Title of Invention	A SPRING MECHANISM FOR A FLEXIBLE BEND OF A REVOLVING FLAT CARD
Abstract	A spring mechanism for a flexible bend of a revolving flat card, the spring mechanism being designed in such a way that it can be arranged on a flexible bend and thereby assists the elastic range of the flexible bend in at least one radial direction of movement. Fig. 2

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Spring mechanism for a flexible bend The present invention relates to a spring mechanism for a flexible bend of a revolving flat card. The flat region forms, together with the drum, the main carding zone and has the function of opening the flocks into individual fibers, of the separation of impurities and dust, of eliminating very short fibers, of the opening of neps and of parallelizing the fibers. Since the flats become clogged with dirt and fibers, it is necessary to clean these. The revolving flat was therefore developed, the flats being held together by means of a chain or belt and being combined to form an endless rotating band. Part is in direct use opposite the clothing of the drum, and the remaining part is transported further on, on its back, by deflecting rollers and can be cleaned and, if appropriate, ground. The flats slide into the working position when the clothings of the drum and flats are arranged opposite one another, onto curved guide rails which are called, inter alia, regulating bends, flexible bends, flex bends or sliding bends. These flexible bends stand approximately concentrically with respect to the drum, one on each side of the drum, and are fastened to the side pieces or drum plates of the card, specifically such that they can be readjusted easily and reliably. Since, due to the abrasion and wear of the clothings, the carding gap changes, the flexible bends must likewise be capable of being readjusted. For setting the flats, various flat setting systems have been developed over time. The oldest type of construction is a three-point regulation, as described in Johannsen, Handbuch der Baumwollspinnerei [Manual of Cotton Spinning] (Volume II, 1963, page 55ff), the flexible bend being supported at three points by carrying supports. The radius can be changed by setting toward or away from the drum center point. This presupposes, however, that the flexible bend ends must be pushed forward to their support points. For this purpose, at these support points, the flexible bend has slots through which setting means pass; if a flexible bend is set narrower, the radius decreases, and the flexible bend end is pushed forward, this position finally being fixed. This principle was developed further in five-point regulations, above all so that the weight of the flats can be distributed more effectively over the support points and the sag of the flexible bends can be prevented. This regulation operates with a fixed vertex, which can be changed only in the direction of the radius, but cannot shift to the side. The end and intermediate points can give way in both directions. One example of a recent five-point regulation is described, inter alia, in EP 787 841. Between the clothing of the flats and that of the drum, in the direct working position, a very narrow gap is formed which is called the carding gap. In the case of a revolving flat card for cotton spinning, the settings of the carding gap move in the range of 0.10 mm to 0.30 mm for cotton or up to 0.40 mm for chemical fibers. Consequently, the accuracy of the revolving flat elements, in particular of the flexible bend as such, and the setting of these elements in relation to one another are of great importance. However, depending on the clothing types selected, it may be necessary to provide different initial settings of the flexible bend in the range of up to 3 mm. The bandwidth of the settings means that the elastic properties of the flexible bends allows this bending, without the plastic range being reached. For this purpose, the flexible bends are mostly cast from a special alloy which has the necessary elasticity and can give way so as to assume the necessary shape. However, elastic range and the maximum bend associated with this are not always sufficient for the desired setting bandwidth. This effect becomes even more serious in the case of a smaller drum diameter of, for example, 1 m or less, since, with an identical variation in the setting, the actual bend is greater. For an optimal setting device, it is advantageous that the flexible bend is freely movable at its end both in the radial setting direction and in the circumferential direction. Possible fixings may impede or restrict the movement in the circumferential direction. However, due to the use of a bearing surface on the setting means at the end of the flexible bends, without any form of fixing of the flexible bends, the maximum radial setting bandwidth is restricted. Basically, both radial setting directions are desired: in the radial direction away from the center point in order to increase the carding gap and in the radial direction toward the center point in order to reduce the carding gap. If setting means are assumed which have only bearing surfaces at the outer ends of the flexible bends, then these setting means are only capable of butting against one another or of causing a radial setting away from the center point. The travel back toward the center point is brought about by the elastic properties of the flexible bends. The flexible bend has to be produced to the smallest radius and can be used only for increasing the radius. The setting range is thereby restricted. In the case of an overstretching of the flexible bends beyond the yield point, the flexible bend may experience plastic deformation and no longer returns to its original state. The object on which the invention is based is, therefore, to provide a device of the type initially mentioned which avoids said disadvantages. This object is achieved, according to the invention, by means of a device having the features of the independent patent claim 1. Owing to the inventive spring mechanism, the elastic properties of the flexible bends can be assisted. The spring force of the mechanism is arranged in such a way that, at least in one radial direction of the flexible bend, the elastic range of the flexible bend is assisted. As a result, a greater setting bandwidth can be achieved, preferably in the radial direction of the flexible bends, which has hitherto been covered only by the elastic range of the flexible bends. In the previous example, the spring mechanism according to the invention was oriented in the direction of the center point. A flexible bend with a spring mechanism arranged in this way no longer has to be produced to the smallest radius, but, instead, can also be produced to a medium flexible bend setting. For the settings away from the center point, the bearing surfaces of the setting means press the flexible bends away, since, to reduce the radius, the spring mechanism of the flexible bends assumes this function. The invention is explained in more detail below with reference to examples. Figure 1 shows a diagrammatic illustration of the card. Figure 2 shows an example of a spring mechanism according to the invention. Figure 3 shows an arrangement of an alternative spring mechanism according to the invention. Figure 4 shows an arrangement of an alternative spring mechanism according to the invention. Figure 1 shows a revolving flat