CN107825427B

CN107825427B - Control method for clamping arm of profile steel sawing machine

Info

Publication number: CN107825427B
Application number: CN201711241101.8A
Authority: CN
Inventors: 叶光平; 汪志远; 张昱; 徐洪; 张利明; 禹良勇; 程良武
Original assignee: Maanshan Iron and Steel Co Ltd
Current assignee: Maanshan Iron and Steel Co Ltd
Priority date: 2017-11-30
Filing date: 2017-11-30
Publication date: 2021-07-09
Anticipated expiration: 2037-11-30
Also published as: CN112809691A; CN112809691B; CN112809692B; CN107825427A; CN112809690B; CN112809692A; CN112809690A

Abstract

The invention discloses a control method of a clamping arm of a section steel sawing machine, which comprises the following functional modules: a clamping arm automatic clamping enabling control unit; a clamping arm automatic clamping speed selection unit; a clamp arm clamping pressure selecting unit; the clamping arm automatically opens the opening control unit; a clamping arm automatic clamping and opening state determination unit; the gripper arm manually operates the control unit. By adopting the technical scheme, aiming at the problem that the position detection encoder of the clamping hydraulic cylinder of the profile steel saw machine clamping arm is difficult to stably work in a severe environment, the control method (or the control program) of the position detection encoder-free position detection encoder of the clamping arm of the profile steel saw machine is provided, and the method controls the opening and clamping positions of the chuck of the clamping arm of the saw machine clamping arm only based on the pressure switch in the clamping hydraulic circuit of the clamping arm, so that the operation reliability of the clamping arm of the profile steel saw machine is greatly improved.

Description

Control method for clamping arm of profile steel sawing machine

Technical Field

The invention belongs to the technical field of metallurgical industrial equipment, and relates to a section steel rolling technology. More particularly, the invention relates to a control method of a clamping arm of a steel saw machine.

Background

A large H-shaped steel saw machine and a clamping arm mechanism thereof in the prior art are shown in figure 1:

the clamping arm mechanism of the large H-shaped steel saw mainly comprises a clamping arm mechanism fixing base 1, a clamping arm lifting frame 2, a clamping arm lifting frame driving hydraulic cylinder 3, a clamping arm chuck 4, a clamping arm clamping rod 5, a clamping arm clamping rod supporting wheel 6, a clamping arm clamping hydraulic cylinder 7 and the like.

The saw clamp arm clamping hydraulic system is shown in fig. 2.

During production, the saw clamp arm lifting frame and the clamp arm carried by the saw clamp arm lifting frame (i.e. the combination of the clamp arm clamp rod 5 and the clamp arm clamp head 4) are in a horizontal position, and the clamp arm clamp rod 5 is in an open state.

After the section steel to be sawed is positioned on the roller way in front of the saw, the clamping arm clamping rod 5 starts the section steel clamping operation under the driving of the clamping arm clamping hydraulic cylinder 7. In this way, the clamp arm clamp 4 will push the section steel to be sawn against the saw-side roll-way side fence 29 at a set pressure;

after the section steel is sawed, the clamping arm chuck 4 is opened to a set position or opened to the maximum position, and waiting for next sawing; the position control of the gripping arm jaws 4 opening and clamping is accomplished by a closed loop position control system consisting of linear encoders mounted inside the gripping arm clamping cylinders and the saw controller.

For the section steel sawing machine, the working environment is quite severe, and in the sawing process of the section steel sawing machine, not only dense water mist exists around the saw blade, but also a large amount of metal powder splashes; in addition, the sawing machine sometimes has severe vibration during the sawing process.

It is for this reason that the position detecting linear encoder of the saw clamp arm clamping cylinder 7 is often problematic.

Disclosure of Invention

The invention provides a control method of a clamping arm of a profile steel sawing machine, and aims to solve the problem that a position detection encoder for a clamping hydraulic cylinder of the clamping arm of the profile steel sawing machine is difficult to stably work in a severe environment.

In order to achieve the purpose, the invention adopts the technical scheme that:

the invention discloses a control method of a clamping arm of a steel saw machine, which comprises the following functional modules:

1. a clamping arm automatic clamping enabling control unit consisting of functional blocks XJJWBC 01-XJWBC 05, XJJWBC08, XJJWBC09, XJWBC 26 and XJWBC 68;

2. a clamp arm automatic clamping speed selection unit composed of functional blocks XJJWBC 10-XJWBC 16 and functional blocks XJJWBC 22-XJWBC 25;

3. a clamp arm clamping pressure selection unit consisting of functional blocks XJJWBC 17-XJWBC 21 and XJJWBC 28;

4. the clamping arm automatic opening control unit is composed of functional blocks XJJWBCs 29-XJWBC 43 and a functional block XJJWBC 55;

5. a clamp arm automatic clamping and opening state determination unit constituted by functional blocks XJJWBCs 47 to xjwbc 54 and functional blocks xjjjwbcs 56 to XJJWBC 66;

6. and a clamping arm manual operation control unit consisting of functional blocks XJJWBC06, XJJWBC07, XJJWBC26, XJJJWBC 27, XJJWBC44 to XJJWBC46, XJJWBC67 and XJJWBC 68.

