Automatic tube expansion device and automatic tube expansion method

Abstract

To provide an automatic tube expansion device and an automatic tube expansion method that can improve the efficiency of a tube expansion work by using a general robot.SOLUTION: An automatic tube expansion device 1 includes a tube expansion device 3 and a robot 2. The tube expansion device 3 includes an expander 4, a rotary drive machine 6, a clamp device 7, a clamp movement device 8, and a feeder 5. The expander 4 has a mandrel 41, a collar front wheel 453, a cylindrical frame 44, and a plurality of rollers 43. The collar front wheel 453 is supported in a freely slidable manner on the mandrel 41. The cylindrical frame 44 is rotatably supported inside the collar front wheel 453. The rotary drive machine 6 rotates the mandrel 41. The clamp device 7 clamps the collar front wheel 453. The clamp movement device 8 moves the clamp device 7 in the axial direction of the expander 4. The feeder 5 moves the mandrel 41 in the axial direction of the expander 4.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an automatic tube expanding device and an automatic tube expanding method. [Background technology]

[0002] An automatic tube expansion device has been proposed that includes an expander having a mandrel and a frame member, a rotary drive that rotates the mandrel, a clamping device that clamps the frame member, and a moving device that moves the clamping device in the axial direction of the expander, and a robot that supports and moves the tube expansion device (Patent Publication No. 2020-138213, hereinafter referred to as Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0003] The mandrel, onto which the frame member is fitted, moves (self-propels) toward the tip end while rotating due to the feed angle action of a roller rotatably held by the frame member. The robot described in Patent Document 1 has a function (hereinafter referred to as a "following function") to make the support position of the tube expanding device by the robot follow the axial movement of the expander by operating the robot to move the expander in the direction of the axial external force while the expander is subjected to an axial external force. However, robots generally do not have a following function. In order to implement Patent Document 1, it is necessary to add a following function to the robot.

[0004] An object of the present invention is to provide an automatic pipe expanding device and an automatic pipe expanding method that can efficiently perform pipe expanding work using a general robot. [Means for solving the problem]

[0005] Book The first aspect of the invention is: Robots and Moves while being supported by the robot, Tube expansion equipment for expanding tubes In place There was, A mandrel, a collar member slidably supported on the mandrel; a cylindrical frame rotatably supported inside the collar member; a plurality of rollers rotatably held by the frame; an expander having a rotary drive that rotates the mandrel; a clamping device for clamping the collar member; a clamp moving device that moves the clamp device in the axial direction of the expander; A feeder that moves the mandrel in the axial direction of the expander And, a base plate having a support portion and fixed to the robot; a feed cylinder that generates a driving force by compressed air; a piston slidably disposed within the feed cylinder; a piston rod having a base end fixed to the piston and a tip end extending from the feed cylinder and connected to the support portion; a feeder having a tube expanding device having Equipped with It is an automatic tube expansion device.

[0006] A second aspect of the present invention is a clamp moving device that moves a frame member having a frame on which a roller is rotatably held toward a front end side of the mandrel relative to the mandrel on which the frame member is fitted; a clamping device clamping the frame member; a robot inserting the frame member and the mandrel into a tube; When the frame member and the mandrel reach a predetermined position, the robot stops. Stop, a feeding device feeding the mandrel, which is rotated in one direction by a rotary drive device, to a tip end side; The frame rotates in the one direction to self-propel the mandrel in a distal direction; The roller expands the tube, When the load torque of the rotary drive machine reaches a predetermined set torque, the rotary drive machine temporarily stops the rotation of the mandrel, The rotary driver rotates the mandrel in the other direction, which is the opposite direction to the one direction, and the frame rotates in the other direction, causing the mandrel to self-retract in the base end direction; the feeding device pulls the mandrel rotating in the other direction back toward the base end, The robot pulls the frame member and the mandrel out of the tube. An automatic tube expansion method, comprising: When the mandrel rotates in the one direction and self-propels toward the distal end, and when the mandrel rotates in the other direction and self-retreats toward the proximal end, and when the mandrel is subjected to an axial external force, the feeding device moves the mandrel in the direction of the axial external force, so that the position of the mandrel follows the axial movement of the mandrel. This is an automatic pipe expansion method. [Effects of the Invention]

