U.S. patent number RE46,265 [Application Number 14/046,669] was granted by the patent office on 2017-01-03 for rotating electric apparatus and method for connecting stator coils thereof.
This patent grant is currently assigned to Hitachi, Ltd.. The grantee listed for this patent is Hitachi, Ltd.. Invention is credited to Takashi Ishigami, Kenichi Nakayama, Yasuyuki Saito, Yuichiro Tanaka.
United States Patent |
RE46,265 |
Tanaka , et al. |
January 3, 2017 |
Rotating electric apparatus and method for connecting stator coils
thereof
Abstract
Each pair of coils mutually connected in a stator winding is
arranged in a fashion that a first coil of each pair of coils has
an inner-circumferential-side coil terminal (212) led out from an
inner-circumferential-side slot position in the direction of a coil
end (220) of the stator winding, and that a second coil of each
pair of coils has an outer-circumferential-side coil terminal (211)
led out from an outer-circumferential-side slot position in the
direction of the coil end (220) of the stator winding for
connection to the inner-circumferential-side coil terminal (212),
wherein there is provided a coil terminal connection structure in
which the inner-circumferential-side coil terminal (212) is
connected to the outer-circumferential-side coil terminal (211)
across the coil end (220), and joint parts (211a, 212a) thereof are
bent close to the coil end (220).
Inventors: |
Tanaka; Yuichiro (Hitachinaka,
JP), Ishigami; Takashi (Hitachinaka, JP),
Nakayama; Kenichi (Hitachinaka, JP), Saito;
Yasuyuki (Hitachinaka, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Hitachi, Ltd. |
Chiyoda-ku, Tokyo |
N/A |
JP |
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Assignee: |
Hitachi, Ltd. (Tokyo,
JP)
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Family
ID: |
1000001797789 |
Appl.
No.: |
14/046,669 |
Filed: |
October 4, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
12370307 |
Feb 12, 2009 |
8030812 |
Oct 4, 2011 |
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Foreign Application Priority Data
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Feb 13, 2008 [JP] |
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2008-031517 |
Oct 24, 2008 [JP] |
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2008-274002 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02K
3/28 (20130101); H02K 15/0081 (20130101); H02K
3/12 (20130101); H02K 3/12 (20130101); H02K
15/0081 (20130101); H02K 3/28 (20130101) |
Current International
Class: |
H02K
3/12 (20060101); H02K 3/28 (20060101); H02K
15/00 (20060101) |
Field of
Search: |
;310/71,201,208 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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54-72402 |
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Jun 1979 |
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JP |
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54-121908 |
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Sep 1979 |
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JP |
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10-248187 |
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Sep 1998 |
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JP |
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11-150906 |
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Jun 1999 |
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JP |
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2000-228852 |
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Aug 2000 |
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JP |
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2001-037131 |
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Feb 2001 |
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JP |
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2001-211585 |
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Aug 2001 |
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JP |
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2002-101589 |
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Apr 2002 |
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JP |
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2002-315246 |
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Oct 2002 |
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JP |
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2004-32892 |
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Jan 2004 |
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JP |
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2004-80860 |
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Mar 2004 |
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JP |
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2004-274946 |
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Sep 2004 |
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JP |
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2006-6010 |
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Jan 2006 |
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JP |
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2006-094694 |
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Apr 2006 |
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JP |
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2006-101654 |
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Apr 2006 |
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JP |
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2006-288123 |
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Oct 2006 |
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JP |
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2006-340580 |
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Dec 2006 |
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JP |
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2007-037344 |
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Feb 2007 |
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JP |
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2009-106003 |
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May 2009 |
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JP |
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Primary Examiner: Nguyen; Minh T
Attorney, Agent or Firm: Crowell & Moring LLP
Claims
What is claimed is:
.[.1. A rotating electric apparatus comprising: a stator having a
stator winding comprising a plurality of coils connected in a
plurality of slots formed in a stator iron core; and a rotor
rotatably disposed in the inside of said stator; wherein, each pair
of coils mutually connected in said stator winding is arranged in a
fashion that a first coil of each said pair of coils has a top-side
coil terminal at a top-side position of said slot, said top-side
coil terminal being led out in the direction of a coil end of said
stator winding; and a second coil of each said pair of coils has a
bottom-side coil terminal at a bottom-side position of said slot
said bottom-side coil terminal being led out in the direction of
said coil end of said stator winding for connection to said
top-side coil terminal; there is provided a coil terminal
connection structure in which said top-side coil terminal and said
bottom-side coil terminal are connected mutually across said coil
end, and joint parts of said top-side coil terminal and said
bottom-side coil terminal thus connected are bent so that said
joint parts are disposed close to said coil end; each one of said
top-side coil terminal and said bottom-side coil terminal is laid
spiral-wise across said coil end to a position of the other one of
said top-side and bottom-side coil terminals; side faces of joint
parts of said top-side and bottom-side coil terminals are connected
mutually in a fashion such that end faces of said joint parts of
said top-side and bottom-side coil terminals are oriented in
mutually opposite directions; and said joint parts thus connected
are disposed close to said coil end..].
2. A rotating electric apparatus comprising: a stator having a
stator winding comprising a plurality of coils connected in a
plurality of slots formed in a stator iron core; and a rotor
rotatably disposed in the inside of said stator; wherein, each pair
of coils mutually connected in said stator winding is arranged in a
fashion that a first coil of each said pair of coils has a top-side
coil terminal at a top-side position of said slot, said top-side
coil terminal being led out in the direction of a coil end of said
stator winding; and a second coil of each said pair of coils has a
bottom-side coil terminal at a bottom-side position of said slot,
said bottom-side coil terminal being led out in the direction of
said coil end of said stator winding for connection to said
top-side coil terminal; there is provided a coil terminal
connection structure in which either one of said top-side coil
terminal and said bottom-side coil terminal is extended through a
coil-to-coil clearance on said coil end to a position of the other
one of said top-side and bottom-side coil terminals, and said one
of said top-side and bottom-side coil terminals thus extended is
connected to the other one of said top-side and bottom-side coil
terminals; in a case where said top-side coil terminal is led out
to a position of .[.a.]. .Iadd.said .Iaddend.bottom-side coil
terminal, joint parts of said top-side coil terminal and said
bottom-side coil terminal are bent radially inwardly with respect
to said stator iron core; and in a case where said bottom-side coil
terminal is led out to a position of said top-side coil terminal,
joint parts of said top-side coil terminal and said bottom-side
coil terminal are bent radially outwardly with respect to stator
iron core.
3. A rotating electric apparatus comprising: a stator including a
stator iron core that has a plurality of slots formed thereon, and
a stator winding that comprises a plurality of coils held in said
plurality of slots; and a rotor having a face opposed to a face of
said stator iron core mutually, said rotor being held rotatably via
an air gap so that there is produced a magnetic circuit through
which a magnetic flux is passed between the mutually opposed faces
of said stator iron core and said rotor via said air gap; wherein,
each pair of coils mutually connected in said stator winding is
arranged in a fashion that one of each said pair of coils has a
top-side coil terminal at a top-side position of said slot, said
top-side coil terminal being led out in the direction of a coil end
of said stator winding; and the other one of each said pair of
coils has a bottom-side coil terminal at a bottom-side position of
said slot, said bottom-side coil terminal being led out in the
direction of said coil end of said stator winding for connection to
said top-side coil terminal; either one of said top-side coil
terminal and said bottom-side coil terminal is laid spiral-wise
along said coil end to a position of the other one of said top-side
and bottom-side coil terminals so that said one of said top-side
and bottom-side coil terminals is connected to the other one of
said top-side and bottom-side coil terminals; in a case where said
top-side coil terminal is laid spiral-wise to a position of said
bottom-side coil terminal, joint parts of said top-side coil
terminal and said bottom-side coil terminal are bent radially
inwardly with respect to said stator iron core; and in a case where
said bottom-side coil terminal is laid spiral-wise to a position of
said top-side coil terminal, joint parts of said top-side coil
terminal and said bottom-side coil terminal are bent radially
outwardly with respect to said stator iron core.
4. A rotating electric apparatus as claimed in claim 3, wherein
joint parts of said top-side coil terminal and said bottom-side
coil terminal are bent in a fashion that said joint parts are
folded back to one of said top-side and bottom-side coil terminals
that is laid spiral-wise along said coil end.
5. A rotating electric apparatus comprising: a stator having a
stator winding comprising a plurality of coils connected in a
plurality of slots formed in a stator iron core; and a rotor
rotatably disposed in the inside of said stator; wherein each pair
of coils mutually connected in said stator winding is arranged in a
fashion that, a first coil of each said pair of coils has a
top-side coil terminal at a top-side position of said slot, said
top-side coil terminal being led out in the direction of a coil end
of said stator winding; and a second coil of each said pair of
coils has a bottom-side coil terminal at a bottom-side position of
said slot, said bottom-side coil terminal being led out in the
direction of said coil end of said stator winding for connection to
said top-side coil terminal; wherein one of said top-side coil
terminal and said bottom-side coil terminal is laid spiral-wise
along said coil end of said stator winding, and an opening selected
from a notch and a through hole is formed on a joint part of said
one of said top-side and bottom-side coil terminals, and wherein
the other one of said top-side and bottom-side coil terminals is
bent radially across said coil end, and a joint part of the other
one of said top-side and bottom-side coil terminals is engagedly
connected to said opening formed on said joint part of said one of
said top-side and bottom-side coil terminals.
