Abstract
An apparatus is provided for bending a pipe and checking a bent shape of the pipe. The apparatus includes a bender for forming a bend in the pipe and at least two cameras for determining an alignment of the pipe in proximity to the free end of the pipe.
Claims
1. An apparatus for bending a pipe and testing a shape of the pipe after bending, comprising: a bender for bending a pipe a specified amount; a criteria pin in proximity to the bender and defining a specified position and alignment for a free end of the pipe after completing a plurality of bends; at least one camera in proximity to the bender and the criteria pin for obtaining at least one image of the pipe and the criteria pin in proximity to the free end of the pipe for determining a position and an alignment of the pipe in proximity to the free end; and a controller connected to the at least one camera, the controller being operative to compare the location of the free end of the pipe to a specified location and to compare the alignment of the free end of the pipe to a specified alignment, wherein the controller is connected to the bender and operates the bender to form specified bends in the pipe.
2. The apparatus of claim 1 wherein the at least one camera comprises at least two cameras disposed for obtaining images of the free end of the pipe and the criteria pin from at least two different angular orientations.
3. The apparatus of claim 2, wherein the two cameras are aligned substantially perpendicular to one another.
4. The apparatus of claim 1 further comprising at least two profile validation channels positionable in proximity to a straight section of the pipe between two adjacent bends in the pipe for determining a position and an alignment of the straight section of the pipe.
5. The apparatus of claim 4, wherein each of the profile validation channels is substantially semi cylindrical, the semi cylindrical profile validation channels having concave sides configured to be positioned in opposed facing relationship radially outward of the pipe.
Description
BRIEF DESCRIPTION OF DRAWINGS
(1) FIG. 1 is a schematic illustration of a pipe bending apparatus in accordance with an embodiment of the invention.
(2) FIG. 2 is a perspective view of straight pipe length checking device.
(3) FIG. 3 is a schematic illustration of a known pipe bender that may be incorporated into the pipe bending apparatus of the invention.
(4) FIG. 4 is a perspective view of an example of a bent pipe that has been bent by the pipe bender of FIG. 3.
(5) FIG. 5 is a perspective view of a profile validation device of the pipe bending apparatus in an open position of the profile validation device
(6) FIG. 6 is a perspective view of the profile validation device of FIG. 5 in the closed position.
(7) FIG. 7 is a perspective view showing the back-check sensors of the profile validation device of FIGS. 5 and 6.
(8) FIG. 8 is a perspective view of a position sensor of an end check apparatus for sensing the position of the free end of the bent pipe.
(9) FIG. 9 is a perspective view of the position sensor of FIG. 8
(10) FIG. 10 is a plan view showing a camera assembly for validating and alignment of a portion of the bent pipe in proximity to the free end.
(11) FIG. 11 is an image of a free end of a bent pipe within tolerance.
(12) FIG. 12 is an image of free end of a bent pipe that is not within tolerance.
DETAILED DESCRIPTION
(13) A highly simplified schematic illustration of a pipe bending apparatus in accordance with the invention is identified generally by the numeral 10 in FIG. 1. The pipe bending apparatus 10 includes a straight pipe storage bin 12 for storing straight pipes that are to be bent by the apparatus 10. The pipe bending apparatus further includes a straight pipe measurement device 16, as shown in greater detail in FIG. 2. The pipe measurement device 16 measures actual lengths of the pipes received from the straight pipe bin 12. Pipes that are determined by the straight pipe measurement device 16 to be too long or too short are transferred to a reject bin 18. Pipes that are determined to have acceptable lengths are transferred to a pipe bender 20, which is illustrated in greater detail in FIG. 3. After the pipes have been bent into a specified shape by the pipe bender 20, pipes 14 that are determined by the profile validation device 22 to be unacceptable are transferred to a reject bin 24. Pipes 14 that are determined by the profile validation device 22 to be acceptable are analyzed further by an end checking apparatus 26. Bent pipes 14 that are determined by the end checking apparatus 26 to have end regions that are properly positioned and aligned are transferred to a receptacle 28 for approved pipes 14. Pipes 14 that are determined by the end checking apparatus 26 to be out of tolerance are transferred to the reject bin 24. The pipe bending apparatus 10 of FIG. 1 further includes a controller 30 that stores data regarding dimensions and shapes for the pipes 14 and that controls the operations of the straight pipe measurement device 16, the pipe bender 20, the profile validation device 22 and the end check apparatus 26.
(14) The straight pipe measurement device 16, as shown in FIG. 2 is operative to position the straight pipes parallel to one another and perpendicular to end plates 17a and 17b. Each pipe is positioned with one end adjacent the end plate 17a. The position of the opposed end of the pipe relative to the end plate 17b then is determined so that the actual length of the pipe can be compared to a specified length. Pipes that do not conform to the specified length are transferred to the reject bin 18 without performing bending work on the dimensionally unacceptable pipes 44.
