Carding machine

Abstract

The invention relates to a carding machine (K) with an inlet side for fiber flakes, wherein the carding machine is designed to feed the fiber flakes to a rotating drum (4) by means of rollers, wherein the fiber flakes are broken down, aligned and cleaned between fixed carding elements and circulating cover bars (14) and the drum down to the individual fiber, and the resulting fiber sliver can be transferred from the drum (4) to a receiver (5), to which a device for converting the fiber sliver into a fiber ribbon is arranged, followed by a compressor funnel (10) with a pair of take-off rollers (11, 12) for depositing the fiber ribbon in a can (15).The invention is characterized in that an air channel (20) with inlet and outlet openings (20a, 20b) for guiding the fiber ribbon in the transport direction is arranged between the device for converting (17) the fiber fleece into a fiber ribbon and the compressor funnel (10), wherein the air channel extends essentially vertically to the transport direction of the fiber ribbon and has on its upper side a device (25) which is designed to direct the airflow in the air space of the fleece take-off (18) into the upper carding chamber and simultaneously guide the air flowing through the fiber ribbon into the air channel (20).

Description

[0001] The invention relates to a carding machine with an inlet side for fiber flakes, wherein the carding machine is designed to feed the fiber flakes to a rotating drum by means of rollers, wherein the fiber flakes are opened up to the individual fiber, aligned and cleaned between fixed carding elements and rotating flat bars and the drum, and the resulting fiber web can be transferred from the drum to a doffer, which is followed by a device for converting the fiber web into a fiber sliver, which is followed by a compacting hopper with a pair of take-off rollers for depositing the fiber sliver in a can.

[0002] According to the state of the art in the field of textile technology, it is known in the carding machine for treating cotton, chemical fibers, or the like to use a device to deform the fiber web into a fiber sliver after the squeeze rollers. This device can be designed as a funnel, roller arrangement, or cross-belt take-off. The fiber sliver is then guided via a funnel-shaped, round web guide element to a compacting funnel, and then fed via take-off rollers to a can frame. Due to the design, gaps are arranged between the cross-belt take-off and the web guide element, through which an air flow is created in the gaps due to the air flow within the carding machine.In the gap between the fleece guide element and the compaction hopper, an airflow is also generated by an extraction system. This draws air from the gaps between the cross-belt take-off and the fleece guide element, disrupting the air flow there and preventing the cleaning effect of the prevailing airflow. This leads to unwanted fiber deposition in the areas not exposed to the airflow, so that fiber residues and individual flock clumps occasionally adhere to the fiber sliver and create an undesirable material accumulation or compaction.

[0003] When processing fiber blends made from recycled cotton with shreds and cotton flakes, fiber blends with very different fiber lengths are created. Recycled cotton can have a fiber length of 14 to 28 mm, shreds a fiber length of 14 to 18 mm, whereas cotton fibers have a sliver length of 22 to 35 mm, depending on the type. For example, after the cross-belt take-off, where the fiber web is gathered and subsequently formed into a fiber sliver, short fibers collect on the components guiding the sliver between the cross-belt take-off and the compactor hopper, which is located in front of the take-off rollers. Once the fiber lumps reach a certain quantity or size, this accumulation of short fibers is sucked in through the chimney between the cross-belt take-off and the compactor hopper and carried along by the formed fiber sliver. Local thick spots develop in the sliver, which can subsequently lead to sliver breakage.In observations on cards that process other fiber blends - e.g. cotton with viscose or lyocell - this problem also always occurred when fiber blends with fibers of different lengths were processed. These unwanted fiber accumulations occur more frequently, especially when using recycled fibers and / or fibers from shredded material with a fiber quality that has significantly longer fibers. Shortening the distance between the cross belt take-off and the compactor hopper does not completely eliminate this problem. The unwanted fiber accumulations only occur with a time delay. The increased use of recycled fibers or fibers from shredded material results in increased demands on the roving machines to ensure that they can continue to operate smoothly and at high productivity in the future.

