Method and means for simultaneous measurement of wheel speed and direction of rotation

Abstract

This invention discloses a method and component for synchronously measuring wheel speed and rotation direction. The wheel body rotates synchronously with the wheel end. The outer ring has equally spaced first through holes for speed measurement, and the inner ring has three different circumferentially spaced second through holes arranged in a fixed cyclic sequence. A signal processing unit records the time interval of the pulses from the second through holes, and combines two consecutive intervals in a chronological order to form an ordered combination. This combination is compared with two non-overlapping reference combinations for forward and reverse rotation to determine the direction. Simultaneously, the wheel end speed is calculated from the pulses from the first through holes. The component includes a first wheel and a second wheel fixed parallel to the same rotating shaft, each equipped with two detection elements and a signal processing unit, providing redundant dual-channel comparison output. This invention allows for direct synchronous measurement of speed and direction at the wheel end without requiring a motor-end signal.

Description

Technical Field

[0001] This invention relates to the field of rotational speed and rotational direction detection technology, and in particular to a method and component for synchronously measuring wheel speed and rotational direction. Background Technology

[0002] The speed of belt conveyor pulleys is typically detected by installing a perforated plate at the pulley in conjunction with a sensor. The outer ring of the plate has equally spaced through holes, which pass sequentially through the sensor to generate pulse signals. The pulse frequency reflects the pulley speed. However, the pulse sequence generated by the equally spaced through holes is identical during both forward and reverse rotation, making it impossible to determine the direction of rotation solely based on the pulse signal at the pulley. Current solutions require reading the direction signal from the drive motor and then matching it with the pulley speed signal to indirectly determine the pulley's direction of rotation. This not only increases the complexity of cross-component wiring and signal synchronization calibration but also fails to reflect the true direction of rotation under conditions such as belt slippage or coupling disconnection, where the motor and pulley movements are inconsistent, leading to direction detection failure. Summary of the Invention

[0003] The purpose of this invention is to provide a method and component for synchronously measuring wheel speed and rotation direction, so as to solve the problems pointed out in the background art.

[0004] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A method for synchronously measuring wheel speed and rotation direction includes the following steps: S1. A wheel body that rotates synchronously with the wheel end is adopted. The wheel body has a plurality of first through holes evenly distributed along a first circumferential trajectory and a plurality of second through holes distributed along a second circumferential trajectory. The first circumferential trajectory and the second circumferential trajectory are concentric circles with unequal radii. The circumferential spacing between adjacent holes of the plurality of second through holes on the second circumferential trajectory includes at least three different sizes. When the wheel body rotates with the wheel end, the first through holes sequentially pass through a first detection element to generate a first pulse signal, and the second through holes sequentially pass through a second detection element to generate a second pulse signal. S2. The signal processing unit calculates the wheel end rotation speed based on the pulse frequency or pulse period of the first pulse signal; S3. The signal processing unit records the time intervals between adjacent pulses in the second pulse signal to form a time interval sequence; S4. The signal processing unit takes two consecutive time intervals from the time interval sequence and forms an ordered combination according to the time sequence. After comparing the ordered combination with a preset reference combination, it outputs a direction signal: the ordered combination when the wheel end rotates along the first direction belongs to the first reference combination group, and the ordered combination when the wheel end rotates along the second direction belongs to the second reference combination group. The first reference combination group and the second reference combination group do not overlap, thereby determining the rotation direction of the wheel end.

[0005] In a preferred embodiment: the signal processing unit pre-stores a desired cyclic sequence of adjacent circumferential spacing of the second via; in step S3, the signal processing unit establishes mode synchronization after continuously recording a preset number of time intervals matching the desired cyclic sequence; after mode synchronization is established, the signal processing unit compares each subsequent time interval with the corresponding desired interval in the desired cyclic sequence: When the actual time interval is less than the corresponding expected time interval and the ratio of the two is less than the first preset ratio, it is determined that there is an interference pulse in the time interval, the interference pulse is discarded, and the two time intervals before and after the interference pulse are merged and re-compared with the expected cyclic sequence. At the same time, the position is marked as an abnormal marker. When the actual time interval is greater than the corresponding expected time interval and the ratio of the two is greater than the second preset ratio, it is determined that there is a pulse loss. The signal processing unit infers the position of the second through hole corresponding to the lost pulse according to the expected cyclic sequence and outputs the through hole blockage fault signal, and marks the position as an abnormal marker. The time interval sequence after the above verification is used for direction determination in step S4; In step S4, when the direction discrimination result obtained by the signal processing unit is inconsistent with the previously output direction signal, the verification record of the most recent preset number of time intervals is checked back. If the abnormal mark exists in the verification record, the previously output direction signal is maintained without switching until there are no abnormal marks in the subsequent preset number of time intervals and the direction discrimination result is consistent, and then the output direction signal is updated.

[0006] In a preferred embodiment: the signal processing unit pre-stores the central angle between each adjacent second through hole; in step S2, the signal processing unit obtains the corresponding central angle according to the current interval position determined after mode synchronization, and calculates the wheel end reference speed from the central angle and the time interval between adjacent pulses; The signal processing unit predicts the expected arrival time window of the next pulse in the first pulse signal based on the wheel end reference speed: when the first pulse arrives within the expected arrival time window, the wheel end speed is updated based on the first pulse; when the first pulse arrives earlier than the expected arrival time window, the first pulse is determined to be an interference pulse and discarded; when the expected arrival time window ends and the first pulse has not yet arrived, it is determined that the first pulse signal has pulse loss, and the wheel end reference speed is used as the wheel end speed output and a fault signal is output. When the wheel-end speed is lower than the preset speed threshold, the signal processing unit updates the wheel-end speed according to the corresponding central angle and time interval for each second pulse received.

[0007] In a preferred embodiment: the radius of the first circumferential trajectory is greater than the radius of the second circumferential trajectory, and the diameter of the first through hole is greater than the diameter of the second through hole.

[0008] In a preferred embodiment: in step S3, the signal processing unit uses the pulse period of the first pulse signal as a reference clock to convert the time interval between adjacent pulses in the second pulse signal into a normalized ratio relative to the pulse period; in step S4, the signal processing unit constructs the ordered combination of two consecutive normalized ratios in chronological order and compares them.