[0007] According to the present invention, an automatic pipe expanding device and an automatic pipe expanding method can be provided that can efficiently perform pipe expanding work by using a general robot. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic perspective view of an automatic tube expanding device according to an embodiment of the present invention. [Figure 2] 2 is a schematic block diagram showing the control configuration of the automatic tube expanding device according to the present embodiment together with a cross-sectional view of the expander. FIG. [Figure 3] FIG. 10 is a diagram illustrating the inclination of a roller. [Figure 4] 10 is a flowchart showing the contents of an automatic tube expansion method. [Figure 5] 4 is a schematic side view for explaining the operation of the automatic tube expanding device during tube expanding work. FIG. [Figure 6] 6 is a schematic side view illustrating the operation of the automatic pipe expanding device during pipe expanding work, continuing from FIG. 5. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, in each figure, common components are given the same reference numerals, and redundant explanations thereof will be omitted as appropriate.

[0010] An automatic tube expanding device 1 according to one embodiment of the present invention will be described in detail with reference to FIGS. 1 to 6 as needed.

[0011] As shown in FIGS. 1 and 2, the automatic tube expanding device 1 of this embodiment includes a tube expanding device 3, a robot 2, and a control device 10.

[0012] The tube expanding device 3 performs tube expanding processing on the tube T (see Figure 5(a) etc., the same applies below). The tube expanding device 3 joins the tube T constituting the heat exchanger to the tube plate TB (see Figure 5(a) etc., the same applies below) to which the tube T is attached by expanding the outer diameter of the tube T with an expander 4 and pressing and fixing it to the inner surface of a mounting hole TBa (see Figure 5(a) etc., the same applies below) formed in the tube plate TB. The robot 2 is, for example, a vertical articulated robot, a horizontal articulated robot, an orthogonal axis robot, or a parallel link robot. The robot 2 supports and moves the tube expanding device 3. The tube expanding device 3 is fixed to the tip of the arm 21 of the robot 2. The control device 10 is a computer that controls the operation of each part of the automatic tube expanding device 1 by having the CPU execute a program pre-stored in a storage means.

[0013] The tube expanding device 3 has an expander 4 , a rotary drive machine 6 , a clamping device 7 , a clamp moving device 8 , a feeding device 5 , and a coupling 9 .

[0014] The expander 4 has a mandrel 41, a cylindrical frame member 42, and a plurality of rollers 43. A tapered portion 411 having a smaller diameter at the tip end is formed on the outer circumferential surface of the mandrel 41. The frame member 42 is fitted onto the mandrel 41 so as to be slidable and rotatable. The plurality of rollers 43 are rotatably held by the frame member 42.

[0015] The mandrel 41 has a tapered portion 411 located at the tip end (hereinafter also referred to as the "front side") of the mandrel 41, and a cylindrical portion 412 located at the base end (hereinafter also referred to as the "rear side") of the tapered portion 411. A cap nut 413 is fixed to the tip end of the mandrel 41 by screw fastening. A square shank (not shown) is provided at the rear end of the mandrel 41. The square shank of the mandrel 41 is connected to the rotary shaft 61 of the rotary drive machine 6 via a coupling 9.

[0016] The frame member 42 has a cylindrical frame 44 that rotatably holds the roller 43, and an annular collar 45 attached to the outer peripheral surface of the frame 44. The collar 45 has a collar rear wheel 451 fixed to the outer peripheral surface of the frame 44, and a collar front wheel (collar member) 453 that is rotatably arranged via a ball retainer 452 in front of the collar rear wheel 451 (toward the tip end of the expander 4). In other words, the collar front wheel 453 is slidably supported on the mandrel 41, and the frame 44 is rotatably supported inside the collar front wheel 453.

