阅读说明：本技术 用于塑料挤出机的高填充螺杆 (High-filling screw for plastic extruder ) 是由 何海潮 卢海芳 于 2019-10-08 设计创作，主要内容包括：本发明公开一种用于塑料挤出机的高填充螺杆,包括杆体和螺棱,杆体具有沿从尾部至头部方向依次连接的喂料段、压缩段、剪切段以及出料段,螺棱沿周向布置在杆体上且从喂料段螺旋延伸至部分出料段,螺棱的间距与杆体之间形成螺槽,压缩段具有逐渐变大的外径,在剪切段上,螺槽内设置有多个沿径向方向向外突出的波状部,多个波状部沿螺槽的走向布置,各个波状部均具有在径向方向上远离杆体的波峰以及在径向方向上靠近杆体的波谷,波状部的波谷处的螺槽深度大于波状部的波峰处的螺槽深度。经过多个波峰处的螺槽和多个波谷处的螺槽的交替循环后,能够使得物料在剪切段上达到更好的塑化和混合效果。(The invention discloses a high-filling screw for a plastic extruder, which comprises a rod body and a screw rib, wherein the rod body is provided with a feeding section, a compression section, a shearing section and a discharging section which are sequentially connected from the tail part to the head part, the screw rib is circumferentially arranged on the rod body and spirally extends from the feeding section to part of the discharging section, a screw groove is formed between the distance of the screw rib and the rod body, the compression section has an outer diameter which is gradually increased, a plurality of wavy parts which outwards protrude along the radial direction are arranged in the screw groove on the shearing section, the wavy parts are arranged along the trend of the screw groove, each wavy part is provided with a wave crest which is far away from the rod body in the radial direction and a wave trough which is close to the rod body in the radial direction, and the depth of the screw groove at the wave trough of the wavy parts is greater than that of the screw groove. After the alternate circulation of the spiral grooves at the plurality of wave crests and the spiral grooves at the plurality of wave troughs, the material can achieve better plasticizing and mixing effects on the shearing section.)

1. The utility model provides a high filling screw rod for plastic extruder, includes body of rod (1) and spiral shell arris (2), body of rod (1) have along feeding section (11), compression section (12), shearing section (13) and the ejection of compact section that connects gradually from afterbody to head direction, spiral shell arris (2) arrange along circumference body of rod (1) on and follow feeding section (11) spiral extend to the part ejection of compact section, the interval of spiral shell arris (2) with body of rod (1) between form spiral groove (3), compression section (12) have the external diameter of grow gradually, its characterized in that: on the shearing section (13), a plurality of wavy parts (4) protruding outwards along the radial direction are arranged in the screw groove (3), the wavy parts (4) are arranged along the trend of the screw groove (3), each wavy part (4) is provided with a wave crest (41) far away from the rod body (1) in the radial direction and a wave trough (42) close to the rod body (1) in the radial direction, and the depth of the screw groove at the wave trough (42) of the wavy part (4) is greater than that of the screw groove at the wave crest (41) of the wavy part (4).

2. the high-fill screw for a plastic extruder of claim 1, wherein: the ejection of compact section include along following barrier section (14), measurement section (15) and mixing section (16) that the afterbody of the body of rod (1) connects gradually to the head direction, barrier section (14) on be provided with along main arris (21) and vice arris (22) of circumference spiral extension, main arris (21) with vice arris (22) crisscross the arrangement mutually, main arris (21) with vice arris (22) between be provided with feed chute (31) and blown down tank (32) of arranging side by side, main arris (21) with vice arris (22) have the difference in height in radial direction, spiral arris (2) extend to measurement section (15), mixing section (16) on be provided with multirow pin (23) of arranging along its length direction, each row pin (23) all arrange along circumference.

3. the high-fill screw for a plastic extruder of claim 2, wherein: the ratio of the height difference to the diameter of the high filling screw is 0.008-0.012: 1.

