JP2024063260A - Correction device and correction method - Google Patents

Abstract

[Problem] To provide a pipe straightening device and a straightening method. [Solution] The straightening device (1) includes a control unit (13) that controls the position of a straightening mechanism (12) so that a contact roller (22, 42) contacts a predetermined position of a pipe (100) while the pipe is being rotated by a pipe rotation unit (22) and a load of a predetermined magnitude is applied to the predetermined position. [Selected Figure] Figure 3

Description

The present invention relates to a correction device and a correction method for correcting deformations in tubes.

Equipment equipped with various mechanisms is known for straightening bends and oval deformations in pipes such as iron pipes. For example, Patent Document 1 discloses a mechanism that uses a bend inspection device to detect pipes that need straightening, places the detected pipe in the straightening device, and then measures the amount of bend. With this mechanism, the pipe is positioned so that the parts with the largest amount of bend are straightened, and straightening is performed in a fixed state, i.e., without rotating the pipe. This mechanism also repeatedly performs straightening while checking the amount of bend.

Japanese Patent Application Laid-Open No. 11-057859

The technology in Patent Document 1 requires identifying the areas that need to be straightened, which means that equipment is needed to identify the bent pipe and pinpoint the bent areas of the pipe, making the overall straightening equipment larger. In addition, it takes time to identify these areas, which lengthens the straightening time and reduces work efficiency.

Therefore, one aspect of the present invention aims to provide a pipe straightening device and method that improves work efficiency compared to conventional straightening mechanisms.

In order to solve the above problems, a straightening device according to one aspect of the present invention is a straightening device for straightening deformation of a tube, and includes a tube rotation unit that rotates the tube around the tube axis, a straightening mechanism having a contact roller that can contact a predetermined position on the outer circumferential surface of the tube and can rotate in response to the rotation of the tube, and a control unit that controls the movement of the position of the straightening mechanism, and the control unit controls the position of the straightening mechanism so that the contact roller comes into contact with the predetermined position of the tube while it is being rotated by the tube rotation unit, thereby applying a load of a predetermined magnitude to the predetermined position.

According to the above configuration, the position of the contact roller is controlled, and a load is applied to a predetermined position on the outer circumferential surface of the rotating tube by the contact roller. This applies an even load to the tube along its outer circumferential surface, making it possible to straighten the deformed tube over its entire length.

In addition, with the above-mentioned configuration, the deformation is corrected over the entire length of the tube by applying a load to the specified position of the tube with the contact roller, so that inspections to identify the deformed area before the straightening and inspections to determine whether deformation exists or not can be omitted. Therefore, there is no need to install such an inspection mechanism, and the equipment for performing the straightening can be made smaller than before. In addition, the time required for such inspections during the tube straightening process can be omitted, which improves the work efficiency of tube straightening.

Furthermore, in conventional straightening methods, it was necessary to adjust the straightening position of the tube (by rotating the tube) based on the inspection results of the deformed area, but with the above configuration, the tube is straightened while being rotated, eliminating the need for the conventional adjustment work of the tube's straightening position, and significantly reducing work time.

In addition, with the above-mentioned configuration, the structure that contacts the predetermined position is a contact roller that rotates in response to the rotation of the tube, so that the load can be applied without damaging the outer surface of the tube.

In addition, in the straightening device according to one aspect of the present invention, in the above configuration, the control unit has a movement speed adjustment unit that adjusts the speed at which the position of the straightening mechanism is moved.

According to the above configuration, by providing the moving speed adjustment unit, when the contact roller, which is in a position to apply the load of the predetermined magnitude to the predetermined position of the tube, finishes applying the load and leaves the predetermined position of the tube, the load applied to the predetermined position can be slowly reduced. By slowly reducing the load in this way, the residual stresses caused by the deformation of the tube can be continuously cancelled out, leading to zero residual stress, and the tube can be straightened over its entire length. On the other hand, when applying a load to the predetermined position of the tube, it is possible to press the contact roller rapidly, i.e., faster than the moving speed when reducing the load. Therefore, by adjusting the moving speed to an appropriate speed depending on the process, the processing time required for straightening can be minimized.

In addition, in the straightening device according to one aspect of the present invention, in the above configuration, the tube has a receiving port at one tube end and a straight tube section between the receiving port and the other tube end, the straightening mechanism has a first straightening member having a first contact roller as the contact roller, and a second straightening member provided at a different location along the tube axis direction of the tube from the first straightening member and having a second contact roller different from the first contact roller as the contact roller, the first straightening member sets the central portion of the tube in the tube axis direction as the predetermined position and brings the first contact roller into contact with the central portion, and the second straightening member sets the boundary portion between the receiving port and the straight tube section as the predetermined position and brings the second contact roller into contact with the boundary portion.

