JP2017127059A - Method for detecting warpage of laminated steel sheet for motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for detecting warpage of a laminated steel sheet for a motor, with which a magnitude of the warpage is accurately detected.SOLUTION: The method for detecting warpage caused by press working of a laminated steel sheet for a motor includes: steps (ST2, ST3) of press-working a steel sheet (W1) having position confirmation holes (W1a) arranged at a predetermined interval; a step of imaging the pressed steel plate (W1); and a step (ST 24) of calculating magnitude of warpage of the pressed steel sheet (W1) on the basis of an amount of deviation (Z1) between a position of the position confirmation hole (W1a) in the picked-up image and a position (W0a) of the position confirming hole before pressing.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for detecting warpage of a laminated steel sheet for motors.

  There are laminated steel plates that constitute the core of the motor. Patent Document 1 discloses a structure that suppresses the occurrence of warpage of a laminated steel sheet.

JP 2014-155368 A

  A laminated steel plate can be formed by laminating a plurality of press products formed by punching from one steel plate or by work hardening.

  The inventor of the present application has noticed that the difference due to the part of a single steel sheet, for example, the thickness, etc. affects the warp size of a single press product, and the warp size of a single press product. Recalling that it is suppressed according to its size. Furthermore, the inventors of the present application have recognized as a problem a method for accurately detecting the magnitude of warpage.

  The method for detecting warpage of a laminated steel sheet for motors according to the present invention accurately detects the magnitude of warpage.

According to the method for detecting warpage of a laminated steel sheet for motors according to the present invention,
A method for detecting warpage caused by press working of laminated steel sheets for motors,
A steel plate having position confirmation holes arranged at predetermined intervals is pressed,
Take an image of the pressed steel sheet,
Based on the amount of deviation between the position confirmation hole position in the captured image and the position confirmation hole position of the steel sheet before press working, the warpage size of the pressed steel sheet is obtained.
According to such a structure, the magnitude | size of curvature can be calculated | required based on the deviation | shift amount of the hole for position confirmation. Therefore, it is possible to determine the magnitude of the warp only by measuring the amount of deviation. Further, since the limited range is measured, the magnitude of the warp can be detected with high accuracy. Furthermore, the curvature of a steel plate can be suppressed according to a site | part by changing the processing conditions of a steel plate according to the magnitude | size of the curvature detected accurately.

  The method for detecting warpage of a laminated steel sheet for motors according to the present invention can accurately detect the magnitude of warpage.

It is the schematic which shows the manufacturing apparatus of the laminated steel plate for motors. It is a schematic diagram which shows 1 process of the manufacturing method of the laminated steel plate for motors which concerns on Embodiment 1. FIG. It is a schematic diagram which shows 1 process of the manufacturing method of the laminated steel plate for motors which concerns on Embodiment 2. FIG. It is a figure which shows the deviation | shift amount of the position of the pilot hole before and behind curvature generation | occurrence | production. It is a figure which shows the relationship between the deviation | shift amount of the position of the pilot hole before and behind curvature generation | occurrence | production, and curvature height.

Embodiment 1
With reference to FIG.1 and FIG.2, the manufacturing method of the laminated steel plate for motors which concerns on Embodiment 1 is demonstrated. FIG. 1 is a schematic view showing an apparatus for manufacturing a laminated steel sheet for motors. FIG. 2 is a schematic diagram showing one step of the method for manufacturing the laminated steel sheet for motors according to the first embodiment. The method for manufacturing a laminated steel sheet for motors according to Embodiment 1 includes a method for detecting warpage of the laminated steel sheet for motors.

(Production equipment for laminated steel sheets for motors)
In the method for manufacturing a laminated steel sheet for motors according to Embodiment 1, the manufacturing apparatus 10 for laminated steel sheets for motors shown in FIG. 1 can be used. An apparatus 10 for manufacturing a laminated steel sheet for motor includes an uncoiler 1, a leveler 2, a feeder 3, a punching unit 4, a work hardening unit 5, a measuring unit 6, a distortion removing unit 7, and a warp height feedback control. Part 8. The uncoiler 1, the leveler 2, the feeder 3, the punching unit 4, the work hardening unit 5, the measuring unit 6, and the distortion removing unit 7 may be arranged in this order in the advancing direction of the workpiece W <b> 1. .

  The uncoiler 1 includes a roller 11 around which the workpiece W1 can be wound, and can drive the workpiece W1 to the leveler 2 by driving the roller 11. The uncoiler 1 may include a drive source that drives the roller 11. The workpiece W1 is specifically a strip-shaped steel plate.

