A powder metallurgy injection molding device and method thereof

Abstract

The present invention discloses a powder metallurgy injection molding device, comprising a workbench, a mixing mechanism fixedly mounted on the other side of the top of the workbench, a degassing mechanism fixedly mounted on the side of the top of the workbench close to the mixing mechanism, and a driving mechanism mounted on the other side of a mixing box via a protective cover. The present invention drives the mixing mechanism, injection mechanism, mounting seat, and mold assembly to operate synchronously through the driving mechanism, thereby enabling the screening, mixing, material equalization, injection, sealing space, mold closing, and mold opening of raw materials, reducing energy consumption generated by the operation of the device, screening the powder through the screening assembly to make the powder more uniform, and helping to reduce bubble retention caused by particle size differences during the degassing process, extracting gas from the mixture through a vacuum pump, effectively reducing the generation of bubbles and eliminating residual bubbles, and the degassed powder can form a more dense and uniform product structure in subsequent processing, thereby improving the overall quality and performance of the product.

Description

Technical Field

[0001] The present invention relates to the technical field of powder metallurgy, in particular to a powder metallurgy injection molding device and a method thereof. Background Art

[0002] Powder metallurgy injection molding is a new type of powder metallurgy near-net molding technology derived from the plastic injection molding industry. It integrates cross-disciplinary knowledge such as plastic molding technology, polymer chemistry, powder metallurgy technology and metal materials science. It uses metal powder or a mixture of metal powder and non-metallic powder as raw materials. The organic binder is injected into the mold cavity by the injection molding machine in a heated and plasticized state to solidify the molded blank. The product shape is formed by the mold, and high-density, high-precision, three-dimensional complex-shaped structural parts are quickly manufactured through sintering. Powder metallurgy injection molding technology is widely used in industrial fields such as electronic information engineering, biomedical equipment, office equipment, automobiles, machinery, hardware, sports equipment, watch industry, weapons and aerospace.

[0003] However, in actual use, similar structures still have many defects. For example, they do not have the function of degassing. If bubbles remain in the product, it will affect its density, mechanical properties and appearance quality. Incomplete degassing can easily lead to defects such as blistering and cracks, resulting in a decrease in the yield rate. For this reason, we propose a powder metallurgy injection molding device and method to solve the existing problems. Summary of the Invention

[0004] The purpose of the present invention is to solve the shortcomings existing in the prior art, such as: the lack of degassing function, if bubbles remain in the product, it will affect its density, mechanical properties and appearance quality; incomplete degassing can easily lead to defects such as bubbles and cracks, resulting in a decrease in the yield rate.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A powder metallurgy injection molding device comprises a workbench, a mounting box fixedly mounted on one side of the top of the workbench, a mounting seat embedded in one side of the mounting box, a mold assembly fixedly mounted on one side of the mounting seat, and the mold assembly is placed inside the mounting box;

[0007] A mixing mechanism is fixedly installed on the other side of the top of the workbench, and the mixing mechanism includes a mixing tank fixedly installed on the top of the workbench, a mixing box fixedly installed on the bottom of the mixing tank, a stirring rod rotatably installed at the bottom of the mixing box, and a driven bevel gear is installed on the top of the stirring rod through a connecting rod. A screening assembly is movably installed inside the mixing tank, and a transmission rod extending to the inside of the mixing box is fixedly installed at the bottom of the screening assembly, a stirring paddle is sleeved on the outer side of the transmission rod, and a driven bevel gear is fixedly installed on the bottom end of the transmission rod;

[0008] An injection mechanism is installed on one side of the mixing box, one end of the injection mechanism is connected to the mounting seat, a degassing mechanism is fixedly installed on the top of the workbench close to the mixing mechanism, and a driving mechanism is installed on the other side of the mixing box through a protective cover, and the driving mechanism is respectively connected to the mixing mechanism, injection mechanism, mounting seat and mold assembly.

[0009] Furthermore, the screening assembly includes a rotating disk rotatably installed inside the mixing tank, and a screening disk movably installed inside the mixing tank through a slide groove. Inclined wedges are equidistantly installed on the top of the rotating disk, and resistance rods are equidistantly installed on the bottom of the screening disk. When the resistance rods pass through the inclined wedges, the screening disk vibrates vertically, thereby realizing vertical vibration screening of the powder on the top of the screening disk.