[0004] DE 102019132606 A1 discloses an air duct located between the cross-belt take-off and the web funnel. This achieves an asymmetrical air flow, as the air drawn in and discharged is directed laterally to the fiber sliver's passage opening.

[0005] SU 291576 discloses an air duct in front of an extraction funnel, where the air to be extracted is discharged through a separate exhaust pipe below the duct. A disadvantage is the extraction of fibers in the outer region of the fiber sliver being formed.

[0006] Accordingly, the invention is based on the object of developing a spinning preparation machine in such a way that material accumulations between the cross belt and the compaction hopper are avoided.

[0007] The invention solves the stated problem by a device having the features specified in claim 1. Advantageous developments of the invention are defined in the dependent claims.

[0008] The card according to the invention has an inlet side for fiber flakes, wherein the card is designed to feed the fiber flakes to a rotating drum by means of rollers, wherein the fiber flakes are opened up to the individual fiber, aligned and cleaned between fixed carding elements and rotating flat bars and the drum, and the resulting fiber web can be transferred from the drum to a doffer, which is followed by a device for converting the fiber web into a fiber sliver, which is followed by a compaction hopper with a pair of take-off rollers for depositing the fiber sliver in a can.

[0009] The invention includes the technical teaching that an air duct with inlet and outlet openings for passing the sliver in the transport direction is arranged between the device for converting the fiber web into a sliver and the compactor funnel, wherein the air duct extends substantially vertically to the transport direction of the sliver and has on its upper side a device which is designed to guide the air flow in the air space of the web take-off into the upper carding space and at the same time to guide the air flowing through the sliver into the air duct.

[0010] The device has the advantage that the air flow in the air space of the web take-off is directed into the upper carding space. It therefore no longer flows vertically down the air duct. At the same time, the air entrained by the fiber sliver is guided into the air duct. This separates the air flows, preventing fibers from sticking together and the associated tearing of fiber lumps.

[0011] The fact that the device is designed as an extraction funnel with a guide surface inclined downwards from the horizontal and oriented toward the device for converting the fiber web into a fiber sliver achieves a separation of the air flows. The air flow in the air space of the web take-off, which is oriented opposite to the transport direction of the fiber sliver, is separated from the air flow generated by the fiber sliver.

[0012] The orientation of the guide surface, which is inclined downwards at an angle of 20° to 40° to the horizontal, has proven advantageous. In conjunction with a cross-belt take-off system, the guide surface can extend into the area of ​​the roller shaft. Even when using rollers or hoppers, the inclination has the advantage of guiding the air flow in the air space of the fleece take-off at a constant speed.

[0013] The guide surface can be tapered to a flattened tip that extends into the area of ​​the device for converting the fiber pile into a fiber ribbon. This effectively shields the two air flows from each other.

[0014] The extraction hopper has an opening below the guide surface through which air flowing through the fiber sliver is guided into the air duct. The air flow is then discharged along with the fiber sliver through the compressor hopper. This prevents a build-up of uncontrolled airflow.

[0015] The suction funnel can be designed to be inserted into an upper opening of the air duct. This allows for retrofitting existing carding machines without great effort.

[0016] Further measures improving the invention are described in more detail below together with the description of a preferred embodiment of the invention with reference to the figures.

[0017] They show: Fig. 1 is a schematic side view of a carding machine in which the device according to the invention is used; Fig. 2 is a detailed enlargement of the area after the cross-belt take-off according to the prior art; Fig. 3 is a lateral sectional view through an air duct with the suction funnel according to the invention; Fig. 4 is an enlarged front view of a part of the air duct in a partial section.

[0018] Below, with reference to the Fig. 1 to 4 Preferred embodiments of the carding machine according to the invention are explained below. Identical features in the drawings are provided with the same reference numerals. It should be understood that the drawings are merely simplified and, in particular, are not drawn to scale.

