A method and device for collecting the position of steel sections on a conveyor chain without an encoder

Abstract

The present invention discloses an encoder-free method and device for measuring the position of steel sections on a conveyor chain. The device comprises a motor, the outer circumference of the motor's output shaft being sleeved with a metal ring. The outer circumference of the metal ring is uniformly connected to a number of detection rods along its circumference. The end of the motor is connected to a dust cover, the top surface of which is connected to a proximity switch. The front end of the motor's output shaft is connected to the input of a reduction gearbox, and the output of the reduction gearbox is connected to a driving sprocket. The driving sprocket is connected to a driven sprocket via a conveyor chain, the upward section of which carries the steel sections. The method of the present invention measures the displacement of the steel sections on the conveyor chain by the linear velocity of the motor output side per unit time. The present invention overcomes the problem in existing methods for measuring the position of steel sections on conveyor chains, where the detection elements are unable to withstand the influence of harsh environments and may malfunction or become damaged. This method improves production efficiency, reduces production costs, and ensures safe production.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrical control, and in particular relates to a method and device for collecting the position of section steel on a conveyor chain without an encoder. Background Art

[0002] In metallurgical production, steel sections are usually transported to the next process via a conveyor chain. The conveyor chain is mainly composed of chains, sprockets, drive motors, and reduction gearboxes. To ensure the safe and stable operation of the steel sections during transportation, it is necessary to promptly understand the position of the steel sections during transportation and transmit this position information to the controller, which controls the drive motor and thus the entire operation of the conveyor chain. In order to accurately collect the position of the steel sections on the conveyor chain, an encoder is usually installed at the tail of the drive motor as a detection element of the control system. However, as a precision component, the encoder is prone to abnormalities or damage when operating for a long time in harsh environments (such as vibration, moisture, dust, and strong electromagnetic interference), which has a significant impact on the continuity and stability of production.

[0003] The Chinese patent specification discloses a method and system for detecting the posture of profiles on a heavy-duty palletizer conveyor chain (publication number CN 117361083 A), and specifically discloses the following: obtaining a first time group for the profile to pass through a first set of reference points at the beginning of the conveyor chain detection section and a second time group for the profile to pass through a second set of reference points at the end; calculating the total time between each two reference points corresponding to the positions of the first and second reference points of the conveyor chain detection section to obtain several sets of real time; comparing the real time with the preset first time, and adjusting the first posture of the profile based on the comparison result; calculating the time interval between two adjacent profiles passing through the second set of reference points, comparing the time interval with the preset standard interval, and adjusting the second posture of the profile based on the comparison result. This invention can obtain the posture of profiles on the conveyor chain and the step distance of the front and rear profiles, but it uses cameras and electromagnetic sensors to achieve profile posture detection. The cameras and electromagnetic sensors are in harsh on-site environments and are also prone to abnormalities or damage, which can affect production. Summary of the Invention

[0004] 1. Technical Problems to be Solved

[0005] The present invention proposes a method and device for collecting the position of steel sections on a conveyor chain without an encoder, the purpose of which is to solve the problem that the detection elements of the existing conveyor chain cannot withstand the influence of harsh environments and become abnormal or damaged, thereby affecting normal production.

[0006] 2. Technical Solution

[0007] In order to achieve the above objectives, the present invention adopts the following technical solutions.

[0008] The device used in the encoder-free conveyor chain position collection method of the present invention includes a motor, the outer circle of the motor output shaft is sleeved with a metal ring, the outer peripheral surface of the metal ring is evenly connected to a plurality of detection rods along its circumference, the end of the motor is connected to a dust cover, and the top surface inside the dust cover is connected to a proximity switch; the front end of the motor output shaft is connected to the input end of the reduction gearbox, the output end of the reduction gearbox is connected to a driving sprocket, the driving sprocket is connected to a driven sprocket through a conveyor chain, and the upward section of the conveyor chain carries the steel.

[0009] As a method for acquiring the position of steel sections on a conveyor chain without an encoder of the present invention, the displacement of the steel sections on the conveyor chain is obtained by the linear velocity of the motor output side per unit time, and specifically includes the following steps:

[0010] S1, start the motor, and the motor enters soft start;

[0011] S2: Whether the proximity switch detects the detection rod, if "no", proceed to the next step, if "yes", proceed to step S4;

[0012] S3, the displacement of steel section ΔS is calculated as follows:

[0013]

[0014] Where: i is the reduction ratio of the reduction gearbox; Δt q The time t0 from when the motor obtains the maximum starting current to the time t1 when the proximity switch detects the first detection rod, that is, Δt q =t1-t0;Δv q is the linear velocity of the detection rod passing the proximity switch, i.e. Δv q =Δt q ×a; a is acceleration, that is, v n is the rated linear speed of the motor output side, that is n n is the rated speed of the motor, v0 is the initial linear velocity 0 when the motor starts, t qn is the soft start time set by the motor parameters; r1 is the radius of the motor output shaft, and r2 is the pitch circle radius of the driving sprocket;

