Expanded connection equipment, industrial robot and control method of industrial robot

Abstract

The invention provides expanded connection equipment, an industrial robot and a control method of the industrial robot, and relates to the technical field of industrial robots. The expanded connection equipment comprises a hydraulic expansion gun, a piston in a hydraulic cylinder of the hydraulic expansion gun is used for driving a push rod of the hydraulic gun to push an expansion head of the hydraulic expansion gun; the first detection device is used for detecting the displacement amount of the piston or the push rod, and the first detection device is connected with a control system of the industrial robot; and the visual sensor is arranged at the mechanical arm, the visual sensor is used for identifying the position of a pipe in front of the hydraulic expansion gun, and the visual sensor is connected with a control system of the industrial robot. The piston of the hydraulic expansion gun is controlled by the hydraulic system to stop advancing, so that the expansion head is prevented from continuously performing expansion joint on the pipe, and the control response to the pipe expansion driving force in the pipe expansion process is quick.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial robots, and in particular to an expansion joint device, an industrial robot and a control method thereof. Background Art

[0002] The connection between tubes and tube sheets is one of the main processes in the production of shell-type heat exchangers. The connection between heat exchange tubes and tube sheets is generally made by welding, and this welding process is called tube sheet welding.

[0003] Before welding, the heat exchange tubes need to be expanded and positioned. In the prior art, expansion equipment is generally used to position and expand a large number of tubes on the tube sheet, then spot weld and fix them, and then fully weld them.

[0004] In the prior art, expansion equipment generally uses robotic equipment to achieve expansion, such as the invention patent with patent number 201810184802.0, entitled Automatic Expansion System and Expansion Method, which achieves expansion by pushing up with the elastic force of a spring to achieve the expansion function of the pipe.

[0005] Although the aforementioned closest prior art can realize the expansion of tube sheets and effectively avoid damage to tubes during the expansion process, the driving force of the device uses spring force, and the elastic force of the spring is uncontrollable. During the process of releasing the elastic force of the spring, if the expansion needs to be stopped immediately, the spring cannot be stopped from rebounding immediately, and can only be achieved by moving the mechanical arm outward. As a result, the control response of the expansion driving force during the expansion process is not fast. Summary of the invention

[0006] The technical problem to be solved by the present invention is that the elastic force of the spring in the positioning expansion device driven by spring expansion joint is uncontrollable, resulting in a slow control response to the expansion driving force during the expansion process.

[0007] In order to solve the above problems, the present invention provides an expansion device, which is used for an industrial robot and comprises:

[0008] A hydraulic expansion gun is arranged at the mechanical arm of the industrial robot. The hydraulic expansion gun drives the push rod of the hydraulic gun to push the expansion head of the hydraulic expansion gun through the piston in the hydraulic cylinder of the hydraulic expansion gun, so that the expansion head diameter of the expansion gun increases. The hydraulic system of the hydraulic expansion gun is connected to the control system of the industrial robot;

[0009] a first detection device, disposed at the hydraulic expansion gun, for detecting a displacement of the piston or the push rod, and connected to a control system of the industrial robot; and

[0010] A visual sensor is arranged at the mechanical arm, and is used to identify the position of the pipe in front of the hydraulic expansion gun. The visual sensor is connected to the control system of the industrial robot.

[0011] Optionally, the expansion joint device further comprises:

[0012] A pneumatic vibrator is arranged at the hydraulic expansion gun, and is used to drive the hydraulic expansion gun to vibrate.

[0013] Optionally, the expansion joint device further comprises:

[0014] A frame structure connected to the mechanical arm of the industrial robot, wherein the hydraulic expansion gun is arranged in the frame structure;

[0015] A plurality of elastic members are arranged axially around the hydraulic expansion gun, the elastic members connect the frame structure with the hydraulic expansion gun, and the elastic members are used for elastic deformation; and

[0016] A plurality of second detection devices are arranged at the elastic member in a one-to-one correspondence, the second detection devices are used to detect the elastic deformation of the elastic member, and the plurality of second detection devices are connected to the control system of the industrial robot.

[0017] Optionally, the frame structure includes a first outer frame, a second outer frame, a first inner sleeve and a second inner sleeve, the ends of the mechanical arm are connected to the first outer frame and the second outer frame respectively, the first inner sleeve is sleeved outside the front end of the hydraulic expansion gun, and the second inner sleeve is sleeved outside the rear end of the hydraulic expansion gun;

[0018] The first inner sleeve is arranged in the first outer frame, the second inner sleeve is arranged in the second outer frame, the first inner sleeve and the first outer frame are connected through a plurality of corresponding elastic members, and the plurality of elastic members between the first inner sleeve and the first outer frame are arranged around the first inner sleeve,

[0019] The second inner sleeve is connected to the second outer frame via a plurality of corresponding elastic members, and the plurality of elastic members between the second inner sleeve and the second outer frame are arranged around the second inner sleeve.

[0020] Optionally, the frame structure further comprises a first fixing seat, the first fixing seat is detachably connected to the second inner sleeve, and the pneumatic vibrator is detachably connected to the first fixing seat;

[0021] The push rod is connected to the piston, and the front end of the push rod extends out of the hydraulic cylinder and is inserted into the expansion head;

[0022] When the piston is in contact with the rear end of the hydraulic cylinder, a gap is formed between the front end of the push rod and the front end of the expansion head, the rear end of the push rod extends out of the rear end of the hydraulic cylinder, and the vibrating end of the pneumatic vibrator is in contact with the rear end of the push rod, and the pneumatic vibrator is used to push the push rod to vibrate forward;

[0023] The hydraulic system of the hydraulic expansion gun is adapted to allow the piston to move freely within the hydraulic cylinder.

[0024] Optionally, a protruding structure is provided at the rear end of the piston, the rear end of the protruding structure extends out of the rear end of the hydraulic cylinder, the push rod is inserted into the protruding structure and the piston, and the rear end of the push rod extends out of the rear end of the protruding structure;

[0025] The first fixing seat is a long strip plate-like member bent around its wide side into a U-shape, the protruding structure and the rear end of the push rod are placed in the hollow of the first fixing seat, and the two ends of the U-shape of the first fixing seat are detachably connected to the second inner sleeve respectively.

[0026] The pneumatic vibrator and the first detection device can be detachably arranged outside the first fixing seat, the first detection device is connected to the protruding structure, and the first detection device is used to detect the displacement of the protruding structure;

[0027] The expansion joint device further comprises a second fixing seat, wherein the second fixing seat is used to replace the first fixing seat.

[0028] The pneumatic vibrator and the first detection device can be detachably arranged outside the second fixing seat, and the second fixing seat is detachably connected to the second outer frame.

[0029] The first detection device is a self-resetting displacement sensor, and the moving end of the first detection device passes through the second fixing seat and is connected to the rear end of the protruding structure.

[0030] Optionally, the expansion joint device further comprises a top plate, two slide rails, two slide seats, two slide sleeves, two third detection devices, two push rods and two springs.

[0031] The top plate is connected to the end of the mechanical arm, and the third detection device is a proximity switch;

[0032] The two slide rails are arranged parallel to each other at the bottom of the top plate, each slide seat is clamped on one of the slide rails, and the slide seat is used to reciprocate along the slide rails. The bottom of the slide seat is connected to the top of the frame structure.

