| 摘要 |
<p>PURPOSE:To suppress the influence of frictional heat, generated when a brake is applied, to brake oil, by providing a heat transmission area reduced part, which suppresses the conduction of heat from the point end side to the rear end side, in the point end part of a caliper piston. CONSTITUTION:A recessed groove 17b is provided in the point end part of a caliper piston 17. The sectional area of a peripheral wall 17a is decreased in a place where the recessed groove 17b is provided, and the transmission of heat per unit time in said point end part is reduced as compared with the transmission in the other peripheral wall part. Accordingly, the transmission of heat from the point end of the caliper piston 17 to its rear end side can be effectively suppressed. Further the radiation area of heat in the point end part of the caliper piston 17 is increased by roviding the recessed groove 17b, causing the main unit part of the caliper piston to suppress a rise of its temperature as small as possible, thus the influence of heat to brake oil is decreased to a slight level.</p> |
