DE202015106653U1 - screening machine - Google Patents

Abstract

Sieving machine for size-dependent separation of bulk materials, comprising - a sieve box (1) which is provided with at least one sieve surface (1c) for sieving bulk material, and - a drive unit (5) by means of which the sieve box (1) is set into oscillation, wherein the sieve box (1) has at least one support section (1b), via which support section (1b) the sieve box (1) is mounted on a base (4) via at least one suspension element (2) utilizing the compressibility of gases, characterized in that the at least one suspension element (2) is provided with at least one check valve (2b) in order to prevent a sudden escape of gas from the suspension element (2).

Description

FIELD OF THE INVENTION

The invention relates to a screening machine for size-dependent separation of bulk materials, comprising a sieve box, which is provided with at least one sieve surface for sieving bulk material, and a drive unit, by means of which the sieve box is set in vibration, wherein the sieve box has at least one support portion, via which Support section of the screen box is mounted on at least one compressibility of gases ausnützendes suspension element to a substrate.

STATE OF THE ART

Cantilevered screening machines, which essentially include the circular vibrating screens, linear vibrating screens, elliptical vibrating screens and conveyor troughs, are usually mounted on a base via spring elements - directly or indirectly.

The most common spring elements are coil springs, rubber springs, hollow rubber springs and Rosta spring elements.

All of these types of suspension generate during operation of the screening machine still relatively high residual forces in the ground (for direct storage) or in a support structure, which is arranged in indirect storage between the spring elements and the ground to keep the screen box at a certain height level. Accordingly, such a support structure must often be designed as a heavy and expensive steel construction.

Such residual forces can initially be significantly reduced only with the help of a correspondingly elaborate Gegenschwingrahmens. However, this means high additional costs which can usually only be accepted in larger plants, such as steel works or mines.

In order to ensure a comparable reduction of said residual forces even without the use of a Gegenschwingrahmens, it may now be provided to replace the aforementioned conventional spring elements by suspension elements, which exploit the compressibility of gases.

However, the use of such suspension elements involves the risk that in the event of a leak in the gas supply to a very rapid escape of gas from the suspension elements can come. As a result, collisions between the moving - because still driven by the engine - screen box and the substrate on which the screening machine is mounted, or said support structure with indirect storage of the screening machine difficult to avoid, thereby reducing the risk of damage to the screening machine or The infrastructure surrounding the screening machine is very high.

OBJECT OF THE INVENTION

It is therefore an object of the present invention to provide a screening machine described above, in which the risk of damage in the event of a leak in the gas supply line of the suspension elements is minimized.

PRESENTATION OF THE INVENTION

In a screening machine according to the invention for the size-dependent separation of bulk materials, comprising a screen box, which is provided with at least one screen surface for screening bulk material, and a drive unit, by means of which the screen box is vibrated, wherein the screen box has at least one support portion, on which support portion the screen box is mounted on at least one of the compressibility of gases ausnützendes suspension element to a substrate, the object underlying the invention is achieved in that the at least one suspension element is provided with at least one check valve to prevent a sudden escape of gas from the suspension element.

By the use according to the invention such non-return valves - in principle check valves and non-return valves are included - it is possible, the risk of damage in the event of a leak in an air supply line (or another compressible gas leading line, which is connected to the at least one suspension element) on a Minimize minimum, since in such a case, the outflow of gas from the suspension element is automatically prevented and the functionality of the suspension element is maintained at least over a period of time within which the screening machine can be controlled brought to a standstill.

Namely, in check valves, a closing member is closed in one direction (closing direction) by the flowing fluid, while in the other direction (releasing direction), it is released from the flowing fluid. In the case of spring-loaded non-return valves, the pressure prevailing in the release direction must exceed the restoring force of a spring urging the closing element in the closed position, so that it can flow through in the release direction.

Therefore, even in a case in which the air supply only recorded a small pressure drop - by a suitable choice of the spring force of the check valve - a pressure drop in the suspension element can be prevented.

Suspension elements which are particularly suitable for use in sieving machines according to the invention are air spring bellows. Therefore, it is provided in a particularly preferred embodiment of the screening machine according to the invention, that the suspension element is formed by at least one air spring bellows.

According to the invention, it can be provided that the suspension element comprises a plurality of air spring bellows in order to distribute the total weight of the screen box evenly.

