JPH0465728B2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a metal plate laminate used as a laminated core of electrical equipment, etc., and more specifically to a caulking punch for laminating and caulking thin metal plates. This invention relates to an improvement in the shape of a protrusion.

``Prior art'' Conventionally, methods such as riveting and welding have been used to bind metal plate laminates such as laminated iron cores, as well as methods such as
There is a method for joining plate materials disclosed in Japanese Patent No. 58-41131.

The method for joining these plates is to extrude each plate so that the outer diameter of the protrusion is somewhat smaller than the inner diameter of the recess, and punch a through hole coaxial with the protrusion. Overlap the protruding part of the plate material so that it fits into the recessed part of the other plate material to be joined,
By press-fitting a punch having a diameter larger than the hole diameter into the through hole, the protrusion is expanded in the outer radial direction, and the outer circumferential surface of the protrusion and the inner circumferential wall surface of the concave portion of the plate material to be welded are pressed together. , it is possible to simultaneously position the plates.

``Problems to be Solved by the Invention'' However, the effective contact surface of the joint structure using this plate joining method is the entire circular outer periphery of the protrusion made of one closed curve, and the problem is that the bonding force is not sufficient. It was hot.

In addition, in a roll-up type laminated core made by winding a long thin metal plate, the metal thin plate is plastically deformed and the adjacent metal thin plate is rolled up after the punched protrusion is formed. It was difficult to accurately position the ejecting protrusion, and although a positioning pin was inserted after winding to correct the positional deviation of the ejecting protrusion, the entire ejecting protrusion was press-fitted at once with some parts remaining in place. In the part of misalignment,
The edges of the protrusion and the recess contact and deform, and as shown in FIG. 17, a gap 72 is created between the protrusion and the recess, reducing the already small contact area and reducing the contact surface during press-fitting. The pressure is greatly reduced and the bonding force between adjacent thin metal plates is significantly reduced. There is also a problem in that there is a significant difference in bonding strength between the press-fit parts that are joined with a gap and the press-fit parts that are joined without a gap, and stable strength cannot be obtained.

In the conventional method described above, by press-fitting a punch with a diameter larger than the hole diameter into the coaxial through-hole, it is possible to accurately fit the protrusion and the recessed part and position the plates with each other during joining. When applied to the production of the above-mentioned winding type laminated core, a long punch that axially pierces the laminated core and a mechanism for aligning the punch and the through hole are required, resulting in relatively high manufacturing costs. There is a problem with that.

In view of the above-mentioned problems, the present invention provides a binding structure for metal plate laminates that exhibits greater bonding force than conventional binding structures, reduces the decrease in bonding force due to positional deviation between punched protrusions, and provides stable strength. The purpose is to provide products at low cost.

"Means for Solving the Problem" As a specific means to achieve the above purpose, an annular recess is formed on the upper surface and an annular recess on the lower surface by punching and molding an arbitrary planar shape surrounded by an outer closed curve and an inner closed curve. A metal plate characterized in that metal plates each having an annular projection having a width slightly larger than the width of the annular recess are laminated, and the adjacent metal plates are fitted to each other by press-fitting the annular projection into the annular recess. A laminate is provided.

"Operation" According to the above configuration, when the part surrounded by the outer closed curve and the inner closed curve is stamped and formed, the annular projection protrudes from the lower surface of the metal plate, and the width of the annular projection is slightly larger than the width of the annular recess. Therefore, if the annular projection is press-fitted into the annular recess of the adjacent metal plate, the outer peripheral surface of the annular projection formed along the outer closed curve, the outer inner peripheral surface of the annular recess, and the inner closed curve are formed along the inner closed curve. The inner circumferential surface of the annular projection and the inner inner circumferential surface of the annular recess are pressed against each other, and the outer circumferential surface and the inner circumferential surface together serve as effective contact surfaces to which adjacent metal plates are fitted.

