Maeda MK0003, Service Manual, Page: 108 / 348

2-80
[5] Actuation of reducing valve
1. When secondary pressure is below a set
value
Since reducing valve spool (1) is pushed by reducing
valve spring (2), the hydraulic oil of primary pressure
flows through the path (a) of reducing valve spool (1)
toward the secondary pressure side.
1. Reducing valve spool
2. Reducing valve spring
2. When the primary pressure exceeds the set
value of secondary pressure
Reducing valve spool (1) moves until reducing valve
spring (2) comes to be balanced and squeezes the
path (a) of reducing valve spool (1) to maintain the
secondary pressure at the set value.
3. When secondary pressure is above a set
value
Reducing valve spool (1) moves until the secondary
pressure comes to be balanced with reducing valve
spring (2), closes path (a), and concurrently opens
path (b) to allow the path to communicate with the
tank to reduce the secondary pressure to the set
value.
Tank
Primary
pressure
Secondary
pressure
Primary
pressure
Primary
pressure
Secondary
pressure
Secondary
pressure