A feedback self-regulating system based on servo electric cylinder

Abstract

The embodiment of the present invention discloses a feedback self-adjusting system based on a servo electric cylinder, which relates to the field of automatic control technology. The system includes: a servo electric cylinder, a servo motor and a controller; the servo motor is connected to the power end of the servo electric cylinder, and the controller is connected to the control end of the servo motor; a plurality of encoders are installed at the end of the lead screw of the servo electric cylinder, and the plurality of encoders are coaxially installed, and the encoder is used to measure the lead screw displacement of the servo electric cylinder, and output the collected lead screw displacement as a counting pulse value; the controller is connected to the output end of the plurality of encoders, and the controller feedback controls the push rod speed of the servo electric cylinder according to the values ​​output by the plurality of encoders. The present invention can automatically control the push rod speed of the servo electric cylinder, reduce the internal physical impact, and increase the service life of the equipment.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic control, and in particular relates to a feedback self-regulating system based on a servo electric cylinder. Background Art

[0002] The servo electric cylinder is a modular product that integrates the servo motor and the lead screw. It converts the rotary motion of the servo motor into linear motion. At the same time, it converts the best advantages of the servo motor - precise speed control, precise revolution control, and precise torque control - into precise speed control, precise position control, and precise force control, realizing a new series of high-precision linear motion products. With the rapid development of science and technology, servo electric cylinders are widely used in many equipment industries, mainly in the fields of experimental equipment, special equipment, precision press-fitting equipment, and other places that can replace hydraulic and pneumatic equipment. It is an upgraded product of hydraulic and pneumatic equipment.

[0003] During the operation of the servo electric cylinder, the current push rod speed control method of the servo electric cylinder can control the push rod to run to the specified position after receiving the operation command. However, during the whole process, this type of control method allows the push rod to move at a uniform and rapid speed. When the push rod is required to run to the cylinder limit, the push rod is still running rapidly, which causes the push rod to easily collide with the cylinder or cause a physical impact on the cylinder, thereby reducing the service life of the servo electric cylinder. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a feedback self-adjusting system based on a servo electric cylinder, which is used to solve the problem that the existing servo electric cylinder push rod speed control method is prone to physical collision between the push rod and the cylinder body or physical impact on the cylinder body, thereby reducing the service life of the servo electric cylinder. The present invention can collect the displacement of the servo electric cylinder lead screw in real time, and automatically control the push rod speed of the servo electric cylinder according to the displacement, reducing the physical impact inside the device and increasing the service life of the equipment.

[0005] The embodiment of the present invention provides a feedback self-adjusting system based on a servo electric cylinder, comprising: a servo electric cylinder, a servo motor and a controller; the servo motor is connected to a power end of the servo electric cylinder, and the controller is connected to a control end of the servo motor;

[0006] A plurality of encoders are installed at the end of the lead screw of the servo electric cylinder, and the plurality of encoders are coaxially installed. The encoders are used to measure the lead screw displacement of the servo electric cylinder and output the collected lead screw displacement as a counting pulse value;

[0007] The controller is connected to the output ends of the multiple encoders, and the controller feedback controls the push rod speed of the servo electric cylinder according to the values ​​output by the multiple encoders.

[0008] In an optional embodiment, the controller is specifically used to adjust the speed of the push rod of the servo electric cylinder to 0 when the push rod reaches the limit.

[0009] In an optional embodiment, the feedback self-adjusting system based on the servo electric cylinder further includes: a spraying device;

[0010] The spraying device includes a paint tank, an output pipe, a spraying arm and a control valve. The paint inlet of the spraying arm is connected to the outlet of the paint tank through the output pipe. The control valve is installed on the output pipe. The controller is connected to the control end of the control valve.

[0011] The push rod end of the servo electric cylinder is mechanically connected to the spray arm, and the servo electric cylinder is used to drive the spray arm to move so as to spray the inner wall of the spray pipe.

[0012] In an optional embodiment, the spray arm is in the form of a straight pipe, and a paint nozzle is provided on the front end side wall of the spray arm; the servo electric cylinder is used to drive the spray arm to move along the central axis direction of the pipe to be sprayed.

