Assembly comprising brush cage and spiral spring, and corresponding brush-holder, electric motor and motor vehicle starter

An assembly comprising:

• a brush cage (13);
• and
• a spiral spring (36);
• the spiral spring (36) comprising an axis (Y), a wound part (37) wound around the axis (Y), and an arm (39) extending from an end of the wound part (37);
• the brush cage (13) comprising at least one lateral wall (26, 27) provided with an opening (43) for the passage of the arm (39) through the at least one lateral wall (26, 27) such that a distal end of the arm (39) supported on at least one part of an end face of a brush (15),
• the arm (39) comprising a first portion (391), a width (L5) of the first portion (391) measured along the axis (Y) is different from a width (L6) of the wound part (37) measured along the axis (Y) of the spiral spring (36),
• the wound part (37) of the spring (36) formed by a plurality of concentric turns (371) around the axis (Y),
• the width (L5) of the first portion (391) is different from a width of each of the concentric turns (371) of the wound part 37 of the spring 36 measured along the axis (Y).