Automatic speed regulating system and method for active conveying of a strip blank

Abstract

This invention discloses an automatic speed control system and method for active conveying of strip blanks. The system includes a strip blank conveying frame, a feeding roller device, a detection device, and a control device. The detection device is located upstream of the feeding roller and includes a buffer cylinder, a contact wheel, and a displacement sensor. The contact wheel is mounted on the end of the cylinder piston rod and adheres to the surface of the strip blank under the action of the cylinder. It generates displacement as the tension of the strip blank changes, and the displacement sensor detects this displacement and outputs a signal. The control device adjusts the speed of the feeding roller according to the detection signal. The method is as follows: the piston rod extension and retraction displacement is detected to obtain a tension signal; the signal is compared with a target value to obtain the deviation; a slack or tension is determined; when the deviation exceeds a threshold, a PID closed-loop algorithm is used to generate a speed control command; the speed of the feeding roller is adjusted to make the strip blank tend towards the target state; the above steps are repeated to form a closed loop. This invention detects the tension of the strip blank in real time and automatically adjusts the speed, achieving stable slack control, reducing manual intervention, and improving the degree of automation and production stability.

Description

Technical Field

[0001] This invention relates to the field of water belt production equipment technology, and in particular to an automatic speed regulation system and method for active conveying of belt blanks. Background Technology

[0002] Fire hoses are tubular fabric strips capable of withstanding certain liquid pressures, widely used in building fire protection, industrial conveying, and agricultural irrigation. During the co-extrusion production of fire hoses, the strip blank typically requires active conveying via feed rollers before entering the extrusion die. This reduces the tension exerted on the strip blank by the rear traction device, preventing excessive stress from affecting product quality.

[0003] On existing production lines, the conveying speed of the belt feed rollers is usually set manually based on experience. However, because the strip blank is stretched by the traction device after passing through the die, there is a difference in the elongation of the strip blank before and after the die, resulting in a dynamic relationship between the conveying speeds. In actual production, the tension of the strip blank will continuously fluctuate with changes in factors such as process temperature, material condition, and traction speed.

[0004] If the belt feeding speed is too fast, the output speed of the belt blank from the feeding roller will exceed the corresponding traction speed at the rear end, easily causing the belt blank to be in a slack state, resulting in accumulation, wrinkles, or even abnormal conveying. If the belt feeding speed is too slow, the traction at the rear end will be relatively stronger, easily causing the belt blank to be in a tense state, affecting the dimensional stability and performance of the product. Operators need to frequently observe the tension of the belt blank and continuously fine-tune the belt feeding speed, which is not only labor-intensive but also makes it difficult to ensure adjustment accuracy and production stability.

[0005] The industry currently lacks an automatic speed control solution that can adapt to various specifications of water hose blanks, adapt to changes in tension, and requires no frequent manual intervention. There is an urgent need to develop a simple, easy-to-install, closed-loop automatic speed control device and method for actively conveying and regulating the speed of water hose blanks. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the existing technology, the present invention provides an automatic speed regulation system and method for active conveying of billets, which realizes stable relaxation control in the process of conveying billets, thereby reducing manual adjustment and improving production stability and automation.

[0007] To achieve the above objectives, a first aspect of the present invention provides an automatic speed control system for active conveying of strip billets, comprising a strip conveying frame, a feeding roller device, a detection device, and a control device;

[0008] Both the feeding roller device and the detection device are mounted on the strip conveyor frame, with the detection device located upstream of the feeding roller device along the strip conveying direction.

[0009] The belt feeding roller device includes a belt feeding roller and a strip conveying power unit. The strip conveying power unit is used to drive the belt feeding roller to rotate so as to actively convey the strip.

[0010] The detection device includes a buffer cylinder, a contact wheel, and a displacement sensor, with the contact wheel mounted on the end of the piston rod of the buffer cylinder;

[0011] The contact wheel contacts the surface of the strip under the action of the buffer cylinder, and its displacement changes with the tension of the strip. The displacement sensor is used to detect the displacement change and output a detection signal.

[0012] The control device is electrically connected to both the detection device and the belt feeding roller device, and is used to adjust the conveying speed of the belt feeding roller device according to the detection results of the detection device.

[0013] In some embodiments of the first aspect of this application, the detection device further includes a lateral adjustment slide and a vertical adjustment slide;

[0014] The transverse adjustment slide is used to adjust the position of the contact wheel in the strip width direction;

[0015] The vertical adjustment slide is used to adjust the height position of the contact wheel in the vertical direction.

[0016] In some embodiments of the first aspect of this application, the transverse adjustment slide includes a linear guide, a bidirectional lead screw, and two transverse sliders;

[0017] The bidirectional lead screw has two sections of threads with opposite directions of rotation, which respectively engage with the threads of two transverse sliders to drive the two transverse sliders to move synchronously towards or away from each other.

[0018] One end of the lateral adjustment slide is provided with a lateral adjustment handwheel, which is connected to the bidirectional lead screw drive.

[0019] In some embodiments of the first aspect of this application, two vertical adjustment slides are provided, which are respectively installed on two horizontal sliders of the horizontal adjustment slide;

[0020] Each vertical adjustment slide includes a lead screw, a vertical slider, and a vertical guide rail, and the buffer cylinder is mounted on the vertical slider of the vertical adjustment slide;

[0021] The upper end of the vertical adjustment slide is provided with a vertical adjustment handwheel, which is connected to the lead screw drive.

[0022] In some embodiments of the first aspect of this application, the displacement sensor is mounted on one of the vertical adjustment slides for detecting the extension and retraction displacement of the piston rod of the corresponding buffer cylinder.

[0023] In some embodiments of the first aspect of this application, the detection device is mounted on the strip conveyor frame by a fixed bracket. The fixed bracket has U-shaped clamps at both ends. The U-shaped clamps have a side-opening structure and are equipped with adjusting screws. The adjusting screws are used to press against the crossbeam of the strip conveyor frame to achieve detachable clamping and fixing.

