Metal powder injection molding apparatus for gear machining and method thereof

Abstract

The application discloses a metal powder injection molding device for gear machining and a method thereof, and belongs to the technical field of metal powder machining equipment, and comprises a machine body, an injection unit, a mold clamping unit, a mold assembly and a power driving system. The mold clamping unit comprises a fixed mold plate, the fixed mold plate is provided with a receiving switching mechanism and a cleaning mechanism on one side, the receiving switching mechanism comprises a switching disc, two mounting holes and an annular mounting groove outside the periphery of each mounting hole are arranged on the switching disc, an electromagnetic receiving assembly is arranged in each mounting groove, and the electromagnetic receiving assembly comprises an annular electromagnet and a receiving sleeve. Through the application, the receiving sleeve can be automatically switched, cleaning and production can be carried out in parallel, the equipment downtime is reduced, the production efficiency is improved, the risk of scalding caused by manual cleaning is reduced, the mechanical scraping and cleaning are uniform and comprehensive, the surface damage of the receiving sleeve can be reduced, the service life of the receiving sleeve is prolonged, and the cleaning operation does not interfere with normal production operation.

Description

Technical Field

[0001] This invention belongs to the technical field of metal powder processing equipment, and more specifically relates to a metal powder injection molding device and method for gear processing. Background Technology

[0002] The metal powder injection molding device for gear processing is a specialized piece of equipment adapted to the production of micro precision gears, combining the principles of powder metallurgy and injection molding. Relying on a wear-resistant screw, a precise temperature-controlled injection unit, and a gear-specific cavity mold, it mixes and feeds metal powder and binder, melts and pressurizes the mixture, and injects it into the gear mold with reserved sintering shrinkage. After cooling and demolding, a gear blank is obtained. With the help of subsequent degreasing and sintering equipment, it can batch-produce gear blanks with complex tooth shapes, reduce the amount of subsequent cutting processing, and improve the dimensional consistency and material utilization of micro gears.

[0003] In the metal powder injection molding process, residual feed material overflowing from the injection end often accumulates at the nozzle orifice of the fixed mold plate. There are two main reasons for this phenomenon: First, there is a misalignment between the injection nozzle and the mold sprue sleeve, or the sealing surface is worn and the sealing performance decreases. During high-pressure injection, the molten feed material overflows from the gap between the parts and accumulates in the orifice area. Second, the residual pressure at the nozzle tip is too high after injection, and a small amount of molten feed material drips and gradually forms residue at the orifice.

[0004] Currently, these residues are mainly cleaned manually by scraping them off with tools after the machine is stopped. However, due to the high temperature of the nozzle and surrounding mold area, there is a certain risk of burns during the operation. If these residues are not cleaned in time, they will have adverse effects. On the one hand, the accumulated residual material is easily detached after being vibrated and impacted by the injection action. It enters the mold cavity along with the subsequent molten feed and mixes into the green body, which can easily cause problems such as hard spots and uneven density distribution inside the green body, reducing the stability of the product molding quality. On the other hand, the residual material gradually hardens after being repeatedly heated in a high-temperature environment. It will be stuck between the contact surface of the nozzle and the sprue bushing. Under the action of injection clamping force, it can easily damage the nozzle and shorten the normal service life of the nozzle. Summary of the Invention