[0009] In a preferred embodiment: the circumferential spacing between adjacent holes of the plurality of second through holes on the second circumferential trajectory includes a first spacing, a second spacing, and a third spacing of different sizes, wherein the first spacing is smaller than the second spacing, the second spacing is smaller than the third spacing, and the first spacing, the second spacing, and the third spacing are arranged cyclically on the second circumferential trajectory in the order of the first spacing, the second spacing, and the third spacing; in step S4, the signal processing unit compares the spacing type corresponding to two consecutive normalized ratio values ​​with a preset first reference combination group and a second reference combination group. The first reference combination group includes an ordered combination of the first spacing and the second spacing, an ordered combination of the second spacing and the third spacing, and an ordered combination of the third spacing and the first spacing. The second reference combination group includes an ordered combination of the third spacing and the second spacing, an ordered combination of the second spacing and the first spacing, and an ordered combination of the first spacing and the third spacing. When the ordered combination of the spacing corresponding to two consecutive normalized ratio values ​​belongs to the first reference combination group, it is determined that the wheel end rotates in the first direction; when it belongs to the second reference combination group, it is determined that the wheel end rotates in the second direction.

[0010] In a preferred embodiment: the wheel body includes a first wheel and a second wheel arranged in parallel and spaced apart. The first wheel and the second wheel are fixedly connected to the same rotating shaft and rotate synchronously with the wheel end. The signal processing unit receives a first wheel detection signal group from the first wheel and a second wheel detection signal group from the second wheel in parallel, calculates the wheel end speed and direction respectively, and compares them. When the two sets of calculation results are consistent, the result is output.

[0011] In a preferred embodiment: the signal processing unit performs a validity check on each wheel detection signal group. The validity check includes checking whether the detection pulse signal is missing, whether the pulse period is within a preset range, and whether the detection direction discrimination result jumps between adjacent measurement cycles when the wheel end speed is higher than a preset verification speed threshold. When one of the wheel detection signal groups fails the validity check or the two sets of calculation results are inconsistent, the wheel detection signal group is blocked and the calculation result of the other wheel detection signal group is used as the output. After the blocked wheel detection signal group is restored and the two sets of calculation results are consistent for a preset number of consecutive cycles, the dual-channel comparison output is restored.

[0012] In a preferred embodiment: In step S4, the signal processing unit continuously confirms the direction discrimination result: the corresponding direction signal is output only when the discrimination results are consistent for a preset number of consecutive times; when the discrimination result switches between the first direction and the second direction, the previous direction signal is maintained until the discrimination results are consistent for a preset number of consecutive times before switching the output.

[0013] A component for synchronously measuring wheel speed and rotation direction, used to implement the aforementioned synchronous measurement method for wheel speed and rotation direction, is characterized in that it includes a first wheel disk and a second wheel disk fixedly connected to the same rotating shaft and rotating synchronously with the wheel end, the first wheel disk and the second wheel disk being arranged parallel and spaced apart; Both the first and second circumferential disks are provided with a plurality of first through holes evenly distributed along a first circumferential trajectory and a plurality of second through holes distributed along a second circumferential trajectory. The first and second circumferential circumferential trajectories are concentric circles with unequal radii. The circumferential spacing between adjacent holes of the plurality of second through holes on the second circumferential trajectory includes a first spacing, a second spacing, and a third spacing of different sizes. The first spacing is smaller than the second spacing, the second spacing is smaller than the third spacing, and the first spacing, the second spacing, and the third spacing are arranged cyclically in the order of the first spacing, the second spacing, and the third spacing. The first wheel and the second wheel are each equipped with an independent first detection element and a second detection element. The detection end of the first detection element faces the first circumferential track and outputs a first pulse signal when passing through the first through hole. The detection end of the second detection element faces the second circumferential track and outputs a second pulse signal when passing through the second through hole. It also includes a signal processing unit, which comprises a timing module and a direction discrimination module. The timing module records the time interval between adjacent pulses in the second pulse signal. The signal processing unit normalizes the time interval of the second pulse signal using the pulse period of the first pulse signal as a reference clock. The direction discrimination module constructs an ordered combination of two consecutive normalized ratios in chronological order and compares it with a preset reference combination before outputting a direction signal. The signal processing unit simultaneously receives and compares two wheel detection signal groups from the first wheel and the second wheel. When one wheel detection signal group is abnormal, the calculation result of the other wheel detection signal group is used as the output.

[0014] Compared with existing technologies, this invention encodes directional information in the spatial arrangement of hole spacing by setting three different circumferential spacings in the inner ring and cyclically arranging them in a fixed order. The ordered combinations generated by forward and reverse rotation do not overlap, mathematically ensuring that a single sensor can directly determine the direction of rotation at the wheel end without needing to take signals from the motor end. This eliminates detection failures caused by the inconsistency between the motor end signal and the actual rotation of the wheel under conditions such as belt slippage and coupling disconnection. At the same time, compared with the orthogonal encoder scheme, it saves one phase difference signal channel, halving the number of wiring harnesses and interfaces. The inner ring encoding sequence carries directional information and also serves as a verification benchmark. Through mode synchronization, interference pulse discarding and merging, pulse loss location, and abnormal marking and interlocking with the direction output, the same hole system can simultaneously achieve direction determination and error correction. After error correction, the complete sequence can continue to be used for direction determination, and blockage faults can be accurately located to specific hole positions. The reference speed is calculated using the interval after inner ring verification, and the outer ring pulse arrival window is predicted, forming a dual verification with the outer ring normalized verification of the inner ring. The closed-loop verification system ensures that the two signals, while not serving as references for each other, provide mutual reliability guarantees. It distinguishes between interference and signal loss faults based on whether the pulse arrives early or late. The outer ring pulse period serves as a reference clock to normalize the intervals, making the criterion a dimensionless constant that depends only on geometric dimensions. This ensures uniform validity across the entire speed range without requiring segmented calibration for different speed intervals. The ratio of adjacent intervals for the three spacings is no less than 1.2, and the ratio of the maximum to the minimum spacing is less than 2. This guarantees sufficient differentiation steps between normalized ratios and compatibility with pulse loss criteria. The parallel connection of the two discs allows the other disc to continue operating independently even if one disc fails. Combined with validity checks, speed gating, direction jump detection, and continuous confirmation anti-jitter, it ensures stable output in industrial environments with dust, vibration, and electromagnetic interference. The component integrates the speed measuring hole system, the coded direction judging hole system, dual-disc redundancy, and signal processing into one unit. After installation, it directly outputs two digital signals—speed and direction—at the rotor. All functions are implemented in parallel and are independent of each other, allowing for degraded operation under single-point failure. Attached Figure Description

[0015] Figure 1This invention relates to a structural schematic diagram of a component for synchronously measuring wheel speed and rotation direction.

