JPH0555771U - Skew laminated iron core for rotor and die equipment for its production - Google Patents

Abstract

(57) [Summary] [Purpose] A skew laminated iron core for a rotor and a die assembly for manufacturing, in which a crimping protrusion is formed in a state where a necessary crimping area is secured and sufficient crimping strength is obtained. [Structure] Each iron core piece is provided with a caulking projection that is elongated in the radial direction and that forms a concave portion on the upper surface side and a convex portion on the lower surface side. The concave portion and the convex portion are displaced in the circumferential direction by a desired skew amount. The caulking protrusions are arranged so that they are vertically adjacent to each other, and the concave portions of the lower iron core piece and the convex portions of the upper iron core piece, which are vertically stacked, are caulked in a fitted state in which they are aligned in the circumferential direction. Iron core. In the forming process of the caulking projections described above, punches are provided in the die in a circumferential direction so as to be displaced by the skew amount per iron core piece. A progressive feed die apparatus for manufacturing skew laminated iron cores, which is provided with a rotation imparting device for rotating the blades to align the concave portions and the convex portions of the caulking protrusions of the iron core pieces laminated one above the other.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a skew laminated core used particularly for a rotor of a small electric motor, and a progressive die apparatus for manufacturing the same.

[0002]

[Prior Art]

 Skew laminated iron cores for rotors of electric motors are manufactured by sequentially feeding a predetermined number of iron core pieces when the core pieces press-formed from a strip-shaped thin plate material (strip material) by a progressive die device are sequentially removed in the outer shape punching process. It is fixed in a laminated state. For this purpose, each core piece is pre-formed with a caulking projection that forms a concave portion on the upper surface side and a convex portion on the lower surface side, and the concave and convex portions of the vertically adjacent iron core pieces are punched out and simultaneously caulked. In addition, the iron core pieces for each predetermined number are provided with a punching hole for separation into which the convex portion of the caulking projection is loosely fitted for weighing. Further, if the punched core pieces are sequentially laminated at the same positions, the plate thickness deviations of the core pieces are accumulated and the dynamic balance of the rotor is deteriorated, resulting in uneven rotation and reduced magnetic performance. For this reason, in the outer shape punching process, the outer shape punching dies are rotated by a certain angle to displace (skew) the vertically adjacent core pieces by a certain angle while punching the core pieces and stacking them in a skewed state.

As described above, examples of prior art relating to a laminated core for a rotor that is laminated in a skewed state include those disclosed in Japanese Patent Publication No. 55-11940 and Japanese Utility Model Publication No. 53-53183. As shown in FIGS. 4 and 5, in the laminated rotor core 20 for rotors, a staking caulking projection 23 having a cut and raised shape is provided adjacent to the escape hole 22 for skew which is preliminarily formed in the magnetic pole plate surface of the iron core piece 21. The core pieces 21 are formed so as to extend along the circumferential direction, and in the outer shape punching process, the inclined portions 23a of the caulking projections 23 of the respective core pieces 21 are stacked to provide skew. ..

[0004]

However, a large space is required in the circumferential direction in the skew lamination using the above-described caulking projection 23 of the related art, and in particular, the core piece 21 such as the laminated core for the rotor of the small electric motor is required. When the width of the magnetic pole plate surface is narrow, it is not possible to secure a sufficient space for forming the escape hole 22 for skewing and the crimping projection 23. Therefore, if the crimping projection 23 is made small, the crimping area becomes small. There was a drawback that the required caulking strength could not be obtained due to the decrease. Therefore, in the present invention, even if the width of the magnetic pole plate surface of the iron core piece is small as in the laminated core for the rotor of the small electric motor, the caulking projection can be formed in a state where the necessary crimping area is secured. It is an object of the present invention to provide a skew-stacked layer iron core for a rotor and a die device for manufacturing the same, which is capable of obtaining sufficient caulking strength.

[0005]

[Means for Solving the Problems]

 The first gist of the present invention is that each of the skew-stacked iron core pieces has a caulking projection that is elongated in the radial direction and that forms a concave portion on the upper surface side and a convex portion on the lower surface side. The concave portion and the convex portion are arranged so as to be displaced by a desired skew amount in the circumferential direction, and the concave portion of the caulking protrusion of the lower iron core piece and the convex portion of the caulking protrusion of the upper iron core piece that are stacked vertically adjacent to each other. And are skew laminated cores for rotors of small electric motors, which are crimped in a fitted state aligned in the circumferential direction.

