Manoeuvring element with integrated locking means

A maneuvering element consisting of a crank rotatable about an axis x-x provided at one end of a protruding handle and at an opposite end of hollow bush which is configured to actuate rotation of a transmission shaft about the axis x-x, and

• furthermore provided with a safety system located between said ends of the crank, consisting of button means housed in a cavity obtained in said crank for the actuation of a locking pin that selectively prevents or allows rotation of said crank,
• wherein with said button means there are associated retaining means of said locking pin axially controlled by said button means and apt to rotate between a fastening position whereby the locking pin is extended outwards of said crank to prevent rotation of said crank, and an unlocking position whereby the locking pin is retracted into said crank to allow rotation of said crank,
• wherein said retaining means consist of a rotating insert consisting of a centrally drilled, substantially cylindrical body, externally provided with equidistant pins, a top surface of which is angled with respect to a resting plane that is defined as perpendicular to the axis x-x,
• wherein said rotating insert centrally carries a bush internally housing a first spring body that maintains elastic engagement between said button means and rotating insert,
• wherein the engagement between said button means and retaining means further occurs through a drawing pin engaged with said button means,
• wherein said drawing pin is inserted into and coaxial with said locking pin and slidingly engaged in a central open bore of said locking pin, the central bore of said locking pin having a retaining bottleneck, said drawing pin having a base having a slightly larger diameter than that of said retaining bottleneck,
• wherein a second spring body is housed above said bottleneck to thereby maintain said locking pin under tension to thereby resiliently bias said locking pin outwards of said crank, and
• wherein translational movement of the button means in a direction along said cavity directly causes corresponding translational movement of each of the rotating insert, drawing pin, and locking pin along said direction, whereby a compression of the second spring body causes said locking pin to be displaced and extended outwards of said crank.