CN109423714B

CN109423714B - Device for adjusting fiber cotton flow in cleaner

Info

Publication number: CN109423714B
Application number: CN201810961587.0A
Authority: CN
Inventors: T.瓦夫尔; R.安格兰
Original assignee: Maschinenfabrik Rieter AG
Current assignee: Maschinenfabrik Rieter AG
Priority date: 2017-08-30
Filing date: 2018-08-22
Publication date: 2022-06-24
Anticipated expiration: 2038-08-22
Also published as: CH714101A1; EP3450597B1; CN109423714A; EP3450597A1

Abstract

The invention relates to a device and a corresponding method for adjusting a fiber cotton flow (24, 25) in a cleaner (5) in a spinning preparation system. The stream of fiber batting (24, 25) is guided in a transport line (4) to an inlet of the cleaner (5) and leaves the cleaner (5) through an outlet (18) after passing through a cleaning chamber (30), wherein the cleaner has an inlet connection (17) for connecting the transport line (4). A static pressure measuring element (23) is arranged in the flow of cellucotton (24) in the inlet connection (17), or in a transport line (4) upstream of the inlet connection (17), or in the cleaning chamber (30), and an exhaust pipe (19) is arranged upstream of the pressure measuring element (23), which exhaust pipe (19) is connected to the transport line (4) and has an exhaust fan (20) with a drive (21). A target value of the pressure is assigned to a predetermined or prevailing operating state of the cleaner (5). A control of a driver (21) of the exhaust fan (20) is provided for adjusting a pressure target value in the cleaner (5).

Description

Device for adjusting fiber cotton beam flow in cleaner

Technical Field

The invention relates to a method and a device for regulating the flow of a fiber fleece in a cleaner in a spinning preparation system.

Background

Fiber processing machines such as intermediate storage devices, mixers and carding machines are used in spinning preparation systems for cleaning, mixing and separating the fiber material into individual fibers and also for aligning the fibers in parallel. These machines have in common that they have a cotton bale feed. The fibrous material to be processed is fed in the form of a fibre bale through a pneumatic conveyor into the fibre processing machine. Here, the cleaner used in the spinning preparation system is operated in a continuous operation. In doing so, the fiber batt is fed to the inlet of the cleaner in a uniform flow of fiber batt and is transported through the cleaner by the rotating cleaner roller. The fiber fleece stream consisting of the fiber fleece to be cleaned is guided to the cleaning device by means of the necessary conveying air with pneumatic conveying capacity around the fiber fleece. The conveying air is transported through the cleaner together with the fibre fleece. After exiting the cleaner through the outlet, the stream of fibrous batt is transported by means of a fan to the next machine downstream in the spinning preparation system, such as a mixer.

It is known from the prior art that regulators and controls can be provided to ensure the most uniform possible volume flow of the delivery air and thus of the flow of cellucotton. For example, CH 696909 a5 discloses one such regulator. It is also known to provide a second air opening at the beginning of the pneumatic conveying, i.e. in the present case the outlet of the mixer, to ensure the regulation of the downstream fan. However, in order to obtain high quality and uniform cleaning in the cleaner, constant operating conditions must be ensured. The operating conditions in the cleaner are influenced by the pneumatic feeding of the fiber wool pack and the pneumatic discharge and the provision of a second air opening or exhaust opening. The mixture of the fiber flocks to be processed and the conveying air is also not homogeneous, since the fiber flocks may enter in different sizes. Volumetric flow in the cleaner and pressure conditions are also one of the reasons.

One disadvantage of the known prior art is that the result to be achieved by cleaning the fiber wool flock in the cleaning appliance is determined not only by the volume flow of the conveying air and the rotational speed of the cleaning appliance roller, but also by the behavior of the fiber wool flock inside the cleaning appliance. For example, at high volumetric flow rates, the fiber cotton bale is driven through the cleaner by the conveying air and fails to have its desired interaction with the cleaner roller. Due to the elevated pressure in the inlet of the cleaner, the fiber cotton bundle is compressed and thus the cleaning effect is poor.

Disclosure of Invention

The object of the present invention is therefore to achieve a device for adjusting the flow of fibre cotton in a cleaner which will allow a uniform cleaning of the fibre cotton flow in the cleaner, irrespective of the pneumatic feeding and the pneumatic discharge of the fibre cotton flow.

