JPH0376101B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a technology for manufacturing a laminated core, and more particularly to a method for manufacturing a laminated core using a progressive die device configured to perform lamination and caulking simultaneously during the core outer diameter punching process.

Conventionally, there is a method as described in Japanese Patent Publication No. 55-11940 to manufacture laminated cores using this type of progressive die equipment, and in order to prevent the thickness deviation of the core material during rolling from affecting the product thickness. A method such as that disclosed in Japanese Patent Application Laid-Open No. 129557/1983 has been proposed.

However, such conventional methods have the disadvantage of complicating the structure and control and increasing the size of the equipment.Furthermore, in order to eliminate thickness deviation, the punch is rotated by the rotation of the press crankshaft every time a predetermined number of sheets are punched. The blanking die starts rotating at a predetermined angle (180°) within a short time (for example, 0.05 seconds) within half a cycle when it is away from the iron core thin plate.
The rotation of the blanking die must be completed accurately and stopped, but in reality, the mold side cannot follow such high-speed movement, and in reality, the press side operation is stopped until the mold side, that is, the blanking die completes its operation. It has the problem that it cannot function unless it is otherwise used, and has the serious drawback that it conversely reduces the ability of the press. In addition, because the blanking die is directly rotated, it has the disadvantage that the finely adjusted clearance between the die and the punch may be affected and the blade may be struck, and there are concerns about safety.

The present invention was made based on the above situation, and relates to a new manufacturing method that provides a laminated core with a uniform product thickness even if the thickness deviation of the core material is eliminated. In this method of manufacturing a laminated core, in the core outer diameter punching and lamination caulking process, a predetermined number of core thin plates are separated and drawn into a die part, and the core is inserted into the die part and a ring located below it. When the thin plates are full, only a predetermined number of separated iron core thin plates located in the ring are rotated by a predetermined angle, and then a predetermined number of iron core thin plates separated and stacked in the die section are rotated. This method is characterized in that a product is obtained by tight bonding, and details will be explained below with reference to Examples.

FIG. 1 shows a cross-sectional view of a core outer diameter punching process portion in a progressive die device according to an embodiment of the present application. In this figure, the die part of the lower mold K is composed of a die 1 and a squeeze ring 2, and has an inner diameter 1a where thin iron core plates are pulled out and laminated by a punch P.
and an inner diameter 2a. squeeze ring 2
The inner diameter 2a is formed to be slightly smaller than the outer diameter of the product so that lateral pressure for caulking can be applied. The squeeze ring 2 has an inner diameter 3a slightly larger than the outer diameter of the product at the lower part of the squeeze ring 2.
A rotatable ring 3 is attached to the ring 3 via a bearing. A toothed portion 3b is formed on the outer periphery of this ring 3, and a cam index I is transferred to the side of the mold by a transmission means 4 such as a timing belt or chain.
It is connected to a driving means 5 such as a motor. A pressure pad 6 is constantly pressed against the lower surface 2b of the squeeze ring 2 by an operating means 7 such as a hydraulic cylinder installed on the press side. Also, limit switches 8 and 9 (1 in the figure) are located inside the squeeze ring 2.
(only one is shown) is attached, and its detection end is located on the lower surface 2b and is configured to transmit an output signal. In the figure, number 10 is an operating cylinder for discharging the core, 11 is a stopper, 12 is a thrust bearing, 1
3 indicates each pin.

Before explaining the operation of the above-mentioned constituent apparatus, the shape of the iron core thin plate formed in this mold apparatus up to the step of outer diameter punching will be explained. The laminated iron core manufactured by the apparatus according to the present invention is shown in Fig. 2~
It is composed of four types of core thin plates shown in FIG.
For example, if the product is made up of 14 core thin plates, every 7th core plate is drawn into the die part in a separated state, and the first core thin plate t1 to be punched out is caulked at three locations as shown in Figure 2. As shown in FIG. 3, the iron core thin plates t2, which are punched out from the second to the sixth sheets, have a punching hole a, and a caulking protrusion b is formed at the same position as the iron core thin plate t1, as shown in FIG. As shown in Fig. 4, the seventh core thin plate t3 punched out has a caulking protrusion c at the same position as the iron core thin plate t2, and is separated into three locations 180° rotated from the caulking protrusion c. A punch hole d is formed. Furthermore, the iron core thin plates t4 punched from the 8th to the 14th sheets have caulking protrusions e formed at the same positions as the separation holes d of the seventh sheet, as shown in FIG. Such iron core thin plates t1 to t4 are sequentially drawn into the die part and stacked.
Up to the 7th sheet is caulked, and the 8th to 14th sheets are similarly caulked, and the caulking positions of the 1st to 7th sheets and the 8th to 14th sheets are shifted by 180°. Further, the two are separated by a separation hole d.

