JPS6118332B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for manufacturing a laminated core for electrical equipment.

As a laminated core manufacturing device, a progressive die is used to draw out the laminated core pieces into the die for outline cutting, and the previously drawn laminated core pieces in the die are caulked and joined together. There is something to do.

The laminated core manufactured by this device has a cut-and-raised protrusion on the laminated core piece that is later drawn into the hole that is the cut-and-raised protrusion mark of the laminated core piece that has been punched out and placed in the die. The protrusions are press-fitted and caulked to join them together. In addition, although the above laminated core pieces are cut and raised every predetermined number of pieces, and although there are no protrusions, there are holes where the cut and raised protrusions remain. The laminated core piece that is pulled into the die and the subsequent pieces that are pulled out following the laminated core piece become uncoupled due to the presence of the laminated core piece. That is, the laminated core pieces without cut and raised protrusions are placed at the lowest position, and the laminated core pieces that are pulled out until the next laminated core piece without cut and raised protrusions are combined together. It becomes one product laminated core.

Conventionally, the thickness of one product laminated core that is sequentially manufactured in a mold in this way was determined by the number of laminated core pieces. In other words, there are no cut-and-raised protrusions that would break the continuous connection by caulking, but there are punched-out holes in the cut-and-raised protrusions.A core piece with a so-called through hole is pulled out from a single product laminated core. For example, if the number of iron core plates to be configured is 50, a punch that punches a through hole every 50th plate is activated by a signal from the press counter and punches the through hole.

However, in general, JIS standards allow a tolerance of +10% for the thickness of electromagnetic steel sheets, which are the material for electrical equipment core plates.For example, if an electromagnetic steel sheet with a thickness of +10% is used. Calculating the case, if one product laminated core has 100 sheets and the plate thickness is 0.5 mm, the product laminated core will be 5 mm thicker than the specified thickness, and 10 magnetic steel sheets will be lost. It turns out. On the other hand, if electromagnetic steel sheets with negative tolerances are used, products that do not reach the specified thickness, i.e., have inferior electrical properties, will be manufactured, and the quality will not be stable in proportion to the variation in the thickness of the electromagnetic steel sheets. It turns out.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a laminated core manufacturing apparatus that can manufacture a product laminated core with a desired thickness regardless of variations in the thickness of electromagnetic steel sheets.

In order to achieve the above object, the present invention sequentially performs the required punching from a strip that is fed intermittently at a predetermined pitch, and also caulks the strip at a predetermined position in a portion that will become a laminated core piece by an amount that protrudes within the thickness of the strip. At the same time, forming protrusions and cutting the outer shape of the laminated core piece from the strip, the cut-out laminated core piece is laminated and fixed to the preceding laminated core piece by the caulking protrusion, and the caulking protrusion is removed at a predetermined time. In a laminated core manufacturing apparatus that determines the thickness of a product laminated core by punching out a product laminated core, a punch for forming the caulking protrusion is moved to a punch holder to form the caulking protrusion.
and the second position where the caulking protrusion is removed.
a thickness detecting means for detecting the plate thickness each time the strip is fed intermittently; an adding means for sequentially adding the detected thickness; and a thickness detecting means for setting the thickness of the product laminated core. a setting means; controlling the positioning means so that the punch is in a first position until the added value reaches the thickness setting value; and when the added value reaches the thickness setting value, the punch is in the second position; A control means is provided for controlling the positioning means so as to reach the position , and for resetting the added value.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention as a progressive die used as a lamination die. This mold device is for manufacturing a laminated iron core for a rotor of a motor from a strip 1, and the first to fifth stations, . . .
, has. At the first station 1, the second
As shown in the figure, a skew escape round hole 2 and a pilot hole 3 are bored. A shaft hole 4 and a slot 5 are bored in the second station. At the third station, a cut-and-raised projection hole 6 and a cut-and-raised projection 7 (see FIGS. 3a and 3b) communicating with the skew escape round hole 2 are formed. Furthermore, in this third station, as shown in FIGS.
Holes 6a corresponding to cut-and-raised protrusions are formed at predetermined thickness intervals. Due to the structure of the mold, the fourth station is an idle station to maintain strength, and processing is not performed at the fifth station.
Inside the die 8, the outer shape of the laminated core piece 9, which will become the rotor lamination, is cut out, caulked, and skewed.

