SU1311885A1 - Apparatus for adaptive control of motion of welding head along joint - Google Patents

Abstract

This invention relates to systems for automatically guiding a welding head along a joint. The device contains a contour control system, a synchronization unit, a joint sensor, a pulse shaper, a first trigger, a rotational drive with a sensor, a coordinate calculation unit. The second trigger introduced into the device, the delay element, the switch, and two power sources allow symmetrical auto-oscillations of the head with the sensor relative to the midline of the junction. Rigid placement of the sensor on the lever, the welding head allows refusing the use of an additional mechanism of oscillation of the sensor. Introducing the position register block into the device reduces the scanning frequency while maintaining tracking accuracy, and inserting the coordinate register block allows you to adjust the frequency and amplitude of the sensor oscillations, simplifies the programming of the device operation, and provides a joint search. 2 hp f-ly, 8 ill. (L 00 00 SP

Description

I

The invention relates to the automation of welding processes, in particular, to systems for automatically guiding a welding head along a joint, and can be used in adaptive welding.

The aim of the invention is to enhance the functionality and increase the reliability of the device.

The goal is achieved by providing a junction search and initial junction movement without programming, as well as providing speed control and amplitude scanning of the probe with a sensor.

Fig. 1 shows a device, a general view J in Fig. 2 - a welding bar with a sensor, side view} in Fig. 3 - a welding head with a joint sensor, a top view in Fig. 4 - a block diagram of the control system in Fig. 3 - structural view The block of the coordinate registers in FIG. 6 is a block diagram of the block of position registers in FIG. 7 is a block diagram of the contour control system: FIG. 8 is the block diagram of the synchronization block.

The device includes a table moving relative to the horizontal axis X along the guides 2 by means of the drive 3, a drive, 4 rotations moving along the guides 5 along the axis Y by means of the drive 6, which move vertically along the Z axis by means of the drive 7, a welding head 8 connected to the 4th Drive, which rotates it relative to the axis of the electrode. The welding head 8 has a lever 9, on the end of which the joint sensor 10 is rigidly fixed, rotating together with the welding head 8 relative to the axis of the electrode. The device also contains a pulse shaper 11 connected by an input to the output of the interface sensor 10, and an output to a trigger input 12, a loop control system 13, to the output of which is connected a synchronization unit 14, a coordinate calculation unit 15, a rotation sensor 16 mounted on a drive 4 rotation, successively connected to the second trigger 17, the delay element 18 and the switch 19, the signal inputs of which are connected to the outputs of the source 20

852

a positive voltage and a negative voltage source 21, a position register block 22 connected by an input to the output of the system 13

contour control, and the output to the input of the coordinate calculation unit 15, with the output of which the input of the block of 23 coordinate registers is connected, the outputs of the latter are connected to the inputs

the system 13 of the contour control and with the second input of the synchronization unit 14, and the control inputs with the inputs of the synchronization unit 14 and the delay element 18, the output of the switch 19

connected to the input of the rotational drive 4, the output of which is connected to the rotational sensor 16 connected to the information input of the position register unit 22, the control inputs of which are connected to the outputs of the first trigger 12, the second trigger 1 7 and the driver 11 pulses. The position register unit 22 contains the X 24 register, the X 25 register connected by information inputs to the output of the feedback sensor of displacement along the X axis (DN) of the loop control system 13, the U 26 register, the Y register 27, similarly connected to the feedback sensor output on the y-axis (d) register qp 28, register tf29, connected to the output of the rotation sensor 16, the element EXCLUSIVE OR 30, the inverter 31, the element

And 32, element And 33. The inputs of the EXCLUSIVE or 30 element are connected to the outputs of trigger 12 and trigger 17, and its output is connected to the input of inverter 31 and to the first inputs of element 32 and element 33, the second inputs of which are connected to the output of shaper 11 pulses. The outputs of the element 32 are associated with the control inputs of the recording of the register X 24, register Y 26

and the register cf. 28. Element | I 33 outputs are similarly connected to the control inputs of the record of register X 25, register Y 27, register Q29. Information outputs of the registers are connected

with the input of the coordinate calculation unit 15.

