GB623246A - Opening device for grab-buckets - Google Patents

Abstract

623,246. Grab-buckets. SOC. FRANCAISE DE CONSTRUCTION DE BENNES AUTOMATIQUES. April 18, 1947, No. 10425. Convention date, April 1, 1943. [Class 78 (iv)] In a single-chain grab bucket the opening crown 2 which is suspended from the jib of a crane, is provided with three pivoted latches 19 for engaging a slider 12 on the bucket head 6, and the slider has a limited movement relatively to the head, which movement controls the pawls 8 on the head and allows them to turn into position to be supported by a disc 24 mounted on the actuating chain 3. A sleeve 22 mounted on the crown holds the latches 19 in the position shown in Fig. 3a when the bucket is not attached to the crown. When a full bucket is hoisted by the chain 3, its head 6 lifts the sleeve 22 whereupon the latches 19 fall into the position shown in Fig. 4a beneath the lip of the slider 12. The chain is now slackened until the disc 24 Fig. 6a, rests on the ledge 25 at the bottom of the slider 12. On raising the chain the disc 24, Fig. 7a, engages the pawls 8 and raises the slider until it abuts against'the crown 2. During this movement the sleeve 22 retracts the latches 19 and the bucket is free to descend. When the bucket rests on the load, the chain is slackened, the slider 12 drops and retracts the pawls 8 leaving the interior of the slider free for the passage of the disc 24 when hoisting is resumed. Longitudinal passages are provided between the parts to enable dirt &c. to pass away.