The punch 24 at the third station
As schematically shown in the figure, the lower end cutting edge 24a is formed in the shape necessary for forming the cut and raised protrusion 7, and the upper end serving as the base is formed into a cam portion 26 facing into the punch holder 25. This cam portion 26 is a tapered cam and is always in contact with a cam 27 that is driven forward and backward by a solenoid 18 attached to the punch holder 25. When the reciprocating punch holder 25 descends to the lowest position, the punch 2
The amount by which the cutting edge 24a of the stripper 28 protrudes from the lower surface of the stripper 28 that presses the strip 1 is determined by the amount that the cutting protrusion 7 has when forming the cut protrusion 7 and the cut protrusion hole 6. This is the amount that can be maintained at a protrusion amount that does not exceed 2.
The amount of protrusion is more than double (see Figures 6 and 7).
This change in the amount of protrusion is applied to the punch 24 by displacement of the cam 27. The time to increase the amount of punch protrusion is when the thickness of the laminated cores laminated and caulked at the fifth station reaches the thickness required for one product laminated core.

In the present invention, lamination is performed at the fifth station,
In order to detect the thickness of the laminated iron core to be caulked, the maximum plate thickness of the strip 1 fed in every stroke of the mold device 30 is detected every stroke,
This is done by accumulating this.

Thickness detectors 31 are disposed at appropriate locations on the strip 1 fed into the mold device 30. As shown in FIG.

The thickness detector 31 continuously detects the thickness of the strip 1 and outputs a voltage signal corresponding to this thickness. For example, a metal piece (not shown) of a predetermined area is arranged parallel to the strip 1, One that utilizes changes in the capacitance value of the capacitor formed by this metal piece and strip 1, or one that uses strip 1
A known method may be used, such as a method in which a coil is disposed close to the strip 1 and changes in the inductance of the coil due to eddy currents generated in the strip 1 are utilized.

The output signal of thickness detector 31 is processed by an electrical circuit shown in block diagram form in FIG.

The output signal of the thickness detector 31 is applied to a peak level measuring device 32.

The peak level measuring device 32 includes a circuit that temporarily stores only the maximum level signal from the sequentially changing output of the thickness detector 31, and applies this maximum level signal to the analog-to-digital converter 33.

The analog-to-digital converter 33 is opened for a certain period of time near the end of one press stroke by a signal S1 (an example is shown in FIG. 9a) from the press device 34 that pressurizes the mold device 30, and the peak level measuring device The temporarily stored signal is sent to one of the press devices 34.
Pulse signal S2 generated at each end of stroke
It is reset by (FIG. 9b).

Therefore, the analog-to-digital converter 33 outputs a number of pulses proportional to the maximum thickness of each core piece to be laminated while the pulse signal S1 for each stroke of the press device 34 is at a high level.
For example, if the analog-digital converter 33 is 1/100mm
If the thickness of the strip 1 corresponding to the first stroke of the press device 34 is 0.04 mm, the pulse signal S1 from the analog-to-digital converter 33 is generated while the pulse signal S1 is at a high level. Four pulses are output to P ₁ (Fig. 9c)
Similarly, each stroke generates a number of pulses proportional to the thickness of the corresponding strip.

The output pulses of the analog-to-digital converter 33 are sequentially added by an adder 35, and the thickness of the laminated cores sequentially laminated at the fifth station (FIG. 1) is counted. (See Figure 9) On the other hand, the thickness of the product laminated core is determined by the product thickness setting device 3.
6 is preset as a digital value.

The count value of the adder 35 is compared with the set value of the product thickness setting device 36 by a comparator 37.

The comparator 37 is configured to output a signal when the output of the adder 35, which increases sequentially for each stroke of the press device 34, matches the set value of the setter 36.

Therefore, when the count value of the adder reaches the set value of the setter 36, a signal is output, and this signal is applied to the solenoid 18 (see FIG. 5) that drives the punch 24 in the third station, so that the punch 24 is ejected. The protrusion hole 6 is made into a through hole 6a (see FIGS. 3 and 4) to prevent the punched core pieces at the fifth station from joining together any further and to control the thickness of one product. At the same time, adder 3
The count value of 5 is reset and counting for the next product is started.

