JP3309243B2 - Method and apparatus for assembling stator core - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for assembling a stator core used in a rotating electric machine such as an electric motor, and an assembling apparatus used for implementing the method.

[0002]

2. Description of the Related Art Conventionally, as disclosed in JP-A-61-124241, an arc-shaped yoke portion, a pole portion extending radially inward from the yoke portion, and a tooth at a radially inner end of the pole portion. And a plurality of divided cores each having a projection and a concave groove formed at one end and the other end in the circumferential direction of the yoke portion. It is known to assemble a stator coil by fitting in a groove to connect in a circumferential direction. In this case, the concave groove is formed as a dovetail groove, and the protrusion formed in the dovetail shape is pressed into the concave groove from the axial direction of the stator core.

[0003]

In the above-mentioned prior art, there is a problem that the press-fitting work of the split cores from the axial direction must be performed one by one in order, and the assembly of the stator core is troublesome. In view of the above, an object of the present invention is to provide a method for efficiently assembling a stator core and an assembling apparatus used for implementing the method.

[0004]

Means for Solving the Problems In order to solve the above problems,
The present invention includes an arc-shaped yoke portion, a pole portion extending radially inward from the yoke portion, and a tooth portion at a radially inner end of the pole portion. A plurality of divided cores each having a projection and a concave groove formed thereon are connected circumferentially by fitting the protrusion of one adjacent divided core into the concave groove of the other divided core to form a stator coil. In the assembling method, the protrusions can be press-fitted into the concave grooves from the circumferential direction, and the plurality of divided cores can be
Again and again placed separately, which after placement in an annular, all Osamu
By moving the tools radially inward in synchronization with each other,
The number of divided cores is simultaneously pushed inward in the radial direction, and the protrusion of each divided core is pressed into the groove of the adjacent divided core from the circumferential direction.

Further, an apparatus of the present invention for carrying out the above method comprises a base, and a movable plate which is provided above the base and which can be moved up and down. The divided core can be held on the base. A plurality of jigs are arranged radially and movably in the radial direction,
On the movable plate, a cam that pushes the plurality of jigs inward in the radial direction in synchronization with each other in conjunction with the lowering of the movable plate is vertically provided,
It is characterized by the following. In this case, it is desirable to form in each jig a recessed portion into which the split core can be inserted and set from above, and to form an engaging groove which can position and engage the teeth of the split core in the circumferential direction.

When the movable platen is lowered with each split core set on each jig, a plurality of jigs are pushed inward by a cam in a radial direction in synchronization with each other and held by these jigs. The plurality of divided cores approach in the circumferential direction, and the protrusion of each divided core is pressed into the concave groove of each adjacent divided core from the circumferential direction. Thus, the stator core can be efficiently assembled in one operation, and productivity is greatly improved.

Further, if the teeth of the divided cores are positioned by forming the engaging grooves in the jig as described above, the circumferential clearance between the teeth of the divided cores can be accurately controlled, and the variation in the clearance can be reduced. The occurrence of cogging can be reliably prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 denotes a split core as a structural unit of a stator core, which is formed by stacking a large number of punched pieces punched from a strip-shaped steel plate. The split core 1 includes an arc-shaped yoke portion 2, a pole portion 3 extending radially inward from the center of the yoke portion 2, and a tooth portion 4 at a radially inner end of the pole portion 3. A stator coil 5 is wound around the pole portion 3 via a bobbin 5a. A radially inner surface of the yoke portion 2 is flat along the end face of the coil 5 and is orthogonal to the pole portion 3. Formed on the surface.

A protrusion 6 and a concave groove 7 are formed at one end and the other end in the circumferential direction of the yoke portion 2, respectively. The protrusion 6 of each divided coil 1 is formed with a concave groove of each divided coil 1 adjacent in the circumferential direction. 7 can be press-fitted from the circumferential direction.

As clearly shown in FIGS. 1B and 1C, an intermediate portion between the projection 6 and the concave groove 7 extends straight at a constant width in a direction normal to each end face of the yoke portion 2. Straight part 6
a, 7a are formed, and the tip 6b of the protrusion 6 and the inner bottom 7b of the concave groove 7 are formed in a semicircular shape having the same diameter as the width of the straight portions 6a, 7a. Also, the protrusion 6 and the concave groove 7
A straight portion 6 is provided at a portion of each yoke portion 2 near each end face.
The narrow portions 6c, 7c, which are narrower than the straight portions 6a, 7a, and the wide portions 6d, 7d which widen from the narrow portions 6c, 7c toward the respective end surfaces of the yoke portion 2 are formed adjacent to the straight portions 6a, 7a. Have been. Note that the hanging portions 6c and 7c are
a, 7a are continuous with the side edges of the circle a having the same diameter as the width of the straight portions 6a, 7a through an arc of the circle a, and have the diameter of the circle a and the length of the chord of the circle a passing through the constricted portions 6c, 7c. The width of the constricted portions 6c, 7c is slightly (for example, about 0.05 mm) smaller than the width of the straight portions 6a, 7a by the difference from the above.