[0017] The inner diameter of the hollow portion of the frame 44 is slightly larger than the outer diameter of the columnar portion 412 of the mandrel 41. The mandrel 41 is inserted through the hollow portion of the cylindrical frame 44. A plurality of roller grooves 421, which are long grooves, are formed at the tip end of the frame 44, spaced evenly in the circumferential direction, for example, at intervals of 120 degrees. Each roller groove 421 is positioned at the same position in the longitudinal direction of the frame 44. A frusto-conical roller 43 is engaged and held in the roller groove 421. A portion of the roller 43 is exposed from the roller groove 421 to the outer and inner radial directions of the frame 44.

[0018] The rear end of frame 44 has a smaller outer diameter and is formed with a male thread on its outer circumferential surface, onto which a collar rear wheel 451, which is formed with a female thread on its inner circumferential surface, is screwed. Collar rear wheel 451 is fixed to frame 44 with a locking nut 454. Collar rear wheel 451 can be fixed to frame 44 using a method other than the method using locking nut 454, for example, a method using a hexagon socket head set screw. With ball retainer 452 disposed in front of collar rear wheel 451 and collar front wheel 453 disposed in front of ball retainer 452, these are integrated in the axial direction by a retaining ring 455 to form collar 45.

[0019] The roller 43, located radially inside the frame 44, rotates around its longitudinal central axis and contacts with the outer circumferential surface of the tapered portion 411 of the mandrel 41 with its side. On the other hand, the roller 43, located radially outside the frame 44, rotates around its longitudinal central axis and contacts with the inner circumferential surface of the tube T being expanded during the tube expansion process with its side substantially opposite to the contact portion with the mandrel 41.

[0020] 3, roller 43 is disposed with its central axis inclined at a predetermined angle θ with respect to the axial direction of frame member 42 (the same as the axial direction of mandrel 41). Roller 43 is frustum-shaped with a taper that is in the opposite direction to the taper of tapered portion 411 of mandrel 41 and is half the inclination.

[0021] As shown in Figure 2, the rear end of the cap nut 413 is formed with a tapered surface 416 that has a smaller diameter at the rear. With this configuration, when the frame member 42 is moved forward to minimize the tool diameter, the front end of the frame 44 abuts against the tapered surface 416. This causes the central axis of the frame member 42 and the central axis of the mandrel 41 to be centered so that they coincide with each other. This prevents the tip of the mandrel 41 from sagging due to its own weight, improving the ease of insertion of the expander 4 into the tube T. Here, the tool diameter refers to the processing diameter of the tube expansion process using the expander 4, and is the diameter of a circumscribed circle formed by an envelope circumscribing the multiple rollers 43.

[0022] The rotary drive machine 6 rotates the mandrel 41 of the expander 4 via a coupling 9. As the rotary drive machine 6, a servo motor is used here.

[0023] The clamping device 7 clamps the frame member 42 of the expander 4, specifically the collar front wheel 453 (see FIG. 2) of the frame member 42. The clamping device 7 has a pair of claws 71, an air chuck 72, and a support plate 73 that supports the air chuck 72. The pair of claws 71 clamp the frame member 42 of the expander 4 by sandwiching it from both radial sides. The air chuck 72 includes an air cylinder. The air chuck 72 uses air pressure to move the pair of claws 71 back and forth relative to the frame member 42 of the expander 4. The air chuck 72 is fixed to the front surface of the support plate 73. The support plate 73 is rectangular (see FIG. 1).

[0024] As shown in FIG. 2, the claw 71 has a claw main body 711 and a claw support portion 712 that supports the claw main body 711. The claw 71 has an L-shaped cross section. The claw main body 711 has an arcuate surface 713 that contacts the outer peripheral surface of the collar front wheel 453 of the frame member 42. The claw support portion 712 has a passing portion 714 and an abutting portion 715. The passing portion 714 is disposed on the rear side of the claw support portion 712. The passing portion 714 has an arcuate surface with an inner diameter smaller than the outer diameter of the collar front wheel 453. The passing portion 714 allows the collar rear wheel 451 and the locking nut 454 to pass through. The abutting portion 715 is disposed on the front surface of the claw support portion 712. The abutting portion 715 abuts against the collar front wheel 453 of the frame member 42 in the axial direction of the expander 4.

