Hole inspection method and hole inspection device

摘要

While an insert shaft (11) disposed with a wide angle lens (15) at a top end thereof is being inserted into a hole to inspect a wall surface of the hole on the basis of an image photographed through the wide angle lens (15), gas is injected into the innermost recess of the hole along the outer circumferential surface of the insert shaft (11) by a gas injection mechanism (19). The gas injection mechanism (19) is provided with a guide (13) configured to surround a top end portion of the insert shaft (11) and form a gas injection passage (R) extending in the longitudinal direction of the insert shaft (11) between the inner circumferential surface of the guide (13) and the outer circumferential surface of the insert shaft (11), and a gas supply unit (14c) configured to supply gas to an inner space of the guide (13).

主权项

1. A hole inspection method for inspecting a wall surface of a hole,
while an insert shaft disposed with a wide angle lens at a top end thereof is being inserted into the hole to inspect the wall surface of the hole on the basis of an image photographed through the wide angle lens, gas is injected from a bottom side of a top end portion of the insert shaft to flow over the top end portion of the insert shaft in a longitudinal direction of the insert shaft along an outer circumferential surface of the insert shaft toward the top end of the insert shaft, wherein the top end portion of the insert shaft includes the top end of the insert shaft, and the bottom side of the top end portion of the insert shaft is disposed at a position along the top end portion of the insert shaft that is spaced from the top end of the insert shaft, wherein the gas injection mechanism is provided with a guide configured to surround a top end portion of the insert shaft and form a gas injection passage extending in the longitudinal direction of the insert shaft with the outer circumferential surface of the insert shaft, and a gas supply unit configured to supply gas to an inner space of the guide and to inject gas to the gas injection passage.