CN102975111A - Grinding method and special device for soft magnetic ferrite magnetic cores - Google Patents

Abstract

The invention discloses a grinding method of a soft ferrite core and special equipment thereof. The preparation method refers to arranging the magnetic cores in double or multiple rows longitudinally on a grinding machine, and using the same grinding machine to grind the arranged magnetic cores first. The method of plane machining followed by air gap machining. In the processing equipment, there are two or more equidistant cutting surfaces of the air-gap grinding wheel. The beneficial technical effects of the invention are high production efficiency, low processing cost, good product precision and consistency during grinding.

Description

A grinding method and special equipment for soft ferrite core

technical field

The invention relates to a deep processing method of magnetic components, in particular to a grinding method of a soft ferrite core and special equipment thereof.

Background technique

With the continuous development and improvement of the soft ferrite market, and with the continuous improvement of customer requirements, higher and higher requirements are put forward for soft ferrite materials and magnetic core components. For example, many power ferrite cores used in single-ended excitation circuits need to open an air gap. The main purpose is to reduce the remanence of the core when it works in an asymmetric magnetic field state. The larger the air gap, the smaller the remanence, so The magnetic core with the same volume can output more power, avoid magnetic saturation under large AC signal or DC bias, and can better control the inductance and improve the working stability of the transformer.

The grinding process is a key process in the deep processing of soft ferrite cores, especially for open cores, it is necessary to process planes or air gaps according to customer requirements for electrical performance. The cutting surface of the flat grinding wheel set on the upper end flattens or polishes the burr or concave-convex surface on the top surface of the side column of the magnetic core, so that the end faces of the two magnetic cores are fully contacted to maintain good inductance performance; On the machine tool, use the cutting surface of the air gap grinding wheel on the upper end of the machine tool to shorten the center column or side legs of the magnetic core. The depth of the center column or side legs in the magnetic core is set according to the size and accuracy of the magnetic core inductance. When designing the magnetic core inductance, customers pay more attention to the stability and consistency of the inductance of the magnetic core during use, because poor stability and consistency will cause fluctuations in the quality of the customer's own products, and the stability and consistency of air gap product processing have a great impact on Magnetic core devices have a greater impact. Due to the constraints of technology, equipment, grinding wheels, fixtures and other factors, the traditional plane and air-gap single-row processing method has always been used in the grinding process of magnetic cores, resulting in low production efficiency and poor product consistency. .

Contents of the invention

The technical problem to be solved by the invention is to solve the problems of low production efficiency, high processing cost, poor product precision and consistency when grinding soft ferrite cores.

The technical problem to be solved in the present invention is achieved through the following technical solutions: a grinding method for soft ferrite cores, the magnetic cores are arranged vertically in double or multiple rows on a grinding machine, and the aligned magnetic cores are aligned with the same grinding machine The method of performing flat machining first and then air gap machining.

Further: In the grinding method of the above soft ferrite core, the magnetic cores are arranged longitudinally in two or more rows along the direction of parallel double guide rails, and the height of the guide rails is designed according to the size of the processed magnetic core.

The present invention also provides special equipment for the grinding method of the above-mentioned soft ferrite core, which includes a grinding machine, a grinding machine assembly shaft is arranged at the upper end of the grinding machine, and a plane grinding wheel and an air gap grinding wheel controlled by a logic controller PLC are assembled on the grinding machine assembly shaft; The plane grinding wheel is provided with a plane grinding wheel base and a plane grinding wheel cutting surface at the front end of the plane grinding wheel base; the air-gap grinding wheel is provided with an air-gap grinding wheel base and an air-gap grinding wheel cutting surface at the front end of the air-gap grinding wheel base, There are two or more equidistant cutting surfaces of the air-gap grinding wheel.

Further: in the above-mentioned special equipment for the grinding method of the soft ferrite core, the grinding machine is provided with guide rails which facilitate the neat arrangement of the magnetic cores; the guide rails are parallel double guide rails; the height of the guide rails is designed according to the size of the processed magnetic cores . The assembly shaft of the grinding machine includes a horizontal shaft of the grinding machine driven by a driving motor, the flange size of the horizontal shaft of the grinding machine is increased from the current 16 mm to a width of 20-35 mm (adjusted according to the number of magnetic core processing rows), and the power of the driving motor reaches 2.2 mm. More than KW.

