Constant-temperature compression molding equipment for powder magnetic core

Abstract

The invention relates to the technical field of power grid equipment manufacturing, and particularly discloses powder magnetic core constant-temperature pressing forming equipment which comprises a machine body, a rotating shaft, a die disc, an upper stamping die, a lower stamping die, a guide plate, a feeding barrel and a feeding pipe. A plurality of material grooves matched with the upper stamping die and the lower stamping die are formed in the die disc, and the machine body is fixedly connected with a mounting frame outside the die disc; a limiting frame is fixedly connected to the mounting frame, a conveying belt is arranged in the limiting frame, a plurality of coils are arranged on the conveying belt, and a temperature control assembly used for controlling the temperature of the groove wall of the material groove is arranged in the mold disc; two guide rods are fixedly connected to the mounting frame, an electric brush is fixedly connected to the coil, a feeding frame is fixedly connected to the mounting frame, a temporary storage box is fixedly connected to the end, away from the feeding pipe, of the feeding frame, a shovel plate inclining downwards is fixedly connected to the top of the end, close to the feeding pipe, of the temporary storage box, and a suction assembly used for sucking redundant magnetic powder in the temporary storage box is arranged on the machine body. The feeding device has the effect of improving the feeding uniformity and the production efficiency during thermal production.

Description

Technical Field

[0001] The present application relates to the technical field of power grid equipment manufacturing, and in particular to a constant temperature pressing and molding device for pressed powder magnetic cores. Background Art

[0002] The magnetic core refers to a sintered magnetic metal oxide composed of a mixture of various iron oxides, which is used in various coils, inductors, transformers, mutual inductors, filters and other power grids and electronic equipment.

[0003] The pressing and molding of magnetic cores is a process of uniformly mixing magnetic powder coated with insulating material on the surface, a binder and a release agent, then screening out the agglomerates in the mixture, and then putting it into a mold of a specific shape to press it into various shapes of green billets. There are many ways to press magnetic cores, including cold pressing, warm pressing, hot pressing, multi-step pressing, etc. There are many types of magnetic cores, including iron silicon magnetic powder cores, sendust magnetic powder cores, iron nickel magnetic powder cores, etc. The processing technology of different types of magnetic cores is also different. For example, the best pressing temperature of iron silicon magnetic powder cores is 150℃-200℃, and that of sendust magnetic powder cores is 150℃-250℃. During the pressing process of the iron silicon magnetic powder core, if the temperature is too low, the magnetic powder core may be insufficient in strength and cracks after pressing. If the temperature is too high, the resin coating may be burned and the performance stability may be affected.

[0004] There are also many types of magnetic powder core pressing equipment, including uniaxial presses, multi-axial presses, hot isostatic presses, powder rotary presses, etc. Among them, the powder rotary press has multiple stations for continuous production, combined with modular functions such as powder supply, pressing, demolding and collection. Compared with other types of pressing equipment, the powder rotary press has higher production efficiency and degree of automation.

[0005] With respect to the above-mentioned related technologies, the inventors believe that the following defects exist: when producing iron silicon magnetic powder cores, although the powder rotary press has a high production efficiency, it is difficult to perform high-temperature pressing of the magnetic powder; the uniaxial press can be easily modified to be suitable for high-temperature pressing, but the production efficiency is low, and whether it is a uniaxial press or a powder rotary press, during the feeding process, it is easy to cause uneven feeding and large gaps between the magnetic powders due to the influence of factors such as binders, which in turn leads to reduced stability of subsequent finished products. Summary of the invention

[0006] In order to improve the problems of uneven magnetic powder during the feeding process and low production efficiency during high-temperature pressing, the present application provides a constant temperature pressing and molding device for pressed powder magnetic cores.

[0007] The present application provides a constant temperature pressing and molding device for powder magnetic cores, which adopts the following technical solutions: A constant temperature pressing and molding device for a pressed powder magnetic core, comprising a machine body, a rotating shaft rotatably arranged on the machine body, a mold disk fixedly connected to the rotating shaft, an upper punch die lifted and arranged on the rotating shaft above the mold disk, a lower punch die lifted and arranged on the rotating shaft below the mold disk, a guide plate fixedly connected to the machine body, a feed barrel fixedly connected to the machine body and a feed pipe connected to the feed barrel, a plurality of material troughs adapted to the upper punch die and the lower punch die are provided on the mold disk, characterized in that: the machine body is fixedly connected to a mounting frame outside the mold disk, a limit frame adapted to the curvature of the mold disk is fixedly connected to the mounting frame, a conveyor belt is provided in the limit frame, a plurality of coils are provided on the conveyor belt, the input end and the output end of the coil are both fixedly connected to the conveyor belt, the center of the coil is aligned with the material trough of the mold disk and the speeds of the two are equal, and a temperature control component for controlling the trough wall temperature of the material trough is provided in the mold disk; Two guide rods are fixedly connected to the mounting frame, brushes are fixedly connected to the input and output ends of the coil, and when the conveyor belt drives the coil to move to a position close to the mold plate, the two brushes on the coil are respectively pressed against the two guide rods, and the mold plate is non-magnetic stainless steel; The mounting frame is fixedly connected to a loading frame on a side of the feed tube away from the guide plate, the loading frame is fitted with the mold plate, the loading frame is fixedly connected to an end of the feed tube away from the feed tube with a temporary storage box, the temporary storage box is fixedly connected to a shovel plate inclined downward on the top near one end of the feed tube, the shovel plate is also fitted with the mold plate, and a suction component for sucking excess magnetic powder in the temporary storage box is provided on the machine body.