Note that the die 8 at the fifth station for laminating and caulking is provided with a pedestal 29 that presses into contact with the laminated core piece 9 from below. This cradle is a tilting pedestal 1 mounted on a support pedestal 12 provided at the upper end of the rod 11 of the air cylinder 10.
3, it is rotatably attached via a thrust bearing 14. The laminated core piece 9 placed on the pedestal 29 and caulked in sequence under the pressure of the punch 15 and the pedestal 29 becomes one product laminated core, and by further pulling out the laminated core piece 9, the product is laminated. If the air cylinder 10 is switched and operated when the core is lowered and the outer peripheral edge of the product laminated core no longer contacts the inner peripheral surface 8a of the die, the rod 11 is lowered at that time. The tilting table 13 comes into contact with the protrusion 16 and is prevented from passing, so that the tilting table 13 tilts about the shaft 17 as a fulcrum, and the product laminated core on the cradle 29 is transferred onto the chute 38. It is taken out by sliding down. In this embodiment, the thrust bearing 14 is provided between the pedestal 29 and the tiltable pedestal 13 so that the pedestal 29 can rotate horizontally. This is because the skew amount applied to the laminated core is provided by forced rotation of the die 8 at an angle equivalent to the skew amount. Therefore, unnecessary resistance will not occur during the above rotation.

Further, in the above embodiment, a thickness detector 31 is disposed in front of the molding device 30 to detect the thickness of the strip 1 before being fed into the molding device 30, and the thickness of the laminated core is controlled based on this detected value. Because of this, there is a gap between the thickness detector 31 and the punching part (fifth station), and errors due to this gap are a problem, but generally the thickness of the plate material changes smoothly, so there is a large error. It never happens.

As explained above, since the present invention has the above structure, regardless of the variation in the thickness of the strip 1, the variation in the thickness of the product laminated core is kept within the thickness of one strip. The excellent effect of being able to efficiently produce product laminated iron cores with uniform thickness is obtained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing an embodiment of the laminated core manufacturing apparatus of the present invention, FIG. 2 is a plan view of a strip, and FIGS. - Longitudinal cross-sectional view taken from arrow A, Figures 4 a and b are enlarged plane views showing the state in which holes are drilled in the cut-and-raised protrusion portion, and longitudinal cross-sectional views taken from the B--B arrow, and Figure 5 is for the formation of cut-and-raised protrusions. A schematic vertical cross-sectional view of the punch mechanism, FIG. 6 is an enlarged vertical cross-sectional view of a state in which a cut and raised protrusion is formed, FIG. 7 is an enlarged cross-sectional view of a state in which a hole is drilled in a portion corresponding to the cut and raised protrusion, and FIG. 8 is the same implementation. FIG. 9 is a block diagram showing the control of the thickness of the laminated core in this example, and FIG. 9 is a timing chart showing an example of the signals of each part in the block diagram of FIG. 31...Thickness detector, 32...Peak level measuring device, 33...Analog-digital converter, 34...
...Press device, 35...Adder, 36...Product thickness setting device, 37...Comparator, 18...Punch drive solenoid.

Claims (1)

[Scope of Claims] 1. The required punching is performed sequentially from the strip that is fed intermittently at a predetermined pitch, and caulking protrusions are formed at predetermined positions on the portions that will become the laminated core pieces with a protrusion within the thickness of the strip. , At the same time as cutting out the outer shape of the laminated core piece from the strip, the cut out outer shape of the laminated core piece is laminated and fixed to the preceding laminated core piece by its caulking protrusion, and the caulking protrusion is removed at a predetermined time. In a laminated core manufacturing apparatus that determines the thickness of a product laminated core by a positioning means for positioning the strip at a second position; a thickness detecting means for detecting the plate thickness each time the strip is fed intermittently; an adding means for sequentially adding the detected thicknesses; and a thickness detecting means for setting the thickness of the product laminated core. a setting means; controlling the positioning means so that the punch is in a first position until the added value reaches the thickness setting value; and when the added value reaches the thickness setting value, the punch is in the second position; A laminated iron core manufacturing apparatus comprising: a control means for controlling the positioning means so as to be at the position and resetting the added value.