[0005] This invention addresses the problem of overly simplistic solutions in existing technologies by providing a significantly different approach. Belonging to the technical field of metal powder processing equipment, this invention primarily provides a metal powder injection molding apparatus and method for gear processing. It addresses the technical problem mentioned in the background section where accumulated material in the nozzle orifice of the fixed mold plate in current metal powder injection molding apparatuses, if not cleaned promptly, easily enters the mold cavity along with subsequent molten feed and mixes with the green blank, reducing product quality.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: A metal powder injection molding apparatus for gear processing includes a body, on which an injection unit, a mold clamping unit, a mold assembly, and a power drive system are mounted. The mold clamping unit includes a fixed mold platen for positioning a fixed mold in the mold assembly. The fixed mold platen has a nozzle through-hole. A receiving and switching mechanism and a clearing mechanism are located on the side of the fixed mold platen near the injection unit. The receiving and switching mechanism includes a switching disc with two mounting holes and an annular mounting groove on the outer edge of each mounting hole. The mounting holes have the same diameter as the nozzle through-hole. An electromagnetic receiving assembly is disposed within each mounting groove. The electromagnetic receiving assembly includes an annular electromagnet and a receiving sleeve. The annular electromagnet is embedded in an annular mounting groove, and the receiving sleeve is located in the nozzle through hole. The annular electromagnet can be energized to pull and attract the receiving sleeve. The end face of the receiving sleeve in the lower electromagnetic receiving assembly near the mold assembly is flush with the back of the fixed template, and the end face of the receiving sleeve in the upper electromagnetic receiving assembly near the mold assembly is flush with the front of the fixed template. The cleaning mechanism includes a cover, and two interface positions on the cover are rotatably connected to a rotating shaft and a composite shaft, respectively. A gear is provided on the rotating shaft, and a toothed part is bonded to the gear. The toothed part is located at the outer edge of the switching disk.

[0007] Preferably, a support shaft is bolted to the center of the switching disk, the support shaft is rotatably connected to the interface of the fixed template, and a bearing is provided in the gap between the support shaft and the interface of the fixed template.

[0008] Preferably, multiple springs are equidistantly arranged between the annular electromagnet and the receiving sleeve, and multiple limiting grooves are equidistantly arranged around the outer shell of the annular electromagnet, with the springs sleeved on the corresponding limiting grooves. Each limiting groove is movably connected to a limiting head, which is installed on the receiving sleeve by bolts.

[0009] Preferably, limiting bolts are movably connected in the circular holes on both sides of the receiving sleeve, and the limiting bolts are engaged with the threaded holes on the corresponding annular mounting grooves.

[0010] Preferably, the composite shaft includes a connecting part, a receiving part, and a plug-in part. The receiving part is provided with a plurality of bending cleaning plates arranged at equal intervals around it. The bending cleaning plates include an inner wall cleaning part and an end face cleaning part.

[0011] Preferably, a sliding opening is provided on the lower side of the cover, and a collection groove is movably connected inside the sliding opening.

[0012] Preferably, a first motor and a drive assembly are bolted to the cover, and the output end of the first motor is connected to one end of the rotating shaft.

[0013] Preferably, the drive assembly includes a support frame, which is bolted to the outer wall of the housing. The support frame has two limit rods that are parallel to each other. A sliding plate is provided on both limit rods. A second motor is bolted to the sliding plate. The output end of the second motor is connected to the connection part of the composite shaft. A cylinder is bolted to the support frame. A push frame is provided at the output end of the cylinder. The push frame is bolted to the upper side of the housing of the second motor.

[0014] Preferably, the upper side of the fixed template is provided with an installation port, and a purging mechanism is provided in the installation port. The purging mechanism includes a cavity and an end cap, and the cavity and the end cap are connected by bolts. A purging cover is rotatably connected to an interface on the side wall of the cavity. A shaft seal is provided at the gap between the purging cover and the interface on the side wall of the cavity. A plug-in groove is provided at the center of the purging cover. The plug-in groove fits with the plug-in part. Multiple air outlets are provided equidistantly around the plug-in groove. An air inlet connector is provided on the upper side of the end cap.

