Note: Descriptions are shown in the official language in which they were submitted.
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A BEARING ASSEMBLY
FIELD OF THE INVENTION
This invention relates to a bearing. In particular, the invention relates to a
bearing
assembly and to a bearing.
BACKGROUND
In the field of mechanical apparatus, and the like, use is often made of
bearings to
inhibit wear between parts, or components, or the like, which move relative to
each other
while in contact with each other. In some cases, components are arranged to be
in sliding
contact with each other. For example, in the case of mechanical hoisting
apparatus, rope
conveyance apparatus, elevators, or lifts, and the like, elongate elements,
such as steel
wire wound ropes, or cables, and the like, are often guided through the
apparatus and
make sliding contact with the apparatus when in use.
In the case of conveyances arranged to travel along a constrained path defined
by
an elongate element, such as a wire wound rope, or cable, or the like, the
conveyance is
often guided along the elongate element by means of a constraining mechanism
on the
conveyance. The constraining mechanism is typically arranged to run along the
elongate
element so as to guide the conveyance along the elongate element. Frictional
contact
typically takes place between the elongate element and the constraining
mechanism as the
conveyance is guided along the elongate element. In some cases constraining
mechanisms make use of guide rollers arranged to roll along the elongate
element. In
other cases constraining mechanisms make use of longitudinal low friction
material
slippers, or slide bearings.
It has been found that constraining mechanisms making use of guide rollers
provide relatively low frictional resistance but are relatively maintenance
intensive.
Furthermore, constraining mechanisms making use of guide rollers typically
have rather
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bulky and relatively complicated support structures which are sometimes
impractical. In
the case of longitudinal low friction material slippers, or slide bearings, it
has been found
that constraining mechanisms which make use thereof suffer from relatively
high rates of
wear and cause the elongate element to suffer from wear as well.
Traditionally, the materials of which the longitudinal low friction material
slippers have been made have been relatively soft to inhibit wear on the
elongate element.
Such materials include non-magnetic metals, such as brass, bronze, and the
like, as well
as plastics, nylons, urethanes and the like. Although such materials inhibit
wear on the
elongate element, these materials have been found to exhibit relatively high
wear rates
resulting in relatively high levels of consumption, frequent operational
downtime and
relatively high production cost losses, in certain cases. Attempts have been
made to
provide lubrication between the elongate element and such constraining
mechanisms, but
these attempts have met with limited success. The use of relatively soft
magnetic metals
has been investigated. However, such metals typically have higher coefficients
of
friction than the non magnetic metals mentioned above which typically causes
higher
wear rates of the elongate element which is undesirable.
It is an object of this invention to provide a constraining mechanism which
is simpler than those which make use of guide rollers and which has a lower
rate of wear
than the constraining mechanisms of the longitudinal low friction material
slipper type.
SUMMARY OF THE INVENTION
According to the invention, there is provided a bearing assembly including a
bearing mount and a bearing on the bearing mount, the bearing being of a
ceramic
material.
The bearing may be defined by a plurality of ceramic tiles secured on the
bearing
mount.
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The bearing may be of a moulded ceramic material.
The bearing may be secured on the bearing mount by bonding. Instead, or in
addition, the bearing may be secured on the bearing mount by mechanical means.
The bearing may be secured on the bearing mount by mechanical means in the
form of screw-threaded fasteners.
The bearing may be defined by at least two parts.
The bearing mount may be defined by at least two parts releasably secured
together to enable the parts to be separated from one another.
The bearing may be defined between the two parts of the bearing mount and may
define a passage extending through the bearing assembly when the two parts of
the
bearing mount are releasably secured together.
The bearing may be releasably mounted on the bearing mount.
The bearing mount may include at least two parts releasably secured together
to
enable the parts to be separated so as to enable the bearing to be removed
from the
bearing mount.
The bearing mount may define a bearing seat when the two parts are releasably
secured together, on which bearing seat the bearing is releasably mounted.