[0024] In some embodiments of the first aspect of this application, the control device includes a controller and a drive control unit;

[0025] The controller uses a PID closed-loop control algorithm based on the detection signal from the displacement sensor to generate speed control commands to adjust the rotational speed of the conveyor roller.

[0026] To achieve the above objectives, a second aspect of the present invention provides an automatic speed control method for active conveying of billets, the speed control method being implemented based on the aforementioned speed control device, comprising:

[0027] S1: The contact wheel contacts the strip blank and generates displacement as the strip blank tension changes. The displacement sensor detects the extension and retraction displacement of the piston rod of the buffer cylinder to obtain the displacement signal corresponding to the tension state of the strip blank.

[0028] S2: Compare the displacement signal with the preset target displacement value and calculate the deviation value;

[0029] S3: Determine whether the strip is in a relaxed or tense state based on the magnitude and sign of the deviation value;

[0030] S4: When the deviation exceeds the preset threshold, a speed adjustment command is generated based on the PID closed-loop control algorithm;

[0031] S5: Adjust the rotational speed of the belt feeding roller according to the speed adjustment command to change the belt blank conveying speed and make the belt blank tension state tend to the target displacement value.

[0032] S6: Repeat steps S1 to S5 to form a closed-loop control.

[0033] In some embodiments of the second aspect of this application, step S3 includes:

[0034] When the deviation value is greater than zero, the strip is determined to be in a relaxed state;

[0035] When the deviation value is less than zero, the strip is determined to be in a tensioned state;

[0036] When the deviation is within the preset error range, the current conveying speed remains unchanged.

[0037] In some embodiments of the second aspect of this application, a device installation and position adjustment step is included before step S1:

[0038] The tool-free clamping and fixing of the bracket to the blank conveyor is achieved by using a U-shaped clamp;

[0039] Operate the lateral adjustment handwheel of the lateral adjustment slide to adjust the lateral distance between the two contact wheels to match the billet diameter;

[0040] Operate the vertical adjustment handwheel of the vertical adjustment slide to adjust the vertical height of the contact wheel to match the laying height of the strip.

[0041] The advantages of this invention are as follows: First, relying on real-time detection by displacement sensors and PID closed-loop automatic speed regulation, the production process eliminates the need for manual periodic inspections and frequent fine-tuning of the conveyor speed, saving dedicated adjustment personnel and significantly reducing the labor intensity of operators. Second, the configuration of horizontal and vertical adjustment slides allows for flexible adjustment of the horizontal position and vertical height of the contact wheel, adapting to different diameters and heights of water conveyor belt blanks. One device can meet the needs of production lines for multiple product models, making it widely applicable. Third, the tool-free clamping and fixing method using U-shaped clips allows for direct and quick installation on existing belt blank conveyor frames, facilitating disassembly, relocation, and upgrading of existing old production lines. Finally, the use of a buffer cylinder ensures that the contact wheel maintains constant pressure against the belt blank, allowing for real-time sensing of belt blank tension changes. Combined with precise PID closed-loop speed regulation, this effectively prevents the belt blank from being stretched and deformed due to excessive tightness or accumulating and wrinkling due to excessive looseness, ensuring continuous and stable production operation. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the detection device described in this invention;

[0044] Figure 2 This is a schematic diagram of the automatic speed control system described in this invention;

[0045] Figure 3 This is a schematic diagram of the working state of the automatic speed control system described in this invention;

[0046] Figure 4 This is a schematic flowchart of an automatic speed control method for active conveying of billets according to the present invention.

[0047] Component identification:

[0048] 1. Fixed bracket; 2. U-shaped clamp; 2a. Adjusting screw; 3. Horizontal adjusting slide; 3a. Linear guide rail; 3b. Two-way lead screw; 3c. Horizontal slider; 3d. Horizontal adjusting handwheel; 4. Vertical adjusting slide; 4a. Vertical adjusting handwheel; 5. Buffer cylinder; 6. Contact wheel; 7. Displacement sensor; 8. Connecting plate; 9. Detection device; 10. Belt feeding roller device; 11. Strip conveying power unit; 12. Strip conveying frame; 13. Belt feeding roller; 14. Strip; 15. Die pull rod pressure roller. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] Example 1:

[0051] like Figures 1 to 3 As shown, the automatic speed control system for active conveying of water-filled belt blanks provided in this embodiment includes a belt blank conveying frame 12, a belt feeding roller device 10, a detection device 9, and a control device.

[0052] The belt feeding roller device is used to actively convey the belt blank; the detection device 9 is used to detect the tension of the belt blank; the control device is electrically connected to the detection device 9 and the belt feeding roller device respectively to realize automatic speed regulation during the belt blank conveying process.

[0053] The belt feeding roller device and the detection device 9 are both installed on the strip conveyor frame 12, and the detection device 9 is located in front of the belt feeding roller device, that is, along the conveying direction of the strip, the detection device 9 is set on the upstream side of the belt feeding roller device.

[0054] The strip conveyor frame 12 is the supporting structure of the strip conveying system. It is equipped with transverse support beams or profile components for installing the strip feeding roller device and the detection device 9. It is used to support and install various functional components in the strip conveying process and to provide a stable structural foundation for the continuous conveying of strips.

[0055] In this embodiment of the invention, the detection device 9 is mounted on the fixed bracket 1 via the connecting plate 8. The fixed bracket 1 is a horizontally arranged support rod used to support the various functional components in the detection assembly.

[0056] Preferably, the fixed bracket 1 is detachably mounted on the blank conveying frame 11 by means of U-shaped clamps 2 provided at both ends of it.

[0057] The U-shaped clamp 2 is a U-shaped clamping structure with an opening on one side, which can be directly inserted into the crossbeam or profile component of the blank conveying frame 11 from the side; the lower end of the U-shaped clamp 2 is provided with an adjusting screw 2a, and by rotating the adjusting screw 2a, its end gradually presses against the lower surface of the crossbeam, thereby pressing and fixing the U-shaped clamp 2 and the crossbeam.

