HU194072B - Apparatus for producing grinds particularly micro ones - Google Patents

Abstract

Appts. comprises milling cylinders provided with vibrating rods. A collector chamber is located at one end of each cylinder, separated from the grinding space by a grid. The collector chamber contains a regulating mechanism which enables the prodn. of specified size distributions. - The regulating mechanism consists of two concentric rollers in touch with each other and having openings in their surfaces. These openings are identical and may be arranged so that one is located over the other. The outer cylinder is fixed, while the inner cylinder may be rotated about its longitudinal axis. - The openings are bounded by a slanting, straight line, and as seen from this slanting, straight line, by a concave curve. The openings become narrower towards the top and the bottom.

Description

FIELD OF THE INVENTION The present invention relates to apparatus for producing millings, in particular micro-mills, such as fillers, glazings, carriers, filtering and diluting products, and the like, comprising one or more vibrating rod milling rollers and at least one end chamber a particle size regulator having a pivotable, concentric cylindrical pivotable pivotable, overlapping, reciprocating apertures, which are pivotable, overlapping with one another, and having a concentric cylindrical pivotable about one another.

Many industries require the use of micro-mills for various purposes. These are predominantly carbonate-type and natural silicate-type products and have a desirable particle size of generally 100 µm, often below 30 µm. However, such grinding fineness materials can only be produced by very expensive equipment or technologies (dry or wet fine grinding and wind grading; or hydrocyclone grading, etc.), which is why the cost of these products is high and often difficult to obtain. A further problem is that while the known equipment and technologies can control the fineness of mineral grinds, the composition of the grain structure cannot be influenced. the paper, rubber, paint, fill, glaze, carrier and diluent products, and the canning industry require products with a defined particle size and composition.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a matrix which is primarily intended for the production of mineral grinds, in particular micro-mills, which, on the one hand, produce a desired particle size and, on the other hand, a specific grain structure.

The invention is based on the discovery that a vibrating mill known per se can be adapted to provide the required grinding fineness and mesh structure by conveniently forming the control mechanism which is part of it.

Based on this discovery, the object of the present invention has been solved by an apparatus having one or more vibrating rod grinding cylinders and a blocking chamber connected to the end of at least one grinding roller having a control mechanism for controlling the particle size of the mill. it has rotatable, concentric, stationary, concentric cylinders with converging and overlapping apertures in its periphery, the apparatus of which is that the cylinders have an oblique line at one side and an opposite line at their opposite sides; they have narrowing openings at the top and bottom, which are bounded by a concave curve when viewed from an oblique straight line. Micro-grains are defined as grains that are finer than ΙΟΟμτη.

An embodiment of the apparatus is characterized in that the apertures are approximately the same height as the rollers. It is further preferred that the apertures are bounded at the top and bottom by a straight, preferably horizontal, section.

According to another embodiment of the invention, the lengths of the bottom and top of the openings are smaller.

as a tenth of the height of the openings, the lower section preferably being less than the upper section.

In another embodiment of the apparatus, the arcuate side defining the apertures is formed by a downward spiral curve segment.

Preferably, the outer cylinder is in a fixed position and only the inner cylinder is pivotally formed, the oblique straight side delimiting the apertures from a top-down acute angle with the components of the cylinders in the same direction of rotation.

Thus, in a further embodiment, the radius of curvature of the apertures is greater than the radius of curvature of the aperture above the midpoint of its height. A very advantageous feature of the invention is that the highest point of the cross-section is spaced below the upper end of the apertures before the total closure position, preferably at about 75% closure. It is also desirable that the grinding chamber (s) of the grinding roller (s) and the chamber of the chamber (s) are separated by a grid of rods.

The apparatus of the invention generally comprises two elastic stops located one above the other; it has a milling roll kept on a rack; the upper bobbin roller being fed at its lower end with a delivery chamber having a dispensing head, and at the other end having a regulating device which is connected to a feeding chamber formed at one end of the lower milling cylinder by means of a jumper . It is also desirable to have an axis of the device connected to a drive motor with eccentric weights for causing the rods to vibrate in the grinding rollers.

The invention will now be described in more detail with reference to the accompanying drawings, which show a preferred embodiment of the apparatus and a preferred embodiment of the control device. 1 is a schematic side view of an embodiment of a grinding apparatus according to the invention;

Figure 2 is a larger scale of detail marked A in Figure 1;

Figure 3 is a larger sectional view taken along line B-B in Figure 2;

4-8. Figures 3 to 5 show some typical operating states of the outlet of the control mechanism of a known vibrating mill; Figures 5, 6, and 8 illustrate the rollers of the control device in an extended position; Figures 3 to 5 show some typical operating states of the control opening of the device according to the invention;

Figures 10, 11, 12 and 13 illustrate the positions of the control device in an expanded position.

