Bolt tightening device

Abstract

The utility model discloses a bolt tightening device. The bolt tightening device comprises a rack; the counter-force counteracting mechanism comprises a gravity balancer, a first sliding rail, a second sliding rail and a third sliding rail, the first sliding rail is fixedly arranged on the rack, the second sliding rail is slidably installed on the first sliding rail, and the third sliding rail is slidably installed on the second sliding rail. The tightening mechanism comprises a mounting plate and a tightening shaft fixedly arranged on the mounting plate, the mounting plate is fixedly arranged on the third sliding rail, and the gravity balancer is connected with the mounting plate and used for absorbing acting force in the gravity direction; the collaborative robot is in signal connection with the tightening shaft and used for driving the tightening shaft to rotate; the operation end of the collaborative robot is connected with the mounting plate and used for driving the mounting plate to act relative to the rack; and the visual guiding mechanism is in signal connection with the collaborative robot and used for guiding the collaborative robot to act. The working mode that a pneumatic tightening tool is manually used for bolt tightening is avoided, and assembling consistency is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of automatic assembly, in particular to a bolt tightening device. Background Art

[0002] The function of the oil pan is to seal the crankcase as the outer shell of the oil tank to prevent impurities from entering, collect and store the lubricating oil flowing back from the friction surfaces of the diesel engine, dissipate some heat, and prevent the lubricating oil from oxidizing. The bolts of the oil pan of the diesel engine produced by the mixed line are mostly tightened manually, but the manual tightening of the oil pan bolts requires many repetitions, high labor intensity, poor assembly consistency, and the risk of oil leakage. Utility Model Content

[0003] The utility model discloses a bolt tightening device, which is used for improving color reproduction while ensuring imaging quality.

[0004] In order to achieve the above object, the utility model provides the following technical solutions:

[0005] A bolt tightening device, comprising:

[0006] frame;

[0007] The reaction force offset mechanism comprises a gravity balancer and a first slide rail, a second slide rail and a third slide rail, the extension directions of which are perpendicular to each other; the first slide rail is fixed to the frame, the second slide rail is slidably mounted on the first slide rail, and the third slide rail is slidably mounted on the second slide rail;

[0008] The tightening mechanism comprises a mounting plate and a tightening shaft fixed to the mounting plate, the mounting plate is fixed to the third slide rail, and the gravity balancer is connected to the mounting plate to absorb the force in the direction of gravity;

[0009] The collaborative robot is connected to the tightening shaft signal and is used to drive the tightening shaft to rotate; the operating end of the collaborative robot is connected to the mounting plate and is used to drive the mounting plate to move relative to the frame;

[0010] The visual guidance mechanism is connected to the collaborative robot signal and is used to guide the collaborative robot to move.

[0011] The bolt tightening device provided by the present application uses a visual guidance mechanism to guide the action of the collaborative robot, and the collaborative robot automatically drives the tightening shaft to tighten the bolts, avoiding the manual use of pneumatic tightening tools to tighten the bolts. This manual tightening method has labor intensity, low production efficiency, poor process stability, and quality problems such as incorrect and missed assembly of bolts, and the product quality is not controlled. Therefore, the present application uses a visual guidance robot to accurately tighten and ensure the consistency of assembly.

[0012] Moreover, since the load of the collaborative robot is small, the tightening shaft will generate reaction force during the tightening process, which is directly fed back to the collaborative robot, causing the robot to alarm. However, the present application sets a reaction force offset mechanism so that the collaborative robot only needs to walk the coordinates to complete the bolt tightening process. For ease of explanation, the extension direction of the first slide rail is defined as the X-axis, the extension direction of the second slide rail is defined as the Y-axis, and the extension direction of the third slide rail is defined as the Z-axis. In the X-axis direction, the second slide rail can slide along the extension direction of the first slide rail to absorb the reaction force in the X-axis direction; in the Y-axis direction, the third slide rail can slide along the extension direction of the second slide rail to absorb the reaction force in the Y-axis direction; in the Z-axis direction, the third slide rail can also slide along the extension direction of the third slide rail relative to the second slide rail to absorb the reaction force in the Z-axis direction. At the same time, a gravity balancer is always used to balance the force in the direction of gravity, that is, the Z-axis; thus, the alarm caused by the reaction force of the tightening shaft during the operation of the collaborative robot can be avoided.