[0016] First wheel 1; second wheel 2; first through hole 3; second through hole 4; first detection element 5; second detection element 6; rotating shaft 7. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to the accompanying drawings.

[0018] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

[0019] This embodiment relates to a method and component for synchronously measuring wheel speed and rotation direction, applicable to the detection of speed and direction of rotation of belt conveyor pulleys. Figure 1 As shown, the wheel body rotates synchronously with the wheel end. Two rings of through holes are machined on the wheel body: the outer ring has multiple first through holes 3 evenly spaced along a first circumferential trajectory, and the inner ring has multiple second through holes 4 distributed along a second circumferential trajectory. The two circumferential trajectories are concentric circles with unequal radii. The circumferential spacing between adjacent holes 4 of the second through holes 4 is set to three different sizes. When the wheel rotates, each first through hole 3 passes through a first detection element 5 to generate a first pulse signal, and each second through hole 4 passes through a second detection element 6 to generate a second pulse signal.

[0020] The outer ring has three equally spaced first through holes 3, with adjacent holes having the same central angle. When the wheel rotates at a constant speed, the time interval between each hole passing the detection element is equal. The rotational speed can be calculated either by converting the pulse frequency to f=ω / (2π)×N1 (where N1 is the number of first through holes 3), or by measuring the time interval T between adjacent first pulses and converting it to ω=2π / (N1×T). The two methods are equivalent, and the uniformity of the pulse interval in this channel is guaranteed by machining. The inner ring has three different circumferential spacings for the second through holes 4. The central angles corresponding to the three spacings are d1, d2, and d3, arranged in ascending order, and cyclically in the order d1—d2—d3. The signal processing unit records the time interval between adjacent pulses in the second pulse signal and arranges them in chronological order to form a time interval sequence. During forward rotation, the time intervals pass sequentially through the sensors. The only ordered combinations of two consecutive intervals are (d1, d2), (d2, d3), and (d3, d1). During reverse rotation, the order is reversed, resulting in three ordered combinations: (d3, d2), (d2, d1), and (d1, d3). Comparing each pair of combinations, (d1, d2) and (d2, d1) have reversed element order; (d2, d3) and (d3, d2) have reversed element order; and (d3, d1) and (d1, d3) have reversed element order. No single element appears in both pairs simultaneously. The non-overlapping nature of the pairs is directly guaranteed by set theory and does not depend on sensor accuracy or signal amplitude. The signal processing unit identifies which pair the current ordered combination falls into to output the direction: if it falls into the forward rotation group, the wheel is determined to rotate in the first direction; if it falls into the reverse rotation group, the wheel is determined to rotate in the second direction. The initial direction determination is completed after the wheel has rotated through three inner holes. The reason for using three spacings instead of two is that when the two spacings α and β are arranged alternately, the forward sequence α—β—α—β and the reverse sequence β—α—β—α are cyclically shifted, and the interval ratio sequence seen by a single sensor is exactly the same, making it impossible to distinguish the direction. After introducing the third spacing, the ordered combination of any two consecutive spacings in the cyclic sequence no longer overlaps in either the forward or reverse direction, thus enabling direction determination. This scheme directly encodes the direction information in the spatial arrangement of the hole spacing. When applied to belt conveyors, it eliminates the need to obtain the direction signal from the drive motor end, saving cross-component wiring and signal synchronization calibration. It can still reflect the true direction of the wheel even under conditions where the motor end movement is inconsistent with the actual wheel movement, such as belt slippage or coupling disconnection. Compared with the quadrature encoder scheme, the inner ring direction determination only requires a single sensor, eliminating the need for two signal channels with a 90° phase difference, halving the number of wiring harnesses and interfaces. Furthermore, the mathematical structure of the three spacings eliminates the ambiguity of direction determination when the phase difference is close to 0° or 180° in the quadrature scheme in principle.

[0021] The signal processing unit pre-stores the desired cyclic sequence of adjacent circumferential spacing of the second via 4. The signal processing unit establishes mode synchronization after continuously recording two time intervals that match the desired cyclic sequence. Since the three spacing sizes are different, the ratio of any two consecutive intervals uniquely determines the current position in the d1-d2-d3 cyclic sequence. For example, detecting (d1, d2) indicates the next should be d3, and detecting (d2, d3) indicates the next should be d1. Two intervals are sufficient to lock the phase, eliminating the need to wait for a full lap.

[0022] After the mode synchronization is established, the signal processing unit compares each subsequent time interval with the corresponding expected interval in the expected cyclic sequence. When the actual time interval is less than the corresponding expected interval and the ratio of the two is less than 0.5, it is determined that there is an interference pulse in that time interval. The interference glitch generates an extra edge between two real holes, splitting the normal interval T into two segments, a and b, where a + b = T. The shorter of the two segments must not exceed 0.5T. The normal acceleration and deceleration of the belt conveyor causes the interval to change gradually. Under extreme conditions of an emergency stop angular acceleration of about 10 rad / s² (corresponding to a belt surface deceleration of about 2.5 m / s², and a pulley radius of r = 0.25 m), an angular velocity as low as 5 rad / s, and only 9 holes in the inner ring (angular distance of about 0.698 rad), the deviation of a single interval from the expected value is about αθ / (2ω²) ≈ 14%, which is far lower than the 50% abrupt change. Therefore, 0.5 is taken as the interference criterion threshold. If the glitch is located exactly at the midpoint of the interval, making both segments close to 0.5T, then the sum of the two segments is approximately equal to the desired interval, and the merged verification can still identify it. The signal processing unit discards the interference pulse, merges the two time intervals before and after it, and re-compares it with the desired cyclic sequence, while marking the position as an anomaly.

