To provide the key cover of a manhole cover and the locking device of the manhole cover using the key cover capable of surely and strictly locking the manhole cover in a simple constitution, easily unlocking it by only a permitted person or group, and easily adding an electronic locking mechanism to the locking device of an existing manhole cover without having the electronic locking mechanism.
A cap receiving member 12 is fixed on the upper part of the outer periphery of the key holes 3b, 5b of a manhole inner cover 3 or a manhole cover 5, a key cover A is fitted toward the key holes 3b, 5b and a pin 11b is engaged with the engaging hole 12b of the cap receiving member 12 to lock the key cover A on the key holes 3b, 5b. A control chip 10 incorporated in a fitting part 9a receives an unlocking signal transmitted from the R/W terminal machine of the outside, the pin 11b is dragged in by a control signal transmitted from the control chip 10 to be slipped off from the engaging hole 12b, and access to the key holes 3b, 5b is made possible.
HIYOUDOU NAKAMARO
KATO TOSHINARI
