| 摘要 |
PURPOSE: To reduce plate thickness of a power plate so as to reduce weight and production costs by arranging a taper part in a power plate and applying force to a power piston from the taper part in the power plate. CONSTITUTION: A taper part 6a is provided in a power plate 6, and a power piston 7 is engaged with the taper part 6a in the power plate 6. When the power piston 7 receives application force in the left direction from the taper part 6a in the power plate 6, the taper part 6a in the power plate 6 receives its reaction force in the right direction from the power piston 7. This reaction force works in the tensile direction of the power plate 6. Therefore, the power plate 6 is provided with great strength proof stress, and plate thickness can be reduced, so that weight and production costs of a negative pressure type booster device can be reduced. |
