Fire escape – ladder – or scaffold – Torso harness – Strand-engaging – with descent retarder
Patent
1990-10-31
1991-10-08
Chin-Shue, Alvin C.
Fire escape, ladder, or scaffold
Torso harness
Strand-engaging, with descent retarder
182193, 188 655, A63B 2900
Patent
active
050545779
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The invention relates to a self-jamming descender with two jamming positions for a user to descend along a rope, and comprising : to an articulation spindle, perpendicular to the first flange, mounted around the spindle in a parallel plane to the base flange, to form a jamming device with two jamming positions of the rope, which is wound in an S in the guide grooves of the two pulleys, unjamming taking place in an intermediate position of the operating lever, being interposed in a transverse gap, said second flange being retractable to allow the rope to be wound on the pulleys, which the rope is pressed by a boss of the second pulley in a first jamming position of the operating lever.
A descender of this kind is known from the document FR-2,451,752 in which the second pulley is equipped with two bosses cooperating with the first pulley to form a jammer with two jamming positions, when the pivoting operating lever is alternately in two extreme positions. It can be noted that the jamming function of each boss is always exerted on the same intermediate strand of the rope, arranged between the two pulleys. The movement of the operating lever between the two jamming positions is in the order of a quarter-circle, and the manual unjamming action to the intermediate position of the operating lever requires great effort.
SUMMARY OF THE INVENTION
The object of the invention consists in improving the reliability and grip of a self-jamming descender with two jamming positions.
The descender according to the invention is characterized in that the pivoting support plate comprises opposite from the operating lever, a jamming cleat separated from the second pulley by a space for the rope to pass, and that the first pulley is provided with a second braking surface, against which the rope is pressed by the jamming cleat when the operating handle is moved to a second jamming position.
The articulation spindle of the mobile support plate is eccentric with respect to the fictitious center of the second pulley, so as to increase the jamming torque of the rope when the operating lever is urged to the first jamming position.
The space for the support plate to pass between the second pulley and the jamming cleat has passing through it two adjacent strands of a loop of the rope, which is wound on the first pulley.
When the descender is in operation, the right-angle position of the operating handle makes it easier for the user to grip and actuate when movement takes place to the intermediate unjamming position.
The descender is hooked onto the harness by means of a karabiner and connecting strap. The karabiner is positioned in oblong openings of decreasing cross-section provided at the ends of the flanges.
BRIEF DESCRIPTION OF THE DRAWINGS
Other advantages and features will become more clearly apparent from the following description of an illustrative embodiment of the invention, given as a non-restrictive example only and represented in the accompanying drawings, in which :
FIG. 1 shows an elevational view of the descender according to the invention, represented with the second flange in the separated position for the rope to be wound onto the pulleys ;
FIG. 2 is an identical view to FIG. 1, in the intermediate unjamming position of the operating handle, the second flange not being represented for greater clarity ;
FIG. 3 and 4 are identical views to FIG. 2, the descender being represented respectively in a first and in a second jamming position of the handle ;
FIG. 5 shows the descender in the rest position during transport ;
FIG. 6 represents the first base flange equipped with the first pulley and the articulation spindle ;
FIG. 7 is a profile view of the descender in the closed position of the second flange ;
FIG. 8 shows the mobile support plate comprising the operating lever, the second pulley and the jamming cleat.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the figures, a self-jamming descender 10 with two jamming positions, comprises a pair of pulleys 12, 14, housed in a transverse gap
REFERENCES:
patent: 4596314 (1986-06-01), Rogelja
Petzl Paul
Petzl Pierre
Chin-Shue Alvin C.
Petzl S.A.
LandOfFree
Self-jamming descender for a rope with two jamming positions does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Self-jamming descender for a rope with two jamming positions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Self-jamming descender for a rope with two jamming positions will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-251815