Hydraulically actuatable work device designed to be handheld

A hydraulically activatable working device for performing a working operation, comprising

• a hydraulic cylinder;
• a first partial piston within the hydraulic cylinder and movable relative thereto, the first partial piston having a first impact surface at a lower end thereof and a first transfer surface at an upper end thereof;
• a second partial piston seated within a passageway of the first partial piston, the second partial piston having a second impact surface at a lower end thereof and a second transfer surface at an upper end thereof;
• a third partial piston seated within a passageway of the second partial piston, the third partial piston having a third impact surface at a lower end thereof and a third transfer surface at an upper end thereof, and
• wherein the first, second and third partial pistons are configured to telescope relative to each other such that the partial pistons are movable relative to each other and movable relative to the hydraulic cylinder;
• a hydraulic chamber provided between the hydraulic cylinder and the lower ends of the first, second and third partial pistons, the hydraulic chamber configured to receive a hydraulic fluid therein, wherein the hydraulic fluid acts against the first, second and third impact surfaces upon pressurization of the hydraulic fluid in the hydraulic chamber to cause the first, second and third partial pistons to move relative to the hydraulic cylinder in a traversing direction during the working operation;
• a piston rod within the hydraulic cylinder which is a separate component from the first, second and third partial pistons, the piston rod having an impact surface at a lower end thereof which forms a first partial impact surface against which the first transfer surface acts, a second partial impact surface against which the second transfer surface acts, and a third partial impact surface against which the third transfer surface acts,
• wherein the first, second and third transfer surfaces are engaged against the first, second and third partial impact surfaces of the piston rod in a first condition during the working operation, wherein only the second and third transfer surfaces are engaged against the second and third partial impact surfaces of the piston rod in a second condition during the working operation, and wherein only the third transfer surface is engaged against the third partial impact surface of the piston rod in a third condition during the working operation, and
• wherein the hydraulic fluid acts on the first, second and third impact surfaces at the same hydraulic pressure;
• a tool coupled to the piston rod and movable therewith;
• and
• a return spring within the hydraulic cylinder, the return spring biasing the first, second and third partial pistons in a direction opposite to the traversing direction, wherein the first, second and third partial pistons are movable in the traversing direction against the bias of the return spring.

A hydraulically activatable working device for performing a working operation, comprising:

• a hydraulic cylinder;
• a first partial piston within the hydraulic cylinder and movable relative thereto, the first partial piston having a first impact surface at a lower end thereof and a first transfer surface at an upper end thereof;
• a second partial piston within the hydraulic cylinder, the second partial piston being movable relative to the hydraulic cylinder and movable relative to the first partial piston, the second partial piston having a second impact surface at a lower end thereof and a second transfer surface at an upper end thereof;
• a hydraulic chamber provided between the hydraulic cylinder and the lower ends of the first and second partial pistons, the hydraulic chamber configured to receive a hydraulic fluid therein, wherein the hydraulic fluid acts against the first and second impact surfaces upon pressurization of the hydraulic fluid in the hydraulic chamber to cause the first partial piston to move relative to the hydraulic cylinder in a traversing direction for performing the working operation and to cause the second partial piston to move relative to the hydraulic cylinder and relative to the first partial piston in the traversing direction for performing the working operation, wherein the hydraulic fluid acts on the first and second impact surfaces at the same hydraulic pressure;
• a piston rod within the hydraulic cylinder which is a separate component from the first and second partial pistons, the piston rod having an impact surface at a lower end thereof which forms a first partial impact surface against which the first transfer surface acts and a second partial impact surface against which the second transfer surface acts, wherein the first and second transfer surfaces are engaged against the impact surface of the piston rod in a first condition during the working operation, and wherein the second partial piston extends upward from the first transfer surface such that only the second transfer surface is engaged against the impact surface of the piston rod in a second condition during the working operation;
• a tool coupled to the piston rod and movable therewith;
• and
• a return spring within the hydraulic cylinder, the return spring biasing the first and second partial pistons in a direction opposite to the traversing direction, wherein the first and second partial pistons are movable in the traversing direction against the bias of the return spring.