[0013] In an optional embodiment, the spraying device further comprises:

[0014] A track, arranged on the central axis of the pipeline to be sprayed;

[0015] A rotating table is mounted on the track via a slider and can rotate around the track;

[0016] The servo electric cylinder is installed on the rotating platform, the front end of the spraying arm is a paint nozzle, and the servo electric rod is used to drive the spraying arm to move radially along the pipeline to be sprayed.

[0017] In an optional embodiment, the spraying device further includes: a heater disposed on the spraying arm.

[0018] In an optional embodiment, the controller includes:

[0019] A data processing unit, configured to remove values ​​with large differences among the values ​​generated by the multiple encoders at the current moment, to obtain a set of values ​​to be integrated;

[0020] A data integration unit, used for performing multi-data integration on the value set to be integrated to obtain an integrated angle;

[0021] A speed control unit is used to determine the push rod control speed of the servo electric cylinder according to the integrated rotation angle, and control the push rod of the servo electric cylinder to move at the determined push rod control speed.

[0022] In an optional embodiment, the data processing unit determines the value of the encoder that needs to be eliminated at the current moment according to the first formula, and eliminates the value of the encoder that needs to be eliminated from the values ​​output by the multiple encoders received at the current moment to obtain a set of values ​​to be integrated;

[0023] The first formula is:

[0024]

[0025] Where I(t) represents the value of the I(t)th encoder that needs to be removed at the current moment; t represents the current moment; Z i (t) represents the number of positive pulses of the i-th encoder received cumulatively at the current moment; F i (t) represents the number of inversion pulses of the i-th encoder received cumulatively at the current moment; n represents the total number of encoders installed at the end of the lead screw of the servo electric cylinder; a represents an integer variable, and its value range is [1, n]; | | represents the absolute value; It means to substitute the value of i from 1 to n into the brackets to obtain the value of i that makes the formula in the brackets reach the maximum value;

[0026] The data integration unit is specifically used to perform multi-data integration on the set of values ​​to be integrated according to the second formula to obtain an integrated angle;

[0027] The second formula is:

[0028]

[0029] Where θ(t) represents the integrated rotation angle; It means to substitute the values ​​of i from 1 to n but not to I(t) into the brackets to find the mode of all the substituted values; It means that the value of i from 1 to n but not I(t) is substituted into the brackets and the sum of all the substituted values ​​is calculated; It means that the value of a from 1 to n but not I(t) is substituted into the brackets to obtain the product of all the substituted values; M represents the total number of pulses output by the encoder in one forward rotation;

[0030] The speed control unit is specifically used to determine the push rod control speed of the servo electric cylinder according to a third formula;

[0031] The third formula is:

[0032]

[0033] Wherein, V(t) represents the push rod control speed of the servo electric cylinder at the current moment; V Mrepresents the maximum controllable push rod speed of the servo electric cylinder; L0 represents the actual extension length of the push rod of the servo electric cylinder when it is in the initial position, which is half of the longest extension distance of the push rod of the servo electric cylinder; r represents the radius of the transmission gear between the servo electric cylinder and the push rod.

[0034] The present invention provides a feedback self-adjusting system based on a servo electric cylinder. First, multiple encoders are installed at the end of the lead screw of the servo electric cylinder to collect and measure the lead screw displacement of the servo electric cylinder, and the collected lead screw displacement is output as a count pulse value. Finally, according to the values ​​output by the multiple encoders, the push rod speed of the servo electric cylinder is feedback-controlled. The present invention can automatically control the push rod of the servo electric cylinder to reach the limit and adjust its speed to a relatively small value (such as 0), which effectively reduces the physical impact inside the servo electric cylinder and improves the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 A schematic structural diagram of a feedback self-regulating system based on a servo electric cylinder provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0037] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0038] It should be clear that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Figure 1 A schematic diagram of the structure of a feedback self-adjusting system based on a servo electric cylinder provided by an embodiment of the present invention. Figure 1 , the system comprises: a servo electric cylinder 1, a servo motor 2 and a controller 3;

[0040] The servo motor 2 is connected to the power end of the servo electric cylinder 1 , and the controller 3 is connected to the control end of the servo motor 2 .

[0041] A plurality of encoders 5 are installed at the end of the lead screw 4 of the servo electric cylinder, and the plurality of encoders 5 are installed coaxially. The encoders 5 are used to measure the displacement of the lead screw 4 of the servo electric cylinder, and output the collected displacement of the lead screw 4 as a counting pulse value.