Block 23 of the coordinate registers contains registers 34-38 of channel X, registers 39-43 of channel U, registers 44-48 of channel B, multiplexers 49 and 50 of the X, multiplexers 51 and 52 of registers Y, multiplexer 53 of registers B, elok 54 subtraction , block 55 subtraction.

3G

serially connected frequency doubler 56 and counter 57, serially connected counter 58 and unit subtraction element 59. The doubler input 56 of the frequency is connected to the output of the delay element 18, the input of the counter 58 is connected to the output of the synchronization unit 14, the information inputs of the registers 34-48 are connected to the output of the coordinate calculation unit 15. The outputs of subtraction unit 54 of subtraction unit 55, multiplexers 48,51,53 are connected to the inputs of synchronization unit 14 and loop control system 13. The inputs of subtraction unit 54 are connected to the output of multiplexer 49 and to the output of multiplexer 50, the inputs of which are connected to the information outputs of registers 34-38. The inputs of subtractor 55 are connected to the output of multiplexer 51 and. to the output of multiplexer 52, the inputs of which are connected to the outputs of registers 39-43. The inputs of multiplexer 53 are connected to the outputs of registers 44-48. The write control inputs of registers 34-48 are connected to the output of counter 57. The control inputs of multiplexers 49,51,53 are connected to the output of counter 58, and the control inputs of multiplexers 50,52 are connected to the output of subtracting element 59.

The contour control system 13 consists of interpolators 60 and 61 connected to the follower wires control unit 62, feedback sensors 64 and 65, the outputs of which are connected to the input of the synchronization unit 14, the speed driver 66, the output of which is connected to the control ports ) I will give the interpolators 60 and 61. The information inputs of the interpolators 60 and 61 and the speed generator 66 are associated with the outputs of the block 23 of the coordinate registers. Speed generator 66 comprises a series-connected adder 67, a multiplier 68, an adder 69, and an interpolator control block 70.

The synchronization unit 14 consists of a comparator X 71, comparator U 72, the outputs of which are connected to the inputs of the element And 73, the output connected via the one-vibrator 74 with the read control input of the block 23 of the coordinate registers. The inputs of the comparators are connected to the outputs of the system 13 con54

control unit and block 23 coordinate registers.

The shaper 11 pulses are made in the form of a successively connected differentiation unit and a single-oscillator. Triggers 12 and 17 are countable. The coordinate calculation unit 15 is made using a microprocessor. Counter 57 - ring,

counter 58 is binary.

The device works as follows.

Before turning on the device, write down the coordinates of the starting point.

Welding XD, PP and nominal width In cutting the joint of the product to be welded into registers 34, 39, 44. A predetermined width BO is also set in the set, and fed to the adder 67 of the speed controller 66 of the loop control system 13. In the unit contour speed (welding speed) set the desired value of the nominal welding speed V and enter it into the adder 69 of the speed generator 66. Next, have the welding head 8 with the sensor 10 of the joint in the direction of the joint at the starting point with zero coordinates, then turn on the device. From the trigger 17 to the switch 19 comes through the element 18 of the delay signal, causing the connection

a positive voltage source 20 to the actuator 4 is twisted, which causes the joint sensor 10 to rotate with the lever 9 and the welding head 8 relative to the axis of the electrode

in one direction. Counters 57 and 58 and the rest of the registers, when turned on, contain zero information, multiplexers 49, 51, 53 connect the outputs of registers 34, 39, 44 respectively to blocks 54 and 55 of the subtraction and to the second input of adder 67. Multiplexers 50 and 52 are connected to the second inputs of blocks 54 and 55 subtraction registers 38, 43, in which zero information is recorded. From the outputs of the blocks 54, 55, information enters the system 13 of the contour control. The welding head 8 starts moving to the starting point of welding with the coordinates XQ Eq (straight) with the welding speed V (,. As the head 8 approaches the starting point X, Y the joint sensor 10 intersects the edges of the junction at the points P ,, Ho, PP, P (left and right

51

When the intersection of the edge, short rectangular pulses, on the leading edge of which i change their state trigger 12. After the intersection of both edges by the interface sensor 1, the trigger 17, which performs the function of the frequency divider by two, changes its state, caused by the delay time set in the delay element 18, is connected by a switch 19 to the drive 4 of the negative source voltage 21, which leads to the reverse of the joint sensor 10. After the intersection sensor converges the right and then left edges, the direction of rotation changes again in the opposite way, the sensor performs oscillatory movements relative to the interface with an amplitude determined by the delay time of the element 18. At the moment of intersection of the edges, the current the coordinates of the head X, Y and the angle of rotation of the head with the sensor, respectively, for the left and right edges of the joint.