[0033] The sliding sleeve is arranged at the bottom of the top plate, each of the top rods is sleeved in one of the sliding sleeves, each of the springs is sleeved outside one of the top rods, a limiting protrusion is arranged at the front end of the top rod, the limiting protrusion is used to prevent the spring from being separated from the top rod, the spring is arranged between the limiting protrusion and the sliding sleeve, the spring is in an extended state, and the front end of the top rod supports the frame structure;

[0034] Two third detection devices are arranged at the frame structure, a sensing end of one third detection device is arranged toward the rear end of the slide rail, and a sensing end of the other third detection device is arranged toward the slide rail.

[0035] In addition, the present invention also provides an industrial robot, which includes the expansion device.

[0036] In addition, the present invention also provides a control method, which is used for the industrial robot, and the control method includes:

[0037] Use vision sensors to position tubes on tube sheets;

[0038] Expanding the pipe using a hydraulic expansion gun, and detecting the displacement of a push rod of the hydraulic expansion gun by a first detection device;

[0039] Using the visual sensor to detect in real time whether the outer diameter of the pipe reaches the set expansion diameter;

[0040] When the outer diameter of the pipe reaches the set expansion diameter, the hydraulic expansion gun stops expanding;

[0041] The set pipe is marked, and when the outer diameter of the set pipe reaches the set expansion diameter, the displacement of the push rod of the hydraulic expansion gun does not reach or exceed the set movement distance.

[0042] Optionally, the industrial robot further comprises a pneumatic vibrator, which is arranged at the hydraulic expansion gun, and when the piston is in contact with the rear end of the hydraulic cylinder, a gap is formed between the front end of the push rod and the front end of the expansion head;

[0043] Before the pipe is expanded by using a hydraulic expansion gun, the method further comprises:

[0044] Based on the length of the pipe detected by the visual sensor, determining whether to flatten the pipe;

[0045] If it is necessary to flatten the pipe, the piston of the hydraulic expansion gun is kept stationary, the pneumatic vibrator is vibrated, and the mechanical arm is controlled to make the expansion head flatten the pipe;

[0046] Expanding the pipe using a hydraulic expansion gun includes:

[0047] Determining whether the tube is a thin-walled tube;

[0048] If the tube is a thin-walled tube, the piston is adapted to move freely in the hydraulic expansion gun and to vibrate the pneumatic vibrator.

[0049] The technical effects of the present invention include at least:

[0050] The hydraulic expansion gun, the first detection device and the visual sensor of the expansion equipment are used to realize precise control of the hydraulic expansion gun during the expansion process; in particular, when the visual sensor detects that the outer diameter of the tube is less than the set outer diameter, and the displacement of the piston or the push rod detected by the first detection device does not reach the set distance, the control system continues to advance the piston through the hydraulic system, thereby realizing the expansion of the tube by the expansion head; and when the visual sensor detects that the outer diameter of the tube is greater than the set outer diameter or has reached the set expansion diameter, that is, when it is detected that the expansion needs to be stopped immediately, the control system of the industrial robot immediately controls the piston of the hydraulic expansion gun to stop advancing through the hydraulic system and immediately moves backward, so that the diameter of the expansion head is quickly reduced to prevent the expansion head from continuing to expand the tube, thereby realizing rapid control response of the expansion driving force during the expansion process. Thus, the technical problem that the elastic force of the spring in the positioning expansion device driven by the spring in the prior art is uncontrollable, resulting in a slow control response of the expansion driving force during the expansion process.

[0051] Furthermore, a pneumatic vibrator is arranged at the hydraulic expansion gun, and the hydraulic expansion gun is connected to the frame structure through an elastic member, and the frame structure is connected to the mechanical arm. In this way, when the pneumatic vibrator vibrates, the elastic member can be deformed by elastic force, so that the multiple elastic members around the hydraulic expansion gun can absorb a large amount of vibration generated by the pneumatic vibrator, thereby blocking the vibration. The pneumatic vibrator can only vibrate the hydraulic expansion gun, and will not transmit the vibration to the mechanical arm through the frame structure, thereby avoiding other components installed at the mechanical arm, such as the visual sensor, from vibrating frequently, thereby extending the service life and maintenance cycle of the components at the end of the mechanical arm.

[0052] Furthermore, by utilizing the characteristic that the pneumatic vibrator is fixed at the first fixed seat, the pneumatic vibrator cannot move with the piston, so that the telescopic end of the pneumatic vibrator can only push the piston within a set range. When the piston is pushed to a certain distance by the pneumatic vibrator, the pneumatic vibrator can no longer push the piston, so that the push rod can no longer continue to push the expansion head to continue to expand, thereby preventing the expansion head from continuing to expand the thin-walled tube, and avoiding the pneumatic vibrator from pushing the piston too much, causing the expansion head to expand too much, resulting in the tube end of the thin-walled tube being cracked, so as to successfully achieve the positioning expansion of the thin-walled tube.

[0053] Furthermore, the second fixing seat is connected to the second outer frame, and the pneumatic vibrator is connected to the second fixing seat, and the pneumatic vibrator generates vibrations on the rear end of the push rod, which can not only ensure that the vibration is transmitted to the piston rod and the expansion head, but also utilize the elastic deformation of multiple elastic members arranged between the second outer frame and the second inner sleeve, so that the elastic members absorb the vibrations transmitted to the second outer frame by the telescopic end of the pneumatic vibrator through the hydraulic cylinder and the second inner sleeve, thereby greatly reducing the vibrations received by the second fixing seat. This makes the vibration received by the first detection device installed on the second fixing seat smaller than the vibration received by the hydraulic cylinder. At the same time, the high detection sensitivity of the first detection device is utilized to realize the inspection of the vibration range of the hydraulic cylinder in the front-to-back direction, so that the pushing force of the end of the mechanical arm on the expansion head can be adjusted according to the vibration range in the front-to-back direction. At the same time, in the process of leveling the pipe, the vibration frequency of the pneumatic vibrator can also be adjusted based on the detection of the first detection device, thereby adjusting the vibration amount of the expansion head along the front-to-back direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A schematic perspective view of the robot device for tube sheet expansion according to a specific embodiment of the present invention;

[0055] Figure 2 A schematic longitudinal cross-sectional view of the robot device for tube sheet expansion according to a specific embodiment of the present invention;

[0056] Figure 3 A schematic flow chart of the main steps of the control method according to a specific embodiment of the present invention;