[0019] The carding machine K according to Fig. 1is shown in a simplified schematic side view. Fiber flakes are guided via a shaft to a feed roller 1, a feed table 2, via several licker-in devices 3a, 3b, 3c to the drum 4 or the reel tambour. On the drum 4, the fibers of the fiber flakes are parallelized and cleaned by means of fixed carding elements (flat bars) 14 arranged on a revolving flat 13 rotating around flat deflection rollers 13a, 13b. The resulting fiber web is then conveyed via a doffer 5, a doffer roller 6 and several squeeze rollers 7, 8 to a web guide element 9, which forms the fiber web into a fiber sliver with a compactor hopper 10. The fiber sliver is transferred via take-off rollers 11, 12 to a downstream processing machine or a can 15 with can frame 16. M denotes the center point (or the bearing axis) of the drum 4. The arrow A indicates the working direction in relation to the fiber material or fiber fleece.The rotation directions of the rollers are shown in . Fig. 1 indicated by curved arrows, where arrow 4b indicates the direction of rotation of the drum 4. C indicates the direction of rotation of the revolving flat 13 in the carding position, and D indicates its return transport direction.

[0020] Figure 2shows the prior art with an enlarged view of the area between the squeeze rollers 7, 8 and the take-off rollers 11, 12, without the fiber sliver or fiber web. The fiber web is taken over by the squeeze rollers 7, 8 from the doffer roller 6 (not shown here) and formed into a fiber sliver by the cross-sliver take-off 17. From the cross-sliver take-off 17, the fiber sliver passes through the web guide element 9, which in this embodiment is designed as a baffle or funnel with a tapered cross-section, is then guided to the compactor funnel 10 and, after the compactor funnel 10, is guided out of the card through the take-off rollers 11, 12. Due to the arrangement and fastening of the components, an air duct 20 with an approximately square or rectangular cross-section is arranged between the web guide element 9 and the compactor funnel 10, which extends at least partially vertically and thus orthogonally to the working direction of the fiber sliver.The air duct 20 has an inlet opening 20a for the fiber sliver, at which the web guide element 9 is arranged. The air duct 20 also has an outlet opening 20b for the fiber sliver, behind which the compactor hopper 10 is arranged, as seen in the transport direction. The inlet opening 20a and the outlet opening 20b are aligned or on a line of symmetry. Due to the air flow in the gaps of the card and the air extraction in the gap between the web guide element 9 and the compactor hopper 10, a high air flow is created in the air space of the web take-off 18 below the flap 19. This air flow flows past the openings of the air duct 20 and, together with the air extraction in the gap between the web guide element 9 and the compactor hopper 10, creates a negative pressure within the air duct 20. The air duct 20 acts like a chimney, with the negative pressure pulling fibers and fiber clumps out of the fiber pile running transversely to the air flow.These fibers and fiber clumps are deposited on the profile above the squeeze rollers 7, 8 in the air space of the fleece removal 18.

[0021] For piecing, first the flap 19 is opened and then the air duct 20 with the compactor hopper 10 and the take-off rollers 11, 12 with the complete housing of the piecing device 22 is pivoted downwards. The operator removes the sliver manually from the cross-sliver take-off 17 and guides it into the fleece guide element 9. The air duct 20 arranged behind it can be covered on the top side with a removable closure 21. By means of air nozzles (not shown), the sliver is conveyed through the compactor hopper 10 between the take-off rollers 11, 12. If the sliver is grasped by the take-off rollers 11, 12, the previously pivoted downwards components with the housing of the piecing device 22 are returned to their original position ( Figure 2). The air duct 20 is arranged symmetrically to the transport direction of the fiber sliver across the working width.

[0022] Figure 3 and 4shows the device according to the invention in the form of a suction funnel 25, which is inserted into the upper opening of the air duct 20 and fastened. The suction funnel 25 corresponds in cross-section to the cross-section of the air duct 20, with three sides of the suction funnel 25 forming a closed surface. The fourth surface, directed forward towards the cross-belt take-off 17, is designed as an opening 25b through which the air flow directed by the cross-belt take-off 17 is guided into the air duct 20. A guide surface in the form of a roof-like overhang 25a is inclined downwards at an angle of 20° to 40° to the horizontal and directed towards the cross-belt take-off 17. Instead of the cross-belt take-off 17, a funnel or a roller arrangement can also be used to transform the fiber web into a fiber band. Regardless of the use of the cross-belt take-off 17, an air flow is entrained by the resulting fiber band, which flows towards the air duct 20.In a perspective front view of the . Figure 4 it can be seen that the roof-like projection 25a tapers to a flattened tip which projects into the area of ​​the deflection rollers of the cross belt take-off 17.

