Title of Invention

AN APPARATUS FOR GUIDING A FIBRE WEB

Abstract

(57) Abstract: The present invention concerns an apparatus for guiding a fibre wet) (VI, V2) on a guide surface (20) of a guide element (4) extending transversely with respect to thedirection of transport (T) of the fibre web. The devices known thus far are not adjustable or provide inadequate adjustability merely. For effecting optimum adaptation of the fibre web widths (B) a guide element (4) is proposed which is designed deformable Into an arched shape, extending in a plane (30) arranged transversely with respect to the direction of transport (T) of the fibre web (V+, V2). and maintained in its set position by means of a holding device (10). PRICE: THIRTY RUPEES

Full Text

The present invention concerns an apparatus for guiding a fibre web on a guide surface of a guide element extending transversely with respect to the transporting direction of the web. In the European Patent EP-PS 139 236 web guides are shown in the Figures 8 each provided with a different cross-section. Thus e.g. in Fig. 8c an arched web guide 5.3 is shown, owing to the bulging arch of which the width of the web sup¬plied from the drafting system 4 is increased. Depending on the requirements of the application, particularly concerning a desired width of the web, a correspond¬ingly shaped web guide is applied. Particularly in setting a machine of this type, in which fibre webs are supplied by a plurality of supply points onto a transporting table and which subsequently are doubled, exact setting of the web widths is indispensable. The settings are to en¬sure that on one hand the webs to be doubled are superimposed exactly and that on the other hand formation of lanes in the fibre web, due to the still partially pre¬vailing fibre sliver structure, is avoided. Lane formation means that over the width of the web void zones form, continuous fibre distribution over the width of the fi¬bre web no longer being ensured. Such lane formation adversely affects subse¬quent processing. Setting the width of the web also is important in view of the subsequent processing unit, in which a defined web width of the supply fibre ma¬terial is desired. This indicates that exact setting of the web width is of crucial importance if a high quality end product (yarn) is to be produced. The settings must be adjusted every time any changes in processing (e.g. change of the material processed) are ef¬fected. This implies that in the apparatus proposed in EP-PS 139 236 depending on the settings desired an exchange of the web guides shown Is to be performed. Several exchanges might be required before the desired result is obtained. This results in a considerable work effort as well as in the necessity to keep many web guides of different cross-sectional structures in stock. Furthermore in the also known Japanese utility model JP-U-6-47 368 an adjust¬ing device can be seen, in which the inclination of lateral guide surfaces of a guide plate can be adjusted. This device, however, merely influences the outer¬most rim zones on each side of the fibre web. Homogeneous setting across the whole width of the web, particularly for preventing the lane formation mentioned, can not be achieved using this arrangement. Furthermore the web guide con¬cerned is approximately concave, using which as a rule narrowing of the web width can be achieved. An increase of the fibre web width which is supplied by a preceding element (e.g. a drafting system) thus can not be achieved using this device. It thus is the goal of the present invention to create a guide element for a fibre web in such a manner that on one hand the disadvantages of the state of the art described are avoided and that on the other hand a simple and optimal adapta¬tion of the fibre web width is ensured. Additionally special lateral web guides, as shown e.g. in said Japanese utility model are to be dispensed with. This goal is achieved in that the guide element is laid out in a plane extending transversely with respect to the transporting direction of the fibre web as a deformable arch-shaped element which is held in its set position using a holding device. Owing to this arrangement it becomes possible to effect adjustments in a simple manner depending on the supply material to be processed. It is proposed that the guide element preferentially is made from an elastic mate¬rial. This in particular permits simple design of the holding device supporting the guide element and e.g. a design, as proposed in the following, provided with a simple continuously variable adjusting device. Owing to the elasticity of tfie guide element it becomes possible to design the ad¬justing devices in such a manner