Nut tightening device and method

Abstract

The invention provides a nut tightening device and method, the device comprises a driving assembly, the driving assembly is connected with a tightening assembly, the tightening assembly comprises a suction cup, and the side, away from the driving assembly, of the suction cup is connected with a first sleeve. A limiting assembly is arranged close to the driving assembly and connected with the tightening assembly. The driving assembly drives the tightening assembly to move upwards so as to extrude the limiting assembly. And the limiting assembly gradually recovers deformation to drive the tightening assembly to move downwards and rotate, so that the nut in the first sleeve is tightened on the machining position. And the driving assembly drives the tightening assembly to rotate, meanwhile, the limiting assembly starts to restore deformation, the tightening assembly moves downwards while rotating, and therefore the nut in the first sleeve is tightened to the machining position. The downward elastic force is provided by the limiting assembly, so that the first sleeve forms buffering in the process of being in butt joint with the machining position, the quality problem caused by serious abrasion between the nut and the machining position is avoided, and the production efficiency and the automation level are greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of air conditioner assembly, and in particular to a nut tightening device and method. Background Art

[0002] The process of assembling the valve core nut of the stop valve assembly of the air-conditioning outdoor unit currently relies on manual assembly of the air-conditioning assembly nuts. Each time the materials are boxed and the nuts are installed, the large and small nut models need to be manually distinguished. Employees' repetitive actions may lead to quality risks such as missing nuts and improper assembly of nuts, low operating efficiency and high labor intensity.

[0003] Therefore, a nut tightening device that can reduce the labor intensity of employees and has high production efficiency is needed. Summary of the invention

[0004] In order to overcome the problems existing in the related art, an object of the present invention is to provide a nut tightening device and method, which reduces the labor intensity of employees and has high production efficiency.

[0005] A nut tightening device comprises a driving assembly, wherein the driving assembly is connected to a tightening assembly, the tightening assembly comprises a suction cup, and a first sleeve is connected to the side of the suction cup away from the driving assembly; a limiting assembly is arranged near the driving assembly, and the limiting assembly is connected to the tightening assembly; the driving assembly drives the tightening assembly to move upward to squeeze the limiting assembly; the limiting assembly gradually recovers its deformation to drive the tightening assembly to move downward and rotate to tighten the nut in the first sleeve to the processing position.

[0006] In a preferred technical solution of the present invention, the limiting assembly includes a first buffer plate and a second buffer plate, and the second buffer plate is located below the first buffer plate.

[0007] In a preferred technical solution of the present invention, a sliding shaft is connected between the first buffer plate and the second buffer plate, and the sliding shaft is arranged along the height direction.

[0008] In a preferred technical solution of the present invention, an elastic member is sleeved on the sliding shaft, the first end of the elastic member is connected to the first buffer plate, the second end of the elastic member is connected to a second sleeve, the second sleeve is connected to the second buffer plate, and the second sleeve squeezes the elastic member when moving upward along the sliding shaft.

[0009] In a preferred technical solution of the present invention, a mounting block is further provided between the second sleeve and the second buffer plate, the mounting block is connected to the driving assembly, and the driving assembly is used to drive the mounting block to move upward to push the second sleeve to move upward.

[0010] In a preferred technical solution of the present invention, the driving assembly includes a servo motor, an output shaft of the servo motor is connected to the tightening assembly, and the output shaft of the servo motor is used to drive the tightening assembly to rotate.

[0011] In a preferred technical solution of the present invention, a side of the mounting block away from the second sleeve is connected to a shaft seat, and the tightening assembly is mounted on the shaft seat.

[0012] In a preferred technical solution of the present invention, the tightening assembly further includes a connecting rod, a first end of the connecting rod is connected to the output shaft of the servo motor, and a second end of the connecting rod is connected to the suction cup.

[0013] The present invention further provides a nut tightening method, based on any one of the above nut tightening devices, the method comprising:

[0014] Move the nut tightening device to the feeding position, and control the suction cup to absorb the nut into the first sleeve;

[0015] Move the nut tightening device to the processing position, and align the tightening assembly with the stop valve stud;

[0016] The tightening assembly moves downward, driving the nut to move downward;

[0017] The driving assembly drives the nut to rotate so as to tighten the nut onto the stop valve stud.

[0018] In a preferred technical solution of the present invention, the tightening assembly moves downward, driving the nut to move downward, including:

[0019] Lift the mounting block upward;

[0020] The second sleeve squeezes the elastic member so that the elastic member is compressed;

[0021] The elastic member gradually recovers its deformation, driving the nut to move downward.

