JP2015107013A - Method for punching iron core piece used for laminated iron core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for punching an iron core piece, capable of punching and forming an iron core piece having a plurality of projections in an inner peripheral edge or an outer peripheral edge without generating a positional deviation between the projection and the inner peripheral edge or the outer peripheral edge and improving the rotation/lamination speed of the iron core piece.SOLUTION: A method for punching an iron core piece includes a projection removal step of: forming a plurality of projections in a plate using a projection formation punch 74 having blade parts 72 for projections having the number more than that of projections 46 of the iron core piece in order to punch the iron core piece; punching the projections 46 formed by the blade parts 72 for projections at positions corresponding to the blade parts 72 for projections on the plate 52 and displacing a position at which unnecessary projections are punched and removed with the advance of punching to the plate 52.

Description

The present invention relates to a punching method for punching and forming core pieces such as a rotor core piece used for a laminated rotor core in a motor or a stator core piece used for a laminated stator core.

Conventionally, as this type of punching method, for example, a method as disclosed in Patent Document 1 has been proposed. In this conventional method, as shown in FIG. 10, the rotor core piece 92 is continuously punched and formed from the sheet material sheet 91 while the belt-shaped sheet material sheet 91 is fed and moved in the length direction. At this time, a plurality of protrusions 93 are formed on the inner periphery of the rotor core piece 92.

A plurality of punched rotor core pieces 92 are stacked and fixed to each other to form a laminated rotor core for an electric motor. In this case, in order to suppress adverse effects such as a change in flatness and a change in plate thickness of the plate material sheet 91 to the laminated state of the laminated rotor core, a rolling method is adopted. This rolling method is a method of laminating the punched rotor core pieces 92 while displacing the central angle of the rotor core pieces 92 with respect to the other rotor core pieces 92 to cancel the flatness change or the like.

The method for punching the rotor core piece 92 of Patent Document 1 will be further described. First, in the station shown in FIG. 9A, openings 97 having a U-shape for the plurality of protrusions 93 on the inner peripheral side of the rotor core piece 92 are punched out from the plate material sheet 91. . Next, in the station shown in FIG. 9B, the arc portion 98 that defines the inner periphery of the rotor core piece 92 is punched out so as to connect the base end portions of the opening portions 97 adjacent to the plate sheet 91. It is formed.

JP 2013-143793 A

However, in this conventional method, the opening 97 for providing the plurality of protrusions 93 on the inner periphery of the rotor core piece 92 and the arc portion for defining the inner periphery of the rotor core piece 92 as described above. 98 are punched and formed at different stations while the sheet material sheet 91 is fed and moved. For this reason, position shift arises in the process part with respect to the board | plate material sheet 91 between both stations, and the positional accuracy of the protrusion 93 and the circular arc part 98 worsens. Further, there is a possibility that the arc portion 98 is not formed by being connected to the proximal end portion of the adjacent opening 97. In such a case, the rotor core piece 92 cannot be separated from the plate material sheet 91 and is temporarily separated. Even if it is possible, burrs are formed, which hinders subsequent processes.

The present invention has been made paying attention to such problems existing in the prior art. The purpose is to punch and form an iron core piece having a plurality of protrusions on the inner peripheral edge or the outer peripheral edge without causing a positional shift between the protrusion and the inner peripheral edge or the outer peripheral edge. An object of the present invention is to provide a method of punching an iron core piece that can improve the rolling speed.

In order to achieve the above-mentioned object, the present invention punches out an iron core piece having one or more protrusions formed on the inner edge or the outer edge from a thin plate-like plate material, and the iron piece is separated from other iron pieces. In the punching method of the iron core piece to be rolled up, in order to punch out the iron core piece, a protrusion forming punch having a larger number of protrusion blade portions than the protrusions of the iron core piece is used, and the protrusion forming punch is used. After forming a plurality of protrusions on the plate material, a protrusion removing step of punching out the protrusion formed by the protrusion blade portion at a position corresponding to the protrusion blade portion on the plate material The protrusion removing step is characterized by displacing a position where an unnecessary protrusion is punched and removed as the punching of the plate material proceeds.

Further, in the above method, as the protrusion forming punch, a number of protrusion blade portions that are multiples of the protrusion of the iron core piece are formed.

