U.S. patent application number 16/160089 was filed with the patent office on 2019-08-29 for high-speed ball bearing and ball retainer.
The applicant listed for this patent is TUNG PEI INDUSTRIAL CO.,LTD.. Invention is credited to BO-RONG LEE, LI-CHUAN LIN.
Application Number | 20190264744 16/160089 |
Document ID | / |
Family ID | 64568266 |
Filed Date | 2019-08-29 |
United States Patent
Application |
20190264744 |
Kind Code |
A1 |
LIN; LI-CHUAN ; et
al. |
August 29, 2019 |
HIGH-SPEED BALL BEARING AND BALL RETAINER
Abstract
A high-speed ball bearing includes an outer ring, an inner ring,
a plurality of balls, and a ball retainer. The ball retainer
includes a plurality of pocket holes for arranging a plurality of
balls, an inner circumferential surface of each of the pocket holes
have a spherical surface is coaxial to the ball. A gap between an
outer circumferential surface of the ball retainer and an inner
circumferential surface of the ring is defined as a first gap, and
a gap between the pocket hole and the corresponding ball is defined
as a second gap. The first gap and the second gap have the
following relationship: W2=(W1-r').times.A.
Inventors: |
LIN; LI-CHUAN; (Taoyuan
City, TW) ; LEE; BO-RONG; (Taipei City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TUNG PEI INDUSTRIAL CO.,LTD. |
Taipei City |
|
TW |
|
|
Family ID: |
64568266 |
Appl. No.: |
16/160089 |
Filed: |
October 15, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16C 33/3856 20130101;
F16C 19/163 20130101; F16C 33/32 20130101; F16C 33/3806 20130101;
F16C 33/3887 20130101; F16C 33/664 20130101; F16C 2360/24 20130101;
F16C 33/6607 20130101; F16C 33/44 20130101; F16C 2300/22
20130101 |
International
Class: |
F16C 33/38 20060101
F16C033/38; F16C 33/32 20060101 F16C033/32; F16C 33/44 20060101
F16C033/44; F16C 33/66 20060101 F16C033/66 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 26, 2018 |
TW |
107202618 |
Claims
1. A high-speed ball bearing, comprising: an outer ring having an
outer ring track surface arranged on an inner circumferential
surface of the outer ring, the inner circumferential surface having
an outer ring shoulder arranged around a central axis of the ball
bearing, wherein a diameter of an inner circumferential surface of
the outer ring shoulder is smaller than a diameter of an inner
circumferential surface of the outer ring track surface; an inner
ring having an inner ring track surface arranged on an outer
circumferential surface of the inner ring; a plurality of balls
rollably disposed between the outer ring track surface and the
inner ring track surface, wherein the balls are spaced apart from
each other, and each two of the balls arranged adjacent to each
other have the same angle with respect to the central axis of the
ball bearing; and a ball retainer arranged between the inner
circumferential surface of the outer ring and the outer
circumferential surface of the inner ring, the ball retainer
including a first ring portion and a second ring portion, wherein
the first ring portion and the second ring portion are arranged
around the central axis of the ball bearing, a diameter of an outer
circumferential surface of the first ring portion is larger than a
diameter of an outer circumferential surface of the second ring
portion, and a diameter of an inner circumferential surface of the
first ring portion is larger than or equal to a diameter of an
outer circumferential surface of the second ring portion, wherein
the ball retainer includes a plurality of pocket holes that are in
an annular arrangement between the first ring portion and the
second ring portion, and each two of the pocket holes arranged
adjacent to each other have the same angle and are spaced apart
from each other with respect to the central axis of the ball
bearing, wherein the positions and diameters of the pocket holes
correspond to the positions and diameters of the balls, so that the
balls are arranged in the pocket holes, and when the balls roll
between the outer ring track surface and the inner ring track
surface, each adjacent two of the balls are maintained at a
distance from each other and have the same angle with respect to
the central axis of the ball bearing; wherein the outer
circumferential surface of the first ring portion of the ball
retainer is adjacent to the inner circumferential surface of the
outer ring shoulder, a gap between the first ring portion and the
inner circumferential surface of the outer ring shoulder is defined
as a first gap, and a gap between the inner circumferential surface
of each of the pocket holes and the corresponding ball is defined
as a second gap, wherein the first gap and the second gap have the
following relationship: W2=(W1-r').times.A; wherein W1 represents a
width of the first gap; W2 represents a width of the second gap; r'
is an expansion variable of a radius of the ball retainer generated
by the ball bearing being rotated at a predetermined speed; A
represents an amplification factor, and wherein when a product
value DmN obtained by multiplying the pitch diameter Dm of the
high-speed ball bearing and a predetermined allowable rotation
speed N is 1,600,000, the amplification factor is within a range of
1.2 to 1.5.
