Drum carding machine for making non woven fabrics and natural or synthetic fiber webs

Abstract: A carding machine comprises either a single carding unit or multiple carding units, for making non woven fiber laps and natural or synthetic fiber webs, each carding unit including a first carding drum (T1) and a conveyor cylinder (TR) cooperating with the first carding drum, as well as a second carding drum (T2), between the first and second carding drums there being arranged, after the conveyor cylinder, two or more combing cylinders (P1,P2) for conveying the half-finished fiber web to the second carding drum as the carding machine comprises multiple carding units (Fig.1); or, as the carding machine comprises a single carding unit, each combing cylinder, supplied by a single conveyor cylinder (TR), is followed by a distributor cylinder (S1) cooperating with a further cylinder for removing the carded webs or laps (Fig. 2); or, as the carding machine includes multiple carding units, each drum is followed by a conveyor cylinder (TR) supplying two or more combing cylinders (Fig. 3) (P1,P2); the carding drum comprising several operating assemblies for evenly spreading the fibers on the drums.

Description: The present invention relates to a carding machine including either a single carding unit or a plurality of carding units, in particular for making non woven fiber laps or fabrics (which are also called non-wovens), and open-end laps or articles. The carding machine of the above mentioned type usually comprises one or more carding units,and each carding unit includes at least a first, a second and also a third region: the first region is provided for supplying and roughing the fiber material, the second region, called carding unit proper which can be a multiple unit in carding machines having several assemblies, being provided for refining the processed material so as to evenly spread the fibers and discharging them on one or more combing cylinders, the third region being provided for forming the carded laps and removing the latter from the end cylinders of the machine. A carding machine according to the preamble of claim 1 is known from EP-A-0 188 177. In particular, the present invention relates to a carding machine including fixed and movable carding drums and cylinders or caps, as well as combing cylinders, with at least a first supplying region, an intermediate processing region and a discharging or output region, which operate as follows: the first supplying region comprises an unit for supplying the natural or synthetic fibers in a staple condition, for subjecting the staple fibers to an opening step before supplying the fibers to the subsequent region; the second intermediate processing region comprises a first carding drum and processing cylinders as well as turning cylinders and/or fixed or movable carding caps arranged on the periphery of the drum to separate, unravel,orient and card the fibers by means of a carding step proper; this region further comprising a converyor cylinder which turns with a turning speed which is 25-80% greater than the speed of the carding drum, followed by two combing cylinders, the second region including a plurality of like regions in the carding machine having several carding units; the third region comprises condensing members and/ or discharging members including web or flap removing cylinders or combs which are supplied by output combing means. The web from the first carding drum is removed by means of the conveyor cylinder which has a double function of: a) a conveyor cylinder,since it has a turning rate of 25-80% greater than the rate of the carding drum, and being provided with a carding clothing including teeth adapted to entrain and remove all of the fibers supplied by the first carding drum; b) a discharging cylinder or drum which discharges the fibers loaded thereon in part on a first combing unit and in part on a second combing unit. The fiber material which is present on the two combing units is directly discharged on the second carding drum of the mentioned carding machine, since the speed of this second drum is much greater than that of the two combing units. The rotary direction of the two combing units can be either clockwise or anti-clockwise. For removing the fiber material from the conveyor cylinder it is possible to use two or more combing units. By these combing units or cylinders, there is obtained a carded fiber web having two layers on the second drum of the carding assembly. The main advantages of the carding machine of the present invention are hereinbelow listed: 1) The fiber material is fully removed or discharged from the first carding drum; 2) A better mixing of the fibers carded by the first drum before discharging said fibers on the second carding drum, owing to the provision of a plurality of turning and processing cylinders; 3) A facilitated discharging operation from the conveyor cylinder since the latter has a less diameter and a greater speed than the first drum; 4) The carding drum can rotate with a peripherical speed less than the speed of prior carding drums, without impairing the fiber discharging operation while reducing or fully eliminating the fiber wirls on the surface of the first carding drum, as well as possible meltings of thermoplastic fibers; 5) On the first carding drum it is possible to use carding clothings with sharper angles so as to greatly increase the carding power of the machine, since the discharging from the first drum is independent from the combing units and is set by the conveyor unit arranged after the first drum, so as to omit the prior