Note: Descriptions are shown in the official language in which they were submitted.
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Rolling Bearing
The invention relates to a roller bearing according to the preamble of claim
1.
Roller bearings of this type or cages for such roller bearings are known for
example from DT-C3-14 00 324, DE-A1-31 34 241, DE-C2-34 24 741, DE-A1-
44 42 269, DE-Al-196 I9 712, DE-Al-196 54 584, EP-BI-O 225 508 and EP-
A1-O 392 146-
In the case of these known roller or rolling bearings, the u~bs of the cages
hav a
a considerable width so that only a small number of rollers can be
accommodated in the bearing and hence the loading capacity of the roller
bearing is relatively small.
The object of the invention consists in producing a roller bearing of the type
mentioned initially in which the packing density of the rollers is high and
which is easy to assemble.
This object is achieved according to t:he invention with the features of claim
1.
It is detected that the invention has been realised in the event that a
bearing
comprises substantially three different pasts and a multiplicity of rollers.
The
rollers are located between an outer and an inner ring and are separated by
the
cage. The peculiarity of the cage resides in the fact that it comprises two
cage
rings with different diameters and webs, which generally have a wedge-shaped
configuration and ensure that the rollers are disposed at a m; n i m a1
spacing
from each other. Generally, annular recesses or flanges are provided in the
inner and/or outer ring and ensure a preferably form-locking accommodation
of the cage internally of the rings. As a result, it is ensured at the same
time
that the cage can be introduced between the two rings in an axial direction
but
cannot be led right through said rings.
Thus, the packing density of the rollers ca.n. be made greater than in the
case of
lmown roller bearings so that greater forces can be transferred. The assembly
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of the roller bearing can be undertaken simply such that the inner ring of the
roller bearing, which is slid onto an engine shaft, is fitted with rollers
from an.
annular magazine, the rollers being maintained by lubricating grease.
Afterwards, the shaft is introduced with the inner ring and the rollers into
the
outer ring, which is fitted with the cage. The cage can be fixed to the outer
ring
in any manner and the wedge-shaped webs can be disposed betwzen the
rollers. Because of the small contact faces which the rollers have with the
wedge-shaped lateral face pieces of the cage, friction between the rollers and
the cage is minimised.
The run~~g faces, in which the roller bearings are guided, can of course also
be conftgured in the outer ring itself, i.e. not on the inner ring so that the
cage
is correspondingly changed and mounted on the inner ring.
The different embodiments of the invention thus have in common that the cage
serves for separation of the generally cylindrical roller bodies, is mounted
in the
outer or inner ring of the bearing and can be introduced in an axial direction
of
the bearing.
Farther useful and advantageous embodiments of the invention emerge from
the sub-claims.
A particularly useful embodiment of the invention provides that the outer and
the inner diameters of the cage rings are adapted to the inner or outer
diameters of the rings whilst taking account of the outer diameters of the
rollers. It is ensured by these measures that the cage rings, which generally
have different diameters, can be introduced between the cage rings but cannot
be led right through the roller bearing.
A further useful embodiment of the invention provides that the ring flanges
axe
orientated towards the axes of the rollers. It is ensured by these measures
that
the rollers are guided either by one or the other cage ring or by both
together.
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Furthermore, a useful embodiment of the invention provides that the webs are
configured as projections which preferably have a substantially trapezoidal or
triangular cross section_ It is useful within the scope of this inventive idea
if
the webs have wedge-shaped lateral face pieces. As a result, stability of the
cage is ensured, on the one hand, and, on the other hand, also that the
spacing between two adjacent rollers respectively can be kept to a minimum.
According to a further embodiment of the invention, the width of the webs in
the region of the wedge-shaped lateral face pieces is chosen such that the
spacing of the rollers from each other is only the minimum which still permits
lubrication of the bearings. Hence, the packing density of the rollers can be
configured optimally, which results in good force transference internally of
the
bearing.
Preferably, the spacing of the rollers is only a few tenths of a millimetre,
according to a further embodiment.
It so happens in a further embodiment of the invention that the outer ring has
a lateral, annular recess into which the cage ring, which has the greater
inner
diameter, is fitted in a form-locking manner. A roller bearing of this type is
particularly suitable as a double bearing in which the sides of two outer
rings,
which sides are provided with the recesses, contact each other. The fitting
can
preferably also be a force fit.
The advantages achieved by the invention consist particularly in the fact that
the proposed bearing can be used not only with a centric arrangement of shafts
and components but also with an eccentric arrangement. In the case of an
eccentric arrangement, additional forces occur as a result of which both the
bearing itself and the cage can be especially stressed. In the kno~crn case,
the
cage is guided radially on the rollers and consequently is excessively loaded
by
the rollers in the case of an eccentric arrangement. On the other hand, the
cage can be guided according to the invention on the outer ring and/ or on the
inner ring, as a result of which the cage can be used advantageously,
particularly with an eccentric arrangement of components. Consequently, the
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cage is not particularly subjected to additional forces of the roller bearing.
The
construction of the cage does not need to be especially robust. At the same
time, a particularly advantageous assembly of the cage is possible.
