Molding equipment for powder metallurgy of oil bearing and use method of molding equipment

Abstract

The invention belongs to the technical field of powder metallurgy forming equipment, and particularly relates to forming equipment for oil bearing powder metallurgy and a using method thereof.The forming equipment comprises a supporting table, a bottom plate is fixedly connected to the inner wall of the bottom end of the supporting table, an L-shaped frame is fixedly connected to the upper surface of the supporting table, and a through hole is formed in the top end of the L-shaped frame; and the hole wall of the through hole is fixedly connected with an extrusion mechanism, a first counter bore is formed in the inner wall of the top end of the supporting table, and the hole wall of the first counter bore is fixedly connected with a first sealing bearing. The oil bearing powder metallurgy forming equipment not only has the functions of sucking air to reduce the porosity of a metal powder material and shortening the extrusion processing period of the oil bearing, but also has the functions of preventing high temperature in forming of the metal powder material and preventing the metal powder material from adhering to a forming mold; the efficiency and the quality of extrusion processing of the oil bearing are improved, and the qualified rate and the reliability of processing of forming equipment can be further improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of powder metallurgy forming equipment, and particularly relates to a forming equipment for powder metallurgy of oil-impregnated bearings and a using method thereof. Background Art

[0002] An oil-impregnated bearing is a sliding bearing with a porous structure that can store lubricating oil, also known as a porous bearing. It mainly uses metal powder as raw material. The oil-impregnated bearing is a sintered body made by powder metallurgy method. Its working principle is to utilize the oil storage capacity of the internal pores of the material, and release lubricating oil through capillary action during operation to achieve self-lubrication without frequent maintenance. It is suitable for low-speed, medium and low load and non-lubricable scenarios. For example, the patent with the authorization announcement number CN209632121U discloses a powder metallurgy forming equipment.

[0003] The current forming equipment for powder metallurgy of oil-impregnated bearings has the following problems during use: During the extrusion process of powder materials, the metal powder materials are plastically deformed under high pressure (300 - 600 MPa), and are easily embedded in the microscopic grooves on the surface of the mold to form mechanical bite. At the same time, strong adhesion occurs between the metal powder and the mold surface due to intermolecular forces. When the formed oil-impregnated bearing is demolded, powder peeling occurs on the bearing surface due to the adhesion force, resulting in the surface roughness of the oil-impregnated bearing exceeding the standard and the porosity being abnormal. The rejection rate is as high as 15% - 20%, which affects the quality of powder metallurgy forming of oil-impregnated bearings, as well as the qualification rate and reliability of the powder metallurgy forming equipment for oil-impregnated bearings. After the powder material of the oil-impregnated bearing enters the mold cavity, the metal powder material is relatively loose and has a high porosity, resulting in the need for the mold to exhaust for a long time during the extrusion process of the oil-impregnated bearing powder material, significantly prolonging the forming cycle and affecting the efficiency of powder metallurgy forming of oil-impregnated bearings. At the same time, when the metal powder is extruded, heat is generated by friction between the metal powder and the mold (the local temperature rise can reach 150 - 200 °C), which is likely to cause local overheating or premature decomposition of the binder of the oil-impregnated bearing, making the oil-impregnated bearing prone to quality defects and further affecting the quality of powder metallurgy forming of oil-impregnated bearings.

[0004] Therefore, we propose a forming equipment for powder metallurgy of oil-impregnated bearings and a using method thereof to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a forming equipment for powder metallurgy of oil-impregnated bearings and a using method thereof for the above problems.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A molding device for powder metallurgy of oil-impregnated bearings, including a support table, the bottom inner wall of the support table is fixedly connected with a bottom plate, the upper surface of the support table is fixedly connected with an L-shaped frame, a through hole is opened at the top end of the L-shaped frame, and an extrusion mechanism is fixedly connected to the hole wall of the through hole; A first counterbore is opened on the top inner wall of the support table, and a first sealed bearing is fixedly connected to the hole wall of the first counterbore. The inner wall of the inner ring of the first sealed bearing is fixedly connected with a hollow forming outer mold. A hollow forming inner mold is arranged inside the hollow forming outer mold. The bottom end of the hollow forming inner mold is connected to the upper surface of the bottom plate through a rolling bearing. A forming mold cavity is jointly arranged between the inner wall of the hollow forming outer mold and the outer wall of the hollow forming inner mold. The outer wall of the hollow forming inner mold is movably sleeved with a bottom cylinder. The outer wall of the top end of the bottom cylinder is movably and hermetically contacted with the surface of the bottom mold cavity of the forming mold cavity. An air extraction mechanism is fixedly sleeved on the outer wall of the hollow forming outer mold; The bottom outer wall of the bottom plate is fixedly connected with a driving mechanism.

[0007] In the above-mentioned molding device for powder metallurgy of oil-impregnated bearings, the extrusion mechanism includes a first electro-hydraulic rod fixedly embedded in the top end of the support table. The moving end of the first electro-hydraulic rod is fixedly connected with a pressure cylinder that cooperates with the top of the forming mold cavity. A pressing plate is fixedly connected to the outer wall of the pressure cylinder. A damping telescopic rod is fixedly connected to the upper surface of the support table. The top end of the damping telescopic rod is fixedly connected with a pressing switch. The pressing end of the pressing switch is located below the pressing plate.

