DEVICE FOR TREATING MATERIAL MIXTURES

Abstract: The device comprises two conically shaped inner and, respectively, outer treating members (10, 30), which are rotatable relative one another and between themselves form a gap. Through this gap the material is intended to pass. The treating surfaces of the members (10, 30) are provided with bars (18, 70, 32) and grooves (17, 36). A cleaning member (60) is provided to clean the grooves (36) in the outer treating member (30). The cleaning member (60), therefore, is provided with wings, which are fitting into the grooves (36), and the member (60) is axially movable for variation of the depth of the grooves (36). A corresponding inner cleaning member (83) with wings (80) possibly can be arranged in the inner treating member (10).

Description: Device for treating material fixtures ϊhis invention relates to a device for.treating material mixtures. The device comprises two conically shaped outer and, respectively, inner treating members, which are rotatable relative one another. By means of these treating members different materials are mechanically processed, dispersed and/or mixed. Organic or inorganic fibre or particle materials, for example, can be dispersed in gaseous or fluid medium such as air, steam, water etc. Also chemicals such as colourants, bleaching agents, binding agents etc. can be admixed. Conventional mixing members comprise a number of variants comprising rotating and counter-rotating disc-shaped or conically shaped rotation bodies, which are provided with treating planes of different patterns comprising recesses and elevations, which produce the turbulence and agitation required for the function in question. When certain chemicals, for example binding agents are added to fibre mixtures,normally difficulties arise due to coatings on and clogging cf the different groove patterns of the treating members, which coatings and clogging are difficult to remove and after a certain operation time prevent functioning of the mixer. The mixer then regularly has to be taken out of operation for cleaning, which causes repeated stoppages and results in production disturbances. The only way of overcoming these interruptions has been to instal an extra number of mixing apparatuses, to which the fibre flow is transferred during the time when the clogged machines are cleaned and restored to operational state. This procedure is expensive both in respect of manual service and extra investments. The present invention eliminates these difficulties, in that the device is provided with mechanical cleaning members, which during operation of the mixer either continuously or intermittently remove material accumulated thereon and thereby maintain the mixer efficiency at maximum level. The principle of the invention can be applied to disc- -shaped as well as conically shaped treating planes. A conical embodiment of a device according to the invention is described in greater detail in the following with reference to the accompanying drawings, in which Fig. 1 is a longitudinal section of the device in two different embodiments A and B, Fig. 2 is a cross-section of the rotary and stationary treating surfaces, with an axially movable cleaning member placed in the stator, embodiment A, Fig. 3 shows an embodiment according to Fig. 2, but with cleaning members inserted also into the rotary treating member, embodiment B. The device according to the embodiment shown comprises a rotor 10 supported by an axle 12 mounted in an axially movable bearing housing 13 and supported at the driving end by an axially movable gear clutch 16, which is rigidly connected to a driving motor 20 via the shaft 22 thereof. The rotor 10 is enclosed by a stator 30, which comprises longitudinal bars 32 and intermediate grooves 36 and is rigidly secured in a stand 40 enclosing the device. Said stand supports by an upper portion the driving motor 20. The bearing housing 13 is supported by a yoke bearing 44 connected to the lower portion of the stand. The rotor 10 is axially movable by means of a- control device 90 atttached to the yoke bearing 44, which device can adjust the bearing housing 13 to the desired axial position and thereby vary the gap between the rotor 10 and stator 30. The fibre material to be treated is supplied through a pipe line 50 opening at the smaller end of the conical rotor 10, where the material by means of a carrier 11 mounted on the rotor is slung out to the inlet opening 14 between rotor 10 and stator 30. The fibre material is caused by bars 18 (Fig. 2) or 70 (Fig. 3) on the rotor 10 to assume a rotation speed, which is substantially the same as that of the rotor, for example 3000 rpm at 50 cps and 3600 rpm at 60 cps. This rotation acts on the fibre mixture with centrifugal forces, which at the example cited amounts to the magnitude 2500-4000 g, by which forces the fibre mixture during its passage through the mixer is pressed against the enclosing stator 30. Owing to the high centrifugal force, the fibre mixture is concentrated to a considerably higher density in the fibre layer closest to the stator 30 and the grooves 36 arranged:, in the longitudinal direction. The air following along with the fibre suspension to the greatest part goes off in the grooves 17 of the rotor 10 between the rotor bars 18,70 out to the outlet 15 of the mixer. The concentrated fibre mixture closest to the conically shaped stator surface 30 with the angle ( is applied with a discharging force in the direction to the outlet 15 corresponding to the - -sine component of maintained centrifugal force. The chemical addition required for the process is supplied either at the inlet 50 or directly between rotor and stator near the feed opening 14 via a number of supply nozzles 3 uniformly distributed over the inlet surface. The chemical supplied, which can be in liquid or aerosol state, is thereby spraid instantaneously about the circum¬ ference of the rotor 10 and by maintained centrifugal force slung out to the concentrated fibre layer of the mixer stator where it is absorbed at the passage of the material through the mixer. In order to prevent the stator grooves 36 in the manner described from being filled with fibres and, for example, added binding agent, the stato 30 is provided with an axially . movable enclosing outer cleaning member 60, which is provided with wings 62 (Fig. 1 A, Fig. 2). Said wings 62 are adapted to partially fill the grooves 3β between the rigidly secured stator bars 32. When this outer cleaning member 60 is moved axially in the direction to the outlet 15 of the mixer, the inner flank of the wings 62 is moved radially inward to and past the inner surface of the rigidly secured stator bars 32, whereby the grooves 36 between the bars 32 are filled entirely with the movable wings 62. Fibre and binding agent deposits accumulated in the grooves 36 thereby are pushed out to the gap between the rotor 10 and stator 30 a where they by action of the rotor bars 18 are broken off from the wings 62 and removed with the treated material. The outer cleaning member 60 with wings 62 thereafter is moved back to the inlet of the mixer, whereby the groove space 36 is restored, free from previous coatings. The movable cleaning member 60 at the example cited is caused to carry out its reciprocatory movement by means of a pressure medium, which is supplied alternatingly to ring pistons 64 and 66,supporting the member,through the passageways 67,68. The frequency of the movement is adjusted to demand for maintaining maximum mixing effect. If required, a Corres¬ ponding cleaning device can be applied also on the rotor 10 where an axially movable inner cleaning member 80 is attached to similar ring pistons 8l and 82, which by supply of pressure medium via a swivel 84 mounted on the axle 12 and passageways 85 and 86 in the axle " is caused to carry out a reciprocatory movement. The frequency is also here adjusted to demand. This embodiment is shown in Fig. 1 B. The invention, of course, is not restricted to the embodiment shown, but can be varied within the scope of the claims.