This object is achieved by the features in the characterizing portion of the independent claim.

To achieve this object, a novel device and a corresponding method for adjusting the flow of a fiber fleece in a cleaner in a spinning preparation system are proposed. The stream of fibre wool is led to the inlet of the cleaner through a transport line and leaves the cleaner through an outlet after passing through the cleaning chamber, so that the cleaner has an inlet connection for connecting the transport line. A static pressure measuring element is arranged in the flow of fiber fleece and in the transport line upstream of the inlet connection and the pressure measuring element, and an exhaust pipe is arranged in the inlet connection or in the transport line upstream of the inlet connection and the pressure measuring element, which exhaust pipe is connected to the transport line and has a ventilation fan with a drive. The target value of the pressure is assigned to a predetermined operation state or a current operation state of the cleaner. A controller for a driver of the exhaust fan is provided for adjusting a pressure target value in the cleaner.

Because of the different composition of the flow of cellucotton fibres, the flow of cellucotton fibres has an influence on the operating conditions, in particular the pressure conditions in the cleaner, which can be minimized by using the device.

The static pressure in the flow of cellucotton is measured and regulated by means of an exhaust fan. In doing so, the static pressure measurement may be performed in the inlet connection of the cleaner or in the transport line upstream of the inlet connection. Because the static pressure is measured and the dynamic pressure dependent on the flow is neglected, the pressure measurement can be made at an easily accessible location, irrespective of the flow conditions prevailing at that location inside the transport line or the inlet connection. Alternatively, a pressure measuring element can also be provided in the cleaning chamber of the cleaning appliance. The clean room refers to the area of the cleaner through which the flow of fiber batting is directed between the inlet and the outlet. The measured static pressure is transmitted to the controller as an actual value of the pressure. The controller compares the actual value with a predetermined target value and, in accordance with the defined difference, a control signal is output to a driver of the exhaust fan. The exhaust fan supports separation of the fiber cotton bundles in the inlet area of the cleaner from the transport air, which helps to maintain a desired relationship between the transport air and the amount of fiber cotton bundles contained in the transport air in the cleaner. As seen in the flow direction of the flow of the stream of fibrous batt, the connection of the exhaust pipe to the transport line is provided upstream of the inlet connection into the cleaner and upstream of the pressure measuring member. The connection (tie-in) of the exhaust pipe to the transport line is equipped with a corresponding system for holding the fiber wool pack in the transport line. Here, a grid, a sieve, a filter cloth or other means known from the prior art may be used.

The pressure drop caused by the additional control of the volume flow of the conveying air in the transport system therefore has no influence on the pressure zero point or the volume flow in the cleaning device. The pressure zero is established between the two fans. The pressure zero moves as a function of the operating point of the fans between these fans and the transport path when there is no adjustment of the pressure. In the cleaner, the same condition always prevails due to the pressure adjustment, and any deviation into the pressure zero point of the cleaner is suppressed. It is also possible to compensate for the influence of the filter cover, which is usually incorporated into the exhaust and transport system. Thus, the inefficient open transport installed after each machine in the prior art is eliminated in the cleaner. A controlled pressure differential between the inlet and outlet of the cleaner is ensured.

The static pressure measuring element is advantageously arranged in the inlet connection of the cleaner, which thus produces a stable condition. Suitable pressure measuring elements are known from the prior art, such as spring pressure sensors, piezoresistive or piezoelectric pressure sensors or capacitive and inductive pressure sensors. Since the pressure collector is arranged in the inlet connection of the cleaner, the influence of the transport from the fibre fleece strand in the transport line or in the cleaner is minimized.

It is also advantageous that the prevailing operating conditions can be determined by the controller from the flow of cellucotton. This function can be taken over from measurements of upstream components of the spinning preparation system, such as, for example, the bale breaker or the transport line. It is also conceivable to measure the number of fibre flocks in the conveying air stream or the transport air stream. Based on these parameters, the cleaner is adjusted (rotation speed, grid alignment, etc.) and the desired cleaning of the fiber cotton bundle is obtained at a certain pressure. However, the reverse path is also conceivable, so that the cleaner is manually adjusted to a certain production and thereby an operating state is obtained and used to determine the target value of the pressure.

It is also advantageous that the operating state is predetermined and that the target value of the pressure can thus be set manually on the controller. Thus, empirical values can be entered or operations can be performed at varying pressures without changing other parameters.