  The leveler 2 includes a plurality of rollers 21, and the plurality of rollers 21 are arranged in two rows along the traveling direction of the workpiece W1. The leveler 2 receives the workpiece W1 sent from the uncoiler 1. The plurality of rollers 21 apply a predetermined pressure to the work W1 by sandwiching the work W1. The plurality of rollers 21 are supported so as to be movable in a direction intersecting the workpiece W1, and the pressure applied to the workpiece W1 can be adjusted. The leveler 2 can receive a command signal from the warp height feedback control unit 8 and change the pressure applied to the workpiece W1 based on the received command signal.

  The feeder 3 may be any device that supplies the workpiece W1 at a predetermined supply speed. Specifically, the feeder 3 includes a roll 31 that sandwiches the workpiece W1 and a drive source (not shown) that rotationally drives the roll 31, and the drive source can adjust the drive speed of the roll 31.

  The punching unit 4 may be any device that punches out a portion corresponding to the laminated steel sheet for motor from the workpiece W1. Specifically, the punching unit 4 includes a punching press upper die (not shown), a punching press lower die (not shown), and a press machine (not shown) that movably supports the punching press upper die and the punching press lower die. Abbreviation). Here, the shape of the laminated steel plate for motor is, for example, a shape corresponding to at least a part of the stator or the rotor. The shape of the laminated steel sheet for a motor is preferably punched out so that the punched portion and the portion connected to the workpiece W1 remain. In the next step, this punched portion is connected to the workpiece W1, which is preferable because workability is improved.

  The work hardening unit 5 may be an apparatus that work hardens the workpiece W1. Specifically, the upper press mold (not shown), the lower press mold (not shown), and the upper press mold and the lower press mold are moved. A press machine (not shown) that supports the machine. The work hardening unit 5 can be work hardened by plastic working a portion of the laminated steel plate for motor punched out.

  As shown in FIG. 2, the measurement unit 6 includes cameras 61 and 62 and a warp height detection unit 63. The camera 61 shoots from the side of the workpiece W1, and the camera 62 shoots from below the workpiece W1. After the measurement unit 6 receives the work W1 work hardened by the work hardening unit 5, the cameras 61 and 62 pick up the work W1, and the warp height detection unit 63 uses the work W1 based on the picked up image. Detect the amount of warpage. The warp height detection unit 63 transmits a warp information signal including the measured warp magnitude to the warp height feedback control unit 8.

  The strain removing unit 7 may be any device that removes strain. Specifically, the upper press die (not shown), the lower press die (not shown), and the upper press die and the lower press die are movably supported. Press machine (not shown). The distortion removing unit 7 removes distortion by sandwiching and pressing the work W1 between the upper press mold and the lower press mold.

  The warp height feedback control unit 8 receives the warp information signal from the measurement unit 6, and based on the warp information, if the warp magnitude of the workpiece W1 is larger than a predetermined value, the warp height feedback control unit 8 When the command signal is transmitted and the magnitude of the warp is not more than a predetermined value, the command signal is not transmitted to the leveler 2 and the distortion removing unit 7. Such a command signal indicates information for adjusting the pressure applied from the leveler 2 to the workpiece W1, the die heights of the upper press die and the lower press die included in the distortion removing unit 7, and the working pressure thereof.

  The warp height detection unit 63 and the warp height feedback control unit 8 include, for example, a sequence control device, a programmable logic controller (PLC), an arithmetic circuit having a CPU (Central Processing Unit), and a program memory as hardware configurations. A storage device having a random access memory (RAM), a read only memory (ROM), or the like may be provided.

(Manufacturing method of laminated steel sheet for motor)
First, the workpiece W1 is sent from the uncoiler 1 to the leveler 2. The workpiece W1 is pressed by the leveler 2 to remove distortion (leveler step ST1). Here, the removed distortion is caused by winding the workpiece W1 around the uncoiler 1. The pressure on the workpiece W1 by the leveler 2 may be changed according to a command signal from the warp height feedback control unit 8.

  Subsequently, the workpiece W1 is sent from the leveler 2 to the punching unit 4 via the feeder 3, and a portion corresponding to the laminated steel sheet for a motor is punched from the workpiece W1 (punching step ST2).

  Subsequently, the workpiece W1 is sent from the punching unit 4 to the work hardening unit 5, and a portion corresponding to the laminated steel sheet for a motor is pressed and work hardened (work hardening step ST3). Note that at least one of the punching process ST2 and the work hardening process ST3 may be referred to as a pressing process.

