Contact switching device

A contact switching device comprising:

• a first terminal;
• a first contact attached to the first terminal;
• a second terminal;
• and
• a base made of resin, the base including a first attachment portion to which the first terminal is attached, a second attachment portion to which the second terminal is attached, and a groove portion arranged between the first attachment portion and the second attachment portion,
• the groove portion having a shape in which an inside is larger than an entrance in a top surface of the base,
• the groove portion extending toward a side surface of the base along a surface of the base and opens at the side surface of the base, the top surface being separate or different from the side surface, and
• the groove portion further having a shape in which
• a width increases toward the side surface of the base, or
• a bottom surface of the groove portion is inclined so that a distance from the entrance increases toward the side surface of the base.