Next, to explain the operation from Fig. 1, the iron core thin plates are pulled into the die 1 in this way, and then a certain number of iron core thin plates are pulled out into the die part (die 1 and squeeze ring 2) and into the ring 3. When inserted, the pressure pad 6 is slightly pushed down by the downward force of the punch P through the entire core thin plates laminated up to that point. At this time limit switch 8
is activated, and the hydraulic cylinder 7 descends to a certain position, that is, the position where the core thin plates (1st to 7th plates) on the pressure pad 6 are separated from the iron core thin plates (8th plate onwards) in the die section in the rotational direction, and then stops. Then, the driving means 5 rotates to rotate the ring 3 by a predetermined angle (for example, 180°) via the cam index I. Then, the pressure pad 6 connected by the pin 13 also rotates. Therefore, the first to seventh iron core thin plates on the pressure pad 6 are also rotated together, and the position of the caulking projection is also rotated by 180 degrees. In other words, by this rotational operation, the positions of the caulking protrusions for the entire product are aligned. And then hydraulic cylinder 7
rises again to within the detection range of the limit switch 9 (not shown). Furthermore, as the press crank rotates, the punch P descends and pulls out the thin iron core plate, and at the same time, the downward force of this punch P is applied to the entire thin iron core plate that has been pulled out between it and the presser pad 6.
The ~7th iron core thin plate and the 8th and subsequent iron core thin plates are caulked together. Furthermore, the pressure pad 6 is pushed down again by the downward force of the punch P. Then, the limit switch 9 (not shown) operates to lower the hydraulic cylinder 7 to the stopper 11. Therefore, the core for one product also descends (falls) at the same time, and the operating cylinder 10 discharges this core (product) to the side of the mold. Subsequently, this working cylinder 10 is retracted, and the hydraulic cylinder 7 is raised again to return to the initial state, and the above-described operation is repeated. In the above embodiments, it has been explained that the protrusion height of the caulking protrusion formed on the iron core thin plate is within the plate thickness range, but there are also protrusion shapes that have a height about twice the plate thickness, and in that case, In the separated portion, the same method can be achieved by forming the number of iron core thin plates corresponding to the protrusion height into a shape as shown in FIG. 4, for example. Further, the separated shape may be formed on the eighth sheet instead of the seventh sheet.

With the above configuration, there is no need to synchronize the required movement on the mold side with the high-speed movement on the press side.
Reliable operation can be performed without reducing press capacity,
Moreover, since the blanking die (die part) is not rotated, there is no fear of blade striking, which was a drawback of the conventional method, and it is possible to provide a method for manufacturing a laminated core that is highly safe and does not affect the thickness of the product due to thickness deviation of the core material. It is something.

[Brief explanation of drawings]

FIG. 1 is a front sectional view of the core outer diameter punching process part in the progressive mold device of the embodiment of the present application, and FIG.
5 to 5 respectively show plan views showing the shape of the iron core thin plate. (Explanation of symbols), 1...Die, 2...Squeeze ring, 3...Ring, 4...Transmission means, 5...
Drive means, 6... Pressure pad, 7... Operating means, 8, 9... Limit switch, 10... Operating cylinder, P... Punch, K... Lower mold, I...
Cam index.

Claims (1)

[Claims] 1. A method of manufacturing a laminated core using a progressive die device, in which the core outer diameter punching and lamination caulking steps shift the caulking position to a predetermined number of core thin plates, and the core thin plates with separation holes are formed. When the iron core thin plates are pulled into the die part and the die part and the ring located below the die part are full, only a predetermined number of separated iron core thin plates located in the ring are rotated to the caulking position. A method for manufacturing a laminated iron core, characterized in that the product is then caulked and joined with a predetermined number of iron core thin plates separated and laminated in a die part.