An electronically commutated external rotor motor, which includes: a bearing tube ; an internal stator , which is arranged on the bearing tube ; a bell-shaped external rotor having a rotor bell , which external rotor is separated by a magnetically active air gap from the internal stator and has a rotor base , wherein fan blades can be arranged on the outside of the rotor bell ; a shaft associated with the external rotor , which is rotatably mounted in the bearing tube ; which bearing tube has a rotor-proximal section, which extends in the axial direction up into the region of the rotor base . and which bearing tube has a rotor-remote section, which extends in the axial direction away from the rotor-proximal section; a flange provided on the rotor-remote section of the bearing tube ; and a seal element provided with a seal lip, which element is arranged between the flange and the outer rotor , wherein the seal lip interacts with the rotor bell , and wherein a printed circuit board is arranged between the internal stator and the flange , wherein the seal element is introduced into a seat , which is radially circumferential on an outside at a flange end of the end region of the flange facing toward the internal stator , between an extension formed by the rotor bell and the flange end , and the seal lip is formed as a flexible lip extending radially diagonally outward, which presses against a radial inside of the extension , wherein, during operation of the motor , the seal lip is pressed by a pressure difference (p2 - p1) generated by means of the fan blades against the inside of the extension , and wherein no moisture or dust can penetrate from the outside into the motor , since the seal lip is pressed against the extension . a bearing tube ; an internal stator , which is arranged on the bearing tube ; a bell-shaped external rotor having a rotor bell , which external rotor is separated by a magnetically active air gap from the internal stator and has a rotor base , wherein fan blades can be arranged on the outside of the rotor bell ; a shaft associated with the external rotor , which is rotatably mounted in the bearing tube ; which bearing tube has a rotor-proximal section, which extends in the axial direction up into the region of the rotor base . and which bearing tube has a rotor-remote section, which extends in the axial direction away from the rotor-proximal section; a flange provided on the rotor-remote section of the bearing tube ; and a seal element provided with a seal lip, which element is arranged between the flange and the outer rotor , wherein the seal lip interacts with the rotor bell , and wherein a printed circuit board is arranged between the internal stator and the flange , wherein the seal element is introduced into a seat , which is radially circumferential on an outside at a flange end of the end region of the flange facing toward the internal stator , between an extension formed by the rotor bell and the flange end , and the seal lip is formed as a flexible lip extending radially diagonally outward, which presses against a radial inside of the extension , wherein, during operation of the motor , the seal lip is pressed by a pressure difference (p2 - p1) generated by means of the fan blades against the inside of the extension , and wherein no moisture or dust can penetrate from the outside into the motor , since the seal lip is pressed against the extension . <EOS>