[0008] In the above-mentioned molding device for powder metallurgy of oil-impregnated bearings, two support rods are fixedly connected to the inner wall of the L-shaped frame. The bottom ends of the support rods are fixedly connected to the upper surface of the support table. A control box is fixedly connected to the upper surface of the L-shaped frame.

[0009] In the above-mentioned molding equipment for oil-impregnated bearing powder metallurgy, the air extraction mechanism includes a second sealing bearing fixedly sleeved on the outer wall of the hollow molding outer mold. The outer wall of the outer ring of the second sealing bearing is fixedly sleeved with an outer cover. The top end of the outer cover is fixedly connected to the inner wall of the top end of the support table. A plurality of first air intake sunken holes are formed in the inner wall of the hollow molding outer mold, and a first breathable ceramic block is fixedly connected to the hole wall of the first air intake sunken hole. A plurality of second air intake sunken holes are formed in the outer wall of the hollow molding inner mold, and a second breathable ceramic block is fixedly connected to the hole wall of the second air intake sunken hole. Breathable holes are formed in the outer wall of the hollow molding outer mold located inside the outer cover. The outer wall of the outer cover is fixedly communicated with a first air pipe. Two third sealing bearings are fixedly sleeved on the outer wall of the hollow molding inner mold. The outer walls of the outer rings of the two third sealing bearings are jointly fixedly sleeved with a hollow disc. The outer wall of the hollow disc is fixedly connected to the inner wall of the support table. An air extraction pump is fixedly connected to the upper surface of the bottom plate. The air intake end of the air extraction pump is fixedly communicated with a three-way reversing solenoid valve. The top air intake end of the three-way reversing solenoid valve is fixedly communicated with the bottom end of the hollow disc. Air outlet holes are formed in the outer wall of the hollow molding inner mold located inside the hollow disc. The bottom end of the first air pipe is fixedly connected to the upper surface of the hollow disc. Through holes are formed in the upper surface of the hollow disc, and a material ejecting mechanism is fixedly connected to the hole wall of the through hole. The air outlet end of the air extraction pump is fixedly communicated with an auxiliary mechanism.

[0010] In the above-mentioned molding equipment for oil-impregnated bearing powder metallurgy, the material ejecting mechanism includes a fixed pipe. An installation through hole matching with the fixed pipe is formed through the upper surface of the hollow disc. A second electric hydraulic rod is fixedly connected to the inner wall of the fixed pipe. The moving end of the second electric hydraulic rod is fixedly connected to the lower surface of the bottom cylinder.

[0011] In the above-mentioned molding equipment for oil-impregnated bearing powder metallurgy, the auxiliary mechanism includes a second air pipe fixedly communicated with the air outlet end of the air extraction pump. A through hole is formed in the outer wall of the outer cover, and a metal cover is fixedly connected to the hole wall of the through hole. The outer wall of the metal cover is in movable contact with the outer wall of the hollow molding outer mold. A semiconductor refrigeration sheet is fixedly connected to the inner wall of the metal cover. A heat sink is fixedly connected to the heat dissipation side surface of the semiconductor refrigeration sheet. The air outlet end of the second air pipe is fixedly connected to the inner wall of the opening side of the metal cover. A metal mesh cylinder is fixedly connected to the internal cavity of the hollow molding outer mold.

[0012] In the above-mentioned molding equipment for powder metallurgy of oil-impregnated bearings, the driving mechanism includes a driving motor fixedly connected to the bottom end of the bottom plate. The inner wall of the top end of the support table is connected to a rotating rod through a rolling bearing. The bottom end of the rotating rod is fixedly connected to the output end of the driving motor. The rod wall of the rotating rod is fixedly sleeved with a first gear and a second gear. The outer wall of the bottom end of the hollow molding outer mold is fixedly sleeved with a third gear meshing with the first gear. The outer wall of the bottom end of the hollow molding inner mold is fixedly sleeved with a fourth gear meshing with the second gear.

[0013] In the above-mentioned molding equipment for powder metallurgy of oil-impregnated bearings, the rotation speeds of the inner wall of the hollow molding outer mold and the outer wall of the hollow molding inner mold are the same.

