CN-115831588-B - Preparation method and system of high-density patch inductance blank

CN115831588BCN 115831588 BCN115831588 BCN 115831588BCN-115831588-B

Abstract

The invention discloses a preparation method of a high-density chip inductor blank, which relates to the field of chip inductors, and comprises the steps of performing first-stage pressing and second-stage pressing on the chip inductor blank in a prefabrication process, controlling the current positions of an upper die pressing head and a second lower die pressing head to be unchanged in the first-stage pressing process, starting the first lower die pressing head and controlling the first lower die pressing head to punch upwards at a first preset pressure, entering the second-stage pressing when the powder height at the periphery of a cavity is higher than the powder height at the center of the cavity by a preset size, keeping the first lower die pressing head to punch continuously at the first preset pressure in the second-stage pressing process, starting and controlling the upper die pressing head and the second lower die pressing head to punch downwards and upwards respectively at a second preset pressure, and adjusting the punching pressure of the first lower die pressing head to the second preset pressure and keeping the pressure when the powder height corresponding to the periphery of the cavity is equal to the powder height corresponding to the center of the cavity, so as to obtain the chip inductor blank, wherein the compaction density and magnetic permeability of the chip inductor blank are greatly improved.

Inventors

HUO LISHAN
HUANG JIAXIANG
GUO HAI
YU FAN
CHEN HONGJIE

Assignees

宁波中科毕普拉斯新材料科技有限公司

Dates

Publication Date: 20260505
Application Date: 20221108

Claims (6)

1. A preparation method of a high-density chip inductor blank is characterized in that a split pressing die is used for pressing powder into a chip inductor blank composed of a cup-shaped magnet and a cylindrical magnet arranged in the cup-shaped magnet by means of step-by-step multistage pressing, a groove is formed between the cup-shaped magnet and the cylindrical magnet, the split pressing die comprises an upper die pressing head, a middle die and a lower die pressing head, the lower die pressing head comprises a first lower die pressing head and a second lower die pressing head which are arranged in a split mode, the first lower die pressing head can penetrate through the second lower die pressing head, a cavity for preparing the chip inductor blank is formed by the upper die pressing head, the lower die pressing head and the side wall of a forming hole of the middle die, and the preparation method comprises the following steps: S1, filling a preset amount of powder into a cavity, and starting an upper die pressing head, a first lower die pressing head and a second lower die pressing head to gather the pressing heads towards the middle of the cavity until the distance value between the upper die pressing head and the second lower die pressing head is equal to a first distance; S2, performing primary pressing of powder, namely controlling the current positions of an upper die pressing head and a second lower die pressing head to be unchanged, starting the first lower die pressing head, controlling the first lower die pressing head to punch upwards at a first preset pressure, enabling the powder in a cavity to flow to the periphery side of the cavity from the center of the cavity, and entering a step S3 when the height of the powder at the periphery side of the cavity is higher than the preset size of the powder at the center of the cavity, wherein the center of the cavity is a space corresponding to a cylindrical magnet, and the periphery side of the cavity is a space corresponding to a cup-shaped magnet; And S3, pressing the powder material at a second stage, namely keeping a first lower die pressing head to continuously punch at a first preset pressure, starting and controlling an upper die pressing head and a second lower die pressing head to punch downwards and upwards respectively at a second preset pressure, at the moment, enabling the powder material in the cavity to flow to the center of the cavity from the peripheral side of the cavity, and adjusting the punching pressure of the first lower die pressing head to the second preset pressure and keeping the pressure for a preset time when the height of the powder material corresponding to the peripheral side of the cavity is consistent with the height of the powder material corresponding to the center of the cavity, so as to obtain the chip inductor blank.
2. The method for manufacturing a high-density chip inductor blank as set forth in claim 1, wherein the second preset pressure is greater than the first preset pressure, and the range of values of the first preset pressure is To the point of The value range of the second preset pressure is To the point of 。
3. The method of claim 2, wherein the first distance is greater than a predetermined height of the green chip inductor.
4. A preparation system of a high-density chip inductor blank is characterized in that a split pressing die is used for pressing powder into a chip inductor blank consisting of a cup-shaped magnet and a cylindrical magnet arranged in the cup-shaped magnet by using a step-by-step multistage pressing method, a groove is formed between the cup-shaped magnet and the cylindrical magnet, the split pressing die comprises an upper die pressing head, a middle die and a lower die pressing head, the lower die pressing head comprises a first lower die pressing head and a second lower die pressing head which are arranged in a split manner, and the first lower die pressing head can pass through the second lower die pressing head; the preparation system comprises: The preparation module is used for loading a preset amount of powder into the cavity, and starting the upper die pressing head, the first lower die pressing head and the second lower die pressing head to gather the pressing heads towards the middle of the cavity until the distance value between the upper die pressing head and the second lower die pressing head is equal to the first distance; The first-stage pressing module is used for controlling the current positions of the upper die pressing head and the second lower die pressing head to be unchanged, starting the first lower die pressing head and controlling the first lower die pressing head to punch upwards at a first preset pressure, so that powder in a cavity flows to the periphery side of the cavity from the center of the cavity, and entering a step S3 when the height of the powder at the periphery side of the cavity is higher than the preset size of the powder at the center of the cavity; The second-stage pressing module is used for keeping the first lower die pressing head to continuously punch at a first preset pressure, simultaneously starting and controlling the upper die pressing head and the second lower die pressing head to punch downwards and upwards respectively at a second preset pressure, at the moment, powder in the cavity flows to the center of the cavity from the peripheral side of the cavity, and when the height of the powder corresponding to the peripheral side of the cavity is consistent with the height of the powder corresponding to the center of the cavity, the punching pressure of the first lower die pressing head is adjusted to the second preset pressure and the pressure is maintained for a preset time period, so that the chip inductor blank is obtained.
5. The system for manufacturing a high-density chip inductor blank as set forth in claim 4, wherein said second predetermined pressure is greater than said first predetermined pressure, and wherein said first predetermined pressure has a range of values To the point of The value range of the second preset pressure is To the point of 。
6. The system of claim 5, wherein the first distance is greater than a predetermined height of the green chip inductor.

