JP2007300795A - Laminated iron core - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated iron core excellent in caulking junction strength and profile even if iron core pieces each having a thickness of lower than 0.2 mm are used, and to provide a method of manufacturing the laminated iron core. <P>SOLUTION: The iron core is caulked and laminated so that caulking protrusions 16 each formed on the iron core pieces 18, 19 and having a protrusion length of two times the plate thickness of an iron core 14 are caulked and laminated, so as to enter into through-engaging portions 15 formed on the plurality of iron core pieces 14 sequentially laminated up to the same thickness as the protrusion length and the thickness where the tip of the caulking protrusion 16 reaches, and the forming positions of the caulking protrusions 16 and the through-engaging holes 15 are provided differently per predetermined laminate thickness. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a laminated iron core such as a rotor core and a stator core in which thin plates are laminated.

Conventionally, in order to improve motor output or to improve performance with a small size and light weight, a laminated core with a predetermined thickness obtained by laminating a number of core pieces punched from thin steel plates has been used for the rotor core and stator core. Has been. When laminating a large number of thin core pieces, for example, each core piece is provided with a caulking connection part such as a valley-shaped protrusion or a cut-and-raised protrusion, and the iron core pieces are caulked with each other through this caulking connection part. In other words, each piece was caulked and laminated.

However, when the thickness of the iron core piece is less than 0.2 mm, for example, it is difficult to express sufficient caulking strength in the conventional caulking connection portion such as a single-sheet caulking valley-shaped projection or a cut-and-raised projection. The iron core is separated, and the caulking joint strength between the iron core pieces constituting the laminated iron core is lowered, resulting in problems such as shape deterioration.
This invention is made | formed in view of this situation, For example, even if it uses the iron core piece which has a board thickness of less than 0.2 mm, it aims at providing the laminated iron core which is excellent in crimping joining strength and a shape property.

The laminated iron core according to the present invention that meets the above-mentioned object is a laminated iron core that is caulked and laminated via caulking protrusions and engagement holes formed on the iron core piece, and is formed on the iron core piece and is at least twice the thickness of the iron core piece. The caulking protrusions having a protruding length of 5 mm enter the through-engagement holes formed in a plurality of iron core pieces that are sequentially stacked up to a thickness that is substantially the same as the protruding length or reach the tip of the caulking protrusion. are stacked, the caulking projection and the through-engagement hole provided by changing the formation position of a predetermined lamination each thickness, moreover, the shape of the caulking projections, viewed from the side to trapezoidal, or a multi-stage trapezoid.
By inserting the caulking protrusion into the through-engaging hole, the outer peripheral side of the caulking protrusion is brought into contact with the entire inner peripheral side of each engaging hole provided in the plurality of core pieces constituting the through-engaging hole. Thus, the frictional force between each iron core piece and the caulking protrusion is improved.
In addition, since the position where the caulking protrusion and the through-engagement hole are formed is changed for each predetermined stacking thickness, even if the maximum formation length of the caulking protrusion length is limited, the position where the caulking protrusion and the through-engagement hole are formed is changed. can do.

By making the shape of the caulking protrusion into a trapezoidal shape or a multi-stage trapezoidal shape as viewed from the side, the caulking protrusion can be surely inserted into the through-engagement hole. A caulking projection enters each engagement hole. For this reason, when the caulking protrusion is inserted into the through-engagement hole and caulking force is applied, the outer peripheral side of the caulking protrusion can be reliably brought into close contact with the inner peripheral side of each engaging hole provided in each iron core piece. it can.

In the laminated core according to the present invention, a plurality of recesses or notches are formed on the inner peripheral side of the through-engagement hole, so that the iron core piece can be prevented from blurring.
When a caulking protrusion is inserted into the through-engagement hole and a caulking force is applied, a part of the caulking protrusion is plastically deformed and enters a plurality of recesses or notches formed on the inner peripheral side of the through-engagement hole. , Filling the recess or notch. For this reason, the caulking joint strength is increased. Furthermore, since some of the caulking protrusions are plastically deformed and entered into the recesses or notches, it is possible to restrain free rotation and blurring of each iron core piece.