[0008] By adopting the above technical scheme, the magnetic powder in the feeding barrel falls into the feeding frame through the feeding pipe. When the material trough on the mold plate moves to the bottom of the feeding frame, the magnetic powder stored in the feeding pipe and the feeding frame falls into the material trough, and the coil is also transported by the conveyor belt to the top of the material trough and moves synchronously with the corresponding material trough. At the same time, the brush on the coil is tightly attached to the guide rod. The two guide rods provide alternating current to the coil, thereby causing the coil to generate an alternating magnetic field. The magnetic powder vibrates under the action of the changing magnetic field, so that the magnetic powders are closely attached to each other. At the same time, the magnetic powder is heated due to the eddy current phenomenon. When the coil moves until the brush disengages from the guide rod and contacts the guide rod, the coil stops heating the magnetic powder. At this time, the magnetic powder reaches the waiting temperature due to the heating of the coil, completing the loading of a material trough and the heating of the magnetic powder in the material trough. The magnetic powder transported with the mold disc in the loading frame is shoveled into the temporary storage box by the shovel plate and extracted by the suction component; as the mold disc continues to rotate, the heated magnetic powder is pressed down by the upper punch to be pressed into a magnetic core. After the pressing and forming, the upper punch moves up to reset and the lower punch moves up to push out the magnetic core. When the pushed out magnetic core moves to the guide plate, the magnetic core moves to unload under the guidance of the guide plate, and then the lower punch moves down to reset. During the pressing process of the magnetic powder by the upper punch, the friction between the magnetic powder and the trough wall of the material trough will generate a lot of heat. During long-term operation, the temperature control component controls the trough wall temperature of the material trough to avoid the trough wall temperature being too high to affect the stability of the pressed magnetic core and the service life of the mold disc, and multiple stations alternately perform the steps of loading, heating, pressing, unloading, etc., and the processing efficiency is high.

[0009] Optionally, the mold plate is provided with a plurality of receiving grooves around the groove wall of each of the material grooves, and the temperature control component includes a heat-conducting box placed in the receiving groove and a phase change layer filled in the heat-conducting box, and the phase change layer is a ternary eutectic layer of sodium nitrate, potassium nitrate and sodium nitrite.

[0010] By adopting the above technical solution, the melting point of the phase change layer is adjusted by adjusting the ratio of sodium nitrate, potassium nitrate and sodium nitrite in the thermally conductive box, thereby adapting to the temperature range corresponding to different types of magnetic cores. During the magnetic powder pressing process, the temperature of the slot wall of the material slot is transferred to the thermally conductive box, and then transferred to the phase change layer by the thermally conductive box. When the temperature of the slot wall of the material slot is high, the phase change layer is heated and melted and absorbs heat, so that the slot wall of the material slot is always in a constant temperature state.

[0011] Optionally, the temperature control component also includes an air pipe opened in the peripheral wall of the heat-conducting box, a one-way air valve arranged at one end of the air pipe, an elastic membrane arranged at the other end of the air pipe, and a control component for controlling the deflation of the elastic membrane, the one-way air valve only allows gas to flow from the heat-conducting box into the air pipe, the air pipe is filled with nitrogen, and the one-way air valve is located at the top of the heat-conducting box.

[0012] By adopting the above technical solution, when the air pipe is continuously heated, the nitrogen in the air pipe expands and squeezes the elastic film. When the pressure in the air pipe is too large, the nitrogen pushes open the elastic film, so that the elastic film breaks through the pressing effect of the control component, and then the nitrogen enters the heat transfer box to generate bubbles. The molten phase change layer is affected by the disturbance of the bubbles and accelerates the flow, thereby improving the heat exchange effect between the phase change layer and the side of the heat transfer box close to the material tank. When the pressure in the heat transfer box is greater than that in the air pipe, the nitrogen enters the air pipe from the one-way valve. At the same time, due to the continuous pressing operation, the change of ambient temperature, the melting of the phase change layer and other factors, the trough wall temperature of the material tank is always dynamically changing within the specified range, that is, the temperature in the heat transfer box and the air pipe is always in dynamic change, and the pressure difference between the air pipe and the heat transfer box is also in dynamic change.

