EP0752255A1 - Mobile fall arrest device for flexible safety rope - Google Patents

Abstract

The grip has a vertical channel (9) through which the support cable passes slidably along a vertical axis (YY'). A cam (10) formed by a ramp surface of a pivotable lever (16) selectively engages the cable as it passes through the channel, moving between open and closed positions in response to manual actuation of the lever. The free end of the lever includes a hole (23) through which a carabineer or other clip may be passed and secured. When located in the hole, the projecting ends of the clip engage stop surfaces (20a,b) on the casing of the grip, preventing pivoting movement of the lever from a closed position of the cam to its open position.

Description

The present invention relates to an individual safety device against falls from a height. It relates to a mobile fall arrester for belay support more particularly suitable for vertical belay supports, in particular flexible belts, such as cables or ropes.

The personnel who are called upon to work on high installations and who must climb or descend along pylons or poles for this purpose must be insured so as not to fall unexpectedly. This is, for example, the case for installers or repairers of installations such as, for example, cableway or chairlift installations. It is therefore necessary to insure them so that they can climb or descend in complete freedom, and this, without the risk of falling.

There are already known such devices constituted by a rope or belay cable arranged vertically, also called "lifeline", to which the user connects so as to be able to move up or down. For this purpose, it is equipped with personal protective equipment connecting it to the "lifeline" and comprising a harness fixed to a mobile fall arrester. However, the known devices are not entirely satisfactory in terms of their convenience of use and their reliability.

The present invention provides a new device which is particularly safe, reliable and convenient to use.

Thus, according to the invention, the mobile fall arrester for belay support such as a cable or a rope, is of the type comprising an axis retaining groove, in which said belay support is retained by means of a cam , and is characterized in that the ramp is secured to a pivoting lever between an open position and a closed position, and the free end of which comprises a hole intended to receive a carabiner, while a stop system for the limit carabiner pivoting of the lever in an intermediate position when passing from the closed position to the open position.

According to a preferred arrangement, the retaining groove is produced by the wall of a main flange, while the fall arrester comprises a secondary flange constituted by a wall, the lever being pivotally mounted between the two flanges.

According to an additional characteristic of the invention, there is provided a longitudinal passage parallel to the axis of the groove, said passage being limited laterally by, on the one hand, the first edge of the main flange and, on the other hand, the first border of the second flange.

According to another additional characteristic, the second edges include a clearance allowing the lever to move with its carabiner and delimiting the stops defining the intermediate position of the lever.

In a preferred embodiment, given by way of example, the second lateral border of each of the flanges comprises a succession of two ramps, a lower ramp recessed with respect to an upper ramp to form the clearance. The lower ramp is circular with radius centered on the axis, while the upper ramp is circular with radius centered on the axis, knowing that the radius of said upper ramp is greater than the radius of said lower ramp, the clearance formed by the lower recessed ramp, is limited upwards by the stops arranged radially and substantially in the horizontal plane passing through the pivot axis of the lever.

According to other additional features of the invention, the lever cam is constituted by a locking ramp extended by an unlocking ramp, while the width of the lever is such that it projects beyond the upper ramps when the lever is in the extreme open position.

Other characteristics and advantages of the invention will emerge from the description which follows with reference to the appended drawings which are given only by way of nonlimiting examples

Figure 1 is an overview illustrating how the fall arrest device of the invention is used.

Figure 2 is a side view showing more particularly the fall arrester mounted on the belay cable and its connection to the harness worn by the user.

Figures 3, 4 and 5 are execution views of the fall arrester; Figure 3 is a plan view, Figure 4 is a side view of the lever side, while Figure 5 is a top view.

Figure 6 is a view similar to Figure 3 but illustrating the fall arrester, in its extreme open position showing the various elements constituting the fall arrester.

Figure 7a is an exploded perspective view, while Figure 7b is a perspective showing the mounted fall arrester.

FIGS. 8 to 12 illustrate the different stages of setting up the fall arrester of the invention.

Figure 13 shows how the fall arrester according to the invention is used.

Figure 14 is a view similar to Figure 5 showing an alternative embodiment with a partial section along the pivot axis of the lever.

Figures 15, 16 and 17 illustrate an alternative embodiment, Figures 15 and 16 being views similar to Figures 3 and 6.

