| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a hemi-spherical shoe 1 having an excellent slide characteristic and along service life. SOLUTION: A hemi-spherical shoe 1 is provided with a hemi-spherical convex surface 1A slidably coming contact with a hemi-spherical concave surface 2A of a piston 2. The hemi-spherical convex surface 1A is formed of a convex surface of a rotary body obtained when a circular arc having a radius R2 with the center C offset from an axial line L of the hemi-spherical shoe 1 in the orthogonal direction of the axis L, is rotated around the axis line L as a rotary center. An edge portion on a top side of the hemi-peripheral convex surface 1A forms a drawing portion 1G with a circular arc cross-section which keeps a space 7 between the drawing portion 1G and the hemi-peripheral concave portion 2A. A lubricating oil stored in a space portion 4 can be smoothly supplied through the space 7 to a sliding contact surface 1F.</p> |
