Heavy truck chassis bolt tightening method, tightening device and tightening system

Abstract

The invention relates to a heavy truck chassis bolt tightening method, device and system. A heavy truck chassis bolt is assembled in an oil pressure pulse wrench pre-tightening mode and an electric tightening gun re-tightening mode. The re-tightening mode of the electric tightening guns comprises the steps that according to different tightening positions of heavy truck chassis bolts, the electric tightening guns of different structural forms are selected; when the airplane beam, the middle support, the tail beam and the frame ventral face are assembled, the electric tightening guns of different structural forms are provided with counter-force devices of different structural forms. The electric tightening guns of different structural forms are moved to different bolt tightening positions of the heavy truck chassis through the suspension device; suspension supports with different structural forms are respectively arranged on the electric tightening guns with different structural forms; the bolt tightening torque precision is controlled to be + / -1%-+ / -8%, the technological requirements are met by 100%, and the quality qualification rate is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile manufacturing, and particularly relates to a method for tightening bolts on a heavy truck chassis, a tightening device, and a tightening system. Background Art

[0002] Bolt connections play an indispensable role in the assembly processes of automobiles and machinery due to their simple structure and easy disassembly characteristics, and are often used in the installation of automobile chassis components and the connection of mechanical parts. During the bolt tightening process, the magnitude of the tightening torque directly affects the reliability of the bolt connection. If the torque is too small, the bolt is likely to loosen due to vibration, and if the torque is too large, it is easy to cause thread stripping or fracture. Currently, in the chassis assembly process of the heavy truck industry, different bolt specifications are used for different structural parts and sheet metal thicknesses. All bolts are tightened once with a pneumatic wrench, and the tightening torque depends on the experience of the operator and spot checks, which cannot ensure that the torque accuracy of all bolts meets the process requirements by 100%. In addition, the pneumatic wrench produces a large operating noise, and it is laborious for the operator to hold and operate, especially for bolts in narrow spaces where the operation difficulty is even greater. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for tightening bolts on a heavy truck chassis, a tightening device, and a tightening system in view of the deficiencies of the prior art.

[0004] The present invention is implemented by adopting the following technical solutions:

[0005] It includes:

[0006] For the assembly of bolts on the heavy truck chassis, an oil pressure pulse wrench pre-tightening method and an electric tightening gun re-tightening method are adopted;

[0007] The electric tightening gun re-tightening method includes:

[0008] According to the different tightening positions of bolts on the heavy truck chassis, electric tightening guns with different structural forms are selected; among them, when assembling the aircraft beam, the intermediate support, the tail beam, and the frame ventral surface, reaction devices with different structural forms are configured on the electric tightening guns with different structural forms;

[0009] The different structural forms of electric tightening guns are respectively moved to different bolt tightening positions on the heavy truck chassis by using a suspension device; among them, suspension supports with different structural forms are respectively configured on the electric tightening guns with different structural forms.

[0010] A tightening device for bolts on a heavy truck chassis includes the method for tightening bolts on a heavy truck chassis as described above. When assembling the aircraft beam, a pistol-type downward electric tightening gun is selected, and a first reaction device and a first suspension support are configured on the pistol-type downward electric tightening gun;

[0011] The reaction force device 1 includes a Z-direction reaction force rod support and a Z-direction reaction force rod. One end of the Z-direction reaction force rod is slidably connected to the sliding hole on the Z-direction reaction force rod support;

[0012] One side of the suspension support 1 is connected with a handle through a spherical joint, and a suspension mounting point 1 is arranged on the other side.

