GB2473932A

GB2473932A - Carding element for a carding machine

Info

Publication number: GB2473932A
Application number: GB1015665A
Authority: GB
Inventors: Joachim Breuer; Christoph Farber
Original assignee: Truetzschler GmbH and Co KG
Current assignee: Truetzschler GmbH and Co KG
Priority date: 2009-09-23
Filing date: 2010-09-20
Publication date: 2011-03-30
Anticipated expiration: 2030-09-20
Also published as: DE102009042367A1; IT1400781B1; GB2473932B; ITMI20101691A1; BRPI1003723B1; CH701851A2; BRPI1003723A2; CN102021680B; CN102021680A; CH701851B1; GB201015665D0; BRPI1003723B8

Abstract

In an apparatus at a flat card or roller card, a carding element 23 has end regions and, between the end regions, an elongate body for covering a cylinder. The body includes a first part 24 provided with a fixing face (24b, figure 3a) for a clothing strip, which in operation faces the working region of the card, and a second part 28 serving as a rigidity-providing spine. The two parts 24, 28 are connected together. To provide an apparatus in which the carding element is dimensionally stable in operation even when subject to the effects of heat, the material and cross-section of the first part 24 provides homogeneous temperature distribution with a small heat gradient and the second part 28 counteracts heat related changes such or sagging of the first part. The second part may be made of a heat insulating material such as glass fibre reinforced plastics. Alternatively the first and second parts may be made of aluminium alloy with a thermally insulating layer (30, figure 5) between them. The heat insulating layer may extend over the upper and two lateral side surfaces of the first member. Ribs or clips (40, 41, figures 10 and 11) may provide lateral support for the spine 28.

Description

Carding element for a carding machine The invention relates to a carding element for a carding S machine, for example for a flat card or roller card.

It is known, in a fixed carding element, to have end regions each of which is formed for fixing to the frame of the card and, between the end regions, and to have an elongate body (carrying element) for covering the cylinder, wherein the body includes at least two plate-shaped parts, one part being provided with a fixing face for a clothing strip, which fixing face in operation faces inwards (in towards the working region of the card), the other part arranged on the first part serving as a rigidity-provider, and the two parts being connected together.

In cards of current mode of construction, in addition to the card top having flexible clothings, so-called fixed carding elements having all-steel clothings are also used for the carding process, the actual clothings being borne on high-precision carrier components, which are then mounted on the machine. Extruded aluminium profiled parts are now usually used as carrier components. Besides having numerous advantages such as, for example, low weight, high rigidity etc., these do have the disadvantage, however, that when heated on one side, which does happen in the case of carding, they undergo deformation to the heated side.

The taller the component, the greater is the rigidity but also the deformation under the influence of heat. This deformation results in a carding nip which is not constant, which in turn has the consequence of a technical carding result which is not optimal.

The fixed carding elements increasingly being used in flat cards and roller cards generally consist of a carrier profiled part and, fixed thereto, clothing strips (1 to 3 per carrier profiled part) . The carrier profiled parts for fixed carding elements are now constructed as extruded aluminium profiled parts that are closed on all sides. In the case of a known apparatus (EP 0 687 754 A), the carrying element is a hollow profiled part, the cross-sectional shape of which includes closed cavities. Over the length, cavities are entirely surrounded by closed wall surfaces -apart from the two end faces. The heat arising during the carding process is to a large extent given off to the outside by way of the fixed carding elements. The temperature gradient necessary therefor within the cross-section of the profiled part results in deformation of the fixed carding element. The greater that gradient, the greater is the deformation. In the case of cross-sections of profiled parts that are closed on all sides, relatively large temperature gradients come about which give rise to undesirably large deformations. In the case of those profiled parts, the enclosed air chambers furthermore have a disadvantageous effect, causing the profiled parts to act like thermal insulation and to raise the temperature level of the cylinder and adjacent components.

The heating gives rise, however, not only to thermal expansion over the entire working width of the card but also to heat gradients over the arrangements of the various components of the card. For example, a temperature of 45°C may come about at the cylinder surface. A fixed carding segment arranged adjacent to the cylinder will also approximately reach this temperature on the cylinder clothing side. In contrast, on that side of the carding segment which is remote from the cylinder, the carding segment, for constructional reasons (owing to the working width and the accuracy of the elements), has a back that is several centimetres tall (EP 0 383 479), and the temperature at that side will reach a substantially lower value (for example, 28°C) . The difference in temperature over a fixed carding segment can accordingly amount to several degrees Celsius. How large that temperature difference is will be dependent on the nature of the segment (construction, material), the carding work done (speed of rotation, production), the spacing of the element from the roller and how the heat produced can be removed.

This heat gradient causes sagging of the elements over the width of the card. This sagging gives rise to a narrower carding nip in the middle than towards the outsides. This gives rise to an uneven carding nip which becomes wider towards the outsides. This results in reduced carding quality and/or in worse nep disentanglement. It can likewise result in "lateral flight" of the fibres. This means that fibres collect, and even settle, in the edge region, especially outside the working width. These effects come about in a card having a working width of 1 metre but become greater with increasing working width, for example when the working width is greater than 1 metre, for example 1.2 metres or more. The anomalies which occur as a result of the above-mentioned effects cannot be disregarded here but rather are a problem for the overall carding quality of the card, The problem of thermal sagging is added to the mechanical sagging that becomes greater with increasing It is an aim of the invention to provide an apparatus of the kind described at the beginning that avoids or mitigates the mentioned disadvantages, especially wherein the carrying element is dimensionally stable in operation even when subject to the effects of heat.