A second gist of the present invention is that the press-formed core pieces are extended in the radial direction in a radial direction with respect to each core piece before the outer shape punching step of sequentially crimping the core pieces in a laminated state at the same time. A step for forming a caulking projection is provided in which a concave portion is formed on the upper surface side and a convex portion is formed on the lower surface side. In the forming step of the caulking projection, one iron core piece is circumferentially attached to the die. The punches are provided in a position shifted by an amount corresponding to the skew amount, and in the outer shape punching step, the die side is rotated in the circumferential direction by an amount corresponding to the skew amount for each iron core piece, and the lower iron core piece already stacked is stacked. It is a progressive die device for manufacturing a skew-stacked layer iron core for a rotor, which is provided with a rotation imparting device for aligning the concave portion of the crimping projection with the convex portion of the crimping projection of the upper core piece to be newly punched.

[0007]

【Example】

 Hereinafter, a skew laminated iron core for a rotor of a small electric motor and a mold device for manufacturing the same according to the present invention will be described in detail with reference to the illustrated embodiments. As shown in FIG. 1, this progressive feed die apparatus is composed of an upper die 1 and a lower die 2 which are vertically arranged, and punches a strotted hole along a feeding direction F of a strip thin plate material (strip material) W. A process A, a shaft hole punching process B, a caulking portion forming process C, an outer shape punching and a laminated caulking process D are respectively provided. A strip-shaped thin plate material (strip material) W is intermittently fed at a predetermined pitch in the feed direction F between the upper die 1 and the lower die 2, and the upper die 1 and the lower die 2 act as A to C between them. In each step, desired strip forming is performed on the strip thin plate material W, and in step D, the core pieces that have been sequentially punched out are caulked and fixed in a laminated state to manufacture a laminated iron core for a rotor. It

Although the above basic structure is the same as the conventional case, in the progressive die apparatus of the present invention, a new concept for solving the conventional problem is to form the caulking portion C and to punch the outer shape. And laminating and caulking step D. First, the caulking portion forming process C is divided into a measuring through-hole punching process C1 and a caulking protrusion forming process C2, and the upper die 1 is attached to the measuring through-hole punching process C1. The punch 3a and the die 4a formed on the lower die 2 are provided, and the punch 3b attached to the upper die 1 and the die 4b formed on the lower die 2 are provided in the step C2 of forming the caulking projection. There is. The punching process C1 for punching the measuring through hole and the forming process C2 for the caulking projection are operated such that when one of them is in the operating state, the other is in the non-operating state. The punch 3a and the punch 3b are switched by a control means (not shown). At the same time, the punch 3a cooperates with the die 4a to punch the measuring through hole 11a on the first (lowermost) core piece 11 of the laminated core 10 and the punch 3b As shown in FIGS. 2 and 3, the caulking projections 15 are formed on the second to the uppermost core pieces 12 to 1n of the laminated core 10 in cooperation with the die 4b. The caulking projection 15 is formed by a concave portion 15a concavely provided on the upper surface side of each of the iron core pieces 12 to 1n and a convex portion 15b convexly provided on the lower surface side, and the concave portion 15a and the convex portion 15b are formed. Is arranged in a state of being displaced by a desired skew amount d in the circumferential direction of each of the core pieces 12 to 1n, and extends slenderly along the radial direction with respect to the magnetic pole plate surface of each of the core pieces 12 to 1n. The rectangular shape or the oval shape of the embodiment is formed. For this reason, the punch 3b and the die 4b in the forming step C2 for forming the caulking projection 15 are arranged such that the relative positions thereof are circumferentially displaced by the skew amount d. In the punching step C1 as well, the punch 3a and the die 4a are similarly arranged with their relative positions displaced.

Next, in the outer shape punching and stacking caulking step D, the iron core pieces 11 to 1n in which the weighing through hole 11a and the caulking projection 15 are formed in the previous step C are attached to the upper die 1. A punch 5 is punched out of its outer shape to be separated from the strip-shaped thin plate material W, and a die 6 attached to the lower die 2 and a squeeze ring 7 whose inner diameter portion is continuous with the die 6 to hold the outer shape of each core piece. It is pulled in one by one. In order to displace the die 6 and the squeeze ring 7 on the lower mold 2 side of this process D before the punching of the outer shape by the punch 5 to displace the iron core piece that has already been extracted by the above-mentioned skew amount d. The rotation imparting device 8 is provided. As the rotation imparting device 8, for example, the rotation of the crankshaft of the press is converted into a constant rotation angle (skew angle) synchronized with the press stroke via a cam or the like, and the plate thickness deviation is eliminated via an index drive. For converting the rotation angle and the skew angle to a constant rotation angle, driving the servo motor or stepping motor in synchronization with the press stroke, and using the timing belt, timing gear, etc., the die 6 and squeeze ring 7 It is possible to use the conventionally known means for transmitting the