Description

Preparation method and system of high-density patch inductance blank Technical Field The invention relates to the field of patch type power inductors, in particular to a preparation method and a system of a high-density patch type inductor blank. Background The patch type power inductor is used as a basic electronic element and is widely applied to various electronic devices or electronic control circuits. At present, various electronic devices are developed in the directions of miniaturization, light weight and multifunction, and the number of the applied patch type power inductors is increased, but new requirements on miniaturization, low installation thickness, large inductance and the like are also provided for the patch type power inductors. The inductor volume is miniaturized, and inside coil occupies certain space, leads to the product outline to be little with coil fit clearance, and the powder is difficult to fill in. In addition, the existing preparation process of the patch type power inductor is often to prepare an inductor blank by directly filling powder into a die and pressing and forming the powder, and the common preparation process is to firstly make a T-shaped or I-shaped part, wire the T-shaped or I-shaped columnar bulge, then fill the powder and press the powder, and because the initial powder is in a relatively loose state, the initial powder needs to be pressed with larger pressure, and the coil is easy to deform due to the larger pressing pressure in the process. In summary, the patch inductor prepared by the existing preparation process mainly has the following problems: in the preparation process of the chip inductor, if the chip inductor is pressed by larger pressure, the coil is easy to deform due to larger pressing pressure, so that the performance is reduced, and the coil size of the chip inductor is close to the size of an inductor finished product at present, if the pressing pressure is reduced, the density of powder is too low, so that the problems of exposed coil, magnetic leakage and the like are caused, hidden hazards are generated on the reliability and the safety of the subsequent use of the inductor, and the manufacturing difficulty and the cost of the small-size inductor are greatly increased. Disclosure of Invention In order to improve the compaction density of the chip inductor and reduce the deformation quantity generated by a coil, the invention provides a preparation method of a high-density chip inductor blank, wherein a split pressing die is used for pressing powder into a chip inductor blank consisting of a cup-shaped magnet and a cylindrical magnet arranged in the cup-shaped magnet by using a step-by-step multistage pressing method; the split pressing die comprises an upper die pressing head, a middle die and a lower die pressing head, wherein the lower die pressing head comprises a first lower die pressing head and a second lower die pressing head which are arranged in a split mode, the first lower die pressing head can penetrate through the second lower die pressing head, and a cavity for preparing a chip inductor blank is formed by the upper die pressing head, the lower die pressing head and the side wall of a forming hole of the middle die. Further, the preparation method comprises the steps of: S1, filling a preset amount of powder into a cavity, and starting an upper die pressing head, a first lower die pressing head and a second lower die pressing head to gather the pressing heads towards the middle of the cavity until the distance value between the upper die pressing head and the second lower die pressing head is equal to a first distance; S2, performing primary pressing of powder, namely controlling the current positions of an upper die pressing head and a second lower die pressing head to be unchanged, starting the first lower die pressing head, controlling the first lower die pressing head to punch upwards at a first preset pressure, enabling the powder in a cavity to flow to the periphery side of the cavity from the center of the cavity, and entering a step S3 when the height of the powder at the periphery side of the cavity is higher than the preset size of the powder at the center of the cavity, wherein the center of the cavity is a space corresponding to a cylindrical magnet, and the periphery side of the cavity is a space corresponding to a cup-shaped magnet; And S3, pressing the powder material at a second stage, namely keeping a first lower die pressing head to continuously punch at a first preset pressure, starting and controlling an upper die pressing head and a second lower die pressing head to punch downwards and upwards respectively at a second preset pressure, at the moment, enabling the powder material in the cavity to flow to the center of the cavity from the peripheral side of the cavity, and adjusting the punching pressure of the first lower die pressing head to the second preset pressure and keeping the pressure for a preset time