[0014] A method for using a molding equipment for powder metallurgy of oil-impregnated bearings, the method comprising the following steps: Step S1: Before the quantitatively metered metal powder material of the oil-impregnated bearing is fed into the molding cavity composed of the hollow molding outer mold and the hollow molding inner mold, the molding cavity is made to form a negative pressure environment through an air extraction mechanism; Step S2: After the quantitatively metered metal powder of the oil-impregnated bearing is fed into the molding cavity, the molding cavity in the negative pressure environment will aspirate and compress the loose metal powder material; Step S3: Then, the first electro-hydraulic rod and the semiconductor refrigerating sheet are controlled to start through the control box. The moving end of the first electro-hydraulic rod pushes the pressing cylinder downward. After the pressing cylinder enters the molding cavity, the processing of the metal powder material extrusion is completed; Step S4: After the pressing cylinder drives the pressing plate to move downward, it will press the pressing switch. The pressing switch controls the three-way reversing solenoid valve and the driving motor to start. The driving motor drives the inner wall of the hollow molding outer mold and the outer wall of the hollow molding inner mold to have the same rotational linear speed through the driving mechanism; Step S5: While Step S4 is being carried out, the semiconductor refrigerating sheet is energized to cool the metal cover. The molding cavity can be cooled through the low-temperature metal cover. Moreover, the air discharged from the air outlet end of the air extraction pump can maintain the refrigerating effect of the semiconductor refrigerating sheet. When the pressing switch controls the three-way reversing solenoid valve to be energized, the air extraction pump transports a large amount of air into the metal cover of the auxiliary mechanism and assists in the heat dissipation work on the heat dissipation side of the semiconductor refrigerating sheet; Step S6: Finally, the oil-impregnated bearing powder metallurgy molding equipment controls the extrusion mechanism and the ejecting mechanism through the control box to eject the qualified molded oil-impregnated bearing from the molding cavity.

[0015] Compared with the existing technology, the advantages of a molding equipment for powder metallurgy of oil-impregnated bearings and its using method are as follows: Through the set air extraction mechanism, forming die cavity and control box, before the metal powder material of the oil-impregnated bearing is fed into the forming die cavity composed of the hollow outer forming die and the hollow inner forming die, the air extraction mechanism is started through the control box. The air extraction mechanism sucks the air in the forming die cavity, making the whole forming die cavity form a negative pressure environment. Then, when the quantified metal powder of the oil-impregnated bearing is fed into the forming die cavity, the forming die cavity in the negative pressure environment will suck and compress the loose metal powder material, reducing the porosity of the metal powder material. This process ensures that the pressing cylinder does not need to spend a lot of time exhausting air during the extrusion process of the metal powder material, thereby effectively reducing the extrusion processing cycle of the metal powder material. At the same time, the control box also controls the start of the first electro-hydraulic rod and the semiconductor refrigeration chip. This mechanism enables the oil-impregnated bearing powder metallurgy forming equipment to have the function of sucking air to reduce the porosity of the metal powder material, reducing the extrusion processing cycle of the oil-impregnated bearing, and improving the extrusion processing efficiency of the oil-impregnated bearing at the same time.

[0016] Through the set extrusion mechanism, driving mechanism and ejecting mechanism, while the pressing cylinder extrudes the metal powder material in the forming die cavity, the pressing plate will press the pressing switch. The pressing switch controls the three-way directional solenoid valve and the driving motor to be powered on and started. The driving mechanism makes the hollow outer forming die and the hollow inner forming die rotate, preventing the metal powder of the oil-impregnated bearing from adhering to the die wall. When the formed oil-impregnated bearing is demolded, its surface will not show powder peeling due to the lack of adhesion force. After the oil-impregnated bearing is formed, the formed oil-impregnated bearing can be pushed out through the ejecting mechanism. This mechanism enables the oil-impregnated bearing powder metallurgy forming equipment to have the function of preventing the metal powder material from adhering to the forming die, avoiding the occurrence of local powder shedding on the surface of the formed oil-impregnated bearing, reducing the surface roughness and porosity of the oil-impregnated bearing, not only improving the quality of the oil-impregnated bearing powder metallurgy forming, but also improving the qualified rate and reliability of the forming equipment processing.

[0017] Through the set auxiliary mechanism, after the semiconductor refrigeration chip is powered on, its refrigerating side cools the metal cover, and the low-temperature metal cover can cool the forming die cavity. When the pressing switch makes the three-way directional solenoid valve powered on, the three-way directional solenoid valve changes the air intake direction. At this time, the air extraction pump sucks a large amount of air and transports it to the metal cover, efficiently completing the heat dissipation work on the heat dissipation side of the semiconductor refrigeration chip, ensuring the refrigeration effect of the semiconductor refrigeration chip, further preventing the temperature of the forming die cavity from rising. In this way, when the metal powder material of the oil-impregnated bearing is subjected to extrusion processing friction, the local temperature will not rise sharply, avoiding the occurrence of local overburning of the oil-impregnated bearing or premature decomposition of the binder, and avoiding the generation of quality defects in the oil-impregnated bearing. This mechanism enables the oil-impregnated bearing powder metallurgy forming equipment to have the function of preventing high temperature during the forming of the metal powder material, enhancing the ability to avoid local quality defects in the oil-impregnated bearing, further improving the quality of the extrusion processing of the oil-impregnated bearing, and improving the reliability of the use of the forming equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 FIG. is a schematic structural diagram of a molding device for powder metallurgy of an oil-impregnated bearing and a method for using the same provided by the present invention; Figure 2 FIG. Figure 1 is a front view structural diagram of a molding device for powder metallurgy of an oil-impregnated bearing in FIG. ; Figure 3 FIG. Figure 2 is a partial sectional structural diagram in FIG. ; Figure 4 FIG. Figure 2 is a structural diagram of a damping telescopic rod part in FIG. ; Figure 5 FIG. Figure 2 is a structural diagram of a second breathable ceramic block part in FIG. ; Figure 6 FIG. Figure 2 is a three-dimensional structural diagram of a bottom cylinder in FIG. ; Figure 7 FIG. Figure 2 is a partially enlarged structural diagram in FIG. ; Figure 8 FIG. Figure 2 is a structural diagram of a hollow disc part in FIG. ; Figure 9 FIG. Figure 2 is a three-dimensional structural diagram of a hollow molding outer mold part in FIG. .

