A device for automatically tightening nuts

Abstract

The application discloses a device for automatically screwing nuts, which comprises a base, a support, a sliding block, an electric or pneumatic wrench, a tension spring, a lifting action executor, a nut screwing-in position detector and a controller; the support is vertically installed on the base, the sliding block is slidingly installed on the support, the electric or pneumatic wrench is installed on the sliding block, and a nut sleeve is installed on the output rotating shaft of the electric or pneumatic wrench; the lifting action executor is used for driving the sliding block to ascend, the tension spring is used for providing a downward tension force for the sliding block, the electric or pneumatic wrench on the sliding block has a downward flexible pressure when the action rod of the lifting action executor descends under the action of the downward tension force of the tension spring; the nut screwing-in position detector is installed on the sliding block, and the controller judges whether the electric or pneumatic wrench on the sliding block screws the nut to the position according to the detection information of the nut screwing-in position detector. The device can automatically complete the working cycle of nut screwing-in, screwing-tightening and screwing-out, and can judge whether the nut is screwed to the position in each working cycle, thereby omitting the intermediate manual operation link.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mechanical assembly, in particular to a device for automatically tightening nuts. BACKGROUND

[0002] In the automobile manufacturing industry and other industries, there are many parts that need to be tightened with nuts, and nut and bolt pairing is also the most common fixing method. Figure 1 A bolt 32 is arranged on a workpiece 31, and a nut 33 needs to be tightened on the bolt 32 of the workpiece 31. At present, the commonly used method for tightening the nut is a pneumatic or electric wrench tool. When using, the user first holds the nut on the bolt and rotates it at least one circle to ensure that the nut is embedded with the bolt, then the sleeve of the pneumatic or electric wrench tool is sleeved into the nut, the switch is pulled, the hand is followed by the nut rotation, and the work is stopped after reaching the set torque. Finally, the user manually takes out the tool and the workpiece. This nut assembly method is relatively cumbersome, and the efficiency needs to be improved. SUMMARY

[0003] The purpose of the present application is to overcome the shortcomings of the prior art, provide a device for automatically tightening nuts, which can automatically complete the work cycle of nut rotation-tightening-exit, and judge whether the nut is tightened in place in each work cycle, thereby eliminating the intermediate manual operation link.

[0004] The present application is realized by the following technical solutions:

[0005] A device for automatically tightening nuts, comprising a base, a bracket, a sliding block, an electric or pneumatic wrench, a nut sleeve, a tension spring, a lifting action executor, a nut tightening in place detector and a controller;

[0006] The bracket is vertically installed on the base, and the sliding block is slidingly installed on the bracket. A workpiece mounting seat is arranged on the base;

[0007] The electric or pneumatic wrench is installed on the sliding block, and the output shaft of the electric or pneumatic wrench is arranged downward. The nut sleeve is installed on the output shaft, and the bottom end of the nut sleeve is provided with a nut mounting hole for mounting the nut. The electric or pneumatic wrench is connected with the controller, and the work of the electric or pneumatic wrench is controlled by the controller;

[0008] The lifting action executor is connected with the controller and is used to drive the sliding block to rise;

[0009] The tension spring is used to provide a downward tension for the sliding block. When the action rod of the lifting action executor descends, the electric or pneumatic wrench on the sliding block has a downward flexible pressure under the action of the downward tension of the tension spring;

[0010] The nut screwing-to-position detector is installed on the sliding block, the nut screwing-to-position detector is connected with the controller, the nut screwing-to-position detector is used for detecting the position condition of the downward operation of the sliding block, and the controller judges whether the electric or pneumatic wrench on the sliding block screws the nut to the position according to the detection information of the nut screwing-to-position detector.

[0011] In the technical scheme, the workpiece mounting seat is provided with a positioning mounting groove for placing the workpiece.

[0012] In the technical scheme, the elastic insert is arranged on the inner wall of the nut mounting hole, and when the nut is mounted into the nut mounting hole, the elastic insert can abut against the nut, so that the nut can overcome its own gravity and be kept in the nut mounting hole without falling.

