Tooth for a flat-top card clothing of a carding machine, and flat-top card clothing for the flat bar of a carding machine

Abstract

The invention relates to a tooth for a card clothing support (16a) of a flat bar (16) of a carding machine, wherein the tooth is provided with a single crank along its length from the tooth base (16c) to the tooth tip (16d). The invention also relates to a flat-top card clothing (16) for a flat bar (14) of a carding machine, comprising a card clothing support (16a) having such teeth (16b).

Description

[0001] Title: Tooth for a teasel cover set and cover set for the teasel cover rod

[0002] Description

[0003] The invention relates to a tooth for a cover assembly of a teasel and a cover assembly for the cover rod of a teasel.

[0004] In practice, flexible attachments are predominantly used for carding combs. These attachments comprise attachment carriers made of elastic, multi-layered fabric and embedded hooks, also called attachment points or teeth, which are bent from round or oval wire and equipped with a bend (a kink) to flex under load and return to their original position when unloaded. Attachment carriers can be designed as a continuous narrow or wide band. The teeth are inserted and anchored into the attachment carrier.

[0005] When using circumferential cover bars on the carding machine, the distance between the tips of the cover bars' teeth and the tips of the drum's teeth is in the range of 0.05 to 0.2 mm. This distance can be quickly reduced by the thermal expansion of the carding machine. If the tips of the covers touch, or if the distance is so small that an electrical contact can jump, the carding machine, if equipped with contact detection between the covers, may shut down due to a potential collision, or the carding machine itself may be damaged. According to current technology, the teeth and cover carriers are designed in such a way that the teeth of the covers can bend slightly during the carding process, and the absolute height above the covers can increase slightly. This increases the risk of contact with the drum covers, potentially leading to a collision between the components.

[0006] DE 102007 037 055 A1 discloses a tooth for the drum holder of a carding drum, in which the upper tooth length is reduced to improve carding performance. This is intended to increase nit shedding and reduce the number of carding drums lost. The document makes no mention of the tooth bending under load and thus of the tooth tip shifting towards the drum holder. Prior art drum holders are made of several layers of cotton fabric, often in combination with layers of rubber. Cotton has the property of a comparatively high moisture absorption rate. This can cause the teeth embedded in such a layer to begin to rust. Furthermore, pinsetting the teeth into the drum holder is more difficult when using cotton.

[0007] Based on this, however, there is still a need to modify the tooth geometry so that the absolute height of the teeth cannot increase under bending stress, thus preventing collisions with the drum's drum assembly. Furthermore, the cover assembly should be optimized, as the associated assembly carrier also influences the tooth's bending behavior. In particular, the pin setting should be improved and potential tooth corrosion reduced.

[0008] It is therefore the object of the invention to provide an improved tooth for a cover set, as well as to design a cover set for a cover bar of a carding machine in such a way that the bending behavior of the tooth according to the invention is improved.

[0009] The problem underlying the invention is solved by a tooth for the lid assembly that is simply cranked along its length from the root to the tip. The tooth has a lower tooth section and an upper tooth section, which are connected by a crank. Thus, for the same tooth height, the tooth has an increased lower tooth length (or length of the lower tooth section), with the ratio of lower tooth length to tooth height being 72% to 85%, preferably 73% to 76%. The crank of the tooth is thereby shifted towards the tip, reducing the radius when the tooth bends under load. The tooth tip therefore has a reduced tendency to move from the top of the lid assembly to the drum assembly. Preferably, the upper tooth length (or length of the upper tooth section) is 2.3 mm to 2.5 mm, with a tooth height of 7.5 mm.

[0010] In other words, the tooth – viewed from the side – can simply be cranked along its length from the base to the tip. "Along its length from the base to the tip" can refer to the axial direction of the tooth from the base to the tip.

[0011] In particular, the upper tooth length extends parallel to the upper tooth segment from the offset to the tooth tip. Similarly, the lower tooth length extends parallel to the lower tooth segment from the tooth base to the offset. A further improvement can be achieved by having each tooth bend around two bending points under load, the first bending point being located within the crown set between the uppermost felt layer and the veneer layer, and the second bending point being formed by the offset.

