A single screw hot melt extruder

Abstract

The present invention discloses a single screw hot melt extruder, comprising: a working frame, a hot melt forming mechanism, a transmission frame and an extrusion screw and a reduction motor fixedly mounted on one side of the transmission frame, the hot melt forming mechanism and the transmission frame are fixedly mounted on the top surface of the working frame, the hot melt forming mechanism comprises a temperature control chamber, a heat transfer tube, a hot melt modification sleeve and a plurality of external heating sleeves, the heat transfer tube is divided into two sections and fixedly mounted on both sides of the hot melt modification sleeve, one end of the extrusion screw is fixedly connected to the output end of the transmission frame and the other end is rotatably sleeved on the inner side of the heat transfer tube. In the present invention, by setting a new transmission frame and an extrusion screw structure, the raw material particles for PP film production and the modifier are mixed and stirred in the rotational motion of a plurality of stirring teeth on the surface of the mixer to be modified in a hot melt state, and hot melt, modified mixing and extrusion are integrated to simplify the operation process and improve production efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of PP film production, in particular to a single-screw hot-melt extruder. Background Art

[0002] PP film is a polypropylene film. This film has good insulation properties and is widely used in electrical insulation. It is also soft and can be made very thin. It is also used in blister trays. However, this material also has many subdivisions. Through modification or the addition of additives, it can be divided into flame retardant, packaging grade, etc. The PP film extruder brings the PP raw material into the heating zone through the rotation of the screw, and the raw material is heated and melted in the heating zone. Then, the molten raw material is pushed to the die by the screw, and the shape and size of the die are controlled to form the desired film shape. Finally, the extruded film is cooled, pulled and rolled to obtain the finished PP film. .

[0003] Existing PP film extruders are usually composed of an extruder mainframe, a die head, a cooling device, a traction device, and a winding device. Among them, the extruder mainframe is the core part, including a screw, a heating system, a drive system, etc., and lacks a mixing structure. In the preparation stage of polypropylene particles, additives need to be mixed in to modify the particles. This process is usually called "masterbatch modification" or "masterbatch modification". In the masterbatch modification work, the particles are mainly melted and modified in advance or additives are added and granulated before being put into a screw extruder for use. The production process is cumbersome. In view of this, research and improvement are carried out on the existing problems, and a single-screw hot-melt extruder is provided to solve the current problems. The purpose is to achieve the purpose of solving problems and improving practical value through this technology. Summary of the invention

[0004] The present invention aims to solve one of the technical problems existing in the prior art or related technology.

[0005] To this end, the technical solution adopted by the present invention is: a single-screw hot-melt extruder, comprising: a working frame, a hot-melt molding mechanism, a transmission frame and an extrusion screw and a reduction motor fixedly installed on one side of the transmission frame, the hot-melt molding mechanism and the transmission frame are fixedly installed on the top surface of the working frame, the hot-melt molding mechanism comprises a temperature control chamber, a heat-conducting cylinder, a hot-melt modified sleeve seat and a plurality of external heating sleeve seats, the heat-conducting cylinder is divided into two sections and is respectively fixedly installed on both sides of the hot-melt modified sleeve seat, one end of the extrusion screw is fixedly connected to the output end of the transmission frame and the other end is rotatably sleeved on the inner side of the heat-conducting cylinder, and a plurality of the hot-melt modified sleeve seats are fixedly sleeved on the outer side of the heat-conducting cylinder and fixedly installed inside the temperature control chamber;

[0006] The extrusion screw comprises a rotating shaft rod, a conveying rotary rod, a mixer and an extrusion rotary rod which are connected in sequence from left to right; one end of the rotating shaft rod is provided with a spline shaft head for connecting to a reduction motor; a current stabilizer is provided on the surface of the extrusion rotary rod; the rotating shaft rod, the conveying rotary rod, the mixer, the extrusion rotary rod and the current stabilizer are an integrally formed structure; a plurality of stirring teeth are provided on the surface of the mixer, and electrode contacts are provided at the ends of the stirring teeth; a mixing tube cavity whose two ends are fixedly connected to a heat conductor is provided on the inner side of the hot-melt modified sleeve; an electrode slip ring is provided on the inner side of the mixing tube cavity; the electrode contact slides in contact with the inner side of the electrode slip ring.

[0007] In a preferred example, the present invention can be further configured as follows: a water cooling coil is provided on the inner side of the temperature control chamber and is connected to a circulating water cooling component, and the external heating sleeve seat and the hot melt modified sleeve seat are both metal sleeve structures.

[0008] In a preferred example, the present invention can be further configured as follows: the inner sides of the external heating sleeve seat and the mixer are both provided with electric heating wires for heating the raw material pellets for PP film production, adjacent external heating sleeve seats are spaced apart, and the arrangement density of the external heating sleeve seats gradually increases toward the end of the hot melt modified sleeve seat.

