CZ308782B6 - Method of regulating the flow or pressure in a waste transport device when preparing fibre and equipment - Google Patents

Abstract

When regulating the flow or pressure of air in a waste transport system when preparing a fibre in which a pipe network comprising a manifold (14) connected to a vacuum source and suction lines (8, 10, 12) connecting the collecting lines (14) to the sequence of cleaning machines (2, 3, 4), sucks air with impurities from individual cleaning machines (2, 3, 4) into the collecting line (14) and the air with the impurities is conveyed to the waste outlet (17) or to the filter box. The air flow in each suction line (8, 10, 12) is regulated separately and at the same time the current air flow is measured in the collecting line (14), comparing the current value of the air flow in the manifold with the desired value of the air flow in the manifold (14) and the suction power of the vacuum source is regulated so that the actual value of the air flow in the manifold (14) corresponds to the desired value of the air flow in the manifold (14).

Description

Method of regulating flow or pressure in a waste transport device in the preparation of fiber and equipment

Field of technology

The invention relates to a method for regulating the flow or pressure in a waste transport device in the preparation of a fiber (cotton mill) with a sequence of cleaning machines.

The invention also relates to a device for carrying out the method.

Prior art

The supplied fibers or tufts of fibers are prepared for use in a spinning machine in the preparation of the fiber in a spinning mill. As part of the fiber preparation, the fibers prepared for the spinning mill take place through a number of processing steps. In the first step, the fibers are extracted in the form of tufts of fibers from fiber bundles. For this purpose, a so-called bale spreader is usually used. By means of the pneumatic conveying of the tufts, these tufts of fibers are removed from the bale disintegrator and are fed, for example, to the following cleaning machine. The preparation of the fiber further comprises a sequence of cleaning machines through which the fibers or tufts of fibers run. In their sequence and construction, the cleaning machines are harmonized with the processed fibers and serve for cleaning, mixing and unification of fiber tufts into individual fibers, as well as for their parallelization. The arrangement of the individual cleaning machines in the preparation of the fiber can be carried out in different ways, this depends, inter alia, on the raw material to be processed and the product to be obtained.

Examples of cleaning machines used are coarse cleaners, fine cleaners, foreign body separators, as well as carding machines. Other machines, such as hoppers or mixing machines, can also be equipped with cleaning modules, which also belong to the cleaning machines. Fibers or tufts of fibers are usually conveyed between machines by a pneumatic conveying system by means of conveying air. In front of the cleaning machines, the supply air is, if necessary, removed by a separate exhaust air system. The cleaning machine itself extracts the so-called waste, which contains dirt particles, foreign bodies, seed or stem particles, dust particles separated in the cleaning process from fibers or fiber tufts, as well as short fibers or fiber nodules, so-called knobs. In cleaning machines, a constant pressure in the conveying air flow through the machine is important for trouble-free operation.

Carding machines, which unify the tufts of fibers into individual fibers and shape them into a strand of fibers, form the conclusion of the preparation of the fiber. After the carding machines, the fibers are transferred in the form of a fiber strand to preparation for spinning. In preparation for spinning, the fiber strands are processed by twisting machines, combing machines or wing machines for use in the final spinning process.

Various proposals for the transport of waste generated in individual cleaning machines are known from the prior art. EP 1841908 A1 describes a foreign particle separator in which waste is led to a waste bag. Furthermore, according to DE 10347006 A1, it is known to transport waste by means of a fan provided exclusively for this purpose from the separation point and for its supply to the central waste disposal. EP 0494181 A1 describes a cleaning machine in which waste is led to a collecting channel. The collecting duct is further emptied mechanically or by means of a continuous stream of conveying air.

The disadvantage of these methods is that the proposed waste transport systems require lengthy and expensive mechanical handling of the generated waste or that it is necessary to discharge the waste with a continuous high suction power.

- 1 CZ 308782 B6

EP 3633086 discloses a method and system for transporting fibers in the preparation of fibers, i.e. a system for transporting fibrous material as a raw material for textile production. So far, the purpose is EP 3633086 focused on the air mode of individual machines and the air mode for transporting fibers between individual machines in sections. In order for the machines to work properly and for the fibers to be transported gradually from one machine to another, it is necessary to maintain a certain air regime both at the inlet of these machines and at their outlet. The system according to EP 3633086 is used for this purpose, in which fans for fiber transport are also connected between the machines and the machines are connected to manifolds, some of which are connected to a suction line with a fan-terminated filter housing. , which is without a fan and is separately connected to the filter box. EP 3633086 describes various combinations of two air manifolds, only one of which has its own fan. EP 3633086 also describes various arrangements for measuring flow or pressure in front of a machine, or behind a machine, etc., with the control of a suction line or a manifold, but always following a pair of air manifolds.