[0022] In a preferred technical solution of the present invention, the driving assembly drives the nut to rotate so as to tighten the nut on the stop valve stud, comprising:

[0023] Get the current torque of the servo motor;

[0024] If the current torque is less than the starting torque, maintaining the starting torque;

[0025] If the current torque is greater than or equal to the starting torque and less than the target torque, the torque is increased linearly;

[0026] If the current torque is greater than or equal to the target torque, the servo motor is controlled to stop running.

[0027] The beneficial effects of the present invention are:

[0028] The present invention provides a nut tightening device, comprising a driving component, wherein the driving component is connected to a tightening component, wherein the tightening component comprises a suction cup, and a first sleeve is connected to the side of the suction cup away from the driving component; a limiting component is arranged near the driving component, and the limiting component is connected to the tightening component; the driving component drives the tightening component to move upward to squeeze the limiting component; the limiting component gradually recovers its deformation to drive the tightening component to move downward and rotate to tighten the nut in the first sleeve to a processing position. The driving component drives the tightening component to absorb the nut into the first sleeve through the suction cup, and then the driving component drives the tightening component to move above the processing position to align the first sleeve with the processing position. In the process of aligning the first sleeve with the processing position, the tightening component is lifted upward, and the tightening component applies an upward force to the limiting component to squeeze the limiting component, so that the limiting component is compressed and deformed. The driving component drives the tightening component to rotate, thereby driving the adsorbed nut to rotate. At the same time, the limiting component begins to restore its deformation, so that the tightening component moves downward while rotating, thereby tightening the nut in the first sleeve to the processing position. In the process of the limiting component gradually restoring its deformation, the first sleeve forms a buffer during the docking process of the processing position, avoiding serious wear between the nut and the processing position and causing quality problems. By driving the tightening component to move to tighten the nut to the processing position, the tightening component can automatically tighten the nut, which not only reduces the labor intensity of employees, but also greatly improves production efficiency and automation level. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a side view of the nut tightening device of the present invention;

[0030] Figure 2 It is a structural schematic diagram of a nut tightening device of the present invention;

[0031] Figure 3 is a front view of the nut tightening device of the present invention;

[0032] Figure 4 is a top view of the nut tightening device of the present invention;

[0033] Figure 5 is a flow chart of a nut tightening method of the present invention;

[0034] Figure 6 It is a flow chart of driving the nut to move downward according to the present invention.

[0035] Figure numerals: 1. suction cup; 2. first sleeve; 3. first buffer plate; 4. second buffer plate; 5. sliding shaft; 6. elastic member; 7. mounting block; 8. second sleeve; 9. servo motor; 10. shaft seat; 11. connecting rod; 12. driving assembly; 13. tightening assembly; 14. limiting assembly; 15. robot mounting seat; 16. locking back plate; 17. support plate. DETAILED DESCRIPTION

[0036] The preferred embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0037] Example 1

[0038] like Figure 1-Figure 4 As shown, this embodiment provides a nut tightening device, including a driving component 12, wherein the driving component 12 is connected to a tightening component 13, and the tightening component 13 includes a suction cup 1, and the side of the suction cup 1 away from the driving component 12 is connected to a first sleeve 2; a limiting component 14 is arranged near the driving component 12, and the limiting component 14 is connected to the tightening component 13; the driving component 12 drives the tightening component 13 to move upward to squeeze the limiting component 14; the limiting component 14 gradually restores its deformation to drive the tightening component 13 to move downward and rotate to tighten the nut in the first sleeve 2 to the processing position.

[0039] The nut that needs to be tightened in this embodiment is a nut used for an air conditioner, and the nut is tightened on a stop valve stud of the air conditioner.

[0040] The tightening assembly 13 includes a suction cup 1 and a first sleeve 2. The suction cup 1 is nested in the first sleeve 2. The radial dimension of the first sleeve 2 is greater than or equal to the width of the nut. The suction cup 1 can directly absorb the nut in the first sleeve 2. Preferably, the first sleeve 2 and the suction cup 1 are detachably connected. By designing first sleeves 2 of different sizes to adapt to nuts of different sizes, and then replacing the first sleeve 2 of the corresponding size according to the size of the nut, the tightening assembly 13 can tighten nuts of different sizes on the processing position.

