Abstract: The mechanism has at least one carrier sprocket wheel (18-19) fixed on a horizontal shaft (15) mounted on the body of a grab (4) with pivoting fingers. An apparatus (14) for actuating the pivoting fingers connected to the shaft allows them to open and close to take up or, alternatively, release the absorbent unit. Drive chain wheels (25-26) allow the portions (20-21) of a chain supporting the carrier pulley (18-19) to be moved, either in synchronism to move the absorbent assembly or with a differential movement to actuate the pivoting fingers of the grab (4). A single differential pinion apparatus (31-32) allows the two kinds of movement to be carried out.The invention can be applied particularly to the control and emergency shutdown of pressurized water nuclear reactors.

Abstract: Device for the remote coupling and uncoupling of two elements of great length disposed coaxially and end to end, comprising an internal actuating sleeve (14) mounted for rotation on one of the elements (1, 5) and rigidly connected to a rod (10, 67) comprising, at its end, an actuating member (12), the rotation of which enables the coupling and the uncoupling to be effected by spacing apart or release of resilient members (8, 9) assuring the junction of the two elements (1, 5). A pin (17) is disposed transversely at the end of the assembly consisting of the internal sleeve (14) and the rod (10, 67), opposite to the end carrying the actuating member (12). An external sleeve (28) of larger diameter than the diameter of the internal sleeve (14) remaining in a fixed position, whereas the two elements (1-5) are displaced in the direction of their axis, comprises slots (45, 47) in which the pin (17) can engage.

Abstract: An automatic grapple comprising a hollow body and a slide suspended by a maneuvering cable with axially spaced portions to transform the relative movement of the slide to a displacement of gripping arms for engaging an object to be seized. The slide carries a locking member having variable orientation modified in a lower position of the slide. The position of extension or retraction of the arms is controlled by the axially spaced portions which have different diameters. The relative position of these portions is determined to permit rotation of the locking member only if the arms can be engaged in the object to be seized or is totally disengaged therefrom.