[0023] When the actual time interval is greater than the corresponding expected interval and the ratio of the two is greater than 1.5, a pulse loss is determined. When a pulse is lost, two adjacent intervals are merged into one long interval, and the measured value is approximately the sum of the two adjacent intervals. In the d1-d2-d3 cycle, the sum of adjacent intervals is d1+d2, d2+d3, d3+d1. When d3<2d1, the ratio of the sum of any two intervals to the smaller one is greater than 1.5—(d1+d2) / d1>2, (d2+d3) / d2>2, (d3+d1) / d3=1+d1 / d3>1.5 (because d1 / d3>0.5). However, under the above extreme conditions, the normal deceleration of the conveyor only increases the interval by about 14%, which is far below the 1.5 times threshold. The signal processing unit infers the position of the second through-hole 4 corresponding to the lost pulse based on the current position in the cycle sequence, outputs a through-hole blockage fault signal, and marks the position as an anomaly.

[0024] Only the time interval sequence after the above verification is used for direction determination. When the direction determination result is inconsistent with the previously output direction signal, the signal processing unit backtracks to check the verification records of the two most recent time intervals—a glitch pulse affects two intervals before and after it, and checking the two most recent intervals can cover its entire influence range. If there is an abnormal marker in the verification record, the previously output direction signal is maintained without switching until two or three consecutive intervals without abnormal markers and the direction determination results are consistent before updating the output. Two intervals provide a minimum protection window, and three intervals provide additional margin in strong interference environments such as contactor opening and closing and inverter radiation, which can be selected according to the EMC level of the industrial site. The inner ring code carries both direction information and verification information, and the same hole system realizes two functions without adding hardware; error correction adopts discarding and merging rather than simple filtering, and the sequence after error correction is complete and can still be used for direction determination; the blockage positioning is accurate to the specific hole position, while the equal-spacing hole scheme can only determine the presence or absence of a signal but cannot locate it; the abnormal marker and the direction output are interlocked, so that verification and direction determination are changed from serial steps to a mutually constrained state machine, and no erroneous flipping will occur within the error correction window.

[0025] Based on the above verification scheme, the signal processing unit also pre-stores the central angle between each adjacent second through hole 4. After the mode synchronization locks the position of the current interval in the loop sequence, the central angle θ_i corresponding to each interval is the design parameter of the wheel. After the signal processing unit looks up the table, it calculates the wheel end reference speed by ω_ref=θ_i / Δt_i. The outer ring equidistant hole angle distance θ0=2π / N1, the signal processing unit predicts the arrival time of the next outer ring pulse t_pred=t_n+θ0 / ω_ref with ω_ref, and sets an arrival window with a half width of Δ. Δ consists of two parts: the arrival time deviation Δt_acc=αθ0² / (2ω_ref³) caused by normal acceleration and deceleration and the measurement deviation of the reference speed itself Δt_ref=θ0Δω / ω_ref², that is, Δ=θ0 / ω_ref×(αθ0 / (2ω_ref²)+Δω / ω_ref). The normal start-stop angular acceleration of the belt conveyor is about 6 rad / s² (corresponding to a belt surface acceleration of about 1.5 m / s², r = 0.25 m). Taking N1 = 24 and the reference speed deviation Δω / ω_ref = 5% as the design margin, when ω_ref = 20 rad / s (belt speed about 5 m / s), T = 13.1 ms, Δt_acc ≈ 0.03 ms, Δt_ref ≈ 0.65 ms, and Δ / T about 5%; when ω_ref = 5 rad / s (belt speed about 1.25 m / s), T = 52.4 ms, Δt_acc ≈ 1.6 ms, Δt_ref ≈ 2.6 ms, and Δ / T about 8%. The window is adaptively widened with the speed. The quantization error of the outer ring single-interval speed measurement is ±1 / (2N1), which is less than ±2.1% when N1≥24. After mode verification, the deviation of the inner ring reference speed caused by sensor jitter and the machining tolerance of the center angle (IT10 grade stamping tolerance is about 0.1mm / 100mm=0.1%) is much less than the 5% design margin. The window is used as the boundary. The pulses arriving within the window are judged as real pulses. It is physically impossible for the pulse to arrive early - to arrive before the start of the window, it is necessary to complete an acceleration exceeding the normal start-stop capability within an interval. The pulses arriving late are judged as lost and are smoothly replaced by the wheel end reference speed, and a fault signal is output. When the deceleration of the emergency stop exceeds the normal range, the outer ring pulses are late in exceeding the window. At this time, it is necessary to treat it as lost - under the emergency stop condition, the inner ring reference speed continues to be updated, and the replacement output speed signal is uninterrupted, while triggering the fault mark. At low speeds, the outer ring pulse interval becomes longer. The threshold is determined by ω_th=2π / (N1×T_update), where T_update is 50ms (a typical requirement for the conveyor's electrical control system). When N1=24, ω_th≈5.2rad / s (belt speed approximately 1.3m / s). Below this value, the signal processing unit updates the rotational speed with θ_i / Δt_i when each inner ring pulse arrives. The inner ring pulses appear at different angular positions between the outer ring pulses, filling the update blind zone within the outer ring interval.The inner ring reference speed after verification is reversed by the outer ring pulse prediction window, forming a two-way verification closed loop with the aforementioned outer ring normalized verification inner ring. The two signals do not serve as references for each other but provide each other with reliability guarantees, and distinguish between two types of faults: interference and loss, based on early arrival and late arrival. The inherent defect of the outer ring equidistant sequence being unable to self-verify is compensated by the inner ring coded signal, and the reference speed replacement ensures that the speed output remains continuous even when the outer ring pulse is lost.

