Improved double-screw pressing exhaust device

Abstract

The utility model provides an improved double-screw pressing and exhausting device, which is characterized in that a pressing screw is improved into a mutually meshed double-screw structure, so that an exhausting channel at the pressing screw is widened, the exhausting efficiency is improved, the risk of melt overflow is reduced, the double screws rotate relatively, materials are forcibly conveyed back to an extruder barrel, and the melt overflow risk is reduced. The self-cleaning work of the material pressing screw rod is realized; the exhaust device is fixedly connected with the lifting mechanism, the exhaust device descends to the extruder barrel in a use state, and the exhaust device can be separated from the extruder barrel in a cleaning state, so that low polymers adhered to the lower parts of the double screws can be conveniently and simply cleaned; the lifting mechanism comprises a worm gear and a worm, and the worm is rotated by adjusting the worm gear, so that the quick lifting function is realized; the material pressing screw barrel is of a split structure, the material pressing screw barrel can be completely split through a rotating shaft or a hinge, and the interior of the material pressing screw barrel can be conveniently and thoroughly cleaned.

Description

Technical Field

[0001] This utility model relates to the technical field of melt material processing equipment, specifically to an improved twin-screw pressing and venting device. Background Technology

[0002] When plastic melt is melted and extruded through equipment such as extruders, air, moisture, and other components are often mixed in the melt. If these components are not removed, they will cause a decline in the quality of the material after mixing. To solve the above problems, extruders usually have vents or vacuum pumps connected to the feed port or barrel. However, the above-mentioned methods still have many shortcomings. For example, the vents or vacuum pumps are easy to get clogged and require frequent maintenance; after the material cools, blockage sites are formed, which are inconvenient to clean; and high-pressure melt is easy to overflow from the vents.

[0003] Utility model patent CN208576069U discloses a pressing and venting device. This device uses a pressure screw driven by a geared motor added to a first venting pipe to press down the overflowing molten material under pressure, while air and other components are extracted through a second venting pipe. However, the pressure screw itself can become stuck to the overflowing material, and if not cleaned after the molten material cools and solidifies, it cannot function properly. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an improved twin-screw extrusion device that can extract air, moisture and other substances from the extruder, reduce overflow problems, and provide a self-cleaning function for the extrusion device.

[0005] To achieve the above objectives, the technical solution provided by this utility model includes:

[0006] An improved twin-screw press venting device includes a press screw barrel and an vent pipe connected to and communicating with the press screw barrel sidewall. The press screw barrel contains two meshing screws. One end of each screw is equipped with a gear distribution box, and the input end of the gear distribution box is connected to a geared motor. The twin screws are connected to the geared motor through the gear distribution box and are driven to rotate by the geared motor. One end of the press screw barrel is equipped with a barrel connection cover for molten material.

[0007] Furthermore, the exhaust pipe is connected to a vacuum pump, and a vacuum gauge is installed on the exhaust pipe.

[0008] Furthermore, the pressure screw cylinder is vertically arranged, and the exhaust pipe is horizontally or inclined upwards.

[0009] Furthermore, the geared motor is a variable frequency geared motor.

[0010] To elevate the exhaust device so that the twin screws can be inserted into the extruder barrel, with the lower end of the twin screws flush with the inner wall of the extruder barrel, thereby reducing material overflow at the connection between the barrel and the exhaust device, the technical solution provided by this utility model includes: the exhaust device is also fixedly connected to a lifting mechanism.

[0011] Furthermore, the lifting mechanism includes a mounting base, a screw jack is installed inside the mounting base, the screw jack is provided with a screw, the screw is rotatably connected to a threaded sleeve, an exhaust device is connected to the top surface of the threaded sleeve, and a worm gear is fixedly installed at the lower part of the screw inside the screw jack.

[0012] Furthermore, the worm gear is connected to a worm, which is connected to the main shaft of the lifting motor, or a hand crank extends from the worm gear.

[0013] Furthermore, a steering rod is also connected between the threaded sleeve and the exhaust device.

[0014] To make the exhaust device easier to clean, the technical solution provided by this utility model also includes that the pressure screw cylinder is a split structure, and the split structure pressure screw cylinder includes a detachable first half cylinder and a second half cylinder.

[0015] Furthermore, the first and second half-cylinders are rotatably connected by a hinge or a pivot.

[0016] Furthermore, the first half-cylinder and / or the second half-cylinder are provided with a rotating handle.