2. The high-speed ball bearing according to claim 1, wherein each
of the pocket holes is formed by a first notch arranged on one side
of the first ring portion and a second notch arranged on the second
ring portion, wherein in each of the pocket holes, an inner
circumferential surface of the first notch and an inner
circumferential surface of the second notch face toward each other,
the first notch has a first spherical surface arranged on the inner
circumferential surface of the first notch, and the second notch
has a second spherical surface arranged on the inner
circumferential surfaces of the second notch, wherein in each of
the pocket holes and the corresponding ball, a center of the ball
defines an imaginary spherical surface, a diameter of the imaginary
spherical surface is larger than a diameter of the ball, and the
first spherical surface and the second spherical surface are
arranged on the imaginary spherical surface.
3. The high-speed ball bearing according to claim 2, wherein the
width of the second gap is within a range of 0.3 mm to 0.5 mm.
4. The high-speed ball bearing according to claim 3, wherein the
ball retainer and the balls are covered with a lubricating oil
during rotation.
5. The high-speed ball bearing according to claim 3, wherein the
amplification factor is 1.4.
6. The high-speed ball bearing according to claim 3, wherein the
ball retainer is made of a resin material or a nylon material.
7. A ball retainer for being arranged in a ball bearing that
includes a plurality of balls, wherein the ball bearing includes an
outer ring and an inner ring, and the outer ring has an outer ring
track surface arranged on an inner circumferential surface of the
outer ring that has an outer ring shoulder arranged around a
central axis of the inner circumferential surface of the outer ring
of the ball bearing, wherein a diameter of an inner circumferential
surface of the outer ring shoulder is smaller than a diameter of an
inner circumferential surface of the outer ring track surface, and
the inner ring has an inner ring track surface arranged on an outer
circumferential surface of the inner ring, wherein the balls are
rollably disposed between the outer ring track surface and the
inner ring track surface, the balls are spaced apart from each
other, and each two of the balls arranged adjacent to each other
have the same angle with respect to the central axis of the ball
bearing; the ball retainer comprising; a first ring portion and a
second ring portion that are configured to be arranged around a
central axis of the ball bearing, wherein a diameter of an outer
circumferential surface of the first ring portion is larger than a
diameter of an outer circumferential surface of the second ring
portion, and a diameter of an inner circumferential surface of the
first ring portion is larger than or equal to a diameter of an
outer circumferential surface of the second ring portion; and a
plurality of pocket holes being in an annular arrangement between
the first ring portion and the second ring portion, wherein each
two of the pocket holes arranged adjacent to each other have the
same angle with respect to the central axis of the ball retainer,
and are spaced apart from each other, wherein the positions and
diameters of the pocket holes correspond to the positions and
diameters of the balls, so that the balls are respectively arranged
in the pocket holes, and when the balls roll between the outer ring
track surface and the inner ring track surface, and each adjacent
two of the balls are maintained at a distance from each other and
have the same angle with respect to the central axis of the ball
bearing; wherein the outer circumferential surface of the first
ring portion of the ball retainer is arranged adjacent to the inner
circumferential surface of the outer ring shoulder, a gap between
the first ring portion and the inner circumferential surface of the
outer ring shoulder is defined as a first gap, and a gap between
the inner circumferential surface of each of the pocket holes and
the corresponding ball is defined as a second gap, wherein the
first gap and the second gap have the following relationship:
W2=(W1-r').times.A; wherein W1 represents a width of the first gap;
W2 represents a width of the second gap; r' is an expansion
variable of a radius of the ball retainer generated by the ball
bearing being rotated at a predetermined speed; A represents an
amplification factor, and wherein when a product value DmN obtained
by multiplying the pitch diameter Dm of the high-speed ball bearing
and a predetermined allowable rotation speed N is 1,600,000, the
amplification factor is within a range of 1.2 to 1.5.
