Vacuum feeding mechanism for injection molding machine

Abstract

The utility model discloses a vacuum feeding mechanism for an injection molding machine, which comprises a vacuum pump, a vacuum orifice of the vacuum pump is communicated with a feeding drying cylinder through an exhaust pipe, the feeding drying cylinder is communicated with a material cylinder through a material suction pipe, a funnel-shaped blanking hopper is arranged in the feeding drying cylinder, and the material cylinder is communicated with a material cylinder through a material suction pipe. The interior of the feeding and drying cylinder is divided into a feeding and drying cavity and a discharging cavity which are arranged up and down through the discharging hopper. The top of the feeding drying cavity is provided with an air exhaust opening communicating with the air exhaust pipe, the discharging end of the material suction pipe penetrates into the feeding drying cavity from the side wall of the feeding drying cavity, and a material blocking net plate located above the discharging end of the material suction pipe is arranged in the feeding drying cavity. The side wall of the discharging hopper communicates with an air pipe arranged on the outer wall of the feeding drying barrel, the outer end of the air pipe is connected with an induced draft fan, a filter screen plate is arranged at an air outlet of the induced draft fan, and a plurality of electric heating wires located below the filter screen plate are arranged in the air pipe in the flowing direction of induced air. The feeding device is good in feeding effect, and the quality of injection molding finished products can be guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of feeding mechanisms, in particular to a vacuum feeding mechanism for an injection molding machine. Background Art

[0002] Injection molding machines are the main molding equipment that uses plastic molding molds to make plastic products of various shapes from thermoplastics or thermosetting plastics. The work of an injection molding machine mainly includes four processes: loading, heating, melting, and injection.

[0003] Existing injection molding machines usually use vacuum feeding mechanisms for feeding. Although most vacuum feeding mechanisms can meet the basic requirements of vacuum feeding, they still have at least the following shortcomings in actual use: First, during the vacuum feeding process, the drying effect of the injection molded particles cannot be guaranteed, thereby affecting the quality of the subsequent injection molded products; Second, the injection molded particles are prone to enter the exhaust pipe, thereby affecting the feeding. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a vacuum feeding mechanism for an injection molding machine to solve the problems raised in the background technology.

[0005] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows.

[0006] A vacuum feeding mechanism for an injection molding machine comprises a vacuum pump, wherein the vacuum pump's vacuum port is connected to a feeding drying cylinder with a funnel-shaped bottom through an exhaust pipe, and the feeding drying cylinder is connected to a barrel containing injection molding particles through a suction pipe, wherein a funnel-shaped lower hopper is provided inside the feeding drying cylinder, and the lower hopper divides the interior of the feeding drying cylinder into a feeding drying chamber and a discharging chamber arranged upper and lower; an exhaust port connected to the exhaust pipe is provided on the top of the feeding drying chamber, and the discharging end of the suction pipe is discharged from the bottom of the feeding drying chamber The side wall penetrates into the feeding and drying chamber, and the interior of the feeding and drying chamber is provided with a material blocking mesh plate located above the discharge end of the suction pipe for blocking the injection molding particles from entering the exhaust port; the side wall of the lower hopper is connected to an air duct arranged on the outer wall of the feeding and drying cylinder, and the outer end of the air duct is connected to an induced draft fan for drawing air into the feeding and drying chamber, and the air outlet of the induced draft fan is provided with a filter mesh plate for filtering the induced air, and a number of electric heating wires are provided in the air duct along the flow direction of the induced air, located below the filter mesh plate, for heating the induced air.

[0007] Preferably, two annular plates with through holes are horizontally arranged inside the loading and drying chamber, which are spaced apart up and down and located above the discharge end of the suction pipe; the material blocking mesh plate is arranged between the two annular plates and connected to the two annular plates through a set spring, and the material blocking mesh plate is also provided with a vibration motor for clearing the injection molded particles on the material blocking mesh plate.

[0008] Preferably, a PLC controller is provided on the outer side wall of the feeding drying cylinder, and the output end of the PLC controller is respectively connected to the controlled ends of the vacuum pump, the induced draft fan, the electric heating wire and the vibration motor.

[0009] Preferably, a second solenoid valve is provided on the exhaust port; a first material level sensor and a humidity sensor are provided inside the loading and drying chamber, and a first solenoid valve is provided on the lower hopper; an exhaust port is provided on the top of the loading and drying chamber, a third solenoid valve is provided on the exhaust port, and a fourth solenoid valve is provided on the air outlet of the air duct; a second material level sensor is provided inside the discharging chamber, a discharging port connected to the discharging chamber and used to connect to the feed port of the injection molding machine is provided at the bottom of the loading and drying cylinder, and a fifth solenoid valve is provided on the discharging port; the input end of the PLC controller is respectively connected to the output ends of the first material level sensor, the second material level sensor and the humidity sensor, and the output end of the PLC controller is respectively connected to the controlled ends of the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve and the fifth solenoid valve.