[0042] The controller 3 is connected to the output ends of the multiple encoders 5, and the controller 3 feedback controls the speed of the push rod 6 of the servo electric cylinder 1 according to the values ​​output by the multiple encoders. Preferably, the controller 3 is specifically used to adjust the speed of the push rod 6 of the servo electric cylinder 1 to 0 when the push rod 6 reaches the limit.

[0043] The beneficial effects of the above technical solution are as follows: first, multiple encoders are installed at the end of the lead screw of the servo electric cylinder to collect and measure the lead screw displacement of the servo electric cylinder, and the collected lead screw displacement is output as a count pulse value, and finally, the push rod speed of the servo electric cylinder is feedback-controlled according to the values ​​output by the multiple encoders. The present invention can automatically control the push rod of the servo electric cylinder to a relatively small value (such as 0) when it reaches the limit, effectively reducing the physical impact inside the servo electric cylinder and prolonging the service life of the equipment.

[0044] As an optional embodiment, the feedback self-regulating system based on the servo electric cylinder further includes a spraying device, which includes a paint cylinder, an output pipe, a spraying arm and a control valve. The paint inlet of the spraying arm is connected to the outlet of the paint cylinder through the output pipe, and the control valve is installed on the output pipe; the controller is connected to the control end of the control valve. The push rod end of the servo electric cylinder is mechanically connected to the spraying arm, and the servo electric cylinder is used to drive the spraying arm to move so as to spray the inner wall of the spraying pipe.

[0045] In an optional embodiment, the spray arm is in the form of a straight pipe, and a paint nozzle is provided on the front end side wall of the spray arm; the servo electric cylinder is used to drive the spray arm to move along the central axis direction of the pipe to be sprayed.

[0046] The beneficial effects of the above technical solution are as follows: a spraying device is arranged at the end of the push rod of the servo electric cylinder, so that the paint in the paint cylinder can be transported to the spray arm through the output pipe and the control valve in sequence, and the spray arm is pushed by the push rod of the servo electric cylinder to move along the central axis direction of the pipe to be sprayed, and the paint is controlled to be sprayed out from the nozzle on the side of the spray arm, so as to realize the spraying of the inner wall of the pipe to be sprayed, thereby completing the spraying operation of the paint, effectively improving the work efficiency, and solving the problem of inconvenience in spraying the inner wall of a smaller pipe.

[0047] In another optional embodiment, the spraying device further comprises:

[0048] A track, arranged on the central axis of the pipeline to be sprayed;

[0049] A rotating table is mounted on the track via a slider and can rotate around the track;

[0050] The servo electric cylinder is installed on the rotating platform, the front end of the spraying arm is a paint nozzle, and the servo electric rod is used to drive the spraying arm to move radially along the pipeline to be sprayed.

[0051] The beneficial effect of the above technical solution is: when the diameter of the pipe to be sprayed is relatively large, the servo electric cylinder can be installed on the rotating table on the track. The servo electric cylinder is installed on the rotating table, and the servo electric cylinder can move along the direction of the track and can rotate 360° around the track. The servo electric cylinder controls the spray arm also installed on the rotating table to move radially along the pipe to be sprayed, so that the distance between the front end of the spray arm and the inner wall of the pipe to be sprayed can be adjusted to a suitable distance. At this time, the control valve is opened to spray the paint from the paint nozzle at the front end of the spray arm onto the inner wall of the pipe to be sprayed. When the rotating table rotates around the track, annular spraying of the inner wall of the pipe to be sprayed can be achieved. The spraying position is convenient to control, and the problems of poor manual spraying effect and low efficiency are effectively saved.

[0052] As an optional embodiment, the spraying device further comprises: a heater arranged on the spraying arm. The beneficial effect of this technical solution is: the heater is arranged on the spraying arm, so that the paint sprayed onto the inner wall of the pipe can be heated to accelerate the drying speed of the paint.

