Plasticizing injection molding equipment of exhaust type injection molding machine

Abstract

The invention discloses plasticizing injection molding equipment of an exhaust type injection molding machine, which belongs to the technical field of injection molding and comprises a shell, a melting cavity enclosed by the shell and an injection bin arranged on one side of the shell and communicated with an inner cavity of the shell, and a control bin is arranged at the top of the outer side of the shell. A heating screw which is driven by the control bin and controls heating is vertically arranged in the melting cavity, and a hopper communicated with the melting cavity is arranged above the shell. The plasticizing injection molding equipment of the exhaust type injection molding machine is high in exhaust efficiency, most volatile gas is condensed and recycled, and the plasticizing injection molding equipment is environmentally friendly and low in operation threshold.

Description

Technical Field

[0001] The invention relates to the technical field of injection molding, and in particular to plasticizing injection molding equipment of an exhaust type injection molding machine. Background Art

[0002] For special plastic materials such as biodegradable plastics, engineering plastics PA, PC, ABS, AS, PCTG, PET, PBT and other high-humidity plastics, they need to be dehumidified and dried before production. During the plasticization process of plastics, it is difficult to completely treat small molecular gases, moisture, and volatiles through drying and dehumidification equipment; the dehumidification and drying process has high temperature, long time, low efficiency, and low product qualification rate. In addition, some injection molding products with low requirements have a high proportion of recycled materials. These recycled materials are high-humidity materials and are prone to excessive degradation. During the injection molding process, small molecular gases are easily generated, the production process is not smooth, and the gas is stored in the product, making it difficult to meet the quality standards. The screw of the existing exhaust injection molding machine adopts a reciprocating exhaust screw, which is divided into two stages, front and back, while the screw of the ordinary injection molding machine has only one stage. The first stage has a feeding section, a compression section and a metering section; the second stage has a decompression section, a compression section and a metering section. After the material enters the first stage screw from the feeding port, it is conveyed by the first feeding section. The plasticized material in the compression section has been plasticized into a viscoelastic state. Then, the melt is thinned by the over-shear element at the end of the first stage. The gas adheres to the surface of the melt layer and enters the decompression section of the second stage screw. Because the screw groove of the decompression section suddenly becomes deeper and the volume increases, an exhaust hole is opened on the barrel of the decompression section. The hole is often connected to the atmosphere or to the vacuum pump tank. The melt pressure in the screw groove of the decompression section suddenly drops to zero or negative pressure. The compressed water vapor and various gasified volatile substances in the polymer melt burst and separate from the melt and are discharged from the exhaust port. However, the gas discharged by this type of exhaust injection molding machine is mostly discharged directly to the atmosphere, which increases the health risk of personnel operation and the difficulty of generation and environmental protection. If materials such as activated carbon are added to the exhaust port for adsorption, it is easy to block the exhaust port, which reduces the efficiency of extrusion and exhaust. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the present invention proposes a plasticizing injection molding device for a venting type injection molding machine. The technical solution of the present invention is as follows:

[0004] A plasticizing injection molding device of an exhaust type injection molding machine, comprising a shell, a melting cavity surrounded by the shell, and an injection bin arranged on one side of the shell and connected to the inner cavity of the shell; a control bin is arranged on the top of the outer side of the shell; a heating screw driven and controlled by the control bin is vertically arranged in the melting cavity; a hopper connected to the melting cavity is arranged above the shell;

[0005] An exhaust passage which is respectively connected with the melting chamber and the outside of the shell is spirally arranged from top to bottom in the shell.

[0006] Furthermore, the exhaust duct located above the melting chamber is provided with multiple air inlets connected to the melting chamber; an exhaust port connected to the exhaust duct is provided below the shell; and a closing plate controlled to rotate by the control chamber is provided in the melting chamber and close to the inner wall of the shell.

[0007] Furthermore, the closing plate is provided with a plurality of through holes corresponding to the air inlets respectively and penetrating the air inlets; the distance between the air inlets is not less than the diameter of the air inlet;

[0008] The closing plate is provided with a feed port communicating with the hopper; when the closing plate is rotated until the feed port is communicated with the hopper, each through port is staggered with each air inlet, and the closing plate covers each air inlet.

