EP1380320B1 - Fall protection follower device along a fixed rope - Google Patents

Abstract

The following fall-prevention device includes a fixed safety cord (12) equipped with a restraint system comprising an arm support articulated on a first axis (24) between active blocking and release positions. The device also includes a cylindrical roller (28) and a mechanical coupling arranged between a body of a roller drive device (33) and the arm support so as to occupy a disconnected position or a coupled position. The peripheral surface of the roller has a number of barbs (32) for enabling rotation of the roller in the direction of the descent, and a slip on the safety cord. The body (16) of the fall precentrion device comprises a U-shaped rectilinear chute for passage of the cord, with the chute having holes for the passage of a fastener attachable to the cord.

Description

Technical field of the invention

• un corps équipé d'un système de retenue agencé pour occuper soit une position active de blocage en cas de chute, soit une position inactive de déblocage autorisant la progression de l'utilisateur le long de la corde dans le sens de la montée, ou dans le sens opposé lors d'une descente contrôlée, ledit système de retenue comportant un bras support articulé sur un premier axe du corps, un galet en forme de roue cylindrique montée à rotation libre sur un deuxième axe solidaire du bras support, et un accouplement mécanique centrifuge agencé entre un organe d'entraínement du galet et le bras support de manière à occuper une position débrayée ou une position embrayée,
• et des moyens d'attache pour la liaison du corps à un baudrier d'assurance de l'utilisateur.

The invention relates to a follower anti-fall device used with a fixed safety rope, and comprising:

• a body equipped with a retaining system arranged to occupy either an active blocking position in the event of a fall, or an inactive unlocking position allowing the progression of the user along the rope in the direction of the climb, or in the opposite direction during a controlled descent, said retaining system comprising a support arm articulated on a first axis of the body, a cylindrical wheel-shaped roller mounted for free rotation on a second axis integral with the support arm, and a mechanical coupling centrifugal arranged between a drive member of the roller and the support arm so as to occupy a disengaged position or an engaged position,
• and attachment means for binding the body to a user's insurance belt.

State of the art

During normal use of ascent or descent, fall arrest devices follow the progression of the person along the rope without generating blocking. The person is free to move without any intervention manual release of the fall arrest device. The blocking occurs only in case of fall.

The restraint system of known fall arrest devices generally includes a pivoting lever having at one end an attachment ring for the connection to a shoulder belt, and at the opposite end a locking cam of the rope. Such The arrangement behaves like a cleat which may prevent blocking if the user were to grip the lever in the event of a fall.

WO 00/24471 relates to a locking device bidirectional for a fall arrest apparatus, comprising a locking member equipped with two cams actuated independently by an organ of common blockage in response to a sudden change in weight. The blocking of each of the cams depends on the inclination of the rope relative to the chassis of the device.

US 4923037 discloses a fall arrest device having a system of restraint consisting of an articulated support arm, which is equipped with a wheel cylindrical mounted free rotation, and a centrifugal mechanical coupling arranged in a ratchet. The periphery of the wheel has a series of teeth constituting a pinion causing rotation of the wheel by friction with the cable. The radial direction of the teeth does not allow to obtain a functioning optimum fall arrest system. In addition, to insert the vertical lifeline in the fall arrest device, it is necessary to make use of a U-shaped articulated, and to rotate outward, which complicates maneuvers.

Object of the invention

The object of the invention is to provide a fall arrest apparatus for a fixed rope, to obtain maximum safety for the user in the event of a fall, regardless of the inclination of the rope or a handling error of the device.

The fall arrest device according to the invention is characterized in that the surface roller device is provided with a plurality of pins arranged for generate a rotation of the roller in the direction of the descent, and a slip on the rope in the direction of the climb, and that the body has a chute rectilinear U-shaped for the passage of the rope, said chute having holes for the passage of fastening means.

During normal use of ascent or descent, mating is in the disengaged position, and the fall arrest device follows the progression of the person along the rope without any manual intervention to unblock the system restraint. Blocking occurs automatically in case of a fall, even if the user clings to the device. In this case, the coupling is in engaged position causing a strong pressure of the roller against the rope.

According to a preferred embodiment, the mechanical coupling is disposed inside the roller, and comprises at least one movable weight by centrifugal effect along a ramp as a function of speed or acceleration of the drive member of the roller. The weight is associated with a spring of return biasing the mechanical coupling in the disengaged position, the threshold when the centrifugal force is greater than the force return spring.

It is of course possible to use any other type of clutch device for locking the roller on the support arm at a predetermined speed.

