EP0736619A1 - Pneumatic insertion of sliver to the nip of calander discs - Google Patents

Abstract

To feed sliver to the gap between calender discs, an airstream without air loss is directed through ≥ 2 jet sections (30,60) in the sliver guide to a point directly in front of the clamping gap (100c) between the two calender discs (100a,100b). The action moves the leading end of the sliver automatically, without mechanical feed, to be laid directly in front of the disc clamping gap (100c). Also claimed is a sliver funnel unit where the dia. (d) of the cylindrical front section (31) is generally smaller than the width (b) of the calender discs (100a,100b). The guide channel (31,32) has no side air escape openings.

Description

The technical field of the invention is textile machines. In this area, a section is particularly affected which has a calender device after the drafting device, which usually consists of two opposing calender disks with which the sliver is compacted. Both are described in DE 295 10 871 U1 dated July 5, 1995. Reference is made in full to this disclosure, in particular to claim 1 therein, which is further developed here.

Before the drafting system, several slivers are usually duplicated to form one sliver. The duplicated sliver is conveyed into the drafting system. During the drafting process, the sliver is spread out to form the nonwoven and is thus conveyed by the pair of delivery rollers of the drafting system. The nonwoven must be shaped into a sliver again. This is done with the fleece funnel. When the fiber fleece enters the mouth of the fleece funnel, a fiber band is formed again.

It is known in the prior art that a pair of delivery rollers is arranged at the exit of a drafting system of a draw frame (as an example of a sliver processing machine) which conveys this nonwoven into a fleece funnel. The nonwoven fabric is combined in the nonwoven funnel and shaped again through the funnel mouth to form a sliver and transported on to a sliver tube that has a considerable length. At the end of the sliver tube, the sliver is introduced into a sliver funnel, which determines the conveying direction of the The sliver is deflected by about 90 ° and inserted between a pair of calender rollers (calender discs). After passing through the pair of calenders rollers, the fiber sliver compacted there is conveyed on to the laying device of the draw frame (cf. for example EP 593 884 A1, US 4,372,010 or DE-A 26 23 400).

In DD 290 697 , fleece funnels and belt funnels are considerably spaced apart via a fiber sliver tube. A ventilation opening (there 13) allows the air flowing in at the beginning of the collecting pipe (there 5) to escape completely in front of the narrowest point of the belt funnel, in order to build up a suction stream again shortly thereafter, which is caused by an injector bore in the non-woven channel section with the smallest diameter due to incoming compressed air is built up.

The invention is based on the task of automatically introducing the beginning of the nonwoven into the sliver channel between the delivery rollers and calendering disks and placing it directly in front of the nip of the calendering disks, in particular in an economical manner from the air balance of the guide air.

This object is achieved according to claim 1 or claim 5.

The method according to claim 1 avoids a lateral escape of an air flow which is guided in the laterally airtight guide channel through at least two nozzle sections of the sliver guide. The loss-free guidance air is generated via injector bores which are provided in the cylindrical section of the band funnel shortly before the clamping gap of the calender discs, the cylindrical section mentioned ending in a pointed end of the band funnel which lies directly in front of the clamping gap (claim 5). The diameter of the cylindrical section is considerably smaller than the width of the calender disks that calender the sliver conveyed to them.

In the following, one speaks of a pair of calender disks or the calender disks, whereby a pair of calender rolls is also included under this term. This is possible because a pair of calender disks is not a restriction for the invention compared to a pair of calender rolls.

The diameter of the cylindrical section can be less than a third of the width of the calender disks or be described differently: the calender disks are at least three times wider than the diameter of the narrowest section of the band funnel (claim 4, claim 6).

The method works both with a closed nip and with an open nip (claim 3).

In order to get very close to the clamping gap with the band funnel and its guide channel, the front end tapers and ends in a line (claim 7); curved line sections of the front end of the band funnel, which are adapted to the curvature of the surface of the calender discs, also end in this line. The pointed end can correspond to the width of the clamping gap (claim 10).

With the invention, the faster and safer processing is achieved by eliminating the long sliver tube of the prior art, with which the fleece funnel and the sliver funnel are arranged directly one behind the other. This corresponds to the management facility.
It will be possible to speed up, simplify the processing - i.e. the introduction of the drawn fiber sliver - and reduce the losses in the air budget as much as possible. By eliminating the sliver tube, the sliver guide according to the invention is particularly short and compact. Long distances and therefore unpleasant dead times in terms of control technology can be reduced. Despite its compact design, the fiber guide according to the invention is easy to handle and even allows two positions of the assembled nozzles via the airtight joint (claim 9), one for normal operation and one for processing. Surprisingly, the compact sliver guide is nevertheless easy to adjust and is easy to maintain and operate. Despite the compact design of the guide device, the nozzle inserts can be exchanged in order to enable a quick changeover when changing lots.