8. The ball retainer according to claim 7, wherein each of the
pocket holes is formed by a first notch arranged on one side of the
first ring portion and a second notch arranged on the second ring
portion, wherein in each of the pocket holes, an inner
circumferential surface of the first notch and an inner
circumferential surface of the second notch face toward each other,
the first notch has a first spherical surface arranged on the inner
circumferential surface of the first notch, and the second notch
has a second spherical surface arranged on the inner
circumferential surfaces of the second notch, wherein in each of
the pocket holes and the corresponding ball, a center of the ball
defines an imaginary spherical surface, and the first spherical
surface and the second spherical surface are arranged on the
imaginary spherical surface.
9. The ball retainer according to claim 8, wherein the width of the
second gap is within a range of 0.3 mm to 0.5 mm.
10. The ball retainer according to claim 8, wherein the
amplification factor is 1.4.
11. The ball retainer according to claim 8, wherein the ball
retainer is made of a resin material or a nylon material.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATION
[0001] This application claims the benefit of priority to Taiwan
Patent Application No. 107202618, filed on Feb. 26, 2018. The
entire content of the above identified application is incorporated
herein by reference.
[0002] Some references, which may include patents, patent
applications and various publications, may be cited and discussed
in the description of this disclosure. The citation and/or
discussion of such references is provided merely to clarify the
description of the present disclosure and is not an admission that
any such reference is "prior art" to the disclosure described
herein. All references cited and discussed in this specification
are incorporated herein by reference in their entireties and to the
same extent as if each reference was individually incorporated by
reference.
FIELD OF THE DISCLOSURE
[0003] The present disclosure relates to a ball bearing and a ball
retainer, and more particularly to a high-speed ball bearing and a
ball retainer each applied to a high-speed rotating shaft.
BACKGROUND OF THE DISCLOSURE
[0004] Since a ball bearing has a good operating performance, which
includes a high load, a low frictional resistance, a small
rotational deflection, and a high rigidity, a high-speed rotating
system generally uses the ball bearing as a support member for
supporting a rotating shaft. This can prevent high-speed rotation
of the high-speed rotating system from causing temperature rise and
friction loss issues.
[0005] With the rapid development of related industries such as the
machinery industry or the aviation industry, one of the current
trends in industrial development includes promotion of the
rotational speed of the rotating shaft and improvement of the
working efficiency of the rotating system. Moreover, with the
development of mechanical processing technology, the precision
requirements of the rotating shaft have gradually increased, so
that the high-speed performance and the precision of the ball
bearing need to be improved for achieving the requirements of the
rotational speed and precision of the mechanical rotating
shaft.
[0006] The high-speed performance and precision of the ball bearing
are not only affected by the material and machining precision of
the ball bearing, but also affected by the structure of the ball
bearing. A typical ball bearing includes an outer ring, an inner
ring, a plurality of balls, and a ball retainer. The ball retainer
is used to separate the balls from each other, so that the balls
can be arranged on ball tracks between the inner ring and the outer
ring and spaced apart from each other, and each two of the balls
arranged adjacent to each other have the same angle with respect to
the central axis. The ball retainer is approximately in an annular
shape and includes a plurality of pocket holes that are in an
annular arrangement for receiving the balls, and each two of the
pocket holes arranged adjacent to each other have the same angle
with respect to an axis and are spaced apart from each other. In
order to allow the balls to be rollable in the pocket holes of the
ball retainer, and a diameter of each of the pocket holes of the
ball retainer needs to be larger than an outer diameter of the
corresponding ball. However, a gap will exist between each of the
pocket holes of the ball retainer and the corresponding ball.
Accordingly, when the ball bearing is in operation, the ball
retainer and the balls can still be movable relative to each
other.
[0007] Generally, the conventional ball retainer has two guiding
modes. One of the two guiding modes is a steel ball guiding mode,
which usually does not consider that the ball bearing is prone to
deflect and interfere with the balls under a high-speed operation.
The other guiding mode is an outer ring guiding mode, and can be
used to stabilize, balance, and reduce the deflection under a
high-speed operation. However, the ball retainer of the outer ring
guiding mode will brush against the outer ring under a low speed
operation so that the ball bearing in each of the two guiding modes
is met with increased resistance during operation and generates
additional vibrations, affecting the stability and precision of the
ball bearing operation.