The control mode of the automatic clamping enabling control unit of the clamping arm is as follows:

when the clamping arm is at a low position, the clamping arm is already at a micro-opening position or a full-opening position, the speed of the roller table before sawing is zero, and an automatic clamping starting instruction of the clamping arm is sent out, an output end Q of a functional block XJWBC 03 generates a pulse of a state '1', an output end Q of a functional block XJJWBC09 is changed from a state '0' to a state '1', and meanwhile, an output end Q of a functional block XJWBC 68 for controlling the opening/closing of a hydraulic control one-way valve of a hydraulic circuit of the clamping arm in a program is changed from a state '0' to a state '1'; therefore, after the clamping arm automatic clamping starting command is sent, the hydraulic control one-way valve of the clamping arm hydraulic circuit is in a two-way conduction state, namely the clamping arm automatic clamping enable is in a release state.

The control mode of the automatic clamping speed selection unit of the clamping arm is as follows:

when the output end Q of the functional block XJWBC 09 is changed from '0' state to '1' state, and the clamping arm automatic clamping enable is in a release state, the clamping arm will perform a fast automatic clamping operation, the fast automatic clamping speed (i.e. the control voltage of the clamping arm proportional control valve) is set by the output end X1 of the functional block XJWBC 23 (e.g. -10V), and is output to the clamping arm proportional control valve by the output end Q of the functional block XJWBC 25, and at the same time, the time of the clamping arm automatic clamping movement operation is timed through the output end ET of the 'timer' functional block XJWBC 10;

based on the response time of the hydraulic control of the clamping arm is about 0.27 second, and the rapid automatic clamping moving speed is 475 mm/s (the control voltage of the proportional control valve of the corresponding clamping arm is-10V), therefore, under the condition that the clamping arm of the saw has no position detection encoder, the rapid automatic clamping moving distance of the clamping arm can be calculated through the functional blocks XJWBC 10-XJWBC 12;

when the fast clamping movement of the clamping arm reaches the distance value of fast/slow switching of the automatic clamping of the clamping arm, the output end Q of the functional block XJWBC 16 is changed from '0' state to '1' state, so that the control voltage output by the output end Q of the functional block XJWBC 25 to the proportional control valve of the clamping arm is switched from-10V during the fast automatic clamping movement to-4V (large clamping force operation mode of the clamping arm) or-7V (small clamping force operation mode of the clamping arm) during the slow automatic clamping movement;

the distance value of the gripping arm automatic gripping (or opening) fast/slow switching is calculated by the functional blocks XJJWBC14 and XJJWBC 15;

the function block XJWBC 14 inputs X1 and X2 are the gripping arm maximum gripping (or opening) movement distance input value (1450 mm) and the section steel width input value (which is set on the HMI operation screen), respectively;

function block xjwbc 15 inputs X2 a slow automatic clamp (or open) movement distance input value (e.g., 150 mm) for the gripper arms; when the distance value of the automatic clamping (or opening) movement of the clamping arm from the full opening (or clamping) position reaches the distance value given by the output end Y of the functional block XJWBC 15 (namely the distance value of the automatic clamping (or opening) fast/slow switching of the clamping arm), the automatic clamping (or opening) speed of the clamping arm is switched from fast speed to slow speed;

when the steel section is clamped by the clamping arm, the input ends I of the functional blocks XJWBC 24 and XJWBC 25 are changed from '0' state to '1' state and from '1' state to '0' state respectively, so that the control voltage output by the output end Q of the functional block XJWBC 25 to the clamping arm proportional control valve is the set value (such as-1.25V) of the input end X2 of the functional block XJWBC 24, and the set value is small and only used for maintaining the pressure after the clamping arm is clamped.

When the clamping arm is not in the automatic clamping enabling state, the input terminals I of the functional blocks XJJWBC24 and XJJWBC25 are both in '0' state, so that the control voltage output by the output terminal Q of the functional block XJJWBC25 is 0V, namely the control voltage of the proportional control valve of the clamping arm output by the automatic clamping speed selecting unit of the clamping arm is 0V.

The control mode of the clamping arm clamping pressure selection unit is as follows:

when the clamping arm of the saw selects a high clamping force operation mode, the output end Q of the functional block XJJWBC20 in the clamping pressure selection unit of the clamping arm is always in a '0' state, the output value of the output end Y of the functional block XJWBC 21 (namely the proportional pressure reducing valve control voltage of the hydraulic circuit of the clamping arm) is equal to the set value 6V (namely the high clamping force set value of the clamping arm) of the input end X1, and therefore the clamping arm of the saw clamps the section steel with high clamping force until the saw reaches the final cutting position;

when the saw clamping arm selects the small clamping force operation mode and the clamping arm moves fast and automatically to reach the distance value of the clamping arm automatic clamping fast/slow switching, or when the saw clamping arm selects the small clamping force operation mode and the clamping arm is already in the micro-opening position, the output end Q of the functional block XJWBC 19 in the clamping arm clamping pressure selection unit will be changed from '0' state to '1' state, and the output end Q of the functional block XJWBC 20 will also be changed from '0' state to '1' state, so that the output value of the output end Y of the functional block XJWBC 21 is equal to the set value 2V of the input end X2 thereof (i.e. the clamping arm small clamping force set value), and the clamping operation of the profile steel will be performed with small clamping force until the saw reaches the final cutting position.

