Card for cotton and for similar uses, with fixed carding flats which form cleaning members

Abstract: A card comprising fixed carding flats, wherein at least those ends of the components (12) of the flats turned toward the arriving clothing (7) of the cylinder (5) are given an acute angle, thus functioning as cleaning members for the removal of the impurities, assisted in this by suction pipes (16).

Description: The operation of carding consists essentially in separating the discontinuous fibers, at the same time freeing them from the impurities still present and completing in this manner the opening and the cleaning initiated in the preceding operations. In cards with flats, the carding action is carried out mainly between the main.cylinder which rotates at high speed and a series of rotating flats or a series of fixed flats. The main cylinder and the flats - both those in movement and those which are fixed - are covered with a close-packed rigid clothing formed from steel teeth which are opposed between the teeth of the main cylinder and the teeth of the flats. The rubbing between the teeth creates the carding. The cards with flats serve to create a band by parallelizing the fibers and removing the impurities of the same. The flats rotating with the carding action cyclically bring the clothings to the outside, above the carding cylinder; on the way out, said clothings are cleaned by a blade in movement. Unfortunately, these flats remove only some impurities and not all, but also remove fibers of a suitable length for creation of the thread, thus discarding and losing fibers also which would be useable for spinning. In the solution with fixed flats, the same only card and do not remove impurities. To remove the impurities, additional inclined blades have until today been applied at various points of the main carding cylinder, increasing the expenditure for the construction of the cards and for maintenance, and limited cleaning is obtained, given the small number of cleaning blades. From EP-A-0310964 there is known a card for cotton and for other uses, comprising fixed carding flats, wherein at least those ends of the components of the flats turned toward the arriving clothing of the cylinder are provided with transverse inclined blades shaped at an acute angle functioning as cleaning members for the removal of the impurities. In EP-A-0144607 serrated cutting blades and distance blades are provided, these last ones are interposed between said cutting blades. With the present invention, the carding and the cleaning of the fiber is simplified, with adoption of carding flats of fixed type. With the present invention, moreover, better parallelization of the fibers, better cleanness, lower loss of fibers, avoiding having useful fibers discarded, and greater production which varies from 20% to 70% are obtained. The present invention also makes possible the adoption of a suction or other special air circulation, with which the heating of the material and the consequent softening of certain impurities and the negative consequences on the functioning of the card are avoided. Starting from EP-A-0310964, the above advantages are obtained with the features of the characterizing portion of Claim 1. Clothings with teeth of the existing types can be used equally well. According to a known technique, the fixed flats are formed by blades and by distance pieces interposed between the blades; in this case, the ends of the blades and of the distance pieces are given an acute angle. In this case, according to a possible embodiment, the front ends of the distance pieces can be extended also to come side by side with the ends of the blades formed at an acute angle, and are shaped like those ends of the blades. In any case, an inclined transverse cleaning blade is constituted. In its oblique form, the flat can therefore have a comb-like or smooth form; comb-like serves for cleaning even the most microscopic impurities in the entire circumference of the fiber; the smooth form (blade type) serves for cleaning normal impurities. This flat without any further application becomes a flat cleaning the impurities of the fiber. In a card, therefore, there is provision to apply various flats and each flat has its oblique form cleaning the impurities of the fibers; all carding points are thus also cleaning points. The acute-angled ends can have an angular size of approximately 45°. The opposite ends also of the components of the flats can be at an acute angle, increasing the discharge spaces between adjacent flats. In the spaces between adjacent flats, channels parallel to the flats and open toward the clothing of the cylinder can be formed, and means are provided for creating pneumatic currents for suction of the impurities separated by said shaped ends. By having both the ends of the blades of the various adjacent flats shaped at an acute angle, there are created between adjacent flats interspaces with ample opening in the centrifugal direction for discharge of the impurities, for the arrangement of any channels for pneumatic suction currents, and also for making it possible to define a hollow space for circulation of fluid for cooling the flats, for the purposes indicated above. The width of the interspace is adjusted according to the length of the fiber, of the impurities and of the short fibers which it is desired to eliminate in working. The suction of the impurities also makes it possible to cool the flats, making the same stay at a constant temperature. In short, the possibility of better carding, of better cleanness and of less breakage of fibers is obtained, and consequently also a very regular band and a substantial increase in production, with minimum loss of useful fibers. The invention will be better understood by following the description and the attached drawing which shows a non-limiting practical illustrative embodiment of the invention itself. In the drawing Fig. 1 shows a general simplified diagram of a card; Fig. 2 shows in cross-section a part of the cylinder of the clothing with its flats made according to the invention; Figs 3 and 4 show an enlarged detail of the ends of two adjacent flats and a view from the line IV-IV in Fig. 3, and Figs 5 and 6 are similar to Figs 3 and 4 but show a solution which is modified as compared to Figs 3 and 4 themselves. According to Fig. 1, F1 indicates the feed of the material which is supplied from the cylinder 3 to the cylinder 5 which rotates in the direction of the arrow f5 and which has a carding clothing indicated by 7 and more clearly visible in Fig. 2. 9 indicates the fixed flats which are made according to the invention but with the known technique which provides for the formation of the active components of the flats with series of alternate blades and distance pieces, as is shown in particular in Figs 3 to 5. Engaged alternately on support structures 9A, by means of suitable outlines and fixing means, are both distance pieces 10 and shaped blades 12 with the points which are to interact with the clothing 7. According to what is illustrated in the drawing, the ends of the components 10 and 12, in particular at least those which are turned toward the clothing 7 arriving in the direction of the arrow f5, are given angles a of the order of approximately 45° and at any rate such that the channels which are formed between adjacent flats 9 are open toward the outside, that is to say in the centrifugal direction, which facilitates the discharge of the waste and of the impurities. According to the solution in Figs 3 and 4, the distance pieces 10 have a continuous profile which is slightly set back in relation to the external surface of the clothings 7, while the outlines of the blades 12 reach and skim this clothing 7; the result is a toothed form in the view according to Fig. 4 of the group of adjacent components 10 and 12. According to the alternative in Figs 5 and 6, however, the distance pieces 10 also are given extensions 10A at their ends, in such a manner that these extensions 10A become level with the end points of the blades 12 to constitute a continuous and therefore not toothed front, as can be seen from the comparison between Figs 6 and 4; this continuous front constitutes a transverse cleaning blade which assists the discharge of the impurities through the interspaces between the adjacent flats 9. It is possible, as shown in Fig. 2, to envision the formation of channels, generally indicated extending by 16 and developed transversely in relation to the clothing of the cylinder 5, in the interspaces between adjacent flats. These channels 16 are open toward the clothing 7 and suction currents are formed in these which are capable of removing easily the impurities collected by the flats. It can be envisioned that the suction is brought about only at one end of the channel 16 or and advantageously at both the ends, to make the suction effect uniform over the entire front represented by the interspace between adjacent flats. The presence of the channels, which are of circular cross-section, may require that the profiles of the backs of the blades and of the distance pieces be shaped with a certain concavity. The structure described, in addition to offering the advantages already mentioned of assisting the cleaning of the clothing and the discharge of the impurities, also makes it possible easily to apply a system for cooling the working zones of the flats and of the clothing 7, so as to avoid the overheating of the components and the risk of plasticization of some of the, above all natural, impurities of cotton, which in the long run can cause an obstacle to the smooth running of the card. In fact, with the arrangement described, it is easy to create a hollow space I and a cooling current fo (Fig. 2) which flows over and licks and therefore cools the flats and the walls of the channels 16, thus bringing about that lowering of temperature which is required for the purposes mentioned above. It will be understood that the drawing only shows an illustrative embodiment which is given only by way of practical demonstration of the invention, it being possible for the invention to vary in form and arrangement without thereby leaving the scope of the idea which forms the invention itself. The presence of any reference numbers in the enclosed claims has the purpose of facilitating reading of the claims with reference to the description and to the drawing, and does not limit the scope of protection represented by the claims.

