CN212783054U - Pneumatic pressing device for preparing small-size sintered neodymium-iron-boron multi-pole magnetic ring - Google Patents

Abstract

The utility model discloses a pneumatic suppression device of preparation small-size sintering neodymium iron boron multipolar magnetic ring belongs to permanent magnet material preparation technical field. The device comprises an orientation mechanism and a pressing die, wherein the orientation mechanism consists of an even number of sintered neodymium-iron-boron magnetic tiles which are uniformly distributed at intervals along the circumferential direction, a die mounting cavity is formed between the sintered neodymium-iron-boron magnetic tiles in a surrounding mode, and the pressing die is correspondingly mounted in the die mounting cavity. Adopt the technical scheme of the utility model the multipolar magnetic ring of small-size sintering neodymium iron boron can effectively be manufactured, its manufacturing process is comparatively convenient, and equipment input cost is lower, and the multistage magnetic ring magnetic property that makes is better, has also improved its suppression qualification rate and whole efficiency simultaneously.

Description

Pneumatic pressing device for preparing small-size sintered neodymium-iron-boron multi-pole magnetic ring

Technical Field

The utility model belongs to the technical field of permanent magnet material preparation, more specifically the pneumatic suppression device of preparation small-size sintering neodymium iron boron multipole magnetic ring that says so designs.

Background

The sintered NdFeB multi-pole magnetic ring is a new product developed in recent years, is a new direction for the development of sintered NdFeB permanent magnet materials, is mainly applied to high-performance permanent magnet motors and sensors, has the advantages of high precision, stable operation, low noise and the like, is a first choice for controlling the motors at high rotating speed and high precision, and is widely applied to the fields of automation, digitization, intelligent equipment and the like of industrial equipment such as high-speed driving motors, servo motors and the like.

Compared with the traditional magnetic ring formed by splicing a plurality of tile-shaped magnetic blocks, the sintered NdFeB multi-pole magnetic ring has the following advantages: the overall magnetic performance is improved by 40-60%, the material utilization rate is high, and the manufacturing period is short. However, the manufacturing of the small-sized sintered neodymium iron boron multi-pole magnet ring is few at present, and the production technical difficulties mainly exist in the design of an oriented magnetic field and the design of a pressing mode under the orientation of the magnetic field. In the prior art, a pulse magnetic field orientation mode and a hydraulic pressing mode are mainly adopted to produce a multi-pole magnetic ring, a coil of a magnetic field press is arranged outside a die, and a current is introduced to the coil to provide a magnetic field, so that sintered neodymium iron boron powder in the die is oriented, the equipment investment cost is high, the coil power consumption is high, and when a small-size multi-pole magnetic ring is produced, the plurality of coils are difficult to arrange due to the small size of the magnetic ring, so that the small-size multi-pole magnetic ring cannot be effectively produced; meanwhile, the distribution of the oriented powder in the die is disturbed by adopting a pulse magnetic field orientation mode, and the magnetic performance of the die is relatively poor; and the size precision of the control is lower when the hydraulic pressing mode is adopted for pressing, the pressed blank is easy to crack or not be formed, and the pressing qualified rate and the whole efficiency are lower.

Through search, the application with the Chinese patent application number of 201210265156.3 discloses a die for a radiation-oriented sintered neodymium-iron-boron magnetic ring and a manufacturing process thereof, wherein the die comprises a magnetic conductive magnetism gathering ring, a female die, an upper pressure head assembly and a lower pressure head assembly, the female die is arranged in the magnetic conductive magnetism gathering ring, the upper pressure head assembly and the lower pressure head assembly are arranged in the female die, pressing surfaces of the upper pressure head assembly and the lower pressure head assembly are arranged oppositely, and the area of the pressing surfaces of the upper pressure head assembly and the lower pressure head assembly is the same as the cross-sectional area of a cavity of the female die. The manufacturing process comprises the following steps: 1. the upper pressure head component is lifted to the highest; 2. putting the magnetic powder into a cavity of the female die; 3. pressing the magnetic powder into a magnetic cake; 4. removing the magnetic field; 5. lifting out the cavity of the female die; 6. taking out the magnetic cake; 7. carrying out isostatic pressing; 8. trepanning; 9. and (4) finishing. Although the magnetic ring can be manufactured, the application mainly designs a pressing die for sintering the neodymium iron boron magnetic ring, an orientation device of the magnetic ring is not described much, the neodymium iron boron powder in the die can be oriented by adopting a pulsed magnetic field orientation mode, and the overall design of the magnetic ring needs to be further improved.