[0013] Optionally, the control component is a spring steel sheet with one end fixed to the inner bottom wall of the thermal conductive box, and the elastic membrane is divided into an adhesive portion and a fitting portion. The adhesive portion of the elastic membrane is seamlessly bonded to the inner wall of the thermal conductive box, the fitting portion of the elastic membrane is fitted to the inner wall of the thermal conductive box, and the spring steel sheet presses the fitting portion of the elastic membrane.

[0014] By adopting the above technical solution, the elastic membrane bulges due to the influence of air pressure, but the spring steel sheet presses the fitting part of the elastic membrane, causing the pressure in the air pipe to become higher and higher, until the pressure in the air pipe is greater than the restriction of the spring steel sheet on the elastic membrane. At this time, a gap appears between the fitting part of the elastic membrane and the inner wall of the heat conduction box, and nitrogen enters the phase change layer through the gap; at the same time, since the nitrogen is discharged from the air pipe, the spring steel sheet presses the elastic membrane again, completing an exhaust process.

[0015] Optionally, the air inlet end of the one-way air valve and the end of the air pipe close to the elastic membrane are both fixedly connected with a filter plate that only allows gas to pass through.

[0016] By adopting the above technical solution, the filter plate prevents the molten phase change layer in the heat conduction box from entering the air pipe through the one-way air valve and the elastic membrane end of the air pipe, thereby effectively preventing the phase change material from clogging the air pipe and the one-way air valve.

[0017] Optionally, the suction assembly includes a return pipe connected to the supply barrel, a suction pipe connected to the return pipe and a suction pipe connected to the suction pipe, the suction pipe is in a closed shape at one end close to the return pipe, the connection between the suction pipe and the suction pipe is located at the closed end of the suction pipe, the suction pipe is connected to the side wall of the temporary storage box, and the suction pipe is externally connected to an air source.

[0018] By adopting the above technical scheme, when the suction tube inhales air, when the airflow moves to the closing part of the suction tube, the airflow velocity increases and the pressure decreases due to the reduction of the aperture, that is, the pressure at one end of the suction tube close to the suction tube is less than that at one end of the suction tube close to the temporary storage box. At this time, the magnetic powder in the temporary storage box is sucked by the suction tube, and at the same time, the suction tube also sucks the magnetic powder remaining on the surface of the pressed magnetic core, so that the magnetic powder on the temporary storage box and the magnetic core are sucked to the return pipe, and finally input into the feed barrel by the return pipe to avoid the waste of magnetic powder. After the magnetic core is formed, the suction pipe also performs a certain cooling treatment on the magnetic core to reduce the accident of scalding of the staff.

[0019] Optionally, one end of the return pipe close to the supply barrel is connected to a net with a bottom opening.

[0020] By adopting the above technical solution, the magnetic powder sprayed out of the return pipe collides with the net, which reduces the speed of the magnetic powder, facilitates the magnetic powder to fall to the bottom of the feed barrel, and avoids the high-speed magnetic powder from flying around.

[0021] Optionally, a silicon steel sheet is provided at one end of the coil close to the middle of the conveyor belt.

[0022] By adopting the above technical solution, the silicon steel sheet effectively enhances the concentration and guidance of the magnetic field generated by the coil, that is, due to factors such as the global transmission of the magnetic field, the magnetic field at the end of the coil away from the silicon steel sheet also changes accordingly, which helps to guide the alternating magnetic field to the material trough, thereby reducing the leakage of the magnetic field and enhancing the movement efficiency and heating speed of the magnetic powder.

[0023] Optionally, a plurality of dividing bars whose height is lower than that of the feeding frame are fixedly connected in the feeding frame, the dividing bars are arc-shaped, and the middle portions of the dividing bars are located on the movement path of the feeding trough.

[0024] By adopting the above technical solution, when the mold disc rotates, the magnetic powder located in the feeding frame and on the mold disc is scraped into the material trough by the dividing strip, and the alternating magnetic field of the coil produces a slight vibration on the magnetic powder, so that the magnetic powder in the material trough is compacted and the surface is concave, and then it is filled up by the next dividing strip, thereby improving the final feeding effect of the material trough.