6. A rotating electric apparatus comprising: a stator having a
stator winding comprising a plurality of coils connected in a
plurality of slots formed in a stator iron core; and a rotor
rotatably disposed in the inside of said stator; wherein each pair
of coils mutually connected in said stator winding is arranged in a
fashion that, a first coil of each said pair of coils has a
top-side coil terminal at a top-side position of said slot, said
top-side coil terminal being led out in the direction of a coil end
of said stator winding; and a second coil has a bottom-side coil
terminal at a bottom-side position of said slot, said bottom-side
coil terminal being led out in the direction of said coil end of
said stator winding for connection to said top-side coil terminal;
wherein said stator winding is formed of a flat-type conductor wire
material having a rectangular cross section, with a wide side face
of said flat-type conductor wire material corresponding to the long
side of said rectangular cross section, and with a narrow side face
of said flat-type conductor wire material corresponding to the long
side of said rectangular cross section, wherein one of said
top-side coil terminal and said bottom-side coil terminal is laid
spiral-wise along said coil end of said stator winding, wherein a
joint part of said one of said top-side and bottom-side coil
terminals is bent radially with respect to said stator, and wherein
the other one of said top-side and bottom-side coil terminals is
bent radially across said coil end .[.so that the wide side face of
the other one of said top-side and bottom-side coil terminals is
connected to the narrow side face of said one of said top-side and
bottom-side terminals.]..
.Iadd.7. The rotating electric apparatus as claimed in claim 6,
wherein both of said top-side coil terminal and said bottom-side
coil terminal are laid spiral-wise along said coil end of said
stator winding..Iaddend.
.Iadd.8. The rotating electric apparatus as claimed in claim 6,
wherein a wide side face of said one of said top-side and
bottom-side coil terminals is connected to a wide side face of said
other one of said top-side and bottom-side coil
terminals..Iaddend.
.Iadd.9. The rotating electric apparatus as claimed in claim 6,
wherein a joint part of said other one of said top-side and
bottom-side coil terminals is bent radially with respect to said
stator..Iaddend.
.Iadd.10. The rotating electric apparatus as claimed in claim 9,
wherein said joint parts of said one of said top-side and
bottom-side coil terminals and said other one of said top-side and
bottom-side coil terminals are bent radially outward..Iaddend.
.Iadd.11. The rotating electric apparatus as claimed in claim 9,
wherein said joint parts of said one of said top-side and
bottom-side coil terminals and said other one of said top-side and
bottom-side coil terminals are arranged outside of said coil
end..Iaddend.
.Iadd.12. The rotating electric apparatus as claimed in claim 9,
wherein edge portions of said joint parts are pointing toward
radially outside..Iaddend.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a rotating electric apparatus such
as a motor or generator, and a method for connecting stator coils
thereof.
2. Description of the Related Art
The types of stator windings are generally classified into a
concentrated winding arrangement and a distributed winding
arrangement; in the former, coils are concentrated per magnetic
pole tooth, and in the latter, coils are provided across a
plurality of slots so that different-phase or same-phase coils are
made to overlap one another at a coil end position. In the
concentrated winding arrangement, although a small coil end of a
stator can be provided which is advantageous for reduction in size
and enhancement in performance of a rotating electric apparatus, a
rotating magnetic field produced on the inner circumference of the
stator is not evenly distributed, thereby bringing about a
disadvantage that noise is prone to occur due to harmonics. By way
of contrast, in the distributed winding arrangement adopted for a
stator in conventional practice, it is generally possible to
restrict a rotating magnetic field produced on the inner
circumference of the stator within a substantially sinusoidal range
for reducing noise to a lower level than that in the concentrated
winding arrangement. However, in the distributed winding
arrangement, since there is a significant extent of overlapping of
coils at a coil end position, the volume of the stator is larger
than that of the concentrated winding arrangement, giving rise to
difficulty in size reduction and performance enhancement of a
rotating electric apparatus.
For example, in the design of a main drive motor for an electric
automobile, it is required to provide a high output by using a
limited battery voltage under a considerably restricted condition
on availability in mounting space. As a means for meeting
requirements for extremely severe levels of compactness and high
output, there is known a technique of increasing a coil space
factor in a stator slot by using a copper element wire having a
substantially rectangular cross section as a coil wire material. In
a concentrated winding type of stator, a copper element wire having
a substantially rectangular cross section is applicable relatively
with ease since the configuration of each coil is rather simple.
Earlier patent disclosures dealing with embodiments in which stator
coils are structured in a concentrated winding form by continuously
providing a copper element wire having a substantially rectangular
cross section are found in patent documents 1 and 2 indicated
below.
In cases where a copper element wire having a substantially
rectangular cross section is used for each stator coil in a
distributed winding form, it is required to circumvent possible
occurrence of mutual interference on element wires while keeping
the element wires in a proper alignment. As a conventional means
for meeting this requirement, there is known a technique of
providing a three-phase coil arrangement in a concentric winding
form as disclosed in patent document 3 indicated below. In the coil
end structure of the three-phase coil arrangement, U-phase, V-phase
and W-phase members are stacked on one another axially without
overlapping thereof, thereby preventing mutual interference on the
members of three different phases. Patent document 1: Japanese
Unexamined Patent Publication No. 2004-80860 Patent document 2:
Japanese Unexamined Patent Publication No. 2006-288123 Patent
document 3: Japanese Unexamined Patent Publication No.
2006-101654
However, since the members of the three phases have different coil
end configurations to prevent mutual interference on the element
wires stacked at a coil end position, there is an inevitable
disadvantage that the size of the entire coil end is rather
large.
It is to be noted that the following aspects of the present
invention concerning the problems to be solved by the present
invention are also applicable to resolution of other problems that
are critical in product manufacturing as will be described
later.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to obviate the
above-mentioned disadvantages by providing a rotating electric
apparatus and a method for connecting stator coils thereof that
enable enhancement in productivity, improvement in performance, and
reduction in size.
According to a first aspect of the present invention, there is
provided a rotating electric apparatus comprising: a stator having
a stator winding comprising a plurality of coils connected in a
plurality of slots formed in a stator iron core; and a rotor
rotatably disposed in the inside of the stator; wherein each pair
of coils mutually connected in the stator winding is arranged in a
fashion that a first coil of each pair of coils has a top-side coil
terminal led out from an inner-circumferential-side slot position
in the direction of a coil end of the stator winding, and that a
second coil of each pair of coils has a bottom-side coil terminal
led out from a bottom-side slot position in the direction of the
coil end of the stator winding for connection to the top-side coil
terminal; and wherein a coil terminal connection structure is
provided in which the top-side coil terminal and the bottom-side
coil terminal are connected mutually across the coil end, and in
which joint parts of the top-side coil terminal and the bottom-side
coil terminal thus connected are bent so that the joint parts are
disposed close to the coil end.
According to a second aspect of the present invention, there is
provided a rotating electric apparatus comprising: a stator having
a stator winding comprising a plurality of coils connected in a
plurality of slots formed in a stator iron core; and a rotor
rotatably disposed in the inside of the stator; wherein each pair
of coils mutually connected in the stator winding is arranged in a
fashion that a first coil of each pair of coils has a top-side coil
terminal led out from a top-side slot position in the direction of
a coil end of the stator winding, and that a second coil of each
pair of coils has a bottom-side coil terminal led out from a
bottom-side slot position in the direction of the coil end of the
stator winding for connection to the top-side coil terminal;
wherein a coil terminal connection structure is provided in which
either one of the top-side coil terminal and the bottom-side coil
terminal is extended through a coil-to-coil clearance on the coil
end to a position of the other one of the top-side and bottom-side
coil terminals, and the one of the top-side and bottom-side coil
terminals thus extended is connected to the other one of the
top-side and bottom-side coil terminals.
According to a third aspect of the present invention, there is
provided a rotating electric apparatus comprising: a stator
including a stator iron core that has a plurality of slots formed
thereon, and a stator winding that comprises a plurality of coils
held in the plurality of slots; and a rotor having a face opposed
to a face of the stator iron core mutually, the rotor being held
rotatably via an air gap so that a magnetic circuit is produced
through which a magnetic flux is passed between the mutually
opposed faces of the stator iron core and the rotor via the air
gap; wherein each pair of coils mutually connected in the stator
winding is arranged in a fashion that one of each pair of coils has
a top-side coil terminal led out from a top-side slot position in
the direction of a coil end of the stator winding, and that the
other one of each pair of coils has a bottom-side coil terminal led
out from a bottom-side slot position in the direction of the coil
end of the stator winding for connection to the top-side coil
terminal; and wherein either one of the top-side coil terminal and
the bottom-side coil terminal is laid spiral-wise along the coil
end to a position of the other one of the top-side and bottom-side
coil terminals so that the one of the top-side and bottom-side coil
terminals is connected to the other one of the top-side and
bottom-side coil terminals.