[0010] Preferably, the side wall of the discharge port is inclined downward to provide a return port located above the barrel for returning the remaining material in the loading drying barrel to the barrel, and a sixth solenoid valve is provided on the return port, and the controlled end of the sixth solenoid valve is connected to the output end of the PLC controller.

[0011] Preferably, a wide-mouthed suction hopper is provided at the feeding end of the suction pipe located in the barrel.

[0012] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is as follows.

[0013] The utility model can realize continuous feeding of the injection molding machine by means of the provided vacuum pump, feeding drying cylinder and material cylinder; can prevent the material from entering the exhaust pipe by means of the provided material blocking mesh plate and vibration motor, thereby ensuring the feeding effect; can ensure the material drying effect by means of the provided air duct, induced draft fan, filter mesh plate and electric heating wire, and can also filter the induced draft, thereby ensuring the quality of the injection molded product. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural diagram of the present utility model.

[0015] Among them: 1. Vacuum pump, 2. Feed drying cylinder, 21. Feed drying chamber, 22. Discharge chamber, 3. Lower hopper, 4. Ring plate, 5. Spring, 6. Baffle plate, 7. Vibration motor, 8. Suction pipe, 9. Suction hopper, 10. Cylinder, 11. Air duct, 12. Induced draft fan, 13. Filter plate, 14. Electric heating wire, 15. Air extraction port, 16. Exhaust port, 17. Discharge port, 18. Return port, 19. PLC controller. DETAILED DESCRIPTION

[0016] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0017] A vacuum feeding mechanism for an injection molding machine, combined with Figure 1 As shown, it includes a vacuum pump 1, a loading drying cylinder 2 and a barrel 10, wherein the vacuum port of the vacuum pump 1 is connected to the loading drying cylinder 2 through an exhaust pipe; the loading drying cylinder 2 is connected to the barrel 10 through a suction pipe 8, and the barrel 10 contains injection molding particles.

[0018] The bottom of the loading drying cylinder 2 is funnel-shaped and is provided with a discharge port 17, which is used to connect to the feed port of the injection molding machine; a lower hopper 3 is provided inside the loading drying cylinder 2, and the lower hopper 3 is also funnel-shaped, and divides the interior of the loading drying cylinder 2 into a loading drying chamber 21 and a discharge chamber 22 arranged upper and lower, and the discharge chamber 22 is connected to the discharge port 17.

[0019] The top of the loading and drying chamber 21 is provided with an air extraction port 15, which is connected to an air extraction pipe, thereby connecting the loading and drying chamber 21 to the vacuum pump 1. The discharge end of the suction pipe 8 penetrates the loading and drying chamber 21 through the side wall, thereby connecting the loading and drying chamber 21 to the barrel 10. The feed end of the suction pipe 8 is located in the barrel 10 and is equipped with a suction hopper 9. The suction hopper 9 has a wide mouth to facilitate suction. When the vacuum pump 1 is operating, it evacuates the air in the loading and drying chamber 21, creating a certain negative pressure within the chamber. The injection molding particles in the barrel 10 are forced through the suction pipe 8 and drawn into the loading and drying chamber 21.

[0020] A blocking mesh plate 6 is provided inside the feeding and drying chamber 21 and is located above the discharge end of the suction pipe 8. The blocking mesh plate 6 is used to block the injection molding particles from entering the exhaust port 15, thereby preventing the injection molding particles from entering the exhaust pipe.

[0021] Specifically, two ring plates 4 with through holes are horizontally arranged inside the feeding and drying chamber 21. The two ring plates 4 are spaced apart and located above the discharge end of the suction pipe 8. A retaining mesh plate 6 is arranged between the two ring plates 4 and connected to the two ring plates 4 by a spring 5. A vibration motor 7 is also provided on the retaining mesh plate 6. When the vacuum pump 1 is working, the injection molded particles entering the barrel 10 will fall down under the obstruction of the retaining mesh plate 6 to avoid entering the exhaust port 15; when some injection molded particles remain on the retaining mesh plate 6, the vibration motor 7 is started, and the retaining mesh plate 6 will vibrate under the action of the vibration motor 7 and the spring 5, thereby shaking off the remaining injection molded particles and achieving the removal of the injection molded particles on the retaining mesh plate 6.

