CN101913243B

CN101913243B - Venting extruder

Info

Publication number: CN101913243B
Application number: CN2010102720418A
Authority: CN
Inventors: 章华
Original assignee: WUXI JIANGNAN PLASTIC MACHINERY CO Ltd
Current assignee: WUXI JIANGNAN PLASTIC MACHINERY CO Ltd
Priority date: 2010-09-06
Filing date: 2010-09-06
Publication date: 2012-12-19
Anticipated expiration: 2030-09-06
Also published as: CN101913243A

Abstract

The invention discloses a venting extruder, which comprises a screw. The screw is arranged in a machine barrel. The screw comprises a feeding zone, a first metering zone, a venting zone and a second metering zone sequentially along the feed direction. An adjustable throttle valve is arranged between the first metering zone and the venting zone, and consists of two disks with slits, which are arranged on the machine barrel and are overlapped. The two disks with the slits can rotate relative to each other by taking the screw as the axis. When processing materials are changed or a machine head is replaced, by adjusting the slit area of the ring-shaped slit throttle valve, the venting extruder not only can guarantee the flow balance of the two metering zones and avoid the overflow of the materials and extrusion fluctuation, but also can make the free surface of gelatine always keep higher concentration gradient and improve the overflowing speed of gas from the gelatine so as to guarantee the quality of an extruded product.

Description

A kind of degassing extruder

Technical field

The present invention relates to the rubber degassing extruder, relate in particular to a kind of degassing extruder that adapts to multiple rapidoprint and different heads.

Background technology

The main working parts of degassing extruder is a vented screw; Second order vented screw commonly used is made up of feeding section, first metering section, exhaust section and second metering section; Sizing material gets into extruder from spout; Under the plastication of rotary screw, reach basic plastifying fusion state through shearing, compressing, sizing material begins to demonstrate the rerum natura of viscous state.After the material of basic plasticizing gets into exhaust section; Because the exhaust section screw channel is deepened suddenly, adds the swabbing action that exhaust outlet is connected to vavuum pump, pressure sharply drops to zero; Or even negative pressure state; At this moment melt original by compression gas and volatile substance, just in melt, foam, at the effect therapeutic method to keep the adverse qi flowing downward follicular rupture of exhaust section screw rod, the gas that overflows is taken away by vavuum pump from exhaust outlet.Melt through pump-down process is transported to second metering section work further plasticizing and mixing, and last under the squeezing action of screw rod, sizing material is extruded from head with certain pressure and temperature and formed goods.

The criterion of vented screw design is that the flow of first metering section and second metering section equates, i.e. Q1=Q2, otherwise can cause the exhaust outlet overflow or extrude wave phenomenon.The vented extruder screw of prior art can show reasonable exhaust effect man-hour and extrude quality can only adding to several kinds of elastomeric materials.But when changing more material or changing cross-head, will certainly destroy the flow equilibrium of two metering sections, thereby influence the degassing extruder operate as normal.

Summary of the invention

Technical problem to be solved by this invention provides a kind of novel vented extruder screw, and this screw rod can overcome because of changing extruded stock fluctuation or the overflow phenomenon that rapidoprint and head cause, and guarantees the operate as normal of extruder.

Degassing extruder of the present invention, it comprises screw rod, and this screw rod is arranged in the machine barrel, and screw rod comprises feeding section, first metering section, exhaust section and second metering section successively by feedstock direction, between first metering section and exhaust section, is provided with adjustable throttling.

Above-mentioned adjustable throttling is made up of two disks that are arranged on the band slit that overlaps on the machine barrel; These two disks are that axis relatively rotates with the screw rod; One of them is a fixed disc; Another is a movable disc, and this movable disk has stretches out the outer connecting rod of machine barrel, and this connecting rod connects the piston of a hydraulic jack.

The design of screw rod is exactly to fluctuate or the overflow phenomenon in order to overcome because of changing extruding that rapidoprint and head cause among the present invention, and screw thread no longer is set on the screw rod in exhaust section the place ahead, but the adjustable throttling of forming by two band slit disks that overlap.Get into the feeding section of vented extruder screw when sizing material after; Sizing material plastifies and transportation forward under the effect of screw rod rotation; Simultaneously because the shear action between screw rod and the sizing material makes sizing material in barrel, become melt; Sizing material needed can regulate according to the mobility status of sizing material during use through the slit on the choke valve before getting into exhaust outlet

The anglec of rotation of restricting element, thus the area that changes slit is big or small, has guaranteed the flow equilibrium of two metering sections.It is the realization that relatively rotates through between the choke valve that the slit area of two choke valves is regulated, and the angle of rotation receives the Stroke Control of hydraulic cylinder.

Get into the effect of the sizing material melt of exhaust outlet at external and internal pressure, make gas overflow from sizing material inside, get into second metering section through the rubber melt after the exhaust, the head moulding of extruder is passed through in further homogenize in second metering section at last.

When the present invention can or change head at the change rapidoprint; Through adjusting to the slit area of narrow annular channel choke valve; Not only can guarantee the flow equilibrium of two metering sections, avoid overflow and extruded the phenomenon of fluctuation, and can make the sizing material Free Surface remain higher concentration gradient; Accelerate gas from the inner speed of overflowing of sizing material, thereby guaranteed the quality of extruded product.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the axial sketch map of adjustable throttling and actuating mechanism thereof among Fig. 1.

The specific embodiment

As shown in Figure 1, a kind of degassing extruder of the present invention, this screw rod 1 comprises feeding section 2, first metering section 3, exhaust section 4 and second metering section 5 successively by feedstock direction, between first metering section 3 and exhaust section 4, is provided with adjustable throttling 6.Like Fig. 2; This adjustable throttling 6 is arranged on the band slit disk that overlaps on the machine barrel by two and forms; These two band slit disks can screw rod 1 for axis relatively rotates, one of them is a fixed disc, another is a movable disc; This movable disk has stretches out the outer connecting rod of machine barrel, and this connecting rod connects the piston of a hydraulic jack.Control the amount of spin of movable disc through moving of piston, thereby regulate the area that passes through that forms between the slit, play the effect of regulating flow.

The prerequisite of degassing extruder operate as normal is that the flow of first metering section and second metering section equates; The present invention can be through the adjusting to slit area 7 in the adjustable throttling; Thereby guarantee the flow equilibrium of two metering sections; Avoided overflow and extruded the phenomenon of fluctuation, and the adjusting of slit area 7 is to rely on two band slit disks to rotate the α angle each other to realize.

The invention provides a kind of thinking and implementation method of degassing extruder; Concrete application approach is a lot, and the above only is a preferred implementation of the present invention, should be understood that; For those skilled in the art; Under the prerequisite that does not break away from the principle of the invention, can also make some improvement, these improvement also should be regarded as protection scope of the present invention.

Claims

1. a degassing extruder comprises screw rod (1), and this screw rod (1) is arranged in the machine barrel (9); Screw rod (1) comprises feeding section (2), first metering section (3), exhaust section (4) and second metering section (5) successively by feedstock direction; It is characterized in that: between first metering section (3) and exhaust section (4), be provided with adjustable throttling (6), said adjustable throttling (6) is made up of two disks that are arranged on the band slit that overlaps on the machine barrel (9), and these two disks are that axis relatively rotates with the screw rod; One of them is a fixed disc; Another is a movable disc, and this movable disk has stretches out the outer connecting rod (8) of machine barrel, and this connecting rod (8) connects the piston of a hydraulic jack (10).