Compared with the prior art, the grinding method of the soft ferrite magnetic core of the present invention, on the grinding machine, the magnetic cores are arranged in double or multiple rows longitudinally, and the arranged magnetic cores are first plane-processed and then air-processed with the same grinding machine. Gap machining method. The invention fully realizes double-row or multi-row processing of ferrite magnetic core planes and air gaps. The production efficiency is greatly improved, and at the same time, the dimensional processing accuracy and inductance consistency of the magnetic core are guaranteed to meet customer requirements. After 30 days and more than 20 batches of verification, the average quality level is as follows: processing accuracy: inductance L±3%, CPK=1.58; size ±0.10mm, CPK=2.03; stand-alone production capacity: more than 30K pay/hour. The production capacity of products of the same specification is increased to more than 200%, the consistency of product inductance is improved, and the processing accuracy is good, which proves that the present invention has reliability and repeatability.

Description of drawings

Figure 1 is a schematic cross-sectional view of a grinding machine for plane processing of two rows of magnetic cores;

Figure 2 is a schematic cross-sectional view of the grinding machine for air gap machining of two rows of magnetic cores;

Fig. 3 is a schematic cross-sectional view of a grinding machine for plane processing of three rows of magnetic cores;

Figure 4 is a schematic cross-sectional view of the grinding machine for air gap machining of three rows of magnetic cores;

Fig. 5 is a cross-sectional view of a magnetic core without grinding;

Fig. 6 is the cross-sectional view of the magnetic core after grinding the middle plane;

Figure 7 is a cross-sectional view of the magnetic core after grinding the middle plane and air gap processing;

Among them, 1 grinding machine, 2 flat grinding wheel, 3 air gap grinding wheel, 21 flat grinding wheel base, 22 flat grinding wheel cutting surface, 31 air gap grinding wheel base, 32 air gap grinding wheel cutting surface, 4 guide rail, 5 magnetic core, 6 magnetic core processing air gap surface.

Detailed ways

The gist of the present invention is to innovate the plane grinding wheel and the grinding air-gap grinding wheel, improve the assembly axis of the machine tool, and at the same time transform the grinding machine tool, increase the angle adjustment function, and adopt the double guide rail fixing process to completely realize the ferrite Double-row or multi-row processing of body magnetic core plane and air gap. The production efficiency is greatly improved, and at the same time, the dimensional processing accuracy and inductance consistency of the magnetic core are guaranteed to meet customer requirements. The content of the present invention will be further described in detail with reference to the drawings and embodiments.

Embodiment 1: As shown in Fig. 1-2, 5-7, a kind of special equipment for soft ferrite core grinding method, it includes grinding machine tool 1, the upper end of the grinding machine tool is provided with the grinding machine assembly shaft, and the receiving logic is assembled on the grinding machine assembly shaft The plane grinding wheel 2 and the air gap grinding wheel 3 controlled by the controller PLC; the plane grinding wheel is provided with a plane grinding wheel base 21 and a plane grinding wheel cutting surface 22 at the front end of the plane grinding wheel base; the air gap grinding wheel 3 is provided with an air gap The air gap grinding wheel cutting surface 32 at the front end of the grinding wheel base 31 and the air gap grinding wheel base, the air gap grinding wheel cutting surface 32 is two, the air gap grinding wheel cutting surface 32 and the magnetic core processing air gap surface 6 described in Fig. 2 It is one-to-one correspondence. The grinding machine tool 1 is provided with double guide rails 4 to facilitate the neat arrangement of magnetic cores. The assembly shaft of the grinding machine includes a horizontal shaft of the grinding machine driven by a driving motor, the flange size of the horizontal shaft of the grinding machine increases from the current 16mm to a width of 25mm, and the power of the driving motor reaches 2.2±0.2KW. On the grinding machine 1, the magnetic cores are arranged longitudinally in double rows along the double guide rails, and the same grinding machine is used to process the arranged magnetic cores on the plane and then to process the air gap. This sequence is controlled by the logic controller PLC. Figure 5 is a cross-sectional view of the magnetic core without grinding. From Figure 5, it can be seen that there are many burrs on the side column and the inner column of the magnetic core. Figure 6 is a cross-sectional view of the magnetic core after grinding. Flat and smooth; Figure 7 is a cross-sectional view of the magnetic core after grinding the plane and air gap. From Figure 7, it can be seen that the core column of the magnetic core has been cut short. Its processing precision: inductance L±3%, CPK=1.58; size ±0.10mm, CPK=2.11; stand-alone production capacity: 30K pay/hour.

