A pressed powder magnetic core and its preparation process

Abstract

The invention discloses a novel pressed powder magnetic core and a preparation process thereof, comprising a concave magnetic core body, wherein heat dissipation holes are provided in the middle of the left and right sides of the concave magnetic core body and the middle of the winding column, the pressing equipment comprises two slide boxes, and pneumatic cylinders are provided on the surfaces of the two frame plates facing each other, molds are provided inside the two slide boxes, and the sides of the two molds facing each other pass through the corresponding slide boxes, the chamfering device comprises two power boxes, the driving ends of the two motors one pass through the corresponding power boxes and are fixedly connected with grinding wheels, the telescopic ends of the two pneumatic cylinders two are fixedly connected with one end of a pull rope, and springs are provided between the left and right sides of the small surface of the rectangular slide box and the upper surface of the bottom plate, so that the heat dissipation effect of the pressed powder magnetic core can be better, the pressing of soft magnetic powder can be more uniform, and the pressed powder magnetic core of the normal specification can be conveniently chamfered.

Description

Technical Field

[0001] The invention relates to the technical field of pressed powder magnetic cores, and specifically relates to a pressed powder magnetic core and a preparation process thereof. Background Art

[0002] A magnetic core refers to a sintered magnetic metal oxide composed of a mixture of various iron oxides. It is widely used in coils and transformers of various electronic devices. With the development of technology, electronic products are gradually developing in the direction of miniaturization and high power. The magnetic core will emit a lot of heat during operation, which will inevitably cause the electromagnetic device to heat up quickly. If the heat is not dissipated in time, the electromagnetic device will be easily damaged. Therefore, the magnetic core needs to have a good heat dissipation function. At present, the industry mostly uses the case and thermal pad to dissipate heat, but this method of heat dissipation is unstable, and the deformation of the thermal pad often causes unreliable heat dissipation. In addition, in the preparation process of magnetic core molding, in order to improve the production quality of the magnetic core, it is necessary to put forward higher requirements for the preparation device to facilitate the device to be suitable for the production of various specifications of pressed powder cores, and make the pressing force more uniform, so that the density inside the pressed powder core is more uniform. For this reason, we provide a pressed powder core and its preparation process. Summary of the invention

[0003] The object of the present invention is to provide a powder magnetic core and a preparation process thereof to solve the problems raised in the above background technology.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a compressed powder magnetic core, comprising a concave magnetic core body, a winding column is provided in the middle of the concave magnetic core body, and heat dissipation holes are provided in the middle of the left and right sides of the concave magnetic core body and the middle of the winding column.

[0005] Preferably, a heat-conducting thin tube is provided inside the heat dissipation through hole, annular heat-conducting pads are embedded at both upper and lower ends of the inner surface of the heat dissipation through hole, and the upper and lower ends of the heat-conducting thin tube are fixedly connected to the annular heat-conducting pads on the corresponding side.

[0006] A process for preparing a powder magnetic core, comprising soft magnetic powder, wherein the soft magnetic powder is used to make the concave magnetic core body, comprising the following steps:

[0007] Step 1, insulation treatment process: firstly, the surface of the particles of the soft magnetic powder is covered with an insulation film, and then the surface of the insulation film is covered with acrylic resin;

[0008] Step 2, forming process: pressurizing and forming the soft magnetic powder after the insulation treatment process in step 1;

[0009] Step 2: Heat treatment process: heat-treating the soft magnetic powder after the forming process in step 2 in an oxidizing environment.

[0010] Preferably, the forming process in step two includes a pressing device and a chamfering device, wherein the pressing device is used to press and shape the soft magnetic powder in step two, and the chamfering device is used to chamfer the soft magnetic powder in step two after pressing and shaping.

[0011] Preferably, the pressing equipment includes two frame plates and two slide boxes, a fixed plate is symmetrically arranged between the two frame plates, a mounting plate is fixedly connected between the two fixed plates, a slide groove is arranged on the front surface of the mounting plate, and the rear surfaces of the two slide boxes are slidably connected in the slide groove through sliders, and a pneumatic cylinder 1 is arranged on the back-to-back surfaces of the two frame plates, and the telescopic ends of the two pneumatic cylinders 1 penetrate the frame plates on the corresponding sides and are fixedly connected to the slide boxes on the corresponding sides, and molds are arranged inside the two slide boxes, and the facing sides of the two molds penetrate the corresponding slide boxes.