The working mode of the automatic opening control unit of the clamping arm is as follows:

when the saw cuts to the final position, the output end Q of the functional block XJWBC 30 will change from '0' state to '1' state, and at the same time, the output end Q of the functional block XJWBC 68 in the clamping arm automatic clamping enabling control unit will change from '0' state to '1' state, thereby enabling the clamping arm automatic clamping enabling to be in the releasing state;

when the sawing mode of the sawing machine is not the 'last section sawing mode of the section steel rolled piece', the output end Q of the functional block XJJWBC31 is in a '0' state, so that the value of the output end Y of the functional block XJWBC 40 output to the input end X1 of the 'adder' functional block XJWBC 41 is equal to the set value 0V of the input end X1;

when the saw cuts to the final position and the saw cutting mode is not the section steel rolled piece last section cutting mode, the output end Q of the functional block XJWBC 33 is changed from '0' state to '1' state, the output end Q of the functional block XJWBC 34 outputs a pulse of '1' state with the width of 0.9 second, and therefore the input end X2 of the 'adder' functional block XJWBC 41 obtains 6.7V control voltage with the duration of 0.9 second;

since the value of the input terminal X1 of the "adder" function block xjwbc 41 is equal to 0V, the output terminal Y of the "adder" function block xjwbc 41 outputs a control voltage of 6.7V for 0.9 sec to the proportional control valve of the clamp arm, so that the clamp arm is continuously opened for 0.9 sec at an opening speed corresponding to 6.7V from the clamping state, and thus the clamp arm is in a slight-open state (or slight-open position), and after 1.2 sec of the slight-open operation of the clamp arm, the automatic opening control unit of the clamp arm outputs a pulse signal of "slight-open clamp arm-in-place" with a program cycle length through the QN terminal of the function block xjwbc 43;

when the saw cuts to the final position and the saw cutting mode is the 'section steel rolled piece last section saw cutting mode', in order to prevent the next section steel rolled piece to be sawed from striking the saw clamping arm when entering the pre-sawing roller way, the saw clamping arm will be opened rapidly (e.g. 209 mm/s, the control voltage of the corresponding clamping arm proportional control valve is 6.7V):

when the distance of the opening movement of the clamping arm reaches the distance value of the automatic opening fast/slow switching of the clamping arm, the clamping arm is switched from the fast speed to the slow speed (namely the control voltage of the corresponding clamping arm proportional control valve is switched from the fast 6.7V to the slow speed, namely the lower voltage value is 4V) until the clamping arm reaches the maximum opening position;

after the clamping arm of the sawing machine reaches the maximum opening position, allowing the next section steel to be sawn to enter a front sawing roller way for sawing and positioning;

thus, to control the fully open operation of the saw gripper arm without a position detection encoder, the present unit obtains the travel distance during the automatic quick opening operation of the gripper arm through functional blocks XJJWBC36 and XJJWBC 37;

when the distance of the fast opening movement of the gripper arm is less than the distance value given by the output terminal Y of the function block XJJWBC15 in the gripper arm automatic clamping speed selection unit (i.e., the distance value of the gripper arm automatic clamping (or opening) fast/slow switching), the output terminal QL of the function block XJJWBC38 will be in the '1' state;

when the saw cuts to the final position and the saw cutting mode is the section steel rolled piece last section cutting mode, the output end Q of the functional block XJWBC 31 is changed from the state of '0' to the state of '1' until the clamping arm is in the full opening position, so that the control voltage output by the output end Y of the 'adder' functional block XJWBC 41 to the proportional control valve of the clamping arm is equal to the value of the input end X2 of the functional block XJWBC 39 and is equal to 6.7V, and the clamping arm performs the quick opening operation;

when the distance of the fast opening movement of the clamping arm is larger than or equal to the distance value given by the output end Y of the functional block XJJWBC15 in the clamping arm automatic clamping speed selection unit (i.e. the distance value of the fast/slow switching of the clamping arm automatic clamping (or opening), the output end QL of the functional block XJJWBC38 in the unit will change from '1' state to '0' state, because when the saw is saw-cut to the final position and the saw-cut mode is the "section steel rolled piece last section saw-cut mode", the output end Q of the functional block XJJWBC31 will change from '0' state to '1' state until the clamping arm is in the full-open position, so that the control voltage output by the output end Y of the "wbc 41 of the adder" functional block XJJWBC41 to the clamping arm proportional control valve will be equal to the value of the input end X1 of the functional block XJJWBC39 and the clamping arm will perform the slow opening operation.

The control mode of the automatic clamping and opening state judging unit of the clamping arm is as follows:

functional blocks XJJWBC 47-XJWBC 54 in the unit form a clamping arm fully-opened state judgment subunit; the functional blocks XJWBC 56-XJWBC 66 constitute clamping arm clamped state determination subunits;

for the clamping arm fully opened state judgment subunit:

when a pressure switch PS2 (called a pressure switch PS2 for short) installed at the rodless cavity pipeline interface of the hydraulic cylinder of the clamping arm is changed from pressure detection to pressure detection in the opening operation process of the clamping arm, the output end QN of the unit functional block XJJWBC49 generates 1 'pulse of one cycle period, and after 1.5 seconds, the output end Q of the functional block XJWBC 51 outputs 1' pulse lasting for 0.5 seconds;

if the pressure switch PS2 is still in the pressure loss state after 1.5 seconds of pressure loss and the saw has no fault (e.g. the saw has no emergency stop and hydraulic system fault, etc.), the output Q of the "RS flip-flop" function block xjwbc 54 is set to '1', so that the clamping arm fully-opened state determination subunit determines that the clamping arm is in the fully-opened state and sends out the state information that the clamping arm is fully opened;

