JPH11186062A - Low-noise laminated core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a laminate core with an superior iron-loss characteristic and make its noise low when using it, by setting caulked pressure by rivets at a specific value or more. SOLUTION: A plurality of non-oriented silicon steel plates punched in a predetermined shape are stacked, and the caulking pressure when fastening them to each other by rivets is made to be 50 kg/cm<2> . Also, the punches shape of the plurality of stacked non-oriented silicon steel plates is made U-shaped. Furthermore, the saturated magnetostrictive value thereof is made not larger than 1.1×10<-6> . As a result, a low-noise laminated core with an excellent iron-loss characteristic can be obtained. For example, punching in an FEI 40 size non- oriented silicon steel plats having each plate thickness of 0.35 mm and containing substantially 3 wt.% Si, a laminated EI type core 1 is caulked under a pressures of 50 and 60 kg/cm<2> through rives 2 to thereby make its noise reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-noise laminated iron core suitable for transformers and reactors.

[0002]

2. Description of the Related Art Conventionally, wound iron cores or laminated iron cores of silicon steel sheets have been used as iron cores for transformers and reactors. A wound iron core of a silicon steel sheet is an iron core formed by winding a single silicon steel sheet into a plurality of layers, and since it is used by being excited in the winding direction, a directional silicon steel sheet that is advantageous in terms of iron loss characteristics is generally used. I have.

On the other hand, a laminated iron core of a silicon steel sheet is an iron core obtained by laminating a plurality of silicon steel sheets punched into an EI type or an EE type or another desired shape, and a non-oriented silicon steel sheet is exclusively used. . The reason is that, in the case of a grain oriented silicon steel sheet, it is disadvantageous because it is excited not only in the longitudinal direction of the silicon steel sheet coil but also in the C direction where iron loss is significantly deteriorated.

[0004]

As means for fixing a plurality of laminated silicon steel sheets in a laminated iron core made of a non-oriented silicon steel sheet, a method of containing a resin, a method of welding, a method of caulking and fixing with a rivet, There are methods such as bolting.

According to the method of caulking and fixing a plurality of laminated silicon steel sheets with rivets, the manufacturing process can be simplified, the manufacturing operation can be automated, and the manufacturing cost can be reduced. However, in the case of the iron core in which the laminated silicon steel plates are caulked and fixed with rivets, there is a problem that the iron core vibrates violently at the time of use and the noise is remarkably increased.

Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a low-noise laminated iron core having excellent iron loss characteristics and low noise during use, which is suitable for transformers and reactors. It is in.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems and to develop a low-noise laminated core having excellent iron loss characteristics and low noise. As a result, when caulking pressure at the time of caulking and fixing a plurality of laminated iron cores with rivets is limited to a specific range,
It has been found that the noise of the iron core during use can be reduced.

[0008] The present invention has been made based on the above findings, and is a laminated iron core formed by laminating a plurality of non-oriented silicon steel sheets punched into a predetermined shape, caulking with rivets and fixing. Wherein the caulking pressure of the rivet is set to 50 kg / cm ² or more.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a caulking pressure for laminating a plurality of non-oriented silicon steel sheets punched into a predetermined shape and fixing them with rivets should be 50 kg / cm ² or more. By setting the caulking pressure to 50 kg / cm ² or more, the laminated plurality of non-oriented silicon steel sheets are tightened,
As a result, the vibration of the iron core during use is suppressed, and noise can be reduced. When the caulking pressure is less than 50 kg / cm ² , the effect of suppressing vibration is small.

Further, if the punched shape of the laminated non-oriented silicon steel sheets is U-shaped, the effect of reducing the noise of the iron core can be further enhanced, and the saturation magnetostriction value of the laminated non-oriented silicon steel sheets can be further improved. Is set to 1.1 × 10 ⁻⁶ or less, the laminated core has low magnetostriction and excellent performance in iron loss characteristics, and the noise reduction effect can be further enhanced.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. [Example 1] A sheet thickness of 0.35 mm and substantially 3 wt.
Five sets of EI-type laminated cores were prepared by punching out and laminating a non-oriented silicon steel sheet containing i to the FEI 40 size described in JIS C 2514. As shown in FIG. 5, five sets of EI type laminated iron cores 1 were caulked by rivets ² with five kinds of caulking pressures of 20 to 60 kg / cm ² and fixed.

The noise when the laminated iron core thus prepared was excited at a frequency of 400 Hz and a magnetic flux density of 1.0 T was measured. The noise was measured with a sound level meter (A scale) at a position 10 cm from the center of the side of the iron core.
Was performed. The measurement results are shown in Table 1 and FIG.

[0013]

[Table 1]

As can be seen from Table 1 and FIG. 1, the rivet setting pressure is as low as 20 kg / c outside the scope of the present invention.
m ^2, the noise value of the comparison example 30 Kg / cm ² and 40 Kg / cm ² is
70 dB, 69 dB and 66 dB, while the rivet swaging pressure of 50 kg / cm ² and 60 kg / cm ² of the present invention were 59 dB and 58 dB, respectively.
The noise was significantly reduced as compared with the comparative example. [Embodiment 2] The thickness of S is substantially 3 wt.
A non-oriented silicon steel sheet containing i was punched out and laminated in a U-shape so as to have the same size as the CS50 size described in the standards of the Japan Winding Iron and Steel Industry Association.
Five sets of letter-shaped laminated cores 3 were prepared. Then, as shown in FIG. 7, five sets of U-shaped laminated cores 3 are
It caulked and fixed by five kinds of caulking pressures of 0 to 60 kg / cm ² .