SUMMERY OF THE UTILITY MODEL

1. Problems to be solved

The utility model aims to solve the problem that the existing method of adoption makes the multipolar magnetic ring of small-size sintering neodymium iron boron inconvenient to make, its magnetic performance is relatively poor, and suppression qualification rate and inefficiency, provide a pneumatic suppression device of preparation multipolar magnetic ring of small-size sintering neodymium iron boron. Adopt the technical scheme of the utility model the multipolar magnetic ring of small-size sintering neodymium iron boron can effectively be manufactured, its manufacturing process is comparatively convenient, and equipment input cost is lower, and the multistage magnetic ring magnetic property that makes is better, has also improved its suppression qualification rate and whole efficiency simultaneously.

2. Technical scheme

In order to solve the above problem, the utility model discloses the technical scheme who adopts as follows:

the utility model discloses a pneumatic suppression device of preparation small-size sintered neodymium iron boron multipole magnetic ring, including orientation mechanism and embossing mold utensil, wherein orientation mechanism comprises even number along the even interval distribution's of circumferencial direction sintered neodymium iron boron magnetic shoe, centers on forming the die holding chamber between the sintered neodymium iron boron magnetic shoe, and the embossing mold utensil correspondence is installed in the die holding intracavity.

Furthermore, the pressing die comprises an upper pressing head, a lower pressing head and a die cavity, the die cavity is arranged in the die installation cavity, the upper pressing head is correspondingly arranged above the die cavity, the lower pressing head is correspondingly arranged below the die cavity, the pressing surface area of the upper pressing head and the pressing surface area of the lower pressing head are matched with the cross section area of the die cavity, the upper pressing head and the lower pressing head are respectively fixedly connected with a first air cylinder and a second air cylinder corresponding to the upper pressing head and the lower pressing head, and the air cylinders are used for driving the upper pressing head.

Furthermore, the sintered NdFeB magnetic tiles comprise four sintered NdFeB magnetic tiles which are uniformly distributed at intervals along the circumferential direction.

Furthermore, the sintered neodymium iron boron magnetic tile is fixedly arranged inside the magnetic tile fixing ring.

Furthermore, be equipped with in the solid fixed ring of magnetic shoe with the quantity and the size assorted draw-in groove of sintered neodymium iron boron magnetic shoe, the sintered neodymium iron boron magnetic shoe is installed in the draw-in groove and along the solid fixed ring's of magnetic shoe circumferencial direction evenly distributed.

Furthermore, orientation mechanism and embossing mold utensil are installed on supporting platform, supporting platform includes fixed backup pad and the supporting leg that links to each other, and orientation mechanism passes through fixed block fixed mounting in the backup pad, be equipped with in the backup pad with the orientation mechanism in the corresponding hole of dodging of embossing hole size position of die cavity, the lower pressure head can pass and dodge the hole in the backup pad and move from top to bottom along the die cavity.

Furthermore, the supporting legs comprise a plurality of supporting legs, each supporting leg is fixedly connected with a corresponding third cylinder piston, and the third cylinder is used for driving the supporting platform to move up and down.

3. Advantageous effects

Compared with the prior art, the beneficial effects of the utility model are that:

(1) the utility model discloses a preparation small-size sintering neodymium iron boron multipole magnetic ring's pneumatic suppression device, through self-control orientation mechanism, and obtain pneumatic suppression device with its and corresponding embossing mold utensil assembly, utilize this pneumatic suppression device to carry out the briquetting to sintering neodymium iron boron powder, thereby can effectively produce small-size sintering neodymium iron boron multipole magnetic ring, it is for traditional manufacturing method, the manufacturing process is comparatively convenient, equipment input cost is lower, the multistage magnetic ring magnetic performance that makes is better, and dimensional control is accurate during the suppression, its suppression qualification rate and overall efficiency have obtained effective improvement.

(2) The utility model discloses a pneumatic suppression device of preparation small-size sintering neodymium iron boron multipolar magnetic ring, through carrying out the optimal design to the concrete structure of embossing mold utensil, adopt the cylinder to drive upper pressure head and lower pressure head respectively and reciprocate, carry out two-way compression moulding to the sintering neodymium iron boron powder in the die cavity, adopt the cylinder drive to compare in hydraulic drive on the one hand, its dimensional control precision is higher, be difficult to cause the pressed compact fracture or not shaping, its pressing efficiency and suppression qualification rate have all been effectively improved; on the other hand, the two-way pressing mode is adopted, the density of the manufactured magnetic ring is more uniform, and the product quality is stable and reliable.