a clamped state determination subunit for the clamp arm:

when a pressure switch PS1 (called a pressure switch PS1 for short) installed at the pipeline interface of a rod cavity of the hydraulic cylinder of the clamping arm is changed from pressure detection to pressure detection in the process of clamping operation of the clamping arm, the output end QN of the unit functional block XJJWBC56 generates 1 'pulse of one cycle period, and after 1.5 seconds, the output end Q of the functional block XJWBC 58 outputs 1' pulse lasting for 0.5 seconds;

if the pressure switch PS1 is still in the pressure detection state after 1.5 seconds of the pressure detection, and at the same time, the pressure switch PS2 is in the pressure detection state, and the saw is not malfunctioning, the output Q of the "RS flip-flop" function block xjwbc 61 is set to '1', whereby the gripping arm gripped state determination subunit determines that the gripping arm is in the gripping state, and issues the gripping arm gripped state information;

during the clamping operation of the gripper arm, when the distance of the quick opening movement of the gripper arm is greater than the distance value of the automatic clamping quick/slow switching of the gripper arm and the gripper arm is still not in the clamping state after 2.5 seconds, the gripper arm automatic clamping and opening state determination unit outputs a "gripper arm no steel clamping operation" fault message through the output terminal Q of the function block xjwbc 66.

The control mode of the clamping arm manual operation control unit is as follows:

when the operation mode of the saw clamping arm is a manual mode, the saw has no fault (such as no tight stop of the saw, no fault of a hydraulic system and the like), and a clamping arm manual clamping command is given, the output end Q of the functional block XJWBC 07 in the unit is changed from '0' state to '1' state, and the output ends Q of the functional block XJJWBC26 and the functional block XJWBC 68 are also changed from '0' state to '1' state, so that the clamping arm is in an enabling state (namely the clamping arm hydraulic circuit hydraulic control one-way valve is in a two-way conduction state); at the same time, the functional block xjwbc 27 outputs the control voltage value (e.g., -6V) set at its input terminal X2 to the "adder" functional block xjwbc 67, so that the clamp arm will perform the clamping operation at the clamping moving speed corresponding to-6V;

under the normal manual clamping operation state of the clamping arm, the clamping operation of the clamping arm is controlled by a manual clamping instruction of the clamping arm;

when the operation mode of the clamping arm of the saw is a manual mode, the saw has no fault (such as no tight stop of the saw, no fault of a hydraulic system and the like), and a clamping arm manual opening command is given, the output end Q of the functional block XJJWBC45 in the unit is changed from a '0' state to a '1' state, the output end Q of the functional block XJJWBC68 is also changed from a '0' state to a '1' state, and therefore the clamping arm is in an enabling state; at the same time, the functional block xjwbc 46 outputs the control voltage value (e.g., 6V) set at its input terminal X2 to the "adder" functional block xjwbc 67, so that the clamp arm will perform the opening operation at the opening movement speed corresponding to 6V;

in a normal manual opening operation state of the clamp arm, the opening operation of the clamp arm is controlled by a clamp arm manual opening command.

By adopting the technical scheme, the invention provides a control method (or a control program) of a position detection encoder-free device of the clamping arm of the profile steel saw aiming at the problem that the position detection encoder of the clamping hydraulic cylinder of the clamping arm of the profile steel saw is difficult to stably work in a severe environment.

Drawings

The contents of the drawings and the reference numbers in the drawings are briefly described as follows:

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic diagram of the hydraulic drive system of the present invention;

FIG. 3 is a control program structure diagram of the gripping arm of the steel saw machine according to the present invention;

FIG. 4 is an enlarged schematic view of the upper left portion of FIG. 3;

FIG. 5 is an enlarged schematic view of the upper right portion of FIG. 3;

FIG. 6 is an enlarged schematic view of the middle left portion of FIG. 3;

FIG. 7 is an enlarged schematic view of the middle right portion of FIG. 3;

FIG. 8 is an enlarged schematic view of the lower left portion of FIG. 3;

fig. 9 is an enlarged schematic view of the lower right portion of fig. 3.

Labeled as:

1. the device comprises a fixed base, 2, a clamping arm lifting frame, 3, a clamping arm lifting frame driving hydraulic cylinder, 4, a clamping arm chuck, 5, a clamping arm clamping rod, 6, a clamping rod supporting wheel, 7, a clamping arm clamping hydraulic cylinder, 8, a clamping arm clamping hydraulic cylinder fixed support, 9, a bevel gear box, 10, a saw blade, 11, a saw blade cover, 12, a saw blade cover opening and closing hydraulic cylinder, 13, a motor, 14, an upper sliding seat, 15, a balance weight plate, 16, a lubricating pump and a valve group, 17, a thin oil tank, 18, a guide rail, 19, a tail end bearing wheel, 20, H-shaped steel, a rolled piece, 21, a tilting table with a roller way, 22, a hydraulic cylinder, 23, a first pressure switch, 24, a reversing valve, 25, a pressure reducing valve, 26, a proportional control valve, 27, a hydraulic control one-way valve, 28, a second pressure switch, 29 and a side baffle of.

Detailed Description

The following detailed description of the embodiments of the present invention will be given in order to provide those skilled in the art with a more complete, accurate and thorough understanding of the inventive concept and technical solutions of the present invention.

