Information
-
Patent Grant
-
6317962
-
Patent Number
6,317,962
-
Date Filed
Tuesday, March 26, 199628 years ago
-
Date Issued
Tuesday, November 20, 200122 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Sughrue, Mion, Zinn, Macpeak & Seas, PLLC
-
CPC
-
US Classifications
Field of Search
US
- 029 596
- 029 598
- 029 609
- 029 606
- 310 42
- 310 216
- 310 218
-
International Classifications
-
Abstract
In a method for producing a stator of an alternating current dynamo-electric machine, a laminated assembly with a roughly rectangular parallelopiped shape is produced, and a stator coil assembly is disposed in slots of the laminated assembly. Thereafter, a cylindrical stator core is produced by bending the laminated assembly. The stator coil assembly can thereby be easily disposed in the slots at a higher density, and damage to the conductors of the stator coil assembly can be prevented.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for producing a stator of an alternating current dynamo-electric machine, for example, an alternating current generator for automobiles, which is driven by an automobile engine, or the like.
2. Description of the Related Art
FIG. 4
is a cross-sectional view showing an example of an alternating current generator for automobiles to which the present invention can be applied. In this figure, a rotor
1
includes a rotating shaft
11
, a pair of claw pole field cores
12
mounted to the rotating shaft
11
, and a field coil
13
fixed within the pair of field cores
12
. The rotating shaft
11
is rotated by transmitting a driving force of an automobile engine through a belt (not shown).
A stator
2
surrounding the rotor
1
includes a stator core
21
and a stator coil assembly
22
fixed to the stator core
21
. The inner peripheral surface of the stator
2
is opposed to the outer peripheral surface of the rotor
1
through a gap. The stator
2
is held in place between a front bracket
3
and a rear bracket
4
. Furthermore, the rotor
1
is supported by the front bracket
3
and the rear bracket
4
through bearings
31
and
41
respectively.
A conventional method for producing the stator
2
will now be described in conjunction with FIG.
5
. First, a strip
20
having a plurality of slots is cut from a long, narrow steel plate as shown in FIG.
5
. At this time, two strips
20
can be cut from one steel plate. Next, one strip
20
is wound into a ring to produce the stator core
21
having a prescribed semi-diameter as shown in
FIG. 6. A
plurality of slots
21
a
are provided on the inner peripheral surface of the stator core
21
.
On the other hand, the stator coil assembly
22
is formed into a cylindrical shape as shown in FIG.
7
. The cylindrical stator coil assembly
22
is brought into the inside of the cylindrical stator core
21
along a guide (not shown) by an assembling apparatus (not shown) while bending its end portion, and thereafter inserted into the slots
21
a
of the stator core
21
to obtain the stator
2
as shown in FIG.
8
.
Further, methods disclosed, for example, in U.S. Pat. No. 416,033 and Japanese Patent Laid-Open No. 52-34301 are known as methods for producing the cylindrical stator core
21
.
In the conventional method for producing the stator
2
as described above, the stator coil assembly
22
is inserted into the slots
21
a
after being pre-formed into the cylindrical shape so as to correspond to slots
21
a
disposed cylindrically. This assembly operation is complicated and the stator coil assembly
22
is sometimes damaged. Therefore, a production efficiency is reduced. Further, the stator coil assembly
22
cannot be inserted into the slots
21
a
at a higher density, so output cannot be improved.
SUMMARY OF THE INVENTION
The present invention has been achieved with a view toward solving the problems described above, and further, it is an object of the present invention to provide a method for producing a stator of an alternating current dynamo-electric machine which is capable of easily disposing a stator coil assembly in slots of a stator core at a higher density and which also is preventing damage to conductors of the stator coil assembly.
To this end, according to an aspect of the present invention, there is provided a method for producing a stator of an alternating current dynamo-electric machine, comprising the steps of: laminating a plurality of magnetic strips together to produce a laminated core assembly with a rectangular parallelopiped shape having a plurality of slots; disposing a stator coil assembly in the slot; and bending the laminated core assembly together with the stator coil assembly to produce a cylindrical stator.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a perspective view showing an example of an alternating current generator for automobiles as produced by a method of this invention;
FIG. 2
is a perspective view showing the stator core of
FIG. 1
before being formed;
FIG. 3
is a perspective view showing a laminated assembly of
FIG. 2
after disposing a stator coil assembly;
FIG. 4
is a cross-sectional view showing an example of an alternating current generator for automobiles;
FIG. 5
is a plan view showing strips which compose a stator core;
FIG. 6
is a perspective view showing a cylindrical stator core;
FIG. 7
is a perspective view showing a cylindrical stator coil assembly; and
FIG. 8
is a perspective view showing the stator core of
FIG. 6
after fixing the stator coil assembly of
FIG. 7
thereto;
FIG. 9
shows an embodiment of a laminated assembly; and
FIG. 10
shows the laminated assembly of
FIG. 9
in a bent state.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiments according to the present invention will now be described with reference to the accompanying drawings.
FIG. 1
is a perspective view showing an example of an alternating current generator for automobiles as produced by a method of this invention. In this figure, a stator
5
includes a cylindrical stator core
51
having a plurality of slots
51
a,
and a stator coil assembly
52
disposed in the slots
51
a
. Further, the stator core
51
has a single welded portion
51
b
somewhere on its circumference. The construction of the whole alternating current generator is the same as FIG.
4
.