[0012] Preferably, an inner side wall of the slide box is slidably connected with a mounting groove, the mold is fixedly connected to the mounting groove by bolts, and a spring shock absorber is provided between the mounting groove and the slide box.

[0013] Preferably, the chamfering device includes a bottom plate and two power boxes, the upper surface of the bottom plate is symmetrically provided with side plates, a rectangular slide box is slidably connected between the two side plates, a groove is penetrated through the middle of the lower side wall of the rectangular slide box, the upper ends of the two power boxes are slidably connected in the groove through a slide bar, a motor 1 is provided inside the two power boxes, and the driving ends of the two motors 1 are opposite to each other, and the driving ends of the two motors 1 are fixedly connected to the corresponding power box with a grinding wheel, a motor 2 is provided on the inner right surface of the rectangular slide box, and the driving end of the motor 2 is fixedly connected to a threaded rod, and the left end of the threaded rod rotates with the inner left surface of the rectangular slide box Dynamic connection, the left and right sides of the outer surface of the threaded rod are threadedly connected with nuts, the two nuts are slidably connected to the rectangular sliding box, and the thread directions on both sides of the threaded rod are opposite, the lower ends of the two nuts are fixedly connected to the sliding bar on the power box on the corresponding side, the upper ends of the two side plates are provided with fixed pulleys, and the left and right ends of the upper surface of the bottom plate are provided with pneumatic cylinders 2, the telescopic ends of the two pneumatic cylinders 2 are fixedly connected with one end of the pull rope, and the other ends of the pull ropes pass through the fixed pulleys on the corresponding sides and are fixedly connected to the upper surface of the rectangular sliding box, and springs are provided between the left and right sides of the small surface of the rectangular sliding box and the upper surface of the bottom plate.

[0014] Compared with the prior art, the invention has the following beneficial effects: a pressed powder magnetic core and a preparation process thereof, wherein heat dissipation holes are arranged on the concave magnetic core body and the winding column, and a heat-conducting thin tube is arranged in the heat dissipation holes, so that the heat dissipation effect of the pressed powder magnetic core can be better, two slide boxes are slidably connected in the slide groove on the mounting plate, a mold is arranged in the slide box, and the two slide boxes are fixedly connected with the telescopic end of the pneumatic cylinder, so that the soft magnetic powder can be subjected to pressure on both the upper and lower sides during pressing, so that the pressing of the soft magnetic powder is more uniform, and it is also beneficial to prevent cracks from being generated inside the soft magnetic powder, and the soft magnetic powder can be pressed more evenly. The threaded rod is rotated by controlling motor 2, and nuts are provided on opposite threads on both sides of the threaded rod. The nuts are slidably connected to the inner wall of the rectangular slide box, and the two nuts can be close to or far away from each other, so that the spacing between the two grinding wheels on the lower side can be adjusted. The telescopic end of the second pneumatic cylinder is connected to one end of a pull rope, so that the pull rope slides along the fixed pulley, and the other end of the pull rope pulls the rectangular slide box. A spring is provided between the rectangular slide box and the bottom plate, so that the rectangular slide box can slide up and down with the telescopic movement of the second pneumatic cylinder, so that the compressed powder core of the general specification can be chamfered conveniently, so that the chamfering device has a wider range of application. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a three-dimensional diagram of the powder magnetic core of the present invention;

[0016] Figure 2 This is a front view of the internal structure of the powder magnetic core of the present invention;

[0017] Figure 3 A perspective view of a pressing device according to the present invention;

[0018] Figure 4 It is a front view of the pressing device of the present invention;

[0019] Figure 5 This is a front view of the internal structure of the sliding box of the pressing device of the present invention;

[0020] Figure 6 It is a front view of the chamfering device of the present invention;

[0021] Figure 7 It is a front view of the internal structure of the chamfering device of the present invention.

[0022] In the figure: 1-concave magnetic core body, 2-winding column, 3-heat dissipation through hole, 4-thermal conductive thin tube, 5-annular thermal pad, 6-frame plate, 7-fixed plate, 8-mounting plate, 9-slide groove, 10-slide box, 11-pneumatic cylinder 1, 12-mold, 13-mounting groove, 14-spring shock absorber, 15-bottom plate, 16-side plate, 17-rectangular slide box, 18-slot, 19-power box, 20-motor 1, 21-grinding wheel, 22-motor 2, 23-threaded rod, 24-nut, 25-fixed pulley, 26-pneumatic cylinder 2, 27-pull rope, 28-spring. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] See also Figure 1-7 The present invention provides the following technical solution: a pressed powder magnetic core, comprising a concave magnetic core body 1, a winding post 2 is provided in the middle of the concave magnetic core body 1, and heat dissipation holes 3 are provided in the middle of the left and right sides of the concave magnetic core body 1 and the middle of the winding post 2, and the heat dissipation holes 3 facilitate the rapid dissipation of heat, so that the heat dissipation effect of the pressed powder magnetic core is better.