[0057] Figure 4 The present invention is a schematic flow chart of all steps of the control method according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0058] In order to make the above-mentioned purpose, features and advantages of the present invention more obvious and easy to understand, the specific implementation mode of the present invention is described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the embodiments of the present application. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present invention. The embodiments of the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0059] It is understood that the terms "first", "second", etc. used in this application can be used in this article to describe various professional terms, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. However, unless otherwise specified, these professional terms are not limited by these terms. These terms are only used to distinguish one professional term from another professional term. For example, without departing from the scope of this application, the first receiving device and the second receiving device are different receiving devices, the first surface and the second surface are different surfaces, and the first plane, the second plane, the third plane and the fourth plane are different planes. In the description of the embodiments of the present application, the meaning of "multiple" and "several" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0060] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0061] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than the horizontal height of the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0062] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0063] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this application and in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0064] Moreover, the Z-axis in the accompanying drawings represents the vertical direction, that is, the up and down direction, and the positive direction of the Z-axis (that is, the direction of the arrow of the Z-axis) represents the top, and the negative direction of the Z-axis (that is, the direction opposite to the positive direction of the Z-axis) represents the bottom; the X-axis in the accompanying drawings represents the longitudinal direction, that is, the front and back direction, and the positive direction of the X-axis (that is, the direction of the arrow of the X-axis) represents the front, and the negative direction of the X-axis (that is, the direction opposite to the positive direction of the X-axis) represents the back; it should be noted that the aforementioned Z-axis and X-axis are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0065] See also Figures 1 to 4 This embodiment provides an expansion joint device, which is used for an industrial robot and includes:

[0066] A hydraulic expansion gun 300 is arranged at the mechanical arm of the industrial robot. The hydraulic expansion gun 300 drives a push rod 320 of the hydraulic gun to push the expansion head 310 of the hydraulic expansion gun 300 through a piston 350 in a hydraulic cylinder 340 thereof, so as to increase the diameter of the expansion head 310 of the expansion gun. The hydraulic system of the hydraulic expansion gun 300 is connected to the control system of the industrial robot.

[0067] a first detection device 260, which is disposed at the hydraulic expansion gun 300, and is used to detect the displacement of the piston 350 or the push rod 320, and the first detection device 260 is connected to the control system of the industrial robot; and

[0068] The visual sensor 700 is arranged at the robot arm. The visual sensor 700 is used to identify the position of the pipe in front of the hydraulic expansion gun 300. The visual sensor 700 is connected to the control system of the industrial robot.

[0069] Preferably, the hydraulic expansion gun 300 is arranged in the frame structure 200, and the hydraulic expansion gun 300 also includes a fuselage 330, the hydraulic cylinder 342 and the push rod 320 are both arranged in the fuselage 330, the push rod 320 is inserted at the axis of the hydraulic cylinder 342 and connected to the piston 350 in the hydraulic cylinder 342, the push rod 320 extends out of the front end of the fuselage 330, the expansion head 310 is a hollow structure and is connected to the front end of the fuselage 330, the push rod 320 is inserted into the expansion head 310, the rear end of the piston 350 is provided with a protruding structure 351, the protruding structure 351 extends out of the hydraulic cylinder 340, the push rod 320 is sleeved in the protruding structure 351, and the rear end of the push rod 320 extends out of the hydraulic cylinder 340.

[0070] It should be noted that the visual sensor 700 here may include a line laser transmitter and a camera. By using the principle of triangulation, the camera collects the line laser pattern reflected on the tube sheet and the tube irradiated by the line laser transmitter, and calculates the center position of the tube and the distance between the tube end and the expansion gun based on this.

[0071] In addition, it should be noted that the control system here may refer to a computer and has the function of autonomously generating corresponding programs. For example, it may autonomously generate positioning expansion paths for multiple tubes on a tube sheet based on design parameters and detection parameters detected by the visual sensor 700.

[0072] When positioning expansion, the industrial robot's visual sensor is used to position the tubes on the tube sheet. Visual Positioning After the robot arm makes the expansion head of the expansion equipment accurately approach the tube on the tube sheet, after the expansion head of the hydraulic expansion gun is aligned and inserted into the tube, the control system of the robot controls the hydraulic expansion gun to make the piston drive the push rod of the hydraulic gun to push the expansion head of the hydraulic expansion gun, so that the diameter of the expansion head of the expansion gun is increased, thereby positioning and expanding the tube on the tube sheet, and detecting the displacement of the piston or the push rod through the first detection device.

[0073] In this process, visual sensors are used for real-time identification and detection, so that the control system can obtain the outer diameter information of the pipe in real time. If the control system finds that the outer diameter of the pipe is greater than the set outer diameter or has reached the set expansion diameter, at this time, regardless of whether the displacement of the piston or push rod detected by the first detection device is within the set safety range, or regardless of whether the set movement distance is reached, the control system immediately moves the piston backward through the hydraulic system, thereby preventing the piston from continuing to push the expansion head, causing the expansion head diameter to increase and the pipe end to burst.

[0074] Furthermore, for tubes whose outer diameter is greater than the set outer diameter or has reached the set expansion diameter, and the displacement of the piston or push rod detected by the first detection device exceeds the set safety range, or exceeds the set movement distance, or does not reach the set distance, the control system can mark these tubes, and after all the tubes on the tube sheet are positioned and expanded, the control system can prompt the staff to inspect these marked tubes.

[0075] In this way, as described above, the hydraulic expansion gun, the first detection device and the visual sensor of the expansion equipment are used to achieve precise control of the hydraulic expansion gun during the tube expansion process; especially when the visual sensor detects that the outer diameter of the tube is smaller than the set outer diameter, and the displacement of the piston or the push rod detected by the first detection device does not reach the set distance, the control system continues to advance the piston through the hydraulic system, thereby achieving expansion of the tube by the expansion head; and when the visual sensor detects that the outer diameter of the tube is larger than the set outer diameter or has reached the set expansion diameter, that is, when it is detected that the expansion needs to be stopped immediately, the control system of the industrial robot immediately controls the piston of the hydraulic expansion gun to stop advancing through the hydraulic system, and immediately moves backward, so that the diameter of the expansion head is quickly reduced to prevent the expansion head from continuing to expand the tube, thereby achieving rapid control response of the expansion driving force during the tube expansion process.

[0076] This solves the technical problem that the elastic force of the spring in the positioning expansion device of the spring driven expansion joint in the prior art is uncontrollable, resulting in a slow control response to the expansion driving force during the expansion process.

[0077] See also Figure 1 and Figure 2 Furthermore, the expansion joint device further comprises:

[0078] A pneumatic vibrator 600 is provided at the hydraulic expansion gun 300, and the pneumatic vibrator 600 is used to drive the hydraulic expansion gun 300 to vibrate;

[0079] The frame structure 200 is connected to the mechanical arm of the industrial robot, and the hydraulic expansion gun 300 is arranged in the frame structure 200;

[0080] A plurality of elastic members 400 are arranged axially around the hydraulic expansion gun 300 , the elastic members 400 connect the frame structure 200 with the hydraulic expansion gun 300 , and the elastic members 400 are used for elastic deformation; and

[0081] A plurality of second detection devices 500 are disposed at the elastic member 400 in a one-to-one correspondence. The second detection devices 500 are used to detect the elastic deformation of the elastic member 400. The plurality of second detection devices 500 are connected to the control system of the industrial robot.

[0082] It should be noted that the pneumatic vibrator here can be connected to the cylinder body of the hydraulic cylinder, or the rear end of the piston can extend out of the hydraulic cylinder and the pneumatic vibrator can be connected to the rear end of the piston.

