A drive system for an aircraft such as a tiltrotor aircraft. The drive system includes first and second gearbox assemblies in mechanical communication with each other. A first lubrication system is associated with the first gearbox assembly and includes a bifurcated tank configured to contain a lubricant in an operating chamber including a lower sump and in an emergency chamber including an upper sump. A second lubrication system is associated with the second gearbox assembly. An emergency pump is in fluid communication with the emergency chamber. The emergency pump is configured to supply the lubricant to the first gearbox assembly from the emergency chamber responsive to a failure in the first lubrication system. In addition, the emergency pump is configured to supply the lubricant to the second gearbox assembly and to the operating chamber from the emergency chamber responsive to a failure in the second lubrication system.

A vehicle drive-force transmitting apparatus including: a differential ring gear that is to be rotated about a first axis; a pump that is to be driven when the differential ring gear is rotated; a casing that stores therein the differential ring gear and the pump; a pipe that is connected to the pump so as to supply oil sucked by the pump, to lubrication-required elements of the drive-force transmitting apparatus; a catch tank that is provided by a rib provided in the casing; and a guide way that is provided by a rib provided in the casing. The guide way is configured to guide the oil discharged from the pipe, to the catch tank.

A pump stage assembly including at least two pump suction stages and at least one pump pressure stage. The pump suction stages and the pump pressure stage are arranged spaced apart from one another in a pump housing PG and have a common drive shaft. The pump suction stages are formed by a first assembly of intermeshing external gearwheels that lie in a first plane, and the pump pressure stage is formed by a second assembly of intermeshing external gearwheels that lie in a second plane. A first delivery volume flow can be drawn in from a first region of a dry sump by a first pump suction stage, and a second delivery volume flow can be drawn in from a second region of the dry sump by a second pump suction stage. The two delivery volume flows intermix in the pump housing before they reach an oil tank.

A gear unit to be mounted in a vehicle includes a housing for storing oil, a partition disposed inside the housing, and a helical gear. The partition defines first and second oil chambers and has a through-hole allowing the first oil chamber to communicate with the second oil chamber. The helical gear disposed inside the first oil chamber rotates during running of the vehicle and has an angled tooth that draws inner and addendum circles defining a virtual circumferential plane. The through-hole coincides with a portion of the virtual circumferential plane in a direction parallel to a central axis of the helical gear. When the helical gear rotates in conjunction with the running of the vehicle, the oil flows from the second oil chamber into the first oil chamber so that an oil level of the first oil chamber becomes higher than that of the second oil chamber.

A drive train for a vehicle includes a drive shaft, a transmission, a differential, and a wheel drive shaft. An axle drive gear wheel of the differential and a gear wheel of the transmission, which mesh with one another are at least partially in the oil sump in a splashing fashion. An end plate has a bearing retainer for receiving a bearing. The efficiency of the drive train is increased and/or splashing losses are avoided by the end plate, which has a flange-like circumferential region extending radially in the direction of the oil sump. The end plate and/or the circumferential region is or are formed to divide the oil sump into a first and a second oil sump region.

Systems are provided for an axle housing comprising at least one dam. In one example, an axle housing, comprising a center portion including a cavity configured to house a differential assembly and at least one dam arranged in an arm portion that extends from the center portion and is configured to receive an axle shaft, wherein the at least one dam comprises a flow facilitating protrusion that extends from the dam panel in a direction away from the center portion.

A vehicle drive-force transmitting apparatus including: a differential ring gear that is to be rotated about a first axis; a pump that is to be driven when the differential ring gear is rotated; a casing that stores therein the differential ring gear and the pump; a pipe that is connected to the pump so as to supply oil sucked by the pump, to lubrication-required elements of the drive-force transmitting apparatus; a catch tank that is provided by a rib provided in the casing; and a guide way that is provided by a rib provided in the casing. The guide way is configured to guide the oil discharged from the pipe, to the catch tank.

A transmission device is provided having a transmission housing, a gear set received in the transmission device having a first gear wheel, which is rotatable about a first gear wheel axis, and a second gear wheel, which engages the first gear wheel and is rotatable abut a second gear wheel axis. In a lateral region of the first gear wheel, there is an oil guidance structure, which is designed as a component produced separately from the transmission housing, and comprises an orifice segment extending radially to the first gear wheel axis, and extends at least in part about the first transmission axis and forms a first lateral surface facing the gear wheel, leaving an intermediate space.

A gearbox comprising a gearbox housing at least partially surrounding a cavity, an oil sump connected to the gearbox housing and surrounding another cavity, and a separating element separating the cavity from the other cavity and having a passage through which oil located in the cavity is fed into the other cavity. The passage is arranged in a plane at an intersection line between a first oil level upper side and a second oil level upper side. The oil is fed from the cavity into the other cavity exclusively through the passage. The separating element has a passage section and a separating section, the passage section protrudes from the separating section in the radial direction.

A mechanical device lubrication level control system operates within a mechanical housing having a sump cavity and a lubricant director, where the lubricant director is located at the bottom of the housing. A mechanical gear set is located in the sump cavity and a lube tank is located in the lubricant director. There is located within in lube tank either a motor with a pump or an expandable air bladder that is inflatable by an air source. For the lube tank having the motor with the pump, the pump controls the lubricant within the sump cavity. For the lube tank having the expandable air bladder, the air source controls the lubricant within the sump cavity.