Swash plate type hydraulic unit

A swash plate type hydraulic unit comprising:

• a cylinder block (4) having a multitude of cylinder bores (25, 39) arranged annularly in parallel with a cylinder block axis (X) on a pitch circle (C1) which surrounds said axis (X),
• a multitude of plungers (27, 41) slidably fitted respectively in the cylinder bores (25, 39), and
• a plunger swash plate (9a, 19a) for rotating relatively with respect to the cylinder block (25, 39), thereby causing the plungers (27, 41) to reciprocate,
• characterized in that:
• said cylinder block (4) is formed by combining a plurality of block plates (41 to 45) with one another, said block plates being divided at split planes extending orthogonal to the cylinder block axis (X);
• said cylinder bores (25, 39) are comprised of inlet holes (25i, 39i) for supporting corresponding said plungers (27, 41) slidably and inner holes (25o, 39o) of a diameter larger than that of said inlet holes (25i, 39i), said inlet holes (25i, 39i) being formed in an inlet-side one of said block plates (41, 42;
• 44, 45) positioned on a side which faces the plunger swash plate (9a, 19a), said inner holes (25o, 39o) being formed in remaining inner-side ones of said block plates (43 to 45;
• 41 to 43) to each define an oil chamber between said inner hole and the outer peripheral surface and end surface of the corresponding plunger (27, 41);
• said cylinder block (4) has positioning means (58) for coaxially arranging the cylinder bores (25, 39) in the block plates (41 to 45);
• said cylinder block (4) is provided with a plurality of valve holes (26, 40) having distributing valves (28, 42) mounted therein;
• and
• ports (25i, 39i) of the respective cylinder bores (4) are formed in groove shapes in the split plane of a part (43) of the block plates so as to be controlled selectively by said distributing valves (28, 42).