[0012] A modified working angle can be formed by a vertical line and the curved inner surface of the upper tooth length at the tooth tip, and preferably ranges between 12 and 20 degrees. Reducing the working angle (AW) results in less aggressive carding, which is further enhanced by the altered curvature of the tooth under load during carding. This leads to a longer service life for the teeth.

[0013] With this geometry, a breast angle of 70 degrees to 78 degrees can result between the top of the lid set and the inside of the upper tooth length.

[0014] With a tooth height ZH of 7.5 mm, the lower tooth length can be at least 5.4 mm, preferably at least 5.5 mm. Simultaneously, the insertion angle EW, at which the tooth is inserted into the attachment holder, can be reduced to 65 to 70 degrees. The insertion angle can be formed by the top surface of the attachment holder and the outer surface of the tooth, where the offset is located. This results in two modified bending points. The first bending point for the tooth can be located within the attachment holder, specifically between the uppermost felt layer and the polymer cover layer, which can serve as abutment. The second bending point can be formed by the offset. Consequently, the tooth can bend around two points in such a way that an increase in tooth height under load is prevented.

[0015] Preferably, the breast angle is 70 degrees to 78 degrees between the top of the cover assembly and the inside of the upper tooth length.

[0016] Since the working angle is complementary to the chest angle, the optimal carding action of the tooth in the lid set can be described by the ratio of the insertion angle to the chest angle of 83% to 100%, regardless of the geometric lengths of the tooth.

[0017] The tooth, which can also be referred to as a wire set, can consist of or be made of flat wire, round wire or biconvex wire.

[0018] The tooth can have a contour, which can be designed as a side bevel and / or back bevel. Contouring refers to a targeted geometric modification of the tooth, primarily intended to improve cutting performance, reduce cutting resistance, or optimize chip removal. The contour can be designed as a side bevel and / or back bevel, although other modifications such as chamfers or radii are also possible. The contour can be limited to specific sections of the tooth, such as the upper portion, or extend beyond the offset into the lower portion. By applying the contour in different areas, the tooth's adaptation to various operating conditions and material properties can be specifically tailored.

[0019] The lid assembly according to the invention comprises an assembly carrier into which a plurality, or several, of the teeth according to the invention are inserted. Preferably, all teeth of the lid assembly are formed according to the teeth described above. Alternatively, it can be provided that only a subset of the teeth are formed according to the type described above. This allows the lid assembly to have teeth of different geometries, so that the assembly carrier can have at least two assembly groups.

[0020] The garment carrier can be manufactured or designed with a top layer made of or comprising a polymer and an adjoining underlayer, with a plurality of alternating felt and reinforcement layers arranged one above the other, wherein the felt and reinforcement layers of the underlayer can comprise fibers made of or comprising polyester.

[0021] The invention modifies both the foundation, i.e., the tooth holder in which the teeth are mounted, and the tooth geometry, so that the tooth length can only decrease, not increase, under bending stress. It has been shown that when the teeth are mounted in the redesigned tooth holder, the bending stress can be reduced even further. This is because the top layer provides excellent support for each individual tooth and absorbs the bending stress particularly effectively. Furthermore, the material used in the bottom layer (polyester) reduces the risk of tooth corrosion. This results in a bonus effect, and the invention is based on a single general inventive concept.

[0022] When, according to the invention, something is described as being viewed in a side view, this refers to the viewing direction that runs parallel to the axis of rotation of the carding drum. The carding carrier can be designed such that the top layer forms the outside of the carding carrier, which, when installed in a carding drum, faces the drum, and a felt layer on the underside forms the inside of the carding carrier.

[0023] Preferably, the polymer of the top layer can be a homopolymer, such as natural rubber, or a copolymer, such as styrene-butadiene rubber, nitrile rubber, or butyl rubber. The polymer used allows the restoration backing to be both particularly flexible and exceptionally well-suited to absorbing the bending forces exerted by the teeth. The top layer can be made entirely of the aforementioned polymer, i.e., from solid material.