[0058] With the above structure, when it is necessary to install the detection device 9, simply insert the U-shaped clamp 2 into the crossbeam of the blank conveying frame 12 from the side and tighten the adjusting screw 2a to complete the fixation; when it is necessary to disassemble or adjust the installation position of the detection device 9, loosen the adjusting screw 2a to quickly remove or move the device, which is simple to operate and does not require additional tools.

[0059] The detection device 9 includes a buffer cylinder, a contact wheel, and a displacement sensor. The contact wheel is mounted on the end of the piston rod of the buffer cylinder and is used to contact the surface of the strip and float as the tension of the strip changes. The displacement sensor is used to detect the extension and retraction displacement of the piston rod of the buffer cylinder to obtain a signal reflecting the tension of the strip.

[0060] In this embodiment of the invention, to adapt to the testing requirements of strip blanks of different specifications, the testing device 9 is further provided with a transverse adjustment slide and a vertical adjustment slide. The transverse adjustment slide is used to adjust the position of the contact wheel in the width direction of the strip blank to adapt to strip blanks of different widths or diameters; the vertical adjustment slide is used to adjust the height position of the contact wheel in the vertical direction to adapt to strip blanks of different thicknesses or different laying heights.

[0061] In this embodiment of the invention, the transverse adjustment slide 3 includes a linear guide rail 3a, a bidirectional lead screw 3b, and two transverse sliders 3c. The two transverse sliders 3c are respectively mounted on the linear guide rail 3a and threadedly engaged with the bidirectional lead screw.

[0062] A horizontal adjustment handwheel 3d is provided at one end of the horizontal adjustment slide 3. The horizontal adjustment handwheel 3d is connected to the bidirectional lead screw 3b. By rotating the horizontal adjustment handwheel 3d, the bidirectional lead screw 3b is driven to rotate, so that the two horizontal sliders 3c located on both sides of the lead screw move synchronously towards or away from each other on the linear guide rail 3a, thereby realizing the synchronous adjustment of the distance between the two horizontal sliders 3c.

[0063] Specifically, the surface of the bidirectional lead screw 3b is machined with two threaded sections with opposite directions of rotation along the axial direction, namely a left-hand threaded section and a right-hand threaded section. Nuts matching their respective threaded sections are fixed inside the two transverse sliders 3c (or the transverse slider 3c body itself is directly machined with internal threads). The nut inside one transverse slider 3c engages with the left-hand threaded section, and the nut inside the other transverse slider 3c engages with the right-hand threaded section. Both ends of the bidirectional lead screw 3b are supported on the base of the transverse adjusting slide 3 via bearing seats. One end of the lead screw extends and is fixed with a transverse adjusting handwheel 3d. When the transverse adjusting handwheel 3d drives the bidirectional lead screw 3b to rotate, the left-hand threaded section drives its mating nut to move left or right, while the right-hand threaded section simultaneously drives the other nut to move in the opposite direction, thereby causing the two transverse sliders 3c to move synchronously towards or away from each other on the linear guide rail 3a. This connection structure converts rotational motion into symmetrical linear motion of the two transverse sliders 3c, ensuring that the spacing adjustment of the two vertical adjusting slides 4 is synchronous and equidistant.

[0064] There are two vertical adjustment slides 4, which are respectively installed on the two horizontal sliders 3c of the horizontal adjustment slide 3. The vertical adjustment slides 4 adjust their positions synchronously in the horizontal direction as the sliders move.

[0065] In this embodiment of the invention, the vertical adjustment slide 4 includes a lead screw, a vertical slider, and a vertical guide rail (not shown in the figure). The vertical adjustment handwheel 4a is located at the upper end of the vertical adjustment slide 4. The vertical adjustment handwheel 4a is connected to the vertically arranged lead screw. By rotating the vertical adjustment handwheel 4a, the vertical lead screw is driven to rotate, thereby causing the vertical slider in the vertical adjustment slide 4 to move up and down along the vertical guide rail.

[0066] There are two buffer cylinders 5, which are respectively installed on the vertical sliders of the two vertical adjustment slides 4.

[0067] Preferably, the buffer cylinder 5 is a single-acting or double-acting cylinder, and compressed air of a certain pressure is introduced through the air source system, so that the piston rod of the buffer cylinder 5 can freely extend or retract according to the tightness of the strip 14, thereby making the contact wheel 6 always in close contact with the surface of the strip 14 with a constant pressure.

[0068] Preferably, the contact wheel 6 is made of wear-resistant nylon or polyurethane. It is always in close contact with the surface of the strip 14 by the constant pressure of the buffer cylinder 5, and can rotate flexibly as the strip moves horizontally, which ensures the reliability of the detection and avoids damage to the strip.

[0069] During operation, the contact wheel 6 rolls in contact with the surface of the strip 14 and can roll in the conveying direction of the strip 14; at the same time, the buffer cylinder 5 can automatically extend and retract within its stroke range according to the pressure change caused by the change in the tightness of the strip 14, thereby converting the tension change of the strip 14 into the displacement change of the buffer cylinder 5.

[0070] In this way, the horizontal spacing of the two sets of vertical adjustment slides 4, buffer cylinders 5 and contact wheels 6 can be adjusted simultaneously by the horizontal adjustment slide 3 to adapt to different diameter specifications of water hose blanks 14; the vertical height of the buffer cylinders 5 and contact wheels 6 can be adjusted simultaneously by the vertical adjustment slide 4 to adapt to different thicknesses, different laying heights and different tensions of the hose blanks, so that the contact wheels 6 can accurately and stably press against the opposite two sides of the hose blank 14 and form a stable contact with the hose blank 14, providing a reliable detection basis for the subsequent automatic speed adjustment of the hose blank.

[0071] In this embodiment of the invention, a displacement sensor 7 is installed on one of the vertical adjustment slides 4. The displacement sensor 7 is used to detect the extension and retraction displacement of the buffer cylinder 5.