[0019] In the figure: 1 support table, 2 bottom plate, 3 L-shaped frame, 4 extrusion mechanism, 41 first electric hydraulic rod, 42 pressing cylinder, 43 pressing plate, 44 damping telescopic rod, 45 pressing switch, 5 first sealing bearing, 6 air extraction mechanism, 61 second sealing bearing, 62 outer cover, 63 first breathable ceramic block, 64 second breathable ceramic block, 65 air permeation hole, 66 first air pipe, 67 third sealing bearing, 68 hollow disc, 69 air extraction pump, 610 three-way reversing solenoid valve, 611 air outlet hole, 7 ejecting mechanism, 71 fixed pipe, 72 second electric hydraulic rod, 8 auxiliary mechanism, 81 second air pipe, 82 metal cover, 83 semiconductor refrigeration sheet, 84 heat sink, 85 metal mesh cylinder, 9 driving mechanism, 91 driving motor, 92 rotating rod, 93 first gear, 94 second gear, 95 third gear, 96 fourth gear, 10 hollow molding outer mold, 11 hollow molding inner mold, 12 molding cavity, 13 bottom cylinder, 14 support rod, 15 control box. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0021] As Figures 1 - 9 shown, a molding device for powder metallurgy of an oil-containing bearing includes a support table 1. The bottom inner wall of the support table 1 is fixedly connected with a bottom plate 2. The upper surface of the support table 1 is fixedly connected with an L-shaped frame 3. The inner wall of the L-shaped frame 3 is fixedly connected with two support rods 14. The bottom ends of the support rods 14 are fixedly connected with the upper surface of the support table 1. The upper surface of the L-shaped frame 3 is fixedly connected with a control box 15. A through hole is opened at the top end of the L-shaped frame 3, and the hole wall of the through hole is fixedly connected with an extrusion mechanism 4. The extrusion mechanism 4 includes a first electro-hydraulic rod 41 fixedly embedded in the top end of the support table 1. The moving end of the first electro-hydraulic rod 41 is fixedly connected with a pressure cylinder 42 that cooperates with the top of the molding cavity 12. The outer wall of the pressure cylinder 42 is fixedly connected with a pressing plate 43. The upper surface of the support table 1 is fixedly connected with a damping telescopic rod 44. The top end of the damping telescopic rod 44 is fixedly connected with a pressing switch 45. The pressing end of the pressing switch 45 is located below the pressing plate 43.

[0022] The inner wall of the top end of the support platform 1 is provided with a first counterbore, and the inner wall of the hole wall of the first counterbore is fixedly connected with a first sealing bearing 5. The inner wall of the inner ring of the first sealing bearing 5 is fixedly connected with a hollow forming outer mold 10. A hollow forming inner mold 11 is arranged inside the hollow forming outer mold 10. The bottom end of the hollow forming inner mold 11 is connected to the upper surface of the bottom plate 2 through a rolling bearing. A forming mold cavity 12 is jointly arranged between the inner wall of the hollow forming outer mold 10 and the outer wall of the hollow forming inner mold 11. The outer wall of the hollow forming inner mold 11 is movably sleeved with a bottom cylinder 13. The outer wall of the top end of the bottom cylinder 13 is in movable sealing contact with the surface of the bottom mold cavity of the forming mold cavity 12. The outer wall of the hollow forming outer mold 10 is fixedly sleeved with an air extraction mechanism 6. The air extraction mechanism 6 includes a second sealing bearing 61 fixedly sleeved on the outer wall of the hollow forming outer mold 10. The outer wall of the outer ring of the second sealing bearing 61 is fixedly sleeved with an outer cover 62. The top end of the outer cover 62 is fixedly connected with the inner wall of the top end of the support platform 1. The inner wall of the hollow forming outer mold 10 is provided with a plurality of first air inlet counterbores, and the inner wall of the hole wall of the first air inlet counterbore is fixedly connected with a first breathable ceramic block 63. The outer wall of the hollow forming inner mold 11 is provided with a plurality of second air inlet counterbores, and the inner wall of the hole wall of the second air inlet counterbore is fixedly connected with a second breathable ceramic block 64. The outer wall of the hollow forming outer mold 10 located inside the outer cover 62 is provided with air holes 65. The outer wall of the outer cover 62 is fixedly communicated with a first air pipe 66. The outer wall of the hollow forming inner mold 11 is fixedly sleeved with two third sealing bearings 67. The outer walls of the outer rings of the two third sealing bearings 67 are jointly fixedly sleeved with a hollow disc 68. The outer wall of the hollow disc 68 is fixedly connected with the inner wall of the support platform 1. The upper surface of the bottom plate 2 is fixedly connected with an air extraction pump 69. The air inlet end of the air extraction pump 69 is fixedly communicated with a three-way reversing solenoid valve 610. The top air inlet end of the three-way reversing solenoid valve 610 is fixedly communicated with the bottom end of the hollow disc 68. The outer wall of the hollow forming inner mold 11 located inside the hollow disc 68 is provided with air outlet holes 611. The bottom end of the first air pipe 66 is fixedly connected with the upper surface of the hollow disc 68. The upper surface of the hollow disc 68 is provided with through holes, and the inner wall of the through holes is fixedly connected with a blanking mechanism 7. The blanking mechanism 7 includes a fixed pipe 71. The upper surface of the hollow disc 68 is provided with an installation through hole that matches the fixed pipe 71. The inner wall of the fixed pipe 71 is fixedly connected with a second electric hydraulic rod 72. The moving end of the second electric hydraulic rod 72 is fixedly connected with the lower surface of the bottom cylinder 13. This mechanism enables the oil-impregnated bearing powder metallurgy forming equipment to have the function of sucking air to reduce the porosity of metal powder materials, reduces the cycle of oil-impregnated bearing extrusion processing, and improves the efficiency of oil-impregnated bearing extrusion processing at the same time.

