Pruning shears

Pruning shears comprising

• a cutting head with a spring-biased blade pivotally connected to a jaw about a pivot point, the jaw cooperating with the blade to sever a workpiece received in a bight formed by the jaw;
• the spring-biased blade being biased with a blade force;
• a drive mechanism connected to the cutting head;
• and
• an elongate housing connected to the drive mechanism;
• wherein the drive mechanism comprises a driving line arrangement comprising a driving line;
• wherein the drive mechanism comprises a tackle arrangement, and the tackle arrangement comprises:
• a first pulley rotatable relative to the drive mechanism about an axis and coupled to the blade;
• a second pulley rotatable relative to the drive mechanism about the axis and arranged to receive the driving line at least partly around the second pulley;
• and
• a sheave for supporting the driving line, the sheave being arranged so that the driving line runs from the second pulley at least partly around the sheave and at least partly around the first pulley;
• wherein the driving line is arranged to transmit forces between the first pulley, the second pulley and the sheave;
• and the drive mechanism comprises a rotation prevention means for preventing rotation of the second pulley in relation to the drive mechanism when a drawing torque is applied to the second pulley, wherein the drawing torque is greater than a threshold torque, resulting in the second pulley being stationary in relation to the drive mechanism and the first pulley rotating in relation to the drive mechanism.