A drive motor for a suction device (400) or a machine tool in the form of a handheld power tool (200, 300) or a semi-stationary machine tool, wherein the drive motor (20, 120) includes a stator (80) having an excitation coil assembly (86) and a rotor (40, 140) having a motor shaft (30, 130), which is rotatably mounted around a rotational axis (D) on the stator or with respect to the stator (80) by means of a bearing assembly (24A) and passes through a shaft through-opening (42, 142) of a laminated core (41, 141) which is held on the motor shaft (30, 130) and is electrically insulated from the motor shaft (30, 130). It is provided that an insulation sleeve (60) is arranged between the motor shaft (30, 130) and the laminated core (41, 141), which is inserted into the shaft through-opening (42, 142) and has a socket (64) with an insertion opening (64A) through which the motor shaft (30, 130) is plugged into the socket along an insertion axis (S).