The almost completely loss-free air flow from the fleece funnel to the clamping gap of the calender discs is characteristic of the automatic introduction of the fiber fleece into the fiber ribbon guide channel of the textile machine with air. The air flow is guided from the fleece funnel (which rolls up and brings together the stretched fiber fleece) to the belt funnel (which causes the sliver to compress in front of the pair of calender discs) without any losses. In this area there is no lateral opening in the guide channel from which the air could escape; In this area there are only lateral inflow holes (injector holes) that cause and maintain the air suction flow.

Due to the air duct closed up to the clamping line, the method for automated insertion of the beginning of the nonwoven fabric is very economical in terms of its air balance. At the same time, the method is insensitive to pressure fluctuations in the compressed air used for the introduction and can work reliably in a large compressed air range.

By inclined insertion in the sliver conveying direction, the compressed air becomes a suction flow formed above.

A mechanical threading of a section of the nonwoven fabric into the nonwoven funnel is completely eliminated. The fiber fleece only has to be reduced to a smaller width at the front end (to width F1) and the remaining narrower section has to be shortened to a predetermined length, which results from the weight of the fiber fleece and the length of the fiber channel from the fleece funnel to the clamping gap ( on length H). Briefly switching on a compressed air generator to generate a short pulse of compressed air causes the narrowed section of the nonwoven fabric to be threaded into the nonwoven funnel and the section to be transported in front of the nip where, with a brief angular momentum of the calender disks, the complete threading or the complete insertion of the sliver between them Calender discs is reached.

The compressed air pulse can advantageously be coupled with a slightly shifted angular momentum, so that the operator only needs to press a button to thread the nonwoven fabric. In the prior art, a fiber fleece cannot be presented, introduced and brought into the operating position in a simpler, faster and more reliable manner.

The suction flow above the location of the introduction of the compressed air is reliably formed when the compressed air is introduced at the location of the sliver transport channel that has the smallest diameter. This is the band funnel, which is arranged close to the calender discs. A compressed air flow introduced here in the direction of the calender disks results in a reliable suction flow above the point of insertion up to the fleece funnel, since there are no air losses.

In the entire guide section from the fleece funnel to the belt funnel, no openings are provided which are oriented transversely to the guide channel and which could allow air to escape. The reliable construction of the suction flow starting from the foremost end of the conveyor line, retrospectively to the point of entry of the spread fiber sliver - the fleece funnel - makes it possible that no additional inflow of air needs to take place in this area, as is usually the case in the prior art , if a compressed air inflow is provided on the fleece hopper or shortly thereafter, but a vent is provided on the belt hopper or shortly beforehand.

With the invention, the fiber fleece is gripped at the front end by the air flow, then drawn as a fiber sliver along the entire fiber sliver channel and placed directly up to the calender disks. The sliver is not "pushed" by compressed air and is vented far in front of the calender discs.

Figur 1

ist in Überlagerung eine übliche Gestaltung einer Faserband-Führung mit langem Faserbandrohr (linke Bildhälfte) und eine erfindungsgemäße, kompakte Bauweise (rechte Bildhälfte) mit zusammengesteckten Düseneinsätzen 30, 40, 50, 60, wovon zwei Düseneinsätze 40, 50 kippbar gegenüber den anderen beiden Düseneinsätzen 30, 60 sind, die an einem fest oberhalb der Kalanderscheiben 100a, 100b angeordneten Düsenhalter 20 angeordnet sind. Die überlagerte Darstellung dient der Veranschaulichung der Verkürzung des Transportweges. Die Umlenkwalze 71 gehört zum kompakten Aufbau des rechten Bildteiles.

Figur 2

zeigt die Vorbereitung des Faservlies F zum Einführen in den Vliestrichter 50.

Figur 4a, Figur 4b und Figur 4c

zeigen als Vergrößerung der Figur 1 den Bandtrichter 30, der die strömende Führungsluft ohne Verluste bis direkt an den Klemmspalt 100c heranführt.

Figur 5a und Figur 5b

zeigen das Schwenken eines Vliestrichters mit Düsen-Einsatz 40' und einer Kalanderscheibe 100b um einen gemeinsamen Schwenkpunkt SP.

An execution example of the invention is to expand your understanding and deepen.