A method for producing the stator
51
will now be described. First, strips
20
shown in
FIG. 5
are cut into a prescribed length. The strips
20
may have, for example, a width of 30 mm and a thickness of 1 mm. Thereafter, a plurality of cut strips
20
are laminated together to produce a laminated assembly
50
with a roughly rectangular parallelopiped shape as shown in FIG.
2
.
On the other hand, the stator coil assembly
52
is preformed into a shape which is generally flat and which needs not be further formed within the slots
51
a
of
FIG. 2
, and thereafter inserted into the slots
51
a
as shown in FIG.
3
. In other words, the stator coil assembly
52
is preformed before it is inserted into the slots
51
a
so as to be ready for the insertion. Next, the laminated assembly
50
is bent into a cylindrical shape by a forming machine (not shown) to produce the stator core
51
. After the bending process, both ends of the laminated assembly
50
are welded together along the welding portion
51
b
of FIG.
1
.
In the method for producing the stator
5
as described above, when the stator coil assembly
52
is to be inserted into the slots
51
a,
the stator coil assembly
52
is required to be moved only in one direction relative to the straight stator core
51
, so that the stator coil assembly
52
is easily disposed in the slots
51
a
at a higher density. Further, since no excess bending force is applied to the stator coil assembly
52
, damage to the conductors of the stator coil assembly
52
is prevented. Additionally, since it is not necessary to pre-form the stator coil assembly
52
into the cylindrical shape, production of the stator coil assembly
52
is facilitated. Therefore, production efficiency of the stator is increased.
Moreover, as shown in
FIG. 9
, it is also possible that slits
60
be provided on the bottom portion of the slots
51
a
of the laminated assembly
50
, making the laminated assembly
50
easier to be bent. As shown in
FIG. 9
the size of each of the slits
60
is set so that the slits
60
are compressed to disappear when forming the stator core
51
cylindrically, thus the slits
60
have no negative influence upon the magnetic field.
While in the above embodiment, one stator core
51
is made from one laminated assembly
50
, it is also possible that a cylindrical stator core is made by assembling a plurality of stator cores bent into circular arc shapes respectively.
Further, a method for producing a stator of this invention is applicable to alternating current dynamo-electric machines other than alternating current generators for automobiles.
Claims
- 1. A method for producing a stator of an alternating current dynamo-electric machine, comprising the steps of:(a) laminating a plurality of magnetic strips together to produce a laminated core assembly with a rectangular parallelopiped shape having a plurality of slots; (b) disposing a stator coil assembly in said slots; and (c) bending said laminated core assembly together with said stator coil assembly to produce a cylindrical stator.
- 2. A method for producing a stator of an alternating current dynamo-electric machine according to claim 1, further comprising the step of:(d) preforming said generally flat shaped stator coil assembly to be ready for insertion into said slots of said laminated core assembly.
- 3. A method for producing a stator of an alternating current dynamo-electric machine according to claim 1, further comprising the step of:(d) welding both ends of said laminated core assembly together after the step (c) of bending said laminated core assembly.
- 4. A method for producing a stator of an alternating current dynamo-electric machine, comprising the steps of:(a) laminating a plurality of magnetic strips together to produce a laminated core assembly having a rectangular parallelopiped shape and having a plurality of slots; (b) disposing generally flat shaped electrical windings in said slots; and (c) bending said laminated core assembly to form at least an arc of a cylindrical stator, wherein said laminated core assembly is bent after said electrical windings are disposed in said slots.
- 5. A method for producing a stator of an alternating current dynamo-electric machine according to claim 4, wherein said electrical windings constitute a stator coil assembly.
- 6. A method for producing a stator of an alternating current dynamo-electric machine according to claim 4, wherein said step (c) comprises the step of:(c1) bending said laminated core assembly to form a first arc of said cylindrical stator, wherein said first arc constitutes only a first portion of said cylindrical stator.
- 7. A method for producing a stator of an alternating current dynamo-electric machine according to claim 6, further comprising the steps of:(d) laminating a plurality of second magnetic strips together to produce a second laminated core assembly having a rectangular parallelopiped shape and having a plurality of second slots; (e) disposing second electrical windings in said second slots; and (f) bending said second laminated core assembly to form a second arc of said cylindrical stator, wherein said second laminated core assembly is bent after said second electrical windings are disposed in said second slots and wherein said first arc and said second arc form at least a portion of said cylindrical stator.
- 8. A method for producing a stator of an alternating current dynamo-electric machine according to claim 1, further comprising the step of:(d) providing slits on a bottom portion of said slots of said laminated core assembly to facilitate bending of said laminated core assembly.
- 9. A method for producing a stator of an alternating current dynamo-electric machine according to claim 8, wherein said slits have sizes such that said slits disappear when said laminated core assembly is bent to produce said cylindrical stator.
- 10. A method for producing a stator of an alternating current dynamo-electric machine according to claim 4, further comprising the step of:(d) providing slits on a bottom portion of said slots of said laminated core assembly to facilitate bending of said laminated core assembly.
- 11. A method for producing a stator of an alternating current dynamo-electric machine according to claim 10, wherein said slits have sizes such that said slits disappear when said laminated core assembly is bent to form at least said arc of said cylindrical stator.
Priority Claims (1)
Number |
Date |
Country |
Kind |
7-260339 |
Oct 1995 |
JP |
|
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
5234301 |
Mar 1977 |
JP |