PURPOSE: To suppress variation of a thrust synthesized load while the change of the oil pressure in a cylinder hole corresponding to each plunger is made gradual.
CONSTITUTION: A communication port 13a is formed between an influx port 15 and an efflux port 14. These ports 15, 14 are arranged so that the oil pressure in the communication port 13a meets the conditions θ1=θ2=360°/Zxk and θ3=180°, where θ1 is the rotational angle of cylinder block corresponding to the division in which boosting is made from the pressure in the low pressure side port to the pressure in the high pressure side port, θ2 is the rotational angle of cylinder block 4 corresponding to the division in which decompression is made from the pressure in the high pressure side port to the pressure in the low pressure side port, and θ3 is the rotational angle from commencement of boosting to starting decompression; and further Z is the number of plungers which should be odd, while k is integer 1, 2, 3....
KANAMARU YOSHIHIRO
TANE TOSHIAKI
OGAWA HIROHISA
