FR3012440A1 - LINEAR WINCH COMPRISING TWO DISSOCATED SELF-CLEANING JAWS ALTERNATIVELY PROVIDING THE TIGHTENING OF A CABLE - Google Patents

Abstract

The present invention relates to a linear winch (10) comprising two self-tightening jaws (17, 18) able to lock in turn a cable (11) at one end of which is fixed a load, the first jaw (17) being connected to a first frame (20) by means of two double-acting cylinders (23, 24) adapted to drive said first jaw (17) in translation along a first portion of said cable (11), and the second jaw (18) being able to be integrally connected to a second frame (21) or by means of two double-acting cylinders adapted to drive said second jaw (18) in translation along a second portion of said cable (11); ), said frames (20, 21) being spaced apart from each other.

Description

FIELD OF THE INVENTION The present invention relates to a linear winch comprising two disengaged self-tightening jaws alternatively ensuring the tightening of a cable. The invention relates to the field of linear winches for which the traction force is performed in a straight force as opposed to drum winches for which the pulling force is performed in a circular force. The invention finds a particularly advantageous application for winches of tensioning cables anchor lines of oil platforms, for winches for laying pipelines, or for winches for setting up risers fuel (or " riser pulling system "in the Anglo-Saxon literature). STATE OF THE ART There are two embodiments of linear winches. French Patent No. FR 1 394 309 describes a linear winch according to a first embodiment. The linear winch comprises a frame on which are fixed symmetrically two double-acting cylinders, flanking a pair of self-tightening jaws able to lock in turn an axial cable at the end of which is fixed a load. These two self-clamping jaws are aligned along an axis of symmetry of the winch, a fixed jaw being integral in translation, along said axis of symmetry of the winch, the cylinders of said double-acting cylinders, and a movable jaw being integral with their pistons. . The operation of lowering said cable by a linear winch according to the first embodiment may, for example, be carried out as follows. In a first step, the fixed jaw is in the closed position and the movable jaw is in the open position, the two jaws being in a first position for which the two jaws are close. The double-acting cylinders are then actuated to move the movable jaw in a second position for which the two jaws are moved apart in a second step. In a third step, the movable jaw is closed and the fixed jaw is opened in a fourth step. The fifth step corresponds to a displacement of the double-acting cylinders between the second position and the first position causing a displacement of said cable. The final steps are to close the fixed jaw and open the movable jaw to return to the first step. This embodiment thus makes it possible to pull the cable intermittently.

The second embodiment comprises two movable jaws. The linear winch comprises a frame on which are fixed symmetrically two pairs of double-acting cylinders, each framing a self-clamping jaw secured to the pistons of a cylinder torque. In this embodiment, the actuation of the jaws is similar to the first embodiment but when a jaw is open, it is moved in translation by the corresponding pair of jacks. This embodiment thus makes it possible to pull the cable continuously. These two embodiments generate an essentially axial space along the axis of the cable. However, this axial size limits the possibilities of implantation of linear winches, especially on mobile circular platforms. DISCLOSURE OF THE INVENTION The present invention intends to overcome the disadvantages of implantation of the two embodiments of linear winches. For this purpose, the invention relates to a linear winch comprising two self-tightening jaws able to lock in turn a cable at one end of which is fixed a load, the first jaw being connected to a first frame via two double-acting cylinders adapted to drive said first jaw in translation along a first portion of said cable, and the second jaw being able to be integrally connected to a second frame or by means of two double-acting cylinders capable of driving said second jaw in translation along a second portion of said cable, said frames being distant from one another. The invention thus facilitates the implantation of a linear winch in a structure by dissociating the position and if this is advantageous, the orientation of the two jaws. According to one embodiment, at least one frame comprises means for guiding the movements of said corresponding jaw. This embodiment makes it possible to support the weight of said jaw.

According to one embodiment, said first portion of said cable is connected to said second portion of said cable via at least one connecting pulley. This embodiment makes it easier to install a linear winch in a structure by dissociating the axial position of the two jaws. According to one embodiment, at least one double-acting cylinder is hydraulic. This embodiment makes it possible to produce very large traction forces. According to one embodiment, at least one double-acting jack is electric. This embodiment makes it possible to limit the bulk of the control and control members of said electric jack.

