WO2007063197A1

WO2007063197A1 - Cutting tool and apparatus for cutting lengthwise a protective sheath surrounding at least two cables

Info

Publication number: WO2007063197A1
Application number: PCT/FR2006/002492
Authority: WO
Inventors: Didier Roux
Original assignee: Alroc
Priority date: 2005-11-29
Filing date: 2006-11-08
Publication date: 2007-06-07
Also published as: FR2894084A1; FR2894084B1

Abstract

The invention relates to a cutting tool (1) for cutting lengthways a protective sheath surrounding at least two cables, for the at least partial removal of said sheath, this cutting tool (1) comprising at least one guide shoe (2) capable of being inserted into an unoccupied space between the sheath and the cables, the shoe (2) being surmounted by a plough (7) whose forward or leading edge (8) is sharpened to split the sheath as the tool (1) advances. This cutting tool (1) is characterized in that the shoe (2) has a flat or convex upper surface (5) for bearing on the inside of the sheath and, on the opposite side from the upper surface (5), a sole (6) of convex longitudinal profile between a front end termed the upstream leading edge (3) and a rear end termed the downstream trailing edge (4), so as to reduce the area of contact between the shoe (2) and the cable or cables without risking damaging the sheathed cables.

Description

Cutting tool and apparatus for longitudinal trenching of a protective sheath surrounding at least two cables

The present invention relates to a tool and a cutting apparatus for the longitudinal slicing of a protective sheath surrounding at least two cables, generally in parallel or twisted arrangement, in particular for the at least partial removal of said sheath.

The stripping of cables by at least partial removal of a sheath surrounding said cables is a common practice today to allow in particular the subsequent connection of the cables together. However, cables have more and more complex designs. They can today consist of a plurality of cables surrounded by a sheath, a space being left free between cable and sheath. Inside the sheath, these cables can be in parallel or twisted arrangement. In this second case, the space left free between cable and sheath delimits a helical path. The difficulty lies in the stripping of such cables without damaging them. In such cases, the design cutting tools of the type of that described in DE-2.306.031 or DBP-1.118.293 are unsatisfactory.

Such cutting tools are all based on the same principle. These tools, driven along the sheath, generally manually, using a tool holder or a simple handle have a radial blade edge to the core of the body sheathed in the cutting position of the tool, this cutting edge surmounting a plate of circular shape (DBP1.118.293), or rectangular (DE-2.306.031) intended to be inserted under the sheath and to be supported by its face from above against the inner surface of the sheath. This sole, which participates in guiding the tool, is on the one hand a support against the tool holder when present, on the other hand a member for limiting the depth of cut. This design of a plate provided with acute angles can give satisfaction in the case of a sheath surrounding a solid core but necessarily causes damage to the cables, especially when the path delimited by the cables, inside of the sheath, is a helical path.

An object of the present invention is therefore to provide a tool and a cutting apparatus for the longitudinal slicing of a protective sheath whose design reduces the coefficient of friction between sheath and cables in order to increase the cutting speed. of the tool without increasing the risk of cable damage.

For this purpose, the subject of the invention is a cutting tool for the longitudinal slicing of a protective sheath surrounding at least two cables, generally in parallel or twisted arrangement, in particular in view of the at least partial elimination of said sheath. , this cutting tool comprising at least one guide shoe adapted to fit into a free space between sheath and cables, this pad being surmounted by a fin whose front edge, taken in the direction of travel of the shoe, is cutting edge for splitting the sheath as the tool advances, this advancement being generally obtained by coupling the tool to a tool holder, characterized in that the pad has an upper surface, generally flat or convex, bearing on the inner face of the sheath to slice and, opposite the upper surface, a sole convex longitudinal profile between a front end, said leading edge, and a rear end, said bor d downstream leakage, so as to reduce the contact surface of the pad with the cable or cables and increase the cutting speed by reducing the efforts to the advancement of the tool without risk of damage to sheathed cables.

The convex shape imparted to the sole of the pad reduces the coefficient of friction between pad and cables while limiting the risk of damage to the cables.

