A trimmer head comprising: a housing (21, 22) designed to be coupled to a drive shaft to rotate with respect to a main axis (X)； a support device (31, 32) for a bobbin of cutting wire, whose support device (31, 32) is disposed within the housing (21, 22) and movable between a coupling position, in which it is integral with respect to the rotation, with the housing (21, 22), and a free position, in which, it is not integral, with respect to the rotation, with the housing (21, 22)； coupling means (41, 42) that are configured to make the housing (21, 22) and the support device (31, 32) integral, with respect to the rotation with each other, in the coupling position； coupling means (43) that are configured so as to allow the movement of the support device (31, 32) from the free position to the coupling position； release means (51, 52) configured to move the support device (31) from the coupling position to the free position, said release means (51, 52) which are activated as a result of centrifugal force due to the rotation of the trimmer head； characterized in that, the support device (31, 32) comprises a lower disk (31) and an upper disk (32) that are independent of each other.Un cabezal de recortadora que comprende: una carcasa (21, 22) diseñada para ser acoplada a un árbol de accionamiento para girar con respecto a un eje (X) principal； un dispositivo (31, 32) de soporte para una bobina de hilo de corte, cuyo dispositivo (31, 32) de soporte está dispuesto dentro de la carcasa (21, 22) y móvil entre una posición de acoplamiento, en la cual es solidario con respecto al giro, con la carcasa (21, 22), y una posición libre, en la cual, no es solidario, con respecto al giro, con la carcasa (21, 22)； medios (41, 42) de acoplamiento que están configurados para hacer que la carcasa (21, 22) y el dispositivo (31, 32) de soporte se solidaricen, con respecto al giro entre sí, en la posición de acoplamiento； medios (43) de acoplamiento que están configurados de manera que permit