The mobile fall arrester (1) is part of personal protective equipment against falls from a height bearing the general reference (2) and comprising, in addition to said fall arrester (1), a harness (3) carrying at least one mooring loop. (4) with a hooking carabiner (5), said fall arrester (2) being intended to be removably connected to a vertical belay support (6) fixed, for example, on an intervention pylon (7).

In its position of use, i.e. connected to the harness (3), the mobile fall arrester (1) can be moved up (HA) or down (BA) at will by normal sliding ( that is to say at the speed of ascent or descent of the user) along the vertical cable (6) constituting the belay support which can, moreover, be constituted by a rope. In the event of a fall, which corresponds to an accelerated descent speed, the mobile fall arrester locks onto the cable. It will be understood that the user (8) can then climb or descend along the pylon (7) while sliding the fall arrester upwards (HA) or downwards (BA) along the safety cable (6), if necessary, while it will be ensured not to fall down by blocking its fall arrester (1) on said cable (6) constituting the belay support.

The fall arrester (1) essentially comprises a straight hollow profile (9) intended to receive the belay cable (6) which is retained there after engagement, thanks to a cam (10) movable in pivoting. Thus, the hollow profile (9) consists of the wall (11a) of a main flange (12a) whose first side edge (13a) is folded parallel to said wall, so as to form a gutter or a semi groove -circular (9), while the second lateral border (14a) is in the plane of the wall and is curved to include a clearance (15a) at its lower part. Note that the groove has a semi-circular profile with a vertical axis (YY ') and has substantially the dimension of the cable intended to be housed there. Furthermore, the locking cam (10) is integral with an operating and latching lever (16) which is pivotally mounted on the fall arrester around a transverse axis (XX ').

Note that the second lateral border (14a) comprises a succession of two ramps, a lower ramp (17a) set back relative to an upper ramp (18a) to form the clearance (15a). The lower ramp is circular with radius (R1) centered on the axis (XX '), while the upper ramp is circular with radius (R2) centered on the axis (XX') knowing that the radius (R2) of said upper ramp is greater than the radius (R1) of said lower ramp. Furthermore, the clearance (15a) whose function will be explained later in the description, formed by the lower recessed ramp, is limited upwards by a stop (20a) arranged radially and substantially in the horizontal plane (H) passing by the pivot axis (XX ') of the lever (16).

The body of the mobile fall arrester comprises, in addition to the main flange (12a) described above and forming the groove (9), a secondary flange (12b). The latter is integral with the main flange to be parallel to it and spaced by a distance (d) to constitute, on the one hand, a space (e) between the two flanges intended for the movement of the lever (16) and, on the other part, a longitudinal passage (40) for the engagement of the cable (40). The secondary flange has a configuration identical to the wall (11a) of the main flange (12a). Thus, it is constituted by a wall (11b) and comprises a first rectilinear lateral border (13b), while the second lateral border (14b) is in the plane of the wall and is curved to include at its lower part a clearance ( 15b). Thus, the second lateral border (14b) comprises a succession of two ramps, a lower ramp (17b) set back relative to an upper ramp (18b) to form the clearance (15b). The lower ramp is circular with radius (R1) centered on the axis (XX '), while the upper ramp is circular with radius (R2) centered on the axis (XX'), knowing that the radius (R2) of said upper ramp is greater than the radius (R1) of said lower ramp. Furthermore, the clearance (15b), the function of which will be explained later in the description, formed by the lower recessed ramp, is limited upwards by a stop (20b) arranged radially and substantially in the horizontal plane (H) passing by the pivot axis (XX ') of the lever (16). Let us add that the passage (40) is laterally limited by the first border (13a) of the main flange (12a) and the first border (13b) of the secondary flange (12b). Of course, the width of the passage is greater than the diameter of the cable (6) intended to be engaged therein, said passage extending parallel to the axis (YY ') of the groove.