• la masselotte est de forme cylindrique, et coopère en position embrayée avec un rebord cylindrique du bras support ;
• les moyens d'attache sont constitués par un mousqueton traversant des trous alignés du corps de l'appareil antichute ;
• le bras support est doté de moyens de sécurité destinés à limiter la course de pivotement dudit bras dans la position inactive de déblocage, et à empêcher la mise en place du mousqueton avant l'introduction de la corde dans la goulotte ;
• les moyens de sécurité comportent une butée solidaire du bras support, et ayant une extrémité équipée d'une protubérance ;
• les moyens de sécurité comportent un volet monté à pivotement sur un axe, et comprenant une ouverture oblongue à l'intérieur de laquelle se déplace un levier de commande solidaire du bras support, et une aile destinée à plaquer la corde au fond de la goulotte.

Other features may be used singly or in combination:

• the weight is of cylindrical shape, and cooperates in the engaged position with a cylindrical rim of the support arm;
• the attachment means are constituted by a carabiner through aligned holes of the body of the fall arrest device;
• the support arm is provided with safety means intended to limit the pivoting stroke of said arm in the inactive unlocking position, and to prevent the introduction of the carabiner before the introduction of the rope into the chute;
• the safety means comprise an abutment integral with the support arm, and having an end equipped with a protuberance;
• the security means comprise a flap pivotally mounted on an axis, and comprising an oblong opening inside which moves a control lever secured to the support arm, and a wing intended to press the rope at the bottom of the chute.

Brief description of the drawings

• la figure 1 est une vue en perspective de l'appareil antichute selon l'invention, lequel est installé sur une corde d'assurance après mise en place d'un mousqueton d'attache ;
• la figure 2 montre une vue éclatée en perspective de l'appareil antichute de la figure 1, l'accouplement mécanique étant montré en position débrayée à l'intérieur du galet ;
• la figure 3 est une vue de gauche de la figure 2, après démontage des masselottes ;
• la figure 4 représente une vue en élévation de l'appareil après ouverture du système de retenue pour le passage de la corde ;
• la figure 5 est une vue identique de la figure 4, et représente la position d'utilisation normale de montée ou de descente après mise en place du mousqueton ;
• la figure 6 est une vue de dessus de la figure 5 ;
• la figure 7 est une vue en coupe verticale de la figure 5 ;
• les figures 8 et 9 sont des vues en coupe selon les lignes 8-8 et 9-9 de la figure 7 ;
• la figure 10 montre une vue identique de la figure 7, l'appareil étant en position de blocage suite à une chute ;
• la figure 11 montre la position anti-ouverture de sécurité suite à la venue en butée du système de retenue contre le mousqueton ;
• la figure 12 est une vue en coupe de la figure 4, la butée se trouvant dans une position empêchant la mise en place du mousqueton ;
• la figure 13 est une vue en perspective d'une variante de réalisation à volet de sécurité ;
• la figure 14 est une vue identique de la figure 13 lors de l'ouverture du bras support pour la mise en place de la corde ;
• les figures 15 à 17 sont des vues partiellement arrachées de la figure 13, respectivement après mise en place de la corde, en position de fonctionnement normal, et en position de blocage.

Other advantages and features will emerge more clearly from the following description of an embodiment of the invention given by way of non-limiting example, and represented in the appended drawings in which:

• Figure 1 is a perspective view of the fall arrest device according to the invention, which is installed on a lifeline after installation of a carabiner attachment;
• Figure 2 shows an exploded perspective view of the fall arrest apparatus of Figure 1, the mechanical coupling being shown in the disengaged position within the roller;
• Figure 3 is a left view of Figure 2, after disassembly of the weights;
• Figure 4 shows an elevational view of the apparatus after opening the restraint system for the passage of the rope;
• Figure 5 is an identical view of Figure 4, and shows the normal use position rise or fall after installation of the carabiner;
• Figure 6 is a top view of Figure 5;
• Figure 7 is a vertical sectional view of Figure 5;
• Figures 8 and 9 are sectional views along the lines 8-8 and 9-9 of Figure 7;
• Figure 10 shows an identical view of Figure 7, the apparatus being in the blocking position following a fall;
• Figure 11 shows the anti-safety opening position following the abutment of the retaining system against the carabiner;
• Figure 12 is a sectional view of Figure 4, the stop being in a position preventing the introduction of the carabiner;
• Figure 13 is a perspective view of an alternative embodiment with safety flap;
• Figure 14 is an identical view of Figure 13 when opening the support arm for the establishment of the rope;
• Figures 15 to 17 are partially cutaway views of Figure 13, respectively after implementation of the rope, in the normal operating position, and in the locking position.

Description of two preferred embodiments

In FIGS. 1 to 12, a fall arrest device 10 is used for the safety of a person moving along a fixed 12 insurance rope. A carabiner 14 is hooked to the fall arrest device 10 so as to be connected to the harness, either live, either through an absorption lanyard.

During normal use of ascent or descent, the fall arrest device 10 follows the progression of the person along the rope 12 without generating blocking. The person is free to move without any intervention Manual release of the fall arrest device 10.