The invention provides a fixed carding element for a carding machine, especially a flat card or roller card, having end regions each of which is formed for fixing to -4-.

the frame of the card and, between the end regions, having an elongate body for covering the cylinder, wherein the body includes at least a first part being provided with a fixing face for a clothing strip, which fixing face in operation faces inwards (in towards the working region of the card) and a second part arranged on said first part serving as a rigidity-provider, the two parts being connected together. In accordance with the invention the first part is configured and dimensioned to have a cross-section that makes possible a substantially homogeneous temperature distribution with a small heat gradient and the second part is arranged to counteract sagging of the first part. By way of illustration, the first part may have a substantially uniform cross-section, for example a rectangular cross-section, in both the longitudinal and transverse directions. By way of illustration, the second part may be arranged to extend longitudinally along the first part.

More particularly, the invention provides a carding element for use in a carding machine, having end regions arranged to be supported on a support member of said carding machine, and, extending between the end regions, an elongate body for covering the cylinder, wherein the elongate body comprises first and second parts, a first part being provided with a fixing face for a clothing strip, which fixing face in operation faces a clothed roller of the carding machine, and said second part being arranged on said first part and serving as a rigidity-provider, said first part having a cross-section that makes possible a substantially homogeneous temperature distribution with a small temperature gradient and said second part being arranged to counteract sagging of the first part.

As a result of the measures according to the invention, a considerable part of the heat is given off to the outside so that the carrying element remains dimensionally stable in operation even when subject to the effects of heat. An advantage lies in the fact that the body (carrying element) is composed of first and second parts, each of which for itself carries out the functions, on the one hand, of heating up and of giving off heat and, on the other hand, of providing rigidity. By this means, a carding nip that is as parallel as possible is produced. In preferred embodiments the heat is not, or is only minimally, transferred from the carrier to the rigidity-providing element, In some embodiments, heat transfer to the carrier may be reduced or prevented by thermally isolating the first and second parts from one another. In other embodiments, heat transfer to the carrier may be reduced or prevented by making the second part from a material of 1ow thermal expansion co-efficient. The carrier is substantially homogeneously heated and gives off the heat evenly to the outside.

The carrier element according to the invention for clothings exhibits no deformation, or deformation that is as minimal as is possible, due to the influence of heat. The resistance to bending in the longitudinal direction thereof is substantially increased. The carrier element herein is constructed of first and second parts the first part thereof being suitable for rapid heat removal and the second part ensuring the rigidity and precision of the component. The second part, especially, is not subject to deformation as a result of the influence of heat. This can be achieved by selection of suitable materials such as, for example, CF'RP or GF'RP or, however, by attachment of the first part of the carding element to the second part of the carrier part in thermally insulated manner.

The absent or reduced deformation ensures a constant carding nip over the working width of the machine. This results in better carded sliver and yarn quality.

The invention also provides an apparatus at a flat card or roller card, wherein at least one fixed carding element is present, having end regions each of which is formed for fixing to the frame of the card and, between the end regions, having an elongate body (carrying element) for covering the cylinder, wherein the body includes at least two plate-shaped parts, one part being provided with a fixing face for a clothing strip, which fixing face in operation faces inwards (in towards the working region of the card), the other part arranged on the first part serving as a rigidity-provider, and the two parts being connected together, characterised in that the material cross-section of the first part (carrier) makes possible a substantially homogeneous temperature distribution with a small heat gradient and the other part (rigidity-provider) counteracts sagging of the first part (carrier) Advantageously, the first part and the other part are made of different materials. Advantageously, the first part is attached in thermally insulated manner with respect to the other part. Advantageously, the first part and the other part together form a two-piece component.

Advantageously, the first part is constructed as a carrier plate. Preferably, the first part has a substantially rectangular cross-section. Advantageously, the first part is solidly constructed, that is, it includes within its cross-section no or substantially no void regions.

Preferably, the other part is built or constructed as a spine. Preferably, the other part has a substantially rectangular cross-section.

Advantageously, at least one additional rigidity-providing element which increases the bending resistance of the fixed carding element in its longitudinal direction is mounted on the carrier plate. Advantageously, the rigidity-providing element, seen in the longitudinal direction, extends from the middle towards its two ends.

Advantageously, the rigidity-providing element has a spacing from each of the ends which serves for fixing.

Preferably, the rigidity-providing element is connected to the carrier plate. Advantageously, the carrier plate is made of a metallic material. Preferably, the carrier plate is made of an aluminium alloy. Advantageously, the carrier plate is extruded. Advantageously, the rigidity-providing element is made of a non-metallic material. Preferably, the rigidity-providing element is made of plastic.