SUMMARY OF THE DISCLOSURE
[0008] In response to the above-referenced technical inadequacies,
the present disclosure provides a high-speed ball bearing and a
ball retainer to effectively improve the issues associated with
conventional ball bearings. Specifically, the issues associated
with the conventional ball bearings includes that the ball retainer
is easily deflected under a high-speed rotation to generate
vibration, and the ball retainer may be in abnormal contact with an
outer ring under a low-speed rotation.
[0009] In one aspect, the present disclosure provides a high-speed
ball bearing, which includes an outer ring, an inner ring, a
plurality of balls, and a ball retainer. The outer ring has an
outer ring track surface arranged on an inner circumferential
surface thereof, and the inner circumferential surface of the outer
ring has an outer ring shoulder arranged around a central axis of
the ball bearing. A diameter of an inner circumferential surface of
the outer ring shoulder is smaller than a diameter of an inner
circumferential surface of the outer ring track surface. The inner
ring has an inner ring track surface arranged on an outer
circumferential surface thereof. The balls are rollably disposed
between the outer ring track surface and the inner ring track
surface and are spaced apart from each other, and each two of the
balls arranged adjacent to each other have the same angle with
respect to the central axis of the ball bearing. The ball retainer
is arranged between the inner circumferential surface of the outer
ring and the outer circumferential surface of the inner ring, and
the ball retainer includes a first ring portion and a second ring
portion, which are configured to be arranged around the central
axis of the ball bearing. A diameter of an outer circumferential
surface of the first ring portion is larger than a diameter of an
outer circumferential surface of the second ring portion, and a
diameter of an inner circumferential surface of the first ring
portion is larger than or equal to a diameter of an outer
circumferential surface of the second ring portion. The ball
retainer further includes a plurality of pocket holes, the pocket
holes are in an annular arrangement between the first ring portion
and the second ring portion, and each two of the pocket holes
arranged adjacent to each other have the same angle with respect to
the central axis of the ball bearing, and are spaced apart from
each other. The positions and diameters of the pocket holes
correspond to the positions and diameters of the balls, so that the
balls can be arranged in the pocket holes. When the balls roll
between the outer ring track surface and the inner ring track
surface, each two of the balls are maintained at a distance from
each other and have the same angle with respect to the central axis
of the ball bearing. The outer circumferential surface of the first
ring portion of the ball retainer is adjacent to the inner
circumferential surface of the outer ring shoulder. A gap between
the first ring portion and the inner circumferential surface of the
outer ring shoulder is defined as a first gap, and a gap between
the inner circumferential surface of each of the pocket holes and
the corresponding ball is defined as a second gap. The first gap
and the second gap have the following relationship:
W2=(W1-r').times.A. W1 represents a width of the first gap. W2
represents a width of the second gap r' is an expansion variable of
a radius of the ball retainer generated by the ball bearing being
rotated at a predetermined speed. A represents an amplification
factor, and when a product value DmN obtained by multiplying the
pitch diameter Dm of the high-speed ball bearing and a
predetermined allowable rotation speed N is 1,600,000, the
amplification factor is within a range of 1.2 to 1.5.
[0010] In certain embodiments, the present disclosure provides a
high-speed ball bearing. Each of the pocket holes is formed by a
first notch arranged on one side of the first ring portion and a
second notch arranged on the second ring portion. In each of the
pocket holes, an inner circumferential surface of the first notch
and an inner circumferential surface of the second notch face
toward each other. The first notch has a first spherical surface
arranged on the inner circumferential surface thereof, and the
second notch has a second spherical surface arranged on the inner
circumferential surfaces thereof. In each of the pocket holes and
the corresponding ball, a center of the ball defines an imaginary
spherical surface, a diameter of the imaginary spherical surface is
larger than a diameter of the ball, and the first spherical surface
and the second spherical surface are arranged on the imaginary
spherical surface.
[0011] In certain embodiments, the present disclosure provides a
high-speed ball bearing, where the width of the second gap is
within a range of 0.3 mm to 0.5 mm.
[0012] In certain embodiments, the present disclosure provides a
high-speed ball bearing. The ball retainer and the balls are
immersed into a lubricating oil during rotation.