[0025] In summary, the present application includes at least one of the following beneficial technical effects: 1. When the trough and the coil correspond to each other and move synchronously, the brush on the coil is close to the guide rod, and the two guide rods provide alternating current to the coil, which in turn generates an alternating magnetic field. The silicon steel sheet enhances the concentration and guidance of the magnetic field generated by the coil. The magnetic powder vibrates under the action of the changing magnetic field, so that the magnetic powders fit closely to each other, improving the uniformity of the magnetic powder in the trough. At the same time, the magnetic powder is heated up due to the eddy current phenomenon, and the whole process has a high processing efficiency. 2. During the magnetic powder pressing process, the temperature of the slot wall of the material tank is transferred to the heat-conducting box, and then transferred to the phase change layer by the heat-conducting box. When the temperature of the slot wall of the material tank is high, the phase change layer is heated and melted and absorbs heat. At the same time, the nitrogen in the air pipe expands and squeezes the elastic film. When the pressure in the air pipe is too large, the nitrogen pushes open the elastic film, so that the elastic film breaks through the restriction of the spring steel sheet, and then the nitrogen enters the heat-conducting box to generate bubbles. The molten phase change layer is affected by the disturbance of the bubbles and accelerates the flow, effectively improving the heat exchange effect between the phase change layer and the heat-conducting box close to the material tank. When the pressure in the heat-conducting box is greater than that in the air pipe, the nitrogen enters the air pipe from the one-way air valve. At the same time, due to the continuous pressing operation, the change of ambient temperature and other factors, the slot wall temperature of the material tank is always dynamically changing within the specified range, that is, the temperature in the heat-conducting box and the air pipe is always in dynamic change, and the pressure difference between the air pipe and the heat-conducting box is also in dynamic change; 3. When the magnetic core is pressed and guided away from the mold plate through the guide plate, the suction tube absorbs the magnetic powder remaining on the surface of the magnetic core to reduce the temperature of the magnetic core. At the same time, the excess magnetic powder in the temporary storage box is sucked back through the suction tube and finally merged into the return pipe together with the magnetic powder sucked by the suction tube, so as to reduce the waste of magnetic powder and reduce the accident rate of personnel being scalded. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application; Figure 2 is along Figure 1 Schematic diagram of the cross-sectional structure along the AA line; Figure 3 yes Figure 2 A magnified schematic diagram of part B; Figure 4 yes Figure 2 A magnified schematic diagram of part C; Figure 5 yes Figure 1 The enlarged schematic diagram of the D part; Figure 6 This application is mainly used to show the structural schematic diagram of the loading frame, temporary storage box, shovel plate, dividing bar, rotating shaft, mold plate and material trough.

[0027] Figure numerals: 1. body; 11. rotating shaft; 12. mold plate; 121. material trough; 122. containing groove; 13. upper punch; 14. lower punch; 15. guide plate; 16. feeding barrel; 17. feeding pipe; 2. mounting frame; 21. limit frame; 22. conveyor belt; 23. coil; 24. guide rod; 25. brush; 3. temperature control component; 31. heat conduction box; 32. phase change layer; 33. air pipe; 34. one-way air valve; 35. elastic membrane; 36. spring steel sheet; 41. loading frame; 42. temporary storage box; 43. shovel plate; 44. partition strip; 5. suction component; 51. return pipe; 52. suction pipe; 53. suction pipe; 6. filter plate; 7. net; 8. silicon steel sheet. DETAILED DESCRIPTION

[0028] The following is combined with Figure 1-6 This application is described in further detail.

[0029] The present application embodiment discloses a constant temperature pressing and molding device for a pressed powder magnetic core. Figure 1 , Figure 2 and Figure 3 The constant temperature pressing and molding equipment for pressed powder magnetic core comprises a machine body 1, a rotating shaft 11 rotatably arranged on the machine body 1, a mold plate 12 fixedly connected to the rotating shaft 11, an upper punch 13 lifted and lowered by the rotating shaft 11 above the mold plate 12, a lower punch 14 lifted and lowered by the rotating shaft 11 below the mold plate 12, a guide plate 15 fixedly connected to the machine body 1, a feed barrel 16 fixedly connected to the machine body 1 and a feed pipe 17 connected to the feed barrel 16, a plurality of material troughs 121 adapted to the upper punch 13 and the lower punch 14 are provided on the mold plate 12, a mounting frame 2 is fixedly connected to the machine body 1 outside the mold plate 12, a limit frame 21 adapted to the curvature of the mold plate 12 is fixedly connected to the mounting frame 2, a conveyor belt 22 is arranged in the limit frame 21, a plurality of coils 23 are arranged on the conveyor belt 22, the input end and the output end of the coil 23 are fixedly connected to the conveyor belt 22, and the center of the coil 23 is aligned with the mold plate 1 2 is aligned with the trough 121 of the mold plate 12 and the speeds of the two are equal. A temperature control component 3 for controlling the trough wall temperature of the trough 121 is provided in the mold plate 12; two guide rods 24 are fixedly connected to the mounting frame 2, and brushes 25 are fixedly connected to the input end and the output end of the coil 23. When the conveyor belt 22 drives the coil 23 to move to a position close to the mold plate 12, the two brushes 25 on the coil 23 are respectively pressed against the two guide rods 24, and the mold plate 12 is free of Magnetic stainless steel; a loading frame 41 is fixedly connected to the mounting frame 2 on the side of the feed pipe 17 away from the guide plate 15, the loading frame 41 is fitted with the mold plate 12, a temporary storage box 42 is fixedly connected to the end of the loading frame 41 away from the feed pipe 17, a shovel plate 43 inclined downward is fixedly connected to the top of the temporary storage box 42 close to the end of the feed pipe 17, the shovel plate 43 is also fitted with the mold plate 12, and a suction component 5 for sucking excess magnetic powder in the temporary storage box 42 is provided on the machine body 1.