[0013] In some embodiments, a slider assembly is connected between the third slide rail and the second slide rail, and the slider assembly includes a first sliding part slidably connected to the second slide rail and a second sliding part slidably connected to the third slide rail, and the first sliding part and the second sliding part are connected to form an L-shaped structure.

[0014] In some embodiments, one end of the gravity balancer is connected to the second sliding portion, and the other end is connected to the mounting plate.

[0015] In some embodiments, the gravity balancer is a balancing cylinder.

[0016] In some embodiments, the visual guidance mechanism includes a light source assembly and an image collector, wherein the light source assembly is used to provide light source for the image collector; the image collector is fixed to the mounting plate and connected to the collaborative robot signal, and is used to collect images and guide the movement of the collaborative robot according to the images.

[0017] In some embodiments, there are two of the gravity balancer, the second slide rail and the third slide rail, and one gravity balancer, one second slide rail and one third slide rail form a reaction force compensation group, and each of the third slide rails in the reaction force compensation group is provided with one of the tightening mechanisms, one of the collaborative robots and one of the visual guidance mechanisms.

[0018] In some embodiments, the bolt tightening device further includes a conveying mechanism and a positioning mechanism;

[0019] The workpiece conveyed by the conveying mechanism has a tightening station relative to the frame;

[0020] The positioning mechanism is used to fix the workpiece when the conveying mechanism conveys the workpiece to the tightening station, so that the workpiece is fixed relative to the frame.

[0021] In some embodiments, the positioning mechanism includes a positioning pin and a positioning drive, and the positioning drive is drivingly connected to the positioning pin and is used to drive the positioning pin to be inserted into the positioning hole on the workpiece.

[0022] In some embodiments, the bolt tightening device further includes a feeding mechanism;

[0023] The feeding mechanism includes a circular vibration feeder, a vertical vibration feeder and a distributor along the bolt feeding direction;

[0024] The material distributor is used to transport the bolts to the material taking station of the tightening shaft.

[0025] In some embodiments, the bolt tightening device further includes a centralized controller, which is signal-connected to the tightening mechanism, the collaborative robot, and the visual guidance mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A three-dimensional diagram of a bolt tightening device provided by an embodiment of the utility model;

[0027] Figure 2 A schematic diagram of the structure of one side of a bolt tightening device provided by an embodiment of the utility model;

[0028] Figure 3 An enlarged view of a reaction force offsetting mechanism in a bolt tightening device provided in an embodiment of the utility model;

[0029] Figure 4 and Figure 5 A schematic diagram of the structure of a reaction force offsetting mechanism in a bolt tightening device provided by an embodiment of the utility model;

[0030] Figure 6 A three-dimensional stereogram of another bolt tightening device provided by an embodiment of the utility model;

[0031] Figure 7 A schematic diagram of the structure of a conveying mechanism in another bolt tightening device provided by an embodiment of the utility model;

[0032] Figure 8 A schematic structural diagram of a positioning mechanism in another bolt tightening device provided by an embodiment of the utility model;

[0033] Fig. 9 A perspective view of a positioning mechanism in another bolt tightening device provided by an embodiment of the utility model;

[0034] Fig.10 A structural schematic diagram of a feeding mechanism in another bolt tightening device provided by an embodiment of the utility model;

[0035] Fig.11 for Fig.10 Enlarged view of the middle distributor;

[0036] Fig.12 A schematic diagram of one side structure of a feeding mechanism in another bolt tightening device provided by an embodiment of the utility model;

[0037] Fig.13 for Fig.12 Enlarged view of the middle distributor;

[0038] Fig.14 A control principle diagram of another bolt tightening device provided by an embodiment of the utility model;

[0039] Icons: 100-frame; 300-tightening mechanism; 400-collaborative robot; 500-visual guidance mechanism; 700-feeding mechanism; 800-centralized controller; 210-gravity balancer; 220-first slide rail; 230-second slide rail; 240-third slide rail; 250-slider assembly; 310-mounting plate; 320-tightening shaft; 510-light source assembly; 520-image collector; 610-conveyance mechanism; 620-positioning mechanism; 621-positioning pin; 622-pin sleeve; 623-positioning drive; 710-circular vibration feeder; 720-straight vibration feeder; 730-distributor; 740-linear silo; 251-first sliding part; 252-second sliding part; 731-distributor drive; 732-push plate. DETAILED DESCRIPTION

[0040] The following will combine the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model. Among them, in the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" refers to two or more than two.

