A fixed bracket for clamping to a square bar in articulated-arm awnings and securing the profile of the articulated arm to the square bar without adjustment mechanisms to compensate the arm inclination of the awning and comprising a body with: - a first front portion with a housing for coupling securely a mobile bracket by means of a rotating joint, said housing having a first axis (b) with respect to which said mobile bracket rotates once coupled to the fixed bracket, - a second rear portion, following the front portion, with two legs opposite each other, determining an inner gap between each other to house the square bar, said gap being formed by a front face, a lower face and an upper face including front, lower and upper supporting surfaces, respectively, said legs further comprising a tightening surface at the rear ends of the lower and upper faces, each upper and lower tightening surface comprising at least one hole with a common axis (t) suitable for the insertion of a securing element, which coincides with said common axis (t) and, prevents the square bar from coming out of the gap bringing the upper and lower faces of the legs closer to each other, and characterised in that - the common axis (t) is perpendicular to the first axis (b), - in a frontal rear view (FIG 5 and FIG 10) the common axis (t) passes through the horizontal projection of the upper supporting surface and of the lower supporting surface of the respective upper and lower faces of the gap, and - the supporting surfaces of the upper and lower faces are parallel and are inclined with respect to the first axis (b), when the square bar is in the gap with said supporting surfaces (16a, 16b) in contact with the square bar by the action of the securing element. - a first front portion with a housing for coupling securely a mobile bracket by means of a rotating joint, said housing having a first axis (b) with respect to which said mobile bracket rotates once coupled to the fixed bracket, - a second rear portion, following the front portion, with two legs opposite each other, determining an inner gap between each other to house the square bar, said gap being formed by a front face, a lower face and an upper face including front, lower and upper supporting surfaces, respectively, said legs further comprising a tightening surface at the rear ends of the lower and upper faces, each upper and lower tightening surface comprising at least one hole with a common axis (t) suitable for the insertion of a securing element, which coincides with said common axis (t) and, prevents the square bar from coming out of the gap bringing the upper and lower faces of the legs closer to each other, and characterised in that - the common axis (t) is perpendicular to the first axis (b), - in a frontal rear view (FIG 5 and FIG 10) the common axis (t) passes through the horizontal projection of the upper supporting surface and of the lower supporting surface of the respective upper and lower faces of the gap, and - the supporting surfaces of the upper and lower faces are parallel and are inclined with respect to the first axis (b), when the square bar is in the gap with said supporting surfaces (16a, 16b) in contact with the square bar by the action of the securing element.