According to a fourth aspect of the present invention, there is
provided a rotating electric apparatus comprising: a stator having
a stator winding comprising a plurality of coils connected in a
plurality of slots formed in a stator iron core; and a rotor
rotatably disposed in the inside of the stator; wherein each pair
of coils mutually connected in the stator winding is arranged in a
fashion that a first coil of each pair of coils has a top-side coil
terminal led out from a top-side slot position in the direction of
a coil end of the stator winding, and that a second coil of each
pair of coils has a bottom-side coil terminal led out from a
bottom-side slot position in the direction of the coil end of the
stator winding for connection to the top-side coil terminal;
wherein one of the top-side coil terminal and the bottom-side coil
terminal is laid spiral-wise along the coil end of the stator
winding, and an opening selected from a notch and a through hole is
formed on a joint part of the one of the top-side and bottom-side
coil terminals, and wherein the other one of the top-side and
bottom-side coil terminals is bent radially across the coil end,
and a joint part of the other one of the top-side and bottom-side
coil terminals is engagedly connected to the opening formed on the
joint part of the one of the top-side and bottom-side coil
terminals.
According to a fifth aspect of the present invention, there is
provided a relating electric apparatus comprising: a stator having
a stator winding comprising a plurality of coils connected in a
plurality of slots formed in a stator iron core; and a rotor
rotatably disposed in the inside of the stator; wherein each pair
of coils mutually connected in the stator winding is arranged in a
fashion that a first coil of each pair of coils has a top-side coil
terminal fed out from a top-side slot position in the direction of
a coil end of the stator winding, and that a second coil has a
bottom-side coil terminal led out from a bottom-side slot position
in the direction of the coil end of the stator winding for
connection to the top-side coil terminal, wherein the stator
winding is formed of a flat-type conductor wire material having a
rectangular cross section, with a wide side face of the flat-type
conductor wire material corresponding to the long side of the
rectangular cross section, and with a narrow side face of the
flat-type conductor wire material corresponding to the long side of
the rectangular cross section, wherein one of the top-side coil
terminal and the bottom-side coil terminal is laid spiral-wise
along the coil end of the stator winding, wherein a joint part of
the one of the top-side and bottom-side coil terminals is bent
radially with respect to the stator, and wherein the other one of
the top-side and bottom-side coil terminals is bent radially across
the coil end so that the wide side face of the other one of the
top-side and bottom-side coil terminals is connected to the narrow
side face of the one of the top-side and bottom-side terminals.
According to a sixth aspect of the present invention, there is
provided a coil connecting method for connecting stator coils of a
rotating electric apparatus that comprises a stator having a stator
winding including a plurality of coils connected in a plurality of
slots formed in a stator iron core, and a rotor rotatably disposed
in the inside of the stator, the coil connecting method comprising
the steps of: providing a winding-around form of coil wire in a
first pair of the slots, leading out a first coil terminal from a
top-side position of the first pair of the slots in the direction
of a coil end of the stator winding, providing a winding-around
form of coil wire in a second pair of the slots, leading out a
second coil terminal from a bottom-side position of the second pair
of the slots in the direction of the coil end of the stator
winding, and connecting the first coil terminal and the second coil
terminal mutually across the coil end of the stator winding.
In accordance with the above-mentioned aspects of the present
invention, it is possible to decrease a total coil height in a
stator of a rotating electric apparatus for realizing reduction in
size of the entire coil end.
As regards the following preferred embodiments of the present
invention, it is to be understood that besides providing the
above-mentioned advantageous features, the present invention can
also solve other problems described below and provide advantageous
effects as stated below. The problems and advantageous effects
mentioned in the following description are of critical importance
in product manufacturing. The preferred embodiments described below
are based on deliberate examinations that have been conducted by
the inventors of the present invention for the purpose of product
commercialization, i.e., according to the present invention, it is
possible to solve various critical problems and provide
advantageous effects with respect to product commercialization in
addition to the above-mentioned reduction of coil end size. These
problems to be solved and the advantageous effects to be provided
are treated hereinbelow.
The above and other objects, features and advantages of the present
invention will become more apparent from the following detailed
description with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional side view showing an induction-type rotating
electric apparatus in a preferred embodiment of the present
invention;
FIG. 2 is a sectional view showing a stator of the induction-type
rotating electric apparatus;
FIG. 3 is a perspective view showing a cross section of a rotor of
the induction-type rotating electric apparatus;
FIG. 4 is a connection diagram of a stator coil 413 formed in 2Y
connection;
FIG. 5 is a detailed diagram of coils U11 and U12, showing an
arrangement before joint connection in (a), and an arrangement
after joint connection in (b);
FIG. 6 is a diagram showing a positional relationship of slots 411
and coil parts constituting the stator coil 413;
FIG. 7 is a perspective view showing coils formed in a stator iron
core 412 before joint connection;
FIGS. 8(a)-8(d) are diagrams showing a first connection structure
of conductor terminals 211 and 212;
FIGS. 9(a)-9(d) are explanatory diagrams of a second connection
structure of the conductor terminals 211 and 212;
FIGS. 10(a)-10(c) are explanatory diagrams showing a third
connection structure of the conductor terminals 211 and 212;
FIGS. 11(a)-11(b) are explanatory diagrams showing a fourth
connection structure of the conductor terminals 211 and 212;
FIGS. 12(a)-12(b) are explanatory diagrams showing a fifth
connection structure of the conductor terminals 211 and 212;
FIGS. 13(a)-13(b) are explanatory diagrams showing a sixth
connection structure of the conductor terminals 211 and 212;
FIGS. 14(a)-14(b) are explanatory diagrams showing a seventh
connection structure of the conductor terminals 211 and 212;
FIG. 15 is a diagram showing an exemplary modified form of the
seventh connection structure;
FIGS. 16(a)-16(b) are explanatory diagrams showing an eighth
connection structure of the conductor terminals 211 and 212;
and
FIGS. 17(a)-17(b) are diagrams of exemplary modified forms of the
eighth connection structure, showing a first modified form in FIG.
17(a), and a second modified form in FIG. 17(b).
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described in detail by way of
example with reference to the accompanying drawings. The following
preferred embodiments of the present invention are applicable to
resolution of the problems described below and provision of the
advantageous effects mentioned below. Most of these problems to be
solved and advantageous effects to be provided are different from
those mentioned in the foregoing description though duplications in
some aspects are included.
Enhancement in Productivity:
In the following preferred embodiments of the present invention, a
coil formed of a single turn or plural turns of conductor wire as
shown in FIG. 5 is used for a stator. Each coil comprises two
insertion parts including a first insertion part and a second
insertion part, for insertion into slots; and two coil ends
including a first coil end and a second coil end, for connection of
the first and second insertion parts. As illustrated in FIGS. 6 to
7, in a case where a first insertion part of a first coil is
disposed at a depth position (bottom-side position) of a first slot
for example, a second insertion part of the first coil is disposed
at an opening position (top-side position) of a second slot. At an
opening position (top-side position) of the first slot where the
first insertion part of the first coil is disposed, there is
located a second insertion part of a second coil. Further, at the
depth position (bottom-side position) of the second slot where the
second insertion part of the first coil is disposed, there is
located a first insertion part of a third coil. In such a
positional relationship of slots as mentioned above, a plurality of
coils constituting a three-phase stator winding are arranged along
the entire circumference of a stator structure.
Since each of the coils is made of a continuous conductor, there is
no need to perform welding for connecting first and second
insertion parts of each coil, for example, in coil formation.
Hence, according to the preferred embodiments of the present
invention, it is possible to enhance productivity of coils. In the
preferred embodiments, the number of connection points is
relatively small with respect to the entire structure of the stator
winding, contributing to enhancement in productivity.
Further, as shown in FIGS. 5 and 6, there is provided a structural
arrangement in which two coils to be used as a pair are allocated
in adjacent slots, thereby allowing the formation of a pair of
coils by using a continuous conductor. This structural arrangement
can decrease the number of connection points in the entire stator
structure, allowing enhancement in productivity. A decrease in the
number of connection points leads to improvement in electrical
characteristics to enable further reduction in size.
As shown in FIG. 5 and FIGS. 7 to 13, since joint parts of
conductor terminals (indicated by reference numerals 211a and 212a,
for example, in the drawing figures) are located at outside
positions of first and second coil ends, it is rather easy to
perform connection work in coil formation, resulting in an increase
in productivity. Further, the entire stator structure is simplified
to contribute to further reduction in size and improvement in
reliability.
Moreover, joint parts of the conductor terminals are disposed on
one side only at first and second coil ends in coil formation,
contributing to improvement in productivity.
Improvement in Performance:
Each coil having first and second insertion parts is formed by
providing a single turn or plural turns of conductor wire. By
changing the number of wire turns, it is allowed to adjust the
number of conductor layers stacked in the direction from an opening
slot position to a depth slot position (in the radial direction of
the rotating electric apparatus). More specifically, since there is
provided a structural arrangement in which a first insertion part
of each coil formed of a single turn or plural turns of conductor
wire is disposed at a depth slot position (bottom-side slot
position) and a second insertion part thereof is disposed at an
opening slot position (top-side slot position), the number of
conductor layers stacked in each slot can be adjusted as required
in accordance with the number of wire turns meeting particular
requirements for electrical characteristics. The structural
arrangement mentioned above makes it possible to facilitate the
provision of a rotating electrical apparatus having electrical
characteristics suitable for particular application. It is to be
noted that the above-mentioned structural disposition of coils is
not disclosed in the patent documents 1 to 3 cited in the foregoing
section BACKGROUND OF THE INVENTION.