(3) The utility model relates to a pneumatic pressing device for preparing a small-size sintered NdFeB multi-pole magnetic ring, by optimally designing the orientation mechanism, the sintered Nd-Fe-B magnetic tiles are arranged in the clamping grooves in the magnetic tile fixing ring and are uniformly distributed along the circumferential direction of the magnetic tile fixing ring by adopting the magnetic tile fixing ring and the sintered Nd-Fe-B magnetic tile self-made permanent magnet orientation mechanism, thereby being capable of utilizing the sintered NdFeB magnetic tiles to orient the sintered NdFeB powder in the die cavity, avoiding the problems that the small-size sintered NdFeB multi-pole magnetic ring is difficult to arrange and the power consumption is large in the traditional production method adopting a coil, meanwhile, the permanent magnetic field is provided, the problem that the magnetic performance of the manufactured magnetic ring is poor due to the adoption of a pulse magnetic field orientation mode is avoided, the magnetic property is better, the orientation device is simple and effective, the magnetic shoes are distributed uniformly and symmetrically, and the surface magnetic distribution uniformity of the produced magnetic ring is ensured. And a gap is arranged between the adjacent sintered neodymium iron boron magnetic tiles, so that the demagnetization phenomenon caused by the closed circuit of the magnetic tiles is avoided.

(4) The utility model discloses a pneumatic suppression device of preparation small-size sintering neodymium iron boron multipole magnetic ring, through installing orientation mechanism and embossing mold utensil on supporting platform, and link to each other supporting platform and cylinder, when taking out the pressed compact, through keeping the lower pressure head motionless, break away from the die cavity with last pressure head upward movement, break away from the die cavity until the pressed compact with supporting platform downstream again, thereby can effectively take out the pressed compact, its lower pressure head length is appropriate, compare in the long and thin lower pressure head ejection pressed compact of tradition adoption, the hardness of lower pressure head has been guaranteed, and then the suppression effect has also been guaranteed. The manufacturing process is simple and convenient, the device has a simple structure and lower cost, and the batch production of the small-size multi-pole magnetic ring can be realized.

Drawings

Fig. 1 is a schematic structural view of a pneumatic pressing device of the present invention;

fig. 2 is a schematic structural view of an orientation mechanism of the present invention;

fig. 3 is a schematic structural view of the magnetic conductive ring of the present invention;

fig. 4 is a schematic structural view of the sintered nd-fe-b magnetic tile of the present invention;

fig. 5 is a schematic view of the magnetic performance of the sintered ndfeb quadrupole magnet ring manufactured by the pneumatic pressing device of the present invention;

fig. 6 is a schematic diagram of the gap size in the orientation mechanism for the orientation effect of the sintered nd-fe-b magnetic field.

In the figure: 1. an orientation mechanism; 11. a magnetic shoe fixing ring; 111. an accommodating chamber; 112. a card slot; 113. a magnetic tile binding surface; 114. a clearance reservation surface; 115. a clamping section; 12. sintering the neodymium iron boron magnetic tiles; 121. an outer bonding surface; 122. an inner bonding surface; 123. a clamping surface; 124. a connecting surface; 13. a die mounting cavity; 14. a gap; 2. an upper pressure head; 3. a lower pressure head; 4. a mold cavity; 5. a fixed block; 6. a support platform; 61. a support plate; 62. and (5) supporting legs.

Detailed Description

At present, the manufacturing of small-size sintered NdFeB multi-pole magnetic rings is few, and the production technical difficulty mainly exists in the design of an oriented magnetic field and the design of a pressing mode under the orientation of the magnetic field. The method mainly adopts a pulse magnetic field orientation mode and a hydraulic pressing mode to produce the multi-pole magnetic ring, when a magnetic field press is adopted for pressing, two coils of the press are arranged outside a die, a magnetic field is provided for the coils by introducing current, so that sintered neodymium iron boron powder in the die is oriented, the coils are large in power consumption and heat and need to be cooled by a matched water cooling device, and the conventional press is usually only provided with two coils, most of the produced magnetic rings are two-stage, if a small-size multi-pole magnetic ring is produced, the produced magnetic ring is small in size, the plurality of coils are difficult to arrange, the small-size multi-pole magnetic ring cannot be effectively produced, the whole process is complicated, and the equipment investment cost is high. In addition, in the prior art, the multi-pole magnetic ring is produced by adopting a pulse magnetic field orientation mode, so that the distribution of oriented powder in a die can be disturbed, and the magnetic performance is relatively poor; when the hydraulic pressing mode is adopted for pressing, the control precision of a hydraulic system of the press is poor, the phenomena of blank cracking, no forming and the like are easily caused, and the pressing qualified rate and the whole efficiency are low.