[0072] Specifically, the fixed end of the displacement sensor 7 is installed on the support structure of the vertical adjustment slide 4, and its detection end is correspondingly set with the piston rod of the buffer cylinder 5 or the connecting part that moves synchronously with the piston rod, so that the displacement sensor 7 can collect the displacement changes of the buffer cylinder 5 in the vertical direction in real time.

[0073] During operation, when the tension of the strip 14 changes, the contact wheel 6 moves up and down, thereby driving the piston rod of the buffer cylinder 5 to extend and retract. The displacement sensor 7 detects the displacement change synchronously and outputs the detection signal to the control device in the form of an electrical signal.

[0074] Preferably, the displacement sensor 7 is a linear displacement sensor, and its detection direction is consistent with the extension and retraction direction of the buffer cylinder 5, so as to improve detection accuracy and signal stability.

[0075] The belt feeding roller device 10 includes a belt feeding roller 13 and a belt blank conveying power unit 11 disposed on the belt blank conveying frame 12, which is used to provide active conveying power to the belt blank and drive the belt blank to move along the conveying direction.

[0076] The conveying roller 13 is arranged along the conveying direction of the strip blank 14, and its axis is basically perpendicular to the running direction of the strip blank 14. It is mounted on the strip blank conveying frame 12 through bearings so that it can rotate smoothly around its own axis.

[0077] Preferably, the outer surface of the conveyor roller 13 is a wear-resistant and anti-slip structure to enhance the friction between it and the strip blank 14, thereby effectively driving the strip blank 14 forward during rotation.

[0078] The belt feeding rollers 13 are arranged in two symmetrical rows, and the belt blank 14 is located between the two rows of belt feeding rollers 13. This allows the upper and lower rollers to clamp the belt blank 14 from both sides and drive it forward, effectively preventing slippage and significantly improving the stability and reliability of the conveying.

[0079] The strip 14 passes between the feed roller 13 and the die tie rod pressure roller 15. The feed roller 13 is driven to convey the strip 14 forward. The die tie rod pressure roller 15 cooperates with the feed roller 13 to form a clamping channel, ensuring that the strip 14 maintains a stable posture during conveying and preventing the strip 14 from shifting or twisting before entering the extrusion die. The die tie rod pressure roller 15 is mounted on the strip conveyor frame 12, and its position is adjustable to accommodate strips 14 of different specifications.

[0080] Preferably, multiple upper and lower rows of conveying rollers 13 can be provided and arranged at intervals along the conveying direction of the strip blank to improve the stability and continuity of the conveying.

[0081] The strip conveying power unit 11 is connected to the strip feeding roller 13 for driving the strip feeding roller 13 to rotate.

[0082] The strip conveying power unit 11 includes a drive motor and a transmission mechanism, wherein the transmission mechanism can be a coupling, a reducer or a belt drive structure, used to transmit the power of the drive motor to the conveying roller 13, so that it rotates at a set speed, thereby realizing the conveying of the strip 14.

[0083] The control device is electrically connected to the displacement sensor 7 of the detection device 9 and the strip conveying power unit 11 of the strip feeding roller device 10. The control device preferably adopts a programmable logic controller (PLC) or an industrial controller, and adjusts the speed of the strip feeding roller 13 through a frequency converter or servo driver.

[0084] The control device achieves real-time control of the speed of the conveyor roller 13 by adjusting the speed of the drive motor. Specifically, when the control device determines, based on the signal feedback from the displacement sensor 7, that the tension of the strip blank 14 has changed and reached a preset threshold, it changes the speed of the drive motor to increase or decrease the speed of the conveyor roller 13 accordingly, thereby changing the conveying speed of the strip blank 14 and achieving automatic adjustment of the slack state of the strip blank.

[0085] The control device has a built-in control algorithm module, and its working process is as follows: First, it receives the displacement signal of the buffer cylinder 5 detected by the displacement sensor 7 in real time, as a feedback quantity of the looseness of the strip 14; then, it compares the real-time displacement value with the preset target position and calculates the deviation value; finally, it uses a PID closed-loop control algorithm to generate a corresponding speed adjustment signal according to the magnitude and trend of the deviation.

[0086] As can be seen from the above description, the conveying roller device 10, as an execution unit, can dynamically adjust the conveying speed of the strip blank 14 under the regulation of the control device. Together with the detection unit composed of the displacement sensor 7 and the control device, it forms a closed-loop control device, thereby realizing the automatic speed adjustment function of the strip blank 14 during the conveying process.

[0087] As described above, the specific process of adjusting the strip in the automatic speed control system of the present invention is as follows:

[0088] When the strip is too loose, the contact wheel loses sufficient support, and the buffer cylinder extends downwards under constant air pressure. The displacement sensor detects that the cylinder extension length has increased (the detected value exceeds the target value). Based on this, the control device determines that the strip is excessively loose and outputs a deceleration signal through PID control to reduce the speed of the feed rollers and decrease the conveying speed. As the conveying speed of the feed rollers decreases, the traction at the rear end is relatively enhanced, the strip is gradually tightened, the support force on the contact wheel is increased, and the buffer cylinder gradually retracts to the set range, completing the automatic correction.

[0089] When the strip is too tight, it presses upward against the contact wheel, compressing and retracting the buffer cylinder. The displacement sensor detects a decrease in the cylinder's extension length (the detected value is lower than the target value). The control device determines that the strip is over-tensioned and outputs an acceleration signal to increase the speed of the feed rollers. As the feed rollers increase their speed, the strip becomes more relaxed, reducing its tension and the pressure on the contact wheel. Under air pressure, the buffer cylinder extends back to the set range, achieving automatic adjustment.

[0090] Example 2:

[0091] Based on the automatic speed control system described in Embodiment 1, this embodiment provides an automatic speed control method for active conveying of water-loaded blanks. It utilizes the coordinated cooperation between a fixed bracket 1, a U-shaped clamp 2, a horizontal adjusting slide 3, a vertical adjusting slide 4, a buffer cylinder 5, a contact wheel 6, a displacement sensor 7, and a control device to achieve automatic speed control of the blanks.