[0010] Furthermore, the injection mechanism includes an injection tube fixedly installed on one side of the mixing box, a second heater is sleeved on the outer side of the injection tube, and a screw is rotatably installed inside the injection tube.

[0011] Furthermore, a valve disc is rotatably mounted inside the mounting seat, and material passage holes are equidistantly provided inside the valve disc.

[0012] Furthermore, the mold assembly includes a sliding rod fixedly installed on the inner wall of the mounting box, and a fixed mold fixedly installed on one side of the mounting seat. A demolding air hole is opened on one side of the fixed mold. A movable seat is movably installed on the outer side of the sliding rod. A wire kit is embedded in the interior of the movable seat. A reciprocating screw rod is installed inside the wire kit. A movable mold is fixedly installed on one side of the movable seat.

[0013] Furthermore, the driving mechanism includes a speed-regulating motor installed inside the protective box, and a first pulley group is fixedly installed on the output end of the speed-regulating motor, and a bevel gear rod extending to the inside of the mixing box is fixedly installed on the top of one side of the first pulley group, and the top of one end of the bevel gear rod is meshed with the driven bevel gear at the bottom of the transmission rod, and the bottom of one end of the bevel gear rod is meshed with the driven bevel gear at the top of the stirring rod, one end of the bevel gear rod is fixedly connected to one end of the screw through a connecting rod, a second pulley group is installed on the bottom of one side of the first pulley group through a linkage rod, the top of one side of the second pulley group is fixedly connected to the reciprocating screw through a connecting rod, and the bottom of one side of the second pulley group is clamped to the valve disc through a clamping rod.

[0014] Furthermore, the degassing mechanism includes a high-pressure gas tank fixedly installed on one side of the top of the workbench, a negative pressure pump is installed at the bottom of the high-pressure gas tank through a pipeline, the suction end of the negative pressure pump is connected to the mixing box through a negative pressure pipe, and a solenoid valve is fixedly installed on the top of the high-pressure gas tank through a high-pressure pipe. The solenoid valve is fixedly installed on one side of the fixed mold, and the solenoid valve is connected to the demolding air hole.

[0015] Furthermore, a controller is fixedly installed on the top of the workbench, a protection box is fixedly installed on one side of the top of the workbench, and the speed regulating motor and the negative pressure pump are both fixedly installed inside the protection box.

[0016] A powder metallurgy injection molding method, the injection molding method comprising the following steps:

[0017] Step 1: The driving mechanism drives the mixing mechanism, injection mechanism, mounting base, and mold assembly to operate synchronously, and the powder is put into the mixing tank. The powder is screened by the running screening assembly and then falls to the bottom of the mixing tank. The raw materials in the mixing tank are heated and melted by the first heater, and the raw materials are mixed by the rotating stirring paddle. The mixed molten raw materials enter the mixing box and are stirred, mixed, and exhausted by the rotating stirring rod.

[0018] Step 2: When the molten raw materials are stirred and mixed, the negative pressure pump extracts the vacuum inside the mixing box through the negative pressure pipe and transports the sucked air to the high-pressure gas tank for storage, thereby removing bubbles from the molten raw materials. After the bubbles are removed, the raw materials are injected under the push of the rotating screw, and the raw materials inside the injection tube are further heated by the running second heater to ensure the fluidity of the molten raw materials.

[0019] Step 3: When the raw material is pushed to the discharge port of the injection tube for injection, the movable mold and the fixed mold are docked and closed to form a mold cavity. At this time, the rotating valve disc drives the through hole to dock with the fixed mold and the discharge port of the injection tube. The raw material inside the injection tube is injected into the mold cavity through the through hole. When the raw material injection is completed, the controller controls the speed regulating motor to stop running;