[0013] In certain embodiments, the present disclosure provides a
high-speed ball bearing, where the amplification factor is 1.4.
[0014] In certain embodiments, the present disclosure provides a
high-speed ball bearing, where the ball retainer is made of a resin
material or a nylon material.
[0015] In one aspect, the present disclosure provides a ball
retainer for being arranged in the high-speed ball bearing.
[0016] Therefore, the advantageous effects of the present
disclosure are that an interference of the ball retainer on the
ball during high-speed operation can be effectively reduced, and a
deflection of the ball retainer can be effectively avoided, such
that the stability of the ball bearing can be effectively
improved.
[0017] These and other aspects of the present disclosure will
become apparent from the following description of the embodiment
taken in conjunction with the following drawings and their
captions, although variations and modifications therein may be
affected without departing from the spirit and scope of the novel
concepts of the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present disclosure will become more fully understood
from the detailed description and the accompanying drawings, in
which:
[0019] FIG. 1 is a perspective view of a high-speed ball bearing
according to an exemplary embodiment of the present disclosure;
[0020] FIG. 2 is a cross-sectional view taken along line II-II of
FIG. 1;
[0021] FIG. 3 is a cross-sectional view taken along line of FIG.
1;
[0022] FIG. 4 is a perspective view of a ball retainer according to
the exemplary embodiment of the present disclosure;
[0023] FIG. 5 is a partial-enlarged view of a pocket hole of the
ball retainer according to the exemplary embodiment of the present
disclosure; and
[0024] FIG. 6 is a partial-enlarged view of the high-speed ball
bearing showing the pocket hole of the ball retainer according to
the exemplary embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0025] The present disclosure is more particularly described in the
following examples that are intended as illustrative only since
numerous modifications and variations therein will be apparent to
those skilled in the art. Like numbers in the drawings indicate
like components throughout the views. As used in the description
herein and throughout the claims that follow, unless the context
clearly dictates otherwise, the meaning of "a", "an", and "the"
includes plural reference, and the meaning of "in" includes "in"
and "on". Titles or subtitles can be used herein for the
convenience of a reader, which shall have no influence on the scope
of the present disclosure.
[0026] The terms used herein generally have their ordinary meanings
in the art. In the case of conflict, the present document,
including any definitions given herein, will prevail. The same
thing can be expressed in more than one way. Alternative language
and synonyms can be used for any term(s) discussed herein, and no
special significance is to be placed upon whether a term is
elaborated or discussed herein. A recital of one or more synonyms
does not exclude the use of other synonyms. The use of examples
anywhere in this specification including examples of any terms is
illustrative only, and in no way limits the scope and meaning of
the present disclosure or of any exemplified term. Likewise, the
present disclosure is not limited to various embodiments given
herein. Numbering terms such as "first", "second" or "third" can be
used to describe various components, signals or the like, which are
for distinguishing one component/signal from another one only, and
are not intended to, nor should be construed to impose any
substantive limitations on the components, signals or the like.
[0027] Referring to FIG. 1 to FIG. 3, an exemplary embodiment of
the present disclosure provides a high-speed ball bearing 1 that
includes an outer ring 10, an inner ring 20, a plurality of balls
30, and a ball retainer 40.
[0028] As shown in FIG. 3, the outer ring 10 is annular in shape,
and has an outer ring track surface 11 arranged on an inner
circumferential surface thereof. The outer ring 10 has an outer
ring shoulder 12 that is arranged on one side of the inner
circumferential surface of the outer ring 10 around a longitudinal
axis of the ball bearing 1. A diameter of an inner circumferential
surface of the outer ring shoulder 12 is smaller than a diameter of
an inner circumferential surface of the outer ring track surface
11, and is smaller than a diameter of the inner circumferential
surface of the outer ring 10.
[0029] The inner ring 20 has an outer circumferential surface, and
a diameter of the outer circumferential surface of the inner ring
20 is smaller than a diameter of the inner circumferential surface
of the outer ring shoulder 12. The inner ring 20 has an inner ring
track surface 21 arranged on the outer circumferential surface
thereof, and the inner ring track surface 21 faces the outer ring
track surface 11. The balls 30 are arranged between the outer ring
10 and the inner ring 20. The balls 30 are rollably disposed
between the outer ring track surface 11 and the inner ring track
surface 21. The ball retainer 40 is arranged between the inner
circumferential surface of the outer ring 10 and the outer
circumferential surface of the inner ring 20. Since the balls 30
are disposed between the outer ring track surface 11 and the inner
ring track surface 21 by the ball retainer 40, the balls 30 are
spaced apart from each other, and each two of the balls 30 arranged
adjacent to each other have the same angle with respect to the
central axis of the ball bearing 1.