The data corresponding to the left edge is written to registers 24, 26,28, and the right edge to registers 25, 26, 29, which is provided by the write circuit containing the EXCLUSIVE OR 30 element, the inverter 31, and the AND 32 and 33 elements. The element 18 in the coordinate calculation unit 15 calculates the coordinates of the midpoint of the junction using the following formulas

X 54-51.

+ E cos

f;,;

 21.1-21 2

Wu; d, + sififfi,

g.

at ,

Y2 Yir + t sintf ;.

where 2- is the length of the lever 9,

B - cutting width. Indices denote:

1- coordinates, corresponding to the left edge,

2- coordinates, corresponding to the right edge.

1 - current coordinates, g - head.

50

0 5

five

five

0

five

The calculated coordinates of the joint at the moments of the reverse of the sensor of the joint 10 are recorded in block 23 of the coordinate registers, dinat in registers 35, 40, 45, then in registers 36, 41, 46, in registers 37, 42, 47, etc. After recording the joint coordinates in the last registers 38, 43, 48, the information is written in the first registers 34, 39, 44 and again in registers 35, 40, 45, after which the recording cycle is repeated. Recording is controlled by an annular counter 57, connected via frequency doubler 56 to the output of delay element 18. Information is read from the block 23 of the coordinate registers is carried out as the specified displacements i X, Y Y are processed according to the output signal of the synchronization block 14 through blocks 54 and 55 of the subtraction, and in absolute form from the outputs of the multiplexers 49, 51, 53. When the welding head leaves to the initial welding point with coordinates X, the synchronization unit 14 changes the state of the counter 58 by one, which causes the outputs of registers 34 and 35 to be connected by means of multiplexers 49 and 50 to the inputs of the subtractor 54, while the information of the register 35 determines the new co The reference X, similarly, the inputs of the register 55 are connected to the outputs of the registers. 39 and 40, and the register information 40 defines a new point Y. The information about the width of the groove through the multiplexer 53 enters the loop control system 13 in absolute form. After the next drives have been tested, the system 13 of the contour control of the information recorded in registers 35, 40, 45 is used to work out the information from subsequent registers 36, 41, 46 of 37, 42, 47, of 38, 43, 48 and then of 34, 39 , 44 and again from 35, 40, 45, repeat the read cycle. By the time the head reaches the point with the XO coordinates, VO information about the junction line fills only part of the registers (the total number of registers is selected with some margin in order to compensate for possible deviations of the recording speeds and the time interval between the recording and reading can be calculated

vary within certain limits (e.g., 20-30%).

After the head goes to the welding point Xj ,, Od, the welding current is switched on by the signal of the synchronization unit and the recorders start testing the recorded points, during which new information is recorded

As the welding head moves, the cutting width is compared with that set in adder 67, the output of which through multiplication factor multiplier 68 is fed to the input of adder 69, correcting the speed reference to interpolator control unit 70. Thus, in the welding process, the speed driver 66 changes the contour speed, taking into account the width of the butt joint, i.e. during the welding process, the movement of the head is adapted to the width and direction of butt splitting.

Introducing a second trigger, a delay element, a switch and two power sources into the device allows symmetrical self-oscillations of the head by the sensor relative to the midline of the junction, while the amplitude of oscillation is controlled by the delay element, which increases the reliability of the device.

