SU1558295A3 - Method of tightening a controllable-tightening bolt - Google Patents

Abstract

The invention relates to load-measuring equipment and can be used to control the tightening of threaded connections in the process of tightening them with a wrench. The aim of the invention is to improve the accuracy. The motor of the wrench is started and the controlled screw is first tightened at a predetermined angle Θ, at which the proportionality between the torque and the tightening force is ensured, and the torque F _{F is} measured at this angle. Then, when the screw reaches the angular position Θ + Α, the direction of rotation of the engine is reversed and at the moment of passing the given angle Θ, the unscrewing moment T _{R is} again measured, the magnitude of which calculates the pulling force F _F operating in the screw at a given angle. F _F = ϕ T _F - T _R / P, where P is the thread pitch. Also, the magnitude of the tightening torque T _R corresponding to the given tightening force F T _S = T _F is calculated ^. F _S / F _F. Then, the direction of rotation of the motor of the wrench in the direction of tightening is reversed again and stopped when the torque reaches the value of T _S. 6 Il.

Description

The invention relates to an xylometric technique and can be used to control the tightening torque of threaded connections in the process of tightening them with a wrench.

The aim of the invention is to improve the accuracy.

FIG. 1a and 16 are diagrams and a vector diagram of the forces acting between the screw and the nut; in fig. 2 - tightened threaded connection, longitudinal section; in fig. 3 - dependence of the magnitude of the tightening torque T // and the unscrewing torque Tp on the angular position; in fig. 4 is a plot of torque versus angle of rotation; figure 5 - the structure of the device that implements the proposed method; in fig. 6 - the algorithm of operations implemented by the device shown in Fig „5.

The device for implementing the proposed method contains a wrench 1 and a controller 2. Wrench 1 contains

angle encoder 3, drive motor 4, gearbox 5, torque converter 6, drive shaft 7 and bolt cartridge 8. Controller 2 contains display 9, central processor 10, bullets 11, input interface 12, output interface 13, servo amplifier 14 for driving the engine 4 .

The method is implemented as follows.

, In step No. 1 (Fig. 6), the driving motor 4 of the wrench 1 is started to start pulling. In step No. 2, a check is made of the moment from the output of the converter 6: has the moment value reached the value T0 shown in FIG. 4. If it is reached, then in Step No. 3 the angles of the encoder 3 angles start counting, and in Step No. 4 the equality of the angle of rotation to the given angle 9 is checked. If equality takes place, then in step No. 5 the torque T g is memorized from the torque converter 6 in this angular position.

Then, in step No. 6, the fact of equality of the angle of rotation of the bolt to the second angle of rotation (0 + oi) is determined and, if equality occurs, then in step No. 7 the engine 4 is stopped. The values of 0 and могут 6 can be determined in the range from the lifting point (Fig. 4) to the upper point on the linear inclined part of the curve. T0 value and T.J moment puffs are determined in the initial region and in the middle part of the linear inclined section (Figure 4). In step No. 8, the direction of rotation of the engine 5 is reversed, and in step No. 9, differential turn pulses are delayed until a certain unscrewing moment is reached, indicating sampling of backlash in the bolt cartridge 8 and the dead stroke of the gearbox 5. In step No. 10, the , whether the angle of rotation was reduced to 6, and if it decreased, then in step No. 1 1 the moment T is remembered, unscrewed, and in step No. 12, the engine 4 is stopped. In step No. 13, the numbers 50

force the tightening force Fr, corresponding to the accuracy, the value of the torsional corner 9:

T / are recorded when the controlled screw rotates with a wrench in the direction of tightening when the controlled screw reaches the specified angle 0, and then when the controlled screw reaches the second specified angle (6 + ОО of rotation, greater than the preset angle b of the turn for fixed

T, - T,

F P

where P is the thread pitch, and the magnitude of the moment Te

tightening, corresponding to the specified effort tzhki:

Sat t Ls x ±

0

5 Yu

five

0

35

In this case, the required force FS is installed on the keyboard of the remote control 11 before starting operations to implement the method.

In step 14, engine 4 is restarted in the direction of tightening, and in step 15, the measured tightening torque is equal to TS. If equality takes place, the engine 4 is stopped on the tread number 16.

Claims (1)

Invention Formula Method of tightening a controlled screw connected to a bolt chuck with a given force using a wrench equipped with a motor, a gearbox connected to the engine, an angle encoder connected to a motor connected to the gearbox with a torque converter on which a bolt cartridge is mounted on the drive shaft , and the control controller, which consists in the fact that the controlled screw is first tightened to a given angle 0, at which the proportionality between the torque and the tightening force is ensured, and Fr reattachment operating at the same time in a controlled screw Tf tg R. Fi 0 five where Tg is the tightening torque at a given angular position of the controlled screw; a cool moment of unscrewing at a given angular position of the controlled screw; thread pitch Li T. P 0 and then the controlled screw is pinched to a given pulling force F5, the moment of achievement of which is judged by , I differ, with the aim of increasing the value of g. Fi what. no accuracy, the value of the torque no accuracy, the value of the torque five T / are recorded when the controlled screw rotates with a wrench in the direction of tightening when the controlled screw reaches the specified angle 0, and then when the controlled screw reaches the second specified angle (6 + ОО of rotation, greater than the preset angle b of the turn for fixed Ffiffjs UfCosJS Ufsifffl Phie. 1 $ figa FIG. 2 FIG 4 FIG. 3 F TFig5 Fieb