"Embodiments" Examples of the present invention will be described in detail below with reference to the drawings. A first embodiment of the present invention is shown in FIGS. 1 to 7. A fixed iron core 20 of a rotating electric machine is constructed by laminating a large number of annular metal veneers 21, 21..., and each metal veneer 21 has six protrusions 22, 22...
is formed. As shown in enlarged views in FIGS. 1 and 2, this protruding portion 22 is formed by stamping an annular portion 25 surrounded by two large and small concentric circles 23 and 24 as an outer closed curve and an inner closed curve. There is an annular recess 26 on the top surface of the metal veneer 21.
is formed, and an annular projection 2 is formed on the lower surface of the metal veneer 21.
7 is formed. When the annular portion 25 is punched and formed using a punch and die having a predetermined shape, an annular projection 27 protrudes from the lower surface of the metal veneer 21 . At this time, the diameter D ₁ of the outer circumference of the annular projection 27 is slightly larger than the diameter D ₂ of the outer circumference of the annular recess 26 , and the diameter D ₃ of the inner circumference of the annular recess 26 is
The diameter of the inner circumferential circle D is slightly larger than ₄ .

When the metal veneers 21 having the annular punched protrusion portion 22 having the above structure are laminated and pressed, and the annular protrusion 27 is press-fitted into the annular recess 26 as shown in FIG.
As shown by the arrow, the outer circumferential surface of the annular protrusion 27 receives a force acting in the radial direction from the outer circumferential surface of the annular recess 26 in the adjacent metal veneer 21, and its diameter decreases, while the inner circumferential surface of the annular protrusion 27 decreases in diameter. receives a force acting in the radial direction from the inner peripheral surface of the annular recess 26 in the adjacent metal veneer 21, and its diameter expands. In this way, since pressure is applied to the annular projection 27 from both the inner and outer surfaces, a large contact surface pressure is generated between the annular projection 27 and the annular recess 26, and both the inner and outer surfaces of the annular projection 27 and the annular recess 26 serve as effective contact surfaces. Therefore, the effective contact area between the two becomes large. In addition, the positions of the annular protrusion portions 22 of the adjacent metal veneers 21 are slightly shifted, so that a gap is created between the outer circumference and inner circumference of the annular protrusion 27 and the outer circumference and inner circumference of the annular recess 26 during press-fitting. Even if the annular protrusion 27 occurs, pressure in opposite directions acts on both the inner and outer surfaces of the annular protrusion 27 as described above, and the annular recess 6 holds the annular protrusion 27 in place, so that the contact surface pressure between the annular protrusion 27 and the annular recess 26 decreases. few. In addition, the iron core 2 of the rotating electric machine shown in Figs. 6 and 7
8 is a long metal thin plate 2 instead of the metal veneer 21
This is a wound type laminated iron core made by winding 9.
In this type of laminated core 28, it is difficult to accurately position the punched protrusion portion 22 due to elongation and distortion of the thin metal plate 29 due to winding, and the punched protrusion of the conventional structure cannot maintain sufficient bonding force. However, by forming the annular punched-out projection portion 22 described above, strong binding becomes possible. In particular, in the case of the laminated iron cores 20 and 28 of the rotating electric machine mentioned in the embodiment, since the bonding force per one annular punched protrusion part 22 is large, the number of annular punched protrusion parts 22 can be small, and the laminated This can lead to a decline in the magnetic properties of the iron core.

In a second embodiment of the present invention shown in FIGS. 8 to 12, an iron core 60 of a rotating electrical machine is a wound-type laminated iron core made by winding a long thin metal plate 61. The laminated core 60 has a slot portion 62 punched out,
After the protrusion part 63 is stamped and formed, it is wound, and a positioning pin (not shown) is inserted into the slot part 62 to correct the positional deviation of the protrusion part 63 in the laminated thin metal plates 61. Formed by one press fit. This laminated core 60
There are 8 protrusions 63, 63 per round.
is installed. As shown in enlarged views in FIGS. 9 and 10, this protruding portion 63 is formed by stamping and molding an annular portion 66 surrounded by an outer closed curve 64 and an inner closed curve 65 consisting of two large and small concentric circles. , is formed by projecting an inner peripheral solid portion 67 surrounded by an inner closed curve 65 by approximately 0.05 mm in a direction opposite to the direction in which the annular portion 66 is punched out. As a result, a solid portion 67 protruding from the outer periphery of the outer closed curve 64 is formed on the upper surface of the thin metal plate 61, and an annular recess 68 is formed, and an annular protrusion 69 is formed on the lower surface of the thin metal plate 61. Annular projection 69
A circular concave portion 70 is formed on the upper surface side of the outer circumferential portion. The annular projection 69 and the protruding solid portion 67 are formed by punching out the annular portion 66 and the solid portion 67 simultaneously in opposite directions using a press machine with a punch and die having a predetermined shape. Alternatively, after punching out the solid portion 67 of the inner periphery of the inner closed curve 65 by a desired protrusion height, punch out the outer periphery of the outer closed curve 64 in the opposite direction with a punch provided with a relief in the solid portion 67. It is molded using the following molding procedure. At this time, by slightly changing the punch diameter and die diameter, the diameter D ₅ of the outer circumference of the annular protrusion 69 becomes slightly smaller than the diameter D ₆ of the outer circumference of the annular recess 68, similar to the dimensioning in the first embodiment. The diameter D ₇ of the inner circumference of the annular recess 68 is larger than that of the inner circumference D ₈ of the annular protrusion 69 .
Make it slightly larger than .