In the laminated iron core according to any one of claims 1 to 4, the caulking protrusion formed on the iron core piece and having a protruding length that is twice or more the plate thickness of the iron core piece has substantially the same thickness as the protruding length or the tip of the caulking protrusion. Caulking protrusions are formed by entering the through-engagement holes formed in a plurality of iron core pieces that are sequentially laminated to reach the thickness and caulking and stacking, and changing the formation positions of the caulking protrusions and through-engaging holes for each predetermined lamination thickness. Can be caulked with multiple core pieces, and even if the core piece is thin, the frictional force between each core piece and the caulking projection is improved, and a laminated core of any thickness is formed with high caulking joint strength. It becomes possible.

And, since the shape of the caulking protrusion is trapezoidal or multi-stage trapezoidal when viewed from the side, the outer peripheral side of the caulking protrusion is securely inserted into the inner peripheral side of each engagement hole provided in each iron core piece. It can be made to contact and it becomes possible to improve a frictional force.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
Here, FIG. 1 (A) is an explanatory view showing a conceptual structure of a laminated core according to an embodiment of the present invention, and (B) is an explanation showing a conceptual structure of a laminated core according to another embodiment of the present invention. FIG. 2 (A) is an explanatory view showing a conceptual structure of a recess formed on the inner peripheral side of the through-engagement hole of the laminated core according to one embodiment of the present invention, and FIG. Explanatory drawing which shows the conceptual structure of the recessed part formed in the inner peripheral side of the through-engagement hole which concerns on a modification, FIG. 3 is a conceptual structure of the press station used for the manufacturing method of the laminated iron core which concerns on one embodiment of this invention FIG. 4 is an explanatory view showing a procedure for punching out an iron core piece from a thin plate material in the manufacturing method of the laminated core, and FIG. 5 is an explanatory view showing an example of a stator core obtained by the manufacturing method of the laminated core.

As shown in FIG. 1 (A), a laminated core 10 according to an embodiment of the present invention changes the position of caulking and connecting a plurality of iron core pieces for each predetermined lamination, for example, a lower layer laminated portion 11 and an upper layer It has the lamination part 12, and this lamination is repeated for every predetermined lamination. The lower layer laminated portion 11 is formed by laminating iron core pieces 14 formed at predetermined intervals and having rectangular engagement holes 13 in plan view so that the centers of the two engagement holes 13 coincide with each other. The through-engagement hole 15 is formed into a rectangular shape in plan view, trapezoidal in side view, and has a protrusion length twice as large as the thickness of the iron core piece 14 and has a rectangular shape in plan view. The iron core pieces 18 in which the holes 17 are formed at predetermined intervals are punched, and the caulking protrusions 16 are inserted into the through-engagement holes 15 to be laminated.
Further, the upper layer laminated portion 12 is formed by laminating the rectangular engagement hole 13 formed in the iron core piece 14 in plan view with the center of the engagement hole 17 previously formed in the laminated iron core piece 18. The through-engagement hole 15 is formed, and a caulking protrusion 16 having a rectangular shape in plan view and a trapezoidal shape in side view is formed in the through-engagement hole 15 and has a projecting length twice the thickness of the iron core piece 14. The iron core piece 19 is punched out, and the caulking protrusion 16 enters the through-engagement hole 15 and is caulked and laminated.

In addition, a caulking force can be applied to the laminated layers from above and below as needed to increase the caulking bonding force. Since the shape of the caulking protrusion 16 is trapezoidal when viewed from the side, the size of the engagement hole 13 formed in the iron core piece 14 in contact with the iron core pieces 18 and 19 where the caulking protrusion 16 is formed is as follows. , 19 is made larger than the engaging hole 13 formed in the iron core piece 14 that does not directly contact the steel core 14. By doing so, the caulking protrusion 16 can be surely inserted into the through-engagement hole 15.

FIG. 1B shows a laminated core 20 according to another embodiment of the present invention. The laminated core 20 has a lower layer laminated portion 21 and an upper layer laminated portion 22. The lower layer laminated portion 21 is formed at this time by laminating three pieces of iron core pieces 14 formed at predetermined intervals and having rectangular engagement holes 13 in a plan view so that the centers of the engagement holes 13 coincide. The through-engagement hole 23 is rectangular in plan view, trapezoidal in side view, and has a projection length 24 that is three times the thickness of the core piece 14. The core pieces 25 formed at intervals are punched, and the caulking protrusions 24 are inserted into the through-engagement holes 23 to be caulked and laminated.
The upper layer laminated portion 22 is formed in the iron core piece 14 and laminated in a plan view so that the rectangular engagement hole 13 is formed in the iron core piece 25 so as to coincide with the center of the rectangular engagement hole 17 in a plan view. The through-holes 23 are punched out by punching an iron core piece 26 having a rectangular shape in plan view and a trapezoidal shape in side view and having a projection length 24 that is three times the plate thickness of the iron core piece 14. The protrusion 24 is inserted into the through-engagement hole 23 and is caulked and laminated.

