Apparatus for sensing a curvature in a conduit

Claim 3

The method as defined in claim 1 including the step of pivotally interconnecting said components in tandem with a universal joint, whereby change in slope of said bore in any direction is detected.

Claim 6

The method as defined in claim 3 wherein said sEcuring step includes the step of positioning said rod in a predetermined angular relation to said rigid components whereby the relationship between the location of said orthogonal strain components and the rigid components is determined.

Claim 7

The method as defined in claim 4 including the step of detecting the instantaneous angular configuration of said rigid components in said bore, whereby the instantaneous angular location of said orthogonal strain components is determined.

Claim 10

The method as defined in claim 6 wherein said detecting step comprises detecting the strain in said rod along at least two planes located at 90* with respect to ach other to detect orthogonal components of the maximum strain in said rod.

Claim 11

The method as defined in claim 7 wherein said securing step includes the step of positioning said rod in a predetermined angular relation to said rigid components whereby the relationship between the location of said orthogonal strain components and the rigid components is determined.

Claim 12

The method as defined in claim 8 including the step of detecting the instantaneous angular configuration of said rigid components in said bore, whereby the instantaneous angular location of said orthogonal strain components is determined.

Claim 13

The method as defined in claim 9 including the step of securing a generally frustoconical housing to one of said rigid components at said universal joint, with said housing opening towards and receiving the adjacent end of the other of said components thereby to limit the total permissible bending angle between said rigid components.

Claim 14

The method as defined in claim 10 including the step of moving said interconnected rigid components through said pipeline to a plurality of measuring stations to determine the change in slope of said pipeline at each of said stations.

Claim 15

Apparatus for determining the change in slope of a bore, which apparatus comprises, a pair of elongated rigid components, means for pivotally interconnecting said components in tandem relation, said components each having a free end opposite said pivotal connection, means for supporting the free ends of each of said components and the pivotal connection therebetween on the centerline of said bore, an elongated flexible rod having opposed ends respectively secured to said rigid components and extending through the center of said pivot means, and means for detecting the strain in said rod at said pivotal interconnection, whereby said strain is proportional to the change in slope between said rigid components and the change in slope of said bore.

Claim 16

Apparatus for determining the change in slope of a bore, which apparatus comprises, a pair of elongated rigid components, means for pivotally interconnecting said components in tandem relation, said components each having a free end opposite said pivotal connection, means for supporting the free ends of each of said components and the pivotal connection therebetween on the centerline of said bore, an elongated flexible rod having opposed ends respectively secured to said rigid components and extending through the center of said pivot means, and means for detecting the strain in said rod at said pivotal interconnection, whereby said strain is proportional to the change in slope between said rigid components and the change in slope of said bore.

Claim 17

The apparatus as defined in claim 12 wherein said means for pivotally interconnecting said rigid components comprises a universal joint whereby said components may pivot in all directions with respect to each other and the change in slope of said bore in any direction is detected.

Claim 18

The apparatus as defined in claim 13 wherein said means for detecting strain comprises means for detecting the strain in said rod along at least two planes located at 90* with respect to each other to detect orthogonal components of the maximum strain in said rod.

Claim 19

The apparatus as defined in claim 14 including means for securing said flexible rod in said components in a predetermined angular relation whereby the relationship between said orthogonal strain components and said rigid components is determined.

Claim 20

The apparatus as defined in claim 15 including means for detecting the instantaneous angular relation of said rigid components with respect to said bore whereby the instantaneous angular location of said orthogonal components is determined.

Claim 21

Apparatus for determining the curvature and strain in a pipeline, said apparatus comprising, a pair of hollow elongated tubular components having cross-sectional areas substantially less than the cross-sectional area of said pipeline, a universal joint operatively interconnecting said components in tandem relation, said components each having an end portion opposite said universal joint and being spaced equi-distant therefrom, an elongated flexible strain rod having opposed ends respectively rigidly secured to said rigid components and extending through the center of said universal joint whereby substantially all bending strain at said joint caused by relative pivotal movement between said components occurs, means for supporting said free end portions of each of said components and said universal joint in concentric relation to said pipeline and on the centerline thereof, whereby the change in slope between said components at said universal joint is equal to the change in slope of said pipeline, and means for detecting the strain in said rod at said universal joint, said strain being proportional to the change in slope of said components and said pipeline and to the strain in said pipeline.