In order to avoid the need for manual filling of the bellows with air, it is provided in a further preferred embodiment of the screening machine according to the invention that the at least one air spring bellows is connected to an air supply line. In the case of several bellows forming the suspension element, either each individual air spring bellows can be connected to a separate air supply line, or a group of air spring bellows, for example the air spring bellows arranged on one side of the screen box, can be connected to a common air supply line.

An integration of the air spring bellows in a control loop for - if necessary automatically carried out - adjustment of the pressure values of the individual air spring bellows can be done by means of these air supply lines.

In a further preferred embodiment of the screening machine according to the invention, it is provided that the at least one air spring bellows a check valve forming, air inlet side provided, preferably spring-loaded, check valve to fall below a predetermined Einströmdruckes the air in the air bag, a leakage of air from the air bag in to automatically stop the air supply.

This is a particularly simple and inexpensive embodiment of the screening machine according to the invention. Both the air spring bellows forming the suspension element and the non-return valves forming the non-return valves are standard parts which can easily be exchanged even in the event of wear.

In practice, it may be of great advantage - for example, in the case of continuous production lines - to keep the screen box independent of its current loading state at a constant height level (distance between base and screen box).

It is therefore provided in a further particularly preferred embodiment of the screening machine according to the invention that the at least one suspension element at least one control block, for filling and bleeding the air spring bellows, at least one pressure sensor, which is associated with a respective air spring bellows to measure the pressure prevailing in the air bag and forward to the control block, at least one distance sensor which measures the distance between the ground and sieve box and forwards to the control block, and at least one control unit, in which all information converge, are processed, and which controls the filling or venting of the bellows, comprising to keep the screening machine in a specific position and orientation independently of a load condition of the screen box.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be explained in more detail with reference to an embodiment. The drawings are exemplary and are intended to illustrate the inventive idea, but in no way restrict it or even reproduce it. Showing:

1 a schematic side view of a screening machine according to the invention

2 a front view of the screening machine 1

3 a schematic view of a control loop, as it comes in a screening machine according to the invention is used

WAYS FOR CARRYING OUT THE INVENTION

1 shows a schematic view of a screening machine according to the invention. There is a sieve box 1 the screening machine via support sections 1b by means of several suspension elements 2 on a surface 4 stored. A drive unit 5 is with the sieve box 1 connected (see 2 ), for a periodic shaking movement of the sieve box 1 to care.

In the concrete embodiment, the suspension elements 2 each through several bellows 2a educated. These bellows 2a are designed as consoles and with the sieve box 1 connected support sections 1b elastic with a sieve support structure 3 connected, which sieve support construction 3 turn on the ground 4 is stored.

This sieve support structure 3 is executed in the concrete embodiment as part of the screening machine. However, embodiments of the screening machine are included in the concept of the invention, in which the Siebunterstützungskonstruktion 3 integral with the substrate 4 formed, or the Siebunterstützungskonstruktion 3 not available at all and the screening machine by means of the suspension elements 2 directly on the ground 4 is stored.

Furthermore goes out 1 the position of a sieve surface 1c of the sieve box 1 out. However, this screen is flat 1c only indicated by dashed lines, as they are from a side panel 1a of the sieve box 1 is covered. The sieve surface 1c usually has several interconnected Siebbeläge, by means of which a size-dependent separation of bulk materials takes place.

2 shows the screening machine 1 , but in a front view. In synopsis with 1 shows that the screening machine in the concrete embodiment, a total of four by four air spring bellows 2a trained suspension elements 2 wherein each of the total of four support sections 1b by means of a respective suspension element 2 with the sieve support structure 3 connected is.

3 shows the schematic structure of a control loop for automatically filling and bleeding the suspension elements 2 a screening machine according to the invention. There are a total of four suspension elements 2 by means of two air supply lines 2c with a control block 6 connected. The control block 6 typically includes means for receiving and discharging air from an air supply unit 8th over the air supply lines 2c to the suspension elements 2 ,

In the concrete embodiment, the control block 6 integral with a control unit 7 educated. This controller 7 collects measurement information on the one hand from pressure sensors that are within the suspension elements 2 measure prevailing pressure, as well as distance sensors, the distance between the sieve box 1 or the support sections 1b and the underground 4 or the Siebunterstützungskonstruktion 3 measure, and controls depending on these parameters, the filling or venting of the individual suspension elements 2 ,

Each of the four suspension elements 2 has two bellows 2a on, which in each case via a non-return valve designed as a check valve 2 B with the air supply 2c are connected. Here are the existing bellows 2a grouped into two groups, each group having its own air supply 2c associated with all the bellows 2a connected to this group.