[0009] In a preferred example, the present invention can be further configured as follows: the diameters of the conveying rotary rod and the extruding rotary rod gradually decrease from away from the mixer to close to the mixer, and the surfaces of the conveying rotary rod and the extruding rotary rod are both provided with spiral blades, and the outer periphery of the spiral blades slides in contact with the inner wall of the heat conducting tube.

[0010] In a preferred example, the present invention can be further configured as follows: the stirring teeth on the surface of the mixer are arranged in a spiral shape, and the spiral rotation direction is opposite to the spiral blade rotation direction.

[0011] In a preferred example, the present invention can be further configured as follows: the electrode contact is a metal ball structure, the electrode slip ring is a copper ring structure, and the electrode contact elastically abuts against the surface of the electrode slip ring.

[0012] In a preferred example, the present invention can be further configured as follows: a plurality of linear grooves for the molten liquid to pass through are provided on the surface of the flow stabilizer, and the outer periphery of the flow stabilizer is slidably fitted with the inner side of the heat conducting tube.

[0013] The beneficial effects achieved by the present invention are:

[0014] 1. In the present invention, a novel transmission frame and an extrusion screw structure are provided, and the raw material particles for PP film production and the modifier are mixed and stirred by utilizing the rotational movement of a plurality of stirring teeth on the surface of the mixer to perform modification in a hot melt state, and hot melt, modified mixing and extrusion are integrated to simplify the operation process and improve production efficiency.

[0015] 2. In the present invention, a tapered connection mode is used between the conveying rotary rod and the extrusion rotary rod and the end of the mixer to form a cavity area in the middle section of the heat-conducting cylinder, so that more particles can be rotated and stirred by the mixer in this area to improve the mixing effect with the modifier, and the stirring teeth are rotated to connect the circuit for independent heating, thereby increasing the modification working temperature and improving the molding effect.

[0016] 3. In the present invention, a segmented extrusion screw structure is provided, and each working zone is formed by combining a conveying screw, a mixer and an extrusion screw. A pre-melting conveying zone, a modified mixing zone and a pressure extrusion zone are formed according to function. In addition, a plurality of independent external heating sleeves are used to control the temperature zone to form a temperature gradient. Internal heating is used inside the hot-melt modification sleeve to evenly heat the modified zone and improve product performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the internal structure of a temperature control cabin according to an embodiment of the present invention;

[0019] Figure 3 It is a schematic diagram of the overall cross-sectional structure of an embodiment of the present invention;

[0020] Figure 4 This is a schematic diagram of the extrusion screw structure of an embodiment of the present invention;

[0021] Figure 5 It is a schematic diagram of a partially enlarged structure of an extrusion screw according to an embodiment of the present invention;

[0022] Figure 6 It is a schematic diagram of the cross-sectional structure of a hot-melt modified sleeve according to an embodiment of the present invention.

[0023] Reference numerals:

[0024] 100. Working frame;

[0025] 200, hot melt forming mechanism; 210, temperature control chamber; 220, heat transfer tube; 230, external heating sleeve seat; 240, hot melt modified sleeve seat; 221, outlet flange; 241, mixing tube cavity; 242, electrode slip ring;

[0026] 300, transmission frame; 310, reduction motor;

[0027] 400, extrusion screw; 410, rotating shaft; 420, conveying rotary rod; 430, mixer; 440, extrusion rotary rod; 450, flow stabilizer; 411, spline shaft head; 431, stirring teeth; 432, electrode contact. DETAILED DESCRIPTION

[0028] To make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in combination with specific implementations and with reference to the accompanying drawings. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0029] A single-screw hot-melt extruder provided by some embodiments of the present invention will be described below in conjunction with the accompanying drawings.

[0030] Combination Figure 1-6 As shown, a single-screw hot-melt extruder provided by the present invention comprises: a working frame 100, a hot-melt forming mechanism 200, a transmission frame 300, an extrusion screw 400, and a reduction motor 310 fixedly mounted on one side of the transmission frame 300, the hot-melt forming mechanism 200 and the transmission frame 300 are fixedly mounted on the top surface of the working frame 100, the hot-melt forming mechanism 200 comprises a temperature control chamber 210, a heat-conducting cylinder 220, a hot-melt modified sleeve seat 240 and a plurality of external heating sleeve seats 230, the heat-conducting cylinder 220 is divided into two sections and fixedly mounted on both sides of the hot-melt modified sleeve seat 240, one end of the extrusion screw 400 is fixedly connected to the output end of the transmission frame 300 and the other end is rotatably sleeved on the inner side of the heat-conducting cylinder 220, and a plurality of hot-melt modified sleeve seats 240 are fixedly sleeved on the outer side of the heat-conducting cylinder 220 and fixedly mounted on the inside of the temperature control chamber 210;

