An electrical connection device is described which comprises a container comprising at least two seats, each seat being configured for containing an electrical connection element comprising a first contact element sliding contact element and a second sliding contact element, each connectable to a respective electric cable, and further comprising a tubular element inserted inside the container so that they can be rotated one with respect to the other, being the first sliding contact element integrally connected to the container and the second sliding contact element integrally connected to the tubular element to make a sliding contact between the contact elements.

An electrical connection device is described which comprises a container comprising at least two seats, each seat being configured for containing an electrical connection element comprising a first contact element sliding contact element and a second sliding contact element, each connectable to a respective electric cable, and further comprising a tubular element inserted inside the container so that they can be rotated one with respect to the other, being the first sliding contact element integrally connected to the container and the second sliding contact element integrally connected to the tubular element to make a sliding contact between the contact elements.

A rotating electrical machine and a method of manufacturing a rotating electrical machine. The machine including a machine frame, a rotor, a shaft attached to the rotor and bearings supporting the shaft and the rotor in the machine frame. The rotating electrical machine includes further an electrically conducting member having a hole, the electrically conducting member being attached to the frame such that the shaft extends through the hole.

An electrical contact device includes a high electric potential-side contact and a low electric potential-side contact having a lower electric potential than the high electric potential-side contact. The high electric potential-side contact and the low electric potential-side contact are configured to be brought into and out of contact with each other. At least one of the high electric potential-side contact and the low electric potential-side contact is formed of a low-boiling point material whose boiling point is lower than 2562° C. or a mixed material that contains the low-boiling point material.

An electrical contact device includes a high electric potential-side contact and a low electric potential-side contact having a lower electric potential than the high electric potential-side contact. The high electric potential-side contact and the low electric potential-side contact are configured to be brought into and out of contact with each other. At least one of the high electric potential-side contact and the low electric potential-side contact is formed of a low-boiling point material whose boiling point is lower than 2562° C. or a mixed material that contains the low-boiling point material.

Disclosed is a motor, the motor according to an exemplary embodiment of the present disclosure including a stator arranged at an inner surface of a housing and including a magnet, a rotor core centrally arranged at the stator to pass through a rotation shaft, a rotor including an insulator covering the rotor core and a coil wound on the insulator, a commutator coupled to the rotation shaft to be electrically connected to the coil, and a brush coupled to the housing to be closely contacted to the commutator, wherein the insulator is formed with a short-circuit prevention unit formed on a drop path of conductive particles in order to prevent the short-circuit between the rotor core and the commutator from being generated by the conductive particles generated by the commutator and the brush.

Disclosed is a motor, the motor according to an exemplary embodiment of the present disclosure including a stator arranged at an inner surface of a housing and including a magnet, a rotor core centrally arranged at the stator to pass through a rotation shaft, a rotor including an insulator covering the rotor core and a coil wound on the insulator, a commutator coupled to the rotation shaft to be electrically connected to the coil, and a brush coupled to the housing to be closely contacted to the commutator, wherein the insulator is formed with a short-circuit prevention unit formed on a drop path of conductive particles in order to prevent the short-circuit between the rotor core and the commutator from being generated by the conductive particles generated by the commutator and the brush.

A device (i.e., a slip-ring or a homopolar motor/generator) (40, 50, 80) is adapted to provide electrical contact between a stator and a rotor (41, 83), and includes: a current-carrying brush-spring (31, 84) mounted on the stator, and having two opposite surfaces; a fibrous brush assembly (35, 69) mounted on the conductor, the brush assembly having a bundle of fibers (36, 71) arranged such that the tips of the fibers will engage the rotor for transferring electrical current between the stator and rotor; a ribbon (33, 85) of superconducting material mounted on each opposite surface of the current-carrying brush-spring and communicating with the stator and the brush assembly; and another ribbon (29, 86) of superconducting material mounted on the rotor. The device is submerged in a cryogenic fluid at a temperature below the transition temperatures of the superconducting materials such that the electrical resistivity of the device will be reduced and the current-transfer capability of the device will be increased.

An electric motor has a commutator and at least one brush with a concavely curved brush surface as a running surface for the commutator. The brush has two parallel running in ribs, which protrude perpendicularly above the brush surface. The running in ribs each have a radius of curvature which is greater than a radius of curvature of a convex commutator surface. The running in ribs are arranged eccentrically and at a spacing from one another such that they are offset with respect to two opposing surface outer edges of the brush surface. The running in ribs are arranged such that they are inclined at an angle of inclination with respect to the surface outer edges.

In an assembly for electrically exciting the rotor of an electrical machine, the wear of the sliding contacts is reduced in operating conditions with low current density in that an AC current is injected. The additional injection of the AC current is superimposed upon the DC current. The rotor poles function as an open circuit with respect to the AC current through a co-rotating capacitor.