Preferably, the rigidity-providing element is made of a fibre-reinforced plastic, for example, a glass-fibre-reinforced plastic. Advantageously, the rigidity-providing element is made of a different material to the carrier plate. Advantageously, the specific weight of the rigidity-providing element is less than the specific weight of the carrier plate. The rigidity-providing element may be connected to the carrier plate by any suitable means, for example, by way of a fixing means, by way of adhesive means, or by welding. Preferably, the rigidity-providing means is connected to the carrier plate by screwing together, riveting or the like.

Advantageously, the material for the carrier plate has a high heat capacity. Preferably, the material for the carrier plate has a low thermal expansion coefficient.

In some embodiments, the carrier plate is provided with thermal insulation on its outward facing face.

Advantageously, the first part (carrier, carrier plate) is attached to the other part in thermally insulated manner.

Preferably, each zone is differently constructed and fulfils other (different) functions. Advantageously, there is present a heat zone, in which heating up and heat removal is carried out at the carrier (carding wall), and on the other hand a rigidity zone, in which a structure ensures rigidity only and is not involved in heating up/heat removal. Advantageously, the heat zone is made approximately of a smooth, solidly constructed, metal, rectangular profiled part. Preferably, the rigidity zone is made of a non-heat-conducting fibre-reinforced structure. Preferably, both zones are joined together, for example adhesively bonded, screwed, pressed together.

Advantageously, the face of the carding wall which is associated with the ambient air is provided with a corrugated shape or the like or other topographical structures (low) in order to increase the surface area.

Advantageously, the clothing strip is set against, for example screwed to, that carding wall (rectangular profiled part) In some embodiments, the rigidity zone consists of spines and/or fins. Advantageously, the spines and/or fins are joined, for example adhesively bonded, pressed, screwed together. Advantageously, the spines and/or fins have through-holes for improving the convection at the carding wall. Preferably, a rigidity-provider is associated with the carrier of heat-conducting material. Advantageously, the rigidity-provider has a small contact face with respect to the carrier. Advantageously, the rigidity-provider is made of a material having a low thermal expansion coefficient, low thermal conductivity, low heat capacity and a high Young's modulus. Preferably, the rigidity-provider is constructed as a spine along the carrier.

Advantageously, the rigidity-provider in the form of a spine is solidly constructed. Advantageously, the spine is made of a plastic or a fibre-reinforced plastic.

Preferably, the rigidity-provider consists of a spine in the longitudinal direction and fins arranged crosswise thereto. Preferably, the rigidity-provider comprising spine and fins is of open construction, that is to say without cavities.

Advantageously, the spine and/or fins have recesses and/or through-holes, so that better convection is brought about. In some embodiments, the spine is fixed to the carrier using clips. Preferably, the clips are made of spring steel and connect the spine to the carrier by a force-based connection. Preferably, the clips support the spine by a shape-based connection and are hooked into the carrier in a shape-based connection. Advantageously, the fins are screwed to the carrier. In some embodiments, the spine can move relative to the carrier, for example the spine is fixed to the carrier using elastic adhesive. In certain embodiments, the spine is fixed on the carrier by a shape-based connection. In certain embodiments, the spine is connected to the carrier by a force-based connection.

Advantageously, the fins are associated with the spine by screwing together, adhesive bonding or a shape-based connection. Advantageously, the fins are made of heat-conducting material or non-heat-conducting material.

Preferably, the clothing backing of the clothing strip is made of heat-conducting material. Advantageously, the clothing backing is solidly constructed, that is to say is made entirely of heat-conducting material and has no or substantially no cavities. Preferably, no cavities exist between the clothing and carrier. Preferably, a substantially homogeneous temperature distribution with a low heat gradient is present in the height direction and over the width of the carrier. Advantageously, the material cross-section of the carrier has a substantially homogeneous temperature distribution over the width.

Advantageously, the material cross-section of the carrier -10 -has a substantially homogeneous temperature distribution in the longitudinal direction. Advantageously, the carrier and/or the clothing backing has/have a concave bend on the inward facing side over the working width. Advantageously, the bend curvature is so selected that the correction of mechanical and/or thermal sagging over the working width is assisted. Preferably, the working width measures more than 1200 mm, for example 1300 mm. Preferably, the carrier for the at least one clothing strip is solidly constructed and is made of heat-conducting material. Advantageously, the outward facing face largely has a constant or substantially constant spacing from the inward facing fixing face.

