| 摘要 |
<p>A portable winch-hoist comprises a main supporting frame, with an anchor hook, and carrying a ratchet-driven cable drum and an actuating frame, or lever, which may in practice be generally U-shaped and may span the main frame and which is pivoted for swinging movements about the axis of the cable drum. Pawls carried by the main frame and by the lever are selectively cooperable with the drum ratchet to rotate, to hold, and to release, the drum, so as to reel, and to control the unreeling of, cable carried by the drum, in response to pivotal swinging of the lever. The cable is releasably retained on the drum, being wrapped thereon and passing through portions of the drum at two axially-spaced points, whereby sufficient turns of cable are retained on the drum to assure a capstan or snubbing effect, under all normal operating conditions, with an end portion of the cable arranged for set-screw securement to the drum, whereby cable replacement is simplified. The lever includes provision for attachment thereto of an operating handle, in any one of several positions, for facility and ease of operation, and to assure ample leverage under all conditions; and the handle has a safety link, bendable when the force applied to the handle exceeds a predetermined amount, and the handle also has within it a space adapted to house spare links. When the hoist is used with the cable looped or passing around a pulley of a pulley-block to form two lines, the cable end remote from the drum is releasably secured, by the cable-end-hook, to the main frame in a position which makes it possible to use a lighter construction for the main frame, for a given load capacity, and substantially reduces the minimum distance achievable between the anchor hook and the pulley-block-hook.</p> |