card, for example the Rieter card C60, with a working width of 1.5 meters and with a drum diameter of 1 meter. Fiber flocks are transported through the various cleaning process stages by means of transport ducts (not shown) and are finally fed into the cleaner shaft 9 of the card. Instead of a cleaner shaft, a normal filling shaft may also be provided. This then transfers the fiber flocks as lap to the card. The feed device feeds the fiber flocks to the lickers-in 3. The lickers-in 3 open the fiber flocks and remove part of the dirt particles. The last licker-in roller transfers the fibers to the card drum 1. The card drum 1 cooperates with the flats 6 and at the same time parallelizes the fibers even further. The flats are cleaned by means of a flat cleaner 8 and, if appropriate, reground by means of a grinding device. After the fibers have partly executed a plurality of revolutions on the card drum, they are doffed from the card drum by the doffing roller 4, supplied to the doffing rollers in the doffing region 5 and finally deposited as a card sliver in a sliver lay in a can (not shown). The flats belong to a system of revolving flats 2, and in this case flats 6 are moved forward over the drum surface, mostly opposite to the direction of rotation of the drum, by means of a drive with the aid of an endless belt or a chain. The flats have at their ends flat end heads which slide directly or indirectly on the flexible bends 7. The undersides of the flats are provided with a clothing, for example with a sawtooth clothing or flexible clothings in the form of small hooks. The drum, too, has a clothing, what is known as a sawtooth clothing. A revolving flat set consists of around 70-120 flats, of which only some are in the working position. The number of flats in the working position depends, inter alia, on the diameters of the drum and on the revolving flat arrangement. On average, 20 to 46 flats are in the working position. A gap, called the carding gap, is present between the clothing of the drum and that of the flats. This carding gap is normally set at a constant distance over the entire contact zone between flat and drum. However, the gap may also be set to opening -carding gap becomes continuously larger - or to closing - the carding gap becomes continuously smaller. For controlling the setting, slots may be formed in the side of the bows, and the distance between the flat region and drum region can be measured by means of measuring gages. Figure 2 shows a first example of an inventive spring mechanism for a flexible bend 7. The flexible bend has in the middle means for setting 11 which are fastened to the flexible bend. The flexible bend can thereby be set to this position in both radial directions, but the setting point cannot be displaced laterally. The setting points 10 at the outer ends of the flexible bends are assigned only setting means which have a bearing surface for the flexible bend. As a result, these means can be set only so as to press the flexible bend radially upward away from the center point of the radius. Setting to a smaller radius can take place, without the spring mechanism, only due to the elastic properties within a restricted setting range, on the presumption that the flexible bend has been produced to the smallest desired radius. According to the invention, below the flexible bend is arranged a spring mechanism in the form of a leaf spring 12, in such a way that the spring force deforms the flexible bend in the radial direction toward the center point. The advantage is that this spring mechanism assists the radial setting toward the center point or takes over completely from the flexible bend. If, for example, the flexible bend is produced with a medium setting radius, then the spring is designed in such a way that its force corresponds to the smallest desired radius. The radial movement away from the center point, the setting means 10 and 11 operate, the means exerting only a pressure movement on the outer end of the flexible bends. For the travel toward the center point, either mainly the elastic range of the flexible bend and/or the spring mechanism 12 operate. In this example, the spring force of the leaf spring operates, above all, in a punctiform manner directly on the ends of the flexible bends and is preferably applied-above the bearing surface of the setting means 10. Preferably, the spring is mounted at the center point in such a way that it cannot execute a movement independently of the setting means 11 either in the circumferential direction or in the radial direction. Figure 3 shows a comparable example to figure 2, the flexible bend and the setting means being comparable to figure 2. Individual springs 13 together form the spring mechanism which also exerts a punctiform spring force on the outer setting points 10. In the event of a radial setting toward the center point, the individual springs pull the flexible bend along. Figure 4 also again shows a flexible bend 7 and setting means 10, 11, as described under figure 2. However, in this case the spring mechanism is now arranged in such a way that there is no punctiform force distribution, but, instead, the force distribution is distributed evenly as a uniform load over the circumference of the flexible bends in the circumferential direction. This may be achieved, for example, by the application of a second material 14 on the side of the flexible bends 7, to assist the elastic properties in the desired radial direction. See also the cross section in figure 4a. However, by a spring mechanism according to the invention being used, it would also be possible to select the material for the flexible bend differently. The elastic properties are no longer sufficient, but, instead, only deformability is sufficient. The assistance of the entire missing elastic range of the flexible bend can be compensated in the desired radial directions by means of a spring mechanism. Patent claims A spring mechanism for a flexible bend of a revolving flat card, characterized in that the spring mechanism is designed in such a way that it can be arranged on a flexible bend and can thereby assist the elastic range of the flexible bend at least in one radial direction of movement. The spring mechanism as claimed in claim 1, characterized in that the spring force can be opposite to the direction of the setting element. A flexible bend for a revolving flat card, characterized in that a spring mechanism as claimed in one of the preceding claims is arranged. The flexible bend as claimed in claim 3, characterized in that the spring mechanism exerts a force in a punctiform manner. The flexible bend as claimed in claim 3, characterized in that the spring mechanism exerts a uniform load in the circumferential direction of the flexible bend. The flexible bend as claimed in one of the preceding claims, characterized in that the spring mechanism contains a leaf spring. The flexible bend as claimed in claim 6, characterized in that the leaf spring exerts a force on the outer setting points. 8. The flexible bend as claimed in one of the preceding claims, characterized in that a second material 14 which assists the elastic properties in the desired radial direction is arranged on the sides of the flexible bend 7. 9. A card having a flexible bend with a spring mechanism as claimed in claims 1 to Dat&d this 26 day of October 2006 (ARINDAMPAUL) Of De PENNING & De PENNING AGENT FOR THE APPLICANTS

