so as to substantially fill the space
therebetween. These rigid sections 120 provide suitable
outer surfaces for engaging the inner (bore) surface 41 of
the bearing inner race 31 and suitable outer surfaces for
engaging the outer surface of the shaft 26 when the shaft-
receiving opening 110 is positioned thereabout.
When the finger members 106 are in the FIGURE 7unflexed condition and as best viewed in FIGURE 6, the
shaft-receiving opening 110 possess a circular cross section
for snugly accepting the cylindrical surface of the shaft 26
when the shaft 26 is inserted endwise therein. However,
when the finger members 106 are moved inwardly to the FIGURE
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7 flexed condition, the tabs 112 of the finger members 106
are moved inwardly into the aforementioned cross section of
- the opening 110. Therefore, upon positioning the hub por-
tion body 100 about the shaft 26, the tabs 112 of the finger
members 106 are prevented by the surface of the shaft 26
from flexing inwardly to the FIGURE 7 flexed condition which
may otherwise permit the bearing 40 to shift axially rela-
tive to and off of the hub portion body 100. Therefore, the
bearing 40 cannot be removed from the hub portion body 100
as long as the assembly 24 remains positioned upon the shaft
26.
To enhance the protection of the bearing 40 from
dirt or other contaminants which may migrate toward the
bearing 40 along the labyrinth passageway 88 (FIGURE 2), a
seal 92, mentioned earlier, is positioned within the pas-
sageway 88 between the passageway entryway 89 and the bear-
ing 40. As best shown in FIGURE 3, the seal 92 is a V-ring
type of seal having a ring-like body 122 adapted to be
snugly positioned about the annular tongue 90 of the end
cover disc portion 82 and an annular lip 124 integrally
joined to the body 122. When the seal body 122 is posi-
tioned about the annular tongue 90 and the bearing assembly
24 is assembled as shown in FIGURE 2, the annular lip 124
engages the face 45 of the bearing outer race 33 so that the
passageway entryway 89 and inner componentry of the bearing
40 are separated by the seal 92. It follows that the seal
92 is positioned about the annular tongue 90 of the end
cover 38 before the bearing 40 is placed about the hub
portion body 100.
It is understood from the foregoing that the
aforedescribed embodiment 24 accomplishes the intended
purpose~ and objects of the invention. More specifically, a
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bearing assembly 24 is described having a housing 36 and end
cover 38 which each include a plurality of finger members 51
or 106 for positioning in a snap-fit relationship with the
outer race 33 or inner race 31 of a bearing 40. The housing
36 and end cover 38 also include appropriate abutment sur-
faces 60 or 104, and the finger members 51 or 106 include
tab surfaces 63 or 114 which generally oppose a correspond-
ing one of the abutment surfaces 60 or 104. When the bear-
ing 40 is positioned between the abutment surface 60 and tab
surfaces 63, the bearing outer race 33 is captured by the
housing 36. A ring 65 positioned about the housing finger
members 51 prevents the bearing 40 from separating from the
housing 36. When the bearing 40 is positioned between the
abutment surface 104 and the tab surfaces 114, the bearing
inner ring 31 is captured by the end cover 38. When the end
cover 38 is positioned about the shaft 26, the shaft surface
prevents the bearing 40 from separating from the end cover
38. Consequently, when the bearing assembly 24 is in use
about the shaft 26, the housing 36, bearing 40 and end cover
38 are prevented from separating from one another.
It will be understood that numerous modifications
and substitutions can be had to the aforedescribed embodi-
ment 24 without departing from the spirit of the invention.
Accordingly, the aforedescribed embodiment 24 is intended
for the purpose of illustration and not as limitation.