The structure of the present invention as shown in fig. 1 and 2 is a type steel saw.

The invention provides a control method (or a control program) of a position detection-free encoder of a clamping arm of a section steel saw, aiming at the problem that the position detection encoder of the clamping hydraulic cylinder of the clamping arm of the section steel saw is difficult to stably work in a severe environment.

The method controls the opening and clamping positions of the chuck of the clamping arm of the saw machine only based on the pressure switch in the clamping hydraulic circuit of the clamping arm, so that the operation reliability of the clamping arm of the profile steel saw machine is greatly improved.

According to the sawing process of the section steel sawing machine, for a section steel needing to be sawed for multiple times, after the section steel is positioned on a front sawing roller way for the first time, the clamping arm chuck moves from the maximum opening position to the clamping direction of the section steel quickly.

Sawing for the first time:

when the steel to be sawn (the H-shaped steel rolled piece 20) moves to a distance from the saw side roller way side baffle 29, which is smaller than the sum of the width of the steel to be sawn and 150mm, the clamping arm chuck 4 is switched from the fast speed to the slow speed, finally, the steel to be sawn presses against the saw side roller way side baffle 29 at a set pressure, and then the saw starts to saw;

for the second sawing (not the last sawing) of the section steel to be sawn:

after the first sawing of the section steel to be sawn is finished, the clamping arm chuck 4 is quickly opened by a smaller distance (called clamping arm chuck slightly opened for short) from a clamping state; secondly, performing secondary sawing positioning on the section steel by a sawing front roller way;

after the positioning is finished, the clamping arm chuck 4 quickly moves towards the clamping direction of the section steel, finally the section steel to be sawn presses the side roller way side baffle 29 of the sawing machine at a set pressure, and then the sawing machine starts to saw;

after the last sawing is finished:

after the last time of the section steel to be sawn is sawed, the clamping arm chuck 4 is quickly opened from a clamping state, when the section steel moves to a position which is less than 150mm away from the maximum opening position, the clamping arm chuck 4 is quickly switched to a slow speed until the maximum opening position is reached (the clamping arm chuck is fully opened for short), and the section steel is sawed at present.

According to the working state of the clamping arm chuck 4 of the sawing machine in the steel sawing process, the position encoder of the clamping arm clamping hydraulic cylinder adopted in the prior art is only used for detecting the clamping or opening fast and slow switching points of the clamping arm chuck 4 and detecting the slightly opened distance of the clamping arm chuck 4.

In view of the fact that the fast and slow switching points of the clamping or opening of the clamping arm clamps 4 and the slightly opened intervals of the clamping arm clamps 4 can be indirectly obtained through the set fast moving speed of the clamping arm clamps 4 and the required moving time, the invention provides a control program (or a control method) of a position detection-free encoder of the clamping arm of the steel saw, and the structure of the control program is shown in fig. 3 to 9.

In fig. 3 to 9:

NSW is a digital conversion switch function block; when I ═ 1', Y ═ X2; when I ═ 0' state, Y ═ X1.

NCM is a 'numerical comparison' function block; QU is in the '1' state when X1 > X2; when X1 ═ X2, QE is the '1' state; when X1 < X2, QL is the '1' state.

RSR is an RS trigger function block with a preferential reset end R; when S is in a '1' state and R is in a '0' state, Q is in a '1' state and QN is in a '0' state; when S is in a '1' state and R is in a '1' state, Q is in a '0' state and QN is in a '1' state; when S is in '0' state and R is in '0' state, Q and QN are kept in the original state; when S is '0' state and R is '1' state, Q is '0' state and QN is '1' state.

TON is a 'timer' function block; when the input end I is changed from a '0' state to a '1' state, the timing time output end ET starts to time from zero; when the time for which the input end I is changed from the '0' state to the '1' state is longer than or equal to the T end set time, the output end Q is changed from the '0' state to the '1' state, and the timing time output end ET is equal to the T end set time; when the input end I is changed from the '1' state to the '0' state, the output end Q and the timing time output end ET are respectively reset to the '0' state and zero;

ETE is a function block of 'front and back edge identification'; when the input terminal I changes from '0' state to '1' state, the QP terminal only outputs a positive pulse with the length of 1 cycle period, and the QP terminal keeps '0' state in the rest states. When the input end I is changed from a '1' state to a '0' state, the QN end only outputs a positive pulse with the length of 1 cycle period, and the QN end is kept in the '0' state under the other states;

MFP is the "fixed width pulse generator" function block; when the input end I is changed from a '0' state to a '1' state, the Q end outputs 1 positive pulse with the time length of T, and during the period that the Q end outputs the positive pulse, the state change of the input end I does not affect the output state of the Q end;

PCL is a 'pulse generator with limited maximum pulse width' functional block; when the input end I is changed from a '0' state to a '1' state and the duration is greater than or equal to the set time of the T end, the Q end outputs 1 positive pulse with the time length of T; when the input end I changes from the '0' state to the '1' state and the duration is less than the set time of the T end, the Q end outputs 1 positive pulse with the duration equal to the duration of the input end I changing from the '0' state to the '1' state;

ADD is an adder function block;

SUB is a subtracter functional block;

MUL is a 'multiplier' functional block;

PDE is a 'leading edge delay' functional block;

OR is OR gate;

AND is AND gate;

NOT is "NOT gate".

