Closure apparatus for a housing for damping interference signals of a commutated electric motor

A closure apparatus (7) for a housing (3), in which a mechanically commutated electric motor (5) is at least partially arranged, the closure apparatus (7) comprising:

• a first rod-shaped inductor coil (19a) having a mid-axis (21a);
• a second rod-shaped inductor coil (19b), having a mid-axis (21b), around which coil wire is wound with a winding sense opposite the winding sense of the first rod-shaped inductor coil (19a), the first rod-shaped inductor coil (19a) and the second rod-shaped inductor coil (19b) being arranged parallel to one another in the closure apparatus (7);
• and
• a base (8) in which the first inductor coil (19a) and the second inductor coil (19b) are arranged along their mid-axes (21a, 21b) parallel to the base (8) on and/or at least partially in the base,
• wherein:
• the first inductor coil (19a) is coupled electrically directly to a first coupling element (20a) electrically coupled to the mechanically commutated electric motor (5), and the second inductor coil (19b) is coupled electrically directly to a second coupling element (20b) electrically coupled to the mechanically commutated electric motor (5), such that upon connection of the mechanically commutated electric motor (5) to the first and second coupling elements (20a, 20b) and during operation of the mechanically commutated electric motor (5), the magnetic fluxes (Φ1, (Φ2) in the first and second inductor coils (19a, 19b) at least partially compensate for one another, and
• the first inductor coil (19a) and the second inductor coil (19b) have an at least approximately identical inductor coil diameter (D), and the ratio of a distance (A) between the respective mid-axes (21a, 21b) of the first inductor coil (19a) and the second inductor coil (19b) to the inductor coil diameter (D) is greater than 1 and less than 1.8.