Claims: Claims 1. A device for treating material mixtures, comprising two conically shaped inner and, respectively, outer treating members (10,30), which are rotatable relative one another and between themselves form a gap for the passage of the material from an inlet (50) to an outlet (15), where the treating surfaces of the members (10,30) are provided with longitudinal bars (18,70,32) and inter¬ mediate grooves (17 . 36), c h a r a c t e r i z e d i n that the bottom of the longitudinal grooves (36) in at least the outer treating member (30) is defined by a cleaning member (60) provided with wings (62), which are fitting ir. between the bars (32) of the treating member (30), and the outer cleaning member (60) is axially movable for variation of the' ^ depth of the grooves (36). 2. A device as defined in claim 1, c h a r a c t e r ¬ i z e d i n that the outer treating member is a stator (30), and the inner treating member is a rotor (10). 3. A device as defined in claim 1 or 2, c h a r a c t ¬ e r i z e d i n that an inner cleaning member (83) also provided with wings (80) is arranged to co-operate with the inner treating member (10), in that its wings (80) are fitting in between the bars (70) of the inner treating member (10), and the inner cleaning member (83) is axially movable. 4. A device as defined in any one of the preceding claims, c h a r a c t e r i z e d i n that the cleaning members (60,83) are supported by ring pistons (64,66,81,82) and moved by means of a pressure medium. 5. A device as defined in any one of the claims 2-4 where the material inlet (50) is located centrally at the narrow portion of the rotor (10), c h a r a c t ¬ e r i z e d i n that the rotor is provided with a carrier (11) intended to sling the material to the gap opening between the rotor (10) and stator (30). 6. A device as defined in claim 5, c h a r a c t e r ¬ i z e d i n that a device for the supply of a treating agent is located in the material inlet (50). 7. A device as defined in any one of the claims 2-5, c h a r c t e r i z e d i n tha€ a device for the supply of treating agent -is located in the stator (30), which supply device has the form of a number of nozzles (34) opening in the gap near its inlet opening (14).

Inventors: REINHALL ROLF B, REINHALL, ROLF, B.
Applicants: SUNDS DEFIBRATOR, SUNDS DEFIBRATOR AKTIEBOLAG
Application year: 1989
Main classification: B01F7
IPC codes: B01F5, B01F7