Patent ID: 7477316
Filing Date: 2009-01-13
Classification: H04N

Abstract:
1. A pivot shaft mechanism comprising: a rotation support cylinder; an inner shaft concentrically supported in said rotation support cylinder so that said inner shaft and said rotation support cylinder are relatively rotatable about a rotational axis; an annular space formed about said rotational axis between an inner peripheral surface of said rotation support cylinder and an outer peripheral surface of said inner shaft; a pair of engaging recesses formed on said outer peripheral surface of said inner shaft at different circumferential positions thereon to be communicatively connected with said annular space; and a resilient ring member which includes an arc-shaped arm portion which is formed as a partial annular ring having an open portion, and a pair of bent end portions formed at opposite open ends of said arc-shaped arm portion, respectively, each of said pair of bent end portions being formed by bending an associated end portion of said resilient ring member radially inwards so that said pair of bent end portions are symmetrically shaped, wherein said resilient ring member is installed between said rotation support cylinder and said inner shaft with said arc-shaped arm portion being installed in said annular space in a resiliently deformed state and with said pair of bent end portions being installed in said pair of engaging recesses in a resiliently deformed state to apply a frictional resistance between said rotation support cylinder and said inner shaft.