Claim 22

Apparatus for determining the curvature and strain in a pipeline, said apparatus comprising, a pair of hollow elongated tubular components having cross-sectional areas substantially less than the cross-sectional area of said pipeline, a universal joint operatively interconnecting said components in tandem relation, said components each having an end portion opposite said universal joint and being spaced equi-distant therefrom, an elongated flexible strain rod having opposed ends respectively rigidly secured to said rigid components and extending through the center of said universal joint whereby substantially all bending strain at said joint caused by relative pivotal movement between said components occurs, means for supporting said free end portions of each of said components and said universal joint in concentric relation to said pipeline and on the centerline thereof, whereby the change in slope between said components at said universal joint is equal to the change in slope of said pipeline, and means for detecting the strain in said rod at said universal joint, said strain being proportional to the change in slope of said components and said pipeline and to the strain in said pipeline.

Claim 23

Apparatus as described in claim 17 wherein said means for supporting said free end portions of said components and said universal joint comprises at least three separate carriage members mounted respectively on said tubular components adjacent said free end portions and said universal joint.

Claim 24

Apparatus as described in claim 18 wherein said carriage members each include a plurality of radially extending arms respectively mounted at one end to their associated tubular components and anti-friction means secured to the opposite ends of said arms for supporting said tubular components in said pipeline.

Claim 25

Apparatus as defined in claim 19 wherein the anti-friction means on the arms of the carriage members mounted adjacent the free end portions of said tubular members respectively lie in common planes extending perpendicularly to and intersecting their associated tubular members at points located equal distances from said universal joint, and the anti-friction means on the arms of the carriage member mounted adjacent the universal joint lie on a common plane extending perpendicular to the central axis of the tubular member to which their arms are connected and intersecting said universal joint at the center thereof whereby said points and the center of said joint are supported on the centerline of said pipeline.

Claim 26

The apparatus as defined in claim 20 wherein said arms are pivotally mounted on said tubular members and said carriage members include means for adjusting and maintaining the angular position of said arms with respect to their associated tubular members.

Claim 27

Apparatus as defined in claim 21 including means for continuously urging one of the arms in each of said carriage members outwardly about its pivotal mounting towards the inner wall of said pipeline.

Claim 28

Apparatus as defined in claim 21 wherein said means for detecting strain includes at least two strain gages secured to the periphery of said rod adjacent the center of said universal joint, with at least one strain gage located 90* away from the other of said strain gages thereby to detect orthogonal components of the maximum strain in saId rod.

Claim 29

Apparatus as defined in claim 23 including means for securing said flexible rod to said components in a predetermined angular relation whereby the relationship between said orthogonal strain components and said rigid components is determinable.

Claim 30

Apparatus as defined in claim 24 including means for detecting the instantaneous angular relation of said rigid components with respect to said pipeline whereby the instantaneous angular location of said orthogonal components is determinable.

Claim 31

Apparatus as defined in claim 25 wherein said means for detecting the instantaneous angular relation of said rigid components comprises a variable resistance annular potentiometer having a gravity activated slide contact and mounted in a predetermined position in one of said tubular members whereby a predetermined signal is produced by said potentiometer at each angular position of its associated tubular member about the centerline of said pipeline.

Claim 32

Apparatus as defined in claim 25 including a frustoconical collar secured in axial alignment to one of said tubular members, adjacent said universal joint, and opening outwardly thereof to surround a portion of the adjacent end of the other of said rigid components to limit the relative bending movement between said components permitted by said universal joint.

Claim 33

Apparatus as defined in claim 25 wherein said anti-friction means each comprise a roller rotatably mounted on the free end of its associated arm.

Claim 34

Apparatus as defined in claim 25 including tractor means movable within said pipeline for moving and guiding the interconnected rigid components to predetermined positions within the pipeline, said tractor means including a frame, a plurality of traction elements, mounting means for mounting the traction elements relative to the frame to cause the elements to be urged against the inner walls of the pipeline, means for driving at least one of the traction elements to cause the tractor means to move within the pipeline and means for connecting the sensor unit to the tractor means.