The apparatus shown in FIG. 1 has grinding cylinders 1 and 2 which are superimposed and have longitudinal geometric center axes parallel to each other. A dispensing head 3 is connected to one end of the upper grinding roller 1, and a delivery head 4 is also connected to the left end of the lower grinding roller 2. The apparatus as a whole has a stand 5, which holds the grinding rollers 1,2 by inserting the rubber stops 7.

To operate the device, it is connected to a drive motor (not shown) and (also not shown).

194.072 zolt) 6 drive shafts with eccentric weights. The connecting means 8 are arranged between the grinding rollers 1 and 2 and rest on the rubber stops 7.

The grinding rollers Ag 1 and 2 are connected to one another via a connecting line 8 in the region opposite to the pickup and delivery heads.

The grinding rollers 1 and 2 are provided with a blocking chamber 14 at each end and a supply chamber 14a at the other end. In Fig. 1, the above-mentioned dispensing head 3 extends into the upper part of the supply chamber 14a on the left and the dispensing head 4 protrudes from the lower part of the lower blocking chamber 14 (belonging to the grinding cylinder 2) (Fig. 1).

Figure 2 shows a larger scale of the bottom chamber 14 of Figure 1 and the section of the grinding rollers 2 connected to this chamber. The grating space 11 of the grinding roller 2 and the grating space 15 of the compression chamber 14 are separated by a grid 10 formed from the grid bars 10a. In Fig. 2, the gaps between the bars 10a are denoted by reference numeral 10b and for the sake of clarity, only a portion of the bars are shown. The lattice bars 10a are held together by a lattice retaining ring 13 to form a lattice structure 10.

In the grinding chamber 11, as is known in the art, there are milling rods 12 parallel to the constituents of the grinding cylinder 2, which fill approximately 65% of the grinding chamber all. The grinding roller 1 is of the same construction as the grinding roller 2.

The regulating device 16 has two stationary concentric cylinders (1 also in Fig. 3), of which the outer cylinder 17 is in a fixed position and the inner cylinder 18 about its own longitudinal central geometrical axis X, which is vertical, is indicated by the arrow in Fig. 3. can be rotated. There is, of course, practically no gap between the two rollers, the rolls being close to each other, the gap between them being drawn in Figure 3 only for the sake of clarity.

As shown in Figures 2 and 3, the outer cylinder 17 has an opening 19 in its periphery and an opening 20 in the peripheral of the rotatable inner cylinder 18, which are exactly the same in shape and size, and are in the same position. Turns 18 rolls to overlap each other. In this way, the opening 19 of the outer cylinder 17, which is also the outlet of the regulator 16, can be completely rotated by rotating the inner cylinder 18, but can also be fully opened by covering the openings 19, 20. Intermediate positions between full opening and full closing position can influence the particle size and grain structure, as will be explained in more detail below, but first, in order to demonstrate the beneficial effects of the present invention, FIGS. Figures 3 to 5 illustrate the limitations of achieving a desired particle fineness with a conventional vibrating mill control mechanism.

The known control device 21 shown in Figure 4 also has a stationary outer cylinder 22 and an inner cylinder 23 which is pivotable about a vertical longitudinal axis X. These openings, which are also congruent and rotatable with one another, are oblong-triangular in shape and are positioned such that their short sides extend above and the acute angles of the triangles are below; the lowest point of the opening '22a is designated by the reference letter c. The hatched area t detects an opening size corresponding to an intermediate position.

5-11. Figures 4 to 5 show the cylinders 22, 23 of the control device 21 of Figure 4 extending and superimposed on one another, however, the cylindrical bodies are offset relative to each other in the figures and their openings 22a, 23a are differently overlapping accordingly. they are different. Figure 5 shows the entire opening position, the openings 22a, 23a of height M practically overlapping each other, the plated area t _t represents the maximum possible cross-sectional flow. In Figure 6, the hatched area tj has a closure position of 50%, the lowest point pi of which is located at a distance above the lowest point c of the opening 22a. THE

In Fig. 7, the hatched area t ₃ corresponds to a 75% closure position, with the lowest point p ₃ displaced from point c, the relation hj h _{3 being} , and of course the relation t ₃ t ₂ t. Otherwise, the distance hj.hj ... from the full opening to the full closing state increases linearly. (Figures 5-7). Finally, Figure 8 illustrates the state of complete closure, in which the aperture 22a formed in the skirt 22 is completely closed by the skirt of the inner cylinder 23 (also Figure 1 in Figure 4).

