PURPOSE: To increase the function speed of a dobby of a weaving loom compared with old-type dobby by inserting an assisting means.

CONSTITUTION: The objective dobby for weaving loom is composed of a series of actuation elements 1 depending on a weaving program incorporated in a reading device and coupled to traction levers 3 connected by a drawing system 8 to heddle frames 9. An arm 5 to be combined with the actuation element 1 is inserted between the traction lever 3 and at least certain of traction apparatuses 8 of the actuation element 1, the means is synchronized with the controlling cycle of the actuation element 1 to transmit the periodic oscillation motion to the arm, and the arm is pivotally supported by the traction lever 3 so as to follow the oscillation motion of the lever 3 at one of both positions in the stroke of the lever.