[0023] A driving mechanism 9 is fixedly connected to the outer wall of the bottom end of the bottom plate 2. The driving mechanism 9 includes a driving motor 91 fixedly connected to the bottom end of the bottom plate 2. The inner wall of the top end of the support platform 1 is connected to a rotating rod 92 through a rolling bearing. The bottom end of the rotating rod 92 is fixedly connected to the output end of the driving motor 91. The rod wall of the rotating rod 92 is fixedly sleeved with a first gear 93 and a second gear 94. The outer wall of the bottom end of the hollow forming outer mold 10 is fixedly sleeved with a third gear 95 meshing with the first gear 93. The outer wall of the bottom end of the hollow forming inner mold 11 is fixedly sleeved with a fourth gear 96 meshing with the second gear 94. This mechanism enables the powder metallurgy forming equipment for oil-impregnated bearings to have the function of preventing metal powder materials from adhering to the forming mold, avoiding the situation of local powder shedding on the surface of the formed oil-impregnated bearing, and reducing the surface roughness and porosity of the oil-impregnated bearing surface.

[0024] The rotating speeds of the inner wall of the hollow forming outer mold 10 and the outer wall of the hollow forming inner mold 11 are the same. By precisely controlling the tooth number ratios of the first gear 93 and the third gear 95, and the second gear 94 and the fourth gear 96, it can be ensured that the rotational linear speeds of the inner wall of the hollow forming outer mold 10 and the outer wall of the hollow forming inner mold 11 are the same, keeping the forming environment in the forming cavity 12 stable, and avoiding the disorder of the metal powder materials of the oil-impregnated bearing due to speed differences, thereby ensuring the quality of the extrusion processing of the oil-impregnated bearing.

[0025] The air outlet end of the air extraction pump 69 is fixedly communicated with an auxiliary mechanism 8. The auxiliary mechanism 8 includes a second air pipe 81 fixedly communicated with the air outlet end of the air extraction pump 69. A through hole is formed in the outer wall of the outer cover 62, and the hole wall of the through hole is fixedly connected with a metal cover 82. The outer wall of the metal cover 82 is in movable contact with the outer wall of the hollow forming outer mold 10. A semiconductor refrigeration sheet 83 is fixedly connected to the inner wall of the metal cover 82. A heat sink 84 is fixedly connected to the heat dissipation side surface of the semiconductor refrigeration sheet 83. The air outlet end of the second air pipe 81 is fixedly connected to the inner wall of the opening side of the metal cover 82. A metal mesh cylinder 85 is fixedly connected to the internal cavity of the hollow forming outer mold 10. This mechanism can enable the powder metallurgy forming equipment for oil-impregnated bearings to have the function of preventing high temperature during the forming of metal powder materials, and improving the ability to avoid local quality defects of the oil-impregnated bearing.

[0026] The first electro-hydraulic rod 41, the air extraction pump 69, the second electro-hydraulic rod 72, and the semiconductor refrigeration sheet 83 are all electrically connected to an external power supply through the control box 15. The three-way reversing solenoid valve 610 and the driving motor 91 are both electrically connected to the external power supply through the push switch 45. The above-mentioned electrified devices and electrical connections are all prior arts and will not be elaborated here.