The widened portion 6d of the projection 6 and the widened portion 7d of the concave groove 7
However, the width and length of the straight portion 6a of the protrusion 6 are slightly larger than the width and length of the straight portion 7a of the concave groove 7. For example, when the radius of the radially outer surface of the yoke portion 2 is 79.5 mm and the width T of each end surface of the yoke portion 2 is 9.5 mm, the length L1 and the width of the straight portion 6a of the projection 6 are respectively set.
The length L2 and the width of the straight portion 7a of the concave groove 7 are set to 0.98 mm and 5.98 mm, respectively.

Further, since the radially inner surface of the yoke portion 2 is formed as a flat surface as described above, the concave groove 7 which is recessed in the normal direction from the end surface of the yoke portion 2 is gradually formed. From the radially inner surface of the yoke 2 and closer to the radially outer surface of the yoke portion 2. As a result, the groove 7 is inserted into the straight portion 7a.
Is formed so as to match the normal c passing through the center of the end face of the yoke portion 2 in the width direction, the bending rigidity of the groove wall 2a on the outer diameter side of the concave groove 7 becomes smaller than the groove wall 2b on the inner diameter side. Than the flexural rigidity of Therefore, in the present embodiment, the concave groove 7 is formed so that the center line b is slightly offset to the inner diameter side with respect to the normal line c, and the bending rigidity of the outer diameter side groove wall 2a and the bending of the inner diameter side groove wall 2b are changed. The rigidity is made equal.
In the case of the yoke portion 2 having the dimensions described above, when the offset amount of the center line b to the inner diameter side with respect to the normal line c is set to about 0.75 mm, the bending rigidity of both groove walls 2a and 2b becomes equal. As a matter of course, the projection 6 is also formed such that the center line b of the straight portion 6a is offset to the inner diameter side with respect to the normal line c passing through the center in the width direction of the end surface of the yoke portion 2.

According to the above configuration, the projection 6 of the split core 1
Is pressed into the groove 7 of the divided core 1 adjacent in the circumferential direction from the normal direction, the groove walls 2a on the outer diameter side and the inner diameter side of the groove 7 are formed.
2b, the narrowed portion 7c of the groove 7 is widened so as to allow the straight portion 6a of the protrusion 6 to pass through, and the straight portion 6a of the protrusion 6 is narrowed by the narrowed portion 7c of the groove 7.
When passing through, the straight portion 7a of the groove 7 and the narrow portion 7
b presses against the straight portion 6a and the constricted portion 6b of the projection 6. Then, the split core 1 having the fitting portion between the protrusion 6 and the concave groove 7 as a fulcrum by pressing the straight portions 6a and 7a together.
Of the projection 6 and the straight portion 6a of the projection 6
Is slightly longer than the length of the straight portion 7a of the concave groove 7, the narrowed portion 6c of the projection 6 and the narrowed portion 7 of the concave groove 7 are formed.
c is secured in the normal direction, and as a result, circumferential play between the divided cores 1 and 1 adjacent in the circumferential direction is completely eliminated. In addition, since the outer wall and the inner wall 2a, 2b of the concave groove 7 have the same bending stiffness, the groove walls 2a, 2b are uniformly bent, and the protrusion 6 is formed on the concave groove 7 on the center line thereof. To fit correctly. Thus, in the state where the end faces of the yoke portions 2 and 2 perpendicular to the normal line are brought into close contact with each other, the divided cores 1 and 1 which are adjacent in the circumferential direction can be accurately formed without generating backlash or radial steps. Can be linked.

The stator core is assembled by connecting a plurality of the split coils 1 in a ring shape in the circumferential direction, and the assembly is performed by using an assembling apparatus shown in FIGS.
The assembling apparatus is configured by a device similar to a press device, including a base 10 and a movable platen 11 provided above the base 10 and moved up and down by a press drive source such as a ram.

A support plate 12 having a plurality of guide holes 12a formed radially is attached to the upper surface of the base 10.
A plurality of jigs 13 capable of holding the divided cores 1 are radially arranged on the support plate 12, and guide projections 13a provided on the lower surface of each jig 13 are engaged with each guide hole 12a.
On the base 10, the presser plate 14 ₁ of the central portion for preventing the Ri floating of the jig 13, the outer peripheral portion of the annular holding plate 14 ₂ and the respective struts 14a, attached via 14b, and the jig 13 It is slidably supported in the radial direction along each guide hole 12a.

