Displacement detection device for installing screw rod of automobile part

Abstract

The invention relates to the technical field of screw installation displacement monitoring, and particularly discloses a displacement detection device for screw installation of automobile parts, which comprises a holding cylinder and a lower electrode cover, a positioning hole is formed in the lower electrode cover, a positioning pin is arranged in the holding cylinder in a lifting manner, and a displacement assembly for controlling and detecting the displacement of the positioning pin is arranged on the holding cylinder; an adjusting ring is rotationally connected into the holding cylinder, a driven ring is arranged at the bottom of the adjusting ring, a plurality of clamping plates are arranged on the adjusting ring and the driven ring in a sliding mode, sliding grooves are formed in the adjusting ring and the driven ring, sliding rods are fixedly connected to the clamping plates, and elastic ropes in a contraction state are arranged between the adjacent sliding rods. One end, close to the lower electrode cover, of the clamping plate on the adjusting ring is fixedly connected with an expansion plate; a vertical follow-up assembly used for controlling the driven ring to move is arranged in the holding cylinder, and a driving assembly used for driving the driven ring to rotate is arranged on the adjusting ring. The screw welding device has the effect of preventing the screw from toppling over and welding mistakes.

Description

Technical Field

[0001] The present application relates to the technical field of screw rod installation displacement monitoring, and in particular to a displacement detection device for screw rod installation of automobile parts. Background Art

[0002] The assembly and welding of screw rods are widely used in automobile manufacturing. In the process of welding screw rods to plates, projection welding machines are commonly used machines in this welding process. Projection welding machines are welding equipment that uses pneumatic pressurization, bearing guides, and microcomputer control boxes for automatic control. They have the characteristics of precise welding point control and good electrode follow-up performance.

[0003] During welding, first place the plate on the lower electrode cover so that the hole of the plate is opposite to the positioning hole, then insert the screw through the positioning hole into the grip tube, and then press the upper electrode cover down to compress the workpiece between the upper and lower motor plates. At the same time, the bumps on the workpiece are quickly melted by the heat, and then quickly cooled and solidified, so that the bumps and the workpiece are tightly combined.

[0004] With respect to the above-mentioned related technologies, the inventors believe that the following defects exist: in the actual welding process, screws are sometimes mixed, which leads to the screws being incorrectly welded to the plate; at the same time, in order to facilitate the insertion of the screw into the grip, the aperture of the positioning hole is generally larger than the aperture of the screw, and the screw is prone to displacement at this time. Moreover, since the plate is generally irregular in shape and its center of gravity is not located on the lower electrode cover, the plate placed on the lower electrode cover is prone to tipping over, causing the screw to be tilted and lifted, thereby affecting the subsequent welding quality. Summary of the invention

[0005] In order to improve the problem that screws are prone to tipping over and welding errors, the present application provides a displacement detection device for installing screws of automotive parts.

[0006] The present application provides a displacement detection device for screw installation of automotive parts, which adopts the following technical solution: A displacement detection device for screw installation of automotive parts, comprising a grip tube and a lower electrode cover fixedly connected to the top of the grip tube, wherein a positioning hole is provided on the lower electrode cover, and the device is characterized in that: a positioning pin aligned with the positioning hole is provided in the grip tube, and a displacement assembly for controlling and detecting the displacement of the positioning pin is provided on the grip tube; An adjusting ring is rotatably connected in the grip tube, a driven ring is arranged at the bottom of the adjusting ring, a plurality of clamping plates are slidably arranged on the adjusting ring and the driven ring, sliding grooves corresponding to the clamping plates are opened on the adjusting ring and the driven ring, a sliding rod slidably connected to the adjusting groove is fixedly connected to the clamping plate, when the sliding rod moves along the sliding groove, the clamping plates at the same height expand or contract, the adjusting ring or the driven ring rotates, a plurality of elastic ropes are arranged between adjacent sliding rods, and the elastic ropes are always in a contracted state, an expansion plate is fixedly connected to one end of the clamping plate on the adjusting ring close to the lower electrode cover, and the end of the expansion plate close to the lower electrode cover is inclined toward the end away from the positioning pin; A vertical follower assembly for controlling the driven ring to move along the vertical direction with the positioning pin and preventing the clamping plate on the driven ring from expanding is arranged in the grip tube, and a driving assembly for driving the driven ring to rotate is arranged on the adjustment ring.

