| 摘要 |
PURPOSE:To make a lock tooth of at least one lock member possible to be engaged with a lock hole at an optional position, by setting width of the lock tooth and that of the lock hole on the basis of a pitch period of the lock hole. CONSTITUTION:Plural lock holes 3 are installed at the side of a lower rail 1 along an axial direction at a pitch P od regular intervals, and n (=1,2...) pieces of movable lock members 7a and 7b are attached, with screws, to the side of an upper rail 4 tiltably around each axis and along an axial direction at a pitch mP (m=1,2...). And, there are provided with m pieces of a lock tooth 10a being formed in these movable lock members 7a and 7b so as to be engageable or detachable to or from these lock holes 3 as well as so as to have a phase difference with each other to the pitch period, and when this width is set to X and width of each lock hole 3 to (a), respectively, the pitch P is set so as to become P>a>X+P>n. |
