RU2261150C2 - Screening device - Google Patents

Abstract

FIELD: separating solids from solids.

SUBSTANCE: screening device comprises main frame, auxiliary frame mounted on the main frame, screen concave mounted on the auxiliary frame for permitting adjusting common angle of screening and having charging end for receiving loose material and opposite discharging end for discharging remainder unscreened material, section for the secondary screening provided with the receiving end adjacent to the discharging end of the section for the primary screening and mounted for permitting secondary screening and discharging the remainder unscreened material through the opposite discharging end, and control means for control of the angle of screening one of the section with respect to the other section of the screen concave. The auxiliary frame is mounted on the main frame for permitting adjustment of the common angle of screening of the screen concave that is controlled by adjusting auxiliary frame with respect to the main frame. The adjustment of the auxiliary frame is limited by the screening angle of the section for secondary screening. The screening angle of one of the screening sections can be adjusted with respect to the other screening section as well as with respect to the common screening angle of the screen concave.

EFFECT: improved quality of separating.

9 cl, 2 dwg

Description

The present device relates to a screening device designed to separate material of a given size fraction from the bulk material supplied to the screening device.

The material intended for sifting can be of any kind, including material for clearing a plot of land for arable land and crushed stone, moreover, this device has dimensions of a sieve hole that allow a material having a smaller size than the size of the sieve holes to pass through these holes, leaving at the same time in the device, residual material having a larger size than the dimensions of the openings of the sieve, which is unloaded separately. Depending on the requirements, the required material, separated from the feed bulk material, may contain material that has passed through the sieve openings and / or may contain material having a larger size than the dimensions of the sieve openings, which are unloaded separately.

It is known that when sifting gravel or material for clearing a plot of land under arable land (including the upper arable layer of soil), so-called "screening decks" are provided, which have, as a rule, a flat screening surface that is slightly inclined to the horizontal plane so that loose material could be loaded onto the deck at the upper loading end or near the upper loading end, for example, by unloading from a lift or a single-bucket loader and then moving along the screening surface along detecting the discharge end, undergoing at the same time sieving, in which the material having a size smaller than the dimensions of the screen openings is separated and is discharged downwardly through the deck, being taken by the discharging device, such as a chute or discharge conveyor.

The screening deck can be functionally connected to a vibrator, which applies vibrational energy to the deck in order to activate screening, and if the deck is tilted relative to the horizontal plane, the action of gravity helps the movement of bulk material along the screening surface. However, in some applications, the deck can be positioned substantially horizontally, so that the forward movement of the bulk material is determined mainly by the way the vibration energy is transferred to the deck.

Obviously, the actual length of time that any particular fraction of the bulk material to be sieved on the screening deck will depend on (a) the properties of the material, (b) the tilt of the deck, and (c) the vibration energy transmitted to the deck. However, the desired length of stay will be a compromise between achieving (1) a higher sieving performance of bulk material and (2) separation efficiency. Thus, a deck that has a larger angle of inclination to a horizontal surface can provide higher sieving performance, but with a drawback of lower separation efficiency in that potentially sifting material can be transferred to the discharge end together with non-sifting material ( there is together with a material the size of which is larger than the size of the sieve holes for sifting).

For this reason, adjustable prior art screening decks (and so-called screening chambers) have been used in the prior art, in which the angle of inclination of the screening surface to a horizontal plane can be adjusted in accordance with the properties of the material intended for screening, for example, dry small aggregates of material effectively separate at a greater angle of inclination of the deck to the horizontal plane than is necessary for the separation of moist soil, which will require more separation for separation Duration of stay on the crash deck.

After passing through the openings of the sieve, the separated material can be conveyed to a dump via an unloading conveyor. In an alternative embodiment, if it is desired to obtain an additional dimensional fraction of the material to be separated, then the separated material may fall onto an additional screen deck having different sizes of sieve openings.

Unseparated material that is discharged from the screen deck can be fed to any appropriate discharge point or, if required, can be sent to an additional screening device.

For this reason, at present, the screening deck, which provides a specific screening function, can unload one part of the sifted material down through the sieve openings for separation by gravity for further processing, for example, unload to a blade, or for processing with an additional separate sieving device on another level; and can unload the second part of the non-sifted material from the discharge end of the deck for separate additional processing, for example, unload to the blade, or for processing with an additional and separate sieving device, which also provides separation at a different level of sieving.

For this reason, the existing designs of sieving plants, as a rule, have several screen decks located at different levels in order to separate the material into different size fractions on sieves, and it is obvious that the yield of various separated dimensional fractions of the material will depend, in particular, from the screening area of each deck. If a large separation capacity of a particular size fraction is required, then a long deck is used, while a shorter deck may be sufficient for lower screen separations. Regardless of the length of the deck, at present all decks are configured to adjust, when necessary, the tilt of the deck relative to the horizontal plane, designed to change the length of time that a particular material being sieved on the deck is sifted.