[0083] It should be noted that the hydraulic system in this embodiment includes an oil tank, a pipeline, a control valve, a hydraulic pump and a drive motor. The control valve, oil tank, hydraulic pump and hydraulic cylinder 340 are arranged in the pipeline. The control valve and the drive motor are respectively connected to the control system. The hydraulic pump is driven to rotate by the drive motor, so that the hydraulic oil in the oil tank is input into the hydraulic cylinder 340 on both sides of the piston 350 through the pipeline, and the pipeline is controlled by the control valve to drive the piston 350 to reciprocate.

[0084] More importantly, the control valve can also keep the oil ports at both ends of the hydraulic cylinder closed. For example, the control valve can be two solenoid valves and are respectively arranged at the oil ports at both ends of the hydraulic cylinder. When the two solenoid valves are closed, the piston remains stationary in the hydraulic cylinder. When the two solenoid valves are kept open and the hydraulic pump does not deliver hydraulic oil to the pipeline, the movement of the piston in the hydraulic cylinder is not restricted. At this time, the pneumatic vibrator can push the piston through the push rod to move the piston forward.

[0085] In addition, the pneumatic vibrator 600 here can be connected to an air pump, and the air pump provides an air source for the pneumatic vibrator 600.

[0086] The inventor of the present invention found that the preparation work before the positioning expansion process takes a long time when analyzing and studying the existing positioning expansion equipment. This is because it is necessary to first check whether the ends of the tubes inserted in the tube sheet are flat. If they are not flat, manual operation is required to flatten the tubes with too long ends to the set length. In this process, experienced operators are required to use rubber hammers or copper hammers to gently tap the tube end faces to avoid damage to the tubes and tube sheets during the flattening process. A large number of tubes are often inserted into the tube sheet, which results in experienced operators spending a lot of time to perform the aforementioned flattening operations one by one, which results in a long preparation work before the positioning expansion process.

[0087] To this end, the distance between the tube end and the expansion gun can be detected based on the visual sensor 700, and the tube length can be calculated. Then, the tube with too long tube end length can be known, and the tube with too long tube end can be marked as a tube that needs to be flattened. In this process, the mechanical arm can be used to drive the visual sensor to identify the tube end lengths of multiple tubes one by one. Then, the control system causes the mechanical arm expansion head to be inserted into the tube marked as a tube that needs to be flattened. Then the control system causes the pneumatic vibrator 600 to vibrate the hydraulic expansion gun, so that the vibration is transmitted to the expansion head of the hydraulic expansion gun, and then transmitted to the tube through the expansion head, so that vibration is generated between the tube and the tube sheet, so that the fit between the tube and the tube sheet is looser. In this way, the tube can be pushed to the set position in the tube sheet more easily. At the same time, the control system causes the end of the mechanical arm to push the expansion head 310 to continue to push the tube into the tube sheet. Under the premise of ensuring that the tube and the tube sheet are not damaged, the tube with too long length can be pushed into the tube sheet quickly and safely.

[0088] In this way, with the assistance of the visual sensor 700, the pneumatic vibrator and the hydraulic expansion gun 300 cooperate with each other to push the excessively long tube into the tube sheet intact, thereby completely replacing the method in which the operator uses a rubber hammer or a copper hammer to gently tap the end face of the tube to level the tube. This not only ensures the accuracy of subsequent positioning expansion and avoids damage to the tube sheet and the tube, but also greatly improves the efficiency of leveling the tube, thereby greatly shortening the preparation time before the positioning expansion process.

[0089] In addition, misalignment is prone to occur when the expansion head is inserted into the tube at the end of the robot arm. In this embodiment, the frame structure and multiple elastic members cooperate with each other to avoid this situation.

[0090] Specifically, the robot arm brings the frame structure 200 close to a tube at the tube sheet, so that the expansion head 310 is inserted into the tube; in this process, in order to avoid execution errors, multiple elastic members 400 and multiple second detection devices 500 are used to determine whether the expansion head 310 is accurately inserted into the tube. If the expansion head 310 is not accurately inserted into the tube, the expansion head 310 will be skewed relative to the tube, so that the elastic member 400 on the skewed side will be elastically deformed, and the corresponding second detection device 500 will detect the deformation of the elastic member. At this time, the control system can adjust the end position of the robot arm based on the deformation detected by the second detection device 500, until the deformation of all the elastic members detected by the second detection devices 500 is within a reasonable set range, and then the expansion head is smoothly inserted into the tube, so as to realize adaptive adjustment of the intubation process;

[0091] Alternatively, when a second detection device 500 detects that the deformation of the corresponding elastic member 400 seriously exceeds the set maximum deviation, the control system can directly move the end of the robot arm away from the tube sheet, thereby separating the expansion head 310 from the tube, so as to avoid the expansion head 310 from causing damage to the tube as much as possible.

[0092] In this way, the frame structure 200, the plurality of elastic members 400, the plurality of second detection devices 500 and the hydraulic expansion gun 300 cooperate with each other to ensure that the expansion head 310 of the hydraulic expansion gun 300 can be safely inserted into the pipe.

[0093] In addition, considering the huge number of tubes on the tube sheet, the number of flat tubes required may also be very large, which results in the need for frequent vibration of the pneumatic vibrator.

[0094] This has created new technical problems: the frequent vibration of the pneumatic vibrator leads to frequent maintenance of the parts at the end of the robot arm and shortens their service life, especially for the lasers, cameras and other precision optical components in the visual sensor.

[0095] In order to solve the new problems caused by the use of pneumatic vibrators, in this embodiment, the pneumatic vibrator is set at the hydraulic expansion gun, and the hydraulic expansion gun is connected to the frame structure through an elastic member, and the frame structure is connected to the mechanical arm. In this way, when the pneumatic vibrator vibrates, the elastic member can be deformed by elastic force, so that the multiple elastic members around the hydraulic expansion gun can absorb a large amount of vibration generated by the pneumatic vibrator, thereby achieving a vibration blocking effect. The pneumatic vibrator can only vibrate the hydraulic expansion gun, and will not transmit the vibration to the mechanical arm through the frame structure, thereby avoiding other components installed at the mechanical arm, such as the visual sensor, from vibrating frequently, thereby extending the service life and maintenance cycle of the components at the end of the mechanical arm.

[0096] In addition, it should be noted that the method of using the industrial robot in this embodiment can be:

[0097] When in use, first enter the design parameters of the tube sheet into the control system, that is, into the industrial robot. For example, the drawing of the tube sheet can be input through the input end; then the mechanical arm is moved close to the tube sheet, and the detection parameters of the tube sheet are obtained using the visual sensor 700. For example, the mechanical arm can be controlled to allow the visual sensor 700 to obtain images of all tubes on the surface of the tube sheet along an S-shaped route at the plate surface of the tube sheet, thereby obtaining the exposed length of all tubes on the surface of the tube sheet, the inner diameter, the outer diameter, the axis of the tube, and other related detection parameters. Then, the entered tube sheet design parameters and the obtained detection parameters are checked, and the tubes whose tube length in the detection parameters exceeds the set range are marked as tubes that need to be flattened.