[0053] As an optional embodiment, the controller 3 includes:

[0054] The data processing unit is used to remove the values ​​with large differences among the values ​​generated by the multiple encoders at the current moment to obtain a set of values ​​to be integrated. Preferably, the data processing unit determines the value of the encoder to be removed at the current moment according to the first formula, and removes the value of the encoder to be removed from the values ​​output by the multiple encoders received at the current moment to obtain the set of values ​​to be integrated;

[0055] The first formula is:

[0056]

[0057] Where I(t) represents the value of the I(t)th encoder that needs to be removed at the current moment; t represents the current moment; Z i (t) represents the number of positive pulses of the i-th encoder received cumulatively at the current moment; F i (t) represents the number of inversion pulses of the i-th encoder received cumulatively at the current moment; n represents the total number of encoders installed at the end of the lead screw of the servo electric cylinder; a represents an integer variable, and its value range is [1, n]; | | represents the absolute value; It means substituting the value of i from 1 to n into the brackets to obtain the value of i that makes the formula in the brackets reach the maximum value.

[0058] A data integration unit is used to perform multi-data integration on the value set to be integrated to obtain an integrated angle. Preferably, the data integration unit is specifically used to perform multi-data integration on the value set to be integrated according to a second formula to obtain an integrated angle;

[0059] The second formula is:

[0060]

[0061] Where θ(t) represents the integrated rotation angle; It means to substitute the values ​​of i from 1 to n but not to I(t) into the brackets to find the mode of all the substituted values; It means that the value of i from 1 to n but not I(t) is substituted into the brackets and the sum of all the substituted values ​​is calculated; It means that the value of a is taken from 1 to n and does not reach / (t) and is substituted into the brackets to obtain the product of all the substituted values; M represents the total number of pulses output by the encoder in one forward rotation.

[0062] A speed control unit is used to determine the push rod control speed of the servo electric cylinder according to the integrated rotation angle, and control the push rod of the servo electric cylinder to move at the determined push rod control speed. Preferably, the speed control unit is specifically used to determine the push rod control speed of the servo electric cylinder according to a third formula;

[0063] The third formula is:

[0064]

[0065] Wherein, V(t) represents the push rod control speed of the servo electric cylinder at the current moment; V M represents the maximum controllable push rod speed of the servo electric cylinder; L0 represents the actual extension length of the push rod of the servo electric cylinder when it is in the initial position, which is half of the longest extension distance of the push rod of the servo electric cylinder; r represents the radius of the transmission gear between the servo electric cylinder and the push rod.

[0066] The beneficial effects of the above technical solution are as follows: using the first formula, the value of the encoder that needs to be eliminated at the current moment is determined, and then the value is eliminated, so that the values ​​with large differences in the multi-turn encoder values ​​are eliminated, ensuring the reliability of calculation and control; then, based on the value of the multi-turn encoder after elimination and the second formula, multiple data are integrated to obtain the integrated rotation angle of the multi-turn encoder, and a new multi-angle integration method is used at the same time, so that when there are multiple identical data, the mode is taken, making the integration more specific and accurate; finally, using the third formula, the push rod speed of the servo electric cylinder is controlled according to the real-time push rod position of the servo electric cylinder, so that the speed can be reduced to 0 when the push rod reaches the limit, reducing the physical impact inside the servo electric cylinder and increasing the service life of the equipment.

[0067] From the content of the above embodiment, it can be known that, firstly, the displacement of the lead screw of the servo electric cylinder is collected and measured by installing multiple encoders at the end of the lead screw of the servo electric cylinder, and the collected lead screw displacement is output as a count pulse value, then the value of the encoder with the largest difference is deleted, and then the multiple data are integrated to obtain the integrated angle, and finally the push rod control speed is obtained according to the integrated angle and the third formula, and further, the servo electric cylinder is controlled to operate according to the push rod control speed. The present invention can delete possible erroneous data, ensure the accuracy of the calculation results, and automatically control the push rod speed of the servo electric cylinder, thereby effectively reducing the physical impact inside the servo electric cylinder and improving the service life of the equipment.