Subsequently, with reference to FIG. 2 (A), it described its relationship with the caulking projections 16, 24 and the through engaging holes 15, 23.
The engagement hole 13 formed in the iron core piece 14 has a rectangular shape in plan view, and a concave portion 27 is formed at the center of the rectangular short piece. For this reason, the through-engagement holes 15 and 23 formed in a plurality of laminated bodies in which the core pieces 14 are laminated with the centers of the engagement holes 13 being aligned have a rectangular shape in plan view, and each short side There is a penetrating recess 27a in the center. The caulking projections 16 and 24 provided on the iron core pieces 18, 19, 25, and 26 are caulked into the through-engagement holes 15 and 23, and the caulking projections 16 and 24 are plastically deformed as the caulking force increases. Thus, it comes into contact with the inner peripheral side of the through-engagement holes 15 and 23.

As a result, a frictional force is generated between the outer peripheral surfaces of the caulking projections 16 and 24 that are in contact with the inner peripheral side surfaces of the through engagement holes 15 and 23, and the inner peripheral side of the through engagement holes 15 and 23 and the iron core piece 18. , 19, 25, and 26, and caulking protrusions 16 and 24, and caulking bonding force is generated and integrated. Furthermore, a part of the outer sides of the caulking projections 16 and 24 that are in contact with the short sides of the through-engaging holes 15 and 23 are plastically deformed and enter the through-concave 27a to fill the through-concave 27a. As a result, free rotation is restrained in the caulking projections 16 and 24 that have entered the through-engagement holes 15 and 23. In addition, each iron core piece 14 forming the through-engaging holes 15 and 23 is also restrained from freely rotating because a part of the caulking projections 16 and 24 enters the through-concave 27a. As a result, the caulking joint strength as a laminated iron core is improved and the shape stability is ensured.

Further, a through engagement hole 28 which is a modification of the through engagement hole 15 is shown in FIG. The through-engagement holes 28 have a circular shape when viewed in plan, and a through-concave portion 29 is provided at a position that is symmetrical with respect to the center of the through-engagement hole 28. In the case where the circular through-engagement hole 28 is formed, the shape of the caulking protrusion to enter is preferably a truncated cone shape.
Moreover, although the penetration recessed parts 27a and 29 are formed in two places, not only this but arbitrary numbers, such as three places and four places, can be formed.

Next, the manufacturing method of the laminated iron core which concerns on one embodiment of this invention is demonstrated in detail using FIG. 3, FIG.
FIG. 3 shows a press station 30 for manufacturing the laminated cores 10 and 20. In this embodiment, the press station 30 is provided with a rotor core manufacturing area on the upstream side and a stator core manufacturing area on the downstream side where the thin plate 31 from which the iron core piece is punched is conveyed. The upper mold 32 and the lower mold 33 are connected by a column 34, and a plunger (not shown) that is hydraulically driven is connected to the lower mold 33 so as to move up and down with respect to the upper mold 32. The thin plate 31 is disposed between the upper die 32 and the lower die 33, and the thin plate 31 is intermittently conveyed at a predetermined speed in synchronization with the pressing operation of the upper die 32 and the lower die 33.

The lower die 33, a lower die set 35 which plunger is connected, die plate 36 is provided which is provided on the upper side of the lower die set 35. The upper die 32 includes an upper die set 37 for fixing the upper die 32 to a fixed frame (not shown) of the press station 30, a punch plate 38 fixed to the upper die set 37, and a stripper for holding the thin plate 31 together with the die plate 36. A plate 39 is provided. Further, in the rotor core manufacturing area, punches 41, 42, 43, 44, 45 for rotor core machining and a rotor core punching punch 46 are provided on the punch plate 38 via a punch support plate 40. In the stator core manufacturing area, punches 47, 48, 49, 50, 51 for stator core machining and a stator core punching punch 52 are provided on the punch plate 38 via a punch support plate 40.