[0013] As a further description of the invention, when assembling the intermediate support, an L-shaped electric tightening gun is selected as the electric tightening gun. The L-shaped electric tightening gun is configured with a reaction force device 2, a suspension support 2, and an offset head;

[0014] The reaction force device 2 includes an L-shaped reaction force rod support, a rotating seat, a tension spring, and an L-shaped reaction force rod. One end of the L-shaped reaction force rod slidably penetrates through the rotating seat and is detachably inserted into different holes on the L-shaped reaction force rod support through the rotating seat. The tension spring is arranged between the rotating seat and the L-shaped reaction force rod;

[0015] The suspension support 2 is of an L-shaped structure. A suspension mounting point 1 is arranged on the top of the suspension support 2, and the L-shaped reaction force rod support, the rotating seat, and an offset head mounting seat are arranged on the bottom of the suspension support 2.

[0016] As a further description of the invention, when assembling the tail beam, an elbow-type electric tightening gun is selected as the electric tightening gun. The elbow-type electric tightening gun is configured with a reaction force device 3 and a suspension support 3;

[0017] The reaction force device 3 includes a reaction force rod support. A reaction force rod is arranged on the reaction force rod support. An elastic steel ball device is arranged on the reaction force rod. The reaction force rod is detachably inserted into the reaction force rod support through the elastic steel ball device;

[0018] A suspension mounting point 3 is arranged on the suspension support 3.

[0019] As a further description of the invention, when assembling the ventral surface of the vehicle frame, a pistol-type electric tightening gun is selected as the electric tightening gun. The pistol-type electric tightening gun is configured with a suspension support 4;

[0020] The suspension support 4 is of an L-shaped structure. A suspension mounting point 4 is arranged on the top of the suspension support 3.

[0021] As a further description of the invention, the suspension device includes a factory building overhead crane guide rail, a spring balancer, a pulley support, and a lifting rod. The top of the pulley support is slidably connected to the factory building overhead crane guide rail through a pulley. One end of the pulley support is provided with the spring balancer. The bottom of the pulley support is connected to the top of the lifting rod through a swing joint. An electric tightening gun mounting point is arranged at the bottom of the lifting rod. Tightening sleeves are arranged on the output ends of the electric tightening guns.

[0022] As a further illustration of the invention, the overhead crane guide rail in the workshop is an aluminum alloy guide rail.

[0023] As a further illustration of the invention, the lifting rod is a carbon fiber lifting rod.

[0024] The heavy truck chassis bolt tightening system includes the heavy truck chassis bolt tightening device as described in any one of the above, and further includes a controller, a barcode scanner, a printer, an operation instruction box, and a socket selector; the electric tightening gun, the barcode scanner, the printer, the operation instruction box, and the socket selector are all connected to the controller.

[0025] As a further illustration of the invention, it further includes a client and a remote control terminal; the controller is configured with an external storage interface and the Ethernet interface, and the client and the remote control terminal are both connected to the controller.

[0026] Compared with the prior art, the present invention has the following beneficial technical effects:

[0027] The present invention designs a set of bolt tightening process modes of "pre-tightening with an oil pressure pulse wrench + re-tightening with an electric tightening gun". Set the oil pressure pulse wrench to a preset torque value to quickly pre-tighten the bolts. Due to the structural limitations of the oil pressure pulse wrench, the torque accuracy range of the pre-tightened bolts is only within ±8% - ±20%. In the subsequent process, a low-noise and high-precision electric tightening gun is still required for re-tightening. The electric tightening gun eliminates the influence of the friction coefficient on the bolt torque attenuation by controlling the rotation angle, further accurately controlling the bolt torque, so that the bolt tightening torque accuracy is controlled within ±1% - ±8%, meeting the process requirements 100% and improving the quality qualification rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is the schematic diagram of the bolt assembly of the aircraft beam of the present invention;

[0029] Figure 2 is the schematic diagram of the structure of the L-shaped electric tightening gun of the present invention;

[0030] Figure 3 is Figure 2 the schematic diagram of the installation structure of the L-shaped reaction rod of

[0031] Figure 4 is the schematic diagram of the bolt assembly of the intermediate support of the present invention Figure 1 ;

[0032] Figure 5 is the schematic diagram of the bolt assembly of the intermediate support of the present invention Figure 2 ;

[0033] Figure 6 is the schematic diagram of the bolt assembly of the tail beam and the wing surface of the frame of the present invention;

[0034] Figure 7 is Figure 6 a sectional view of the reaction rod structure;

[0035] Figure 8 is a schematic diagram of the bolt assembly of the tail beam and the frame ventral surface of the present invention;

[0036] Figure 9 is a schematic diagram of the bolt assembly of the frame ventral surface of the present invention;

[0037] Figure 10 is a schematic diagram of the structure of the suspension device of the present invention.