To above problem, the utility model provides a pneumatic suppression device of preparation small-size sintering neodymium iron boron multipole magnetic ring, it is right to combine specific embodiment below the utility model discloses further describe.

Example 1

The pneumatic pressing device for preparing the small-size sintered neodymium iron boron multi-pole magnetic ring comprises an orientation mechanism 1 and a pressing die, wherein the orientation mechanism 1 consists of an even number of sintered neodymium iron boron magnetic tiles 12 which are uniformly distributed at intervals along the circumferential direction, a die mounting cavity 13 is formed between the sintered neodymium iron boron magnetic tiles 12 in a surrounding mode, and the pressing die is correspondingly mounted in the die mounting cavity 13, as shown in fig. 1 and 2. Through self-control orientation mechanism 1 to make pneumatic suppression device with its and corresponding embossing mold assembly, utilize this pneumatic suppression device to carry out the compression moulding to sintering neodymium iron boron powder, thereby can effectively manufacture the multipolar magnetic ring of small-size sintering neodymium iron boron, solve the inconvenient problem of present small-size sintering neodymium iron boron multipolar magnetic ring preparation, it is for traditional manufacturing approach, the manufacturing process is comparatively convenient, equipment input cost is lower, the multistage magnetic ring magnetic property that makes is better, and size control is accurate during the suppression, its suppression qualification rate and overall efficiency have effectively been improved.

As shown in fig. 1, the pressing mold comprises an upper pressing head 2, a lower pressing head 3 and a mold cavity 4, wherein the mold cavity 4 is a circular ring-shaped mold cavity and is made of a non-magnetic hard alloy material, so that the service life of the mold can be prolonged, and the orientation magnetization field strength of powder during pressing can be improved. The die cavity 4 is arranged in the die installation cavity 13 of the orientation mechanism 1 and is attached to the inner attaching surface 122 of the sintered neodymium iron boron magnetic tile 12; the upper pressure head 2 is correspondingly arranged above the die cavity 4, a first cylinder is also fixedly arranged above the upper pressure head 2, the upper end of the upper pressure head 2 is fixedly connected with a piston of the first cylinder, and the first cylinder is used for driving the upper pressure head 2 to move up and down in the die cavity 4; the lower pressure head 3 is correspondingly installed below the die cavity 4, the lower pressure head 3 is fixedly installed with a second cylinder, the lower end of the lower pressure head 3 is fixedly connected with a piston of the second cylinder, the lower pressure head 3 is driven by the second cylinder to move up and down in the die cavity 4, the pressing surface area of the upper pressure head 2 and the lower pressure head 3 is matched with the cross sectional area of the die cavity 4, the upper pressure head 2 and the lower pressure head 3 are driven by the cylinders to move up and down respectively, the size control precision is higher compared with the traditional hydraulic driving, and the pressing efficiency and the pressing qualified rate are effectively improved.

