Automatic clamping gun without clamping jaw

The invention belongs to the field of liquid injection equipment, and discloses a claw-free automatic tightening gun which comprises a gun handle, a valve body channel, a tightening mechanism and an oil pot opening, and the claw-free automatic tightening gun is composed of the gun handle, the valve body channel and the tightening mechanism; one end of the gun handle is in butt joint with one end of the valve body channel, an inner cavity of the gun handle is communicated with an inner cavity of the valve body channel, and a clamping mechanism is fixed to the bottom end of the valve body channel. The tightening mechanism is composed of an air cylinder, a first sealing ring, a second sealing ring, a piston, a third sealing ring, a fourth sealing ring, a locking nut, an upper locking ring, a locking sleeve, a lower locking ring, a filling pipe and a fifth sealing ring, and the bottom end of the filling pipe extends into the oil pot opening. The oil can clamping device has the advantages that an oil can without a