that, for setting the bending radius of the guide element, the adjustment is effected by applying a pressure force acting onto the end portions of the guide element. Owing to the design, also proposed, of (he cross-sectionaf structure of the guide element no further elements are required for laterally guiding the guide element additionally in the direction of transport. The cross-section of the guide element is designed in such a manner that the bending stiffness in the direction of fibre web transport exceeds the one in the plane extending transversely with respect to the direction of transport of the fibre web. For preventing in particular any crossing of the guide element it is proposed to provide the guide element in both its end portions with guide elements protruding into guides of the holding devices. Said guide elements can be designed as pins, studs, bolts or similar elements to be inserted into to elongated slot-like bores in the holding elements and to be guided therein. Preferentially the adjusting elements for setting the guide elements are arranged in the holding devices in such a manner that they exert a pressure force acting onto the end portions of the guide elements as an adjustment Is effected. For maintaining a chosen setting it is proposed that the setting elements are de¬signed as locking thread bolts. Preferentially the guide element is made from a synthetic material. It also could be imagined, in this connection, to have the guide element made from a compos¬ite material or from a combination of materials respectively. The material is to be chosen strictly according to the predetermined elastic deformability required for achieving the arched shape of the guide element. Accordingly, the present invention provides an apparatus for guiding a fibre web on a guide surface of a guide element extending transversely with respect to the direction of transport of the fibre web, characterised in that the guide element is designed as an element extending in a plane arranged transvereely with respect to the direction of transport of the fibre web and as an element which can be deformed in arch-shaped form and is maintained in its set position via a holding device. Further characteristics are described in the following with reference to illustrated design examples. It is shown in: Fig. 1 a schematic top view of an arrangement provided with the inventive guide elements, Fig. 2 a schematic front view of a design example of the guide element, Fig. 3 an enlarged view of the holding device according to Fig. 2 (The guide ele¬ment being shown in its relaxed or not tensioned state). Fig. 4 a top view of the arrangement according to Fig. 3, Fig. 5 a further design example of a guide element, Fig. 6 a cross-section along the line A-A according to Fig. 5. In Fig. 1 a partial view is shown of a lap forming machine 1 e.g. of the type shown and described in more detail in our earlier Swiss Patent Application CH-1335/94. A feed table is designated by the reference number 2, on which the doubled web V is fed to lap forming device for formation of a fibre layer lap. The doubled web V is composed of the individual fibre webs VI and V2 supplied each by the drafting system units S1 and S2. Before the fibre webs V1 and V2 are supplied to the feed table 2 they are guided each across a guide element 4. The supply of fibre slivers to the drafting system units S1 and S2 is not shown and can be explained e.g. with reference to the aforementioned Swiss Patent Application. In Fig. 2 a guide element of this type is shown in more detail in a front view, i.e. seen in the transport direction T of the fibre web V. In this arrangement the guide ■ element is formed as an elastic rod 5 which in its end portions El and E2 is pro¬vided with reinforcements 6. In the end portions mentioned a pin 7 each is pro¬vided in the zones of the reinforcements 6 each of which at either side engages an elongated slot-like bore 8 provided in a holding device 10. The holding device is shown in more detail in the Figures 3 and 4. The holding device 10 on either side is provided with a lateral extension 11 each, in which the elongated bores 8 or slots are provided. The pins 7 in this arrangement on either side penetrate through the extensions 11 via the elongated bores 8. Additionally the holding device 10 is provided with a traverse member 13 which on one hand inter¬connects the two extensions 11 and on the other hand takes up a nut 15. The nut 15 in this arrangement is rigidly connected with the traverse member 13. The tra¬verse member 13 furthermore is provided with a through bore 16 located con¬centric with the nut 15, through which a threaded stud 18 protrudes each screw¬ed into a