[0013] In the technical scheme, the lifting action executor is located at the back of the support, the sliding block is installed at the front of the support, a connecting frame is arranged at the top rear side of the sliding block, and the action rod of the lifting action executor can abut against the connecting frame, so as to drive the sliding block to ascend.

[0014] In the technical scheme, the nut screwing-to-position detector adopts a contact switch or a distance measuring sensor.

[0015] In the technical scheme, the support is installed on the base through a support seat, the X-direction and Y-direction installation positions of the support seat on the base are adjustable, and the bolts on the nut sleeve and the workpiece on the workpiece mounting seat are in coaxial relationship by adjusting the support seat.

[0016] In the technical scheme, the lifting action executor is installed on the support seat, the bottom end of the tension spring is connected to the support seat, and the top end of the tension spring is connected to the sliding block.

[0017] In the above technical solution, the support seat comprises a lower plate and an upper plate, the lower plate is installed on the base through first bolts, the installation holes of the first bolts on the lower plate are long strip-shaped installation holes along the X direction, a first side plate is arranged on the side of the lower plate along the X direction, the first side plate is fixed on the base, and X-direction bolt holes along the X direction are arranged on the first side plate, when the X-direction position of the support seat needs to be adjusted, the first bolts on the lower plate are loosened first, then the X-direction jacking bolts in the X-direction bolt holes of the first side plate are adjusted, the X-direction position of the lower plate is adjusted by adjusting the screwing depth of the X-direction jacking bolts, after the position is adjusted to a proper position, the first bolts on the lower plate are tightened again to lock the position; the upper plate is installed on the lower plate through second bolts, the installation holes of the second bolts on the upper plate are long strip-shaped installation holes along the Y direction, a second side plate is arranged on the side of the upper plate along the Y direction, the second side plate is fixed on the lower plate, and Y-direction bolt holes along the Y direction are arranged on the second side plate, when the Y-direction position of the support seat needs to be adjusted, the second bolts on the upper plate are loosened first, then the Y-direction jacking bolts in the Y-direction bolt holes of the second side plate are adjusted, the Y-direction position of the upper plate is adjusted by adjusting the screwing depth of the Y-direction jacking bolts, after the position is adjusted to a proper position, the second bolts on the upper plate are tightened again to lock the position.

[0018] In the above technical solution, the controller is further connected with a man-machine interaction panel, the number of times of tightening the nut is displayed through the man-machine interaction panel, and the judgment result of whether the nut is tightened to the position is displayed.

[0019] The use method of the device for automatically tightening the nut is as follows:

[0020] Step 1, first, the device is in an initial state, in this state, the action rod of the lifting action executor is in an elongated state, the workpiece is placed on the workpiece mounting seat, and the nut is embedded into the nut sleeve;

[0021] Step 2, after the start button is pressed, the controller controls the action rod of the lifting action executor to descend to a set position, and starts the electric or pneumatic wrench to drive the nut sleeve to rotate, under the downward pulling force of the tension spring, the electric or pneumatic wrench on the sliding block has a downward flexible pressure, so that the nut in the nut sleeve is screwed into the bolt on the workpiece, and the nut is tightened until the nut is tightened; after the nut is tightened, the electric or pneumatic wrench is automatically stopped, after the controller receives the stop signal of the electric or pneumatic wrench, whether the nut is tightened to the position is judged according to the detection information of the nut tightening to the position detector, and the action rod of the lifting action executor is elongated to the initial state, so that the nut sleeve exits the workpiece;

[0022] Step 3, the workpiece with the tightened nut on the workpiece mounting seat is taken out.

[0023] The advantages and beneficial effects of the present application are as follows.

[0024] The lifting action executor and the wrench part of the present application are not rigidly connected together, and only the wrench part is lifted up during lifting, and the present application provides downward pulling force by a tension spring to make the electric or pneumatic wrench on the sliding block have downward flexible pressure, and further make the rotation speed of the nut sleeve and the screw pitch of the nut match the downward speed when the electric or pneumatic wrench drives the nut sleeve to rotate, and the tension spring can ensure the downward flexible pressure in a large adaptive range until the nut is tightened.

