초록 ▼

A cylindrical oil-filled casing (2, 3, 5) has an input shaft (12) on which are mounted a pair of braking rings (17, 26) which are allowed limited axial and circumferential movement with respect to one another. The ring (26) is driven by the shaft and drives the other ring (17) through a circle of an

A cylindrical oil-filled casing (2, 3, 5) has an input shaft (12) on which are mounted a pair of braking rings (17, 26) which are allowed limited axial and circumferential movement with respect to one another. The ring (26) is driven by the shaft and drives the other ring (17) through a circle of angularly-spaced, spring-biassed balls (28) mounted in tear-drop shaped recesses in the opposed faces of the rings (17, 26). Each ring has a frusto-conical braking rim extending parallel to a frusto-conical braking surface (8, 9) provided on the casing part (5). The rims of the rings (17, 26) have angularly-spaced, shallow, chordal segments removed to provide recesses which, during rotation of the shaft (12), pump oil between the braking surfaces of the rings and the casing, to form hydraulic cushions therebetween. Reversal of the shaft torque causes the balls (28) to force the rings (17, 26) apart and into braking engagement with the casing to check rotation of the shaft. The pumping action of the recesses diminishes during braking so that the cushions collapse and do not impair braking.

대표청구항 ▼

A mechanism for abruptly checking the motion of a rotating input shaft comprising: an oil-filled casing; two rings which are axially and angularly displaceable with respect to one another mounted coaxially within said casing; braking surfaces provided on respective rims of said rings and lying on re

A mechanism for abruptly checking the motion of a rotating input shaft comprising: an oil-filled casing; two rings which are axially and angularly displaceable with respect to one another mounted coaxially within said casing; braking surfaces provided on respective rims of said rings and lying on respective frusto-conical surfaces; opposed braking surfaces provided on the casing and facing those of the rings, the braking surfaces of the casing also lying on frusto-conical surfaces which are complementary and parallel to those of the rings; resilient means acting to urge the two rings apart; a thrust-transmitting assembly positioned between the rings and composed of balls located in a circle of spaced pockets providing respective camming surfaces; and a series of circumferentially-spaced recesses provided on at least one of said braking surfaces and dividing it into circumferentially spaced arcuate braking zones, each of said recesses converges towards at least one of said braking zones flanking it.