Descent assist device for powered ascenders
A descent assist device for powered ascenders is discussed herein. In one embodiment, the descent assist device can include a base plate having a first guide surface, a capstan peg, a second guide surface, and a retention loop extending from the first guide surface to the second guide surface configured to retain a rope on the descent assist device. Where the angle of wrapping of the rope around the first guide surface and the capstan peg is constant during use and the angle of wrapping of the rope around the second guide surface is adjustable by the user of the device to increase or decrease the frictional drag of the rope.
1. A powered rope ascender operational in ascending and descending modes, comprising:
a reversible drive source;
at least one rotating rope pulling jaw, the jaw connected to the reversible drive source so as to be rotated in a first, ascending direction and a second, opposed descending direction, the at least one rotating rope pulling jaw having a plurality of forward sweeping rope gripping features when operated in the ascending direction;
a friction increasing descent assist device configured to provide a rope path having at least three guide surfaces around which a rope disposed in the rope path wraps angularly including a first, superior guide surface, a second laterally spaced capstan guide surface, and a third inferior guide surface,
wherein the first and third guide surfaces form superior and inferior ends of a retention loop, and the second guide surface is provided on a capstan peg that is laterally spaced from the retention loop, and
wherein the friction increasing descent assist device enhances operation of the powered rope ascender when operating in the descending mode.
2. The powered rope ascender of claim 1 , wherein the friction increasing descent assist device is positioned on the powered rope ascender in an inferior direction from the at least one rope pulling jaw when the powered rope ascender is in use.
3. The powered rope ascender of claim 1 , wherein the retention loop comprises a gate allowing a middle portion of rope to be engaged with the friction increasing descent assist device through the gate.
4. The powered rope ascender of claim 1 , wherein the retention loop ensures that a rope stays engaged within the friction increasing descent assist device regardless of whether a free end of the rope is arranged in an optimal rope entry path while descending.
5. The powered rope ascender of claim 1 , wherein the rope path provided for by the friction increasing descent assist device includes a rope wrap angle around the second guide surface that is greater than 90 degrees.
6. The powered rope ascender of claim 5 , wherein the rope wrap angle of the rope path is greater than 180 degrees.
7. The powered rope ascender of claim 5 , wherein the friction increasing descent assist device is configured to provide a sum of rope wrap angles around the guide surfaces that is greater than 360 degrees.
8. The powered rope ascender of claim 1 , wherein the friction increasing descent assist device enhances the operation of the powered rope ascender by reducing an amount of damage caused to a rope disposed in the rope path by the forward sweeping rope gripping features when operated in the descending direction.
9. The powered rope ascender of claim 8 , further comprising a rope disposed in the rope path, engaged to the powered rope ascender and the friction increasing descent assist device, the rope having a diameter of 7 mm or less.
10. The powered rope ascender of claim 1 , wherein the friction increasing descent assist device enhances the operation of the powered rope ascender by slowing the rate of descent when a rope disposed in the rope path is located between the forward sweeping rope gripping features when operated in the descending direction.
11. The powered rope ascender of claim 10 , further comprising a rope engaged to the powered rope ascender and the friction increasing descent assist device, the rope having a diameter of 7 mm or less.
12. A descent assist device for use with a powered ascender comprising:
a rope;
a base plate;
a first guide surface located on a superior portion of the base plate;
a capstan peg laterally spaced from the first guide surface on the base plate, the capstan peg including a second guide surface;
a third guide surface located on the base plate in an inferior direction from the first guide surface; and
a retention loop extending from the first guide surface to the third guide surface and substantially fixed with respect to the base plate, the retention loop being configured to retain the rope on the descent assist device;
wherein an angle of wrapping of the rope around the first guide surface and the second guide surface is constant during use and the angle of wrapping of the rope around the third guide surface is adjustable by the user of the device to increase or decrease the frictional drag of the rope.
13. The descent assist device of claim 12 , wherein the angle of wrap of the rope around the first guide surface is approximately 90°, the angle of wrap of the rope around the second guide surface is greater than 180° and the angle of wrap around the third guide surface is at least 90°.
14. The descent assist device of claim 12 , wherein when the descent assist device is used with a powered ascender descending the rope, the rope is wrapped around the first guide surface, the second guide surface, and the third guide surface.
15. The descent assist device of claim 14 , wherein when the descent assist device is used with the powered ascender ascending the rope, the rope is disengaged from the descent assist device.
16. The descent assist device of claim 12 wherein the descent assist device is configured to prevent rope slippage when the powered ascender is used to descend the rope.
17. The descent assist device of claim 12 , wherein the retention loop comprises a gate allowing a middle portion of the rope to be engaged with the descent assist device through the gate.
18. A descent assist device for use with a powered ascender comprising:
a rope;
a base plate;
a first guide surface located on a superior portion of the base plate;
a capstan peg laterally spaced from the first guide surface on the base plate, the capstan peg including a second guide surface;
a third guide surface located on the base plate in an inferior direction from the first guide surface; and
a retention loop having a first end and a second, opposed end that are each coupled to the base plate, the retention loop being configured to retain the rope on the descent assist device,
wherein an angle of wrapping of the rope around the first guide surface and the second guide surface is constant during use and the angle of wrapping of the rope around the third guide surface is adjustable by the user of the device to increase or decrease the frictional drag of the rope.
19. The descent assist device of claim 18 , wherein the retention loop extends from the first guide surface to the third guide surface.
20. The decent assist device of claim 18 , wherein the angle of wrap of the rope around the first guide surface is approximately 90°, the angle of wrap of the rope around the second guide surface is greater than 180° and the angle of wrap around the third guide surface is at least 90°.
21. The descent assist device of claim 18 , wherein when the descent assist device is used with a powered ascender descending the rope, the rope is wrapped around the first guide surface, the second guide surface, and the third guide surface.
22. The descent assist device of claim 21 , wherein when the descent assist device is used with the powered ascender ascending the rope, the rope is disengaged from the descent assist device.
23. The descent assist device of claim 18 wherein the descent assist device is configured to prevent rope slippage when the powered ascender is used to descend the rope.
24. The descent assist device of claim 18 , wherein the retention loop comprises a gate allowing a middle portion of the rope to be engaged with the descent assist device through the gate.