[0038] In the figure: 10, a pistol-type electric tightening gun for downward use; 11, a first suspension support; 12, a first suspension mounting point; 13, a handle; 14, a Z-direction reaction rod support; 15, a sliding hole; 16, a Z-direction reaction rod; 17, a first sleeve;

[0039] 20, an L-type electric tightening gun; 21, a second suspension support; 22, a second suspension mounting point; 23, a second sleeve; 24, an L-type reaction rod support; 25, a rotating seat; 26, an L-type reaction rod; 27, an offset head; 28, a tension spring;

[0040] 30, an elbow-type electric tightening gun; 31, a reaction rod support; 32, a reaction rod; 33, a third suspension support; 34, a third suspension mounting point; 35, a third sleeve;

[0041] 40, a pistol-type electric tightening gun; 41, a fourth sleeve; 42, a fourth suspension support; 43, a fourth suspension mounting point;

[0042] 50, a suspension device; 52, a lifting rod; 52, a pulley bracket; 53, a spring balancer; 54, a swing joint; 55, an electric tightening gun mounting point. Specific embodiments

[0043] Embodiment 1

[0044] As Figure 1-10 shown, this embodiment provides a method for tightening bolts of a heavy truck chassis, including:

[0045] The bolt assembly of the heavy truck chassis adopts a pre-tightening method with an oil pressure pulse wrench and a re-tightening method with an electric tightening gun;

[0046] The re-tightening method with an electric tightening gun includes:

[0047] According to the different tightening positions of the bolts of the heavy truck chassis, electric tightening guns with different structural forms are selected; among them, when assembling the aircraft beam, the intermediate support, the tail beam and the frame ventral surface, reaction devices with different structural forms are configured on the electric tightening guns with different structural forms;

[0048] Use a suspension device to move electric tightening guns with different structural forms to different bolt tightening positions on the heavy truck chassis respectively; among them, suspension supports with different structural forms are respectively configured on the electric tightening guns with different structural forms.

[0049] Embodiment 2

[0050] As Figure 1-10 shown, this embodiment provides a bolt tightening device for a heavy truck chassis, adopting the above-mentioned bolt tightening method for the heavy truck chassis;

[0051] When assembling the aircraft beam, select the pistol-type downward electric tightening gun 10. The pistol-type downward electric tightening gun 10 is configured with a first reaction force device and a first suspension support 11;

[0052] The first reaction force device includes a Z-direction reaction force rod support 14 and a Z-direction reaction force rod 16. One end of the Z-direction reaction force rod 16 is slidably connected to the sliding hole 15 on the Z-direction reaction force rod support 14;

[0053] One side of the first suspension support 11 is connected with a handle 13 through a spherical joint, and a first suspension installation point 12 is arranged on the other side.

[0054] When assembling the aircraft beam as described above, the bolt assembly surface of the aircraft beam is horizontal with the ground. Use the pistol-type downward electric tightening gun 10, customize a Z-direction slidable non-standard sleeve reaction force rod. When tightening, the reaction force rod is sleeved on the adjacent bolts, and cooperate with the workpiece to be flipped to complete the assembly of the cross beam and the connecting plate. The maximum torque of the tool is 1000 N·m, the accuracy is ±3%, the weight is 7.3 Kg, the length is 486 cm, and the suspension device is adopted. The lifting guide can swing at a certain angle in the X-Y direction, the distance between the Z-direction reaction force rods 16 can be adjusted arbitrarily, the connection method between the handle 13 and the handle seat is a spherical joint connection, and the attitude of the handle 13 is adjustable.

