WO2012028596A1

WO2012028596A1 - Method and device for filtering out fibers from an air flow

Info

Publication number: WO2012028596A1
Application number: PCT/EP2011/064863
Authority: WO
Inventors: Peter Blankenhorn; Wolfgang Lehner; Nora Stopp
Original assignee: Maschinenfabrik Rieter Ag
Priority date: 2010-08-31
Filing date: 2011-08-30
Publication date: 2012-03-08
Also published as: DE102010035956A1

Abstract

The invention relates to a method and a device for filtering out fibers from an air flow (A) that is suctioned from a textile machine. The air flow (A) is conducted through a filter (4) that lies in a filter chamber, and a scraper (9) is moved along the surface of the filter (4) in order to clean the filter (4), said scraper scraping the fibers that can be found on the filter (4) and transporting said fibers from the filter chamber (3) into a collecting chamber (18) that is emptied from time to time. At least one movable closing means (22) for closing the opening (19) between the filter chamber (3) and the collecting chamber (18) is provided, said closing means closing the connection of the collecting chamber to the filter chamber while the collecting chamber (18) is emptied.

Description

Method and device for filtering fibers from an air stream

The invention relates to a method and an apparatus for filtering fibers from a stream of air extracted from a textile machine processing a staple fiber. In the method, the air flow is passed through a filter disposed in a filter chamber and for cleaning the filter, a scraper is moved along the surface of the filter, which strips off the fibers on the filter and transported into a collecting chamber connected to the filter chamber, the time is emptied at the time. The apparatus includes a filter disposed in a filter chamber, an emptying collection chamber, an opening leading from the filter chamber into the collection chamber, a stripper movable along the surface of the filter for cleaning the filter, and conveying the stripped fibers through the opening into the collection chamber.

Processes and devices of this type are used on textile fibers processing textile fibers. It is often necessary to extract air at various workstations of these textile machines. Together with the air fibers are sucked, which are then carried in the extracted air stream. The fibers are filtered out of the air stream and can then be returned to the processing process. To filter out the air stream carrying the fibers is passed through a filter which retains the fiber material. The fiber material settles on the filter and thereby reduces the suction power of the extraction system, which reduces the upcoming at the workstations of the textile machine vacuum. In many applications, it is necessary that at the workstation of the textile machine as constant a vacuum as possible, since a fluctuating negative pressure can influence the processing process. As constant a vacuum as possible is required, in particular, when the textile machine is a rotor spinning machine or a ring spinning machine with a pneumatic compact spinning device. If, for example, fibers are filtered out of an air stream coming from a pneumatic compact spinning device, a changing negative pressure in the pneumatic compact spinning device at the workstation of the ring spinning machine would lead to a different compacting of the finished warped staple fiber structure and to a different hairiness of the spun yarn. This can adversely affect the subsequent processing stages. In order to avoid clogging of the filter and a decrease in the negative pressure, it is necessary to clean the filter from time to time and to free it from the fiber material deposited thereon.

From DE 197 13 747 A1 a method and a device of the type mentioned is known. There, a scraper movable along the surface of the filter is provided to scrape off the fibers deposited on the surface of the filter and to convey them into a collection chamber. With each stripping of the scraper more fibers are transported into the collection chamber, which thereby continues to fill. From time to time it is now necessary to empty the collection chamber. The device has for this purpose a door which is opened to empty the collection chamber, so that the fiber material can be removed from the collection chamber.

In the device of DE 197 13 747 A1 when opening the door to a pressure drop in the filter chamber and thus in the vacuum system of the textile machine. During the period in which the door is opened, the work stations of the textile machine are supplied with a lower negative pressure, so that, for example, the yarn produced can have different properties.

The invention is based on the object to improve a method and an apparatus of the type mentioned and impairments in the To avoid processing process at the workstations of the textile machine during emptying of the collection chamber.

The object is achieved in the method of the type mentioned in that when emptying the collection chamber their connection to the filter chamber is closed. In the device of the type mentioned, the object is achieved in that the device contains at least one movable closure means for closing the opening between the filter chamber and collection chamber.

