F15B21/0423

Hydraulic system of industrial vehicle

A hydraulic system of an industrial vehicle includes an oil tank in which hydraulic oil is retained; a hydraulic pump that draws in the hydraulic oil from the tank and supply the oil to a loading actuator and a brake unit; a brake valve that controls the hydraulic oil to be supplied to the brake unit according to an operation of a brake operation tool; a hydraulic oil cooler that cools the hydraulic oil; a cooling passage that allows the hydraulic oil to flow toward the cooler and further allows the oil cooled in the cooler to flow toward the brake unit; and a switching valve that switches between a first oil passage that cuts off a supply of the hydraulic oil from the hydraulic pump to the cooling passage and a second oil passage that allows the supply of the hydraulic oil from the hydraulic pump to the cooling passage.

Hydraulic system of industrial vehicle

A hydraulic system of an industrial vehicle includes an oil tank in which hydraulic oil is retained; a hydraulic pump that draws in the hydraulic oil from the tank and supply the oil to a loading actuator and a brake unit; a brake valve that controls the hydraulic oil to be supplied to the brake unit according to an operation of a brake operation tool; a hydraulic oil cooler that cools the hydraulic oil; a cooling passage that allows the hydraulic oil to flow toward the cooler and further allows the oil cooled in the cooler to flow toward the brake unit; and a switching valve that switches between a first oil passage that cuts off a supply of the hydraulic oil from the hydraulic pump to the cooling passage and a second oil passage that allows the supply of the hydraulic oil from the hydraulic pump to the cooling passage.

A HYDRAULIC ENERGY HANDLING SYSTEM, A HYDRAULIC PARALLEL HYBRID DRIVELINE AND A WORKING MACHINE
20210340998 · 2021-11-04 ·

A hydraulic energy handling system for a working machine includes a high-pressure side; a low-pressure side; a hydraulic machine for mechanically driving, and being mechanically driven by, a mechanical driveline of the working machine; at least one high-pressure hydraulic energy storage connected to the high-pressure side; a hydraulic motor; a hydraulic pump arranged to supply hydraulic fluid to an inlet side of the hydraulic motor; and a return line for conducting hydraulic fluid to a hydraulic tank. The system further includes a pressure relief valve between the high-pressure side and the return line and arranged to discharge excess hydraulic energy from the high-pressure side to the return line to provide a braking force on the mechanical driveline; and a priority valve arrangement connected to an outlet side of the hydraulic motor to direct a prioritized flow of hydraulic fluid to the low-pressure side.

Working machine

A working machine includes a prime mover, a hydraulic pump driven by power of the prime mover, a cooler including a cooling fan rotated by either the power of the prime mover or hydraulic fluid delivered from the hydraulic pump, and a controller configured or programmed to perform a reduction control for reducing a target fan rotation speed that is a target rotation speed of the cooling fan in response to reduction of an actual prime mover rotation speed that is an actual rotation speed of the prime mover, and to perform, after the reduction control, a restoration control for restoring the target fan rotation speed. The controller is configured or programmed to make a difference between a reduction rate of the target fan rotation speed in the reduction control and an increase rate of the target fan rotation speed in the restoration control.

Working machine

A working machine includes a prime mover, a hydraulic pump driven by power of the prime mover, a cooler including a cooling fan rotated by either the power of the prime mover or hydraulic fluid delivered from the hydraulic pump, and a controller configured or programmed to perform a reduction control for reducing a target fan rotation speed that is a target rotation speed of the cooling fan in response to reduction of an actual prime mover rotation speed that is an actual rotation speed of the prime mover, and to perform, after the reduction control, a restoration control for restoring the target fan rotation speed. The controller is configured or programmed to make a difference between a reduction rate of the target fan rotation speed in the reduction control and an increase rate of the target fan rotation speed in the restoration control.

Motor cooling via hydraulic fluid
11773882 · 2023-10-03 · ·

The hydraulic system according to the invention comprises a hydraulic circuit with a low-pressure region and a high-pressure region; a volume- and/or speed-variable hydraulic machine, which is driven by a first electric motor and has an inlet and an outlet and provides a volume flow of a hydraulic fluid in the high-pressure region of the hydraulic circuit. The hydraulic system according to the invention further comprises at least one movable shaft, which is arranged in the high-pressure region of the hydraulic circuit; at least one valve, which separates the high-pressure region from the low-pressure region; and at least one hydraulic fluid container, which is hydraulically connected to the low-pressure region of the hydraulic circuit. The hydraulic system according to the invention also has a discharge line, which discharges hydraulic fluid from the leakage of the hydraulic machine, and a cooling line for transporting the hydraulic fluid in order to cool the electric motor, the discharge line and the cooling line being fluidically connected to at least one of the hydraulic fluid containers.

HYDRAULIC UNIT AND ASSEMBLY
20230287906 · 2023-09-14 · ·

A hydraulic unit includes a reversing pump which has two pump connections which act as a suction connection and pressure connection depending on rotation direction. The hydraulic unit has at least one suction intake for intake of hydraulic fluid. Starting from the suction intake, a suction line portion extends to each of the pump connections, and a non-return valve blocking in the direction towards the suction intake is arranged in each suction line portion. Starting from a first pump connection, a first pressure line extends to a lubricant connection of the hydraulic unit, wherein a non-return valve blocking in the direction towards the pump connection is arranged in the first pressure line. Starting from a second pump connection, a second pressure line leads to an actuator connection (of the hydraulic unit, wherein the second pressure line is free of valves. Furthermore, an assembly comprising a hydraulic unit is indicated.

HYDRAULIC UNIT AND ASSEMBLY
20230287906 · 2023-09-14 · ·

A hydraulic unit includes a reversing pump which has two pump connections which act as a suction connection and pressure connection depending on rotation direction. The hydraulic unit has at least one suction intake for intake of hydraulic fluid. Starting from the suction intake, a suction line portion extends to each of the pump connections, and a non-return valve blocking in the direction towards the suction intake is arranged in each suction line portion. Starting from a first pump connection, a first pressure line extends to a lubricant connection of the hydraulic unit, wherein a non-return valve blocking in the direction towards the pump connection is arranged in the first pressure line. Starting from a second pump connection, a second pressure line leads to an actuator connection (of the hydraulic unit, wherein the second pressure line is free of valves. Furthermore, an assembly comprising a hydraulic unit is indicated.

Fluid circuit for air cylinder
11619245 · 2023-04-04 · ·

In a fluid circuit for an air cylinder connected to a switching valve provided with exhaust ports, a head-side pressure chamber is connected to the switching valve by a first pipe, and a rod-side pressure chamber is connected to the switching valve by a second pipe. A first restrictor is disposed at a connection point between the first pipe and the switching valve or in the vicinity of a first output port of the switching valve, and a second restrictor is disposed at a connection point between the second pipe and the switching valve or in the vicinity of a second output port of the switching valve.

WORKING MACHINE
20230349402 · 2023-11-02 · ·

A working machine includes a prime mover, a hydraulic pump driven by power of the prime mover, a cooler including a cooling fan rotated by either the power of the prime mover or hydraulic fluid delivered from the hydraulic pump, and a controller configured or programmed to perform a reduction control for reducing a target fan rotation speed that is a target rotation speed of the cooling fan in response to reduction of an actual prime mover rotation speed that is an actual rotation speed of the prime mover, and to perform, after the reduction control, a restoration control for restoring the target fan rotation speed. The controller is configured or programmed to make a difference between a reduction rate of the target fan rotation speed in the reduction control and an increase rate of the target fan rotation speed in the restoration control.