Certain illustrative embodiments of the invention will be described hereinafter in greater detail with reference to the accompanying drawings, in which: Fig. 1 is a diagrammatic side view of a flat card having one or more fixed carding elements and/or card top bars according to the invention; Fig. 2 shows a carding element according to a first embodiment of the invention, and a portion of a side screen of a flat card, with spacing between the carding element clothing and the cylinder clothing; Fig. 2a shows the carding element according to Fig. 2 in detail; Fig. 3 shows, in a side view, a fixed carding element according to the invention, with a spine, carrier, clothing strip and clothing, the carrier being rectangular in cross-section; Fig. 3a shows, in an exploded view, part of the carrier, the clothing backing and the clothing of the element of Fig.3; -11 -Fig. 4 shows an embodiment in which the spine and the carrier are made of different materials; Fig. 5 shows an embodiment in which the spine and the carrier are made of the same material and the spine is attached in thermally insulated manner with respect to the carrier; Fig. Sa shows, in a view according to part of Fig. 5, the carrier provided with an insulating layer; Fig. 6 shows, in a side view, a side screen of a flat card with two adjusting bends (extension bends) for stationary fixed carding elements in the pre-and post-carding regions; Fig. 7 is a section I-I through the flat card of Fig. 6, in diagrammatic form, through an adjusting bend (extension bend) with a fixed carding element on a side screen on one side, with a corresponding view of the other side; Fig. 8 shows, in a front view, a clothing backing which has a concave bend on the side facing the cylinder; Fig. 9 shows, in an exploded front view, a carrier and a clothing backing each having a concave bend on the side facing the cylinder and each having a convex bend on the side remote from the cylinder; Figs. lOa show, in a side, front and top view, an to lOc embodiment in which supporting fins are associated with the spine; -12 -Fig. 11 shows an embodiment in which the spine is fixed to the carrier using clips; and Fig. 12 shows an embodiment having a shape-based connection between the spine and the carrier.

With reference to Figure 1, a carding machine, for example a flat card TO made by Trutzschler GmbH & Co. KG of Monchengladbach, Germany, has a feed roller 1, feed table 2, lickers-in 3a, 3b, 3c, cylinder 4, doffer 5, stripper roller 6, nip rollers 7, 8, web guide element 9, sliver funnel 10, delivery rollers 11, 12, revolving card top 13 with card top guide rollers l3a, 13b and flats 14, can 15 and coiler 16. Reference letter N denotes the centre point (axis) of the cylinder 4. Reference numeral 4a denotes the clothing and reference numeral 4b the direction of rotation of the cylinder 4. The arrow A indicates the working direction, The directions of rotation of the rollers are indicated by curved arrows drawn inside the rollers.

In the pre-carding zone (between the licker-in 3c and the rearward card top guide roller 13a) a plurality of fixed carding elements 23' according to the invention are located opposite the cylinder 4, and in the post-carding zone (between the forward card top guide roller l3b and the doffer 5) a plurality of fixed carding elements 23'' according to the invention are located opposite the cylinder 4, which are each located next to one another, seen in the circumferential direction of the cylinder 4.

With reference to Fig. 2, an approximately semi-circular rigid side screen 18 is fixed laterally to the machine frame (not shown) on each side of the card, on the outside of which side screen 18 there is concentrically mounted, in the region of the periphery, an arcuate rigid support element 19, which has a convex outer face 19' as the bearing face and also an underside 19' . The card of Fig. 1 -13 -comprises at least one fixed carding element 23 according to the invention, which has at both its ends support faces, which are supported on the convex outer face 19' of the support element 19 (for example, an extension bend) (see Fig. 7) . On the underside of the carrier 24 (carrier plate) of the fixed carding element 23 there are mounted clothing backings 25k, 252 each having clothings 26k, 262 (carding clothings) . Reference numeral 21 denotes the circle of tips of the clothings 26k, 262. The cylinder 4 has on its circumference a cylinder clothing 4a, for example a sawtooth clothing. Reference numeral 22 denotes the circle of the tips of the cylinder clothing 4a. The spacing between the circle of tips 21 and the circle of tips 22 is denoted by reference letter a and is, for example, 0.20 mm.

The spacing between the convex outer face 19' and the circle of tips 22 is denoted by reference letter b. The radius of the convex outer face 19' is denoted by reference letter r5 and the radius of the circle of tips 22 is denoted by reference letter r2. The radii r5 and r2 intersect at the centre point N of the cylinder 4. The fixed carding element 23 according to Figure 2 consists of a carrier 24 (carrier plate) and two clothing strips 27k, 272, each of which comprises a clothing backing 25 and 252, respectively, each having clothings 26 and 262, respectively. The clothing strips 27k, 272 (carding elements) are arranged one after the other in the direction of rotation (arrow 4b) of the cylinder 4, with the clothings 26w, 262 (sawtooth wire portions) and the clothing 4a of the cylinder 4 being located opposite one another. The carrier 24 is made of an aluminium alloy and is extruded. The clothing backings 25a, 252 are fixed to the carrier 24 by means of screws 31a and 31b, respectively. The mass of the carrier 24 is arranged -14 -tangentially to the cylinder 4, seen in the width direction b.

The surface of the clothing tips can, when seen in a side view, be concavely curved. The circle of tips 21 of the clothings 26, 262 is in that case concentrically or eccentrically arranged relative to the circle of tips 22 of the cylinder clothing 4a. The surface of the clothing tips can, when seen in a side view, be formed straight. In this arrangement, the circle of tips of the clothings 2i, 262 is an approximation.

In the embodiment of Fig. 3, the fixed carding element 23 according to the invention has a plate-shaped carrier 24 (carrier plate); on the fixing face 24b thereof which in operation faces inwards (in the direction of the cylinder 4) there is mounted a clothing strip 27 (carding element) . The clothing strip 27 consists of a clothing backing 25, to which two clothings 26 and 262 are fixed.

