U.S. patent application number 09/964322 was filed with the patent office on 2003-04-03 for supporting structure for a rotor.
This patent application is currently assigned to Sunonwealth Electric Machine Industry Co., Ltd.. Invention is credited to Hong, Ching-Shen, Horng, Alex.
Application Number | 20030062783 09/964322 |
Document ID | / |
Family ID | 27219625 |
Filed Date | 2003-04-03 |
United States Patent
Application |
20030062783 |
Kind Code |
A1 |
Horng, Alex ; et
al. |
April 3, 2003 |
SUPPORTING STRUCTURE FOR A ROTOR
Abstract
A supporting structure for a rotor comprises two holding
members, a supporting member, and a fixing member that is fixed in
place. Each holding member comprises a hole and an inner flange
formed on an inner periphery defining the hole. The supporting
member comprises a supporting portion and the fixing member has a
hole. An end of a shaft of a rotor extends through the holes of the
fixing members with an end face of the shaft resting on the
supporting portion of the supporting member. A retainer is engaged
in a retaining groove of the shaft to thereby retain the shaft in
place. The shaft and the inner flanges of the holding members have
a minimum gap or a slight contact therebetween.
Inventors: |
Horng, Alex; (Kaohsiung,
TW) ; Hong, Ching-Shen; (Kaohsiung, TW) |
Correspondence
Address: |
Bacon & Thomas
4th Floor
625 Slaters Lane
Alexandria
VA
22314
US
|
Assignee: |
Sunonwealth Electric Machine
Industry Co., Ltd.
Kaohsiung
TW
|
Family ID: |
27219625 |
Appl. No.: |
09/964322 |
Filed: |
September 28, 2001 |
Current U.S.
Class: |
310/91 |
Current CPC
Class: |
F16C 17/08 20130101;
H02K 5/1675 20130101; H02K 7/09 20130101 |
Class at
Publication: |
310/91 |
International
Class: |
H02K 005/00 |
Claims
What is claimed is:
1. A combination of a rotor and a supporting structure for the
rotor, the combination comprising: a metal axle tube; two holding
members mounted in the metal axle tube, each said holding member
comprising a hole, an inner periphery defining the hole having an
inner flange formed thereon; a supporting member mounted in the
metal axle tube and comprising a supporting portion; and a rotor
having a shaft provided to a center thereof, the shaft extending
through the holes of the holding members and comprising a distal
end rotatably resting on the supporting portion of the supporting
member, the shaft and the inner flanges of the holding members
having a minimum gap or a slight contact between.
2. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 1, further comprising a fixing member
securely mounted in the metal axle tube, the fixing member having a
hole defined by a periphery, the shaft comprising an engaging
groove for securely receiving the periphery defining the hole of
the fixing member.
3. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 2, wherein the holding members, the
supporting member, and the fixing member are tightly engaged with
an inner periphery of the metal axle tube.
4. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 3, wherein the holding members and the
supporting member are tightly engaged with the inner periphery of
the metal axle tube, the fixing member being sandwiched by the
supporting member and one of the holding members.
5. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 1, wherein the holding members are
formed as a tubular member having the inner flanges, the integral
holding member being directly tightened to the inner periphery of
the metal axle tube.
6. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 1, wherein the holding members are
integral with each other.
7. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 5, wherein the holding members are
integral with each other.
8. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 1, wherein the metal axle tube is
mounted on a base, a balancing sheet being mounted on the base and
made of a magnetically conductive material, the rotor comprising a
permanent magnet for mutual attraction with the balancing
sheet.
9. A combination of a rotor and a supporting structure for the
rotor, the combination comprising: a metal axle tube; a holding
member mounted in the metal axle tube, the holding member
comprising a hole, an inner periphery defining the hole having an
inner flange formed thereon; a supporting member mounted in the
metal axle tube and comprising a supporting portion; and a rotor
having a central bulge, a shaft having an end securely attached to
the central bulge, the central bulge forming an auxiliary holding
member, the shaft extending through the hole of the holding member
and comprising a distal end rotatably resting on the supporting
portion of the supporting member, the auxiliary holding member and
an inner periphery of the metal axle tube having a minimum gap or a
slight contact between, shaft and the inner flange of the holding
member having a minimum gap or a slight contact between.
10. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 9, further comprising a fixing member
securely mounted in the metal axle tube, the fixing member having a
hole defined by a periphery, the shaft comprising an engaging
groove for securely receiving the periphery defining the hole of
the fixing member.
11. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 9, wherein the metal axle tube is
mounted on a base, a balancing sheet being mounted on the base and
made of a magnetically conductive material, the rotor comprising a
permanent magnet for mutual attraction with the balancing
sheet.
12. A combination of a rotor and a supporting structure for the
rotor, the combination comprising: a metal axle tube; a holding
member mounted in the metal axle tube, the holding member
comprising a hole, an inner periphery defining the hole having an
inner flange formed thereon; a supporting member mounted in the
metal axle tube and comprising a supporting portion; and a rotor
having a shaft provided to a center thereof, an auxiliary holding
member being mounted to the shaft, the shaft extending through the
hole of the holding member and comprising a distal end rotatably
resting on the supporting portion of the supporting member, the
auxiliary holding member of the shaft and an inner periphery of the
metal axle tube having a minimum gap or a slight contact between,
shaft and the inner flange of the holding member having a minimum
gap or a slight contact between.
13. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 12, further comprising a fixing member
securely mounted in the metal axle tube, the fixing member having a
hole defined by a periphery, the shaft comprising an engaging
groove for securely receiving the periphery defining the hole of
the fixing member.
14. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 12, wherein the auxiliary holding member
is made of one of rubber and plastic material.
15. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 12, wherein the shaft comprises an
annular groove for mounting the auxiliary holding member.
16. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 12, wherein the metal axle tube is
mounted on a base, a balancing sheet being mounted on the base and
made of a magnetically conductive material, the rotor comprising a
permanent magnet for mutual attraction with the balancing
sheet.
17. A combination of a rotor and a supporting structure for the
rotor, the combination comprising: a metal axle tube; supporting
member mounted in the metal axle tube and comprising a supporting
portion; and a rotor having a shaft provided to a center thereof,
two auxiliary holding members being mounted to the shaft, the shaft
comprising a distal end rotatably resting on the supporting portion
of the supporting member, the auxiliary holding members of the
shaft and an inner periphery of the metal axle tube having a
minimum gap or a slight contact between.
18. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 17, further comprising a fixing member
securely mounted in the metal axle tube, the fixing member having a
hole defined by a periphery, the shaft comprising an engaging
groove for securely receiving the periphery defining the hole of
the fixing member.
19. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 17, wherein the auxiliary holding member
is made of one of rubber and plastic material.
20. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 17, wherein the shaft comprises two
annular grooves for mounting the auxiliary holding members,
respectively.
21. The combination of a rotor and a supporting structure for the
rotor, as claimed in claim 17, wherein the metal axle tube is
mounted on a base, a balancing sheet being mounted on the base and
made of a magnetically conductive material, the rotor comprising a
permanent magnet for mutual attraction with the balancing sheet.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a supporting structure for
a rotor, wherein at least one holding member is provided for
rotatably supporting the shaft of the rotor in the axle tube in a
minimum deviation, such that the shaft of the rotor rotates stably
and unskewly since the starting moment.