[0026] In the specific arrangement of the wheel hole system, the radius of the first circumferential trajectory is larger than the radius of the second circumferential trajectory, and the diameter of the first through hole 3 is larger than the diameter of the second through hole 4. The circumference of the outer ring, C1=2πR1, is larger than the circumference of the inner ring, C2=2πR2. With the same number of holes, the arc length between the outer ring holes is larger, allowing for the processing of larger hole diameters. When a large hole passes through the detection element, the change in the sensing area that is blocked or exposed is large: the change in detection distance of the inductive sensor and the change in the light transmission area of ​​the photoelectric sensor both increase with the hole diameter. Therefore, the outer ring speed measurement channel obtains a higher signal amplitude and a steeper pulse edge, reducing jitter at the trigger moment. The inner ring circumference is limited, and the three unequal spacings need to accommodate three arc lengths, d1, d2, and d3, within a smaller circumference. The small hole diameter saves circumferential space, ensuring that the three spacings have sufficient arc length differences within a limited angle. Taking R1 / R2=1.5 as an example, the outer ring circumference is 50% larger than the inner ring, and the outer ring aperture can be 1.5 to 2 times the inner ring aperture without inter-aperture interference. This arrangement optimizes both the signal quality of the speed measurement channel and the space utilization of the inner ring encoding. The large outer ring aperture serves the signal-to-noise ratio, while the small inner ring aperture serves the encoding density, each taking what it needs without encroaching on each other's space.

[0027] In the specific implementation of signal processing, the signal processing unit uses the pulse period of the first pulse signal as the reference clock, converts the time interval between adjacent pulses in the second pulse signal into a normalized ratio relative to that pulse period, and then compares two consecutive normalized ratios in an ordered combination according to their time sequence. Let the angular distance of the equidistant holes on the outer ring be θ0, the current pulse period of the outer ring be T0 = θ0 / ω, the time corresponding to the inner ring spacing d_i be Δt_i = d_i / ω, and the normalized ratio n_i = Δt_i / T0 = d_i / θ0. ω is eliminated in the numerator and denominator, making n_i a dimensionless constant that depends only on the wheel's geometry and is independent of the wheel's rotational speed. At high speeds, Δt_i and T0 decrease proportionally, while at low speeds, they increase proportionally, but n_i remains unchanged. The signal processing unit directly uses the relationship between the magnitudes of n_i to identify the spacing type and determine the direction. The criterion is consistent across the entire rotational speed range, eliminating the need to calibrate thresholds for different rotational speed intervals. If a fixed millisecond threshold is used instead of normalization, Δt_i may only be a few milliseconds at high speeds, and a threshold that is too large will lead to missed detections. At low speeds, Δt_i may be hundreds of milliseconds, and a threshold that is too small will lead to false detections. The outer ring pulse serves as both a speed measurement and direction determination reference, using a single signal channel for two purposes without increasing hardware overhead. Normalization also eliminates the speed fluctuations caused by the common mode of the inner and outer rings.

[0028] The ratios of the three spacings are determined under the following conditions. Let the ratios of adjacent spacings be k1 = d2 / d1 and k2 = d3 / d2. After normalization, the three ratios are d1 / θ0, k1d1 / θ0, and k1k2d1 / θ0, with the differences between adjacent ratios being (k1-1)d1 / θ0 and (k2-1)k1d1 / θ0. Industrial-grade sensors trigger jitter on the order of microseconds. At a rotor speed of 20 rad / s and 9 holes in the inner ring, the shortest interval is approximately 29 ms. The relative error caused by a 1 μs jitter is far less than 1%. After normalization, common-mode speed fluctuations are eliminated, and the residual non-common-mode error is also far less than 1%. We take k1 ≥ 1.2 and k2 ≥ 1.2, and the difference between adjacent ratios is not less than 20%, to provide sufficient margin to cover measurement errors and ensure that the three normalized ratios do not overlap. Meanwhile, this value must be compatible with the aforementioned 1.5 times loss criterion: d3 / d1=k1k2 must be less than 2. When k1=k2=1.2, d3 / d1=1.44<2, which meets the requirement. Taking k1=k2=1.2, that is, d2=1.2d1, d3=1.44d1, the three spacings are in an arithmetic progression relationship. During processing, only d1 is used as the reference to confirm the increment of d2 and d3. During detection, there is a 20% equal interval between the three normalized ratios. The forward-rotating ordered combination group {(d1,d2),(d2,d3),(d3,d1)} and the reverse-rotating group {(d3,d2),(d2,d1),(d1,d3)} do not intersect. After the signal processing unit identifies the spacing type corresponding to two consecutive normalized ratios, it can output the direction with one table lookup. The computational workload is only two comparisons and one table lookup, which has sufficient real-time margin compared to the millisecond-level pulse interval.

[0029] In terms of redundancy design, the wheel body includes a first wheel 1 and a second wheel 2 arranged in parallel intervals. Both are fixedly connected to the same rotating shaft 7 and rotate synchronously with the wheel ends. The signal processing unit receives the detection signal group from the first wheel 1 and the detection signal group from the second wheel 2 in parallel, calculates the wheel end speed and direction respectively, and compares them. Output is given when the two sets of results are consistent. The two wheels are rigidly connected to the same rotating shaft 7, with identical angular velocities and angular accelerations. The speed values ​​measured by the two independent channels at the same time should be equal and the direction values ​​should be the same within the quantization error range; this is the physical basis for comparison. The parallel dual-channel design ensures that the other channel can still operate independently even if one channel fails, significantly improving system reliability compared to a single-channel design. The axial spacing of the two wheels reduces the probability of external damage such as material dust accumulation, stone blockage, or mechanical impact affecting the same location on both wheels simultaneously to a much lower probability of damaging only one wheel. A single sensor open circuit or short circuit only affects one channel; the four pulse signals (outer ring + inner ring) of the other channel remain intact and usable. A dual-disc structure achieves triple redundancy at the sensor level, aperture system level, and channel level, eliminating the need for an external redundant controller to switch. A single channel failure does not cause the wheel end speed signal to be interrupted. For critical operating conditions such as underground conveying and port loading and unloading where speed signal interruption is not allowed, it can prevent a single point of failure from causing the entire conveyor line to shut down.

[0030] The signal processing unit performs a validity check on each wheel detection signal group. The check includes whether the pulse signal is missing, whether the pulse period is within the preset range, and whether the direction discrimination result jumps between adjacent measurement periods when the wheel end speed is higher than the preset verification speed threshold. The preset range of the pulse period is [0.5T, 2T], where T is the current expected period calculated based on the recent speed: the lower limit of 0.5T is consistent with the analysis of interference glitch splitting intervals, and the short intervals generated by glitch do not exceed 0.5T; the upper limit of 2T corresponds to the length of the merged intervals after a pulse is lost in the equidistant sequence, which is more conservative than the 1.5 times loss criterion of the inner circle, because the outer circle does not have the pattern verification assistance of the inner circle and requires a wider tolerance.

