WO1982003665A1

WO1982003665A1 - Prefabricated lubricant unit

Info

Publication number: WO1982003665A1
Application number: PCT/SE1982/000134
Authority: WO
Inventors: Telefon Ab L M Ericsson
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-04-24
Filing date: 1982-04-23
Publication date: 1982-10-28
Anticipated expiration: 1983-10-24
Also published as: FI824201A0; DE3264541D1; NO149220B; US4480717A; EP0076836B1; JPS58500586A; CA1177414A; EP0076836A1; MX154826A; NO824289L; NO149220C; SE426092B; FI824201L; FI69191C; FI69191B; SE8102629L

Abstract

A prefabricated lubricant unit intended for insertion between two bodies (4, 6) during their displacement relative each other with the intention of reducing the friction between them, thereby replacing messy, manually applied lubricant. The lubricant unit includes two films, or one film (1, 2) folded double and a lubricant (3) placed in the space between them. After fulfilling its lubricating task, the lubricant unit can be removed without leaving traces in the form of grease, oil, soap or the like.

Description

PREFABRICATED LUBRICANT UNIT

TECHNICAL FIELD

The present invention relates to a lubricant unit to be applied between the contact surfaces of two bodies, for reducing the friction between them when they are displaced relative each other, especially in the case where one or both bodies comprise porous material.

BACKGROUND ART

In the mutual displacement of bodies it is a usual technique to apply between them some friction - reducing agent such as oil, grease, soap or the like. A disadvantage with the known technique is that the lubricant has a tendency to spread to such places where it is not supposed to be, at the same time as handling often becomes messy. When the operation which requires the lubricant has been executed, an extra cleaning operation is generally required, in v/hich a solvent of some kind must often be used, and workmen' s safety directions relating to air changes etc. must be observed. If one or both bodies is of porous material there is the additional drawback that the lubricant is absorbed by the porous material.

DISCLOSURE OF INVENTION

The object of the present invention is to provide a prefabricated lubricant unit v/hich may ne placed between bodies for their displacement relative each other, and which in appropriate cases, when it has served its purpose, can be removed without leaving any traces. There is thus eliminated messy work operations, at the same time as a guaranteed good lubricating effect is achieved.

The lubricant unit in accordance with the invention is characterized in that it includes in its unapplied condition at least one film arranged with mutually facing film surfaces and with a lubricant deposited between these surfaces. The contact surface of at least one of the bodies is covered by film after placing the lubricant unit between the bodies in question, and the force required for overcoming friction between the bodies will be dependent only on the friction between a film surface coated with lubricant and one contact surface or between two film surfaces coated with lubricant.

An advantageous application of the invention constitutes a lubricant unit for reducing the friction when inserting a hard body in a hole in an elastic material, where the hole has substantially less dimensions than those of the body. In such a case the hard body can constitute a sleeve used for laying cable through a fϊre-sealϊng lead-through filled with elastic material, the hole with the substan¬ tially lesser dimensions in this case being one for a cable made in the elastic material of the fire seal, said material usually constituting a silicon foamed rubber.

Preferred embodiments of the invention for precisely this purpose will be described in detail in the following while referring to the appended drawings.

DESCRIPTION OF FIGURES

Figure 1 illustrate in cross section a lubricant unit in the form of a hose or stocking. Figure 2 illustrates a sleeve with a lubricant stocking placed over it before insertion in a fire-sealed lead-through. The lubricant stocking and lead-through are illustrated in cross section.

Figure 3 illustrates the same sleeve with the lubricant stocking as in Figure 2, but after insertion in the lead-through. Figure 4 illustrates a lubricant stocking in cross section, with a slit outer hose, during a stage of manufacture.

Figure 5 illustrates the same lubricant stocking ready for use.

Figure 6 illustrates a lubricant stocking in cross section, with a lubricant pad inserted between the film layers, in the form of an intermediate layer impregnated with lubricant. PREFERRED EMBODIMENTS

Figure 1 is a cross section of a lubricant unit in the form of a hose or stocking. A tube of plastic film has a portion pulled over irself at one end, to form an inner tube 1 and an outer tube 2, partially overlapping the inner tube 1. A lubricant layer 3 has been uniformly applied between the inner and outer tubes.

