WO2020006987A1

WO2020006987A1 - Eddy current detection-based adaptive steel ball sorting device

Info

Publication number: WO2020006987A1
Application number: PCT/CN2018/121084
Authority: WO
Inventors: 谢凤芹; 马龙玉; 张传伟; 杜如栋; 张华宇
Original assignee: 山东科技大学
Priority date: 2018-07-04
Filing date: 2018-12-14
Publication date: 2020-01-09
Also published as: CN108787414A

Abstract

An eddy current detection-based adaptive steel ball sorting device, comprising: a steel ball sorting unit, comprising two sorting rollers (6, 61) provided in parallel, the sorting rollers both being stepped sorting rollers; and an eddy current detection unit, comprising eddy current sensors (4), a colpitts oscillator, a detection circuit (28) and an MCU microprocessor which are electrically connected, two groups of the eddy current sensors being provided at both ends of the two sorting rollers in pairs, and the axes of the eddy current sensors and the axes of the two sorting rollers being in a same plane. Said sorting device has high sorting efficiency, reduces diameter error rate of steel balls, and thus is accurate.

Description

Technical field of steel ball adaptive sorting based on eddy current detection

[0001] The present invention relates to a steel ball sorting device, and in particular, to a steel ball adaptive sorting device based on eddy current detection, and belongs to the field of machinery.

Background technique

[0002] The polished steel balls need to be sorted according to size, and the various types of steel balls are classified to facilitate further testing. In the traditional process, the steel ball sorting needs to rely on the experience of the workers to adjust the distance of the sorting rollers. The workers need special training and are easily affected by subjective factors. The quality of the steel balls is difficult to guarantee and the standardization is low. The method of manually adjusting the spacing of the sorting rollers makes the accuracy of steel ball sorting low, and the equipment needs to be repeatedly debugged, the sorting efficiency is low, and the degree of equipment self-adaptation is low.

Summary of invention

technical problem

Problem solution

Technical solutions

[0003] The problem to be solved by the present invention is to address the above-mentioned shortcomings, and to provide a steel ball adaptive sorting device based on eddy current detection.

[0004] In order to solve the above problems, the technical solution adopted by the present invention is as follows: A steel ball adaptive sorting device based on eddy current detection is characterized in that it includes:

[0005] The steel ball sorting unit includes two sorting rollers arranged in parallel, and both sorting rollers are stepped.

[0006] Furthermore, universal bearings are respectively provided on both ends of the two sorting rollers, and the universal bearings are arranged on the sorting roller support seat.

[0007] Further, it further includes:

[0008] The driving unit includes timing belt pulleys respectively disposed at the left ends of the two sorting rollers, and is connected to the stepping motor driven by the sorting rollers through a timing belt.

[0009] Further, it further includes:

[0010] The fine adjustment unit for the clearance of the sorting roller includes a guide rail, a lead screw, and a guide rail respectively disposed at both ends of the two sorting rollers. There is a slider on the slider, and the sorting roller support seat is arranged on the slider.

[0011] Further, a screw nut is provided on the sorting roller support seat of the two sorting rollers, and the two screw nuts and the screw are driven by threads.

[0012] Further, the surface of the lead screw mated with the two lead screw nuts has threads of equal length and opposite rotation directions, and a fine-tuning stepping motor is connected to the coupling at the front end of the lead screw.

[0013] Further, it further includes:

[0014] an eddy current detection unit including an electrically connected eddy current sensor, a capacitive three-point oscillator, a detection circuit, and an MCU microprocessor;

[0015] The eddy current sensor is provided in two groups, arranged in pairs at both ends of two sorting rollers, and the axis of the eddy current sensor and the axis of the two sorting rollers are on the same plane.

[0016] Further, the detection circuit includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, a capacitor C6, a transistor BG1, a transistor BG2 And inductor L1, where BG1, Cl, C2, and C3 form a capacitor three-point oscillator.

[0017] Further, it further includes:

[0018] The steel ball collecting unit includes a receiving hopper and a receiving drawer arranged on a support plate, a feeding opening of the receiving hopper is arranged at the bottom of two sorting rollers, and a receiving drawer is arranged at a lower part of the discharging opening of the receiving hopper.

The beneficial effects of the invention

Beneficial effect

[0019] The present invention adopts the above technical solutions, and has the following advantages compared with the prior art:

[0020] 1. The distance from the sorting roller is directly measured by 4 eddy current sensors, the stepper motor is finely adjusted by the front roller pitch, and the stepper motor is finely adjusted by the stepper motor. The pitch of the sorting roller is finely adjusted by indirect measurement. The distance between the two sorting rollers is required. The distance at this time is the outer diameter of the steel ball to be sorted. Compared with traditional manual sorting and manual adjustment equipment, it has high sorting efficiency and low sorting cost. The advantages.

