Abstract: A planet wheel carrier which includes first and second end-sections for supporting shafts of planet wheels of a planetary gear, the planet wheel carrier containing a support structure connected to the first and second end-sections and located between the first and second end-sections in the axial direction of the planet wheels and between the planet wheels in the circumferential direction of the planet wheel carrier. The first end-section is attached to the support structure so that at least part of the first end-section is non-destructively detachable from the support structure. This feature facilitates the maintenance of the planetary gear because, after removing the first end-section or its detachable part, the planet wheels can be removed and installed substantially easier than in cases where there is a traditional one-piece planet wheel carrier.

Abstract: A method for installing a rotor of an electrical machine is disclosed. The method comprises using axially directed guide bars (107-109) for keeping the rotor (102) centered with respect to a bore of a stator (101) during the installation of the rotor. The rotor has sliding surfaces so that it can be slid in the axial direction to its final position along the guide bars. The mechanical support structure (104) that supports bearings (105, 106) of the rotor are provided with supporting surfaces for being able to give mechanical support to the guide bars. The mechanical support structure (104) may comprise for example threaded holes to which threaded ends of the guide bars can be tightened. After the rotor has been moved to its final position and it is supported by the bearings, the guide bars are removed.

Abstract: A planet wheel carrier comprises first and second end-sections for supporting shafts of planet wheels (113-114) of a planetary gear so that geometrical rotation axes of the planet wheels are pithed at substantially uniform intervals on a periphery of a circle. The planet wheel carrier comprises a support structure connected to outer rims of the first and second end-sections and located between the first and second end-sections in the axial direction and between the planet wheels in the circumferential direction. The support structure is so far from the geometrical rotational symmetry axis of a sun shaft (111) of the planetary gear and the geometrical rotation axes of the planet wheels are so near to the rotational symmetry axis of the sun shaft that the diameter (D) of the planet wheels is capable of being at least 90% of a distance (d) between the geometrical rotation axes of adjacent planet wheels.

Abstract: A planet wheel carrier comprises first and second end-sections (102, 103) for supporting shafts of planet wheels (113-114) of a planetary gear. The planet wheel carrier comprises a support structure (104) connected to the first and second end-sections and located between the first and second end-sections in the axial direction of the planet wheels and between the planet wheels in the circumferential direction of the planet wheel carrier. The first end-section is attached to the support structure so that at least part of the first end-section is non-destructively detachable from the support structure. The fact that at least part of the first end-section can be detached from the support structure facilitates the maintenance of the planetary gear because, after removing the first end-section or its detachable part, the planet wheels can be removed and installed substantially easier than in cases where there is a traditional one-piece planet wheel carrier.

Abstract: An electromechanical device having a mechanical interface structure for connecting to an external rotating element, an electrical machine, and one or more gear stages on a mechanical power transmission path between the mechanical interface structure and a rotor of the electrical machine. The rotor of the electrical machine is supported by the frame of the gear stage directly connected to the rotor.

Abstract: A method for controlling lubrication of a gear unit, where the lubrication method of the gear unit is changed between circulating lubrication and splash lubrication during operation of the gear unit, wherein the temperature of the lubrication fluid is measured, and the change between circulation lubrication and splash lubrication is based on the measured temperature of the lubrication fluid. The invention also relates to such a gear unit.

Abstract: A method for controlling lubrication of a gear unit, in which method temperature of a lubrication fluid circulating in a lubrication channelling of a gear unit is measured, wherein the temperature of lubrication fluid is measured in at least two locations of the gear unit, and larger proportion of the lubrication fluid is directed to the warmer of the at least two locations and correspondingly smaller proportion of the lubrication fluid is directed to the colder of the at least two locations. The invention relates also to such a gear unit.

Abstract: A gear lubrication arrangement comprises a lubrication pump for circulating lubrication fluid. A power source coupled to the lubrication pump drives the lubrication pump, and a controller controls an output power of the lubrication pump. The gear lubrication arrangement comprises a pressure sensor disposed down-stream of the lubrication pump The pressure sensor is configured to measure a pressure of the lubrication fluid and to produce a pressure indication signal representative thereof. The controller is arranged to vary the output power of the lubrication pump at least partly on the basis of the pressure indication signal.

Abstract: A gear unit comprises shafts for connecting to an external mechanical system, at least one gear stage between the shafts, a lubrication pump for circulating lubricating oil through the at least one gear stage and bearings of the gear unit, a temperature sensor for measuring temperature of the lubricating oil and supplying a temperature signal, an electrical motor for driving the lubrication pump, and an electrical device for controlling the electrical motor so that torque directed to the lubrication pump is below a torque limit. The torque limit is determined dynamically on the basis of the measured temperature of the lubricating oil. This arrangement makes it possible to protect the lubrication pump against mechanical faults during a cold start process so that an unnecessarily strict torque limitation, which would slow down the cold start process, can be avoided.