[0003] 2. Description of the Related Art
[0004] Applicant U.S. patent application Ser. No. 09/824,725 filed
on Apr. 4, 2001 and entitled UPPORTING STRUCTURE FOR A ROTOR
discloses a supporting structure comprising a metal axle tube, a
holding member securely mounted in the axle tube, a supporting
member securely mounted in the axle tube and having a supporting
portion, and a fixing member securely mounted in the axle tube and
having an opening. The holding member includes a hole and an inner
flange is formed on an inner periphery defining the hole. A shaft
is provided to a center of the rotor and includes an engaging
groove. The shaft is extended through the hole of the holding
member and the opening of the fixing member with an end face of a
distal end of the shaft rotatably resting on the supporting portion
of the support member and with the fixing member engaging with the
engaging groove of the shaft, whereby the shaft and the inner
flange of the holding member have a slight contact
therebetween.
[0005] Applicant U.S. patent application Ser. No. 09/848,316 filed
on May 4, 2001 and entitled UPPORTING STRUCTURE FOR A ROTOR OF A
MOTOR discloses a combination of a rotor and a supporting structure
for the rotor. The combination comprises an axle, a fixing member
securely mounted in the axle tube, a supporting member securely
mounted in a lower end of the axle tube, and a rotor having a shaft
base and a shaft extending from the shaft base. The shaft includes
an engaging groove. The shaft is extended through the fixing member
with an end face of a distal end of the shaft rotatably resting on
the supporting member and with the fixing member engaging with the
engaging groove of the shaft. The shaft further includes an
auxiliary supporting section, the auxiliary supporting section and
an inner periphery of the axle tube having a minimal gap
therebetween.
[0006] However when the shaft of the rotor rests in the axle tube,
the shaft is merely supported by the flange at one point such that
the central axis of the shaft might be deviated from the central
axis of the axle tube. As a result, larger wobbling and larger
friction occur at the starting moment of the shaft.
SUMMARY OF THE INVENTION
[0007] The primary object of the present invention is to provide a
supporting structure for a rotor, wherein the shaft of the rotor
and at least one holding member have a smaller contact area
therebetween before rotation, thereby providing a more stable
rotation at the starting moment of the shaft.
[0008] Another object of the present invention is to provide a
supporting structure for a rotor, wherein the rotor rotates stably
and thus has a prolonged life while the rotational noise is
reduced.
[0009] A supporting structure for a rotor in accordance with the
present invention comprises two holding members, a supporting
member, and a fixing member that is fixed in place. Each holding
member comprises a hole and an inner flange formed on an inner
periphery defining the hole. The supporting member comprises a
supporting portion and the fixing member has a hole. An end of a
shaft of a rotor extends through the holes of the fixing members
with an end face of the shaft resting on the supporting portion of
the supporting member. A retainer is engaged in a retaining groove
of the shaft to thereby retain the shaft in place. The shaft and
the inner flanges of the holding members have a minimum gap or a
slight contact therebetween.
[0010] Other objects, specific advantages, and novel features of
the invention will become more apparent from the following detailed
description and preferable embodiments when taken in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is an exploded perspective view of a first embodiment
of a supporting structure for a rotor in accordance with the
present invention.
[0012] FIG. 2 is a sectional view of the supporting structure for a
rotor in FIG. 1.
[0013] FIG. 3 is an enlarged view of an ellipse in FIG. 2.
[0014] FIG. 4 is a sectional view similar to FIG. 3, illustrating a
second embodiment of the supporting structure for a rotor in
accordance with the present invention.
[0015] FIG. 5 is a sectional view similar to FIG. 3, illustrating a
third embodiment of the supporting structure for a rotor in
accordance with the present invention.
[0016] FIG. 6 is a sectional view similar to FIG. 3, illustrating a
fourth embodiment of the supporting structure for a rotor in
accordance with the present invention.
[0017] FIG. 7 is a sectional view similar to FIG. 3, illustrating a
fifth embodiment of the supporting structure for a rotor in
accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] Preferred embodiments in accordance with the present
invention will now be described with reference to the accompanying
drawings.
[0019] Referring to FIGS. 1 and 2, a first embodiment in accordance
with the present invention generally comprises a base 1, a metal
axle tube 2, and a rotor 3.
