| 摘要 |
PROBLEM TO BE SOLVED: To provide a drum brake having a shoe clearance automatic adjusting mechanism hardly affected by a change in an environmental temperature.SOLUTION: When a temperature sensitive deformation member 66 begins to deform by an environmental temperature, a second temperature sensitive deformation member 68 is deformed to a side for suppressing the deformation of the first temperature sensitive deformation member 66 by the environmental temperature, so that the deformation of the first temperature sensitive deformation member 66 is suppressed. When a transient temperature difference is generated however between the first temperature sensitive deformation member 66 and the second temperature sensitive deformation member 68 due to friction heat during braking, the first temperature sensitive deformation member 66 is deformed against the second temperature sensitive deformation member 68, thereby suppressing separation of a first strut member 56 from a brake shoe 20. As a result, a shoe clearance automatic adjusting mechanism 26 is hardly affected by the change in the environmental temperature, and overadjustment is suitably prevented by the temperature increase caused by the friction heat. |