corresponding nut 16 each. As already mentioned the guide rod 5 with its guide surface 20 is shown in Fig. 3 in its relaxed state i.e. extending straight. For transformation into the arched form, shown e.g. in Fig. 2, the threaded studs 18 by rotation are moved towards the centre which causes the pins 7, against which the end threaded stu In Fig. 5 a further embodiment of a guide element 4 is shown the guide element itself consisting of a shaft 22 (made e.g. from a synthetic material) which in its bending portion 24 is provided with a flattened zone 25. The cross-section of this flattened zone is visible in particular in the sectional view shown in Fig. 6. This flattened zone ensures that, if a pressure force is applied acting onto the sche¬matically shown pins 7, the shaft 22 deflects in transverse direction with respect to the fibre web VI guided thereon. This means that in this arrangement the bending stiffness in the direction transverse with respect to the direction of trans¬port of the fibre web VI is lower than the one prevailing in the transport direction. Settings are effected via the holding elements in the same manner or in a similar manner as described with reference to the design example shown in Fig. 3, and Fig. 4 respectively. In order to prevent any loosening of the settings during operation additional counter-nuts could be provided in the zone of the threaded studs acting onto the nuts 15. Also the adjusting device could be designed in such a manner that adjustment of the guide element 4 can be effected only from one side of the machine, i.e. in the zone of one end portion El, or E2 respectively, only. There is a wide variety of possible design solutions for embodiments of the adjusting device. The term "web" is not to be interpreted restrictively. On the contrary the inventive apparatus also can be applied also as a guide for fibre mats. WE CLAIM: 1. An apparatus for guiding a fibre web (VI, V2) on a guide surface (20) of a guide element (4) extending transversely with respect to the direction of transport (T) of the fibre web, characterised in that the guide element (4) is designed as an element extending in a plane (30) arranged transversely with respect to the direction of transport (T) of the fibre web (VI, V2) and as an element which can be deformed in arch-shaped form and is maintained in its set position via a holding device (10). 2. The apparatus as claimed in claim 1, wherein the guide element (4) at least in its portion of the bending zone is made fi'om an elastically deformable material. 3. The apparatus as claimed in claims 1 or 2, wherein the holding device (10) is provided with a continuously variable adjusting device (15, 18). 4. The apparatus as claimed in claims 2 or 3, wherein the adjusting device comprises adjusting elements (15, 18) exerting a pressure force, acting transversely with respect to the direction of transport (T) of the fibre web, onto the end portions (El, E2) of the guide element. 5. The apparatus as claimed in any one of the claims 1 to 4, wherein the cross- section of the guide element (4) is designed in such a manner that, if a pressure force is exerted acting on the end portions (El, E2) of the guide element, the arch-shape deformation occurs only in the plane (30) extending trans\'erse]y with respect to the direction of transport (T) of the fibre web (VI, V2). 6. The apparatus as claimed in any one of the claim 1 to 5, wherein the guide element (4) in the zones of both its end portions (El, E2) is provided with guide elements protruding into guides provided in the holding device (10). 7. The apparatus as claimed in claim 6, wherein the guide element (7) are designed as pins or bolts guided in the elongated slot-like bores (8) in the holding device (10). 8. The apparatus as claimed in claims 6 or 7, wherein the holding devices (10) are provided with setting elements (18) exerting a pressure force (K) acting onto the end portions (El, E2) of the guide elements (4). 9. The apparatus as claimed in claim 8, wherein the setting elements are designed as threaded studs (J 8) which can be locked. 10. The apparatus as claimed in any one of the claims 1 to 9, wherein the guide element (4) is made from synthetic material. 11. An apparatus for guiding a fibre web, substantially as herein described with reference to the accompanying drawings.

Documents:

1010-mas-1996 abstract.pdf

1010-mas-1996 claims.pdf

1010-mas-1996 correspondence-others.pdf

1010-mas-1996 correspondence-po.pdf

1010-mas-1996 description (complete).pdf

1010-mas-1996 drawings.pdf

1010-mas-1996 from-2.pdf

1010-mas-1996 from-26.pdf

1010-mas-1996 from-4.pdf

1010-mas-1996 from-6.pdf

1010-mas-1996 others.pdf

1010-mas-1996 petition.pdf