[0022] The side wall of the lower hopper 3 is connected to an air duct 11, which is arranged on the outer wall of the loading drying cylinder 2. The outer end of the air duct 11 is connected to an induced draft fan 12 via a flange. The induced draft fan 12 is used to draw air into the upper drying chamber 21. The air outlet of the induced draft fan 12 is provided with a filter screen 13, which is used to filter impurities and dust in the induced air to prevent contamination of the injection molded particles. Several electric heating wires 14 are arranged in the air duct 11 along the flow direction of the induced air. The electric heating wires 14 are located below the filter screen 13. The electric heating wires 14 are used to heat the induced air. The heated induced air enters the loading drying chamber 21, thereby drying the injection molded particles in the loading drying chamber 21. An exhaust port 16 is provided at the top of the loading drying chamber 21. The hot air dries the injection molded particles and is discharged through the exhaust port 16.

[0023] In order to realize the alternating loading and drying in the loading and drying chamber 21 so that the loading and drying processes do not affect each other, a second solenoid valve is provided on the exhaust port 15; a first material level sensor and a humidity sensor are provided inside the loading and drying chamber 21, and a first solenoid valve is provided on the lower hopper 3; a third solenoid valve is provided on the exhaust port 16, and a fourth solenoid valve is provided at the air outlet of the air duct 11; a second material level sensor is provided inside the discharge chamber 22, and a fifth solenoid valve is provided on the discharge port 17.

[0024] When loading, the second solenoid valve provided on the exhaust port 15 is opened, the first solenoid valve provided on the lower hopper 3, the third solenoid valve provided on the exhaust port 16 and the fourth solenoid valve provided on the air outlet of the air duct 11 are closed, and the vacuum pump 1 is started to evacuate the loading and drying chamber 21 to load the material; when the value monitored by the first material level sensor reaches the set material value, the vacuum pump 1 is turned off to complete the loading.

[0025] During drying, the second solenoid valve provided on the exhaust port 15 and the first solenoid valve provided on the lower hopper 3 are closed, the third solenoid valve provided on the exhaust port 16 and the fourth solenoid valve provided on the air outlet of the air duct 11 are opened, the induced draft fan 12 and the electric heating wire 14 are started, and the material is dried by hot air. When the value monitored by the humidity sensor reaches the set humidity value, the induced draft fan 12 and the electric heating wire 14 are turned off to complete the drying of the material. The dried material falls into the discharge chamber 22 by opening the first solenoid valve provided on the lower hopper 3, and then continues to be loaded and dried in the loading and drying chamber 21.

[0026] The material in the discharge chamber 22 is discharged to the feed port of the injection molding machine by opening the fifth solenoid valve provided on the discharge port 17, thereby enabling loading of the injection molding machine. Simultaneously, a second material level sensor monitors the material in the discharge chamber 22 in real time. When the material in the discharge chamber 22 reaches the minimum set value, the first solenoid valve provided on the lower hopper 3 opens. This opening of the first solenoid valve ensures that the material in the loading and drying chamber 21 has been completely dried. When the material in the discharge chamber 22 reaches the maximum set value, the first solenoid valve provided on the lower hopper 3 closes, thereby enabling continuous loading of the injection molding machine.

[0027] A return port 18 is provided on the sidewall of the discharge port 17, slanting downward. The end of the return port 18 is located above the barrel 10, and a sixth solenoid valve is installed on the return port 18. When the mechanism stops working, if there is any material remaining in the upper drying drum 2, the fifth solenoid valve on the discharge port 17 closes, and the first solenoid valve on the lower hopper 3 and the sixth solenoid valve on the return port 18 open, allowing the material to flow back into the barrel 10 through the return port 18.

[0028] A PLC controller 19 is provided on the outer wall of the loading drying cylinder 2, and the input end of the PLC controller 19 is respectively connected to the output ends of the first material level sensor, the second material level sensor and the humidity sensor; the output end of the PLC controller 19 is respectively connected to the controlled ends of the vacuum pump 1, the induced draft fan 12, the electric heating wire 14, the vibration motor 7, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve, the fifth solenoid valve and the sixth solenoid valve, thereby realizing automatic control of the mechanism.

