JP2005065457A - Contour punching method of motor core and metal mold device for manufacturing the motor core - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contour punching method that prevents the warpage of a product that is generated when the product is subjected to contour punching, and a metal mold device for manufacturing the motor core. <P>SOLUTION: The metal mold device is characterized in that a presser hole 7 is punched outside a product contour 2 by the cooperation of a contour forming punch 12 that punches the product contour 2 from a core material 6, a contour punching die 15, and a presser hole punching die 18; a presser hole forming punch 17 that locks and holds the core material 6 in a state of being inserted in the presser hole 7 is provided to the metal mold device; and the tip of the contour forming punch 12 is set in a position that is retreated from the tip of the presser hole forming punch 17 by a prescribed length X. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an outer punching method for a motor core that prevents warping of a product when the outer shape is punched, and a mold apparatus for manufacturing the motor core, and in particular, a width of a meat portion between an outer periphery of a product to be outer punched and a machining hole inside the product. This method can be applied to a case where there is little or a case where there are few bridges between machined holes inside the product.

A motor core that is an object of implementation of the present invention has a structure called a so-called magnet motor in which a permanent magnet is incorporated in a rotor core, such as a rotor (rotor) of an inner rotor type electric motor. And the one disclosed in Patent Document 2.
JP-A-7-99745 JP-A-9-46946

  In these motor cores, the width of the flesh between the outer periphery of the product to be externally punched and the machined hole inside the product is small, and there are few bridges between the machined holes inside the product. There is a problem that warpage occurs in the product when the outer shape punching of the product is performed, and the cause is that while the outer shape punch is lowered and abuts against the iron core material, the cutting edge bites in and forms a shear surface When processing, it is mentioned that an iron core material is drawn and punched by an external punch.

  For this reason, the moment acting on the punched iron core material (product) causes warpage (curvature) away from the bottom surface of the punching punch, and this warpage hinders the stacking of iron cores. At the same time, since the performance and value of the laminated core product are lowered, a processing method called “precision punching method” as shown in FIGS. 1 and 2 has been adopted as means for preventing warpage.

  In this precision punching method, punching is performed while pressing the iron core material W from both the upper and lower surfaces by a mold device, but the iron core material W is removed from the punch P on the upper die side by a stripper (plate presser) S as shown in FIG. A reverse pressing member H is disposed in the die D on the lower die side so as to face the punch P. The reverse pressing member H supports the iron core material W with a supporting force weaker than that of the punch P, and a stripper S. 2 is formed with an acute-angled annular projection (ring tooth) Sa on the outer side of the outer diameter of the punch P, and is punched in a process as shown in FIG.

  The stripper S is lowered as shown in FIG. 2 (a), and the punch P as shown in FIG. 2 (b) with the ring tooth Sa biting into the iron core material W whose lower surface is supported by the die D and the reverse pressing member H. 2, while pressing down the reverse pressing member H, the core material W sandwiched between the stripper S and the die D is sheared, and the core C is punched from the core material W as shown in FIG. 2D, the stripper S, the punch P, and the iron core material W are lifted as shown in FIG. 2D, and the reverse presser member H is lifted as shown in FIG. Knockout of iron core C from D.

  As described above, in the precision punching method, the outer side of the product (iron core C) to be punched with respect to the iron core material W is forcibly pressed by the ring teeth Sa formed on the lower surface of the stripper S and the product to be punched (iron core C) is pressed. By punching in a state where the lower surface is supported by the reverse pressing member H, it is possible to prevent the core material from being drawn when the outer shape is punched by the punch P, and thus it is possible to achieve precise punching without the influence of warpage.

  However, in the case of the precision punching method, a reverse pressing member H which is not necessary for punching a normal laminated iron core is specially arranged in the die D as a die device, and a stripper S, that is, a plate presser, is usually used. Since the annular tooth portion Sa which is not necessary for punching the laminated core is provided, the structure of the mold apparatus is complicated as a whole, resulting in an increase in cost, and a mold apparatus for punching a normal laminated core. There was a problem that perfect compatibility could not be achieved.

  Accordingly, the present invention provides a motor core outer shape punching method and a mold apparatus for manufacturing the motor core that can solve the above-described problems of the prior art, and in particular, an ordinary motor core that has no fear of being drawn in the core material. By making slight modifications to the punching method and the mold device for manufacturing it, it is possible to achieve precise punching that eliminates the effects of warpage and to achieve almost perfect compatibility with ordinary motor cores. The main purpose is to provide a simple and inexpensive method and apparatus.