[0009] Furthermore, the exhaust ducts include a plurality of exhaust ducts; an air collecting duct is provided inside the lower part of the shell to collect the exhaust ducts and communicate with the exhaust port; the exhaust ducts are closely attached to the outer wall of the shell and do not intersect with each other.

[0010] Furthermore, the melting chamber includes an upper first-stage plasticizing section and a lower second-stage plasticizing section; the air inlet is opened on the exhaust duct at the position of the first-stage plasticizing section;

[0011] The heating screw comprises a first-stage screw located in the first-stage plasticizing section and a second-stage screw located in the second-stage plasticizing section; the first-stage screw and the second-stage screw are matched with the diameters of the first-stage plasticizing section and the second-stage plasticizing section respectively.

[0012] Furthermore, the first-stage screw is provided with an upward and downward communication port.

[0013] Furthermore, an electromagnetic plate connected to the control compartment is provided from top to bottom in the closed plate; a receiving groove with a diameter not less than that of the AC port is provided around the AC port in the first-stage screw at the position of the AC port; an elastic member is provided in the receiving groove, with both ends respectively fixed to the inner wall of the receiving groove, and a magnetically conductive cover plate covering the AC port is fixed on the elastic member.

[0014] Furthermore, a discharge port communicating with the filling bin is provided at the bottom of the shell body at the position of the filling bin; and a nozzle is provided at one end of the filling bin away from the discharge port.

[0015] Furthermore, a lifting plate that moves up and down is horizontally provided in the inner cavity of the filling bin at the upper end of the discharge port; the lifting plate divides the inner cavity above the filling bin into a condensation chamber; and an escape port that connects the exhaust duct with the condensation chamber is provided on the outer wall of the shell at the position of the condensation chamber.

[0016] Furthermore, a plurality of slide rails connected to the lifting plate are provided on the wall of the filling bin on the peripheral side of the lifting plate, and the lowermost end of each slide rail is higher than the upper end of the discharge port.

[0017] Based on the above technical solution, the technical effects that can be achieved by the present invention are:

[0018] 1. The exhaust duct of the present invention guides the exhausted volatile gas to perform heat exchange on the outer wall of the shell, and the volatile gas is discharged along the exhaust duct after being cooled and liquefied, so that the volatile gas can be collected during the exhaust injection molding process.

[0019] 2. The main body of the equipment of the present invention is vertically arranged. During the downward melting and compacting process, the gas escaping from the material moves upward and gathers. Compared with the horizontally arranged main body, the gas can be separated from the material more conveniently, avoiding the problem that the exhaust port is too small due to the horizontal arrangement, and the screw is prone to mixing the gas into the material for the second time during the material transportation process.

[0020] 3. The closing plate of the present invention can realize the opening and closing of the air inlet and the hopper, preventing the volatile gas from escaping directly from the hopper, and also preventing the molten material from overflowing into the exhaust duct before leaving the first-stage plasticizing section, causing blockage.

[0021] 4. The AC port of the present invention can quickly reduce the pressure and promote the escape of volatile gases below. After the material enters the second-stage plasticizing section, the residual volatile gases in the material during the transportation process can still escape upward from the AC port of the present invention, reducing the probability of gas mixing into the material for the second time.

[0022] 5. In the present invention, when the material is plasticized to the end and is about to be injected, the volatile gas is basically evaporated, and the volatile gas entering the condensation chamber from the escape port begins to liquefy and the volume is reduced, which prompts the lifting plate to rise, and the inner cavity pressure of the injection bin below is reduced, which generates suction for the plasticized material, and the auxiliary material enters the injection bin from the discharge port to reduce resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the front structural view of the plasticizing injection molding equipment of the exhaust type injection molding machine of the present invention.

[0024] Figure 2 It is a schematic structural diagram of the exhaust duct of the plasticizing injection molding equipment of the exhaust type injection molding machine of the present invention.