The clothing backing 25 is fixed to the carrier 24 by screws 3la, 31b, for example, in the manner shown in Figure 2. The carrier 24 is constructed as a flat carrier plate, which has a height h2, a width b and a length 1 (corresponding to the longitudinal direction L in Fig. 7).

Reference h2 denotes the height of the carrier 24 and clothing backing 25, and reference h3 denotes the height of the carrier 24, the clothing backing 25 and the clothing 26. As shown in the exploded view in Fig. 3a, the carrier 24 has an upper face 24a and a lower face 24b, and the clothing backing 25 has an upper face 25a and a lower face 25b. The carrier 24 is of substantially uniform cross-section and has, for example, the following dimensions: h1 24 mm, b = 72 mm, 1 = 1300 -.

The fixed carding element 23 comprises a carrying element 29 consisting of two plate-shaped parts, the carrier 24 and a rigidity-provider 28 (rigidity-providing -15 -element) . The rigidity-providing element 28 is in the form of a spine (being for example in the form of an elongate planar member that is positioned at right angles to the upper face 24a) and is fixed to the upper face 24a of the carrier 24. Reference b1 denotes the width of the rigidity-providing element 28 and reference h4 the height. For example, the width b1 = 20 mm and the height h4 = 60 mm.

In the embodiment of Fig. 4, the carrier plate 24 is made of an aluminium alloy and the rigidity-providing element 28 (spine) of glass fibre reinforced plastic. As a result, the two parts are differently made up and fulfil different functions. The carrier plate 24 forms a heat zone, in which heating up and heat removal take place. The rigidity-providing element 28 forms a rigidity zone in which the structure ensures rigidity only but, by virtue of the low thermal conductivity, is not involved in heating up/heat removal, The two-piece carrier element 29 forms a T-shaped carrier in cross-section. The spine 28 is connected to the carrier 24 by a force-based connection.

In the embodiment of Fig. 5, the carrier plate 24 and the rigidity-providing element 282 (spine) are made of an aluminium alloy. At the location where the two parts are connected, there is provided between the carrier plate 24 and the rigidity-providing element 282 a thermally insulating layer 30 which prevents heat passing over from the carrier plate 24 into the rigidity-providing element 282. In the case of this arrangement too, the cross-section of the carrier element 29 forms a T-shaped carrier, As shown in Fig. 5a, the carrier plate 24 is provided with a thermally insulating layer 31 at its upper face 24a and at its two lateral longitudinal faces 24c and 24d.

In the embodiments shown in Figs. 4 and 5, the rigidity-providing element 28 can be connected to the carrier plate 24 by way of an adhesive layer, or by welding, riveted connections, screwed connections or the like.

In the card flat according to Fig. 6, a side screen l8a (the side screen 18b on the other side is shown in Fig. 7) is shown with a setting bend 17a (flexible bend) for the revolving card flats 14 and two setting bends l9'a, 19' a (extension bends) for stationary functional elements (fixed carding elements, extraction hoods) . The setting bend 17a is provided in the region of the upper periphery of the side screen iSa. Two setting bends 19'a, 19' a are provided in the two lateral peripheral regions of the side screen l8a+ As positioning devices, positioning spindles 36' to 361V and 37' to 37' are associated with each of the setting bends 19'a and 19''a, respectively. The positioning spindles 36' to are supported by their one end on a flange 18'' of the side screen iSa and by their other end on the setting bend 19'a. The positioning spindles 37' to 371V are supported by their one end on a flange 18''' of the side screen iSa and by their other end on the setting bend 19' a. The setting bend 19'a is arranged between the licker-in 3c and the card top guide roller 13a, that is to say in the pre-carding region. On the setting bend 19'a there are mounted stationary functional elements, which in the example of Figure 6 are non-clothed cover elements 32a to 32c, three fixed carding elements 23', to 23'3 according to the invention and three extraction hoods 33a, 33b, 33c.

The setting bend 19''a is arranged between the card top guide roller l3b and the doffer 5, that is to say in the post-carding region. On the setting bend 19' a there are mounted stationary functional elements, which in the example of Fig. 6 are six fixed carding elements 23'', to 23' 6 according to the invention and three extraction hoods 34a to 34c. Reference 35a denotes a part of the -17 -machine frame, and reference 38a denotes a bottom carding bend.

Fig. 7 shows part of the cylinder 4 of the flat card of Fig.6, together with a cylindrical surface 4f of its wall 4e and the cylinder ends 4c, 4d (radial supporting elements) . The surface 4f is provided with a clothing 4a, which in this example is provided in the form of wire with sawteeth. The sawtooth wire is drawn onto the cylinder 4, that is to say is wound around the cylinder 4 in tightly adjacent turns between side flanges (not shown), in order to form a cylindrical work surface provided with tips.