[0041] The nut tightening device may include multiple tightening assemblies 13, so that the nut tightening device can tighten multiple nuts at the same time. The sizes of the first sleeves 2 of the multiple tightening assemblies 13 can be the same or different, so as to tighten nuts of the same or different sizes. In this embodiment, the nut tightening device includes two parallel tightening assemblies 13 as an example. The first sleeves 2 of the two tightening assemblies 13 are respectively adapted to nuts of two different sizes. The first sleeve 2 of the first tightening assembly 13 is adapted to the first nut, and the first sleeve 2 of the second tightening assembly 13 is adapted to the second nut. The two tightening assemblies 13 are respectively connected to the driving assemblies 12. The first driving assembly 12 drives the suction cup 1 of the first tightening assembly 13 to adsorb the first nut in the first sleeve 2, and the second driving assembly 12 drives the suction cup 1 of the second tightening assembly 13 to adsorb the second nut in the first sleeve 2.

[0042] The driving assembly 12 provides a power source for the tightening assembly 13. The driving assembly 12 drives the tightening assembly 13 to move in the height direction and can also drive the tightening assembly 13 to rotate, so that the tightening assembly 13 rotates while moving up and down to tighten the nut. The limiting assembly 14 limits the distance that the tightening assembly 13 moves in the height direction, so that the tightening assembly 13 moves up and down within a certain height range, so that the tightening assembly 13 can form a buffer when tightening the nut, avoiding serious wear of the processing position and the nut, resulting in a decrease in the assembly quality of the nut.

[0043] The present embodiment provides a nut tightening device, comprising a driving assembly 12, wherein the driving assembly 12 is connected to a tightening assembly 13, wherein the tightening assembly 13 comprises a suction cup 1, wherein a first sleeve 2 is connected to the side of the suction cup 1 away from the driving assembly 12; a limiting assembly 14 is arranged near the driving assembly 12, wherein the limiting assembly 14 is connected to the tightening assembly 13; and the driving assembly 12 drives the tightening assembly 13 to move upward to squeeze the limiting assembly 14. In the process of the limiting assembly 14 gradually recovering its deformation, the limiting assembly 14 applies a downward elastic force to the tightening assembly 13 to drive the tightening assembly 13 to move downward, and at the same time, the driving assembly 12 drives the tightening assembly 13 to rotate to tighten the nut in the first sleeve 2 to the processing position. Before tightening the nut in the processing position, the process of adsorbing the nut is also included: aligning the tightening component 13 with the nut placement position, the driving component 12 drives the tightening component 13 to adsorb the nut into the first sleeve 2 through the suction cup 1, and then the driving component 12 drives the tightening component 13 to move above the processing position so that the first sleeve 2 is aligned with the processing position. Lift the tightening component 13 upward, and the tightening component 13 applies an upward force to the limiting component 14 to squeeze the limiting component 14, so that the limiting component 14 is compressed and deformed. The driving component 12 drives the tightening component 13 to rotate to drive the adsorbed nut to rotate, and at the same time, the limiting component 14 begins to restore the deformation, so that the tightening component 13 moves downward while rotating, thereby tightening the nut in the first sleeve 2 to the processing position. In the process of the limiting component 14 gradually restoring the deformation, the first sleeve 2 forms a buffer in the process of docking the processing position, avoiding serious wear between the nut and the processing position and causing quality problems. By driving the tightening assembly 13 to move and tighten the nut at the processing position through the driving assembly 12, the tightening assembly 13 can automatically tighten the nut, which not only reduces the labor intensity of employees, but also greatly improves production efficiency and automation level.

[0044] Example 2

[0045] like Figure 1-Figure 4 As shown, this embodiment provides a nut tightening device, including a driving component 12, wherein the driving component 12 is connected to a tightening component 13, and the tightening component 13 includes a suction cup 1, and the side of the suction cup 1 away from the driving component 12 is connected to a first sleeve 2; a limiting component 14 is arranged near the driving component 12, and the limiting component 14 is connected to the tightening component 13; the driving component 12 drives the tightening component 13 to move upward to squeeze the limiting component 14; the limiting component 14 gradually restores its deformation to drive the tightening component 13 to move downward and rotate to tighten the nut in the first sleeve 2 to the processing position.

[0046] The limiting assembly 14 includes a first buffer plate 3 and a second buffer plate 4 , and the second buffer plate 4 is located below the first buffer plate 3 .

[0047] A sliding shaft 5 is connected between the first buffer plate 3 and the second buffer plate 4 , and the sliding shaft 5 is arranged along the height direction.

[0048] An elastic member 6 is sleeved on the sliding shaft 5, a first end of the elastic member 6 is connected to the first buffer plate 3, a second end of the elastic member 6 is connected to a second sleeve 8, the second sleeve 8 is connected to the second buffer plate 4, and the second sleeve 8 squeezes the elastic member 6 when moving upward along the sliding shaft 5.