[0029] When the utility model is in use, the discharge port 17 is connected to the feed port of the injection molding machine, the second solenoid valve provided on the air extraction port 15 is opened, the first solenoid valve provided on the lower hopper 3, the third solenoid valve provided on the exhaust port 16 and the fourth solenoid valve provided on the air outlet of the air duct 11 are closed, the vacuum pump 1 is started to extract air from the feeding and drying chamber 21, and the material is fed. When the value monitored by the first material level sensor reaches the set material value, the vacuum pump 1 is turned off, and the feeding is completed; then the second solenoid valve provided on the air extraction port 15 and the first solenoid valve provided on the lower hopper 3 are closed, and the vacuum pump 1 is opened. The third solenoid valve provided on the exhaust port 16 and the fourth solenoid valve provided on the air outlet of the air duct 11 start the induced draft fan 12 and the electric heating wire 14 to dry the material by hot air. When the value monitored by the humidity sensor reaches the set humidity value, the induced draft fan 12 and the electric heating wire 14 are turned off to complete the drying of the material. The dried material falls into the discharge chamber 22 by opening the first solenoid valve provided on the lower hopper 3, and then continues to be loaded and dried in the loading and drying chamber 21. At the same time, the fifth solenoid valve provided on the discharge port 17 is opened to realize continuous loading of the injection molding machine.

Claims

1. A vacuum feeding mechanism for an injection molding machine, comprising a vacuum pump (1), wherein the vacuum port of the vacuum pump (1) is connected to a feeding drying cylinder (2) having a funnel-shaped bottom through an exhaust pipe, and the feeding drying cylinder (2) is connected to a barrel (10) for accommodating injection molding particles through a suction pipe (8), characterized in that: A funnel-shaped lower hopper (3) is provided inside the feeding drying cylinder (2), and the lower hopper (3) divides the interior of the feeding drying cylinder (2) into a feeding drying chamber (21) and a discharging chamber (22) provided upper and lower. An air suction port (15) connected to an air suction pipe is provided on the top of the feeding drying chamber (21), and the discharging end of the suction pipe (8) penetrates into the feeding drying chamber (21) from the side wall of the feeding drying chamber (21). A valve is provided inside the feeding drying chamber (21) located above the discharging end of the suction pipe (8) for blocking the injection molding. The particles enter the baffle plate (6) of the air extraction port (15); the side wall of the lower hopper (3) is connected to an air duct (11) arranged on the outer wall of the upper material drying cylinder (2); the outer end of the air duct (11) is connected to an induced draft fan (12) for drawing air to the upper material drying chamber (21); the air outlet of the induced draft fan (12) is provided with a filter plate (13) for filtering the induced air; and a plurality of electric heating wires (14) are provided in the air duct (11) below the filter plate (13) along the flow direction of the induced air and used to heat the induced air.

2. The vacuum feeding mechanism for an injection molding machine according to claim 1, characterized in that: Two ring plates (4) with through holes are horizontally arranged inside the feeding and drying chamber (21), which are spaced apart from each other and located above the discharge end of the suction pipe (8); the material blocking mesh plate (6) is arranged between the two ring plates (4) and connected to the two ring plates (4) through a spring (5); and a vibration motor (7) is also arranged on the material blocking mesh plate (6) for removing injection molded particles on the material blocking mesh plate (6).

3. The vacuum feeding mechanism for an injection molding machine according to claim 2, characterized in that: A PLC controller (19) is provided on the outer side wall of the feeding drying cylinder (2), and the output end of the PLC controller (19) is respectively connected to the controlled ends of the vacuum pump (1), the induced draft fan (12), the electric heating wire (14) and the vibration motor (7).

4. The vacuum feeding mechanism for an injection molding machine according to claim 3, characterized in that: A second solenoid valve is provided on the air extraction port (15); a first material level sensor and a humidity sensor are provided inside the loading and drying chamber (21), and a first solenoid valve is provided on the lower hopper (3); an exhaust port (16) is provided on the top of the loading and drying chamber (21), a third solenoid valve is provided on the exhaust port (16), and a fourth solenoid valve is provided on the air outlet of the air duct (11); a second material level sensor is provided inside the discharge chamber (22), a discharge port (17) is provided at the bottom of the loading and drying cylinder (2), and the discharge port (17) is connected to the discharge chamber (22) and used for connecting to the feed port of the injection molding machine, and a fifth solenoid valve is provided on the discharge port (17); the input end of the PLC controller (19) is respectively connected to the output ends of the first material level sensor, the second material level sensor and the humidity sensor, and the output end of the PLC controller (19) is respectively connected to the controlled ends of the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve and the fifth solenoid valve.

5. The vacuum feeding mechanism for an injection molding machine according to claim 4, characterized in that: A return port (18) is provided on the side wall of the discharge port (17) and is located above the barrel (10) and is used to return the remaining material in the feeding drying cylinder (2) to the barrel (10). A sixth solenoid valve is provided on the return port (18), and a controlled end of the sixth solenoid valve is connected to the output end of the PLC controller (19).

6. The vacuum feeding mechanism for an injection molding machine according to claim 1, characterized in that: A wide-mouthed suction hopper (9) is provided at the feeding end of the suction pipe (8) located in the barrel (10).

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