[0025] Figure 3 It is an AA cross-sectional view of the plasticizing injection molding device of the exhaust type injection molding machine of the present invention.

[0026] Figure 4 It is a BB cross-sectional view of the plasticizing injection molding device of the exhaust type injection molding machine of the present invention.

[0027] Figure 5It is an enlarged view of C of the plasticizing injection molding device of the exhaust type injection molding machine of the present invention.

[0028] Figure 6 It is a DD cross-sectional view of the plasticizing injection molding device of the exhaust type injection molding machine of the present invention.

[0029] In the figure: 1-shell; 11-control chamber; 12-hopper; 13-feeding port; 14-exhaust port; 2-melting chamber; 21-first-stage screw; 22-closing plate; 221-through port; 222-exhaust duct; 223-air inlet; 224-air collecting duct; 225-exchange port; 226-accommodating groove; 227-elastic member; 228-cover plate; 26-second-stage screw; 3-filling chamber; 31-discharging port; 32-condensing chamber; 33-slide rail; 34-lifting plate; 35-sealing ring; 36-nozzle; 37-escape port. DETAILED DESCRIPTION

[0030] The content of the present invention is further described below in conjunction with the drawings of the specification. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0031] like Figure 1 and Figure 3 As shown, this embodiment provides a plasticizing injection molding device of a venting injection molding machine, including a shell 1, a melting chamber 2 surrounded by the shell 1, and an injection bin 3 provided on one side of the shell 1 and connected to the inner chamber of the shell 1. A control bin 11 is provided on the top of the outer side of the shell 1. A heating screw driven and heated by the control bin 11 is vertically provided in the melting chamber 2. A hopper 12 connected to the melting chamber 2 is provided above the shell 1. An exhaust channel 222 connected to the melting chamber 2 and the outside of the shell 1 is spirally provided from top to bottom in the shell 1.

[0032] Preferably, the exhaust channel 222 located above the melting chamber 2 is provided with a plurality of air inlets 223 connected to the melting chamber 2. An exhaust port 14 connected to the exhaust channel 222 is provided below the shell 1. A closing plate 22 controlled to rotate by the control chamber 11 is provided in the melting chamber 2 and close to the inner wall of the shell 1.

[0033] Preferably, the closing plate 22 is provided with a plurality of through holes 221 corresponding to the air inlets 223 and communicating with the air inlets 223; the distance between the air inlets 223 is not less than the diameter of the air inlet 223. The closing plate 22 is provided with a feed port 13 communicating with the hopper 12; when the closing plate 22 is rotated until the feed port 13 communicates with the hopper 12, the through holes 221 are staggered with the air inlets 223, and the closing plate 22 covers the air inlets 223.

[0034] Preferably, Figure 2As shown, there are multiple exhaust ducts 222. An air collecting duct 224 is provided at the lower interior of the shell 1 to collect the exhaust ducts 222 and communicate with the exhaust port 14. The exhaust ducts 222 are close to the outer wall of the shell 1 and do not intersect with each other.

[0035] Preferably, Figures 4 to 6 As shown, the melting chamber 2 includes a first-stage plasticizing section at the top and a second-stage plasticizing section 25 at the bottom. The air inlet 25 is opened on the exhaust duct 222 at the position of the first-stage plasticizing section. The heating screw includes a first-stage screw 21 located in the first-stage plasticizing section and a second-stage screw 26 located in the second-stage plasticizing section 25. The first-stage screw 21 and the second-stage screw 25 are matched with the diameters of the first-stage plasticizing section and the second-stage plasticizing section 25, respectively. Preferably, the first-stage screw 21 is provided with an exchange port 225 that passes through from top to bottom.

[0036] Preferably, an electromagnetic plate connected to the control compartment 11 is provided from top to bottom in the closing plate 22. A receiving groove 226 having a diameter not less than that of the AC port 225 is provided around the AC port 225 in the first-stage screw 25 at the position of the AC port 225. An elastic member 227 having two ends respectively fixed to the inner wall of the receiving groove 226 is provided in the receiving groove 226, and a magnetically conductive cover sheet 228 covering the AC port 225 is fixed on the elastic member 227. Preferably, the cover sheet 228 forms a dynamic seal with the inner wall of the receiving groove 226.