[0049] A locking back plate 16 is also connected between the first buffer plate 3 and the second buffer plate 4. The locking back plate 16 is fixed on the support plate 17. The side of the support plate 17 away from the locking back plate 16 is connected to the robot mounting seat 15 and the reinforcing ribs. The reinforcing ribs are located below the robot mounting seat 15 and connected to the robot mounting seat 15. The setting of the reinforcing ribs makes the connection between the robot mounting seat 15 and the support plate 17 more stable and firm. The robot mounting seat 15 is used to fix the nut tightening device on the robot, and the nut tightening device is controlled by the robot.

[0050] Preferably, there are two sliding shafts 5 connected between the first buffer plate 3 and the second buffer plate 4, and the two sliding shafts 5 are respectively sleeved with elastic members 6 and second sleeves 8. When the driving assembly 12 drives the tightening assembly 13 to move upward, the two second sleeves 8 squeeze the two elastic members 6 while moving upward along the sliding shaft 5, and the two elastic members 6 are deformed at the same time. In the process of the two elastic members 6 recovering their deformation at the same time, the driving assembly 12 drives the tightening assembly 13 to move downward and rotate, and in this process, the nut in the first sleeve 2 is tightened at the processing position. When subjected to an upward thrust, the thrust is evenly distributed to the two second sleeves 8. When the second sleeve 8 squeezes the elastic member 6, the elastic member 6 will not be unable to recover its deformation due to excessive squeezing, which greatly extends the service life of the elastic member 6.

[0051] The limit assembly 14 of this embodiment includes a first buffer plate 3 and a second buffer plate 4, and the second buffer plate 4 is located below the first buffer plate 3. A sliding shaft 5 is connected between the first buffer plate 3 and the second buffer plate 4, and the sliding shaft 5 is arranged along the height direction. An elastic member 6 is sleeved on the sliding shaft 5, and the first end of the elastic member 6 is connected to the first buffer plate 3, and the second end of the elastic member 6 is connected to the second sleeve 8, and the second sleeve 8 is connected to the second buffer plate 4. When the second sleeve 8 moves upward along the sliding shaft 5, it squeezes the elastic member 6. When the driving assembly 12 drives the tightening assembly 13 to move upward, the first end of the elastic member 6 is fixed on the first buffer plate 3 and does not move, and the second end of the elastic member 6 is connected to the second sleeve 8. The second sleeve 8 slides upward along the sliding shaft 5 to squeeze the elastic member 6, and the second end of the elastic member 6 moves upward along the sliding shaft 5 and approaches the first buffer plate 3. During the process of elastic member 6 restoring its deformation, the first end of elastic member 6 is fixed to the first buffer plate 3 and does not move, while the second end of elastic member 6 moves downward along the sliding shaft 5 to push the second sleeve 8 close to the second buffer plate 4. At this time, the driving assembly 12 drives the tightening assembly 13 to move downward and rotate, and tightens the nut in the first sleeve 2 to the processing position. In the above process, the elastic member 6 plays a buffering role in the process of driving assembly 12 driving the tightening assembly 13 to tighten the nut, so that when the nut is tightened to the processing position, the nut and the processing position will not be affected by excessive wear and tear, so that the tightening quality of the nut by the nut tightening device is guaranteed.

[0052] Example 3

[0053] like Figure 1-Figure 4 As shown, this embodiment provides a nut tightening device, including a driving component 12, wherein the driving component 12 is connected to a tightening component 13, and the tightening component 13 includes a suction cup 1, and the side of the suction cup 1 away from the driving component 12 is connected to a first sleeve 2; a limiting component 14 is arranged near the driving component 12, and the limiting component 14 is connected to the tightening component 13; the driving component 12 drives the tightening component 13 to move upward to squeeze the limiting component 14; the limiting component 14 gradually restores its deformation to drive the tightening component 13 to move downward and rotate to tighten the nut in the first sleeve 2 to the processing position.

[0054] The limiting assembly 14 includes a first buffer plate 3 and a second buffer plate 4 , and the second buffer plate 4 is located below the first buffer plate 3 .

[0055] A sliding shaft 5 is connected between the first buffer plate 3 and the second buffer plate 4 , and the sliding shaft 5 is arranged along the height direction.

[0056] An elastic member 6 is sleeved on the sliding shaft 5, a first end of the elastic member 6 is connected to the first buffer plate 3, a second end of the elastic member 6 is connected to a second sleeve 8, the second sleeve 8 is connected to the second buffer plate 4, and the second sleeve 8 squeezes the elastic member 6 when moving upward along the sliding shaft 5.