[0041] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, unless otherwise specified, "plurality" means two or more.

[0042] like Figures 1 to 5 As shown, the embodiment of the utility model provides a bolt tightening device, including: a frame 100; a reaction force offsetting mechanism, including a gravity balancer 210 and a first slide rail 220, a second slide rail 230 and a third slide rail 240 extending in a direction perpendicular to each other; the first slide rail 220 is fixed to the frame 100, the second slide rail 230 is slidably mounted on the first slide rail 220, and the third slide rail 240 is slidably mounted on the second slide rail 230; a tightening mechanism 300, including a mounting plate 310 and a tightening member fixed to the mounting plate 310 The tightening shaft 320 and the mounting plate 310 are fixedly arranged on the third slide rail 240; the gravity balancer 210 is connected to the mounting plate 310 for absorbing the force acting in the direction of gravity; the collaborative robot 400 is connected to the tightening shaft 320 by signal for driving the tightening shaft 320 to rotate; the operating end of the collaborative robot 400 is connected to the mounting plate 310 for driving the mounting plate 310 to move relative to the frame 100; the visual guide mechanism 500 is connected to the collaborative robot 400 by signal for guiding the collaborative robot 400 to move.

[0043] The bolt tightening device provided by the present application uses a visual guidance mechanism 500 to guide the action of the collaborative robot 400, and the collaborative robot 400 automatically drives the tightening shaft 320 to tighten the bolts, avoiding the manual use of pneumatic tightening tools to tighten the bolts. This manual tightening method has labor intensity, low production efficiency, poor process stability, and quality problems such as incorrect and missing bolt assembly, and the product quality is not controlled. Therefore, the present application uses a visual guidance robot to accurately tighten and ensure the consistency of assembly.

[0044] And, if Figure 1 and Figure 2As shown, the collaborative robot 400 is installed on the frame 100 by hoisting. Since the load of the collaborative robot 400 is small, the tightening shaft 320 will generate a reaction force during the tightening process, which is directly fed back to the collaborative robot 400, causing an alarm during the movement of the robot. However, the present application sets a reaction force offset mechanism so that the collaborative robot 400 only needs to move the coordinates to complete the bolt tightening process. For ease of explanation, the extension direction of the first slide rail 220 is defined as the X-axis, the extension direction of the second slide rail 230 is defined as the Y-axis, and the extension direction of the third slide rail 240 is defined as the Z-axis. In the X-axis direction, the second slide rail 230 can slide along the extension direction of the first slide rail 220 to absorb the reaction force in the X-axis direction; in the Y-axis direction, the third slide rail 240 can slide along the extension direction of the second slide rail 230 to absorb the reaction force in the Y-axis direction; in the Z-axis direction, the third slide rail 240 can also slide along the extension direction of the third slide rail 240 relative to the second slide rail 230 to absorb the reaction force in the Z-axis direction. At the same time, the gravity balancer 210 is always used to balance the force in the direction of gravity, i.e., the Z-axis; thereby, the alarm caused by the reaction force of the tightening shaft 320 during the operation of the collaborative robot 400 can be avoided.

[0045] In some embodiments, a slider assembly 250 is connected between the third slide rail 240 and the second slide rail 230. The slider assembly 250 includes a first sliding portion 251 slidably connected to the second slide rail 230 and a second sliding portion 252 slidably connected to the third slide rail 240. The first sliding portion 251 and the second sliding portion 252 are connected to form an L-shaped structure.

[0046] One possible way to achieve this is as follows: Figure 4 and Figure 5 As shown, a slider assembly 250 is connected between the third slide rail 240 and the second slide rail 230, a first sliding portion 251 of the slider assembly 250 is slidably connected to the second slide rail 230, a second sliding portion 252 is slidably connected to the second slide rail 230 on one side, and slidably connected to the third slide rail 240 on the other side. In other words, the slider assembly 250 slides along the Y axis relative to the second slide rail 230, and the third slide rail 240 slides along the Z axis relative to the slider assembly 250. Exemplarily, the slider assembly 250 includes an L-shaped plate, a short side of the L-shaped plate having a first slider slidably connected to the second slide rail 230, a long side of the L-shaped plate having a second slider slidably connected to the second slide rail 230, and a long side of the L-shaped plate facing away from the second slider having a third slider slidably connected to the third slide rail 240. The L-shaped plate is slidably connected to the second slide rail 230 via the vertically arranged first and second sliders, thereby ensuring the verticality of the third slider and further ensuring the verticality of the third slide rail 240, so that the extension direction of the third slide rail 240 is parallel to the Z axis.