In Figure 2 there is illustrated a sleeve 4, and in section there is shown a lubricant stocking pulled over it and comprising an inner tube 1, an outer tube 2, and between these two a layer of lubricant 3. The sleeve, which has a conical end portion 5, is illustrated in position for insertion in a hole 7, made in elastic material 6 filling a lead-through, also shown in cross section. The stocking has been pulled over the sleeve just sufficiently for the outer tube 2 to cover the conical portion of the sleeve.

Figure 3 illustrates the same sleeve as in Figure 2 but now thrust into the lead- through. The relatively large friction between the inner tube 1 of the lubricant stocking and the sleeve 4 as well as between the outer tube 2 and the elastic material 6, has resulted in that the inner tube 1 has adhered to the sleeve 4 and the outer tube 2 has adhered to the elastic material 6 when the sleeve was pushed in. The sleeve has thus glided into the lead-through on the surfaces of the lubricant stocking, facing each other and coated with lubricant, a further portion of the inner tube having been pulled inside out to become an outer tube. When the sleeve is pulled out from the hole after cable laying has been completed, the stocking is pulled back into its original shape.

Figure 4 illustrates a lubricant stocking in cross section, with a slit outer tube, during a stage in manufacture. If the outer tube is slit up along the whole of its length at two mutually opposing positions, the tube can be flattened in manufacture, the two outer tube havles 8 and 9 can be coated with lubricant, whereupon these can be folded towards the inner tube in a manner illustrated by the Figure. The appearance of the final product is apparent from Figure 5, which illustrates a cross section of a lubricant stocking manufactured in this manner. Figure 6 illustrates a lubricant stocking in cross section, with a lubricant pad 10 in the form of an intermediate layer impregnated with lubricant inserted between the inner tube 1 and outer tube 2. The layer may comprise blotting paper, thin cellular plastics or the like, which has been allowed to absorb the c necessary amount of lubricant. The pad is placed between the outer and inner tubes so that it is completely circumferential. This method substantially simplifies lubricant dosage and manufacture, while ensuring uniform lubricant distribution, When a lubricant stocking with a lubricant pad is used for inserting a sleeve in a fire-sealing lead-through in a manner previously illustrated in Figures 2 and 3, there will be first a compression of the lubricant pad, resulting in that lubricant is pressed out into the space between the outer and inner tubes. During continued insertion the inner tube will then glide against the pad and further lubricant will be distributed in the space between outer and inner tubes.

In a simplified not shown embodiment of the invention, the film stocking is single and the lubricant is applied along a part thereof between two half portions, facing towards each other, of the inner surface of the stocking. For use, the stocking is fed into the hole in the lead-through so that the part of it along which the lubricant has been applied, and the length of which corresponds to that of the hole, is in the hole. The sleeve is then inserted into the stocking, which must be kept in place, so that when the sleeve is pressed through the lead-through the portion of the hose covered with lubricant covers the hole wall, thereby facilitating the insertion of the sleeve. In this simplified embodi¬ ment, the thrusting force required is reduced to the same degree as with the previously described embodiment, while the porous material in the lead-through is protected against being penetrated by the lubricant. A certain amount of extra trouble in handling cannot be avoided however, since lubricant will be transferred to the sleeve and to a certain extent also on to the cable pulled through the sleeve.

OMPI

. - V?:PO

Claims

C L A I M S :

1 A lubricant unit intended for application between the contact surfaces of two bodies for reducing friction between them during displacement of the bodies relative each other especially in the case where one or both of the bodies comprises a porous material, characterized in that said lubricant unit in its unapplied condition comprises at least one film (1, 2) arranged with mutually opposing film surfaces, with a lubricant (3) deposited between these surfaces, and in that after placing said unit between the bodies (4, 6) in question, the contact of at least one body is covered by film, whereby the necessary force for surmounting friction between the bodies will depend solely on the friction between a film surface coated with lubricant and a contact surface, or on the friction between two lubricant-coated film surfaces.

2 Lubricant unit as claimed in claim 1, characterized in that the lubricant is absorbed by a layer (10) of an absorbing material placed between the film surfaces facing towards each other, said layer giving up lubricant to the film surfaces when it is subjected to pressure.

Otø-PI