EP0620295A1 - Bend as a sliding guide for a travelling, flat carding machine - Google Patents

Abstract

A flexible bow (70) forms a sliding guide for the bars of the flat in their working position. The bow is designed as a wearing element. If the bow is formed from a plurality of elements, they can be mounted or adjusted jointly in the card. <IMAGE>

Description

This invention relates to the sliding guide which is provided in the revolving flat card for guiding the flat bars in their working positions.

State of the art

• eine dünne Metallplatte
• eine Sinterbronzeschicht
• eine Schicht aus Polyacetalharz mit einem Schmiermittel

The closest prior art is JP-A-55-172377 (published December 10, 1980), according to which a multi-layer structure is built on the flexible sheet of a card. The layers include:

• a thin metal plate
• a layer of sintered bronze
• a layer of polyacetal resin with a lubricant

Further proposals are contained in DE-A-3907396 and DE-A-4108921, according to which the sliding surface on the arch is formed by a plastic element which has to be mounted and fastened on the arch.

From CH-A-681017 it is known to coat the sheet in order to reduce wear on the sheet. However, this only leads to wear of the gliders of the flat bars.

The invention, aspect 1

The invention in its first aspect provides a flexible arch for a revolving flat card, characterized in that the arch consists of a carrier and a flat rod sliding guide, the carrier and the guide being connected to one another in such a way that after the connection can be reworked or adjusted together to determine the accuracy of the sliding surface.

The invention, aspect 2

The invention in its second aspect provides a revolving flat card with a flexible arch for guiding the cover bars as they run through the work area, characterized in that the part of the arch contacting the flat bars is formed from a material which is different from the material of the parts touching it Decorative bars have good sliding properties with a relatively low wear resistance, so that the wear that is inevitable due to the sliding of the flat bars takes place on the sheet for the most part.

The flexible sheet according to aspect 1 and / or aspect 2 can be formed from plastic, for example from a fiber-reinforced plastic. However, the sliding surface (which contacts the flat bars) preferably does not contain any reinforcing agents, since the material forming this surface should be selected specifically for its sliding properties.

The flexible sheet can therefore comprise a carrier made of another material, for example made of metal.

The bow should definitely be cheap to manufacture so that it can be replaced inexpensively.

The application of the flat bars to a plastic element should be achieved without stress peaks in the plastic and preferably without special formation of the flat bars themselves. This can be done, for example, by providing an inlet element which is located on the plastic element connects. However, the guiding of the flat bars can be so precise that the desired effect is achieved both without special design of the flat bars and without an additional guide element.

Embodiments of the invention are now explained in more detail with reference to the figures as examples:

Fig. 1

eine Ansicht einer Wanderdeckelkarde, die beispielsweise nach DE-A-3835776 gebildet ist,

Fig. 2

einen Plan der gleichen Karde in Obenansicht, ohne den Wanderdeckelsatz,

Fig. 3

ein Detail des Wanderdeckelsatzes dieser Karde,

Fig. 4

einen Flexibelbogen gemäss einer neulich eingereichten schweizerischen Patentanmeldung (Obj.2378)

Fig. 5

im Querschnitt ein Detail des Flexibelbogens der Karde nach Figur 4,

Fig. 6

ein Detail der Einlaufstelle der Deckelstäbe am Kunststoffelement nach Fig. 5,

Fig. 7

ein Einlaufelement zur Verwendung an der Einlaufstelle nach Fig. 6,

Fig. 8

eine Seitenansicht eines Flexibelbogens nach dieser Erfindung,

Fig. 9

eine Ansicht der Stirnfläche des Bogens,

Fig. 10

eine Ansicht ähnlich Figur 9 einer zweiten Ausführung, und

Fig. 11

ein Perspektivbild eines Teils einer Schicht zur Verwendung in der Ausführung nach Figur 10.

It shows:

Fig. 1

2 shows a view of a revolving flat card, which is formed, for example, according to DE-A-3835776,

Fig. 2

a plan of the same card in top view, without the revolving cover set,

Fig. 3

a detail of the set of revolving lids of this card,

Fig. 4

a flexible sheet according to a recently filed Swiss patent application (Obj. 2378)

Fig. 5

in cross section a detail of the flexible bow of the card according to FIG. 4,

Fig. 6

5 shows a detail of the entry point of the flat bars on the plastic element according to FIG. 5,

Fig. 7

6 an inlet element for use at the inlet point according to FIG. 6,

Fig. 8

a side view of a flexible sheet according to this invention,

Fig. 9

a view of the face of the arch,

Fig. 10

a view similar to Figure 9 of a second embodiment, and

Fig. 11

10 shows a perspective image of part of a layer for use in the embodiment according to FIG. 10.