In the above method, the core pieces are stacked to form a rotor of the motor, and the protrusion is formed on the inner periphery, and the protrusion is inserted into the inner periphery of the rotor. It is good to engage with the groove part in the outer periphery of a rotating shaft.

In the above method, the core pieces are stacked to become a stator of the motor, and the protrusion is formed on the outer peripheral edge, and the protrusion is fixed to the motor case. .

In the above-described method, it is preferable to punch out both the iron core piece as the motor rotor and the iron core piece as the motor stator from the same plate material.

As described above, according to the present invention, an iron core piece having a plurality of protrusions on the inner peripheral edge or the outer peripheral edge can be punched and formed without causing a positional shift between the protrusion and the inner peripheral edge or the outer peripheral edge. Moreover, the effect of improving the rolling speed of the iron core piece is exhibited. In addition, since only the base of the protrusion is selectively punched and removed in the protrusion removal step, an effect of preventing the residue from being raised by the punched protrusion is less likely to occur.

The partially broken front view which shows roughly one Embodiment of the processing system which actualized this invention to the rotor core piece of an electric motor, and the punching method of a stator core piece. The top view which shows the processing state of the board | plate material in the 1st station in the processing system of FIG. The top view which shows the processing state of the board | plate material in the 2nd station in the same processing system. The top view which shows the processing state of the board | plate material in the 3rd station in the same processing system. The top view which shows the processing state of the board | plate material in the 4th station in the same processing system. The top view which shows the processing state of the board | plate material in the 5th station in the same processing system. The top view which shows the processing state of the board | plate material in the 6th station in the same processing system. The perspective view which shows the state which comprised the lamination | stacking rotor core and the lamination | stacking stator core, respectively by lamination | stacking of the several rotor core piece and the stator core piece which were stamped and formed. The top view which shows the processing state of the board | plate material in the punching method of the conventional rotor core piece. The top view which shows the rotor core piece punched and formed by the conventional punching method.

Hereinafter, an embodiment in which the present invention is embodied in a method of punching a rotor core piece for manufacturing a laminated rotor core of an electric motor and a method of punching a stator core piece for manufacturing a laminated stator core Will be described with reference to FIGS.

First, a rotor core piece and a stator core piece as iron core pieces punched and formed by the punching method of this embodiment, and a configuration of a laminated rotor core and a laminated stator core configured by laminating those core pieces Will be described.

As shown in FIG. 8 (a), the laminated rotor core 31 of the electric motor is in a state in which a large number of rotor core pieces 32 are rolled up, that is, the phase is set at a predetermined angle with respect to other adjacent rotor core pieces 32. (In this embodiment, 180 degrees) It is configured by rotating and fixing each other in a stacked state. The rotor core piece 32 is formed in a thin disc shape by a magnetic steel plate such as a silicon steel plate, and a shaft hole 33 for inserting and fixing a rotation shaft (not shown) is formed at the center thereof. A plurality of (in the embodiment, a pair) key-shaped protrusions for positioning and fixing the laminated rotor core 31 to the rotation shaft by engaging with a groove (not shown) on the rotation shaft on the inner peripheral edge of the shaft hole 33. 34 are formed with an interval of 180 degrees.

As shown in FIG. 8B, the laminated stator core 41 of the electric motor is in a state where a large number of stator core pieces 42 are rolled, that is, the phase is set at a predetermined angle with respect to the other adjacent stator core pieces 32. (In this embodiment, 180 degrees) It is configured by rotating and fixing each other in a stacked state. The stator core piece 42 is formed in a thin disk shape by a magnetic steel plate such as a silicon steel plate, and an accommodation hole 43 for rotatably accommodating the laminated rotor core 31 is formed at the center thereof. . A plurality of winding slots 44 are formed at equal angular intervals in the inner peripheral portion of the accommodation hole 43, and a plurality of magnetic pole portions 45 are formed between the slots 44. An exciting coil (not shown) is wound around the magnetic pole portion 45. A plurality (three in the embodiment) of protrusions 46 are formed at equal intervals on the outer peripheral edge of the stator core piece 42, and through holes (not shown) are formed in these protrusions 46. And the lamination | stacking stator core 41 is fixed to the said case etc. which are not shown in figure with the volt | bolt etc. which pass the through-hole 47 of the protrusion 46. FIG.

