Self-braking belay device for a rope

Abstract

The present invention relates to a device comprising a kinetic braking mechanism, in which device there is a pre-braking step prior to the rope passing through said kinetic braking mechanism. As such, the device comprises a casing that has an inlet hole (6) and an outlet hole (7) for the corresponding rope (8), and inside which casing a pulley (9) is mounted so that the rope (8) passes through forming a constrictor knot on itself, such that once the rope has passed through this mechanism, it passes over a conventional centrifugal braking mechanism, which is secured to the side of the device casing, in a second step.

Description

[0001] DESCRIPTION

[0002] Self-braking rope descender.

[0003] TECHNICAL SECTOR

[0004] The present invention relates to a self-braking rope descender.

[0005] The object of the invention is to provide a self-braking descender device with a structure that allows drastically reducing the heating of its internal structure during self-braking maneuvers, offering a device capable of functioning completely automatically, without the need to manipulate the safety rope during the descent once the device is armed, with optimal heat dissipation.

[0006] The invention is therefore situated in the field of rescue and salvage devices by means of descending along ropes.

[0007] BACKGROUND OF THE INVENTION

[0008] In the practical application of the invention, self-braking mechanisms for ropes are known, consisting of a housing in which an entry hole and an exit hole are defined for the descent rope, which is passed through an internal pulley whose axis is fixed to a centrifugal brake mechanism, in which two or more shoes participate that tend to expand radially by the centrifugal force caused by the advance of the rope in the rotation of the pulley and consequent rotation of the common axis of the centrifugal brake, so that at low speeds said brake mechanism remains retracted, while when the rope moves at a certain speed the rotation of the mechanism causes the automatic expansion of its brake elements by the inertia to which they are subjected, pressing internally on the housing in drum functions, causing its braking.

[0009] This mechanism presents the problem that a large part of the downward energy is transformed into heat in the centrifugal braking mechanism, forcing the use of large braking elements, and potentially causing malfunctions, such as a decrease in braking capacity, or total blockage of the mechanism if it overheats, requiring the design of larger equipment with greater heat dissipation capacity, which results in greater weight and volume, and higher manufacturing costs.

[0010] EXPLANATION OF THE INVENTION

[0011] The self-braking rope descender proposed by the invention fully and satisfactorily solves the problem described above, based on a simple but highly effective solution.

[0012] To this end, starting from the conventional structure of this type of device, the invention provides that the device additionally includes a mechanism that defines a pre-braking stage for the rope, before it accesses the conventional kinetic braking mechanism, which allows reducing the energy that the kinetic brake must absorb, which directly results in the heat generated in the brake, extending its useful life and avoiding erroneous operations such as its decrease in effectiveness, offering a smoother, safer and more uniform automatic operation.

[0013] More specifically, the pre-braking stage and main body of the device consists of a casing on one side of which the kinetic braking mechanism is fixed, a casing that includes an entry hole and an exit hole for the rope on its upper area, as well as lower appendages equipped with a hole for the passage of the corresponding safety carabiner, inside which a pulley is mounted over which the rope runs describing a constricted loop that causes the rope to brake by friction on it, thus absorbing part of the energy needed to brake the device.

[0014] Based on this structure, the pre-braking stage absorbs part of the energy required in the kinetic brake of the device, thus reducing the heat generated in said main braking mechanism, so that the energy of the pre-braking stage is absorbed mainly by the rope when applied by means of a constricted loop that generates friction on the rope itself instead of on the casing of the device, which greatly reduces the heating of the descender and also allows reducing the dimensions of the kinetic brake, all of which results in lower manufacturing costs for the same level of safety.

[0015] DESCRIPTION OF THE DRAWINGS

[0016] To complement the description that follows and to aid in a better understanding of the characteristics of the invention, according to a preferred embodiment thereof, a set of drawings is included as an integral part of said description, in which, for illustrative and non-limiting purposes, the following has been represented:

[0017] Figure 1 shows a perspective view of a self-braking rope descender made in accordance with the object of the present invention.

[0018] Figure 2 shows an opposite perspective view of the set in Figure 1.

[0019] Figure 3 shows a view similar to that of Figure 1, but in which the centrifugal braking mechanism appears without the housing or drum that carries the brake shoes, to allow a clearer view of the structure of the device that is linked to the rope.

[0020] Figure 4 shows a side perspective view of the device in Figure 3.

[0021] Figure 5 shows an exploded view of the device.

[0022] Figure 6 shows a view similar to that of Figure 3, but in which the corresponding safety rope is applied to the device.