[0031] The rotational speed threshold for directional change detection is derived from physical constraints: the shortest time required for the wheel to decelerate from angular velocity ω to zero and then accelerate in the opposite direction to -ω is t_rev=2ω / α_max. The belt conveyor has a large moment of inertia, and α_max is taken as the maximum stopping angular acceleration a_max / r (a_max is about 2.5m / s², and when r=0.25m, α_max≈10rad / s²). If the pulse interval between adjacent outer rings T1=2π / (N1ω) is less than t_rev, then the wheel cannot complete the reverse direction within this interval, and the directional change must be abnormal. Let T1 = t_rev and solve for ω_th = sqrt(πa_max / (N1r)). When N1 = 12, ω_th ≈ 1.6 rad / s (belt speed approximately 0.4 m / s). When N1 = 48, ω_th ≈ 0.8 rad / s (belt speed approximately 0.2 m / s). Jump detection is only activated when the value is above this threshold. If the value is below this threshold, the conveyor may be in a jogging maintenance condition, and the actual reversal should not be misjudged.

[0032] When one of the wheel detection signal groups fails the validity check or the calculation results of the two groups are inconsistent, the signal processing unit blocks that wheel detection signal group and uses the calculation result of the other wheel detection signal group as the output. The dual-channel comparison output is restored after the blocked group recovers and the calculation results of the two groups are consistent for three consecutive cycles. Single-cycle consistency may be coincidental, but three consecutive cycles covering at least three outer-circle pulses and corresponding inner-circle pulses are sufficient to confirm stable recovery of the faulty channel. Intermittent faults will not cause frequent jumps in output between the two channels. The redundant system thus possesses a complete state machine for fault detection, safety degradation, and recovery confirmation. The speed threshold avoids the false blocking of low-speed real commutation. The [0.5T, 2T] threshold system is of the same origin as the inner-circle verification threshold system, and the fault judgment criteria for the inner and outer circles are unified.

[0033] Regarding the stability of the direction output, the signal processing unit continuously confirms the direction discrimination result: the corresponding direction signal is only output when the discrimination results are consistent for a preset number of consecutive times; when the discrimination result switches between the first and second directions, the output of the previous direction signal is maintained until the discrimination results are consistent for a preset number of consecutive times before switching. Electromagnetic interference in industrial environments, such as contactor opening and closing, inverter switching noise, and motor brush commutation, typically manifests as narrow pulse trains with a duration of less than one pulse cycle, affecting at most the discrimination result of one interval. When the number of consecutive confirmations is 2, the erroneous direction generated by a single interfered interval is rejected by the adjacent correct interval and is not propagated to the output; when it is 3, interference clusters lasting for two intervals can be suppressed. Taking N=2 as an example, the state machine maintains a direction counter. When the discrimination result is consistent with the current output, the counter is incremented by 1; when they are inconsistent, it is reset to zero and counts in the opposite direction starting from 0. The counter flips and outputs only when it reaches 2; an erroneous discrimination requires the next discrimination to also be erroneous for a false flip to occur. The probability that two consecutive intervals are simultaneously interfered with and have the same erroneous direction is the square of the single interval error probability, significantly reducing the probability of false flips. This mechanism trades a delay of 2 to 3 inner ring intervals (approximately 70 to 105 ms at 20 rad / s) for a significant improvement in the directional output anti-interference capability. This delay is negligible relative to the response time constant of the conveyor control system. It complements the aforementioned anomaly mark interlock: the anomaly mark interlock targets structured errors near the error correction location, while continuous confirmation targets unmarked random interference. Both cover different error modes.

[0034] The first detection element 5 and the second detection element 6 are inductive proximity switches or photoelectric sensors, fixedly mounted on the wheel end support, with a detection gap between the detection end and the surface of the wheel body. The inductive proximity switch's pre-amplifier LC oscillation circuit generates eddy current loss when a metal object is present in front of the detection end, and the oscillation amplitude decreases as the metal approaches: when the through-hole passes through, the detection end faces the air, the gap is equal to the installation gap g, and the oscillation amplitude is V_H; when the solid part passes through, the metal distance from the detection end is gt (t is the wheel thickness), the eddy current loss increases, and the oscillation amplitude drops to V_L. The comparator flips the output high and low levels with (V_H+V_L) / 2 as the threshold. The photocurrent at the receiving end of the photoelectric through-beam sensor is proportional to the light-transmitting area: when the through-hole passes through, the light path is open, outputting a high level; when the solid part passes through, the light path is blocked, outputting a low level. Both sensors operate non-contactly with no wearing parts. The detection gap g is 0.5 to 3 mm in the inductive scheme (determined by the rated detection distance Sn, typically operating within 0.8 Sn to ensure temperature stability), and 5 to 15 mm in the photoelectric scheme. When the circumferential width of the through-hole is equal to that of the solid part, a pulse train with a duty cycle of approximately 50% is generated. Subsequent circuitry directly processes the digital level, and the signal's anti-interference capability on the transmission line is superior to that of analog signals. The inductive type is dust-resistant, moisture-resistant, and vibration-resistant, making it suitable for the dusty and humid environment of belt conveyors. The photoelectric type has no requirements for the wheel material and has a high response frequency (up to 100kHz or higher), making it suitable for relatively clean high-speed operating conditions. The appropriate type can be selected based on the conveyor environment. Neither type changes the hole coding or signal processing logic.