4. The high-fill screw for a plastic extruder of claim 2, wherein: the ratio of the lengths of the feeding section (11), the compression section (12), the shearing section (13), the barrier section (14), the metering section (15) and the mixing section (16) is 7-8:3-4:10-12:2-3:3-4: 2-3.

5. the high-fill screw for a plastic extruder of claim 2, wherein: the ratio of the diameter of the metering section (15) to the diameter of the high fill screw is 0.85-0.92: 1.

6. The high-fill screw for a plastic extruder of claim 2, wherein: the ratio of the diameter of the mixing section (16) to the diameter of the high-filling screw is 0.75-0.85: 1.

7. the high-fill screw for a plastic extruder of claim 1, wherein: the maximum height of the wave crest (41) of the wave-shaped part (4) in the radial direction is smaller than the height of the screw rib (2) in the radial direction.

8. the high-fill screw for a plastic extruder of claim 1, wherein: two adjacent undulations (4) are arranged away from each other in the radial direction.

9. The high-fill screw for a plastic extruder of claim 1, wherein: the ratio of the depth of the thread groove at the crest (41) of the wavy portion (4) to the diameter of the high-fill screw is 0.02-0.05: 1.

10. The high-fill screw for a plastic extruder of claim 1, wherein: the ratio of the groove depth at the trough (42) of the wave (4) to the diameter of the high fill screw is 0.05-0.1: 1.

11. the high-fill screw for a plastic extruder of claim 1, wherein: the ratio of the diameter of the feeding section (11) to the diameter of the high-fill screw is 0.6-0.8: 1.

12. The high-fill screw for a plastic extruder of claim 1, wherein: the ratio of the diameter of the shearing section (13) to the diameter of the high-fill screw is 0.85-0.92: 1.

13. The high-fill screw for a plastic extruder of claim 1, wherein: the diameter of the high filling screw is 65-120 mm.

Technical Field

the invention relates to the technical field of plastic extrusion, in particular to an extrusion screw for a plastic extruder, which is mainly used for the extrusion production of high-filling products such as SPC (SPC) floors, WPC (wood Plastic composite) floors, PP corrugated pipes and the like.

Background

SPC is an abbreviation of Stone Plastic Composites, the main raw material is polyvinyl chloride resin, an extruder is combined with a T-shaped die to extrude an SPC base material, a three-roll or four-roll calender is used to respectively heat, laminate and emboss a PVC wear-resistant layer, a PVC color film and the SPC base material at one time, and glue is not used in the production process. WPC is a new composite material, and is characterized by being green and environment-friendly and replacing wood with plastic. Wood Plastic Composites (WPC) are an emerging class of materials, and in the most general sense the acronym WPC stands for a broad class of composites made from virgin or recycled plastics, such as High Density Polyethylene (HDPE), polypropylene (PP), Polystyrene (PS) and polyvinyl chloride (PVC), with natural fiber fillers, including Wood flour and scrim fibers. Polypropylene, PP for short, is a colorless, odorless, nontoxic and semitransparent solid substance. Polypropylene (PP) is a thermoplastic synthetic resin with excellent performance, and is colorless translucent thermoplastic light general-purpose plastic. The polypropylene has chemical resistance, heat resistance, electrical insulation, high-strength mechanical property, good high-wear-resistance processing property and the like, so that the polypropylene can be rapidly and widely developed and applied in a plurality of fields such as machinery, automobiles, electronic and electric appliances, buildings, textiles, packaging, agriculture, forestry, fishery, food industry and the like since the coming out.