[0057] A mounting block 7 is further provided between the second sleeve 8 and the second buffer plate 4 , and the mounting block 7 is connected with the driving assembly 12 . The driving assembly 12 is used for driving the mounting block 7 to move upwards, so as to push the second sleeve 8 to move upwards.

[0058] The driving assembly 12 includes a servo motor 9 , the output shaft of the servo motor 9 is connected to the tightening assembly 13 , and the output shaft of the servo motor 9 is used to drive the tightening assembly 13 to rotate.

[0059] When the driving component 12 drives the tightening component 13 to move upward, the driving component 12 drives the mounting block 7 to move upward, the mounting block 7 pushes the second sleeve 8 to move upward, the second sleeve 8 squeezes the elastic member 6 upward along the sliding shaft 5, and the elastic member 6 is compressed upward to deform. The elastic member 6 recovers its deformation under the action of elastic force, and pushes the second sleeve 8 to move downward along the sliding shaft 5 to push the mounting block 7 to move downward. At this time, the driving component 12 drives the tightening component 13 to move downward. Since the output shaft of the servo motor 9 is connected to the tightening component 13, during the downward movement of the tightening component 13, the output shaft of the servo motor 9 drives the tightening component 13 to rotate, so that the driving component 12 rotates while driving the tightening component 13 to move downward. During this process, the tightening component 13 tightens the nut at the processing position.

[0060] Preferably, the servo motor 9 is a 400W locking motor, which provides rotational power for the tightening assembly 13, so that the servo motor 9 can tighten the nut on the processing position more quickly and accurately when driving the tightening assembly 13 to rotate. The servo motor 9 is connected to a control system, and the control system includes a control program. The control system sets the thread pitch, the number of thread turns, the set distance per rotation angle of the nut, and the torque value range of the servo motor 9 in advance according to the program. The torque of the servo motor 9 is controlled by the control system to ensure that the output torque of the servo motor 9 is within the set range, so as to achieve the controllability of the nut assembly speed and tightening torque, and avoid quality problems such as untightening and thread slippage caused by unqualified manual tightening torque.

[0061] In this embodiment, a mounting block 7 is further arranged between the second sleeve 8 and the second buffer plate 4. The mounting block 7 is connected with the driving assembly 12. The driving assembly 12 is used to drive the mounting block 7 to move upward to push the second sleeve 8 to move upward. The driving assembly 12 includes a servo motor 9. The output shaft of the servo motor 9 is connected to the tightening assembly 13. The output shaft of the servo motor 9 is used to drive the tightening assembly 13 to rotate. When the nut tightening device tightens the nut, the driving assembly 12 drives the first sleeve 2 of the tightening assembly 13 to align with the processing position. In the process of aligning the processing position, the driving assembly 12 drives the mounting block 7 to move upward, and the mounting block 7 pushes the second sleeve 8 to move upward. The second sleeve 8 squeezes the elastic member 6 along the direction of the sliding shaft 5, so that the elastic member 6 is deformed. The elastic member 6 then slowly recovers its deformation. In the process of the elastic member 6 recovering its deformation, the second sleeve 8 is pushed downward by the elastic member 6. The second sleeve 8 pushes the mounting block 7 downward, and the mounting block 7 drives the driving assembly 12 to move downward to drive the tightening assembly 13 to move downward. During the downward movement of the tightening assembly 13, the output shaft of the servo motor 9 drives the tightening assembly 13 to move downward and rotates at the same time, so that the nut is tightened on the processing position during the downward rotation of the tightening assembly 13. In this process, the mounting block 7 not only plays a role in connecting and fixing between the limit assembly 14 and the driving assembly 12, but also drives the mounting block 7 to squeeze the limit assembly 14 upward when the driving assembly 12 moves upward. When the limit assembly 14 recovers its deformation, the limit assembly 14 pushes the mounting block 7 to move downward to drive the driving assembly 12 to move downward. In the above process, the servo motor 9 is used in combination with a control system, so that the servo motor 9 can tighten the nut on the processing position more quickly and accurately when driving the tightening assembly 13 to rotate, realizing the automatic tightening of the nut by the nut tightening device, which not only reduces the labor intensity of employees, but also greatly improves the production efficiency of nut tightening.