Each jig 13 is provided with a recess 13b into which the split core 1 can be inserted and set from above, and a radially inward portion of the recess 13b has a rising end at the inner end as shown in FIG. A pair of small projections 13 with an interval
d, 13d, and the rising portion 13c and the small protrusion 1 are provided.
3d and 13d form an engaging groove 13e that can engage with the tooth portion 4 by positioning it in the circumferential direction.

On the lower surface of the movable platen 11, a cam 15 having an inclined cam surface 15a at the lower end capable of contacting the inclined surface 13f at the outer end in the radial direction of each jig 13 is vertically provided. An annular pad 16 which comes into contact with the yoke portion 2 of the divided core 1 from above to prevent the divided core 1 from floating is provided with a spring 1
It is attached by being urged downward at 6a. In this embodiment, the cams 15 are individually provided for each jig 13, but a single annular cam shared by all the jigs 13 may be provided.

When assembling the stator core, first, as shown in the left half of FIG. 2, the movable platen 11 is returned to the upper position, and all the jigs 13 are returned to the radially outward position. Then, each divided core 1 is set on each jig 13.
In this state, as shown in the left half of FIG. 3, the tip 6b of the protrusion 6 of each split core 1 enters the widened portion 7b of the concave groove 7 of the adjacent split core 1 in the circumferential direction. Thus, the plurality of split cores 1 are arranged in an annular shape.

Next, as shown in the right half of FIG. 2, the movable platen 11 is lowered. According to this, all the jigs 13 are pushed by the cams 15 and radiated synchronously with each other. The plurality of divided cores 1 held by these jigs 13 approach in the circumferential direction. And the projection 6 of each divided core 1
Are press-fitted in the circumferential direction, that is, the normal direction of the end face of the yoke portion 2 into the concave groove 7 of each divided core 1 adjacent in the circumferential direction, and as shown in the right half of FIG. The core 1 is connected in the circumferential direction.

In this state, the straight portion 6a of the projection 6
The straight portion 7a of the concave groove 7 and the narrowed portion 7
c are pressed against each other with a sufficient interference as described above, and the divided cores 1 are connected to each other without play, and the flatness between the divided cores 1 is also secured by preventing the floating of the divided cores 1 by the pads 16. Further, since the teeth 4 of each divided core 1 are positioned in the circumferential direction by the engagement grooves 13e of each jig 13, the clearance between the teeth 4, 4 of the adjacent divided cores 1, 1 is constant. An aligned and thus high quality stator core is obtained.

[Brief description of the drawings]

1A is a plan view of an example of a split core which is a constituent unit of a stator core assembled in the present invention, FIG. 1B is an enlarged plan view of a projection of the split core, and FIG. Figure

FIG. 2 is a longitudinal sectional view of an example of an assembling apparatus according to the present invention.

FIG. 3 is a plan view cut along the line III-III of FIG. 2;

FIG. 4 is a perspective view of a jig provided in the assembling apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Split core 2 Yoke part 3 Pole part 4 Teeth part 6 Projection 7 Concave groove 10 Base 11 Movable plate 13 Jig 13b Recessed part 13e Engagement groove 15 Cam

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H02K 15/02 B23P 19/04 H02K 1/14 H02K 1/18

Claims (3)

(57) [Claims] 1. A yoke portion having an arc shape, a pole portion extending radially inward from the yoke portion, and a tooth portion at a radially inner end of the pole portion. A plurality of divided cores each having a projection and a concave groove formed thereon are connected circumferentially by fitting the projection of one adjacent divided core into the concave groove of the other divided core. a method of assembling a, to allow press-fit from the circumferential projections in the concave groove, a plurality of divided cores, a plurality of jigs which can move in the radial direction
After installing them individually and arranging them in a ring, remove all the jigs
By moving inward in the radial direction in synchronization with each other, multiple
A method for assembling a stator core, comprising: simultaneously pushing radially inward of split cores, and press-fitting projections of each split core into concave grooves of adjacent split cores from a circumferential direction. 2. A yoke portion having an arc shape, a pole portion extending radially inward from the yoke portion, and a tooth portion at a radially inner end of the pole portion. A plurality of divided cores each having a projection and a concave groove formed thereon are connected circumferentially by fitting the projection of one adjacent divided core into the concave groove of the other divided core. An apparatus for assembling, comprising: a base; and a movable plate vertically movable provided above the base. A plurality of jigs capable of holding divided cores are radially and radially provided on the base. Wherein the movable plate is provided with cams which push the plurality of jigs radially inward in synchronization with each other in conjunction with the lowering of the movable plate. apparatus. 3. Each of the jigs is formed with a recessed portion into which a split core can be inserted and set from above, and an engaging groove which can be engaged by positioning the teeth of the split core in a circumferential direction. The stator core assembling apparatus according to claim 2, wherein: