SHAFT DRIVE COUPLING AND METHOD OF RELEASING

摘要

A releasable pneumatically operated coupling for an industrial drive such as for a grinding mill. A variable speed motor has its output shaft provided with a flange rotating therewith on which are mounted a plurality of radially moveable arcuate elements having friction pads on their radially inner surfaces. An inflatable ring surrounds the arcuate elements and, upon inflation, urges the pads into driving contact with an annular friction surface on a coupling output shaft. The arcuate elements have U-shaped undercuts in the axial torque bar passages therethrough for stress relief. Separate speed sensors on the motor shaft and coupling output shaft provide signals to a comparator which, upon sensing a predetermined speed difference, provide a signal to an electrically operated valve which exhausts air pressure from the inflatable ring to release the coupling.

主权项

1. A releasable shaft coupling for an industrial drive comprising:
(a) a rotatable input shaft including a plurality of circumferentially disposed radially movable elements having driving friction surfaces thereon; (b) an inflatable operable upon fluid pressurization to effect radial movement of the radially movable elements; (c) a rotatable output shaft having annular driven friction surfaces thereon disposed about the driving friction surfaces; (d) a first speed sensor disposed for sensing the rotational speed of the input shaft and operable to provide electrical signal indicative thereof; (e) a second speed sensor disposed for sensing the rotational speed of the output shaft and provide an electrical signal indicative thereof; (f) a fluid pressure conduit connected to the inflatable and operable upon connection to a source of pressurized fluid to effect inflation of the inflatable, wherein, upon inflation thereof the radially movable elements are moved to force the driving friction surfaces into contact with the driven friction surfaces to effect rotary coupling of the input shaft to the output shaft; (g) an electrically actuated valve connected to the conduit and operable upon energization to effect depressurization of the inflatable; and, (h) a comparator connected for receiving the first and second sensor signals and operable upon detecting a predetermined speed difference of the input and output shaft to provide an output signal effecting energization of the valve and release of the coupling.