art combing and conveyor cylinders to greatly simplify the construction of the carding machine; 6) A better exploitation of the surface of the first carding drum is possible, since it is possible to recover a space on its periphery and thus add a greater number of operating and turning cylinders or other carding members, so as to greatly improve the distribution of the fibers on the drum. This solution can be applied, as discovered by the Applicant, both in the first carding assembly or unit and in the end carding unit of any carding machine. Moreover, if the invention as disclosed is applied to the end carding unit or assembly, it allows to use a single distributor cylinder for each combing cylinder, whereas there are at present necessary two distributor cylinders in order to obtain two separated and condensed flaps. A main feature of the invention, accordingly, is the provision of a conveyor cylinder and two or more combing cylinders arranged between the two drums of each carding unit or assembly, which thing allows to reduce the required space on the periphery of the main drum and accordingly it allows to add several working or operating and turning cylinders or other fixed or movable carding members on the drum, thereby improving the arrangement of the fibers and increasing the yield of the machine both from a qualitative and a quantitative standpoint, since the lap produced by the carding machine comprises two layers having a homogeneity and resistance greater than those of a lap or web consisting of a single layer, the specific weight of the fiber structure being the same. The possibility of superimposing two separated layers by using two combing units allows to obtain a lap or web of greater specific weight. Accordingly, the main object of the invention is to improve the yield and quality of the lap or web produced by the carding machine, as well as to simplify its construction which, as stated, is at present very complex. According to the invention, this object is achieved owing to the fact that the above mentioned means for removing the fiber lap or web from the carding drum comprise a conveyor cylinder followed by two intermediate combing cylinders for forming two parallel laps, which operate to deposit a two-layer lap on the second carding drum. This feature allows to enhance the advantages bound to the provision of two or more output combing cylinders, since the provision of a conveyor cylinder connected to two intermediate combing cylinders allows the second drum to be supplied with a greater amount of fibers, thereby improving the carding machine yield and providing an improved product quality with respect to the homogeneity and strength or resistance of the obtained lap or web. Preferably, the first drum is covered by a carding clothing having teeth which have a slope greater than that of conventional carding teeth, and with the tips of the teeth facing the rotary direction of the drum, which coincides with that of the fiber material advancement. The conveyor cylinder is covered by a carding clothing in which the tips of the clothing teeth face, as stated, the rotary direction. The two intermediate combing units or assemblies are suitably covered by carding clothings having an angle which is greater than that of the drum and with tips facing a direction adapted to retain the fibers supplied by the conveyor. Moreover, the conveyor cylinder and the two combing cylinders are provided with carding clothings having angles of different density and they may also have peripheral different speeds; moreover, the turning direction of the combing units or assemblies does not affect the yield. The conveyor cylinder is provided with carding clothings including teeth the tips of which face the advancement direction of the fiber materials so as to remove the fiber product from the main drum by means of a sort of drawing effect because of the speed greater than that of the carding main drum, which thing allows a less strong construction, so as to reduce the inertial effects of the drum, with a consequent less requirement with respect to the starting power. Then, the two combing cylinders transfer the lap or web formed by the conveyor cylinder to the second drum of the end region, thereby holding the characteristics of said lap constant. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be disclosed in a more detailed way hereinafter with respect to a not limitative embodiment thereof, with reference to the companying drawings, where: Figure 1 is a schematic diagram illustrating a carding machine including a double carding assembly of the first carding machine stage, including drums and cylinders according to the ivnention, the second stage being shown as a conventional system; Figure 2 illustrates an end stage according to the invention of the simple carding unit carding machine; and Figure 3 illustrates a double carding assembly or unit carding machine, in which the two carding units are made according to the invention. DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in Figure 1, the carding machine comprises a first region, generally indicated at A, two second regions indicated at B1 and B2, and the third region generally indicated at C. The region A comprises a continuous belt supplying conveyor NT1 for supplying staple fibers to inlet members including the cylinders 1 and 2, the cylinder 1 being provided with a tray member for collecting the fibers in order to allow the latter to be engaged by the cylinder 1. The cylinder 2 is a loader which transfers the fibers from the cylinder 1 to the carding drum T1 of the region B1. The region