[0092] Figure 4 The overall flow diagram of this speed regulation method is shown, such as... Figure 4 As shown, the speed regulation method includes the following steps:

[0093] Step S1: Device installation and position adjustment.

[0094] This step is used to quickly install the automatic speed control system onto the conveyor frame for the conveyor belt, and to adjust the lateral spacing and vertical height of the contact wheels according to the specifications and dimensions of the conveyor belt, so that the device is compatible with different types of conveyor belts. Specifically, it includes the following steps:

[0095] Step S11: Installation of the fixed bracket.

[0096] First, insert the U-shaped clamps 2 at both ends of the fixed bracket 1 into the crossbeam of the blank conveying frame 12 from the side, so that the U-shaped opening of the U-shaped clamp 2 locks the crossbeam.

[0097] Then, rotate the adjusting screw 2a at the lower end of the U-shaped clamp 2 so that the end of the adjusting screw 2a gradually presses against the lower surface of the crossbeam, thereby pressing and fixing the U-shaped clamp 2 onto the crossbeam, thus realizing tool-free clamping and fixing of the fixed bracket 1 and the blank conveying frame 12.

[0098] During installation, if it is necessary to disassemble or adjust the installation position, simply rotate the adjusting screw 2a in the opposite direction to loosen the U-shaped clamp 2. The operation is simple and quick.

[0099] Step S12: Adjustment of the lateral spacing of the contact wheels.

[0100] According to the diameter specifications of the water conveyor belt blank 14 to be conveyed, operate the horizontal adjustment handwheel 3d set at one end of the horizontal adjustment slide 3.

[0101] Rotating the horizontal adjustment handwheel 3d drives the bidirectional lead screw 3b to rotate. Since the bidirectional lead screw 3b has two threaded sections with opposite directions of rotation, which mesh with the nuts in the two horizontal sliders 3c respectively, the two horizontal sliders 3c move synchronously towards or away from each other on the linear guide rail 3a.

[0102] By rotating the horizontal adjustment handwheel 3d forward or backward, the distance between the two horizontal sliders 3c can be precisely adjusted, thereby driving the two sets of vertical adjustment slides 4, buffer cylinders 5 and contact wheels 6 installed on the horizontal sliders 3c to move synchronously, so that the horizontal distance between the two contact wheels 6 matches the width of the water belt blank 14.

[0103] After adjustment, the two contact wheels 6 are tightly fitted to the two symmetrical edges of the water belt blank 14.

[0104] Step S13: Adjust the vertical height of the contact wheel.

[0105] Operate the vertical adjustment handwheels 4a located on the upper end of the two vertical adjustment slides 4 respectively. Rotating the vertical adjustment handwheels 4a drives the vertically arranged lead screw to rotate, and the lead screw drives the vertical slider to move up and down along the vertical guide rail. A buffer cylinder 5 is fixedly installed on the vertical slider, and a contact wheel 6 is installed at the end of the piston rod of the buffer cylinder 5.

[0106] By rotating the vertical adjustment handwheel 4a forward or backward, the vertical height of the contact wheel 6 can be precisely adjusted to correspond to the laying height and surface position of the water hose blank 14, ensuring that the contact wheel 6 can contact the surface of the hose blank 14 in an appropriate position.

[0107] During adjustment, the vertical height of the two contact wheels 6 can be adjusted independently according to the working conditions of the strip blank with different thicknesses and tightness, so that the contact wheels 6 and the strip blank 14 can achieve the best fit.

[0108] Step S2: Constant pressure bonding of contact wheels.

[0109] This step involves introducing compressed air at a constant pressure into the buffer cylinder, causing the contact wheel to adhere to the surface of the strip with a constant pressure and roll flexibly with the movement of the strip, thereby sensing changes in the tension of the strip in real time. Specifically, it includes the following steps:

[0110] Step S21: Vent the buffer cylinder.

[0111] Compressed air at a constant pressure is supplied to the buffer cylinder 5 through the air supply system. The buffer cylinder 5 can be a single-acting or double-acting cylinder, depending on the actual working conditions.

[0112] The compressed air pressure value is preset to ensure that the contact wheel 6 can apply sufficient and stable contact pressure to the strip 14, so that the pressure is not too low and the tightness change cannot be effectively detected, nor is the strip deformed due to excessive pressure.

[0113] Step S22: The contact wheel extends and engages.

[0114] Under constant air pressure, the piston rod of the buffer cylinder 5 extends outward, driving the contact wheel 6 installed at the end of the piston rod to move toward the surface of the strip 14 until the contact wheel 6 is tightly pressed against the surface of the strip 14 with constant pressure.

[0115] Because the internal air pressure of the buffer cylinder 5 remains constant, the piston rod can automatically adjust its extension length according to the slight undulations on the surface of the strip 14, thereby ensuring that the contact wheel 6 always maintains stable contact with the strip 14.

[0116] Step S23: Contact wheel rolling sensing.

[0117] When the strip blank 14 is conveyed forward under the drive of the feeding roller 13, the contact wheel 6 forms rolling contact with the surface of the strip blank 14, and the contact wheel 6 rotates flexibly with the conveying direction of the strip blank 14.

[0118] During this process, the contact wheel 6 senses the changes in the tension of the strip 14 in real time: when the strip 14 becomes loose, the supporting force of the strip 14 on the contact wheel 6 weakens, and the piston rod of the buffer cylinder 5 extends further; when the strip 14 becomes tight, the strip 14 presses upward against the contact wheel 6, and the piston rod of the buffer cylinder 5 is compressed and retracts. The up-and-down movement of the contact wheel 6 directly reflects the tension of the strip 14.

[0119] Step S3: Real-time detection of displacement signals.

[0120] This step involves using a displacement sensor to detect the extension and retraction displacement of the buffer cylinder piston rod in real time, and converting the displacement signal into an electrical signal to be sent to the control device. Specifically, it includes the following steps:

[0121] Step S31: Displacement sensor initialization and alignment.

