Contact apparatus and electromagnetic switch

An electromagnetic switch, comprising

• a driving apparatus;
• and
• a contact apparatus, wherein the contact apparatus further comprises:
• a hollow chamber with an opening disposed on one side,
• two fixed contacts disposed on a top part of the chamber, and
• a moving contact assembly disposed inside the chamber, wherein the top part of the chamber is away from the opening, the two fixed contacts extend into the chamber;
• and the moving contact assembly further comprises:
• an insulating part, made of plastic;
• a push rod, wherein one end of the push rod is mounted on a driving apparatus, and the other end of the push rod is mounted on the insulating part;
• a moving contact, mounted on one side that is of the insulating part and that is back to the push rod;
• and
• an elastic part, clamped between the insulating part and the moving contact, so that the moving contact is in contact with or separated from the two fixed contacts under the action of the push rod, wherein
• a plurality of spaced protrusions is disposed on an outer wall that is of the insulating part in an axial direction of the push rod and that is located between the moving contact and the push rod,
• the contact apparatus is disposed on the driving apparatus;
• and
• the driving apparatus controls opening and closing of the contact apparatus by using an electromagnetic field generated by a coil.