As shown in fig. 2, the sintered ndfeb magnetic shoe 12 is fixedly installed inside the magnetic shoe fixing ring 11, the magnetic shoe fixing ring 11 is made of a magnetic conductive material (such as pure iron), the sintered ndfeb magnetic shoe 12 can be made of N52 high remanence sintered ndfeb, and the higher the remanence is, the better the magnetic field orientation of the pressed powder is; the fixed ring of magnetic shoe 11 is equipped with the draw-in groove 112 with the quantity and the size assorted of sintered neodymium iron boron magnetic shoe 12 in, and sintered neodymium iron boron magnetic shoe 12 installs in draw-in groove 112 and along the solid fixed ring of magnetic shoe 11's circumferencial direction evenly distributed. The permanent magnet orientation mechanism 1 is self-made by adopting the magnetic shoe fixing ring 11 and the sintered neodymium iron boron magnetic shoe 12, so that a permanent magnetic field is provided, on one hand, the sintered neodymium iron boron powder in the die cavity 4 can be oriented by utilizing the sintered neodymium iron boron magnetic shoe 12, the problems that the small-size sintered neodymium iron boron multipolar magnetic ring is difficult to arrange and has high power consumption in the traditional production method of coils are solved, on the other hand, the problem that the magnetic performance of the manufactured magnetic ring is poor due to the adoption of a pulse magnetic field orientation mode is also solved, and the manufactured magnetic ring has good magnetic; and the sintered neodymium iron boron magnetic tiles 12 are uniformly and symmetrically distributed along the circumferential direction of the magnetic tile fixing ring 11, so that the uniform surface magnetic distribution of the produced magnetic ring is ensured. A gap 14 is formed between the adjacent sintered NdFeB magnetic tiles 12, the center of the magnetic tile fixing ring 11 is surrounded by the sintered NdFeB magnetic tiles 13 to form a die mounting cavity 13, and the gap 14 is formed, so that the demagnetization phenomenon caused by the closed circuit of the magnetic tiles can be avoided.

Specifically, as shown in fig. 3 (fig. 3 is a schematic structural view of a magnetic shoe fixing ring 11 of a four-stage magnetic ring orientation mechanism), an accommodating cavity 111 is provided in the magnetic shoe fixing ring 11 and is used for installing a sintered neodymium-iron-boron magnetic shoe 12; the inner wall of the magnetic shoe fixing ring 11 (namely the cavity wall of the accommodating cavity 111) is provided with arc-shaped magnetic shoe attaching surfaces 113, the number and the size of which are matched with those of the sintered neodymium iron boron magnetic shoes 12, and the magnetic shoe attaching surfaces 113 are uniformly and symmetrically distributed along the circumferential direction of the magnetic shoe fixing ring 11; a gap reserved surface 114 is arranged between the adjacent magnetic shoe binding surfaces 113, the gap reserved surface 114 is connected with the magnetic shoe binding surfaces 113 through clamping sections 115, namely the clamping sections 115 are arranged at two ends of each magnetic shoe binding surface 113, and the magnetic shoe binding surfaces 113 and the clamping sections 115 at the two ends form a clamping groove 112 together. As shown in fig. 4 (fig. 4 is a schematic structural diagram of a sintered ndfeb magnetic shoe 12 of a four-level magnetic ring orientation mechanism), the sintered ndfeb magnetic shoe 12 is a fan-shaped structure, and includes an outer abutting surface 121, an inner abutting surface 122, a clamping surface 123 and a connecting surface 124, the outer abutting surface 121 matches in shape and size with the magnetic shoe abutting surface 113 of the magnetic shoe fixing ring 11, and can be abutted on the magnetic shoe abutting surface 113, the inner abutting surface 122 is abutted on the outer wall of the mold cavity 4, the clamping surface 123 is disposed at two ends of the inner abutting surface 122, and can be abutted on the clamping section 115, two ends of the connecting surface 124 are respectively connected to the clamping section 115 and the inner abutting surface 122, the gap 14 is defined by the connecting surfaces 124 close to the two sintered ndfeb magnetic shoes 12, so that the sintered ndfeb magnetic shoes 12 are tightly adsorbed in the clamping groove 112 of the magnetic shoe fixing ring 11, the sintered ndfeb magnetic shoes 12 can be, the demagnetization caused by the closed circuit of the sintered neodymium iron boron magnetic shoe 12 is avoided. The part of the gap 14 close to the die mounting cavity 13 is wider, and the part close to the inner wall of the magnetic shoe fixing ring 11 is narrower, so that the orientation effect of the magnetic shoe fixing ring on the sintered neodymium iron boron magnetic field can be further effectively improved, and the specific contrast effect is shown in fig. 6.

The orientation mechanism 1 has different device designs due to different sizes and different numbers of poles of the magnetic rings of the special-shaped neodymium iron boron in each direction, for example, four sintered neodymium iron boron magnetic shoes 12 are required to be uniformly and symmetrically arranged in the magnetic shoe fixing ring 11 for a four-stage magnetic ring, six sintered neodymium iron boron magnetic shoes 12 are required to be uniformly and symmetrically arranged in the magnetic shoe fixing ring 11 for a six-stage magnetic ring, and the orientation mechanism and the pressing mold required by the magnetic rings with different sizes are different, so that the orientation mechanism can be manufactured by self according to requirements.