[0055] When assembling the intermediate support as described above, select the L-type electric tightening gun 20. The L-type electric tightening gun 20 is configured with a second reaction force device, a second suspension support 21 and an offset head 27;

[0056] The second reaction force device includes an L-type reaction force rod support 24, a rotating seat 25, a tension spring 28, and an L-type reaction force rod 26; one end of the L-type reaction force rod 26 slidably penetrates through the rotating seat 25 and is detachably inserted into different holes on the L-type reaction force rod support 24 through the rotating seat 25, and a tension spring 28 is arranged between the rotating seat 25 and the L-type reaction force rod 26;

[0057] The second suspension support is of an L-type structure. A second suspension installation point 22 is arranged on the top of the second suspension support 21, and an L-type reaction force rod support 24, a rotating seat 25 and an offset head mounting seat are arranged on the bottom of the second suspension support 21.

[0058] For the above-mentioned assembly of the intermediate support, when using the L-shaped electric tightening gun 20 for bolt assembly in the narrow space inside the frame cavity, a non-standard L-shaped reaction bar is customized. The reaction bar has two assembly angles that can be quickly switched to adapt to the bolts on both the left and right sides. When tightening, the reaction bar leans against the workpiece to resist torsion. The maximum torque of the tool is 860 N·m, the accuracy is ±3%, the maximum weight is 9.5 Kg, and the length is 803 cm. A suspension device is used in combination, and the lifting guide can swing at a certain angle in the X-Y direction.

[0059] When assembling the tail beam, the elbow-type electric tightening gun 30 is selected. The elbow-type electric tightening gun 30 is equipped with a reaction device three and a suspension support three 33.

[0060] The reaction device three includes a reaction bar support 31. A reaction bar 32 is provided on the reaction bar support 31. An elastic steel ball device is provided on the reaction bar 32. The reaction bar 32 is detachably inserted into the reaction bar support 31 through the elastic steel ball device.

[0061] A suspension mounting point three 34 is provided on the suspension support three 33.

[0062] When assembling the above-mentioned tail beam, the elbow-type electric tightening gun is used. When assembling the connecting bolts between the tail beam and the longitudinal beam wing surface (vertical tightening), the electric tightening gun + customized sleeve reaction bar is used. The reaction bar forms torsion resistance on the longitudinal beam web surface. The inside of the reaction bar is an elastic steel ball clamping structure and can be quickly plugged and unplugged. When assembling the connecting bolts between the tail beam and the longitudinal beam web surface (horizontal tightening), the reaction bar is removed (as Figure 8 shown), and a carbon fiber rod is used to resist torsion. The maximum torque is 860 N·m, the equipment accuracy is ±3%, the weight is 10.3 Kg, and the length is 643 cm. The tool is suspended using an aluminum alloy track, and the spring balancer offsets the weight of the lifting components, and the carbon fiber tube provides telescopic guidance.

[0063] When assembling the frame web surface, the pistol-type electric tightening gun 40 is selected. The pistol-type electric tightening gun 40 is equipped with a suspension support four 42.

[0064] The suspension support four 42 is an L-shaped structure. A suspension mounting point four 43 is provided at the top of the suspension support four 42.

[0065] When assembling the above-mentioned intermediate support, cross beam, tail beam and frame web surface (the assembly surface is perpendicular to the ground), the pistol-type electric tightening gun 40 is used for bolt assembly. A suspension device is used in combination, and the lifting guide can swing at a certain angle in the X-Y direction, and no reaction bar is required. The maximum torque of the tool is 1000 N·m, the accuracy is ±3%, the maximum weight is 7.3 Kg, and the length is 486 cm.

