JPH0247245U - - Google Patents

Description

[Brief explanation of drawings]

FIG. 1 is a plan view showing an embodiment of the manhole cover device according to the present invention, FIG. 2 is an enlarged sectional view showing the locking mechanism thereof, and FIG.
FIG. 3 is a plan view of such a locking mechanism. Further, FIG. 4 is a sectional view showing a lock release jig suitably used when releasing the lock mechanism of the manhole cover device shown in FIG. 1, and FIG. It is a bottom view. Furthermore, FIG. 6 is a cross-sectional explanatory view of a main part showing another embodiment of a lock mechanism structured according to the present invention, and FIG. 7 is a cross-sectional explanatory view for explaining the unlocking operation in such a lock mechanism. It is a diagram. 10: holder frame, 12: lid body, 14: lock mechanism,
20: Support part, 26: Mounting bracket, 28: Locking bracket, 38: Engagement part, 48: Closure body, 50: Divided hole (mounting bracket 26 side), 52: Divided hole (locking bracket 28 side), 54: Cylinder, 56: Locking rod,
58: Lock release jig, 68: Permanent magnet.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A lid that is disposed within the frame of a receiving frame fixed to the manhole opening and that is capable of being engaged and detached from the receiving frame with respect to a cover that opens and closes the opening of the receiving frame. A locking member provided with an engaging protrusion is provided so as to be rotatable around an axis substantially perpendicular to the plate surface of the lid body, and the engaging protrusion is engaged with the receiving frame based on the rotational operation of the locking member, In such a manhole cover device that prevents the opening operation of the lid, the locking member is located at a rotational position relative to the locking member and the lid at which the engaging protrusion is engaged with the receiving frame. are provided with dividing holes communicating with each other to form a cylinder extending linearly between the locking member and the lid, and being movably housed within the cylinder,
At the moving position on one end side, the locking member is positioned across the split hole between the locking member and the lid body to prevent the locking member from moving, and at the moving position on the other end side, the locking member and the lid body are separated. A locking rod, at least a portion of which is made of a magnetic material, is arranged to allow rotation of the lock member by being accommodated in one of the split holes, and further, the locking rod is disposed within the cylinder. , configured to be held in the position of movement toward the one end and to allow the locking rod to be moved toward the other end by a magnetic force applied to the locking rod from the outside. A manhole cover device characterized by: (2) A biasing means for biasing the locking rod toward one side in the cylinder is provided, and the locking rod is held at the one end side, and at least the front of the locking rod in the biasing direction is provided. The end portion is formed of a magnet, and by applying a repulsive force to the locking rod by an external magnetic field, the locking rod can be moved to the other end side within the cylinder. The manhole cover device according to claim (1). (3) The cylinder is formed in a direction perpendicular to the plate surface of the lid, and the locking rod straddles between the dividing hole between the locking member and the lid at a position of movement toward the lower end of the cylinder. The locking rod is configured so that it can be housed in a split hole in either the locking member or the lid at the position where the locking rod is moved toward the upper end side of the cylinder, and the locking rod is moved into the cylinder by gravity. Claim characterized in that the locking rod is held at the lower end side and can be moved to the upper end side within the cylinder by applying an attractive force by an external magnetic field to the locking rod. The manhole cover device described in item (1).