[0122] The displacement sensor 7 is a linear displacement sensor. Its fixed end is installed on the support structure of the vertical adjustment slide 4, and its detection end is set corresponding to the piston rod of the buffer cylinder 5 or the connecting part that moves synchronously with the piston rod.

[0123] During installation, it is necessary to ensure that the detection direction of the displacement sensor 7 is consistent with the extension and retraction direction of the piston rod of the buffer cylinder 5 to ensure detection accuracy and signal stability.

[0124] The range of displacement sensor 7 should cover the maximum extension and retraction range of the piston rod of buffer cylinder 5.

[0125] Step S32: Real-time acquisition of displacement signals.

[0126] When the tension of the strip 14 changes, the contact wheel 6 moves up and down, causing the piston rod of the buffer cylinder 5 to extend and retract.

[0127] At this time, the displacement sensor 7 synchronously detects the displacement change and collects the offset of the piston rod extension length of the buffer cylinder 5 relative to the reference position in real time in the form of analog signals (such as 4-20mA current signals or 0-10V voltage signals).

[0128] The signal acquisition frequency is determined by the scanning cycle of the control device to ensure that the dynamic changes in the tension of the strip can be captured in a timely manner.

[0129] Step S33: Signal transmission and processing.

[0130] The displacement sensor 7 outputs the collected real-time displacement signal in the form of an electrical signal, which is transmitted to the control device through a shielded cable.

[0131] After receiving the signal, the control device performs analog-to-digital conversion and filtering to eliminate noise interference and obtain a stable and reliable real-time displacement value, which serves as feedback on the relaxation degree of the strip 14 for subsequent comparison and calculation.

[0132] Step S4: Generate speed control command.

[0133] This step compares the real-time displacement signal with the preset target displacement value, calculates the deviation value, determines the tension of the strip based on the deviation, and generates corresponding speed adjustment commands through a PID control algorithm. Specifically, it includes the following steps:

[0134] Step S41: Preset target displacement value.

[0135] Based on the ideal relaxation state of the water hose blank 14 during normal conveying, the target displacement value S of the piston rod of the buffer cylinder 5 is preset in the control device. target This target displacement value corresponds to the reference height position of the contact wheel 6 when the strip 14 is in a stable relaxed state.

[0136] The target displacement value can be determined through on-site debugging. Different target values ​​can be set for water hose blanks of different specifications and materials, and saved in the parameter table of the control device for quick recall and switching.

[0137] Step S42: Calculate the deviation value.

[0138] The control device receives the current displacement signal S(t) from the displacement sensor 7 in real time, and compares this real-time displacement value with the preset target displacement value S. target The deviation value e(t) is calculated by comparing the values ​​using the following formula:

[0139] e(t) = S(t) - S target

[0140] in:

[0141] e(t) is the deviation value at time t (unit: mm);

[0142] S(t) is the piston rod extension length detected in real time by the displacement sensor (unit: mm).

[0143] S target The preset target displacement value (unit: mm).

[0144] When e(t) > 0, it indicates that the real-time displacement is greater than the target value, that is, the piston rod of the buffer cylinder 5 extends too far and the strip is too loose; when e(t) < 0, it indicates that the real-time displacement is less than the target value, that is, the piston rod of the buffer cylinder 5 retracts too much and the strip is too tight; when |e(t)| ≤ δ (δ is a preset threshold), the deviation value is within the allowable error range, indicating that the strip is in a normal loose state and there is no need to trigger speed regulation.

[0145] Step S43: Generate speed control command.

[0146] The control device has a built-in PID closed-loop control algorithm module. Based on the calculated deviation value e(t) and its trend, it performs calculations using proportional, integral, and derivative coefficients to generate corresponding speed adjustment commands. The mathematical expression of the PID control law is as follows:

[0147]

[0148] Alternatively, a discretized form of positional PID can be used:

[0149]

[0150] in:

[0151] u(t) or u(k) is the control quantity output by the PID controller (corresponding to the speed regulation signal, unit: Hz or rpm);

[0152] K p For proportional gain;

[0153] T i The integral time constant (in seconds) and the integral coefficient K i = K p / T i ;

[0154] T d The differential time constant (unit: s) and the differential coefficient K d = K p * T d ;

[0155] e(t) is the deviation signal;

[0156] Δt is the sampling period (unit: s);

[0157] k is the sampling sequence number.

[0158] Based on the sign and magnitude of the deviation, the PID controller outputs the corresponding control quantity:

[0159] When e(t) > 0 and |e(t)| > δ (the strip is too loose), the control device generates a deceleration command to reduce the speed of the feeding roller 13, thereby reducing the conveying speed of the strip and gradually restoring the strip to a taut state.

[0160] When e(t) < 0 and |e(t)| > δ (the strip is too tight), the control device generates an acceleration command to increase the rotational speed of the feeding roller 13, thereby increasing the strip conveying speed, reducing the strip tension, and restoring the strip to the target relaxed state.

[0161] Wherein, PID parameter K p T i T d The system needs to be tuned according to its response characteristics and control accuracy requirements (e.g., using the Ziegler-Nichols method or empirical trial and error) to achieve a fast, stable, and overshoot-free speed regulation effect.

[0162] The control device repeatedly performs the above deviation calculation and PID operation in each sampling cycle to form a closed-loop negative feedback control, so that the tension of the strip is always stable near the target value.

[0163] Step S5: Execute speed adjustment.

[0164] This step, based on the speed adjustment command generated by the PID controller, changes the rotational speed of the conveyor rollers through the drive motor and transmission mechanism, thereby achieving dynamic adjustment of the conveyor speed of the strip blank and bringing the tension of the strip blank back to the target range. Specifically, it includes the following steps:

[0165] Step S51: Receive the instruction and convert it into a drive signal.

