Patent ID: 6719275
Filing Date: 2004-04-13
Classification: B63B,B63G,B66D

Abstract:
A method of applying a linear force to a cable, the method comprising the steps of:deploying and retrieving a cable in the form of a towed sonar array by deploying cable from a winch drum and winding cable onto a drum; passing the cable around a convex arcuate support surface; passing a flexible member around at least three relatively small pulleys, two of the pulleys being located on a chord of the support surface; and driving the flexible member by driving one of the small pulleys such that tension is created in the flexible member and tends to bias the member to bear against the cable passing around a portion of the support surface located between said two of the small pulleys and form a cable nip between the flexible member and the support surface; wherein the support surface is provided separately of the drum and when deploying the array an initial tension is provided to veer the cable from the winch drum; then, once the drag on the array is sufficient to pull the cable from the drum, the flexible member is permitted to run free; and then when the drag on the array reaches a level where the remaining coils of cable on the winch drum are subject to a compressive force capable of damaging the cable the flexible member provides drag on the cable to reduce the tension in the cable between the support surface and the winch drum.