[0024] A further improvement is achieved by each tooth bending around two bending points under load, the first bending point being located within the cover set between the top felt layer and the cover layer, and the second bending point being formed by the offset.

[0025] According to one embodiment, the reinforcing layers can be designed as planar textile structures, such as woven, knitted, crocheted, or braided fabrics. In this way, cost-effective reinforcement can be achieved.

[0026] The basis weight of a felt and reinforcement layer can advantageously be between 900 and 1400 g / m². 2 , preferably between 1200 and 1300 g / m² 2 This allows the teeth to be held particularly well in the respective felt and reinforcing layers of the underlayer.

[0027] Furthermore, the mounting bracket can also include a classic standard foundation. In particular, the mounting bracket can have a multi-layered flexible support structure made of fiber-based layers and an elastomeric top layer arranged on the support structure. The support structure can consist of several layers bonded together, with the bond being achieved by adhesives, thermal processes, mechanical fixing, or a combination of these techniques. The individual layers can comprise textile or fiber-based materials, in particular woven, knitted, or composite materials. The fibers can be of natural origin, such as cotton or linen, or synthetic, such as polyester, polyamide, or fiberglass. A top layer, consisting of or comprising an elastomeric or polymer-based material, can be arranged on the support structure.The top layer can be made of rubber, thermoplastic elastomers, polyurethane, or similar flexible materials and can have a smooth or textured surface. The base layer can also contain reinforcing elements to increase dimensional stability and may have a coating or impregnation to improve moisture resistance or reduce friction. Optionally, antistatic or thermally conductive layers can be integrated. The thickness of the individual layers and the top layer can vary to meet different flexibility and stability requirements. The base layer can be in strip form or as a continuous band.

[0028] It can be said that all cover sets or their set carriers are designed to be electrically conductive in order to be able to detect contacts between the tips of the teeth and the tips of a drum set of the carding machine, as is known per se.

[0029] Further measures improving the invention are described in more detail below, together with a description of a preferred embodiment of the invention, with reference to the figures. The figures show:

[0030] Fig. 1 a schematic side view of a teasel;

[0031] Fig. 2 Cover bars of a traveling cover in a detail view from Fig. 1;

[0032] Fig. 3 shows a longitudinal section through a section of a fitting carrier according to the prior art;

[0033] Fig. 4 shows a tooth in a side view;

[0034] Fig. 5 shows the structure and sequence of the manufacture of the garment carrier;

[0035] Fig. 6 shows a section through a furniture carrier;

[0036] Fig. 7 shows a representation of the cover fitting with the fitting carrier and a double cranked tooth.

[0037] Fig. 1 shows a highly schematic and therefore not-to-scale side view of a carding machine, comprising a feeding roller 1, feeding table 2, pre-tearers 3a, 3b, 3c, drum 4, take-up roller 5, stripping roller 6, crushing rollers 7, 8, fleece guide element 9, feed hopper 10, take-off rollers 11, 12, traveling cover 13 with cover deflection rollers 13a, 13b and cover bars 14, can 18 and can holder 19. The directions of rotation of the rollers are indicated by curved arrows. M denotes the center point (longitudinal axis) of the drum 4. 4a indicates the drum assembly and 4b indicates the direction of rotation of the drum 4. Arrow A indicates the working direction. Arrow B indicates the direction of travel of the cover bars 14 in carding position, and arrow C indicates the return transport of the cover bars 14. The curved arrows drawn in the rollers indicate the directions of rotation of the rollers.