[0015] A method for metal powder injection molding apparatus for gear processing, comprising the following specific steps: S1 Separation Preparation: When there is residual molten metal powder and binder mixture on the inner wall and end face of the receiving sleeve, the annular electromagnet in the lower electromagnetic receiving assembly is de-energized, the traction force of the annular electromagnet on the receiving sleeve disappears, the compressed return spring is restored to its original shape, and a force is applied to the receiving sleeve in the direction of the injection unit, causing the receiving sleeve to slide along the limit bolt and abut against the head of the limit bolt. The end of the receiving sleeve near the mold assembly separates from the nozzle through hole of the fixed mold plate. S2 Rotation Switching: The first motor drives the gear to rotate through the shaft. The gear meshes with the gear part on the switching disk. The switching disk rotates around the support shaft as the fulcrum, and the two electromagnetic receiving components are swapped. The receiving sleeve with residual material in the lower electromagnetic receiving component is moved to the upper component, and the receiving sleeve without residual material in the upper electromagnetic receiving component is moved to the lower component. S3 Reassembly: The annular electromagnet in the lower electromagnetic receiving assembly is energized, and a traction force is generated on the receiving sleeve without residual material, which is attracted. Then the receiving sleeve moves closer to the mold assembly along the limiting bolt. The spring is compressed, and then the limiting groove and the limiting head are fully inserted together. At the same time, the end face of the receiving sleeve close to the mold assembly is flush with the back of the fixed template, completing the assembly. S4 Scraping and Cleaning: The cylinder pulls the second motor along the limit rod to the side of the receiving sleeve with residual material in the upper electromagnetic receiving assembly via the push frame, so that the plug part on the composite shaft is inserted into the plug slot of the blow cover. Then the second motor drives the composite shaft to rotate, and the bending cleaning blade on the composite shaft rotates to scrape. The inner wall cleaning part and the end face cleaning part on the bending cleaning blade clean the residue on the inner wall and end face of the receiving sleeve, respectively. S5 Purge Collection: While the composite shaft rotates, the purge cover on the cavity rotates, and the high-pressure gas inside the cavity is ejected from the air outlet on the purge cover to purge the inner wall of the receiving sleeve. The material removed is blown to one side of the inner wall of the cover and then falls down the inner wall of the cover into the collection tank for collection.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention achieves automatic separation of the receiving sleeve with residual material from the nozzle through hole through the set receiving switching mechanism. Then, the switching disk rotates around the support shaft through gear meshing to achieve the swapping of the two electromagnetic receiving components at the upper and lower work positions. The clean receiving sleeve is pushed back to the nozzle through hole position and the positioning assembly is completed. Compared with the traditional manual disassembly, cleaning and reassembly, the present application can make the residual material cleaning operation and injection molding production run in parallel. There is no need to stop the line for a long time due to the cleaning process, which effectively shortens the equipment standby time and improves the overall efficiency of the equipment. For the mass production of precision parts such as gears, it can reduce the fluctuation of process parameters caused by start-up and shutdown, which is conducive to maintaining the stability of the green blank forming quality. Meanwhile, the entire process does not require operators to have close contact with the high-temperature template and nozzle areas, which can reduce the risk of burns from manual operation.

[0017] (2) The present invention realizes the scraping and cleaning operation of the receiving sleeve with residual material after switching to the upper cleaning station through the cleaning mechanism. The bending cleaning plate is divided into an inner wall cleaning part and an end face cleaning part, which can simultaneously adapt to the inner circumferential surface and the end plane of the receiving sleeve. The residual material in the two areas can be scraped off in one feed rotation. Compared with the manual hand tool scraping point by point, it can effectively scrape off the molten and semi-solid feeding residues attached to the surface of the receiving sleeve, reduce cleaning dead corners, and reduce the risk of scratches on the inner surface of the receiving sleeve caused by uneven force during manual cleaning. It is beneficial to maintain the flatness of the mating surface of the receiving sleeve and extend its service life. Meanwhile, the cleaning process operates independently of the production station, and the scraping operation will not interfere with the injection operation that is underway below. While ensuring the cleaning effect, the impact of the cleaning process on production efficiency is further reduced.