[0098] Then, the robot arm positions and expands the tubes on the tube sheet one by one according to the set route. Of course, the control system can also autonomously generate a sequential route for positioning and expanding multiple tubes on the tube sheet based on the previously acquired detection parameters. In addition, for the setting of the control system, centralized tube flattening can be adopted, that is, after flattening multiple tubes that need to be flattened, the tubes on the tube sheet are positioned and expanded one by one according to the set route; or the tubes that need to be flattened can be flattened while positioning and expanding the tubes on the tube sheet one by one according to the set route.

[0099] Next, after the automatic flat pipe, the aforementioned positioning expansion operation is performed for pipes of conventional wall thickness.

[0100] Then, the hydraulic system fills the hydraulic cylinder 340 in front of the piston 350 with hydraulic oil, so that the piston 350 moves backward, thereby separating the push rod 320 from the expansion head 310, shrinking the front end of the expansion head 310, and then controlling the mechanical arm to separate the hydraulic expansion gun from the pipe that has been expanded.

[0101] See also Figures 1 to 4Further, the frame structure 200 includes a first outer frame 210, a second outer frame 220, a first inner sleeve 230 and a second inner sleeve 240, the ends of the mechanical arm are respectively connected to the first outer frame 210 and the second outer frame 220, the first inner sleeve 230 is sleeved outside the front end of the hydraulic expansion gun 300, and the second inner sleeve 240 is sleeved outside the rear end of the hydraulic expansion gun 300;

[0102] The first inner sleeve 230 is disposed in the first outer frame 210, and the second inner sleeve 240 is disposed in the second outer frame 220. The first inner sleeve 230 and the first outer frame 210 are connected via a plurality of corresponding elastic members, and a plurality of elastic members between the first inner sleeve 230 and the first outer frame 210 are disposed around the first inner sleeve 230.

[0103] The second inner sleeve 240 is connected to the second outer frame 220 via a plurality of corresponding elastic members, and the plurality of elastic members between the second inner sleeve 240 and the second outer frame 220 are disposed around the second inner sleeve 240 .

[0104] The first outer frame 210 cooperates with the first inner sleeve 230, the second outer frame 220 cooperates with the second inner sleeve 240, and the plurality of elastic members 400 cooperate to realize floating support for the hydraulic expansion gun 300. When the expansion head 310 is docked with the pipe, the expansion head 310 can float and be accurately inserted into the pipe according to actual needs.

[0105] Preferably, there are eight elastic members 400, and eight second detection devices 500, four elastic members 400 form a group, one group of elastic members 400 is arranged in the first outer frame 210, and the other group of elastic members 400 is arranged in the second outer frame 220, and each group of elastic members 400 is arranged outside the corresponding first inner sleeve 230 or the second inner sleeve 240 in the form of top, bottom, left and right, respectively. This not only reduces the number of elastic members 400, but also ensures that the elastic members 400 can float and support all possible movement directions of the hydraulic expansion gun 300, and cooperate with the corresponding second detection device 500 to realize accurate detection of the movement of the hydraulic expansion gun 300 in multiple directions.

[0106] See also Figures 1 to 4 , further, the frame structure 200 further includes a first fixing seat 250, the first fixing seat 250 is detachably connected to the second inner sleeve 240, and the pneumatic vibrator 600 is detachably connected to the first fixing seat 250;

[0107] The push rod 320 is connected to the piston 350 , and the front end of the push rod 320 extends out of the hydraulic cylinder 340 and is inserted into the expansion head 310 ;

[0108] When the piston 350 is in contact with the rear end of the hydraulic cylinder 340, a gap is formed between the front end of the push rod 320 and the front end of the expansion head 310, the rear end of the push rod 320 extends out of the rear end of the hydraulic cylinder 340, and the vibrating end of the pneumatic vibrator 600 is in contact with the rear end of the push rod 320, and the pneumatic vibrator 600 is used to push the push rod 320 to vibrate forward;

[0109] The hydraulic system of the hydraulic expansion gun 300 is adapted to allow the piston 350 to move freely within the hydraulic cylinder 340 .

[0110] It should be noted that the vibration forward movement here means vibration and forward movement.

[0111] It should be noted that the pneumatic vibrator 600 here can be a cylinder piston type, and the piston 350 is connected to the piston rod. The piston rod here is the telescopic end of the pneumatic vibrator 600. The rear end of the push rod 320 and at least one of the protruding structures 351 are connected to the piston rod, and the cylinder is connected through a pipeline to drive the piston rod to move back and forth, thereby achieving a vibration effect.

[0112] By setting the control system so that it can obtain the inner diameter and outer diameter of the pipe through the visual sensor 700, the wall thickness of the pipe can be calculated, or the control system can determine whether the pipe is a thin-walled pipe based on the pipe wall thickness through the previously entered design parameters; of course, the pipe can also be directly set to be a thin-walled pipe or a pipe with conventional wall thickness.

[0113] Next, after the automatic flattening of the pipe, the pipe with normal wall thickness is positioned and expanded. The positioning and expansion operation can be performed as described above and will not be explained here.

[0114] As for the positioning expansion of the thin-walled tube, the control system controls the hydraulic system to allow the piston 350 to move freely in the hydraulic cylinder 340, that is, to keep the piston 350 in a follow-up state in the hydraulic cylinder 340, and then the control system vibrates the pneumatic vibrator 600 to push the piston 350 or the push rod 320 to move forward a small amount, so that the push rod 320 moves forward a small amount. At the same time, the front end of the push rod 320 and the front end of the expansion head 310 are set with a gap, so that the push rod 320 can push the expansion head 310 at its front end during the process of being vibrated forward by the pneumatic vibrator, so that the expansion head 310 is slightly expanded.

[0115] More importantly, by utilizing the characteristic that the pneumatic vibrator 600 is fixed at the first fixed seat 250, the pneumatic vibrator 600 cannot move with the piston 350, so that the telescopic end of the pneumatic vibrator 600 can only push the piston 350 within a set range. When the piston 350 is pushed to a certain distance by the pneumatic vibrator 600, the pneumatic vibrator 600 can no longer push the piston 350, so that the push rod 320 can no longer continue to push the expansion head 310 to expand, thereby preventing the expansion head from continuing to expand the thin-walled tube, and avoiding the pneumatic vibrator 600 from exerting too much thrust on the piston 350, causing the expansion head 310 to expand too much, resulting in the tube end of the thin-walled tube being burst, so as to smoothly achieve the positioning expansion of the thin-walled tube.

[0116] See also Figures 1 to 4 Further, the rear end of the piston 350 is provided with a protruding structure 351, the rear end of the protruding structure 351 extends out of the rear end of the hydraulic cylinder 340, the push rod 320 is inserted into the protruding structure 351 and the piston 350, and the rear end of the push rod 320 extends out of the rear end of the protruding structure 351;

[0117] The first fixing seat 250 is a long strip plate-like member bent around its wide side into a U-shape, the protruding structure 351 and the rear end of the push rod 320 are placed in the hollow of the first fixing seat 250, and the two ends of the U-shape of the first fixing seat 250 are detachably connected to the second inner sleeve 240 respectively.

[0118] The pneumatic vibrator 600 and the first detection device 260 can be detachably disposed outside the first fixing seat 250 . The first detection device 260 is connected to the protruding structure 351 . The first detection device 260 is used to detect the displacement of the protruding structure 351 .