With this configuration, the second straightening member can effectively apply a load to the boundary portion (sometimes called the neck portion) of a pipe with a receiving port, which has a relatively large amount of bending. Also, in a long pipe, the central portion in the axial direction of the pipe is prone to bending, so the first straightening member can effectively apply a load to the central portion. The first straightening member and the second straightening member can effectively correct deformation of the pipe with a receiving port over the entire length of the pipe.

In order to solve the above problem, a straightening method according to one aspect of the present invention includes a step of rotating a tube around the tube axis, a first step of contacting a straightening mechanism with a predetermined position on the outer circumferential surface of the rotating tube and moving the straightening mechanism in a predetermined direction to apply a load of a predetermined magnitude to the predetermined position, and a second step of gradually reducing the load by moving the straightening mechanism in a direction opposite to the predetermined direction after the first step, and the speed of the movement of the straightening mechanism in the second step is made slower than the speed of the movement of the straightening mechanism in the first step.

According to the above method, the straightening mechanism applies a load to a predetermined position on the outer periphery of the tube rotating around the tube axis, so that the load is applied evenly along the outer periphery of the tube, and the deformed tube can be straightened over its entire length.

According to the above method, by applying a load to the specified position of the tube, deformation is corrected over the entire length of the tube, so inspections to identify the deformed area before straightening and inspections to determine whether deformation exists can be omitted. Therefore, there is no need to install such an inspection mechanism, and the equipment used to perform the straightening can be made smaller than before. In addition, the time required for such inspections during the tube straightening process can be omitted, which improves the work efficiency of tube straightening.

Furthermore, in conventional straightening methods, it was necessary to adjust the straightening position of the tube (by rotating the tube) based on the inspection results of the deformed area, but with the above configuration, the tube is straightened while being rotated, eliminating the need for the conventional adjustment work of the tube's straightening position, and significantly reducing work time.

Furthermore, according to the above method, by specifying the speed of movement of the straightening mechanism as described above, the load applied to the specified position can be slowly reduced. By slowly reducing the load in this manner, the residual stresses associated with the deformation of the tube are continuously cancelled out, leading to zero residual stress, and the tube can be straightened to a straighter shape. On the other hand, in the first step of applying a load to the specified position of the tube, the load is applied rapidly, i.e., faster than the movement speed when the load is reduced. Therefore, by adjusting the movement speed to an appropriate speed for each step, the processing time required for straightening can be minimized.

In a straightening method according to one aspect of the present invention, the pipe has a receiving port at one end and a straight pipe section between the receiving port and the other end, and the first step includes a first step and a second step performed after the first step, in which the boundary portion between the receiving port and the straight pipe section is set as the predetermined position and the straightening mechanism is brought into contact with the boundary portion, and in the second step, the central portion of the pipe in the axial direction is set as the predetermined position and the straightening mechanism is brought into contact with the central portion.

According to the above method, by first applying a load to the boundary portion (sometimes called the neck portion) of a pipe with a receiving port, where the amount of bending is relatively large, the pipe can be effectively straightened. Also, since the central portion of a long pipe in the axial direction is prone to bending, applying a load to the central portion of the pipe, which has already been straightened to a certain extent by the load on the boundary portion, makes it possible to straighten the pipe more effectively.

According to one aspect of the present invention, it is possible to provide a pipe straightening device and method that improves work efficiency compared to conventional straightening mechanisms.

FIG. 1 is a plan view of a tube straightening line including a straightening device according to an embodiment of the present invention. 2 is a side view, partially in cross section, of a tube to be straightened by the straightening device shown in FIG. 1 . FIG. 2 is a side view of the correction device shown in FIG. 1 . FIG. 2 is a partial side view of the correction device shown in FIG. 1 . FIG. 2 is a side view of a pipe rotation unit of the straightening device shown in FIG. 1 as viewed in the pipe axis direction. 5 is a cross-sectional view of the second correcting member 40 taken along the line AA' shown in FIG. 4. 2 is a block diagram showing a configuration of a control unit of the correction device shown in FIG. 1 . FIG. 2 is a diagram of a pipe produced on a pipe production line and before being straightened by a straightening device, showing the pipe in a bent state. FIG. 1 is a diagram illustrating the relationship between the residual stress generated in a bent pipe and the new stress (residual stress) caused by the straightening device, using a cross section perpendicular to the pipe axis. 1 is a flowchart of a correction method according to an embodiment of the present invention. FIG. 13 is a diagram showing a modified example of the orthodontic device according to an embodiment of the present invention.

The correction device and correction method according to one embodiment of the present invention will be described below with reference to the drawings. The drawings also show three-dimensional coordinates of the XYZ system, with the XY plane defining the horizontal plane and the Z axis defining the vertical direction (the negative direction of the Z axis defines the direction of gravity).