[0018] (3) The present invention, through the blowing mechanism, realizes that during the simultaneous scraping operation, the rotational power of the composite shaft is synchronously transmitted to the blowing cover by the insertion of the insertion part and the insertion slot, so that the high-pressure gas can rotate together with the blowing cover to form a rotating blowing airflow covering the inner wall of the receiving sleeve. The rotating airflow can sweep the entire inner wall of the receiving sleeve in 360 degrees, which can more fully remove the scraped fine debris and metal powder, reduce the residue of debris in the fine parts of the inner wall, and further improve the cleanliness of the receiving sleeve. Meanwhile, the hood can effectively contain the swept-out residue, preventing metal powder-containing waste from scattering and splashing everywhere. Most of the fallen residue will fall into the collection tank for centralized collection, which is conducive to the subsequent recycling of feeding residue, reducing material loss and the workload of daily cleaning and maintenance.

[0019] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the front structure of the template of the present invention; Figure 3 This is a schematic diagram of the back structure of the template of the present invention; Figure 4 This is an exploded view of the structure on the template of the present invention; Figure 5 This is a schematic diagram showing the connection between the receiving and switching mechanism and the fixed template of the present invention; Figure 6 This is an exploded view of the receiving and switching mechanism of the present invention; Figure 7 This is a schematic diagram of the switching disk of the present invention; Figure 8 This is a schematic diagram of the two electromagnetic receiving components of the present invention (the upper part is not energized and has no traction force, while the lower part is energized and has traction force). Figure 9 This is an exploded view of the electromagnetic receiving component of the present invention; Figure 10 This is an exploded view of the cleaning mechanism of the present invention; Figure 11 This is a schematic diagram of the cover of the present invention; Figure 12 This is a schematic diagram of the composite shaft of the present invention; Figure 13 This is a schematic diagram of the driving component of the present invention; Figure 14 This is a schematic diagram of the purging mechanism of the present invention; Figure 15This is an exploded view of the purging mechanism of the present invention.

[0021] In the diagram: 1. Machine body; 2. Injection unit; 3. Mold clamping unit; 31. Fixed mold plate; 311. Bearing; 312. Nozzle through hole; 313. Mounting port; 4. Mold assembly; 5. Power drive system; 6. Receiving and switching mechanism; 61. Switching disc; 611. Mounting hole; 612. Annular mounting groove; 613. Gear part; 62. Support shaft; 63. Electromagnetic receiving assembly; 631. Annular electromagnet; 632. Receiving sleeve; 633. Limiting groove; 634. Spring; 635. Limiting head; 636. Limiting bolt; 7. Clearing mechanism; 71. Cover; 711. Slide; 72. 73. Shaft; 74. Gear; 75. Composite shaft; 76. Connecting part; 77. Receiving part; 78. Bending cleaning plate; 79. Inner wall cleaning part; 70. End face cleaning part; 71. Insertion part; 72. Collection groove; 73. First motor; 74. Drive assembly; 75. Support frame; 76. Limiting rod; 777. Sliding plate; 778. Second motor; 779. Cylinder; 770. Pushing frame; 81. Blowing mechanism; 82. Cavity; 83. Blowing cover; 84. Insertion groove; 85. Air outlet; 86. End cover; 871. Air inlet connector; 88. Shaft seal. Detailed Implementation

[0022] To facilitate understanding of the present invention, a more comprehensive description of the present invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the present invention. However, the present invention can be implemented in different forms and is not limited to the embodiments described in the text. Rather, these embodiments are provided to make the disclosure of the present invention more thorough and complete.

