A press fit connection technology, which does not involve soldering, is known as a method of connecting a terminal to a circuit board. A press fit connection is made by press fitting a male terminal into a female terminal provided to the circuit board. Furthermore, a connection state between the male terminals and the female terminals is checked to determine whether the male terminals are connected to the female terminals in a normal way by measuring an insertion load, which is required to press fit the male terminals into the female terminals (see, for example, JP H08-330792A).
However, in a case where the male terminals are press fitted into the female terminals at once, a variation in the required insertion load, which is required to press fit each of the male terminals into the corresponding one of the female terminals, adds up, so that a variation in the entire insertion load of the male terminals becomes large. In such a case, even when the connection state of one or more of the male terminals is unacceptable, the measurement value of the insertion load of the one or more male terminals is hidden in the variation in the entire insertion load of the male terminals. Thereby, in such a case, it is not possible to check whether all of the male terminals are press fitted into the female terminals in a normal way.
Particularly, in a case of a drive apparatus (an actuator), in which an electric motor and a controller are assembled together, motor lines, which extend from the electric motor, are press fitted into connection terminals provided to a circuit board of the controller. At this time, the connection terminals are covered with a cover of the controller in many cases. Thereby, in such a case, the connection state of the motor lines cannot be visually checked. Thus, it is important to enable accurate check of whether all of the motor lines are press fitted into the connection terminals in a normal way through measurement of the insertion load.