Next, a processing system for punching and forming the rotor core piece 32 and the stator core piece 42 and a punching method by the processing system will be described. As shown in FIG. 1, in this processing system 51, six stations of a first station A to a sixth station F are arranged in parallel. A sheet-like sheet material sheet 52 made of a magnetic steel sheet is intermittently fed and moved in the length direction, and sequentially passes through the first to sixth stations A to F.

In this case, pilot holes (not shown) are formed at predetermined intervals on both side portions in the width direction of the plate material sheet 52 by a punching punch device (not shown) at a station (not shown) provided in front of the first station A. And based on this pilot hole, the predetermined process site | part on the board | plate material sheet | seat 52 is positioned in the position corresponding to each station AF. First, in the first station A to the third station C in the previous process, the rotor core pieces 32 are formed by punching from the sheet material sheet 52, and in the fourth station D to the sixth station F in the subsequent process, the remaining originals are formed. A stator core piece 42 is punched out from the material sheet 52.

Therefore, the first station A to the third station C and the punching method of the rotor core piece 32 for punching out the rotor core piece 32 in the processing system 51 will be described in detail.

As shown in FIGS. 1 and 2, the first station A includes a substantially columnar protrusion forming punch 59 for simultaneously punching and forming the shaft hole 33 and the protrusion 34 of the rotor core piece 32, A protrusion forming die 60 corresponding to the protrusion forming punch 59 is provided. On the outer peripheral surface of the protrusion forming punch 59, a plurality of groove-shaped protrusion blade portions 61 for forming the protrusion 34 are formed at equiangular intervals. In this case, the number of protrusion blade parts 61 is configured to be a multiple of the number of protrusions 34 of the rotor core piece 32. That is, in this embodiment, since the number of the protrusions 34 is two, the multiple four blade parts 61 for protrusions are formed at an angular interval of 90 degrees.

As shown in FIGS. 1 and 3, the second station B is formed along the shaft hole 33 at the center of the rotor core piece 32 and the inner peripheral edge position of the shaft hole 33 in the first station A. A plurality of movable punches 57a and 57b for punching and removing unnecessary protrusions of the plurality of protrusions and a die 58 corresponding to the movable punches 57a and 57b are provided. The movable punches 57a and 57b and the die 58 have a similar cross-sectional shape that is the same as or slightly larger than the planar shape of the protrusion 34 provided on the inner peripheral edge of the shaft hole 33 of the rotor core piece 32. Is formed. The plurality of movable punches 57a, 57b and the die 58 are arranged at predetermined angular intervals on the same circumference, and the number of the movable punches 57a, 57b and the die 58 is the number of protrusions 34 on the rotor core piece 32. It is configured to be a multiple of the number of. That is, in this embodiment, since the number of the protrusions 34 is two, the multiple movable punches 57a and 57b and the die 58 that are multiples of the protrusions 34 are arranged at an angular interval of 90 degrees.

First, as shown in FIG. 3 (a), the processing sites on the plate material sheet 52 in which the plurality of protrusions 34 are punched and formed in the first station A are the movable punches 57a and 57b and the die 58 of the second station B. The pair of movable punches 57a are reciprocated with respect to the die 58 in a state of being disposed between the two. By this reciprocation, the protrusions 34 formed at the first station A are punched and removed at an interval of 180 degrees.

Subsequently, as shown in FIG. 3B, the subsequent processing sites on the plate material sheet 52 in which the plurality of protrusions 34 are punched and formed in the first station A are the movable punches 57a and 57b of the second station B. The remaining pair of movable punches 57b are reciprocated with respect to the die 58 in a state of being disposed between the die 58 and the die 58. By this reciprocation, the protrusions 34 formed at the first station A are punched and removed at an interval of 180 degrees.

In this way, in the second station B, the movable punch 57a is provided at a position displaced 90 degrees from the position of the movable punch 57b, and the pair of movable punches 57a is moved while the plate sheet 52 is intermittently fed and moved by a predetermined pitch. And the remaining pair of movable punches 57b are alternately operated. By this operation, the protrusions are alternately punched and removed so that the phases of the protrusions differ by 90 degrees.