As shown in FIGS. 5 and 6, there is provided a structural
arrangement in which each same-phase part or each coil part
corresponding to the same phase (e.g., U11, or each of U12, V11,
and V12) comprises a plurality of coils, which are allocated in
adjacent slots. In the plurality of coils allocated in the adjacent
slots, a first insertion part of each coil is disposed at a depth
slot position (bottom-side slot position), and a second insertion
part thereof is disposed at an opening slot position (top-side slot
position), thereby making it possible to improve performance as
well as enhance productivity.
Reduction in Size:
While the present invention has been described with respect to
reduction in size in the foregoing, the following aspects of the
present invention can also lead to significant contribution to the
realization of reduction in size of a rotating electric
apparatus.
As shown in FIGS. 5 to 7, there is provided a structural
arrangement in which each coil formed of a single turn or plural
turns of conductor wire is used, the coil comprises first and
second insertion parts for insertion into slots, and first and
second coil ends for connection of the first and second insertion
parts, and the coil is made of a continuous conductor. Since such a
process as welding is not required for connection between the first
and second insertion parts, the size of the coil itself can be
decreased for size reduction of the stator, contributing to size
reduction of the entire structure of a rotor.
Since a first insertion part of each coil is disposed at a depth
slot position and a second insertion part thereof is disposed at an
opening slot position, it is allowed to carry out coil formation by
using a conductor having a substantially rectangular cross section.
Accordingly, conductor layers can be stacked in the short side
direction with respect to the substantially rectangular cross
section of the conductor. The use of a conductor having a
substantially rectangular cross section makes it possible to
improve performance, and further by stacking conductor layers in
the short side direction with respect to the substantially
rectangular cross section of the conductor, i.e., by stacking
conductor layer so that the long sides of the substantially
rectangular cross sections of the conductor layers are arranged to
face mutually, the size of the stator can be made smaller for
reduction in size of the entire structure of the rotating electric
apparatus.
With reference to the accompanying drawings, the following
describes the best modes for carrying out the present invention,
taking an induction-type rotating electric apparatus as an example.
This type of rotating electric apparatus, which is adopted for a
drive system of a hybrid automobile or the like, provides a drive
motor function for wheel driving and a generator function for
generating electricity. The induction-type rotating electric
apparatus is used for stating an internal combustion engine from a
stopped state, generating a partial motive torque power for vehicle
running in combination with the internal combustion engine, or
generating a whole motive torque power for vehicle running without
activating the internal combustion engine, for example.
FIG. 1 is a sectional side view showing an induction-type rotating
electric apparatus in a preferred embodiment of the present
invention, FIG. 2 is a sectional view showing a stator of the
induction-type rotating electric apparatus, and FIG. 3 is a
perspective view showing a cross section of a rotor of the
induction-type rotating electric apparatus. The induction-type
rotating electric apparatus is provided with a housing 1 having an
opening on one axial end side and a bottom on the other axial end
side, and a cover 2 for sealing the opening of the housing 1. The
housing 1 and the cover 2 are jointed by a plurality of bolts 3,
e.g., six bolts 3. On the inside of the housing 1, there is
provided a water channel formation member 22, and a stator 4 is
secured to the inside of the water channel formation member 22 by
means of shrinkage-fitting or the like. A flange shown on the
left-hand side of the water channel formation member 22 is secured
between the housing 1 and the cover 2, and a water channel is
formed between the water channel formation member 22 and the
housing 1. Cooling water for cooling the rotating electric
apparatus is fed into the water channel 24 through an inlet 32, and
after cooling the rotating electric apparatus, the cooling water is
fed out of an outlet 34.
The stator 4 comprises a stator iron core 412 having a plurality of
slots 411 formed circumferentially at equally spaced intervals, and
a three-phase stator coil 413 having a winding-around form thereof
in each of the plurality of slots 411. In the induction-type
rotating electric apparatus according to the present preferred
embodiment, a star connection (Y connection) is formed on the
stator coil 413 having an eight-pole structure, and for each phase,
there is provided an arrangement of 2Y connection in which a
formation of parallel connection is made on a pair of winding
parts. On the stator iron core 412 in which the stator coil 413 is
contained in a winding-around form, the plurality of slots 411,
e.g., a total of 48 slots 411 are provided. In the fabrication of
the stator iron core 412, a magnetic steel sheet having a thickness
of 0.05 to 0.35 mm, for example, is formed by punching or etching,
and then a plurality of magnetic steel sheets thus formed are
laminated on one another to provide a laminated structure in which
the plurality of slots 411 are disposed circumferentially at
equally spaced intervals in a radial formation.
On the inner circumferential side of the stator iron core 412, a
rotor 5 is rotatably disposed in a fashion that the rotor 5 faces
the stator iron core 412 via a minuscule air gap. The rotor 5 is
secured to a shaft 6 so that the rotor 5 rotates integrally with
the shaft 6. The shaft 6 is rotatably supported by a pair of ball
bearings 7a and 7b that are mounted on the cover 2 and housing 1
respectively. On the cover 2, the ball bearing 7a is secured to the
cover 2 with a retaining plate (not shown), and on the bottom side
of the housing 1, the ball bearing 7b is secured to a recessed part
formed on the bottom of the housing 1.
On the left-hand side of the shaft 6, a pulley 12 is mounted with a
nut 11. Between the pulley 12 mounted on the shaft 6 and the
bearing 7a, there are provided a sleeve 9 and a spacer 10. The
outer circumference of the sleeve 9 and the inner circumference of
the pulley 12 are formed in a substantially conical shape, and the
pulley 12 and the shaft 6 are rigidly integrated with a clamping
force of the nut 11 so that the pulley 12 and the shaft 6 can be
integrally rotated. When the rotor 5 is driven for rotation thereof
with respect to the stator 4, a turning force of the shaft 6 is
output externally via the pulley 12. In cases where the rotating
electric apparatus serves as a generator, a turning force is input
to the shaft 6 via the pulley 12.
As shown in FIG. 3, the rotor 5 of a squirrel cage type has a rotor
iron core 513, in which a plurality of conductor bars 511 extending
in the axial direction of rotation are embedded circumferentially
at equally spaced intervals on the outer circumferential side
thereof. The rotor iron core 513 is made of magnetic material, and
a short-circuit ring 512 for short-circuiting each conductor bar
511 is provided on both the axial ends of the rotor iron core 513.
To clarify the relationship between the rotor iron core 513 and the
conductor bar 511 in the perspective view of FIG. 3, a sectional
structure taken along a plane perpendicular to the axis of rotation
is shown without illustration of the short-circuit ring 512 and the
shaft 6 on the pulley 12 side.
In the fabrication of the rotor iron core 513, a magnetic steel
sheet having a thickness of 0.05 to 0.35 mm, for example, is formed
by punching or etching, and then a plurality of magnetic steel
sheets thus formed are laminated on one another to provide a
laminate structure. As shown in FIG. 3, on the inner
circumferential side of the rotor iron core 513, a plurality of
cavities each having a substantially fan shape are formed
circumferentially at equally spaced intervals for the purpose of
reduction in weight. On the outer circumferential side of the rotor
iron core 513, i.e., on the stator-facing side of the rotor iron
core 513, the plurality of conductor bars 511 are embedded, and a
magnetic circuit is produced on a rotor yoke 530 located on the
inner side with respect to each conductor bar 511. Bach conductor
bar 511 and each short-circuit ring 512, which are made of
aluminum, are integrated with the rotor iron core 513 by
die-casting. The short-circuit ring 512 located at each of both
ends of the rotor iron core 513 is so arranged that the
short-circuit ring 512 protrudes endwise in the axial direction
with respect to the rotor iron core 513. Although not shown in FIG.
1, a detection rotor for detecting rotations of the rotor 5 is
provided on the bottom of the housing 1. A rotation sensor 13
detects the number of teeth per unit time of the detection rotor
being rotated, and outputs electrical signals for detecting a
positioning of the rotor 5 and a rotating speed of the rotor 5.
Referring to FIG. 4, there is shown a connection diagram of the
stator coil 413 formed in 2Y connection. DC terminals of a
secondary battery 612 for driving and an inverter device 620 are
electrically connected with each other. The secondary battery 612
supplies the inverter device 620 with DC power, and then the
inverter device 620 feeds AC power to the three-phase stator coil
413 having a winding-around form thereof in each of the plurality
of slots 411 of the stator iron core 412. Thus, the stator coil 413
produces a rotating magnetic field in accordance with a rotating
speed corresponding to AC power frequency.
According to the present preferred embodiment, the stator coil 413
is provided with two star connection lines Y1 and Y2. The Y1
connection line comprises a U-phase winding Y1U, V-phase winding
Y1V, and W-phase winding Y1W; and the Y2 connection line comprises
a U-phase winding Y2U, V-phase winding Y2V, and W-phase winding
Y2W. The Y1 connection line and the Y2 connection are connected in
parallel, with each neutral point thereof connected. The winding
Y1U comprises coils U11, U12, U13, and U14 that are connected in
series, and the winding Y2U comprises coils U21, U22, U23, and U24
that are connected in series. Likewise, the winding Y1V comprises
coils V11, V12, V13, and V14 that are connected in series, and the
winding Y2V comprises coils V21, V22, V23, and V14 that are
connected in series, the winding Y1W comprises coils W11, W12, W13,
and W14 that are connected in series, and the winding Y2W comprises
coils W21, W22, W23, and W24 that are connected in series.