The lever (16) previously mentioned is disposed so as to pivot about the axis (XX '). It is arranged to move between the two flanges (12a, 12b), in the space (e) formed between the main flange (12a) and the secondary flange (12b). It is thus mounted in rotation about an axis (21) extending between the two flanges so that its attachment end (22) extends beyond the lower ramps (17a, 17b) of the two flanges (12a , 12b), in the area created by the clearances (15a, 15b). Said free hooking end (22) further comprises a hooking hole (23) intended to receive the hooking carabiner (5) which can be engaged therein thanks to the clearance (15a, 15b) provided on the edges of the flanges (12a, 12b). The hanging hole (23) is cylindrical and its axis (QQ ') is at a distance (L1) from the axis (XX') between the value of the radius (R1) of the lower ramp (17a, 17b) and the value of the radius (R2) of the upper ramp (18a, 18b). In addition, its diameter is such that its peripheral wall (24) is at a distance (L2) from the axis (XX ') greater than the radius (R2).

Furthermore, the lever (16) comprises, on the side opposite to the hanging hole (23), a cam (10) constituted by a locking ramp (25) for blocking the fall arrester (1) on the cable. belay extended by a release ramp (26) of the fall arrest device allowing said fall arrest device to slide on said belay cable (6). The lever (16) being able to assume by rotation about the axis (XX ') two extreme positions, an open position as illustrated in Figures 6 and 8, and a closed position as shown in Figures 3, 10 , 11 and 12.

Note that the lever is constantly biased towards its closed position by a torsion spring (27). The latter is useful, on the one hand, for maintaining the fall arrester (1) on the belay cable (6) at the time of fitting and removing the carabiner (5) and, on the other hand part, to ensure that the fall arrester is blocked in the event of a fall, even before the carabiner (5) has to pivot the lever down by itself. Let us add that the fall arrester comprises two stops (28, 29) to limit the angular displacement of the lever downwards by a lower stopper (28) and upwards by an upper stopper (29). The lower stop (28) is made by a small transverse wall (30) extending between the two flanges (12a, 12b) in the area of the lower ramps (17a, 17b), while the upper stop (29) is made by an upper cylindrical spacer connecting the upper position of the two flanges (12a, 12b).

FIGS. 8 to 12 illustrate the different stages of setting up the fall arrester of the invention. The user by placing the first flange (12a) of the fall arrester (1) in the palm of the right hand rotates with his thumb the lever (16) upwards according to R1 to clear the passage (40) for the cable . He brings the fall arrester (1) on the cable (6) to pass said cable (6) for the passage (40), as illustrated in FIG. 8. Then he engages the cable (6) in the groove ( 9) and releases the lever (16), as illustrated in FIG. 9. The lever (16) biased by the spring (27) pivots downward along (R2) until the locking ramp (25 ) pinch the cable, thus retaining it in the groove (9), as shown in Figure 10.

The user then installs a carabiner (5) by engaging it in the hole (23) of the lever (16), as illustrated in FIG. 11. Then, he fixes his harness (3) to the carabiner, for example, via the mooring loops (4), as shown in Figure 12.

In the position illustrated in FIG. 12, the fall arrester (1) is blocked against any untimely descent downwards (BA) preventing the user from falling, but can be moved upwards (HA) by rotation upwards according to (R1) of the lever (16), as illustrated in FIG. 13. When climbing, the user pivots the lever (16) upwards (HA) along (R2) until the carabiner is in stop on the stops (20a) and (20b) of the flanges. In this intermediate position, the lever prevents any possibility for the cable to leave the groove (9) and as soon as the lever is released, the latter pivots again downwards along (R1), which causes the cable to be blocked. Anti fall. When descending, the weight of the fall arrester (1) and the spring allow the lever (16) to remain in abutment on the stops (20a) and (20b) of the flanges (12a) and (12b). Thus, the user can descend without intervening on the fall arrester (1). In the event of a sudden fall or descent, the lever (16) pivots downwards (BA) along (R1), while the locking ramp (25) pinches the cable (6).

From the above description, it can be seen that the fall arrester comprises a system of stops (20a, 20b) for the carabiner, a system of stops which limits the pivoting of the lever in an intermediate position when the user passes this lever. the position of closing to the open position. It is then impossible for the user to exceed this intermediate position, and it is then impossible for the cable to leave the retaining groove, the cam (10) being still engaged in the cable retaining zone, as appears in the figure 13. It will also be noted that the release (1 Sa, 15b) allows the carabiner (5) and therefore the lever (16) to move from the closed position to the intermediate position according to which the carabiner is supported on the two stops (20a, 20b). In the intermediate position of Figure 13, we see that there is a clearance (j) between the cable and the cam (10), which allows a free sliding both upwards (HA) and downwards (BA). However, as soon as there is a fall, the fall arrester (1) immediately returns to its locked position as illustrated in FIG. 12.

