GB959466A - Improvements in or relating to machinery for laying and recovering submarine cable - Google Patents

Abstract

959,466. Winches. POSTMASTER GENERAL. April 30,1962 [May 4, 1961], No. 16254/61. Heading B8B. In a cable winding device for cable laying and recovering, the back-tensioning mechanism such as a sheave 19, Fig. 1, is drivingly coupled to the main winding drum 1 through a free-wheel device 8, 9 and through a slipping device such as an epicyclic gear 20 permitting control of the torque transmitted to the sheave 19. In operation, during cable laying, the cable 3 passes from the cable tank, once round the sheave 19 and then makes several turns round the main drum 1 before passing through ancillary laying equipment. In this direction of rotation as shown by arrows 36 the interconnecting shafts 5, 7 are so driven that the freewheel device 8, 9 does not transmit a drive to the sheave 19 which is braked by a band brake 22 operating on the housing 21 of the epicyclic gear. A pawl 13 engaging the freewheel 9 prevents its reverse rotation during the braking operation. During cable recovery the direction of rotation of the drum 1 is reversed and the sheave 19 is driven through the freewheel 8, 9 and epicyclic gear 20, the speed and torque being controlled by adjustment of the brake 22. A measurement of the torque transmitted may be obtained through a meter 30, Fig. 2 (not shown), adapted to measure the torque on a mounting plate for the brake 22 and which may be adapted to control the braking. The cable 3 is pressed into contact with the sheave 19 by means of a jockey roller 32 on one arm of a double arm lever 33 which is loaded by a weight 35. In modifications the epicyclic gear may be replaced by a magnetic clutch and the sheave 19 may be replaced by endless track gripping devices.