JPH09234523A - Laminating die device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the deformation and the strain of a core piece and to obtain the optimum irradiating point of a laser beam by dividing a back pressure block of a laminating die device into plural pieces and push-holding a laminated core from the outer direction with the energizing force of an elastic body. SOLUTION: In the laminated die device, the back pressure block 16 is divided into plural pieces. In the divided back pressure block 16, a penetration 16a passed through laser beam is arranged. The core piece 9a is punched out with a punch 1 and passed through in the die 4 and hold-laminated in the back pressure block 16. The size secured with the back pressure block 16 and the elastic body 7 is set to smaller than the other size of the core 9a by about 5-20μm at the one side. Therefore, each elastic body 7 is pushed through each back pressure block 16. By this constitution, this laminated core can correspond to a minute size variation of the core piece 9a and can hold the lamination in the condition of no deformation and strain in the core 9a, and even if the laminated core is taken out from the die, the good laminated core without developing the welding crack and detachment is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated die apparatus for laminating workpieces such as a motor core and an EI core in a die and welding them using laser light.

[0002]

2. Description of the Related Art In recent years, in order to reduce the size and improve the performance of a motor, a laminated core constituting a stator is divided into units of pole teeth, insulated and wound, and then joined in a predetermined number of rings. The manufacturing method of forming a stator is used. The subdivided laminated core is required to have dimensional accuracy and fixing strength, and the laser welding is used instead of the pack die that joins the core pieces by fitting the recesses and protrusions that have been subjected to the half blanking process, and welded in the die. The laminated mold device is in the limelight (see, for example, Japanese Patent Laid-Open No. 347561/1992).

The structure of a conventional laminated mold device will be described. 4 (a) is a structural cross-sectional view of a conventional laminated mold apparatus, FIG. 4 (b) is an enlarged plan sectional view of a back pressure block portion of the conventional laminated mold apparatus, and FIG. It is a perspective view of the laminated core which did.

In FIGS. 4 (a), 4 (b) and 5,
Reference numeral 1 is a plate material made of a hoop material, 9a is a core piece punched out from the plate material 1 in a predetermined shape, 9 is a predetermined number of core pieces 9a stacked inside a stacking die apparatus, and a welded joint 10 is welded with a laser beam. It is a laminated core. The structure of the laminated mold device is
Upper die 3 having a punch 2 for punching the outer periphery of the core piece 9a
And a lower die 5 having a die 4 into which the core piece 9a is pulled out.
Further, a back pressure block 6 having a holding hole 6b having a shape matching the outer peripheral shape of the core piece 9a is provided in the lower portion of the die 4 so that the punched core piece 9a can be horizontally held in a closely contacted state. The back pressure block 6 has a through hole 6a through which laser light passes, and an irradiation unit 8 for irradiating the laser light is arranged at a position facing the through hole 6a. The irradiation unit 8 is optically connected to a laser oscillator (not shown) installed outside.

The operation of the laminated mold apparatus having the above structure will be described below. First, the core piece 9a
Is punched from the plate material 1 by the punch 2 and then punched into the die 4. This core piece 9a has a back pressure block 6 on its side edge.
Each time one sheet is pulled out in a state of being in close contact with the inner surface of the holding hole 6b, the sheet is moved downward by the thickness of one sheet. Then, the irradiation unit 8 irradiates a laser beam toward the overlapping portion of the core pieces 9a to perform welding. This welding operation is performed by a pulse operation synchronized with the ram movement of the press, that is, the punching operation. By repeating this operation, the required number of laminated cores can be obtained. The laminated cores can be separated by stopping the irradiation of the laser beam for one pulse and stopping the laser welding of the superposition of the cores.

[0006]

However, in the above-mentioned conventional structure, when the back pressure is applied to the core pieces by the holding holes of the back pressure block and the core pieces are held in close contact with each other and laser welding is performed, the back pressure is reduced. If it is large, the core piece will be deformed or distorted in the holding hole of the back pressure block, and that state will be held and welded, so the laminated core taken out from the mold will be subject to stress strain of the material and spring back. Cracks and peeling defects occur at welded joints. Further, when there is no or a small back pressure, there is a problem that the core pieces cannot be held or the adhesion between the core pieces is weak and the dimension of the core pieces in the stacking direction is not stable, and the pieces are not welded and joined. . In addition to the above, the dimensional variation of the core piece in the stacking direction also occurs due to a variation of ± 5% of the plate thickness (generally 0.35 to 0.5 mm) of the plate material used for the core piece.

For this reason, holding holes of different sizes are previously prepared for changes in the state of cutting edges such as punches and dies of the mold and changes in the material specifications of the plate material (for example, material grade H23 / H18 / H14). Make a back pressure block that you have,
The optimum back pressure block was selected for the size of the punched core piece, and each back pressure block was exchanged and supported.