[0062] Example 4

[0063] like Figure 1-Figure 4 As shown, this embodiment provides a nut tightening device, including a driving component 12, wherein the driving component 12 is connected to a tightening component 13, and the tightening component 13 includes a suction cup 1, and the side of the suction cup 1 away from the driving component 12 is connected to a first sleeve 2; a limiting component 14 is arranged near the driving component 12, and the limiting component 14 is connected to the tightening component 13; the driving component 12 drives the tightening component 13 to move upward to squeeze the limiting component 14; the limiting component 14 gradually restores its deformation to drive the tightening component 13 to move downward and rotate to tighten the nut in the first sleeve 2 to the processing position.

[0064] The limiting assembly 14 includes a first buffer plate 3 and a second buffer plate 4 , and the second buffer plate 4 is located below the first buffer plate 3 .

[0065] A sliding shaft 5 is connected between the first buffer plate 3 and the second buffer plate 4 , and the sliding shaft 5 is arranged along the height direction.

[0066] An elastic member 6 is sleeved on the sliding shaft 5, a first end of the elastic member 6 is connected to the first buffer plate 3, a second end of the elastic member 6 is connected to a second sleeve 8, the second sleeve 8 is connected to the second buffer plate 4, and the second sleeve 8 squeezes the elastic member 6 when moving upward along the sliding shaft 5.

[0067] A mounting block 7 is further provided between the second sleeve 8 and the second buffer plate 4 , and the mounting block 7 is connected with the driving assembly 12 . The driving assembly 12 is used for driving the mounting block 7 to move upwards, so as to push the second sleeve 8 to move upwards.

[0068] A shaft seat 10 is connected to a side of the mounting block 7 away from the second sleeve 8 , and the tightening assembly 13 is mounted on the shaft seat 10 .

[0069] The tightening assembly 13 further includes a connecting rod 11 , a first end of the connecting rod 11 is connected to the output shaft of the servo motor 9 , and a second end of the connecting rod 11 is connected to the suction cup 1 .

[0070] The shaft seat 10 is used to fix the tightening assembly 13 so that the tightening assembly 13 is connected to the driving assembly 12. The shaft seat 10 consists of two parts, the first part is L-shaped and arranged in the height direction, and is used to fix the tightening assembly 13 in the height direction. The second part is C-shaped and arranged in the horizontal direction, and is used to fix the tightening assembly 13 in the horizontal direction. The first part and the second part of the shaft seat 10 can be detachably connected or integrally formed, which is not limited here.

[0071] A through hole is formed on one side of the first sleeve 2 near the shaft seat 10, and the second end of the connecting rod 11 is adapted to the through hole. The second end of the connecting rod 11 is inserted into the through hole and connected to the suction cup 1. When the servo motor 9 is working, the output shaft of the servo motor 9 rotates, driving the connecting rod 11 to rotate, and the connecting rod 11 drives the first sleeve 2 and the suction cup 1 to rotate.

[0072] Preferably, a locking mechanism is provided on the connecting rod 11, and the connecting rod 11 can be extended and retracted up and down, so that the length of the connecting rod 11 is adjustable. The length of the connecting rod 11 is adjusted according to the relative position of the stop valve stud and the nut tightening device, and then the locking mechanism is used to lock the connecting rod 11 to keep the length of the connecting rod 11 unchanged until the next time the nut is tightened, the locking mechanism is released, and the length of the connecting rod 11 is adjusted.

[0073] The side of the mounting block 7 of this embodiment away from the second sleeve 8 is connected to an axle seat 10, and the tightening assembly 13 is installed on the axle seat 10. The tightening assembly 13 also includes a connecting rod 11, a first end of the connecting rod 11 is connected to the output shaft of the servo motor 9, and a second end of the connecting rod 11 is connected to the suction cup 1. The axle seat 10 is composed of two parts, the first part is L-shaped and arranged in the height direction, and is used to fix the tightening assembly 13 in the height direction. The second part is C-shaped and arranged in the horizontal direction, and is used to fix the tightening assembly 13 in the horizontal direction. The first part and the second part of the axle seat 10 can be detachably connected or integrally formed.

[0074] Example 5

[0075] like Figure 5-Figure 6 As shown, this embodiment provides a nut tightening method, based on the nut tightening device described in any one of Embodiments 1 to 4, the method comprises:

[0076] S1: Move the nut tightening device to the feeding position, and control the suction cup to absorb the nut into the first sleeve.

[0077] S2: Move the nut tightening device to the processing position and align the tightening assembly with the stop valve stud.

[0078] S3: The tightening assembly moves downward, driving the nut to move downward.

[0079] S4: The driving assembly drives the nut to rotate so as to tighten the nut onto the stop valve stud.