According to one embodiment, an end of said cable, opposite the end of said cable attached to a load, is connected to a winder. This embodiment makes it possible to store a portion of said cable when it is not fully used. According to one embodiment, the linear winch comprises at least one winding pulley placed between said first portion of said cable and said winder, said winding pulley being able to drive said cable from said first jaw to said winder. This embodiment makes it easier to install a linear winch in a structure by dissociating the axial position of said first jaw and said winder.

According to one embodiment, said frames are integral with each other, said frames being mounted free in translation on a first support plate, the translational movements of said frames being guided by a double-acting cylinder. This embodiment makes it possible to use the linear winch for several predefined use positions. According to one embodiment, said winder is fixed on a second support plate mounted free to rotate relative to said first support plate, the rotation between the two support plates being feasible along an axis of rotation coincides with an axis of rotation of said winding pulley. This embodiment facilitates the implantation of a linear winch into a structure by dissociating the axial position of said jaws and said winder. According to one embodiment, said support plates are rotatable on a circular platform according to at least one rail formed on said circular platform. This embodiment makes it possible to use the linear winch for several predefined use positions. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood from the following description, given purely for explanatory purposes, of the embodiments of the invention, with reference to the figures in which: FIG. comprising two linear winches according to one embodiment of the invention in a perspective view of 3/4 face; - Figure 2 illustrates a linear winch of Figure 1 in a view from above; FIG. 3 illustrates the linear winch of FIG. 2 in a 3/4 face view in perspective and in a first position; - Figure 4 illustrates the linear winch of Figure 2 in a 3/1 face view in perspective and in a second position; and - Figure 5 illustrates the linear winch of Figure 2 in a 3/4 back view in perspective and in the first position. DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION FIGS. 1 to 5 illustrate a linear winch 10 according to one embodiment of the invention for which the linear winch 10 comprises a movable jaw 17 and a fixed jaw 18. The invention also relates to linear winches having two movable jaws.

The linear winch 10 makes it possible to maneuver a cable 11 comprising two ends 14, 15. A load is fixed on the first end 14 while the second end 15 is connected to a reel 29 to store the portion of the cable 11 not used. Alternatively the cable can be stored by any other means.

In addition, contrary to drum winches, the winder 29 of the invention does not participate in pulling said cable 11. The traction is performed by two self-clamping jaws 17, 18. The first jaw 17 is movable, c ' that is to say that it is connected to a first frame 20 by means of two double-acting cylinders 23, 24 disposed on either side of the first jaw 17. The two double-acting cylinders 23, 24 are capable of driving the first jaw 17 in translation along the cable 11. The frame 20 of the first jaw 17 corresponds to the point of attachment of the two double-acting cylinders 23, 24. The frame 20 also comprises a guide means 26 for displacements of the jaw 17 made by two parallel rails.

The second jaw 18 is fixed, that is to say that it is fixed directly on a second frame 21. The two frames 20, 21 are distant from each other, preferably from a distance greater than 50 cm. Alternatively, the second jaw 18 could be movable and actuated by two double-acting cylinders attached to the second frame 21. This embodiment allows for continuous traction.

The two jaws 17, 18 are oriented along two perpendicular axes. A connecting pulley 28, partially shown, makes it possible to direct the cable 11 between the two jaws 17, 18. In a variant, the two jaws can be oriented together in any possible way.