  The outer punching method of the motor core according to the present invention is a method of punching a press hole outside the outer shape of a product with a press hole punch and a press hole punching die immediately before punching the product outer shape from the core material with an external punch and an external punch die. The outer shape of the product is punched out in a state where the iron core material is locked and held by the press hole punch, and the iron core material is equidistant from the product outer shape at at least three positions at equal intervals. It is possible to adopt a form that is locked and held by.

  The mold apparatus for manufacturing a motor core according to the present invention is formed by punching a pressing hole in cooperation with a punching die and an outer punching die for punching a product outer shape from a core material, and a pressing hole punching die outside the outer shape of the product. A punching punch for holding and holding the iron core material in a state of being inserted into the hole is provided, and the outer punching is set at a position retracted by a predetermined length from the tip of the pressing hole punching punch, The press hole punching punch can take a form in which at least three or more positions are provided at equal distances from the outer punching punch.

  In the outer punching method of the motor core according to the present invention, by punching the outer shape of the product while holding and holding the iron core material with the presser punch, the material pulling action by the outer punch is suppressed when punching the outer shape of the product. This makes it possible to achieve precise punching that eliminates the influence of warpage on the core plate that is the product.

  Further, in this outer shape punching method, it is more desirable that the holding of the iron core material by the presser punching punch is equally performed at as many positions as possible at equal distances from the outer shape of the product, but in consideration of cost. In some cases, practical use is possible by locking and holding at least three places, and about six places are practical as in the embodiment.

  In the mold apparatus for manufacturing the motor core according to the present invention, the punching punch for holding and holding the iron core material in the state of being inserted into the pressing hole operates prior to the outer punching punch. The material punching action by the external punching punch is suppressed, and this can achieve precise punching that eliminates the influence of warpage on the product iron core plate, but this punching punch mechanism is a press punch punching punch to the normal punching punch mechanism. It is a simple structure with only a die added.

  Therefore, the same function can be achieved at a lower cost and the outer shape of the product can be punched as compared with the conventional precision punching method in which a reverse pressing mechanism is added in the die or an annular tooth portion is provided in the stripper. Since the punch mechanism for performing the same structure as that of the ordinary punching mechanism, the punched iron core plate can be punched into the die and stacked as in the case of the ordinary punching mechanism.

  The outer punching method of the motor core of the present invention and the mold apparatus for manufacturing the same will be described in detail with reference to the accompanying drawings showing a preferred embodiment in which the present invention is applied to a rotor core of a magnet motor. Fig. 4 is a plan view showing an example of a rotor core of a magnet motor that is an object of the invention, Fig. 4 is a layout diagram of an outer shape punching process part, and Fig. 5 is a progressive feed by an upper die and a lower die for performing outer shape punching. The principal part longitudinal cross-sectional view in the last process of a type | mold apparatus is shown.

  As shown in FIG. 3, the rotor iron core 1 has a shaft hole 3, a plurality of permanent magnet insertion holes 4, and air holes 5 pre-punched in the product outer shape 2, and the product is processed at the outer shape punching process portion which is the final process. Although the outer shape 2 is sheared, the width (bridge) a of the product outer shape 2 and the end portion of the permanent magnet accommodation hole 4 is narrow, and the bridge b between the adjacent permanent magnet accommodation holes 4 and 4 is also narrow. Therefore, when the product outer shape 2 is punched, the surrounding iron core material portion is drawn into the product outer shape 2 side, and there is a possibility that warping (curvature) occurs.

  In order to prevent this, as shown in FIG. 4, the iron core material 6 has equidistant outer sides of the product outer shape 2, and at least three (6 in the drawing) holding holes 7 are equally spaced (60 in the drawing). The punch hole is punched into each holding hole 7 immediately before the punching shearing of the product outer shape 2 is started, and the punching punch is inserted into each holding hole 7 to hold the core material 6 in a locked state. If punching is performed on the product outer shape 2 in this state, the outer core material portion is not drawn into the product outer shape 2 side, and warpage (curvature) can be prevented.

  As shown in FIG. 5, a manufacturing die apparatus 8 for carrying out the outer punching method of the motor core includes an upper mold side 8A mounted on the ram side (not shown) of the press machine and a table (see FIG. (Not shown) A lower mold side 8B set on the upper mold side 8A and a lower mold side 8B, a belt-shaped iron core material (strip material) 6 is interposed between the upper mold side 8A and the lower mold side 8B. The shaft hole 3, the plurality of permanent magnet insertion holes 4, the air holes 5, and the like have been previously punched in the portion of the material 6 to be punched as the product outer shape 2.