[0023] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly associated with those skilled in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] For the implementation examples, please refer to the appendix. Figure 1 - Appendix Figure 15As shown, a metal powder injection molding device for gear processing includes a body 1. The body 1 is equipped with an injection unit 2, a mold-locking unit 3, a mold assembly 4, and a power drive system 5. The mold-locking unit 3 includes a fixed template 31 for positioning the fixed mold in the mold assembly 4. The fixed template 31 has a nozzle through-hole 312. A receiving and switching mechanism 6 and a clearing mechanism 7 are provided on the side of the fixed template 31 near the injection unit 2. The receiving and switching mechanism 6 includes a switching disk 61 with two mounting holes 611 and an annular mounting groove 612 on the outer edge of each mounting hole 611. The mounting holes 611 have the same diameter as the nozzle through-hole 312. Each mounting groove contains an electromagnetic receiving assembly 63, which includes an annular electromagnet 631 and a receiving... The sleeve 632 and the annular electromagnet 631 are embedded in the annular mounting groove 612. The receiving sleeve 632 is located in the nozzle through hole 312. The annular electromagnet 631 can be energized to pull and attract the receiving sleeve 632. The end face of the receiving sleeve 632 in the lower electromagnetic receiving assembly 63 near the mold assembly 4 is flush with the back of the fixed template 31. The end face of the receiving sleeve 632 in the upper electromagnetic receiving assembly 63 near the mold assembly 4 is flush with the front of the fixed template 31. The cleaning mechanism 7 includes a cover 71. The two interface positions on the cover 71 are respectively rotatably connected to a rotating shaft 72 and a composite shaft 74. The rotating shaft 72 is provided with a gear 73. The gear 73 is bonded to a toothed part 613. The toothed part 613 is located at the outer edge of the switching disk 61. The composite shaft 74 and the receiving sleeve 632 located above share a central axis.

[0026] The specific operation is as follows: after the nozzle of the injection unit 2 is removed from the receiving sleeve 632, when there is molten metal powder and binder mixed feeding residue on the inner wall and end face of the receiving sleeve 632, the annular electromagnet 631 in the lower electromagnetic receiving assembly 63 is de-energized, the traction force of the annular electromagnet 631 on the receiving sleeve 632 disappears, the compressed return spring 634 is restored to its original shape, and a force is applied to the receiving sleeve 632 in the direction of the injection unit 2, so that the receiving sleeve 632 slides along the limiting bolt 636 and abuts against the head of the limiting bolt 636, and the end of the receiving sleeve 632 near the mold assembly 4 separates from the nozzle through hole 312 of the fixed platen 31; Then, the first motor 76 drives the gear 73 to rotate through the rotating shaft 72. The gear 73 meshes with the gear part 613 on the switching disk 61. Subsequently, the switching disk 61 rotates around the support shaft 62 as the fulcrum, and the two electromagnetic receiving components 63 are swapped. The receiving sleeve 632, which originally had residual material in the lower electromagnetic receiving component 63, is moved to the upper part, and the receiving sleeve 632, which originally had no residual material in the upper electromagnetic receiving component 63, is moved to the lower part. The annular electromagnet 631 in the electromagnetic receiving component 63 that has been swapped to the lower part is energized, and a traction force is generated on the receiving sleeve 632, which has no residual material, to attract it. Subsequently, the receiving sleeve 632 moves closer to the mold component 4 along the limiting bolt 636. The spring 634 is compressed, and then the limiting groove 633 and the limiting head 635 are completely inserted together. At the same time, the end face of the receiving sleeve 632 on the side close to the mold component 4 is flush with the back of the fixed template 31, and the assembly is completed. Subsequently, cylinder 775 pulls second motor 774 along limit rod 772 via push frame 776 to move towards the receiving sleeve 632 with residual material in the upper electromagnetic receiving assembly 63, causing the insertion part 744 on composite shaft 74 to insert into insertion slot 821 of purge cover 82. Then, second motor 774 drives composite shaft 74 to rotate, and bending cleaning blade 743 on composite shaft 74 rotates to scrape away the inner wall of the bending cleaning blade 743. Section 7431 and end face cleaning section 7432 clean the residue on the inner wall and end face of the receiving sleeve 632, respectively. While the composite shaft 74 rotates, the purge cover 82 on the cavity 81 rotates, and the high pressure gas in the cavity 81 is ejected from the air outlet 822 on the purge cover 82 to rotate and purge the inner wall of the receiving sleeve 632, blowing the removed material to one side of the inner wall of the cover 71, and then falling down the inner wall of the cover 71 into the collection tank 75 for collection.