Fibres should be processed as evenly as possible on the work surface (clothing) . The carding work is performed between the clothings 26k, 262 (see Fig. 2) and 4a located opposite one another (see Fig. 2) and is substantially influenced by the position of one clothing with respect to the other and by the clothing spacing a between the tips of the teeth of the two clothings 26k, 262 and 4a. The working width of the cylinder 4 is the determining factor for the working width L of all other work elements of the card, especially for the revolving card top flats 14 (Fig. 1) or fixed card flats 23', which together with the cylinder 4 card the fibres evenly over the entire working width. In order to be able to perform even carding work over the entire working width L, the settings of the work elements (including those of additional elements) must be maintained over that working width L. The working width is, for example, 1300 mm. The cylinder 4 itself can, however, be deformed as a result of the drawing-on of the clothing wire, as a result of centrifugal force or as a result of heat produced by the carding process. The shaft ends of the cylinder 4 are mounted in bearings located on the stationary machine frame (not shown) . The diameter, for example 1250 mm, of the cylindrical surface 4f, that is to -18 -say twice the radius r1, is an important dimension of the machine. The side screens 18a, 18b are fixed to the two machine frames 35a, 35b (cf. Fig. 6) . The extension bends 19a and 19b are fixed to the side screens iSa, 18b. The circumferential speed of the cylinder 4 is, for example, m/sec. The fixed carding elements 23' according to the invention are fixed to the extension bends 19a, 19b using screws 20a, 20b. References Si and 52 denote the end faces of the fixed carding element 23hj.

With reference to Fig. 8, one form of clothing backing which may be used in some carding elements according to the invention has a flat face 25a. On the inward facing side, the fixing face 25b for the clothings 26, 262 has a concave bend over the working width L, which is introduced by means of machining-down or by non-machining-down means.

This assists the correction of thermal sagging in operation. The zenith of the concave bend can, depending on the particular application, be located between 0.04 and 0.6 -relative to a straight line. Reference h5 denotes the spacing of the zenith from the straight line.

In an arrangement illustrated in Fig. 9, both the carrier 24 and also the clothing backing 25 have1 over the working width L, a concave bend on the inside 24b and 25b, respectively, as well as a concave bend on the outside 24a and 25a. The spacings between the respective insides and outsides of the carrier 24 and the clothing backing 25 are parallel or substantially parallel.

In the embodiment of Figures lOa to lOc, the rigidity-provider consists of a spine 28 and fins 40 to 40 arranged crosswise thereto. The fins 40 to 405 are fixed to the carrier 24 by means of screws (not shown) . The fins to 40 are fixed to the spine 28 by means of an adhesive connection (not shown) -19 -In an embodiment shown in Fig. 11, the spine 28 is fixed to the carrier 24 using clips 41. The clips 41 are made of, for example, spring steel and connect the spine 28 to the carrier 24 by means of a force-based connection. Grooves S can be provided in the longitudinal sides 24c, 24d of the carrier 24 for the purpose.

In the embodiment of Fig. 12, the spine 28 is connected to the carrier 24 by means of a shape-based connection.

Suitable selection of a material combination and a structural arrangement are fundamental.

Preferred material properties: Carrier Spine * thermal expansion coefficient low low * thermal conductivity high low * heat capacity high low * Young's modulus high high Preferred structural arrangement: * The carrier 24 for the clothing strip 27 is solidly constructed, that is to say without cavities.

* The carrier 24 for the clothing strip 27 is made of heat-conducting material.

* The mass of *the carrier 24 is arranged substantially tangentially, preferably concentrically, with respect to the drum 4, that is to say no heat-conducting ribs or spines protrude from the carrier 24; it does not have a U-shape or T-shape but rather, for example, the carrier 24 has a rectangular profile.

* Only spines or ribs not made of heat-conducting material protrude from the carrier 24.

-20 -Advantageous material combinations: a) Material of the carrier: heat-conducting material, for example steel, aluminium, copper, magnesium.

b) Material of the spine: plastic, or GFRP, that is to say glass fibre reinforced plastic.

The objective is to produce a minimal heat gradient radial to the drum, that is to say over the overall height (compact construction) . This is achieved as a result of the fact that the surface of the carrier 24 has a temperature that is as high as possible and the component has no substantially projecting parts.

With the apparatus according to the invention the intention is less to compensate the thermal deformation than to minimise the cause of the deformation, by producing a small temperature gradient in the solidly constructed carrier.

The fixed carding element 23 must, on the one hand, fulfil the function of rigidity and, on the other hand, take up heating and irradiate heat. In order to obviate such disadvantages, a "two-zone" fixed carding element composed of two components is produced according to the invention. Each of the two components for itself fulfils one of the above-mentioned functions of heating up and giving off heat, and of providing rigidity. By this means, the "two-zone" fixed carding element satisfies the requirements for a carding nip that is as parallel as possible.

The clothing strip 27 is screwed against the carrier 24 (carding wall) . This carding wall is solidly constructed and rectangular and, for example, 15 mm thick. There are no ribs or other projecting surfaces on it. As a result, the heat is homogeneously distributed and the carding wall undergoes almost no deformation. The irradiation of heat -21 -takes place directly at the carding wall, because the ambient air flows along this wall. In order to avoid deformation during handling, the carding wall is provided with rigidity by means of a structure of fibre-reinforced materials. This consists of a vertically extending spine about 45 mm in height which extends over the length of the carrier 24. This spine is in turn laterally supported by means of fins. In order to obtain a non-heat-conducting rigid structure, an economical glass fibre reinforced plastic, for example GFRP, is advantageous. The spine is connected, bonded etc. to the fins. It is advantageous that the structure does not take heat away from the carding wall. As a result, a fixed carding element is produced which combines high bending rigidity with low weight. The special feature in this is the clear separation of the functions of irradiating heat at the carding wall and of providing the fixed carding element with rigidity as a result of a fibre reinforced material structure. As a result of this separation, the "two-zone twin-top" meets the requirement of minimum deformation on heating and also of withstanding handling without deformation.

