B42.60-0222-12
Framework
1 Supply connection
2 Output connection with braking pressure
3 Discharge (exhaust)
4 Spring
5 Hole
6 Piston
7 Air output
8 Double cone valve
9 Air passage
10 Lever
11 Upper stop
12 Lower stop
a Supply pressure
b Braking pressure
B42.60-0223-01
Operation:
I - Gear position
With the lever (10) at the released brake position the air passage (9) will be closed and the output (7) open. With that, the circuit (2) is communicating with the atmosphere through the passage (7), hole (5) and exhaust (3).
B42.60-0224-01
II - Partial brake actuation:
When the lever (10) is actuated, the upper stop (11) with its tilted surface, will displace the lower stop (12) downwards. The lower stop will transfer the force received to the spring (4) which, in turn, will displace the piston (6) downwards closing the air output (7) and opening the passage (9).
This way the compressed air will flow from the connection (1) to the connection circuit (2), partially applying the semi-trailer brake according to the lever position (10).
As the pressure in the chamber (A) increases, the air actuating on the lower part of the piston (6), pushes it upwards, against the spring action (4), until there is a force balance between the two faces of the piston. In this position, the air flow (9) and the output (7) are closed by the double cone valve (8).
B42.60-0225-01
III - Total brake actuation:
Gradually actuating the lever (10), the upper stop (11) rotates pushing the lower stop (12) downwards, compressing the spring (4) and the piston (6) is displaced, closing the air flow (7) and opening the passage (9) where the connection air pressure (1) comes to the connection (2), compressing the line after the valve (8).
B42.60-0226-01
IV - Exhaust position:
When the lever (10) is moved to the resting position, the spring tension (4) reduces and the chamber pressure (A) overtakes the spring tension, opening the exhaust (7). This way, the flow through the connection(2) to the exhaust connection (3) is free, releasing line air.