[0166] The control device receives the speed adjustment command output by the PID controller in step S43 (i.e., the command generated based on the control quantity u(t) or u(k) output by the PID controller). This command is sent to the frequency converter or servo drive in the form of an electrical signal.

[0167] When the command is an acceleration signal, the inverter output frequency increases; when the command is a deceleration signal, the inverter output frequency decreases.

[0168] The frequency converter or servo drive converts the speed adjustment command into the current frequency and voltage value required to drive the motor, preparing for the motor speed adjustment.

[0169] Step S52: Drive the motor to respond and change its speed.

[0170] The frequency converter or servo driver adjusts the frequency and voltage of the current supplied to the drive motor according to the converted drive signal, so that the actual speed of the drive motor is increased or decreased accordingly.

[0171] The drive motor transmits power to the feed rollers via a coupling, reducer, or belt drive mechanism. The drive motor responds quickly and can complete speed adjustments in a short time, ensuring timely and accurate speed regulation.

[0172] Step S53: Adjust the speed of the belt feeding roller and correct the condition of the belt blank.

[0173] When the rotational speed of the feeding roller 13 is changed, the conveying speed of the strip blank changes accordingly. The specific adjustment process is as follows:

[0174] When the feeding roller 13 accelerates, the conveying speed of the strip blank 14 increases, the slack of the strip blank 14 increases, the supporting force on the contact wheel 6 weakens, and the piston rod of the buffer cylinder 5 extends further under constant air pressure.

[0175] When the conveying roller 13 decelerates, the conveying speed of the strip 14 decreases, the traction effect at the rear end is relatively enhanced, the strip 14 is gradually tightened, the supporting force on the contact wheel 6 is enhanced, and the piston rod of the buffer cylinder 5 gradually retracts to the set range.

[0176] The above correction process forms a closed-loop feedback with the detection of the displacement sensor. After several control cycles, the tension of the strip returns to stability, the real-time displacement value approaches the target displacement value, and the deviation is eliminated or controlled within the allowable range.

[0177] Step S6: Loop control.

[0178] This step involves continuously and in real-time repeating the above detection, comparison, and adjustment processes to form a closed-loop automatic control, ensuring that the strip remains in a stable relaxed state throughout the entire production process without manual intervention. Specifically, it includes the following processes:

[0179] Step S61: Periodic sampling and updating.

[0180] The control device continuously reads the latest real-time displacement signal from the displacement sensor according to a preset sampling period (usually 10 milliseconds to 100 milliseconds, which can be adjusted according to the actual response speed requirements).

[0181] During each sampling cycle, the control device updates the current displacement data and clears the historical data from the previous cycle, ensuring that control decisions are based on the latest strip tension status.

[0182] Step S62: Repeat the deviation calculation and PID adjustment.

[0183] Within each sampling period, the control device automatically repeats the deviation calculation in step S42 and the PID adjustment command generation in step S43.

[0184] That is, the latest acquired real-time displacement value is compared with the target displacement value to calculate the current deviation; then, based on the magnitude and trend of the deviation, a new speed adjustment command is calculated using a PID algorithm. This process is repeated continuously, forming a continuous control loop.

[0185] Step S63: Continuously adjust the speed until it stabilizes and maintains it.

[0186] Each time a new speed adjustment command is generated, the control device immediately executes the speed adjustment according to step S5, driving the feed roller to change its rotational speed accordingly. After continuous adjustment over multiple control cycles, the tension of the strip gradually approaches the target value.

[0187] When the strip slack state stabilizes within the allowable deviation range (i.e., near the target value), the speed adjustment command output by the control device tends to zero or a minimum value, the speed of the feeding roller is maintained at the current level, and the strip is kept in stable conveying.

[0188] If the tension of the strip shifts again due to external disturbances (such as changes in traction speed), the control device will immediately detect the deviation in the new sampling cycle and re-output the adjustment command for correction, thereby always maintaining the stable tension of the strip.

[0189] By repeating the above steps S61 to S63, the automatic speed regulation method of the present invention realizes fully automatic, real-time, closed-loop control of the conveying speed of the strip blank, completely replacing the frequent manual inspection and fine-tuning operations.

[0190] The above is the complete process of the automatic speed adjustment method of the present invention. The method uses a displacement sensor to detect the extension and retraction displacement of the piston rod of the buffer cylinder in real time to sense the tension of the strip blank, and the control device uses a PID closed-loop control algorithm to dynamically adjust the speed of the feeding roller. This achieves stable closed-loop automatic control of the tension during the conveying of the strip blank, without the need for frequent manual intervention. It effectively avoids the strip blank from being too tight and stretching, or too loose and accumulating wrinkles, thus improving production stability and product quality consistency.

[0191] In this embodiment of the invention, to ensure the stability and safety of the automatic speed regulation process, the control device is also equipped with an anomaly handling mechanism, as follows:

[0192] When the displacement sensor 7 detects abnormal fluctuations, sudden changes, or no change for a long time, the control device determines that the sensor is faulty or the signal is abnormal. At this time, it maintains the current drive motor speed unchanged or switches to the preset safe speed and outputs an alarm signal to prompt the operator to check.

[0193] When the displacement value of the buffer cylinder 5 is continuously exceeded by the preset limit range, it is determined that the strip 14 is severely loose or over-tensioned. The control device will limit the speed adjustment range or perform gradual deceleration until the machine stops to prevent the strip from accumulating, wrinkling or being damaged by stretching.

[0194] When the drive motor or the blank conveying power unit 11 reports an abnormality (such as overload, stall, or communication interruption), the control device prioritizes the shutdown protection and records the fault information.

[0195] When the displacement signal is in a high-frequency oscillation state, the control device suppresses frequent speed regulation by delaying the judgment or expanding the allowable fluctuation range, thereby avoiding system oscillation.

[0196] By employing the above-mentioned anomaly handling strategies, the anti-interference capability and operational reliability of the automatic speed control system can be effectively improved, ensuring the continuous and stable conveying of the billet.

