The machine comprises distribution ducts connected to respective ones of first, second, and third enclosures (40, 42, 44), and a cylinder-capacity selector (21) suitable for being caused to take up a large cylinder capacity configuration in which the second enclosure (42) is connected to one of the main ducts (2), while the first and third enclosures (40, 44) are connected to the other main duct (1), and a small cylinder capacity configuration in which the second and third enclosures (42, 44) are connected to said one of the main ducts (2), while the first enclosure is connected to the other main duct (1). The machine further comprises a safety valve (150) having at least a first port (56) connected to said one of the main ducts (2), and a second port (58) connected to the third enclosure (44). Said safety valve is suitable, when the cylinder-capacity selector (21) is caused to go into the large cylinder capacity, for being caused to go into a first configuration that isolates the first and second ports (56, 58) from each other, and, when the cylinder-capacity selector is caused to go into its small cylinder capacity, for being caused to go into a second configuration that interconnects the first and second ports (56, 58).

The machine comprises distribution ducts connected to respective ones of first, second, and third enclosures (40, 42, 44), and a cylinder-capacity selector (21) suitable for being caused to take up a large cylinder capacity configuration in which the second enclosure (42) is connected to one of the main ducts (2), while the first and third enclosures (40, 44) are connected to the other main duct (1), and a small cylinder capacity configuration in which the second and third enclosures (42, 44) are connected to said one of the main ducts (2), while the first enclosure is connected to the other main duct (1). The machine further comprises a safety valve (150) having at least a first port (56) connected to said one of the main ducts (2), and a second port (58) connected to the third enclosure (44). Said safety valve is suitable, when the cylinder-capacity selector (21) is caused to go into the large cylinder capacity, for being caused to go into a first configuration that isolates the first and second ports (56, 58) from each other, and, when the cylinder-capacity selector is caused to go into its small cylinder capacity, for being caused to go into a second configuration that interconnects the first and second ports (56, 58).

A radial piston device includes a housing, a pintle attached to the housing and having a pintle shaft, a rotor rotatably mounted on the pintle shaft and having cylinders, pistons displaceably received in the cylinders, and a drive shaft coupled to the rotor and rotatably supported within the housing. The radial piston device includes mechanisms for reducing a pressure loss of hydraulic fluid flowing into the pintle shaft.

A radial piston device includes a housing, a pintle attached to the housing and having a pintle shaft, a rotor rotatably mounted on the pintle shaft and having cylinders, pistons displaceably received in the cylinders, and a drive shaft coupled to the rotor and rotatably supported within the housing. The radial piston device includes mechanisms for reducing a pressure loss of hydraulic fluid flowing into the pintle shaft.

When a condition for reducing a noise caused in the high-pressure pump is satisfied, a reduction control unit implements a noise reduction control to supply a smaller power to reduce a moving speed of a movable portion in a close acting direction to put a valve body into a closed state for a predetermined time after an energization start timing of a solenoid in a plunger rising period. A closing control unit causes a closing current, which is a constant current for surely putting the valve body into the closed state, to flow the closing current in the solenoid when the noise reduction control is completed in the plunger rising period. The predetermined time is shorter than an energization period in which a current flows in the solenoid.

When a condition for reducing a noise caused in the high-pressure pump is satisfied, a reduction control unit implements a noise reduction control to supply a smaller power to reduce a moving speed of a movable portion in a close acting direction to put a valve body into a closed state for a predetermined time after an energization start timing of a solenoid in a plunger rising period. A closing control unit causes a closing current, which is a constant current for surely putting the valve body into the closed state, to flow the closing current in the solenoid when the noise reduction control is completed in the plunger rising period. The predetermined time is shorter than an energization period in which a current flows in the solenoid.

A plunger pump fluid end assembly design in which the suction valve and seat is aligned with the plunger and the fluid end housing is constructed with multiple modules. Modules are held in a rigid assembly by staybolts that connect to the power end of the plunger pump. Said staybolts pass though bores in the central fluid module and the suction seat module and bound by a conventional threaded nut. Packing box modules are bound to the central fluid module by bolts that also pass through separate bores in the same central module. A suction valve spring retainer/plunger spacer within the plunger bore of the assembly shields the intersection of the plunger bore and the discharge bore from destructive erosion damage.

A plunger pump fluid end assembly design in which the suction valve and seat is aligned with the plunger and the fluid end housing is constructed with multiple modules. Modules are held in a rigid assembly by staybolts that connect to the power end of the plunger pump. Said staybolts pass though bores in the central fluid module and the suction seat module and bound by a conventional threaded nut. Packing box modules are bound to the central fluid module by bolts that also pass through separate bores in the same central module. A suction valve spring retainer/plunger spacer within the plunger bore of the assembly shields the intersection of the plunger bore and the discharge bore from destructive erosion damage.

An automotive hydraulic actuating system for actuating a movable vehicle part, like a roof part or a wheel suspension. The actuating system comprises a pump unit. The pump unit comprises a piston pump which has a pump rotor and an electric motor which has a motor rotor. The pump rotor and motor rotor are incorporated into a single common rotor. The rotor is a one piece item. The rotor is positioned inside a pump chamber around a pump stator of the piston pump. The pump stator provides a full support to the common rotor. Advantageously, without a separate motor stator, the pump unit has a more compact configuration. Additionally, the pump unit has an improved dynamic performance which contributes to a silent and reliable operation at a high rotational speed.

An automotive hydraulic actuating system for actuating a movable vehicle part, like a roof part or a wheel suspension. The actuating system comprises a pump unit. The pump unit comprises a piston pump which has a pump rotor and an electric motor which has a motor rotor. The pump rotor and motor rotor are incorporated into a single common rotor. The rotor is a one piece item. The rotor is positioned inside a pump chamber around a pump stator of the piston pump. The pump stator provides a full support to the common rotor. Advantageously, without a separate motor stator, the pump unit has a more compact configuration. Additionally, the pump unit has an improved dynamic performance which contributes to a silent and reliable operation at a high rotational speed.