Rigid placement of the sensor on the lever of the welding head makes it possible to refuse to use an additional mechanism for oscillation of the sensor with respect to the tangential direction, eliminating the need for using the system to turn the head in the tangential direction,

Introduction of a position register unit to the device reduces the frequency of scanning while maintaining tracking accuracy, since when the junction edges intersect, the actual coordinates of the welding head are fixed, and the introduction of a block of coordinate registers consisting of separate registers allows non-simultaneous recording and reading, as well as controlling the frequency and amplitude of the sensor oscillations, simplifies the programming of the start of operation of the device, which expands its functionality ..

The device makes it possible to automatically search for a joint and to regulate the amplitude and frequency of the oscillations of the sensor, as well as to increase the reliability of work by reducing the amplitude of the oscillations and simplifying the device.

Claims (2)

1. A device for adaptive control of the movement of the welding head along the junction, containing a contour control system, the output of which is connected to the first input of the synchronization unit, the interface sensor, pulse forwarder and the first trigger, rotation drive with a rotation sensor, coordinate calculation unit, T l and that with the fact that, with the intent of enhancing the functional possibilities and to increase reliability of operation, a second trigger, a delay element, a switch, two power sources, a block of position registers, a block of coordinate registers are additionally introduced, while the inputs of the block of register registers are connected to the outputs of the pulse former, the outputs of the first and second triggers, the output of the rotation sensor and the output of the loop control system, the output of the position register unit through the coordinate calculation unit is connected to the first input of the coordinate register block, the output of which is connected to the second input of the synchronization block and the input of the loop control system, the output of the first trigger through the second trigger connected in series, and the delay ment are connected to the first input of the switch and the second input of the block of coordinate registers, the second input of the block of coordinate registers is connected to the output of the synchronization block, the second and third inputs of the switch zanny with BE moves power supplies, and the output - with. drive input rotation. 2. The device according to claim 1, so that the block of the position registers contains two groups of registers of the cutting position along the X, Y, Cf coordinates, two AND elements, an inverter, an EXCLUSIVE OR element, In this case, the inputs of the EXCLUSIVE element OR are connected to the outputs of the first and second triggers, the output of the last is connected to the first input of the first element I, and through the inverter to the first input of the second element AND, the second inputs elements AND are associated with the output of the pulse former, the outputs of the first and second elements AND are associated respectively with the first inputs of the current position registers in the X, Y coordinates (the first and second groups, the second inputs of the current position registers in the X, Y coordinates are associated with the output contour control system, the second input of the current position register along the coordinate (associated with the rotation sensor output, the outputs of the current position registers X, Y, (associated with the input of the coordinate calculation unit). 3, The device according to claim 1,0, which is so that the block of coordinate registers contains X coordinate registers, Y coordinate registers, butt splitting width registers, two X registers multiplexer, two Y registers multiplexer, registers multiplexer joint width, two counters, two subtractors, unit subtraction unit and doubler frequencies, while the inputs of the coordinate registers X, Y and the width of the groove make up the first input of the block of coordinate registers, the output of the frequency doubler is the second input of this block and its third input is the input of the second counter JI outputs of the first multiplexers of the registers X, Y associated with the first inputs of the subtraction blocks, and the outputs of these blocks constitute the first output of the block of coordinate registers, the second output of the block of coordinate registers, the outputs of all three registers are connected to both corresponding multiplexers, the outputs of the second multiplexer in registers X, U are connected with the second inputs of the subtraction units, the output of the second counter is associated with the control inputs of the multiplexers of the X, Y registers and the width of the joint butt and through the unit of subtraction of the unit connected with the controls of the inputs of the second multiplexers of registers X, Y, the output of the frequency doubler through the first counter is connected to the control inputs of the registers. . five 1 e bJzrti RPI, FIG 2 Fig.Z at. l.lu S. 2J | (/ i, (bi W Cv. Zap. one f UCH ii lo (V3 Win ipopMUp impulse (s) t) 64 61 4X Fig 7 (/ 3) (23) i, yi p.Up. Fig.8 Editor S.Patrusheva Compiled by V. Gribov Tehred A. Kravchuk Order 1921/13 Circulation 976 Subscription VNIIPI USSR State Committee for Inventions and Discoveries 4/5, Moscow, Zh-35, Raushsk nab. 113035 Production and printing company, Uzhgorod, st. Project, 4 Proofreader M. Pojo