Patent ID: 8649122

Claim:
A rack-and-pinion mechanism comprising a first block including a rack and a second block including a pinion in which teeth are disposed to oppose the first block to engage with the rack, the first and second blocks relatively conducting linear movement in association with rotation of the pinion, wherein: in the second block, a pair of projections are formed to sandwich axially side surfaces of the pinion, the projections perpendicularly rising toward the first block and curving or bending in an intermediate position thereof; in the first block, a pair of grooves are formed on sides of the rack in a shape to engage with the pair of projections, the pair of grooves extending parallel to the rack, and a section sandwiched by the pair of grooves comprises an engage section including the rack in a center of a wide section at a tip end thereof; and by engaging the pair of projections with the grooves, the wide section at the tip end of the engage section is held between the pair of projections.