[0035] This embodiment also relates to a component for synchronously measuring wheel speed and rotation direction, used to implement any of the above methods. The component includes a first wheel 1 and a second wheel 2 fixedly connected to the same rotating shaft 7 and rotating synchronously with the wheel end. The first wheel 1 and the second wheel 2 are arranged parallel to each other at intervals. Each wheel has multiple first through holes 3 evenly distributed along a first circumferential trajectory and multiple second through holes 4 distributed along a second circumferential trajectory. The two circumferential trajectories are concentric circles with unequal radii. The circumferential spacing between adjacent holes 4 includes a first spacing, a second spacing, and a third spacing of different sizes, with the first spacing smaller than the second spacing, the second spacing smaller than the third spacing, and the three spacings arranged cyclically in the order of first spacing, second spacing, and third spacing. Each wheel is equipped with an independent first detection element 5 and a second detection element 6. The detection end of the first detection element 5 faces the first circumferential trajectory and outputs a first pulse signal when passing through the first through hole 3. The detection end of the second detection element 6 faces the second circumferential trajectory and outputs a second pulse signal when passing through the second through hole 4.

[0036] The component also includes a signal processing unit, which comprises a timing module and a direction discrimination module. The timing module records the time intervals between adjacent pulses in the second pulse signal (using an internal high-speed clock with a resolution better than 1 μs), arranging them chronologically to form a time interval sequence. The signal processing unit normalizes the time intervals of the second pulse signal using the pulse period of the first pulse signal as a reference clock. The direction discrimination module constructs an ordered combination of two consecutive normalized ratios chronologically and compares it with a preset reference combination before outputting a direction signal. The signal processing unit simultaneously receives and compares two wheel detection signal groups from the first wheel 1 and the second wheel 2. If one wheel detection signal group is abnormal, the calculation result of the other wheel detection signal group is used as the output.

[0037] The distance between the two discs is guaranteed by the length of the hub bushing, and the end face runout is controlled within the allowable range of the sensor detection gap. Each disc has N1 equally spaced large holes on its outer ring and 3n small holes on its inner ring (n is the number of repetitions of the d1-d2-d3 cycle; n≥2 ensures at least two complete cycles within one revolution, improving mode synchronization speed). Each disc is equipped with two detection elements, one aligned with the outer ring and the other with the inner ring, for a total of four pulse signal inputs to the signal processing unit. This component integrates the speed measuring hole system, the three-value encoding direction determination hole system, dual-disc redundancy, and signal processing into one unit. After installation, it directly outputs two digital signals—speed and direction—at the wheel, without requiring motor-end signal input, and can still reflect the true state of the wheel even when the belt slips. The inner ring's three-value encoding uses a single sensor instead of an orthogonal dual-phase sensor, and the outer ring's normalization ensures the criterion does not change with speed. The parallel connection of the two discs allows the other to work independently even if one channel fails. Each function is implemented in parallel on the same component and is independent of the others: the orientation function does not depend on the dual-disc redundancy and can work with a single disk; the redundancy function does not depend on the coding type and the dual disks with equidistant holes are also redundant; the normalization does not depend on the dual disks and can be normalized with a single disk. Under any single point of failure, the component can operate at a degraded level and will not completely lose its speed or orientation detection capability due to local failure.

[0038] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Unless otherwise specified, an element defined by the phrase "comprising..." or "including..." does not exclude the presence of additional elements in the process, method, article, or terminal device that includes said element. Additionally, in this document, "greater than," "less than," "exceeding," etc., are understood to exclude the stated number; "above," "below," "within," etc., are understood to include the stated number.

[0039] The above description of the embodiments is provided to facilitate understanding and use of the present invention by those skilled in the art. It is obvious to those skilled in the art that various modifications can be easily made to the embodiments, and the general principles described herein can be applied to other embodiments without creative effort. Therefore, the present invention is not limited to the above embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. A method for synchronously measuring wheel speed and rotation direction, characterized in that: Includes the following steps: S1. A wheel body that rotates synchronously with the wheel end is adopted. The wheel body has a plurality of first through holes evenly distributed along a first circumferential trajectory and a plurality of second through holes distributed along a second circumferential trajectory. The first circumferential trajectory and the second circumferential trajectory are concentric circles with unequal radii. The circumferential spacing between adjacent holes of the plurality of second through holes on the second circumferential trajectory includes at least three different sizes. When the wheel body rotates with the wheel end, the first through holes sequentially pass through a first detection element to generate a first pulse signal, and the second through holes sequentially pass through a second detection element to generate a second pulse signal. S2. The signal processing unit calculates the wheel end speed based on the pulse frequency or pulse period of the first pulse signal; S3. The signal processing unit records the time interval between adjacent pulses in the second pulse signal to form a time interval sequence; S4. The signal processing unit takes two consecutive time intervals from the time interval sequence and forms an ordered combination according to the time sequence. After comparing the ordered combination with a preset reference combination, it outputs a direction signal: the ordered combination when the wheel end rotates along the first direction belongs to the first reference combination group, and the ordered combination when the wheel end rotates along the second direction belongs to the second reference combination group. The first reference combination group and the second reference combination group do not overlap, thereby determining the rotation direction of the wheel end.

2. The method for synchronously measuring wheel speed and rotation direction according to claim 1, characterized in that: The signal processing unit pre-stores a desired cyclic sequence of adjacent circumferential spacing of the second through-hole; in step S3, the signal processing unit establishes mode synchronization after continuously recording a preset number of time intervals that match the desired cyclic sequence; after mode synchronization is established, the signal processing unit compares each subsequent time interval with the corresponding desired interval in the desired cyclic sequence: When the actual time interval is less than the corresponding expected time interval and the ratio of the two is less than the first preset ratio, it is determined that there is an interference pulse in the time interval, the interference pulse is discarded, and the two time intervals before and after the interference pulse are merged and re-compared with the expected cyclic sequence. At the same time, the position is marked as an abnormal marker. When the actual time interval is greater than the corresponding expected time interval and the ratio of the two is greater than the second preset ratio, it is determined that there is a pulse loss. The signal processing unit infers the position of the second through hole corresponding to the lost pulse according to the expected cyclic sequence and outputs the through hole blockage fault signal, and marks the position as an abnormal marker. The time interval sequence after the above verification is used for direction determination in step S4; In step S4, when the direction discrimination result obtained by the signal processing unit is inconsistent with the previously output direction signal, the verification record of the most recent preset number of time intervals is checked back. If the abnormal mark exists in the verification record, the previously output direction signal is maintained without switching until there are no abnormal marks in the subsequent preset number of time intervals and the direction discrimination result is consistent, and then the output direction signal is updated.