[0007] By adopting the above technical solution, the plate is placed on the lower electrode cover, and the hole of the plate is aligned with the positioning hole. Then, before the screw is inserted into the positioning hole and the positioning pin is squeezed, the screw squeezes the expansion plate. Due to the action of the slide rod slide groove, the adjustment ring rotates, and the expansion plate and the clamping plate move away from the positioning pin. The rotation of the adjustment ring drives the driven ring to rotate through the driving component, and then the clamping plate on the driven ring is also expanded. When the screw squeezes the positioning pin and continues to move downward, the driven ring is driven to move downward through the vertical follower component and the clamping plate on the driven ring is prevented from being held. Expand, so that the clamping plate on the driven ring always clamps the bottom end of the screw, effectively avoiding the screw from tipping over, and because the movement degree of the sliding bars at the same height is always equal, combined with the clamping effect of the elastic rope, the screw is located at the center of the positioning hole when it is not disturbed by external force; when the screw is pressed to the specified position, the displacement component receives the displacement data of the positioning pin and compares it with the standard screw. If the displacement of the positioning pin is within the specified range, the screw is correct. If the displacement of the positioning pin exceeds the range, an alarm is issued to avoid the phenomenon of wrong screw welding.

[0008] Optionally, the displacement assembly includes a double-headed cylinder fixedly connected to the bottom of the grip tube, a connecting shaft fixedly connected to the bottom of the locating pin, a protective cover fixedly connected to the double-headed cylinder, and a displacement sensor fixedly connected within the protective cover, wherein one end of the connecting shaft away from the grip tube is fixedly connected to the upper piston rod end of the double-headed cylinder, and the input end of the displacement sensor is fixedly connected to the lower piston rod end of the double-headed cylinder.

[0009] By adopting the above technical solution, when the locating pin moves downward, the connecting shaft is pushed downward by the locating pin, thereby causing the upper piston rod end and the lower piston rod end of the double-headed cylinder to move downward, and the lower piston rod end of the double-headed cylinder pushes the input end of the displacement sensor downward to detect the displacement of the locating pin. When the screw is welded, the plate and the screw can be removed manually or by a robot, or the locating pin can be driven by the double-headed cylinder to push out the screw, so as to assist the staff in removing the welded workpiece and prevent the screw from being fixed too tightly by the clamping plate and difficult to pull out. After the welded screw is removed, the double-headed cylinder is reset again to carry out the next cycle of operation.

[0010] Optionally, the vertical follower assembly includes a plurality of elastic telescopic rods fixedly connected to the bottom end of the adjusting ring, a ball roller arranged at the free end of the elastic telescopic rod and an elastic block arranged at the bottom end of the driven ring, the positioning pin is provided with a slot matching the elastic block, the upper end surface of the elastic block fitting the slot wall is horizontal, and the lower end is inclined, the positioning pin passes through the driven ring, the clamping plate on the driven ring is not lower than the height of the top of the positioning pin, and the driven ring is provided with an annular rolling groove matching the ball roller.

[0011] By adopting the above technical solution, when the screw shakes, the bottom of the screw shakes the most. When the screw squeezes the positioning pin and moves downward, the elastic clamping block is clamped in the clamping slot, causing the elastic telescopic rod to extend and the driven ring to move downward, so that the clamping plate on the driven ring always clamps the bottom of the screw, thereby effectively clamping the screw. The elastic telescopic rod increases the pressure between the elastic clamping block and the groove wall of the clamping slot, thereby increasing the friction force on the elastic clamping block, and cooperating with the elastic force of the elastic rope to effectively prevent the clamping plate from being pushed by the screw and expanding, thereby tightening the locking screw.

[0012] Optionally, the parts where the elastic card block and the slot wall of the card slot are in contact with each other are both provided with a friction layer.

[0013] By adopting the above technical solution, after the positioning pin moves downward, the friction layer between the elastic clamping block and the groove wall of the clamping groove further increases the friction force exerted on the elastic clamping block, thereby making the clamping plate clamp the screw rod tighter.

[0014] Optionally, the elastic telescopic rod is a constant force spring telescopic rod, and the elastic force of the elastic telescopic rod is slightly greater than the sum of the gravity of the driven ring, the clamping plate and the sliding rod.

[0015] By adopting the above technical solution, the constant force of the elastic telescopic rod ensures that when the locating pin presses down screws of various lengths, the pulling force of the elastic block on the locating pin is equal, thereby avoiding excessive pulling force on the locating pin when pressing down a screw that is too long, making it difficult for the screw to descend to the specified position.

