Patent ID: 8657033

Claim:
A grinder comprising: a cylindrical housing that accommodates a motor; a switch block that is assembled to a rear portion of the housing, and includes a switch that turns driving of the motor on and off; a controller that is assembled to the switch block, and includes a control circuit of the motor; a male terminal that is projectingly provided on one assembling surface of one of the switch block and the controller; a connection portion that is projectingly provided on the other assembling surface of the switch block and the controller, and accommodates a female terminal and includes an entry opening of the male terminal, wherein at the time of assembling of the switch block and the controller, the male terminal that enters from the entry opening is inserted into and connected to the female terminal; and a closing portion that is formed on the one assembling surface, and covers at least a formation surface of the entry opening of the connection portion with the male terminal in an inserted and connected state; wherein the male terminal, the female terminal, and the connection portion are configured to prevent particulate contamination.