Further, the stripper plate 39 includes rotor core processing punches 41, 42, 43, 44, 45, rotor core punching punches 46, stator core processing punches 47, 48, 49, 50, 51, stator core punching punches. Through holes 53 to 64 through which 52 penetrates are respectively provided at corresponding positions. Further, the die plate 36 has die holes 65 to 73 into which punched pieces punched by the punches 41, 42, 43 and 44 for rotor core processing and punches 47, 48, 49, 50 and 51 for stator core processing enter. The lower die set 35 is provided with a discharge port 74 connected to each of the die holes 65 to 73 for discharging punched pieces.

In addition, a bottom plate block 75 connected to a hydraulic cylinder (not shown) is provided immediately below the rotor core punching punch 46 of the lower mold 33, and a die hole for rotor core formed by a die button 76 is provided. Accordingly, the rotor core punched pieces punched by the rotor core punching punch 46 are sequentially laminated in the rotor core die hole. Similarly, immediately below the stator core punching punch 52 of the lower die 33, a bottom plate block 77 connected to a hydraulic cylinder (not shown) is provided, and a stator core die hole formed by a die button 78 is provided. Accordingly, the stator core punched pieces punched by the stator core punch 52 are sequentially stacked in the stator core die hole.

As shown in FIG. 4, when the thin plate 31 in which the guide hole 79 is formed at the upstream station (not shown) is supplied to the rotor core manufacturing area of the press station 30, the central hole 80 for the rotor core is used for processing the rotor core. The engagement hole 81 is formed around the center hole 80 using the punches 42 and 43 for processing the rotor core. Next, the rotor core core pieces 82 are punched out by the rotor core punching punch 46 and are sequentially stacked in the die hole for the rotor core formed by the die button 76.
The thin plate 31 from which the rotor core core piece 82 has been punched is then supplied to the stator core manufacturing area, and slots 83 and pole teeth 84 are formed by the punch 47 for processing the stator core. Further, engagement holes 85 are formed by the punches 49 and 51 for processing the stator core, and the stator core core pieces 86 are punched by the stator core punching punch 52 and are sequentially laminated in the die hole for the stator core formed by the die button 78. Is done.

When a predetermined number (for example, three) of rotor core core pieces 82 and stator core core pieces 86 are laminated in the rotor core die hole and the stator core die hole, respectively, the punch position control provided in the upper die set 37 is controlled. The lowering position of the rotor core machining punch 43 is adjusted by using the lever 87, so that a caulking projection is formed on the rotor core core piece 82 to be extracted next, and the operation of the punch 43 is controlled. The punch 44 is operated by stopping and the engagement hole 81 is formed at a position different from the engagement hole 81 of the previous rotor core core piece 82. Further, by stopping the operation of the punches 49 and 51 for processing the stator core and operating the punches 48 and 50, the engagement cores 86 having different caulking projections and forming positions are formed in the stator core core piece 86 to be extracted next. can do. The rotor core iron core piece 82 and the stator core iron core piece 86 each having an engagement hole formed by changing the caulking protrusion and the formation position are respectively punched and stacked in advance in the rotor core die hole and the stator core die hole. Laminated on each core piece. During the lamination, the rotor cylinder core piece 82 and the stator core that have been previously laminated are obtained by operating or supporting the hydraulic cylinders connected to the bottom plate blocks 75 and 78 from below. Caulking protrusions enter into the through-engaging holes formed in the iron core pieces 86, respectively, and caulking lamination is performed.

When each of the plurality of rotor core core pieces 82 and stator core core pieces 86 laminated in the rotor core die hole and the stator core die hole is caulked, the punch position control lever 87 is adjusted again, Next, the rotor core core piece and the stator core core piece to be punched in a plurality of pieces, only the engagement hole at the position facing the position of the engagement hole formed in the rotor core core piece and the stator core core piece having the caulking projections. To be formed. In this state, a predetermined number of rotor core core pieces and stator core core pieces are punched, and when they are stacked, the lever 87 for punch position control is adjusted again, and the rotor core has caulking protrusions and engagement holes. The core piece and stator core piece are punched out and laminated by caulking. By performing the punching and caulking operations as described above while changing the position of the through-engagement hole for each predetermined number of punches, the rotor core and the stator core having a predetermined thickness are formed. An example of the stator core 88 formed in FIG. 5 is shown. Here, 89 indicates a slot portion, 90 indicates a pole tooth portion, and 91 indicates a caulking portion.