It is particularly advantageous to adjust the adjustment so that the static pressure in the cleaner is constant. In so doing, the fluctuation of the set target value is not taken into account, as compared with the adjustment based on the changed operating parameter, and stable operation is made possible. Alternatively, minor fluctuations in the pressure regulation may be prevented by appropriate suppression by the controller or selective consideration of target value changes.

The exhaust fan is preferably connected to the exhaust system of the spinning preparation system. Spinning mills are usually equipped with a central exhaust system which filters the exhaust gas before it is discharged to the outside or fed back into the system.

A method for regulating a flow of a stream of fibrous lint in a cleaner in a spinning preparation system is also proposed, wherein the stream of fibrous lint is transported to an inlet of the cleaner by a transport line and is discharged from the cleaner after passing through a cleaning chamber through an outlet, wherein the cleaner has an inlet connection for connecting the transport line. The static pressure is measured in the flow of the fiber fleece in the inlet connection, or in the transport line upstream of the inlet connection, or in the clean room. An exhaust pipe is arranged in the transport line upstream of the inlet connection and upstream of the pressure measuring element, which exhaust pipe is connected to the transport line and has an exhaust fan with a drive. A target value for pressure in the cleaner is determined from a predetermined or prevailing operating state of the cleaner. The pressure in the cleaner is adjusted at a previously determined target value by controlling the driver of the exhaust fan. The flow of cellucotton is advantageously conveyed through the cleaner inlet at a constant flow rate of conveying air. Maintaining a constant flow rate of the conveying air makes it necessary to measure the flow of conveying air and to regulate the fan in the transport line to the cleaner.

Drawings

The invention is explained in more detail below on the basis of exemplary embodiments and is illustrated by the accompanying drawings, in which:

figure 1 shows a simplified schematic of a spinning preparation system according to the prior art; and

figure 2 shows a schematic view of an embodiment of the present device.

Detailed Description

Fig. 1 shows a simplified schematic of a spinning preparation system. The sequence of machines in the spinning preparation system as described below and illustrated in fig. 1 is given as an example and may also be implemented in other arrangements or with the addition of other machines. The fibres supplied to the spinning mill in the form of fibre bales 1 are broken into fibre cotton bundles using a bale breaker 2. The fiber cotton bundle moved from the fiber bale 1 using the bale breaker 2 is transported as a fiber cotton bundle flow to the cleaner 5 via the transport fan 3 by means of transport air or transport air in the transport line 4. The fiber cotton tow stream passes through a cleaner 5 where the fiber cotton tow is decontaminated. The fibre fleece bunch is supplied from the cleaner 5 to the mixer 8 via a transport line 6 and by means of an additional transport fan 7. The fiber flocks that have been introduced are mixed in the mixer 8 to obtain the most homogeneous distribution possible of the various fiber components. The fibre cotton bundle is taken from the mixer 8 and fed by means of a further transport fan 10 through a transport line 9 into a distributor 11. The fibre tow then proceeds from the distributor 11 to a carding machine 12 where it is broken into individual fibres and the fibres are arranged in parallel, cleaned, supplied in the form of slivers for further processing.

Figure 2 shows a schematic view of an embodiment of the present device. The flow of lint prior to 24 is sent to the inlet connection 17 of the cleaner 5 via the transport line 4. The cleaner 5 comprises a cleaner roller 13 which rotates in a direction 15 and is fitted on its circumference with beater (beater) elements 14. The fiber fleece guided into the inlet connection 17 is first conveyed around the cleaner roller 13 by the entrained conveying air and then by the rotating cleaner roller 13 and/or the beater element 14. In doing so, the fiber cotton bale is conveyed on a grid 16, which removes contaminants from the fiber cotton bale. The flow 24 of fibrous batt entering the cleaner 5 through the inlet connection 17 is conveyed around the cleaner roller 13 a number of times by means of baffles mounted in a correspondingly helical pattern above the cleaner roller 13 and is then conveyed to the outlet 18. The space through which the fiber cotton bundle is directed in a spiral pattern may be referred to as a cleaning chamber 30. After passing through the cleaning chamber 30, the cleaned fibre fleece leaves the cleaner 5 as a fibre fleece stream 25, which is conveyed through the outlet 18 into the additional transport line 6.