Documents:

3919-CHENP-2006 AMENDED PAGES OF SPECIFICATION 28-08-2012.pdf

3919-CHENP-2006 AMENDED CLAIMS 28-08-2012.pdf

3919-CHENP-2006 FORM-3 28-08-2012.pdf

3919-CHENP-2006 OTHER PATENT DOCUMENT 28-08-2012.pdf

3919-CHENP-2006 AMENDED CLAIMS 06-11-2012.pdf

3919-CHENP-2006 CORRESPONDENCE OTHERS 28-08-2012.pdf

3919-CHENP-2006 CORRESPONDENCE OTHERS 06-11-2012.pdf

3919-CHENP-2006 CORRESPONDENCE OTHERS 07-02-2012.pdf

3919-CHENP-2006 CORRESPONDENCE OTHERS. 23-11-2012.pdf

3919-CHENP-2006 EXAMINATION REPORT REPLY RECEIVED 10-10-2012.pdf

3919-CHENP-2006 AMENDED CLAIMS 23-11-2012.pdf

3919-CHENP-2006 AMENDED CLAIMS 24-04-2012.pdf

3919-CHENP-2006 AMENDED PAGES OF SPECIFICATION 24-04-2012.pdf

3919-CHENP-2006 EXAMINATION REPORT REPLY RECEIVED 24-04-2012.pdf

3919-CHENP-2006 FORM-1 24-04-2012.pdf

3919-CHENP-2006 FORM-18.pdf

3919-CHENP-2006 FORM-3 02-02-2007.pdf

3919-CHENP-2006 FORM-3 24-04-2012.pdf

3919-chenp-2006-abstract.image.jpg

3919-chenp-2006-abstract.pdf

3919-chenp-2006-claims.pdf

3919-chenp-2006-correspondnece-others.pdf

3919-chenp-2006-description(complete).pdf

3919-chenp-2006-drawings.pdf

3919-chenp-2006-form 1.pdf

3919-chenp-2006-form 26.pdf

3919-chenp-2006-form 3.pdf

3919-chenp-2006-form 5.pdf

3919-chenp-2006-pct.pdf