[0027] The operating principle of the present invention is described as follows: Before a quantitative amount of metal powder material for the oil-impregnated bearing is fed into the forming cavity 12 composed of the hollow forming outer mold 10 and the hollow forming inner mold 11, the air pump 69 is started through the control box 15. The air pump 69 sucks the air inside the hollow disc 68 through the top air inlet of the three-way reversing solenoid valve 610, creating a negative pressure environment inside the hollow disc 68. Then, the hollow disc 68 in this negative pressure environment not only sucks the air inside the hollow forming inner mold 11 through the air outlet hole 611 but also sucks the air inside the hollow forming outer mold 10 through the first air pipe 66, the outer cover 62, and the air permeation holes 65. At this time, the hollow forming outer mold 10 sucks the air inside the forming cavity 12 through the first breathable ceramic block 63 to maintain pressure balance, and the hollow forming inner mold 11 sucks the air inside the forming cavity 12 through the second breathable ceramic block 64 to maintain pressure balance, thereby making the entire forming cavity 12 form a negative pressure environment; After the quantitative oil-impregnated bearing metal powder is fed into the forming cavity 12, the forming cavity 12 in the negative pressure environment will aspirate and compress the loose metal powder material, reducing the porosity of the metal powder material. This process enables the pressing cylinder 42 not to spend a large amount of time exhausting air during the extrusion process of the metal powder material, thereby effectively reducing the cycle of the extrusion processing of the metal powder material. At the same time, through the control box 15, the first electro-hydraulic rod 41 and the semiconductor refrigerating sheet 83 are controlled to start. The moving end of the first electro-hydraulic rod 41 pushes the pressing cylinder 42 downward. After the pressing cylinder 42 enters the forming cavity 12, the extrusion processing of the metal powder material is completed. This mechanism enables the oil-impregnated bearing powder metallurgy forming equipment to have the function of sucking air to reduce the porosity of the metal powder material, reduces the cycle of the oil-impregnated bearing extrusion processing, and improves the efficiency of the oil-impregnated bearing extrusion processing; While the metal powder material is being extruded and formed in the die cavity 12 by the pressing cylinder 42, the pressing plate 43 will press the push switch 45. Since the damping force of the damping telescopic rod 44 is greater than the pressing force of the push switch 45 button, after the pressing plate 43 contacts the push switch 45, the button of the push switch 45 will move downward first, causing the push switch 45 to conduct. After the push switch 45 is conducted, it controls the three-way directional solenoid valve 610 and the drive motor 91 to be powered on and start. The drive motor 91 drives the rotating rod 92 to rotate, the rotating rod 92 drives the first gear 93 and the second gear 94 to rotate, the first gear 93 drives the third gear 95 to rotate, the second gear 94 drives the fourth gear 96 to rotate, the third gear 95 drives the hollow forming outer mold 10 to rotate, and the fourth gear 96 drives the hollow forming inner mold 11 to rotate. By precisely controlling the tooth number ratio of the first gear 93 and the third gear 95, and the second gear 94 and the fourth gear 96, it can ensure that the rotational linear speeds of the inner wall of the hollow forming outer mold 10 and the outer wall of the hollow forming inner mold 11 are consistent, keeping the forming environment in the die cavity 12 stable, and preventing the metal powder material of the oil-impregnated bearing from being disordered due to speed differences, thereby ensuring the quality of the extrusion processing of the oil-impregnated bearing. During this process, the dynamic shear force generated by the rotation of the hollow forming inner mold 11 and the hollow forming outer mold 10 can effectively break the adhesion force between the powder and the mold wall. Specifically, after the hollow forming inner mold 11 and the hollow forming outer mold 10 rotate, the metal powder material in the die cavity 12 is extruded by the pressing cylinder 42 without rotating, and a tangential force will be generated at the contact surface between the metal powder material and the mold wall. This tangential force continuously acts on the powder particles, preventing them from tightly adhering to the mold wall. When the formed oil-impregnated bearing is demolded, due to the lack of adhesion force, there will be no powder peeling on its surface, thereby reducing the surface roughness and porosity of the oil-impregnated bearing and significantly reducing the scrap rate; After the oil-impregnated bearing is formed, the control box 15 is used to control the first electro-hydraulic rod 41 to drive the pressing cylinder 42 to move upward. After the first electro-hydraulic rod 41 retracts completely, the control box 15 is used to control the movable end of the second electro-hydraulic rod 72 to move upward. The second electro-hydraulic rod 72 pushes the bottom cylinder 13 upward, and the bottom cylinder 13 pushes the formed oil-impregnated bearing out of the die cavity 12, facilitating the material taking of the formed oil-impregnated bearing. The movable end of the second electro-hydraulic rod 72 remains extended for 5 seconds after being fully extended to ensure sufficient time for the material taking operation of the oil-impregnated bearing. After 5 seconds, the control box 15 controls the movable end of the second electro-hydraulic rod 72 to retract to the initial position, restoring the die cavity 12 to the ready state to prepare for the powder forming of the next oil-impregnated bearing. This mechanism enables the oil-impregnated bearing powder metallurgy forming equipment to have the function of preventing the metal powder material from adhering to the forming mold, avoiding the situation of local powder peeling on the surface of the formed oil-impregnated bearing, reducing the surface roughness and porosity of the oil-impregnated bearing, and not only improving the quality of the oil-impregnated bearing powder metallurgy forming, but also improving the qualification rate and reliability of the forming equipment processing; After the semiconductor refrigeration chip 83 is powered on, its refrigerating side cools down the metal cover 82. The low-temperature metal cover 82 can cool down the air in the outer cover 62 and the hollow forming outer mold 10. The hollow forming outer mold 10 further cools down the forming mold cavity 12. The air extracted by the air extraction pump 69 is transported to the metal cover 82 through the second air pipe 81, accelerating the air flow speed in the metal cover 82, enabling the heat dissipation side of the semiconductor refrigeration chip 83 to cool down rapidly, and at the same time ensuring the efficient refrigeration of the refrigerating side of the semiconductor refrigeration chip 83. When the push switch 45 is pressed to power on the three-way reversing solenoid valve 610, the three-way reversing solenoid valve 610 changes the air intake direction. The air extraction pump 69 sucks a large amount of air through the side air intake port of the three-way reversing solenoid valve 610. A large amount of air is transported to the metal cover 82, efficiently completing the heat dissipation work of the heat dissipation side of the semiconductor refrigeration chip 83, ensuring the refrigeration effect of the semiconductor refrigeration chip 83, further preventing the temperature of the forming mold cavity 12 from rising. In this way, when the oil-impregnated bearing metal powder material is subjected to extrusion processing friction, the local temperature will not rise sharply, avoiding the occurrence of local overheating or premature decomposition of the binder of the oil-impregnated bearing, and avoiding the generation of quality defects in the oil-impregnated bearing. When the pressing plate 43 moves upward, the button of the push switch 45 resets, the three-way reversing solenoid valve 610 and the drive motor 91 are powered off, and the air extraction pump 69 resumes intake from the top air intake end of the three-way reversing solenoid valve 610. This mechanism enables the oil-impregnated bearing powder metallurgy forming equipment to have the function of preventing high temperature during metal powder material forming, improving the ability to avoid local quality defects in the oil-impregnated bearing, further improving the quality of the extrusion processing of the oil-impregnated bearing, and improving the reliability of the use of the forming equipment.