[0038] Fig. 2 shows a detailed view of the object of Fig. 1, in particular the traveling cover 13. The cover bars 14 each have a cover head at both ends. Support bodies 15 are attached to the cover heads. The cover assembly 16 is attached to the underside of the support body 15. The distance between the cover assemblies 16 and the drum assembly 4a can be adjusted by means of an adjustable wedge strip 20. The tip circle of the narrowest point of each cover assembly 16 is designated by 21. The drum 4 has the drum assembly 4a, e.g., a sawtooth assembly, on its circumference. The tip circle of the drum assembly 4a is designated by 22. The distance between the tip circle 21 and the tip circle 22 is designated by a and is, for example, 0.20 mm. The distance between the convex outer surface 20a of the wedge strip 20 and the tip circle 22 is denoted by b.The radius of the convex outer surface 20a is denoted by r1, and the radius of the tip circle 22 is denoted by r2. The radii r1 and r2 intersect at the center M (see Fig. 1) of the drum 4.

[0039] Fig. 3 shows a longitudinal section through a portion of a fitting carrier 16a according to the prior art, as it could be used in the cover fitting 16 of the object of Fig. 2. The fitting carrier 16' shown in Fig. 3 comprises three layers 23, 24, 25, which are arranged one above the other and connected to each other. Between a lower layer

[0040] A middle layer 25 is located between a base layer 23 and a top layer 24. A thin coating (lacquer) is applied to the top layer 24. Two thin reinforcing layers 27a and 27b are arranged parallel to each other, i.e., one above the other, in the base layer 23. It is possible to produce the layers 23, 24, and 25 with various thicknesses to adapt them to specific requirements.

[0041] A multitude of trim wires, here referred to as teeth 16b, are inserted and anchored in the trim carrier 16'. The teeth 16b pierce the entire trim carrier 16' from the rear, with the free ends (tips) protruding from the cover layer.

[0042] 24 tower above.

[0043] Starting from the prior art shown in Figs. 1 to 3, the subject matter according to an embodiment of the invention will now be described with reference to Figs. 4 to 7.

[0044] Fig. 4 shows a side view of a tooth 16b with a preferred tooth geometry. The tooth 16b is simply offset along its entire tooth height ZH from the tooth root 16c to the tooth tip 16d. The tooth height ZH is defined as the vertical extent of the tooth 16b from the tooth root 16c to the tooth tip 16d. The upper tooth length OZL extends parallel to the upper tooth section from the offset 16e to the tooth tip 16d. The lower tooth length UZL extends parallel to the lower tooth section from the tooth root 16c to the offset 16e. Due to the bending angle BW between the lower and upper tooth sections at the offset 16e, the sum of the lower tooth length UZL and the upper tooth length OZL is greater than the tooth height ZH. The term "Krögenungen 16e" refers to a bend or curvature that forms a bending angle BW between the lower tooth length UZL and the upper tooth length OZL.The working angle AW is formed by a vertical line and the curved inner surface of the upper tooth length OZL at the tooth tip 16d and is preferably between 12 and 20 degrees. With this geometry, a breast angle BrW of 70 to 78 degrees results between the top surface of the cover assembly 16 and the inner surface of the upper tooth length OZL. Tooth 16b has an increased lower tooth length UZL for the same tooth height ZH, consequently shortening the upper tooth length OZL. This changes the ratio of lower tooth length UZL to tooth height ZH to 72% to 85%, preferably 73% to 76%. With a tooth height ZH of 7.5 mm, the lower tooth length is at least 5.4 mm, preferably at least 5.5 mm. Simultaneously, the plunge angle EW is reduced to 65 to 70 degrees. This results in two modified bending points, as can be seen in Figure 7.The first bending point 17 for tooth 16b lies within the cover assembly 16, specifically between the uppermost felt layer 23a and the polymer cover layer 24, which serves as an abutment. The second bending point is formed by the offset 16e. As a result, tooth 16b bends around two points 17 and 16e in such a way that an increase in the tooth height ZH is prevented.

[0045] Changing the mandibular length (UZL) and maxillary length (OZL) and altering the insertion angle (EW) offers the further advantage that the working angle (AW) at the unloaded tooth tip 16d is reduced to 12 to 20 degrees, preferably to 15 to 17 degrees. This reduction in the working angle (AW) results in less aggressive carding, which is further enhanced by the altered curvature of tooth 16b under load during carding. Consequently, the teeth have a longer service life.