[0030] Referring to FIG. 4 and FIG. 5, the ball retainer 40 of the
present embodiment is preferably made of a resin material or a
nylon material. Further, the ball retainer 40 is approximately in
an annular shape, and includes a first ring portion 41 and a second
ring portion 42. The first ring portion 41 and the second ring
portion 42 are arranged sequentially around a longitudinal axis of
the ball bearing 1, and are connected to each other. A diameter of
an outer circumferential surface of the first ring portion 41 is
larger than a diameter of an outer circumferential surface of the
second ring portion 42. A diameter of an inner circumferential
surface of the first ring portion 41 is larger than or equal to a
diameter of the outer circumferential surface of the second ring
portion 42. In the present embodiment, the diameter of the inner
circumferential surface of the first ring portion 41 is equal to
the diameter of the outer circumferential surface of the second
ring portion 42, so that the inner circumferential surface of the
first ring portion 41 and the outer circumferential surface of the
second ring portion 42 are integrally connected to each other.
[0031] The ball retainer 40 includes a plurality of pocket holes
43. The pocket holes 43 are formed on the ball retainer 40 in an
annular arrangement, and each two of the pocket holes 43 arranged
adjacent to each other have the same angle with respect to the
central axis of the ball bearing 1, and are spaced apart from each
other. A diameter and a position of each of the pocket holes 43
correspond to a diameter and a position of each of the balls 30,
and the balls 30 are rollably received in the pockets 43.
Specifically, when the balls 30 roll between the outer ring track
surface 11 and the inner ring track surface 21, each two of the
balls 30 are maintained at a distance from each other and to have
the same angle with respect to the central axis of the ball bearing
1.
[0032] In the present embodiment, the pocket holes 43 are arranged
on the ball retainer 40 at a position between the first ring
portion 41 and the second ring portion 42. Each of the pockets 43
is formed by a first notch 431 arranged on one side of the first
ring portion 41 and a second notch 432 arranged on the second ring
portion 42. In the present embodiment, an inner circumferential
surface of the first notch 431 and an inner circumferential surface
of the second notch 432 face toward each other so as to jointly
define the pocket hole 43 in a circular shape, so that the balls 30
are respectively disposed in the pocket holes 43.
[0033] As shown in FIG. 5, which is a partial-enlarged view of the
ball retainer 40, the first notch 431 has a first spherical surface
433 arranged on the inner circumferential surface thereof, and the
second notch 432 has a second spherical surface 434 arranged on the
inner circumferential surface thereof. In each of the pocket holes
43 and the corresponding ball 30 of the present embodiment, the
first spherical surface 433 and the second spherical surface 434
face toward each other, a center of the ball 30 defines an
imaginary spherical surface P having a diameter D1 that is larger
than a diameter D2 of the ball 30, and the first spherical surface
433 and the second spherical surface 434 are arranged on the
imaginary spherical surface P. Accordingly, when the balls 30 are
disposed in the pocket holes 43, a gap can be maintained between
the first spherical surface 433 and the second spherical surface
434 of the pocket hole 43 and the ball 30, thereby allowing the
ball 30 to be rollable in the pocket hole 43.
[0034] Referring to FIG. 6, which shows the components of the
high-speed ball bearing 1 being in an assembled state, the outer
circumferential surface of the first ring portion 41 of the ball
retainer 40 is arranged adjacent to the inner circumferential
surface of the outer ring shoulder 12 of the outer 10. Moreover, a
first gap G1 is formed between the outer circumferential surface of
the first ring portion 41 and the inner circumferential surface of
the outer ring shoulder 12, and a second gap G2 is formed between
the first spherical surface 433 and the second spherical surface
434 of the inner circumferential surface of each of the pocket
holes 43 of the ball retainer 40 and the ball 30. A size of the
first gap G1 and a size of the second gap G2 are formed at a
specific ratio. When the high-speed ball bearing 1 is rotated at a
predetermined allowable rotational speed, the interference between
the ball retainer 40 and the balls 30 can be reduced, and the
vibration and the unbalanced state generated by the ball retainer
40 under a high-speed rotation can be reduced. Accordingly, the
stability of the high-speed ball bearing 1 of the present
disclosure under high-speed rotation can be improved.