[0020] Step 4: The raw materials are cooled in the mold cavity to form products. When the products are demolded, the solenoid valve is opened, and the high-pressure gas stored in the high-pressure gas tank is transported to the solenoid valve through the high-pressure pipe. The solenoid valve transports the high-pressure gas into the mold cavity through the demolding holes, and the gas in the mold cavity is stripped. When the movable mold is separated from the fixed mold, the product is automatically demolded.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention drives the mixing mechanism, injection mechanism, mounting seat, and mold assembly to operate synchronously through a driving mechanism, thereby realizing screening, mixing, material equalization, injection, space sealing, mold closing, and mold opening of raw materials, thereby reducing energy consumption generated by the operation of the device. Screening the powder by the screening assembly can make the powder more uniform, which helps to reduce the bubble retention phenomenon caused by particle size differences during the degassing process. When the powder with uniform particle size is stirred, bubbles are more easily discharged, and the fluidity of the metal powder is improved, so that the powder is more evenly distributed in the degassing container, thereby accelerating the rise and discharge of bubbles. In addition, the powder with uniform particle size can be more densely packed together during pressing, thereby reducing the generation of pores and bubbles.

[0023] The raw materials in the mixing tank are mixed by a stirring paddle and the raw materials inside the mixing box are mixed by a stirring rod to ensure uniform mixing and avoid the generation of local bubbles. The mixed raw materials are vacuum degassed in conjunction with the degassing mechanism, and the gas in the mixture is extracted by a vacuum pump, effectively reducing the generation of bubbles and eliminating residual bubbles. The degassed powder can form a denser and more uniform product structure in subsequent processing, thereby improving the overall quality and performance of the product. The gas generated by vacuum extraction is used to perform gas stripping and demoulding on the product in the mold assembly, ensuring the integrity of the product during demoulding, facilitating subsequent product unloading, and improving the efficiency of product injection molding. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a front structural schematic diagram of the present invention;

[0025] Figure 2 It is a schematic diagram of the back side of the present invention;

[0026] Figure 3 Schematic diagram of the internal structure of the present invention;

[0027] Figure 4 Schematic diagram of the cross-sectional structure of the present invention

[0028] Figure 5 This is a schematic diagram of the internal structure of the installation box of the present invention;

[0029] Figure 6 It is a schematic diagram of the partial structure of the installation box of the present invention;

[0030] Figure 7 Schematic diagram of the internal structure of the mixing mechanism of the present invention;

[0031] Figure 8 It is a schematic diagram of the partial structure of the screening assembly of the present invention;

[0032] Figure 9 Schematic diagram of the internal structure of the mixing box of the present invention;

[0033] Figure 10It is a schematic diagram of the local structure of the injection mechanism of the present invention;

[0034] Figure 11 It is a schematic diagram of the local structure of the driving mechanism of the present invention;

[0035] Figure 12 Schematic diagram of the internal structure of the mold assembly of the present invention;

[0036] Figure 13 It is a schematic diagram of the partial structure of the degassing mechanism of the present invention;

[0037] Figure 14 It is a schematic diagram of the internal structure of the fixed mold of the present invention.

[0038] In the figure: 1. Workbench; 101. Controller; 102. Protective box; 2. Mixing mechanism; 201. Mixing tank; 202. First heater; 203. Mixing box; 204. Transmission rod; 205. Driven bevel gear; 206. Stirring paddle; 207. Screening assembly; 2071. Rotating disk; 2072. Screening disk; 2073. Interference rod; 2074. Inclined wedge; 208. Stirring rod; 3. Injection mechanism; 301. Injection tube; 302. Second heater; 303. Screw; 4. Mounting box; 5. Mounting seat; 501, valve disc; 502, material passage hole; 6, driving mechanism; 601, speed regulating motor; 602, first pulley group; 603, bevel gear rod; 604, linkage rod; 605, second pulley group; 7, mold assembly; 701, sliding rod; 702, movable seat; 703, wire set; 704, reciprocating screw rod; 705, movable mold; 706, fixed mold; 707, demoulding air hole; 8, degassing mechanism; 801, high-pressure gas tank; 802, negative pressure pump; 803, high-pressure pipe; 804, solenoid valve. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0040] In the description of the present invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," "the other end," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "provided with," "connected," etc., should be understood in a broad sense. For example, "connected" may refer to a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0042] See also Figure 1-14 The present invention provides a powder metallurgy injection molding device, comprising a workbench 1, a mounting box 4 fixedly mounted on one side of the top of the workbench 1, a mounting seat 5 embedded in one side of the mounting box 4, a mold assembly 7 fixedly mounted on one side of the mounting seat 5, and the mold assembly 7 is placed inside the mounting box 4;