Orientation mechanism 1 and embossing mold utensil are installed on supporting platform 6, and the embossing mold utensil is installed in the centre of orientation mechanism 1, supporting platform 6 includes fixed backup pad 61 and the supporting leg 62 that links to each other, and orientation mechanism 1 passes through 5 fixed mounting of fixed block on backup pad 61, be equipped with in the backup pad 61 with orientation mechanism 1 in the corresponding hole of dodging of embossing hole size position of die cavity 4, lower pressure head 3 can pass and dodge the hole and move from top to bottom along die cavity 4 in the backup pad 61. The supporting legs 62 comprise a plurality of, usually 4, and each supporting leg 62 is fixedly connected with a corresponding third cylinder piston, and the third cylinder is used for driving the supporting platform 6 to move up and down. When the traditional pressed blank is demolded, the pressed blank is usually ejected by upward movement of the lower pressing head 3, and if the pressed blank is ejected by a long stroke, the lower pressing head 3 is slender, so that the hardness of the pressed blank is insufficient, and the pressing effect is influenced; and the utility model discloses utilize the whole downstream of cylinder drive supporting platform 6 and orientation mechanism 1, take out the pressed compact, ensured that the 3 length of lower pressure head is appropriate, compare in traditional approach, guaranteed the hardness of lower pressure head 3, and then also guaranteed the suppression effect. The pneumatic pressing device is positioned in the closed box body, nitrogen is filled in the closed box body, and the sintered neodymium iron boron powder is prevented from being oxidized in the pressing process through the nitrogen.

Example 2

The pneumatic pressing device for preparing the small-size sintered neodymium iron boron multi-pole magnetic ring is basically the same as that in the embodiment 1 in structure, the pneumatic pressing device is specifically used for manufacturing the small-size sintered neodymium iron boron multi-pole magnetic ring, and the manufacturing method comprises the following steps:

the sintered Nd-Fe-B powder is produced first, and the powder of brand number N35UH is produced through the procedures of proportioning, smelting, hydrogen breaking and powder making (the production process is the existing mature process, so the description is not repeated here). And then weighing the prepared sintered neodymium iron boron powder in a closed box with the oxygen content lower than 300ppm, and carrying out vacuum packaging treatment to prevent the sintered neodymium iron boron powder from being oxidized by contacting with air. Then utilize the second cylinder to move lower pressure head 3 to the lower limb department in the die cavity 4, utilize first cylinder to go up pressure head 2 upward movement and break away from die cavity 4, put into die cavity 4 after tearing the bag to the sintered neodymium iron boron powder of weighing, utilize first cylinder to go up pressure head 2 downward movement to the upper limb department in die cavity 4, utilize two cylinders to drive simultaneously last pressure head 2 and the motion of lower pressure head 3 at last, carry out two-way press forming. By adopting a bidirectional pressing mode, the density of the manufactured magnetic ring is more uniform, and the product quality is stable and reliable.

And taking out the pressed blank after the pressing is finished, keeping the lower pressing head 3 still, utilizing the first cylinder to upwards move the upper pressing head 2 to separate from the die cavity 4, then driving the supporting leg 62 of the supporting platform 6 to downwards move through the third cylinder, so as to drive the supporting plate 61 and the orientation mechanism 1 fixed on the supporting plate 61 to downwards move until the pressed blank is separated from the die cavity 4, and taking out the pressed blank and carrying out vacuum packaging treatment on the pressed blank.

Carrying out vacuum packaging on the obtained pressed blank in a bag removing box with the oxygen content of less than 300ppm, taking out the vacuum-packaged pressed blank for isostatic pressing treatment, removing the bag in the bag removing box with the oxygen content of less than 300ppm after the treatment, taking out the pressed blank and putting the pressed blank into a dry graphite material box, and putting the graphite material box with the pressed blank into a vacuum sintering furnace for high-temperature sintering and twice tempering treatment; the pressed compact is transferred into a vacuum sintering furnace for high-temperature sintering, the sintering temperature is 1050-1100 ℃, the heat preservation time is 3-4 hours, and inert gas or nitrogen is introduced to cool to the room temperature after the heat preservation is finished; heating to 880-920 ℃, preserving heat for 1.5-2.5 h, and introducing inert gas or nitrogen to cool to room temperature after heat preservation; then heating the mixture to 450-520 ℃ again, preserving the heat for 3-5 hours, and introducing inert gas or nitrogen to cool the mixture to room temperature after the heat preservation is finished; and discharging the sintered neodymium iron boron multipole magnetic column after the two tempering treatments are finished. The utility model discloses a temperature and time to the subsequent high temperature sintering of pressed compact and twice tempering treatment have carried out concrete optimization to can further guarantee its magnetic ring magnetic property that makes, guarantee product quality.