Figure 1 is a plan view showing a tube straightening line 2 including a straightening device 1 according to one embodiment of the present invention. The tube straightening line 2 shown in Figure 1 can be incorporated into a part of a tube manufacturing line. The example shown in Figure 1 shows three tubes 100 whose tube axes extend in the X-axis direction being transported sequentially in the positive Y-axis direction through the tube straightening line 2 by a transport device 3. The straightening device 1 is disposed on the positive Y-axis side of the transport device 3. There are no particular limitations on the configuration of the transport device 3, and a well-known configuration can be used.

<Pipes to be corrected>
First, a pipe 100 to be straightened by the straightening device 1 of the present embodiment will be described with reference to Fig. 2. For convenience of explanation, Fig. 2 is a partially cutaway view, and the hatched portion represents the cut surface of the pipe 100.

As shown in FIG. 2, the pipe 100 has a receiving port 100b formed at one end and an insertion port 100c formed at the other end. A straight pipe section 100a is formed between the receiving port 100b and the insertion port 100c, and extends in a substantially straight line. The diameter of the inner circumferential surface of the insertion port 100c is substantially constant along the pipe axis. Since the diameter of the inner circumferential surface of the insertion port 100c is substantially constant along the pipe axis and is the same as the diameter of the inner circumferential surface of the straight pipe section 100a, it can be included as part of the straight pipe section 100a.

The socket 100b has a shape that allows the insertion of the insertion port of another pipe. In addition, an annular groove is formed on the inner peripheral surface of the socket 100b for mounting a lock ring to prevent the pipe 100 from coming loose when it is connected to another pipe. The socket 100b and the insertion port 100c allow the pipe 100 to be connected to another pipe.

An example of a pipe 100 with the above configuration is a well-known ductile iron pipe used as an earthquake-resistant pipe for water supply, etc. However, it is not limited to this. A pipe 100 with such a configuration is manufactured on a pipe manufacturing line, transported to a pipe straightening line 2 installed midway along the manufacturing line, and then transported to the straightening device 1 by a conveying device 3.

Incidentally, the tube 100 ideally has a straight tube axis, but bends (warping) may occur on the tube production line. Also, the cross section of a tube 100 such as a ductile iron pipe is ideally circular, but the circularity may decrease and the tube may become elliptical. In this specification, these bends (warping) and ellipses are collectively referred to as deformations of the tube 100, and a correction device 1 is provided as a device for correcting these deformations.

<Orthodontic Device>
3 is a side view of the correction device 1, showing a state in which a tube 100 is being transported to the correction device 1. The correction device 1 includes a tube rotation unit 11, a correction mechanism 12, and a control unit 13. The configurations of these units will be described below.

(Tube Rotation Section 11)
The pipe rotation unit 11 rotates the pipe 100 around the pipe axis. One example of the pipe rotation unit 11 is a rotating roller. As shown in Fig. 3, the pipe rotation unit 11 rotates the pipe 100 around the pipe axis by rotating a rotation mechanism (rotating roller) in contact with the outer circumferential surface of the pipe 100 while supporting the pipe 100 from below on the receiving port 100b side and the insertion port 100c side of the pipe 100.

Figure 4 is an enlarged view of the area enclosed by the dashed double-dashed line in Figure 3, and Figure 5 is a side view of the tube rotation section 11 shown in Figure 4 as viewed in the X-axis direction.

As shown in FIG. 5, the tube rotation unit 11 includes two rotating rollers 11a and 11b, and a drive unit 11k that drives the two rotating rollers 11a and 11b to rotate. The two rotating rollers 11a and 11b are adjacent to each other with their rotation axes parallel to each other along the X-axis direction, and a tube 100 having a tube axis in the X-axis direction is placed in a valley formed at the boundary between the roller surface of the rotating roller 11a and the roller surface of the rotating roller 11b. The drive unit 11k rotates the two rotating rollers 11a and 11b in the same direction. This allows the tube 100 to rotate around the tube axis.

By using two rotating rollers 11a and 11b to rotate the tube in this way, the two rotating rollers 11a and 11b can be used in common even for tubes with different diameters, making it possible to reduce equipment costs. Figures 4 and 5 also show hypothetical examples of two types of tubes with different diameters.

The rotation speed (unit: rpm) of the tube 100 by the tube rotation unit 11 can be, for example, 20 to 95 rpm, and preferably 60 to 95 rpm. In terms of the time per rotation of the tube 100, it can be 0.6 to 3 seconds/revolution, and preferably 0.6 to 1 second/revolution.

(Correction mechanism 12)
The straightening mechanism 12 includes a first straightening member 20 having a first contact roller 22 (contact roller), and a second straightening member 40 having a second contact roller 42 (contact roller).

The first straightening member 20 and the second straightening member 40 are provided at different positions along the tube axis direction (X-axis direction) of the tube 100. Specifically, the first straightening member 20 is disposed near the central portion 100m (predetermined position) in the tube axis direction of the tube 100 so that the first contact roller 22 contacts the central portion 100m. The position of the first contact roller 22 is not limited to the vicinity of the central portion 100m. The second straightening member 40 is disposed near the boundary portion 100p (FIG. 2) (predetermined position) between the receiving port 100b and the straight tube portion 100a so that the second contact roller 42 contacts the boundary portion 100p. The boundary portion 100p is sometimes referred to as the neck portion.

The first contact roller 22 and the second contact roller 42 can contact a predetermined position on the outer circumferential surface of the tube 100 and can rotate following the rotation of the tube 100 by the tube rotation unit 11. The first contact roller 22 is disposed at the lower end portion of the first straightening member 20, and the second contact roller 42 is disposed at the lower end portion of the second straightening member 40.

Figure 6 is an arrow cross-sectional view of the second straightening member 40 taken along the cutting line A-A' shown in Figure 4, showing the second straightening member 40 cut along the YZ plane at the position of the second contact roller 42. For ease of explanation, Figure 6 also shows the rotating rollers 11a and 11b of the tube rotation unit 11. Note that since the first straightening member 20 and the second straightening member 40 have the same configuration, only the configuration of the second straightening member 40 will be explained here, and the configuration of the first straightening member 20 will not be explained.

The second straightening member 40 includes a second contact roller 42, a roller support part 43, and a straightening drive part 44.

As shown in FIG. 6, two second contact rollers 42 are arranged side by side in the Y direction. Each second contact roller 42 is a driven roller, and rotates about a rotation axis extending in the X-axis direction by abutting the outer circumferential surface of each second contact roller 42 against the tube 100 rotated by the tube rotation unit 11. The two second contact rollers 42 arranged in the Y-axis direction are arranged to clamp the area of the outer circumferential surface of the tube 100 above the tube axis in the Y direction while rotating following the rotation of the tube 100. This supports the tube 100 placed on the tube rotation unit 11 so that it does not shift upward.

The peripheral surface of the second contact roller 42 is made of a material that can withstand the load. A specific example of the material is iron, but it is not limited to this and any material with extremely high hardness can be used (such as hard resin). Furthermore, it is preferable that the peripheral surface shape of the second contact roller 42 is configured in an arc shape so as not to damage the outer peripheral surface of the tube 100 by contacting it.

The roller support part 43 supports the second contact roller 42. The roller support part 43 is connected to the correction drive part 44.

The correction drive unit 44 moves the roller support unit 43 in the positive and negative directions along the Z axis, thereby moving the second contact roller 42 in the positive and negative directions along the Z axis. The correction drive unit 44 moves the roller support unit 43 under the control of the control unit 13.

The first straightening member 20 and the second straightening member 40 each have a contact roller at their lower end, and can be described as a ram that moves the contact roller up and down.

(Control unit 13)
The control unit 13 controls the movement of the position of the straightening mechanism 12, i.e., the positions of the first straightening member 20 and the second straightening member 40. Specifically, the control unit 13 controls the positions of the first straightening member 20 and the second straightening member 40 so that the first contact roller 22 and the second contact roller 42 contact each of the predetermined positions described above of the tube 100 rotated by the tube rotation unit 11, and a load of a predetermined magnitude is applied to each predetermined position. Furthermore, when moving the straightening mechanism 12 (the first contact roller 22 and the second contact roller 42), the control unit 13 controls the moving speed of the movement until the correcting mechanism 12 reaches the predetermined position described above, and the moving speed of the movement for retracting from the predetermined position after applying the load of the predetermined magnitude.

The control unit 13 controls the positions of the first straightening member 20 and the second straightening member 40 independently of each other, but since the control content is the same, the following describes the control of the movement of the position of the first straightening member 20, and the description of the control of the movement of the position of the second straightening member 40 is omitted unless otherwise specified, as it is similar to the control of the movement of the position of the first straightening member 20.

Figure 7 is a block diagram showing the configuration of the control unit 13. The control unit 13 includes a position adjustment unit 131 that controls the position of the first contact roller 22 of the first correction member 20, and a movement speed adjustment unit 132 that adjusts the speed at which the position of the first contact roller 22 moves with respect to the aforementioned movement speed. Note that in this embodiment, the configuration is divided into the position adjustment unit 131 and the movement speed adjustment unit 132, but one aspect of the present invention is not limited to this, and any configuration that realizes the functions described in this embodiment may be used.

