| 摘要 |
PURPOSE:To permit correct positioning of a shoe by installing an engagement part having a concaved or convex part onto a fixed member and installing an engagement part having a convex or concaved part for the engagement with the engagement member onto the intermediate part of the shoe. CONSTITUTION:An engagement member 20 having a semispherical convex part 18 is fixed in the vicinity of the base edge of the second fixed part 3 of a fixed member 1, and a concaved engagement part 22 for fitting the covex part 18 of the engagement member 20 is formed at the nearly intermediate part of a shoe 5 corresponding to the engagement member 20. Therefore, when the shoe 5 is returned back reversely from the direction of expansion, the shoe is-with-and fitted convex part 18 of the engagement member 20 and the concaved engagement part 22, the shoe 5 is always returened to a fixed position, and correct positioning of the shoe 5 is permitted. Thus, the constant clutch brake effect can be maintained, and drag phenonmenon due to one-side contact, etc. is eliminated. |
