Abstract: An over-center handle mechanism is provided to operate electrical equipment, such as a switch or breaker, housed in an electrical enclosure. The over-center handle mechanism includes an adaptor knob, a rotary actuator and a spring. The adaptor knob interfaces with the electrical equipment. The rotary actuator is connected to the adaptor knob, and includes a cam. A through-door handle is used to operate the rotary actuator, which in turn operates the electrical equipment via the adaptor knob. To optimize an angular torque feeling at the through-door handle, the over-center handle mechanism further includes the spring to provide an opposing force against movement of the cam of the rotary actuator, and thus, the through-door handle. A solid lubricant of PTFE may also be provided as an interface between the cam and the spring to reduce friction therebetween.

Abstract: An over-center handle mechanism is provided to operate electrical equipment, such as a switch or breaker, housed in an electrical enclosure. The over-center handle mechanism includes an adaptor knob, a rotary actuator and a spring. The adaptor knob interfaces with the electrical equipment. The rotary actuator is connected to the adaptor knob, and includes a cam. A through-door handle is used to operate the rotary actuator, which in turn operates the electrical equipment via the adaptor knob. To optimize an angular torque feeling at the through-door handle, the over-center handle mechanism further includes the spring to provide an opposing force against movement of the cam of the rotary actuator, and thus, the through-door handle. A solid lubricant of PTFE may also be provided as an interface between the cam and the spring to reduce friction therebetween.

Abstract: A bi-directional torque-limiting interface for rotary operating devices is shown and described. The interface includes a first section receiving torque from a source, a second section delivering the received torque to a rotary operating device and a coupler operably connecting the first and second sections. The coupler is preloaded to a predetermined value and maintains a particular angular relationship between the first and second sections under normal operating conditions.