[0028] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A molding device for powder metallurgy of oil-containing bearings, including a support table (1), characterized in that, The inner wall of the bottom end of the support table (1) is fixedly connected with a bottom plate (2). The upper surface of the support table (1) is fixedly connected with an L-shaped frame (3). A through hole is formed in the top end of the L-shaped frame (3), and the hole wall of the through hole is fixedly connected with an extrusion mechanism (4). A first counterbore is formed in the inner wall of the top end of the support table (1), and the hole wall of the first counterbore is fixedly connected with a first sealed bearing (5). The inner wall of the inner ring of the first sealed bearing (5) is fixedly connected with a hollow forming outer mold (10). A hollow forming inner mold (11) is arranged inside the hollow forming outer mold (10). The bottom end of the hollow forming inner mold (11) is connected to the upper surface of the bottom plate (2) through a rolling bearing. A forming mold cavity (12) is jointly arranged between the inner wall of the hollow forming outer mold (10) and the outer wall of the hollow forming inner mold (11). The outer wall of the hollow forming inner mold (11) is movably sleeved with a bottom cylinder (13). The outer wall of the top end of the bottom cylinder (13) is in movable sealing contact with the surface of the bottom end mold cavity of the forming mold cavity (12). The outer wall of the hollow forming outer mold (10) is fixedly sleeved with an air extraction mechanism (6). The outer wall of the bottom end of the bottom plate (2) is fixedly connected with a driving mechanism (9).

2. The molding equipment for oil-impregnated bearing powder metallurgy according to claim 1, wherein, The extrusion mechanism (4) includes a first electro-hydraulic rod (41) fixedly embedded in the top end of the support table (1). The moving end of the first electro-hydraulic rod (41) is fixedly connected with a pressing cylinder (42) that cooperates with the top of the forming mold cavity (12). A pressing plate (43) is fixedly connected to the outer wall of the pressing cylinder (42). A damping telescopic rod (44) is fixedly connected to the upper surface of the support table (1). The top end of the damping telescopic rod (44) is fixedly connected with a pressing switch (45). The pressing end of the pressing switch (45) is located below the pressing plate (43).

3. The oil-containing bearing powder metallurgy forming equipment according to claim 2, characterized in that: Two support rods (14) are fixedly connected to the inner wall of the L-shaped frame (3). The bottom ends of the support rods (14) are fixedly connected to the upper surface of the support table (1). A control box (15) is fixedly connected to the upper surface of the L-shaped frame (3).

4. The oil-containing bearing powder metallurgy forming equipment according to claim 3, characterized in that: The air extraction mechanism (6) includes a second sealing bearing (61) fixedly sleeved on the outer wall of the hollow forming outer mold (10). The outer wall of the outer ring of the second sealing bearing (61) is fixedly sleeved with an outer cover (62). The top end of the outer cover (62) is fixedly connected to the inner wall of the top end of the support table (1). A plurality of first air intake sink holes are formed in the inner wall of the hollow forming outer mold (10), and a first breathable ceramic block (63) is fixedly connected to the hole wall of the first air intake sink hole. A plurality of second air intake sink holes are formed in the outer wall of the hollow forming inner mold (11), and a second breathable ceramic block (64) is fixedly connected to the hole wall of the second air intake sink hole. Breathable holes (65) are formed in the outer wall of the hollow forming outer mold (10) inside the outer cover (62). The outer wall of the outer cover (62) is fixedly communicated with a first air pipe (66). Two third sealing bearings (67) are fixedly sleeved on the outer wall of the hollow forming inner mold (11). The outer walls of the outer rings of the two third sealing bearings (67) are jointly fixedly sleeved with a hollow disc (68). The outer wall of the hollow disc (68) is fixedly connected to the inner wall of the support table (1). An air extraction pump (69) is fixedly connected to the upper surface of the bottom plate (2). The air intake end of the air extraction pump (69) is fixedly communicated with a three-way reversing solenoid valve (610). The top air intake end of the three-way reversing solenoid valve (610) is fixedly communicated with the bottom end of the hollow disc (68). Air outlet holes (611) are formed in the outer wall of the hollow forming inner mold (11) inside the hollow disc (68). The bottom end of the first air pipe (66) is fixedly communicated with the upper surface of the hollow disc (68). A through hole is formed in the upper surface of the hollow disc (68), and a blanking mechanism (7) is fixedly connected to the hole wall of the through hole. The air outlet end of the air extraction pump (69) is fixedly communicated with an auxiliary mechanism (8).