Arrangements to the prior art are described in more detail in FIGS. 1 to 6 in order to better understand the present invention.

Figure 1 shows a revolving flat card according to DE-A-3835776 with a frame 10, briseur 16, reel 17, pickup 21 and revolving flat set 19. The revolving flat set 19 comprises one hundred and six flat rods 29, of which forty-one are in the working position, two endless traction means 28 (e.g. Chains or toothed belts), of which only one such means is visible in FIG. 1, and four pairs of deflection wheels 22, 23, 24, 25, of which only one wheel of each pair is visible in FIG. 1. The wheels of the pair 25 are driven to move the traction means in the direction of the arrow 30. The traction means or their respective wheels form two movement paths in a vertical plane. The reference numerals 41 to 49 indicate a modular division of the outer surface of the drum according to DE-A-3835776. This division is of no importance for the present invention and is not explained in more detail.

Each flat bar 29 is fastened at one end to one and at the other end to the other traction means 28 and is at right angles to both. The rods 29 are therefore moved along the paths during operation when the traction means 28 are moved along their own lengths by rotating the deflection wheels 25. The rods 29 are fastened to the traction means 28 in such a way that the fastening means (not shown) must be loosened in order to remove the rod from the traction means. Various such fasteners are known and are not explained in detail here.

The machine frame 10 comprises two side plates 32 (FIG. 2) (side walls), which receive the bearing axis 31 for the rotatable drum 17 and carry support parts 27 (FIG. 1) for the cover set 19. The side shields are shown in FIG. 2 without details, but are explained in more detail below with reference to FIG. 4.

The preferred flat bar conveyor system generally corresponds to the arrangement according to FIG. 1 of DE-C-1115621, which is shown in FIG. 3 of this application. The deflection rollers 22, 23 (only roller 23 shown in FIG. 3) are formed with teeth 20. The flat bars 29 are fastened at their two ends to a flexible band 28A (e.g. a toothed belt) by means of clamping devices 29A. The clamping devices 29A are formed as teeth that match the gear wheels 22, 23. When leaving the gear 23 at the entry point E (FIG. 1), a flat bar is placed against a sliding guide surface 52 (FIG. 3), the belt path being tensioned between the wheels 22, 23 in order to press the flat bars against the sliding guide surface 52. This flat bar conveyor system is not absolutely necessary, but is taken as an example in the explanations below. Smaller changes in the clamping devices are explained below with reference to FIG. 4.

The outer surface of the drum 17 is provided with a set, the surfaces of the flat bars 29, which are directed outwards from the cover set 19, likewise. A substantial part of the carding work is carried out between a cover rod and the reel, while the rod extends from the entry point E (FIG. 1) to an exit point A moved, this movement can take place in the same direction as the rotation of the drum (in the same direction) or (as shown in FIG. 1) opposite the drum movement (in opposite directions).

During the movement between the entry and the exit point, the flat rod (or its clothing) must maintain a precise distance from the drum. This distance is not determined by the cover set 19 itself, but by the aforementioned slide guides 52, which are provided on the upwardly facing surfaces of the side walls 32. Each slide guide can be formed (and even adjusted) exactly in relation to the axis of rotation of the drum, as will now be explained with reference to FIG. 4.

In practice, each sliding guide is formed on a respective flexible arch 34. The bow 34 has lugs 35 which are mounted on the respective side plate 32 by means of adjustable fastenings (not shown). By adjusting the fastenings, the flexible sheet 34 can be curved more or less with respect to the axis of rotation of the drum 17 in order to influence the design of the sliding guide with respect to the drum. According to the above-mentioned prior art, each flexible sheet is provided with a plastic element which forms the actual sliding guide, this element being guided around the deflection wheels 22, 23.

According to the aforementioned Swiss patent application (Obj. 2378), a plastic element 50 (for example a plastic strip) is attached to the flexible sheet 34 mounted and set in the card in such a way that it forms the sliding surface 52 for the flat bars 29. 5, the plastic element is in the form of a plastic strip, which is inserted in a groove 51 in the upward surface of the sheet 34 is. The thickness of the strip is greater than the depth of the groove, so that the strip protrudes from the groove. The protruding part of the strip (or the surface facing upwards thereof) forms the aforementioned sliding surface for the flat bars. The element 50 extends along the arc 34 away from a fastening 54 which lies outside the region G (FIG. 1) which is covered by the flat bars 29. This attachment 54 is located in front of the entry point E (viewed in the direction of movement of the flat bars).

