2-1
GROUP 1 HYDRAULIC PUMP
1. GENERAL
This is a variable displacement double-piston pump for discharge with equal displacements from one
cylinder block. This pump is so compact as to appear a single pump though this is actually a double
pump.
Because this pump has one swash plate, the tilting angle is the same for two pumps. Tilting of the
pump changes in response to the total pressure of P1 + P2. Namely, the output is controlled to the
constant value so that the relationship between the discharge pressure and flow rate Q becomes
constant, (P1 + P2) * Q =Constant.
The third pump and pilot pump can be connected to the same shaft via a coupling.
R1
A1 A2 A4 A3
S1
S1
A4
A3
A1
A2
A2
A1
A3
R1
A
VIEW "A"
DIRECTION OF
ROTATION
Description of the ports
Port
Name
Bore
S
A1, A2, A3
A4
R1
Suction port
Discharge port
Pilot port
Air bleeder port
SAE 1 1/2 (Standard)
PF 1/2
G 3/8
With bleeder valve(M10
Ý
1.0)
R35Z72MP01
SECTION 2 STRUCTURE AND FUNCTION