[0030] The magnetic powder in the feeding barrel 16 falls into the loading frame 41 through the feeding pipe 17. When the material trough 121 on the mold plate 12 moves to the bottom of the loading frame 41, the magnetic powder stored in the feeding pipe 17 and the loading frame 41 falls into the material trough 121, and the coil 23 is also transported by the conveyor belt 22 to the top of the material trough 121 and moves synchronously with the corresponding material trough 121. At the same time, the brush 25 on the coil 23 is tightly attached to the guide rod 24. The two guide rods 24 provide alternating current to the coil 23, so that the coil 23 generates an alternating magnetic field. The magnetic powder vibrates under the effect of the changing magnetic field, so that the magnetic powders are closely attached to each other. At the same time, the magnetic powder is heated due to the eddy current phenomenon. When the coil 23 moves to the point where the brush 25 disengages from the guide rod 24 and contacts the guide rod 24, the coil 23 stops heating the magnetic powder. At this time, the magnetic powder reaches the pressing temperature due to the heating of the coil 23, and a trough is completed. 121 is loaded and the magnetic powder in the material trough 121 is heated. At this time, the magnetic powder in the loading frame 41 conveyed with the mold plate 12 is shoveled into the temporary storage box 42 by the shovel plate 43 and extracted by the suction component 5; as the mold plate 12 continues to rotate, the heated magnetic powder is pressed down by the upper punch 13 to press the magnetic powder into a magnetic core. After the pressing and forming, the upper punch 13 moves up and resets, and the lower punch 14 moves up and pushes out the magnetic core. When the pushed out magnetic core moves to the guide plate 15, the magnetic core moves and unloads under the guidance of the guide plate 15, and then the lower punch 14 moves down and resets. During the pressing process of the magnetic powder by the upper punch 13, the friction between the magnetic powder and the trough wall of the material trough 121 generates a lot of heat. During long-term operation, the temperature control component 3 controls the trough wall temperature of the material trough 121 to avoid the trough wall temperature of the material trough 121 being too high to affect the stability of the pressed magnetic core and the service life of the mold plate 12.

[0031] Reference Figure 2 and Figure 4The mold plate 12 is provided with a plurality of receiving grooves 122 around the groove wall of each material groove 121. The temperature control component 3 includes a heat-conducting box 31 placed in the receiving groove 122 and a phase change layer 32 filled in the heat-conducting box 31. The phase change layer 32 can be a ternary eutectic layer of sodium nitrate, potassium nitrate and sodium nitrite, or can be sebacic acid and its composite material or other phase change materials. The phase change layer 32 of the present application is a ternary eutectic layer of sodium nitrate, potassium nitrate and sodium nitrite. The temperature control assembly 3 also includes an air pipe 33 opened in the peripheral wall of the heat-conducting box 31, a one-way air valve 34 arranged at one end of the air pipe 33, an elastic membrane 35 arranged at the other end of the air pipe 33, and a control component for controlling the deflation of the elastic membrane 35. The one-way air valve 34 only allows gas to flow from the heat-conducting box 31 into the air pipe 33, and the one-way air valve 34 is located at the top of the heat-conducting box 31. Nitrogen or inert gas is injected into the air pipe 33. In the present application, the gas in the air pipe 33 is nitrogen. A heat-conducting rod is also fixed to the air pipe 33 at the bottom. The bottom of the heat-conducting box 31 is thick high-strength steel. The heat-conducting box 31 is connected to the mold plate 12 by countersunk bolts to reduce the influence of the heat-conducting box 31 on the strength of the mold plate 12, and at the same time facilitate maintenance of the heat-conducting box 31.

