A hydraulic spool valve is provided in which two inlet bores and an outlet bore
lead into a housing. A spool-valve piston which is under the influence of compression
springs on both sides can be displaced longitudinally in the housing. When a difference
in pressure of the hydraulic fluid in the inlet bores occurs, the inlet bore which
conducts the lower pressure in each case is connected to the outlet bore. The two
compression springs are pre-stressed and have an additional expansion path. During
the displacement of the spool-valve piston from a neutral central position into
an extended intermediate position, the two compression springs therefore remain
in operative connection with the spool-valve piston, in which case the spring forces
counterbalance each other until the intermediate position is reached.