The disadvantage of the solution according to EP 3633086 is its complexity and focus on the air regime of individual machines and on the transport of fibers between them, while there is no focus on the transport of dirt and optimization of dirt transport in terms of automatic operation and energy consumption.

The object of the invention is to provide such a method and device which enables the automatic operation of a waste transport system and at the same time a reduction and optimization of the energy consumption for waste transport can be achieved.

The essence of the invention

The task is solved by a method and a device with the features of independent claims.

To solve this problem, a new method of regulating flow or pressure within a waste transport system in the preparation of a fiber with a sequence of cleaning machines is proposed, and a waste transport system is preferably arranged which comprises a pipeline network consisting of a collecting line and suction lines coming from the collecting machine. a line to the cleaning machines, the collecting line being connected to a vacuum source. The suction lines are equipped with a flow adjusting member and the current flow in the manifold is measured by measuring the flow and the suction power of the vacuum source is regulated by comparing the desired and actual flow value. Measurement methods known in the art, such as a venturi or an anemometer, can be used to measure flow. For the purposes of the application, suction power is defined as the power which a vacuum source must exert in order to create a certain flow under a certain vacuum. In this sense, the suction power at high vacuum and low flow corresponds to the suction power at low vacuum and high flow. For example, if a fan is used as the vacuum source, the suction power is equivalent to the electrical power required to drive the fan to create a certain flow under a certain vacuum.

Among other things, the traffic flow is decisive for the transport performance or the operational safety of the waste transport system. The discharged waste particles are conveyed by the conveying air through the suction lines and the collecting line, it being important that the conveying speed does not fall below a certain level in order to prevent the particles from settling in the lines. On the other hand, in order to avoid an unnecessary increase in energy consumption for safety reasons, the provision of high transport power or suction power which is not required should be avoided. Because the suction lines are provided with a flow adjusting member, such as a baffle, flap or slide, the total flow provided is adequately distributed to the suction line. Due to the cleaning machines that are in operation, the required flow can be determined by the control. The vacuum source is now adequately regulated by comparing the setpoint and actual value so that the most constant flow rate possible is achieved in the manifold.

It is advantageous to provide the at least one suction line with a closing member, wherein before or simultaneously with the opening of the closing member, the suction power of the vacuum source is increased by such an amount that

-2 CZ 308782 B6 which corresponds to the need for suction power after opening the closing member. The advantage of the shut-off element is that cleaning machines that are not in operation can be easily disconnected from the waste transport system, and this does not cause an increase in suction power due to possible leaks without actually having to perform suction. Now, in order not to interrupt the transport of waste by quickly connecting the appliance when the closing member is opened, the suction power of the vacuum source is increased according to the planned opening of the closing member. At the same time, the increase in suction power is carried out according to the expected increase. In this way, greater fluctuations in the total flow of the waste transport system can be prevented, as well as the start of a vacuum check on other cleaning machines.

Preferably, the plurality of suction lines are provided with a closing member and the closing members of the individual suction lines are opened one after the other for a certain time. This cyclic transport of the waste of the individual cleaning machines has the advantage that the maximum value of the required suction power can be kept low, since at the same time the waste of all or more cleaning machines does not have to be transported. Suction cycle times as well as breaks between the suction of different cleaning machines must be adapted to the design of the cleaning machines and their operation and load. It is also possible to try to combine cyclic and continuous operation of individual cleaning machines. For example, cleaning machines, such as a carding machine, can be provided with the continuous transport of waste.

It is advantageous if the suction power of the vacuum source does not fall below the minimum level. This measure ensures that contamination of the waste transport system is prevented. Waste points that must be in continuous operation, such as hand-held suction devices or continuous cleaning devices in carding machines, can also be integrated into the waste transport system.

It is further proposed to prepare a fiber with a sequence of cleaning machines and a waste transport system, the waste transport system comprising a vacuum source and a piping network consisting of a manifold connected to the vacuum source and suction lines extending from the manifold towards the individual cleaning machines. The suction lines are equipped with a flow adjusting member. A flow measurement is preferably arranged in the manifold, or each cleaning machine is alternatively provided with a vacuum control with a pressure sensor and a throttle member. It is advantageous if at least the suction line is provided with a closing member. This makes it possible to disconnect the cleaning machine, which is not in operation, from the waste transport system. For example, gate valves or flaps can be used as closing members. When using a shut-off member provided with a drive, a cyclic connection of the individual cleaning machines to the waste transport system can be achieved for a certain time by opening and closing the shut-off member.