Traditional screw rod of extruding includes the body of rod and spiral shell arris usually, and the body of rod has the feeding section that connects gradually along afterbody to head direction, the compression section, shear segment and ejection of compact section, and the spiral shell arris is arranged on the body of rod and is extended to the head from the afterbody spiral of the body of rod along circumference, forms the thread groove between the interval of spiral shell arris and the body of rod, and the compression section has the external diameter along its length direction grow gradually usually to make the thread groove degree of depth between screw rod and the barrel reduce gradually, thereby extrude the material. In general, materials are fed through a feeding section and conveyed along the direction from the tail part to the head part of a rod body, extruded through a compression section, plasticized and melted under the action of shearing heat of a shearing section, and finally extruded through a discharging section to form a product. In order to reduce the production cost of plastic products and improve certain properties of the plastic products, such as rigidity improvement, shrinkage reduction, coloring effect improvement and the like, a certain proportion of fillers are added into raw materials for plastic molding. Ordinary screw rod structure is to extruding of this kind of high filling material, and the plastify effect is poor, and the feed is unstable, and shearing temperature is high, and the material produces the decomposition easily, and the extrusion pressure that the material received is great, and the material is undulant great be unfavorable for the plastify and the mixture of material, lead to the goods defective rate to remain high.

Disclosure of Invention

In order to solve the above technical problems, an object of the present invention is to provide a high-filling screw for a plastic extruder having better plasticizing and mixing effects.

In order to achieve the purpose of the invention, the invention adopts the following technical scheme:

A high-filling screw for a plastic extruder comprises a screw body and a screw ridge, wherein the screw body is provided with a feeding section, a compression section, a shearing section and a discharging section which are sequentially connected along the direction from the tail part to the head part, the screw rib is arranged on the rod body along the circumferential direction and extends spirally from the feeding section to part of the discharging section, a thread groove is formed between the distance between the thread edges and the rod body, the compression section has an outer diameter which is gradually enlarged, on the shearing section, a plurality of wave parts protruding outwards along the radial direction are arranged in the screw groove, the wave parts are arranged along the trend of the screw groove, each wave part is provided with a wave crest far away from the rod body in the radial direction and a wave trough close to the rod body in the radial direction, the depth of the thread groove at the wave trough of the wave part is larger than that at the wave crest of the wave part.

Among the above-mentioned technical scheme, preferred, the ejection of compact section include along the follow barrier section, measurement section and the mixing section that the afterbody of the body of rod to head direction connected gradually, the barrier section on be provided with along main arris and the vice arris of circumference spiral extension, main arris with vice arris looks staggered arrangement, main arris with vice arris between be provided with feed chute and the blown down tank of arranging side by side, main arris with vice arris have the difference in height on the radial direction, the spiral arris extend to the measurement section, mixing section on be provided with along the multirow pin of its length direction range, each row the pin all arrange along circumference.

In the above technical solution, preferably, the ratio of the height difference to the diameter of the high-fill screw is 0.008-0.012: 1.

In the above technical solution, preferably, the ratio of the lengths of the feeding section, the compressing section, the shearing section, the barrier section, the metering section and the mixing section is 7-8:3-4:10-12:2-3:3-4: 2-3.

in the above technical solution, preferably, a ratio of the diameter of the metering section to the diameter of the high-fill screw is 0.85-0.92: 1.

In the above technical means, preferably, the ratio of the diameter of the kneading section to the diameter of the high-filling screw is 0.75 to 0.85: 1.

In the above aspect, preferably, a maximum height of a peak of the wavy portion in the radial direction is smaller than a height of the ridge in the radial direction.

In the above-described aspect, it is preferable that two adjacent beads are provided so as to be apart from each other in the radial direction.

In the above technical solution, preferably, a ratio of a depth of the screw groove at the peak of the wave-shaped portion to a diameter of the high-fill screw is 0.02 to 0.05: 1.

In the above aspect, preferably, a ratio of a depth of the thread groove at the trough of the wave-shaped portion to a diameter of the high-fill screw is 0.05 to 0.1: 1.

In the above technical solution, preferably, the ratio of the diameter of the feeding section to the diameter of the high-filling screw is 0.6-0.8: 1.

In the above technical solution, preferably, a ratio of the diameter of the shearing section to the diameter of the high-fill screw is 0.85-0.92: 1.

In the above technical solution, preferably, the diameter of the high filling screw is 65 to 120 mm.

