An electric machine including a pulse inverter having a region with an oil space and busbars, wherein the electric machine is electrically connected to the pulse inverter by the busbars such that the busbars are electrically connected to a connection of the pulse inverter, wherein the busbars and the electric machine are cooled by oil, and wherein the oil for supplying and cooling the busbars is stored within the oil space in the region of the pulse inverter.

Various methods and systems are provided for a system for cooling an electric motor. The cooling system includes a primary coolant passage through a rotor shaft linked to a plurality of secondary passages though lamination stacks of a rotor configured to receive coolant at a central region of the lamination stacks.

Various methods and systems are provided for a system for cooling an electric motor. The cooling system includes a primary coolant passage through a rotor shaft linked to a plurality of secondary passages though lamination stacks of a rotor configured to receive coolant at a central region of the lamination stacks.

Methods and systems are provided for an electric axle in a vehicle. The electric axle comprises an electric motor having a stator and a rotor, a coolant manifold mounted to an end plate of the rotor, wherein the coolant manifold is configured to flow coolant to rotor coolant lines extending axially through the rotor, and a spray ring comprising coolant lines coupled to the coolant manifold, wherein coolant flowing from the coolant manifold to the spray ring flows in a direction angled to an axial direction, wherein the spray ring is positioned circumferentially about axial stator end windings.

Methods and systems are provided for an electric axle in a vehicle. The electric axle comprises an electric motor having a stator and a rotor, a coolant manifold mounted to an end plate of the rotor, wherein the coolant manifold is configured to flow coolant to rotor coolant lines extending axially through the rotor, and a spray ring comprising coolant lines coupled to the coolant manifold, wherein coolant flowing from the coolant manifold to the spray ring flows in a direction angled to an axial direction, wherein the spray ring is positioned circumferentially about axial stator end windings.

The invention discloses systems for improving performance and operational efficiency of wireline tractors. A cooling system improves power capabilities of electrical motors mounted in wheels, which are mounted on a linkage pivotably connected to an arm extended from a tractor tool body, in an in-line arm configuration. The linkage and arm mechanism significantly improve the tractor's ability to traverse wellbore obstructions. The hydraulic system of the tractor ensures adequate wellbore centralization.

The invention discloses systems for improving performance and operational efficiency of wireline tractors. A cooling system improves power capabilities of electrical motors mounted in wheels, which are mounted on a linkage pivotably connected to an arm extended from a tractor tool body, in an in-line arm configuration. The linkage and arm mechanism significantly improve the tractor's ability to traverse wellbore obstructions. The hydraulic system of the tractor ensures adequate wellbore centralization.

A vehicle drive device includes: a rotary electric machine; a drive transmission mechanism provided in a power transmission path connecting a rotor shaft of the rotary electric machine and a wheel; a first hydraulic pump driven by a driving force transmitted through the power transmission path; a second hydraulic pump driven by a driving force source independent of the power transmission path; a first oil passage that supplies oil discharged from the first hydraulic pump to a rotor bearing that supports the rotor shaft such that the rotor shaft is rotatable; and a second oil passage that supplies oil discharged from the second hydraulic pump to an inner peripheral surface of the rotor shaft.

A vehicle drive device includes: a rotary electric machine; a drive transmission mechanism provided in a power transmission path connecting a rotor shaft of the rotary electric machine and a wheel; a first hydraulic pump driven by a driving force transmitted through the power transmission path; a second hydraulic pump driven by a driving force source independent of the power transmission path; a first oil passage that supplies oil discharged from the first hydraulic pump to a rotor bearing that supports the rotor shaft such that the rotor shaft is rotatable; and a second oil passage that supplies oil discharged from the second hydraulic pump to an inner peripheral surface of the rotor shaft.

A shaft (12) for cooling an electric machine (10) includes: an outer sub-shaft (32), which is designed for being rotationally fixed to a rotor (14) of the electric machine; an inner sub-shaft (30), which is rotationally fixed to the outer sub-shaft and is designed as an output shaft of the electric machine; an inflow (36) arranged in the radial direction between the outer sub-shaft and the inner sub-shaft, in order to supply cooling fluid (28) to the shaft; and an outflow (42) arranged in the radial direction between the outer sub-shaft and the inner sub-shaft, in order to discharge cooling fluid supplied to the shaft. The outer sub-shaft encloses a fluid chamber (40), which is arranged in the axial direction between the inflow and the outflow. A direction of flow of cooling fluid in the fluid chamber is established by a delivery direction of a fluid pump (24).