Cylinder band for buoyancy regular

A cylinder band for a buoyancy regulator comprising:

• a belt adapted to be wound around a peripheral surface of an air cylinder destined to be immobilized on a backplate of said buoyancy regulator and having longitudinally opposite ends;
• a buckle attached to one of said longitudinally opposite ends by means of a coupler provided separately of said belt and provided with insertion slits through which the other of said longitudinally opposite ends may be guided to adjust a length of said belt;
• said buckle comprising a pair of supporting walls extending in parallel to each other in a circumferential direction of said peripheral surface of said air cylinder destined to be immobilized on said backplate and a plurality of dividing walls extending between a pair of said supporting walls in parallel one to another in a longitudinal direction of said air cylinder, each of said insertion slits being defined between each pair of the adjacent dividing walls, a pair of said supporting walls respectively have first ends and second ends opposed to said first ends in said circumferential direction of said air cylinder wherein said first ends are attached to said coupler so that said first ends swing around a pivot extending in the longitudinal direction of said air cylinder and said second ends swing off from or toward said peripheral surface of said air cylinder as said first ends swing around said pivot;
• and
• each of respective end surfaces of said first ends defines a cam surface serving to enhance a tensity of said belt guided through said insertion slits and pressed against said peripheral surface of said air cylinder in said circumferential direction wherein said cam surface includes a pair of surface segments spaced from each other in said circumferential direction of said peripheral surface and convexly curved toward said peripheral surface so that these convexly curved surface segments are adapted to come in contact with the peripheral surface at once in the course of enhancing a tensity of said belt and a concavely curved surface segment extending between these two convexly curved surface segments and having a curvature radius which is same as or less than a radius of the peripheral surface.