B1, as shown, comprise a cylinder-drum T1, and on the periphery of the drum T1 there are provided several operating or working cylinders L as well as several associated turning cylinders V. The rotary directions of the cylinders L, V and drum T1 are indicated by arrows. Preferably, the drum T1 is covered by a toothed carding clothing the teeth of which have a slope that is greater than that of conventional carding teeth, so as to improve the carding power of the machine, the subject teeth having their tips facing the turning or rotary direction, which coincides with that of the fiber material advancement. The region B further comprises a conveyor cylinder TR cooperating with two inner combing cylinders or units P1, P2. The removal of the fiber material from the drum T1 is performed exclusively by the cylinder conveyor TR which turns with a speed which is of 25-80% greater than that of the drum T1. Said conveyor cylinder TR contacts the two combing cylinders P1 and P2 which are covered by carding clothings including teeth with a high angular value, and the rotary direction of which is unimportant. In this connection it should be pointed out that the two intermediate combing cylinders P1, P2 can be coated by carding clothings having either like or different angle and density values, and they can also have either like or different peripheral speeds. The two cylinders P1 and P2 operate as transfer members for transferring the fiber material from the region A to the region C, and the tips of the teeth of their carding clothings face the rotary direction indicated by the arrows and have a peripheral speed which is less than that of the intermediate conveyor cylinder TR. The material removal effect provided by the conveyor cylinder TR on the drum T1 is performed through a drawing effect, whereas between the conveyor cylinder TR and combing cylinders P1, P2 it is obtained by means of a condensation of the fibers. As shown, the region B2 comprises a second carding unit or assembly including a drum T2 and two output combing cylinders P3, P4 which turn in the direction indicated by the respective arrows. The region C comprises the discharging zone of the combing cylinders P3, P4: in the embodiment being disclosed it comprises for each combing cylinder a double condensing cylinder S3, S4 and a related unloading assembly including the cylinder S5 and a conveyor belt NT2 conveying the lap to the subsequent carding machine. As stated, the regions A, B1, B2, C form a two carding drum carding machine, in which the section A is provided for supplying and roughing the fiber material, the section or region B1 for performing a first carding operation on the fibers and for the conveyance thereof, the region or section B2 for refining the openings between the fibers and forming evenly carded laps, and, finally,the region or section C operates to unload and discharge the lap or web. The disclosed carding machine operates as follows: The two intermediate combing cylinders P1 and P2 condense on their surfaces the fibers supplied by the drum T1 through the conveyor cylinder TR, so as to form two separated laps. The two laps formed on P1 and P2 are directly sent to the second drum T2 of the region B2. The latter is thus supplied with a greater material amount, so as to improve the yield and the quality of the lap with respect to prior carding methods. In fact, by removing the fiber material from the drum T1 by the conveyor cylinder TR and the two intermediate combing cylinders P1 and P2, the drum T2 can be perfectly supplied with fibers, since the supplied fibers are separated on two different paths. Thus, it is possible to provide, just in the first section of the carding machine, a lap of great homogeneity, even by starting from staple fibers of very different characteristics, that is having different quality, density and length. On the other hand, the greater yield which can be obtained by using a conveyor cylinder TR and two intermediate combing cylinders P1, P2 allows to use carding clothings including teeth with a less pitch, and accordingly provided with a greater carding power just in the region B1, so as to further improve the quality of the obtained product. The provision of the two intermediate combing cylinders P1, P2 allows either like or different peripheral speeds and either like or different rotary directions so as to allow the fibers to be indifferently arranged on the surfaces of the combing cylinders, thereby improving the eveness of the laps. These advantages add to those obtained owing to the provision of an outlet conveyor cylinder, and, because of this feature, the carding machine according to the present invention, greatly improves the end product. Figure 2 illustrates and end stage of the carding machine which, after each combing cylinder P1, P2,comprises a distributor cylinder S1 for each combing cylinder P1 and P2, each of said cylinders S1 being followed by a second removing cylinder S2 which detach the lap, the two separated laps being then sent to an end compression assembly. Figure 2 illustrates the two carding assemblies, in which each drum is followed by a conveyor cylinder TR supplying two combing cylinders P1, P2; moreover, each combing cylinder P1 and P2 of the end region C includes a distributor cylinder S1 followed by the unloading cylinder S2. While the invention has been disclosed and illustrated with reference to a preferred embodiment thereof, it should be apparent that the disclosed embodiment is susceptible to several modifications and variations all of which will come within the spirit and scope of the appended claims.