[0032] The melting point of the phase change layer 32 is adjusted by adjusting the ratio of the three salts of sodium nitrate, potassium nitrate and sodium nitrite in the heat-conducting box 31, thereby adapting to the temperature range corresponding to different types of magnetic cores. During the magnetic powder pressing process, the temperature of the slot wall of the material slot 121 is transferred to the heat-conducting box 31, and then transferred to the phase change layer 32 by the heat-conducting box 31. When the temperature of the slot wall of the material slot 121 is high, the phase change layer 32 is heated and melted and absorbs heat, so that the slot wall of the material slot 121 is always in a constant temperature state. When the air pipe 33 is continuously heated, the nitrogen in the air pipe 33 expands and squeezes the elastic membrane 35. When the pressure in the air pipe 33 is too high, the nitrogen pushes open the elastic membrane 35, so that the elastic membrane 35 breaks through the pressing effect of the control component, and then the nitrogen enters the heat conduction box 31 to generate bubbles. The molten phase change layer 32 is affected by the disturbance of the bubbles and accelerates the flow, thereby improving the heat exchange effect between the phase change layer 32 and the side of the heat conduction box 31 close to the material tank 121. When the pressure in the heat conduction box 31 is greater than that in the air pipe 33, the nitrogen enters the air pipe 33 from the one-way valve 34. At the same time, due to the continuous pressing operation, the change of ambient temperature, the melting of the phase change layer 32 and other factors, the temperature of the tank wall of the material tank 121 is always dynamically changing within a specified range, that is, the temperature in the heat conduction box 31 and the air pipe 33 is always in a dynamic change, and the pressure difference between the air pipe 33 and the heat conduction box 31 is also in a dynamic change.

[0033] Reference Figure 4The control part is a spring steel sheet 36 with one end fixed to the inner bottom wall of the heat-conducting box 31 or a heat-resistant elastic rope with both ends fixed to the inner bottom wall of the heat-conducting box 31. The elastic membrane 35 of the present application is divided into an adhesive portion and a fitting portion. The adhesive portion of the elastic membrane 35 is seamlessly bonded to the inner wall of the heat-conducting box 31, and the fitting portion of the elastic membrane 35 fits the inner wall of the heat-conducting box 31, and the spring steel sheet 36 presses the fitting portion of the elastic membrane 35. The air inlet end of the one-way air valve 34 and the end of the air pipe 33 close to the elastic membrane 35 are both fixed with a filter plate 6 that only allows gas to pass.

[0034] The elastic membrane 35 bulges under the influence of air pressure, but the spring steel sheet 36 presses the fitting part of the elastic membrane 35, causing the pressure in the air pipe 33 to become higher and higher, until the pressure in the air pipe 33 is greater than the restriction of the spring steel sheet 36 on the elastic membrane 35. At this time, a gap appears between the fitting part of the elastic membrane 35 and the inner wall of the heat-conducting box 31, and nitrogen enters the phase change layer 32 through the gap; at the same time, as nitrogen is discharged from the air pipe 33, the spring steel sheet 36 presses the elastic membrane 35 again, completing an exhaust process. The filter plate 6 prevents the molten phase change layer 32 in the heat-conducting box 31 from entering the air pipe 33 through the one-way air valve 34 and the elastic membrane 35 end of the air pipe 33, thereby effectively preventing the phase change material from blocking the air pipe 33 and the one-way air valve 34.

[0035] Reference Figure 2 and Figure 5 The suction assembly 5 includes a return pipe 51 connected to the supply barrel 16, a suction pipe 52 connected to the return pipe 51 and a suction pipe 53 connected to the suction pipe 52. The end of the suction pipe 52 close to the return pipe 51 is in a closed shape, and the end of the return pipe 51 close to the suction pipe 52 is also in a closed shape. The connection between the suction pipe 53 and the suction pipe 52 is located at the closed end of the suction pipe 53. The suction pipe 53 is connected to the side wall of the temporary storage box 42. The suction pipe 52 is connected to an external air source. The end of the return pipe 51 close to the supply barrel 16 is connected to a bag net 7 with a bottom opening to reduce the speed of the magnetic powder sprayed out of the return pipe 51.

[0036] When the suction tube 52 inhales air, when the airflow moves to the closing part of the suction tube 52, the flow rate of the airflow increases and the pressure decreases due to the reduction of the aperture, that is, the pressure at one end of the suction tube 53 close to the suction tube 52 is less than that at one end of the suction tube 53 close to the temporary storage box 42. At this time, the magnetic powder in the temporary storage box 42 is sucked by the suction tube 53, and at the same time, the suction tube 52 also sucks the magnetic powder remaining on the surface of the pressed magnetic core, so that the magnetic powder on the temporary storage box 42 and the magnetic core are sucked to the return tube 51, and finally input into the feed barrel 16 by the return tube 51 to avoid the waste of magnetic powder. After the magnetic core is formed, the suction tube 52 also performs a certain cooling treatment on the magnetic core to reduce the accident of scalding of the staff.

[0037] Reference Figure 3A plastic screw is fixedly connected to one end of the coil 23 near the middle height of the conveyor belt 22, and a silicon steel sheet 8 is sleeved on the plastic screw. Plastic nuts are threadedly connected to both ends of the plastic screw and the silicon steel sheet 8. The silicon steel sheet 8 effectively enhances the concentration and guidance of the magnetic field generated by the coil 23, that is, due to factors such as the global transmission of the magnetic field, the magnetic field at one end of the coil 23 away from the silicon steel sheet 8 also changes, which helps to guide the alternating magnetic field to the material trough 121, thereby reducing the leakage of the magnetic field and enhancing the movement efficiency and heating speed of the magnetic powder. When the type of magnetic powder or the current of the coil 23 changes, the staff can also adjust the height of the silicon steel sheet 8 by adjusting the plastic nut.