[0016] Optionally, the driving assembly includes a driving rod fixedly connected to the bottom of the adjusting ring and a tooth block fixedly connected to the bottom end of the driving rod, the driven ring is provided with a tooth groove that matches the tooth block, and when the positioning pin is not squeezed by the bolt, the tooth block engages with the tooth groove.

[0017] By adopting the above technical scheme, when the screw squeezes the expansion plate, the clamping plate on the adjusting ring expands and the adjusting ring rotates, and since the tooth block is engaged with the tooth groove, the driven ring is driven by the driving rod to rotate; when the positioning pin is moved downward by the downward pressure of the screw, the tooth block is disengaged from the tooth groove, and the driven ring is rotated without being affected by the rotation of the adjusting ring. For example, when the screw is a conical screw, the clamping plate on the adjusting ring continues to expand and the adjusting ring continues to rotate, and the clamping plate on the driven ring is tightly clamped by the elastic force of the elastic rope to the top of the screw.

[0018] Optionally, a first electromagnet is fixedly connected to one end of the grip tube close to the lower electrode cover, and a second electromagnet is fixedly connected to the positioning pin. The second electromagnet is always located below the plate, and when the first electromagnet is in operation, the ends of the plate and the second electromagnet close to each other have the same magnetic properties.

[0019] By adopting the above technical scheme, when it is necessary to weld the nut and the plate, the positioning pin is raised by the displacement assembly so that the positioning pin rises above the lower electrode cover. At this time, the plate and the nut are put on the positioning pin. When the caliber of the nut is larger than the diameter of the positioning pin, and when the plate and the nut are small in size and light in weight, the first electromagnet is operated. At this time, the plate is affected by the magnetic field of the first electromagnet, so that the upper end of the plate is the same as the upper end of the first electromagnet. Since the plate and the nut are in close contact, the nut is affected by the magnetic field of the plate so that the upper end of the nut is the same as the upper end of the plate. That is, the bottom ends of the plate and the nut are isotropic with the top end of the second electromagnet. At this time, the nut and the plate are both subject to the repulsive force of the second electromagnet and tend to move away from the positioning pin. However, if the nut is offset, the repulsive force on the nut will be unbalanced, so that the nut always tends to the center of the positioning pin, and when the opening of the plate is located at the center of gravity of the plate, the plate is not easy to offset.

[0020] Optionally, the upper half of the positioning pin is tapered.

[0021] By adopting the above technical solution, when the displacement assembly raises the positioning pin to above the lower electrode cover, the conical positioning pin is more convenient for placing the nut and the plate at the correct position when the plate and nut have a smaller diameter than the positioning pin.

[0022] Optionally, a water-cooling heat dissipation tube is sleeved on one end of the grip tube close to the lower electrode cover.

[0023] By adopting the above technical solution, during welding operation, the water-cooled heat sink provides better heat dissipation for the grip tube, thereby preventing the grip tube and other internal structures from being overheated during long-term welding.

[0024] In summary, the present application includes at least one of the following beneficial technical effects: 1. When the screw is installed at the specified position, the displacement sensor receives the displacement data of the positioning pin and compares it with the standard screw. If the displacement of the positioning pin is within the specified range, the screw is correct. If the displacement of the positioning pin exceeds the range, an alarm is issued to avoid the phenomenon of wrong screw welding; 2. After the screw enters the gripping tube, the screw squeezes the expansion plate, causing the adjustment ring to rotate, and the expansion plate and the clamping plate to move away from the positioning pin. The rotation of the adjustment ring causes the driven ring to rotate through the driving assembly, thereby expanding the clamping plate on the driven ring. When the screw squeezes the positioning pin and continues to move downward, the vertical follower assembly drives the driven ring to move downward and prevents the clamping plate on the driven ring from expanding, thereby making the clamping plate on the driven ring always clamp the bottom end of the screw, effectively avoiding the phenomenon of the screw tipping over. Moreover, since the movement degree of the sliding rods at the same height is always equal, combined with the clamping effect of the elastic rope, the screw is located at the center of the positioning hole when it is not disturbed by external forces. 3. After the screw is welded, the plate and screw can be removed manually or by a robot, or the double-headed cylinder can drive the positioning pin to push out the screw to assist the staff in taking out the welded workpiece and prevent the screw from being too tightly fixed by the clamping plate and difficult to pull out. After the welded screw is removed, the double-headed cylinder is reset again for the next cycle of operation. The double-headed cylinder has a large range of adjustment for the position of the positioning pin and high accuracy. 4. When the screw is shaken, the bottom of the screw shakes the most. When the screw squeezes the positioning pin and moves downward, the clamping plate on the driven ring always clamps the bottom of the screw, thereby effectively clamping the screw. The elastic telescopic rod increases the pressure between the elastic block and the groove wall of the groove, thereby increasing the friction force on the elastic block. With the elastic force of the elastic rope, the clamping plate is effectively prevented from being pushed and expanded by the screw, thereby locking the screw more tightly. At the same time, when the tooth block is disengaged from the tooth groove, the driven ring is not rotated by the adjustment ring. When welding a conical screw or a large-size screw, the clamping plate on the adjustment ring continues to expand and the adjustment ring continues to rotate. The clamping plate on the driven ring is tightly clamped by the elastic force of the elastic rope. 5. When it is necessary to weld the nut and the plate, when the diameter of the nut is larger than the diameter of the locating pin and the weight of the plate and the nut is lighter, the first electromagnet operates to make the bottom ends of the plate and the nut and the top end of the second electromagnet is isotropic. At this time, the nut and the plate are both subject to the repulsive force of the second electromagnet, that is, the closer the inner wall of the hole of the nut and the plate is to the side of the locating pin, the greater the repulsive force is, so that the nut and the plate always tend to the center of the locating pin. When the diameter of the plate and the nut is smaller than the maximum diameter of the locating pin, the tapered part of the locating pin also makes it easier to place the nut and the plate in the correct position. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application; Figure 2 is along Figure 1 Schematic diagram of the cross-sectional structure along the AA line; Figure 3 This is a schematic diagram mainly used in this application to show the adjusting ring, the expansion plate, the driven ring, the clamping plate, the slide groove, the slide rod, the elastic rope, the vertical follower assembly and the driving assembly; Figure 4 This is a partial cross-sectional structural schematic diagram used in the present application to show the nut, the plate, the positioning pin, the first electromagnet and the second electromagnet; Figure 5 It is a schematic diagram of the structure after the present application is assembled to the body of a projection welding machine.

[0026] Figure numerals: 1. grip tube; 11. lower electrode cover; 111. positioning hole; 12. positioning pin; 2. displacement assembly; 21. double-headed cylinder; 22. connecting shaft; 23. protective cover; 24. displacement sensor; 31. adjusting ring; 311. expansion plate; 32. driven ring; 33. clamping plate; 34. slide groove; 35. slide rod; 36. elastic rope; 4. vertical follower assembly; 41. elastic telescopic rod; 42. ball bearing; 43. elastic block; 44. slot; 45. rolling groove; 5. driving assembly; 51. driving rod; 52. tooth block; 53. tooth groove; 61. first electromagnet; 62. second electromagnet; 7. water-cooled heat sink; 81. screw; 82. plate; 83. nut. DETAILED DESCRIPTION

[0027] The following is combined with Figure 1-5 This application is described in further detail.

[0028] The present application discloses a displacement detection device for screw installation of automotive parts. Figure 1 , Figure 2 and Figure 3The displacement detection device for screw installation of automobile parts includes a grip tube 1 and a lower electrode cover 11 fixed to the top of the grip tube 1, a positioning hole 111 is opened on the lower electrode cover 11, a positioning pin 12 aligned with the positioning hole 111 is provided in the grip tube 1, and a displacement component 2 for controlling and detecting the displacement of the positioning pin 12 is provided on the grip tube 1.

[0029] An adjusting ring 31 is rotatably connected inside the grip tube 1, and a driven ring 32 is arranged at the bottom of the adjusting ring 31. A plurality of clamping plates 33 are slidably arranged on the adjusting ring 31 and the driven ring 32. Slide grooves 34 corresponding to the clamping plates 33 are opened on the adjusting ring 31 and the driven ring 32. A sliding rod 35 slidably connected to the adjusting groove is fixed on the clamping plate 33. When the sliding rod 35 moves along the sliding groove 34, the clamping plates 33 at the same height expand or contract, and the adjusting ring 31 or the driven ring 32 rotates. A plurality of elastic ropes 36 are arranged between adjacent sliding rods 35, and the elastic ropes 36 are always in a contracted state. In other feasible embodiments, the elastic rope 36 can be replaced by a clockwork spring with one end fixed to the outer peripheral wall of the adjusting ring 31, that is, the clockwork spring drives the adjusting ring 31 to always push the clamping plate 33 to contract. An expansion plate 311 is fixedly connected to one end of the clamping plate 33 on the adjustment ring 31 close to the lower electrode cover 11 , and the end of the expansion plate 311 close to the lower electrode cover 11 is inclined toward the end away from the positioning pin 12 .