  The manufacturing mold apparatus 8 is provided with an upper mold holder 9, a packing plate 10, a punch plate 11, an outer punch 12, and an upper mold holder 8 on the upper mold side 8 </ b> A so as to be movable up and down ( The lower die side 8B is provided with a lower die holder 14 and a die 16 that is attached to the upper die to form an outer punching die 15 and the like. It is the same as the case of.

  Further, as a configuration peculiar to the present application, on the outside of the outer punching punch 12, six pressing hole punching punches 17 for punching the pressing holes 7 are arranged at equal distances and at equal intervals. Is set at a position retracted by a length X from the front end surface of the press hole punching punch 17, and the press hole punching die 18 is positioned on the die 16 at a position aligned with the press hole punching punch 17 outside the outer punching die 15. Is forming.

  When performing the outer shape punching process, when the upper mold holder 9 of the upper mold side 8A is lowered, the lower surface of the stripper 13 comes into contact with the upper surface of the iron core material 6 and is pushed down to the lower mold side 8B side. When abutting against the upper surface of the die 16, the upper die holder 9 is further lowered while the stripper 13 is still pressing the iron core material 6. First, the presser hole punching punch 17 is pressed against the iron core material 6. In cooperation with 18, punching of the holding hole 7 is started.

  Then, when the upper die holder 9 that continues to descend is lowered by a preset length X, the outer punching punch 12 starts to punch the product outer shape 2 in cooperation with the outer punching die 15. The length X is set in advance so that the pressing hole punching punch 17 is inserted into the iron core material 6 during or after the processing of the pressing hole 7.

  Therefore, when the outer punching punch 12 performs the punching of the product outer shape 2 on the iron core material 6, the iron core material 6 is held and held by the holding hole punching punch 17 on the material portion outside the outer shape 2 of the product. As a result, the iron core material 6 is not drawn into the product outer shape 2 side, and the occurrence of warpage (curvature) can be prevented.

  In the embodiment, the presser hole punching punch and the presser hole punching die are arranged at six locations, but a desired function can be obtained as long as there are at least three or more locations, and the presser hole is in a completely punched state. It is not limited to a half-punched state, and the function can be demonstrated, and it has been applied to the external punching process provided in the final process of the progressive die feeding mold. It is also possible to adopt a form in which a caulking coupling method using a punching projection or the like is used in combination with a die feeding die, and it is also possible to apply not only to a motor rotor core but also to a motor stator core. .

The principal part sectional drawing of the external punching mechanism which implements the precision punching method of a prior art is shown. FIG. 3 is a process diagram of outline punching using the outline punching mechanism of FIG. 1. An example of the iron core for rotors of the magnet motor used as an object of invention is shown with a top view. The layout figure of the external punching process part to which this invention is applied is shown. The principal part longitudinal cross-sectional view of the progressive die apparatus which performs the external punching to which this invention is applied is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Iron core for rotors 2 Product outline 3 Shaft hole 4 Permanent magnet insertion hole 5 Air hole 6 Iron core material 7 Holding hole 8 Manufacturing die apparatus 8A Upper mold side 8B Lower mold side 9 Upper mold holder 10 Packing plate 11 Punch plate 12 Outline Punching punch 13 Stripper 14 Lower die holder 15 External punching die 16 Die 17 Pressing hole punching punch 18 Pressing hole punching die

Claims (4)

  Immediately before punching the outer shape of the product from the core material with an outer punch and outer punch, press the punch hole outside the outer shape of the product with the press hole punch and press hole punch die, and engage the core material with the press hole punch. A method of punching the outer shape of the motor core, wherein the outer shape of the product is punched in a state of being held.   2. The outer punching method for a motor core according to claim 1, wherein the iron core material is held and held by a press punching punch at at least three or more positions at equal distances from the outer shape of the product.   Punching out the outer shape of the product from the core material, punching out the outer punch and outer die, and punching out the holding hole in cooperation with the punching die on the outside of the outer shape of the product, and holding the core material in the state of being inserted into the holding hole A mold apparatus for manufacturing a motor core, comprising a press punching punch, wherein the outer punch is set at a position where the tip is retracted by a predetermined length from the tip of the press punch.   4. The mold apparatus for manufacturing a motor core according to claim 3, wherein at least three of the presser hole punches are provided at equal distances from the outer punch.

Images