[0025] The clamp moving device 8 moves the clamp device 7 in the axial direction of the expander 4. The clamp moving device 8 is fixed to the casing 62 of the rotary driver 6. An air cylinder is used as the clamp moving device 8 here, but an electric cylinder, for example, may also be used.

[0026] The clamp moving device 8 has a cylinder body 81, a piston 821, and a piston rod 822. The cylinder body 81 generates a driving force by compressed air supplied into the cylinder body 81. The piston 821 is slidably disposed within the cylinder body 81. The base end of the piston rod 822 is fixed to the piston 821, and the tip end extends and protrudes outside the cylinder body 81. A first chamber 811 and a second chamber 812 are formed within the cylinder body 81, with the piston 821 sandwiched between them. The first chamber 811 and the second chamber 812 are connected to the compressed air source 31 via a throttle 35 and a flow path switching valve 33, respectively. The flow rate of the compressed air is adjusted by the throttle 35. The flow path switching valve 33 switches the supply destination of the compressed air.

[0027] When compressed air is supplied to the first chamber 811, the piston rod 822 advances, and when compressed air is supplied to the second chamber 812, the piston rod 822 retreats. The tip of the piston rod 822 is connected to the clamp device 7. Specifically, the tip of the piston rod 822 is fixed to a support plate 73 of the clamp device 7. A guide rod 83 may also be disposed on the support plate 73. The guide rod 83 is slidably inserted into a guide bush 84 provided in the clamp moving device 8. This allows the clamp moving device 8 to move the clamp device 7 smoothly.

[0028] Furthermore, the position sensor 85 is disposed in the cylinder body 81. The position sensor 85 detects the position of the piston 821. The position sensor 85 is, for example, a linear scale.

[0029] The feeder 5 moves the mandrel 41 of the expander 4 in the axial direction of the expander 4. In this embodiment, the feeder 5 is disposed between the tip of the arm 21 of the robot 2 and the rotary driver 6, and moves the mandrel 41 together with the rotary driver 6 and the coupling 9.

[0030] The feed device 5 includes a feed cylinder 51, a piston 521, a piston rod 522, a linear guide 53, and a base plate 54. The feed cylinder 51 generates a driving force by compressed air supplied into the feed cylinder 51. The feed cylinder 51 is connected to a casing 62 of the rotary drive machine 6. The piston 521 is slidably disposed within the feed cylinder 51. The base end of the piston rod 522 is fixed to the piston 521. The tip of the piston rod 522 extends and projects from the feed cylinder 51. A first chamber 511 and a second chamber 512 are formed within the feed cylinder 51, with the piston 521 sandwiched therebetween. The first chamber 511 and the second chamber 512 are connected to the compressed air source 31 via a throttle 34 and a flow path switching valve 32, respectively. The flow rate of the compressed air is adjusted by the throttle 34. The flow path switching valve 32 switches the supply destination of the compressed air.

[0031] The base plate 54 has a support portion 55. The base plate 54 is fixed to the tip of the arm 21 of the robot 2. The linear guide 53 is disposed on the base plate 54 and extends along the axial direction of the expander 4. The feed cylinder 51 is disposed on the linear guide 53. The feed cylinder 51 is guided by the linear guide 53 and reciprocates relative to the base plate 54. The tip of the piston rod 522 is connected to the support portion 55 provided on the end of the base plate 54.

[0032] When compressed air is supplied to the first chamber 511, the piston rod 522 extends, causing the feed cylinder 51 to move forward. As the feed cylinder 51 moves forward, the mandrel 41 moves forward together with the rotary driver 6 and the coupling 9. On the other hand, when compressed air is supplied to the second chamber 512, the piston rod 522 retreats, causing the feed cylinder 51 to move rearward. As the feed cylinder 51 moves rearward, the mandrel 41 moves rearward together with the rotary driver 6 and the coupling 9.