[0030] A vertical follower assembly 4 is provided in the grip tube 1 for controlling the driven ring 32 to move along the vertical direction with the positioning pin 12 and preventing the clamping plate 33 on the driven ring 32 from expanding. A driving assembly 5 is provided on the adjusting ring 31 for driving the driven ring 32 to rotate.

[0031] The plate 82 is placed on the lower electrode cover 11, and the hole of the plate 82 is aligned with the positioning hole 111. Then, the screw 81 is inserted into the positioning hole 111 and before the positioning pin 12 is squeezed, the screw 81 squeezes the expansion plate 311. Due to the action of the slide groove 34 of the slide bar 35, the adjustment ring 31 is rotated, and the expansion plate 311 and the clamping plate 33 move away from the positioning pin 12. The rotation of the adjustment ring 31 causes the driven ring 32 to rotate accordingly through the driving component 5, thereby causing the clamping plate 33 on the driven ring 32 to expand accordingly. When the screw 81 squeezes the positioning pin 12 and continues to move downward, the driven ring 32 is driven downward by the vertical follower component 4 and the driven ring 32 is prevented from moving upward. The clamping plate 33 expands, so that the clamping plate 33 on the driven ring 32 always clamps the bottom end of the screw 81, effectively avoiding the screw 81 from tipping over. Since the movement degree of the sliding rod 35 at the same height is always equal, combined with the clamping effect of the elastic rope 36, the screw 81 is located at the center of the positioning hole 111 when it is not disturbed by external force. When the screw 81 is pressed to the specified position, the displacement component 2 receives the displacement data of the positioning pin 12 and compares it with the standard screw 81. If the displacement of the positioning pin 12 is within the specified range, the screw 81 is correct. If the displacement of the positioning pin 12 exceeds the range, an alarm is issued to avoid the phenomenon of incorrect welding of the screw 81.

[0032] Reference Figure 2 The displacement assembly 2 includes a double-headed cylinder 21 fixedly connected to the bottom of the grip tube 1, a connecting shaft 22 fixedly connected to the bottom of the positioning pin 12, a protective cover 23 fixedly connected to the double-headed cylinder 21 and a displacement sensor 24 fixedly connected in the protective cover 23. The end of the connecting shaft 22 away from the grip tube 1 is fixedly connected to the upper piston rod end of the double-headed cylinder 21, and the input end of the displacement sensor 24 is fixedly connected to the lower piston rod end of the double-headed cylinder 21.

[0033] When the locating pin 12 moves downward, the connecting shaft 22 is pushed downward by the locating pin 12, thereby causing the upper piston rod end and the lower piston rod end of the double-headed cylinder 21 to move downward, and the lower piston rod end of the double-headed cylinder 21 pushes the input end of the displacement sensor 24 downward to detect the displacement of the locating pin 12. When the welding of the screw 81 is completed, the plate 82 and the screw 81 can be removed manually or by a robot, or the locating pin 12 can be driven by the double-headed cylinder 21 to push out the screw 81, so as to assist the staff in removing the welded workpiece and prevent the screw 81 from being fixed too tightly by the clamping plate 33 and difficult to pull out. After the welded screw 81 is removed, the double-headed cylinder 21 is reset again to perform the next cycle of operation.

[0034] Reference Figure 3The vertical follower assembly 4 includes a plurality of elastic telescopic rods 41 fixedly connected to the bottom end of the adjusting ring 31, a ball 42 arranged at the free end of the elastic telescopic rod 41 and an elastic block 43 arranged at the bottom end of the driven ring 32. A card slot 44 adapted to the elastic block 43 is provided on the positioning pin 12. The elastic telescopic rod 41 is a constant force spring telescopic rod, and the elastic force of the elastic telescopic rod 41 is slightly greater than the sum of the gravity of the driven ring 32, the clamping plate 33 and the sliding rod 35. The upper end surface of the elastic block 43 that fits the groove wall of the card slot 44 is horizontal and the lower end is inclined. The positioning pin 12 passes through the driven ring 32. The clamping plate 33 on the driven ring 32 is not lower than the height of the top of the positioning pin 12. The driven ring 32 is provided with an annular rolling groove 45 adapted to the ball 42.

