In-pipe inspection robot

Patent metadata

Field	Value
Publication number	US-9982830-B2
Application number	US-201314429602-A
Country	US
Kind code	B2
Filing date	Oct 25, 2013
Priority date	Aug 29, 2013
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

Technical objective is to provide an in-pipe inspection robot for inspecting interior of a pipe, which can exert repulsive force to the pipe when the linear actuator is driven. To this purpose, the in-pipe inspection robot, which is moved inside the pipe to inspect the interior of the pipe, includes a linear actuator which is extendably and contractably driven, and a braking unit configured to fix a rear end of the linear actuator to an inner wall of the pipe and release a front end of the linear actuator from a fixed state, when the linear actuator is being extended, and release the rear end of the linear actuator from the fixed state and fix the front end of the linear actuator to the inner wall of the pipe, when the linear actuator is being contracted.

First claim

What is claimed is:

1. An in-pipe inspection robot which moves inside a pipe, comprising:
a linear actuator which is extendably and contractably driven, and comprising:
a housing part;
a driving motor provided in the housing part;
a screw guide in a cylindrical shape, the screw guide being rotated by the driving motor and having a thread on an upper half of an outer circumference;
a toothed spring wound cylindrically on the screw guide, the toothed spring having a front end being screw-engaged with the thread, and a plurality of teeth on an outer circumference, so as to be exited toward a front direction when the screw guide is rotated; and
a plate spring having a plurality of tooth holes to be meshed with the plurality of teeth, so that the plurality of teeth is meshed with the plurality of tooth holes and exited together while the toothed spring is being exited toward a front direction; and

a braking unit configured to fix a rear end of the linear actuator to an inner wall of the pipe and release a front end of the linear actuator from a fixed state, when the linear actuator is being extended, and release the rear end of the linear actuator from the fixed state and fix the front end of the linear actuator to the inner wall of the pipe, when the linear actuator is being contracted.

2. The in-pipe inspection robot of claim 1 , wherein the braking unit comprises:
a first brake part provided on the front end of the linear actuator; and
a second brake part provided on the rear end of the linear actuator.

3. The in-pipe inspection robot of claim 2 , wherein each of the first and second brake parts comprises:
a braking motor provided on the linear actuator and comprising a motor axis;
a rotating member connected to the motor axis and having such a configuration that a diameter is gradually decreased in a lengthwise direction, the rotating member comprising a thread on an outer circumference; and
a friction part screw-engaged, at one side, to the rotating member, and movably supported, at the other side, by the linear actuator, wherein during driving of the braking motor, the friction part is moved along a lengthwise direction of the rotating member to be gradually extended or contracted according to a shape of the rotating member.

4. The in-pipe inspection robot of claim 3 , wherein the friction part comprises two or more friction members provided at interval with reference to a center of the rotating member.

5. The in-pipe inspection robot of claim 3 , wherein the linear actuator comprises a housing, the braking motor is provided in the housing, and the motor axis is exposed outside the housing to be connected with the rotating member.

6. The in-pipe inspection robot of claim 5 , wherein the friction part is provided in the housing so as to be movable in a first direction and a second direction by a movement guide part, wherein the first direction corresponds to the lengthwise direction of the rotating member and the second direction corresponds to a radial direction of the rotating member, and
the movement guide part comprises:
a horizontal long hole elongated in the housing along the second direction;
a perpendicular through hole elongated in the friction part along the first direction; and
a guide member movably inserted, with one side, into the horizontal long hole and inserted, with the other side, to the perpendicular through hole.

7. The in-pipe inspection robot of claim 5 , wherein each of the first and second brake parts further comprises a roller part rotatably provided on the housing so as to be smoothly moved along the inner wall of the pipe, when the friction part is separated from the inner wall of the pipe.

8. The in-pipe inspection robot of claim 7 , wherein the roller part is provided at a location corresponding to the friction part.

9. The in-pipe inspection robot of claim 1 , wherein the housing part comprises a first housing and a second housing, and when the braking unit comprises a first brake part provided on the front end of the linear actuator and a second brake part provided on the rear end of the linear actuator, the first brake part is provided on the first housing and the second brake part is provide don the second housing.

10. The in-pipe inspection robot of claim 1 , wherein the linear actuator further comprises a guide arm provided on the housing part, to bring the plate spring to a close contact with the toothed spring while the plurality of teeth is being engaged with the plurality of tooth holes.

11. The in-pipe inspection robot of claim 1 , wherein the toothed spring is operated according to forward and reverse direction of the driving motor so that during forward rotation of the driving motor, the toothed spring is exited by the screw guide toward the front direction, thus widening pitch interval thereof, and during reverse rotation of the driving motor, the toothed spring is entered by the screw guide toward the rear direction and stacked into a cylindrical shape, and
the plate spring is operated according to the forward and reverse rotation of the driving motor so that during forward rotation of the driving motor, the plate spring is exited together with the toothed spring which is exiting, as the plurality of tooth holes is meshed with the plurality of teeth of the toothed spring, thus being extended into a cylindrical shape with an increased length, and during reverse rotation of the driving motor, the plate spring is stacked in a radial direction thereof, thus decreasing in the length thereof.

12. The in-pipe inspection robot of claim 11 , wherein the plurality of tooth holes comprise a plurality of upper tooth holes formed in an upper portion of the plate spring, and a plurality of lower tooth holes formed in a lower portion of the plate spring, and
the plurality of lower tooth holes and the plurality of upper tooth holes are overlapped at each pitch and are meshed with the plurality of teeth.

13. The in-pipe inspection robot of claim 1 , wherein the screw guide has a shape of a hollow cylinder, and the driving motor is located inside the screw guide.

Assignees

• Korea Inst Ind Tech

Inventors

• Kwon O-Hung
• Lee Sang-Won
• Won Dae-Hee
• Kim Jin Young

Classifications

• Y10S901/44

  inspection · CPC title

• F16L55/34 Primary

  the pig or mole being moved step by step · CPC title

• F16L2101/30

  Inspecting, measuring or testing · CPC title

• Y10S901/01

  Mobile robot · CPC title

• B25J5/00

  Manipulators mounted on wheels or on carriages (B25J1/00 takes precedence; programme-controlled manipulators B25J9/00 {; vehicle aspects B60, B62, e.g. remote-controlled steering for motor vehicles B62D1/24; control of position of vehicles G05D1/00}) · CPC title