[0080] The side of the support plate 17 away from the locking back plate 16 is connected with a robot mounting seat 15 and a reinforcing rib, and the nut tightening device is integrally mounted on the robot using the robot mounting seat 15. A CCD visual camera system is set on the robot arm or other positions of the robot, and the CCD visual camera system is used to identify the nut placement position and processing position in the processing scene, and navigate the robot.

[0081] The robot moves to the nut placement position, the air pipe of the air pressure control system is connected to the first sleeve 2, and the air pressure control system generates vacuum negative pressure at the suction cup 1. Under the action of the suction cup 1, the nut at the nut placement position is adsorbed into the first sleeve 2, so as to quickly absorb the nut and prevent the nut from falling. This embodiment takes the absorption of a larger nut and a smaller nut in sequence as an example.

[0082] The robot moves to the processing position and uses the CCD visual camera system to align the first sleeve 2 with the stop valve stud on the processing position. The robot's mechanical arm lifts the tightening assembly 13 upward, so that the tightening assembly 13 squeezes the limit assembly 14, causing the elastic member 6 of the limit assembly 14 to produce compression deformation. In the process of the elastic member 6 gradually recovering its deformation, the elastic force of the elastic member 6 rebounds and provides a downward force to the tightening assembly 13, driving the first sleeve 2, the suction cup 1 and the nut to move downward, while the servo motor 9 of the drive assembly 12 drives the first sleeve 2 to rotate, so as to tighten the nut on the stop valve stud.

[0083] The tightening assembly moves downward, driving the nut to move downward, including:

[0084] S31: Lift the mounting block upward.

[0085] S32: The second sleeve squeezes the elastic member to compress the elastic member.

[0086] S33: The elastic member gradually recovers its deformation, driving the nut to move downward.

[0087] The mounting block 7 is lifted upward, and the mounting block 7 presses the second sleeve 8 upward, and the second sleeve 8 presses the elastic member 6 upward, so that the elastic member 6 is elastically deformed and in a compressed state. The elastic member 6 in the compressed state gradually recovers its deformation until the elastic member 6 is in a naturally extended state. In the process of the elastic member 6 gradually recovering its deformation, the elastic member 6 provides a downward force to the first sleeve 2, the suction cup 1 and the nut, driving the nut to move downward.

[0088] The driving assembly drives the nut to rotate so as to tighten the nut on the stop valve stud, comprising:

[0089] S41: Get the current torque of the servo motor.

[0090] S42: If the current torque is less than the starting torque, the starting torque is maintained.

[0091] S43: If the current torque is greater than or equal to the starting torque and less than the target torque, the torque is increased linearly.

[0092] S44: If the current torque is greater than or equal to the target torque, the servo motor is controlled to stop running.

[0093] Before the servo motor 9 is started, the parameters of the servo motor 9 are preset, and the parameters of the servo motor 9 include the pitch of the thread, the number of thread turns, the preset distance of the nut per rotation of the preset angle, the torque range and the compensation coefficient. After the servo motor 9 is started, the current of the servo motor 9 is adjusted to adjust the torque, and whether the nut is tightened in place is judged according to the torque.

[0094] As an example, the tightening torque of the plastic nut is 2.5±0.5 NM, the program sets the starting torque of the servo motor 9 to 1 N.m, the tightening torque to 16.5 Nm, and the compensation coefficient to 75%.

[0095] The output torque of the motor is monitored and displayed in real time through the servo driver, PLC and touch screen to ensure that the output torque of the motor is within the set range. Torque (T) = torque constant (Kt) × motor current (L) / motor efficiency; where the torque constant (Kt) represents the torque generated by the motor per ampere (A) current, the motor current (L) is the current value when the motor is working, and the motor efficiency is the energy conversion efficiency of the servo motor 9.

[0096] Torque control logic:

[0097] If the current torque is less than the starting torque, the starting torque state is maintained.

[0098] If the starting torque ≤ current torque < target torque, the torque is increased linearly.

[0099] If the current torque ≥ the target torque, stop the motor and record the result.

[0100] Preferably, a compensation coefficient is used to adjust the tightening torque, and the torque output by the servo motor 9 is adjusted based on the target value so that the actual output torque is 75% of the target torque. The calculation formula of the actual torque is as follows:

[0101] Actual torque = target torque × compensation coefficient;

[0102] The target torque is compensated by using a compensation coefficient in order to compensate for the mechanical errors and wear that may occur during the tightening process, making the torque control more precise, thereby improving the tightening quality and enhancing the durability of the nut tightening device.