[0046] Figures 5 and 6 show the structure and sequence of the manufacture of the furniture carrier 16a, as well as a section through a furniture carrier 16a according to an embodiment of the invention, analogous to Figure 3. Figure 5 shows the manufacture of the furniture carrier 16a with the layering according to the individual manufacturing steps. Figure 6 shows the finished furniture carrier 16a.

[0047] The trim carrier 16a is made here from a top layer 24 and a bottom layer 23. The bottom layer 23 is in turn made from a series of alternating layers of felt 23a and reinforcing layers 23b. In this embodiment, the felt layers 23a consist of polyester fibers processed into a felt. The reinforcing layers 23b, in this embodiment, consist of polyester fibers processed into a woven fabric.

[0048] To manufacture the trim carrier 16b, the process begins with the base layer 23. In step 1, 30, a reinforcing layer 23b and a felt layer 23a are prepared. This reinforcing felt layer is then needled to create a reinforcing felt layer. In step 2, 31, three of these needled reinforcing felt layers are prepared and needled together. Optionally, another felt layer 23a can be placed under the bottommost reinforcing layer 23b (step 32) and needled together in step 2. The resulting needled base layer 23 can optionally be heat-set. This results in an alternating layering of the base layer 23 consisting of several felt layers 23a and several reinforcing layers 23b, as shown in Fig. 6. Next, a top layer 24 made of a polymer is applied to the base layer 23 (step 33), e.g. by calendering.

[0049] The preferred tooth 16b shown in Figs. 4 and 7 can be incorporated into a tooth carrier 16a according to an embodiment of the invention, analogous to Fig. 3, such that the first bending point 17 is located within the cover assembly 16, specifically between the uppermost felt layer 23a and the polymer cover layer 24. The second bending point, the offset 16e, is located outside the cover assembly 16. The advantage of this arrangement is as follows: If the individual tooth 16b experiences a bending force F during operation of the carding machine – indicated by the thick arrow in Fig. 4 – the tooth 16b, or the individual sections, can "deviate" around both bending points 16e and 17, i.e., bend around them. This provides two pivot points around which the tooth 16b, and in particular the tooth tip 16d, can deform elastically. However, this causes the tooth tip 16d to move radially inwards from its initial position indicated in Fig. 4, i.e. in the direction of the cover layer 24.Because tooth 16b is also inserted in the drum carrier 16a, the tooth tip 16d does not move radially outwards. Therefore, it cannot elongate outwards due to the bending force F, which also prevents a collision with the drum drum 4a when tooth 16b bends. According to the prior art, the reinforcing layers 27a, 27b are often designed as sheet-like textile structures, such as woven, knitted, or braided fabrics, which allows them to securely hold the tooth base 16c. Since the reinforcing layers 23b and the felt layers 23a are made of polyester fibers, they absorb less moisture compared to cotton, thus reducing rusting of the teeth 16b during operation of the carding machine. Reference numeral.

[0050] 1 feed roller

[0051] 2 Dining table

[0052] 3a, 3b, 3c Tear-off

[0053] 4 drums

[0054] 4a Drum set

[0055] 4b Direction of rotation

[0056] 5 customers

[0057] 6. Scraper roller

[0058] 7, 8 crushing rollers

[0059] 9 fleece guiding element

[0060] 10 funnels

[0061] 11, 12 take-off rollers

[0062] 13 traveling lids

[0063] 13a, 13b Lid deflection rollers

[0064] 14 lid rod

[0065] 15 load-bearing bodies

[0066] 16 lid set

[0067] 16a Set carrier

[0068] 16b tooth

[0069] 16c Tooth base

[0070] 16d Tooth tip

[0071] 16th bend

[0072] 17 Bending point

[0073] 18 cans

[0074] 19 canning sticks

[0075] 20 wedge strip

[0076] 20a Outdoor area

[0077] 21 Top Circle

[0078] 22 Top Circle

[0079] 23 lower class

[0080] 23a Felt layer

[0081] 23b Reinforcing layer

[0082] 24 Top layer

[0083] 25 middle class

[0084] 27a, 27b Reinforcing layer

[0085] 30, 31, 32, 33 Step a Distance b Distance r1 Radius r2 Radius

[0086] A working direction

[0087] B Direction of travel

[0088] C Return transport F Bending force M Center point OZL Upper tooth length UZL Lower tooth length ZH Tooth height AW Working angle BW Bending angle BrW Breast angle EW Plunge angle