[0023] The air flow in the air space of the web take-off 18 is diverted by the guide surface, i.e. the roof-like overhang 25a, so that the air flow is not guided along the air duct 20 vertically down to the web guide element 9, but into the upper carding space. At the same time, the rotation of the cross-belt take-off 17 with the fiber sliver creates an air flow onto the web guide element 9, which is guided through the opening 25b under the roof-shaped overhang 25a into the suction funnel 25b, thereby entraining fiber accumulations above the cross-belt take-off 17. The air flow in the air space of the web take-off is thus kept away from the fiber sliver. At the same time, the air flow generated by the cross-belt take-off 17 is diverted onto the web guide element 9 in such a way that fiber accumulations above the cross-belt take-off 17 are continuously sucked into the air duct 20. Reference symbol:

[0024] Card 1Feed roller 2Feed table 3a, 3b, 3cLicker-in roller 4Drum 4bDirection of rotation (of drum 4) 5Doffer 6Doffer roller 7, 8Squeeze roller 9Web guide element 10Compaction hopper 11, 12Take-off rollers 13Revolving flat 13a, 13bFlat deflection rollers 14Flat rods 15Can 16Can frame 17Cross belt take-off 18Air space for web take-off 19Flap 20Air duct 20aInlet opening 20bOutlet opening 21Closure 22Piping device housing 25Suction funnel 25aProtrusion 25bOpening AWorking direction CRotation direction (of the revolving flat 13) DReturn transport direction (of the flat bars 14) MCenter point or bearing axis (of the drum 4)

Claims

1. Carding machine (K) with an inlet side for fibre flocks wherein the carding machine (K) is configured to feed the fibre flocks to a rotating cylinder (4) using rollers, wherein the fibre flocks are opened to individual fibres, aligned and cleaned between fixed carding elements and revolving flat bars (14) and the cylinder (4) and the fibre web produced in the process is transferable from the cylinder (4) to a doffer (5), downstream of which there is a device for converting the fibre web into a fibre sliver, downstream of which a condenser funnel (10) with a pair of delivery rollers (11, 12) for coiling the fibre sliver in a can (15) follows, wherein an air duct (20) with inlet and outlet openings (20a, 20b) is arranged between the device for converting the fibre web into a fibre sliver and the condenser funnel (10) is arranged for directing the fibre sliver through in the direction of conveying, wherein the air duct (20) essentially extends vertically to the direction of conveying of the fibre sliver and, on the upper face, features a device which is configured to direct the air flow in the air compartment of the web doffing (18) into the upper carding compartment and simultaneously direct the air flowing through the fibre sliver along with it into the air duct (20), characterised in that the device is configured as a suction funnel (25) with a guiding surface which is inclined downwards out of the horizontal plane and is aligned in the direction of the device for converting the fibre web into a fibre sliver, and that the suction funnel (25) comprises an opening (25b) underneath the guide surface through which air flowing through the fibre sliver along with it is discharged into the air duct (20) and with the fibre sliver through the condenser funnel (10).

2. Carding machine (K) according to claim 1, characterised in that the guide surface is inclined downwards at an angle of 20° to 40° in relation to the horizontal plane.

3. Carding machine (K) according to claim 2, characterised in that the guide surface tapers to a flattened tip which protrudes into the area of the device for converting the fibre web into a fibre sliver.

4. Carding machine (K) according to claims 1 to 3, characterised in that the suction funnel (25) is configured to be inserted into an upper opening of the air duct (20).

5. Carding machine (K) according to any of the preceding claims, characterised in that the device for converting the fibre web into a fibre sliver is configured as a roller, funnel or transverse belt delivery unit.

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