According to the invention, the plurality of wave parts protruding outwards along the radial direction are arranged in the screw grooves on the shearing section, the plurality of wave parts are arranged along the trend of the screw grooves, each wave part is provided with a wave crest far away from the rod body in the radial direction and a wave trough close to the rod body in the radial direction, and the depth of the screw groove at the wave trough is greater than that of the screw groove at the wave crest, so that the shearing action of the material in the screw groove at the wave crest is greater than that of the screw groove at the wave trough, the shearing action of the material in the screw groove at the wave trough is weakened, the extrusion pressure of the material is released, the temperature is relieved, the material is not decomposed by excessive shearing heat, and the material can achieve better plasticizing and mixing effects on the shearing section after the alternate circulation of the screw grooves at the wave crests and the screw grooves at the wave troughs.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic structural view of a shear segment of the present invention;

FIG. 3 is an enlarged partial schematic view at A in FIG. 2;

FIG. 4 is a schematic cross-sectional view taken along line B-B of FIG. 2;

FIG. 5 is a schematic cross-sectional view taken along line C-C of FIG. 2;

FIG. 6 is a schematic view of the structure of the barrier segment of the present invention;

FIG. 7 is a schematic cross-sectional view of a barrier segment of the present invention;

FIG. 8 is a schematic diagram of the structure of the mixing section of the present invention;

FIG. 9 is a schematic cross-sectional view of a mixing section of the present invention;

wherein: 1. a rod body; 11. a feeding section; 12. a compression section; 13. cutting into sections; 14. a barrier section; 15. a metering section; 16. a mixing section; 111. a head portion; 112. a tail portion;

2. A screw edge; 21. a main edge; 22. a minor edge; 23. a pin;

3. A screw groove; 31. a feed chute; 32. a discharge chute;

4. A corrugated portion; 41. wave crest; 42. a wave trough.

Detailed Description

For the purpose of illustrating the technical content, the constructional features, the achieved objects and the effects of the invention in detail, reference will be made to the following detailed description of the embodiments in conjunction with the accompanying drawings.

the invention is mainly used for a plastic extruder to extrude high-filling materials.

as shown in fig. 1, the high-filling screw comprises a rod body 1 and a screw flight 2, wherein the rod body 1 comprises a feeding section 11, a compression section 12, a shearing section 13, a barrier section 14, a metering section 15 and a mixing section 16 which are connected in sequence from a tail part 112 to a head part 111. The barrier section 14, the metering section 15 and the mixing section 16 are used as discharging sections, when the materials reach the three sections, the materials are basically in a molten state to be discharged, and a small part of the incompletely molten materials are further plasticized and mixed on the three sections, and finally reach the molten state. The screw rib 2 is arranged on the rod body 1 along the circumferential direction and extends spirally from the feeding section 11 to a part of the discharging section. Specifically, the feeding section 11, the compression section 12, the shearing section 13 and the metering section 15 are all provided with screw ridges 2, and screw grooves 3 are formed between the intervals of the screw ridges 2 and the rod body 1. When the high-filling screw is assembled on a plastic extruder for use, the high-filling screw is matched with an inner hole of a cylinder of the plastic extruder, a material advances along the trend of the screw groove 3 from the tail part 112 direction to the head part 111 direction, is extruded on the compression section 12, is subjected to shearing action on the shearing section 13, is plasticized, mixed and melted, and finally reaches the discharge section, and is further completely plasticized to be melted for extruding a product. In this example, the diameter D of the high-filling screw is 65 to 120 mm, and is suitable for the extrusion operation of high-filling materials in extruders of various specifications.

In order to increase the conveying capacity of high-filling materials and improve the feeding efficiency, the structure of the feeding section 11 is a deep groove bottom diameter, namely the diameter of the rod body 1 on the section is smaller, the depth of the spiral groove 3 is larger, and the diameter D1 of the feeding section 11 is 0.6-0.8D.

The compression section 12 has a gradually increasing outer diameter d2, in which the depth of the screw groove 3 gradually decreases from the tail 112 to the head 111 of the rod body 1, and the material is compressed on the section and gradually compacted.