[0025] The conventional process is to manually visually judge the nut sleeve into the bolt and manually rotate at least one circle to ensure that the nut is not dislocated. The present application can adjust the X and Y directions of the nut sleeve of the electric or pneumatic wrench by setting the X and Y direction adjustable support seat, so that the bolt on the workpiece on the nut sleeve and the workpiece mounting seat are in coaxial relationship.

[0026] The present application can automatically complete the work cycle of nut rotation-in-tight-out, and judge whether the nut is tightened in place in each work cycle, and save the intermediate manual operation link. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a schematic diagram for nut and workpiece assembly.

[0028] Figure 2 It is a structure schematic diagram of the front view of the automatic nut tightening device of the present application.

[0029] Figure 3 It is a use state diagram of the nut sleeve in the present application.

[0030] Figure 4 It is a structure schematic diagram of the back view of the automatic nut tightening device of the present application.

[0031] Figure 5 It is a schematic diagram of the lifting action executor of the automatic nut tightening device of the present application, and the connecting frame on the action lever and the sliding block are not rigidly connected.

[0032] For ordinary skilled persons in the art, other related drawings can be obtained according to the above drawings without creative labor. DETAILED DESCRIPTION

[0033] In order to make the personnel in the technical field better understand the present application scheme, the technical scheme of the present application will be further described below in combination with specific embodiments.

[0034] Referring to the drawings Figure 2 -Appendix Figure 5The utility model provides a device of automatic screwing nut, including base 1, support seat 2, support 3, sliding block 4, electric or pneumatic wrench 5, nut sleeve 6, tension spring 7, lifting action executor 8, nut screwing to position detector 9 and controller 10.

[0035] Support seat 2 is installed on base 1, and support 3 is vertically installed on support seat 2, and vertical slide rails are arranged on support 3, and sliding block 4 is slidably installed on support 3 in cooperation with the slide rails and can slide up and down.

[0036] Electric or pneumatic wrench 5 is installed on sliding block 4 and moves synchronously with the sliding block, and the output rotating shaft of electric or pneumatic wrench 5 is downwardly arranged, and nut sleeve 6 is installed on the output rotating shaft of electric or pneumatic wrench 5, as shown in the accompanying drawings. Figure 3 The bottom end of nut sleeve 6 is provided with a nut mounting hole 6.1 for mounting a nut, and an elastic insert 6.11 is arranged on the inner wall of the nut mounting hole 6.1, which can abut against the nut 33 when the nut 33 is installed in the nut mounting hole 6.1, so that the nut 33 can be kept in the nut mounting hole 6.1 against its own gravity without falling. Further, electric or pneumatic wrench 5 is connected with the controller, and the controller controls the work of electric or pneumatic wrench 5.

[0037] Lifting action executor 8 is installed on support seat 2 and is used to drive sliding block 4 to rise, and further, lifting action executor 8 is located at the back of support 3, and sliding block 4 is installed at the front of support 3, and a connecting frame 12 is arranged at the top rear side of sliding block 4, which is preferably U-shaped, and the action rod 8.1 of lifting action executor 8 can abut against the connecting frame 12, so as to drive sliding block 4 to rise.

[0038] The bottom end of tension spring 7 is connected with support seat 2, and the top end of tension spring 7 is connected with the connecting frame 12 on sliding block 4. Tension spring 7 is used to provide downward tension to sliding block 4, and when the action rod 8.1 of lifting action executor 8 descends, the downward tension of tension spring 7 can make sliding block 4 and electric or pneumatic wrench 5 on sliding block 4 have flexible pressure downwardly, so that when electric or pneumatic wrench 5 drives nut sleeve 6 to rotate, the rotation speed of nut sleeve 6 and the pitch of the nut can match the downward speed, and tension spring 7 can ensure the flexible pressure downwardly in a large adaptive range until the nut is screwed. Figure 5), if the action rod 8.1 of the lifting action executor 8 and the sliding block 4 are hard connected together, when the action rod 8.1 of the lifting action executor 8 is lowered, it is difficult to match the descending speed of the action rod 8.1 with the rotating speed of the nut sleeve 6, too fast rotation will increase the extra friction and cause resistance, too slow rotation will cause the nut to be loosened when the nut sleeve is tightened.