Figure 9 shows a larger scale of the control structure 16 of the device according to the invention, while Figs. 5 to 8, the cylinders of the control mechanism are shown in an extended position, stacked on top of each other, illustrating the typical closing and opening positions shown in FIGS. corresponding to FIGS.

9-13. 4 through 8, the openings 19, 20 are substantially different in shape from those of FIGS. Figs. Referring to Figure 10, the reference numbers and symbols for defining the apertures are also shown. Otherwise, Figure 9 shows a complete opening state.

In Fig. 10, the direction of rotation from the inner cylinder 18 is indicated by an arrow f, the arrow E being the side of the aperture body -19, 20 formed by a long oblique line 30, which forms an acute angle β with the vertical (β may be in the range of 5-20 °) and incline in the same direction of rotation f. Opposite the side 30, the openings 19, 20 are delimited by a curved side formed by a concave curve in the direction of the arrow f representing the direction of rotation. The openings are bordered by a horizontal straight section 33 at the bottom and a horizontal horizontal section 32 at the top. The length of the latter lj is greater than the length h of the lower boundary section 33. The shape of the arcuate boundary line segment 31 corresponds to a spiral curve segment whose radius decreases from top to bottom; this is illustrated in Fig. 10 by plotting the radius R _{t of} the curve segment below the point F in the midpoint of the opening 19 at height M, i.e. from the bottom at the height of MX2, and the radius Rj of the curve section above the point Fi. ₁ <R is _the relation between these radii. The lowest point of the outlet 22 is designated by the reference letter C. The openings 19, 20 are shown in Figs. Figures 3A and 4B illustrate clearly the bottom and top.

1-3. 9-13. The apparatus according to Figs.

The material to be milled is fed into the apparatus from the direction of the flowrate shown in FIG. We start it with the eccentric 6 axes

194,072 engages a drive motor (not shown), whereby the grinding rods 12 (Fig. 2) in the grinding cylinders 1, 2 are vibrated and the material passing through the apparatus in the direction of the arrows b is constantly crushed by the impulse force exerted by them.

Each control chamber 14 is provided with a control device 16, which passes through the outlet opening of the chopped ground material into the connecting line 9 and from there to the milling cylinder 2 and, as shown by the arrow in FIG. via a delivery head 4 connected to the lower end of a blocking chamber 14 for a grinding cylinder. Depending on the outlet cross-section I of the outlet 19 (highlighted by hatching in FIG. 1), the material will be shorter or longer in the grinding space 11, otherwise it will pass through the gaps 10b of grid 10 in FIG. 15 to the obstruction space. On the other hand, the shape of the outlet 19 influences the grain structure of the mill, as shown in FIGS. 5 to 8 and FIGS. Figures 4 to 5 show a comparison with a conventional structure.

In Figures 9 and 10, the outlet opening 19 is shown in its full opening state, with a maximum flowrate I _t . Fig. 11 illustrates a 50% closure state, the corresponding hatched flow-through cross-section I ₂ is clearly smaller than the hatched area I _{t in} Fig. 10. The lower point Pj of the outlet 19 is upwardly Hj relative to the position of Fig. 10. The hatch-outflow I ₃ cross section corresponding to the 75% closing position shown in Figure 12 was further reduced. with the lower point P _{2 of the} outlet opening I ₃ <I ₂ and the outlet opening 19 higher than where the point P 1 (Fig. 11) is located, i.e. H ₂ <H ₂ . ι Now comparing Figure 6 with Figure 11, it is clear that otherwise, with the same or substantially the same geometric dimensions, at 50% closing position, the size Hj is significantly smaller than the size hj, i.e. the total opening position moving from the bottom to the entire closing position, the upward displacement of the lowest point of the flow cross-section according to the invention is significantly smaller than with the conventional control device. This factor is extremely advantageous because an increase in the size of H and H, respectively, results in relatively more fractions of the powder being discharged through the outlet than is desirable. Namely, in the grinding space 11 of the grinding roller 2 (Fig. 2), and consequently in the blocking space 115 of the compression chamber 14, the granular ground material is located so that the finer fractions are at the bottom and the coarser fractions are at the top. So if the Hj value (Figure 11) is relatively small, several fine particles below will leave the device, and vice versa: if the gap distance is relatively large (Figure 6), some of the fine particles cannot leave, but at the top, relatively larger particles are discharged, so that they do not have sufficient time to get to the desired grinding flux. This tendency applies to all stages of the closure towards the complete closure position: when comparing Figures 7 and 12, it can be seen that h ₂ <H ₂ , thus leaving more coarse fractions at the 75% closure position in the conventional solution. away from the finer.

