A drive system for an industrial handling vehicle comprises an electric motor, a first pump, for example, a plunger pump, and a second pump, for example, a gear pump. The first pump is configured to provide hydraulic power for a travelling device of the industrial handling vehicle. The first pump and the travelling device are in a first hydraulic circuit. The second pump is configured to provide hydraulic power for a brake device and/or a steering device and/or a handling device of the industrial handling vehicle. The second pump, the brake device, the steering device, and the handling device are in a second hydraulic circuit isolated from the first hydraulic circuit. The electric motor is operatively coupled to both the first pump and the second pump, to drive them to operate.

A drive system for an industrial handling vehicle comprises an electric motor, a first pump, for example, a plunger pump, and a second pump, for example, a gear pump. The first pump is configured to provide hydraulic power for a travelling device of the industrial handling vehicle. The first pump and the travelling device are in a first hydraulic circuit. The second pump is configured to provide hydraulic power for a brake device and/or a steering device and/or a handling device of the industrial handling vehicle. The second pump, the brake device, the steering device, and the handling device are in a second hydraulic circuit isolated from the first hydraulic circuit. The electric motor is operatively coupled to both the first pump and the second pump, to drive them to operate.

An electric motor driven pump assembly configuration that includes an electric motor, a hydraulic pump driven by the electric motor is provided. The hydraulic pump is driven by the electric motor to convert electrical power into hydraulic power. A multi-inlet hydraulic pump enhances cooling flow through a pump case of the assembly and also enhances cooling flow for cooling the electric motor and corresponding drive/control components.

A submersible pumping system has an electric motor, a rotary hydraulic pump driven by the electric motor, and a linear hydraulic pump that is configured to move a production fluid. The rotary hydraulic pump produces a pressurized working fluid that drives the linear hydraulic pump. In another aspect, a method is disclosed for controlling the temperature of an electric motor within a submersible pumping system disposed in a wellbore. The method includes the steps of circulating motor lubricant through a hydraulically driven production pump to reduce the temperature of the motor lubricant.

A fluid supply system includes: a centrifugal pump; a starting pump that is connected to the centrifugal pump in series, is provided downstream of the centrifugal pump, and has a discharge flow rate less than that of the centrifugal pump; a measuring valve that is provided downstream of the centrifugal pump and the starting pump, measures an amount of fluid discharged from the centrifugal pump or the starting pump, and discharges the fluid to a downstream each time the fluid reaches a predetermined flow amount; a differential pressure valve that is provided downstream of the centrifugal pump and the starting pump, and is driven based on a differential pressure between an upstream pressure and a downstream pressure of the measuring valve; and a flow rate control valve that is provided downstream of the centrifugal pump and upstream of the differential pressure valve and has a valve opening speed that is set slower than that of the differential pressure valve.

A recirculation gas flow control and distribution assembly that includes an electric motor and a pump coupled to the electric motor. The pump includes a pump housing with a pump inlet and a pump outlet. The pump inlet is fluidly connected to a recirculated gas. At least one nozzle is directly connected to the pump housing. A passage is formed in the pump housing and nozzle linking the pump inlet to the nozzle. An injector is coupled to the nozzle, the injector is fluidly connected to a fuel. A valve is disposed in the passage, the valve is movable between open and closed positions. The recirculated gas is selectively passed to the pump outlet and fuel is selectively feed into the nozzle.

In a hydraulic control device, when it is detected that a pressure of first oil (output pressure) detected by an output pressure sensor pulsates, a transmission control unit as a TCU stops driving of a second pump or decreases a rotation number of the second pump as a first operation. Alternatively, when it is detected that the output pressure pulsates, the TCU increases the rotation number of the second pump to a rotation number (for example, maximum rotation number) that is higher than a target rotation number as a second operation.

A fuel pumping unit has a low pressure centrifugal pump and a high pressure centrifugal pump. In use, the low pressure pump supplies fuel at a boosted pressure to the high pressure pump for onward supply to a fuel metering unit. The pumping unit further has a drive input which drives the low and high pressure pumps. A gear arrangement is operatively located between the drive input and the low and high pressure pumps such that the low and high pressure pumps are driven at different speeds by the drive input.

A fuel pumping unit has a low pressure centrifugal pump and a high pressure centrifugal pump. In use, the low pressure pump supplies fuel at a boosted pressure to the high pressure pump for onward supply to a fuel metering unit. The pumping unit further has a drive input which drives the low and high pressure pumps. A gear arrangement is operatively located between the drive input and the low and high pressure pumps such that the low and high pressure pumps are driven at different speeds by the drive input.

A hydraulic pump assembly having a main pump, a charge pump and an auxiliary pump driven by a single shaft is provided. A pair of hydraulic porting members cooperates to feed and distribute hydraulic fluid between the three pump units, and a single inlet may be used to provide hydraulic fluid to the charge pump and the auxiliary pump.