The position adjustment unit 131 adjusts the position of the first contact roller 22 to a specified position. The position of the first contact roller 22 may be any of the following positions:
A position above the pipe 100, where the movement of the first contact roller 22 starts toward the central portion 100m (predetermined position) of the pipe 100 (movement start position)
The position where contact with the outer circumferential surface of the central portion 100m (predetermined position) of the pipe 100 begins (contact position).
Position when the load of the above-mentioned predetermined magnitude is applied to the pipe 100 (load position)
A position (release position) where the load is not in contact with the outer circumferential surface of the central portion 100m (predetermined position) of the pipe 100 after the load is applied
- A position above the pipe 100 (retracted position) retracted from near the central part 100m (predetermined position) of the pipe 100.

The position adjustment unit 131 adjusts the first contact roller 22 so that it is positioned in the following order at a predetermined timing: movement start position, contact position, load position, release position, and retracted position.

When the first contact roller 22 is in the loaded position, the position adjustment unit 131 maintains the first contact roller 22 in that position for a predetermined period of time. As an example, the predetermined period of time is at least one rotation of the tube 100.

When the first contact roller 22 is in the load position by the position adjustment unit 131, a load of a predetermined magnitude is applied to the central portion 100m of the pipe 100. As an example, the load is 1.5 to 3 tons.

These predetermined positions may be common to all tubes 100 transported by the transport device 3 from the tube straightening line 2 in order from upstream. However, they may not be common to all tubes 100, and may be determined based on the detection results of detecting the state of each tube 100 using some kind of detection means. One example of using a detection means is to detect whether a predetermined amount of load is applied to the tube 100 by detecting the load of the first straightening member 20, and to determine whether the first straightening member 20 needs to be further pressed, thereby identifying the exact load position.

The moving speed adjustment unit 132 controls the moving speed at which the object moves from a specified position adjusted by the position adjustment unit 131 to another specified position.
Movement speed V1 from the movement start position to the contact position
Movement speed V2 from the contact position to the load position
Movement speed V3 from the load position to the release position
Movement speed V4 from release position to evacuation position
The movement speed adjustment unit 132 adjusts each of the movement speeds V1 to V4.

Specifically, the movement speed adjustment unit 132 determines whether the relationship between the movement speed V2 and the movement speed V3 is as follows:
V2>V3
The control is performed so that

In addition, taking into consideration the efficiency of the correction work performed by the correction device 1, the movement speed adjustment unit 132 sets the movement speed V1 and the movement speed V4 to the fastest among the movement speeds V1 to V4.

In addition, in consideration of the efficiency of the correction work by the correction device 1, the movement speed adjustment unit 132 adjusts the relationship between the movement speed V1 and the movement speed V2 as follows:
V1 ≧ V2
The control is performed so that

In short, the moving speed V3 is set to be slower than the moving speeds V1, V2, and V4. As an example, the moving speed V3 can be set to 5 to 7 mm/sec per rotation of the tube 100, but is not limited to this.

The control unit 13 does not control the position of the first contact roller 22 while three-dimensionally specifying the position with respect to the specified position described above. As an example, the control unit 13 specifies a certain position of the first contact roller 22 in advance (for example, the position of the first contact roller 22 at the movement start position), and measures a specified movement speed and elapsed time from that position, so that the first contact roller 22 is positioned at the specified position described above.

The control unit 13 performs the same process as described above on the second straightening member 40, but the timing of the start of the straightening process of the first straightening member 20 and the timing of the start of the straightening process of the second straightening member 40 are different, as described below. At least one of the moving speeds described above may be different between the first straightening member 20 and the second straightening member 40, but it is preferable that the relationship between the moving speeds V1 to V4 is the same as described above. In FIG. 3, a control unit 13 is provided for each of the first straightening member 20 and the second straightening member 40, but this is not limited to this embodiment, and the first straightening member 20 and the second straightening member 40 may be controlled by one control unit 13. The second contact roller 42 of the second straightening member 40 is configured to apply a load of a predetermined magnitude, for example, 3 to 6 tons, to the boundary portion 100p of the pipe 100.

<Principles of Orthodontics>
The principle of straightening the tube 100 will be described with reference to Figures 8 and 9. Figure 8 is a diagram of the tube 100 in which bending has occurred, which is an example of deformation of the tube 100. When bending has occurred in the center portion of the tube 100 as shown in Figure 8 due to heat treatment or the like during tube manufacturing, residual stress is applied to the tube 100 such that deformation occurs in the direction of the arrow.