Figure 1

superimposed is a common design of a sliver guide with a long sliver tube (left half of the picture) and a compact design according to the invention (right half of the picture) with nozzle inserts 30, 40, 50, 60 fitted together, of which two nozzle inserts 40, 50 can be tilted relative to the other two nozzle inserts 30, 60, which are arranged on a nozzle holder 20 arranged fixedly above the calender disks 100a, 100b. The overlaid representation serves to illustrate the shortening of the transport route. The deflection roller 71 belongs to the compact structure of the right part of the picture.

Figure 2

shows the preparation of the fiber fleece F for insertion into the fleece funnel 50.

Figure 4a, Figure 4b and Figure 4c

show the enlargement of Figure 1, the band funnel 30, which leads the flowing guide air without losses up to the clamping gap 100c.

Figure 5a and Figure 5b

show the pivoting of a fleece funnel with nozzle insert 40 'and a calender disk 100b around a common pivot point SP.

The overlay in FIG. 1 illustrates the difference from the prior art, which is shown schematically in FIG. In the prior art, the sliver FV not yet stretched during insertion is introduced into a long guide tube 8, which opens into a sliver funnel 9, via stretching rollers 68a, 68b, 69a, 69b and delivery rollers 70a, 70b by means of a fleece funnel 1. The sliver funnel deflects the fiber sliver FB about 90 ° into the nip of the calender with its calender discs 100a, 100b. The calendered fiber sliver KF emerges vertically downwards from the calender and is stored in a depositing device. This sliver guide is also illustrated in FIG. 2 with the same reference number.

An embodiment of the invention shortens the sliver path and eliminates the sliver tube 8. An additional deflection roller 71 is added, which causes a deflection of approximately 60 ° in the nonwoven conveying direction FV and introduces the fiber sliver into one of several functional elements - forming the sliver channel. The first element is the fleece funnel 50 with a ramp surface 50b and a funnel section 50a arranged directly thereon, in which the broadly arriving fiber sliver (also referred to as fiber fleece) is folded, folded over and introduced into a first channel section. The channel section is formed by an insert 40, which is inserted on the rear side of the funnel section 50a of the fleece funnel 50 and fastened with a screw.

At the front end of the insert 40, an articulated surface is provided which, in the angular position shown in FIG. 1 , enables the guide channel to be sealed off from the subsequent band funnel 30.

The articulated surface of the front, cylindrical section of the inner insert 40 consists of two backward-narrowing, continuously curved surface sections which engage in a corresponding bearing surface 35 on the belt funnel 30. Swiveling the fleece funnel 50 in the direction α into the other end position releases the radially airtight seal between the fleece funnel and the band funnel not, a radially airtight sliver guide is achieved both in the swung-in and in the swung-out state.

The radial tightness on the joint surfaces 35 is adjustable. For this purpose, the upper part - above the articular surface - can be changed in the axial direction, in particular also in the radial direction, in its position relative to the lower part. The fixed holder 20, in which the belt funnel is inserted, forms the basis for the adjustment.

If the fleece funnel 50 is designed in two parts - with an insert inserted into the funnel bore of the fleece funnel in the opposite direction of the sliver conveying direction - the aforementioned relative adjustment can be carried out on a handle 51.

The band funnel 30 is designed as an insert and, with a tapering V-shaped end, engages between the calender disks 100a, 100b as far as the clamping gap 100c. The insert 30 is designed so that it can be inserted and held axially in a band funnel holder 60.

The fiber sliver is conveyed through the fleece nozzle 50, the inner insert 40 and the belt funnel 30 into the guide channel up to the clamping gap 100c, for which purpose the fleece funnel 50 is swung out. The sliver part F1 which is narrowed by hand according to FIG. 3 and held in the funnel mouth 50a is sucked in via injector bores 34a, 34b, 64a, 64b on the belt funnel. A short suction flow in the order of 500m / sec. It is sufficient to convey the narrowed sliver F1 up to the clamping gap 100c with the least amount of compressed air, since the joint bearing surface 356 and the joint surface of the inner insert 40 are radially airtight. Mechanical insertion aids are not required.

In order to introduce the fraction F1 of non-woven fabric and with it the full width F of the non-woven fabric at the entrance to the fleece funnel and to convey it as a reshaped sliver through the nip, a short angular momentum of duration T _{2 is} applied to the calender disk.

It can switch itself on after a predetermined suction time T ₂ , can be superimposed on it or can be initiated separately manually.