[0066] The suspension device 50 includes a workshop overhead crane guide rail, a spring balancer 53, a pulley bracket 52, and a lifting rod 51; the top of the pulley bracket 52 is slidably connected to the workshop overhead crane guide rail through a pulley, one end of the pulley bracket 52 is provided with a spring balancer 53, the bottom of the pulley bracket 52 is connected to the top of the lifting rod 51 through a swing joint 54, and an electric tightening gun mounting point 55 is provided at the bottom of the lifting rod 51.

[0067] Tightening sleeves are provided on the output ends of the electric tightening guns. That is, a sleeve one 17 is provided on the output end of the pistol-type downward electric tightening gun, a sleeve two 23 is provided on the output end of the L-shaped electric tightening gun 20, a sleeve three 35 is provided on the output end of the elbow-type electric tightening gun 30, and a sleeve four 41 is provided on the output end of the pistol-type electric tightening gun 40.

[0068] The workshop overhead crane guide rail is an aluminum alloy guide rail.

[0069] The lifting rod is a carbon fiber lifting rod.

[0070] The above-mentioned suspension device uses an aluminum alloy guide rail, which is lighter in weight and has less inertia than a steel rail, and can be easily moved and stopped. The lifting guide uses a carbon fiber rod, which can swing in two planes parallel to and perpendicular to the guide rail, and can rotate / extend itself, with great flexibility. Compared with the connection with a soft rope, while ensuring rigidity, the carbon fiber rod also has a certain degree of flexibility. The maximum weight of the carbon fiber rod is only 2.8 Kg, and the maximum torsional resistance is 400 Nm. Compared with the conventional steel anti-torsion tube, under the condition of the same weight of the tightening mechanism, the carbon fiber rod can achieve the same function with a smaller balancer. The stroke can reach 1438 mm, the length when shortened is 962 mm, and after elongation, the length can reach 2400 mm. This feature ensures that the bolts at the lowest point can be covered during work; when not working, the tooling is higher than the worker's head to ensure safety. The traditional steel anti-torsion tube is a double-beam suspension, while a single beam of the carbon fiber tube is sufficient, making it more convenient to move. The operator can select different position sleeves on the sleeve selector, thereby determining the program for the tool to operate as determined by the controller. The overall equipment realizes lightweight and low resistance, taking into account both rigidity and flexibility, making the equipment move flexibly and recognize the nuts easily. At the same time, the carbon fiber rod itself has an anti-torsion function. When tightening horizontally, the reaction rod can be omitted, saving the alignment time, preventing damage to the workpiece, and avoiding confusion about the direction of reliance on the reaction rod.

[0071] Embodiment 3

[0072] As Figure 1-10 shown, this embodiment provides a heavy truck chassis bolt tightening system, which includes the above-mentioned heavy truck chassis bolt tightening device, and also includes a controller, a bar code scanner, a printer, an operation instruction box, and a sleeve selector; the electric tightening gun, the bar code scanner, the printer, the operation instruction box, and the sleeve selector are all connected to the controller;

[0073] It also includes a client and a remote control terminal; the controller is configured with an external storage interface and an Ethernet interface, and the controller communicates wirelessly with the client and the remote control terminal.

[0074] The above-mentioned controller is equipped with a good closed-loop control system, which can achieve torque control and precise angle control. After each tightening process is completed, whether the tightening value is qualified is indicated by corresponding indicator lights and data displays on the controller, and there are also indicator lights on the tightening tool; at the same time, the data can be traced from the start to the end of the tightening.

[0075] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. Method for tightening bolts of heavy truck chassis, characterized in that, Including: For the pre-tightening of heavy truck chassis bolts, an oil pressure pulse wrench pre-tightening method and an electric tightening gun re-tightening method are adopted. The electric tightening gun re-tightening method includes: According to the different tightening positions of heavy truck chassis bolts, electric tightening guns with different structural forms are selected; among them, when assembling the aircraft beam, intermediate support, tail beam, and the abdominal surface of the frame, reaction force devices with different structural forms are configured on the electric tightening guns with different structural forms. The suspension device is used to move the electric tightening guns with different structural forms to different bolt tightening positions on the heavy truck chassis respectively; among them, suspension supports with different structural forms are respectively configured on the electric tightening guns with different structural forms.