  Subsequently, the workpiece W1 is sent from the work hardening unit 5 to the measurement unit 6, and the warpage amount of the workpiece W1 is measured (warpage amount measurement step ST4). Specifically, the camera 61 images the workpiece W1 from the side of the workpiece W1. The camera 62 images the workpiece W1 from below the workpiece W1.

  The workpiece W1 has a plurality of pilot holes W1a (may be referred to as position confirmation holes) for confirming the position of each part. The pilot holes W1a are arranged in two rows in the longitudinal direction of the workpiece W1 with a predetermined interval. Of the two rows, one row is arranged on one end side of the workpiece W1, and the other row is arranged on the other end side of the workpiece W1.

  The feed level L1 and the warped portion W1c of the workpiece W1 are specified from the image captured by the camera 61 and the image captured by the camera 62. The feed level L1 is the height of a portion corresponding to the warped portion W1c of the workpiece W1 when the feed level L1 is fed from the feeder 3 to the punching unit 4. The warp height detection unit 63 measures the distance from the feed level L1 to the warp portion W1c of the workpiece W1, and detects the warp height H1. The warp height detection unit 63 transmits a warp information signal including the detected warp height H <b> 1 to the warp height feedback control unit 8. The warp height feedback control unit 8 transmits a command signal to the leveler 2 and the distortion removing unit 7 in accordance with the warp height H1. Specifically, when the warp height H1 is higher than a predetermined value, the warp height feedback control unit 8 transmits a command signal to the leveler 2 and the distortion removing unit 7. The predetermined value determined in advance is, for example, the maximum value of the allowable range of warpage of the finally formed laminated steel sheet for motors.

Finally, the workpiece W1 is sent out from the measurement unit 6 to the distortion removing unit 7, and the distortion of the workpiece W1 is removed (distortion removing step ST5). The processing pressure applied to the workpiece W1 by the strain removing unit 7 and the die heights of the upper press die and the lower press die included in the strain removing unit 7 are adjusted according to a command signal from the warp height feedback control unit 8.
In addition, the laminated steel sheet for motors can be obtained by removing the part corresponding to the laminated steel sheet for motors from the workpiece W1 from which the distortion is removed, and laminating the removed part. Moreover, after laminating | stacking the obtained laminated steel plate for motors, you may fix a magnet to a laminated steel plate using resin.

  As mentioned above, according to the manufacturing method of the laminated steel plate for motors according to the first embodiment, the warp height H1 can be detected according to the part of the workpiece W1 because the warp height is detected after the work hardening. Moreover, since the processing conditions in the processes before and after the detection are changed based on the detected warp height H1, the warp height H1 can be suppressed according to the part of the steel sheet. Moreover, the laminated steel plate for motors which suppressed curvature height H1 can be manufactured, and the motor containing this manufactured laminated steel plate for motors has a favorable space factor.

Embodiment 2
With reference to FIGS. 3-5, the manufacturing method of the laminated steel plate for motors which concerns on Embodiment 2 is demonstrated. FIG. 3 is a schematic diagram showing one step in the method of manufacturing a laminated steel sheet for motors according to the second embodiment. FIG. 4 is a diagram illustrating a deviation amount of the position of the pilot hole before and after the occurrence of warping. FIG. 5 is a diagram showing the relationship between the amount of deviation of the position of the pilot hole before and after the occurrence of warpage and the warp height. The manufacturing method of the laminated steel sheet for motors according to Embodiment 2 has the same configuration as the manufacturing method of the laminated steel sheet for motors according to Embodiment 1 except for warpage amount measurement step ST4. A description of the same configuration is omitted, and a different configuration is described.

  First, similarly to the manufacturing method of the laminated steel sheet for motors according to the first embodiment described above, the leveler process ST1 to the work hardening process ST3 are performed.

  Subsequently, the workpiece W1 is sent from the work hardening unit 5 to the measurement unit 6, and the warpage amount of the workpiece W1 is measured (warpage amount measurement step ST24).

  Specifically, as shown in FIG. 3, the camera 62 images the workpiece W1 from below the workpiece W1. The workpiece W1 has a plurality of pilot holes W1a (may be referred to as position confirmation holes) for confirming the position of each part. The pilot holes W1a are arranged in two rows in the longitudinal direction of the workpiece W1 with a predetermined interval. Of the two rows, one row is arranged on one end side of the workpiece W1, and the other row is arranged on the other end side of the workpiece W1.

