Apparatus for and method of locating leaks in a pipe

Claim 2

In an apparatus for locating leaks in a pipe including a viewing device for providing an image, means for variably locating the viewing device in the pipe, means for indicating the location of the viewing device in the pipe, and means for displaying the image provided by said viewing device, means for accurately locating the viewing device relative to a leak in the pipe comprising focusing means associated with the viewing device for providing a sharp, preselected small depth-of-field focused image of a narrow portion of the interior of the pipe at a preselected distance from the focusing means whereby a leak may be sharply displayed only when the viewing device is accurately at said preselected distance therefrom to coincide with the sharp image of the focused pipe portion, said depth of field being less than approximately 4 inches.

Claim 3

The leak locating apparatus of claim 1 wherein said focusing means comprises an effectively long focal length lens.

Claim 4

The leak locating apparatus of claim 1 wherein the pipe is circular, the viewing device is arranged to view the pipe from the axis thereof, and said means for accurately indicating said, condition comprises a circle on the displaying means corresponding accurately to the circular shape of the sharp limited depth-of-field image of the interior surface of the pipe interior wall surface at said preselected distance from said lens.

Claim 5

The leak locating apparatus of claim 1 further including means associated with said displaying means for accurately indicating the condition wherein the image of the leak extends downwardly from the top of the sharp limited depth-of-field image of the pipe interior wall surface.

Claim 6

The leak locating apparatus of claim 4 wherein said means for accurately indicating said condition comprises a marking on the displaying means corresponding accurately to the top of said sharp limited depth-of-field image.

Claim 7

The leak locating apparatus of claim 4 wherein said means for accurately indicating said condition comprises a closed line on the displaying means corresponding accurately to the shape of the sharp limited depth-of-field image of the interior surface of the pipe interior wall surface at saiD preselected distance from said lens.

Claim 8

In an apparatus for locating leaks in a pipe including a television camera for providing an image, means for variably locating the camera in the pipe, means for indicating the location of the camera in the pipe, and a television receiver for displaying the image provided by said camera, means for accurately locating the camera relative to a leak in the pipe comprising: a long focal length lens in said television camera for providing a sharp, preselected small depth-of-field focused image of a narrow portion of the interior of the pipe at a preselected distance from the lens whereby a leak may be sharply displayed by said receiver only when the camera lens is accurately at said preselected distance therefrom to coincide with the sharp image of the focused pipe portion, said depth of field being less than approximately 4 inches; and indicium means on said receiver for indicating when a leak viewed by the camera originates at a point in said pipe spaced from said lens accurately said preselected distance.

Claim 9

In an apparatus for locating leaks in a pipe including a television camera for providing an image, means for variably locating the camera in the pipe, means for indicating the location of the camera in the pipe, and a television receiver for displaying the image provided by said camera, means for accurately locating the camera relative to a leak in the pipe comprising: a long focal length lens in said television camera for providing a sharp, preselected small depth-of-field focused image of a narrow portion of the interior of the pipe at a preselected distance from the lens whereby a leak may be sharply displayed by said receiver only when the camera lens is accurately at said preselected distance therefrom to coincide with the sharp image of the focused pipe portion, said depth of field being less than approximately 4 inches; and indicium means on said receiver for indicating when a leak viewed by the camera originates at a point in said pipe spaced from said lens accurately said preselected distance.

Claim 10

The leak locating apparatus of claim 7 wherein said pipe is circular, said lens is carried by said television camera to be axially centered in the pipe, and said indicium means comprises a circle displayed on the receiver to be viewed concurrently with the displayed image for accurately identifying in the image the sharply focused circular zone of the pipe interior wall surface.

Claim 11

The leak locating apparatus of claim 7 wherein said indicium means comprises a plurality of different size concentric circles displayed on the receiver for use in identifying images with corresponding different diameter pipes.