[0035] In the present application, a stabilizing plate is also slidably connected to the bottom of the clamping plate 33 on the driven ring 32 in the grip tube 1, and the elastic block 43 is fixed to the bottom of the stabilizing plate through an elastic rod. The stabilizing plate effectively improves the stability of the clamping plate 33 during the clamping process and during movement. The parts where the elastic block 43 and the groove walls of the groove 44 fit each other are provided with a friction layer to increase the friction coefficient between the elastic block 43 and the groove 44, further preventing the screw 81 from pushing the clamping plate 33 on the driven ring 32. The friction layer can be a friction groove opened on the groove wall surface of the elastic block 43 and the groove 44.

[0036] When the screw 81 shakes, the bottom of the screw 81 shakes the most. When the screw 81 squeezes the positioning pin 12 and moves downward, the elastic block 43 is clamped in the slot 44, so that the elastic telescopic rod 41 is extended and the driven ring 32 moves downward, so that the clamping plate 33 on the driven ring 32 always clamps the bottom of the screw 81, thereby effectively clamping the screw 81, and the elastic telescopic rod 41 increases the pressure between the elastic block 43 and the groove wall of the slot 44, thereby increasing the friction force on the elastic block 43, and cooperating with the elastic force of the elastic rope 36, effectively preventing the clamping plate 33 from being pushed and expanded by the screw 81, thereby tightening the locking screw 81; the constant force of the elastic telescopic rod 41 makes the positioning pin 12 receive the same pulling force from the elastic block 43 when pressing down screws 81 of various lengths, so as to avoid excessive pulling force on the positioning pin 12 when the over-long screw 81 is pressed down, which makes it difficult for the screw 81 to descend to the specified position.

[0037] Reference Figure 2 and Figure 3The driving assembly 5 includes a driving rod 51 fixed to the bottom of the adjusting ring 31 and a tooth block 52 fixed to the bottom end of the driving rod 51. The driven ring 32 is provided with a tooth groove 53 that meshes with the tooth block 52, and when the positioning pin 12 is not squeezed by the screw 81, the tooth block 52 meshes with the tooth groove 53. When the screw 81 squeezes the expansion plate 311, the clamping plate 33 on the adjusting ring 31 expands and the adjusting ring 31 rotates. Since the tooth block 52 is meshed with the tooth groove 53, the driven ring 32 is driven by the driving rod 51 to rotate; when the positioning pin 12 is pressed down by the screw 81 and moves downward, the tooth block 52 is disengaged from the tooth groove 53. At this time, the driven ring 32 is not rotated by the adjusting ring 31 but rotates. For example, when the screw 81 is a conical screw 81, the clamping plate 33 on the adjusting ring 31 continues to expand and the adjusting ring 31 continues to rotate. The clamping plate 33 on the driven ring 32 is tightly clamped by the elastic force of the elastic rope 36 to the top of the screw 81.

[0038] Reference Figure 4 and Figure 5 A first electromagnet 61 is fixedly connected to one end of the grip tube 1 near the lower electrode cover 11, and a second electromagnet 62 is fixedly connected to the positioning pin 12. The second electromagnet 62 is always located below the plate 82, and when the first electromagnet 61 is running, the magnetic properties of the plate 82 and the second electromagnet 62 at one end near each other are the same, and the upper half of the positioning pin 12 is conical.

[0039] When it is necessary to weld the nut 83 and the plate 82, the positioning pin 12 is raised by the displacement assembly 2 so that the positioning pin 12 rises above the lower electrode cover 11, and then the plate 82 and the nut 83 are sleeved on the positioning pin 12. When the diameter of the nut 83 is larger than the diameter of the positioning pin 12, the plate 82 and the nut 83 are ferromagnetic and have a small size and a light weight, the first electromagnet 61 is in operation, and at this time the plate 82 is affected by the magnetic field of the first electromagnet 61 and produces an induced magnetization phenomenon, that is, the magnetic field of the first electromagnet 61 rearranges the magnetic domains inside the plate 82, and at this time the plate 82 becomes a temporary magnet, so that the upper end of the plate 82 has the same magnetic pole as the upper end of the first electromagnet 61, and because the plate 82 is in close contact with the nut 83, the nut 83 is affected by the magnetic field of the plate 82, so that the upper end of the nut 83 is aligned with the plate 8 2 The upper magnetic poles are the same, that is, the bottom ends of the plate 82 and the nut 83 are the same as the top end of the second electromagnet 62. At this time, the nut 83 and the plate 82 are both subject to the repulsive force of the second electromagnet 62 and tend to move away from the positioning pin 12. However, if the nut 83 is offset, the repulsive force on the nut 83 will be unbalanced, that is, the closer the inner wall of the hole of the nut 83 and the plate 82 is to the side of the positioning pin 12, the greater the repulsive force, so that the nut 83 always tends to the center of the positioning pin 12, and when the opening of the plate 82 is located at the center of gravity of the plate 82, the plate 82 is not easy to deviate. When the diameter of the plate 82 and the nut 83 is smaller than the maximum diameter of the positioning pin 12, the tapered part of the positioning pin 12 is also more convenient for the nut 83 and the plate 82 to be placed in the correct position.