The design and control idea of the control program of the non-position detection encoder of the clamping arm of the steel saw machine is as follows:

the control program of the encoder for detecting the position of the clamping arm of the steel saw machine mainly comprises six control units:

1. the clamping arm automatic clamping enables the control unit:

the control unit consists of functional blocks XJJWBC 01-XJJWBC 05, XJJWBC08, XJJWBC09, XJWBC 26 and XJWBC 68;

2. the clamping arm automatic clamping speed selection unit:

the selection unit is composed of functional blocks XJJWBC 10-XJWBC 16 and functional blocks XJJWBC 22-XJWBC 25;

3. a clamp arm clamping pressure selecting unit:

the selection unit is composed of functional blocks XJJWBC 17-XJWBC 21 and XJJWBC 28;

4. the automatic opening control unit of the clamping arm:

the control unit is composed of functional blocks XJJWBC 29-XJWBC 43 and functional block XJJWBC 55;

5. a grip arm automatic clamping and opening state determination unit:

the determination unit is composed of functional blocks XJJWBC 47-XJWBC 54 and functional blocks XJJWBC 56-XJWBC 66;

6. the clamping arm manual operation control unit:

the control unit is composed of functional blocks XJJWBC06, XJJWBC07, XJJWBC26, XJJWBC27, XJJWBC44 to XJWBC 46, XJWBC 67, and XJWBC 68.

Second, the automatic clamping and enabling control unit of the clamping arm

As can be seen from the fig. 2 saw clamp arm clamping hydraulic system diagram: the clamping and opening operation of the clamping arm can be realized only under the condition that the hydraulic control one-way valve of the hydraulic circuit of the clamping arm is in two-way conduction and the proportional control valve has control voltage.

Since the bidirectional communication of the clamp arm hydraulic circuit pilot operated check valve is a prerequisite for the clamp arm clamping and opening operation, the control of the bidirectional communication of the clamp arm hydraulic circuit pilot operated check valve is referred to as clamp arm enable control.

Thus, the control program of the encoder for detecting the position of the gripping arm of the steel saw machine is provided with a gripping arm automatic clamping enabling control unit for the automatic clamping operation of the gripping arm.

Thirdly, a clamping arm automatic clamping speed selecting unit:

when the fast clamping movement of the clamping arm reaches the distance value of the fast/slow switching of the automatic clamping of the clamping arm, the output end Q of the functional block XJWBC 16 is changed from '0' state to '1' state, so that the control voltage output by the output end Q of the functional block XJWBC 25 to the proportional control valve of the clamping arm is switched from-10V during the fast automatic clamping movement to-4V (large clamping force operation mode of the clamping arm) or-7V (small clamping force operation mode of the clamping arm) during the slow automatic clamping movement.

function block xjwbc 15 inputs X2 a slow automatic clamp (or open) movement distance input value (e.g., 150 mm) for the gripper arms; when the distance value of the clamping arm moving from the full open (or clamping) position for automatic clamping (or opening) reaches the distance value given by the output end Y of the functional block XJJWBC15 (i.e. the distance value of the clamping arm for automatic clamping (or opening) fast/slow switching), the clamping arm automatic clamping (or opening) speed will switch from fast to slow.

Fourthly, a clamping arm clamping pressure selecting unit:

when small-sized section steel is sawn, in order to prevent the section steel from deforming due to overlarge clamping force of a clamping arm of a sawing machine, the clamping arm of the sawing machine usually adopts a small clamping force operation mode;

when big specification shaped steel saw cuts, because the big its resistance of sawing of shaped steel section is also big, in order to prevent to saw the in-process because of the displacement appears in shaped steel and lead to the shaped steel saw oblique, the saw machine centre gripping arm adopts big clamp force operation mode usually.

For this purpose, a clamp arm clamping pressure selection unit is provided in the control program of the encoder for detecting the position of the clamp arm of the steel saw.

When the clamping arm of the saw selects the high clamping force operation mode, the output end Q of the functional block XJJWBC20 in the clamping pressure selection unit of the clamping arm is always in a '0' state, the output value of the output end Y of the functional block XJWBC 21 (namely the proportional pressure reducing valve control voltage of the hydraulic circuit of the clamping arm) is equal to the set value 6V (namely the high clamping force set value of the clamping arm) of the input end X1, and therefore the clamping arm of the saw clamps the section steel with high clamping force until the saw reaches the final cutting position.

When the saw clamping arm selects the small clamping force operation mode and the clamping arm moves fast and automatically to reach the distance value of the clamping arm automatic clamping fast/slow switching, or when the saw clamping arm selects the small clamping force operation mode and the clamping arm is already in the micro-opening position, the output end Q of the functional block XJJWBC19 in the clamping arm clamping pressure selection unit will be changed from '0' state to '1' state, and the output end Q of the functional block XJJWBC20 will also be changed from '0' state to '1' state, so that the output value of the output end Y of the functional block XJWBC 21 is equal to the set value 2V of the input end X2 (namely, the clamping arm small clamping force set value), and the clamping operation of the profile steel will be carried out with small clamping force until the saw reaches the final cutting position.

Fifthly, the automatic opening control unit of the clamping arm:

based on the requirements of the profile steel production process, the sawing machine on part of the profile steel production line needs to saw a section steel rolled piece for multiple times (such as the sawing of the head and the tail of the rolled piece and the sizing), under the condition, in order to shorten the operation time of opening and clamping of the clamping arm of the sawing machine and improve the use efficiency of the sawing machine, the clamping arm of the sawing machine only opens a small gap (slightly opened for short) after the non-last section of the section steel rolled piece is sawed, and after the new sawing and positioning of the section steel rolled piece are finished, the clamping arm clamps the section steel rolled piece at the slightly opened position before sawing.