As shown in FIGS. 1 and 4, the third station C includes a cylindrical blank punch 63 for punching and forming the outer periphery 62 of the rotor core piece 32, and a die 64 corresponding to the blank punch 63. Is provided. Then, the blank punch 63 is reciprocated with respect to the die 64, and as shown in FIG. 4, the outer periphery 62 of the rotor core piece 32 is formed, and the disc-shaped rotor core piece 32 is punched out from the plate material sheet 52. It is.

Next, the punched rotor core piece 32 is relatively set to a predetermined angle R1 (90 degrees in the embodiment) in one direction or the opposite direction with respect to another rotor core piece 32 adjacent in the stacking direction in the mold. ) Rotated and stacked. And this laminated body is strongly pressed in the laminating direction by a press (not shown) inside or outside the mold, for example, and the rotor core pieces 32 are brought into close contact with each other and held in close contact by caulking (not shown). In this way, the rotor core pieces 32 are rolled and the laminated rotor core 31 is formed. Further, as other fixing means, welding, adhesion, or the like may be used.

Thus, the rotor core pieces 32 formed with the projections 34 on the plate material sheet 52 are alternately punched and rotated in the opposite direction by 90 degrees and stacked, that is, by rolling. The protrusions 34 on the inner peripheral edge of the rotor core piece 32 are arranged at the same position in an aligned state to constitute a laminated rotor core 31 as shown in FIG. Thereafter, a rotating shaft (not shown) is inserted into the shaft hole 33, the protrusion 34 of the shaft hole 33 and the groove portion of the rotating shaft are fitted, and the rotating shaft is fixed to the laminated rotor core 31.

As described above, when the positions of the movable punches 57a and 57b are moved radially outward to invalidate the formation of the protrusions 34, the protrusions are formed on the inner periphery of the shaft hole 33 of the rotor core piece 32. Although a step is formed at a position where the formation of 34 is invalidated, the step does not participate in fixing the laminated rotor core 31 and the rotating shaft, and therefore stress does not concentrate on the step. Further, when the positions of the movable punches 57a and 57b are moved inward in the radial direction, a part of the protrusion 34 remains on the inner periphery. In this case, a cutting process such as shaving is performed before the third station C. It can be solved by inserting.

Next, the 4th station D-the 6th station F for punching out the stator core piece 42 in the said processing system 51 are demonstrated in detail. In addition, the laminated stator core 41 shown in FIG. 8B has a housing hole 43 for rotatably housing the laminated rotor core in the center thereof, and a plurality of windings on the inner peripheral portion of the housing hole 43. The wire slot 44 and a plurality of magnetic pole portions 45 are formed between the slots 44. However, since they are formed by well-known punching, the receiving hole 43, the slot 44, and the magnetic pole portion 45 are located before the fourth station. The detailed description is omitted.

As shown in FIGS. 1 and 5, the fourth station D includes a plurality of protrusion forming punches 74 arranged in a ring at regular intervals to punch out the protrusions 46 of the stator core piece 42. A protrusion forming die 75 corresponding to the protrusion forming punch 74 is provided. On the outer peripheral surface of the protrusion forming punch 74, a plurality of convex groove-shaped protrusion blades 72 for forming the protrusion 46 are formed at equal angular intervals. In this case, the number of protrusion blade portions 72 is configured to be a multiple of the number of protrusions 46 of the stator core piece 42. That is, in this embodiment, since the number of the protrusions 46 is three, the multiple six protrusion blade parts 72 are formed with an angular interval of 60 degrees.

On the base side of the protruding blade 72, an outer peripheral blade 73 that forms a part of the outer periphery of the stator core piece 42 is continuously formed. Since the outer peripheral blade portion 73 and the protruding portion blade portion 72 are formed integrally with the protruding portion forming punch 74, the positional deviation between the protruding portion 46 and the outer periphery continuous to both base portions of the protruding portion 46 is eliminated. Can do. The peripheral length of the outer peripheral blade portion 73 is not particularly limited as long as the adjacent outer peripheral blade portions 73 are connected by the plate material sheet 52.