As shown in Figure 12, the upper portion of the outlet opening 19 closes shortly before the 75 position: the degree of upper closure at the 75% position is indicated by a m letter. The existence of this upper closure is extremely advantageous because, as already mentioned, the coarser fractions are located above, so that the upper closed section of height m, which is constantly increasing towards the full closure, retains some of the coarse fractions in the grinding space, This allows relatively fine particles to leave. This is one of the most important prerequisites for superfine grinding - that is, for the production of micro-mills. By way of comparison, it should be noted that as long as FIGS. 9 through 13, vibratory mills equipped with a control device according to FIGS. The apparatus having a control structure according to Figs. In addition, by adjusting the lower and upper closure levels between the closure friction positions, the grain structure of the meal can also be influenced. The grading device of the device of the present invention thus influences the filling level of the baffle or grinding chamber and the milling process in such a way as to prevent the coarse particles generally located at the top during vibration from passing to the next milling cylinder or the final product ring. Because we can prevent at least a portion of the larger-than-average particles from escaping from the apparatus, it is possible to control the grain size of the powder and to narrow the Gaussian curve of the powder or to rotate the tip of the curve to the desired direction, coarse or fine. .

It will be appreciated that the precursor raw material must be prepared in a manner known per se before being fed to the apparatus of the invention. The preparation includes the operations of pre-crushing and, if necessary, drying. The material from the grinding apparatus according to the invention is also separated into fractions in a manner known per se. Separation can take place with wind turbines in series or, with wet milling, hydrocyclones. Generally, the powder is separated into two or three grain classes, and the desired fractions are prepared by means of mixing screws, or the individual fractions are treated as special mills. For the production of three grain fractions, two grain separators are generally capable of producing mineral flour within the limits of any particle size within the range of 1 to 100 microns.

The following are some examples of industrial applications of the grinds obtained by the present invention.

The device of the present invention is a milled and graded zealir with a grain size of 50 µm and a directed mesh structure. The filler can be used at a retention value of 79-75% by preparing 1000 kg fine offset paper with 15% ash from 970 kg of bleached cellulose and 180 kg of zeolite flour - a total of 1150 kg of dry matter.

zeoLit grit with a grain size of less than pm can be used to produce paper zeolite glaze pigment according to the following formula:

40% zeolite meal

5% synthetic pigment binder,

194 072

15% oxidized starch,

2% dispersant,

38% water

100% total 100% glaze suspension; which is used to decorate.

milled and graded to a particle size of less than pm, CaC0 ₃ controlled directional filler can be used in the paper industry with 70 to 80% retention under neutral adhesive conditions, e.g. by blending 970 kg of bleached cellulose with 220 kg of CaCO ₃ and producing 1000 kg of base paper with a 15% ash content from a total of 1190 kg of dry matter.

μη \ can be used to form a granulated and graded, controlled particle size CaCO ₃ , glaze pigment for paper coating, to obtain a matt slurry providing a matte coating surface by mixing 50 parts by weight of CaCO ₃ with up to 100 parts by weight of kaolin. glaze binder, of which 60% is starch based, 40% is synthetic and must be diluted with water to a dry matter content of 60%.

Graded silica powder with a particle size of less than μιη can be used in the paint industry to make a pigment paste, e.g. according to the following recipe:

% fine color pigment,

10% silica powder carrier,

65% to 70% 3% solution of methyl hydroxyethyl cellulose.

The coloring pigment paste thus prepared is well stored, has a slightly fixotropic property, and has good coloring properties.

With the apparatus of the present invention, a directed, screened particle size grit with a particle size of less than 10 µm in the paint industry for the production of powder paint, e.g. apply according to the following formula:

87.0 parts by weight of wheatgrass powder 10.0 parts by weight lithopone 2.5 parts Hansagelb 10 G 0.5 parts Bezlin blue

100 parts by weight of green, high coverage powder paint.

Directed-grain CaCO ₃ milled to a grain size of 60-80 µm as a filler in the rubber industry e.g. is used to 85 parts prepared gumlmasszát mixed with 15 parts of CaCO ₃ mass, and filled gum mass is processed further.