Therefore, the control program of the encoder for detecting the position of the clamping arm of the section steel saw is provided with a control unit for automatically opening the clamping arm,

when the saw is in the final position and the saw is not in the "last section of rolled section steel" mode, the output Q of the functional block XJJWBC33 will change from '0' state to '1' state, and the output Q of the functional block xjwbc 34 will output a pulse of '1' state with a width of 0.9 seconds, so that the input X2 of the "adder" functional block xjwbc 41 will receive a control voltage of 6.7V for a duration of 0.9 seconds.

Since the value of the input terminal X1 of the "adder" function block xjwbc 41 is equal to 0V, the output terminal Y of the "adder" function block xjwbc 41 outputs a control voltage of 6.7V for 0.9 sec to the proportional control valve of the clamp arm, so that the clamp arm is continuously opened for 0.9 sec at an opening speed corresponding to 6.7V from the clamping state, and thus the clamp arm is in a slightly opened state (or slightly opened position), and after 1.2 sec of the slightly opened operation of the clamp arm, the automatic opening control unit of the clamp arm outputs a pulse signal of "slightly opened clamp arm" for one program cycle length through the QN terminal of the function block xjwbc 43.

and after the clamping arm of the sawing machine reaches the maximum opening position, allowing the next section steel to be sawn to enter a front sawing roller way for sawing and positioning.

Thus, to control the fully open operation of the saw gripper arm without a position detection encoder, the present unit obtains the travel distance during the automatic quick opening operation of the gripper arm through the functional blocks XJJWBC36 and XJJWBC 37.

Sixthly, a clamping arm automatic clamping and opening state judging unit:

the clamping hydraulic system diagram of the clamping arm of the horse steel large H-shaped steel saw shown in figure 2 shows that:

when the clamping arm of the sawing machine is used for clamping, before the clamping arm does not clamp the section steel to be sawn, a pressure switch PS1 (the pressure threshold value of which is about 10 bar) arranged at the pipeline interface of the rod cavity of the hydraulic cylinder driven by the clamping arm is in a pressure detection state; after the clamping arm clamps the section steel to be sawn, the pressure switch PS1 is changed from the pressure detection state to the pressure detection loss state;

similarly, when the clamping arm is opened, before the clamping arm is not fully opened, a pressure switch PS2 (the pressure threshold value of which is about 10 bar) arranged at the pipeline interface of the rodless cavity of the clamping arm driving hydraulic cylinder is in a pressure detection state;

when the clamp arm is fully opened, the pressure switch PS2 changes from the pressure detection state to the pressure loss state.

Therefore, the clamped state and the fully opened state of the clamping arm can be indirectly and accurately judged through the state change of the pressure switch arranged at the interface of the clamping arm driving hydraulic cylinder inlet and outlet pipelines.

Based on this, a clamping arm automatic clamping and opening state judging unit is provided in the section steel saw clamping arm non-position detection encoder control program.

Functional blocks XJJWBC 47-XJWBC 54 in the unit form a clamping arm fully-opened state judgment subunit; the function blocks XJJWBC56 to XJJWBC66 constitute a clamp arm clamped state determination subunit.

For the clamping arm fully opened state judgment subunit:

when the pressure switch PS2 (abbreviated as pressure switch PS2) installed at the rodless chamber line interface of the gripper arm hydraulic cylinder changes from pressure detection to pressure detection during the opening operation of the gripper arm, the output QN of the unit function block XJJWBC49 will generate a '1' pulse of one cycle period, and after 1.5 seconds, the output QN of the function block XJJWBC51 will output a '1' pulse lasting for 0.5 seconds.

If the pressure switch PS2 is still in the pressure loss state after 1.5 seconds of pressure loss and the saw has no fault (e.g. no saw is in a tight stop and no hydraulic system is in a fault), the output Q of the "RS flip-flop" function block xjwbc 54 is set to '1', and thus the clamping arm fully-opened state determination subunit determines that the clamping arm is in the fully-opened state and issues the state information that the clamping arm is fully opened.

A clamped state determination subunit for the clamp arm:

when the pressure switch PS1 (abbreviated as pressure switch PS1) installed at the rod chamber line interface of the gripper arm hydraulic cylinder changes from pressure detection to pressure detection during the gripper arm clamping operation, the output QN of the unit function block XJJWBC56 will generate a '1' pulse of one cycle period, and after 1.5 seconds, the output QN of the function block XJJWBC58 will output a '1' pulse lasting for 0.5 seconds.

If the pressure switch PS1 is still in the pressure detection state after 1.5 seconds of the occurrence of the pressure detection while the pressure switch PS2 is in the pressure detection state and the saw is not malfunctioning, the output Q of the "RS flip-flop" function block xjwbc 61 is set to '1', whereby the gripping arm gripped state determination subunit determines that the gripping arm is in the gripping state and issues the gripping arm gripped state information.

