Note: Descriptions are shown in the official language in which they were submitted.
10~4S46
.
This invention relates to a bearing seal. It more par-
ticularly relates to bearing seals of the type used for sealing axle
bearings on rail cars. Reference may be had to Figures 1, 2
and 3 of the drawings herein which, apart from the bearing seal,
illustrate an axle box arrangement well known in the prior art.
It is commonly known to have a sealing ring which is adapted to
be inserted into a seal pocket of an axle box and which is made
of a resilient material, and further which is provided with an
aperture adapted to suit the diameter of the axle for accommodat-
ing the axle, the sealing ring comprising an inner ring heldresiliently and displaceably within an outer carrier.
In the above-mentioned prior art example arrangement,
the edge of the surface of the outer carrier facing the axle-box
housing is provided with peripheral sealing ribs which, after
the carrier has been mounted in the pocket, bear against the
wall surface of the axle-box housing.
The major disadvantage of this known arrangement is
that the pre-load, produced by the material of which the carrier
is made, against the wall surface of the axle-box housing is not
always sufficient to prevent the lubricant in the axle-box
housing from escaping into the pocket.
It is therefore a prime object of the present invention
to provide a bearing seal of the type discussed above which
provides complete sealing of the axle-box housing, even wherein
the design of axle-box housings and pockets vary, and also to
ensure ease of assembly of the seal.
According to the present invention, this purpose is
achieved in that the carrier is provided, in the vicinity of
the inner ring and on both sides thereof, with resilient
peripheral sealing ribs or the like ~hich, in the assembled
condition, bear with their outer edges, around their entire
peripheries and under pre-load, against the two opposing walls
~08~546
of the pocket in the axle-box housing.
This arrangement ensures a reliable seal within the
pocket in the axle-box housing, without any additional carrier
retainers or tensioning devices.
It is desirable, in this connection, for the sealing
ribs arranged on both sides, to be arranged as close as possible
to the inner ring of the carrier, i.e., they should surround the
inner ring circularly and should be equidistant therefrom.
Additional sealing ribs of this kind may be provided,
preferably three in number arranged concentrically.
As a variation of the arrangement, according to the
present invention, additional sealing may be obtained by
providing apexed outer surfaces in the vicinity of the groove
in the inner ring provided, in this arrangement, for the
accommodation of sealing twine and facing the axle, the internal
edges of the said outer surfaces forming lip seals and bearing
against the axle. This arrangement may be such that, in the
initial operating condition, only the sealing means, i.e., the
sealing twine, located in the groove, bears against the axle in
order to provide a seal, but as soon as this seal becomes worn,
the lip seals bear against the axle and take over the sealing
function. This extends the life of the seal according to the
present invention considerably. For this reason, the inside
diameter of the annular lip seals must be smaller than the
outside diameter of the axle in the vicinity of the sealing
surface.
For the purpose of improving still further the sealing
of the carrier in the pocket in the axle-box housing, and also to
ensure accurate positioning, it is desirable to provide, in
addition to the sealing ribs surrounding the inner ring, support
ribs which are arranged on both sides of the carrier surfaces
and which run around in the vicinity of the edges of the carrier.
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In order that this may not in any way impair the action of the
sealing ribs, it is desirable for these support ribs to be rather
shorter in cross section, and possibly also stiffer, than the
peripheral sealing ribs as shown in Figure 3.
Here again, a plurality of support ribs, running
parallel and concentrically with each other, may be provided,
with two or three support ribs arranged side by side.
Furthermore, an additional sealing rib may be arranged
at least in the vicinity of the closing edge of the carrier, the
width of the said rib corresponding to the width of the sealing
ribs of the inner ring. The purpose of this additional sealing
rib is to close off and seal the top of the pocket, thus prevent-
ing the entry of any dust or dirt. For--this purpose, the ends of
the upper sealing rib may be provided with overhanging flaps which
bear against the end and outer surfaces of the pocket defining
the slot therein.
The two vertical edges of this carrier, adjacent the
upper horizontal edge thereof, may also be provided with sealing
ribs of this kind which can extend at least as far as the
peripheral sealing ribs in the vicinity of the inner ring. In
addition to their sealing function, these two vertical sealing
ribs may provide additional guidance and retention of the carrier
in the pocket.
In the case of the bearing seal according to the
present invention, the resiliency of the inner ring is particularly
produced by, among other things, the carrier being cup-shaped and
thus constituting a bellows-like retainer for the inner ring.
According to another example of embodiment, a bellows-like fold
surrounding the inner ring is arranged in the plane of the carrier,
so that the central plane of the inner ring also lies in the
central plane of the carrier. The results of practical tests
have shown that a single fold is sufficient, but more may be
provided if desired.
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108~46
For convenience, the carrier may also be of the same
shape as the axle-box pocket, i.e., it may, if desired, be
substantially rectangular, so that even below the inner ring -
and the peripheral sealing ribs, the corners of the pocket are
filled by the carrier and its support ribs. This prevents the
formation of an oil sump in the lower part of the pocket.
In this case, in particular, the shape of the carrier
may be such that the undersurface thereof lies against the bottom
of the pocket, under pre-load, in the assembled condition with
the axle inserted.