As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment, For example, the formation position of the penetration engagement hole and the crimping protrusion was changed for every 3 and 2 layers. However, the formation positions of the through-engagement holes and the caulking projections can be changed for every other number. Further, the shape of the caulking protrusion is a trapezoidal shape when viewed from the side, but the shape of the caulking protrusion can also be a multistage trapezoidal shape. In this case, it is desirable that the shape of the through-engagement hole as viewed from the side is a multistage trapezoidal shape with the same interval as the caulking projection.
Further, a cutout portion may be provided on the inner peripheral side of the through-engagement hole instead of the recess, and the number of the cutout engagement holes may be two or more.

(A) is explanatory drawing which shows the conceptual structure of the laminated iron core which concerns on one embodiment of this invention, (B) is explanatory drawing which shows the conceptual structure of the laminated iron core which concerns on other embodiment of this invention. (A) is explanatory drawing which shows the conceptual structure of the recessed part formed in the inner peripheral side of the penetration engagement hole of the laminated iron core which concerns on one embodiment of this invention, (B) concerns on the modification of the laminated iron core. It is explanatory drawing which shows the conceptual structure of the recessed part formed in the inner peripheral side of the penetration engagement hole. It is a conceptual structure figure of the press station used for the manufacturing method of the laminated core which concerns on one embodiment of this invention. It is explanatory drawing which shows the procedure which punches out an iron core piece from the thin plate material in the manufacturing method of the laminated iron core. It is explanatory drawing which shows an example of the stator core obtained with the manufacturing method of the same laminated iron core.

Explanation of symbols

10: laminated iron core, 11: lower layer laminated portion, 12: upper layer laminated portion, 13: engagement hole, 14: iron core piece, 15: penetration engagement hole, 16: caulking projection, 17: engagement hole, 18, 19: Iron core piece, 20: laminated iron core, 21: lower layer laminated part, 22: upper layer laminated part, 23: penetration engaging hole, 24: caulking protrusion, 25, 26: iron core piece, 27: recessed part, 27a: penetrating recessed part, 28: Through engagement hole, 29: through recess, 30 press station, 31: thin plate, 32: upper mold, 33: lower mold, 34: support, 35: lower die set, 36: die plate, 37: upper die set , 38: punch plate, 39: stripper plate, 40: punch support plate, 41, 42, 43, 44, 45: punch for rotor core processing, 46: rotor core punch, 47, 48, 49, 50, 51 : Stator Punch for machining, 52: punching punch for stator core, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64: through hole, 65, 66, 67, 68, 69, 70, 71, 72, 73: die hole, 74: discharge port, 75: bottom plate block, 76: die button, 77: bottom plate block, 78: die button, 79: guide hole, 80: center hole, 81: engagement hole , 82: rotor core piece, 83: slot, 84: pole tooth, 85: engagement hole, 86: stator core piece, 87: lever, 88: stator core, 89: slot part, 90: pole tooth part, 91: Caulking part

Claims (4)

In a laminated iron core that is caulked and laminated via caulking protrusions and engagement holes formed on the iron core piece,
A plurality of the caulking protrusions formed on the iron core piece and having a protruding length that is twice or more the plate thickness of the iron core piece are sequentially laminated to a thickness that is substantially the same as the protruding length or a thickness that reaches the tip of the caulking protrusion. A laminated core comprising: a through-engagement hole formed in a piece of iron core, and caulking and laminating, and the formation positions of the caulking protrusion and the through-engagement hole are changed for each predetermined laminating thickness. 2. The laminated core according to claim 1, wherein the caulking protrusion has a trapezoidal shape or a multi-stage trapezoidal shape when viewed from the side. 3. The laminated core according to claim 1, wherein a plurality of recesses or notches are formed on an inner peripheral side of the through-engagement hole to prevent blurring of the core piece. Laminated iron core. In a method for manufacturing a laminated core, in which a caulking protrusion and an engagement hole are provided in an iron core piece, and the caulking protrusion and the engagement hole are caulked and laminated,
A through-engagement hole into which the caulking protrusion enters at a plurality of predetermined positions of the core piece is formed, and the caulking protrusion having a protrusion length that is more than twice the thickness of the iron core piece is inserted into the through-engagement hole. The outer core is formed, the outer shape is removed, the caulking protrusion is inserted into the through-engagement hole, and sequentially stacked, and then the through-hole engaging hole and the caulking protrusion are formed at predetermined positions on the laminated iron core piece. A method for producing a laminated iron core, wherein the laminated iron core is formed by changing the thickness and caulking.

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