Each part of the bearing mount may define a cross-sectionally generally semi-
circular shaped surface such that when the parts of the bearing mount are
releasably
secured together, the bearing mount defines a cross-sectionally generally
circular shaped
bearing seat.
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The parts of the bearing mount may be releasably secured together by means of
conventional screw-threaded fasteners.
The bearing may define an outer cross-sectionally generally circular shaped
surface arranged to seat between the bearing surfaces of the parts of the
bearing mount
when the parts of the bearing mount are secured together.
The bearing may define an internal bearing passage extending therethrough, the
passage being arranged to receive an elongate component in sliding
relationship
therethrough.
The bearing passage may be cross-sectionally generally circular in shape.
The bearing may be elongate and may define a collar formation projecting
radially
outwardly from at least one end. The bearing may define a collar formation
projecting
radially outwardly from each end.
The bearing may be defined by at least two parts. Each part of the bearing may
be
elongate and may define a cross-sectionally generally semi-circular axially
extending
outer and inner surface.
According to another aspect of the invention, there is provided a bearing
including
a body formed from a ceramic material.
The body may be elongate.
The body may define an axially extending cross-sectionally part circular outer
surface. The body may define an axially extending cross-sectionally generally
semi-
circular outer surface.
The body may define an axially extending cross-sectionally part circular inner
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surface. The body may define an axially extending cross-sectionally generally
semi-
circular inner surface.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described, by way of example, with reference to the
accompanying diagrammatic drawings, in which:
Figure 1 shows a schematic end view of a bearing assembly in accordance with
the invention;
Figure 2 shows a schematic plan view of the bearing assembly shown in Figure
1;
Figure 3 shows a schematic side view of the bearing assembly shown in Figures
1
and 2;
Figure 4 shows a schematic three-dimensional exploded view of another bearing
assembly in accordance with the invention; and
Figure 5 shows a schematic three-dimensional exploded view of yet another
bearing assembly in accordance with the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to Figures 1 to 3 of the drawings, a bearing assembly, in accordance
with the invention, is generally indicated by reference numeral 10. The
bearing assembly
can typically be used as a constraining mechanism in a high speed winding
operation,
or the like, or another kind of conveyance, for example. When used for such a
purpose,
the assembly 10 is typically mounted on a conveyance apparatus, or structure,
schematically indicated at 11. It is envisaged that the assembly 10 can
advantageously be
used in hoisting, rope conveying and elevator applications. However, it is to
be
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appreciated that the bearing assembly of the invention is not limited for use
as a
constraining mechanism in such applications only, but extends to use as a
slide bearing in
general.
The bearing assembly 10 includes a bearing mount, generally indicated by
reference numeral 12, and a bearing 14. The bearing 14 is on the bearing mount
12 and is
of a ceramic material. The mount 12 can typically be of metal.
The bearing 14 can be of a moulded ceramic material. The bearing 14 can be
cast
to any desired shape or size depending on the application. The bearing 14 can
be defined
by a plurality of ceramic tiles or strips secured on the bearing mount 12. The
bearing 14
can be secured on the bearing mount 12 by bonding. Instead, or in addition,
the bearing
14 can be secured on the bearing mount 12 by any appropriate mechanical
arrangement.
Instead, the bearing 14 can be defined by at least two parts 14.1, 14.2. The
parts
14.1, 14.2 of the bearing 14 can be secured on the bearing mount 12 by
mechanical
means, such as by means of screw-threaded fasteners, or the like, for example.
Instead,
or in addition, the parts can be secured on the bearing mount 12 by bonding.
The bearing mount 12 is typically defined by two parts 12.1, 12.2. The parts
12.1,
12.2 are secured to one another releasably to enable the parts 12.1, 12.2 to
be separated
from one another. The bearing 14 is defined between the two parts 12.1, 12.2
of the
bearing mount 12 and defines a bearing passage 16 extending through the
bearing
assembly 10 when the two parts 12.1, 12.2 of the bearing mount 12 are
releasably secured
together. The passage 16 is arranged to receive an elongate component, such as
an
elongate element 17 in the form of a wire wound rope, or the like, for
example, in sliding
relationship therethrough. The bearing passage 16 is typically cross-
sectionally generally
circular in shape. It will be appreciated that when the element 17 is received
in sliding
relationship in the passage 16, the axial movement along the element 17 can be
achieved
but lateral movement relative to the element 17 is inhibited.