[0027] Please refer to the appendix carefully. Figure 6 - Appendix Figure 9As shown, a support shaft 62 is bolted to the center of the switching disk 61. The support shaft 62 is rotatably connected to the interface of the fixed template 31. A bearing 311 is installed in the gap between the support shaft 62 and the interface of the fixed template 31. The bearing 311 improves the stability of the support shaft 62 at the interface. Multiple springs 634 are equidistantly arranged between the annular electromagnet 631 and the receiving sleeve 632. Multiple limiting grooves 633 are equidistantly arranged around the outer shell of the annular electromagnet 631, and the springs 634 are sleeved on the corresponding limiting grooves 633. Each limiting groove 633 is movably connected to a limiting head 635, which is bolted to the receiving sleeve 632. By cooperating with the limiting head 635 and the limiting groove 633, the movement range of the receiving sleeve 632 is limited during its movement toward the mold assembly 4, ensuring that the end face of the receiving sleeve 632 near the mold assembly 4 is flush with the back of the fixed template 31. Limiting bolts 636 are movably connected in the circular holes on both sides of the receiving sleeve 632. The limiting bolts 636 engage with the threaded holes on the corresponding annular mounting groove 612. Through the limiting bolts 636, the movement range of the receiving sleeve 632 is limited when it moves toward the injection unit 2. At the maximum movement range, the end face of the receiving sleeve 632 near the mold assembly 4 is in contact with the front of the fixed template 31.

[0028] Please refer to the appendix carefully. Figure 10 - Appendix Figure 15As shown, the composite shaft 74 includes a connecting part 741, a receiving part 742, and an insertion part 744. Multiple bending cleaning blades 743 are equidistantly arranged around the receiving part 742. Each bending cleaning blade 743 includes an inner wall cleaning part 7431 and an end face cleaning part 7432. Through the inner wall cleaning part 7431 and the end face cleaning part 7432, the inner wall of the receiving sleeve 632 and the end face near the injection unit 2 are cleaned (the end face of the receiving sleeve 632 near the mold assembly 4 is in direct contact with the fixed mold of the mold assembly 4, so there is no residual material and no cleaning is required). A sliding opening 711 is provided on the lower side of the cover 71. A collection groove 75 is movably connected within the sliding opening 711, allowing for the centralized collection of most residual material. A first motor 76 and a drive assembly 77 are bolted to the cover 71. The first motor 76... The output end of the drive assembly 77 is connected to one end of the rotating shaft 72. Through the first motor 76, the drive force for the rotation of the rotating shaft 72 is realized. The drive assembly 77 includes a support frame 771. The support frame 771 and the outer wall of the cover 71 are connected by bolts. Two limit rods 772 are provided on the support frame 771. The two limit rods 772 are distributed in parallel. A sliding plate 773 is provided on both limit rods 772. The sliding plate 773 is connected to the second motor 774 by bolts. The output end of the second motor 774 is connected to the connecting part 741 of the composite shaft 74. The support frame 771 is connected to the cylinder 775 by bolts. The output end of the cylinder 775 is provided with a push frame 776. The push frame 776 is connected to the upper side of the housing of the second motor 774 by bolts. Through the drive assembly 77, the drive force for the composite shaft 74 to clean the residual material is realized. The upper side of the fixed template 31 is provided with an installation port 313, and a purging mechanism 8 is provided inside the installation port 313. The purging mechanism 8 includes a cavity 81 and an end cap 83, and the cavity 81 and the end cap 83 are connected by bolts. A purging cover 82 is rotatably connected to the interface on the side wall of the cavity 81. A shaft seal 84 is provided in the gap between the purging cover 82 and the interface on the side wall of the cavity 81. A plug groove 821 is provided at the center of the purging cover 82, and the plug groove 821 fits with the plug part 744. The purging cover 82 can be rotated by the driving force brought by the composite shaft 74. Multiple air outlets 822 are provided equidistantly around the circumference of the plug groove 821. An air inlet connector 831 is provided on the upper side of the end cap 83. The air inlet connector 831 enables the connection to the external high-pressure pipeline so as to introduce high-pressure gas.

