CLAMSHELL Russian patent published in 2007 - IPC B66C3/04 

FIELD: mechanical engineering; materials handling facilities.

SUBSTANCE: proposed clamshell contains vertical hydraulic cylinder 2 hinge-mounted in upper part of housing 1 whose rod engages with scoops 7 through tie-rods 3, 4 and levers 6 hinge-mounted on axles 5. Scoops 7 are hinge-secured by horizontal axles 8 on free ends of bow members 9 rigidly fixed at edges of horizontal cross-member 10 rigidly connected with lower part of housing 1. Each scoop 7 has two rows of gripping teeth 11, 12. Each gripping tooth 11 found on scoop 7 in first row has inner profile, in form of curve in lower part along which stem moves. Curvature of said curve corresponds to section of involute of circle AC. Radius of evolute of involute of circle is equal to distance from center of hinge joint of scoop 7 on bow-shaped member 9 to vertical axis of symmetry of clamshell.

EFFECT: improved operating conditions of clamshell.

3 cl, 7 dwg