[0031] The extrusion screw 400 includes a rotating shaft rod 410, a conveying rotary rod 420, a mixer 430 and an extrusion rotary rod 440 which are connected in sequence from left to right. One end of the rotating shaft rod 410 is provided with a spline shaft head 411 for connecting to the reduction motor 310. The surface of the extrusion rotary rod 440 is provided with a flow stabilizer 450. The rotating shaft rod 410, the conveying rotary rod 420, the mixer 430, the extrusion rotary rod 440 and the flow stabilizer 450 are an integrally formed structure. The surface of the mixer 430 is provided with a plurality of stirring teeth 431, and the ends of the stirring teeth 431 are provided with electrode contacts 432. The inner side of the hot melt modified sleeve 240 is provided with a mixing tube cavity 241 whose two ends are fixedly connected to the heat conductor 220, and the inner side of the mixing tube cavity 241 is provided with an electrode slip ring 242, and the electrode contact 432 slides and abuts against the inner side of the electrode slip ring 242.

[0032] In this embodiment, a water cooling coil is provided on the inner side of the temperature control chamber 210 and is connected to a circulating water cooling component. The external heating sleeve seat 230 and the hot melt modified sleeve seat 240 are both metal sleeve structures.

[0033] Specifically, a water cooling assembly is provided inside the temperature control chamber 210 and rapid heat conduction cooling is performed through the thermal conductivity of metal, and temperature control is performed in cooperation with the external heating sleeve seat 230 and the internal electric heating structure of the hot melt modified sleeve seat 240 .

[0034] In this embodiment, electric heating wires are provided on the inner sides of the external heating sleeve seat 230 and the mixer 430 for heating the raw material pellets for PP film production. Adjacent external heating sleeve seats 230 are distributed at intervals, and the arrangement density of the external heating sleeve seats 230 gradually increases towards the end of the hot melt modified sleeve seat 240.

[0035] Specifically, the heating efficiency is improved by arranging the external heating sleeve 230 more densely at the two sections of the hot melt modification sleeve 240, and the external heating sleeve 230 is arranged more sparsely at the end away from the hot melt modification sleeve 240 and close to the outlet flange 221, so that the heating efficiency of the masterbatch is reduced to facilitate reaching a suitable molding temperature at the outlet flange 221.

[0036] In this embodiment, the diameters of the conveying rotary rod 420 and the extruding rotary rod 440 gradually decrease from away from the mixer 430 to close to the mixer 430 . The surfaces of the conveying rotary rod 420 and the extruding rotary rod 440 are both provided with spiral blades, and the outer periphery of the spiral blades slides in contact with the inner wall of the heat conducting cylinder 220 .

[0037] Furthermore, the stirring teeth 431 on the surface of the mixer 430 are arranged in a spiral shape, and the spiral rotation direction is opposite to the spiral blade rotation direction.

[0038] Specifically, the PP film production raw material particles and the modifier are mixed and stirred by rotating a plurality of stirring teeth 431 on the surface of the mixer 430 to perform modification in a hot melt state.

[0039] In this embodiment, the electrode contact 432 is a metal ball structure, the electrode slip ring 242 is a copper ring structure, and the electrode contact 432 elastically abuts against the surface of the electrode slip ring 242 .

[0040] Specifically, by utilizing the movement abutment between the electrode contact 432 and the electrode slip ring 242, current is input during the rotation of the mixer 430 to ensure that the heating wire inside the mixer 430 is energized, and the rotating mixer 430 is utilized to heat the inside of the material to make its heat distribution more uniform.

[0041] In this embodiment, a plurality of linear grooves for the molten liquid to pass through are provided on the surface of the flow stabilizer 450 , and the outer periphery of the flow stabilizer 450 is slidably fitted with the inner side of the heat conducting cylinder 220 .

[0042] Specifically, the slurry overflows on the surface of the flow stabilizer 450, and evenly distributes the slurry on the periphery of the extrusion rotary rod 440, thereby avoiding bubbles in the molded product caused by the conveying hollow cavity, and further improving the quality of the finished product.