[0043] A mixing mechanism 2 is fixedly installed on the other side of the top of the workbench 1. The mixing mechanism 2 includes a mixing tank 201 fixedly installed on the top of the workbench 1, a mixing box 203 fixedly installed on the bottom of the mixing tank 201, a stirring rod 208 rotatably installed at the bottom of the mixing box 203, a driven bevel gear 205 is installed on the top of the stirring rod 208 through a connecting rod, a screening assembly 207 is movably installed inside the mixing tank 201, a transmission rod 204 extending into the interior of the mixing box 203 is fixedly installed at the bottom of the screening assembly 207, a stirring paddle 206 is sleeved on the outer side of the transmission rod 204, and a driven bevel gear 205 is fixedly installed on the bottom end of the transmission rod 204;

[0044] An injection mechanism 3 is installed through one side of the mixing box 203, and one end of the injection mechanism 3 is connected to the mounting base 5. A degassing mechanism 8 is fixedly installed on the top of the workbench 1 near the mixing mechanism 2. A driving mechanism 6 is installed on the other side of the mixing box 203 through a protective cover. The driving mechanism 6 is respectively connected to the mixing mechanism 2, the injection mechanism 3, the mounting base 5, and the mold assembly 7.

[0045] It should be noted that a track door is installed on the front of the installation box 4 through a slide rail groove. Closing the track door can form a closed whole inside the installation box 4, protecting the internal mold assembly 7 from damage by external forces, and ensuring the safety of injection when injecting raw materials into the mold assembly 7, avoiding burns caused by overflow of excess raw materials, thereby improving the safety effect of the device.

[0046] A protective cover is fixedly installed on one side of the interior of the mixing box 203. The protective cover is sleeved on the outer sides of the driven bevel gear 205 and the bevel gear rod 603 to protect the driven bevel gear 205 from being driven by the bevel gear rod 603, thereby preventing the molten raw materials from sticking to the surfaces of the driven bevel gear 205 and the bevel gear rod 603 and causing transmission jams, thereby ensuring the stability of the transmission of the driven bevel gear 205 and the bevel gear rod 603.

[0047] The stirring paddle 206 is composed of a stirring bracket and a stirring scraper, and the stirring bracket is in contact with the inner wall of the mixing tank 201. The stirring scraper rotates under the driving force of the rotating stirring bracket, and the rotating stirring scraper rotates on its own. The self-rotating stirring scraper can accelerate the mixing of the raw materials inside the mixing tank 201, thereby improving the mixing efficiency of the raw materials inside the mixing tank 201. At the same time, the rotating stirring bracket and the stirring scraper can clean the inner wall of the mixing tank 201 to avoid residual raw materials, thereby reducing the subsequent cleaning burden on the staff.

[0048] The degassing mechanism 8 can store air while performing vacuuming, providing demoulding gas for the mold assembly 7, thereby improving the demoulding integrity and demoulding efficiency of the product.

[0049] See also Figure 5-9 The screening assembly 207 includes a rotating disk 2071 rotatably mounted inside the mixing tank 201, and a screening disk 2072 movably mounted inside the mixing tank 201 via a chute. Inclined wedges 2074 are equidistantly mounted on the top of the rotating disk 2071, and abutment rods 2073 are equidistantly mounted on the bottom of the screening disk 2072. The abutment rods 2073 vertically vibrate the screening disk 2072 via the inclined wedges 2074, thereby achieving vertical vibration screening of the powder on the top of the screening disk 2072.

[0050] It should be noted that: the rotating disk 2071 rotates and moves inside the mixing tank 201 through the slip ring, and the screening disk 2072 vibrates vertically in cooperation with the slide rail on the inner wall of the mixing tank 201 through the slide groove. Under the rotation of the rotating disk 2071, the inclined wedge block 2074 is intermittently connected to the resistance rod 2073, and the screening disk 2072 is lifted when the inclined wedge block 2074 is in resistance contact with the resistance rod 2073. When the inclined wedge block 2074 is separated from the resistance rod 2073, the screening disk 2072 falls, thereby causing the screening disk 2072 to vibrate vertically.