As shown in fig. 2 and 3, in the shearing segment 13, a plurality of wavy parts 4 protruding outward in the radial direction are provided in the screw groove 3, the plurality of wavy parts 4 are arranged along the running direction of the screw groove 3, and two adjacent wavy parts 4 are arranged away from each other in the radial direction. Each wave part 4 is provided with a wave crest 41 far away from the rod body 1 in the radial direction and a wave trough 42 close to the rod body 1 in the radial direction, the maximum height of the wave crest 41 of the wave part 4 in the radial direction is smaller than the height of the screw ridge 2 in the radial direction, so that a space is formed between the wave crest 41 of the wave part 4 and the screw ridge 2, materials can pass through the space between the wave crest 41 and the screw ridge 2, and the shearing action of the screw grooves of the materials at the wave crest 41 is intensified. As shown in fig. 4 and 5, a distance between the crest 41 and the flight 2 of the wave-shaped portion 4 (i.e., the flight depth H1 at the crest 41) is smaller than a distance between the trough 42 and the flight 2 of the wave-shaped portion 4 (i.e., the flight depth H2 at the trough 42), so that the flight depth at the trough 42 of the wave-shaped portion 4 is greater than the flight depth at the crest 41 of the wave-shaped portion 4, the shearing action of the flight at the trough 42 of the material is relatively weakened, the extrusion pressure applied to the material is released, the temperature is relaxed, the material is not decomposed by excessive shearing heat, and after the alternating circulation of the flight at the crests 41 and the flight at the troughs 42, the material can achieve better plasticizing and mixing effects at the shearing section 13. Wherein the diameter D3 of the shear segment 13 is 0.85-0.92D, the groove depth H1 at the crest 41 of the wave 4 is 0.02-0.05D, and the groove depth H2 at the trough 42 of the wave 4 is 0.05-0.1D.

As shown in fig. 6 and 7, the barrier segment 14 is provided with a main rib 21 and a secondary rib 22 which extend spirally along the circumferential direction, the rotation directions of the main ribs 21 and the auxiliary ribs 22 are consistent with the rotation direction of the screw rib 2, the main ribs 21 and the auxiliary ribs 22 are arranged in a staggered mode, a feeding groove 31 and a discharging groove 32 are arranged between the main ribs 21 and the auxiliary ribs 22 in parallel, the main ribs 21 and the auxiliary ribs 22 are spaced in the radial direction, materials can enter from the feeding groove 31 when passing through the barrier section 14, and flows into the discharge chute 32 across the space between the main rib 21 and the auxiliary rib 22, the incompletely melted material is driven by the rotation of the high filling screw to form a vortex between the feed chute 31 and the discharge chute 32, the flow direction of the vortex is opposite to the advancing direction of the material, this enables a small part of the incompletely melted material to be subjected to a higher shearing action on the segment and further plasticised, while the completely melted material travels along the discharge chute 32 onto the metering segment 15. Wherein the diameter D4 of the barrier section 14 is identical to the diameter D of the high fill screw, and the difference δ in height between the major and minor ribs 21, 22 in the radial direction is 0.008-0.012D.

The screw rib 2 extends to the metering section 15, and the ratio of the length L1 of the feeding section 11, the length L2 of the compression section 12, the length L3 of the shearing section 13, the length L4 of the barrier section 14, the length L5 of the metering section 15 and the length L6 of the mixing section 16 is 7-8:3-4:10-12:2-3:3-4:2-3, so that the metering section 15 is designed to be longer, stable pressure is gradually built after materials are conveyed by the metering section 15, and stirring of extrusion is reduced. As shown in fig. 8 and 9, the kneading segment 16 is provided with a plurality of rows of pins 23 arranged in the longitudinal direction thereof, and the pins 23 in each row are arranged in the circumferential direction. The materials are dispersed and mixed by the pins 23, and the melted materials are divided into a plurality of strands and then are converged again, so that the good dispersing and mixing effect is achieved, meanwhile, the temperature of the melt can be properly reduced, and the influence of temperature fluctuation is eliminated. Wherein the diameter D5 of the metering section 15 is 0.85-0.92D, and the diameter D6 of the mixing section 16 is 0.75-0.85D.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.