In accordance with one aspect of the present invention,
there is provided a bearing seal for the axle bearings of rail
vehicles, the said seal having a sealing ring adapted to be
inserted into a pocket in the axle-box, the said sealing ring
being made of a resilient material and comprising an opening
matching the diameter of the axle and accommodating the said
axle, and an inner ring which is held, with the interposition
of a bellows-li~e fold, resiliently and displaceably in an outer
carrier integral with the said inner ring, the said carrier
being sealed with sealing means into the axle-box pocket, charac-
terized in that the sealing means consist, in a manner known
per se, of sealing ribs which are arranged on each side of the
carrier, which surround the inner ring circularly, and whlch
are at an equal distance therefrom, and in that provided in
addition to the sealing ribs surrounding the inner ring are
support ribs which are arranged, on both sides, upon the sur-
faces of the carrier, and which run in the vicinity of the
edges of the said carrier, the said support ribs being somewhat
shorter in cross-section than the sealing ribs surrounding the
inner ring.
~ he invention is illustrated by way of example in the
following drawings wherein:
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Figure 1 is an oblique view of an axle box in which
the invention is used,
Figure 2 is a cross-sectional elevation of the
sealing ring according to the invention,
with its carrier, inserted into the pocket
in the axle-box housing; and
Figure 3 is a cross-section taken along line III-III
in Figure 2.
Figure 1 illustrates an axle-bearing housing, having a
so-called axle-box 1 in which a bearing bush 2, stepped in
relation to the housing, is displaceably arranged and which
serves to absorb the wheel forces transferred through stub-axle 3.
Adjacent where axle 3 enters axle-box 1, there is provided an
upwardly-facing open pocket 4 in which a sealing ring 5 (see
Figure 2) may be inserted. Axle-box 1 is filled with lubricant,
and the purpose of sealing ring 5 is to prevent the escape of
lubricant to the axle or wheel, i.e., towards the right in
Figure 1.
Referring to the embodiment illustrated in Figure 2, a
carrier 25 for sealing ring 5 is provided, in the vicinity of
inner ring 26, having resilient peripheral sealing ribs 27, outer
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108454~
edges 27a (see Figure 3) of which, when the seal is assembled,
bear, around their entire peripheries, under pre-load, against
the ~pposing walls of pocket 4 in axle-box housing 1. As shown,
this example of embodiment has three sealing ribs 27 arranged
concentrically with inner ring 26.
In addition to sealing ribs 27, support ribs 28 are
provided on both sides of carrier 25, said support ribs, as shown
in Figure 3, are cross-sectionally shorter, and possibly stiffer,
than sealing ribs 27. These support ribs 28 are located in the
vicinity of the edges of carrier 25 and parallel therewith. In
the example illustrated and which is best seen in Figure 2, there
are two support ribs at the top and three at the bottom. Where
sealing ribs 27 reach the outer edges of carrier 25, they replace
said support ribs 28, i.e., in these areas the support ribs 28
end in front of the peripheral sealing ribs 27.
Located in the vicinity of the upper pocket closing
edge of carrier 25 is a further sealing rib 29, the width of
which is equal to that of inner ring sealing ribs 27. Sealing
rib 29 is designed to close off the top of pocket 4, being
provided, for this purpose, with projecting flaps 29a at respective
ends thereof, said flaps 29a bearing against the ends and outer
surfaces defining the entry 4a into pocket 4, and against the
corresponding inner wall of said pocket.
Furthermore, the vertical edges of carrier 25, adjacent
the top horizontal edge thereof, may also be provided with
vertical sealing ribs 30 which extend, as shown in the example
illustrated, as far as inner ring sealing ribs 27. Below sealing
ribs 27, sealing rib 30 is replaced by an additional support rib 28.
In order to keep the inner ring mobile, that is so that
it is held resiliently and displaceably within the carrier, a
peripheral bellows-like fold 31, surrounding inner ring 26, is
arranged in the plane of carrier 25, so that, as shown in Figure 3,
the central plane of inner ring 26 lies in the central plane of
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carrier 25.
As shown in Figure 2, the shape of carrier 25 matches
that of pocket 4 and is substantially rectangular. Thus corners 25a
of carrier 25 also fill up the pocket, bottom surface 25b (Figure
3) bearing, with pre-load, against bottom 32 of the pocket 4, when
the seal is in position, with axle 3 inserted therein. Tabs 33
along the top of carrier 25 facilitate the handling of the carrier
when it is being inserted into, or remc~ed from, pocket 4.
Figure 3 as mentioned, is a cross section taken along
the line III-III in Figure 2, from which it may be seen that inner
ring 26 has an outwardly-open groove 34 carrying a spiral spring
35 made of steel wire or the like. The inside of inner ring 26
is provided with groove 36 carrying a sealing means such as twine
37 or the like which, when axle 3 is in position, bears, under
pre-load, against the sealing surface of the axle. After sealing
twine 37 has become worn to a certain extent, lip seals 38 begin
to bear against the sealing surface of the axle, these lip seals
being formed by apexed outer surfaces of the bore of inner ring 26
adjacent the sides of inner ring 26 and located in the vicinity of
groove 36. After some wear has taken place in sealing twine 37,
this twine and lips 38 bear jointly against the sealing surface of
axle 3, thus ensuring complete sealing. To this end, the inside
diameter of lip seals 38 is smaller than the diameter of the axle
in the vicinity of the sealing surface.
Figure 3 also shows the design of peripheral fold 31
and that sealing ribs 27 and 29 are longer in cross section than
support ribs 28.
As shown, outer edges 27a of ribs 27 and outer edges
29b of ribs 29 bear, under pre-load, against the opposing walls
4b of pocket 4.
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