In the present preferred embodiment, a lap winding type of
distributed winding arrangement is adopted for the purpose of
reduction in coil end size, and each of the coils U11 to W24
comprises a pair of continuous coils 4131a and 4131b as shown in
FIG. 5(a). The coils 4131a and 4131b, each having the same number
of wire turns (e.g., three wire turns), are arranged to be
continuous via an interconnecting conductor 4134. Although an alpha
winding pattern is used for the coils 4131a and 4131b, there may be
provided a normal winding pattern therefor. In the rotating
electric apparatus according to the present preferred embodiment, a
total of 24 pairs of coils 4131a and 4131b are used, and each of
the coils 4131a and 4131b is fitted into a corresponding slot 411
thereof in the stator iron core 412.
In FIG. 4, the two coils 4131a and 4131b constituting the coil U11
are indicated by reference numerals 2 and 1, respectively. In FIG.
2, a winding-around form of the two coils 4131a and 4131b
constituting the coil U11, and a winding-around form of the two
coils 4131a and 4131b constituting the coil U12 are schematically
indicated by the broken line (4131a) and the solid line (4131b).
For each pair of coils 4131a and 4131b, a winding-around form is
provided between a pair of slots 411 in a fashion that four slots
are interleaved therebetween.
For example, in the case of the coil 4131b included in the coil
U11, a winding-around form is provided between No. 1 slot 411 and
No. 6 slot 411. In No. 1 slot, the rotor-side slot position
(top-side slot position) is used, and in No. 6 slot, the
bottom-side slot position is used. On the other hand, for the coil
4231a included in the coil U11, a winding-around form is provided
between the top-side slot position of No. 2 slot and the
bottom-side slot position of No. 7 slot. In the same manner, for
the coil 4131a included in the coil U12, a winding-around form is
provided between No. 38 slot 411 and No. 43 slot 411. For the coil
4131b included in the coil U12, a winding-around form is provided
between No. 37 slot 411 and No. 42 slot 411. It is to be noted that
the number of slots interleaved between a pair of slots for
winding-around coil formation such as in the manner mentioned above
depends on the total number of slots and the number of phases,
i.e., the number of interleaved slots is not necessarily four.
In FIG. 4 where the coil 4131a included in the coil 11 is indicated
by reference numeral 2 and the coil 4131b included therein is
indicated by reference numeral 1, the reference numerals 1 and 2
correspond to slot numbers assigned to the top-side slot positions
of the slots 411 in which the coils 4131a and 4131b are disposed.
In a total of 48 slots 411, "No. 1" is assigned to an arbitrary
slot 411, and subsequent serial numbers are assigned to the
remaining slots in the order of circumferential direction. The coil
4131a has a winding-around form between No. 2 slot 411 and No. 7
slot 411; in No. 2 slot 411, the rotor-side slot position (top-side
slot position) is used for insertion, and in No. 7 slot 411, the
bottom-side slot position is used for insertion.
As mentioned above, the numbers assigned to a pair of coils in FIG.
4 represent slot numbers corresponding to insertion of each coil on
the rotor side. Since the coils 4131a and 4131b in a pair are
inserted in adjacent slots 411, it is possible to reduce torque
pulsation.
Referring to FIG. 6, there is shown a positional relationship of
slots 411 and coil parts constituting the stator coil 413. In field
442 shown in FIG. 6, the slot numbers 1 to 48 assigned as mentioned
above are indicated. For example, the two coils 4131a and 4131b
constituting the coil U11 (i.e., No. 2 and No. 1 coils shown in
FIG. 4) are inserted to the rotor-side slot positions of No. 2 and
No. 1 slots. To clarify this arrangement, reference code U11 is
indicated below slot numbers 2 and 1 in the field 442. For example,
in the field 442, the coil W13 is indicated by slot numbers 29 and
30. That is to say, there is shown a structural arrangement in
which the coil W13 is formed with a series connection of the coil
4131a disposed at the rotor-side slot position of No. 29 slot 411
and the coil 4131b disposed at the rotor-side slot position of No.
30 slot 411.
In field 444 shown in FIG. 6, there are indicated stator winding
phases and allocations thereof. As mentioned above, the coils 4131a
and 4131b constituting the coil U11 are inserted to the rotor-side
slot positions of No. 2 and No. 1 slots 411. In the field 444, the
coils 4131a and 4131b constituting the coil U11 are both indicated
as [U1]. This means that a first position of U phase, i.e., a
reference position of U phase of the stator winding is used
therefor. The coils 4131a and 4131b constituting the coil U21 are
inserted to the rotor-side slot positions of No. 44 and No. 43
slots 411 as shown in the field 442, and the coils 4131a and 4131b
constituting the coil U21 are both indicated as [U2] in the field
444. This means that the coil U21 is located at a second position
of U phase of the stator winding, i.e., the coil U21 is located at
a mechanical angle position of 45.degree. with respect to the
reference position of U phase. In the same manner, the coils 4131a
and 4131b constituting the coil U12 are inserted to the rotor-side
slot positions of No. 38 and No. 37 slots 411 as shown in the field
442, and the coils 4131a and 4131b constituting the coil U12 are
both indicated as [U3] in the field 444. This means that the coil
U12 is located at a third position of U phase of the stator
winding, i.e., the coil U12 is located at a mechanical angle
position of 90.degree. with respect to the reference position of U
phase.
More specifically, in the winding Y1U shown in FIG. 4, the coil U11
is located at the reference position of U phase, and the coils U12,
U13, and U14 are located at a third position (a mechanical angle
position of 90.degree.), a fifth position (a mechanical angle
position of 180.degree.), and a seventh position (a mechanical
angle position of 270.degree.), respectively, with respect to the
reference position of U phase. On the other hand, the coils U21,
U22, U23, and U24 of the winding Y2U are located at a second
position (a mechanical angle position of 45.degree.), a fourth
position (a mechanical angle position of 135.degree.), a sixth
position (a mechanical angle position of 225.degree.), and an
eighth position (a mechanical angle position of 315.degree.),
respectively, with respect to the reference position of U phase as
shown in the field.
The coil V11 of the winding Y1V is shifted by two slot positions
with respect to the coil U11, i.e., the coil V11 is shifted through
a mechanical angle of 15.degree. with respect to the coil U11. The
position of the coil V11 is used as a reference position of V
phase, which is indicated as [V1] in the field 444. The coils V12,
V13, and V14 of the winding Y1V, which are connected in series with
the coil V11 of the winding Y1V, are indicated as [V3], [V5], and
[V7], respectively, in the field 444, i.e., the coils V12, V13, and
V14 of the winding Y1V are located at a third position (a
mechanical angle position of 90.degree.), a fifth position (a
mechanical angle position of 180.degree.), and a seventh position
(a mechanical angle position of 270.degree.), respectively, with
respect to the reference position of V phase. On the other hand,
the coil V21 of the winding Y2V, which is indicated as [V2] in the
field 444, is located at a position shifted through a mechanical
angle of 45.degree. with respect to the coil V11. The coils V22,
V23, and V24 of the winding Y2V, which are indicated as [V4], [V6],
and [V8] in the field 444, are located at a fourth position (a
mechanical angle position of 135.degree.), a sixth position (a
mechanical angle position of 225.degree.), and an eighth position
(a mechanical angle position of 315.degree.), respectively, with
respect to the reference position of V phase. Since the coil V11 of
V phase is shifted through a mechanical angle of 15.degree. with
respect to the coil U11 as mentioned above, each coil of V phase is
shifted through a mechanical angle of 15.degree. with respect to
each corresponding coil of U phase. Similarly, since the coil W11
of W phase is shifted through a mechanical angle of 30.degree. with
respect to the coil U11, each coil of W phase is shifted through a
mechanical angle of 30.degree. with respect to each corresponding
coil of U phase.
The following describes field 446 shown in FIG. 6. According to the
present preferred embodiment, respective coils 4131a and 4131b in
pairs are disposed in a winding-around form through respective
slots in pairs. More specifically, as mentioned above, the coil
4131a of the coil U11 has a winding-around form between No. 2 slot
411 and No. 7 slot 411 in a fashion that winding in No. 2 slot 411
is disposed at the rotor-side slot position thereof, and winding in
No. 7 slot is disposed at the bottom-side slot position thereof. In
the field 446, bottom-side slot position numbers are indicated. For
example, the coil 4131b of the coil U11 is disposed in a
winding-around form between No. 1 slot 411 and No. 6 slot 411 in a
fashion that winding in No. 1 slot 411 is disposed at the
rotor-side slot position thereof, and winding in No. 6 slot 411 is
disposed at the bottom-side slot position thereof.
