CN210210184U - Bolt fastening device capable of accurately controlling fastening torque - Google Patents

Abstract

The utility model discloses a can accurate control fastening torque's bolt-up device belongs to assembly tool technical field. The device is formed by sequentially connecting a power module, an elastic module and a fastening module in series; the power module comprises a controller, a motor and a speed reducer; the device also comprises a bolt position real-time detection module. The motor and the speed reducer provide bolt fastening torque and rotating speed, the controller controls the starting and stopping of the bolt fastening device, the fastening torque and the rotating speed, and the controller adjusts the bolt fastening torque and the rotating speed according to the position of the bolt, so that the bolt smoothly stops rotating while reaching an expected torque, the impact of a bolt head on the surface of a workpiece is reduced, and the bolt head is in smooth contact with the workpiece; therefore, the fastening torque is accurately controlled, the impact torque is reduced, and the surface of a workpiece, the screw hole internal thread or a fastening device is prevented from being damaged.

Description

Bolt fastening device capable of accurately controlling fastening torque

Technical Field

The utility model belongs to the technical field of the erecting tool, a bolt fastening device is related to, especially, relate to a bolt fastening device that can accurate control fastening torque.

Background

In the manufacturing industry, the bolt is fastened by using the power fastening device, so that the burden of people can be reduced, and the assembly efficiency can be improved. Certain fastening occasions need to accurately control bolt fastening torque and have small impact in the whole fastening process, the requirement puts high requirements on torque control of the power fastening device, and the current domestic power fastening device is difficult to realize accurate fastening torque control and further reduces overshoot on the basis.

When the power fastening device is used for fastening a bolt, the power fastening device rotates at a high speed and has larger inertia, the axial feeding speed of the bolt is suddenly reduced due to the static workpiece at the moment of contact between the bolt head and the workpiece, the kinetic energy of the bolt is instantly converted into the elastic potential energy of the bolt on the workpiece, and the workpiece is easily damaged because no buffer device is used for storing the potential energy. The existing power fastening device generally adopts a method of adding an elastic element in the axial direction to relieve the impact force in the axial direction, but still cannot completely solve the problem of the impact force and cannot effectively unload the radial rotating moment. In addition, in the process of aligning the bolt and the screw hole, deviation often exists, occasionally, thread tapping defect also can appear, cause to appear unusually in the bolt tightening process, if control is improper, can damage the screw hole internal thread, destroy equipment itself.

Since the conventional power fastening device is difficult to reduce overshoot on the basis of accurate fastening torque control, it is impossible to solve the above-mentioned technical problems, and a bolt fastening device capable of accurately controlling fastening torque is urgently required.

Disclosure of Invention

The utility model aims at providing a can accurate control fastening torque's bolt-up device, solve aforementioned technical problem. The purpose of the utility model is realized through the following technical scheme.

A bolt fastening device capable of accurately controlling fastening torque is formed by sequentially connecting a power module, an elastic module and a fastening module in series; the power module comprises a controller, a motor and a speed reducer; the device also comprises a bolt position real-time detection module. The motor and the speed reducer provide bolt fastening torque and rotating speed to drive the fastening module to fasten the bolt; the controller controls the starting and stopping of the bolt fastening device, fastening torque and rotating speed, and adjusts the bolt fastening torque and the rotating speed according to the bolt position, so that the bolt stops rotating smoothly when reaching an expected torque, the impact of the bolt head on the surface of a workpiece is reduced, and the bolt head is in smooth contact with the workpiece; therefore, the fastening torque is accurately controlled, the impact torque is reduced, and the surface of a workpiece, the screw hole internal thread or a fastening device is prevented from being damaged.

In some embodiments, the real-time bolt position detection module is a photoelectric encoder. The photoelectric encoder mainly comprises a grating disc and a photoelectric detection device, has the main working principle of photoelectric conversion, and is a sensor for converting the mechanical geometric position of an output shaft into pulse or digital quantity.

In some embodiments, the elastic module is a rubber or torsion spring. The deformation of the elastic module reflects the moment on the shaft.

In some embodiments, a cushion module is further included between the elastic module and the fastening module.

Further, the buffer module comprises a spring and a coupler, and the coupler is used for connecting two physically unconnected shafts or shafts with different specifications.

In some embodiments, the fastening modules are a batch head adapter and a batch head.

The process of the bolt-tightening apparatus to precisely control the moment and to alleviate the impact is described in detail below.

As shown in FIG. 2, on the basis of the traditional current and speed double closed loop, a torque controller is added to form a torque loop capable of accurately controlling torque. In the torque loop, Td is the desired torque and Tr is the measured torque. Tr is a moment reflected by deformation of rubber with a known elastic coefficient, i.e., Tr ═k (theta 1-theta 2). The accurate torque monitoring can ensure the final accurate torque output of the bolt fastening device, and in order to further weaken the impact injury of the device to the fastening piece, the device and a user in the dynamic transition process, the invention adds the impedance ring on the basis of the torque ring. Impedance describes the dynamic relationship of position and moment

Also can be converted into the forms of speed and moment

In the impedance loop, the input is the expected speed Vt, the feedback is the actual speed (d theta 2/dt) of the bolt head, and the design of the impedance controller is based on the setting of I, B, K parameters in the impedance relation. The resistance ring dynamically adjusts the size of the expected moment Td of the moment ring according to the actual speed (d theta 2/dt) of the bolt bit so as to achieve the effect of reducing the impact. The input of the resistance loop is an expected speed Vt, which means that the fastening device is started at the expected speed Vt, when it is detected that the external torque reaches the torque set by the user, the set speed Vt is 0, the operation of the device is stopped, and the fastening of the bolt is completed.