Furthermore, the fall arrester is advantageously metallic such as, for example, stainless steel. Let us add, as appears more particularly in FIGS. 6 and 8 illustrating the fall arrester in its extreme open position, that the length (L2) of the lever is such that its end (22) protrudes beyond the upper ramps (18a , 18b).

FIG. 14 represents an alternative embodiment according to which the lever (16) does not rub on the wall (11a) of the first flange (12a). For this purpose, there is provided a washer (210) disposed around the axis (21) between said lever (16) and the wall (11a), as shown in the drawing in the sectioned area.

Figures 15 and 16 are views illustrating an alternative embodiment according to which the locking ramp (25) comprises two locking projections, namely, an upper projection (250) and a lower projection (251). Furthermore, according to this variant, the lower ramp (17a, 17b) extends over a greater length than previously to extend beyond and above the horizontal plane (H). It should also be noted that an additional safety member is provided, consisting of a pivoting pawl (40) urged to close by a spring. Said pawl (50) being intended to condemn the untimely release of the belay support (6) by the passage (40).

Note also that in this variant there are provided additional locking means (51, 52, 53) for the lever (16) so that in the fully inverted position of the device as illustrated in FIG. 17 there is locking of said lever (16) in its extreme open position. For this purpose, there is provided a sliding rod (51) intended to slide freely in a hole (52) made in the lever, while in the locking position, the end of the rod, by its own weight, s' engages in a corresponding hole (53) made in the axis (21).

Of course, the invention is not limited to the embodiments described and shown by way of examples, but it also includes all the technical equivalents and their combinations.

Claims (7)

Movable fall arrester for belay support (6) such as a cable or rope, of the type comprising a retaining groove (9) with axis (YY '), in which said belay support is retained by means of a cam (10), characterized in that the ramp is integral with a pivoting lever (16) between an open position and a closed position, and the free end of which comprises a hole (23) intended to receive a carabiner ( 5), while a stop system (20a, 20b) for the carabiner limits the pivoting of the lever in an intermediate position when moving from the closed position to the open position. Fall arrester according to claim 1, characterized in that the retaining groove (9) is produced by the wall (11a) of a main flange (12a) and comprises a secondary flange (12b) constituted by a wall (11b), while that the lever (16) is pivotally mounted between the two flanges (12a, 12b). Fall arrester according to claim 2, characterized in that it comprises a passage (40) longitudinal and parallel to the axis (YY ') of the groove (9), said passage being limited laterally by, on the one hand, the first border (13a) of the main flange (12a) and, on the other hand, the first border (13b) of the second flange. Fall arrester according to claim 3, characterized in that the second edges (14a, 14b) include a clearance (15a, 15b) allowing the lever (16) to move with its carabiner (5) and delimiting the stops (20a, 20b) defining the intermediate position of the lever. Fall arrester according to claim 4, characterized in that the second lateral border of each of the flanges (14a, 14b) comprises a succession of two ramps, a lower ramp (17a, 17b) set back with respect to an upper ramp (18a, 18b ) to form the clearance (15a). The lower ramp is circular with radius (R1) centered on the axis (XX '), while the upper ramp is circular with radius (R2) centered on the axis (XX'), knowing that the radius (R2) of said upper ramp is greater than the radius (R1) of said lower ramp, the clearance (15a, 15b) formed by the lower recessed ramp, is limited upwards by the stops (20a, 20b) arranged radially and substantially in the horizontal plane (H) passing through the axis (XX ') pivoting of the lever (16). Fall arrester according to any one of the preceding claims, characterized in that the cam (10) consists of a locking ramp (25) extended by an unlocking ramp (26). Fall arrester according to any one of the preceding claims, characterized in that the width of the lever (16) is such that it projects beyond the upper ramps (18a, 18b) when the lever is in the extreme open position.

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