Claims

Patent claims 1. Tooth for a set carrier (16a) of a cover rod (16) of a carding machine, wherein the tooth is simply cranked along its length from the tooth base (16c) to the tooth tip (16d), wherein the tooth (16b) has a lower tooth section and an upper tooth section which are connected to each other by a crank (16e), and the ratio of the lower tooth length (UZL) to the tooth height (ZH) is 72% to 85%, preferably 73% to 76%.

2. Tooth according to claim 1, characterized in that the tooth (16b) is inserted at an insertion angle (EW) in the attachment carrier (16a), wherein the insertion angle (EW) of the tooth (16b) on its outer side to the attachment carrier is 65 degrees to 70 degrees.

3. Tooth according to one of claims 1 or 2, characterized in that the lower tooth length (UZL) is at least 5.4 mm, preferably at least 5.5 mm.

4. Tooth according to one of claims 1 to 3, characterized in that the upper tooth length (OZL) is 2.3 mm to 2.5 mm.

5. Tooth according to one of claims 1 to 4, characterized in that the working angle (AW) is formed by a vertical line and the curved inner side of the upper tooth length (OZL) at the tooth tip (16d) and is between 12 degrees and 20 degrees.

6. Tooth according to one of claims 1 to 5, characterized by a breast angle (BrW) of 70 degrees to 78 degrees between the top of the cover assembly and the inside of the upper tooth length.

7. Tooth according to claim 6, characterized in that the ratio of insertion angle (EW) to breast angle (BrW) is 83% to 100%.

8. Tooth according to one of the preceding claims, characterized in that the tooth has a contour, in particular a side bevel and / or back bevel.

9. Tooth according to claim 8, characterized in that the contouring is formed only in the upper tooth section, or that the contouring is formed in the upper tooth section and beyond the crank (16e) in the lower tooth section.

10. Cover fitting (16) for a cover rod (14) of a teasel, comprising a fitting carrier (16a) with teeth (16b), characterized in that at least a subset of the teeth (16b) are designed according to one of claims 1 to 9.

11. Lid assembly (16) according to claim 10, characterized in that the assembly carrier (16a) is formed with a top layer (24) made of or comprising a polymer and an adjoining underlayer (23) with a plurality of alternately arranged felt and reinforcement layers (23a, 23b), wherein the felt and reinforcement layers (23a, 23b) of the underlayer (23) comprise fibers made of or comprising polyester.

12. Lid assembly (16) according to claim 11, characterized in that the polymer of the cover layer (24) is a homopolymer, such as natural rubber or a copolymer, such as styrene-butadiene rubber, nitrile rubber or butyl rubber.

13. Lid set (16) according to claim 11 or 12, characterized in that the reinforcing layers (23b) are designed as planar textile structures, such as woven, knitted, crocheted or braided fabrics.

14. Cover assembly (16) according to one of claims 11 to 13, characterized in that the assembly carrier (16a) is designed such that the cover layer (24) forms an outer side of the assembly carrier (16a), which in the installed state is facing a drum (4) of the carding machine, and a felt layer (23a) of the underside of the assembly carrier (16a) forms an inner side of the assembly carrier (16a).

15. Lid fitting (16) according to one of claims 11 to 14, characterized in that the basis weight of a felt and reinforcement layer (23a, 23b) is between 900 and 1400 g / m² 2 preferably between 1200 and 1300 g / m² 2 amounts.

16. Lid assembly (16) according to claim 10, characterized in that the assembly carrier (16a) has a multi-layered flexible carrier structure made of fiber-based layers and an elastomeric cover layer arranged on the carrier structure.

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