[0023] Figure 7 shows, finally, a detail of the way to apply the constricted loop on the pulley of the pre-braking stage that constitutes the main body of the device.

[0024] PREFERRED EMBODIMENT OF THE INVENTION

[0025] In view of the figures described, it can be observed that the device of the invention is constituted from a main casing in which two parallel plates (1-1') are defined that extend into a lower sector or appendage (2) provided with a hole (3) for the passage of the carabiner or safety element associated with the climber's harness, including some side separators (4-4'), as well as an upper sector (5) provided with an entry hole (7) and an exit hole (6) for the corresponding rope (8), these elements being fixed by means of screws (11), rivets or by any other conventional means.

[0026] Inside the housing is mounted a pulley (9) that defines a pre-braking stage for the rope (8), which is applied to this pulley defining a constricted loop, as shown in figure 7, where the rope once wound around the perimeter of the pulley, it is passed over itself to reverse its trajectory and is wound a second time around the pulley before exiting through the exit hole, which causes the rope in its movement to tend to constrict itself, generating a friction that causes a first braking stage for the rope which once it has left this pre-braking stage it is passed through a conventional kinetic braking mechanism shown partially in figure 6.

[0027] This kinetic braking mechanism includes an annular housing (12) fixed to one of the plates (1). The housing has an inlet hole (7') and an outlet hole (6') on its upper surface and contains an internal wheel (13) through which the rope (8) passes. The wheel (13) has a peripheral rim with a constricted toothed channel (14) in which the rope (8) tends to wedge itself. The wheel (13) is attached to the disc that carries the brake shoes (16). The brake shoes are displaced radially by their own inertia or centrifugal force during their rotation against the inner surface of a drum (15), against the tension of an elastic element, such as a spring. This is all in accordance with the conventional and known structure of this type of braking mechanism.

[0028] In this preferred embodiment, the wheel (13) shares the pivot axis (10) with the pulley (9), with said pivot axis (10) extending longitudinally to pass through the main housing, as well as the annular housing (12) of the kinetic braking mechanism. In other embodiments, the pivot axis of the pulley (9) may not coincide longitudinally with the pivot axis of the wheel (13), adopting a parallel arrangement with respect to its imaginary axis of symmetry.Based on this structure, and as previously stated, the rope (8) through the constricted loop generates friction as it slides within the pulley (9), creating a pre-braking stage that significantly reduces the energy required to brake the rope within the centrifugal braking mechanism attached laterally to the device. This results in reduced heat generation in the mechanism, allowing for a device that, in addition to operating fully automatically (meaning the user does not need to manipulate the safety rope as it moves at the appropriate speed during descent), also features a smoother, more homogeneous, controlled, and safe sliding motion, enabling the use of smaller centrifugal brakes.

Claims

CLAIMS 1 a- Self-braking rope descender, characterized in that it is constituted from a main casing in which two parallel plates (1-1') are defined, extending into a lower sector or appendage (2) provided with an opening (3) for the passage of the carabiner or safety element associated with the safety harness, including lateral separators (4-4'), as well as an upper sector (5) provided with an entry hole (7) and an exit hole (6) for the corresponding rope (8), a body in which a pulley (9) is mounted for the passage of the rope (8) forming a constricted loop on it, a kinetic braking mechanism that is fixed laterally on one of the plates (1), in which an annular casing (12) participates, provided in its upper area with an entry hole (7') and an exit hole (6') for the rope (8), internally including a wheel (13) through which the rope (8) is passed,The wheel (13) is attached to a carrier element with two or more shoes (16) that are radially displaceable due to their own inertia or centrifugal force during their rotation against the inner surface of a drum (15) against the tension of an elastic element. 2 a - Self-braking rope descender, according to claim 1 a , where the wheel (13) has a perimeter edge in which a constricted toothed channel (14) is defined for wedging the rope (8). 3 a - Self-braking rope descender, according to claim 1 a , where the second housing (12) is attached to the plate (1) by means of rivets or screws (11). 4 a - Self-braking rope descender, according to claim 1 a , where the main casing has a detachable character, by means of screws (11). 5 a - Self-braking rope descender, according to claim 1a , wherein the wheel (13) shares the pivot axis (10) with the pulley (9), said pivot axis (10) extending longitudinally to pass through the main housing, as well as the annular housing (12) of the kinetic braking mechanism. 6 a - Self-braking rope descender, according to claim 1 a , where the axis of rotation of the wheel (13) adopts a parallel arrangement with respect to the imaginary axis of symmetry of the axis of rotation of the pulley (9).

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