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In one embodiment, the bearing 14 is releasably mounted on the bearing mount
12. Accordingly, in such a case, the bearing 14 can be removed and replaced by
separating the parts 12.1, 12.2 of the bearing mount 12 from one another. The
parts 12.1,
12.2 can be secured relative to one another by means of conventional screw-
threaded
fasteners, such as bolts, screws, or the like, extending through apertures 18.
The bearing mount 12 defines a bearing seat 20 when the two parts 12.1, 12.2
are
releasably secured together. Tlie bearing 14 is seated on the bearing seat 20
releasably.
Each part 12.1, 12.2 of the bearing mount 12 defines a cross-sectionally
generally semi-
circular shaped surface 20.1, 20.2 such that when the parts 12.1, 12.2 of the
bearing
mount 12 are releasably secured together, the bearing mount 12 defines a cross-
sectionally generally circular shaped bearing seat 20. The bearing 14 defines
an outer
cross-sectionally generally circular shaped surface arranged to seat between
the bearing
surfaces 20.1, 20.2 of the parts 12.1 12.2 of the bearing mount 12 when the
parts of the
bearing mount 12 are secured together.
Referring now to Figure 4 of the drawings, in which like reference numerals
have
been used to designate similar parts, unless otherwise stated, another bearing
assembly in
accordance with the invention is generally indicated by reference numeral 110.
The
bearing assembly 110 is similar to the assembly 10 save that the one part
112.2 of the
bearing mount 112 of the assembly 110 has flange formations 113.1, 113.2.
As can best be seen in Figure 4, the bearing 14 has a body formed from a
ceramic
material. The body can typically be made up of two parts 14.1, 14.2 as already
mentioned. When mounted on the mount 112 the parts 14.1, 14.2 together form
the
bearing 14. Each bearing part 14.1, 14.2 defines an elongate body having an
axially
extending cross-sectionally part circular, preferably generally semi-circular,
outer surface
14.3. Each bearing part 14.1, 14.2 further defines an axially extending cross-
sectionally
part circular, preferably generally semi-circular, inner surface 14.4. When in
a mouiited
condition on the mount 112, the inner surfaces 14.4 together define the
passage 16
through which the elongate component 17 can extend.
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Referring now to Figure 5 of the drawings, in which like reference numerals
have
been used to designate similar parts, unless otherwise stated, another bearing
assembly in
accordance with the invention, is generally indicated by reference numeral
210. The
bearing assembly 210 is similar to the bearing assembly 110, save that the
bearing 114 of
the assembly 210 has two parts 114.1, 114.2 each part being elongate and
defining a
collar formation 114.3, 114.4 projecting radially outwardly from each end
114.5, 114.6.
The collar formations 114.3, 114.4 serve to hold the bearing parts, or
inserts, 114.1, 114.2
captive on the bearing mount 112 when in a mounted condition.
It will be appreciated that by providing the mount 12, 112 and the bearing 14,
114
in split form, the assemblies 10, 110, 210 can be disassembled and assembled
around an
elongate component, such as the component 17, without having to thread the
component
through an aperture such as the passage 16. In certain cases, such as where
the elongate
element, or guidance system, is fixed as in the case of a rail like elongate
element as
opposed to flexible as in the case of a rope-like elongate element, the
bearing assembly of
the invention need not necessarily surround the whole circumference of the
elongate
element, but can be arranged to extend around the elongate element by a
sufficient
amount to inhibit the elongate element form escaping laterally. Accordingly,
the bearing
assembly can be arranged to extend around the elongate element for about 270 ,
or the
like.
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