[0015] S4, the displacement of steel ΔS is calculated as follows:

[0016]

[0017] Where: v n is the rated linear speed of the motor output side, that is n n is the rated speed of the motor; t nThe time interval between two adjacent detection rods passing the proximity switch in sequence at the rated speed of the motor is t n =60 / m*n n , m is the number of detection rods; k is the correction coefficient, that is, t act The actual interval time between two adjacent detection rods passing through the proximity switch in sequence;

[0018] S5, when the motor starting time T>t qn When the correction coefficient k is equal to 1, if "yes", the soft start is successful, and the process returns to step S4; if "no", the process proceeds to the next step;

[0019] S6, soft start fails, the motor restarts.

[0020] The proximity switch and current transformer are electrically connected to a PLC programmable controller.

[0021] The PLC programmable controller is connected to a display to display the position of the steel sections on the conveyor chain.

[0022] 3. Beneficial Effects

[0023] This invention uses the linear velocity of the motor output side per unit time to measure the displacement of steel sections on the conveyor chain. This overcomes the problem in existing methods of measuring the position of steel sections on conveyor chains, where the detection elements are unable to withstand harsh environments and may malfunction or become damaged. This improves production efficiency, reduces production costs, and ensures safe production. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The diagram is a schematic diagram of the main structure of the encoder-free steel position acquisition device on the conveyor chain of the present invention.

[0025] Figure 2 yes Figure 1 Schematic diagram of the structure after removing the reduction gearbox (removing the front side panel of the dust cover).

[0026] Figure 3 yes Figure 2 Schematic diagram of the three-dimensional structure (removing the left side panel of the dust cover).

[0027] Figure 4 The present invention is a flow chart of a method for collecting the position of section steel on a conveyor chain without an encoder. DETAILED DESCRIPTION

[0028] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can have a clearer understanding.

[0029] Example 1

[0030] like Figure 1 、 Figure 2 、 Figure 3 As shown, the device used in the method for collecting the position of steel sections on the conveyor chain without an encoder in this embodiment includes a motor 1, the power of the motor is 55KW, and the rated speed is n n The speed is 735 rpm, and the output shaft radius r1 is 40 mm; the outer circle of the output shaft 2 of the motor is sleeved with a metal ring 3, and the outer peripheral surface of the metal ring is evenly connected to four detection rods 4 along its circumference; the end of the motor is connected to the dust cover 6, and the top surface inside the dust cover is connected to the proximity switch 5; the front end of the output shaft 2 of the motor is connected to the input end of the reduction gearbox 7, and the reduction ratio i of the reduction gearbox is 35.71; the output end of the reduction gearbox is connected to the driving sprocket 8, and the pitch circle radius r2 of the driving sprocket is 261.3 mm. The driving sprocket is connected to the driven sprocket 10 through the conveyor chain 9, and the upward section of the conveyor chain carries the steel section 11.

[0031] like Figure 4 As shown, the encoder-free method for collecting the position of steel sections on a conveyor chain in this embodiment includes the following specific steps:

[0032] S1, start motor 1, the motor enters soft start;

[0033] S2. If the proximity switch 5 does not detect the detection rod 4, proceed to the next step. If the proximity switch 5 detects the detection rod 4, proceed directly to step S4.

[0034] S3 and the displacement of steel 11 are calculated as follows:

[0035]

[0036] Where: i is the reduction ratio of the reduction box 7; Δt q The time t0 from when the motor obtains the maximum starting current to the time t1 when the proximity switch 5 detects the first detection rod 4, that is, Δt q =t1-t0;Δv q is the linear velocity of the detection rod 4 passing the proximity switch 5, i.e. Δv q =Δt q ×a; a is acceleration, that is, v n is the rated linear speed of the motor output side, that is n n is the rated speed of the motor, v0 is the initial linear velocity 0 when the motor 1 starts, t qn The soft start time set for motor 1 parameters; r1 is the radius of the motor output shaft, and r2 is the pitch circle radius of the driving sprocket;

[0037] In this embodiment, the reduction ratio i of the reduction box is 35.71; the output shaft radius r1 is 40 mm; the pitch circle radius r2 of the driving sprocket is 261.3 mm; the soft start time t of the motor parameter setting is qn 10 seconds;

[0038] By solving Δv q To obtain the acceleration a when the motor starts, it is necessary to first calculate the rated speed n of the motor output side. n Linear speed Depend on Calculated a=307.876mm / s 2 , so, according to formula (1) (In this embodiment, the time from t0 when the PLC controller detects that the motor obtains the maximum starting current to t1 when the proximity switch detects the first detection rod, that is, t1-t0 is 0.4s); the displacement of the steel section 11 ΔS=9.01mm is input into the accumulator;