As shown in FIGS. 1 and 6, the fifth station E is punched with unnecessary protrusions of the plurality of protrusions formed along the outer peripheral edge position of the stator core piece 42 in the fourth station D. A plurality of movable punches 76a and 76b for removal and a die 77 corresponding to the movable punches 76a and 76b are provided. The movable punches 76a and 76b and the die 77 are formed to have a similar cross-sectional shape that is the same as or slightly larger than the planar shape of the protrusion 46 provided on the outer peripheral edge of the stator core piece 42. . The plurality of movable punches 76 a and 76 b and the die 77 are arranged at predetermined angular intervals on the same circumference, and the number of the movable punches 76 a and 76 b and the dies 58 is the number of protrusions 46 on the stator core piece 42. It is configured to be a multiple of the number of. That is, in this embodiment, since the number of the protrusions 46 is three, the multiple six movable punches 76a and 76b and the die 77 are arranged at an angular interval of 60 degrees.

Then, as shown in FIG. 6A, the processed portion on the plate material sheet 52 in which the plurality of protrusions 46 are punched and formed in the fourth station D is the movable punches 76a and 76b and the die 77 of the fifth station E. The pair of movable punches 76a is reciprocated with respect to the die 77 in a state of being disposed between the two. By this reciprocation, the protrusions 46 formed at the fourth station D are punched and removed at intervals of 120 degrees.

Subsequently, as shown in FIG. 6B, the subsequent processing sites on the plate material sheet 52 in which the plurality of protrusions 46 are punched and formed in the fourth station D are movable punches 76a and 76b of the fifth station E. The remaining pair of movable punches 76 b are reciprocated with respect to the die 77 while being disposed between the die 77 and the die 77. By this reciprocation, the protrusions 46 formed at the fourth station D are punched and removed at intervals of 120 degrees.

In this way, in the fifth station E, the movable punch 76a is provided at a position displaced by 60 degrees from the position of the movable punch 76b, and the pair of movable punches 76a is moved while the plate material sheet 52 is intermittently fed and moved by a predetermined pitch. And the remaining pair of movable punches 76b are operated alternately. By this operation, the protrusions are alternately punched and removed so as to be 60 degrees out of phase.

As shown in FIGS. 1 and 7, the sixth station F includes a cylindrical blank punch 79 for punching and forming the outer periphery 78 of the stator core piece 42, and a blank die 80 corresponding to the blank punch 79. And are provided. Then, the blank punch 79 is reciprocated with respect to the blank die 80, and as shown in FIG. 7, the outer periphery 78 of the stator core piece 42 is formed, and the disc-shaped stator core piece 42 is formed from the plate material sheet 52. Punched out.

Next, the stamped stator core piece 42 is relatively fixed to a predetermined angle R2 (60 degrees in the embodiment) in one direction or the opposite direction with respect to another stator core piece 42 adjacent in the stacking direction in the mold. ) Rotated and stacked. And this laminated body is strongly pressed in the laminating direction by a press (not shown) inside or outside the mold, for example, and the stator core pieces 42 are brought into close contact with each other, and held in a crimped state (not shown). In this manner, the stator core pieces 42 are rolled to form the laminated stator core 41. Further, as other fixing means, welding, adhesion, or the like may be used.

In this way, the stator core pieces 42 formed with the protrusions 46 on the plate material sheet 52 are alternately punched and rotated and rotated in opposite directions by 60 degrees, that is, by being rolled up, The protrusions 46 on the outer peripheral edge of the stator core piece 32 are arranged at the same position in an aligned state to constitute a laminated stator core 41 as shown in FIG. Thereafter, the laminated stator core 41 is assembled to a motor case (not shown).

As described above, when the positions of the movable punches 76a and 76b are moved radially inward to invalidate the formation of the protrusions 46, they are overlapped with the outer periphery formed by the outer peripheral blade portion 73 and directed inward. Although a step is formed, this step portion is not involved in the assembly of the laminated stator core 41 and the case, so stress does not concentrate on the step portion. In addition, when the positions of the movable punches 76a and 76b are moved radially outward, a part of the protrusion 46 remains on the outer periphery. In this case, a cutting process such as shaving is inserted in front of the fifth station E. By doing so, the step can be eliminated.

