A filter (5) for a return line (L1, L2) for hydraulic oil to a hydraulic tank (2), which filter (5) has a filter element (11). The filter (5) is arranged to filter the hydraulic oil through the filter element (11) when the hydraulic oil is below a first oil level (H1) in the filter (5), and the filter (5) has an arrangement (15) to cause the hydraulic oil to bypass the filter element (11) when the oil level (H) in the filter (5) exceeds the first oil level (H) without causing any significant back pressure.

An inspection device for hydraulic equipment includes a hydraulic circuit having a branch valve, an optical detection section, a pump configured to supply oil to the hydraulic circuit, and a controller. The optical detection section includes an inspection oil passage connected to the branch valve. The inspection oil passage includes a filter arranged to collect foreign matter. The controller operates the branch valve to supply oil to the inspection oil passage. The optical detection section includes first and second foreign matter detection sections arranged on upstream and downstream sides of the filter to detect foreign matter. A work vehicle includes the inspection device. An inspection system includes the inspection device. An inspection method includes supplying oil to an inspection oil passage by operating a branch valve of a hydraulic circuit, and detecting foreign matter on upstream and downstream sides of a filter arranged on the inspection oil passage.

A flow limiter component including a monocoque body having first, second, and third sections along a longitudinal axis. The first section includes a first end defining a first edge of the monocoque body and a bordering second end, and a first inner diameter defining a first chamber inside the first section. The second section includes a solid wall, with an orifice disposed therein, in fluid communication with the first chamber, the orifice defined by a second inner diameter. The third section includes a third end bordering the second section and a fourth end defining a second edge of the body, and a third inner diameter, the third inner diameter defining a second chamber in the third section. The second chamber is in fluid communication with the orifice. The first inner diameter is greater than the third inner diameter, and the third inner diameter is greater than the second inner diameter.

A flow limiter component including a monocoque body having first, second, and third sections along a longitudinal axis. The first section includes a first end defining a first edge of the monocoque body and a bordering second end, and a first inner diameter defining a first chamber inside the first section. The second section includes a solid wall, with an orifice disposed therein, in fluid communication with the first chamber, the orifice defined by a second inner diameter. The third section includes a third end bordering the second section and a fourth end defining a second edge of the body, and a third inner diameter, the third inner diameter defining a second chamber in the third section. The second chamber is in fluid communication with the orifice. The first inner diameter is greater than the third inner diameter, and the third inner diameter is greater than the second inner diameter.

An oil pressure control device controls a supply pressure of oil supplied to an oil pressure chamber of a friction element having a first engagement board and a second engagement board engaged with or disengaged from each other between a non-engagement state and a non-sliding engagement state via a sliding engagement state. The oil pressure control device includes: an electromagnetic valve that controls the supply pressure using a spool which reciprocates according to an energizing amount; and a control part that defines a first oscillatory wave part in which the energizing amount is controlled by making a first waveform with a first frequency to superimpose on a second waveform with a second frequency higher than the first frequency during a first period while the sliding engagement state and an instruction value of the supply pressure are kept constant.

A hydraulic system including a first cylinder conduit configured to couple to a cylinder, a second cylinder conduit configured to fluidly coupled to the cylinder, and a bypass conduit fluidly coupled both to the first cylinder conduit upstream of the cylinder and to the second cylinder conduit downstream of the cylinder. The bypass conduit is configured to enable intermittent fluid flow of a hydraulic fluid from the first cylinder conduit to the second cylinder conduit while bypassing at least a portion of the cylinder.

A hydraulic system including a first cylinder conduit configured to couple to a cylinder, a second cylinder conduit configured to fluidly coupled to the cylinder, and a bypass conduit fluidly coupled both to the first cylinder conduit upstream of the cylinder and to the second cylinder conduit downstream of the cylinder. The bypass conduit is configured to enable intermittent fluid flow of a hydraulic fluid from the first cylinder conduit to the second cylinder conduit while bypassing at least a portion of the cylinder.

A device and a method for cleaning a hydraulic control circuit such as the hydraulic circuit serving to control a hydraulic element, for example, a cylinder/damper assembly used for controlling the angle of an aircraft landing gear assembly and providing shock absorption on landing. The device comprises a cleaning circuit comprising a filter that is connected to the control circuit instead of the controlled element.

A vehicle transmission having a valve body disposed adjacently to and in parallel with a side cover covering a front or rear side or a side surface of a transmission case in a vehicle width direction in a vehicle-mounted state, the side cover connected to the transmission case, in which an electromagnetic valve is included on the side cover side of the valve body, when viewed in a direction horizontal and parallel to mating surfaces of the transmission case and the side cover, a strainer for removing a foreign material in a hydraulic oil is disposed between the side cover and the valve body to overlap with at least a portion of the electromagnetic valve, and the strainer has an inflow portion for allowing the hydraulic oil to flow in disposed vertically above an oil surface.

A compressed-air treatment system and operating method are disclosed. The compressed-air treatment system has a first valve unit configured to charge a control line for a compressor with pressure and a pressure regulator valve unit configured to release pressure from a feed line, A control port of the pressure regulator valve unit is connectable to a second valve unit. A regeneration line which has a check valve for regeneration and which is utilized for a regeneration of a dryer cartridge is connected directly to the control line. During a filling operation the compressed-air treatment system is configured to release leakage air of the regeneration check valve via the first valve unit to surroundings. The filling operation is an operating state in which the compressor is activated to perform a supply of compressed air to a vehicle compressed-air system.