By the movable closure means, the collection chamber can be closed during their emptying, so that the collection chamber is no longer connected to the filter chamber under negative pressure. The collection chamber can be emptied without the negative pressure in the filter chamber drops. Thus, the negative pressure at the work stations of the textile machine is not affected by the emptying process of the collection chamber. The scraper is stopped in the emptying of the collection chamber in a certain position, so that no cleaning process of the filter takes place during the emptying process. At the same time, the device according to the invention does not require more installation space than the device known from DE 197 13 747 A1. The device according to the invention is thus very compact and requires only little space.

From DE 199 08 378 A1 a non-generic filter device for a textile machine is known, which contains two separate filter chambers with two separate filters, namely a main filter chamber and a reserve filter chamber. There are louvers and shut-off valves are provided which guide the air flow alternately through the main filter chamber or through the reserve filter chamber. During regular operation, the fibers are filtered out of the suction air stream in the area of the main filter chamber. When the filter in the main filter chamber needs to be cleaned, the suction air flow is directed through the reserve filter chamber. The main filter chamber can then be opened without this exerting an influence on the existing in the reserve filter chamber vacuum. After completion of the cleaning of the main filter chamber the louvers are switched again so that the air flow flows through the main filter chamber again.

The filter device according to DE 199 08 378 A1 requires a very large installation space, which is often not available in the immediate vicinity of the textile machine, and a complex flap system with a complicated actuating mechanism. There are two filter chambers required, with the reserve filter chamber must not fall below a certain minimum size, since here, the entire air flow must be passed through. Finally, the textile machine continues to run during the cleaning of the filter chamber with unchanged performance. Due to the large installation space, the device of DE 199 08 378 A1, in particular for filtering out fibers from an air stream which is sucked off by a pneumatic compact spinning device, is unsuitable if the pneumatic compact spinning device is to be retrofitted to an existing ring spinning machine. On existing ring spinning machines, the space is limited, so that a very small filter device is required for the extracted from the compact spinning device air flow. For this purpose, the filter device according to the invention is particularly well suited due to their small size.

The collection chamber may include a closable emptying port for removing the collected fibers from the collection chamber. Coming from the textile machine, in particular from the spinning machine, the air flow can be passed through a filter chamber containing the filter, wherein the filter chamber may have an opening into the collection chamber opening before the emptying of the collection chamber, in particular before the emptying opening of the collection chamber will, is closed. The at least one movable closure means for closing the opening between the filter chamber and the collection chamber can be formed by one or more movable closure means. In particular contains a closure means a movable closure body or a movable part of a closure body.

In an advantageous embodiment of the invention, a closure means may be arranged in the region of the opening between the filter chamber and the collection chamber. The opening can thus be closed before the emptying of the collecting chamber. Preferably, a flap can be arranged as a movable closure means at the opening. The opening is closed at least during the emptying of the collection chamber. A flap is a simple closure means, which can also relatively easily seal the opening between the filter chamber and collection chamber without much effort. When emptying the collection chamber can be very effectively prevented a pressure drop in the filter chamber. It is advantageous if the flap is automatically opened by the scraper in conveying the stripped fibers into the collection chamber. It can be provided that the flap then automatically closes again. For this purpose, the scraper can have a flap actuator for opening and / or closing the flap.

In a further embodiment of the invention, it may be advantageous if the scraper is adapted to the opening between the filter chamber and collecting chamber. The scraper can be adapted in shape and size to the opening. Alternatively or additionally, the scraper may have at least one closure means adapted to the opening. The closure means may contain, for example, sealing means, in particular in the form of seals. Before the collection chamber is emptied, the scraper can be moved into a position in which the opening is closed by the scraper and / or the closure means arranged thereon.

If the scraper is adapted to the opening, it may be sufficient if the opening is closed except for small gaps around the scraper. A hundred percent sealing of the opening is not required. However, when the wiper is at least one closure means, in particular special, at least one rubber-elastic seal, to ensure a good seal of the opening.