[0033] The control device 10 is connected to a position sensor 85, and receives a signal from the position sensor 85. The control device 10 is also connected to the rotary driver 6 and the flow path switching valves 32 and 33, and controls the operations of these devices.

[0034] Next, a description will be given of the operation of the automatic tube expanding device 1 of this embodiment. The operation of the automatic tube expanding device 1 is controlled by the control device 10. An automatic pipe expanding method for performing pipe expanding work using the automatic pipe expanding device 1 will be described with reference to FIGS.

[0035] First, the robot 2 moves the expander 4 of the tube expansion device 3 to a position facing the end face of the tube T to be expanded. The position of the tube T to be expanded can be identified by importing position data (design data) of the mounting hole TBa in the tube sheet TB or by importing and processing an image of the mounting hole TBa in the tube sheet TB.

[0036] 4, the clamp device 7 unclamps the frame member 42 (S1). Subsequently, the rotary drive machine 6 starts rotating (forward rotation) (S2). Note that the timing at which the rotary drive machine 6 starts rotating can be changed as appropriate, as long as it is before step S5, which will be described later.

[0037] Next, the clamp moving device 8 moves the clamp device 7 toward the axial tip. At this time, the clamp moving device 8 moves (advances) the frame member 42 toward the tip of the mandrel 41 with the abutment portion 715 of the clamp device 7 abutting against the collar front wheel 453 of the frame member 42 (S3). Therefore, the rollers 43 are positioned on the small diameter side of the tapered portion 411 of the mandrel 41, and the amount of radial outward protrusion of the rollers 43 is minimized. In other words, the tool diameter is minimized.

[0038] Next, the clamp device 7 clamps the collar front wheel 453 of the frame member 42 (S4, see FIG. 5(a)). Then, the holding force of the clamp moving device 8 on the axial position of the clamp device 7 is released. Specifically, the clamp moving device 8 enters a brake-released state, that is, a floating state in which it moves in response to an external force.

[0039] Next, the robot 2 inserts the expander 4 of the tube expanding device 3 into the tube T (S6).

[0040] Next, it is determined whether or not the front end surface of the collar front wheel 453 of the frame member 42 has come into contact with the end surface of the tube T, i.e., whether or not it has been detected that the collar front wheel 453 has hit the tube T (S6). Here, the position sensor 85 monitors the position of the piston 821. When the collar front wheel 453 hits the tube T while the robot 2 is moving the tube expanding device 3 forward, the position of the piston 821 is pushed back relative to the cylinder body 81. When the position sensor 85 detects that the piston 821 has been pushed back, the control device 10 determines that the collar front wheel 453 has hit the tube T. It is also possible to detect that the frame member 42 and the mandrel 41 have reached a pre-programmed predetermined position.

[0041] If it is not detected that the color front wheel 453 has hit the tube T (No in S6), the robot 2 continues inserting the expander 4 into the tube T. On the other hand, if it is detected that the collar front wheel 453 has hit the tube T (Yes in S6, see FIG. 5(b)), the robot 2 stops (S7). That is, the position of the tip of the arm 21 of the robot 2 is maintained. That is, with the servo on, the robot 2 maintains the position of the base plate 54 against external forces.

[0042] Simultaneously with or immediately after the robot 2 stops, the feed device 5 operates to advance the feed cylinder 51 (S8, see FIG. 5(c)). As the feed cylinder 51 advances, the mandrel 41 advances together with the rotary driver 6 and the coupling 9. This performs the tube expansion process.