[0197] The advantages of this invention are as follows: First, relying on real-time detection by displacement sensors and PID closed-loop automatic speed regulation, the production process eliminates the need for manual periodic inspections and frequent fine-tuning of the conveyor speed, saving dedicated adjustment personnel and significantly reducing the labor intensity of operators. Second, the configuration of horizontal and vertical adjustment slides allows for flexible adjustment of the horizontal position and vertical height of the contact wheel, adapting to different diameters and heights of water hose blanks, thus having a wide range of applications. Third, the use of U-shaped clamps for tool-free clamping and fixing allows for direct and quick installation on existing conveyor racks, facilitating disassembly, relocation, and upgrading of existing old production lines. Finally, the use of a buffer cylinder ensures that the contact wheel maintains constant pressure against the conveyor blank, allowing for real-time sensing of changes in conveyor blank tension. Combined with precise PID closed-loop speed regulation, this effectively prevents the conveyor blank from being too tight and deformed or too loose and wrinkled, ensuring continuous and stable production.

[0198] In summary, the speed control device and method of the present invention can completely replace manual repeated observation and fine-tuning of speed, reduce the workload of operators, improve product quality consistency, and have important industrial application value.

[0199] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An automatic speed control system for active conveying of billets, characterized in that, The speed control system includes a strip conveyor, a strip feeding roller device, a detection device, and a control device. Both the feeding roller device and the detection device are mounted on the strip conveyor frame, with the detection device located upstream of the feeding roller device along the strip conveying direction. The belt feeding roller device includes a belt feeding roller and a strip conveying power unit. The strip conveying power unit is used to drive the belt feeding roller to rotate so as to actively convey the strip. The detection device includes a buffer cylinder, a contact wheel, and a displacement sensor, with the contact wheel mounted on the end of the piston rod of the buffer cylinder; The contact wheel contacts the surface of the strip under the action of the buffer cylinder, and its displacement changes with the tension of the strip. The displacement sensor is used to detect the displacement change and output a detection signal. The control device is electrically connected to both the detection device and the belt feeding roller device, and is used to adjust the conveying speed of the belt feeding roller device according to the detection results of the detection device.

2. The automatic speed control system for active conveying of billets according to claim 1, characterized in that, The detection device also includes a horizontal adjustment slide and a vertical adjustment slide; The transverse adjustment slide is used to adjust the position of the contact wheel in the strip width direction; The vertical adjustment slide is used to adjust the height position of the contact wheel in the vertical direction.

3. The automatic speed control system for active conveying of billets according to claim 2, characterized in that, The lateral adjustment slide includes a linear guide rail, a two-way lead screw, and two lateral sliders; The bidirectional lead screw has two sections of threads with opposite directions of rotation, which respectively engage with the threads of two transverse sliders to drive the two transverse sliders to move synchronously towards or away from each other. One end of the lateral adjustment slide is provided with a lateral adjustment handwheel, which is connected to the bidirectional lead screw drive.

4. The automatic speed control system for active conveying of billets according to claim 3, characterized in that, There are two vertical adjustment slides, which are respectively installed on the two horizontal sliders of the horizontal adjustment slide; Each vertical adjustment slide includes a lead screw, a vertical slider, and a vertical guide rail, and the buffer cylinder is mounted on the vertical slider of the vertical adjustment slide; The upper end of the vertical adjustment slide is provided with a vertical adjustment handwheel, which is connected to the lead screw drive.

5. The automatic speed control system for active conveying of billets according to claim 4, characterized in that, The displacement sensor is installed on one of the vertical adjustment slides and is used to detect the extension and retraction displacement of the piston rod of the corresponding buffer cylinder.

6. The automatic speed control system for active conveying of billets according to claim 1, characterized in that, The detection device is mounted on the strip conveyor frame via a fixed bracket. The fixed bracket has U-shaped clamps at both ends. The U-shaped clamps have a side-opening structure and are equipped with adjusting screws. The adjusting screws are used to tighten the crossbeam of the strip conveyor frame to achieve detachable clamping and fixing.

7. The automatic speed control system for active conveying of billets according to any one of claims 1 to 6, characterized in that, The control device includes a controller and a drive control unit; The controller uses a PID closed-loop control algorithm based on the detection signal from the displacement sensor to generate speed control commands to adjust the rotational speed of the conveyor roller.

8. An automatic speed control method for active conveying of billets, implemented based on the automatic speed control system for active conveying of billets as described in claim 7, characterized in that, The speed regulation method includes: S1: The contact wheel contacts the strip blank and generates displacement as the strip blank tension changes. The displacement sensor detects the extension and retraction displacement of the piston rod of the buffer cylinder to obtain the displacement signal corresponding to the tension state of the strip blank. S2: Compare the displacement signal with the preset target displacement value and calculate the deviation value; S3: Determine whether the strip is in a relaxed or tense state based on the magnitude and sign of the deviation value; S4: When the deviation exceeds the preset threshold, a speed adjustment command is generated based on the PID closed-loop control algorithm; S5: Adjust the rotational speed of the belt feeding roller according to the speed adjustment command to change the belt blank conveying speed and make the belt blank tension state tend to the target displacement value. S6: Repeat steps S1 to S5 to form a closed-loop control.

9. The automatic speed regulation method for active conveying of billets according to claim 9, characterized in that, Step S3 includes: When the deviation value is greater than zero, the strip is determined to be in a relaxed state; When the deviation value is less than zero, the strip is determined to be in a tensioned state; When the deviation is within the preset error range, the current conveying speed remains unchanged.

10. The automatic speed regulation method for active conveying of billets according to claim 9, characterized in that, The step S1 is preceded by a device installation and position adjustment step: The tool-free clamping and fixing of the bracket to the blank conveyor is achieved by using a U-shaped clamp; Operate the lateral adjustment handwheel of the lateral adjustment slide to adjust the lateral distance between the two contact wheels to match the billet diameter; Operate the vertical adjustment handwheel of the vertical adjustment slide to adjust the vertical height of the contact wheel to match the laying height of the strip.

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