In the straightening device 1 of this embodiment, while the tube 100 is rotated by the tube rotating unit 11, the first contact roller 22 is pushed from the outer surface of the tube 100 toward the tube axis by the straightening mechanism 12. At this time, the pushing is performed with a load much stronger than the residual stress shown in FIG. 8. As a result, as shown in FIG. 9, a uniform residual stress is applied along the outer surface of the tube 100. Then, by slowly removing the load, the residual stresses at positions symmetrical with respect to the tube axis cancel each other out and become almost zero, as shown on the right side of FIG. 9. As a result, the tube 100 is straightened over its entire length. Information on the amount of bending of the tube can be obtained from tubes manufactured on a similar manufacturing line in the past, and the pushing amount (distance) is set using this information.

The pipe 100 to be straightened in this embodiment has a receiving port 100b as shown in FIG. 2. In the case of this type of pipe 100, the boundary portion 100p, which is sometimes called the neck portion, has a large amount of curvature, so the inventors have discovered that by pressing the boundary portion 100p with a strong load by the second contact roller 42 of the second straightening member 40, the pipe can be effectively straightened over its entire length.

<Correction method>
The correction method in this embodiment is performed using the above-mentioned correction device 1. Fig. 10 is a process flow of the correction method in this embodiment. The process flow of the correction device can be said to be a control flow by the control unit 13 (Fig. 3).

As described above, the first straightening member 20 and the second straightening member 40 of the straightening mechanism 12 can be controlled independently. However, since it is better to push the boundary portion 100p located on the receiving port 100b side of the pipe 100 first (rather than the central portion 100m), the processing flow of the second straightening member 40 on the receiving port 100b side is prioritized as shown in FIG. 10. Note that the following processing flow is performed while the pipe 100 is rotating around the pipe axis.

Specifically, in step S11, the control unit 13 starts moving the second straightening member 40 on the receiving port 100b side in the negative Z-axis direction (first direction). The timing of starting rotation of the pipe 100 may be before step S11, simultaneously with step S11, or immediately after step S11. The control unit 13 (movement speed adjustment unit 132) lowers the second straightening member 40 at a predetermined movement speed V1.

Next, in step S12, the control unit 13 causes the second contact roller 42 of the second straightening member 40 to contact the boundary portion 100p of the outer circumferential surface of the tube 100, and further moves in the negative Z-axis direction (first direction), thereby pushing the tube 100 and applying a predetermined load to the tube 100. At this time, the control unit 13 (movement speed adjustment unit 132) moves (descends) the second straightening member 40 from the contact position to the load position at a predetermined movement speed V2. As an example, the second contact roller 42 of the second straightening member 40 applies a load of 6 tons to the boundary portion 100p.

Next, in step S13, the control unit 13 maintains the second contact roller 42 of the second straightening member 40 in a state in which a predetermined load is applied to the tube 100 for a predetermined time. This causes the tube 100 to be straightened around the boundary portion 100p.

Next, in step S14, the control unit 13 starts moving (rising) the second straightening member 40 in the positive direction of the Z axis (second direction) to release the load applied by the second contact roller 42 of the second straightening member 40. At this time, the control unit 13 (movement speed adjustment unit 132) moves (rises) the second straightening member 40 at a predetermined movement speed V3 from the load position to a release position where the contact between the tube 100 and the second contact roller 42 is released. The predetermined movement speed V3 is slower than the movement speeds V1, V2, and V4 of the second straightening member 40.

Next, in step S15, the control unit 13 moves the second contact roller 42 of the second straightening member 40 further from the release position to the retracted position. At this time, the control unit 13 (movement speed adjustment unit 132) moves the second straightening member 40 from the release position to the retracted position at a predetermined movement speed V4. The retracted position may be coaxial with the release position in the Z-axis direction, or alternatively, for example, as shown by the dotted line in FIG. 4, the second straightening member 40 may rotate the second contact roller 42 on the distal end side around a central axis along the Y-axis, and the position after rotation may be the retracted position.

The above is the processing flow for the second straightening member 40. Following this processing flow, the processing flow for the first straightening member 20, which applies a load to the central portion 100m of the pipe 100, begins.

The steps of the process flow of the first straightening member 20 are the same as steps S11 to S15 described above. Step S21, in which the control unit 13 starts moving the first straightening member 20 in the negative Z-axis direction (first direction), is performed at the same time as step S12 described above, as an example. However, this is not limited to this.

Next, in step S22, the control unit 13 causes the first contact roller 22 of the first straightening member 20 to contact the central portion 100m of the outer circumferential surface of the tube 100, and then to move in the negative Z-axis direction (first direction), thereby pushing the tube 100 and applying a predetermined load to the tube 100. At this time, the control unit 13 (movement speed adjustment unit 132) moves (descends) the first straightening member 20 from the contact position to the load position at a predetermined movement speed V2. As an example, the first contact roller 22 of the first straightening member 20 applies a load of 3 tons to the central portion 100m.

Next, in step S23, the control unit 13 maintains the first contact roller 22 of the first straightening member 20 in a state in which a predetermined load is applied to the tube 100 for a predetermined time. This causes the tube 100 to be straightened around the central portion 100m.