[0043] The working principle and use process of the present invention:

[0044] During the masterbatch modification extrusion work, a plurality of hot melt modification sleeves 240 are arranged to form different temperatures, and different temperature working ranges are established inside the temperature control chamber 210. The electrode contact 432 and the electrode slip ring 242 are in sliding contact during the rotation of the mixer 430 to connect the electrodes, so that the built-in electric heating structure of the mixer 430 generates heat, and the heating balance of the masterbatch inside the mixing tube cavity 241 is further improved to ensure sufficient mixing and dispersion, and to prevent the problem of uneven mixing and dispersion of additives caused by incomplete hot melting of the polyethylene masterbatch due to low temperature; the masterbatch is added through one end of the heat-conducting cylinder 220, and the additive is mixed in, and the masterbatch is heated by the rotation of the conveying rotary rod 420. During the movement, the material is gradually heated and melted inside the heat-conducting cylinder 220 and pushed into the mixing tube cavity 241. After the mixer 430 rotates, the additives and the masterbatch melt are stirred by a plurality of stirring teeth 431 to fully mix the additives and the masterbatch melt. During the continuous conveying of the masterbatch, the mixed and modified melt is pushed out of the mixing tube cavity 241. The extrusion rotary rod 440 rotates to gradually form an extrusion force inside the heat-conducting cylinder 220, and the material is extruded through one end of the outlet flange 221. Different formers can be connected to the port of the outlet flange 221, so that the masterbatch forms a basic PP film at the port of the former. After the material is discharged, it undergoes subsequent cooling, stretching and other processes to ensure the formation of a continuous film with suitable size and performance.

[0045] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A single screw hot melt extruder, characterized in that: include: A working frame (100), a hot melt molding mechanism (200), a transmission frame (300), an extrusion screw (400), and a reduction motor (310) fixedly mounted on one side of the transmission frame (300); the hot melt molding mechanism (200) and the transmission frame (300) are fixedly mounted on the top surface of the working frame (100); the hot melt molding mechanism (200) comprises a temperature control chamber (210), a heat conduction cylinder (220), and a hot melt modified sleeve (240). and a plurality of external heating sleeve seats (230), the heat-conducting tube (220) being divided into two sections and respectively fixedly mounted on both sides of the hot-melt modified sleeve seat (240), one end of the extrusion screw (400) being fixedly connected to the output end of the transmission frame (300) and the other end being rotatably sleeved on the inner side of the heat-conducting tube (220), and a plurality of the hot-melt modified sleeve seats (240) being fixedly sleeved on the outer side of the heat-conducting tube (220) and fixedly mounted on the inside of the temperature-controlled chamber (210); The extrusion screw rod (400) comprises a rotating shaft rod (410), a conveying rotating rod (420), a mixer (430), and an extrusion rotating rod (440) which are connected in sequence from left to right. One end of the rotating shaft rod (410) is provided with a spline shaft head (411) for connecting to a reduction motor (310). A flow stabilizer (450) is provided on the surface of the extrusion rotating rod (440). The mixer (430) and the current stabilizer (450) are integrally formed structures, a plurality of stirring teeth (431) are provided on the surface of the mixer (430), and electrode contacts (432) are provided at the ends of the stirring teeth (431), a mixing tube cavity (241) whose two ends are fixedly connected to the heat conductor (220) is provided on the inner side of the hot melt modified sleeve (240), and an electrode slip ring (242) is provided on the inner side of the mixing tube cavity (241), and the electrode contact (432) is in sliding contact with the inner side of the electrode slip ring (242).

2. A single screw hot melt extruder according to claim 1, characterized in that: The inner side of the temperature control chamber (210) is provided with a water cooling coil and is connected to a circulating water cooling component. The external heating sleeve seat (230) and the hot melt modified sleeve seat (240) are both metal sleeve structures.

3. A single screw hot melt extruder according to claim 1, characterized in that: The inner sides of the external heating sleeve seat (230) and the mixer (430) are both provided with electric heating wires for heating the raw material pellets for PP film production. Adjacent external heating sleeve seats (230) are arranged at intervals, and the arrangement density of the external heating sleeve seats (230) gradually increases towards the end of the hot melt modified sleeve seat (240).

4. A single screw hot melt extruder according to claim 1, characterized in that: The diameters of the conveying rotary rod (420) and the extruding rotary rod (440) gradually decrease in a direction away from the mixer (430) and towards the mixer (430), and spiral blades are provided on the surfaces of the conveying rotary rod (420) and the extruding rotary rod (440), and the outer peripheries of the spiral blades are slidably fitted with the inner wall of the heat conducting cylinder (220).

5. A single screw hot melt extruder according to claim 4, characterized in that: The stirring teeth (431) on the surface of the mixer (430) are arranged in a spiral shape, and the spiral rotation direction is opposite to the spiral blade rotation direction.

6. A single screw hot melt extruder according to claim 1, characterized in that: The electrode contact (432) is a metal ball structure, the electrode slip ring (242) is a copper ring structure, and the electrode contact (432) elastically abuts against the surface of the electrode slip ring (242).

7. A single screw hot melt extruder according to claim 1, characterized in that: The surface of the flow stabilizer (450) is provided with a plurality of linear grooves for the passage of molten liquid, and the outer periphery of the flow stabilizer (450) is slidably fitted with the inner side of the heat conducting cylinder (220).

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