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.

In order to effect a seal a porous material which comprises one side of two opposing surfaces is used to restrict and evenly distribute externally pressurized gas, liquid, steam, etc. between the two surfaces, exerting a force which is opposite the forces from pressure differences or springs trying to close the two faces together and so may create a non-contact seal that is more stable and reliable than hydrodynamic seals currently in use. A non-contact bearing is also disclosed having opposing surfaces with relative motion and one surface issuing higher than ambient pressure through a porous restriction, wherein the porous restriction is part of a monolithic porous body, or a porous layer, attached to lands containing a labyrinth, the porous restriction and lands configured to not distort more than 10% of a gap created from differential pressure between each side of the porous restriction.

A method for measuring a state of wear of a consumable friction element, a measuring device and a friction element, in particular a brush or the like. The measuring device includes a sensing device having a sensor. A magnetic field can be produced by means of the sensor, and the friction element can be moved in the magnetic field relative to the sensor. The measuring device comprises an indicator that can be attached to the friction element. The indicator comprises a ferromagnetic, antiferromagnetic and/or ferrimagnetic substance, and a change in the magnetic field can be detected by means of the sensing device as a result of a change in the position of the indicator relative to the sensor.

A method for measuring a state of wear of a consumable friction element, a measuring device and a friction element, in particular a brush or the like. The measuring device includes a sensing device having a sensor. A magnetic field can be produced by means of the sensor, and the friction element can be moved in the magnetic field relative to the sensor. The measuring device comprises an indicator that can be attached to the friction element. The indicator comprises a ferromagnetic, antiferromagnetic and/or ferrimagnetic substance, and a change in the magnetic field can be detected by means of the sensing device as a result of a change in the position of the indicator relative to the sensor.

The present disclosure relates to a conductive slip ring for logging while drilling (LWD) instrument. The present disclosure utilizes a mechanical conductive slip ring to solve the problems of transmission of electric power and signals between two structures that have relative rotation, and the conductive slip ring has a simple structure, doesn't involve any complex circuit, and has low cost and high reliability. With the conductive slip ring in the present disclosure, there is no power transmission efficiency problem or signal transmission error rate problem. The conductive slip ring has high temperature-resistant, pressure-proof, and vibration-roof abilities, and can be applied widely.

The present disclosure relates to a conductive slip ring for logging while drilling (LWD) instrument. The present disclosure utilizes a mechanical conductive slip ring to solve the problems of transmission of electric power and signals between two structures that have relative rotation, and the conductive slip ring has a simple structure, doesn't involve any complex circuit, and has low cost and high reliability. With the conductive slip ring in the present disclosure, there is no power transmission efficiency problem or signal transmission error rate problem. The conductive slip ring has high temperature-resistant, pressure-proof, and vibration-roof abilities, and can be applied widely.

The present invention is a sliding contact member, including a powder compact portion that contains an electrically conductive diamond and an electrically conductive binder, and is provided at least on a sliding contact surface of either or both of two sliding contact members slidably in contact with each other. The sliding contact members are applied to DC motors, generators and the like.

A brush device includes: a first and a second flange disposed side by side, each flange extending radially between a rubbing face intended to rub against a moveable element and a flange head intended to be connected electrically to another moveable element, a first plate rigidly fixed to the first flange only and extending tangentially above the head of the second flange, in such a way as to transmit, when this first plate is loaded by pressure unit, pressure forces on the second flange, a second plate, distinct from the first plate, rigidly fixed to the second flange only and extending tangentially above the head of the first flange in such a way as to bear on the first flange in the event of relative motion of the second flange with respect to the first flange towards the first moveable element.

Power tools with conductive couplings used with active injury mitigation technology are disclosed. Conductive couplings are particularly relevant to table saws, hand-held circular saws, track saws, miter saws, and band saws with active injury mitigation technology. Conductive couplings provide a mechanism through which an electrical signal can be coupled or imparted to a blade, and then monitored for changes indicative of human contact with the blade. An exemplary conductive coupling includes a brush that establishes an electrical connection with a moving part of a power tool, and the brush maintains contact with the moving part of the power tool during at least 40 hours of cumulative time when the motor is spinning the arbor and blade without an interruption in the electrical connection sufficient to trigger the reaction system. A conductive coupling may be two-sided compliant. A conductive coupling may connect to a motor shaft to minimize electrical noise.