CH716560A2 - Drive device for pushing or pulling a wire without damaging its peripheral surface. - Google Patents

Abstract

A drive device for pushing or pulling a wire without damaging its peripheral surface according to the invention comprises a casing (1) in which is arranged a pulley driven by a motor (2). In the housing is arranged a rotating crown (5) having at its circumference a U-shaped groove with a flat bottom or V-shaped whose opening is directed towards the outside of said crown. This crown is driven in rotation by a flexible flat or toothed belt (3) of width equal to or less than the distance between the two branches of said U, so as to pass between the two branches of said U and to maintain pressure on said wire in the bottom of said groove. Said belt is driven by passing over said pulley. Said casing comprises an inlet tube (10) and an outlet tube (9), these said tubes being provided for introducing said wire into the groove around the crown by forcing it to make at least one turn of the latter and to bring it out of said groove.

Description

Description

The present invention relates to a drive device for pushing or pulling a wire without damaging its peripheral surface, comprising a casing in which is arranged a pulley driven by a motor. This type of device is generally used to introduce wires or optical fibers into pipes.

[0002] The problem of introducing electric cables in particular into conduits or ducts has been known for a long time. Descriptions of this latter problem can be found, for example, in published patent applications WO 2010/111801 and FR 82537795.

Currently this problem has been solved in particular by devices such as those exposed, for example, in the publications US 2556484 (published on 06.12.1951), US 6722603 (published on 04.20.2004) and US 4413808 (published on 08.11. 1983). All these known devices define devices comprising a casing in which is wound a length of wire intended to be introduced into and emerges from a tube. Thus, they can be used in installations which have tubes which have a length which must be less than the length of the wire contained in the devices. To use these devices in installations which have longer tube lengths it will be necessary to change the reserve of wire in the said devices, which will bring about technical complications. In addition, these devices are complicated and relatively expensive.

[0004] Devices are also known which do not have the defects of the devices described above, for example in patent FR 1,586,534 (published on 02.20.1970), a device is described which is in the form of a a gun and can push or pull a steel wire through a tube. The steel wire is pushed or pulled by being clamped elastically between two pairs of discs. This device can only be used with a steel wire, because it requires strong pressure to move it. This device cannot be used with synthetic material threads, even less with optical fibres.

Another device is described in patent ES 2561703 (published on 04.02.2016). This last device works in the same way as that described in the French patent, so it will be unusable with synthetic threads or optical fibers.

[0006] The aim of the invention is to provide a drive device for pushing or pulling a wire without damaging its surface, which does not have the defects of known devices, that is to say which does not comprise yarn reserve and which can be used with synthetic yarns or optical fibres, and moreover which is light, comprising few parts, therefore easy to manufacture, therefore inexpensive.

[0007] These objects are achieved with the drive device for pushing or pulling a wire without damaging its peripheral surface according to the invention defined in claim 1.

The invention will be better understood and its advantages will appear more clearly on reading the description of embodiments, given solely by way of example, with reference to the drawings in which:

Figure 1 shows a schematic perspective view of a device according to the invention showing only the bottom of the casing under its front face.

FIG. 2 represents a schematic perspective view of the device represented in FIG. 1 showing only the bottom of the case under its rear face.

Figure 3 shows the same device as that of Figure 1 with more details.

Figure 4 shows a schematic plan view of the device shown in Figure 1.

Figure 5 represents a schematic view of section A-A of Figure 4.

Figure 6 represents a schematic perspective view of section A-A of Figure 4.

Figure 6B schematically represents a detail of Figure 6.

Figure 7 shows a schematic perspective view of another form of execution.

Figure 8 shows a section through wedge 8 of Figure 7.

Figure 9 shows a schematic plan view of another embodiment of the device than that shown in Figure 1.

Figure 10, 11 and 12 each represent a detail of several variants of the embodiment shown in Figure 9.

In order to facilitate understanding of the figures, all the characteristics of the invention have the same reference signs in all the figures.

Claims (8)