The invention has been explained using the example of a fixed carding element 23. Construction as a revolving card top flat 14 is likewise included.

Claims

-22 -Claims 1. A carding element for use in a carding machine, having end regions arranged to be supported on a support member of said carding machine, and, extending between the end regions, an elongate body for covering the cylinder, wherein the elongate body comprises first and second parts, a first part being provided with a fixing face for a clothing strip, which fixing face in operation faces a clothed roller of the carding machine, and said second part being arranged on said first part and serving as a rigidity-provider, said first part having a cross-section that makes possible a substantially homogeneous temperature distribution with a small temperature gradient and said second part being arranged to counteract sagging of the first part.
2. A carding element according to claim 1, wherein the first part and the second part are made of different materials.
3. A carding element according to claim 1 or claim 2, wherein said first part is attached in thermally insulated manner with respect to said second part.
4. A carding element according to any one of claims 1 to 3, wherein the first part and the second part together form a two-piece component.
5. A carding element according to any one of claims 1 to 4, wherein said first part is constructed as a carrier plate *
6. A carding element according to any one of claims 1 to 5, wherein at least one of said first and second parts has a substantially rectangular cross-section.-23 - 7, A carding element according to any one of claims 1 to 6, wherein said first part is solidly constructed.8. A carding element according to any one of claims 1 to 7, wherein said second part is built or constructed as a spine that extends longitudinally with respect to said elongate body.9. A carding element according to any one of claims 1 to 8, wherein said second part has a substantially rectangular cross-section.10. A carding element according to any one of claims 1 to 9, wherein said first part is an elongate plate and said second part is so mounted on said elongate plate that it increases the bending resistance of the fixed carding element in its longitudinal direction.11. A carding element according to any one of claims 1 to 10, wherein the second part, seen in the longitudinal direction, extends from the middle of the first part towards its two ends.12. A carding element according to any one of claims I to 11, wherein the second part is spaced from each of the ends of the first part and the ends of said first part form said end regions.13. A carding element according to any one of claims 1 to 12, wherein said second part is connected to the first part.14. A carding element according to any one of claims 1 to 12, wherein the first part is made of a metallic material.15. A carding element according to claim 14, wherein the first part is made of an aluminium alloy.16. A carding element according to any one of claims 1 to 15, wherein the first part is extruded.17. A carding element according to any one of claims 1 to 16, wherein the second part is made of a non-metallic material.-24 - 18. A carding element according to any one of claims 1 to 17, wherein the second part is made of plastic.19. A carding element according to claim 18, wherein the second part is made of a fibre-reinforced plastic.20. A carding element according to claim 19, wherein a glass fibre reinforced plastic is used for the rigidity-providing profiled part.21. A carding element according to any one of claims 1 to 20, wherein the specific weight of the second part is less than the specific weight of the first part.22. A carding element according to any one of claims 1 to 21, wherein the second part is connected to the first part by way of a fixing means.23. A carding element according to any one of claims 1 to 21, wherein the second part is connected to the first part by way of adhesive means.24. A carding element according to any one of claims 1 to 21, wherein the second part is connected to the first part by welding.25. A carding element according to any one of claims 1 to 21, wherein the second part is connected to the first part by screwing together or riveting.26. A carding element according to any one of claims 1 to 25, wherein the first part is made from a material that has a high heat capacity.27. A carding element according to any one of claims 1 to 26, wherein the first part is made from a material that has a low thermal expansion coefficient.28. A carding element according to any one of claims 1 to 27, wherein the first part is provided with thermal insulation on its outward facing face.29. A carding element according to any one of claims 1 to 28, wherein the first part is attached to the other part in thermally insulated manner.-25 - 30. A carding element according to any one of claims 1 to 29, wherein there is present a heat zone, in which heating up and heat removal is carried out at the first part, and on the other hand a rigidity zone associated with the second part, in which a structure ensures rigidity only and is not involved in heating up/heat removal.31. A carding element according to claim 30, wherein the heat zone is made approximately of a smooth, solidly constructed, metal, rectangular profiled part.32. A carding element according to claim 30, wherein the rigidity zone is made of a non-heat-conducting fibre-reinforced structure.33. A carding element according to any one of claims 30 to 32, wherein both zones are joined together.34. A carding element according to any one of claims 1 to 33, wherein an exposed face of the first part to which a clothing is attached is provided with a corrugated shape or other topographical structures in order to increase the surface area.35. A carding element according to claim 34, wherein the clothing is set against the exposed face.36. A carding element according to any one of claims 30 to 35, wherein the rigidity zone consists of spines and/or fins.37. A carding element according to claim 36, wherein the spines and/or fins are joined together.38. A carding element according to claim 36 or claim 37, wherein the spines and/or fins have through-holes for improving the convection at the carding wall.39. A carding element according to any one of claims 1 to 38, wherein the first part is of heat-conducting material.40. A carding element