In field 448 shown in FIG. 6, there are indicated phases of coils
disposed at bottom-side slot positions of slots 411 represented by
numbers in the field 442, and coil allocations of respective
phases. In field 450 shown in FIG. 6, there are indicated slot
numbers corresponding to allocations of coils in a winding-around
form indicated in the field 448. For example, as shown in the field
442, the coil 4131a of the coil U11 is inserted at the rotor-side
slot position of No. 2 slot 411. On the other hand, at the
bottom-side slot position of No. 2 slot 411, the coil 4131b of the
coil V21 is inserted which corresponds to insertion thereof at the
rotor-side slot position of No. 45 slot 411. Accordingly, "No. 45"
is indicated in the field 450. In the field 448, [V2] is indicated
which represents that the coil 4131b of the coil V21 is a second
coil of phase V.
Referring to FIG. 7, there is shown a perspective view of the
stator iron core 412 having a total of 24 coils (coils U11 to W24)
mounted in slots thereof in a state before the coils are connected
mutually. Each of the coils U11 to W24 comprises two coils 4131a
and 4131b that are connected via the inter-connecting conductor
4134 in an alpha winding pattern of a tandem connection type as
shown in FIG. 5(a). In lap winding, respective conductor terminals
211 and 212 of the coils U11 to W24 are concentrated on one axial
side of the stator iron core 412, i.e., a total of 48 conductor
terminals 211 and 212 are led out from a coil end 220 in the upward
direction as shown in FIG. 7. The conductor terminals 211 and 212
of each of the coils U11 to W24 are connected to the conductor
terminals 211 and 212 of an adjacent coil to be connected in series
as shown in FIG. 4.
Each of the coils U11 to W24 comprises a pair of coils 4131a and
4131b, and the conductor terminal 211 of each coil 4131a is led out
from the bottom-side slot position of each slot 411, whereas the
conductor terminal 212 of each coil 4131b is led out from the
rotor-side slot position of each slot 411. In the case of the coil
U11 for example, as shown in FIG. 4, the coil 4131a is provided in
a winding-around form between a pair of slots 411 indicated as No.
2 slot (rotor-side slot position) and No. 7 slot (bottom-side slot
position), and the beginning of coil winding corresponding to a
leading-out point of the conductor terminal 211 is positioned on
the No. 7 slot side (refer to FIG. 5(a)). On the other hand, the
coil 4131b of the coil U11 is provided in a winding-around form
between a pair of slots 411 indicated as No. 1 slot (rotor-side
slot position) and No. 6 slot (bottom-side slot position), and the
end of coil winding corresponding to a leading-out point of the
conductor terminal 212 is positioned on the No. 1 slot side.
For connection between the coil U11 and coil U12, the conductor
terminal 212 of the coil 4131b constituting the coil U11 is
connected to the conductor terminal 211 of the coil 4131a
constituting the coil U12 as shown in FIG. 5(b). In this case, the
conductor terminal 212 led out at the rotor-side slot position
(top-side slot position) is to be connected to the conductor
terminal 211 led out at the bottom-side slot position across an
upper part of the coil end 220, while it is required to minimize
the height of the coil end 220 for reduction in size of the
rotating electric apparatus. The following describes connection
structures designed for height reduction of the coil end 220 as
regards connection between the conductor terminal 212 on the inner
circumferential side of the coil end 220 and the conductor terminal
211 on the outer circumferential side of the coil end 220.
A First Connection Structure:
Referring to FIGS. 8(a)-8(d), there is shown a first connection
structure of the conductor terminals 211 and 212 according to a
preferred embodiment of the present invention.
Between the coils U11 and U12 shown in FIG. 5(a), a mechanical
angle shift of 90.degree. is provided as can be seen from FIG. 2.
However, as shown in FIG. 5, for connection between the coils U11
and U12, the conductor terminal 212 of the coil 4131b of the coil
U11 is connected to the conductor terminal 211 of the coil 4131a of
the coil U12. As shown in FIG. 2, the conductor terminal 212 of the
coil 4131b of the coil U11 is disposed at the top-side slot
position of No. 1 slot 411, and the conductor terminal 211 of the
coil 4131a of the coil U12 is disposed at the bottom-side slot
position of No. 43 slot 411. Accordingly, there is provided a
mechanical angle shift of 45.degree. between the conductor terminal
211 of the coil U11 and the conductor terminal 211 of the coil U12
to be connected with each other.
As shown in FIG. 8(a), the conductor terminal 211 on the outer
circumferential side of the coil end 220 is curved spiral-wise
along the coil end 220 toward the conductor terminal 212 on the
inner circumferential side of the coil end 220 so that a joint part
211a of the conductor terminal 211 is radially opposed to the
conductor terminal 212. The expression "curved spiral-wise" used
herein represents a state of conductor wire formation in which the
conductor terminal 211 is laid spiral-wise inward to a slight
extent along the coil end 220. It is to be noted that, for this
spiral-wise curving formation, the conductor terminal 211 on the
outer circumferential side is arranged to have a terminal length
longer than that of the conductor terminal 212 on the inner
circumferential side. In FIGS. 8(a)-8(d), the coil end 220 is shown
in a cylindrical form for the sake of convenience in
illustration.
Then, as shown in FIG. 8(b), the conductor terminal 212 on the
inner circumferential side is curved radially along the coil end
220 so as to bring a joint part 212a of the conductor terminal 212
close to the joint part 211a of the conductor terminal 211. To
prevent possible damage to a surface of the coil end 220 due to
thermal effect at the time of joint connection, the joint parts
211a and 212a are disposed at a certain distance position from the
coil end 220. In the case of the conductor terminals 211 and 212
shaped as shown in FIG. 8(b), the conductor terminals 211 and 212
can be segmented into two kinds of parts; joint parts 211a and
212a, and curved parts 211b and 212b. Thereafter, the joint parts
211a and 212a are connected mutually by means of TIG welding or the
like. As a technique for this connection and the other connections
to be described below, fusing, fusing-brazing, or
resistance-brazing may be used instead of TIG welding.
After completion of connection between the conductor terminals 211
and 212, the joint parts 211a and 212a are bent radially toward the
outer circumferential side of the coil end 220 as shown in FIG.
8(c). In this manner, the conductor terminal 212 is curved radially
outwardly from the inner circumferential side of the coil end 220,
and further the joint parts 211a and 212a are bent radially toward
the outer circumferential side of the coil end 220. Thus, there is
provided a total coil end height consisting of the height of the
coil end 220 itself before joint connection and the width of one
conductor terminal 212, making it possible to realize reduction in
coil end height. In cases where a conductor having a rectangular
cross section (flat-type conductor) is used as a coil wire
material, the joint parts 211a and 212a are connected mutually so
that the long sides of the rectangular cross sections of the joint
parts 211a and 212a are made to face each other. In this manner,
the connection between the joint parts 211a and 212a can be
secured, and also an increase in coil end height at the time of
joint connection can be limited to a dimension of the short side of
the rectangular cross section of the conductor. Needless to say, as
shown in FIG. 8(d), the short sides of the rectangular cross
sections of the joint parts 211a and 212a may be arranged to face
each other circumferentially for connection thereof.
Since there is a vacant space on the core back side of the coil end
220, the joint parts 211a and 212a may be bent further toward the
core back side as indicated by the broken line in FIG. 8(c). By
bending the joint parts 211a and 212a in the arrow direction AL to
provide the form indicated by the broken line, it is possible to
reduce the outer circumferential dimension of the coil end
structure including the joint parts 211a and 212a. In particular,
where the core back diametric dimension of the stator iron core 412
is relatively small, the above arrangement is advantageous to
prevent the joint parts 211a and 212a from protruding sidewardly
from the outer circumferential face of the stator iron core
412.
Furthermore, in cases where there is a vacant space available for
bending the joint parts 211a and 212a on the inner circumferential
side of the coil end 220, the joint parts 211a and 212a may be bent
toward the inner circumferential side of the coil end 220. Further,
instead of the conductor terminal 211 on the outer circumferential
side, the conductor terminal 212 on the inner circumferential side
may be curved spiral-wise toward the conductor terminal 211, or
both the conductor terminals 211 and 212 may be curved spiral-wise
so as to bring the conductor terminals 211 and 212 close to each
other.
A Second Connection Structure:
Referring to FIGS. 9(a)-9(d), there are shown explanatory diagrams
of a second connection structure of the conductor terminals 211 and
212 according to another preferred embodiment of the present
invention. As in the first connection structure mentioned above,
the conductor terminal 211 on the outer circumferential side of the
coil end 220 is curved spiral-wise along the coil end 220 so that
the joint part 211a thereof is opposed to the conductor terminal
212 on the inner circumferential side of the coil end 220 as shown
in FIG. 9(a). Then, as shown in FIG. 9(b), the conductor terminal
212 on the inner circumferential side is curved radially along the
coil end 220 so as to bring the joint part 212a of the conductor
terminal 212 close to the joint part 211a of the conductor terminal
211. Thereafter, the joint parts 211a and 212a are connected
mutually by means of TIG welding or the like. The procedural steps
up to here are similar to those in the first connection structure
described above.
