Lockable overshot

Abstract

Lockable overshot () includes an elongated body (), lifting dogs () and a locking sleeve (). Ends () of the lifting dogs () are configured for latching a conventional spearhead point therebetween. The locking sleeve () is retained on the body () and is provided at one axial end with a circumferential wall () and two diametrically opposed gaps (). The locking sleeve () is rotatable on the body () between a locked state preventing ends () of the lifting dogs from pivoting away from each other to release a previously latched spearhead point, and an unlocked state where the locking sleeve () allows the lifting dogs () to move so that the ends () can be pivoted away from each other to release a previously latched spearhead point. In this regard, the locking sleeve () is provided at one axial end with a circumferential wall () provided with a pair of diametrically opposed gaps (). When the locking sleeve () is in the locked state, the wall () is disposed inside or between ends () of the lifting dogs (). This prevents the ends () of the lifting dogs from pivoting away from each other. When in the unlocked state, the gaps () register with the ends () of the lifting dogs () so that the ends () can be pivoted toward each other thereby pivoting the ends () away from each other to release a previously latched spearhead point.