An oil state detection device includes an index member, a lighting device that illuminates the index member, and a photographing device that photographs the index member through oil in a machine device.

An oil state detection device includes an index member, a lighting device that illuminates the index member, and a photographing device that photographs the index member through oil in a machine device.

A hydraulic system for powering a winch assembly of a work machine includes a hydraulic reservoir, a pump, a cooling system, a first path of travel, and a second path of travel. The first path of travel is disposed between the pump and the cooling system, and the winch assembly is powered by the hydraulic fluid moving along the first path of travel. The second path of travel is disposed between the pump and the cooling system. When the winch assembly is in an active condition, a first valve is in an open position such that the hydraulic fluid moves along the first path of travel and through the cooling system. When the winch assembly is in an idle condition, a second valve is in an open position such that the hydraulic fluid moves along the second path of travel and through the cooling system.

The present disclosure provides a heat exchanger system for a servovalve, comprising a base comprising a supply port in fluid communication with a return port, a first passage for fluid connection to a source of cooling fluid, and a second passage in fluid communication with the return port. The system further comprises one or more pipes located over a surface of the base, the one or more pipes fluidly connected between the first passage and the second passage, such that in use cooling fluid may flow from the first passage to the second passage via the network of pipes.

A working machine comprising a hydraulic fluid circuit an operator structure and a thermal management system. The thermal management system connects an operator structure heater and a heat exchanger arranged to selectively remove heat energy from the hydraulic fluid circuit, so as to be capable transferring heat from the hydraulic fluid to the operator structure.

A working machine having a thermal management system with an energy distribution system to selectively transfer thermal energy between an operator structure and a hydraulic fluid, based on the relative values of an operator structure energy requirement and a hydraulic fluid energy requirement.

An aircraft hydraulic fluid heating system and method are disclosed. In one embodiment, pump characteristics of a hydraulic pump coupled to a reservoir are obtained. Further, total demand of the hydraulic fluid for hydraulically controlled flight controls in the aircraft is determined. Furthermore, the hydraulic fluid in the reservoir is dynamically heated based on the pump characteristics and the total demand of the hydraulic fluid.

An air cylinder fluid circuit is formed by connecting a switching valve, which switches the supply and discharge of compressed air, and cylinder port parts of an air cylinder by means of pipes, wherein the acoustic velocity conductance of the pipes is smaller than the acoustic velocity conductance of the switching valve and the cylinder port parts.

An air vent hole includes a substantially columnar hole main body portion, a first hole portion formed on the upper side of the hole main body portion, and a second hole portion formed on the lower side of the hole main body portion. Each of the first hole portion and the second hole portion partly has, in a cross section of the hole portion substantially orthogonal to a first direction that is a longitudinal direction of the hole main body portion, a cross-sectional area smaller than a cross-sectional area of a cross section of the hole main body portion substantially orthogonal to the first direction. A float inserted into the air vent hole is movable between a position where the float occludes the first hole portion and a position where the float occludes the second hole portion. The float occludes the first hole portion under the weight of the float. However, the float is pushed up by air. Furthermore, the float is formed of a material having a smaller specific gravity than a liquid to be filtered. Thus, the float is pushed up by the liquid to occlude the first hole portion.

An air vent hole includes a substantially columnar hole main body portion, a first hole portion formed on the upper side of the hole main body portion, and a second hole portion formed on the lower side of the hole main body portion. Each of the first hole portion and the second hole portion partly has, in a cross section of the hole portion substantially orthogonal to a first direction that is a longitudinal direction of the hole main body portion, a cross-sectional area smaller than a cross-sectional area of a cross section of the hole main body portion substantially orthogonal to the first direction. A float inserted into the air vent hole is movable between a position where the float occludes the first hole portion and a position where the float occludes the second hole portion. The float occludes the first hole portion under the weight of the float. However, the float is pushed up by air. Furthermore, the float is formed of a material having a smaller specific gravity than a liquid to be filtered. Thus, the float is pushed up by the liquid to occlude the first hole portion.