[0047] In some embodiments, one end of the gravity balancer 210 is connected to the second sliding portion 252 , and the other end is connected to the mounting plate 310 .

[0048] It should be noted that the gravity balancer 210 needs to balance the force in the direction of gravity, i.e., the Z-axis. The gravity balancer 210 needs to slide with the slider assembly 250 relative to the second slide rail 230, so one end of the gravity balancer 210 is fixed to the L-shaped plate of the slider assembly 250, and the other end of the gravity balancer 210 is connected to the mounting plate 310 fixed to the end of the third slide rail 240, thereby absorbing the force in the Z-axis direction. The main function of the gravity balancer 210 is to absorb the force in the Z-axis direction, so any structure that can achieve the above function can be used as the gravity balancer 210 in this embodiment, such as a balancing cylinder.

[0049] In some embodiments, the gravity balancer 210 is a balancing cylinder. The supporting force of the balancing cylinder is used to offset the gravity of the collaborative robot 400 and the tightening mechanism 300. When the collaborative robot 400 moves downward to tighten, its pressure increases, giving the balancing cylinder an upward reaction force, and the excess pressure is discharged from the pressure reducing valve. When moving upward, the opposite is true, so that the collaborative robot 400 can reach a balanced state when moving.

[0050] In some embodiments, the visual guidance mechanism 500 includes a light source assembly 510 and an image collector 520. The light source assembly 510 is used to provide light for the image collector 520. The image collector 520 is fixed to the mounting plate 310 and is connected to the collaborative robot 400 by signal, and is used to collect images and guide the collaborative robot 400 to move according to the images.

[0051] In one possible implementation, the light source assembly 510 and the image collector 520 are both fixed to the mounting plate 310, that is, the tightening shaft 320 and the image collector 520 move synchronously, and the relative position between the two is fixed. The image collector 520 can collect image information of the workpiece, and can also collect image information of the bolt, so as to determine the matching operation process and guide the collaborative robot 400 to move, such as the collaborative robot 400 drives the tightening shaft 320 to move to the material picking station to absorb the bolt, or the collaborative robot 400 drives the tightening shaft 320 to move to the tightening station to tighten the bolt on the workpiece. Exemplarily, the image collector 520 is a camera. The light source assembly 510 always moves synchronously with the image collector 520 to provide a light source for the image collector 520.

[0052] In some embodiments, there are two gravity balancers 210, two second slide rails 230 and two third slide rails 240, and one gravity balancer 210, one second slide rail 230 and one third slide rail 240 form a reaction force compensation group, and a tightening mechanism 300, a collaborative robot 400 and a visual guidance mechanism 500 are provided on the third slide rail 240 in each reaction force compensation group.

[0053] In one possible implementation, a workpiece such as an oil pan needs to be equipped with multiple bolts. The bolt tightening device provided in this embodiment uses two sets of tightening mechanisms 300 to work simultaneously, thereby improving work efficiency and saving process time. Figure 1 As shown, two collaborative robots 400 are hoisted on the top of the rack 100, each collaborative robot 400 is connected to a set of tightening mechanisms 300, and the two collaborative robots 400 are arranged along the X-axis and share a set of first slide rails 220. There are two first slide rails 220, and the two first slide rails 220 are arranged on the rack 100 along the Y-axis direction. Two second slide rails 230 are slidably arranged between the two first slide rails 220, and the two second slide rails 230 are independent of each other. Each second slide rail 230 is slidably connected to a third slide rail 240, and is equipped with a set of tightening mechanisms 300. One collaborative robot 400 drives one tightening mechanism 300 to achieve action in three-dimensional directions and complete the bolt tightening operation.

[0054] In some embodiments, the bolt tightening device also includes a conveying mechanism 610 and a positioning mechanism 620; the workpiece conveyed by the conveying mechanism 610 has a tightening station relative to the frame 100; the positioning mechanism 620 is used to fix the workpiece when the conveying mechanism 610 conveys the workpiece to the tightening station so that the workpiece is fixed relative to the frame 100.