A thin metal plate 61 having an annular punched protrusion portion 63 from which a solid portion 67 of the above structure protrudes is wound, laminated, and pressurized to form an annular protrusion 63 as shown in FIG.
When attempting to press-fit the annular projection 69 into the annular recess 68, the positions of the protrusions 63 on adjacent thin metal plates 61 do not necessarily match exactly due to distortion caused by expansion and contraction during winding of the thin metal plate 61, so the annular protrusion 69
The inner peripheral edge 70 and the outer peripheral edge 71 of the protruding solid portion 67 contact and deform. but,
Since the contact between the annular projection 69 and the solid portion 67 generates a force in the direction of correcting the positional deviation between the annular projection 69 and the annular recess 68, the solid portion 67
The positional deviation is corrected as the object moves along the protruding height of the object. As shown in FIG. 12, the outer circumferential surface of the annular protrusion 69 and the outer circumferential surface of the annular recess 68 are fitted and press-fitted in an ideal state with no gap 72 without any deformation. The outer peripheral surface of the press-fitted annular projection 69 receives a force acting in the radial direction from the outer peripheral surface of the annular recess 68 in the adjacent thin metal plate 61, and its diameter is reduced, while the inner peripheral surface of the annular projection 69 is reduced in diameter. The diameter of the annular recess 68 in the thin metal plate 61 expands in response to a force acting in the radial direction from the inner circumferential surface of the annular recess 68 . Since pressure is applied to the annular protrusion 69 from both the inner and outer surfaces in this way, a large contact pressure is generated between the annular protrusion 69 and the annular recess 68.
Since both the inner and outer surfaces with 8 serve as effective contact surfaces, the effective contact area between the two is large and the bonding strength is also strong. Furthermore, the bond between the outer circumferential surface of the annular protrusion 69 and the outer circumferential surface of the annular recess 68 due to pressure is stronger than the bond between the inner circumferential surface of the annular protrusion 69 and the inner circumferential surface of the annular recess 68 due to pressure. The contribution rate for this is extremely large. Therefore, even if the position of the protruding portion 63 is slightly shifted, the protrusion of the solid portion 67 will only create a gap 72 between the inner circumferential surface of the annular protrusion 69 and the inner circumferential surface of the annular recess 68. This makes it possible to press-fit the annular protrusion 69 and the annular recess 68 without creating a gap 72 between the outer circumferential surface of the annular protrusion 69 and the annular recess 68. Compared to the first embodiment, it is even smaller and almost nonexistent. This has an excellent effect in that even if there is a slight deviation in the protruding portion 63, it is possible to perform a strong bond without substantially reducing the bonding force.

The structure of the punched protrusion according to the present invention is most preferably a ring-shaped part surrounded by two concentric circles, one large and one small, from the viewpoint of ease of manufacturing, re-polishing, and repair of a jig for forming the punching protrusion. However, it is not necessarily limited to this. Figures 13 and 14
In a third embodiment of the invention shown in the figures, a protruding portion 30
A rectangle 31 as an outer closed curve to form
A square-shaped portion 33 surrounded by a rectangle 32 as an inner closed curve is stamped and molded to form a square-shaped annular recess 35 on the upper surface of the metal plate 34 and a square-shaped projection 36 on the lower surface. Also, Figure 15 and Figure 1
In a fourth embodiment of the invention shown in FIG.
To form the outer closed curve and the inner closed curve, an annular part 43 surrounded by two large and small concentric circles 41 and 42 is stamped and formed, and an annular recess 45 is formed on the upper surface of the metal veneer 44 and an annular recess 45 on the lower surface. A circular portion 4 forming an annular projection 46 and further surrounded by a concentric circle 48 from a solid portion 47 surrounded by a circle 42
9 is punched out to form a second recess 50 on the upper surface of the metal plate 44.
A second protrusion 51 is formed on the lower surface. The structure of these third and fourth embodiments is similar to that of the first embodiment described above, with a square-shaped annular projection 36,
Annular projection 46 and projection 51 and square-shaped annular recess 3
5. By fitting the annular recess 45 and the recess 50, the metal plates 34, 44 can be firmly bound together.

