PURPOSE: To miniaturize an operating mechanism, and to store it in an appropriate part such as a pivoted window frame by moving two sliders in a direction opposite to each other by an endless toothed belt interposed therebetween.

CONSTITUTION: Two sliders 22, 23 slidable in the longitudinal direction are arranged in a casing 21. An endless toothed belt 24 which is engaged with toothed rack formations of the sliders 22, 23 and wound around two rollers 25 are fitted to both sliders 22, 23 through guide plates 29, 30. A handle is rotated to move the sliders 22, 23 in the direction opposite to each other through an end part 19 of a crank rod shrink-fitted between projections 31, 32 on the slider 23, and espagnolette bars 34, 39 fitted to extension parts 33, 38 are moved. A roller pin around which the toothed belt is wound may be erected perpendicular.