Further, since the penetration size of the joint portion of laser welding is set to be smaller than the thickness of two plate materials, in the conventional structure, the laser beam is the optimum irradiation point due to the cumulative deviation in the stacking direction of the core pieces. It was easy to get out of the overlapping seam between them, so that the welded joints could not be made and the laminated core was likely to fall apart, and it was necessary to frequently adjust the height of the laser beam. This back pressure block replacement work and laser light height adjustment work cause a great deal of time and material loss, resulting in a reduction in productivity.

The present invention solves the above-mentioned problems of the prior art by replacing the back pressure block of the laser laminated mold by changing the state of the cutting edge or the plate material, and frequently adjusting the height of the laser beam. The objective is to reduce material loss, improve productivity of the production line, and provide stable quality products (laminated core).

[0010]

In order to solve this problem, the present invention has a structure in which the back pressure block is divided into a plurality of blocks, and the laminated core is pressed and held from the outer peripheral direction by the biasing force of each elastic body.

Further, the die is provided with a through hole through which laser light passes, and the laser is irradiated through the through hole.

As a result, it is possible to improve the productivity of the production line and obtain a laminated core of stable quality.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention comprises a core punching punch for punching a plate material in a predetermined shape, a die for receiving a core piece punched by the punch, and a lower portion of the die. Arranged, back pressure block for holding a plurality of punched core pieces in a laminated state, and a laser irradiation unit for laser welding the cut surface of the laminated core, the back pressure block is divided into a plurality of, Each back pressure block is a laminated mold device in which the laminated core is biased by an elastic body in a direction of pressing and holding the laminated core from the outer peripheral direction, and the core piece is attached with an elastic body by each divided back pressure block. Since it is pressed and held by the force, there is no distortion or deformation, and it is possible to eliminate the back pressure block replacement work that has been carried out each time the state of the cutting edge or the material of the plate material is changed.

According to a second aspect of the present invention, a core punching punch for punching a plate material into a predetermined shape, a die for receiving a core piece punched by the punch, and a die disposed below the die are punched. A back pressure block for holding a plurality of core pieces in a laminated state, and a laser irradiation unit for laser welding the cut surface of the laminated core were provided, and the die was provided with a through hole through which laser light from the laser irradiation unit passes. This is a multi-layer mold device. By changing the welding work position from inside the back pressure block to inside the die, the cumulative deviation in the stacking direction of the core pieces becomes smaller, and the height of the laser beam is frequently adjusted. There is no need, and a stable quality laminated core with few welding mistakes can be obtained.

According to a third aspect of the present invention, a punch for punching a core for punching a plate material into a predetermined shape, a die for receiving a core piece punched by the punch, and a die arranged below the die for punching. A back pressure block that holds a plurality of core pieces in a laminated state, and a laser irradiation unit that laser-welds the cut surface of the laminated core, the through-hole provided with a laser beam from the laser irradiation unit in the die, Further, the back pressure block is divided into a plurality of pieces, and each back pressure block is a laminated mold device in which the laminated core is biased by an elastic body in a direction of pressing and holding the laminated core from the outer peripheral direction. Does not distort or deform because each divided back pressure block is pressed and held by the urging force of the elastic body.By changing the welding work position from inside the back pressure block to inside the die, the stacking direction of core pieces is accumulated. side Decreases, frequently also eliminates the need for the height adjustment of the laser beam, less stable quality laminated core of the welding mistakes can be obtained.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIG. 1 (a) is a structural cross-sectional view of a laminated die apparatus according to a first embodiment of the present invention, and FIG. 1 (b) is a back pressure block according to the first embodiment of the present invention. It is an expanded plane sectional view of a part. 1 (a) and 1 (b), 1 is a plate material, 9a is a core piece, 2 is a punch, 3 is an upper die, 4 is a die,
5 is a lower mold, 8 is an irradiation unit, and FIG.
The difference from the conventional configuration of (b) is that the back pressure block 16 is divided into a plurality of pieces instead of the back pressure block having the holding holes 6b, and the elastic body 7 is used to separate each back pressure block 16 from the outer peripheral direction. The point is that the structure is such that it is pressed and held toward the piece 9a. Reference numeral 16a denotes a through hole through which the laser beam of the back pressure block 16 divided into a plurality of parts passes, and is disposed in the two back pressure blocks 16 corresponding to the welded joints on the inner and outer circumferences of the laminated core. Similarly, 7a is a through hole provided in the elastic body 7 through which laser light passes.

The operation of the laminated mold apparatus configured as described above will be described with reference to FIGS. 1 (a) and 1 (b). The core pieces 9a are punched out by the punch 1 and sequentially drawn into the die 4 and passed therethrough to be held and laminated on the back pressure block 16. The size secured by the back pressure block 16 and the elastic body 7 is set to be slightly smaller than the outer size of the core piece 9a by approximately 5 μm to 20 μm on one side. Therefore, each elastic body 7 is compressed via each back pressure block 16. The elastic body 7 is preferably made of a compressible material such as urethane rubber, and can cope with a subtle dimensional change of the core piece 9a and can hold the core piece 9a in a laminated state without deformation or distortion. Even if taken out, a good laminated core free from weld cracking or peeling can be obtained.