[0035] In the present embodiment, the relationship between the
first gap G1 and the second gap G2 of the present disclosure can be
expressed by the following relational formula:
W2=(W1-r').times.A.
[0036] W1 represents a width of the first gap. W2 represents a
width of the second gap r' is an expansion variable of a radius of
the ball retainer generated by the high-speed ball bearing 1
rotated at a predetermined speed. A represents an amplification
factor, the amplification factor in the present embodiment is
within a range of 1.2 to 1.5.
[0037] In the above relational formula, the width W2 of the second
gap G2 needs to be determined, and the width W2 of the second gap
G2 is preferably within a range of 0.3 mm to 0.5 mm. In practice,
the high-speed ball bearing 1 can be lubricated by grease
infiltration, spraying, oil gas, or other manners, so that the ball
retainer 40 and the balls 30 can be covered with the lubricating
grease. When the width W2 of the second gap G2 of the high-speed
ball bearing 1 is within the range of 0.3 mm to 0.5 mm, the ball 30
and the inner circumferential surface (e.g., the first spherical
portion 433 and the second spherical portion 434) of the pocket
hole 43 of the ball retainer 40 have enough space there-between to
receive the lubricating grease under a high-speed rotation.
Thereby, the inner circumferential surface of the pocket hole 43
and the ball 30 can be buffered by the lubricating grease, so that
the pocket holes 43 of the ball retainer 40 do not directly contact
and interfere with the balls 30.
[0038] After the width W2 of the second gap G2 is determined, a
value of the expansion variable r' needs to be determined. The
expansion variable r' refers to the amount of expansion deformation
of a radius of the outer circumferential surface of the ball
retainer 40 generated by the centrifugal force and the vibration
factor when the ball retainer 40 is rotated at a predetermined
allowable rotational speed N, and the expansion variable r' can be
calculated by the following formula: r'=(r2-r1), in which r1 is an
original radius of the ball retainer 40 before rotation, and r2 is
a radius of the ball retainer 40 when the high-speed ball bearing 1
is at the predetermined allowable rotation speed N.
[0039] It should be noted that, the predetermined allowable
rotational speed N is a highest rotational speed that can be
withstood by the high-speed ball bearing 1, and the predetermined
allowable rotational speed N varies with a pitch diameter Dm of the
ball bearing (as shown in FIGS. 2 and 3). That is, the high-speed
ball bearing 1 of the present disclosure can calculate the
expansion variable r' of the ball retainer 40 under a condition
that a product value DmN, obtained by multiplying the pitch
diameter Dm of the high-speed ball bearing 1 and the predetermined
allowable rotation speed N, is 1,600,000. In other words, before
the expansion variable r' is measured or calculated, the product
value range of the predetermined allowable rotation speed N can be
obtained by a relationship formula of Dm.times.N=1,600,000, and
then the expansion variable r' is measured or calculated according
to the product value range of the predetermined allowable
rotational speed N.
[0040] The expansion variable r' of the ball retainer 40 can be
obtained by actual measurement or computer simulation. If the
expansion variable r' is measured by actual measurement, a test
sample of the ball retainer 40 is produced. Next, the test sample
of the ball retainer 40 is assembled with the outer ring 10, the
inner ring 20, and the ball 30 to form a test sample of the
high-speed ball bearing 1. Then, the test sample of the high-speed
ball bearing 1 is tested by being rotated at a predetermined
allowable rotational speed N through a test machine, an actual
outer diameter of the test sample of the ball retainer 40 is
obtained in a high-speed rotation state, and the radius r2 of the
test sample of the ball retainer 40 under a state of high-speed
rotation is measured and obtained. Finally, the radius r2 of the
test sample of the ball retainer 40 is subtracted by the original
radius r1 of the test sample of the ball retainer 40 so as to
obtain the expansion variable r'.
[0041] On the other hand, if the expansion variable r' is
calculated by the computer simulation, the parameters of sizes,
material weights, elastic modulus of the ball retainer 40, and
diameters and numbers of the balls 30 are input into a simulation
software, and the expansion variable r' of the ball retainer 40
when under high-speed rotation at the predetermined allowable
rotational speed N can be calculated.
