Torque wrench as power wrench

A torque wrench, comprising:

• a drive motor with a predetermined speed and a predetermined motor output torque;
• an intermediate gearbox connected downstream of said drive motor and reduces an output speed of said drive motor with a predetermined reduction ratio;
• a bolting gearbox connected downstream of said intermediate gearbox and having a bolting tool part on an output side, said bolting gearbox reducing an output speed of said intermediate gearbox with a predetermined reduction ratio;
• a housing with at least one handle, said drive motor and said intermediate gearbox are disposed in said housing in sequence;
• said bolting gearbox being a planetary gearbox with an external ring gear with internal toothing, said external ring gear being rotatably mounted on said housing and having a radially projecting torque support foot which, during a bolting operation, pivots against a required fixed support point and supports there reaction forces occurring on said planetary gearbox;
• said drive motor being non-rotatably disposed and fixed in said housing and said intermediate gearbox being rotatably mounted in said housing and is non-rotatably connected to said external ring gear;
• the predetermined reduction ratio of said intermediate gearbox is in an order of 1:10, and/or said predetermined motor output torque of said drive motor is in an order of 1 Nm and an output torque of said intermediate gearbox is 10 Nm.

A method for performing a bolting operation, which comprises the steps of:

• providing a torque wrench, containing:
• a drive motor with a predetermined speed and a predetermined motor output torque;
• an intermediate gearbox connected downstream of the drive motor, and reduces an output speed of the drive motor with a predetermined reduction ratio;
• a bolting gearbox connected downstream of the intermediate gearbox and having a bolting tool part on an output side, the bolting gearbox reducing an output speed of the intermediate gearbox with a predetermined reduction ratio;
• a housing with at least one handle, in the housing the drive motor and the intermediate gearbox are disposed in sequence;
• the bolting gearbox being a planetary gearbox with an external ring gear with internal toothing, the external ring gear being rotatably mounted on the housing and having a radially projecting torque support foot which, during the bolting operation, pivots against a required fixed support point and supports there reaction forces occurring on the planetary gearbox;
• the drive motor is non-rotatably disposed and fixed in the housing and the intermediate gearbox is rotatably mounted in the housing and is non-rotatably connected to the external ring gear, so that, during the bolting operation, only the reaction forces occurring at the housing due to the drive motor have to be supported by an operator and/or the reaction forces occurring due to the intermediate gearbox are additionally supported by the torque support foot;
• the predetermined reduction ratio of the intermediate gearbox is in an order of 1:10, and/or the predetermined motor output torque of the drive motor is in an order of 1 Nm and an output torque of the intermediate gearbox is 10 Nm;
• and
• holding the housing by the operator at the at least one handle during the bolting operation and the reaction forces occurring at the housing are to be supported as rotational forces.