In the case of using a long deck, this can have a negative effect on the separation efficiency, since since the entire screening surface of the deck is inclined by one angle, the speed of movement of bulk material along the screening surface can vary along the length of the deck, causing a subsequent change in separation efficiency. Thus, at the upper loading end of the deck, the layer of deposited material will usually be much thicker than the material when it moves along the deck to the discharge end, with a subsequent change in productivity and separation efficiency. For this reason, when using a long deck, adjusting the angle of inclination of the screen deck to the horizontal plane must necessarily be a compromise between the desired sifting angle at the upper end of the deck (to ensure the specific required length of time the material stays at the upper end) and the desired sifting angle in other areas of the deck.

The present invention provides a two-section device for the screen deck, which, compared with the known constructions of the screen deck, has a higher ability to respond to the adjustment of the angle of inclination of the deck to the horizontal plane.

In accordance with the present invention, there is provided a screening device for screening bulk material having a screening deck with a loading end for receiving the supplied bulk material, and with an opposite discharge end for unloading residual bulk material after passing through the screening deck, and a frame on which mounted screen deck, in which the screen deck contains

a primary screening section having a loading end for receiving the supplied bulk material and for performing preliminary screening and unloading of the remaining unseparated bulk material through the opposite discharge end;

a secondary screening section having a receiving end adjacent to the discharge end of the primary screening section and arranged to perform secondary screening and discharge the residual unseparated bulk material through the opposite discharge end;

adjusting means providing the ability to adjust the screening angle of one of the sections relative to the other section.

For this reason, in accordance with the present invention, a screening deck is provided having at least two sections with independently adjusting the sifting angle of one section relative to the other so as to enable optimal selection of sieving angles for each section.

Preferably, the sections for primary and secondary screening are mounted on a common auxiliary frame, which itself is mounted with the possibility of adjustment on the main frame. For this reason, when adjusting the auxiliary frame, you can set the overall screening angle for the screen deck, and then, if necessary, you can separately adjust the screening angle of the specified one section so that for any specific separation requirements of the section for primary and secondary screening, you can have separate screening angles set to ensure optimum separation efficiency.

If a longer screen deck is required, then more than two sections (primary and secondary sections) can be provided, and with independent adjustment of the screening angle of at least one of the sections relative to the other section (other sections).

In a preferred embodiment of the device, adjusting the auxiliary frame will limit the sifting angle of the section for secondary sifting, and an independent adjusting means will allow you to set the desired sifting angle of the section for primary sieving.

A screening device according to the present invention can be integrated in a stationary screening unit. In an alternative embodiment, it may be integrated in a mobile screening unit, preferably self-propelled.

Depending on the required number of separated size fractions, additional screening devices, for example additional screening decks, will be provided, and preferably separate discharge conveyors will be provided for unloading the separated bulk material of different size fractions into separate dumps. The unloading conveyors are preferably folded so that they can take any appropriate transport position and can be deployed into unloading positions extending outward during operation. Discharge conveyors may include end conveyors and one or more parallel conveyors.

If a long multi-tiered screen is required, then in a preferred embodiment of the present invention chamber sections for primary and secondary screening are provided, which are otherwise similar to the sections for primary and secondary screening referred to above.

The following is a detailed description of an example of a preferred embodiment of a screening device according to the present invention, made with reference to the accompanying drawings, where

figure 1 is a side view of a two-section screening deck, which is part of a sieving device according to the present invention, and occupying one position relative to the adjustment of the screening angle;

figure 2 is a view similar to the view shown in figure 1, illustrating the additional position of the relative adjustment of the sieving angle of the two sections.

The drawings illustrate a two-section screening deck included in a screening device of the present invention, designed to separate into one or more predetermined size fractions of the bulk material fed to the screening device. However, if a longer screen deck is required, an additional section (or additional sections) can be provided.

Bulk material can be fed to the screening deck using any known means, including elevators and bucket loaders. Similarly, the unloading of one or more separated dimensional fractions can be carried out using one or more discharge conveyors, which can be folded between the transportation positions and deployed in the outward-facing discharge positions and can take the form of parallel conveyors and end conveyors. All these components are not shown in the drawings, but will be quite obvious to ordinary specialists in this field of technology, they are well known and will not be described in more detail in this application.

A screening device according to the present invention may, in addition to a two-section screening deck, which will now be described with reference to FIG. 1 and FIG. 2, comprise screening components.

The screen deck is indicated by a common reference number 10 and has a loading end 11 for receiving the supplied bulk material and an opposite discharge end 12 for unloading the residual bulk material after passing through the screening surface of the screen deck. The screening device has a main frame (not shown) that can be part of a stationary screening unit or can be integrated into the chassis of a mobile screening unit, preferably a self-propelled unit. The sieving device also contains an auxiliary frame, schematically illustrated and indicated by reference number 13, on which the screen 10 of the screen is mounted.