[0020] The base 1 may be a conventional casing for motors or
heat-dissipating fans. In this preferred embodiment, the base 1 may
further comprises a fixed balancing sheet 11 made of a magnetically
conductive material for mutual attraction with a permanent magnet
33 of the rotor 3.
[0021] The metal axle tube 2 is made of a magnetically conductive
material and has an end fixed to the base 1. A conventional stator
bobbin 12 is mounted to the other end of the metal axle tube 2. In
addition, the other end of the metal axle tube 2 may have a flange
20 formed thereon for preventing disengagement of the stator bobbin
12. Mounted in the metal axle tube 2 are a first holding member 21,
a second holding member 22, a supporting member 23, and a fixing
member 24 that can be secured to an inner periphery of the metal
axle tube 2 by any fixing means. The first holding member 21 is
tightly engaged with the inner periphery of the metal axle tube 2
by force-fitting. The second holding member 23 and the supporting
member 23 may also be tightly engaged with the inner periphery of
the metal axle tube 2 by force-fitting, and the second holding
member 22 and the supporting member 23 sandwiches the fixing member
24, which is a simple method for mounting these members.
[0022] Each of the first holding member 21 and the second holding
member 22 has a hole 211, 221 through which a shaft 31 of the rotor
3 extends. Preferably, the shaft 31 has a minimum contact area with
the first holding member 21 and the second holding member 22. As
illustrated in FIG. 2, an inner flange 212 is formed on an inner
periphery defining the hole 211 of the first holding member 21 and
an inner flange 222 is formed on an inner periphery defining the
hole 221 of the second holding member 22.
[0023] The supporting member 23 comprises a supporting portion 230
that may be a closed bottom side of the supporting member 23.
Alternatively, as illustrated in FIGS. 1 and 2, the supporting
member 23 has a hole 231 and a supporting plate 232 for covering
the hole 231. A distal end of the shaft 31 of the rotor 3 rests on
the supporting portion 230 or the supporting plate 232. The fixing
member 24 may be a conventional retaining ring and is fixed in the
metal axle tube 2 at an appropriate location. In addition, the
fixing member 24 comprises a hole 241, a periphery defining the
hole 241 being deformable to allow easy passage of the shaft 31 of
the rotor 3.
[0024] The shaft 31 is mounted to a central portion of the rotor 3.
The shaft 31 extends through the hole 211 of the first holding
member 2, the hole 221 of the second holding member 22, and the
hole 241 of the fixing member 24 with the distal end of the shaft
31 resting on the supporting portion 230 or the supporting plate 23
of the supporting member 23. In addition, the shaft 31 has a
retaining groove 32 for securely receiving the periphery defining
the hole 241 of the fixing member 24 to thereby prevent
disengagement of the rotor 3. The shaft 31 and the inner flanges
212 and 222 of the first and second holding members 21 and 22 have
a minimum gap or a slight contact therebetween, best shown in FIG.
3. A permanent magnet 33 is mounted to the rotor 3 for induction
with the stator bobbin 12 and for attraction with the balancing
sheet 11.
[0025] FIG. 4 illustrates a second embodiment of the present
invention, wherein the first holding member and the second holding
member are integrally formed to form a single holding member 25
having a hole 251 through which the shaft 31 extends. Two inner
flanges 252 are formed on an inner periphery defining the hole 251
and the shaft 31 have a minimum gap or a slight contact
therebetween. In addition, the inner flanges 252 have an
appropriate space therebetween. Preferably, the inner flanges 252
are respectively formed on two ends of the inner periphery defining
the hole 251. Thus, the holding member 25 may have the smallest
contact area with the shaft 31. In addition, a central axis of the
shaft 31 has the smallest deviation from a central axis of the axle
tube 20 when the shaft 31 is not turned. And rotation of the shaft
31 becomes stable immediately after it is turned.
