Casement window operating mechanism

An operating mechanism for casement windows and like swinging closures comprising a drive gear adapted to be mounted centrally of a window opening and having an operating arm which can swing through a sufficient arc of movement to operate a casement window sash in either left hand or right hand mode, an operator link coupled with said operating arm to be shifted thereby and carrying near opposite ends lateral locking projection means, a slide pivotally coupled with one end of the operator link and being engageable with a linear guide at the bottom of the window opening, a pivot link having one end pivotally coupled to said slide and adapted for attachment to the bottom of a casement window sash, and a stabilizer link having one end pivotally coupled to the pivot link near the end of the latter distant from the slide and adapted to have its opposite end pivotally attached to the bottom of the window opening, said locking projection means on one end portion of the operator link moving into engagement with the opposing edge of the stabilizer link during the final stages of window sash closing movement to boost such movement and to automatically lock the sash in the fully closed position.