[0043] During the tube expansion process, the front collar wheel 453 of the collar 45 contacts the end surface of the tube T and does not rotate or move in the axial direction. However, because the mandrel 41 is rotationally driven, the rotation of the mandrel 41 causes the roller 43 to rotate on its own axis on the inner surface of the tube T while revolving together with the frame 44. The roller 43 does not move in the axial direction. The frame 44 revolves around its own central axis in accordance with the rotation of the roller 43. The frame 44 does not move in the axial direction. On the other hand, because a feed angle is provided in which the central axis of the mandrel 41 and the central axis of the roller 43 are inclined by a predetermined angle θ, when the mandrel 41 is rotated, it naturally acts to feed in the axial direction. Therefore, while rotating, the mandrel 41 moves toward the tip side due to the action of the feed angle of the roller 43. In other words, the mandrel 41 propels itself. This forward movement of the mandrel 41 moves the contact position between the roller 43 and the mandrel 41 toward the larger diameter side of the tapered portion 411. Then, the tool diameter (the diameter of the contact surface between the roller 43 and the tube T) increases, and the tube T undergoes a tube expansion process.

[0044] While the mandrel 41 is subjected to an external axial force that causes it to self-propel, the compressed air source 31 sends compressed air to the first chamber 511. The air in the second chamber 512 is then exhausted. The feeder 5 then advances the expander 4. That is, the feeder 5 moves the mandrel 41 in the direction of the external axial force. Because air is a compressible fluid, the position of the mandrel 41 follows the axial movement of the mandrel 41 due to its self-propulsion.

[0045] In this way, the mandrel 41 of the expander 4 is subjected to an axial external force in a direction that moves it forward (self-propelling) during the tube expansion process, and is also subjected to an axial external force in a direction that moves it back (self-retreating) when the tube is extracted after expansion. To prevent this axial external force and the power of the feeding device 5 from pressing against each other, the feeding device 5 is driven by compressed air with a relatively low pressure so as to follow the load that is the axial external force.

[0046] Next, the control device 10 determines whether the load torque of the rotary driver 6 has reached a predetermined set torque (S9). The load torque is obtained based on the value of the current flowing through the rotary driver 6.

[0047] If the load torque of the rotary driver 6 has not reached the set torque (No in S9), the tube expanding process continues. On the other hand, when the load torque of the rotary driving machine 6 reaches the set torque (Yes in S9), the rotary driving machine 6 stops rotating and rotates in the reverse direction (S10).

[0048] Simultaneously with the reverse rotation of the rotary driver 6, the feed device 5 operates to retract the feed cylinder 51 (S11). Here, as the feed cylinder 51 retracts, the mandrel 41 retracts together with the rotary driver 6 and the coupling 9. In other words, the feed device 5 pulls the reverse-rotating mandrel 41 back toward the base end. While rotating in the reverse direction, the mandrel 41 moves toward the base end due to the action of the feed angle of the rollers 43, that is, it retracts by itself. This backward movement of the mandrel 41 moves the contact position of the rollers 43 with the mandrel 41 toward the smaller diameter side of the tapered portion 411, thereby reducing the tool diameter.

[0049] While the mandrel 41 is subjected to an external axial force that causes it to self-retract, the compressed air source 31 sends compressed air to the second chamber 512. The air in the first chamber 511 is then exhausted. The feeding device 5 retracts the mandrel 41. That is, the feeding device 5 moves the mandrel 41 in the direction of the external axial force. As a result, the position of the mandrel 41 follows the axial movement caused by the self-retraction of the mandrel 41. The feeding device 5 retracts the mandrel 41 to the retraction end.

[0050] In step S8 or step S11, the driving air may be exhausted from the feed device 5. Specifically, the first chamber 511 and the second chamber 512 are opened to the atmosphere. In this case, the piston 521 moves freely due to an external force, and therefore the piston 52 moves forward or backward in accordance with the self-propulsion or self-retraction of the mandrel 41.

[0051] Next, the robot 2 removes the expander 4 of the tube expanding device 3 from the tube T (S12, see FIG. 6(b)), and the rotary driver 6 stops rotating.

