US3044623A - Apparatus for mechanical treatment of material - Google Patents

Description

July 17, 1962 H. BEHRENS 3,

APPARATUS FOR MECHANICAL TREATMENT OF MATERIAL Filed. July es, 1959 INVENTDP HEINZ BENRENS BY WM w. 3am,

ATTORN Er United States Pater 3,044,623 APPARATUS FOR MECHANICAL TREATMENT OF MATERIAL Heinz Behrens, 20 Deiselkulrnerweg, Schwarzenfeld, Oberpfalz, Germany Filed July 6, 1959, Ser. No. 825,014 7 Claims priority, application Germany Aug. 21, 1953 1 Claim. (Cl. 209-275) The present invention relates to apparatus for carrying out such method. As an example of such treatment reference may be made to the screening of materials, which are capable of being poured or are of a granular or pulverulent nature or in the form of a liquid suspension, or to the mixing together of different materials.

The invention provides such apparatus which is greatly superior to the apparatus heretofore employed, as regards the output achieved calculated in relation to the necessary dimensions of the apparatus employed, and also as regards accuracy of the treating process, for example the possibility of regulation of the process, or the like.

In the apparatus according to the invention, a rolling motion is imparted to the material by the application of vibrations to the receptacle containing the material. By suitable design of the receptacle a plurality of such rolling movements can be set up parallel to one another. If the receptacle accommodating a material to which a rolling motion is thus imparted is given the form, for example, of a screen, there is obtained in a very brief space of time a separation of the material into its components, which separation is more complete and eifective than that of previous methods for a given size of screen mesh. Similarly the combining or mixing of different substances is also considerably improved if vibrations are imparted to them to give them a rolling motion. Upon the addition of further substances there is obtained an almost ideally complete mixing, which is a considerable improvement on mixing methods known heretofore. The mechanical treatment, for example screening or mixing, may also be carried out step by step; a classification in various degrees of fineness may be obtained by a screening operation and a mixture comprising a plurality of initial materials by a mixing operation.

In the apparatus according to the invention troughlike channels are preferably employed which, by means of vibration generators, are given shaking movements substantially transverse to the axis of the channel. In these trough-like channels there are then produced two streams of materials rolling in opposition to one another.

A pure rolling motion of the material located in the channel may also be superposed on a conveying motion longitudinally of the channel. The conveyance of the material may take place by inclining the channel or by means of vibrations having a component in the direction of conveyance of the material. This latter device has the advantage of obviating differences in height between the intake and discharge points of the channel. In this connection it has been found that when superposing transverse and longitudinal vibrations the separation or mixing of material in the channel is considerably improved. In the screening of materials it is of particular advantage if the vibration components bringing about the conveyance of the material are directed obliquely to the surface on which treatment of the material takes place, for example at an angle of approximately 15 to the perpendicular at the screen surface, as in this case the vertical component of these vibrations greatly assists the screening operation. The vibrations can be imparted to the receptacle for the material under treatment by means of one or more vibraration generators, and the frequencies of the transverse vibrations producing the rolling streams of material and those of the vibrations effecting the conveyance and assistice Patented July 17, 1 962 ing the treating operation may be equal to or different from one another. By varying the frequency or amplitude of these vibrations it is also possible to, regulate the speed ofthe rolling action and the rate of conveyance as may be desired in a particular case.

Various forms of apparatus according to the invention are shown diagrammatically by way of example in the accompanying drawings in which:

FIGURE 1 shows diagrammatically how two rolling streams of material are formed in a channel;

FIGURES 2a and 2b show, respectively in cross section and in elevation, a curved channel which is perforated or is furnished with a screen attachment and is capable of being vibrated transversely to the direction in which. the material is conveyed;

FIGURES 3a and 3b show, respectively in perspective and in elevation, an inclined screen channel of the above kind for conveying coarse material under gravity; and

FIGURES 4a and 4b show a horizontal or substantially horizontal channel, to which there are applied simultaneously by means of one single unbalanced mass both a vibration component transverse to the direction of conveyance and a component in that direction.

Referring to FIGURE 1, there is' suspended between uprights 1 a channel 2, in which the material, in the form of two part-streams 4 and 5, has a gyratory and possibly also a helical advancing motion imparted to it by means of a shaking devicewhich is not shown in detail, for example a rotating unbalanced mass 3, which may be mounted on the end of an electric motor shaft (not shown).

FIGURES 2 to 4 show the apparatus according to the invention applied to screening operations, FIGURESQa and 2b being a cross-sectional view and a partial elevational view respectively of a channel 7 furnished with perforations 6. The reference numeral 8 indicates diagramatically the force producing the transverse vibrations.

The profile shown may naturally be modified according to circumstances, and in particular its shape in cross section may approach more or less a semi-circle.

In FIGURES 3a and 3b, which will be understood without further description, the channel is shown inclined towards the discharge end.

FIGURES 4a and 4b show in front view and in elevation a horizontal channel 9, to which a vibratory motion is imparted by means of a single vibration generator 12 which, as shown, is arranged above the channel 9, for example on the side flanges 10 and 11 thereof. The oscillation of the channel 9 is most satisfactory with the oscillator running at about 3000 cycles per minute. These vibrations have a component in the direction of the longitudinal axis of the channel and also transversely thereto so that each point of the channel is given a circular or elliptical movement: the channel is mounted on wooden or steel springs or bars 15, which are elastic in a plane perpendicular to the longitudinal axis of the channel 9.