[0025] Specifically, a heat-conducting thin tube 4 is provided inside the heat dissipation through hole 3, and annular heat-conducting pads 5 are embedded at both upper and lower ends of the inner surface of the heat dissipation through hole 3. The upper and lower ends of the heat-conducting thin tube 4 are fixedly connected to the annular heat-conducting pads 5 on the corresponding sides. The annular heat-conducting pads 5 are used to fix the heat-conducting thin tube 4. The heat-conducting thin tube 4 can conduct the heat generated on the pressed powder magnetic core more quickly, so that the heat dissipation effect of the pressed powder magnetic core is better.

[0026] A process for preparing a powder magnetic core, comprising soft magnetic powder, wherein the soft magnetic powder is used to make the concave magnetic core body 1, comprising the following steps:

[0027] Step 1, insulation treatment process: firstly, the surface of the particles of the soft magnetic powder is covered with an insulating film, and then the surface of the insulating film is covered with acrylic resin to make the soft magnetic powder insulated and shape-preserving.

[0028] Step 2, forming process: pressurizing the soft magnetic powder after the insulation treatment process in step 1; pressing the soft magnetic powder treated in step 1 into the shape of a magnetic core.

[0029] Step 2: Heat treatment process: heat-treating the soft magnetic powder after the forming process in step 2 in an oxidizing environment.

[0030] Specifically, the forming process in step two includes a pressing device and a chamfering device, wherein the pressing device is used to press and shape the soft magnetic powder in step two, and the chamfering device is used to chamfer the soft magnetic powder in step two after pressing and shaping.

[0031] Specifically, the pressing equipment includes two frame plates 6 and two slide boxes 10, a fixed plate 7 is symmetrically arranged between the two frame plates 6, a mounting plate 8 is fixedly connected between the two fixing plates 7, a slide groove 9 is arranged on the front surface of the mounting plate 8, and the rear surfaces of the two slide boxes 10 are slidably connected in the slide groove 9 through a slider, and a pneumatic cylinder 11 is arranged on the back-to-back surfaces of the two frame plates 6, and the telescopic ends of the two pneumatic cylinders 11 penetrate the frame plates 6 on the corresponding side and are fixedly connected to the slide boxes 10 on the corresponding side, and the two slide boxes 10 is provided with a mold 12 inside, and the two sides of the mold 12 facing each other are penetrated by the corresponding slide box 10, and the soft magnetic powder processed in step 1 is placed in the lower mold 12, and then the pneumatic cylinders 11 on the upper and lower sides are controlled to extend at the same time, so that the pneumatic cylinders 11 on both sides slide the slide boxes 10 on the upper and lower sides toward the middle together, and overlap and press them together. At this time, the upper and lower sides of the soft magnetic powder can be subjected to pressure when pressing, so that the force on the soft magnetic powder is more uniform, which is beneficial to prevent cracks from occurring inside the soft magnetic powder and achieve a better pressing effect of the pressed powder core.

[0032] Specifically, the inner wall of the slide box 10 is slidably connected with a mounting groove 13, and the mold 12 is fixedly connected to the mounting groove 13 by bolts. The mounting groove 13 and the mold 12 are convenient to disassemble so as to replace different molds 12 and press magnetic cores of different shapes. A spring shock absorber 14 is provided between the mounting groove 13 and the slide box 10. When the molds 12 on both sides are under pressure, the spring shock absorber 14 can provide buffering, which is beneficial to the protection of the mold 12.