The invention also relates to a cutting apparatus for longitudinal cutting of a sheath surrounding at least two cables in rectilinear or twisted disposition, in particular for the elimination of said sheath, this apparatus comprising a cutting tool holder body. , positionable in support on said sheath, and moving along said sheath by appropriate drive means, so as to allow, parallel to the progression of the tool holder body along the sheath, the cutting of the sheath by the cutting tool associated with the tool holder, characterized in that the cutting tool, which comprises a guide pad in the form of an elongate body adapted to be inserted under the sheath in the free space between sheath and cables, this skate being surmounted by a fin whose front edge constitutes a blade cutting edge slitting the sheath, is of the aforementioned type.

The invention will be better understood on reading the following description of exemplary embodiments, with reference to the appended drawings in which:

Figure 1 shows a perspective view of a cutting apparatus according to the invention, the actuating lever of the moving means for moving said apparatus has not been shown;

Figure 2 shows a perspective view of the cutting tool alone;

Figure 3 shows a side view of the cutting tool of Figure 2;

FIG. 4 represents a partially perspective view from below of a cutting tool according to the invention and

Figure 5 shows a perspective view of the cutting apparatus in the state installed on a sheath to be cut.

As mentioned above, the apparatus and the cutting tool 1, object of the invention, are more particularly intended to allow the longitudinal slicing of a protective sheath 14 surrounding at least two cables 15. These cables 15 can be in parallel arrangement or twisted inside the sheath 14. In the example shown, the sheath 14 surrounds three cables 15 and has a triangular profile in cross section. A space 16 is formed between sheath and cable due to the plurality of cables 15 enclosed within said sheath. The cutting apparatus and the associated cutting tool are intended to split the sheath 14, the slot being shown at 17 in FIG. 5, to allow at least partial elimination of this sheath 14. The apparatus and the cutting tool allows to proceed to a longitudinal slicing of the sheath 14, a circumferential slicing being generally performed by an additional cutting tool.

The cutting tool, which is the subject of the invention and represented in FIGS. 2 to 4, comprises, in known manner, at least one guiding pad 2 capable of being inserted into a free space 16 between sheath 14 and cables 15 and a fin 7 positioned above the pad 2. The front edge 8 of the fin 7, taken in the direction of travel of the pad 2, is in the form of a cutting edge to split the sheath 14 as and when measuring the advancement of the tool 1 along the sheath. The fin 7 thus originates on the upper face of the pad and extends in a substantially orthogonal or radial plane to said upper surface. In the examples shown, this fin 7 is extended by a section 9 for fixing the cutting tool to a tool holder 10. The fin 7 is thus surmounted by a securing section 9 and is thus interposed between pad 2 and section 9 for fastening the cutting tool 1 to a tool holder 10. This fixing section 9 is provided with holes or tappings for fixing the cutting tool 1 to a tool holder 10 by the intermediate screwing members or pins. Generally, this attachment can operate in an adjustable manner to take into account the thickness of the sheath.

Due to the relative positioning of the fin 7 with respect to the shoe 2, the cutting edge constituted by the front edge 8 of the fin 7 extends in a substantially radial plane to the body to be stripped in the inserted state of the shoe in a free space 16 between sheath 14 and cable 15. The pad 2 is, in turn, in the form of an elongated body which has an upper surface 5, generally flat or convex, bearing on the inner face of the sheath 14 to slice. In the examples shown, this upper surface has been made flat. In general, this upper surface can be made in the form of complementary to the internal profile of the sheath. It can therefore be made in convex form, that is to say of convex shape taken in the transverse direction of said surface to fit the generally concave interior profile of said sheath. This upper surface of the pad 2, movable sliding contact against the inner face of the sheath, ensures guiding of the pad 2 as the advance of the cutting tool 1 along said sheath . Opposite the upper surface of the pad 2, the pad 2 comprises a sole 6 with a convex longitudinal profile between a front end, said upstream edge 3 of attack and a rear end, said downstream edge 4 of said skid . This convex profile, as shown in FIG. 3, makes it possible to reduce the contact surface of the shoe 2 with the cable or cables 15. Furthermore, this rounded profile makes it possible to limit the risk of damaging the sheathed cables. The convex profile of the sole develops here over the entire length of said sole 6 of the shoe 2. In addition, this sole 6 of the shoe 2 has, throughout its length, a convex transverse profile to easily follow a cutting path with a reduced coefficient of friction without risk of damaging the sheathed cables to be stripped. The fact for said sole 6 to have both a longitudinal profile and a convex transverse profile provides the said sole a rounded profile preventing damage to sheathed cables to denude. To complete this rounding of shapes, the leading edge 3 of the pad 2 has softened frontal shapes. These different profiles given to the sole allow to give it, at the level of the tapered front end, a general conical shape seen from below. The connection between the sole and the upper face of the pad is effected by means of side walls of the pad. These side walls are, because of the forms imparted to the sole, connected to said sole by curved lines thus allowing the sole to pivot about a longitudinal axis of the shoe. This facilitates the movement of the pad within a helical guideway. The tapered shape that is imparted to the front end of the pad further facilitates the penetration and advancement of said pad.

