NL8600536A - Radial or axial bearing between fixed and rotating component - has mutual contact surface formed only by layer of fibres secured to one or other component, possibly to elastomer bush or ring - Google Patents

Abstract

The slide bearing between two relatively movable components such as a bearing mounting and a rotating shaft has a mutual contact surface of one of the components, e.g. formed by a layer of fibres only which are secured to that component. The mounting may contain an elastomer bush with the fibre layer secured to its inner wall surface or to the shaft portion facing that surface. The fibres may consist of aramide or cabron and the layer may be a woven, knitted or non-woven fabric. The fibres may be arranged to form a helical structure (in radial bearing) or a spiral structure (in axial bearing). The fibre layer may be secured by a resin, such as epoxy resin, only partly penetrated therein so that it does not itself form part of the contact surface. In an elastomer bush or on an elastomer ring, the layer may be secured by vulcanisation.

Description

s * NO 33698

Lower

The invention relates to a slide bearing between two parts movable relative to each other.

Such bearings are generally known and usually consist of a t * bearing metal-coated bush, which may or may not have lubricating grooves, which bush supports the shaft in the case of a radial bearing and consist of a disc, which cooperates with a ring of bearing metal, it is an axial bearing.

It is also known in both axial and radial bearings that rings or. using cans from a suitable plastic, for example a polyamide.

It is further known to design the bearing from an elastomeric material, the surface of the elastomeric sleeve resp. the elas-15 tomere ring cooperates with a shaft provided with a helically running groove resp. a disc provided with radial grooves. Examples of the latter type can be found in the Dutch patent applications 8002280 and 8002281, which have been laid open to inspection. The latter type is intended in particular for the mounting of propeller shafts in ships 20 and of pump shafts.

The aforementioned other known bearings have a soft metal as the lower metal. These layers are used, for example, to support a crankshaft in an engine.

All known bearings are based on the principle that during the rotation of the bearing parts relative to each other a lubricant wedge is formed between these parts, which can end up in a thin film of lubricant. This lubricant can be present in the bearing or be supplied via channels running in the bearing bracket or arranged in the shaft. The purpose of this film is to separate the parts moving relative to each other and because the lubricating film itself has a very low internal friction, the object is to limit the friction and therefore the heat development between the parts movable relative to each other. These known bearings are relatively fragile if the temperature rises too high at peak loads. The surfaces that move relative to each other can then chafe, which can lead to melting of the soft material. In bearings with elastomeric parts that cooperate with a grooved counter face, the grease wedge builds up earlier, which is favorable for the areas of application for which these bearings are intended, such as where water forms the lubricant 40. Water has poorer lubricating properties than oil.

The object of the invention is to provide a completely different bearing P '^ "α -v'

* '·' F J

ψ Τ '* r * ... · · ν 2 which has different and better properties adapted to the different application possibilities, ensures good lubrication and is very durable in all circumstances.

This object is primarily and in principle achieved in that the contact surface of the bearing on one of the two parts movable relative to each other is provided with a layer of fibers adhering to that part, and only the fibers form the bearing surface. The fiber layer thus forms the contact surface and this layer of fibers is less smooth compared to the supported member. Depending on the structure of the fiber layer, slightly raised and slightly lowered areas alternate on the surface of the fiber layer. The raised areas together form the support surface for the moving part, while the lowered areas form recesses for the lubricant. This ensures good lubrication, especially under boundary lubrication conditions.

According to a first embodiment of the invention, the bearing can be considered radial. bearing, the rotatable part of which is a shaft, which is supported in a sleeve of elastomeric material fixedly mounted in a bearing bracket. According to the invention, the internal surface of the sleeve is then provided with the layer of fibers.

Preferably, the fiber layer is adhered to the one part by means of an adhesive, such as a resin, which adhesive is only partially penetrated into the thickness of the fiber layer. When using elastomeric bearing parts, bonding by vulcanization is also possible.

As a variant, the radial bearing can be designed such that the layer of fibers is applied to the shaft at the location of the bearing bracket.

In this embodiment of the radial bearing, the fiber layer may consist of a wrap with continuous filaments or yarns, which are prayed in an adhesive such that the outer surface of the wrap 30 is free of adhesive.

If it concerns an axial bearing, in which one part consists of a wall parallel to a disc mounted on an axis, to which disc an elastomer ring is attached, this can be designed according to the invention such that on the side facing the wall the elastomeric ring is provided with a layer of fiber.

According to the invention, various high strength materials can be used for the fibers. Preferably aramid fibers are used, which not only have a high strength and wear resistance, but also a low coefficient of friction on metal. This 40 has the advantage that the heat development in a bearing with that:? · R -Λ "v 'v w v m' J -0 Ό 3 'material is further limited.

According to the invention, the fibers can also consist of carbon.