[0038] Reference Figure 5 , a plurality of partition bars 44 whose height is lower than that of the loading frame 41 are fixedly connected in the loading frame 41, and the partition bars 44 are arc-shaped, and the middle of the partition bars 44 is located on the moving path of the material trough 121. When the mold plate 12 rotates, the magnetic powder located in the loading frame 41 and on the mold plate 12 is scraped into the material trough 121 by the partition bars 44, and the alternating magnetic field of the coil 23 produces a slight vibration on the magnetic powder, so that the magnetic powder in the material trough 121 is vibrated and the surface is concave, and then it is filled up by the next partition bar 44, thereby improving the final feeding effect of the material trough 121.

[0039] The implementation principle of the constant temperature pressing and molding equipment of a powder core in the embodiment of the present application is as follows: the magnetic powder in the feeding barrel 16 falls into the loading frame 41 through the feeding pipe 17, and when the material trough 121 on the mold plate 12 moves to the bottom of the loading frame 41, the magnetic powder stored in the feeding pipe 17 and the loading frame 41 falls into the material trough 121, and the coil 23 is also transported by the conveyor belt 22 to the top of the material trough 121 and moves synchronously with the corresponding material trough 121, and at the same time, the brush 25 on the coil 23 is tightly attached to the guide rod 24, and the two guide rods 24 provide alternating current to the coil 23, thereby causing the coil 23 to generate an alternating magnetic field, and the magnetic powder vibrates under the effect of the changing magnetic field, so that the magnetic powders are closely attached to each other, and at the same time, the magnetic powder is heated due to the eddy current phenomenon; The die plate 12 continues to rotate, and the heated magnetic powder is pressed downward by the upper punch 13 to be pressed into a magnetic core. During the pressing process of the magnetic powder, the temperature of the slot wall of the material slot 121 is transferred to the heat-conducting box 31, and then transferred to the phase change layer 32 by the heat-conducting box 31. When the slot wall temperature of the material slot 121 is high, the phase change layer 32 is heated and melts and absorbs heat. When the air pipe 33 is continuously heated, the nitrogen in the air pipe 33 expands and squeezes the elastic membrane 35. When the pressure in the air pipe 33 is too high, the nitrogen pushes open the elastic membrane 35, so that the elastic membrane 35 breaks through the restriction of the spring steel sheet 36, and then the nitrogen enters the heat-conducting box 31. Bubbles are generated inside the material tank 121, and the molten phase change layer 32 is affected by the disturbance of the bubbles and flows faster, thereby improving the heat exchange effect between the phase change layer 32 and the side of the heat conduction box 31 close to the material tank 121. When the pressure inside the heat conduction box 31 is greater than that in the air pipe 33, nitrogen enters the air pipe 33 from the one-way air valve 34. At the same time, due to the influence of factors such as the continuous pressing operation, the temperature of the tank wall of the material tank 121 is always dynamically changing within the specified range, that is, the temperature inside the heat conduction box 31 and the air pipe 33 is always in a dynamic change, and the pressure difference between the air pipe 33 and the heat conduction box 31 is also in a dynamic change; After the magnetic core is pressed and formed, the upper punch 13 moves upward to reset, and the lower punch 14 moves upward to push out the magnetic core. When the pushed-out magnetic core moves to the guide plate 15, the magnetic core moves to unload under the guidance of the guide plate 15, and then the lower punch 14 moves downward to reset, completing the pressing and forming process of a magnetic core. When the magnetic core is pressed and guided away from the mold plate 12 through the guide plate 15, the suction tube 52 absorbs the magnetic powder remaining on the surface of the magnetic core to reduce the temperature of the magnetic core. At the same time, the excess magnetic powder in the temporary storage box 42 is sucked back through the suction tube 52 and finally merged into the return tube 51 together with the magnetic powder sucked by the suction tube 52 to reduce the waste of magnetic powder.