As said shoe progresses, the cutting edge of the fin 7, which is disposed in the plane, perpendicular or radial to the upper surface of the skid, passing through the median longitudinal axis of the pad 2, with reference to the pad is inclined from a low point forward to a rear high point. The fact of having an oblique cutting edge upward from the leading edge towards the trailing edge of the pad, facilitates the slicing of the sheath because the slicing is a gradual slicing of the thickness of the sheath. Again, this provision contributes to the reduction of efforts to the advancement of the tool.

To allow relative movement between tool and sheath, different possibilities can be envisaged. The preferred solution is a movement of the tool along the sheath. However, a solution in which the sheath would be moved along the tool should be considered as an equivalent solution. In the preferred solution, the advancement of the tool along the sheath can be obtained manually or automatically. In the examples shown, this advance is obtained by coupling the tool 1 to a tool holder 10. This tool holder 10 is in the form of a cutting apparatus comprising a support body 10 which can be positioned in abutting position. on said sheath 14 and moving along the sheath 14 by appropriate drive means. Thus, parallel to the progression of the tool holder body along the sheath 14, there is a cutting of the sheath 14 by the cutting tool 1 associated with the tool holder 10.

In the example shown, this tool holder 10 is equipped with a toothed wheel 11, adapted to come into bearing contact on the outer face of the sheath 14 in the inserted state of the shoe 2 in the sheath 14, in particularly in a free space 16 between sheath 14 and cable 15. The rotational drive of the toothed wheel 11 by a suitable member, such as a lever 12, in particular a ratchet lever, a crank or the like, makes it possible to ensure the manual movement of the tool holder 10 along the sheath 14.

In this embodiment, in the coupled state of the cutting tool 1 to the tool holder 10, at least a portion of the tool holder 10 extends vertically above the front end of the shoe 2 of the 1 and delimits, with said front portion of the pad 2, a space insertion of the sheath 14 substantially corresponding to the thickness of the sheath 14 to be slit. In the example shown, that portion of the tool holder which extends vertically above the front end of the shoe 2 corresponds to the toothed wheel of said cutting apparatus. The sheath is thus clamped between the toothed wheel and the upper face of the shoe 2 which constitutes a counter-support to the toothed wheel.

The sole 6 of the shoe 2, which abuts on the cables, allows for it to regulate the depth of cut and adjust the latter. The cutting apparatus is further equipped with a handle 13 which allows the operator to hold the cutting apparatus with one hand while his other hand operates the drive lever 12 in motion. the tool cutter along the sheath.

The operation of such a set is as follows. The cutting tool, which is generally mounted interchangeably on the cutting apparatus, is installed on said apparatus and is set in position on said apparatus according to the desired depth of cut. The front end of the shoe 2 of the cutting tool is then inserted into the free space 16 between sheath 14 and cables 15, until the front edge of the fin comes into bearing contact on the sheath. 14 to be sliced. Meanwhile, the toothed wheel is brought into bearing on the outer face of said sheath at the base of the front end of the pad. The sheath is thus clamped between the toothed wheel and the upper face of the pad. The cutting operation can then begin. It is sufficient, for this purpose, to the operator, who holds with one hand the handle 13 of the tool holder and the other hand the lever 12 of the tool holder, to drive in angular displacement this lever. This angular displacement of the lever 12 of the tool carrier causes the rotational movement of the gearwheel and, consequently, the advancement of the toolholder / cutting tool along said sheath. During this advancement, the front edge 8 of the fin 7 splits the sheath making a slot 17 of the type shown in Figure 5. When the path between cable and sheath is a helical path, the cutting device tool holder tends, during its movement to follow a helical path and thus to rotate around said sheath during slicing of the sheath while progressing along the latter. When the sheath has been cut for a sufficient length, the cutting apparatus and its associated cutting tool are removed by reverse displacement before complete elimination of the cut sheath portion using a suitable cutting tool.