Preferably, before forming into a bearing, the fibers are assembled into a cohesive layer or web. According to the invention, this layer can be in the form of a fabric or knit, but also of a non-woven fabric. A fabric is preferred. Strips of the desired length can be taken from such layers, which are then applied to the bearing. Attachment to the bearing can be performed with an adhesive, such as epoxy resin, and in the case of an elastomer sleeve bearing, the strip can be attached by vulcanization. The abutting ends of the strip are correspondingly shaped such that they fit exactly together. In the case of a fabric, for example, these ends preferably run according to the warp and / or the weft, i.e. along a line which is inclined to the relative direction of movement. In the case of knitting, the fibers can also be assembled into a cylinder, from which an annular web is taken, which can be applied to the bearing.

Instead of assembling the fibers into a web as before, for a radial bearing, a yarn or a bundle of continuous element threads can be applied to the shaft as a helix with abutting turns.

With an axial bearing, a spiral winding with adjacent windings is conceivable.

Usually, however, preference will be given to a fiber layer with intersecting fibers, as is the case with a fabric, because then depending on the chosen denier of the yarn, more or less pronounced tops and valleys are formed, which do not disturb it by adhesive somewhat open contact surface, which appears to be able to immediately and properly form a lubricating wedge film regardless of the type of lubricant, while the aramide or carbon fibers, when used, also prove to be insensitive to temporary dry running.

The invention will be further elucidated hereinbelow on the basis of some exemplary embodiments shown in the drawings.

FIG. 1 shows a longitudinal section of a radial bearing according to the invention.

Fig. 2 shows a longitudinal section of an axial bearing according to the invention.

In Fig. 1, a fixed member 1, for example a bearing bracket, is provided with a elastomeric sleeve 2 fixedly fixed therein and provided internally with a fiber layer 3 adhered therein. The fibers can run in any direction; as an example, two fiber directions for a fabric composition are sheared from the fibers. A shaft 4 rotatably rests on the fiber layer. If desired, this shaft can be provided in known manner with a helical groove (not shown). The starting properties of such a per se known elastomer lower are not adversely affected by the fibrous layer.

In Fig. 2, a rotatable member 5 in the form of a disc is provided with a elastomeric ring 6 fixedly attached thereto. It is provided on the side facing the fixed flange 7 with a layer of fibers 8, which fibers can be positioned in any direction. expired. Here too, the disc can be provided with grooves in a known manner.

However, the invention also applies where the fiber layer is adhered to metal, for example by using a metal sleeve or ring instead of an elastomeric sleeve or ring.

It is also conceivable that in the bearing of Fig. 1 the sleeve is a metal sleeve, for instance of brass, and the fiber layer consists of a wrapping of the shaft with the desired diameter, which wrapping can have adjacent turns or intersecting turns.

.-Λ, - * s *. - - O '_ .. - ·

Claims (14)

Plain bearing between two parts which can be moved relative to each other, characterized in that the contact surface of the bearing on one of the two parts which can be moved relative to each other is provided with a layer of fibers adhering to that part, and only the fibers bearing surface 5 shapes Radial bearing according to claim 1, wherein the rotatable part is a shaft supported in a sleeve of elastomeric material fixed in a bearing bracket, characterized in that the inner surface of the sleeve is provided with the layer of fibers. Radial bearing according to claim 1, wherein the rotatable part is a shaft supported in a bearing bracket, characterized in that the layer of fibers is applied to the shaft at the location of the bearing bracket. Axial bearing according to claim 1, wherein the one part consists of a wall parallel to a shaft mounted disc to which disc an elastomeric ring is attached, characterized in that on the side of the elastomeric ring facing the wall a layer of fiber has been applied » Bearing according to one or more of the preceding claims, characterized in that the fibers consist of armide. Bearing according to one or more of the preceding claims, characterized in that the fibers consist of carbon. Bearing according to one or more of the preceding claims, characterized in that the fibers form a fabric. 8. Bearing according to one or more of the preceding claims, characterized in that the fibers form a knit. Bearing according to one or more of the preceding claims, characterized in that the fibers form a non-woven fabric. Bearing according to any one of claims 1,2,3,5 or 6, characterized in that the fiber layer has a helical structure. Bearing according to one of claims 1, 4, 5 or 6, characterized in that the fiber layer has a spiral structure. 12. Bearing as claimed in one or more of the foregoing claims, characterized in that the fiber layer is adhered to the one part by means of an adhesive, such as a resin, which adhesive is only partially penetrated into the thickness of the fiber layer. Bearing according to any one of claims 1, 2 or 4 to 11, characterized in that the fiber layer is adhered to the elastomeric part by vulcanization. \ 40, v; 6 w * v Bearing according to claim 3, characterized in that the fiber layer consists of a wrapping with continuous filaments or yarns, which are prayed in an adhesive, such that the outer surface of the wrapping is free of adhesive. v j · £ 5