5. The forming device for oil-impregnated bearing powder metallurgy according to claim 4, characterized in that, The blanking mechanism (7) includes a fixed pipe (71). An installation through hole matching the fixed pipe (71) is formed through the upper surface of the hollow disc (68). A second electric hydraulic rod (72) is fixedly connected to the inner wall of the fixed pipe (71). The moving end of the second electric hydraulic rod (72) is fixedly connected to the lower surface of the bottom cylinder (13).

6. The molding equipment for oil-impregnated bearing powder metallurgy according to claim 5, characterized in that, The auxiliary mechanism (8) includes a second air pipe (81) fixedly communicated with the air outlet end of the air extraction pump (69). A through hole is formed in the outer wall of the outer cover (62), and a metal cover (82) is fixedly connected to the hole wall of the through hole. The outer wall of the metal cover (82) is in movable contact with the outer wall of the hollow forming outer mold (10). A semiconductor refrigeration sheet (83) is fixedly connected to the inner wall of the metal cover (82). A heat sink (84) is fixedly connected to the heat dissipation side surface of the semiconductor refrigeration sheet (83). The air outlet end of the second air pipe (81) is fixedly connected to the inner wall of the opening side of the metal cover (82). A metal mesh cylinder (85) is fixedly connected to the inner cavity of the hollow forming outer mold (10).

7. The forming device for powder metallurgy of an oil-impregnated bearing according to claim 6, characterized in that, The driving mechanism (9) includes a driving motor (91) fixedly connected to the bottom end of the bottom plate (2). The inner wall of the top end of the support table (1) is connected with a rotating rod (92) through a rolling bearing. The bottom end of the rotating rod (92) is fixedly connected to the output end of the driving motor (91). The rod wall of the rotating rod (92) is fixedly sleeved with a first gear (93) and a second gear (94). The outer wall of the bottom end of the hollow forming outer mold (10) is fixedly sleeved with a third gear (95) meshing with the first gear (93). The outer wall of the bottom end of the hollow forming inner mold (11) is fixedly sleeved with a fourth gear (96) meshing with the second gear (94).

8. The molding equipment for oil-impregnated bearing powder metallurgy according to claim 7, characterized in that, The rotating speeds of the inner wall of the hollow forming outer mold (10) and the outer wall of the hollow forming inner mold (11) are the same.

9. A method of using a molding device for powder metallurgy of an oil-impregnated bearing as described in claim 8, characterized in that, The method includes the following steps: Step S1: Before the metal powder material of the oil-impregnated bearing in a fixed quantity is fed into the forming cavity (12) composed of the hollow forming outer mold (10) and the hollow forming inner mold (11), a negative pressure environment is formed in the forming cavity (12) through the air extraction mechanism (6). Step S2: After the fixed quantity of oil-impregnated bearing metal powder is fed into the forming cavity (12), the forming cavity (12) in the negative pressure environment will extract and compress the loose metal powder material. Step S3: Then, the first electro-hydraulic rod (41) and the semiconductor refrigerating sheet (83) are controlled to start through the control box (15). The moving end of the first electro-hydraulic rod (41) pushes the pressing cylinder (42) to move downward. After the pressing cylinder (42) enters the forming cavity (12), the processing of extruding the metal powder material is completed. Step S4: After the pressing cylinder (42) drives the pressing plate (43) to move downward, the pressing switch (45) is pressed. The pressing switch controls the three-way directional solenoid valve (610) and the driving motor (91) to start. The driving motor (91) drives the inner wall of the hollow forming outer mold (10) and the outer wall of the hollow forming inner mold (11) to have the same rotational linear speed through the driving mechanism (9). Step S5: While step S4 is being carried out, the semiconductor refrigerating sheet (83) is energized to cool the metal cover (82). The forming cavity (12) can be cooled through the low-temperature metal cover (82). Moreover, the air discharged from the air outlet end of the air extraction pump (69) can maintain the refrigerating effect of the semiconductor refrigerating sheet (83). When the pressing switch (45) controls the three-way directional solenoid valve (610) to be energized, the air extraction pump (69) conveys a large amount of air into the metal cover (82) of the auxiliary mechanism (8) and assists in the heat dissipation work on the heat dissipation side of the semiconductor refrigerating sheet (83). Step S6: Finally, the oil-impregnated bearing powder metallurgy forming equipment controls the extrusion mechanism (4) and the ejecting mechanism (7) through the control box (15) to eject the qualified formed oil-impregnated bearing from the forming cavity (12).

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