FR2624773A1 - Abrasive thread and method for manufacturing such a thread - Google Patents

Abstract

According to the invention, the thread includes a core consisting of longitudinal textile fibres 3, a first layer of abrasive 1a, at least one braid 2 and an outer abrasive layer 1. Applications: thread intended to be mounted on a rotating machine.

Description

ABRASIVE THREAD AND PROCESS FOR PRODUCING SUCH A THREAD
The present invention relates to an abrasive wire intended in particular, but not exclusively, for cutting and / or machining of different materials such as wood, plastics, metals, stone, cement, etc. .

It aims to allow the production of a cutting wire flexible enough to be used on rotating machines of the band saw type, or on machines with reciprocating motion.

It is already known to cut materials using wire. In particular, in brushcutters, the cutting member being constituted by a nylon thread driven at high speed.

However, the materials which can be cut by a wire are currently only soft materials.

There are also known cutting tools and, for example diamond discs, constituted by a substrate carrying a resin inside which are included abrasive particles and for example industrial diamond dust. These tools cannot be mounted on machines such as those mentioned above.

The object of the present invention is to overcome the drawbacks mentioned above, by proposing an abrasive wire which can be mounted on a rotary machine, and its continuous manufacturing process.

According to the present invention, the abrasive wire to be cut or machined is characterized in that it comprises a central core constituted by parallel wires impregnated with a thermosetting resin loaded with abrasive grains, all being regularized and held tight by one or more braids , also covered with a substantially uniform layer of abrasive grains.

The present invention also relates to a process for the continuous production of a wire as above.

Other characteristics and advantages of the present invention will become apparent during the following description of a particular embodiment, given solely by way of nonlimiting example, with reference to the drawings which represent - the figure.l, a partial section view of an abrasive wire
according to the invention - Figure 2, a view of a device for implementing the
process.

In FIG. 1, it can be seen that the external part of the wire is entirely composed of abrasive grains 1. These grains can be chosen from the whole range of existing abrasives with a particle size appropriate to the quality of the cut that it is desired to obtain. The central part of the wire is made up of parallel fibers chosen according to their mechanical strength and their elongation module. They can be constituted for example by Kevlar. All of the fibers of the core and of the first layer of abrasive la, are held tight by a braid 2. This braid is composed of fine wire, the purpose of which is to obtain, during manufacture, a wire having a suitable circular section. . All of the components of the wire are amalgamated by a binder 4 which is advantageously a thermosetting resin such as an epoxy resin or a polyester resin. Thus, the product while remaining flexible can withstand the heating generated by the contact of the wire on the material to be cut. It is of course possible to use one or more braids depending on the characteristics sought.

Such a wire can be manufactured continuously, which makes it possible to lower its cost price.

In FIG. 2, it can be seen that the fibers intended to constitute the central core, are delivered to the manufacturing machine proper, by an unwinder it or by a creel 12. The number of fibers and the titration of these is calculated according to the mechanical characteristics desired for the finished product. All of these fibers pass through an impregnation tank 13 filled with a thermosetting resin, polyester or epoxy for example. At the outlet of the impregnation tank 13, the wire rises vertically and passes through an abrasive resin 14, the resin being in the liquid and sticky state, the abrasive grains accumulate outside the core . The assembly then enters from below into a braiding loom 15 which deposits a sheath 2 on the outside of the wire. This braiding makes it possible to mechanically fix the ~ abrasive grains, to perfectly round the wire and to cause a rise resin on the surface improving the fixation of the grains. At the end of the braiding machine, there is a second reserve of abrasive 16 which increases the quantity of abrasive deposited. This abrasive naturally sticks to the excess resin that appears on the surface after the braiding operation. The wire 5 then passes through an oven 16 which allows total polymerization of the resin. Outside the oven 16 there is a pulley 17 for returning downwards, the wire being driven at constant speed by a capstan 18, then finally wound on a storage reel 19.

EXAMPLE: An abrasive wire according to the invention was produced with
the following components - Parallel core: 2 roving 4800 Tex glass E wires - Braid: 16 spindles of polyamide 66 HT 234 dtex
Mesh: 8 meshes / 5 mm - Abrasive: Corundum type, grain size: 100.14 g / m.

It goes without saying that many variants can be introduced in particular by substitution of technically equivalent means without departing from the scope of the invention.

Claims (2)

1. Abrasive wire characterized in that it comprises a core  consisting of longitudinal textile fibers (3), a  first layer of abrasive (la), at least one braid (2), and  an outer abrasive layer (1). 2. Method of manufacturing an abrasive wire according to the  claim 1, characterized in that it consists of  impregnate a set of parallel wires (3) with a  thermosetting resin (4), to pass the assembly  impregnated in a first reserve (14) of abrasive  to deposit outside the assembly obtained a braid (2)  causing the exudation of the resin (4), then to do  pass the compound obtained in a second reserve (16)  abrasive where the wire is completely loaded with grains  polymerizing the resin (4) in an oven (16).