[0119] See also Figures 1 to 4 Furthermore, the expansion joint device further comprises a second fixing seat, and the second fixing seat is used to replace the first fixing seat 250.

[0120] The pneumatic vibrator 600 and the first detection device 260 can be detachably arranged outside the second fixing seat, and the second fixing seat is detachably connected to the second outer frame 220.

[0121] The first detection device 260 is a self-resetting displacement sensor, and the moving end of the first detection device 260 passes through the second fixing seat and is connected to the rear end of the protruding structure 351 .

[0122] During use, the second fixing seat is connected to the second outer frame 220, and the pneumatic vibrator 600 is connected to the second fixing seat, and the pneumatic vibrator 600 generates vibrations on the rear end of the push rod 320, so that the vibration can be transmitted to the piston rod and the expansion head 310, and the elastic members 400 arranged between the second outer frame 220 and the second inner sleeve 240 can be deformed by elastic force, so that the elastic members 400 absorb the vibration transmitted to the second outer frame 220 by the telescopic end of the pneumatic vibrator 600 through the hydraulic cylinder 340 and the second inner sleeve 240, thereby greatly reducing the vibration of the second fixing seat. This makes the vibration of the first detection device 260 installed on the second fixing seat smaller than the vibration of the hydraulic cylinder 340, and at the same time, the first detection device 260 has a high detection sensitivity, so as to realize the inspection of the vibration range of the hydraulic cylinder 340 in the front and rear directions, so that the pushing force of the end of the mechanical arm on the expansion head 310 can be adjusted according to the vibration range in the front and rear directions. Meanwhile, during the pipe flattening process, the vibration frequency of the pneumatic vibrator 600 may be adjusted based on the detection of the first detection device 260 , thereby adjusting the vibration amount of the expansion head 310 along the front-rear direction.

[0123] In addition, the high detection accuracy of the first detection device 260 is also utilized to accurately detect the movement of the piston 350 during the positioning expansion process, so as to prevent the piston 350 from pushing the push rod 320 to move too much, causing the expansion head 310 to expand too much and causing the tube mouth to burst.

[0124] See also Figures 1 to 4 Furthermore, the expansion joint device further comprises a top plate 110, two slide rails 120, two slide seats 130, two slide sleeves 140, two third detection devices 150, two ejector rods 160 and two springs 170.

[0125] The top plate 110 is connected to the end of the mechanical arm, and the third detection device 150 is a proximity switch;

[0126] The two slide rails 120 are arranged parallel to each other at the bottom of the top plate 110, and each slide seat 130 is clamped on one of the slide rails 120. The slide seat 130 is used to reciprocate along the slide rail 120. The bottom of the slide seat 130 is connected to the top of the frame structure 200.

[0127] The sliding sleeve 140 is arranged at the bottom of the top plate 110, each of the top rods 160 is sleeved in one of the sliding sleeves 140, each of the springs 170 is sleeved outside one of the top rods 160, a limiting protrusion is arranged at the front end of the top rod 160, and the limiting protrusion is used to prevent the spring 170 from being separated from the top rod 160, and the spring 170 is arranged between the limiting protrusion and the sliding sleeve 140, and the spring 170 is in an extended state, and the front end of the top rod 160 supports the frame structure 200;

[0128] The two third detection devices are arranged at the frame structure 200 , the sensing end of one of the third detection devices is arranged toward the rear end of the slide rail 120 , and the sensing end of the other third detection device is arranged toward the slide rail 120 .

[0129] Preferably, each slide rail 120 is provided with slide grooves on both sides of the long side, and the slide grooves are arranged along the extension direction of the slide rail 120. The top surface of the slide seat 130 is recessed in the center, and clamping arms are provided on both sides of the top surface. The two clamping arms are respectively clamped in the slide grooves, so that the clamping arms can only move back and forth in the slide grooves, thereby preventing the slide seat 130 from detaching from the slide rail 120.

[0130] In addition, the second detection device may also be a proximity switch.

[0131] Under normal circumstances, when the end of the mechanical arm pushes the hydraulic expansion gun 300 to move, the end of the mechanical arm drives the top plate 110 to move, and then pushes the top rod 160 forward through the top plate 110, the sliding sleeve 140 and the spring 170 in sequence, so that the top rod 160 pushes the frame structure 200 to follow the end of the mechanical arm to move. At this time, the slide 130 does not move relative to the slide rail 120, so that the two third detection devices 150 do not detect the movement of the slide 130 relative to the slide rail 120, and no alarm occurs; or, during the contact between the expansion head 310 and the pipe, the slide 130 moves slightly relative to the slide rail 120, then the third detection device 150 with the sensing end pointing to the rear end of the slide rail 120 is separated from the rear end of the slide rail 120, so that the third detection device 150 accurately detects the slight movement of the slide 130 relative to the slide rail 120, while the sensing end of the other third detection device 150 does not detect the movement of the slide 130 relative to the slide rail 120 because it is facing the slide rail 120. In this way, the control system will not recognize that the end of the robot arm drives the frame structure 200 to collide with each other, etc., based only on the movement data detected by the third detection device 150, thereby avoiding false alarms.

[0132] When the expansion head 310 contacts the tube sheet and the end of the robot arm is still pushing the hydraulic expansion gun 300, the spring 170 is severely compressed, so that the front end of the push rod 160 can no longer effectively push the frame structure 200, causing the slide 130 to continue to move relative to the slide rail 120. Not only does the third detection device 150 with the sensing end facing the rear end of the slide rail 120 detect the movement, but when the other third detection device 150 also moves to the rear end of the slide rail 120 and senses, the two third detection devices 150 both detect that the frame structure 200 has moved, and the control system now issues an alarm based on this.

[0133] In this way, the sensing ends of the two third detection devices 150 are directed to different positions of the slide rail 120, so as to accurately detect whether the hydraulic expansion gun 300 on the frame structure 200 has collided, which can not only avoid false alarms, but also can use the two third detection devices 150 to simultaneously sense the movement amount and accurately detect when a collision or excessive thrust of the mechanical arm occurs, thereby preventing further collision or excessive thrust from occurring. In addition, through the interaction of the top plate 110, the two slide rails 120, the two slide seats 130, the two sliding sleeves 140, the two push rods 160 and the two springs 170, the frame structure 200 and the hydraulic expansion gun 300 are prevented from being further pushed up, which also plays a role in protecting the hydraulic expansion gun 300, the tube sheet and the tube.

[0134] See also Figure 1 and Figure 2 Further, the rear end of the protruding structure 351 is provided with an end cover 352, and the end cover 352 wraps the rear end of the protruding structure 351. The rear end of the push rod 320 is threadedly connected with an adjusting nut 353, and the end cover 352 is sandwiched between the adjusting nut 353 and the rear end of the protruding structure 351.

[0135] The telescopic end of the pneumatic vibrator 600 is disposed toward the rear end of the push rod 320 , and the moving end of the first detection device 260 maintains contact with the end cover 352 .