By providing the above-described rotation imparting device 8, the caulking of the second iron core piece 12 which is subsequently drawn into the measuring through hole 11a of the first iron core piece 11 which is first drawn The convex portion 15b of the second projection 15 is crimped in an aligned state, and the convex portion 15b of the third crimp projection 15 of the third iron core piece 13 that is pulled out is the convex projection 15b of the second iron piece 12. It is caulked in the concave portion 15a of 15 in an aligned state. For the new core pieces that are sequentially drawn in the same manner below, the concave part of the caulking projection of the lower iron core piece and the convex part of the caulking projection of the upper iron core piece that are stacked vertically adjacent to each other are in the circumferential direction. When the predetermined number n is punched out, the iron core pieces 11 for separation having the measuring through holes 11a punched out are laminated. As a result, the laminated core 10 is integrally caulked in a state where the required number of laminated layers required for one product is regulated, and the vertically adjacent core pieces are separated by a desired skew amount in the circumferential direction. They are staggered and stacked. Since the caulking projection 15 has a shape in which the convex portion 15a and the concave portion 15b are offset from each other, the depth of the concave portion 15a is preferably within 2/3 of the thickness of the iron core piece from the viewpoint of strength, for example, about 1/2. Is enough.

[0011]

[Effect of the device]

 As described above, in the skew laminated iron core for a rotor of the present invention, the concave and convex portions of the caulking projections that fix the core pieces are arranged so as to be displaced in the circumferential direction by the desired skew amount. Since they are stacked in a skewed state, and the caulking projections are elongated in the radial direction of the lamination core, even if the pole plate surface is narrow like the rotor of a small electric motor, The caulking projections can be formed in a state where the necessary crimping area is secured along the surface, and sufficient caulking strength can be obtained. Further, the progressive die device of the present invention, compared to the conventional die device of this type, the relative position of the punch and the die in the forming process of the caulking protrusion is circumferentially divided by the amount of skew per iron core piece. Disposing them in a staggered manner and rotating the die each time new punching is performed in the outer shape punching process to displace the core pieces that have already been stacked in the circumferential direction and form the recesses of the caulking protrusions of the core pieces that are vertically adjacent to each other. The above skew laminated core can be easily manufactured with a simple configuration in which only a rotation imparting device for providing alignment with the convex portion is provided.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a skew laminated core for a rotor and a mold device for manufacturing the same according to the present invention.

FIG. 2 is a plan view of the skew laminated core in FIG.

3 is an enlarged plan view of a main part of FIG.

FIG. 4 is a plan view of a skew laminated core for a rotor according to a conventional example.

5A is an enlarged cross-sectional view of the main part of FIG. 4, and FIG.
Is also a plan view.

[Explanation of symbols]

 1 Upper mold 2 Lower mold 3a 4a 5 Punch 3b 4b 6 Die 7 Squeeze ring 8 Spinning device 10 Laminated iron core 11 12 13 14 1n Iron core piece 11a Measuring through hole 15 Caulking protrusion 15a (Caulking protrusion) Recessed portion 15b ( Convex part of caulking protrusion W Strip-shaped thin plate material (strip material) F Feed direction A Stroke hole punching process B Shaft hole punching process C Caulking part forming process C1 Measuring through hole punching process C2 Caulking protrusion forming Process D Outline punching and stacking caulking process d Skew amount

Claims (2)

[Scope of utility model registration request] 1. Each skew-stacked iron core piece has a caulking protrusion extending in a radial direction, the caulking protrusion forming a concave portion on the upper surface side and a convex portion on the lower surface side, and the caulking protrusion includes a concave portion and a convex portion. Are arranged with a desired skew amount in the circumferential direction,
It is characterized in that the recesses of the caulking projections of the lower iron core piece and the projections of the caulking projections of the upper iron core piece, which are laminated vertically adjacent to each other, are caulked in a fitted state in which they are aligned in the circumferential direction. Skew laminated iron core for rotor. 2. Before the outer shape punching step of sequentially crimping each press-molded core piece in a laminated state simultaneously with the outer shape punching, a recess is formed on the upper surface side elongated in the radial direction with respect to each iron core piece. A forming process for the caulking protrusions is provided to form each convex portion on the lower surface side. In the forming process for the caulking protrusions, punching is performed in a circumferentially offset position relative to the die by the skew amount per iron core piece. In the outer shape punching step, the die side is rotated in the circumferential direction by the skew amount per one iron core piece to newly punch the concave portion of the caulking projection of the lower iron core piece already laminated. A progressive feeding die device for manufacturing a skew laminated iron core for a rotor, characterized in that a rotation imparting device for aligning with a convex portion of a caulking projection of an upper core piece to be pulled out is provided.