The shape of the band funnel 30 can be seen more clearly in FIG. 4a , where the direction and arrangement of the injector bores 34a, 34b in the band funnel are also shown enlarged. They open into a cylindrical channel 31, which forms the front end of the sliver channel. The cylindrical section 31 widens via a conical section 32 to the diameter of the sliver channel, which is predetermined by the inner insert 40.

The inclined injector bores 34a, 34b can run at an angle of approximately 45 ° with respect to the axis 200b of the band funnel insert 30; they can be offset in parallel to give the inserted sliver a twist and additional strength.

A band funnel holder 60 has a central, approximately cylindrical opening into which the band funnel insert 30 is inserted. In the circumferential direction, an annular channel 33, which can be supplied with compressed air from two or more cylindrical bores 64a, 64b, extends inwardly in the cylindrical opening. Starting from the ring channel, the compressed air introduced from the outside is introduced into the aforementioned inclined injector bores 34a, 34b with the band funnel insert 30 inserted, in order to open into the cylindrical section 31 of the fiber band channel, which lies close to the clamping gap 100c.

The front end of the insert 30 is V-shaped with slightly curved V-legs, which are adapted to the surface of the calender rolls 100a, 100b in their curvature. The band funnel insert 30 can thus be inserted directly into the slightly curved space between the calender discs and the cylindrical section 31 ends with its front end directly in front of the clamping gap 100c. This is particularly clear in the side view of FIG. 4c . The diameter d of the cylindrical guide channel 31 is illustrated there. The front cylindrical portion of the band hopper insert 30 has two laterally tapering surface sections 31a, 31b which have the curvature shown in FIG. 4a . Corresponding to the tapering band funnel insert 30 and the cylindrical bore 31 which has the same diameter, a V-shaped opening end results from which the flowing air of the injector bores emerges, with which the fleece is conveyed to the clamping gap.

Due to the width b of the calender disks in relation to the significantly smaller diameter d of the cylinder guide channel, the air can escape from the side only poorly or slowly, so that the main part of the flowing air is guided to the nip and deposits the fleece of fibers that it has brought with it.

A top view is shown in FIG. 4b , in which the width of the two calender disks 100a, 100b can be seen. Also recognizable are the injector bores 64a, 64b as feed channels to the ring channel 33, and the parallel offset inclined injector channels 34a, 34b in use 30. There are at least 2 injector channels so that the sliver is centered and at the same time receives a twist.

4 bar can be mentioned as an example of a compressed air to be used, but is tuned to a duct diameter of approximately 3.8 mm in the belt funnel and approximately 8 mm in the insert 40 of the fleece funnel 50. Attempts have shown that compressed air of approx. 500 m / sec. It is sufficient to safely insert the front part F1 of the sliver up to the clamping gap 100c. The length H1 of the manually narrowed fiber fleece is matched to the distance from the fleece funnel 50 to the clamping gap 100c and thus the length of the airtight fiber sliver channel.

In an alternative variant (not shown in the drawing), the ring channel 33 mentioned can also be formed on the insert 30, for example by a circumferential notch.

FIG. 5a shows a fleece funnel 50 with a nozzle insert 40 '. The insert 40 'is designed in one piece. The insert 40 'has its sliver guide designed so that the sliver guide corresponds to the sliver guide of an insert 40 in a first section and corresponds to the sliver guide of a sliver funnel 30 (according to FIG. 4a) in a subsequent section. According to FIG. 5a, such an insert 40 'is in the processing position, ie a position for placing the nonwoven in the funnel area 50a. The insert 40 'also assumes this position according to FIG. 5a if the fiber fleece has jammed.

An exchange of the insert 40 'is much faster than an exchange of the insert 40 and the band funnel 30 according to FIG. 1. Readjustment or adjustment work can be omitted due to the compact (one-piece) shape of the insert 40'. There is also no longer any need for an airtight, pivotable joint.

In an advantageous embodiment, a calender disk 100b and the insert 40 'are arranged in a common support means or holder (not shown). The suspension element is pivotally mounted about a pivot point SP. The calender disk 100b and insert 40 'can be pivoted about the common pivot point SP. Since the insert 40 'is connected to the fleece funnel 50, both are consequently pivoted. For reasons of simplicity, however, only the pivoting of the insert 40 'is referred to below. It is achieved with the pivoting that the operator has better accessibility and insight into the use 40 '. Conveyed nonwoven fabric can thus be manually placed in the funnel area 50a to thread the beginning of the nonwoven fabric. The nonwoven fabric is formed into a fiber band with the nonwoven funnel and is immediately guided between the opened calender disks 100a and 100b. For the start of stationary operation, the insert 40 'and the calender disk 100b are pivoted back into the position according to FIG. 5b. This corresponds to the position for stationary operation (working position) of the insert 40 '.