Embodiment 2: As shown in Fig. 3-7, a kind of special equipment of soft magnetic ferrite core grinding method, it comprises grinding machine tool 1, the upper end of grinding machine tool is provided with grinding machine assembly axis, is equipped with on the grinding machine assembly axis and is controlled by logic controller PLC The plane grinding wheel 2 and the air gap grinding wheel 3; the plane grinding wheel is provided with the plane grinding wheel base 21 and the plane grinding wheel cutting surface 22 at the front end of the plane grinding wheel base; the air gap grinding wheel 3 is provided with the air gap grinding wheel base 31 With the air gap grinding wheel cutting surface 32 at the front end of the air gap grinding wheel base, the air gap grinding wheel cutting surface 32 is 3, and the air gap grinding wheel cutting surface 32 described in Fig. 3 is one-to-one correspondence with the magnetic core processing air gap surface 6 of. The grinding machine tool 1 is provided with double guide rails 4 to facilitate the neat arrangement of magnetic cores. The assembly shaft of the grinding machine includes a horizontal shaft of the grinding machine driven by a driving motor, the flange size of the horizontal shaft of the grinding machine is increased from 16mm to 27mm in width, and the power of the driving motor reaches 2.5±0.2KW. On the grinding machine 1, the magnetic cores are arranged vertically in three rows along the double guide rails, and the same grinding machine is used to process the arranged magnetic cores on the plane and then the air gap. This sequence is controlled by the logic controller PLC. Figure 5 is a cross-sectional view of the magnetic core without grinding. From Figure 5, it can be seen that there are many burrs on the side column and the inner column of the magnetic core. Figure 6 is a cross-sectional view of the magnetic core after grinding. Flat and smooth; Figure 7 is a cross-sectional view of the magnetic core after grinding the plane and air gap. From Figure 7, it can be seen that the core column of the magnetic core has been cut short. Its processing precision is: inductance L±3%, CPK=1.56; size ±0.10mm, CPK=2.03; stand-alone production capacity: 45K pay/hour.

Claims (6)

1. the Ginding process of a soft-magnetic ferrite core is characterized in that: carry out magnetic core double on lapping machine or arrange longitudinal arrangement more, with same the grinding machine method that air gap processing is carried out in advanced parallel planes processing again to the magnetic core that arranges.

2. the Ginding process of soft-magnetic ferrite core according to claim 1, it is characterized in that: described magnetic core is double along parallel two guide rail directions or arranges longitudinal arrangement more.

3. equipment that is exclusively used in claim 1 or 2 described soft-magnetic ferrite core Ginding process, it comprises that lapping machine (1), lapping machine upper end arrange the grinding machine assembled shaft, are equipped with flat-faced wheel (2) and the air gap emery wheel (3) that is subjected to logic controller PLC control in the grinding machine assembled shaft; Described flat-faced wheel is provided with the flat-faced wheel cutting face (22) of flat-faced wheel pedestal (21) and flat-faced wheel pedestal front end; Described air gap emery wheel (3) is provided with the air gap emery wheel cutting face (32) of air gap emery wheel pedestal (31) and air gap emery wheel pedestal front end, it is characterized in that: described air gap emery wheel cutting face (32) is two or equidistant a plurality of.

4. the special equipment of soft-magnetic ferrite core Ginding process according to claim 3, it is characterized in that: described lapping machine (1) is provided with the guide rail (4) that makes things convenient for the magnetic core proper alignment.

5. the special equipment of soft-magnetic ferrite core Ginding process according to claim 4, it is characterized in that: described guide rail is parallel two guide rails.

6. according to claim 4 or the special equipment of 5 described soft-magnetic ferrite core Ginding process, it is characterized in that: described grinding machine assembled shaft comprises the grinding machine transverse axis that is driven by drive motor, the flange size of described grinding machine transverse axis is 20～35mm width, and described drive motor power reaches more than the 2.2KW.

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