Next, in step S24, the control unit 13 starts moving (rising) the first straightening member 20 in the positive direction of the Z axis (second direction) to release the load applied by the first contact roller 22 of the first straightening member 20. At this time, the control unit 13 (movement speed adjustment unit 132) moves (rises) the first straightening member 20 at a predetermined movement speed V3 from the load position to a release position where the contact between the tube 100 and the first contact roller 22 is released. The predetermined movement speed V3 is slower than the movement speeds V1, V2, and V4 of the first straightening member 20.

Next, in step S25, the control unit 13 moves the first contact roller 22 of the first straightening member 20 further from the release position to the retracted position. At this time, the control unit 13 (movement speed adjustment unit 132) moves the second straightening member 40 from the release position to the retracted position at a predetermined movement speed V4.

When each of the above steps is completed, the rotation of the tube 100 is stopped, and the series of processes of the straightening method is completed. Note that in FIG. 10, the timing of progression to the next step is synchronized between each step on the second straightening member 40 side and each step on the first straightening member 20 side, but this is not limited to the above.

Thus, the straightening method of this embodiment includes a step (step S0) of rotating the tube around the tube axis, a first step (steps S12, S22) of contacting the first contact roller 22 and the second contact roller 42 of the straightening mechanism 12 with a predetermined position on the outer circumferential surface of the rotating tube 100 and moving the straightening mechanism 12 in a predetermined direction (first direction, Z-axis negative direction) to apply a predetermined load to the boundary portion 100p and the central portion 100m (predetermined position), and a second step (steps S14, S24) of gradually reducing the load by moving the straightening mechanism 12 in the opposite direction (second direction, Z-axis positive direction) to the predetermined direction (first direction, Z-axis negative direction) after the first step, and the speed V3 of the movement of the straightening mechanism 12 in the second step (steps S14, S24) is made slower than the speed V2 of the movement of the straightening mechanism 12 in the first step.

(Effects of this embodiment)
As described above, according to this embodiment, the straightening device 1 is used to straighten the tube 100 as described above, thereby controlling the positions (positions in the Z-axis direction) of the first contact roller 22 and the second contact roller 42, and applying a load to predetermined positions (center portion 100m and boundary portion 100p) on the outer circumferential surface of the rotating tube 100 by the contact rollers. As a result, an even load is applied to the tube 100 along its outer circumferential surface, and the deformed tube 100 can be straightened over its entire length. Note that, in this embodiment, bending is given as an example of deformation, but even if the cross section of the tube 100 is deformed into an ellipse rather than a perfect circle, the straightening device 1 can be used to straighten the tube 100 over its entire length.

In addition, by applying a load to the central portion 100m and boundary portion 100p of the tube using the first contact roller 22 and the second contact roller 42, the deformation of the tube is corrected over the entire length of the tube, so inspections to identify the deformed area before straightening and inspections to determine whether deformation exists can be omitted. Therefore, there is no need to install such an inspection mechanism, and the equipment used to perform the straightening can be made smaller than before. In addition, the time required for such inspections during the tube straightening process can be omitted, improving the work efficiency of tube straightening. It is also possible to add an inspection mechanism that determines whether deformation exists downstream of the straightening device 1.

Furthermore, in conventional straightening methods, it was necessary to adjust the straightening position of the tube (by rotating the tube) based on the inspection results of the deformed area, but with the above-mentioned configuration, the tube is rotated by the tube rotation unit 11 while being straightened, eliminating the need for the conventional adjustment work of the tube straightening position, and significantly reducing the work time.

In addition, with the above-mentioned configuration, the structure that contacts the predetermined position is a contact roller that rotates in response to the rotation of the tube, so that the load can be applied without damaging the outer surface of the tube.

In addition, according to the straightening method of this embodiment, the load applied to the specified position can be slowly reduced by specifying the speed of movement of the straightening mechanism as described above. By slowly reducing the load in this manner, the residual stresses associated with the deformation of the tube are continuously cancelled out, leading to zero residual stress, and the tube can be straightened more straightly over its entire length. On the other hand, in the first step of applying a load to the specified position of the tube, the load is applied rapidly, i.e., faster than the movement speed when the load is reduced. Therefore, by adjusting the movement speed to an appropriate speed depending on the step, the processing time required for straightening can be minimized.

