An electromagnetic switch for a starter

The electromagnetic switch (8) for a starter, comprising: a housing (21), which serves as the outer frame of the electromagnetic switch (8) and forming a magnetic circuit; a core (18) which is fixed at one end of the housing (21); projecting a movable piston (11) which faces the core by means of an air gap (23) and from the other end of the housing (21); and a bobbin (14) in the housing (21) is arranged in such a manner that this part of the core (18) and the piston (11) surrounds, and around which an attracting coil (9) and a holding coil ( 10 are wound), wherein a magnetic bypass core (26) for diverting a portion of the magnetic flux, which shuts (of the piston 11) (the core 18), is arranged at a location (in a part of the bobbin 14) and is located in the produced no contact between the coil body (14) and the piston (11), wherein the magnetic bypass core (26) is disposed at a location which is located in an air gap portion (23) in a magnetic circuit through which the piston (11) moves due to the magnetic attractive force by exciting the attracting coil (9) and the holding coil (10) is produced, and which is located in such a manner between the outer periphery of the piston (11) and the inner periphery of the bobbin (14), that one end thereof with an end of the housing (21) comes into contact and the other end of which is the end of the core (18) faces by means of an air gap.