[0136] By utilizing the self-locking function of the adjusting nut 353 and the function that the adjusting nut 353 can move axially along the push rod 320, the elongation of the front end of the push rod 320 relative to the front end of the expansion head 310 can be adjusted according to actual use needs, thereby changing the diameter of the expansion head 310 after radial expansion.

[0137] See also Figure 1 and Figure 2 , further, the elastic member 400 is a rubber rod, and a plurality of the elastic members 400 are respectively connected to the corresponding first outer frame 210 and the second outer frame 220 through a plurality of first bolts, a second bolt is fixed inside the elastic member 400, and the elastic member 400 is connected to the corresponding first inner sleeve 230 and the second inner sleeve 240 through the second bolt;

[0138] The baffle of the second detection device 500 is connected to the corresponding first inner sleeve 230 or the second inner sleeve 240, the sensing end of the second detection device 500 is connected to the corresponding first outer frame 210 or the second outer frame 220, and the baffle of the second detection device 500 is arranged in a one-to-one correspondence with the sensing end.

[0139] The first bolt and the second bolt are used to facilitate fast fixing of the two ends of the rubber rod on the outer frame and the inner sleeve.

[0140] In addition, the baffle of the second detection device 500 and the setting position of the sensing end can ensure accurate detection of the offset of the first inner sleeve 230 and the second inner sleeve 240.

[0141] In addition, this embodiment further provides an industrial robot, which includes the expansion joint device. Since the technical effect achieved by the industrial robot is the same as that of the expansion joint device, the industrial robot will not be further explained.

[0142] In addition, this embodiment further provides a control method, which is used for the industrial robot, and the control method includes:

[0143] Use vision sensors to position tubes on tube sheets;

[0144] Expanding the pipe using a hydraulic expansion gun, and detecting the displacement of a push rod of the hydraulic expansion gun by a first detection device;

[0145] Using the visual sensor to detect in real time whether the outer diameter of the pipe reaches the set expansion diameter;

[0146] When the outer diameter of the pipe reaches the set expansion diameter, the hydraulic expansion gun stops expanding;

[0147] The set pipe is marked, and when the outer diameter of the set pipe reaches the set expansion diameter, the displacement of the push rod of the hydraulic expansion gun does not reach or exceed the set moving distance.

[0148] See also Figures 1 to 4 , further, the industrial robot also includes a pneumatic vibrator, which is arranged at the hydraulic expansion gun;

[0149] When the piston is in contact with the rear end of the hydraulic cylinder, a gap is formed between the front end of the push rod and the front end of the expansion head;

[0150] Before the pipe is expanded by using a hydraulic expansion gun, the method further comprises:

[0151] Based on the length of the pipe detected by the visual sensor, determining whether to flatten the pipe;

[0152] If it is necessary to flatten the pipe, the piston of the hydraulic expansion gun is kept stationary, the pneumatic vibrator is vibrated, and the mechanical arm is controlled to make the expansion head flatten the pipe;

[0153] Expanding the pipe using a hydraulic expansion gun includes:

[0154] Determining whether the tube is a thin-walled tube;

[0155] If the tube is a thin-walled tube, the piston is adapted to move freely in the hydraulic expansion gun and to vibrate the pneumatic vibrator.

[0156] See also Figures 1 to 4 Further, before controlling the hydraulic expansion gun 300 to perform positioning expansion, the method includes:

[0157] Based on the design parameters, determining whether the tube is a thin-walled tube;

[0158] If the tube is a thin-walled tube, only the pneumatic vibrator 600 is vibrated during the positioning expansion process.

[0159] This control method can be used to position and expand tubes with normal wall thickness, and can also position and expand thin-walled tubes that are easily damaged, thereby improving the applicability of the device of the present invention.

[0160] See also Figures 1 to 4 , further, before flat pipe laying, the following steps are included:

[0161] If the number of the pipes marked to be flattened exceeds the set number, all the pipes marked to be flattened are flattened one by one, and then all the pipes are expanded one by one;

[0162] If the number of the pipes marked as needing to be flattened does not exceed the set number, all the pipes are expanded one by one, wherein the pipes marked as needing to be flattened are first flattened and then expanded.

[0163] In this way, when the number of pipes that need to be flattened is too large, centralized flattening operations are adopted to improve the efficiency of flattening operations and avoid affecting the subsequent positioning and expansion operations. When the number of pipes that need to be flattened is small, the flattening process is first performed on the pipes marked to be flattened, and then the positioning and expansion process is performed. Flexible arrangement of the flattening process and the positioning and expansion process is achieved to fully improve the overall efficiency of the positioning and expansion.

[0164] By setting the industrial robot, the industrial robot can comprehensively analyze the preset welding targets and on-site welding conditions of the tube sheet and tube welding according to the design parameters and the images collected by the visual sensor 700, mark the tubes that need to be flattened, and accurately judge whether the expansion head 310 is successfully inserted into the tube in combination with the insertion conditions of the expansion head 310 detected by the second detection devices 500 set at the multiple elastic members 400, and in the case of not accurately inserting into the tube, use the offsets detected by the multiple second detection devices 500 to adjust the position of the end of the robot arm so that the expansion head 310 is lifted or offset to the correct position, so that the axis of the expansion head 310 coincides with the axis of the tube, so that the expansion head 310 is accurately inserted. Then, according to the number of the tubes marked to be flattened, different process arrangements are adopted to realize the fully automatic flattening process and positioning expansion process.

[0165] All steps of the control method provided in this embodiment are as follows:

[0166] S100, storing the input design parameters of the tube sheet and all tubes;

[0167] S200, enabling the visual sensor 700 to identify the detection parameters of all the tubes on the surface of the tube sheet one by one;

[0168] S300, based on the detection parameters, inserting the expansion head 310 of the hydraulic expansion gun 300 into the pipe;

[0169] S400, adjusting the position of the expansion head 310 based on the detection data of the plurality of second detection devices 500, so that the expansion head 310 is inserted into the pipe to a set depth;

[0170] S500, judging whether to flatten the pipes based on the visual recognition system, and recording the number of pipes that need to be flattened;

[0171] S610, if the number of the tubes marked to be flattened exceeds the set number, after performing the tube flattening process on all the tubes marked to be flattened one by one, the positioning expansion process is then performed on all the tubes one by one;

[0172] S620, if the number of the pipes marked as needing to be flattened does not exceed the set number, the positioning and expanding process is performed on all the pipes one by one, wherein the pipe flattening process is first performed on the pipes marked as needing to be flattened, and then the positioning and expanding process is performed;

[0173] S700, performing a pipe flattening operation, keeping the piston of the hydraulic expansion gun stationary, vibrating the pneumatic vibrator, and controlling the mechanical arm to make the expansion head flatten the pipe;

[0174] S800, judging whether the tube is a thin-walled tube based on the design parameters;

[0175] S910, if the tube is a thin-walled tube, when performing the positioning expansion process, the piston is adapted to move freely in the hydraulic expansion gun, and the pneumatic vibrator is vibrated;

[0176] S920, if the tube is not a thin-walled tube, when performing the positioning expansion process, the two solenoid valves are opened to control the hydraulic expansion gun 300 to perform positioning expansion;

[0177] Wherein, the detection parameters at least include: the length of each tube extending out of the tube sheet, the spatial coordinates of each tube and the axial position of each tube.