Another embodiment enables the insert 40 'to be pivoted separately and the calender disk 100b to be pivoted separately about the pivot point SP. This ensures that the calender disk 100b can remain in the closed position while the tape is being inserted. Only the insert 40 'can be pivoted to insert the beginning of the tape. If it is necessary to open the calender disks, this can be done separately.

An embodiment is also conceivable in which the insert 40 'is not arranged to be pivotable, but rather is arranged in a stationary manner, corresponding to FIG. 5b. In such an embodiment, the guide surface LF of the fleece funnel 50 must be designed to be pivotable. A pivot axis must expediently be arranged in the lower region of the guide surface, so that the guide surface LF can only be pivoted away from the funnel region 50a. If the nonwoven is jammed, this enables the guide surface LF to pivot away, so that the nonwoven can escape from the funnel area 50a. Furthermore, with the pivoting of the guide surface LF, the operator can see into the funnel area 50a. In this embodiment, a calender disk 100b can also be pivoted separately to a pivot point SP.

Claims (13)

Method for inserting at least one non-woven fabric part in front of the clamping line (100c) of compacting calender disks (100a, 100b) of a textile machine processing sliver, in which
an air flow is conducted without loss through at least two nozzle sections (30, 60, 40) of the sliver guide up to directly in front of the clamping gap (100c) of the calender discs (100a, 100b) in order to initially guide this part (F1) of the nonwoven fabric (F) into a guide device ( 50, 40, 60, 30) automatically (without mechanical insertion aids) and placed directly in front of the clamping gap (100c). Method according to Claim 1, in which flowing air escapes directly at the clamping gap (100c) transversely to the sliver conveying direction. Method according to one of the mentioned claims, in which the clamping gap (100c) for the passage of guide air is slightly to clearly opened, in particular by moving one of the calender disks (100b) relative to the other (100c) calender disk. Method according to one of the mentioned claims, in which the width (b) of the calender disks (100a, 100b) parallel to their axis of rotation is significantly, in particular two to three times, wider than the diameter of the nozzle section (31) immediately in front of the clamping gap (100c) the sliver guide is. Band funnel (30) in a sliver guide without a longer collecting or guide tube (8) for carrying out the method according to one of the preceding claims, in which a) the band funnel has a guide channel (31, 32) which tapers in a conical shape (32) to a cylindrical front section (31); b) in the cylindrical section (31) a plurality of injector bores (34a, 34b) are provided, which are inclined in the sliver conveying direction; c) the cylindrical front portion (31) ends in a pointed end (36) of the band funnel (30); characterized in that d) the diameter (d) of the cylindrical front section (31) is substantially smaller than the width (b) of the calender disks (100a, 100b) and the guide channel (31, 32) is designed without lateral ventilation openings. Sliver funnel with sliver guide according to claim 5, wherein the diameter (d) is less than a third of the width (b) of the calender disks. A sliver funnel with a sliver guide according to claim 5 or 6, in which the pointed end (36) is linear and surface sections (31a, 31b) open into the line from two sides, the curvature of which corresponds to the curvature of the surface of the calender disks (100a, 100b). Belt funnel with fiber band guide according to one of claims 5 to 7, in which no lateral ventilation is provided between the fleece funnel (50) and injector bores (34a, 34b). Belt funnel with fiber band guide according to one of claims 5 to 8, in which a laterally airtight joint (35) is provided above the conical section (32), around which the fleece nozzle (50) can be pivoted relative to the belt funnel (30). A sliver funnel with a sliver guide according to one of claims 5 to 9, in which the pointed, linear end (36) of the sliver funnel has approximately the width of the clamping gap (100c) of the calender disks. A sliver funnel with a sliver guide according to one of claims 5 to 10, wherein the sliver funnel insert (30) has at least two injector channels (34a, 34b) which are inclined to the direction of the carriage of the sliver and whose mouth is opposite in the cylindrical bore (31), but are staggered in parallel. Fleece funnel (50) with a nozzle insert for carrying out the method according to one of the preceding claims, wherein the nozzle insert (40 ') with a calender disc (100b) is arranged on a common support means, so that the nozzle insert (40' ) and the calender disk (100b) can be pivoted about a common pivot point (SP) by means of a support means. Fleece funnel (50) with a nozzle insert for carrying out the method according to one of the preceding claims, wherein the guide surface (LF) of the fleece funnel is pivotable and the nozzle insert (40 ') is fixed with respect to its position in relation to the calender discs (100a, 100b ).

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