A false air opening is preferably located in the manifold. This makes it possible to control the vacuum source in such a way that a minimum flow is always conveyed, even when most cleaning machines are disconnected from the waste transport system. It is furthermore advantageous if the false air opening is actuated by a vacuum. This means that the false air opening expands as the vacuum in the manifold increases and the false air opening decreases as the vacuum decreases. By means of this device, a strong drop in vacuum can be captured by closing the closing member of the cleaning machine, so that the flow drawn in by the vacuum source is drawn in from the false air opening, at least until the vacuum source control adapts to the new situation.

The vacuum source is preferably a speed-controlled drive fan. Alternatively, the source of vacuum may be a filter housing. So-called filter cabinets are typically installed in spinning mills or in preparation for spinning. In such a filter box, for example, the exhaust air ducts and the suction ducts from the entire spinning mill are brought together. The supply air is cleaned in the filter housing. To prevent environmental pollution, the filter housing is under vacuum. This vacuum is also used directly for suction in the suction devices connected to the filter housing. The respective fan device regulates the filter housing under a certain vacuum and serves as a source of vacuum.

-3GB 308782 B6

Explanation of drawings

The invention is further elucidated on the basis of an exemplary embodiment and is further elucidated with the drawings. These mean:

Fig. 1 is a schematic illustration of the preparation of fibers in a first exemplary embodiment, Fig. 2 is a schematic illustration of the preparation of fibers in a second exemplary embodiment.

Examples of embodiments of the invention

Giant. 1 shows a schematic illustration of the preparation of fibers with a sequence of cleaning machines 2, 3 and 4 in a first exemplary embodiment of the invention. The treated fibers or fiber tufts are led to the coarse cleaner 2 by a fiber supply 1 (not shown). The fibers are fed from the coarse cleaner 2 to the fine cleaner 3 via a conveying line 5 and from there by a conveying line 6 from the carding machine 4. , have been subjected to various stages of cleaning and treatment, leaving the carding machine 4 in the form of a strand 7 of fibers for further treatment. The waste generated by the treatment of the fibers is discharged in the waste transport system from the individual cleaning machines 2, 3 and 4. Common to the fiber preparation shown is the waste transport system with a vacuum source. In the exemplary embodiment shown, the vacuum source is formed by a fan 16. The waste transport system comprises a collecting line 14 emerging from the fan 16 and a suction line 8, 10 and 12 extending from the collecting line 14, which are connected to a cleaning machine 2, 3 or 4. In the illustrated embodiment, the coarse cleaner 2 is sucked through the suction line 8, the fine cleaner 3 through the suction line 10 and the carding machine 4 through the suction line 12 is connected to the collecting line 14. The waste is sucked in by the vacuum source or the fan 16. 17 waste.

Air flow adjusting members 9, 11 and 13 are preferably arranged in the individual suction lines 8, 10 and 12. These serve to divide the total flow of air drawn in by the fan 16 into the individual cleaning machines 2, 3 and 4, as required. In the collecting line 14, a flow meter 15 is located in front of the fan 16 to measure the current flow. Due to the cleaning machines that are in operation and their mode, as well as depending on the fibrous material being processed, the air flow in the manifold 14 is set by manually entering or controlling the setpoint specifier 19. The fan 16 is thus regulated by the setpoint 18 and setpoint comparator 18. so that the measured actual air flow corresponds to the specified required flow.

Giant. 2 shows a schematic illustration of the preparation of fibers with a sequence of cleaning machines 2, 3 and 4 in a second exemplary embodiment. The arrangement of the cleaning machines 2, 3 and 4 is identical to that of Fig. 1. The waste transport system comprises a collecting line 14 which is connected to a fan 16 serving as a vacuum source. A flow meter 15 is preferably arranged in the manifold 14, by which the current air flow in front of the fan 16 is measured. The suction power of the fan 16 is regulated by the comparator 18 as described in the embodiment in FIG. suction lines 8, 10 and 12 to the individual cleaning machines 2, 3 and 4. The suction line 8 connects the collecting line 14 to the coarse cleaner 2 and the suction line 10 connects the collecting line 14 to the fine cleaner 3. An adjustment line is arranged in the suction lines 8 and 10. the air flow member 9 and 11, as well as the closing member 31 and 32. The flow adjusting member 9 or 11 prevents the air flow member 31 and 11, respectively, from being opened. 32, too high, and thus the need for the respective cleaning machine 2, resp. 3, to a non-adapted flow in the suction line 8 or 10. By lowering the closing members 31 and 32, it is further possible to cycle the waste from the fine cleaner 2, respectively. of the coarse cleaner 3. In cyclic operation, the position of the closing members 31 and 32 is included in the setpoint specifier 19 for fan control. This prevents the suction power of the fan 16 from being too low or too high and allows optimized operation. In order to be able to catch the power peaks, a false air opening 30 is advantageously arranged in the collecting line 14.

