Abstract: A lubrication device for a helicopter including: an oil sump in which oil for lubrication is retained; a lubrication pump configured to suck the oil from the oil sump to discharge the oil; and a lubrication passage extending from the lubrication pump to a first lubrication target. The lubrication passage includes: a first supply port that supplies the oil to the first lubrication target; an oil reservoir provided upstream of the first supply port; and an opening provided upstream of the oil reservoir and above the oil reservoir. The first supply port is formed right above the first lubrication target.

Abstract: A transmission lubricating structure includes a power transmitting shaft, a main lubricating circuit, and an auxiliary lubricating circuit. The power transmitting shaft includes an ejection hole communicating an inside with an outside of the power transmitting shaft. The main lubricating circuit includes: a main nozzle having a nozzle hole through which lubricating oil supplied from a main tank is discharged to the internal space of the power transmitting shaft; and a hydraulic pump configured to supply the lubricating oil by pressure from the main tank to the main nozzle. The auxiliary lubricating circuit includes an auxiliary nozzle arranged lower than an auxiliary tank and higher than a lubrication target at the outside of the power transmitting shaft, the auxiliary nozzle being configured to drop the lubricating oil, supplied from the auxiliary tank by an own weight of the lubricating oil, toward the lubrication target.

Abstract: A transmission device includes a casing accommodating a transmission gear and having an oil sump for retaining oil. The oil in the oil sump flows from a lubrication pump through a lubrication passage and is injected to the transmission gear. A connection portion is provided in a part of the lubrication passage, which part is disposed outside the casing. A direction control valve is provided downstream of the lubrication pump and upstream of the connection portion in the lubrication passage with respect to a flow direction of the oil. The direction control valve is configured to open the lubrication passage when a hydraulic pressure in the lubrication passage exceeds a predetermined value and to close the lubrication passage when the hydraulic pressure is equal to or lower than the predetermined value.

Abstract: A transmission device includes a casing accommodating a transmission gear and having an oil sump for retaining oil. The oil in the oil sump flows from a lubrication pump through a lubrication passage and is injected to the transmission gear. A connection portion is provided in a part of the lubrication passage, which part is disposed outside the casing. A direction control valve is provided downstream of the lubrication pump and upstream of the connection portion in the lubrication passage with respect to a flow direction of the oil. The direction control valve is configured to open the lubrication passage when a hydraulic pressure in the lubrication passage exceeds a predetermined value and to close the lubrication passage when the hydraulic pressure is equal to or lower than the predetermined value.

Abstract: A transmission structure of a helicopter according to one aspect is a transmission structure that transmits power from a prime mover to a rotary wing in the helicopter. The transmission structure includes: a housing; an input shaft that transmits the power of the prime mover to a gear arranged in the housing; a bearing supporting the input shaft in the housing such that the input shaft is rotatable, the bearing including an annular inner ring that holds the input shaft, an annular outer ring that is arranged outside the inner ring in a radial direction and fixed to the housing, and rolling elements sandwiched between the inner ring and the outer ring; and a sleeve that is sandwiched between an inner peripheral surface of the inner ring and the input shaft and is lower in heat conductivity than the inner ring and the input shaft.

Abstract: A transmission cooling assembly of a helicopter includes: a transmission including a speed change structure that changes the speed of rotation produced by rotational power input from a prime mover and outputs the resulting rotational power and a housing accommodating the speed change structure; a cowl covering at least a part of an outer surface of the housing, with a gap defined between the cowl and the outer surface; and a flow structure that allows external air to flow through the gap.

Abstract: A transmission lubricating assembly of a helicopter includes: a transmission including a speed change structure that changes the speed of rotation produced by rotational power input from a prime mover and outputs the resulting rotational power and a housing accommodating the speed change structure; and a lubricator that lubricates the speed change structure. The lubricator includes a collector that collects a mist of a lubricating oil in an internal space of the housing and a dropper that is disposed below the collector and that applies droplets of the lubricating oil to the speed change structure, the droplets resulting from the collected mist being gathered under its own weight.

Abstract: A lubrication device for a helicopter including: an oil sump in which oil for lubrication is retained; a lubrication pump configured to suck the oil from the oil sump to discharge the oil; and a lubrication passage extending from the lubrication pump to a first lubrication target. The lubrication passage includes: a first supply port that supplies the oil to the first lubrication target; an oil reservoir provided upstream of the first supply port; and an opening provided upstream of the oil reservoir and above the oil reservoir. The first supply port is formed right above the first lubrication target.

Abstract: A lubrication device for a helicopter including: an oil sump in which oil for lubrication is retained; a lubrication pump configured to suck the oil from the oil sump to discharge the oil; and a lubrication passage extending from the lubrication pump to a first lubrication target. The lubrication passage includes: a first supply port that supplies the oil to the first lubrication target; an oil reservoir provided upstream of the first supply port; and an opening provided upstream of the oil reservoir and above the oil reservoir. The first supply port is formed right above the first lubrication target.

Abstract: A transmission lubricating structure includes: a main tank; an auxiliary tank; a common line to supply lubricating oil from the main or the auxiliary tank; a main line to introduce the lubricating oil in the main tank to the common line; an auxiliary line to introduce the lubricating oil in the auxiliary tank to the common line; a common nozzle configured to discharge the lubricating oil, supplied from the common line, to a transmission; a pump configured to supply the lubricating oil from the main tank to the common line; and a relay valve arranged lower than the auxiliary tank and higher than the common nozzle and provided upstream of the common line, the relay valve being configured to block the auxiliary line when the pump is operating and open the auxiliary line so the common line communicates with the auxiliary tank when the pump is in a stop state.

Abstract: A transmission lubricating structure includes a power transmitting shaft, a main lubricating circuit, and an auxiliary lubricating circuit. The power transmitting shaft includes an ejection hole communicating an inside with an outside of the power transmitting shaft. The main lubricating circuit includes: a main nozzle having a nozzle hole through which lubricating oil supplied from a main tank is discharged to the internal space of the power transmitting shaft; and a hydraulic pump configured to supply the lubricating oil by pressure from the main tank to the main nozzle. The auxiliary lubricating circuit includes an auxiliary nozzle arranged lower than an auxiliary tank and higher than a lubrication target at the outside of the power transmitting shaft, the auxiliary nozzle being configured to drop the lubricating oil, supplied from the auxiliary tank by an own weight of the lubricating oil, toward the lubrication target.

Abstract: A lubrication device for a helicopter including: an oil sump in which oil for lubrication is retained; a lubrication pump configured to suck the oil from the oil sump to discharge the oil; and a lubrication passage extending from the lubrication pump to a first lubrication target. The lubrication passage includes: a first supply port that supplies the oil to the first lubrication target; an oil reservoir provided upstream of the first supply port; and an opening provided upstream of the oil reservoir and above the oil reservoir. The first supply port is formed right above the first lubrication target.

Abstract: A transmission device includes a casing accommodating a transmission gear and having an oil sump for retaining oil. The oil in the oil sump flows from a lubrication pump through a lubrication passage and is injected to the transmission gear. A connection portion is provided in a part of the lubrication passage, which part is disposed outside the casing. A direction control valve is provided downstream of the lubrication pump and upstream of the connection portion in the lubrication passage with respect to a flow direction of the oil. The direction control valve is configured to open the lubrication passage when a hydraulic pressure in the lubrication passage exceeds a predetermined value and to close the lubrication passage when the hydraulic pressure is equal to or lower than the predetermined value.