[0178] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. An expansion joint device, characterized in that: The expansion joint device is used for an industrial robot, and the expansion joint device comprises: A hydraulic expansion gun is arranged at the mechanical arm of the industrial robot. The hydraulic expansion gun drives the push rod of the hydraulic gun to push the expansion head of the hydraulic expansion gun through the piston in the hydraulic cylinder of the hydraulic expansion gun, so that the expansion head diameter of the expansion gun increases. The hydraulic system of the hydraulic expansion gun is connected to the control system of the industrial robot; a first detection device, disposed at the hydraulic expansion gun, for detecting a displacement of the piston or the push rod, and connected to a control system of the industrial robot; and A visual sensor is arranged at the mechanical arm, and is used to identify the position of the pipe in front of the hydraulic expansion gun. The visual sensor is connected to the control system of the industrial robot.

2. The expansion joint device according to claim 1, characterized in that: The expansion joint device further comprises: A pneumatic vibrator is arranged at the hydraulic expansion gun, and is used to drive the hydraulic expansion gun to vibrate.

3. The expansion joint device according to claim 2, characterized in that: The expansion joint device further comprises: A frame structure connected to the mechanical arm of the industrial robot, wherein the hydraulic expansion gun is arranged in the frame structure; A plurality of elastic members are arranged axially around the hydraulic expansion gun, the elastic members connect the frame structure with the hydraulic expansion gun, and the elastic members are used for elastic deformation; and A plurality of second detection devices are arranged at the elastic member in a one-to-one correspondence, the second detection devices are used to detect the elastic deformation of the elastic member, and the plurality of second detection devices are connected to the control system of the industrial robot.

4. The expansion joint device according to claim 3, characterized in that: The frame structure includes a first outer frame, a second outer frame, a first inner sleeve and a second inner sleeve, the ends of the mechanical arm are connected to the first outer frame and the second outer frame respectively, the first inner sleeve is sleeved outside the front end of the hydraulic expansion gun, and the second inner sleeve is sleeved outside the rear end of the hydraulic expansion gun; The first inner sleeve is arranged in the first outer frame, the second inner sleeve is arranged in the second outer frame, the first inner sleeve and the first outer frame are connected through a plurality of corresponding elastic members, and the plurality of elastic members between the first inner sleeve and the first outer frame are arranged around the first inner sleeve, The second inner sleeve is connected to the second outer frame via a plurality of corresponding elastic members, and the plurality of elastic members between the second inner sleeve and the second outer frame are arranged around the second inner sleeve.

5. The expansion joint device according to claim 4, characterized in that: The frame structure further comprises a first fixing seat, the first fixing seat is detachably connected to the second inner sleeve, and the pneumatic vibrator is detachably connected to the first fixing seat; The push rod is connected to the piston, and the front end of the push rod extends out of the hydraulic cylinder and is inserted into the expansion head; When the piston is in contact with the rear end of the hydraulic cylinder, a gap is formed between the front end of the push rod and the front end of the expansion head, the rear end of the push rod extends out of the rear end of the hydraulic cylinder, and the vibrating end of the pneumatic vibrator is in contact with the rear end of the push rod, and the pneumatic vibrator is used to push the push rod to vibrate forward; The hydraulic system of the hydraulic expansion gun is adapted to allow the piston to move freely within the hydraulic cylinder.

6. The expansion joint device according to claim 5, characterized in that: The rear end of the piston is provided with a protruding structure, the rear end of the protruding structure extends out of the rear end of the hydraulic cylinder, the push rod is inserted into the protruding structure and the piston, and the rear end of the push rod extends out of the rear end of the protruding structure; The first fixing seat is a long strip plate-like member bent around its wide side into a U-shape, the protruding structure and the rear end of the push rod are placed in the hollow of the first fixing seat, and the two ends of the U-shape of the first fixing seat are detachably connected to the second inner sleeve respectively. The pneumatic vibrator and the first detection device can be detachably arranged outside the first fixing seat. The first detection device is connected to the protruding structure, and the first detection device is used to detect the displacement of the protruding structure.

7. The expansion joint device according to claim 6, characterized in that: The expansion joint device further comprises a second fixing seat, wherein the second fixing seat is used to replace the first fixing seat. The pneumatic vibrator and the first detection device can be detachably arranged outside the second fixing seat, and the second fixing seat is detachably connected to the second outer frame. The first detection device is a self-resetting displacement sensor, and the moving end of the first detection device passes through the second fixing seat and is connected to the rear end of the protruding structure; The expansion joint device also includes a top plate, two slide rails, two slide seats, two sliding sleeves, two third detection devices, two push rods and two springs. The top plate is connected to the end of the mechanical arm, and the third detection device is a proximity switch; The two slide rails are arranged parallel to each other at the bottom of the top plate, each slide seat is clamped on one of the slide rails, and the slide seat is used to reciprocate along the slide rails. The bottom of the slide seat is connected to the top of the frame structure. The sliding sleeve is arranged at the bottom of the top plate, each of the top rods is sleeved in one of the sliding sleeves, each of the springs is sleeved outside one of the top rods, a limiting protrusion is arranged at the front end of the top rod, the limiting protrusion is used to prevent the spring from being separated from the top rod, the spring is arranged between the limiting protrusion and the sliding sleeve, the spring is in an extended state, and the front end of the top rod supports the frame structure; The two third detection devices are arranged at the frame structure, the sensing end of one of the third detection devices is arranged toward the rear end of the slide rail, and the sensing end of the other third detection device is arranged toward the slide rail.

8. An industrial robot, characterized in that: The industrial robot comprises the expansion device according to any one of claims 1 to 7.

9. A control method, characterized in that: The control method is used for the industrial robot according to claim 8, and the control method comprises: Use vision sensors to position tubes on tube sheets; Expanding the pipe using a hydraulic expansion gun, and detecting the displacement of a push rod of the hydraulic expansion gun by a first detection device; Using the visual sensor to detect in real time whether the outer diameter of the pipe reaches the set expansion diameter; When the outer diameter of the pipe reaches the set expansion diameter, the hydraulic expansion gun stops expanding; The set pipe is marked, and when the outer diameter of the set pipe reaches the set expansion diameter, the displacement of the push rod of the hydraulic expansion gun does not reach or exceed the set moving distance.

10. The control method according to claim 9, characterized in that: The industrial robot further comprises a pneumatic vibrator, which is arranged at the hydraulic expansion gun, and when the piston is in contact with the rear end of the hydraulic cylinder, a gap is formed between the front end of the push rod and the front end of the expansion head; Before the pipe is expanded by using a hydraulic expansion gun, the method further comprises: Based on the length of the pipe detected by the visual sensor, determining whether to flatten the pipe; If it is necessary to flatten the pipe, the piston of the hydraulic expansion gun is kept stationary, the pneumatic vibrator is vibrated, and the mechanical arm is controlled to make the expansion head flatten the pipe; Expanding the pipe using a hydraulic expansion gun includes: Determining whether the tube is a thin-walled tube; If the tube is a thin-walled tube, the piston is adapted to move freely in the hydraulic expansion gun and to vibrate the pneumatic vibrator.

Images