The fall arrest device 10 is composed of a rigid body 16 and a control system. mobile retainer 18 cooperating with the rope 12 to occupy either a position blocking function in the event of a fall, ie an inactive unlocking position in the direction of the climb, or in the opposite direction during a controlled descent.

The body 16, which is preferably metallic, comprises a straight trough 20 made of U shape for the passage of the rope 12, and a stirrup 22 for mounting a first axis 24 extending transversely to the direction of the chute 20. The upper part of the chute 20 is pierced by two holes 23 to allow the passage of the carabiner 14 attachment to the harness.

The retaining member 18 comprises a support arm 26 articulated on the first axis 24, and a wheel-shaped roller 28 mounted for free rotation on a second axis 30 integral with the support arm 26. The peripheral surface of the roller 28 is cylindrical, and is provided with a plurality of pins 32 each having an inclination predetermined with respect to the radial direction passing through the axis 30. A spring torsion (not shown) is threaded on the first axis 24 and urges the arm support 26 in the direction of the chute 20.

The roller 28 is provided with an internal drive member 33, pierced by an orifice 34 central cylindrical, which is traversed by a tubular bearing 36 introduced on the second fixed axis 30. Inside the roller 28 is in addition a mechanical coupling 38 formed by a pair of weights 40 cylindrical arranged between opposite ramps 42 of the organ 33 and a circular flange 44 of the support arm 26.

Each weight 40 is associated with a spring 46 in the shape of a pin intended for urging the mechanical coupling 38 to the disengaged position when the normal use of the fall arrest device 10. In this state of rest, the 40 flyweights are in a hollow of the drive member 33, in order to interrupt the mechanical coupling 38 between the roller 28 and the arm 26. The roller 28 is then rotated by the friction of the rope 12, while the support arm 26 is in the inactive position allowing the device fall arrest 10 to follow the progress of the user on the ascent or descent.

The restoring force of the springs 46 defines the coupling threshold as a function of the speed or acceleration of the drive member 33 of the rotary roller 28. In the event of a fall, the abrupt rotation of the roller 28 on the axis 30 causes the displacement of the weights 40 by centrifugal effect to the engaged position. This movement is effected against the restoring force of the springs 46, and causes jamming of the weights 40 between the flange 44 and the body 33. The mechanical coupling in the engaged position thus makes the roller 28 secured to the support arm 26, so as to form a cleat wedge capable of pivoting about the first axis 24, and blocking the fall by blocking the rope 12.

The pivoting support arm 26 is equipped with a stop 48 intended to cooperate with the carabiner 14 to limit the pivoting stroke of the arm 26 in the inactive unlock position. The response time of the support arm 26 pivoting is thus reduced to the minimum to obtain the blocking in case of fall. The end of the stop 48 is provided with a protuberance 49 intended for intercalate between the two holes 23 of the body 16 to prevent the establishment carabiner 14 before the introduction of the rope 12.

The operation of the fall arrest device 10 according to FIGS. 1 to 12 is the next:

In Figures 1 to 12, the fall arrest device 10 is shown in the position opening for the installation of the rope 12 in the trough 20. The system of retainer 18 is spaced at the maximum of the chute against the force of return of the torsion spring. Rope 12 is hooked to an anchor fixed upper, for example a plate or a stud. The protuberance 49 of the stop 48 closes the two holes 23, which prevents the introduction of the carabiner 14 before the introduction of the rope 12 into the chute 20.

In FIGS. 5 to 7, the position of normal use of the fall arrest device 10 for the climb (arrow F1) or the descent (arrow F2), is obtained after releasing the restraint system 18 and setting up the carabiner 14 in the holes 23. The pins 32 of the roller 28 come into contact with the rope 12 under the action of the torsion spring, but without causing blockage. The fall arrest device 10 tracks the progress of the person along the rope 12, the mechanical coupling 38 is permanently in the disengaged position. The person is free to move without any manual intervention of Unlocking the fall arrest device 10. During the descent (arrow F2), the roller 28 rotates clockwise under the effect of the friction of the rope 12 on the pins 32, and the weights 40 remain immobilized in the disengaged position under the action of the springs 46. The controlled braking of the roller 28 allows the device fall arrest 10 to be positioned above the user. At the climb (arrow F1), the roller 28 slides on the rope 12 by pivoting the arm assembly 26 and roller 28 about the first axis 24.

Referring to Figure 10 corresponding to a locking position on a fall of the user, the abrupt rotation of the roller and the drive member 33 in the clockwise subjects the weights 40 to a centrifugal force, which is higher and opposite to the restoring force of the springs 46. The weights 40 move on the ramps 42, which causes jamming weights 40 between the flange 44 and the drive member 33. The mechanical coupling is then in the engaged position, making the roller 28 secured to the support arm 26. The assembly constitutes a jamming cleat rotatable clockwise about the first axis 24, and blocking the fall by blocking the rope 12. Unblocking the weights 40 intervenes by a manual action of the operator to maintain the roller 28 against the rope 12, and by raising the body 16 by a few centimeters.