As shown in FIG. 4, the distance P1 between the pilot holes W0a of the reference workpiece W0 and the amount of displacement Z1 between the pilot holes W1a and the pilot holes W0a in the image captured by the camera 62 are obtained. The reference workpiece W0 is the workpiece W1 before the warp occurs, for example, the workpiece W1 before the punching process ST2. The image information of the reference workpiece W0 is obtained by imaging the workpiece W1 before starting the manufacturing method. Further, the image information of the reference workpiece W0 may be stored in the storage unit of the warp height detection unit 63. Specifically, the distance P1 between the pilot holes W0a of the reference workpiece W0 is the distance between the center points of the pilot holes W0a. Further, the amount of deviation Z1 between the pilot hole W1a and the pilot hole W0a in the image captured by the camera 62 is the distance between the center point of the pilot hole W1a and the center point of the pilot hole W0a.
The distance P1 between the pilot holes W0a corresponds to a pitch when the workpiece W1 is fed, and is also referred to as a feed pitch P1. As shown in FIG. 5, the warp height detection unit 63 obtains the warp angle θ using the following equation 1, and then obtains the warp height H <b> 1 using equation 2.
cos θ = P1 / (P1-Z1) (... Equation 1)
H1 = P1 × sin θ (Equation 2)
The warp height detection unit 63 transmits a warp information signal including the obtained warp height H1 to the warp height feedback control unit 8, and the warp height feedback control unit 8 outputs a command signal according to the warp height H1. 2 and the distortion removing unit 7. Specifically, when the warp height H1 is higher than a predetermined value, the warp height feedback control unit 8 transmits a command signal to the leveler 2 and the distortion removing unit 7. The predetermined value determined in advance is, for example, the maximum value of the allowable range of warpage of the finally formed laminated steel sheet for motors.
Here, the value of the distance P1 may be obtained based on the image information of the reference workpiece W0. Further, since the value of the distance P1 is a feed pitch and is a fixed value that is arbitrarily set, for example, it may be obtained using a preset fixed value. Therefore, in order to obtain the value of the distance P1, the image information of the reference workpiece W0 is not necessarily required.

  Finally, the distortion removing step ST5 is performed in the same manner as in the method for manufacturing the laminated steel sheet for motors according to the first embodiment described above.

  As described above, according to the method for manufacturing a laminated steel sheet for motors according to the second embodiment, the warp height H1 is detected after work hardening, as in the method for producing the laminated steel sheets for motor according to the first embodiment. Therefore, the warp height H1 can be accurately detected. Moreover, since the processing conditions in the processes before and after the detection are changed based on the detected warp height H1, the warp height H1 can be suppressed according to the part of the steel sheet. Moreover, the laminated steel plate for motors which suppressed curvature height H1 can be manufactured, and the motor containing this manufactured laminated steel plate for motors has a favorable space factor.

  Moreover, according to the manufacturing method of the laminated steel sheet for motors according to the second embodiment, the magnitude of warpage can be obtained based on the amount of deviation of the pilot holes. Therefore, it is possible to determine the magnitude of the warp only by measuring the amount of deviation. Furthermore, since the limited range is measured compared with the manufacturing method of the laminated steel sheet for motors according to the first embodiment, the magnitude of warpage can be detected with high accuracy. Furthermore, the curvature of a steel plate can be suppressed according to a site | part by changing the processing conditions of a steel plate according to the magnitude | size of the curvature detected accurately.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. For example, in the method for manufacturing a laminated steel sheet for motors according to the first and second embodiments, the image is taken from below the work W1, but the image may be taken from above the work W1. Moreover, in the manufacturing method of the laminated steel sheet for motors according to the first and second embodiments, the warp height is obtained from an image obtained by imaging the workpiece W1, but the workpiece W1 is irradiated with the laser, and the phase difference between the irradiation laser and the reflected laser is calculated. The height of warpage may be obtained by measuring. Further, the warp height may be obtained by performing an electrical measurement in which the change in the magnetic field due to the warp of the workpiece W1 is replaced with a current. Moreover, in the manufacturing method of the laminated steel sheet for motors according to the second embodiment, the position of the pilot hole W1a is measured, but the portion punched in the punching process step ST2 may be measured.

ST2 Machining process ST3 Work hardening process ST24 Warpage amount measuring process W1 Work W1a Pilot hole W0 Standard work W0a Pilot hole Z1 Deviation amount

Claims (1)

A method for detecting warpage caused by press working of laminated steel sheets for motors,
A steel plate having position confirmation holes arranged at predetermined intervals is pressed,
Take an image of the pressed steel sheet,
Based on the amount of deviation between the position confirmation hole position in the captured image and the position confirmation hole position before press working, the warpage of the pressed steel sheet is obtained.

Images