[0040] Reference Figure 1 One end of the grip tube 1 close to the lower electrode cover 11 is provided with a water-cooled heat sink 7 connected to circulating water. During welding operation, the water-cooled heat sink 7 provides better heat dissipation for the grip tube 1 to avoid excessive temperature of the grip tube 1 and other internal structures during long-term welding.

[0041] The implementation principle of the displacement detection device for installing the screw 81 of an automobile component in the embodiment of the present application is as follows: when welding the screw 81, bolt, screw and other rod-shaped objects with the plate 82, the plate 82 is placed on the lower electrode cover 11, and the hole of the plate 82 is aligned with the positioning hole 111, and then the screw 81 is inserted into the positioning hole 111, and the screw 81 squeezes the expansion plate 311. Due to the action of the slide groove 34 of the slide rod 35, the adjustment ring 31 is rotated, and the expansion plate 311 and the clamping plate 33 are moved away from the positioning pin 12. Since the tooth block 52 is meshed with the tooth groove 53, the driven ring 32 is driven by the driving rod 51 to rotate, and then the clamping plate 33 on the driven ring 32 is also expanded; When the screw 81 squeezes the positioning pin 12 and continues to move downward, the tooth block 52 is disengaged from the tooth groove 53. At this time, the driven ring 32 is not rotated by the adjusting ring 31 but rotates synchronously, effectively preventing the clamping plate 33 from being pushed and expanded by the screw 81, thereby locking the screw 81 more tightly until the screw 81 moves downward to the specified position. The displacement sensor 24 also receives the displacement distance of the screw 81, and determines whether the model of the screw 81 is wrong by comparing it with the qualified displacement range. After welding is completed, the screw rod 81 and the plate 82 can be removed by manually or mechanically grasping or by using the double-headed cylinder 21 to move the screw rod 81 upward so that the screw rod 81 breaks through the restriction of the clamping plate 33. The operation is simple.

[0042] When welding the nut 83 and the plate 82, the positioning pin 12 is raised to the top of the lower electrode cover 11, and then the plate 82 and the nut 83 are sleeved on the positioning pin 12. When the maximum diameter of the positioning pin 12 is larger than the diameter of the plate 82 and the nut 83, the tapered part of the positioning pin 12 facilitates the placement of the nut 83 and the plate 82 at the correct position. The upper electrode cover is pressed down to press the positioning pin 12 down to the same height as the nut 83, and then welding is performed. After welding, the plate 82 can be directly taken out. When the diameter of the nut 83 and the plate 82 is larger than the diameter of the positioning pin 12, the first electromagnet 61 is in operation. At this time, the plate 82 is affected by the magnetic field of the first electromagnet 61, so that the upper end of the plate 82 is the same as the upper end of the first electromagnet 61. Because the plate 82 and the nut 83 are in close contact, the nut 83 is affected by the magnetic field of the plate 82, so that the upper end of the nut 83 is the same as the upper end of the plate 82. That is, the bottom ends of the plate 82 and the nut 83 are isotropic with the top of the second electromagnet 62. At this time, the nut 83 and the plate 82 are both subject to the repulsive force of the second electromagnet 62 and tend to move away from the positioning pin 12. However, if the nut 83 is offset, the repulsive force on the nut 83 will be unbalanced, so that the nut 83 always tends to the center of the positioning pin 12, and when the opening of the plate 82 is located at the center of gravity of the plate 82, the plate 82 is not easy to offset.