3. The method for synchronously measuring wheel speed and rotation direction according to claim 2, characterized in that: The signal processing unit pre-stores the central angle between each adjacent second through hole; in step S2, the signal processing unit obtains the corresponding central angle according to the current interval position determined after mode synchronization, and calculates the wheel end reference speed from the central angle and the time interval between adjacent pulses; The signal processing unit predicts the expected arrival time window of the next pulse in the first pulse signal based on the wheel end reference speed: when the first pulse arrives within the expected arrival time window, the wheel end speed is updated based on the first pulse; when the first pulse arrives earlier than the expected arrival time window, the first pulse is determined to be an interference pulse and discarded; when the expected arrival time window ends and the first pulse has not yet arrived, it is determined that the first pulse signal has pulse loss, and the wheel end reference speed is used as the wheel end speed output and a fault signal is output. When the wheel-end speed is lower than the preset speed threshold, the signal processing unit updates the wheel-end speed according to the corresponding central angle and time interval for each second pulse received.

4. The method for synchronously measuring wheel speed and rotation direction according to claim 1, characterized in that: The radius of the first circular track is greater than the radius of the second circular track, and the diameter of the first through hole is greater than the diameter of the second through hole.

5. The method for synchronously measuring wheel speed and rotation direction according to claim 1, characterized in that: In step S3, the signal processing unit uses the pulse period of the first pulse signal as a reference clock to convert the time interval between adjacent pulses in the second pulse signal into a normalized ratio relative to the pulse period; in step S4, the signal processing unit constructs the ordered combination of two consecutive normalized ratios in chronological order and compares them.

6. The method for synchronously measuring wheel speed and rotation direction according to claim 5, characterized in that: The circumferential spacing between adjacent holes of the plurality of second through holes on the second circumferential trajectory includes a first spacing, a second spacing and a third spacing of different sizes, wherein the first spacing is smaller than the second spacing, the second spacing is smaller than the third spacing, and the first spacing, the second spacing and the third spacing are arranged cyclically on the second circumferential trajectory in the order of the first spacing, the second spacing and the third spacing. In step S4, the signal processing unit compares the spacing types corresponding to two consecutive normalized ratios with a preset first reference combination group and a second reference combination group. The first reference combination group includes an ordered combination of the first spacing and the second spacing, an ordered combination of the second spacing and the third spacing, and an ordered combination of the third spacing and the first spacing. The second reference combination group includes an ordered combination of the third spacing and the second spacing, an ordered combination of the second spacing and the first spacing, and an ordered combination of the first spacing and the third spacing. When the ordered combination of the spacings corresponding to two consecutive normalized ratios belongs to the first reference combination group, it is determined that the wheel end rotates in the first direction. When it belongs to the second reference combination group, it is determined that the wheel end rotates in the second direction.

7. The method for synchronously measuring wheel speed and rotation direction according to claim 1, characterized in that: The wheel body includes a first wheel and a second wheel arranged in parallel at intervals. The first wheel and the second wheel are fixedly connected to the same rotating shaft and rotate synchronously with the wheel end. The signal processing unit receives the first wheel detection signal group from the first wheel and the second wheel detection signal group from the second wheel in parallel, calculates the wheel end speed and direction respectively, and compares them. When the two sets of calculation results are consistent, the result is output.

8. The method for synchronously measuring wheel speed and rotation direction according to claim 7, characterized in that: The signal processing unit performs a validity check on each wheel detection signal group. The validity check includes checking whether the detection pulse signal is missing, whether the pulse period is within a preset range, and whether the detection direction discrimination result jumps between adjacent measurement cycles when the wheel end speed is higher than the preset verification speed threshold. When one of the roulette detection signal groups fails the validity check or the two sets of calculation results are inconsistent, the roulette detection signal group is blocked and the calculation result of the other roulette detection signal group is used as the output. The dual-channel comparison output is restored after the blocked roulette detection signal group is restored and the two sets of calculation results are consistent for a preset number of consecutive cycles.

9. The method for synchronously measuring wheel speed and rotation direction according to claim 1, characterized in that: In step S4, the signal processing unit continuously confirms the direction discrimination result: it only outputs the corresponding direction signal when the discrimination results are consistent for a preset number of consecutive times; when the discrimination result switches between the first direction and the second direction, it keeps outputting the previous direction signal until the discrimination results are consistent for a preset number of consecutive times before switching the output.

10. A component for synchronously measuring wheel speed and rotation direction, used to implement the method for synchronously measuring wheel speed and rotation direction according to any one of claims 1-9, characterized in that: It includes a first wheel and a second wheel that are fixedly connected to the same rotating shaft and rotate synchronously with the wheel end, with the first wheel and the second wheel arranged parallel and spaced apart; Both the first and second roulette wheels are provided with a plurality of first through holes evenly distributed along a first circumferential trajectory and a plurality of second through holes distributed along a second circumferential trajectory. The first circumferential trajectory and the second circumferential trajectory are concentric circles with unequal radii. The circumferential spacing between adjacent holes of the plurality of second through holes on the second circumferential trajectory includes a first spacing, a second spacing and a third spacing of different sizes, wherein the first spacing is smaller than the second spacing, the second spacing is smaller than the third spacing, and the first spacing, the second spacing and the third spacing are arranged cyclically in the order of the first spacing, the second spacing and the third spacing; The first wheel and the second wheel are each equipped with an independent first detection element and a second detection element. The detection end of the first detection element faces the first circumferential track and outputs a first pulse signal when passing through the first through hole. The detection end of the second detection element faces the second circumferential track and outputs a second pulse signal when passing through the second through hole. It also includes a signal processing unit, which comprises a timing module and a direction discrimination module. The timing module records the time interval between adjacent pulses in the second pulse signal. The signal processing unit normalizes the time interval of the second pulse signal using the pulse period of the first pulse signal as a reference clock. The direction discrimination module constructs an ordered combination of two consecutive normalized ratios in chronological order and compares it with a preset reference combination before outputting a direction signal. The signal processing unit simultaneously receives and compares two wheel detection signal groups from the first wheel and the second wheel. When one wheel detection signal group is abnormal, the calculation result of the other wheel detection signal group is used as the output.

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