Each flat bar 29 is provided at each end with a "flat head" which includes both a slider 29B and the aforementioned clamping device 29A. The slider 29B is formed in one piece with the working body of the rod 29, while the clamping device 29A comprises a first part, which is formed in one piece with the slider, and a second removable clamping part. The clamping part is fastened to the first part by a screw 27 (FIG. 4), the belt 28A being clamped between the first and the second part.

The sliders 29B of the flat bars 29 in their working positions sit snugly on the plastic element 50, so that the distance between the lid set and the drum set is determined by the position of the plastic element 50 relative to the flexible sheet 34. The flat bars 29 therefore exert tensile forces on the plastic element 50 in the direction of the flat bar movement 30. It is therefore only necessary to also fasten the plastic element 50 at its end remote from the fastening 54 if the direction of movement of the flat bars 29 must be expected to be reversed. Preferably no second attachment is provided outside the working area G of the flat bars 29, because such an additional attachment is only possible Faults could result if the element 50 elongates during operation.

The sliders 29B are normally provided with two sliding surfaces 56, 58 (FIG. 4), which each make up about 1/3 of the width of the cover rod and therefore sit snugly on the curved sliding surface 52 of the plastic element 50 when the flat rod 29 is opposite the Flexible arch 34 has taken up its working position. The flat rod sliding surfaces 56, 58 are normally ground at right angles to the two side surfaces 60 of the slider, which leaves an edge K at the transition between these surfaces. This edge K can lead to problems at the entry point E, as will now be explained with reference to FIG.

• der Krümmung des Bogens 34,
• dem Krümmungsradius des Umlenkrades 22 bzw. 23,
• der Stellung des Umlenkrades 22 bzw. 23 gegenüber dem Bogen 34.

The angular position of a flat bar 29 with respect to the arc when it approaches the plastic element 50 at the entry point E depends on some parameters, for example:

• the curvature of the arc 34,
• the radius of curvature of the deflection wheel 22 or 23,
• the position of the deflection wheel 22 or 23 relative to the arc 34.

In order to avoid load peaks in the plastic element 50 at the entry point E, the sliding surfaces 56, 58 of the flat bars 29 should move approximately in a tangential direction with respect to the curved element 50 during the entry. If this is not the case, either the front or the rear edge K of the flat rod sliding surfaces as the first part of the rod 29 will touch the plastic element 50 and result in a strong scraping effect (if not a "peeling").

• die Umlenkrolle 23
• den Riemen 28A

und die Träger 27 (Fig. 1) für die Rollen 23.In principle, it is possible, at least in principle, to avoid such peak loads simply by adjusting the elements involved. However, this will prove to be difficult in practice, both with regard to the implementation and with respect to the desired settings.
In this case, the essential elements of the flat bar guide must be mounted very precisely in relation to the flexible bend 34. In the variant according to FIG. 6, these essential elements include

• the pulley 23
• the strap 28A

and the carriers 27 (FIG. 1) for the rollers 23.

Another possibility is to form the edges K of the flat bars 29 in such a way that they do not trigger any damaging effects, even if the sliding surfaces 56, 58 of the flat bars do not move exactly tangentially with respect to the plastic element 50 when they run in. However, this makes the production of the flat bars 29 more expensive, in particular because this measure is not necessary for flexible sheets 34 without plastic sliding surfaces.

A suitable practical and hitherto unknown solution is shown in FIG. 7 and consists in providing an inlet element 62 which is located in the “wedge gap” between the inlet slider of the flat bars 29 and the plastic element 50. The inlet element 62 has an inlet surface 63 which adjoins the sliding surface 52 of the plastic element 50 approximately tangentially. Any unsuitable angular positions of the flat bars 29 can therefore be corrected by contact with the inlet element 62 before the first contact with the plastic element 50. Since the inlet element 62 before actual entry point E, it does not matter that the position of the cover rod on the entry element 62 relative to the drum 17 is not ideal. For the same reason, wear marks on element 62 are of secondary importance.

The main teaching of the previous proposals aims to precisely design a guide element (the arch) in the card and to provide this element with a precisely manufactured "covering" (coating, cover, protective layer). The idea was either to avoid wear on the guide element (hard coating, see CH-A-681017) or to compensate for this wear with an easily replaceable element (Fig. 4 to 6).

• 1. der Verschleiss sollte sich an der Deckelstabführung und nicht an den Deckelstäben auswirken,
• 2. das Vorsehen der voreingestellten Deckelstabführung mit einem austauschbaren Schutzelement, welches den Verschleiss auffängt, führt im Zusammenhang mit der Befestigung zu Problemen,
• 3. die Deckelstabführung muss daher entweder selbst leicht (kostengünstig) austauschbar sein oder sie muss eine kostengünstige Nachbearbeitung bzw. Nacheinstellung ermöglichen.