[0037] Preferably, Figure 1 and Figure 3 As shown, the bottom of the housing 1 at the position of the injection bin 3 is provided with a discharge port 31 which is in communication with the injection bin 3. A nozzle 36 is provided at one end of the injection bin 3 away from the discharge port 31.

[0038] Preferably, a lifting plate 34 that moves up and down is horizontally provided in the inner cavity of the injection bin 3 at the upper end of the discharge port 31. The lifting plate 34 divides the inner cavity above the injection bin 3 into a condensation chamber 32. An escape port 37 that connects the exhaust duct 222 with the condensation chamber 32 is provided on the outer wall of the shell 1 at the position of the condensation chamber 32. Preferably, a sealing ring 35 that fits with the inner wall of the injection bin 3 is provided on the outer periphery of the lifting plate 34.

[0039] Preferably, a plurality of slide rails 33 connected to the lifting plate 34 are provided on the wall of the filling bin 3 on the peripheral side of the lifting plate 34 , and the lowermost end of each slide rail 33 is higher than the upper end of the discharge port 31 .

[0040] Based on the above structure, the plasticizing injection molding equipment of the exhaust type injection molding machine of the present invention, the motor in the control chamber 11 and the reduction box assembly control the rotation of the heating screw and the closing plate 22. After the material enters the melting chamber 2 from the hopper 12, the closing plate 22 rotates to close the feed port 13 and the air inlet 223. The heating screw heats and melts the material and transports it downward during the rotation. After the material is transported to the second-stage screw 26 through the first-stage screw 21, the closing plate 22 continues to rotate, so that the through port 221 is connected with the air inlet 223, and the feed port 13 is kept closed. The pressure in the melting chamber 2 drops rapidly, and the generated volatile gas enters the exhaust duct 222 from the air inlet 223, and tends to liquefy due to the rapid decrease in pressure. In addition, the gas entering the exhaust duct 222 forms a long heat transfer with the outer wall of the shell with a lower temperature in the exhaust duct 222 which has a long path due to the spiral, and further continues to liquefy until it reaches the gas collecting duct 224 at the bottom, and is collected and processed from the exhaust port 14 to prevent the volatile gas from being directly discharged into the air.

[0041] When the air inlet 223 is opened, the electromagnetic plate in the closing plate 22 generates magnetic force to attract the cover plate 228, causing the elastic member 227 to deform, and the cover plate 228 leaves the AC port 225, further reducing the air pressure at the second-stage screw 26, causing the gas in the material to escape, quickly flow into the first-stage screw 21 from the AC port 225, and enter the exhaust duct 222, thereby achieving full discharge of the gas.

[0042] Part of the gas enters the condensation chamber 32 from the escape port 37. When the material reaches the discharge port 31, most of the gas in the material has evaporated, and the condensation chamber 32 loses continuous gas exchange. Part of the gas stored in the chamber enters the exhaust duct 222, and part of the gas begins to liquefy due to heat transfer with the outside world. The air pressure in the condensation chamber decreases, the lifting plate 34 rises, and the pressure in the injection bin 3 decreases, forming suction on the material at the discharge port 31, prompting the material to enter the injection bin 3, reducing the resistance to material transfer, and the heating screw continues to rotate to push the material for injection.

[0043] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A plasticizing injection molding device of a venting injection molding machine, characterized in that: The invention comprises a shell (1), a melting chamber (2) surrounded by the shell (1), and a material injection bin (3) arranged at one side of the shell (1) and connected to the inner chamber of the shell (1); a control bin (11) is arranged at the top of the outer side of the shell (1); a heating screw driven and controlled by the control bin (11) is arranged vertically in the melting chamber (2); a material hopper (12) connected to the melting chamber (2) is arranged above the shell (1); An exhaust passage (222) is spirally provided from top to bottom in the shell (1) and is connected to the melting chamber (2) and the outside of the shell (1) respectively.