(15) Straight pipes that are determined to have acceptable lengths are transferred to the pipe bender 20 having an analogous mechanism, as illustrated in FIG. 3. The pipe bender 20 illustrated in FIG. 3 is of prior art design, and conforms to the pipe bender illustrated in U.S. Pat. No. 4,938,050. The pipe bender 20 includes a stationary frame 33 and a bending member 36. The stationary frame 33 is formed by connecting bar stock or pipe stock together into a shape conforming to the finished curved shape of a pipe over its whole length and includes a bending section having a guide surface which has a curvature smaller than the bend radius of the pipe in its lengthwise direction and is orthogonal to a bend plane in its widthwise direction. The bending member 36 has an outer periphery facing the guide surface and is moved from outside the stationary frame 33 toward the stationary frame 33 by an actuator 34 attached to the frame such that the pipe is bent to lie along the guide surface. The straight pipe is secured at its fixed point by the use of a clamping tool and then the bending work is carried out from the secured portion toward a free end by causing the straight or circular movement of the bending member 36 progressively toward the frame such that the pipe is pressed against to lie along the frame in contact therewith. One example of a bent pipe 14 is shown in FIG. 4. The bender 20 can take many other forms. For example, the pipe may be gripped at an intermediate position rather than the end. Rollers of plural radial dimensions can be provided for forming bends of different radii of curvatures.
(16) The bent pipe 14 then is validated by the profile validation device 22, as illustrated in FIGS. 5-7. The profile validation device includes at least one pair of profile validation channels 40, with the profile validation channels 40 in each pair having a concave surface 42 disposed to face the opposing profile validation channel 40 in the respective pair. The profile validation channels 40 can be moved to an open position illustrated in FIG. 5 where the profile validation channels 40 are spaced from one another so that a straight section of the bent pipe 14 can be placed between the profile validation channels 40 in the respective pair. The profile validation channels 40 in each pair also can be moved to a closed position, as illustrated in FIG. 6, where the concave surfaces 42 of the profile validation channels 40 form a continuous cylindrical channel that will surround a straight section of the bent pipe 14. The profile validation device 22 includes sensors that sense contact of the pipe 14 with either of the profile validation channels 40 in the respective pair. A pipe 14 that has been bent properly or that is within a predetermined range of tolerances will not contact either of the profile validation channels 40. On the other hand, a profile validation channel 40 that senses contact with a bent pipe indicates that the bent pipe does not conform to specifications and must be transferred to the reject bin 24 or possibly subjected to corrective bending.
(17) A pipe 14 that does not conform to the bent specifications is likely to contact one or both profile validation channels 40 and can cause one or both profile validation channels 40 to shift from a specified position. Additionally, forces generated by moving the profile validation channels 40 between the open and closed positions can cause shifting of the respective profile validation channels 40. Accordingly, the profile validation device 22 has back-check sensors 46, as shown in FIG. 7. The back-check sensors 46 are operative to sense the positions of the profile validation channels 40 upon the completion of each bend, or upon completion of a selected number of bends or upon completion of a bend where a pipe 14 has contacted a profile validation channel 40. Adjustments to the profile validation channels 40 then can be carried out if necessary.
(18) Those pipes 14 determined by the profile validation device 22 to have an acceptable profile at intermediate positions along the pipe 14 are transferred to pipe end checking apparatus 26. The pipe end checking apparatus 26 includes a criteria pin 50 opposed to a specified position for the extreme free end of the bent pipe 14. The criteria pin 50 provides a datum or frame of reference with respect to both the position and alignment of the free end of the bent pipe 14, as illustrated in FIGS. 8 and 9. The end checking apparatus 26 further includes two cameras 52 and 54 facing toward a predetermined position of a region of the bent pipe 14 in proximity to the free end of the pipe 14, as illustrated in FIG. 10. The cameras 52 and 54 are aligned perpendicular to one another and are operative to produce images of the pipe 14 and the criteria pin 50 in two perpendicular planes. These images then can be compared by the controller 30 to specified positions and alignments of the end region of the bent pipe 14. FIG. 11 provides an example of an image produced by one of the cameras 52 or 54 of a pipe 14 that has a proper alignment and position as compared to a specified alignment and position. FIG. 12 is an example of an image produced by one of the cameras 52 or 54 of a pipe 14 that is not aligned within a specified range of tolerances for the bent pipe 14. Thus, the pipe 14 illustrated in FIG. 12 would be transferred to the reject bin 24 or possibly could be subjected to corrective bending.