[0033] Specifically, the chamfering device includes a bottom plate 15 and two power boxes 19, the upper surface of the bottom plate 15 is symmetrically provided with side plates 16, and a rectangular slide box 17 is slidably connected between the two side plates 16, so that the rectangular slide box 17 can slide up and down between the two side plates 16, and a slot 18 is provided through the middle of the lower side wall of the rectangular slide box 17, and the upper ends of the two power boxes 19 are slidably connected to the slot 18 through a slide bar, and the inside of the two power boxes 19 is provided with a motor 20, and the driving ends of the two motors 20 are opposite, and the driving ends of the two motors 20 are both fixed through the corresponding power box 19. A grinding wheel 21 is connected to control the rotation of motor 1 20 to rotate the grinding wheel 21 and chamfer the pressed magnetic core. A motor 22 is provided on the inner right surface of the rectangular slide box 17. A threaded rod 23 is fixedly connected to the driving end of the motor 22. The left end of the threaded rod 23 is rotatably connected to the inner left surface of the rectangular slide box 17. Nuts 24 are threadedly connected to the left and right sides of the outer surface of the threaded rod 23. The two nuts 24 are slidably connected to the rectangular slide box 17, and the thread directions on both sides of the threaded rod 23 are opposite. The lower ends of the two nuts 24 are fixedly connected to the slide bar on the power box 19 on the corresponding side. Then, the control motor 22 rotates to rotate the threaded rod 23, and the two nuts 24 on the threaded rod 23 are limited by the rectangular sliding box 17 and can slide left and right, and the threads on both sides of the threaded rod 23 are in opposite directions, so that when the two nuts 24 slide, they can approach or move away from each other, thereby making the spacing between the two grinding wheels 21 on the lower side adjustable, and the upper ends of the two side plates 16 are provided with fixed pulleys 25, and the left and right ends of the upper surface of the bottom plate 15 are provided with pneumatic cylinders 26, and the telescopic ends of the two pneumatic cylinders 26 are fixedly connected to one end of a pull rope 27, and the other end of the pull rope 27 passes through the fixed pulley 25 on the corresponding side and the The upper surface of the rectangular slide box 17 is fixedly connected, and springs 28 are provided between the left and right sides of the small surface of the rectangular slide box 17 and the upper surface of the base plate 15. The extension and retraction of the pneumatic cylinder 26 can drive the pull rope 27, and a spring 28 is provided between the rectangular slide box 17 and the base plate 15. The pneumatic cylinder 26 pushes outward, and the rectangular slide box 17 slides downward under the pull of the spring 28. The pneumatic cylinder 26 contracts, and the pull rope 27 can pull the rectangular slide box 17 to the upper side, so that the height of the grinding wheel 21 can be adjusted. In summary, the chamfering device can process pressed powder cores of different specifications, ensuring the processing effect while making the chamfering device have a wide range of applications.

[0034] Working principle: The concave magnetic core body 1 and the winding column 2 of the present invention are both provided with heat dissipation holes 3, which facilitate the generated heat to be directly dissipated outward through the heat dissipation holes 3, and the heat-conducting thin tube 4 can accelerate the heat transfer, so that the heat dissipation effect of the pressed powder magnetic core is better. In the process of producing the pressed powder magnetic core, a pressing device is used to press the soft magnetic powder, and the soft magnetic powder is placed in the lower mold 12, and the pneumatic cylinder 11 on the upper and lower sides is controlled to operate, so that the upper and lower molds 12 are close to the middle together, so that the upper and lower sides are jointly stressed when the soft magnetic powder is pressed, so that the density of the pressed powder magnetic core is more uniform, which is beneficial to prevent the occurrence of cracks, and the mold 12 and the mounting groove 13 are detachable and replaceable, which is convenient for replacing different molds 12 to press pressed powder magnetic cores of different specifications, and the mounting groove 1 A spring shock absorber 14 is provided between the slider 10 and the rectangular slider 10, which can play a good buffering role and is beneficial to the protection of the mold 12. After the pressing and forming, the chamfering device is used to chamfer the pressed powder core. The motor 22 is controlled to rotate so that the two nuts 24 on the threaded rod 23 with opposite threads and limited by the rectangular slider 17 can approach or move away from each other, thereby making the distance between the two grinding wheels 21 on the lower side adjustable, and the pneumatic cylinder 26 is telescopic to pull the pull rope 27. Under the action of the spring 28 between the rectangular slider 17 and the bottom plate 15, the rectangular slider 17 can slide up and down, thereby adjusting the height of the grinding wheel 21, so that the chamfering device can chamfer pressed powder cores of various specifications, ensuring the processing effect while making the chamfering device have a wide range of applications.

[0035] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the instructions and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the prior art. Machinery, parts and equipment all adopt conventional models in the prior art, and the circuit connection adopts the conventional connection method in the prior art, which will not be described in detail here.