Claims: A cylinder carding machine, for making non-woven webs and laps, half-combed fiber webs and open end fiber webs, said carding machine comprising sequentially a first fiber supplying region (A), a second and third intermediate regions (B1, B2) and an end output region (C), said first fiber supplying region comprising a conveyor belt (NT1) and two loading cylinders (1, 2) for supplying natural or synthetic fiber to be carded, in staple form, to a first carding drum (T1); said second region (B1) comprising said first carding drum (T1) and a plurality of processing and turning cylinders (V, L) and/or fixed or movable carding members, arranged on a periphery of said first carding drum (T1) and adapted to separate, unravel and orient or card said fibers so as to provide a first carding operation; said second region also comprising a conveyor cylinder (TR) followed by two combing and discharging cylinders (P1, P2); said third region (B2) comprising a second carding drum (T2) supplied by said conveyor cylinder (TR) and said two combing and discharging cylinders (P1, P2 ), a plurality of processing and turning cylinders (V, L) arranged on a peripheral portion of said second carding drum, and further including one or more combing cylinder (P3) arranged at the outlet of said second carding drum (T2) and cooperating with said second carding drum (T2); said end output region (C) comprising discharging cylinders (S3, S4, S5) supplied by said second carding drum (T2), said carding machine being characterized in that said conveyor cylinder (TR) has a peripheral speed which is of 25-80% greater than the peripheral speed of said first carding drum (T1), cooperates with said first carding drum (T1) and said two combing and discharging cylinders (P1, P2) so as to discharge the fibers loaded on said conveyor cylinder (TR) in part on one of said two combing and discharging cylinders (P1) and in part on the other of said two combing and discharging cylinders (P2) said conveyor cylinder (TR) being covered by a carding clothing having teeth for entraining fibres supplied by said first carding drum. A carding machine according to Claim 1, characterized in that said conveyor cylinder (TR) and said two combing and discharging cylinders (P1, P2) are so arranged as to provide to said second carding drum a fiber lap comprising two homogeneous substantially parallel layers. A carding machine according to Claim 1, characterized in that said two combing and discharging cylinders (P1, P2) are covered by carding clothings of a high angular value and including teeth having tips facing either the rotary direction or an opposite direction thereof, whereas the conveyor cylinder (TR) includes carding teeth having tips directed in the advancement direction of said fibers. A carding machine according to Claim 1, characterized in that the two combing and discharging cylinders (P1, P2) are driven with different or equal rotary speeds, either different or equal to that of the conveyor cylinder (TR), and with mutually equal or different turning directions. A carding machine according to Claim 1, characterized in that said end output region comprises after said second carding drum (T2) a further conveyor cylinder (TR) and one or more of said combing cylinders (P1, P2), each of said combing cylinder being followed by a single condensing cylinder (S1) including fiber lap unloading means (S2) for unloading the fiber lap directly into a store or to another carding machine.

Inventors: NAPOLITANO NICOLA, NAPOLITANO, NICOLA
Applicants: TECNOTEX BIELLA S R L, TECNOTEX BIELLA S.R.L.
Application year: 1992
Main classification: D01G15
IPC codes: D01G15