[0017] The advantages and beneficial effects of this utility model are as follows:

[0018] 1. The pressure screw barrel is equipped with two meshing screws. The two screws are connected to the variable frequency reduction motor through the gear distribution box. Compared with the single screw, the exhaust efficiency is improved. When the two screws rotate, the two screws can clean each other and force the melt that is stuck to each other into the barrel, preventing the melt from sticking to the two screws and causing blockage.

[0019] 2. The exhaust device is fixedly connected to a lifting mechanism. The movement of the lifting mechanism separates the exhaust device from the extruder barrel, making the exhaust device easy to inspect, maintain and clean. Specifically, after the exhaust device is raised, it is convenient to clean the oligomer residues on the surface of the twin screw.

[0020] 3. The driving device in the lifting mechanism is a worm gear, which transmits power to the lead screw through a worm wheel, enabling more efficient power transmission and thus achieving rapid lifting.

[0021] 4. The pressure screw barrel is designed as a split structure, connected by a hinge / shaft. After the pressure screw barrel is disassembled, it is convenient to thoroughly clean the oligomers adhering to the surface of the twin screws. Attached Figure Description

[0022] Figure 1 This is a structural schematic diagram of the present invention in use;

[0023] Figure 2 This is a schematic diagram of the structure of this utility model in the cleaned state;

[0024] Figure 3 This is a schematic diagram of the structure of the pressure screw barrel of this utility model;

[0025] Figure 4 This is a schematic diagram of the internal structure of the screw jack of this utility model;

[0026] In the picture:

[0027] 1-Pressure screw barrel, 2-Exhaust pipe, 3-Twin screw, 4-Gear distribution box, 5-Reduction motor, 6-Barrel connecting cover, 7-Vacuum pump interface, 8-Vacuum gauge, 9-Mounting base, 10-Screw jack, 11-Screw, 12-Screw sleeve, 13-Worm gear, 14-Hand crank, 15-Steering rod, 16-First half-barrel, 17-Second half-barrel, 18-Shaft, 19-Rotating handle, 20-Extruder barrel, 21-Worm gear. Detailed Implementation

[0028] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model. Example

[0029] Please see Figures 1-2 An improved twin-screw extrusion device includes a screw barrel 1 and an exhaust pipe 2 connected to and communicating with the side wall of the screw barrel 1. A pair of meshing twin screws 3 are installed inside the screw barrel 1. A gear distribution box 4 is installed at one end of each twin screw 3, and a geared motor 5 is connected to the input end of the gear distribution box 4. The twin screws 3 are connected to and driven by the geared motor 5 through the gear distribution box 4. A barrel connection cover 6 for the extruder barrel 20 containing the molten material is provided at one end of the screw barrel 1. The exhaust pipe 2 is connected to a vacuum pump through a vacuum pump interface 7 and is also equipped with a vacuum gauge 8. The screw barrel 1 is vertically positioned, and the exhaust pipe 2 is horizontally or inclined upwards. The geared motor 5 is preferably a variable frequency geared motor. The length of the twin screws 3 should be as close as possible to the sum of the length of the screw barrel 1 and the wall thickness of the extruder barrel 20. The geared motor 5 is preferably a variable frequency geared motor.

[0030] Please see Figures 1-4To elevate the exhaust device so that the twin screws can be inserted into the extruder barrel 20, with the lower ends of the twin screws flush with the inner wall of the barrel, reducing overflow at the connection between the barrel and the exhaust device, the exhaust device is also fixedly connected to a lifting mechanism. The lifting mechanism includes a mounting base 9, within which a screw jack 10 is installed. The screw jack 10 has a lead screw 11 mounted on it, and a threaded sleeve 12 is rotatably connected to the lead screw 11. The exhaust device is mounted on the threaded sleeve 12. Inside the screw jack 10, a worm gear 13 is fixedly installed on the lead screw 11. A worm 21 meshing with the worm gear 13 is connected to the main shaft of the lifting motor, or a hand crank 14 extends directly outward from the worm 21 body. The threaded sleeve 12 and the exhaust device can also be connected via a steering rod 15. This worm gear structure, consisting of the worm gear and lead screw, enables efficient transmission and faster lifting movement of the lifting mechanism. The hand crank extending from the worm or its direct connection to the lifting motor facilitates lifting operations.

[0031] It should be noted that the threaded sleeve 12 can be provided with a guide rod along the axis of the lead screw 11 so that the threaded sleeve 12 body does not rotate when the lead screw rotates, but only rises and falls with the rotation; or it can be guided by the connection relationship between the twin screws 3 in the exhaust device connected to the steering rod 15 and the barrel.