[0010] The device shown in FIG. 1 represents an embodiment of the device claimed in claim 1. This device comprises a casing of which it has been shown that the bottom 1 comprising an opening 29. On this bottom 1 are arranged on the front side , which represents the part arranged inside said case, a crown 5 having on its circumference a groove 18, see FIG. 6B, in the shape of a U with a flat bottom, the opening of which is directed towards the outside of said crown in place by guide blocks 7a and 7b, and a pulley 4 rotating around shaft 13, and tubes 9 and 10. Pulley 4 is kept in rotation by motor 2 by means of a reduction unit 12 placed on the posterior side opposite the anterior side. Reduction unit 12 drives shaft 13 which is fixed to pulley 4. The pulley 4 can have a smooth or knurled surface, but it can also have a groove into which the belt 3 is inserted. The belt 3 is inserted into the groove 18 of the crown 5, see FIG. 6B. The belt 3 driven by the pulley 4 rotates the crown 5. In addition the belt 3 covers the turns of wire 11 (fig 6B) arranged in the groove 18 by compressing them on the bottom of said groove. For the belt 3 to ensure proper rotation of the crown 5, means for tensioning said belt are provided, these tensioning means are for example constituted by a roller 6 arranged freely in rotation on the axis 14 and resting by its surface peripheral on the inner surface of crown 5. Roller 6 can move substantially radially relative to crown 5. Indeed, see FIG. 2, roller 6 is mounted on a shaft 14 fixed on a lever 19, this lever has articulated on an axis 15. The lever 19 is pulled by a spring 20 by means of tax 22 and said spring is fixed on the rear side of the bottom 1 by means of an axis 21. The spring 20 can comprise adjustment means of its voltage, these means are not represented because they are within the reach of a person skilled in the art. In addition, the belt 3 could be tensioned by a device comprising a lever held by a spring, these tensioning means are not shown because they are within the reach of a skilled person. [0012] In FIG. 3, the device represented in FIG. 1 is loaded with a wire 11, comprising at its end a probe 23, ready to be introduced into a tube 25 placed in a box 24 placed in a wall. To load a thread into the device, it is necessary to introduce the thread 11 into the tube 10 fixed on the bottom 1 by the wedge 16 and push it inside so that it passes between the guide wedge 8 and the crown 5 in the groove 18 (see Figure 6B). The wire 11 will continue its way in the groove 18 held at the bottom of the latter by the belt 3. Then the wire 11 will go around the crown 5 in the groove 18 and will pass under the guide wedge 8. The wedge 8 has a width slightly inside the distance separating the two uprights of said U so that it can be held between them by holding the wire 11 against the crown 5 increasing its friction on the latter. Depending on the diameter of the wire 11 and the width of the groove 18, the wire 11 will make more than one turn on the crown 5, then it will come out through the tube 9 fixed on the bottom 1 by the wedge 7 and will be introduced into the tube 25 by probe 23. In another form of execution (see Figure 7). It is planned to remove the roller 6, the tension of the belt 3 being carried out by the guide wedge 8 mounted on elastic means and able to move against the crown 5. The elastic means ensuring the displacement of the wedge 8 are similar to those described for the roller 6 in FIG. 2. The wedge 8 has a width slightly inside the distance separating the two uprights of said U so that it can be held between the latter by holding the wire 11 against the crown 5 increasing its friction on the latter. Wedge 8 has rollers 28 bearing against wire 11 to facilitate movement of wire 11. Rollers 28 are mounted on pins 26 in wedge 8 (see Figures 7 and 8) and this wedge is fixed to rod 27 , which is attached to a lever identical to lever 19, not shown. Thus wedge 8 will push crown 5 away from pulley 4 and tension belt 3. In a third embodiment shown in Figure 9, with a detail shown in Figure 12. The embodiment is close to that shown in Figure 7, the main difference being that the crown drive 5 is ensured by a chain 29. As can be seen in FIG. 12, it is the chain 29 which ensures that the wire 11 is held under pressure in the V-groove 31 provided in the bottom 18. In a variant of the embodiment shown in Figure 9, with a detail shown in Figure 10, the chain is replaced by a toothed belt 3 as in the embodiment shown in Figure 1. As as can be seen in figure 10, it is the belt 3 which maintains the wire 11 under pressure in the groove 31 provided in the bottom 18. In a final variant of the embodiment shown in Figure 9, with a detail shown in Figure 11, the chain is replaced by a belt of circular section 30 is the bottom of the U is no longer flat but in the shape of a V. As can be seen in FIG. 10, it is the belt 30 which ensures the maintenance under pressure of the wire 11 in the bottom of the V. [0017] The invention makes it possible to obtain a drive device for pushing or pulling a wire without damaging its peripheral surface, having a great pushing or pulling force, because the friction force on the crown is ensured by the pressure of the belt on wire 11. Claims 1. Drive device for pushing or pulling a wire without damaging its peripheral surface, comprising a housing (1) in which is arranged a pulley (4) driven by a motor (2), characterized in that in the housing is also arranged a rotating crown (5) having at its circumference a U-shaped groove (18, see FIGS. 6B, 10, 11, 12), comprising a flat or V-shaped bottom, the opening of which is directed towards the exterior of said crown, driven in rotation by means (3, 30, 29), passing between the two branches of said U, and maintaining pressure on said wire in said groove (18), said means being driven by passing over said pulley (4), and in that said box comprises an inlet tube (10) and an outlet tube (9), these said tubes being provided for introducing the said wire into the said groove (18) around the crown, forcing it to make at least one turn of this last and to bring it out of said groove (18). 2. Device according to claim 1, characterized in that the means are a flexible flat or cogged belt (3) of width equal to or less than the distance between the branches of said U and maintaining pressure on said wire against the flat bottom of the groove (fig 6B). 3. Device according to claim 1, characterized in that the means are a flexible flat or cogged belt (3) of width equal to or less than the distance between the branches of said U and in that the bottom of said U is flat presenting in its middle a V-shaped groove in which is the thread held in pressure by the belt. 4. Device according to claim 1, characterized in that the means are a belt of circular section (30, fig 10) of diameter less than the distance between the branches of said U and in that the bottom of said U is V-shaped in which the wire is kept under pressure by the belt of circular section. 5. Device according to claim 1, characterized in that the means are a chain (29, fig 12) and in that the bottom of said U is flat and has in its middle a V-shaped groove in which the wire is held under pressure by the chain. 6. Device according to one of claims 2 to 5, characterized in that in the case there are provided means for tensioning (6, 19, 20, 8) the belt or the chain and means (7a and 7b) for positioning the crown. 7. Device according to claim 6, characterized in that the means for tensioning said belt or chain are constituted by a roller (6) resting by its peripheral surface on the lower surface of the crown (5), said roller being mounts on elastic means moving it away from the pulley (4) so as to tension the belt. 8. Device according to claim 6, characterized in that the means for tensioning said belt or chain are constituted by a guide wedge (8) mounted on elastic means and this wedge being of width less than the distance separating the two branches of said U so that it can be maintained between them by maintaining the wire against the crown (5).