For this purpose the vibration generator is arranged at an angle a to the perpendicular, so that the vibrations produced possess a vertical component in addition to their horizontal component. When the angle a is 0 the vertical component is zero, whilst the horizontal component perpendicular to the longitudinal axis of the channel is a maximum. The angle 0: can be varied between 0 and a maximum of but over the whole of this range the horizontal vibration component perpendicular to the channel axis is the maximum. Variation of the angle on does however vary the horizontal component in the direction of the longitudinal axis and when 0: equals 90 it is zero. Accordingly it is possible by Varying the angle a to vary not only the rate of advance of the material in the longitudinal direction of the channel, but also the height to which the material is lifted, so that it is readily possible to ascertain by experiment the optimum angle which is to be dependent on the material to be screened. The same is naturally also true to a mixing operation, the angle a being adapted to the materials being mixed. The two streams of materials rolling in opposition to each other are produced by arranging the axis of the unbalanced mass of the vibration generator 12 essentially perpendicularly to the horizontal and essentially in the center of the trough 9.

The form of the receptacle for the material is naturally not limited to a channel-like construction, and the surface employed for screening or mixing purposes may have any desired form; a channel-like form has, however, been found the most suitable.

If desired, a plurality of channels can be arranged side by side, and they may be given such vibrations as are necessary for screening or mixing by means of common vibration generators or generators which are coupled together in suitable fashion.

The channel may be either rigidly orresiliently constructed. It may have the form of a semi-circular or of a complete pipe, in which connection it is merely necessary to ensure that the channel formation does not prevent the occurrence of the gyratory part-streams of material mentioned above.

As vibration generating means there may be employed unbalanced devices or electro-magnetic or electro-static vibration means, and the vibration generators may be so arranged that instead of producing substantially regular vibrations the form of vibration itself is capable of being varied in many different ways. Particularly for mixing operations, but also if desired for screening purposes, the channel may be heated or electrically charged, heating or electrical charge may he allowed to take effect substantially only on the surface portions contacting the materials to be mixed or screened.

The two counter-rotating streams of material are established in the best manner with a channel having a semicircular cross-section, the diameter of which is between and 200 mm., whereby this trough-like receptacle is about 800 mm. long. The frequency of the vibration imparted to the receptacle is between and 75 periods per second, whereas the amplitude of such vibrations lies between 0.5 and 2 mm. The size of granulation of the material to be treated is between 0.3 mm. and 4 mm. and determines to some extent the frequency and the amplitude of the vibration together with other features of the material as humidity, temperature and other physical properties. But it is possible to a man skilled in the art without invention to adapt the frequency and amplitude of the vibrations to these properties of the material by simple alterations of the speed of the motor driving the unbalanced mass creating the vibrations.

Example A mixture of chamotte has been screened up to a size of 0.3 to 1 mm. in trough-like receptacles having semicircular cross-section. The diameters of these receptacles were about 25 mm. Eleven of such troughs have been combined to a solid combined construction with a length of 800 mm. This construction has been vibrated with a frequency of 48 periods per second and an amplitude of 1.2 mm. The throughput was kg. per hour and channel, Le. 1100 kg. per hour for the whole construction. The diameter of the screening holes was 1 mm. On the end of the channels only coarse material in small amount was present.

As will be apparent from the above description, the invention is not limited to the embodiments above described, in detail and illustrated in the drawings, and numerous modifications may be made without departing from the fundamental idea of the invention as defined in the appended claim.

The invention may in particular he applied to the conversion of ceramic substances into a thixotropic condition.

This application constitutes a continuation-in-part of my copending application Serial No. 450,867, now abandoned, filed August 19, 1954, and entitled Methods and Apparatus for Mechanical Treatment of Material.

What I claim is:

Apparatus for mechanically treating finely divided material comprising a horizontally extending elongate conduit of arcuate trough-like cross-section formed of deformable perforated material, resilient support means for supporting said conduit and enabling movement in a direction parallel to the longitudinal axis thereof and in a plane substantially perpendicular to the longitudinal axis thereof, said support means having a resilient restoring force, and a vibration generator operatively connected to said conduit including an unbalanced mass mounted for rotation about an axis for imparting vibrations to said conduit having a component transverse to the longitudinal axis of said conduit and a component parallel to the longitudinal axis of said conduit, the rotational axis of said unbalanced mass forming an acute angle with the longitudinal axis of said conduit to cyclically vibrate and deform the cross-section thereof.

References Cited in the file of this patent UNITED STATES PATENTS 807,423 Fern Dec. 12, 1905 1,989,777 Wettlaufer Feb. 5, 1935 2,143,610 Muller Jan. 10, 1939 2,398,455 Unger Apr. 16, 1946 2,682,3 8 Hurst July 29, 1954 FOREIGN PATENTS 897,231 Germany Nov. 19, 1953 904,761 Germany Feb. 22, 1954 489,210 Great Britain July 21, 1938

Images