[0029] The present invention has been described by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.

Claims

1. A metal powder injection molding apparatus for gear processing, comprising a body (1), wherein the body (1) is provided with an injection unit (2), a mold clamping unit (3), a mold assembly (4), and a power drive system (5), wherein the mold clamping unit (3) includes a fixed template (31), wherein the fixed template (31) is provided with a nozzle through hole (312), characterized in that The template (31) near the injection unit (2) is provided with a receiving and switching mechanism (6) and a cleaning mechanism (7). The receiving and switching mechanism (6) includes a switching disk (61), which has two mounting holes (611) and an annular mounting groove (612) on the outer edge of each mounting hole (611). The mounting holes (611) have the same diameter as the nozzle through hole (312). Each mounting groove is provided with an electromagnetic receiving assembly (63). The electromagnetic receiving assembly (63) includes an annular electromagnet (631) and a receiving sleeve (632). The annular electromagnet (631) is embedded in the annular mounting groove (612), and the receiving sleeve (632) is located in the annular mounting groove (612). Inside the nozzle through hole (312), the end face of the receiving sleeve (632) in the lower electromagnetic receiving assembly (63) near the mold assembly (4) is flush with the back of the fixed template (31), and the end face of the receiving sleeve (632) in the upper electromagnetic receiving assembly (63) near the mold assembly (4) is flush with the front of the fixed template (31). The cleaning mechanism (7) includes a cover (71), and two interface positions on the cover (71) are rotatably connected to a rotating shaft (72) and a composite shaft (74), respectively. A gear (73) is provided on the rotating shaft (72), and a toothed part (613) is bonded to the gear (73). The toothed part (613) is located at the outer edge of the switching disk (61).

2. The metal powder injection molding apparatus for gear processing according to claim 1, characterized in that, The center of the switching disk (61) is connected to a support shaft (62) by bolts. The support shaft (62) is rotatably connected to the interface of the fixed template (31). A bearing (311) is provided in the gap between the support shaft (62) and the interface of the fixed template (31).

3. The metal powder injection molding apparatus for gear processing according to claim 2, characterized in that, Multiple springs (634) are equidistantly arranged between the annular electromagnet (631) and the receiving sleeve (632). Multiple limiting grooves (633) are equidistantly arranged around the outer shell of the annular electromagnet (631), and the springs (634) are sleeved on the corresponding limiting grooves (633). Each limiting groove (633) is movably connected to a limiting head (635), and the limiting head (635) is installed on the receiving sleeve (632) by bolts.

4. The metal powder injection molding apparatus for gear processing according to claim 3, characterized in that, Limiting bolts (636) are movably connected in the circular holes on both sides of the receiving sleeve (632), and the limiting bolts (636) are engaged with the threaded holes on the corresponding annular mounting groove (612).

5. The metal powder injection molding apparatus for gear processing according to claim 1, characterized in that, The composite shaft (74) includes a connecting part (741), a receiving part (742) and a plug-in part (744). A plurality of bending cleaning plates (743) are equidistantly arranged around the receiving part (742). The bending cleaning plate (743) includes an inner wall cleaning part (7431) and an end face cleaning part (7432).

6. The metal powder injection molding apparatus for gear processing according to claim 5, characterized in that, The cover (71) has a sliding opening (711) on its lower side, and a collection groove (75) is movably connected inside the sliding opening (711).

7. The metal powder injection molding apparatus for gear processing according to claim 6, characterized in that, The cover (71) is bolted to a first motor (76) and a drive assembly (77), and the output end of the first motor (76) is connected to one end of the rotating shaft (72).

8. The metal powder injection molding apparatus for gear processing according to claim 7, characterized in that, The drive assembly (77) includes a support frame (771), which is bolted to the outer wall of the cover (71). The support frame (771) is provided with two limit rods (772), which are parallel to each other. A sliding plate (773) is provided on both limit rods (772). A second motor (774) is bolted to the sliding plate (773). The output end of the second motor (774) is connected to the connection part (741) of the composite shaft (74). A cylinder (775) is bolted to the support frame (771). A push frame (776) is provided at the output end of the cylinder (775). The push frame (776) is bolted to the upper side of the housing of the second motor (774).