[0026] FIG. 5 illustrates a third embodiment of the present
invention, wherein the only one holding member 22 is mounted in the
metal axle tube 2. The holding member 22 has a hole 221 through
which the shaft 31 extends. An inner flange 222 is formed on an
inner periphery defining the hole 221. The inner flange 222 and the
shaft 31 have a minimum gap or a slight contact therebetween. An
end of the shaft 31 is mounted to a central bulge 34 of the rotor
3. The central bulge 34 of the rotor 3 has a diameter slightly
smaller than an inner diameter of the metal axle tube 2 such that
the central bulge 34 and the inner periphery of the metal axle tube
2 have a minimum gap or a slight contact therebetween. Thus, the
central bulge 34 of the rotor 3 also provides a holding function
and cooperates with the holding member 22 to rotatably hold the
shaft 31 such that the central axis of the shaft 31 has the
smallest deviation from the central axis of the axle tube 20 when
the shaft 31 is not turned.
[0027] FIG. 6 illustrates a fourth embodiment of the present
invention, wherein only one holding member 22 is mounted in the
metal axle tube 2. The holding member 22 has a hole 221 through
which the shaft 31 extends. An inner flange 222 is formed on an
inner periphery defining the hole 221. The inner flange 222 and the
shaft 31 have a minimum gap or a slight contact therebetween. An
auxiliary holding member 35 made of rubber or plastic material is
mounted around the shaft 31. As illustrated in FIG. 6, the shaft 31
may include an annular groove for securely receiving the auxiliary
holding member 35. The auxiliary holding member 35 has a diameter
slightly smaller than an inner diameter of the metal axle tube 2
such that the auxiliary holding member 35 and the inner periphery
of the metal axle tube 2 have a minimum gap or a slight contact
therebetween. Thus, the auxiliary holding member 35 also provides a
holding function and cooperates with the holding member 22 to
rotatably hold the shaft 31 such that the central axis of the shaft
31 has the smallest deviation from the central axis of the axle
tube 20 when the shaft 31 is not turned.
[0028] FIG. 7 illustrates a fifth embodiment of the invention,
wherein two auxiliary holding members 35a and 35b made of rubber or
plastic material are mounted around the shaft 31. The auxiliary
holding members 35a and 35b are securely mounted around the shaft
31. Each auxiliary holding member 35a, 35b has a diameter slightly
smaller than an inner diameter of the metal axle tube 2 such that
the auxiliary holding members 35a and 35b and the inner periphery
of the metal axle tube 2 have a minimum gap or a slight contact
therebetween. Thus, the auxiliary holding members 35 together
provide a holding function for rotatably holding the shaft 31 such
that the central axis of the shaft 31 has the smallest deviation
from the central axis of the axle tube 20 when the shaft 31 is not
turned.
[0029] By means of provision of the supporting structure for a
rotor in accordance with the present invention, the shaft 31 of the
rotor 3 is merely supported by the supporting portion 230 or the
supporting plate 232 of the supporting member 23 at the distal end
thereof. In addition, the shaft 31 and the inner periphery of the
metal axle tube 2 have a minimum gap or a slight contact
therebetween by means of provision of the auxiliary holding
member(s) 35 or the central bulge 34. Alternatively, the two
holding members 21 and 22 and the shaft 31 have a minimum gap or a
slight contact therebetween such that the central axis of the shaft
31 has the smallest deviation from the central axis of the axle
tube 20 when the shaft 31 is not turned. And rotation of the shaft
31 becomes stable immediately after it is turned. Accordingly, the
rotational friction and rotational noise of the shaft 31 can be
reduced to the least condition. Furthermore, the rotor 3 can be
processed and manufactured easily and the assembling procedure of
the rotor 3 is simple, thereby reducing the manufacture cost.
[0030] Although the invention has been explained in relation to its
preferred embodiment as mentioned above, it is to be understood
that many other possible modifications and variations can be made
without departing from the scope of the invention. It is,
therefore, contemplated that the appended claims will cover such
modifications and variations that fall within the true scope of the
invention.
* * * * *