The present invention relates to a method for increasing the efficiency of an energy transfer device (100) with which electrical energy is converted contactlessly into electrical energy with the aid of a magnetic field in order to electrically excite a rotor of an electrical machine, comprising the step of:

arranging an additional electrically conductive material layer (13) on at least one active part (12, 19, 35, 45) of the energy transfer device (100), wherein an active part of the energy transfer device (100) is a part of the energy transfer device (100) which is at least partially exposed to the magnetic field used for energy transfer, and wherein the electrical conductivity of the additional material layer (13) is greater than the electrical conductivity of the at least one active part (12, 19, 35, 45). Moreover, the invention relates to an energy transfer device (100) and to a use of an electrically conductive material.

The present invention relates to a method for increasing the efficiency of an energy transfer device (100) with which electrical energy is converted contactlessly into electrical energy with the aid of a magnetic field in order to electrically excite a rotor of an electrical machine, comprising the step of:

arranging an additional electrically conductive material layer (13) on at least one active part (12, 19, 35, 45) of the energy transfer device (100), wherein an active part of the energy transfer device (100) is a part of the energy transfer device (100) which is at least partially exposed to the magnetic field used for energy transfer, and wherein the electrical conductivity of the additional material layer (13) is greater than the electrical conductivity of the at least one active part (12, 19, 35, 45). Moreover, the invention relates to an energy transfer device (100) and to a use of an electrically conductive material.

A motor assembly for use with a power tool includes a motor housing, a brushless electric motor disposed at least partially in the motor housing, and a PCB assembly coupled to the motor housing. The PCB assembly includes a heat sink, a power PCB coupled to a first side of the heat sink, and a position sensor PCB coupled to a second side of the heat sink opposite the first side and in facing relationship with the motor.

A motor includes a stator including a stator core and teeth respectively protruding from the stator core in predetermined directions of protrusion, and coils respectively wound onto the teeth n (n is an integer of 3 or greater) turns including first to n-th turns. A k-th (k is an integer, 1<k<n) turn of each of the coils lies at a center of a range wound with each of the coils onto the teeth in a corresponding one of the directions of protrusion of the teeth from the stator core. Each of the first turn and the n-th turn when each of the coils is cut in a corresponding one of the directions of protrusion of the teeth is greater in cross-sectional area than the k-th turn.

One aspect of a motor of the present disclosure may include a rotor having a motor shaft disposed along a central axis extending in one direction, a stator facing the rotor via a gap in a radial direction, and a housing having an accommodating portion configured to accommodate the rotor and the stator, and to enable oil to be stored therein, wherein the housing comprises a lower wall portion facing a vertical-directional lower region in the inside of the accommodating portion, the lower wall portion comprises a cooling flow passage formed therein, and refrigerant flows in the cooling flow passage, and at least a portion of the cooling flow passage overlaps the vertical-directional lower region in the inside of the accommodating portion when viewed along a vertical direction.

One aspect of a motor of the present disclosure may include a rotor having a motor shaft disposed along a central axis extending in one direction, a stator facing the rotor via a gap in a radial direction, and a housing having an accommodating portion configured to accommodate the rotor and the stator, and to enable oil to be stored therein, wherein the housing comprises a lower wall portion facing a vertical-directional lower region in the inside of the accommodating portion, the lower wall portion comprises a cooling flow passage formed therein, and refrigerant flows in the cooling flow passage, and at least a portion of the cooling flow passage overlaps the vertical-directional lower region in the inside of the accommodating portion when viewed along a vertical direction.

There is provided a winding system for use in an electrical, electronic or electromagnetic device or component including: one or more set of windings, each set of windings including an electrically-conductive element arranged in a winding pattern with multiple turns, at least one pair of adjacent turns of the multiple turns being spaced apart to provide at least one channel therebetween for coolant fluid to flow therethrough; and a housing for housing the set of windings, the housing including a fluid inlet and a fluid outlet each in fluid communication with the at least one channel, the housing facilitating coolant fluid to flow from the fluid inlet to the fluid outlet, via the at least one channel in direct contact with exposed surfaces of the set of windings, the exposed surfaces at least partially defining the at least one channel.

A generator air gap baffle train assembly includes linearly aligned baffle segments, linearly aligned wedge blocks, and a tensioning rod. Each baffle segment includes a radially outer portion having an outer surface to interface with the axial slot and a side surface angled with respect to the outer surface and an axially aligned first thru bore and a radially inner portion which projects into an air gap. A pair of wedge blocks are positioned on opposing sides of the radially outer portion, each wedge block including a side surface that interfaces with the side surface of the radially outer portion so that the interfacing surfaces are in abutting contact and an outer surface that interfaces with the axial slot and a second thru bore axially aligned with the first thru bore of each baffle segment. The tensioning rod is enclosed by a non-conducting hollow tube spanning between adjacent baffle segments.

A method for cooling an electrical machine includes the following steps: guiding a coolant in an axial coolant supply line which is arranged in the rotor shaft, and conducting the coolant into an interior chamber of the electrical machine via a radial coolant supply line which is connected in a coolant-conducting manner to the axial coolant supply line. The electrical machine has an axial coolant supply line and at least one radial coolant supply line connected in a coolant-conducting manner to the axial coolant supply line, both of which are arranged in the rotor shaft. An interior chamber of the electrical machine is connected in a coolant-guiding manner to the radial coolant supply line.

A method for cooling an electrical machine includes the following steps: guiding a coolant in an axial coolant supply line which is arranged in the rotor shaft, and conducting the coolant into an interior chamber of the electrical machine via a radial coolant supply line which is connected in a coolant-conducting manner to the axial coolant supply line. The electrical machine has an axial coolant supply line and at least one radial coolant supply line connected in a coolant-conducting manner to the axial coolant supply line, both of which are arranged in the rotor shaft. An interior chamber of the electrical machine is connected in a coolant-guiding manner to the radial coolant supply line.