Then, as shown in FIG. 9(c), the joint parts 211a and 212a are bent
circumferentially onto the upper end face or outer circumference of
the coil end 220. In this connection structure, there is provided a
total coil end height consisting of the height of the coil end 220
itself before joint connection and the substantial width of one
conductor terminal 212, making it possible to realize reduction in
coil end height. While the joint parts 211a and 212a of the
conductor terminals of a flat type are connected mutually so that
the long sides of the rectangular cross sections of the joint parts
211a and 212a are made to face each other radially in the example
shown in FIG. 9(b), the joint parts 211a and 212a may be connected
mutually so that the short sides of the rectangular cross sections
of the joint parts 211a and 212a are made to face each other
circumferentially as shown in FIG. 9(d).
In the second connection structure, since the joint parts 211a and
212a are bent circumferentially, the joint parts 211a and 212d can
be contained in a vacant space at an upper position of the core
back outside the coil end 220 even if the joint parts 211a and 212a
are long to a certain extent. Therefore, by disposing the joint
parts 211a and 212a in FIG. 9(b) at a height position with
sufficient allowance from the coil end 220, it is possible to
reliably prevent possible damage to a surface of the coil end 220
due to thermal effect at the time of joint connection. As in the
case of the first connection structure, the conductor terminal 212
on the inner circumferential side may be curved spiral-wise instead
of the conductor terminal 211 on the outer circumferential
side.
A Third Connection Structure:
Referring to FIGS. 10(a)-10(c), there are shown explanatory
diagrams of a third connection structure of the conductor terminals
211 and 212 according to another preferred embodiment of the
present invention. While either one of the conductor terminals 211
and 212 is curved spiral-wise in the first and second connection
structures, both the conductor terminals 211 and 212 are curved
spiral-wise in the third connection structure.
First, as shown in FIG. 10(a), the conductor terminal 211 on the
outer circumferential side of the coil end 220 is curved
spiral-wise along the coil end 220 toward the conductor terminal
212, and the conductor terminal 211 is curved radially inwardly to
a small extent in the vicinity of the midpoint between a
leading-out position of the conductor terminal 211 and a
leading-out position of the conductor terminal 212. The conductor
terminal 211 is thus curved to provide a form different from that
shown in FIG. 8(a). Next, as shown in FIG. 10(b), the conductor
terminal 212 on the inner circumferential side of the coil end 220
is curved spiral-wise along the coil end 220 toward the conductor
terminal 211. Then, at a point between the leading-out position of
the conductor terminal 211 and the leading-out position of the
conductor terminal 212, e.g., in the vicinity of the midpoint
therebetween, the conductor terminal 212 is curved outwardly to a
slight extent so that the left-hand side face of the joint part
212a of the conductor terminal 212 abuts with the right-hand side
face of the joint part 211a of the conductor terminal 211.
Thereafter, the joint parts 211a and 212a are connected mutually by
means of TIG welding or the like. In this step, it is preferable
that the side faces of the joint parts 211a and 212a be made to
abut with each other at a certain distance position from the coil
end 220 to prevent possible damage to a surface of the coil end 220
due to thermal effect at the time of joint connection.
Then, as shown in FIG. 10(c), the joint parts 211a and 212a are
brought downwardly into close contact with the coil end 220. Thus,
there is provided a total coil end height consisting of the height
of the coil end 220 itself before joint connection and the width of
one conductor terminal 212, making it possible to realize reduction
in coil end height. In cases where a flat-type conductor having a
rectangular cross section is used as a coil wire material, the
joint parts 211a and 212a are connected mutually so that the short
sides of the rectangular cross sections of the joint parts 211a and
212a are made to face each other. In this manner, an increase in
coil end height at the time of connection of the joint parts 211a
and 212a can be limited to a dimension of the short side of the
rectangular cross section of the conductor.
A Fourth Connection Structure:
Referring to FIGS. 11(a)-11(b), there is shown explanatory diagrams
of a fourth connection structure of the conductor terminals 211 and
212 according to another preferred embodiment of the present
invention. While the conductor terminals 211 and 212 are laid
spiral-wise across the coil end 220 for connecting the joint parts
211a and 212a in the first to third connection structures mentioned
above, one of the conductor terminals 211 and 212 is arranged to
penetrate the coil end 220 to extend to an opposite side for
connection between the joint parts 211a and 212a in the fourth
connection structure.
As shown in FIG. 11(a), the conductor terminal 211 on the outer
circumferential side of the coil end 220 is curved spiral-wise
along the outer circumference of the coil end 220 toward the
conductor terminal 212. Next, the conductor terminal 211 is run
radially through a coil-to-coil clearance on the coil end 220,
e.g., the conductor terminal 211 is formed to provide penetration
thereof radially along a tooth of the stator iron core 412 so that
the conductor terminal 211 is led out to the inner circumferential
side of the coil end 220. Then, the joint part 211a of the
conductor terminal 211 thus led out to the inner circumferential
side of the coil end 220 is connected to the joint part 212a of the
conductor terminal 212. In this step, as shown in FIG. 11(a), the
joint parts 211a and 212a are disposed at a certain distance
position from the coil end 220 to prevent possible damage to a
surface of the coil end 220 due to thermal effect at the time of
joint connection.
Then, as shown in FIG. 11(b), the joint parts 211a and 212a are
bent radially along the coil end 220. In cases where a flat-type
conductor having a rectangular cross section is used as a coil wire
material, the joint parts 211a and 212a are connected mutually so
that the short sides of the rectangular cross sections of the joint
parts 211a and 212a, i.e., the lateral sides of the joint parts
211a and 212a are made to face each other as shown in FIG. 11(a).
Thus, there is provided a total coil end height consisting of the
height of the coil end 220 itself before joint connection and the
short-side width of one conductor terminal. Instead of forming the
conductor terminal 211 on the outer circumferential side to provide
penetration thereof to the inner circumferential side, the
conductor terminal 212 on the inner circumferential side may be
formed to provide penetration thereof to the outer circumferential
side. In this case, the joint parts 211a and 212a are bent toward
the inner circumferential side.
Further, the joint parts 211a and 212a may be bent along the outer
circumference of the coil end 220. Thus, a vacant space available
on the upper side of the coil back can be used advantageously. In
this case, either the short sides or the long sides of the
rectangular cross sections of the joint parts 211a and 212a may
also be made to face each other for connection thereof.
A Fifth Connection Structure:
Referring to FIGS. 12(a)-12(b), there are shown explanatory
diagrams of a fifth connection structure of the conductor terminals
211 and 212 according to another preferred embodiment of the
present invention. As shown in FIG. 12(a), the conductor terminal
211 on the outer circumferential side of the coil end 220 is curved
spiral-wise along the coil end 220 so that the conductor terminal
211 is extended onto the inner circumferential side of the coil end
220. Then, on the inner circumferential side, the conductor
terminal 211 is folded back through an angle of 180.degree., and
the joint part 211a thereof is connected to the joint part 212a of
the conductor terminal 212 on the inner circumferential side. In
cases where a flat-type conductor having a rectangular cross
section is used as a coil wire material, the joint parts 211a and
212a are disposed so that the short sides of the rectangular cross
sections of the joint parts 211a and 212a are made to face each
other. Thereafter, the joint parts 211a and 212a are connected
mutually by means of TIG welding or the like. As in the case of the
fourth connection structure, the joint parts 211a and 212a are
disposed at a certain distance position from the coil end 220 to
prevent possible damage to a surface of the coil end 220 due to
thermal effect at the time of joint connection.
Then, as shown in FIG. 12(b), the joint parts 211a and 212a are
bent radially outwardly along the coil end 220. In this fifth
connection structure, there is also provided a total coil end
height consisting of the height of the coil end 220 itself before
joint connection and the short-side width of one conductor
terminal, making it possible to realize reduction in coil end
height. Further, there may also be provided such a modified
arrangement that the conductor terminal 212 on the inner
circumferential side of the coil end 220 is laid spiral-wise to
extend onto the outer circumferential side of the coil end 220, the
joint parts 211a and 212a are connected on the outer
circumferential side, and then the joint parts 211a and 212a thus
connected are bent toward the inner circumferential side.
A Sixth Connection Structure:
Referring to FIGS. 13(a)-13(b), there are shown explanatory
diagrams of a sixth connection structure of the conductor terminals
211 and 212 according to another preferred embodiment of the
present invention. First, as shown in FIG. 13(a), the conductor
terminal 212 on the inner circumferential side of the coil end 220
is curved spiral-wise along the coil end 220 in the radially
outward direction toward the conductor terminal 211. Then, on the
outer circumferential side, the joint parts 211a and 212a are
connected so that the side faces thereof are made to abut with each
other. In this step, the joint parts 211a and 212a are disposed at
a certain distance position from the coil end 220 to prevent
possible damage to a surface of the coil end 220 due to thermal
effect at the time of joint connection.
Then, as shown in FIG. 13(b), the joint parts 211a and 212a are
bent toward the inner circumferential side so that the joint parts
211a and 212a are brought downwardly into close contact with the
coil end 220. In the sixth connection structure, since the joint
part 212a of the conductor terminal 212 is folded back to the
curved part of the conductor terminal 212, there is provided an
increase in coil end height corresponding to a dimension of double
the width of one conductor terminal. However, as compared with a
conventional connection structure in which the joint parts 211a and
212a have a straight form, a total coil end height can be made
lower in the sixth connection structure. Instead of the conductor
terminal 212 on the inner circumferential side, the conductor
terminal 211 on the outer circumferential side may be curved in the
radially inward direction toward the conductor terminal 212, and
then on the inner circumferential side, the joint parts 211a and
212a may be folded toward the outer circumferential side.