according to any one of claims 1 to 39, wherein the second part has a small contact face with respect to the first part.41. A carding element according to any one of claims 1 to 40, wherein the second part is made of a material having a low thermal expansion coefficient, low thermal conductivity, low heat capacity and a high Young's modulus.42. A carding element according to any one of claims 1 to 41, wherein the second part is constructed as a spine along the first part.43. A carding element according to claim 42, wherein the second part in the form of a spine is solidly constructed.44. A carding element according to claim 42 or claim 43, wherein the spine is made of a plastic or a fibre-reinforced plastic.45. A carding element according to any one of claims 42 to 44, wherein the second part consists of a spine in the longitudinal direction and fins arranged crosswise thereto.46. A carding element according to claim 45, wherein the second part comprising spine and fins is of open construction, that is to say without enclosed void regions.47. A carding element according to claim 45 or claim 46, wherein the fins are associated with the spine by screwing together, adhesive bonding or a shape-based connection.48. A carding element according to any one of claims 45 to 47, wherein the fins are made of heat-conducting material or non-heat-conducting material.49. A carding element according to any one of claims 42 to 48, wherein the spine and/or fins have recesses and/or through-holes, so that better convection is brought about.50. A carding element according to any one of claims 42 to 49, wherein the spine is fixed to the first part using clips.51. A carding element according to claim 50, wherein the clips are made of spring steel and connect the spine to the carrier by a force-based connection.-27 - 52. A carding element according to claim 50 or claim 51, wherein the clips support the spine by a shape-based connection and are hooked into the carrier in a shape-based connection.53. A carding element according to any one of claims 42 to 52, wherein the spine and/or fins are screwed to the carrier.54. A carding element according to any one of claims 42 to 53, wherein the spine is movable relative to the first part.55. A carding element according to any one of claims 42 to 54, wherein the spine is fixed on the first part by a shape-based connection.56. A carding element according to any one of claims 42 to 55, wherein the spine is connected to the carrier by a force-based connection.57. A carding element according to any one of claims 1 to 56, further comprising a clothing strip having a clothing backing made of heat-conducting material.58. A carding element according to claim 57, wherein the clothing backing is made substantially entirely of heat-conducting material and has substantially no enclosed cavities.59. A carding element according to any one of claims 1 to 58, wherein there are no cavities between the clothing and carrier.60. A carding element according to any one of claims 1 to 59, wherein a substantially homogeneous temperature distribution with a low heat gradient is present in the height direction and over the width of the first part.61. A carding element according to any one of claims 1 to 60, wherein the material cross-section of the carrier has a substantially homogeneous temperature distribution in the longitudinal direction.-28 - 62. A carding element according to any one of claims 1 to 64, wherein the first part and/or a backing of the clothing has/have, on the side facing the working region of the card, a concave bend over the working width.63. A carding element according to claim 62, wherein the bend curvature is so selected that the correction of mechanical and/or thermal sagging over the working width is assisted.64. A carding element according to any one of claims 1 to 63, wherein the working width measures 1200 -or more.65. A carding element according to any one of claims 1 to 67, wherein the first part is constructed with substantially no enclosed void regions and is made of heat-conducting material.66. A carding element according to any one of claims 1 to 65, wherein an outward facing face of the first part opposite the fixing face has a constant or substantially constant spacing from the fixing face.67. A carding element for use in a carding machine, having end regions arranged to be supported on a support member of said carding machine, and, between the end regions, having an elongate body for covering the cylinder, wherein the elongate body comprises first and second parts, a first part being provided with a fixing face for a clothing strip, which fixing face in operation faces a clothed roller of the carding machine, and said second part being arranged on a said first part, the first part consisting of an elongate planar member of substantially uniform thickness and the second part serving as a rigidity-provider for counteracting heat-dependent changes in configuration of the first part.68. A carding element according to any one of claims 1 to 67 for use as a fixed carding element, the carding element -29 -further comprising end regions formed for fixing the carding elements to a frame of a carding machine.69. A carding element according to any one of claims I to 68, for use as a card top flat in a revolving card top.70. An apparatus at a flat card or roller card, wherein at least one fixed carding element is present, having end regions each of which is formed for fixing to the frame of the card and, between the end regions, having an elongate body (carrying element) for covering the cylinder, wherein the body includes at least two plate-shaped parts, one part being provided with a fixing face for a clothing strip, which fixing face in operation faces inwards (in towards the working region of the card), the other part arranged on the first part serving as a rigidity-provider, and the two parts being connected together, wherein the material cross-section of the first part (carrier) makes possible a substantially homogeneous temperature distribution with a small heat gradient and the other part (rigidity-provider) counteracts sagging of the first part (carrier) 71. A carding element substantially as described herein with reference to and as illustrated by any of Figs.1, 2, 2a, 3, 3a, 4, 5, 5a, 6 to 9, lOa to lOc, 11 and 12, 72. A carding machine comprising one or more carding elements according to any one of the preceding claims.