2. The plasticizing injection molding equipment of the exhaust type injection molding machine according to claim 1, characterized in that: An exhaust passage (222) located above the melting chamber (2) is provided with a plurality of air inlets (223) in communication with the melting chamber (2); an exhaust port (14) in communication with the exhaust passage (222) is provided below the shell (1); and a closing plate (22) is provided in the melting chamber (2) and in close contact with the inner wall of the shell (1), the closing plate being controlled to rotate by the control chamber (11).

3. The plasticizing injection molding device of the exhaust type injection molding machine according to claim 2, characterized in that: The closing plate (22) is provided with a plurality of through openings (221) corresponding to the air inlets (223) respectively and communicating with the air inlets (223); the distance between the air inlets (223) is not less than the diameter of the air inlet (223); The closing plate (22) is provided with a feed port (13) that is in communication with the hopper (12); when the closing plate (22) is rotated until the feed port (13) is in communication with the hopper (12), each through port (221) and each air inlet (223) are staggered, and the closing plate (22) covers each air inlet (223).

4. The plasticizing injection molding device of the exhaust type injection molding machine according to claim 2, characterized in that: The exhaust ducts (222) include a plurality of exhaust ducts; an air collecting duct (224) is provided at the bottom of the shell (1) to collect the exhaust ducts (222) and communicate with the exhaust port (14); the exhaust ducts (222) are closely attached to the outer wall of the shell (1) and do not intersect with each other.

5. The plasticizing injection molding device of the exhaust type injection molding machine according to claim 2, characterized in that: The melting chamber (2) comprises an upper first-stage plasticizing section and a lower second-stage plasticizing section (25); the air inlet (25) is opened on the exhaust passage (222) at the position of the first-stage plasticizing section; The heating screw comprises a first-stage screw (21) located in a first-stage plasticizing section and a second-stage screw (26) located in a second-stage plasticizing section (25); the first-stage screw (21) and the second-stage screw (25) are matched with the diameters of the first-stage plasticizing section and the second-stage plasticizing section (25), respectively.

6. The plasticizing injection molding device of the exhaust type injection molding machine according to claim 5, characterized in that: The first-stage screw (21) is provided with a communication port (225) that passes through from top to bottom.

7. The plasticizing injection molding device of the exhaust type injection molding machine according to claim 6, characterized in that: An electromagnetic plate connected to the control chamber (11) is arranged from top to bottom in the closing plate (22); a receiving groove (226) having a diameter not less than that of the AC port (225) is arranged in the first-stage screw rod (25) at the position of the AC port (225) around the AC port (225); an elastic member (227) having two ends respectively fixed to the inner wall of the receiving groove (226) is arranged in the receiving groove (226); a magnetically conductive cover plate (228) covering the AC port (225) is fixed on the elastic member (227).

8. The plasticizing injection molding device of the exhaust type injection molding machine according to claim 1, characterized in that: A discharge port (31) which is in communication with the injection bin (3) is provided at the bottom of the shell (1) at the position of the injection bin (3); and a nozzle (36) is provided at one end of the injection bin (3) away from the discharge port (31).

9. The plasticizing injection molding device of the exhaust type injection molding machine according to claim 8, characterized in that: A lifting plate (34) that moves up and down is horizontally provided in the inner cavity of the injection bin (3) at the upper end of the discharge port (31); the lifting plate (34) divides the inner cavity above the injection bin (3) into a condensation cavity (32); and an escape port (37) that connects the exhaust duct (222) with the condensation cavity (32) is provided on the outer wall of the shell (1) at the position of the condensation cavity (32).

10. The plasticizing injection molding device of the exhaust type injection molding machine according to claim 9, characterized in that: A plurality of slide rails (33) connected to the lifting plate (34) are provided on the wall of the material injection bin (3) on the peripheral side of the lifting plate (34), and the lowermost end of each slide rail (33) is higher than the upper end of the material discharge port (31).

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