Noise was measured when the laminated iron core thus prepared was excited at a frequency of 400 Hz and a magnetic flux density of 0.5 T. As described above, the noise was measured by a sound level meter (A scale) at a position 10 cm from the center of the side surface of the iron core. The measurement results are shown in Table 2 and FIG.

[0016]

[Table 2]

As is apparent from Table 2 and FIG. 2, the rivet setting pressure is lower than 20 kg / c outside the scope of the present invention.
m ^2, the noise value of the comparison example 30 Kg / cm ² and 40 Kg / cm ² is
The noise values of the present invention with the rivet caulking pressure of 50 kg / cm ² and 60 kg / cm ² were 63 dB and 59 dB, while the noise values were 75 dB, 77 dB and 74 dB.
By making the shape of the laminated core U-shaped, noise could be further reduced. Example 3 A high silicon steel sheet having a thickness of 0.2 mm, substantially containing 5.9 wt.% Si, and having a DC saturation magnetostriction of 1.1 × 10 ⁻⁶ was manufactured by Nippon Rolling Iron Industrial Co., Ltd. CS5 described in the association standard
Five sets of U-shaped laminated cores 3 shown in FIG. 6 were punched and laminated in a U-shape so as to have the same size as the 0 size. Then, as shown in FIG. 7, five sets of U-shaped laminated cores 3 were caulked with rivets 2 by five kinds of caulking pressures of 20 to 60 kg / cm ² and fixed.

The noise generated when the laminated core thus prepared was excited at a frequency of 400 Hz and a magnetic flux density of 0.5 T was measured by the method described above. The measurement results are shown in Table 3 and FIG.

[0019]

[Table 3]

As is apparent from Table 3 and FIG. 3, the rivet setting pressure is 20 kg / c which is low outside the range of the present invention.
m ^2, the noise value of the comparison example 30 Kg / cm ² and 40 Kg / cm ² is
In contrast to 66 dB, 64 dB and 61 dB, the noise values of the present invention in which the rivet swaging pressure was 50 kg / cm ² and 60 kg / cm ² were 45 dB and 43 dB, respectively.
The punching shape is U-shaped, and the saturation strain rate is 1.1 × 10
^In the case of a high silicon steel sheet of ^-6 or less, the noise could be further reduced significantly. Example 4 A high silicon steel sheet having a thickness of 0.1 mm and containing substantially 6.5 wt.% Of Si and having a saturation magnetostriction of 0.08 × 10 ⁻⁶ was prepared as shown in FIG. Punched into a U-shape and laminated, five sets of U-shaped laminated cores 3 shown in FIG. 7 were prepared.
Then, as shown in FIG. 7, five sets of U-shaped laminated cores 3 are provided.
Was caulked with rivets 2 by five kinds of caulking pressures of 20 to 60 kg / cm ² and fixed.

The noise generated when the laminated core thus prepared was excited at a frequency of 1000 Hz and a magnetic flux density of 0.5 T was measured by the method described above. The measurement results are shown in Table 4 and FIG.

[0022]

[Table 4]

As is clear from Table 4 and FIG. 4, the rivet setting pressure is lower than 20 kg / c outside the scope of the present invention.
m ^2, the noise value of the comparison example 30 Kg / cm ² and 40 Kg / cm ² is
The noise values of the present invention with the rivet caulking pressure of 50 kg / cm ² and 60 kg / cm ² were 63 dB and 59 dB, while the noise values were 75 dB, 77 dB and 74 dB.
When a high silicon steel sheet having a U-shaped punching shape and a small saturation magnetostriction value was used, the noise could be further remarkably reduced.

[0024]

As described above, according to the present invention,
An industrially useful effect of obtaining a low-noise laminated core having excellent magnetic properties and having excellent iron loss characteristics, low noise, excellent mass productivity, and low cost can be produced.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between caulking pressure and noise when a non-oriented silicon steel sheet is punched and laminated and fixed with rivets to form a laminated iron core.

FIG. 2 is a graph showing the relationship between caulking pressure and noise when a U-shaped laminated core is punched and laminated and fixed with rivets to form a laminated core.

FIG. 3 is a graph showing the relationship between caulking pressure and noise when a high silicon steel sheet having a saturation magnetostriction of 1.1 × 10 ⁻⁶ is punched and laminated in a U-shape and fixed by rivets to form a laminated iron core. It is.

FIG. 4 is a graph showing the relationship between caulking pressure and noise when a high silicon steel sheet is punched and laminated in a U-shape and fixed by rivets to form a laminated iron core.

FIG. 5 is a plan view showing an EI type laminated iron core.

FIG. 6 is a plan view showing a U-shaped laminated core.

FIG. 7 is a perspective view showing a U-shaped laminated core.

[Explanation of symbols]

 1 EI type laminated core 2 Rivet 3 U-shaped laminated core

Claims (3)

[Claims] 1. A laminated iron core formed by laminating a plurality of non-oriented silicon steel sheets punched into a predetermined shape and caulking with a rivet, and fixing the rivet with a caulking pressure of 50 kg / cm ² or more. A low-noise laminated iron core characterized by: 2. The low-noise laminated core according to claim 1, wherein a punched shape of the non-oriented silicon steel sheets to be laminated is U-shaped. 3. The low-noise laminated core according to claim 1, wherein the non-oriented silicon steel sheet to be laminated has a saturation magnetostriction value of 1.1 × 10 ⁻⁶ or less.