| 摘要 |
PROBLEM TO BE SOLVED: To quickly increase output of a brake booster in response to quick pressing-on operation of a brake pedal. SOLUTION: During normal brake operation, brake reaction force from a reaction disk 12 is transmitted to a valve plunger 15 through an outer plunger 17 and an inner plunger 18. During emergency brake operation, when the valve plunger 15 advances the prescribed stroke to a valve body 3, a cylindrical member 24 retreats to the valve body 3. Then, in the servo balance state, the valve plunger 15 retreats by a distance equivalent to the retreat of the cylindrical member 24, and the outer plunger 17 gets into contact with a holder 13. Since the brake reaction force from the reaction disk is transmitted to the valve plunger 15 through only the inner plunger 18, the boosting ratio can be made larger than that in normal brake operation, and the jumping amount can be enlarged. |