Similarly, it is preferable that the punching of the outer periphery 78 of the stator core piece 42 at the sixth station F is also formed so that a step is formed inward from the outer periphery formed by the outer peripheral blade portion 73. As a result, stress is not concentrated on the stepped portion due to the assembly with the case.

(Example of change)
In addition, this embodiment can also be changed and embodied as follows.
In the embodiment, the rotor core piece 32 and the stator core piece 42 are punched out from another plate material sheet 52.
In the above-described embodiment, when the rotor core piece 32 is formed by punching, a step of forming a storage hole for inserting the permanent magnet is provided in front of the outer peripheral punching station of the rotor core piece 32 to form a storage hole for inserting the permanent magnet. Stamping and forming the rotor core pieces.
In the embodiment, the protrusion blades 61 and 72 for punching and removing the protrusions 34 and 46 are provided twice as many as the protrusions 34 and 46, respectively. Even in the case of a configuration in which the portion is an integral multiple of 3 times or more than the protrusion, or a non-integer multiple such as 1, 5 times, the rotor core piece 32 and the stator core piece 42 at the time of transposition By adjusting the rotation angle, the protrusions can be aligned.
-Rolling may be performed for each of a plurality of sheets, in which case the movable punches 57a, 57b and 76a, 76b operate alternately each time a plurality of core pieces are punched.
In the above embodiment, the inner rotor type rotor core piece and the stator core piece have been described. However, the outer rotor type rotor core piece and the stator core piece can be similarly embodied. . In that case, the rotor core piece has a protrusion formed on the outer peripheral edge, and the protrusion is engaged with the groove portion on the inner periphery of the rotation shaft of the motor inserted through the outer periphery of the rotor formed by stacking the rotor core pieces. Will match. In addition, the stator core piece is formed when the protrusion is formed on the inner peripheral edge, and the protrusion is used to fix the stator formed by stacking the stator core pieces to the motor case.

DESCRIPTION OF SYMBOLS 31 ... Laminated rotor core, 32 ... Rotor core piece, 34 ... Projection, 41 ... Laminated stator core, 42 ... Stator core piece, 46 ... Projection, 51 ... Processing system, 52 ... Sheet material sheet, 57a, 57b ... movable punch for removing protrusions, 58 ... die for removing protrusions, 59 ... projection forming punch, 60 ... projection forming die, 61 ... projection blade part, 62 ... outer periphery, 63 ... blank punch, 64 ... Blank die, 72 ... Projection blade part, 73 ... Peripheral blade part, 74 ... Projection formation punch, 75 ... Projection formation die, 76a, 76b ... Movable punch for projection removal, 77 ... Projection Die for removal, 79 ... blank punch, 80 ... blank die

Claims (5)

In the punching method of an iron core piece, a core piece having one or more protrusions formed on the inner peripheral edge or the outer peripheral edge is punched from a thin plate material, and the core piece is rolled onto another iron core piece. In order to punch out a piece, using a protrusion forming punch having a larger number of protrusion blade portions than the protrusion of the iron core piece, after forming a plurality of protrusions on the plate material by the protrusion forming punch, A protrusion removing step of punching out the protrusion formed by the protruding blade portion at a position corresponding to the protruding blade portion on the plate material, and the protrusion removing step is a process of punching the plate material A method for punching an iron core piece, characterized by displacing a position for punching and removing unnecessary protrusions. The punching method of an iron core piece according to claim 1, wherein the protruding portion forming punch is formed with a number of protruding blade portions that are multiples of the protruding portion of the iron core piece. The core pieces are laminated to form a rotor of a motor, and the protrusion is formed on an inner periphery, and the protrusion is an outer periphery of a rotation shaft of a motor inserted through the inner periphery of the rotor. The iron core piece punching method according to claim 1, wherein the iron core piece is engaged with a groove portion of the iron core piece. The iron core pieces are stacked to form a stator of the motor, and the protrusion is formed on the outer peripheral edge, and the protrusion is used when fixing the stator to the motor case. The punching method of the iron core piece of Claim 1 or 2 characterized by these. 5. The method of punching an iron core piece according to claim 4, wherein both the iron core piece serving as a motor rotor and the iron core piece serving as a motor stator are punched from the same plate material.

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