Claims

1. Tool (1) for cutting for the longitudinal slicing of a protective sheath (14) surrounding at least two cables (15), generally in parallel or twisted arrangement, in particular to eliminate at least partially said sheath (14), this cutting tool (1) comprising at least one guide shoe (2) adapted to fit into a space (16) free between sheath (14) and cables (15), this shoe (2) being surmounted by a fin (7) whose edge (8) frontal, taken in the direction of advance of the shoe (2), is sharp to split the sheath (14) as the progress of the tool (1), this advancement being obtained generally by coupling the tool (1) to a tool holder (10), characterized in that the shoe (2) has an upper surface (5), generally flat or curved, bearing on the inner face of the sheath (14) to slice and, opposite the upper surface (5), a sole (6) with a convex longitudinal profile between a front end, called edge (3) of upstream attack, and a rear end, said edge (4) downstream leakage, so as to reduce the contact surface of the pad (2) with the cable or cables (15) and increase the cutting speed by reducing the forces to the advancement of the tool (1) without risk of damage to the cables (15) sheathed.

2. Tool (1) for cutting according to claim 1, characterized in that the sole (6) of the shoe (2) has, along its length, a convex transverse profile to easily follow a cutting path with a coefficient of friction reduces without risk of damage to the sheathed cables (15) to be stripped.

3. Tool (1) for cutting according to one of claims 1 and 2, characterized in that the edge (3) of attack of the shoe (2) has softened frontal shapes.

4. Tool (1) for cutting according to one of claims 1 to 3, characterized in that the fin (7) is surmounted by a section (9) for fixing the cutting tool (1) to a tool holder (10).

5. Tool (1) for cutting according to one of claims 1 to 4, characterized in that the cutting edge of the fin (7) is disposed in the plane perpendicular or radial to the upper surface (5) of the pad (2). ) which passes through the median longitudinal axis of the shoe (2), this cutting edge being, with reference to the shoe (2), inclined from a front low point to a rear high point.

6. Cutting apparatus for longitudinal cutting of a sheath (14) surrounding at least two cables (15) in rectilinear or twisted disposition, in particular for the elimination of said sheath (14), this apparatus comprising a body (14) 10) cutting tool holder, positionable abutting on said sheath (14), and moving along said sheath (14) by appropriate drive means, so as to allow, parallel to the progression of the door body tool along the sheath (14), cutting the sheath (14) by the cutting tool (1) associated with the tool holder (10), characterized in that the cutting tool (1), which comprises a guiding pad (2) in the form of an elongated body adapted to be inserted under the sheath (14) into the free space (16) between the sheath (4) and the cables (15), this pad (2) being surmounted by a fin (7) whose front edge (8) constitutes a blade cutting edge slitting the sheath (14), is according to one of claims 1 to 5.

Apparatus according to claim 6, characterized in that in the coupled state of the cutting tool (1) to the tool holder (10), at least a portion of the tool holder (10) extends to the plumb with the front end of the shoe (2) of the tool (1) and defines, with said front portion of the shoe (2), an insertion space of the sheath (14) substantially corresponding to the thickness the sheath (14) to be split.

8. Apparatus according to one of claims 6 and 7, characterized in that the tool holder (10) is equipped with a toothed wheel (11) adapted to come into bearing contact on the outer face of the sheath. (14), in the inserted state of the shoe (2) in the sheath (14), the rotation drive of the toothed wheel (11) by a suitable member, such as a lever (12), a crank or similar, ensuring the manual movement of the tool holder (10) along the sheath (14).