[0039] The nut tightening to position detector 9 is fixedly installed on the side wall of the sliding block 4 and moves synchronously with the sliding block, the nut tightening to position detector 9 is connected with the controller, the nut tightening to position detector 9 is used to detect the position of the sliding block 4 when it is running downward, and then the controller judges whether the nut is tightened to position by the electric or pneumatic wrench 5 on the sliding block 4 according to the detection information of the nut tightening to position detector 9. Further, the nut tightening to position detector 9 can adopt a contact switch, when the contact 9.1 of the contact switch contacts the support seat 2 below, a trigger signal is generated, if the controller receives the trigger signal, it is judged that the nut is tightened to position; if the electric or pneumatic wrench 5 stops after tightening the nut to the set torque (at this time the controller will receive the stop signal of the electric or pneumatic wrench 5), and the controller still does not receive the trigger signal, it is judged that the nut is not tightened to position, but is stuck in the middle position of the bolt. The nut tightening to position detector 9 can also adopt a distance measuring sensor, the distance measuring sensor detects the distance from the support seat 2, and the controller judges whether the nut is tightened to position according to the detection distance value of the distance measuring sensor and the set threshold value, in particular: if the detection distance value of the distance measuring sensor is less than or equal to the set threshold value, it is judged that the nut is tightened to position; if the electric or pneumatic wrench 5 stops after tightening the nut to the set torque (at this time the controller will receive the stop signal of the electric or pneumatic wrench 5), and the detection distance value of the distance measuring sensor at this time is greater than the set threshold value, it is judged that the nut is not tightened to position, but is stuck in the middle position of the bolt.

[0040] Further, the X and Y direction installation positions of the support seat 2 on the base 1 are adjustable, thereby the X and Y direction positions of the nut sleeve 6 of the electric or pneumatic wrench 5 can be adjusted, so that the nut sleeve 6 and the bolt on the workpiece on the workpiece mounting seat 11 are in coaxial relationship, the X direction refers to the longitudinal direction of the base 1, and the Y direction refers to the transverse direction of the base 1. In particular: referring to the drawings, the X and Y direction installation positions of the support seat 2 on the base 1 are adjusted by adjusting the X and Y direction positions of the support seat 2 on the base 1, and then the X and Y direction positions of the nut sleeve 6 of the electric or pneumatic wrench 5 are adjusted by adjusting the X and Y direction positions of the support seat 2 on the base 1. Figure 4, the support seat 2 comprises a lower plate 2.1 and an upper plate 2.2, the lower plate 2.1 is installed on the base 1 through four first bolts 2.12, and the mounting holes of the first bolts 2.12 on the lower plate 2.1 are long strip-shaped mounting holes along the X direction; a first side plate 2.11 is arranged on the side of the lower plate 2.1 along the X direction, the first side plate 2.11 is fixed on the base 1, and X-direction bolt holes 2.13 along the X direction are arranged on the first side plate 2.11; when the X-direction position of the support seat 2 needs to be adjusted, the first bolts 2.12 on the lower plate 2.1 are first loosened, then the X-direction jacking bolts in the X-direction bolt holes 2.13 of the first side plate 2.11 are adjusted, the X-direction position of the lower plate 2.1 is adjusted by adjusting the screwing depth of the X-direction jacking bolts (since the mounting holes of the first bolts 2.12 are long strip-shaped mounting holes along the X direction, the lower plate 2.1 can have a certain displacement along the X direction), and after being adjusted to a suitable position, the first bolts 2.12 on the lower plate 2.1 are tightened to lock the position; similarly, the upper plate 2.2 is installed on the lower plate 2.1 through four second bolts 2.22, and the mounting holes of the second bolts 2.22 on the upper plate 2.2 are long strip-shaped mounting holes along the Y direction; a second side plate 2.21 is arranged on the side of the upper plate 2.2 along the Y direction, the second side plate 2.21 is fixed on the lower plate 2.1, and Y-direction bolt holes 2.23 along the Y direction are arranged on the second side plate 2.21 (see the attached Figure 2 ), when the Y-direction position of the support seat 2 needs to be adjusted, the second bolts 2.22 on the upper plate 2.2 are first loosened, then the Y-direction jacking bolts in the Y-direction bolt holes 2.23 of the second side plate 2.21 are adjusted, the Y-direction position of the upper plate 2.2 is adjusted by adjusting the screwing depth of the Y-direction jacking bolts (since the mounting holes of the second bolts 2.22 are long strip-shaped mounting holes along the Y direction, the upper plate 2.2 can have a certain displacement along the Y direction), and after being adjusted to a suitable position, the second bolts 2.22 on the upper plate 2.2 are tightened to lock the position.