The screen 10 comprises a primary screening section 14 having a loading end 11 that receives the fed bulk material and a screening surface, indicated by a dashed line 15, on which preliminary screening of the fed bulk material is carried out, after which the residual unseparated material is unloaded through the opposite discharge end 16 sections 14 for primary screening. The primary screening section 14 may comprise one screen deck section 15 or may be a multi-deck device or a screening device, having an additional screening surface 15 a located above the screening surface 15.

The secondary screening section 17 has a receiving end 18 located adjacent to the discharge end 16 of the primary screening section 14 and a screening surface 19 (and preferably overlapping the additional screening surface 19a if a multi-deck section device is required to provide a camera for secondary screening), which performs the secondary sifting the residual material received from the primary section 14, and then discharging the residual non-sifted material through the opposite discharge cell ec 20.

The primary screening section 14 and the secondary screening section 17 are mounted on the auxiliary frame 13, wherein the auxiliary frame can be adjusted relative to the main frame in order to establish a common screening angle for the screening deck formed by combining sections 14 and 17 for primary screening and for secondary sifting, respectively, in one node. In the illustrated embodiment, this actually limits the sifting angle for the secondary sifting section 17, and adjusting means (not shown in detail) are provided to enable the sieving angle of the primary sifting section 14 to be adjusted relative to the secondary sifting section 17. Figure 1 shows the essentially coplanar adjustment of the sections for primary screening and secondary screening, while figure 2 shows the adjustment of the section 14 for primary screening by tilting the section up, giving a larger screening angle and therefore a greater effect of the gravity of the bulk material sifting it. The smaller screening angle of the secondary screening section 17 shown in FIG. 2 will provide a longer residence time of the residual bulk material received from the primary screening section 14 in the secondary screening section while it is being secondary screened.

It should be obvious that the illustrated embodiment, which provides independent adjustment of the screening angle of the primary screening section 14, is provided by way of example only and that the present invention provides for independent adjustment of the secondary screening section 17, although not shown.

The present invention also further provides for independent adjustment of the sieving angle of both sections 14 and 17 for primary sieving and secondary sieving, respectively.

To implement the required adjustment of the screening angles of the respective sections of the screen deck, any suitable adjusting mechanism with a manual or power drive may be provided.

As indicated above, an effective one long screen deck can be provided with two separate sections 14 and 17 for primary screening and secondary screening, respectively, but as shown, the present invention also contemplates providing an effective single long screening chamber by providing chamber sections for primary screening and secondary screening, wherein at least one section has a screening angle that can be adjusted relative to the screening angle of the other section.

To activate screening, one, and preferably sections 14, 17 for primary screening and secondary screening, respectively, comprise vibrators 21 for applying vibration energy to the screen decks.

Claims (9)

1. A screening device for screening bulk material, comprising a main frame, an auxiliary frame mounted on the main frame, a screen deck mounted on an auxiliary frame with the ability to set a common screening angle for the screening deck, which comprises a section for primary screening installed with the possibility of primary sifting and having a loading end for receiving the supplied bulk material and an opposite unloading end for unloading residual non-sifted mother la, a section for secondary screening, having a receiving end adjacent to the discharge end of the section for primary screening, and installed with the possibility of secondary screening and unloading of residual non-sifted material through the opposite discharge end, an adjustment tool that allows you to adjust the screening angle of one of the sections relative to the other deck section screen, characterized in that the auxiliary frame is mounted on the main frame with the ability to adjust the overall screening angle screen, set by adjusting the auxiliary frame relative to the base, wherein the auxiliary frame is limited adjustment angle for the secondary screening section of the screening, and screening angle of one of the screening sections can be adjusted relative to the other sections of sieving and screening angle relative to the total of the screening deck. 2. A screening device according to claim 1, characterized in that it comprises a screening deck having more than two sections, at least one of the sections being configured to independently adjust the screening angle relative to the other section. 3. A screening device according to claim 1, characterized in that it is provided with an independent adjusting means for at least setting the desired screening angle of the section for primary screening. 4. A screening device according to claim 1, characterized in that it is integrated in a stationary screening unit. 5. A screening device according to claim 1, characterized in that it is integrated in a mobile screening unit. 6. Screening device according to claim 5, characterized in that the mobile screening device is self-propelled. 7. A screening unit containing a plurality of screening devices according to claim 1 and separate discharge conveyors located for unloading in separate dumps of granular material, divided into different size fractions. 8. A sieving installation according to claim 7, characterized in that the unloading conveyors are arranged to be folded into the appropriate transport position and deployed during operation to the unloading positions extending outward. 9. Screening unit, characterized in that it contains more than one screening device according to claim 1, wherein each of the sections for primary screening and for secondary screening contains a multilevel screen.

Images