Claims: A card for cotton and for other uses, comprising fixed carding flats (9), in which at those ends turned toward the arriving clothing of the cylinder (5) are provided surfaces given an acute angle, functioning as cleaning members for the removal of the impurities, characterizing in said fixed flats (9) are provided blades (12) and distance pieces (10) interposed between the blades and in that the ends of the blades (12) and of the distance pieces (10) turned toward the arriving clothing are given an acute angle in order to function directly as cleaning members. The card as claimed in claim 1, wherein the front ends (10A) of the distance pieces (10) are extended to come side by side with the ends of the blades (12) formed at an acute angle, and are shaped like those ends of the blades so as to constitute a transverse continuos cleaning surface which is inclined in relation to the radial direction of the clothing (7) of the cylinder. The card as claimed in claim 1 or 2, wherein the acute-angled ends of the blades (12) and of the distance pieces (10) have an angular size of approximately 45°. The card as claimed in any preceding claim, wherein both ends of the blades (12) of the various adjacent flats are shaped at an acute angle to create between adjacent flats interspaces with ample opening in the centrifugal direction. The card as claimed in any preceding claim, which comprises in the spaces between adjacent flats channels (16) which are parallel to the flats (9) and open toward the clothing of the cylinder for defining pneumatic currents for suction of the impurities separated by said shaped ends for the discharge of these impurities. The card as claimed in any preceding claim, which comprises hollow spaces (I) around the flats and the walls of the channels for cooling currents.

Inventors: GIULIANI MARCELLO, GIULIANI, MARCELLO
Applicants: GIULIANI MARCELLO, GIULIANI, MARCELLO
Application year: 1992
Main classification: D01G15
IPC codes: D01G15