[0103] This embodiment provides a nut tightening method, including moving the nut tightening device to the feeding position, controlling the suction cup 1 to absorb the nut into the first sleeve 2. The nut tightening device is moved to the processing position, and the tightening assembly 13 is aligned with the stop valve stud. The tightening assembly 13 moves downward, driving the nut to move downward. The driving assembly 12 drives the nut to rotate so as to tighten the nut on the stop valve stud. The robot moves to the processing position, and uses the CCD visual camera system to align the first sleeve 2 with the stop valve stud on the processing position. The robot's mechanical arm lifts the tightening assembly 13 upward, so that the tightening assembly 13 squeezes the limiting assembly 14, so that the elastic member 6 of the limiting assembly 14 produces compression deformation. In the process of the elastic member 6 gradually recovering the deformation, the elastic force of the elastic member 6 rebounding provides a downward force to the tightening assembly 13, driving the first sleeve 2, the suction cup 1 and the nut to move downward, and at the same time, the servo motor 9 of the driving assembly 12 drives the first sleeve 2 to rotate to tighten the nut on the stop valve stud. The target torque can also be compensated by using a compensation coefficient in order to compensate for mechanical errors and wear that may occur during the tightening process, making the torque control more precise, thereby improving the tightening quality and enhancing the durability of the nut tightening device.

[0104] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the application. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a restriction. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in the subsequent accompanying drawings.

[0105] It should be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would then be positioned "below" or "below" the other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used herein should be interpreted accordingly.

[0106] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0107] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A nut tightening device, characterized in that: It includes a driving component, which is connected to a tightening component, and the tightening component includes a suction cup, and a first sleeve is connected to the side of the suction cup away from the driving component; a limiting component is arranged near the driving component, and the limiting component is connected to the tightening component; the driving component drives the tightening component to move upward to squeeze the limiting component; the limiting component gradually restores its deformation to drive the tightening component to move downward and rotate to tighten the nut in the first sleeve to the processing position.

2. The nut tightening device according to claim 1, characterized in that: The limiting assembly includes a first buffer plate and a second buffer plate, wherein the second buffer plate is located below the first buffer plate.

3. The nut tightening device according to claim 2, characterized in that: A sliding shaft is connected between the first buffer plate and the second buffer plate, and the sliding shaft is arranged along the height direction.

4. The nut tightening device according to claim 3, characterized in that: An elastic member is sleeved on the sliding shaft, a first end of the elastic member is connected to the first buffer plate, a second end of the elastic member is connected to a second sleeve, the second sleeve is connected to the second buffer plate, and the second sleeve squeezes the elastic member when moving upward along the sliding shaft.

5. The nut tightening device according to claim 4, characterized in that: A mounting block is further provided between the second sleeve and the second buffer plate, and the mounting block is connected to the driving assembly, and the driving assembly is used to drive the mounting block to move upwards, so as to push the second sleeve to move upwards.

6. The nut tightening device according to claim 1, characterized in that: The driving assembly includes a servo motor, an output shaft of the servo motor is connected to the tightening assembly, and the output shaft of the servo motor is used to drive the tightening assembly to rotate.

7. The nut tightening device according to claim 5, characterized in that: A side of the mounting block away from the second sleeve is connected to a shaft seat, and the tightening assembly is mounted on the shaft seat.

8. The nut tightening device according to claim 6, characterized in that: The tightening assembly also includes a connecting rod, a first end of the connecting rod is connected to the output shaft of the servo motor, and a second end of the connecting rod is connected to the suction cup.

9. A nut tightening method, characterized in that: Based on the nut tightening device according to any one of claims 1 to 8, the method comprises: Move the nut tightening device to the feeding position, and control the suction cup to absorb the nut into the first sleeve; Move the nut tightening device to the processing position, and align the tightening assembly with the stop valve stud; The tightening assembly moves downward, driving the nut to move downward; The driving assembly drives the nut to rotate so as to tighten the nut onto the stop valve stud.

10. The nut tightening method according to claim 9, characterized in that: The tightening assembly moves downward, driving the nut to move downward, including: Lift the mounting block upward; The second sleeve squeezes the elastic member so that the elastic member is compressed; The elastic member gradually recovers its deformation, driving the nut to move downward.

11. The nut tightening method according to claim 10, characterized in that: The driving assembly drives the nut to rotate so as to tighten the nut on the stop valve stud, comprising: Get the current torque of the servo motor; If the current torque is less than the starting torque, maintaining the starting torque; If the current torque is greater than or equal to the starting torque and less than the target torque, the torque is increased linearly; If the current torque is greater than or equal to the target torque, the servo motor is controlled to stop running.

Images