[0051] See also Figure 10The injection mechanism 3 includes an injection tube 301 fixedly mounted on one side of the mixing box 203, a second heater 302 is sleeved on the outer side of the injection tube 301, and a screw 303 is rotatably mounted inside the injection tube 301;

[0052] It should be noted that: when the second heater 302 is powered on, the heat generated is transferred to the inside of the injection tube 301, heating the raw material inside the injection tube 301, thereby ensuring the fluidity of the molten raw material for subsequent injection.

[0053] See also Figure 10-11 A valve disc 501 is rotatably mounted inside the mounting seat 5, and material passage holes 502 are equidistantly opened inside the valve disc 501;

[0054] It should be noted that: when the valve disc 501 drives the through hole 502 to dock with the discharge port of the injection tube 301, the movable mold 705 and the fixed mold 706 are docked until they are completely closed. When the through hole 502 is separated from the discharge port of the injection tube 301, the movable mold 705 moves away from the fixed mold 706. The single movement stroke of the movable mold 705 is half of the stroke of the through hole 502 rotating to dock with the discharge port of the injection tube 301. Therefore, when the movable mold 705 and the fixed mold 706 dock again, the through hole 502 is docked with the discharge port of the injection tube 301.

[0055] See also Figure 11 The mold assembly 7 includes a slide rod 701 fixedly mounted on the inner wall of the mounting box 4, and a fixed mold 706 fixedly mounted on one side of the mounting seat 5. A demoulding air hole 707 is opened on one side of the fixed mold 706. A movable seat 702 is movably mounted on the outer side of the slide rod 701. A wire set 703 is embedded in the interior of the movable seat 702. A reciprocating screw rod 704 is installed in the interior of the wire set 703. A movable mold 705 is fixedly mounted on one side of the movable seat 702.

[0056] It should be noted that the reciprocating screw 704 drives the movable seat 702 to move back and forth through the wire kit 703, and the reciprocating movable seat 702 drives the movable mold 705 to move back and forth horizontally. When the movable mold 705 moves to dock with the fixed mold 706, the reciprocating screw 704 continues to rotate and drives the movable seat 702 to move in the opposite direction through the wire kit 703. The reverse moving movable seat 702 drives the movable mold 705 to move in the opposite direction away from the fixed mold 706, so as to facilitate demolding of the product. An exhaust channel is provided on the top of the movable mold 705 so that the gas generated during the product molding process can be discharged in time.

[0057] See also Figure 5-12The driving mechanism 6 includes a speed regulating motor 601 installed inside the protective box 102, and a first pulley group 602 is fixedly installed on the output end of the speed regulating motor 601. A bevel gear rod 603 extending to the inside of the mixing box 203 is fixedly installed on the top of one side of the first pulley group 602, and the top of one end of the bevel gear rod 603 is meshed and connected with the driven bevel gear 205 at the bottom of the transmission rod 204, and the bottom of one end of the bevel gear rod 603 is meshed and connected with the driven bevel gear 205 at the top of the stirring rod 208, one end of the bevel gear rod 603 is fixedly connected to one end of the screw 303 through a connecting rod, and a second pulley group 605 is installed on the bottom of one side of the first pulley group 602 through a linkage rod 604, and the top of one side of the second pulley group 605 is fixedly connected to the reciprocating screw rod 704 through a connecting rod, and the bottom of one side of the second pulley group 605 is clamped with the valve disc 501 through a clamping rod;

[0058] It should be noted that: the speed regulating motor 601 is powered on and drives the bevel gear rod 603 and the linkage rod 604 to rotate synchronously through the first pulley group 602. The rotating bevel gear rod 603 drives the transmission rod 204 and the stirring rod 208 to rotate synchronously through the engaged driven bevel gear 205. At the same time, the rotating bevel gear rod 603 drives the screw 303 to rotate, and the rotating transmission rod 204 drives the stirring paddle 206 and the rotating disk 2071 to rotate. The rotating linkage rod 604 drives the valve disc 501 through the second pulley group 605 and drives the reciprocating screw rod 704 to rotate synchronously through the connecting rod.