A static pressure measuring piece 23 is installed in the inlet connection 17. On the basis of the pressure measuring member 23, the static pressure is sent as an actual value 27 to the controller 26. Upstream of the inlet connection 17, an exhaust duct 19 is connected to the conveying line 4, wherein the air is guided by an exhaust fan 20. The fan 20 is provided with a drive 21 for adjusting the rotational speed of the exhaust fan 20. The exhaust duct 19 carries the air discharged from the transport line 4 by means of the exhaust fan 20 to the exhaust 22 system (not shown) of the spinning preparation system.

Based on the difference between the actual value 27 of the pressure and the predetermined target value 28 of the pressure, a control signal 29 in the controller 26 is output to the driver 21 of the exhaust fan 20. The controller 26 may receive a set value of the target value 28 via a measurement system upstream of the cleaner 5, or the target value may be input into the controller 26 by manual input.

List of reference numerals

1 fiber bag

2 bale breaker

3. 7, 10 transportation fan

4. 6, 9 transport line

5 Cleaner

8 mixer

11 distributor

12 carding machine

13 Cleaner roller

14 beater element

15 direction of rotation

16 grid

17 cleaner inlet

18 outlet of cleaner

19 exhaust pipe

20 exhaust fan

21 driver

22 exhaust

23 pressure measuring element

24 fiber cotton tow stream

25 fiber cotton beam

26 controller

Actual value of 27 pressure

Target value of 28 pressure

29 control signal

30 clean room

Claims

1. An arrangement for adjusting a flow of fibre cotton tow (24, 25) in a cleaner (5) in a spinning preparation system, wherein the arrangement comprises the cleaner (5), a static pressure measuring member (23), an exhaust duct (19) arranged upstream of the static pressure measuring member (23), and a controller, the flow of fibre cotton tow (24, 25) being led in a transport line (4) to an inlet of the cleaner (5) and leaving the cleaner (5) via an outlet (18) after passing a cleaning chamber (30), wherein the cleaner has an inlet connection (17) for connecting the transport line (4), characterized in that a static pressure measuring member (23) is arranged in the flow of fibre cotton tow (24) in the inlet connection (17) or in the transport line (4) upstream of the inlet connection (17), Or in the cleaning room (30), and the exhaust pipe (19) is connected to the transport line (4) and has an exhaust fan (20) with a drive (21), wherein a target value of the pressure is assigned to a predetermined or prevailing operating state of the cleaner (5), and the controller of the drive (21) of the exhaust fan (20) is arranged to adjust the target value of the pressure in the cleaner (5).

2. An arrangement according to claim 1, characterised in that the static pressure measuring member (23) is arranged in the inlet connection (17) of the cleaner (5).

3. The arrangement according to claim 1 or 2, characterized in that the prevailing operating state can be determined from the fibre fleece stream (24) by means of the controller.

4. The device of claim 1 or 2, wherein the predetermined operating state can be set manually on the controller.

5. An arrangement according to claim 1 or 2, characterized in that the static pressure in the cleaner (5) is constant.

6. Device according to claim 1 or 2, characterized in that the exhaust fan (20) is connected to the exhaust system of the spinning preparation system.

7. A method for adjusting a flow (24, 25) of a stream of fibrous cotton in a cleaner (5) in a spinning preparation system, wherein the stream of fibrous cotton (24, 25) is transported by a transport line (4) to an inlet of the cleaner (5) and removed from the cleaner (5) by an outlet (18), wherein the cleaner (5) has an inlet connection (17) for connecting the transport line (4), characterized in that a static pressure is measured in the stream of fibrous cotton (24) in the inlet connection (17) or in the transport line (4) upstream of the inlet connection (17) or in a cleaning chamber (30) of the cleaner (5), and an exhaust pipe (19) is provided in the transport line (4) upstream of the inlet connection (17) and upstream of a static pressure measuring member (23), the exhaust pipe is connected to the transport line (4) and has an exhaust fan (20) with a drive (21), and a target value for the pressure in the cleaner (5) is determined from a predetermined or prevailing operating state of the cleaner (5), and the pressure in the cleaner (5) is adjusted at the target value by controlling the drive (21) of the exhaust fan (20).

8. A method according to claim 7, characterized in that the flow (24) of fibre fleece is fed into the cleaner (5) by means of the inlet connection (17) at a constant feed air flow rate.