[0055] In order to facilitate mechanized management and save labor, Figure 6 As shown, the bolt tightening device also includes a conveying mechanism 610 and a positioning mechanism 620; the workpiece, such as an oil pan, is conveyed to the bottom of the tightening mechanism 300 via a tray on the conveying mechanism 610, that is, it is in the tightening position; in order to keep the workpiece in the tightening position during the bolt tightening operation, the present embodiment also uses the positioning mechanism 620 to relatively fix the tray and the workpiece to the frame 100. Exemplarily, the conveying mechanism 610 can be a conveying structure such as a conveying roller or a conveying belt. Figure 6 and Figure 7 As shown, the conveying mechanism 610 is a conveying roller structure, and the workpiece such as an oil pan is fixed on a tray. The conveying roller drives the tray to transport the workpiece along the Y axis.

[0056] In some embodiments, the positioning mechanism 620 includes a positioning pin 621 and a positioning drive 623 . The positioning drive 623 is in driving connection with the positioning pin 621 and is used to drive the positioning pin 621 to be inserted into the positioning hole on the workpiece.

[0057] One possible way to achieve this is as follows: Figure 8 and Fig. 9 As shown, the positioning mechanism 620 includes a positioning pin 621 and a positioning drive 623. The positioning drive 623 can drive the positioning pin 621 to move along the Z axis to insert into the positioning hole on the pallet or to escape from the positioning hole on the pallet. Specifically, the positioning mechanism 620 also includes a pin sleeve 622. The positioning pin 621 can extend out of the pin sleeve 622 under the action of the positioning drive 623 to insert into the positioning hole at the bottom of the pallet, and can also retract into the pin sleeve 622 under the action of the positioning drive 623 to avoid interfering with the transportation of the pallet. Exemplarily, the positioning drive 623 can be a cylinder, a hydraulic cylinder or an electric push rod. In order to ensure the stable position of the pallet, there are two positioning mechanisms 620, and the two positioning mechanisms 620 are arranged along the X direction to avoid the positioning mechanism 620 causing the pallet to shift position.

[0058] In some embodiments, the bolt tightening device also includes a feeding mechanism 700; the feeding mechanism 700 includes a circular vibration feeder 710, a vertical vibration feeder 720 and a distributor 730 along the bolt conveying direction; the distributor 730 is used to convey the bolts to the material taking station of the tightening shaft 320.

[0059] In order to facilitate mechanized management and save labor, Figure 6 As shown, the bolt tightening device also includes a feeding mechanism 700 for feeding bolts. Figure 10-13 As shown, the feeding mechanism 700 includes a linear hopper 740, a circular vibration feeder 710, a straight vibration feeder 720 and a distributor 730. Workers can place bolts in the linear hopper 740, and the bolts in the linear hopper 740 enter the circular vibration feeder 710 and the straight vibration feeder 720 in sequence and then enter the distributor 730 in a straight line. Fig.11 and Fig.13 As shown, the material distributor 730 includes a material distributor drive 731 and a push plate 732, and the material distributor drive 731 is in transmission connection with the push plate 732, and is used to push the bolts to the material taking station Q. Exemplarily, the material distributor drive 731 can be a material distributor cylinder, a hydraulic cylinder or an electric push rod. Fig.13 As shown, the conveying direction of the bolts entering the distributor 730 is perpendicular to the movement direction of the push plate 732.

[0060] In one possible implementation method, bolts and support blocks are manually added into the linear silo 740. The linear silo 740, such as a belt-type silo, pushes the workpiece onto the circular vibrating feeder 710. When the lack of material detection switch installed on the linear silo 740 detects that there is a lack of material inside the linear silo 740, a signal is sent to prompt the operator to replenish the material in time. The belt-type silo drives the belt through the motor to push the bolts to the circular vibrating feeder 710; the circular vibrating feeder 710 adjusts the posture and sorts the bolts through the identification area, and sends them out in one column. The vertical state is qualified material. , it can pass normally. The material shortage switch installed on the circular vibrating feeder 710 detects that there is a shortage of material on the track, and then notifies the belt-type silo to feed the material. The circular vibrating feeder 710 pushes the bolts to the straight vibrating feeder 720 through vibration action; the straight vibrating feeder 720 sends the bolts sent from the circular vibrating feeder 710 out of the material channel one by one, and 1 column of material is discharged. When the material full detection switch installed on the straight vibrating feeder 720 is full of material, it notifies the circular vibrating feeder 710 to stop feeding, and the material dividing cylinder drives the pushing plate 732 to push the bolts to the material taking position Q for precise positioning.