One or more means are then implanted to direct the cable 11 between the two jaws 17, 18. The descent of the cable 11 by the linear winch 10 is performed as follows. In a first step, the second jaw 18 is in the closed position and the first jaw 17 is in the open position, the first jaw 17 being in a first position for which pistons are contained in cylinders of the double-acting cylinders 23, 24. The double-acting cylinders 23, 24 are then actuated to move the first jaw 17 in a second position for which the pistons are out of the cylinders of the double-acting cylinders 23, 24 during a second step. In a third step, the first jaw 17 is closed and the second jaw 18 is opened in a fourth step. The fifth step corresponds to a displacement of the pistons of the double-acting cylinders 23, 24 between the second position and the first position causing a displacement of the cable 11. The final steps consist of closing the second jaw 18 and opening the first jaw 17 to go back to the first step. This embodiment thus makes it possible to pull the cable intermittently. In this embodiment, the double-acting cylinders 23, 24 are actuated by hydraulic energy, they are therefore connected to a hydraulic control and control unit 44. In a variant, the double-acting cylinders 23, 24 may be electrical . During the movements of the cable 11, the portion of the cable 11 which is not stressed is stored in the reel 29. To do this, the cable 11 of the first jaw 17 is connected to the reel 29 by a pulley. winding 30 and a guide pulley 31. The guide pulley 31 can effectively guide the cable 11 in the winder 29 to limit the problems related to a bad winding or unwinding of the cable 11.

Figure 1 also reveals that two linear winches 10 are arranged on a circular platform 37, for example an oil platform. The circular platform 37 has several holes 39 through which cables are hoisted as needed. In order to be able to move the linear winch 10 on the circular platform 37, the two jaws 17, 18 are mounted on a first support plate 35 and the winder 29 is mounted on a second support plate 36. The two support plates 35 , 36 are mounted free to rotate relative to each other, the rotation between the two support plates 35, 36 being feasible along an axis of rotation coincides with an axis of rotation of the winding pulley 30. two plates 35, 36 are also provided with wheels guided in circular rails 38 of the platform 37. The linear winch 10 can thus rotate around the circular platform 37 and cooperate with holes 39 spaced angularly on the platform 37. The cutting two support plates 35, 36 makes it possible to improve the turning radius of the linear winch 11 and therefore to limit the diameter of the platform 37. The first support plate 35 supporting the two jaws 17, 18 also comprises a double-acting cylinder 40 able to move the two jaws 17, 18 to allow the linear winch 10 to cooperate with radially spaced holes 39. In the example of Figure 3, the double-acting cylinder is deployed to allow the linear winch 10 to cooperate with a hole 39 of the outer periphery of the platform 37 while in the example of Figure 4, the cylinder to double effect is folded to allow the linear winch 10 to cooperate with a hole 39 of the inner periphery of the platform 37.

The linear winch 10 of the invention thus makes it possible to achieve a tensile force on a cable 11 by improving the implantation possibilities of the two jaws 17, 18.

Claims (7)

REVENDICATIONS1. Linear winch (10) comprising two self-clamping jaws (17, 18) adapted to lock in turn a cable (11) at one end (14) of which is fixed a load, characterized in that: the first jaw (17) ) is connected to a first frame (20) by means of two double-acting cylinders (23, 24) adapted to drive said first jaw (17) in translation along a first portion of said cable (11), and the second jaw (18) is capable of being integrally connected to a second frame (21) or by means of two double-acting cylinders able to drive said second jaw (18) in translation along a second portion of said cable ( 11), said frames (20, 21) being spaced from each other. 2. Linear winch according to claim 1, characterized in that the at least one frame (20, 21) comprises means (26) for guiding the movements of said corresponding jaw (17, 18). 3. Linear winch according to claim 1 or 2, characterized in that said first portion of said cable (11) is connected to said second portion of said cable (11) via at least one connecting pulley (28). 4. Linear winch according to one of claims 1 to 3, characterized in that at least one double-acting cylinder (23, 24) is hydraulic. 5. Linear winch according to one of claims 1 to 4, characterized in that at least one double-acting cylinder (23, 24) is electric. 6. Linear winch according to one of claims 1 to 5, characterized in that one end (15) of said cable (11), opposite the end (14) of said cable (11) attached to said load, is connected to a retractor (29). 7. Linear winch according to claim 6, characterized in that it comprises at least one winding pulley (30) placed between said first portion of said cable (11) and said winder (29), said winding pulley (30). ) being able to drive said cable (11) from said first jaw (17) to said winder (29).