[0059] See also Figure 13-14 The degassing mechanism 8 includes a high-pressure gas tank 801 fixedly mounted on one side of the top of the workbench 1. A negative pressure pump 802 is installed at the bottom of the high-pressure gas tank 801 through a pipeline. The suction end of the negative pressure pump 802 is connected to the mixing box 203 through a negative pressure pipe. A solenoid valve 804 is fixedly mounted on the top of the high-pressure gas tank 801 through the high-pressure pipe 803. The solenoid valve 804 is fixedly mounted on one side of the fixed mold 706, and the solenoid valve 804 is connected to the demoulding air hole 707.

[0060] It should be noted that: the negative pressure pump 802 is powered on and running, and the negative pressure pump 802 draws the vacuum inside the mixing box 203 through the negative pressure pipe, and transports the sucked air to the high-pressure gas tank 801 for storage. The solenoid valve 804 is opened, and the high-pressure pipe 803 transports the high-pressure air inside the high-pressure gas tank 801 into the mold cavity, and the product in the mold cavity is gas-stripped and demolded.

[0061] See also Figure 1-4 , a controller 101 is fixedly installed on the top of the workbench 1, a protective box 102 is fixedly installed on one side of the top of the workbench 1, and the speed regulating motor 601 and the negative pressure pump 802 are both fixedly installed inside the protective box 102;

[0062] It should be noted that the controller 101 is electrically connected to the speed control motor 601, the negative pressure pump 802, and the solenoid valve 804 through wires to facilitate the operation of the control device. The protective box 102 can protect the speed control motor 601 and the negative pressure pump 802 to prevent the speed control motor 601 and the negative pressure pump 802 from being damaged by external forces, rain and dust, thereby ensuring the safety of the speed control motor 601 and the negative pressure pump 802.

[0063] A powder metallurgy injection molding method, the injection molding method comprising the following steps:

[0064] Step 1: Open the lid of the mixing tank 201, put powder and binder into the mixing tank 201, and the powder and binder fall on the top of the screening disk 2072. The controller 101 controls the speed regulating motor 601 to be powered on. The speed regulating motor 601 is powered on and drives the bevel gear rod 603 and the linkage rod 604 to rotate synchronously through the first pulley group 602. The rotating bevel gear rod 603 drives the transmission rod 204 and the stirring rod 208 to rotate synchronously through the meshing driven bevel gear 205. At the same time, the rotating bevel gear rod 603 drives the screw 303 to rotate, and the rotating transmission rod 204 drives the stirring paddle 206 and the rotating disk 2 071 rotates, and the rotating rotating disk 2071 intermittently contacts and connects with the interference rod 2073 through the equally spaced inclined wedges 2074. When the interference rod 2073 intermittently passes through the inclined wedge 2074, the screening disk 2072 is driven to vibrate vertically, thereby vibrating and screening the powder on the top of the screening disk 2072. The screened powder falls into the bottom of the mixing tank 201, and the raw materials in the mixing tank 201 are heated and melted by the first heater 202, and the raw materials are mixed by the rotating stirring paddle 206. The molten raw materials after mixing enter the interior of the mixing box 203, and are stirred, mixed and exhausted by the rotating stirring rod 208.

[0065] Step 2: When the molten raw materials are stirred and mixed, the controller 101 controls the negative pressure pump 802 to be powered on and run. The powered negative pressure pump 802 extracts the vacuum inside the mixing box 203 through the negative pressure pipe, and transmits the sucked air to the high-pressure gas tank 801 for storage, so that the raw materials are vacuum-exhausted inside the mixing box 203 to avoid residual bubbles in the raw materials. After the bubble removal process, the rotating screw 303 pushes the raw materials to the discharge port of the injection tube 301 for subsequent injection. At the same time, the raw materials inside the injection tube 301 are further heated by the running second heater 302 to ensure the fluidity of the molten raw materials.

[0066] Step 3: When the raw material is pushed to the discharge port of the injection tube 301 for injection, the rotating linkage rod 604 drives the valve disc 501 through the second pulley set 605 and drives the reciprocating screw rod 704 to rotate synchronously through the connecting rod. The rotating reciprocating screw rod 704 drives the movable seat 702 to move outside the slide rod 701 through the wire set 703. The movable movable seat 702 drives the movable mold 705 to move to the fixed mold 706 to dock and close to form a mold cavity. At this time, the rotating valve disc 501 drives the through hole 502 to dock with the fixed mold 706 and the discharge port of the injection tube 301, and the raw material inside the injection tube 301 is injected into the mold cavity through the through hole 502. When the injection is completed, the rotating valve disc 501 drives the through hole 502 to continue to rotate away from the injection tube 301, thereby blocking the raw material at the discharge port of the injection tube 301, so that a closed space is formed inside the injection tube 301 and inside the mixing box 203, which is convenient for vacuuming.