[0052] As described above, the automatic tube expanding apparatus 1 according to this embodiment includes the tube expanding device 3 that expands the tube T, and the robot 2 that supports and moves the tube expanding device 3. The tube expanding device 3 includes the expander 4, a rotary drive machine 6, a clamping device 7, a clamp moving device 8, and a feed device 5. The expander 4 has a mandrel 41, a collar front wheel (collar member) 453, a cylindrical frame 44, and a plurality of rollers 43. The collar front wheel 453 is slidably supported on the mandrel 41. The cylindrical frame 44 is rotatably supported inside the collar front wheel 453. The plurality of rollers 43 are rotatably held on the frame 44. The rotary drive machine 6 rotates the mandrel 41. The clamping device 7 clamps the collar front wheel 453. The clamp moving device 8 moves the clamping device 7 in the axial direction of the expander 4. The feeder 5 moves the mandrel 41 in the axial direction of the expander 4 .

[0053] In this configuration, the clamp moving device 8 moves the frame member 42 toward the tip end of the mandrel 41 via the clamp device 7. As a result, the roller 43 held by the frame member 42 moves toward the smaller diameter side of the tapered portion 411 of the mandrel 41. This allows the clamp moving device 8 to reduce the tool diameter of the expander 4. This allows the robot 2 to easily insert the expander 4 into the tube T. This allows the tube expanding device 3 to automatically expand multiple tubes T in succession, improving the efficiency of the tube expansion work. During the tube expanding process, an external axial force is applied to the mandrel 41 in the direction of self-propulsion. To prevent this external axial force and the power of the feeder 5 from pressing against each other, the feeder 5 is driven by compressed air to follow the load, which is the external axial force. Therefore, the robot 2 does not need to operate in accordance with the external force. Therefore, according to this embodiment, it is possible to provide an automatic tube expanding device 1 that can improve the efficiency of the tube expanding work by using a general robot.

[0054] Furthermore, in this embodiment, the rear collar wheel 451 is fixed to the outer peripheral surface of the frame 44, and the front collar wheel 453 is rotatably arranged relative to the rear collar wheel 451 via a ball retainer 452 on the tip side of the expander 4. With this configuration, it is easy to realize a configuration in which the frame 44 is rotatably supported inside the front collar wheel 453. In this case, when the mandrel 41 self-propels during the tube expansion process, the front collar wheel 453 clamped by the clamp device 7 is pressed against the end face of the tube T to be expanded. Therefore, the tube T to be expanded can be prevented from rotating together with the rotation of the rollers 43 during the tube expansion process.

[0055] This embodiment also includes a control device 10 that causes the position of the mandrel 41 to follow the axial movement of the mandrel 41 while the mandrel 41 is subjected to an axial external force. The control device 10 operates the feed device 5 to move the mandrel 41 in the direction of the axial external force, thereby causing the advancement and retreat of the expander 4 to follow its self-propulsion or self-retraction. In this configuration, the feed device 5 automatically follows the position of the mandrel 41 in accordance with the speed at which the expander 4 self-propels or self-retracts due to the action of the feed angle of the rollers 43. This makes it possible to avoid applying unnecessary force to the tube T, which is the target of tube expansion. This improves the quality of the tube expansion work.

[0056] Furthermore, in this embodiment, the control device 10 controls the axial position of the clamp device 7 to release the holding force applied by the clamp moving device 8. The control to release the holding force is performed when the clamp device 7, together with the frame member 42, is moved by the clamp moving device 8 toward the tip end of the mandrel 41 (S3) and the frame member 42 is clamped by the clamp device 7 (S4). In this configuration, the clamp moving device 8 is in a floating state, moving in response to an external force. As a result, during the tube expansion process, the expander 4 can be maintained pressed against the end face of the tube T as the mandrel 41 rotates and advances within the tube T due to the action of the feed angle of the rollers 43.

[0057] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present invention, and all technical matters included in the technical ideas described in the claims are subject to the present invention. The above-described embodiments are preferred examples, but a person skilled in the art can realize various alternatives, modifications, variations, or improvements from the contents disclosed in this specification, and these are included in the technical scope described in the appended claims.

