| 摘要 |
PURPOSE:To provide approximately ideal brake characteristics in an air brake valve generating secondary pressure in proportion to the pedalling amount of a brake pedal by giving a non-linear constant to a spring for balancing a piston. CONSTITUTION:When a brake pedal connected to a bracket 15 is depressed into a cap 16, a plunger 19 is moved downward and a piston 20 is pushed down through a balancing spring 30. Thus, an exhaust valve 21 abuts against a feed valve cylinder 22 to be closed, and a feed valve 23 moves down to be opened. Hence, compressed air from an air tank flows to a secondary port 28 through a primary port 27 and is supplied to a brake unit. Then, since a balancing spring 30 having a non-linear spring constant is used in which for example the diameter of wire rod is reduced as it goes upward, the change in secondary pressure to pedal stroke can be made a desired non-linear one. |