-4GB 308782 B6

The suction line 12, which connects the carding machine 4 to the collecting line, is provided with a vacuum monitor with a pressure sensor 27, which measures the existing vacuum in the suction line 12. This measured value is transmitted to the vacuum controller 20 and compared with the value determined for specific operation of the carding. 5 of the machine 4. Depending on this comparison, the throttle member 28 closes, resp. opens, in order to adjust the vacuum in the suction line 8. This is due to the fact that the carding machine 4 typically requires constant suction of waste and cannot be sucked out cyclically. However, the intended flow control in the header is a combination of cyclic and constant waste transport within a single waste transport system.

The invention is not limited to the embodiments shown and described. Variations as well as combinations of features are possible within the scope of the claims, although these are shown and described in various exemplary embodiments.

Claims (10)

PATENT CLAIMS A method of regulating the flow or pressure of air in a waste transport system in the preparation of a fiber, wherein a pipe network comprising a manifold (14) connected to a vacuum source and a set of suction lines (8, 10, 12) connecting the manifold (14). ) with a sequence of cleaning machines (2, 3,4), sucks air with dirt from the individual cleaning machines (2, 3, 4) into the collecting line (14) and the air with dirt is transported to the waste outlet (17) or to the filter box , characterized in that in each suction line (8, 10, 12) the air flow is regulated separately during the suction of air with impurities and at the same time the current air flow is measured in the collecting line (14), comparing the current air flow value in the manifold (14) with the desired value of the air flow in the manifold (14) and the suction power of the vacuum source is regulated so that the actual value of the air flow in the manifold (14) corresponds to the desired value of the air flow in the manifold (14). Method according to claim 1, characterized in that during the suction of air with impurities from the individual cleaning machines (2,3,4) into the collecting line (14), the opening or closing of at least one suction line (8, 10) is controlled for the flow of air from the cleaning machine (2, 3) to the manifold (14), wherein before or simultaneously with the opening of this suction line (8,10) the suction power of the vacuum source is adapted to the expected increase in suction power demand after opening at least one suction line (8). , 10). Method according to claim 2, characterized in that during the suction of air with impurities from the individual cleaning machines (2, 3, 4) into the collecting line (14), the closing and opening of at least two suction lines (8, 10) for the flow of air from the cleaning machine (2, 3) to the collecting line (14), the opening and closing of the individual suction lines (8, 10) being carried out separately from one another and always only for a certain time. Method according to one of Claims 1 to 3, characterized in that the suction power of the vacuum source is regulated so that the actual suction power is always above the minimum level of the suction power of the vacuum source. 5. Fiber preparation plant with a sequence of cleaning machines (2, 3, 4) and with a system for transporting waste from cleaning machines (2, 3, 4) to waste, where the waste transport system comprises a vacuum source and a pipeline network, where the pipeline the network comprises a collecting line (14) connected to a vacuum source and further comprises suction lines (8, 10, 12) which connect the collecting line (14) to the individual cleaning machines (2, 3, 4), characterized in that each suction line the duct (8, 10, 12) is provided with an air flow control member and at least one air flow sensor (15) is arranged in the manifold (14), the at least one air flow sensor (15) in the manifold (14) being coupled to the comparator (18) of the desired and actual value of the air flow and the comparator (18) is coupled to a vacuum source (16). Device according to claim 5, characterized in that the air flow control members are formed by air flow adjusting members (9, 11, 13) and the air flow setpoint and actual air value comparator (18) is coupled to the air flow setpoint specifier (19). . Device according to Claim 5, characterized in that the air flow control members of the at least one suction line (8, 10) are formed by an air flow adjusting member (9, 11) behind which a suction line (8, 10) is arranged. the closing member (31, 32) of this suction line (8, 10) and the air flow control member of the at least one suction line (12) is formed by a vacuum regulator (20) with a pressure sensor (27) and a throttle member (28), the comparator (18) is coupled to the airflow setpoint specifier (19) and the specifier (19) is further coupled to the intake manifold closure members (31, 32) (8, 10). -6GB 308782 B6 Device according to any one of claims 5 to 7, characterized in that a false air opening (30) is arranged in the collecting line (14). Device according to Claim 8, characterized in that the false air opening (30) is designed as a vacuum-controlled opening (5) with a variable flow rate. Device according to at least one of Claims 5 to 9, characterized in that the vacuum source is a fan (16) connected to a speed-controlled drive or a filter housing.