This invention is based on the following findings:

• 1. the wear should affect the flat bar guide and not the flat bars,
• 2. the provision of the preset flat rod guide with an exchangeable protective element, which absorbs the wear, leads to problems in connection with the fastening,
• 3. The flat rod guide must therefore either itself be easily (inexpensively) exchangeable or it must enable inexpensive post-processing or readjustment.

FIG. 8 shows a flexible sheet 70 in side view, which comprises a carrier 72 and a sliding guide 74. The slide guide 74 consists of a thick plastic layer which is connected to the carrier 72 by means of a dovetail connection 76 (FIG. 9). The carrier 72 can be made of metal formed, but could be made of fiber reinforced plastic. The connection must be designed in such a way that the thick layer 74 follows adjustment movements of the carrier 72 without being deformed in the process.

The type of connection shown in Fig. 9 is not essential to the invention. The connection can also be effected, for example, using an adhesive. The connection has in any case been carried out in such a way that the flexible bend 70 can be mounted and adjusted as a unit in the card. In practice, a sliding guide or layer 74 has proven itself, which consists of a fluoropolymer (PTFE) with special organic fillers to increase the pressure and wear resistance. Such a fluoropolymer is known under the registered trademark RULON by the FURON Company. The thickness of the layer is below 0.1 mm, preferably 0.05 mm. Another suitable material based on PTFE is TURCITE-B (brand name) from Busak + Luyken GmbH & Co., D-Stuttgart, whereby the same layer thickness is also used here. This layer is then glued to the carrier 72 with suitable adhesives, such as with the ARALDIT adhesive (brand name) from Ciba-Geigy AG, CH-Basel. The aforementioned materials can also be reworked very well with very small layer thicknesses and have led to good results.

After this bow no longer fulfills its function properly due to wear, it can only be made usable again by readjusting it or by grinding the sliding surface together with a readjustment. If this is no longer possible, it must be replaced as a unit.

10 shows a further variant of this invention, according to which the sliding surface is not formed by plastic (or at least not by plastic alone). The design of the arch 80 comprises a carrier 82 and a sliding guide layer 84. The sliding guide layer is fastened to the carrier by means of screws 86, 88, for example.

The screws 86, 88 are connected to current conductors 90, for example, which indicate when the wear on the sliding guide exceeds a predetermined level by short-circuiting the current conductors by contact with a flat bar.

The layer 84 consists, for example, of a metal matrix 92 with holes 94 which contain a plastic or a lubricant (FIG. 11). The layer could also be made from sintered bronze (a bearing alloy).

Another variant of this invention would be to produce the arch itself from plastic, so that the arch does not have to be composed of two elements. However, it is unlikely that a single material can have both the necessary strength (fatigue resistance) and the required sliding properties. This can be achieved in that reinforcing means are provided in the lower part of the arch in order to provide the necessary strength here by forming a composite material.

Claims (7)

Flexible arch for a revolving flat card, characterized in that the arch (78; 80) consists of a carrier (72; 82) and a flat rod sliding guide (74; 84), the carrier (72; 82) and the guide (74; 84) in this way are connected to each other so that after connection they can be reworked or adjusted together to determine the accuracy of the sliding surface. Revolving flat card with a flexible sheet for guiding the flat bars during their run through the work area, characterized in that the part of the sheet (70; 80) touching the flat bars is formed from a material which has good sliding properties compared to the material of the parts of the flat bars touching it has relatively low wear resistance, so that the wear and tear that inevitably occurs due to the sliding of the flat bars takes place on the sheet for the most part. Flexible sheet according to claim 1 or card according to claim 2, characterized in that the part of the sheet (70; 80) contacting the flat bars is made of plastic. Flexible sheet or card according to claim 3, characterized in that the part of the sheet (70; 80) contacting the flat bars is formed from a bearing alloy. A revolving flat card according to claim 3 or 4, characterized in that the flat bars (29) are fastened to the traction means (28) in such a way that the flat bars are attached to all points are conveyed by the traction means, the cover rod guide (22, 28A; 62) being designed at the entry point (E) where the flat bars are brought into contact with the sliding surface in such a way that no load peaks occur on the sliding surface. Card according to claim 5, characterized in that the flat bar guide (22, 28A; 62) at the entry point (E) is designed such that the contact surfaces (56, 58) of the flat bars (29) of the sliding surface are almost tangential in one direction Approach the curvature of the guide surface. Card according to one of the preceding claims 3 to 6, characterized in that an inlet element (62) is provided which has a guide surface (63) which adjoins the sliding surface.

Images