Driving unit of a welding equipment

A driving unit of a welding equipment provided with a pressure application shaft that is driven by a motor comprising:

• a rotary shaft of the motor formed of a hollow shaft;
• a screw shaft fixed inside the rotary shaft;
• a nut fixed to the pressure application shaft, said nut being screw engaged with a screw provided on the screw shaft, and the rotary shaft of the motor being substantially coaxially positioned with the screw shaft;
• a driven part provided on the screw shaft and positioned between the rear of a body of the motor and the front of a position detector for transmitting the torque of the motor;
• and
• a manually operating driving part positioned eccentrically from the screw shaft for transmitting a turning torque to the driven part;
• wherein outer diameters of the nut and pressure application shaft are respectively smaller than an inner diameter of the rotary shaft to form a direct moving guide part, and the direct moving guide part is movable on an inner peripheral surface of the rotary shaft and a rotary motion of the rotary shaft of the motor is converted into a reciprocating motion.

A driving unit for welding equipment driven by a motor comprising:

• a hollow rotary shaft of the motor;
• a force application shaft capable of axial movement;
• a screw shaft fixed to said rotary shaft and positioned coaxially within said rotary shaft;
• and
• a nut fixed to said force application shaft, at least a portion of said nut being positioned coaxially inside said rotary shaft, an inner periphery of said nut threadably engaging an outer periphery of said screw shaft;
• wherein said motor operates to rotate said rotary shaft and said screw shaft to advance or retract said force application shaft in an axial direction.