[0058] For example, in the above-described embodiment, the feed device 5 is disposed between the tip of the arm 21 of the robot 2 and the rotary driver 6, but this is not limiting. For example, the coupling 9 may be configured to be extendable and retractable in the axial direction, and the feed device 5 may operate to extend and retract the coupling 9, thereby moving the mandrel 41. [Explanation of symbols]

[0059] 1 Automatic tube expansion device 2. Robot 3. Tube expansion device 4 Expander 41 Mandrel 42 Frame members 43 Laura 44 frames 451 color rear wheel 452 Ball Cage 453 Colored front wheels (colored parts) 5 Feeder 51 Feed cylinder 521 Piston 522 Piston rod 54 base plate 55 Support part 6 Rotary drive machine 7 Clamping device 8. Clamp moving device 81 Cylinder body 821 Piston 822 Piston rod 10 Control device T-tube

Claims

1. A robot, A tube expanding device that moves while being supported by the robot and performs tube expanding processing, A mandrel, a collar member slidably supported on the mandrel; a cylindrical frame rotatably supported inside the collar member; a plurality of rollers rotatably held by the frame; an expander having a rotary drive that rotates the mandrel; a clamping device for clamping the collar member; a clamp moving device that moves the clamp device in the axial direction of the expander; A feeding device that moves the mandrel in the axial direction of the expander, a base plate having a support portion and fixed to the robot; a feed cylinder that generates a driving force by compressed air; a piston slidably disposed within the feed cylinder; a piston rod having a base end fixed to the piston and a tip end extending from the feed cylinder and connected to the support portion; a feeder having a tube expanding device having An automatic tube expanding device equipped with:

2. A colored rear wheel is fixed to the outer peripheral surface of the frame, the collar member is rotatably disposed on the tip side of the expander with respect to the collar rear wheel via a ball retainer; The automatic tube expanding device according to claim 1.

3. a control device that operates the feeding device to move the mandrel in the direction of the axial external force while the mandrel is subjected to the axial external force, thereby causing the position of the mandrel to follow the axial movement of the mandrel. The automatic tube expanding device according to claim 1 or 2.

4. the control device controls the axial position of the clamp device to release the holding force of the clamp moving device when the clamp moving device moves the clamp device toward the front end of the mandrel and the collar member is clamped by the clamp device. The automatic tube expanding device according to claim 3.

5. The clamp moving device is A cylinder body that generates driving force using compressed air; a piston slidably disposed within the cylinder body; a piston rod having a base end fixed to the piston and a tip end extending from the cylinder body and connected to the clamp device; The automatic tube expanding device according to claim 1 or 2.

6. a clamp moving device that moves a frame member having a frame on which a roller is rotatably held toward a front end side of the mandrel relative to the mandrel on which the frame member is fitted; a clamping device clamping the frame member; a robot inserting the frame member and the mandrel into a tube; When the frame member and the mandrel reach a predetermined position, the robot stops; a feeding device feeding the mandrel, which is rotated in one direction by a rotary drive device, to a tip end side; The frame rotates in the one direction to self-propel the mandrel in a distal direction; The roller expands the tube, When the load torque of the rotary drive machine reaches a predetermined set torque, the rotary drive machine temporarily stops the rotation of the mandrel, The rotary driver rotates the mandrel in the other direction, which is the opposite direction to the one direction, and the frame rotates in the other direction, causing the mandrel to self-retract in the base end direction; the feeding device pulls the mandrel rotating in the other direction back toward the base end, the robot withdraws the frame member and the mandrel from the tube; An automatic tube expansion method, comprising: When the mandrel rotates in the one direction and self-propels toward the distal end, and when the mandrel rotates in the other direction and self-retreats toward the proximal end, and when the mandrel is subjected to an axial external force, the feeding device moves the mandrel in the direction of the axial external force, so that the position of the mandrel follows the axial movement of the mandrel. Automatic tube expansion method.

7. the clamp moving device moves the clamp device toward the front end of the mandrel and, in a state in which the frame member is clamped by the clamp device, releases the holding force of the clamp moving device on the axial position of the clamp device. The automatic tube expanding method according to claim 6.

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