[0067] Step 4: The raw material is cooled in the mold cavity to form a product. When the product is demolded, the controller 101 controls the solenoid valve 804 to open, so that the demolding air hole 707 and the high-pressure pipe 803 form a passage. The high-pressure pipe 803 transports the high-pressure air inside the high-pressure gas tank 801 into the mold cavity to gas-peel off the product in the mold cavity. The controller 101 then controls the speed regulating motor 601 to energize and operate, so that the reciprocating screw rod 704 continues to rotate through the wire kit 703 to drive the movable seat 702 to move in the opposite direction. The movable seat 702 that moves in the opposite direction drives the movable mold 705 away from the fixed mold 706, so that the product is automatically demolded. After the demolding is completed, the above steps are repeated to inject the next product, which is convenient for the continuous injection molding process of the device.

[0068] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A powder metallurgy injection molding device, comprising a workbench (1), characterized in that: A mounting box (4) is fixedly mounted on one side of the top of the workbench (1), a mounting seat (5) is embedded in one side of the mounting box (4), a mold assembly (7) is fixedly mounted on one side of the mounting seat (5), and the mold assembly (7) is placed inside the mounting box (4); A mixing mechanism (2) is fixedly mounted on the other side of the top of the workbench (1), the mixing mechanism (2) comprising a mixing tank (201) fixedly mounted on the top of the workbench (1), a mixing box (203) fixedly mounted on the bottom of the mixing tank (201), a stirring rod (208) rotatably mounted on the bottom of the mixing box (203), a driven bevel gear (205) mounted on the top of the stirring rod (208) via a connecting rod, a screening assembly (207) movably mounted inside the mixing tank (201), a transmission rod (204) extending into the interior of the mixing box (203) fixedly mounted on the bottom of the screening assembly (207), a stirring paddle (206) sleeved on the outer side of the transmission rod (204), and a driven bevel gear (205) fixedly mounted on the bottom end of the transmission rod (204); An injection mechanism (3) is installed through one side of the mixing box (203), and one end of the injection mechanism (3) is connected to the mounting seat (5). A degassing mechanism (8) is fixedly installed on the top of the workbench (1) near the mixing mechanism (2). A driving mechanism (6) is installed on the other side of the mixing box (203) through a protective cover. The driving mechanism (6) is respectively connected to the mixing mechanism (2), the injection mechanism (3), the mounting seat (5), and the mold assembly (7). The mold assembly (7) includes a slide rod (701) fixedly mounted on the inner wall of the mounting box (4), and a fixed mold (706) fixedly mounted on one side of the mounting seat (5), a demoulding air hole (707) is provided on one side of the fixed mold (706), a movable seat (702) is movably mounted on the outer side of the slide rod (701), a wire assembly (703) is embedded in the interior of the movable seat (702), a reciprocating screw rod (704) is installed in the interior of the wire assembly (703), and a movable mold (705) is fixedly mounted on one side of the movable seat (702); The degassing mechanism (8) includes a high-pressure gas tank (801) fixedly mounted on one side of the top of the workbench (1); a negative pressure pump (802) is mounted on the bottom of the high-pressure gas tank (801) via a pipeline; a suction end of the negative pressure pump (802) is connected to the mixing box (203) via a negative pressure pipe; a solenoid valve (804) is fixedly mounted on the top of the high-pressure gas tank (801) via a high-pressure pipe (803); the solenoid valve (804) is fixedly mounted on one side of the fixed mold (706), and the solenoid valve (804) is connected to the demoulding air hole (707).

2. A powder metallurgy injection molding device according to claim 1, characterized in that: The screening assembly (207) comprises a rotating disc (2071) rotatably mounted inside the mixing tank (201), and a screening disc (2072) movably mounted inside the mixing tank (201) via a chute, wherein inclined wedges (2074) are equidistantly mounted on the top of the rotating disc (2071), and abutment rods (2073) are equidistantly mounted on the bottom of the screening disc (2072), and when the abutment rods (2073) pass through the inclined wedges (2074), the screening disc (2072) vibrates vertically, thereby achieving vertical vibration screening of the powder on the top of the screening disc (2072).