[0068] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0069] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0070] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0071] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these changes and variations. The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A feedback self-adjusting system based on a servo electric cylinder, It is characterized in that include: A servo electric cylinder, a servo motor and a controller; the servo motor is connected to the power end of the servo electric cylinder, and the controller is connected to the control end of the servo motor; A plurality of encoders are installed at the end of the lead screw of the servo electric cylinder, and the plurality of encoders are coaxially installed. The encoders are used to measure the lead screw displacement of the servo electric cylinder and output the collected lead screw displacement as a counting pulse value; The controller is connected to the output ends of the multiple encoders, and the controller feedback controls the push rod speed of the servo electric cylinder according to the values ​​output by the multiple encoders; Wherein, the controller is specifically used to adjust the speed of the push rod of the servo electric cylinder to 0 when the push rod reaches the limit; Wherein, the controller comprises: A data processing unit, configured to remove values ​​with large differences among the values ​​generated by the multiple encoders at the current moment, to obtain a set of values ​​to be integrated; A data integration unit, used for performing multi-data integration on the value set to be integrated to obtain an integrated angle; A speed control unit, used for determining a push rod control speed of the servo electric cylinder according to the integrated rotation angle, and controlling the push rod of the servo electric cylinder to move at the determined push rod control speed; The data processing unit specifically determines the value of the encoder that needs to be eliminated at the current moment according to the first formula, and eliminates the value of the encoder that needs to be eliminated from the values ​​output by the multiple encoders received at the current moment to obtain a set of values ​​to be integrated; The first formula is: Where I(t) represents the value of the I(t)th encoder that needs to be removed at the current moment; t represents the current moment; Z i (t) represents the number of positive pulses of the i-th encoder received cumulatively at the current moment; F i (t) represents the number of inversion pulses of the i-th encoder received cumulatively at the current moment; n represents the total number of encoders installed at the end of the lead screw of the servo electric cylinder; a represents an integer variable, and its value range is [1, n]; It means to find the absolute value; It means to substitute the value of i from 1 to n into the brackets to obtain the value of i that makes the formula in the brackets reach the maximum value; The data integration unit is specifically used to perform multi-data integration on the set of values ​​to be integrated according to the second formula to obtain an integrated angle; The second formula is: Where θ(t) represents the integrated rotation angle; It means to substitute the values ​​of i from 1 to n but not to I(t) into the brackets to find the mode of all the substituted values; It means that the value of i from 1 to n but not I(t) is substituted into the brackets and the sum of all the substituted values ​​is calculated; It means that the value of a from 1 to n but not I(t) is substituted into the brackets to obtain the product of all the substituted values; M represents the total number of pulses output by the encoder in one forward rotation; The speed control unit is specifically used to determine the push rod control speed of the servo electric cylinder according to a third formula; The third formula is: Wherein, V(t) represents the push rod control speed of the servo electric cylinder at the current moment; V M Indicates the maximum controllable push rod speed of the servo electric cylinder; L 0 It represents the actual extension length of the push rod of the servo electric cylinder when it is in the initial position, which is half of the longest extension distance of the push rod of the servo electric cylinder; r represents the radius of the transmission gear between the servo electric cylinder and the push rod.

2. The feedback self-adjusting system based on the servo electric cylinder as claimed in claim 1, It is characterized in that It also includes a spraying device; the spraying device includes a paint tank, an output pipe, a spraying arm and a control valve, the paint inlet of the spraying arm is connected to the outlet of the paint tank through the output pipe, and the control valve is installed on the output pipe; the controller is connected to the control end of the control valve; The push rod end of the servo electric cylinder is mechanically connected to the spray arm, and the servo electric cylinder is used to drive the spray arm to move so as to spray the inner wall of the spray pipe.

3. The feedback self-adjusting system based on the servo electric cylinder as claimed in claim 2, It is characterized in that The spray arm is in the form of a straight pipe, and a paint nozzle is arranged on the front end side wall of the spray arm; the servo electric cylinder is used to drive the spray arm to move along the central axis direction of the pipe to be sprayed.

4. The feedback self-adjusting system based on the servo electric cylinder as claimed in claim 2, It is characterized in that The spraying device also includes: A track, arranged on the central axis of the pipeline to be sprayed; A rotating table is mounted on the track via a slider and can rotate around the track; The servo electric cylinder is installed on the rotating platform, the front end of the spraying arm is a paint nozzle, and the servo electric rod is used to drive the spraying arm to move radially along the pipeline to be sprayed.

5. The feedback self-adjusting system based on the servo electric cylinder as claimed in claim 2, It is characterized in that The spraying device further includes: a heater arranged on the spraying arm.

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