Patent ID: 11892375
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 4:
5. An inspection apparatus for inspecting an interior of a conduit and for determining abnormality associated with the conduit, comprising:
a water supplier configured to supply water from a tank to an interior of the conduit through a hose provided at a first end of the conduit;
an air releaser configured to release air at a second end of the conduit from the interior of the conduit to an outside of the conduit through an air vent tube of an air vent portion placed at the second end of the conduit until an air vent valve closes, wherein the second end is distinct from the first end, the air vent portion includes an air vent valve, and when the air vent valve of the air vent portion is closed the closed air vent valve prevents the air from being released to outside the conduit;
a pressurizer configured to increase a pressure of the interior of the conduit whose both ends are blocked at the first end and the second end by supplying the water and whose interior is filled with water; and
a pressure measurer configured to measure a pressure value of the interior of the conduit when pressurization ends and a pressure value of the interior of the conduit when a predetermined period of time elapses since stopping the resumed supplying of the water to detecting the abnormality of the conduit,
wherein the water supplier supplies water to the interior of the conduit until water that does not contain air is drained from the air vent tube,
wherein the predetermined period of time elapses while the conduit is blocked at the first end and the second end and without receiving further supply of the water, and
wherein the abnormality of the conduit is associated with a change of the pressure value of the interior of the conduit when the predetermined time lapses.