[0032] Please see Figure 3 To facilitate cleaning of the exhaust device, the technical solution provided by this utility model further includes a split structure for the pressure screw cylinder 1, comprising a detachable first half-cylinder 16 and a second half-cylinder 17. The first half-cylinder 16 and the second half-cylinder 17 are rotatably connected by a hinge or a rotating shaft 18. The first half-cylinder 16 and / or the second half-cylinder 17 are provided with a rotating handle 19 for auxiliary rotation. The split structure of the pressure screw cylinder can be locked by buckles or bolts. One half-cylinder can be fixedly installed with the gear distribution box, the geared motor housing, etc. The other half-cylinder rotates relative to it via a hinge / rotating shaft, avoiding too many moving parts that would make operation inconvenient and reducing the possibility of leakage between the pressure screw cylinder and the gear distribution box.

[0033] After installing the improved twin-screw extrusion device provided by this utility model with the vacuum pump, extruder, etc., the twin screws are inserted into the inner wall of the extruder barrel by hand-cranking or using a lifting motor to engage the lifting mechanism with the barrel connecting cover. During operation, melt moves along the axis of the extruder barrel. The geared motor and vacuum pump are then turned on. The geared motor drives the two twin screws to rotate through the gear distribution box. The vacuum pump provides a negative pressure to draw in air, water vapor, and oligomers from the extruder barrel. The negative pressure achieved by the vacuum pump is monitored in real time using a vacuum gauge to adjust the pump pressure. Due to the high temperature and pressure within the extruder barrel, the melt overflows from the barrel connecting cover. This overflowed material is then forcibly returned to the barrel by the twin screws. During this process, the vacuum pump's negative pressure draws out air, water vapor, and oligomers from the barrel, improving the flow state of the melt within the barrel. When the twin-screw is working, a small amount of melt will adhere to the surface of the twin screw. Through the meshing and rotation of the twin screws, the adhered melt can also be sent back into the barrel.

[0034] After the extruder finishes its work, turn off the vacuum pump and geared motor. Move the lifting mechanism to pull the twin screws out of the barrel connection cover. At this point, the bottom of the twin screws will be exposed, allowing for direct cleaning. If the extruder has been running for too long and the twin screws are completely stuck to the melt, the split-structure pressure screw barrel can be opened to fully expose the twin screws for thorough cleaning.

[0035] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. An improved twin-screw press venting device, comprising a press screw barrel and an venting pipe connected to and communicating with the press screw barrel sidewall, characterized in that: The pressing screw barrel is equipped with a pair of meshing screws. One end of the pair of screws is equipped with a gear distribution box. The input end of the gear distribution box is connected to a reduction motor. The pair of screws are connected to the reduction motor through the gear distribution box and are driven to rotate by the reduction motor. One end of the pressing screw barrel is equipped with a barrel connection cover.

2. The improved twin-screw press venting device according to claim 1, characterized in that: The exhaust pipe is connected to a vacuum pump, and a vacuum gauge is installed on the exhaust pipe.

3. The improved twin-screw press venting device according to claim 1 or 2, characterized in that: The pressure screw cylinder is set vertically, and the exhaust pipe is set horizontally or inclined upwards.

4. The improved twin-screw press venting device according to claim 1 or 2, characterized in that: The geared motor is a variable frequency geared motor.

5. The improved twin-screw press venting device according to claim 1 or 2, characterized in that: The exhaust device is also fixedly connected to a lifting mechanism.

6. The improved twin-screw press venting device according to claim 5, characterized in that: The lifting mechanism is a screw jack, which includes a screw, a threaded sleeve connected to the screw, an exhaust device fixedly installed to the threaded sleeve, and a worm gear fixedly installed at the lower part of the screw inside the screw jack.

7. The improved twin-screw press venting device according to claim 6, characterized in that: The worm gear is equipped with a worm, which is connected to the main shaft of the lifting motor or extends outward to form a hand crank.

8. The improved twin-screw press venting device according to claim 6 or 7, characterized in that: A steering rod is also connected between the threaded sleeve and the exhaust device.

9. The improved twin-screw press venting device according to claim 1, characterized in that: The pressure screw barrel has a split structure, which includes a detachable first half-cylinder and a second half-cylinder.

10. The improved twin-screw press venting device according to claim 9, characterized in that: The first half-cylinder and the second half-cylinder are rotatably connected by a hinge or a pivot, and the first half-cylinder and / or the second half-cylinder are provided with a rotating handle.

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