The advantageous effect of the invention is as follows:

It is known that in certain industries, e.g. In the paper paint and rubber industries, the particle size distribution of the filler material must contribute to a large number of technological and economical conditions, ie it must have the optimum particle size distribution required for its chemical and physical properties, which is one of the important conditions. It is also desirable that the filler be so-called. oil number should be low. With such fillers, e.g. with the minimum use of binders and pigments in the paint industry, the desired coverage is achieved.

Due to the fact that the device according to the invention is capable of producing industrially fine-grained, controlled-grained, very fine-grained mineral micro-minerals, there is only a minimal proportion of mineral grains in the application, which interferes with the application technology. improves, and sometimes the cost of production decreases. A further advantage of the present invention is that a multi-grain product can be produced at the same time from the same mineral base. In paper applications, the effect of the guided particle structure has a favorable effect on the retention of the mineral fillers used. The controlled and directed particle structure makes the bonding properties of the dyes on the substrates more specific. Knowing the exact structure of the mesh, the ratio of carrier, binder and colorant can be more accurately determined. The requirements for optimum filler ratio, minimum pigment ratio, maximum opacity for dye mineral filler mills are best met by grinds that do not contain particles larger than 20 or 40 micrometres and contain only a minimal amount of 2-3 micrometers smaller particles. (Significant presence of such small granules results in higher oil yields and, consequently, increased binder demand, which in turn degrades the economics of the product.)

Grinds having such properties can be produced without the aid of the device according to the invention.

The advantage of strict adherence to the upper particle effect is that the binder remains in dispersion and does not settle - while providing the lids.

The invention is, of course, not limited to the embodiment of the apparatus as detailed above, but may be practiced in various ways within the scope defined by the claims.

Claims (11)

Apparatus for producing powder, in particular microfibre, comprising one or more vibrating rod grinding cylinders and at least one blocking chamber connected to the end of the grinding roll, comprising a control device for controlling the particle size of the grinding, having a common vertical axis, having cylindrical concentric cylinders with coincident and overlapping apertures in its periphery, characterized in that the cylinders (17, 18) have an oblique line (30) on one side and an oblique line (30) on their opposite side. they have narrowing openings (19, 20) at their top and bottom, which are delimited by a concave curve (31) viewed from an oblique line (30). Apparatus according to claim 1, characterized in that the height (M) of the openings (19, 20) is approximately the same as the height of the rollers (17, 18). Apparatus according to claim 1 or 2, characterized in that the openings (19, 20) are delimited by a straight, preferably horizontal, section (32,33) at the top and bottom. 4. Apparatus according to claim 3, characterized in that the openings (19,20), top and bottom, addition flanking portions (32, 33) has a length (lj, l) _is smaller than the openings (19, 20) the height ( M) is one-tenth of the length of the spade (33) (Irish) preferably less than the length (lj) of the upper section (32). 194 072 5. Apparatus according to any one of the preceding claims, characterized in that the arcuate side (31) delimiting the openings (19, 20) is formed by a downward spiral curve section (Rj, Rj). 6. An arrangement according to any one of claims 1 to 3, characterized in that the outer cylinder (17) is fixed and only the inner cylinder (18) is pivotable, with the inclined straight side (30) defining the openings (19, 20) with the direction of rotation. (f) closes a top-down acute angle (β) in the same direction with the components of the rollers (17, 18). Apparatus according to Claim 5 or 6, characterized in that the arcuate aperture curve (31) - section radius (Rj) above the half-height of the apertures (19, 20) is greater than the curve below it. Radius of section (31) (Rí). 8. Apparatus according to any one of claims 1 to 3, characterized in that, prior to the complete closure position, preferably at another 75% closure, the upper part of the flow cross section (T ₃ ) The opening (P ₃ ) is located at a distance (m) below the upper end of the openings (19, 20). 9. Apparatus according to any one of claims 1 to 4, characterized in that the grinding chamber (11) of the grinding roller (s) (1, 2) and the stopping chamber (15) of the chamber (14) are separated by a grid (10) of rods (10a). . 10 2) is; a feed chamber (14a) having a feed head (3) at the inlet end of the upper grinding roller (1) and a blocking chamber (14) having a regulating device (16) at the other end which interconnects the feed chamber (14a) a blocking chamber (14) having a lower end (4) connected to it. 10. Apparatus according to any one of claims 1 to 4, characterized in that two grinding cylinders (1) held on a rack (5) by means of two superimposed resilient stops (7), Apparatus according to any one of claims 1 to 10, characterized in that the drive motor is coupled with an eccentric weight, j; has a shaft (6) for vibrating the rods (12) arranged in the grinding rollers (11, 2).