[0037] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A powder magnetic core, comprising a concave magnetic core body (1), characterized in that: A winding post (2) is provided in the middle of the concave magnetic core body (1), and heat dissipation through holes (3) are provided in the middle of the left and right sides of the concave magnetic core body (1) and the middle of the winding post (2) from top to bottom; A heat-conducting thin tube (4) is provided inside the heat-dissipating through hole (3), annular heat-conducting pads (5) are embedded at both upper and lower ends of the inner surface of the heat-dissipating through hole (3), and the upper and lower ends of the heat-conducting thin tube (4) are fixedly connected to the annular heat-conducting pads (5) on the corresponding side; The preparation process of the above-mentioned powder magnetic core comprises soft magnetic powder, wherein the soft magnetic powder is used to make a concave magnetic core body (1), comprising the following steps: Step 1, insulation treatment process: firstly, the surface of the particles of the soft magnetic powder is covered with an insulating film, and then the surface of the insulating film is covered with acrylic resin; Step 2, forming process: pressurizing and forming the soft magnetic powder after the insulation treatment process in step 1; Step 2, heat treatment process: heat treating the soft magnetic powder after the forming process in step 2 in an oxidizing environment; The forming process in step 2 includes a pressing device and a chamfering device. The pressing device is used to press and shape the soft magnetic powder in step 2, and the chamfering device is used to chamfer the soft magnetic powder in step 2 after pressing and shaping.

2. A powder magnetic core according to claim 1, characterized in that: The pressing device comprises two frame plates (6) and two slide boxes (10), a fixing plate (7) is symmetrically arranged between the two frame plates (6), a mounting plate (8) is fixedly connected between the two fixing plates (7), a slide groove (9) is arranged on the front surface of the mounting plate (8), and the two The rear surface of the slide box (10) is slidably connected to the slide groove (9) through a slider, and a pneumatic cylinder (11) is provided on the back-to-back surfaces of the two frame plates (6). The telescopic ends of the two pneumatic cylinders (11) penetrate the frame plates (6) on the corresponding sides and are fixedly connected to the slide box (10) on the corresponding sides. A mold (12) is provided inside the two slide boxes (10). The facing sides of the two molds (12) both penetrate the corresponding slide box (10).

3. A powder magnetic core according to claim 2, characterized in that: The inner side wall of the slide box (10) is slidably connected to a mounting groove (13), the mold (12) and the mounting groove (13) are fixedly connected by bolts, and a spring shock absorber (14) is provided between the mounting groove (13) and the slide box (10).

4. A powder magnetic core according to claim 3, characterized in that: The chamfering device comprises a bottom plate (15) and two power boxes (19); the upper surface of the bottom plate (15) is symmetrically provided with side plates (16); a rectangular sliding box (17) is slidably connected between the two side plates (16); a slot is provided through the middle of the lower side wall of the rectangular sliding box (17); (18), the upper ends of the two power boxes (19) are slidably connected to the slot (18) through a slide bar, the interior of the two power boxes (19) is provided with a motor 1 (20), and the driving ends of the two motors 1 (20) are opposite to each other, and the driving ends of the two motors 1 (20) pass through the corresponding power box (19) and are fixedly connected to a grinding wheel (21), and the rectangular slide The inner right surface of the box (17) is provided with a second motor (22), the driving end of the second motor (22) is fixedly connected with a threaded rod (23), the left end of the threaded rod (23) is rotatably connected to the inner left surface of the rectangular sliding box (17), the left and right sides of the outer surface of the threaded rod (23) are threadedly connected with nuts (24), the two nuts (24) are slidably connected to the rectangular sliding box (17), and the threads on both sides of the threaded rod (23) are in opposite directions, and the lower ends of the two nuts (24) are connected to the upper ends of the power box (19) on the corresponding sides. The slide bar is fixedly connected, the upper ends of the two side plates (16) are each provided with a fixed pulley (25), the left and right ends of the upper surface of the bottom plate (15) are each provided with a pneumatic cylinder (26), the telescopic ends of the two pneumatic cylinders (26) are each fixedly connected to one end of a pull rope (27), the other end of the pull rope (27) passes through the fixed pulley (25) on the corresponding side and is fixedly connected to the upper surface of the rectangular slide box (17), and springs (28) are provided between the left and right sides of the lower surface of the rectangular slide box (17) and the upper surface of the bottom plate (15).

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