It is advantageous if the scraper is coupled to a scraper drive. The scraper drive can run time-interval-controlled so that the scraper wipes off the fiber material accumulated on the filter at certain intervals and cleans the filter. Preferably, a control device is provided, which is connected to the scraper drive. The control device can be connected to a vacuum sensor, which measures the vacuum present in the filter chamber. If a desired minimum negative pressure is no longer reached, this is an indication that the filter is added. The controller then actuates the wiper drive and the wiper cleans the filter. In addition, the control device can be connected to a switch and a signaling device. If the collecting chamber to be emptied by a machine operator, this actuates the switch and the control device moves the scraper in a defined position, so that the connection of the collecting chamber is closed to the filter chamber. Only then does the control device via the signal device, such as a green lamp, the operator the signal that he can start with the emptying of the collection chamber, without the risk that the negative pressure in the filter chamber or at the workstations of the textile machine by the Opening the emptying opening at the collecting chamber drops.

Further advantages and features of the invention will become apparent from the following description of some embodiments in conjunction with the figures. In a schematic representation:

1 shows a partially sectioned side view of a filter device according to the invention with a scraper, which closes an opening between the filter chamber and the collection chamber, FIG. 2 shows a view of the filter device cut along the sectional surface II-II of FIG. 1,

FIG. 3 shows a variant of a filter device similar to FIG. 1 with a flap arranged at the opening between the filter chamber and the collection chamber in the opened state,

Figure 4 is a partial view of the filter device of Figure 3 with the flap closed.

In Figures 1 and 2, a filter device 1 is shown, which forms a device for filtering fibers from an air stream A. The air stream A is sucked off by workstations, not shown, of a staple fiber-processing textile machine and fed via a channel 2 to the filter device 1. The air stream A can be sucked off, for example, from a rotor housing of a rotor spinning machine or from a vacuum channel of a pneumatic compact spinning device on a ring spinning machine. In both cases, fibers are sucked in from the processed staple fiber material by the air flow and transported along with the air flow A. The air flow A is passed through the filter device 1 in order to filter out the fibers again from the air stream and feed them back to the yarn production.

The filter device includes a filter chamber 3, a filter 4 and a fan 5. The filter 4 consists of a fine sieve or grid and is shown schematically as a dashed line. The fan 5 is driven by a drive, not shown, and generates the necessary negative pressure in the filter chamber 3, to suck the air flow A from the jobs of the textile machine. As an alternative to the fan 5, it would also be possible to provide a connection to a central vacuum source of the spinning mill. The filter 4 is seated on a wall 6 delimiting the filter chamber 3. The wall 6 has a cutout 7, which is covered by the filter 4. Behind The wall 6, a funnel 8 is arranged, which directs the air flow B, from which the fibers have been filtered out, to the fan 5. The exhaust air from the fan 5 is derived in a manner not shown.

The filter 4 settles over time by the filtered out of the air stream A fiber material and must be cleaned. For this purpose, a scraper 9 is provided, which is movable along the surface of the filter 4. The scraper 9 consists essentially of a pivot arm 10 which is pivotally mounted on an axis 1 1 and coupled to a scraper drive 12. The pivot arm 10 is provided with a wiper lip 13 which rests on the surface of the filter 4. The scraper 9 can be pivoted by the scraper drive 12 about the axis 1 1 in the direction of the double arrow C, see Figure 2, back and forth. In Figures 1 and 2, the scraper 9 is shown in its lower end position. In Figure 2, the upper end position of the scraper 9 is indicated by dash-dotted lines. The dot-dashed position of the scraper 9 is its rest position.

The filter device 1 includes a control device 14, which is connected via a dashed lines indicated electrical connection 15 with the scraper drive 12. In the filter chamber 3, a vacuum sensor 16 is arranged, which is connected via the dashed lines indicated electrical connection 17 with the control device 14.

If, during operation, the filter 4 continues to expand with fiber material, the negative pressure in the filter chamber 3 drops below a prescribed minimum value. This is detected by the vacuum sensor 16 and reported to the controller 14. The control device 14 then starts the scraper drive 12. The scraper 9 is moved along the surface of the filter 4 and strips off the fibers located on the filter 4. Below the filter chamber 3, a collection chamber 18 is arranged. The filter chamber 3 is connected via an opening 19 with the collection chamber 18 in connection. Now, the scraper 9 pivots out of its resting position shown in phantom in FIG. Position down and moves to the position shown in Figure 1, the fibers stripped from the filter 4 are transported by the scraper 9 through the opening 19 into the collection chamber 18. The collection chamber 18 has an emptying opening 20 which can be closed by a door 21. The door 21 is shown in Figure 1 as a hinged door, but may also be a sliding door in a non-illustrated embodiment. A machine operator may, after opening the door 21, empty the collection chamber 18 through the emptying opening 20. Would he do this, as long as the scraper 9 is in the rest position shown in phantom in Figure 2, so would be sucked through the opening 19 in the filter chamber 3 when opening the door 21 by the prevailing in the filter chamber 3 negative pressure. As a result, the negative pressure in the filter chamber 3 can drop, so that the suctioned from the textile machine air flow A decreases and the prevailing at the workstations of the textile machine vacuum also decreases. In addition, already collected in the collection chamber 18 fiber material can be sucked back through the opening 19 in the filter chamber 3 and clog the filter 4 again.

