Abstract: A rope clutch having a plurality of apertured pivoted plates which grip or release a rope passing through their apertures according to the angle they make to the rope, has a mechanism for initiating release of the rope which includes a variable toggle linkage.

Abstract: A gripping device for releasably gripping a rope-like member comprises a pair of rope-engaging members defining a pair of opposite, mutually spaced rope engaging surfaces defining a rope passageway therebetween. The rope engaging surfaces are mounted in a frame so as to be moveable in relation to each other such that a force applied to the rope engaging surfaces and acting in one direction of the rope passageway will tend to move the rope engaging members closer to each other towards a locking position, while a force applied to the rope engaging surfaces and acting in the opposite direction of the rope passageway will tend to increase the spacing of the rope engaging surfaces and to move the rope engaging members towards a releasing position. At least one of the rope engaging members is connected to an operating handle by means of a lost motion connection. When the operating handle is moved from an inactive position to an active position the rope engaging members are moved to their releasing position.

Abstract: A method and apparatus for isolating electric power lines includes an insulator assembly to which is pivotally connected two line clamps. After the clamps clamp to the wire, the wire is cut so that the insulator isolates the line. In one form the clamping surfaces are curved in the longitudinal direction to make up for the loss of line length due to the elongation of the assembly under line tension. Cut-out assemblies for fuse and disconnect purposes are readily applied to the assembly by a lineman standing on the ground below.

Abstract: A clamping device comprises a holder in which an actuation arm is movable in a longitudinal directions. A fixed clamping jaw is carried by the holder and a movable clamping jaw is arranged within the holder opposite to the fixed clamping jaw and it is supported by at least two longitudinally spaced lever members which have a first pivotal connection to the holder, a second pivotal connection to the movable clamping jaw and a third pivotal connection to the actuator arm. An actuator is connected to the arm to move it backwardly and forwardly for opening and closing the jaws. The pivotal connecting points of the levers are chosen so that the pivotal points are disposed at substantially right angles to each other. The pivot pins are cylindrical hinge pins and the line between the pivotal connection of the lever to the jaw and to the fixed holder makes an angle of 45.degree. to the horizontal so that a larger distance between the points of support is possible.

Abstract: A wireline protector for protecting an electrical wireline used in a downhole drilling operation. During the operation of adding additional drill string members to the drill string, the electrical wireline is encased by and clamped within the wireline protector thereby guarding it against damage by any slippage of the slip members. The wireline protector includes an elongated section that is arranged to extend through the opening in the rotary table through which the drill string passes in such a manner so as not to interfere with the drill string and a support base connected substantially perpendicular to the elongated section. The elongated section has an elongated opening into which the portion of the wireline passing through the rotary table can be inserted so that it is substantially surrounded and guarded by the elongated section. After the wireline is inserted into this elongated section, a toggle lock clamping mechanism mounted on the support base acts to grip the wireline so as to retain it in place.

Abstract: A sail line stopper is provided for controlling the rate of movement of a sailing line prior to or subsequent to the locking of a line in a fixed position. The sail sheet stopper has a base with a channel formed therethrough. A plurality of closely spaced links are mounted for pivotal movement in the base and each of the links has an opening with the line openings forming a channel through which the line to be controlled is positioned. A handle is coupled to the links for controlling the pivotal movement of the links in the base. In a first position the handle aligns the openings allowing the line to move freely through the channel, and in a second position the openings are out of alignment thereby restricting the size of the channel through which the line moves to lock the line in the channel.

Abstract: A restraining device for controlling the movement of a loaded strop 3 comprises a power-driven reel for the strop and an associated pair of toggle-controlled clamping jaws 14, 15 pivoted at 16 and 17 respectively. The jaws are cross-connected by a link 18 and are loaded into the operative position to grip the strop 3 by a spring 25. The controlling toggle comprises links 28 and 30 pivoted together at 31, the link 28 being pivoted to the jaw 15 at 29 and the link 30 being pivoted to a fixed point 32. The link 30 carries a pivoted hand-lever 35 for releasing the toggle and formed with a hook portion 42 which engages with a corresponding hook portion 44 on the link 28 to lock the toggle in the released position to free the strop. The lever 35 can be released either manually or automatically by the piston 37 of a pneumatic cylinder 38. When the lever is released, the toggle moves to the braced position where it assists the action of the spring 25 in holding the jaws together to grip the strop.

Abstract: An instantaneously acting fall preventing device comprises a casing containing a locking mechanism, in the form of a series of rings which are adapted to co-operate with a retaining cord, and a connecting element for attachment to a harness or safety belt. The upper ring of the series of rings is provided with a lever which passes through a wall of the casing and extends into a guidance member for the connecting element. When the device is in the unlocked position, the lever is held against an abutment in the guidance member and said lever moves away from the abutment in the event of a fall to permit the rings to engage the cord and lock the device.

Abstract: An improved safety clamp device for use with movable platforms and the like includes a body member having a safety cable receiving cradle, a lever arm having a safety cable engaging portion, an elongate member carrying a pulley at either end, and a control arm. The control arm is in the form of a modified bellcrank having one arm portion pivotally connected to the body member, its apex connected to the elongate member and a pulley connected to a second arm portion. The lower end of the elongate member is rigidly connected to the movable platform. A drive or support cable passes on one side of the two pulleys on the elongate member and on the other side of the control arm pulley. The elongate member is maintained in a first position relative to the body member such that the safety cable engaging portion confronts but does not engage the safety cable when the drive or support cable is subjected to a predetermined tension.

Abstract: An improved safety clamp device for use with movable platforms and the like includes a body member having a safety cable receiving cradle, a lever arm having a safety cable engaging portion, the lever arm being pivotally connected to the body member and pivotally connected to an elongate bar member, and a modified bellcrank. The modified bellcrank has a first arm pivotally connected to the body member, a second arm pivotally coupled to a hoist line, and its apex pivotally connected to the elongate bar member. When the elongate bar member is in a first position relative to the body member, the safety cable engaging portion confronts but does not engage the safety cable. When the elongate bar member is in a second position relative to the body member, the safety cable engaging portion engages the safety cable thereby wedging the safety cable between the cradle and the safety cable engaging portions.

Abstract: By grasping a steel cable with a low cost portable self-tightening clamp that increases its holding force as the tensile pull force increases, one man can tighten steel cables of various lengths having bitter ends by using temporarily a single portable ratchet jack assembly to exert about 20 tons (20,000 KG) tightening force. Two similarly acting inexpensive clamps affixed to a barge deck hold the cable lines of various lengths without eyes in the end taut enough to bind barges together into one stiff unitary assembly, and permits the single ratchet (and portable clamp) assembly to be reused, thereby significantly reducing equipment inventory and cost.