9. The metal powder injection molding apparatus for gear processing according to claim 1, characterized in that, The upper side of the fixed template (31) is provided with an installation port (313), and a purging mechanism (8) is provided in the installation port (313). The purging mechanism (8) includes a cavity (81) and an end cap (83), and the cavity (81) and the end cap (83) are connected by bolts. A purging cover (82) is rotatably connected in the interface on the side wall of the cavity (81). A shaft seal (84) is provided in the gap between the purging cover (82) and the interface on the side wall of the cavity (81). A plug groove (821) is provided at the center of the purging cover (82), and the plug groove (821) fits with the plug part (744). Multiple air outlets (822) are provided equidistantly in the circumferential direction of the plug groove (821). An air inlet connector (831) is provided on the upper side of the end cap (83).

10. A method for metal powder injection molding apparatus for gear processing, characterized in that, The specific steps of the metal powder injection molding apparatus for gear processing according to any one of claims 1-9 are as follows: S1 Separation Preparation: When there is residual molten metal powder and binder mixture on the inner wall and end face of the receiving sleeve (632), the annular electromagnet (631) in the lower electromagnetic receiving assembly (63) is de-energized, the traction force of the annular electromagnet (631) on the receiving sleeve (632) disappears, the compressed return spring (634) is restored to its original shape, and a force is applied to the receiving sleeve (632) in the direction of the injection unit (2), so that the receiving sleeve (632) slides along the limit bolt (636) and abuts against the head of the limit bolt (636), and the end of the receiving sleeve (632) near the mold assembly (4) separates from the nozzle through hole (312) of the fixed platen (31); S2 Rotation Switching: The first motor (76) drives the gear (73) to rotate through the shaft (72). The gear (73) meshes with the toothed part (613) on the switching disk (61). Subsequently, the switching disk (61) rotates around the support shaft (62) as the fulcrum, and the two electromagnetic receiving components (63) are swapped. The receiving sleeve (632) with residual material in the lower electromagnetic receiving component (63) is moved to the upper part, and the receiving sleeve (632) without residual material in the upper electromagnetic receiving component (63) is moved to the lower part. S3 Reassembly: The annular electromagnet (631) in the lower electromagnetic receiving assembly (63) is energized and a traction force is generated on the receiving sleeve (632) without residual material, which is attracted. Then the receiving sleeve (632) moves closer to the mold assembly (4) along the limiting bolt (636), the spring (634) is compressed, and then the limiting groove (633) and the limiting head (635) are fully inserted together. At the same time, the end face of the receiving sleeve (632) on the side close to the mold assembly (4) is flush with the back of the fixed template (31), and the assembly is completed. S4 Scraping and Cleaning: The cylinder (775) pulls the second motor (774) along the limit rod (772) to the side of the receiving sleeve (632) with residual material in the upper electromagnetic receiving assembly (63) via the push frame (776), and causes the plug part (744) on the composite shaft (74) to be inserted into the plug slot (821) of the blow cover (82). Then the second motor (774) drives the composite shaft (74) to rotate, and the bending cleaning blade (743) on the composite shaft (74) rotates to scrape. The inner wall cleaning part (7431) and the end face cleaning part (7432) on the bending cleaning blade (743) clean the residue on the inner wall and end face of the receiving sleeve (632) respectively. S5 Purging and Collection: While the composite shaft (74) rotates, the purging cover (82) on the cavity (81) rotates. The high-pressure gas in the cavity (81) is ejected from the air outlet (822) on the purging cover (82) and rotates to purge the inner wall of the receiving sleeve (632). The material removed is blown to one side of the inner wall of the cover (71) and then falls down the inner wall of the cover (71) into the collection tank (75) for collection.

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