In the first to sixth connection structures described above, a
total coil end height can be reduced substantially since the
conductor terminals 211 and 212 are connected across the coil end
220, and then the joint parts thereof 211a and 212a are bent or
folded at a vacant space position on the inner or outer
circumferential side of the coil end 220 or along the coil end
220.
A Seventh Connection Structure:
In a situation where a flat-type conductor used as a coil wire
material is relatively thick, it is rather difficult to curve or
bend the conductor terminals 211 and 212 freely at a small radius
of curvature in particular. For example, where the connection
structure demonstrated in FIGS. 8(a)-8(d) are adopted, there occurs
a difficulty in curving the conductor terminal 211 along the coil
end 220 in a three-dimensional form to meet the conductor terminal
212. Further, when the conductor terminal 211 is bent so that the
wide side faces of the conductor terminals 211 and 212 are opposed
to each other, a large space is occupied by this bending formation,
resulting in a total coil end height being increased on the
contrary.
To eliminate the need for curving or bending the conductor terminal
211 complicatedly in a three-dimensional form, there is provided a
seventh connection structure in which the wide side face of the
conductor terminal 212 to be bent radially outwardly (the long side
of the rectangular cross section thereof) is connected to the
narrow side face of the conductor terminal 211 (the short side of
the rectangular cross section thereof). First, as shown in FIG.
14(a), the conductor terminal 211 on the outer circumferential side
of the coil end 220 is curved spiral-wise along the coil end 220 as
far as possible so that the joint part 211a of the conductor
terminal 211 is located at a position corresponding to the
conductor terminal 212 on the inner circumferential side of the
coil end 220. In this step, the joint part 211a of the conductor
terminal 211 is disposed at a height level almost even with the
upper end face of the coil end 220.
Then, the joint part 211a of the conductor terminal 211 that has
been curved along the outer circumference of the coil end 220 is
bent through a substantially right angle with respect to the outer
circumference of the coil end 220, i.e., the joint part 211a is
bent radially outwardly. In this step, the joint part 211a is so
bent that the side faces thereof are positioned almost
perpendicularly with respect to the outer circumference of the coil
end 220. Then, as shown in FIG. 14(b), the conductor terminal 212
on the inner circumferential side is bent radially outwardly along
the upper end face of the coil end 220 so that the joint part 212a
thereof abuts with the joint part 211a. Thus, the wide side face of
the joint part 212a is in contact with the narrow side face of the
joint part 211a to provide a T shape in the cross-sectional
configuration of the joint parts 212a and 211a. Thereafter, with
the T shape held using a jig or the like, the joint parts 211a and
212a are connected mutually by means of TIG welding or the
like.
As mentioned above, by providing such a modified structural
arrangement that the joint part 211a of the terminal conductor 211
on the outer circumferential side is bent radially outwardly along
the wide side face thereof, even a thick flat-type conductor can be
bent easily without causing a large space to be occupied by the
bending formation. It is therefore possible to contain the
connected joint parts in a vacant space available on the core back
so that the connected joint parts do not protrude from the stator
iron core 412. In this connection structure, there is provided a
total coil end height consisting of the height of the coil end 220
before joint connection and the substantial width of one conductor
terminal 212, enabling reduction in coil end height.
While the conductor terminal 211 on the outer circumferential side
is curved spiral-wise toward the conductor terminal 212 on the
inner circumferential side and then the conductor terminal 212 is
bent radially outwardly along the upper end face of the coil end
220 in the example demonstrated in FIGS. 14(a)-14(b), there may
also be provided a modified arrangement in which the conductor
terminal 212 on the inner circumferential side is curved
spiral-wise toward the conductor terminal 211 on the outer
circumferential side and then the conductor terminal 211 is bent
radially inwardly along the upper face of the coil end 220 for
joint connection.
Referring to FIG. 15, there is shown a modified form of the seventh
connection structure shown in FIGS. 14(a)-14(b). While the
conductor terminal 212 on the inner circumferential side of the
coil end 220 is bent radially outwardly along the upper end face of
the coil end 220 in the example demonstrated in FIGS. 14(a)-14(b),
the conductor terminal 212 is skewed with respect to the radially
outward direction toward the conductor terminal 211. By skewing the
conductor terminal 212 in the bending thereof, it is possible to
decrease the extent of protrusion of the conductor terminals in the
radially outward direction from the circumference of the coil end
220. Further, in cases where the extent of protrusion of the
conductor terminals is almost equal to that in the seventh
connection structure shown in FIGS. 14(a)-14(b), the length of the
joint parts can be made longer for ensuring reliable connection
thereof.
An Eighth Connection Structure:
Referring to FIGS. 16(a)-16(b), there is shown an explanatory
diagram of an eighth connection structure of the conductor
terminals 211 and 212 according to another preferred embodiment of
the present invention. In the eighth connection structure, a notch
211c is formed on the joint part 211a of the conductor terminal 211
to be curved spiral-wise along the coil end 220. For connection of
the joint parts 211a and 212a, the conductor terminal 211 on the
outer circumferential side of the coil end 220 is first curved
spiral-wise along the coil end 220 as shown in FIG. 16(a).
As mentioned above, the notch 211c is formed on the joint part 211a
of the conductor terminal 211 beforehand; more specifically, the
notch 211 is formed on the short side of the rectangular section of
the joint part 211a of the conductor terminal 211. It is to be
noted that the width and depth of the notch 211c are adjusted
according to the width and thickness of the conductor terminal 211
on the inner circumferential side of the coil end 220. The
conductor terminal 211 is curved spiral-wise so that the notch 211c
is opposed to the conductor terminal 212 as shown in FIG.
16(a).
Then, the conductor terminal 212 is bent radially outwardly along
the upper end face of the coil end 220, the joint part 212a is
engaged into the notch 211c of the joint part 211a, and then the
conductor terminals 211 and 212 are positioned properly.
Thereafter, the joint parts 212a and 211a are connected mutually by
means of TIG welding or the like.
In the eighth connection structure, there is also provided a total
coil end height consisting of the height of the coil end 220 itself
before joint connection and the substantial width of one conductor
terminal 212, making it possible to realize reduction in coil end
height. Further, since the notch 211c is provided, the conductor
terminals 211 and 212 can be positioned easily, thereby allowing
the elimination of the need for a positioning jig or device at the
time of joint connection. Still further, it is possible to decrease
the extent of protrusion of the conductor terminals in the radially
outward direction from the circumference of the coil end 220.
Referring to FIGS. 17(a)-17(b), there are shown exemplary
modifications of the eighth connection structure. FIG. 17(a) shows
a first exemplary modification in which the notch 211c is formed on
the lower side face of the joint part 211a. In this case, although
the positioning of the conductor terminals 211 and 212 can also be
made reliably to facilitate welding work, a dimension "h" indicated
in FIG. 17(a) causes an increase in height at a connected point of
the joint part 212a. In a second exemplary modification shown in
FIG. 17(b), a through hole 211d is formed in the joint part 211a
instead of the notch 211c, and the joint part 212a is inserted into
the through hole 211d.
Conversely to the arrangement shown in FIGS. 16(a)-16(b), there may
also be provided such a modified arrangement that a notch or a
through hole is formed on the conductor terminal 212, the conductor
terminal 212 is curved spiral-wise along the coil end 220, and then
the conductor terminal 211 on the outer circumferential side is
bent in the radially inward direction. Further, while the notch
211c and the through hole 211d each having a rectangular shape
corresponding to the rectangular cross section of the conductor as
shown in FIG. 16(a) are used respectively in the exemplary
arrangements mentioned above, each of the notch 211c and the
through hole 211d may be shaped in such a form as a trapezoid,
triangle, circular arc sector, and elliptic arc sector according to
the shape of the cross section of a conductor wire material to be
used.
According to the preferred embodiments that have been described so
far, it is also practicable to provide the following modifications
as regards the applicability of the present invention to rotating
electric apparatus:
(1) While the induction-type rotating electric apparatus having
eight poles is taken as an example in the preferred embodiments
described above, the present invention is also applicable to a
stator winding of a permanent-magnet type of rotating electric
apparatus or the like. (2) Further, the present invention is
applicable to a stator winding of a generator. (3) Still further,
the present invention is applicable to a round conductor wire
material, not limited to a conductor wire material having a
rectangular cross-sectional shape. (4) Furthermore, while the lap
winding type of distributed winding arrangement is taken as an
example of stator winding in the preferred embodiments described
above, the present invention is applicable to a winding arrangement
in which conductor terminals to be connected are disposed
separately on the inner circumferential side and outer
circumferential side of the coil end 220, such as a wave winding
arrangement, for example.
It is to be understood that the present invention is not limited by
any of the details of description concerning the preferred
embodiments in the foregoing unless otherwise any of the features
of the invention is impaired.
The invention may be embodied in other specific forms without
departing from the spirit or essential characteristics thereof. The
present embodiments are therefore to be considered in all respects
as illustrative and not restrictive, the scope of the invention
being indicated by the appended claims rather than by the foregoing
description, and all changes which come within the meaning and
range of equivalency of the claims are therefore intended to be
embraced therein.
* * * * *