Finally, it is significant that the cage according to the invention permits an
especially small width of the roller bearing because the cage rings can have a
narrow cross section. At the same time, the cage rings can be sufficiently
high
because there is adequate space for their cross section height in the radial
direction. The most important object of the cage consists in separation of the
rollers, a uniform distribution of the rollers being assured at the same time
on
the circumference of their running path. The cage is generally made of plastic
material and can be produced by injection moulding.
The ixwentioa is now explained in greater detail with reference to
embodiments,
given by way of example, which show:
Fig. 1 an exploded perspective illustration of a roller bearing,
Fig. 2 a radial section through the assembled roller bearing according to Fig.
1,
Fig. 3 another radial section through the assembled roller bearing according
to Fig.~l,
Fig.3a the roller bearing according to Fig, 3, but without the cage,
Fig. 4 an axiai. plan view of the cage illustrated in Fig. 1, with a
peripheral
partial section VI,
Fig. S a section through the cage along the line V-V in Fig. 4,
Fig. 6 an enlargement of the partiai section VI in Fig. 4,
Fig. 7 an enlargement of the detail VII in Fig. 8,
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Fig. 8 a reduced, perspective view of the cage illustrated in Fig. 4,
Fig. 9 a radial section through the assembled roller bearing according to a
second embodiment,
Fig. 10 another radial section through the assembled roller bearing according
to a second embodiment,
Fig. l0a the roller bearing according to Fig. 10, but without the cage,
Fig. 11 an axial plan view of the cage illustrated in Fig. 9, with a
peripheral
partial section XIII,
Fig. 12 a section through the cage along the line XIL-XB according to Fig. 11,
Fig. I3 an enlargement of the partial section XIa in Fig. 11,
Fig. 14 an enlargement of the detail XIV in Fig. 15,
Fig. 15 a reduced, perspective view of the cage illustrated in Fig. 9,
Fig. 16 a radial section through the assembled roller bearing according to a
third embodiment,
Fig. 17 another radial section through the assembled roller bearing according
to a third embodiment,
Fig. 17a the roller bearing according to Fig. 17, but without the cage,
Fig. 18 an axial plan view of the cage illustrated in Fig. 17, with a
peripheral
partial section XX, .
Fig. 19 a section through the cage along the line XIX-~ according to Fig. 18,
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Fig. 20 an enlar ement of the partial section XX in Fig. 18,
Fig. 21 an enlargement of the detail XXT according to Fig. 22,
Fig. 22 a reduced, perspective view of the cage illustrated in Fig_ 16,
Fig. 23 a radial section through the assembled roller bearing according to a
fourth embodiment,
Fig. 24 another radial section through the assembled roller bearing accordizzg
to a fourth embodiment,
Fig. 24a the roller bearing according to Fig. 24, but without the cage,
Fig. 25 an axial plan view of the cage illustrated in Fig. 23, with a
peripheral
partial section XXVIZ,
Fig. 26 a section through the cage along the line XXVI-XXVI according to Fig.
25,
Fig. 2? an enlat-gement of the partial section ~CXVB according to Fig. 25,
Fig. 28 an enlargement of the detail XXVaI according to Fig. 29, and
Fig. 29 a reduced, perspective view of the cabe illustrated in Fib. 23.
The roller bearing in Fig_ 1 comprises an inner ring 10, a set of cylindrical
rollers 12, a cage 100 and an outer ring 30 and is mounted rotatably about the
axis 40a.
The inner ring 10 is provided on its axial ends with an annular flange lOb or
lOc respectively which delimit a running face l0a for the rollers 12. Because
of
the annular flanges lOb, lOc, the rollers are safeguarded against axial.
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displacement. The spacing A of the rollers 12 from each other when inserted in
the inner ring 10 is preferably approx. 0.1 mm. 'The rollers 12 can be
inserted
for example from a not-shown, annular magazine into the inner ring 10 by
means of lubricating grease. The axial length of the rollers 12 corresponds
approximately to the spacing of the annular flanges lOb and lOc from each
other.
The cage 100 has a front cage ring 102, a rear cage ring 101 and a number of
webs 104, which number corresponds to the number of rollers 12, which webs
extend transversely between the cage rings I01, I02 and are distributed
uniformly on the circumference of the cage 100. The webs 104 are configured
in a wedge-shaped cross section, a trapezoidal one here, as Figs. 4 and 6 show
in particular. In general, the webs are configured such that they taper
towards
the axes 12c of the rollers 12. The webs 104 have, as is shown most clearly in
Fig. 7, wedge-shaped lateral face pieces 104a and 104b, which are configured
at the ends of said webs respectively as projections, and opposite to which
pieces (104a and 104b) central wedge-shaped lateral face pieces 104c are
offset
towards the interior. The wedge-shaped lateral face pieces 104a, 104b serve to
guide the rollers 12, while the wedge-shaped lateral face pieces 104c are not
in
contact with the rollers 12. The contact faces of the webs 104 with the
rollers
12 are therefore very small_ The rollers 12 are rotatable about their axes 12c
and provided with cylindrical ru.n~ing faces 12a_ The axial end-side 12b of
the
rollers 12 is in contact with the face lOlb. The front cage ring 102 has a
larger
inner diameter dl (Fig. 3) than the inner diameter d2 of the outer zing 30
while
the rear cage ring 101 has a smaller outer diameter d3 than the inner diameter
d2 of the outer ring 30. Consequently, the cage 100 can, on the one hand, be
pushed over the rollers 12 or vice versa the rollers 12 can be pushed into the
cage 100 and, on the other hand, the cage 100 can be pushed into the outer
ring 30, during assembly of the roller bearing. When- the roller bearing is
mounted, the rear end-side 12b of each roller 12 abuts against the inner face
lOlb of the cage ring 101 (Fig. 3).