"Other Embodiments" The present invention is not limited to the details of the above embodiments. For example, the planar shape surrounded by the outer closed curve and the inner closed curve may be arbitrary.
In the square shape shown in the embodiment, a solid portion of the inner periphery surrounded by the inner closed curve may be made to protrude.

"Effects of the Invention" According to the present invention, an annular recess is formed on the upper surface of the metal plate by punching and forming an arbitrary planar shape surrounded by an outer closed curve and an inner closed curve, and a width slightly larger than the annular recess is formed on the lower surface of the metal plate. Since the structure was such that an annular protrusion of the same width was formed and the annular protrusion was press-fitted into an annular recess of an adjacent metal plate to bind the metal plate stack, the space occupied by the stamped protrusion was the same as that of the reference. Nevertheless, the outer circumferential surface of the annular protrusion and the outer inner circumferential surface of the annular recess formed along the outer closed curve,
In addition, the inner circumferential surface of the annular protrusion formed along the inner closed curve and the inner inner circumferential surface of the annular recess come into pressure contact with each other, resulting in a wide effective contact area and an extremely large bonding force. Since pressure is applied to the annular protrusion from both the inside and outside, there is less loss of bonding strength due to misalignment of the embossing protrusion, resulting in a strong and stable bond even when applied to large products or rolled-up metal plate laminated products. can be achieved. Moreover, since no punch or a mechanism for positioning the punch and the through hole is required, there are excellent effects such as no increase in cost.

[Brief explanation of drawings]

FIG. 1 is an enlarged plan view of essential parts of the first embodiment of the present invention, FIG. 2 is a sectional view thereof, FIG. 3 is a plan view showing the first embodiment of the present invention, and FIG. 4 is a side view thereof. Figure 5 is an enlarged sectional view of main parts showing a state in which two metal plates with annular protrusions formed in the first embodiment are laminated, and Figure 6 is a rolled-up laminated iron core to which the first embodiment is applied. A plan view, FIG. 7 is a side view thereof, FIG. 8 is a schematic perspective view showing a rolled-up laminated core in a second embodiment of the present invention, and FIG. 9 is an enlarged plan view of main parts showing the second embodiment. 11 and 12 are enlarged cross-sectional views of main parts showing the process of press-fitting the annular protrusion with the protruding solid part of the second embodiment and the state after press-fitting, and FIG. FIG. 13 is an enlarged plan view of the main part showing the third embodiment of the present invention, FIG. 14 is a sectional view thereof, FIG. 15 is an enlarged plan view of the main part showing the fourth embodiment of the invention, and FIG. Similarly, FIG. 17, which is a cross-sectional view, is an enlarged view showing a state in which a gap is generated between the protrusion and the recess in the conventional example. 20, 28, 60...Laminated core, 21, 34,
44... Metal plate, 23, 31, 41, 64... Outer closed curve, 24, 32, 42, 65... Inner closed curve, 26, 35, 45, 68... Annular recess, 2
7, 36, 46, 69... annular projection, 22, 3
0, 40, 63...Protruding portion, 61...Thin metal plate, 67...Solid portion.

Claims (1)

[Scope of Claims] 1. Forming an annular recess on the upper surface and an annular protrusion with a width slightly larger than the width of the annular recess on the lower surface by punching and molding an arbitrary planar shape surrounded by an outer closed curve and an inner closed curve. 1. A metal plate laminate, characterized in that adjacent metal plates are fitted to each other by stacking metal plates and press-fitting the annular protrusion into the annular recess. 2. The metal plate laminate according to claim 1, wherein the solid portion surrounded by the inner closed curve projects higher than the outer peripheral portion of the outer closed curve.