Parallel co-rotating intermeshing twin-screw extruder

Abstract

The invention discloses a parallel co-rotating intermeshing twin-screw extruder used for compounding or compounding extrusion of plastic materials such as plastic. The parallel co-rotating intermeshing twin-screw extruder comprises a parallel co-rotating intermeshing twin-screw continuous compounding or compounding extrusion device, a tail side transmission case, a head side transmission case, and at least one motor; the parallel co-rotating intermeshing twin-screw continuous compounding or compounding extrusion device comprises an integral or a combined type housing; the housing comprises two cavities which are parallel in longitudinal direction and are intercross along longitudinal direction; each cavity is provided with a pair of co-rotating intermeshing screws, one of the co-rotating intermeshing screws is protruded out of the head end and the tail end of the housing respectively, the forward protruded end is driven to rotate by the head side transmission case, and thrust supporting of the backward protruded end is realized by the tail side transmission case reelingly in longitudinal direction i.e. in axial direction; the other co-rotating intermeshing screw is protruded out of the tail end of the housing, and thrust supporting and driving of the backward protruded end is realized by the tail side transmission case reelingly in longitudinal direction i.e. in axial direction, so that torque density is capable of exceeding 10Nm / cm<3> economically and serviceably, and is capable of exceeding 20Nm / cm<3> significantly.

Description

Technical field: [0001] The invention relates to a parallel co-rotating intermeshing twin-screw machine for compounding or compounding and extruding plastics and other plastic materials, in particular to a parallel co-rotating intermeshing twin screw machine of a high-torque parallel co-rotating intermeshing twin screw machine Continuous compounding or compounding extrusion equipment and related drive components. Background technique [0002] There are more than one types of intermeshing twin-screw equipment for processing plastic materials such as plastics, depending on whether the two screws are parallel or non-parallel and the direction of rotation is the same or different. Parallel and co-rotating intermeshing twin-screw machines belong to the most important category at present. It includes parallel co-rotating intermeshing twin-screw compounder (Parallel co-rotating intermeshing twin-screw compounder) and parallel co-rotating intermeshing twin-screw extruder. The former is ...

AI Technical Summary

Problems solved by technology

In fact, in order to ensure the uniform load of the gear teeth, the gear manufacturing needs to include the modification of the tooth direction and even the tooth profile, which can increase the cost by at least 3 times. Gear Manufacturers Association Standard) 10 and a half to 12 and a half or DIN (German Industrial Standard) 6 to 4 meshing precision, that is, gears, shafts, bearings and housings of corresponding precision levels are required to achieve, which is compared with the so-called "standard" "Accuracy grade" is DIN7 grade (corresponding to AGMA9 and a half or Chinese national standard grade 7), the cost of the rear transmission box is at least 3 times higher, making the high-torque traditional parallel co-rotating intermeshing twin-screw machine very expensive

[0053] Second, the driven gear on the shorter overhanging shaft itself is a high-load final gear, and the smaller pitch circle diameter causes its wear time life to be insufficient in the "one-to-one" gear transmission. Compared with "one-to-one" gear transmission, the "many-to-one" gear transmission has double (2-3 times) increase in the number of gear teeth meshing per revolution, that is, the double (2-3 times) increase in wear time and shortened life expectancy. , making the gear conspicuously less durable

In order not to reduce the life, the load on the tooth surface must be reduced, thereby reducing the torque density (M / a 3 ), which becomes the prior art high torque density (M / a 3 ) The technical contradiction of the power distribution shaft (wheel) system and another significant technical shortcoming

[0054] Thirdly, it is known that the pitch circle diameter of the gears on the shorter outrigger shaft is severely limited by the center distance a and is smaller, and due to the space occupied by the longer outrigger shaft, it is reasonable to arrange symmetrically or roughly symmetrically Described " many to one " can only reach " three to one " at most, so screw rod 1 has limited described prior art high torque density (M / a 3 ) The power distribution shaft (wheel) system continues to increase the torque density (M / a 3 )

[0055] Fourth, so far, the continuous improvement of the torque bearing capacity of the two outstretched shafts (as the shaft itself) has been achieved by continuously replacing them with special steels with higher and higher heat treatment strengths (—— two screw rods similar situation), which leads to a substantial increase in the cost of steel and / or tooling for the two outrigger shafts and is yet another reason why high torque tailside transmissions become expensive

However, the adoption of the two synchronous transmission gears requires high gear transmission accuracy due to the requirement of load sharing, that is, the drive components are more expensive at this time

[0091] In summary, the traditional parallel co-rotating intermeshing twin-screw machines for compounding or compounding extrusion of plastic materials such as plastics, and the anti-traditional ones suggested by German patent applications DE2040065-A, DE102006060739-A1 and DE102008029130-A1 Parallel co-rotating intermeshing twin-screw machines, due to the inherent technical defects of parallel co-rotating intermeshing continuous compounding or compounding extrusion devices and their drive components, it is difficult to economically and durably achieve large torque densities (M / a 3 ), that is, 10Nm / cm 3 Above, and continue to increase the torque density (M / a 3 ) For the complete machine that adopts the drive assembly of the prior art power distribution shaft (wheel) system and the integral screw or the downstream modularized screw of the processing section, the complete machine faces three structural bottlenecks or a fatigue strength bottleneck—the structural bottleneck That is, the bottleneck of the gear transmission capacity of the power distribution shaft (wheel) system, the minimum outer diameter d of the backward overhanging section of the two screw rods and the forward overhanging section of the two overhanging shafts R Minimum outside diameter d on bottleneck, longer outrigger shaft LA Bottleneck, the fatigue strength bottleneck is the strength obstacle formed by the concentration of tensile stress at the dangerous section, which leads to a significant decrease in the fatigue limit; while continuing to increase the torque density (M / a 3 ) For the drive assembly of the prior art power distribution shaft (wheel) system and the complete machine of the full-length modular screw in the processing section, at least the drive assembly faces three structural bottlenecks or one fatigue strength bottleneck—namely The bottleneck of the gear transmission capacity of the power distribution shaft (wheel) system, the minimum outer diameter d of the forward extension section of the two extension shafts R Minimum outside diameter d on bottleneck, longer outrigger shaft LA Bottleneck, the fatigue strength bottleneck is the strength barrier formed by the concentration of tensile stress at the dangerous section, which leads to a significant decrease in the fatigue limit

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