In order to avoid this, it is provided according to the invention that, when the collecting chamber 18 is emptied, its connection to the filter chamber 3 is closed. This is achieved by a movable closure means 22 for closing the opening 19. In the variant shown in Figures 1 and 2, the scraper 9 forms with its pivot arm 10, the movable closure means 22. The illustrated in Figures 1 and 2 lower pivot position of the scraper 9 is the position in which the scraper 9, the opening 19 between the filter chamber 3 and collecting chamber 18 closes. In order to achieve a particularly good sealing of the opening 19, the scraper 9 may contain further closure means 22 in the form of sealing means, in particular seals 23 and 24. The sealing means 23, 24 are arranged on the scraper 9 and seal the scraper 9 to boundary walls 25, 26 of the filter chamber 3 from. So that the door 21 is opened at the emptying opening 20 of the collecting chamber 18 only when the scraper 9 is in the position closing the opening 19, the control device 14 is shown by dashed lines electrical connections 27 and 28 with a switch 29 and a signaling device 30th connected. If the collecting chamber 18 to be emptied by a machine operator, the machine operator operates the switch 29. Then, the controller 14 outputs a signal to the scraper drive 12 and moves the scraper 9 in the position shown in Figure 1, in which the opening 19 is closed. When the scraper 9 has reached this position, the control device 14 gives the machine operator via the signal device 30, which may be formed for example by a green lamp, an enable signal. The machine operator can then safely open the door 21 and empty the collection chamber 18. After completion of the emptying he can again operate the switch 29 and signal the controller 14 that the emptying process is completed. The signaling device 30 may include a locking mechanism for the door 21 in a manner not shown, with the opening of the door 21 can be prevented, as long as the scraper 9 is not in the opening 19 occluding position. The locking mechanism is connected to the control device 14 and is controlled by it accordingly.

FIGS. 3 and 4 show a variant of the filter device 1. The same reference numerals denote the same parts, so that a repeated description is omitted to avoid repetition.

In the filter device 1 of Figures 3 and 4, the closure means 22 for the opening 19 between the filter chamber 3 and the collection chamber 18 is not formed by the scraper 9. Here, the movable closure means 22 is formed by a flap 31. The flap 31 is pivotally arranged in the region of the opening 19. The flap 31 is attached via a pivot axis 32 to the boundary wall 25 of the filter chamber 3. The flap 31 is shown in Figure 3 in the open and in Figure 4 in the closed state and can be pivoted in the direction of the arrows D and to.

The scraper 9 has a flap actuator 33 for opening the flap 31. The flap actuator 33 is an operating lever for the flap 31, which is attached to the pivot arm 10 of the scraper 9. On the flap 31, a weight 34 is attached, which always tries to close the flap 31 by its arrangement and its tuned to the mass of the flap 31 mass. As an alternative to the weight 34, a closing spring may be arranged on the flap 31 in an embodiment which is not shown.

In Figure 4, the scraper 9 is in its rest position, see dot-dashed position in Figure 2. In this position, the flap 31 is closed. Now, if the filter 4 must be cleaned, the scraper 9 is pivoted by the scraper drive 12 down. During the pivoting movement, the flap actuator 33 attached to the pivoting arm 10 abuts against the flap 31 and opens it. When the scraper 9 reaches the lower end position shown in FIG. 3, the flap actuator 33 has completely opened the flap 31 and the fiber material stripped off by the scraper 9 can fall into the collecting chamber 18. When swinging back the scraper 9 in its rest position, the flap 31 is automatically closed by the weight 34 again.

