A control valve for a pump for delivering a fluid. The control valve includes: a valve housing which delineates a piston chamber; a piston which can be moved within the piston chamber; and a fluid channel which ports into the piston chamber via a port opening, wherein the port opening defines a port control edge. The valve housing includes a recess which extends into the fluid channel, wherein the recess defines a recess control edge which is axially offset with respect to the port control edge, and/or the piston includes a piston recess which defines a piston recess control edge.

There is disclosed a pump apparatus which can more accurately determine the occurrence of an abnormal vibration. The pump apparatus includes: a pump; an electric motor for driving the pump; an inverter as a speed changing means for the electric motor; a vibration detector for detecting at least one of a vibration of the pump, a vibration of the electric motor and a vibration of the inverter; and a controller for controlling the pump. The controller includes a storage unit for storing a measured vibration value measured by the vibration detector. The storage unit has a storage table which, when the rotational speed of the pump is increased stepwise to a predetermined rotational speed, stores the measured vibration value measured at each step.

A hydraulic brake motor device, including a motor positioning, installation and driving portion, a motor body meshing pair portion, and a motor brake device portion. A shuttle valve is integrated inside the hydraulic brake motor device and configured to relieve pressure inside the motor brake device portion. The shuttle valve includes two separate functional parts of check valves.

One embodiment of a pump may include an idler gear having a plurality of idler gear teeth extending radially outward, wherein at least one of the idler gear teeth may be formed with an idler gear cavity therein. The pump may include a drive gear having a plurality of drive gear teeth extending radially outward that may be intermeshed with the idler gear teeth during use. The drive gear may be formed with a recess at on axial end thereof, and the axial position of the recess may correspond to the axial position of the idler gear cavity. In one embodiment of a pump, each idler gear tooth may be formed with an identical idler gear cavity at the same relative position on each idler gear tooth.

One embodiment of a pump may include an idler gear having a plurality of idler gear teeth extending radially outward, wherein at least one of the idler gear teeth may be formed with an idler gear cavity therein. The pump may include a drive gear having a plurality of drive gear teeth extending radially outward that may be intermeshed with the idler gear teeth during use. The drive gear may be formed with a recess at on axial end thereof, and the axial position of the recess may correspond to the axial position of the idler gear cavity. In one embodiment of a pump, each idler gear tooth may be formed with an identical idler gear cavity at the same relative position on each idler gear tooth.

A pumping method in a pumping system comprises: a main vacuum pump with a gas inlet port connected to a vacuum chamber and a gas outlet port leading into a conduit before coming out into the gas outlet of the pumping system, a non-return valve positioned in the conduit between the gas outlet port and the gas outlet, and an auxiliary vacuum pump connected in parallel to the non-return valve. The main vacuum pump is activated in order to pump the gases contained in the vacuum chamber through the gas outlet port, simultaneously the auxiliary vacuum pump is activated and continues to operate all the while that the main vacuum pump pumps the gases contained in the vacuum chamber and/or all the while that the main vacuum pump maintains a defined pressure in the vacuum chamber. Also included is a pumping system.

A vehicle driving apparatus including: a fluid pump; a rotary member; a bearing supporting the rotary member; a pump cover covering the fluid pump; a relief valve; and a casing storing the fluid pump, the rotary member, the bearing, the pump cover and the relief valve. The casing includes a casing body and a casing cover. The casing cover defines a fluid passage that is in communication with an outlet port of the fluid pump, and includes cylindrical-shaped first and second boss portions. The first boss portion includes a supporting portion supporting the rotary member through the bearing which is fitted in a space radially inside the first boss portion. The second boss portion defines a valve room that is in communication with the fluid passage, with the relief valve being stored in the valve room.

A fuel system for a turbomachine includes a fuel tank and a first fuel line in fluid communication with the fuel tank and one or more fuel injectors. The first fuel line includes a main fuel pump disposed on the first fuel line, and an electric metering system disposed on the first fuel line downstream of the main fuel pump configured for starting the turbomachine and metering fuel to the fuel injectors.

A fuel system for a turbomachine includes a fuel tank and a first fuel line in fluid communication with the fuel tank and one or more fuel injectors. The first fuel line includes a main fuel pump disposed on the first fuel line, and an electric metering system disposed on the first fuel line downstream of the main fuel pump configured for starting the turbomachine and metering fuel to the fuel injectors.

The invention suppresses hysteresis. A relief valve switching between whether to discharge oil through movement of a valve body includes: a first spacing part, in which the valve body moves; a second space part, connected with the first space part and having a diameter smaller than a diameter of the first space part; an elastic body, connected with the valve body; a seal part, disposed in a circumferential direction of the valve body; and a third space part, formed in the first space part.