In FIG. 11, it can be seen that in the position of normal use of the device 10, the stop 48 is in abutment against the carabiner 14 to limit the arm pivoting stroke 26 in the inactive unlocking position. The Response time for blocking is thus reduced in case of a fall.

According to the development of the invention illustrated in FIGS. 13 to 17, the stop 48 is replaced by a security flap 50, which is arranged to fill the same functions of the abutment 48 of the preceding Figures 1-12, in addition to a positioning function of the rope 12 at the bottom of the chute 20 before the introduction of the carabiner 14 in the holes 23.

The safety flap 50 is pivotally mounted on an axis 52, and comprises a oblong aperture 54 inside which moves a lever of control 56 secured to the support arm 26. The opening 54 has a double angled ramp for moving the flap 50 according to the pivoting movement of the arm 26. The flap 50 further comprises a wing 58 intended to press the rope 12 at the bottom of the chute 20.

The operation of the safety shutter 50 according to FIGS. 14 to 17 is the next :

In Figure 14 corresponding to the establishment of the rope 12, the support arm 26 of the fall arrest device 10 is in the open position, and the flap 50 driven by the control lever 56, closes one of the holes 23. In this position, the carabiner 14 can not be introduced into the holes 23, and the passage of the rope 12 in the chute 20 is cleared.

In FIGS. 15 and 16, the operator releases the pivoting arm 26 after the introduction of the rope 12 into the chute 20. The wing 56 of the shutter 50 comes correctly position the rope 12 at the bottom of the chute 20. The spacing of the flap 50 thus allows the introduction of the carabiner 14 into the holes 23, and the rope 12 is positioned between the chute 20 and the carabiner 14 in the normal operating position.

In FIG. 17 corresponding to the blocking position of the arm 26 following a drop, the movement of the lever 56 in the opening 54 allows the flap 50 to keep the same position in Figure 16, so as not to interfere with the kinematic blocking.

Claims (8)

1. A follower fall arrest device used with a fixed safety rope (12), and comprising:

   a body (16) equipped with a securing system (18) arranged to occupy either an active locking position in case of a fall or an inactive unlocking position enabling the user to progress along the rope (12) in the ascending direction, or in the opposite direction when performing a controlled descent, said securing system (18) comprising a support arm (26) articulated on a first spindle (24) of the body (16), a roller (28) in the form of a cylindrical wheel mounted rotating free on a second spindle (30) securedly attached to the support arm (26), and a centrifugal clutch mechanism (38) arranged between a drive member (33) of the roller (28) and the support arm (26) so as to occupy a disengaged position or an engaged position,

   and attachment means for connecting the body (16) to a safety harness worn by the user,

   characterized in that

   the peripheral surface of the roller (28) is equipped with a plurality of studs (32) arranged to cause rotation of the roller (28) in the descending direction, and sliding on the rope (12) in the ascending direction,

   the body (16) comprises a straight U-shaped channel (20) for passage of the rope (12), said channel having holes (23) for passage of the attachment means.
2. The fall arrest device according to claim 1, characterized in that the clutch mechanism (38) is arranged inside the roller (28) and comprises at least one flyweight (40) movable by centrifugal effect along a ramp (42) according to the speed or the acceleration of the drive member (33) of the roller (28).
3. The fall arrest device according to claim 2, characterized in that the flyweight (40) is associated with a return spring (46) urging the clutch mechanism (38) to the disengaged position, the coupling threshold being reached when the centrifugal force is greater than the return force of the spring (46).
4. The fall arrest device according to claim 3, characterized in that the flyweight (40) is cylindrical in shape and cooperates in the engaged position with a cylindrical rim (44) of the support arm (26).
5. The fall arrest device according to claim 1, characterized in that the attachment means are formed by a karabiner (14) passing through the holes (23) of the body (16).
6. The fall arrest device according to claim 1, characterized in that the support arm (26) is equipped with safety means (48, 50) designed to limit the pivoting travel of said arm in the inactive unlocking position and to prevent the karabiner (14) from being fitted before the rope (12) has been inserted in the channel (20).
7. The fall arrest device according to claim 6, characterized in that the safety means comprise a stop (48) securedly attached to the support arm (26) and having one end equipped with a protuberance (49).
8. The fall arrest device according to claim 6, characterized in that the safety means comprise a flap (50) pivotally mounted on a spindle (52) and comprising:

   an oblong opening (54) inside which an operating lever (56) moves securedly attached to the support arm (26),

   and a wing (58) designed to press the rope (12) against the bottom of the channel (20).

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