The speed of the bolt head is indirectly detected through an encoder, and the controller takes the speed of the bolt as the feedback input of the impedance controller; the moment controller dynamically adjusts the expected moment Td of the moment ring according to the output of the impedance controller and monitors the change of the external moment Tr in real time, so that the bolt smoothly stops rotating when reaching the expected moment, the impact of the bolt head on the surface of the workpiece is reduced, and the bolt head is smoothly contacted with the workpiece.

The utility model discloses following beneficial technological effect has: the impact force of the bolt on the workpiece is reduced when the bolt fastening device runs at a high speed, and the bolt is flexibly screwed into the screw hole to fasten the workpiece; reducing the impact on the fastening tool and the operator's arm. In the process that the bolt is screwed into the screw hole, the bolt can automatically stop when encountering the abnormal moment condition, so that the damage rate of the bolt and a workpiece is reduced; the accuracy of the bolt fastening force can be improved.

Drawings

Fig. 1 is a schematic structural view of the bolt fastening device of the present invention.

Fig. 2 is a control block diagram of the controller of the bolt fastening device of the present invention.

Reference numerals: the device comprises a motor 1, a controller 2, a speed reducer 3, a grating 4, an encoder 5, a serial elastic actuator 6, a spring 7, a coupler 8, a bit adapter 9 and a bit 10.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of some, and not necessarily all, embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1, the bolt fastening device capable of accurately controlling fastening torque provided by the present invention is composed of a power module, an elastic module, a buffer module and a fastening module which are connected in series in sequence; the power module comprises a controller 2, a motor 1 and a speed reducer 3; the device also comprises a bolt position real-time detection module. Bolt position real-time detection module includes grating 4 and encoder 5, and the elastic module is series connection elastic actuator 6, and buffer module includes spring 7 and shaft coupling 8, and fastening module is criticized first adapter 9 and criticizes first 10. The motor and the speed reducer provide bolt fastening torque and rotating speed, and the controller controls the starting and stopping of the bolt fastening device, the fastening torque and the rotating speed.

As shown in FIG. 2, on the basis of the traditional current and speed double closed loop, a torque controller is added to form a torque loop capable of accurately controlling torque. In the torque loop, Td is the desired torque and Tr is the measured torque. Tr is a moment reflected by deformation of the rubber having a known elastic coefficient, i.e., Tr ═ k (θ 1- θ 2). The accurate torque monitoring can ensure the final accurate torque output of the bolt fastening device, and in order to further weaken the impact injury of the device to the fastening piece, the device and a user in the dynamic transition process, the invention adds the impedance ring on the basis of the torque ring. Impedance describes the dynamic relationship of position and moment

Also can be converted into the forms of speed and moment

In the impedance loop, the input is the expected speed Vt, the feedback is the actual speed (d theta 2/dt) of the bolt head, and the design of the impedance controller is based on the setting of I, B, K parameters in the impedance relation. The resistance ring dynamically adjusts the size of the expected moment Td of the moment ring according to the actual speed (d theta 2/dt) of the bolt bit so as to achieve the effect of reducing the impact. The input of the resistance loop is an expected speed Vt, which means that the fastening device is started at the expected speed Vt, when it is detected that the external torque reaches the torque set by the user, the set speed Vt is 0, the operation of the device is stopped, and the fastening of the bolt is completed.

Detecting the speed of the bolt head through an encoder, and using the speed of the bolt as the feedback input of an impedance controller by a controller; the moment controller dynamically adjusts the expected moment Td of the moment ring according to the output of the impedance controller and monitors the change of the external moment Tr in real time, so that the bolt smoothly stops rotating when reaching the expected moment, the impact of the bolt head on the surface of the workpiece is reduced, and the bolt head is smoothly contacted with the workpiece.

Variations, modifications, substitutions and alterations of the above-described embodiments may be made by those skilled in the art without departing from the principles and spirit of the invention. The scope of the present invention is defined by the appended claims and equivalents thereof.

Claims (6)

1. The utility model provides a can accurate control fastening torque's bolt-up device, is established ties in proper order by power module, elasticity module and fastening module and constitutes, and the power module includes controller, motor and reduction gear, its characterized in that still includes bolt position real-time detection module, and the controller is according to bolt position adjustment bolt fastening torque and rotational speed size.

2. The bolt-fastening device according to claim 1, wherein the bolt position real-time detection module is a photoelectric encoder.

3. The bolt-fastening device according to claim 1, wherein the elastic module is rubber or a torsion spring.

4. The bolt-fastening device according to claim 1, further comprising a buffer module between the elastic module and the fastening module.

5. The bolt-fastening apparatus of claim 4, wherein the damping module comprises a spring and a coupling.

6. The bolt-fastening device of claim 1, wherein the fastening modules are a batch head adapter and a batch head.

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