Seventhly, the clamping arm manual operation control unit:

when the operation mode of the saw clamping arm is a manual mode, the saw has no fault (such as no tight stop of the saw, no fault of a hydraulic system and the like), and a clamping arm manual clamping command is given, the output end Q of the functional block XJWBC 07 in the unit is changed from '0' state to '1' state, and the output ends Q of the functional block XJJWBC26 and the functional block XJWBC 68 are also changed from '0' state to '1' state, so that the clamping arm is in an enabling state (namely the clamping arm hydraulic circuit hydraulic control one-way valve is in a two-way conduction state); at the same time, the function block xjwbc 27 outputs the control voltage value (e.g., -6V) set at its input terminal X2 to the "adder" function block xjwbc 67, so that the clamp arm will perform the clamping operation at the clamping moving speed corresponding to-6V.

And under the normal manual clamping operation state of the clamping arm, the clamping operation of the clamping arm is controlled by a manual clamping command of the clamping arm.

When the operation mode of the clamping arm of the saw is a manual mode, the saw has no fault (such as no tight stop of the saw, no fault of a hydraulic system and the like), and a clamping arm manual opening command is given, the output end Q of the functional block XJJWBC45 in the unit is changed from a '0' state to a '1' state, the output end Q of the functional block XJJWBC68 is also changed from a '0' state to a '1' state, and therefore the clamping arm is in an enabling state; at the same time, the functional block xjwbc 46 outputs the control voltage value (e.g., 6V) set at its input terminal X2 to the "adder" functional block xjwbc 67, so that the clamp arm will perform the opening operation at the opening moving speed corresponding to 6V.

The control program (or method) of the encoder without position detection of the clamping arm of the section steel saw machine is used in a cold saw control system of No. 1 horse steel large H-shaped steel, and the actual use effect is good. The technical result can create the economic benefit of hundreds of thousands of yuan each year.

The invention has been described above with reference to the accompanying drawings, it is obvious that the invention is not limited to the specific implementation in the above-described manner, and it is within the scope of the invention to apply the inventive concept and solution to other applications without substantial modification.

Claims

1. A control method of a clamping arm of a steel saw machine is characterized by comprising the following steps: the control method comprises the following functional modules:

1) a clamp arm automatic clamping enabling control unit composed of functional blocks XJJWBC 01-XJJWBC 05, XJJWBC08, XJJJWBC 09, XJWBC 26 and XJWBC 68;

2) a clamp arm automatic clamping speed selection unit composed of functional blocks XJJWBC 10-XJWBC 16 and functional blocks XJJWBC 22-XJWBC 25;

3) a clamp arm clamping pressure selection unit composed of functional blocks XJJWBC 17-XJWBC 21 and XJJWBC 28;

4) the clamping arm automatic opening control unit is composed of functional blocks XJJWBC 29-XJWBC 43 and a functional block XJJWBC 55;

5) a clamp arm automatic clamping and opening state determination unit composed of functional blocks XJJWBC 47-XJWBC 54 and functional blocks XJJWBC 56-XJWBC 66;

6) a clamp arm manual operation control unit composed of functional blocks XJJWBC06, XJJWBC07, XJJWBC26, XJJJWBC 27, XJJWBC44 to XJJWBC46, XJJWBC67, and XJJWBC 68;

when the output end Q of the functional block XJWBC 09 is changed from '0' state to '1' state, and the automatic clamping enable of the clamping arm is in a release state, the clamping arm performs a quick automatic clamping operation, the quick automatic clamping speed is set by the output end X1 of the functional block XJWBC 23 and is output to the clamping arm proportional control valve by the output end Q of the functional block XJWBC 25, and meanwhile, the time of the automatic clamping movement operation of the clamping arm is timed through the output end ET of the 'timer' functional block XJWBC 10;

based on the fact that the response time of the hydraulic control of the clamping arm is 0.27 second and the fast automatic clamping moving speed is 475 mm/s, the fast automatic clamping moving distance of the clamping arm can be calculated through functional blocks XJJWBC 10-XJWBC 12 under the condition that the position detection encoder is not arranged on the clamping arm of the saw;

when the fast clamping movement of the clamping arm reaches the distance value of fast/slow switching of the automatic clamping of the clamping arm, the output end Q of the functional block XJWBC 16 is changed from '0' state to '1' state, so that the control voltage output by the output end Q of the functional block XJWBC 25 to the proportional control valve of the clamping arm is switched from-10V during the fast automatic clamping movement to-4V or-7V during the slow automatic clamping movement;

the distance value of the automatic clamping or opening fast/slow switching of the clamping arm is obtained by the calculation of functional blocks XJJWBC14 and XJJWBC 15;

the input ends X1 and X2 of the function block XJWBC 14 are the maximum gripping or opening movement distance input value and the section steel width input value of the gripping arm, respectively;

the input end X2 of the functional block XJWBC 15 is an input value of the slow automatic clamping or opening movement distance of the clamping arm; when the distance value of the automatic clamping or opening movement of the clamping arm from the full opening or clamping position reaches the distance value given by the output end Y of the functional block XJJWBC15, the automatic clamping or opening speed of the clamping arm is switched from the fast speed to the slow speed;

when the clamping arm clamps the section steel, the input ends I of the functional blocks XJWBC 24 and XJWBC 25 are changed from '0' state to '1' state and from '1' state to '0' state respectively, so that the control voltage output by the output end Q of the functional block XJWBC 25 to the clamping arm proportional control valve is the set value of the input end X2 of the functional block XJWBC 24, and the set value is only used for pressure maintenance after the clamping arm clamps;