(Embodiment 2) FIG. 2 is a structural sectional view of a laminated die apparatus according to a second embodiment of the present invention. In FIG. 2, 1 is a plate material, 9a is a core piece, 2 is a punch, and 3 is a punch. Upper mold,
Reference numeral 14 is a die, 14a is a through hole, 5 is a lower mold, and 8 is an irradiation unit. 4A and 4B is different from the conventional configuration in that the through hole through which the laser light passes is changed from the back pressure block to the die 14, and the through hole 1 through which the laser light passes is provided.
4a are provided at two locations corresponding to the inner circumference and outer circumference of the core piece 9a.

The welding error is caused by the variation of ± 5% of the plate thickness of the plate material 1 accumulated up to the welding work position.
In the structure of the laminated die apparatus in which the through hole 14a through which the laser light passes is provided, the welding work position is set in the vicinity of the cutting edge surface of the die with a small cumulative deviation, so that the overlapping point of the cores, which is the optimum irradiation point, is secured. Laser welding is possible.

(Embodiment 3) FIG. 3 (a) is a structural sectional view of a laminated die apparatus according to a third embodiment of the present invention.
FIG. 7B is an enlarged plan sectional view of a back pressure block portion according to the third embodiment of the present invention. 3 (a) and 3 (b)
1B is different in that the through-hole 16a of the back pressure block 16 of FIG. 1B and the through-hole 7a of the elastic body 7 are eliminated and the back pressure block 26 and the elastic body 17 are used. Omit it. It goes without saying that even more excellent effects can be obtained by incorporating the advantages described above.

[0021]

As described above, according to the present invention, since the optimum irradiation point of the laser beam can be obtained without any deformation or distortion in the core piece, it is possible to obtain a laminated core of stable quality without welding cracks or peeling. You can Furthermore, the back pressure block replacement work and the laser beam height adjustment work, which have been carried out each time due to changes in the state of the cutting edge, changes in the plate material, etc., can be eliminated, and productivity can be improved.

[Brief description of drawings]

FIG. 1A is a structural cross-sectional view of a laminated mold device according to a first embodiment of the present invention. FIG. 1B is an enlarged plan cross-sectional view of a back pressure block portion according to a first embodiment of the present invention.

FIG. 2 is a structural cross-sectional view of a laminated mold device according to a second embodiment of the present invention.

FIG. 3A is a structural cross-sectional view of a laminated mold device according to a third embodiment of the present invention. FIG. 3B is an enlarged plan cross-sectional view of a back pressure block portion according to the third embodiment of the present invention.

FIG. 4A is a structural cross-sectional view of a conventional laminated mold device. FIG. 4B is an enlarged plan cross-sectional view of a conventional back pressure block unit.

FIG. 5 is a perspective view of a laminated core of a laminated mold device.

[Explanation of symbols]

 1 plate material 2 punch 3 upper die 4,14 die 5 lower die 6,16,26 back pressure block 6a, 7a, 14a, 16a through hole 6b holding hole 7,17 elastic body 8 irradiation unit 9 laminated core 9a core piece 10 welding Joint

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H02K 15/02 H02K 15/02 FE

Claims (3)

[Claims] 1. A core punching punch for punching a plate material into a predetermined shape, a die for receiving a core piece punched by the punch, and a plurality of punched core pieces arranged below the die. It is equipped with a back pressure block that holds the laminated core and a laser irradiation unit that laser-welds the cut surface of the laminated core.The back pressure block is divided into multiple parts, and each back pressure block presses and holds the laminated core from the outer peripheral direction. A laminated mold device that is urged by an elastic body in the direction of doing. 2. A core punch for punching a plate material into a predetermined shape, a die for receiving a core piece punched by the punch, and a plurality of punched core pieces arranged below the die. A laminated die apparatus comprising: a back pressure block which is held in a state; and a laser irradiation unit which laser-welds a cut surface of a laminated core, and the die is provided with a through hole through which laser light from the laser irradiation unit passes. 3. A core punching punch for punching a plate material into a predetermined shape, a die for receiving a core piece punched by the punch, and a plurality of punched core pieces arranged below the die. A back pressure block for holding in a state and a laser irradiation unit for laser welding the cut surface of the laminated core, a through hole through which laser light from the laser irradiation unit passes, and a plurality of the back pressure blocks. A laminated mold apparatus in which the back pressure block is divided into pieces and each of the back pressure blocks is biased by an elastic body in a direction of pressing and holding the laminated core from the outer peripheral direction.