[0041] Further, the controller 10 is arranged on the base 1, the controller 10 is also connected with a man-machine interaction panel, through the man-machine interaction panel, the number of times of completing the tightening of the nut (that is, the number of workpieces on which the nut is completed to be assembled) can be displayed, a set threshold value for comparing with the detection value of the distance measuring sensor can also be set, and the judgment information whether the nut is tightened in place each time can also be displayed.

[0042] The use method and working process of the automatic nut tightening device are as follows:

[0043] Step 1, first, the device is in an initial state, in this state, the action rod 8.1 of the lifting action executor 8 is in an elongated state, and the nut sleeve 6 of the electric or pneumatic wrench 5 is far away from the workpiece mounting seat 11; the workpiece is placed on the workpiece mounting seat 11, and the nut is embedded into the nut sleeve 6.

[0044] Step 2, press the start button (the start button can be a physical button set on the base, or a virtual start button set in the human-computer interaction panel), the device automatically completes the work cycle of nut screwing-in, tightening and exiting, and judges whether the nut is tightened in place in each work cycle, and displays the judgment result on the human-computer interaction panel. Specifically, after pressing the start button, the controller controls the action rod 8.1 of the lifting action executor 8 to descend to the set position, and starts the electric or pneumatic wrench 5 to drive the nut sleeve 6 to rotate, under the downward tension of the tension spring 7, the electric or pneumatic wrench 5 on the sliding block 4 has a downward flexible pressure, and then the nut in the nut sleeve 6 screws into the bolt on the workpiece and is tightened until the nut is tightened; after the nut is tightened, the electric or pneumatic wrench 5 stops, and the controller receives the stop signal of the electric or pneumatic wrench 5, judges whether the nut is tightened in place according to the detection signal of the nut tightening in place detector 9, and controls the action rod 8.1 of the lifting action executor 8 to extend to the initial state, so that the nut sleeve 6 exits the workpiece.

[0045] Step 3, take out the workpiece with the nut tightened on the workpiece mounting seat 11.

[0046] The above is an exemplary description of the present application, it should be noted that any simple modification, modification or other equivalent replacement which can not cost creative labor of those skilled in the art without departing from the core of the present application falls within the protection scope of the present application.

Claims

1. A device for automatically tightening nuts, characterized in that: Includes base, bracket, slider, electric or pneumatic wrench, nut sleeve, tension spring, lifting actuator, nut tightening detector and controller; The bracket is vertically mounted on the base, the slider is slidably mounted on the bracket, and a workpiece mounting seat is provided on the base; The electric or pneumatic wrench is mounted on the slider, with the output shaft of the electric or pneumatic wrench facing downwards. A nut sleeve is mounted on the output shaft, and the bottom end of the nut sleeve has a nut mounting hole for installing a nut. The electric or pneumatic wrench is connected to a controller, which controls the operation of the electric or pneumatic wrench. The lifting actuator is connected to the controller and is used to drive the slider to rise; The tension spring is used to provide a downward pulling force to the slider; when the actuator rod of the lifting action descends, the downward pulling force of the tension spring causes the electric or pneumatic wrench on the slider to have a downward flexible pressure. The nut tightening detector is installed on the slider and is connected to the controller. The nut tightening detector is used to detect the downward movement of the slider. The controller determines whether the electric or pneumatic wrench on the slider has tightened the nut to the correct position based on the detection information of the nut tightening detector. The bracket is mounted on the base via a bracket seat. The X and Y directions of the bracket seat on the base are adjustable. By adjusting the bracket seat, the nut sleeve and the bolt on the workpiece on the workpiece mounting seat can be made to be coaxial. The support base includes a lower plate and an upper plate. The lower plate is mounted on the base by a first bolt, and the mounting hole for the first bolt on the lower plate is an elongated mounting hole along the X-direction. A first side plate is provided on the X-direction side of the lower plate, and the first side plate is fixed to the base. The first side plate also has an X-direction bolt hole along the X-direction. When it is necessary to adjust the X-direction position of the support base, first loosen the first bolt on the lower plate, then adjust the X-direction tightening bolt in the X-direction bolt hole of the first side plate. The X-direction position of the lower plate is adjusted by adjusting the screw depth of the X-direction tightening bolt. After adjusting to the appropriate position, tighten the first bolt on the lower plate. Locking position; the upper plate is mounted on the lower plate by a second bolt, and the mounting hole of the second bolt on the upper plate is an elongated mounting hole along the Y direction. A second side plate is provided on the Y-direction side of the upper plate, and the second side plate is fixed to the lower plate. A Y-direction bolt hole is provided on the second side plate along the Y direction. When it is necessary to adjust the Y-direction position of the bracket, first loosen the second bolt on the upper plate, and then adjust the Y-direction tightening bolt in the Y-direction bolt hole of the second side plate. The Y-direction position of the upper plate is adjusted by adjusting the screwing depth of the Y-direction tightening bolt. After adjusting to the appropriate position, tighten the second bolt on the upper plate to lock the position.

2. The device for automatically tightening nuts according to claim 1, characterized in that: The workpiece mounting base is equipped with a positioning mounting groove for placing the workpiece.

3. The device for automatically tightening nuts according to claim 1, characterized in that: An elastic insert is provided on the inner wall of the nut mounting hole. When the nut is installed into the nut mounting hole, the elastic insert can hold the nut in place, so that the nut can overcome its own weight and stay in the nut mounting hole without falling off.

4. The device for automatically tightening nuts according to claim 1, characterized in that: The lifting actuator is located on the back of the bracket, the slider is installed at the front of the bracket, and a connecting frame is provided on the rear side of the top of the slider. The actuating rod of the lifting actuator can touch the connecting frame to drive the slider to rise.

5. The device for automatically tightening nuts according to claim 1, characterized in that: The nut tightening detector uses a contact switch or a distance sensor.

6. The device for automatically tightening nuts according to claim 1, characterized in that: The lifting actuator is mounted on the bracket; the bottom end of the tension spring is connected to the bracket, and the top end of the tension spring is connected to the slider.

7. The method of using the automatic nut tightening device according to claim 1, characterized in that, Includes the following steps: Step 1: First, the device is in the initial state. In this state, the actuator rod of the lifting action is in the extended state. The workpiece is placed on the workpiece mounting seat and the nut is inserted into the nut sleeve. Step 2: After pressing the start button, the controller controls the lifting actuator's rod to descend to the set position and starts the electric or pneumatic wrench to drive the nut sleeve to rotate. Under the downward pulling force of the tension spring, the electric or pneumatic wrench on the slider has downward flexible pressure, causing the nut in the nut sleeve to screw into the bolt on the workpiece until the nut is tightened. After the nut is tightened, the electric or pneumatic wrench stops automatically. After receiving the stop signal from the electric or pneumatic wrench, the controller determines whether the nut is tightened to the correct position based on the detection information of the nut tightening detector, and controls the lifting actuator's rod to extend to the initial state, causing the nut sleeve to exit the workpiece. Step 3: Remove the workpiece with the nut tightened on the workpiece mounting base.

8. The method of using the automatic nut tightening device according to claim 7, characterized in that: The controller is also connected to a human-machine interface panel, which displays the number of times the nut has been tightened and the result of whether the nut has been tightened properly.

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