Ratchet braking structure that can resume its actuating position without a torsion spring

摘要

A ratchet braking structure, that can resume its actuating position without a torsion spring, includes a ratchet wheel 10 and a pair of pawls 20 provided on opposite sides of the ratchet wheel 10. Each pawl 20 has a centre of rotation 21 and two opposing end portions 22, 23, wherein the two end portions are an engaging end 22 for engaging with and thereby locking the teeth 11 of the ratchet wheel 10 and a balancing end 23 for enabling pawl position restoration. The engaging end 22 of one pawl 20 is diagonally opposite that of the other. The balancing end 23 of each pawl extends from the side opposite the engaging end 22 and can be pushed outward by the teeth 11 of the ratchet wheel 10 so that, even without additional position restoration means, the engaging end 22 will stay where it can engage with the ratchet wheel 10.