[0042] When the width W2 of the second gap G2 is determined and the
expansion variable r' of the ball retainer 40 is calculated, the
width W1 of the first gap G1 between the outer circumferential
surface of the ball retainer 40 and the inner circumferential
surface of the outer ring shoulder 12 can be calculated according
to the formula of W2=(W1-r.sup.-).times.A. Then, a diameter of the
inner circumferential surface of the outer ring shoulder 12 is
subtracted by the width W1 of the first gap G1 so as to obtain a
diameter of the outer circumferential surface of the ball retainer
40. Specifically, in the formula, A is an amplification factor, and
when a product value DmN obtained by multiplying the pitch diameter
Dm of the high-speed ball bearing and a predetermined allowable
rotation speed N is 1,600,000, the amplification factor A is within
a range of 1.2 to 1.5, and the amplification factor A is preferably
1.4.
[0043] According to the above description, a diameter of the outer
circumferential surface of the ball retainer 40 of the present
disclosure can be determined, and a width of the first gap G1
between the outer circumferential surface of the ball retainer 40
and the inner circumferential surface of the outer ring shoulder 12
can be determined, so that the diameter of the outer
circumferential surface of the ball retainer 40 can be formed with
an optimum size for achieving a state of dynamic equilibrium.
[0044] It should be noted that, the ball retainer 40 of the present
disclosure being in the state of dynamic equilibrium under
high-speed rotation means that when the high-speed ball bearing 1
is rotated at a high rotational speed and the ball retainer 40 is
rotated together with the balls 30, the ball retainer 40 can be
suspended at a position between the inner circumferential surface
of the outer ring 10 and the outer circumferential surface of the
inner ring 20. The ball retainer 40 can achieve the state of
dynamic equilibrium by reasons described as follows. When the balls
30 drive the ball retainer 40 to rotate around the central axis of
the ball bearing 1, the ball retainer 40 may bounce in unspecified
directions with respect to the inner circumferential surface of the
outer ring 10. However, when the rotational speed of the ball
bearing 1 is increased, the bounce frequency of the ball retainer
40 with respect to the inner circumferential surface of the outer
ring 10 will be increased, and the diameter of the outer
circumferential surface of the ball retainer 40 will become larger.
Moreover, when the ball bearing 1 is rotated at a high speed, the
width of the first gap G1 within the inner circumferential surface
of the outer ring shoulder 12 is reduced. Therefore, when the ball
bearing 1 is in a state of high rotational speed, the ball retainer
40 will have an intense and rapid bounce frequency within the inner
circumferential surface of the outer ring 10, so that the ball
retainer 40 can be stably suspended between the inner
circumferential surface of the outer ring 10 and the outer
circumferential surface of the inner ring 20 to achieve the state
of dynamic equilibrium.
[0045] In conclusion, the advantages of the present disclosure are
described as follows. A ball retainer 40 having a special design is
disposed in the high-speed ball bearing 1 of the present
disclosure, and when the high-speed ball bearing 1 is rotated at a
high speed, the balls 30 and the inner circumferential surface of
the pocket holes 43 of the ball retainer 40 have enough space
there-between to receive the lubricating grease, the ball retainer
40 can be suspended at a position between the inner circumferential
surface of the outer ring 10 and the outer circumferential surface
of the inner ring 20. Thereby, an interference of the ball 30
affected by the ball retainer 40 during high-speed rotation can be
effectively reduced, and a deflection of the ball retainer 40 can
be effectively avoided, such that the stability of the high-speed
ball bearing 1 can be effectively improved.
[0046] The foregoing description of the exemplary embodiments of
the disclosure has been presented only for the purposes of
illustration and description and is not intended to be exhaustive
or to limit the disclosure to the precise forms disclosed. Many
modifications and variations are possible in light of the above
teaching.
[0047] The embodiments were chosen and described in order to
explain the principles of the disclosure and their practical
application so as to enable others skilled in the art to utilize
the disclosure and various embodiments and with various
modifications as are suited to the particular use contemplated.
Alternative embodiments will become apparent to those skilled in
the art to which the present disclosure pertains without departing
from its spirit and scope.
* * * * *