In the front lateral wall of the outer ring 30 there is provided an annular
recess
30' with a diameter d4 by means of which a vertical receiving face 30'a and a
l
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horizontal receiving face 30'b are formed, and the radial inner side defines a
further running face 31 for the rollers 12 (Fig. 2, 3a). The front cage ring
102 is
fitted into this recess 30' such that the inner face 102a of said cage ring is
situated opposite the vertical outer face 30'a while the edge face 102b of the
cage ring 102 is situated opposite the horizontal receiving face 30'b. The
outer
face 102c of the cage ring 102 thereby terminates flush with the front lateral
face of the outer ring 30 or, with respect to the latter, is offset towards
the
interior. The arrangement of the cage 100 on the outer ring can be effected in
any manner. However, the arrangement is effected preferably by receiving of
the front cage ring 102 in the recess 30' in which said arrangement is mounted
with clearance and in a floating manner.
It also emerges from Fig. 2 that the outer face 104d of each strut 104 is
offset
towards the interior relative to the edge face lOla of the rear cage ring 101
so
that a larger gap 29 is formed between the ninn~ng face 31 of the outer ring
30
and the outer face of the strut 104d. This gap ensures better passage of the
lubricating grease. The cage 100, illustrated in Figs. 4, 5 and 8, vcrith the
cage
rings 101, 102 has the measurements dl and d5 or d3 in the radial direction.
The larger cage ring 102 has two radially orientated faces 102a and 102c and
an axially orientated face 102b while the smaller cage ring 101 is provided
with
faces lOla, lOlc and lOlb (cf. Fig. 3). There applies thereby: d3 s d2 5 dl
and
d5 s d4.
The dimensions here are chosen such that the cage in the confnes of its radial
clearance does not "fall" onto the rollers, otherwise the result could be
radial
guidance of the cage on the rollers, which is undesirable. Rather, the cage is
guided via its radial faces lOla and 102b on the faces 30'b and 31.
A second embodiment of the invention is illustrated in Figs. 9 to 15, the
parts
which have the same function as the parts according to Figs. 1 to 8 being
provided with the index "1". The peculiarity of the embodiment consists in the
fact that the »ner ring 10.1 has only one annular flange lOb.l, the outer ring
30.1 has an annular flange 30".1 and the .age 100_ 1 is configured such that
it
can be disposed between the two x~ngs for operation.
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The peculiarities of the cage 100.1 consist in the fact that its rear cage
ring
100.1 is offset in steps, its face lOla.1 and lOlb.l co-operating with the
flange
30".1. The rollers 12 are guided between the annular flanges lOb.I and 30".1.
There applies thereby d3 s d6 s d 1 s d2 s d5 s d4.
A third embodiment of the invention is illustrated in Figs. 16 to 22, the
parts
which have the same function as the parts according to Figs. 1 to 8 being
provided with the index "2".
the third embodiment of the invent~.on illustrated in Figs. 16 to 22 has the
peculiarity that the outer ring 30.2 is provided with two a~ular flanges 30'.2
and 30".2, while the inner ring 10.2 has, on the one hand, no annular flange
and, on the other hand, an annular recess 10'.2. The cage 100.2 is also
configured correspondingly, its webs tapering front the central axis 40a
outwardly. This embodiment of the invention differs therefore from the first
embodiment according to Fig. 1 in that the outer ring 30.2 has the annular
flanges 30'.2, 30".2 and the recess 10'.2 is configured in the inner ring
10.2.
There applies therefore a certain kinematic reversal of specific functional
parts.
There applies thereby d4 s d5 s dl s d2 s d3.
The cage 100.2 is thus configured as an "external toothed wheel", while the
cage 100 according to Fig. 8 is configured as an "internal toothed wheel".
A fourth embodiment of the invention is illustrated in Figs. 23 to 29, the
parts
which have the same function as the parts according to Figs. 1 to 8 being
provided with the index "3".
The fourth embodiment of the invention illustrated in Figs. 23 to 29 has the
peculiarity that the outer ring 30.3 has only one flange 30'.3 while the inner
ring 10.3 has, however, an annular recess 10'.3 and an annulax flange lOc.3.
The cage 100.3 is adapted correspondingly. There applies thereby d4 s d5 s dl
sd25d6sd3.