If now the collection chamber 18 are emptied by the operator, he actuates the switch 29 and the control device 14 pivots the scraper 9 in the upper position shown in Figure 4, so that the flap 31 is closed. If the scraper 9 is already in the rest position, it remains there during the emptying process. Then, the controller 14 outputs the enable signal via the signal device 30. The machine operator can open the door 21 of the emptying port 20 and empty the collecting chamber 18. The opening 19 between the collection chamber 18 and filter chamber 3 is during the emptying process through the flap 31 closed and sealed. The negative pressure in the filter chamber 3 can not be affected during the emptying process. After completion of the emptying of the collecting chamber 18, the machine operator again actuates the switch 29, so that the scraper 9 can continue with its cleaning work. Alternatively, the closing of the door 21 could be monitored via a sensor connected to the control device 14, so that the control device 14 automatically detects when the door 21 is closed again after emptying the collecting chamber 18.

Designation filter device

channel

filter chamber

filter

fan

wall

neckline

funnel

scraper

swivel arm

axis

stripper drive

wiping lip

control device

electrical connection

Under pressure sensor

electrical connection

plenum

opening

emptying opening

door

closure means

poetry

boundary wall

electrical connection

switch 30 signal device

31 flap

32 pivot axis

33 flap actuator

34 weight

A airflow

B airflow

C pivoting movement

D pivoting movement

Claims

Patent claims

1 . A method of filtering fibers from a stream of air extracted from a textile machine processing a staple fiber (A), wherein the air stream (A) is passed through a filter (4) disposed in a filter chamber (3) and a wiper for cleaning the filter (4) (9) is moved along the surface of the filter (4) which strips the fibers on the filter (4) and carries them into a collection chamber (18) connected to the filter chamber (3), which is emptied from time to time characterized in that when emptying the collection chamber (18) their connection to the filter chamber (3) is closed.

2. The method according to claim 1, characterized in that the filter chamber (3) has an opening into the collecting chamber (18) opening (19), and that this opening (19) before the emptying of the collecting chamber (18) is closed.

3. The method according to claim 2, characterized in that the opening (19) is closed at least during emptying of the collecting chamber (18).

4. The method according to claim 2 or 3, characterized in that the opening (19) from the scraper (9) for conveying the stripped fibers into the collection chamber (18) automatically opened and then closed again.

5. The method according to claim 2 or 3, characterized in that the scraper (9) is adapted to the opening (19) and / or at least one of the opening (19) adapted closure means (22), and that the scraper (9 ) is moved before the emptying begins in a position in which the opening (19) of the scraper (9) and / or the closure means (22) arranged thereon.

6. An apparatus (1) for filtering out fibers from a textile machine that is extracted by a staple fiber, with a filter (4) arranged in a filter chamber (3), an emptying collection chamber (18), one of the filter chamber (3 ) in the collection chamber (18) leading to opening (19), a along the surface of the filter (4) movable scraper (9) for cleaning the filter (4) and for conveying the stripped fibers through the opening (19) into the collecting chamber ( 18), characterized in that the device (1) at least one movable closure means (22) for closing the opening (19) between the filter chamber (3) and collecting chamber (18).

7. Apparatus according to claim 6, characterized in that the

Collecting chamber (18) has a closable emptying opening (20) for removing the collected fibers from the collection chamber (18).

8. Apparatus according to claim 6 or 7, characterized in that the scraper (9) with a scraper drive (12) is coupled, and that the device comprises a control device (14), at least with the scraper drive (12), a switch ( 29) and a signaling device (30) is connected.

9. Device according to one of claims 6 to 8, characterized in that the scraper (9) is adapted to the opening (19) and forms a movable closure means (22).

10. Device according to one of claims 6 to 9, characterized in that the scraper (9) contains at least one closure means (22).

1 1. Device according to one of claims 6 to 8, characterized in that a closure means (22) in the region of the opening (19) is arranged.

12. The device according to claim 1 1, characterized in that as a movable closure means (22) a flap (31) at the opening (19) is arranged.

13. The apparatus according to claim 12, characterized in that the

Scraper (9) has a flap actuator (33) for opening and / or closing the flap (31).