3. The powder metallurgy injection molding device according to claim 1, characterized in that: The injection mechanism (3) comprises an injection tube (301) fixedly mounted on one side of the mixing box (203), a second heater (302) being sleeved on the outside of the injection tube (301), and a screw (303) being rotatably mounted inside the injection tube (301).

4. The powder metallurgy injection molding device according to claim 1, characterized in that: A valve disc (501) is rotatably mounted inside the mounting seat (5), and material passage holes (502) are equidistantly provided inside the valve disc (501).

5. The powder metallurgy injection molding device according to claim 4, characterized in that: The driving mechanism (6) includes a speed regulating motor (601) installed inside the protective box (102), a first pulley group (602) is fixedly installed on the output end of the speed regulating motor (601), a bevel gear rod (603) extending into the interior of the mixing box (203) is fixedly installed on the top of one side of the first pulley group (602), and the top of one end of the bevel gear rod (603) is meshed with the driven bevel gear (205) at the bottom of the transmission rod (204), and the bottom of one end of the bevel gear rod (603) is meshed with the mixing rod (204). The driven bevel gear (205) at the top of the mixing rod (208) is meshed and connected, one end of the bevel gear rod (603) is fixedly connected to one end of the screw rod (303) through a connecting rod, the bottom of one side of the first pulley group (602) is installed with the second pulley group (605) through a linkage rod (604), the top of one side of the second pulley group (605) is fixedly connected to the reciprocating screw rod (704) through a connecting rod, and the bottom of one side of the second pulley group (605) is clamped to the valve disc (501) through a clamping rod.

6. The powder metallurgy injection molding device according to claim 5, characterized in that: A controller (101) is fixedly installed on the top of the workbench (1), a protective box (102) is fixedly installed on one side of the top of the workbench (1), and the speed regulating motor (601) and the negative pressure pump (802) are both fixedly installed inside the protective box (102).

7. A powder metallurgy injection molding method, comprising a powder metallurgy injection molding device according to any one of claims 1 to 6, characterized in that: The injection molding method includes the following steps: Step 1: The driving mechanism (6) drives the mixing mechanism (2), the injection mechanism (3), the mounting seat (5), and the mold assembly (7) to operate synchronously, and the powder is put into the mixing tank (201). The powder is screened by the running screening assembly (207) and then falls into the bottom of the mixing tank (201). The raw materials in the mixing tank (201) are heated and melted by the first heater (202), and the raw materials are mixed by the rotating stirring paddle (206). The mixed molten raw materials enter the interior of the mixing box (203), and are stirred, mixed, and exhausted by the rotating stirring rod (208); Step 2: When the molten raw materials are stirred and mixed, the negative pressure pump (802) extracts the vacuum inside the mixing box (203) through the negative pressure pipe, and transports the sucked air to the high-pressure gas tank (801) for storage, thereby performing a degassing process on the molten raw materials. After the degassing process, the molten raw materials are injected under the push of the rotating screw (303), and the raw materials inside the injection tube (301) are further heated by the running second heater (302), thereby ensuring the fluidity of the molten raw materials; Step 3: When the raw material is pushed to the discharge port of the injection tube (301) for injection, the movable mold (705) and the fixed mold (706) are docked and closed to form a mold cavity. At this time, the rotating valve disc (501) drives the through hole (502) to dock with the fixed mold (706) and the discharge port of the injection tube (301). The raw material inside the injection tube (301) is injected into the mold cavity through the through hole (502). When the injection of the raw material is completed, the controller (101) controls the speed regulating motor (601) to stop running; Step 4: The raw material is cooled in the mold cavity to form a product. When the product is demoulded, the solenoid valve (804) is opened, and the high-pressure gas stored in the high-pressure gas tank (801) is transported to the solenoid valve (804) through the high-pressure pipe (803). The solenoid valve (804) transports the high-pressure gas into the mold cavity through the demoulding hole (707), and the gas in the product in the mold cavity is stripped. When the movable mold (705) is separated from the fixed mold (706), the product is automatically demoulded.

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