According to the straightening method of this embodiment, the first step (steps S12 and S22) described above includes a previous step (step S12) and a subsequent step (step S22) that is performed after the previous step (step S12). In the previous step (step S12), the boundary portion 100p between the receiving port 100b and the straight pipe portion 100a is set as a predetermined position, and the straightening mechanism is brought into contact with the boundary portion 100p. In the subsequent step (step S22), the central portion 100m in the axial direction of the pipe 100 is set as a predetermined position, and the straightening mechanism 12 is brought into contact with the central portion 100m. This allows the pipe to be effectively straightened by first applying a load to the boundary portion 100p, which has a relatively large amount of bending in a pipe having a receiving port. In addition, in a long pipe, the central portion 100m in the pipe axial direction is prone to bending, so by applying a load to the central portion 100m of the pipe, which has already been straightened to a certain extent by the load on the boundary portion 100p, it is possible to straighten the pipe 100 more effectively.

<Modification>
In the above embodiment, the tube 100 is placed on the tube rotation unit 11, and the straightening mechanism 12 descends from above the tube 100 to bring the first and second contact rollers 22, 42 into contact with the outer circumferential surface of the tube 100, and then the straightening mechanism 12 moves further downward to press the tube 100 downward. However, in one aspect of the present invention, the direction of the tube axis of the tube is not limited to the horizontal direction as shown in Fig. 1, and the movement direction of the straightening mechanism 12 is not limited to the Z-axis direction.

One modified example is shown in FIG. 11. FIG. 11 shows an embodiment equipped with a tube rotation unit 11 that supports the outer peripheral surface of the tube 100 from all four sides with the tube axis parallel to the X-axis. The tube rotation unit 11 is equipped with four rotating rollers 11a, 11b, 11c, and 11d so that the tube 100 can be supported from the top, bottom, left, and right directions. Since the tube 100 is supported by being sandwiched between the tube 100 from all four sides, the tube 100 can be straightened out of its bend no matter what direction the straightening mechanism (shown in FIG. 11 as the first contact roller 22) applies a load to the tube 100 in. In the modified example shown in FIG. 11, the first contact roller 22 applies a load to the tube 100 in the positive direction of the Z-axis. Even in this modified example, the deformation of the tube 100 is straightened over its entire length.

The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the claims.

1 Straightening device 2 Tube straightening line 3 Conveyor device 11 Tube rotating unit 11a, 11b, 11c, 11d Rotating roller 11k Drive unit 12 Straightening mechanism 13 Control unit 20 First straightening member (straightening mechanism)
22 First contact roller (contact roller)
40 Second straightening member (straightening mechanism)
42 Second contact roller (contact roller)
43 Roller support portion 44 Straightening drive portion 100a Straight pipe portion 100b Socket 100c Insertion port (other pipe end)
100m central portion 100p boundary portion 131 position adjustment portion 132 movement speed adjustment portion

Claims (5)

A straightening device for straightening deformation of a tube,
a tube rotation unit that rotates the tube around a tube axis;
a straightening mechanism including a contact roller capable of contacting a predetermined position on an outer circumferential surface of the tube and rotating in response to the rotation of the tube;
A control unit that controls the movement of the position of the correction mechanism;
Equipped with
The control unit controls a position of the straightening mechanism so that the contact roller contacts the predetermined position of the tube while the tube is being rotated by the tube rotation unit, and a load of a predetermined magnitude is applied to the predetermined position.
An orthodontic device characterized by: The control unit has a movement speed adjustment unit that adjusts the speed at which the position of the correction mechanism is moved.
The orthodontic device according to claim 1 . The pipe has a socket at one end and a straight pipe section between the socket and the other end,
the straightening mechanism includes a first straightening member having a first contact roller as the contact roller, and a second straightening member provided at a different location along the tube axis direction of the tube from the first straightening member and having a second contact roller different from the first contact roller as the contact roller,
The first straightening member has a central portion in an axial direction of the pipe as the predetermined position, and brings the first contact roller into contact with the central portion,
the second correcting member sets a boundary portion between the receiving port and the straight pipe portion as the predetermined position and brings the second contact roller into contact with the boundary portion.
The orthodontic device according to claim 1 or 2. rotating the tube about a tube axis;
a first step of contacting a straightening mechanism with a predetermined position on an outer circumferential surface of the rotating tube and moving the straightening mechanism in a predetermined direction to apply a load of a predetermined magnitude to the predetermined position;
a second step of gradually reducing the load by moving the straightening mechanism in a direction opposite to the predetermined direction after the first step;
Including,
The speed of the movement of the straightening mechanism in the second step is made slower than the speed of the movement of the straightening mechanism in the first step.
A correction method characterized by the above. The pipe has a socket at one end and a straight pipe section between the socket and the other end,
The first step includes a first stage step and a second stage step that is performed after the first stage step,
In the previous step, a boundary portion between the receiving port and the straight pipe portion is set as the predetermined position, and the correction mechanism is brought into contact with the boundary portion;
In the latter step, a central portion of the pipe in an axial direction is set as the predetermined position, and the correction mechanism is brought into contact with the central portion.
The method according to claim 4 .

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