Methods and apparatus related to electrolaminate clutches and transmissions are disclosed. A device can include: an input shaft that can be coupled to an electrolaminate sheet; an output shaft that can be coupled rigidly to a spring positioned over the input shaft, where the spring includes a tab that fits a groove of a spring capture ring that can be positioned over the input shaft; and a drum connected to an electrical ground between the electrolaminate sheet and the spring capture ring, where the drum can be coupled rigidly to the spring capture ring. Then, when a voltage is applied to the electrolaminate sheet, the electrolaminate sheet can clamp to the drum and impart rotation of the input shaft to the drum. The imparted rotation can cause the spring capture ring and the spring to rotate and clamp down on the input shaft, imparting rotation to the output shaft.

A decoupler assembly for disengaging a shaft transmitting torque between a rotatory engine and an electric generator. The decoupler assembly includes an output shaft, input shaft wherein the output shaft is selectively coupled to the input shaft. Retractable balls are incorporated into the assembly in order to couple and decouple the input shaft from the output shaft.

In an aspect, a clutched device is provided, including a hub, a pulley and a roller clutch. The roller clutch includes at least one roller and a cage. The roller is engageable with a first engagement surface operatively associated with the hub and is engageable with a second engagement surface operatively associated with the pulley. The cage is movable between a first position in which torque is transferrable from one of the hub and the pulley to the other of the hub and the pulley through the roller clutch and the isolation spring. The other of the hub and the pulley is permitted to overrun said one of the hub and the pulley, and a second position in which torque is transferred from said other of the hub and the pulley to the one of the hub and the pulley through the roller clutch.

In an aspect, a clutched device is provided, including a hub, a pulley and a roller clutch. The roller clutch includes at least one roller and a cage. The roller is engageable with a first engagement surface operatively associated with the hub and is engageable with a second engagement surface operatively associated with the pulley. The cage is movable between a first position in which torque is transferrable from one of the hub and the pulley to the other of the hub and the pulley through the roller clutch and the isolation spring. The other of the hub and the pulley is permitted to overrun said one of the hub and the pulley, and a second position in which torque is transferred from said other of the hub and the pulley to the one of the hub and the pulley through the roller clutch.

A wedge clutch, including: outer and inner races; a wedge plate radially between the inner and outer races; and an electromagnetic actuator. The electromagnetic actuator includes: a coil; a first coil core piece including a first end disposed within the coil and a second end connected to the wedge plate; and a second coil core piece including a first end disposed within the first coil and a second end connected to the wedge plate. In a locked mode of the clutch, the inner race and outer races and the wedge plate are non-rotatably connected for rotation of the inner race in a circumferential direction. In a free-wheel mode of the clutch, the inner race is rotatable, with respect to the outer race, in the circumferential direction. To transition from the locked mode to the free-wheel mode, the electromagnetic actuator is arranged to be energized to radially contract the wedge plate.

A clutch, including: inner and outer races; a wedge plate; an electromagnetic actuator including a coil and an attenuating circuit. The coil is arranged to be energized by a power source to switch the wedge clutch between: a locked mode in which the inner and races are locked in a circumferential direction and a free-wheel mode in which the inner race is rotatable with respect to the outer race in the circumferential direction. The attenuating circuit includes a capacitor parallel with the coil and a switch wired to the capacitor. During the free-wheel mode: the switch is arranged to connect the capacitor to an electrical ground; and the electrical power source is arranged to energize the coil and charge the capacitor with a voltage. Following initiation of the locked mode: the switch isolates the capacitor from the electrical ground; and the capacitor discharges the voltage through the coil.

A thermal fuse activation assembly for a clutch includes a thermal fuse. The thermal fuse has a body containing a temperature sensitive member. The temperature sensitive member is configured to activate upon a predetermined temperature. The thermal fuse activation assembly further includes a heat sink is thermally coupled to the thermal fuse.

A thermal fuse activation assembly for a clutch includes a thermal fuse. The thermal fuse has a body containing a temperature sensitive member. The temperature sensitive member is configured to activate upon a predetermined temperature. The thermal fuse activation assembly further includes a heat sink is thermally coupled to the thermal fuse.

A wedge clutch, including: outer and inner races; a wedge plate radially between the inner and outer races; and an electromagnetic actuator. The electromagnetic actuator includes: a coil; a first coil core piece including a first end disposed within the coil and a second end connected to the wedge plate; and a second coil core piece including a first end disposed within the first coil and a second end connected to the wedge plate. In a locked mode of the clutch, the inner race and outer races and the wedge plate are non-rotatably connected for rotation of the inner race in a circumferential direction. In a free-wheel mode of the clutch, the inner race is rotatable, with respect to the outer race, in the circumferential direction. To transition from the locked mode to the free-wheel mode, the electromagnetic actuator is arranged to be energized to radially contract the wedge plate.

A surgical microscope apparatus includes a stand base to which a stand post is fixed. The stand post supports a stand body so that the stand body horizontally turns around the stand post without turning the stand post. The stand body, therefore, is turnable with small force. Load applied to a rotary part at a top part of the stand post is only the weight of the stand body, and therefore, a bearing of the rotary part can be downsized.