An automatic disconnect coupling includes a retainer and a biasing member. The biasing member is coupled to the retainer and is arranged to communicate excitation from a generator input member to the retainer. The retainer and the biasing member have a fundamental frequency tuned to the rotational speed of the generator input member to automatically disconnect the input member from a drive member when rotating unbalance of the input member exceeds a predetermined level.

An automatic disconnect coupling includes a retainer and a biasing member. The biasing member is coupled to the retainer and is arranged to communicate excitation from a generator input member to the retainer. The retainer and the biasing member have a fundamental frequency tuned to the rotational speed of the generator input member to automatically disconnect the input member from a drive member when rotating unbalance of the input member exceeds a predetermined level.

A power transmission device that transmits a rotational driving force outputted from a driving source to a target device to be driven includes: a driving rotor rotated by the rotational driving force; a driven rotor that rotates with a rotary shaft of the target device; and a connection member. The connection member has a plate shape extending perpendicular to the rotary shaft. The connection member is connected at least one of the driving rotor and the driven rotor, and is capable of connecting the driving rotor and the driven rotor to each other. The connection member has a through hole, and the driven rotor has an overlapping portion disposed overlapping with the through hole when viewed in the axial direction of the rotary shaft.

A power transmission device that transmits a rotational driving force outputted from a driving source to a target device to be driven includes: a driving rotor rotated by the rotational driving force; a driven rotor that rotates with a rotary shaft of the target device; and a connection member. The connection member has a plate shape extending perpendicular to the rotary shaft. The connection member is connected at least one of the driving rotor and the driven rotor, and is capable of connecting the driving rotor and the driven rotor to each other. The connection member has a through hole, and the driven rotor has an overlapping portion disposed overlapping with the through hole when viewed in the axial direction of the rotary shaft.

A safety device for a curtain controller is provided. The safety device comprises a base, a bead chain wheel, and a cover. A shaft sleeve having a conical shape is disposed in a through hole of the base to connect a shaft's terminal and thus be fixed in a sleeving hole, having a shape to fit the shaft sleeve, of the bead chain wheel, so that the motions of the shaft sleeve and the bead chain wheel are linked. A bead chain is wound on the bead chain wheel. When the bead chain is pulled down, the shaft sleeve can drive the rotation of the bead chain wheel. The upper part of the cover is pivotally connected to the base, and the lower part of the cover buckles the base. Therefore, when the bead chain is instantly pulled down, the cover can be opened to drop the bead chain wheel.

A safety device for a curtain controller is provided. The safety device comprises a base, a bead chain wheel, and a cover. A shaft sleeve having a conical shape is disposed in a through hole of the base to connect a shaft's terminal and thus be fixed in a sleeving hole, having a shape to fit the shaft sleeve, of the bead chain wheel, so that the motions of the shaft sleeve and the bead chain wheel are linked. A bead chain is wound on the bead chain wheel. When the bead chain is pulled down, the shaft sleeve can drive the rotation of the bead chain wheel. The upper part of the cover is pivotally connected to the base, and the lower part of the cover buckles the base. Therefore, when the bead chain is instantly pulled down, the cover can be opened to drop the bead chain wheel.

A safety coupling has a driving coupling member engaged with a driven coupling member by a frictional connection. The frictional connection can be disconnected by activation of a release element. The release element can be activated by a centrifugal device wherein a centrifugal unit of the centrifugal device is radially moveable to interact with a shift gate in dependence of the revolution speed of the centrifugal unit and the slip between the driving coupling member and the driven coupling member. The centrifugal device includes a stop to limit the centrifugal force applied to the centrifugal unit.

A safety coupling has a driving coupling member engaged with a driven coupling member by a frictional connection. The frictional connection can be disconnected by activation of a release element. The release element can be activated by a centrifugal device wherein a centrifugal unit of the centrifugal device is radially moveable to interact with a shift gate in dependence of the revolution speed of the centrifugal unit and the slip between the driving coupling member and the driven coupling member. The centrifugal device includes a stop to limit the centrifugal force applied to the centrifugal unit.

A shaft can include a first portion comprising a first material having first material properties, a disconnect portion comprising at least some of a second material having second material properties, and a third portion comprising a third material having third material properties. The disconnect portion can be positioned between the first portion and the third portion, the three material properties being configured such that the first portion is physically disconnected from the third portion in response to failure of the disconnect portion under at least one of a mechanical load and/or an electrical load and/or thermal load.

A protection system of a railway vehicle traction system includes an electric motor and an electrical power supply circuit. The system further includes: a mechanical coupler between first and second components of a transmission line, the first component being connected to an output shaft of the electric motor and the second component being connected to an input shaft of an axle of the railway vehicle, the coupler being able to be in an engaged or disengaged state; and a controller able to apply a disengagement signal to the coupling signal, to switch from the engaged state to the disengaged state if a failure of the power supply circuit and/or the electric motor is detected.