[0061] In some embodiments, to facilitate automated management, such as Fig.14 As shown, the bolt tightening device further includes a centralized controller 800, and the centralized controller 800 is signal-connected to the tightening mechanism 300, the collaborative robot 400, and the visual guidance mechanism 500. The centralized controller 800 may specifically be a PLC (Programmable Logic Controller).

[0062] In one possible implementation, the workpiece is transported to the tightening station by the conveying mechanism, and the positioning mechanism positions the tray; the centralized controller sends an action guidance signal based on the information fed back by the visual guidance mechanism to guide the collaborative robot to move. The collaborative robot receives the guidance signal in real time and drives the tightening mechanism to move to the material picking station. The collaborative robot notifies the tightening shaft to rotate and pick up the bolt. After the tightening shaft picks up the bolt, it feeds back to the collaborative robot; the collaborative robot receives the guidance signal in real time and drives the tightening mechanism to move to the tightening station. The collaborative robot notifies the tightening shaft to rotate and tighten the bolt to complete the tightening operation.

[0063] In some embodiments, the bolt tightening device further includes a radio frequency identifier installed on the conveying mechanism for identifying information of the workpiece. The radio frequency identifier is connected to the collaborative robot signal. A code block carrying workpiece information such as machine model information is provided on the workpiece tray. The radio frequency identifier can identify the information code block and compare it with the information in the database to move the coordinates of the collaborative robot or replace the tightening mechanism.

[0064] In one possible implementation method, this embodiment uses collaborative robots, visual guidance technology, RFID (Radio Frequency Identification) technology, database and other technologies to design and develop a collaborative robot oil pan bolt tightening device based on visual guidance, which mainly includes a visual guidance mechanism, a tightening mechanism, a three-dimensional reaction force offset mechanism in space, a radio frequency identifier, a positioning mechanism, a database and an electrical control part. It has an error-proofing function and is linked with the line body to achieve a new technological breakthrough. The line body here can be understood as a conveying mechanism. Due to space limitations, a collaborative robot inverted hanging solution is adopted, and the model is identified with the help of a radio frequency identifier. The visual guidance collaborative robot is used to accurately tighten to ensure the consistency of assembly.

[0065] The positioning cylinder in the positioning mechanism extends to drive the positioning pin to insert into the positioning hole of the pallet to position the pallet. At the same time, the bottom radio frequency identifier such as the read-write head reads the diesel engine information on the code block at the bottom of the pallet to determine the model, read the MES (Manufacturing Execution System) information, and transmit it to the PLC to select the tightening and bolt grabbing program.

[0066] The working principle of the automatic assembly of the bolt tightening device provided in this embodiment is: when the pallet arrives at the working position, namely the tightening position, the radio frequency identifier obtains the diesel engine information, the PLC calls different tightening programs through comparison, the collaborative robot moves to the photo taking position according to the feedback value of the radio frequency identifier, the two cameras take pictures respectively, the camera calculates the workpiece offset and the offset angle and feeds them back to the PLC, the PLC guides the collaborative robot to perform position compensation according to the numerical calculation, controls the mechanical arm to move in a straight line along the XYZ axis through communication codes and instructions, and the visual guidance mechanism of the arm automatically identifies the bolts, calls different tightening parameters to tighten the bolts one by one to the preset torque, so that the device can realize differentiated automatic tightening for a variety of models, and the overall beat control is completed within 90 seconds.

[0067] In the actual assembly process of diesel engines, due to different user requirements for products, mixed assembly of multiple varieties of threaded connectors is bound to occur in production. The irregular distribution of threaded connector bolts and different tightening processes result in the need to frequently adjust the bolt tightening process in similar assembly methods. At present, most companies use manual pneumatic tightening tools to tighten bolts. This working method has labor intensity, low production efficiency, poor process stability, and quality problems such as wrong and missed assembly of bolts, and the product quality is not controlled. This embodiment takes the flexible control of bolt tightening as the entry point, and organically combines PLC, collaborative robots, radio frequency identifiers, visual cameras, tightening shafts, and conveyor rollers in a distributed control manner to form an integrated control system, which can make up for the shortcomings of traditional bolt tightening methods, and can accurately monitor the bolt tightening process in real time, realizing the automated assembly of different threaded connectors of diesel engines, making the production line flexible, improving production efficiency, and achieving the effect of reducing production costs.