[0039] S4. Calculate the displacement ΔS of the steel section 11 by the following formula:

[0040]

[0041] Where: v n is the linear velocity of the output side of motor 1 at rated speed, that is, n n is the rated speed of the motor; t n is the interval time between two adjacent detection rods 4 passing the proximity switch 5 in sequence at the rated speed of the motor, that is, t n =60 / m*n n , m is the number of detection rods; k is the correction coefficient, that is, t act The actual interval time between two adjacent detection rods 4 passing through the proximity switch 5 in sequence;

[0042] According to the above, the rated linear speed of the motor is v n =3078.76mm / s; the reduction ratio i of the reduction gearbox is 35.71; the output shaft radius r1 is 40mm; the pitch circle radius r2 of the driving sprocket is 261.3mm; t n =60 / 4×735=0.0204 seconds (In this embodiment, there are 4 detection rods and the rated speed of the motor is n n =735 rpm); correction factor Known t n The actual interval time t between two adjacent detection rods passing through the proximity switch is 0.0204 seconds. actis 0.022 seconds, so the correction coefficient k is 0.9273, and the displacement of the steel section is obtained. The displacement of the steel section 11, ΔS = 10.6541 mm, is input into the accumulator;

[0043] S5, when the starting time of motor 1 T>t qn When the correction coefficient k is equal to 1, the soft start is successful, and step S4 is continued until the conveying process is completed; if the correction coefficient k is less than 1, the next step is entered;

[0044] S6. Soft start fails and motor 1 restarts.

[0045] In this embodiment, the power input end of the motor is connected to a current sensor, and the output of the current sensor and the output of the proximity switch are electrically connected to the PLC programmable controller; the current transformer is controlled by the PLC programmable controller; the PLC programmable controller is connected to a display to display the position of the steel section on the conveyor chain.

[0046] This invention uses the linear velocity of the motor output side per unit time to measure the displacement of steel sections on the conveyor chain. This overcomes the problem in existing methods of measuring the position of steel sections on conveyor chains, where the detection elements are unable to withstand harsh environments and may malfunction or become damaged. This improves production efficiency, reduces production costs, and ensures safe production.

[0047] The present invention is not limited to the above-mentioned specific embodiments. Various improvements made by those skilled in the art to the technical solution based on the concept of the present invention should fall within the scope of protection required by the present invention.

Claims

1. A method for collecting the position of steel sections on a conveyor chain without an encoder, comprising a motor (1), an output shaft (2) of the motor having an outer circle sleeved with a metal ring (3), an outer peripheral surface of the metal ring being evenly connected to a plurality of detection rods (4) along its circumference, an end of the motor being connected to a dust cover (6), and a top surface inside the dust cover being connected to a proximity switch (5); a front end of the output shaft (2) of the motor being connected to an input end of a reduction gearbox (7), an output end of the reduction gearbox being connected to a driving sprocket (8), and the driving sprocket being connected to a driven sprocket (10) via a conveyor chain (9); an upward section of the conveyor chain carrying steel sections (11), characterized in that The displacement of the steel section on the conveyor chain is obtained by the linear velocity of the motor output side per unit time, which specifically includes the following steps: S1, start the motor, and the motor enters soft start; S2, whether the proximity switch detects the detection rod, if "no", go to the next step, if "yes", go to step S4; S3, the calculation formula of the displacement of the steel section ΔS is as follows: Where: i is the reduction ratio of the reduction gearbox; Δt q The time t0 from when the motor obtains the maximum starting current to the time t1 when the proximity switch detects the first detection rod, that is, Δt q =t1-t0;Δv q is the linear velocity of the detection rod passing the proximity switch, i.e. Δv q =Δt q ×a; acceleration a is v n is the rated linear speed of the motor output side, that is n n is the rated speed of the motor; v0 is the initial linear velocity 0 when the motor starts; t qn is the soft start time set by the motor parameters; r1 is the radius of the motor output shaft, and r2 is the pitch circle radius of the driving sprocket; S4, the calculation formula of the displacement of the steel section ΔS is as follows: Where: t n The time interval between two adjacent detection rods passing the proximity switch in sequence at the rated speed of the motor is t n =60 / m*n n , m is the number of detection rods; k is the correction coefficient, that is, t act The actual interval time between two adjacent detection rods passing through the proximity switch in sequence; S5, when the motor starting time T>t qn When the correction coefficient k is equal to 1, if "yes", the soft start is successful, and the process returns to step S4; if "no", the process proceeds to the next step; S6, soft start fails, the motor restarts.

2. The method for collecting the position of section steel on a conveyor chain according to claim 1, characterized in that: The proximity switch and current transformer are electrically connected to a PLC programmable controller.

3. The method for collecting the position of section steel on a conveyor chain according to claim 2, characterized in that: The PLC programmable controller is connected to a display to display the position of the steel sections on the conveyor chain.

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