[0043] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A displacement detection device for screw installation of automotive parts, comprising a grip tube (1) and a lower electrode cover (11) fixedly connected to the top of the grip tube (1), wherein a positioning hole (111) is provided on the lower electrode cover (11), characterized in that: A positioning pin (12) aligned with the positioning hole (111) is provided in the grip tube (1) for lifting and lowering, and a displacement component (2) for controlling and detecting the displacement of the positioning pin (12) is provided on the grip tube (1); An adjusting ring (31) is rotatably connected inside the grip tube (1), a driven ring (32) is arranged at the bottom of the adjusting ring (31), a plurality of clamping plates (33) are slidably arranged on the adjusting ring (31) and the driven ring (32), a sliding groove (34) corresponding to the clamping plates (33) is opened on the adjusting ring (31) and the driven ring (32), a sliding rod (35) slidably connected to the adjusting groove is fixed on the clamping plate (33), and when the sliding rod (35) moves along the sliding groove (34), all the clamping plates (33) at the same height are The clamping plate (33) expands or contracts, the adjusting ring (31) or the driven ring (32) rotates, a plurality of elastic ropes (36) are arranged between adjacent sliding rods (35), and the elastic ropes (36) are always in a contracted state, and an expansion plate (311) is fixedly connected to one end of the clamping plate (33) on the adjusting ring (31) close to the lower electrode cover (11), and one end of the expansion plate (311) close to the lower electrode cover (11) is inclined toward an end away from the positioning pin (12); The grip tube (1) is provided with a vertical follower assembly (4) for controlling the driven ring (32) to move along the vertical direction with the positioning pin (12) and preventing the clamping plate (33) on the driven ring (32) from expanding, and the adjustment ring (31) is provided with a driving assembly (5) for driving the driven ring (32) to rotate.

2. A displacement detection device for screw installation of automotive parts according to claim 1, characterized in that: The displacement assembly (2) comprises a double-headed cylinder (21) fixedly connected to the bottom of the grip tube (1), a connecting shaft (22) fixedly connected to the bottom of the positioning pin (12), a protective cover (23) fixedly connected to the double-headed cylinder (21), and a displacement sensor (24) fixedly connected inside the protective cover (23), wherein one end of the connecting shaft (22) away from the grip tube (1) is fixedly connected to the upper piston rod end of the double-headed cylinder (21), and the input end of the displacement sensor (24) is fixedly connected to the lower piston rod end of the double-headed cylinder (21).

3. The displacement detection device for screw installation of automobile parts according to claim 1, characterized in that: The vertical follower assembly (4) comprises a plurality of elastic telescopic rods (41) fixedly connected to the bottom end of the adjusting ring (31), a ball (42) arranged at the free end of the elastic telescopic rod (41) and an elastic block (43) arranged at the bottom end of the driven ring (32); the positioning pin (12) is provided with a slot (44) adapted to the elastic block (43); the upper end surface of the elastic block (43) in contact with the slot wall of the slot (44) is horizontal, and the lower end is inclined; the positioning pin (12) passes through the driven ring (32); the clamping plate (33) on the driven ring (32) is not lower than the height of the top of the positioning pin (12); and the driven ring (32) is provided with an annular rolling groove (45) adapted to the ball (42).

4. A displacement detection device for screw installation of automotive parts according to claim 3, characterized in that: The portions of the elastic clamping block (43) and the groove wall of the clamping groove (44) that are in contact with each other are both provided with a friction layer.

5. The displacement detection device for screw installation of automobile parts according to claim 3, characterized in that: The elastic telescopic rod (41) is a constant-force spring telescopic rod, and the elastic force of the elastic telescopic rod (41) is slightly greater than the sum of the gravity of the driven ring (32), the clamping plate (33) and the sliding rod (35).

6. The displacement detection device for screw installation of automobile parts according to claim 1, characterized in that: The driving assembly (5) comprises a driving rod (51) fixedly connected to the bottom of the adjusting ring (31) and a tooth block (52) fixedly connected to the bottom end of the driving rod (51); the driven ring (32) is provided with a tooth groove (53) which meshes with the tooth block (52); and when the positioning pin (12) is not squeezed by the bolt, the tooth block (52) meshes with the tooth groove (53).

7. The displacement detection device for screw installation of automobile parts according to claim 1, characterized in that: A first electromagnet (61) is fixedly connected to one end of the grip tube (1) close to the lower electrode cover (11), and a second electromagnet (62) is fixedly connected to the positioning pin (12). The second electromagnet (62) is always located below the plate (82), and when the first electromagnet (61) is in operation, the plate (82) and the second electromagnet (62) have the same magnetic properties at one end close to each other.

8. The displacement detection device for screw installation of automobile parts according to claim 1, characterized in that: The upper part of the positioning pin (12) is tapered.

9. The displacement detection device for screw installation of automobile parts according to claim 1, characterized in that: One end of the grip tube (1) close to the lower electrode cover (11) is sleeved with a water-cooling heat dissipation tube (7).

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