[0068] The system on which the bolt tightening device provided in this embodiment relies mainly includes four modules: work interface, data query, adding order number, and manual operation. And the normal numerical curve of the parameter is fitted by data, compared with the actual curve, and the status of each parameter is monitored in real time. The assembly information of each engine component is automatically saved in the background database. The saved information includes part number, order number, actual tightening torque, equipment tightening program number, and assembly time of the part. When the engine is assembled by the equipment, the system automatically prompts that the engine has been assembled for the second time. There are two main query methods for this software. You can query according to the order number or according to the date. The information of each unit is automatically saved to facilitate future product tracing.

[0069] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A bolt tightening device, It is characterized in that include: frame; The reaction force offset mechanism comprises a gravity balancer and a first slide rail, a second slide rail and a third slide rail, the extension directions of which are perpendicular to each other; the first slide rail is fixed to the frame, the second slide rail is slidably mounted on the first slide rail, and the third slide rail is slidably mounted on the second slide rail; The tightening mechanism comprises a mounting plate and a tightening shaft fixed to the mounting plate, the mounting plate is fixed to the third slide rail, and the gravity balancer is connected to the mounting plate to absorb the force in the direction of gravity; The collaborative robot is connected to the tightening shaft signal and is used to drive the tightening shaft to rotate; the operating end of the collaborative robot is connected to the mounting plate and is used to drive the mounting plate to move relative to the frame; The visual guidance mechanism is connected to the collaborative robot signal and is used to guide the collaborative robot to move.

2. The bolt tightening device according to claim 1, It is characterized in that A slider assembly is connected between the third slide rail and the second slide rail. The slider assembly includes a first sliding portion slidably connected to the second slide rail and a second sliding portion slidably connected to the third slide rail. The first sliding portion and the second sliding portion are connected to form an L-shaped structure.

3. The bolt tightening device according to claim 2, It is characterized in that One end of the gravity balancer is connected to the second sliding part, and the other end is connected to the mounting plate.

4. The bolt tightening device according to claim 1, It is characterized in that The gravity balancer is a balancing cylinder.

5. The bolt tightening device according to claim 1, It is characterized in that The visual guidance mechanism includes a light source assembly and an image collector, wherein the light source assembly is used to provide light source for the image collector; the image collector is fixed to the mounting plate and connected to the collaborative robot signal, and is used to collect images and guide the collaborative robot to move according to the images.

6. The bolt tightening device according to claim 1, It is characterized in that There are two of the gravity balancer, the second slide rail and the third slide rail, and one gravity balancer, one second slide rail and one third slide rail form a reaction force compensation group. The third slide rail in each reaction force compensation group is provided with one of the tightening mechanisms, one of the collaborative robots and one of the visual guidance mechanisms.

7. The bolt tightening device according to any one of claims 1 to 6, It is characterized in that The bolt tightening device also includes a conveying mechanism and a positioning mechanism; The workpiece conveyed by the conveying mechanism has a tightening station relative to the frame; The positioning mechanism is used to fix the workpiece when the conveying mechanism conveys the workpiece to the tightening station, so that the workpiece is fixed relative to the frame.

8. The bolt tightening device according to claim 7, It is characterized in that The positioning mechanism comprises a positioning pin and a positioning drive, wherein the positioning drive is drivingly connected to the positioning pin and is used for driving the positioning pin to be inserted into the positioning hole on the workpiece.

9. The bolt tightening device according to any one of claims 1 to 6, It is characterized in that The bolt tightening device also includes a feeding mechanism; The feeding mechanism includes a circular vibration feeder, a vertical vibration feeder and a distributor along the bolt feeding direction; The material distributor is used to transport the bolts to the material taking station of the tightening shaft.

10. The bolt tightening device according to any one of claims 1 to 6, It is characterized in that The bolt tightening device also includes a centralized controller, which is signal-connected to the tightening mechanism, the collaborative robot, and the visual guidance mechanism.

Images