The obtained multi-pole magnetic pole is subjected to the processes of outer circle processing, inner circle processing (trepanning and hole milling), end face grinding, chamfering, surface treatment and the like (the treatment process is a conventional mature process, so that the description is not repeated here), and the small-size sintered neodymium iron boron multi-pole magnetic ring is obtained. The sintered Nd-Fe-B material left after trepanning can be recycled, and the material utilization rate is high.

According to the small-size sintered neodymium iron boron multi-pole magnetic ring, the magnetizing device can be customized to magnetize the four-pole magnetic ring and perform surface magnetism test by adopting a magnetic field distribution tester. For example, the magnetic performance of the manufactured four-pole magnetic ring is shown in fig. 5, and as can be seen from fig. 5, the magnetic performance of the finally manufactured four-pole magnetic ring is better.

Claims (7)

1. The utility model provides a preparation small-size sintering neodymium iron boron multipolar magnetic ring's pneumatic suppression device which characterized in that: the die comprises an orientation mechanism (1) and a pressing die, wherein the orientation mechanism (1) is composed of an even number of sintered neodymium-iron-boron magnetic tiles (12) which are uniformly distributed at intervals along the circumferential direction, a die mounting cavity (13) is formed between the sintered neodymium-iron-boron magnetic tiles (12) in a surrounding mode, and the pressing die is correspondingly mounted in the die mounting cavity (13).

2. The pneumatic pressing device for preparing the small-sized sintered NdFeB multi-pole magnetic ring as claimed in claim 1, wherein: the embossing mold utensil includes pressure head (2), pressure head (3) and die cavity (4) down, install in mould installation cavity (13) die cavity (4), go up pressure head (2) and correspond and install in die cavity (4) top, pressure head (3) are corresponding to be installed in die cavity (4) below down, the cross-sectional area phase-match of the pressing surface area of going up pressure head (2) and pressure head (3) down and die cavity (4), and go up pressure head (2) and pressure head (3) down and link to each other rather than first cylinder and the second cylinder piston that corresponds respectively is fixed, utilize the cylinder drive it to reciprocate.

3. The pneumatic pressing device for preparing the small-sized sintered NdFeB multi-pole magnetic ring as claimed in claim 2, wherein: the sintered NdFeB magnetic tiles (12) comprise four and are evenly distributed at intervals along the circumferential direction.

4. The pneumatic pressing device for preparing the small-sized sintered NdFeB multi-pole magnetic ring as claimed in any one of claims 1 to 3, wherein: the sintered neodymium iron boron magnetic tile (12) is fixedly arranged inside the magnetic tile fixing ring (11).

5. The pneumatic pressing device for preparing the small-sized sintered NdFeB multi-pole magnetic ring as claimed in claim 4, wherein: the fixed ring of magnetic shoe (11) is equipped with quantity and size assorted draw-in groove (112) with sintered neodymium iron boron magnetic shoe (12), sintered neodymium iron boron magnetic shoe (12) are installed in draw-in groove (112) and along the circumferencial direction evenly distributed of the fixed ring of magnetic shoe (11).

6. The pneumatic pressing device for preparing the small-sized sintered NdFeB multi-pole magnetic ring as claimed in any one of claims 1 to 3, wherein: orientation mechanism (1) and embossing mold utensil are installed on supporting platform (6), supporting platform (6) are including fixed backup pad (61) and supporting leg (62) that link to each other, and orientation mechanism (1) is through fixed block (5) fixed mounting on backup pad (61), be equipped with on backup pad (61) with orientation mechanism (1) in the hole of dodging that the embossing hole size position of die cavity (4) is corresponding dodge the hole, lower pressure head (3) can pass and dodge the hole on backup pad (61) along die cavity (4) up-and-down motion.

7. The pneumatic pressing device for preparing the small-sized sintered NdFeB multi-pole magnetic ring as claimed in claim 6, wherein: the supporting legs (62) comprise a plurality of supporting legs, each supporting leg (62) is fixedly connected with a corresponding third cylinder piston, and the supporting platform (6) is driven to move up and down by the third cylinder.

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