FUNCTIONING OF THE INVENTION

Referring to 3 the mode of operation of the invention is explained below:
In normal operation of the screening machine according to the invention, as in 1 and 2 shown, prevent the bellows 2a the direct transfer of currently in and on the screen box 1 acting forces on the screen support structure 3 or on the ground 4 on which the screening machine is supported.

The filling and venting of the individual bellows 2a happens by means of a control unit, comprising at least the control block 6 as well as the control unit 7 , About the air supply lines 2c gets air from the air supply unit 8th to the four air suspensions 2 directed.

The bellows 2a are each on an air inlet side on the air bag 2a arranged check valve 2 B , in the case of several bellows 2a preferably over at each air bag 2a arranged check valves 2 B , with the air supply 2c connected. As a result, a filling of the respective air spring bellows 2a over the check valve 2 B At any time, however, venting is done via an additional valve, not shown, for example, via an electrically controllable check valve for each air bag separately.

In case of a leak in one of the two air supply lines 2c is a sudden escape of air from the bellows 2a in the air supply line 2c due to the check valves 2 B not possible, reducing the functionality of the suspension elements 2 is still sufficiently long after the occurrence of such a leak is guaranteed to bring the screening machine controlled to a halt.

Due to the pressure drop within the air supply line 2c becomes a (not provided with reference numeral) closing element of the check valve 2 B automatically moved to its locked position. This can, for example, in the case of spring-loaded check valves by spring force, and / or by the inside of the bellows 2a prevailing pressure to happen. Also possible would be an electrical control of the closing element, for example by the control unit 7 ,

Similarly, it can be provided that the distance sensor, preferably continuously, the current position and orientation of the screen box 1 determined and these measurement data to the control unit 7 forwards. This measurement can be done in a simple manner by the distance between one, usually the lowest point of the sieve box 1 containing, area of the sieve box 1 and the underground 4 is measured. However, more complicated measuring methods are possible in which the distance to the ground 4 not at one but in several places of the sieve box 1 In order to draw conclusions not only on the current position but also on the current orientation of the screen box 1 relative to the ground 4 to allow.

Depending on these measurement data, the controller may 7 by individual filling or venting of individual bellows 2a the correction of the current position and orientation of the sieve box 1 cause.

LIST OF REFERENCE NUMBERS

1

screenbox

1a

side panel

1b

bearing section

1c

Screen area

2

The suspension pad

2a

suspension bellows

2 B

Check valve (check valve)

2c

air supply

3

Siebunterstützungskonstruktion

4

underground

5

drive unit

6

control block

7

control unit

8th

Air supply unit

Claims (5)

Sieving machine for size-dependent separation of bulk goods, comprising - a sieve box ( 1 ), which with at least one screen surface ( 1c ) is provided for screening of bulk material, and - a drive unit ( 5 ), by means of which the sieve box ( 1 ) is vibratable, wherein the sieve box ( 1 ) at least one support section ( 1b ), over which support section ( 1b ) the sieve box ( 1 ) via at least one compression element of the gases exploiting suspension element ( 2 ) on a substrate ( 4 ), characterized in that the at least one suspension element ( 2 ) with at least one check valve ( 2 B ) is provided to prevent a sudden escape of gas from the suspension element ( 2 ) to prevent. Screening machine according to claim 1, characterized in that the suspension element ( 2 ) by at least one air spring bellows ( 2a ) is trained. Screening machine according to claim 2, characterized in that the at least one air spring bellows ( 2a ) with an air supply line ( 2c ) connected is. Sieving machine according to claim 3, characterized in that the at least one air spring bellows ( 2a ) the non-return valve ( 2 B ) forming, air inlet side provided, preferably spring-loaded, check valve ( 2 B ), in order to fall below a predetermined Einströmdruckes the air in the air bag ( 2a ) leakage of air from the air bag ( 2a ) in the air supply line ( 2c ) automatically stop. Screening machine according to one of the preceding claims, characterized in that the at least one suspension element ( 2 ) - at least one control block ( 6 ), for filling and bleeding the bellows ( 2a ), - at least one pressure sensor, which in each case a Luftfederbalg ( 2a ) is assigned to the in the air bag ( 2a ) to measure prevailing pressure and forward it to the control block, - at least one distance sensor, which determines the distance between background ( 4 ) and sieve box ( 1 ) and forwards to the control block, and - at least one control unit ( 7 ), in which all the information converges, is processed, and which controls the filling or venting of the bellows, in order to keep the screening machine independent of a loading state of the screen box ( 1 ) in a specific position and orientation.

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