[0040] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A constant temperature pressing and molding device for a pressed powder magnetic core, comprising a machine body (1), a rotating shaft (11) rotatably arranged on the machine body (1), a mold plate (12) fixedly connected to the rotating shaft (11), an upper punch (13) arranged on the rotating shaft (11) to be lifted above the mold plate (12), a lower punch (14) arranged on the rotating shaft (11) to be lifted below the mold plate (12), a guide plate (15) fixedly connected to the machine body (1), a feed barrel (16) fixedly connected to the machine body (1) and a feed pipe (17) connected to the feed barrel (16), wherein the mold plate (12) is provided with a plurality of material troughs (121) adapted to the upper punch (13) and the lower punch (14), and characterized in that: The machine body (1) is fixedly connected to a mounting frame (2) outside the mold plate (12); a limit frame (21) adapted to the curvature of the mold plate (12) is fixedly connected to the mounting frame (2); a conveyor belt (22) is arranged inside the limit frame (21); a plurality of coils (23) are arranged on the conveyor belt (22); the input end and the output end of the coil (23) are both fixedly connected to the conveyor belt (22); the center of the coil (23) is aligned with the material trough (121) of the mold plate (12) and the speeds of the two are equal; a temperature control component (3) for controlling the trough wall temperature of the material trough (121) is arranged inside the mold plate (12); Two guide rods (24) are fixedly connected to the mounting frame (2), brushes (25) are fixedly connected to the input end and the output end of the coil (23), and when the conveyor belt (22) drives the coil (23) to move to a position close to the mold plate (12), the two brushes (25) on the coil (23) are respectively pressed against the two guide rods (24), and the mold plate (12) is made of non-magnetic stainless steel; The mounting frame (2) is fixedly connected to a loading frame (41) on a side of the feeding pipe (17) away from the guide plate (15), and the loading frame (41) is fitted with the mold plate (12). The loading frame (41) is fixedly connected to an end of the feeding frame (41) away from the feeding pipe (17) with a temporary storage box (42). The top of the temporary storage box (42) close to one end of the feeding pipe (17) is fixedly connected to a shovel plate (43) inclined downward, and the shovel plate (43) is also fitted with the mold plate (12). The machine body (1) is provided with a suction component (5) for sucking excess magnetic powder in the temporary storage box (42).

2. The constant temperature pressing and molding equipment for powder magnetic cores according to claim 1, characterized in that: The mold plate (12) is provided with a plurality of receiving grooves (122) around the groove wall of each of the material grooves (121); the temperature control component (3) comprises a heat-conducting box (31) placed in the receiving groove (122) and a phase change layer (32) filled in the heat-conducting box (31); the phase change layer (32) is a ternary eutectic layer of sodium nitrate, potassium nitrate and sodium nitrite.

3. The constant temperature pressing and molding equipment for powder magnetic cores according to claim 2, characterized in that: The temperature control assembly (3) further comprises an air pipe (33) provided in the peripheral wall of the heat-conducting box (31), a one-way air valve (34) arranged at one end of the air pipe (33), an elastic membrane (35) arranged at the other end of the air pipe (33), and a control component for controlling the deflation of the elastic membrane (35), wherein the one-way air valve (34) only allows gas to flow from the heat-conducting box (31) into the air pipe (33), the air pipe (33) is filled with nitrogen, and the one-way air valve (34) is located at the top end of the heat-conducting box (31).

4. The constant temperature pressing and molding equipment for pressed powder magnetic cores according to claim 3, characterized in that: The control component is a spring steel sheet (36) with one end fixed to the inner bottom wall of the heat-conducting box (31); the elastic membrane (35) is divided into an adhesive portion and a fitting portion; the adhesive portion of the elastic membrane (35) is seamlessly bonded to the inner wall of the heat-conducting box (31); the fitting portion of the elastic membrane (35) is fitted to the inner wall of the heat-conducting box (31); and the spring steel sheet (36) presses the fitting portion of the elastic membrane (35).

5. The constant temperature pressing and molding equipment for pressed powder magnetic cores according to claim 4, characterized in that: The air inlet end of the one-way air valve (34) and one end of the air pipe (33) close to the elastic membrane (35) are both fixedly connected with a filter plate (6) that only allows air to pass through.

6. The constant temperature pressing and molding equipment for powder magnetic cores according to claim 1, characterized in that: The suction assembly (5) comprises a return pipe (51) connected to the supply barrel (16), a suction pipe (52) connected to the return pipe (51), and a suction pipe (53) connected to the suction pipe (52); one end of the suction pipe (52) close to the return pipe (51) is closed; a connection between the suction pipe (53) and the suction pipe (52) is located at the closed end of the suction pipe (53); the suction pipe (53) is connected to a side wall of the temporary storage box (42); and the suction pipe (52) is externally connected to an air source.

7. The constant temperature pressing and molding equipment for powder magnetic cores according to claim 6, characterized in that: One end of the return pipe (51) close to the supply barrel (16) is connected to a net (7) with an opening at the bottom.

8. The constant temperature pressing and molding equipment for pressed powder magnetic cores according to claim 1, characterized in that: A silicon steel sheet (8) is provided in a lifting manner at one end of the coil (23) close to the middle of the conveyor belt (22).

9. The constant temperature pressing and molding equipment for powder magnetic cores according to claim 1, characterized in that: A plurality of partition bars (44) whose height is lower than that of the loading frame (41) are fixedly connected inside the loading frame (41); the partition bars (44) are arc-shaped, and the middle of the partition bars (44) is located on the movement path of the material trough (121).

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