2. Heavy truck chassis bolt tightening device, including the heavy truck chassis bolt tightening method as described in claim 1, characterized in that, When assembling the aircraft beam, a pistol-type downward electric tightening gun is selected, and a reaction force device one and a suspension support one are configured on the pistol-type downward electric tightening gun. The reaction force device one includes a Z-direction reaction force rod support and a Z-direction reaction force rod, and one end of the Z-direction reaction force rod is slidably connected to the sliding hole on the Z-direction reaction force rod support. One side of the suspension support one is connected with a handle through a spherical joint, and a suspension installation point one is arranged on the other side.

3. The heavy truck chassis bolt tightening device according to claim 2, characterized in that, When assembling the intermediate support, an L-type electric tightening gun is selected, and a reaction force device two, a suspension support two, and an offset head are configured on the L-type electric tightening gun. The reaction force device two includes an L-type reaction force rod support, a rotating seat, a tension spring, and an L-type reaction force rod; one end of the L-type reaction force rod slidably penetrates through the rotating seat and is detachably inserted into different holes on the L-type reaction force rod support through the rotating seat, and the tension spring is arranged between the rotating seat and the L-type reaction force rod. The suspension support two is of an L-type structure, a suspension installation point one is arranged on the top of the suspension support two, and the L-type reaction force rod support, the rotating seat, and the offset head mounting seat are arranged on the bottom of the suspension support two.

4. The heavy truck chassis bolt tightening device according to claim 3, characterized in that, When assembling the tail beam, an elbow-type electric tightening gun is selected, and a reaction force device three and a suspension support three are configured on the elbow-type electric tightening gun. The reaction force device three includes a reaction force rod support, a reaction force rod is arranged on the reaction force rod support, an elastic steel ball device is arranged on the reaction force rod, and the reaction force rod is detachably inserted into the reaction force rod support through the elastic steel ball device. A suspension installation point three is arranged on the suspension support three.

5. The heavy truck chassis bolt tightening device according to claim 4, characterized in that, When assembling the abdominal surface of the frame, a pistol-type electric tightening gun is selected, and a suspension support four is configured on the pistol-type electric tightening gun. The suspension support four is of an L-type structure, and a suspension installation point four is arranged on the top of the suspension support three.

6. The heavy truck chassis bolt tightening device according to claim 5, characterized in that, The suspension device includes a factory building overhead crane rail, a spring balancer, a pulley support, and a lifting rod; the top of the pulley support is slidably connected to the factory building overhead crane rail through a pulley, one end of the pulley support is provided with the spring balancer, the bottom of the pulley support is connected to the top of the lifting rod through a swing joint, an electric tightening gun installation point is arranged at the bottom of the lifting rod, and a tightening sleeve is arranged on the output end of the electric tightening gun.

7. The heavy truck chassis bolt tightening device according to claim 6, characterized in that, The factory building overhead crane rail is an aluminum alloy rail.

8. The heavy truck chassis bolt tightening device according to claim 7, characterized in that, The lifting rod is a carbon fiber lifting rod.

9. Heavy truck chassis bolt tightening system, comprising the heavy truck chassis bolt tightening device according to any one of claims 2-8, characterized in that, It further includes a controller, a barcode scanner, a printer, an operation instruction box, and a socket selector; the electric tightening gun, the barcode scanner, the printer, the operation instruction box, and the socket selector are all connected to the controller.

10. The heavy truck chassis bolt tightening system according to claim 9, characterized in that, It further includes a client and a remote control terminal; the controller is configured with an external storage interface and the Ethernet interface, and both the client and the remote control terminal are connected to the controller.

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