[0021] 2. In the sorting device, the front roller pitch fine-tuning stepper motor, the rear roller pitch fine-tuning stepper motor and 4 eddy current sensors constitute a closed-loop monitoring system to achieve adaptive sorting of steel balls, and the overall structure is simple. It is reliable, reduces the labor intensity of workers, and improves the detection accuracy of the sorting device.

[0022] 3. By adopting the technical solution of the present invention, the spherical error of the steel ball is 0.08pm, the efficiency can reach 15000 grains per hour, the sorting efficiency is higher, and the diameter error rate of the steel ball is more accurate. Brief description of the drawings

BRIEF DESCRIPTION OF THE DRAWINGS

1 is a schematic structural diagram of a steel ball adaptive sorting device according to an embodiment of the present invention;

[0024] FIG. 2 is a schematic structural diagram of a fine adjustment unit for a gap between a sorting roller in an embodiment of the present invention;

[0025] FIG. 3 is a left side view of FIG. 1;

[0026] FIG. 4 is a schematic diagram of a closed-loop adjustment system of an eddy current detection unit in an embodiment of the present invention;

5 is a schematic diagram of an eddy current detection unit according to the present invention;

6 is a structure of a fuzzy PID controller in an embodiment of the present invention;

7 is a stepped structure of a sorting roller in an embodiment of the present invention;

[0030] wherein

[0031] 1-Front roller pitch fine-tuning stepper motor, 2-Coupling, 3-Timing belt, 4-Eddy current sensor, 5-Timing belt wheel

, 6-left sorting roller, 7-universal bearing, 8-take-up drawer, 9-hopper, 10-eddy current sensor support frame, 11-support plate, 12-bearing, 13-bearing seat, 14-wire Bar, 15-lead screw nut, 16-sorting roller support, 17-shaft sleeve, ₁₈ -screw, ₁₉ -guide rail, 20-slider, 22-left sorting roller drive stepper motor, 24-right sorting Roller driven stepper motor, 25-fine stepper motor for rear roller pitch, 28-detection circuit, 61-right sorting roller.

Invention Examples

Embodiments of the invention

[0032] Embodiment 1 provides a steel ball adaptive sorting device based on eddy current detection, which has a high degree of self-adaptation, accurate sorting, and high sorting efficiency.

[0033] The technical solution of the present invention is described in detail below with reference to the accompanying drawings, so as to make it easier to understand and master.

[0034] As shown in FIGS. 1 to 7, a steel ball adaptive sorting device based on eddy current detection includes a steel ball sorting unit, a sorting roller gap fine-tuning unit, a driving unit, an eddy current detecting unit, and steel. Ball collection unit

[0035] Steel ball sorting unit:

[0036] The left sorting roller 6 and the right sorting roller 61 are arranged in parallel, the left and right sorting rollers 6 and 61 are stepped, and the two ends of the left and right sorting rollers 61 and 61 are respectively A universal bearing 7 is provided, and the universal bearing 7 is provided on the sorting roller support base 16, and the left ends of the left and right sorting rollers 6 and 61 are respectively drivingly connected to the driving unit.

[0037] The driving unit:

[0038] It includes a timing belt pulley 5 provided at the left ends of the left and right sorting rollers 6 and 61, respectively. The timing belt pulley 5 at the end is drivingly connected with the left sorting roller driving stepper motor 22 through the timing belt 3, and the right sorting roller 61 1 The timing belt pulley 5 at the left end is driven by another timing belt 3 and the right sorting roller. Into the motor 24 drive connection.

[0039] The universal roller bearing is used to adjust the angle of the sorting roller to ensure that the gap between the ends of the sorting roller and the fine-tuning unit of the sorting roller are matched, and the rotation speed of the two sorting rollers is ensured to be the same through the timing belt drive.

[0040] Sorting roller gap fine adjustment unit:

[0041] The guide rail 19 and the lead screw 14 are respectively provided on both ends of the left and right sorting rollers 6 and 61, and the guide rail 19 is provided on the support plate 11. The guide rail 19 has a slider 20 and a sorting roller support. The seat 16 is arranged on the slider 20, and the sorting roller support seat 16 of the left sorting roller 6 and the right sorting roller 61 is provided with a screw nut 15 respectively. The two screw nuts 15 and the screw 14 are driven by threads. The surface of the lead screw 14 matched with the two lead screw nuts 15 has threads of opposite lengths with opposite rotation directions. The two ends of the lead screw 14 are fixed on the support plate 11 through a bearing seat 13 and screws 18, and a coupling is provided on the bearing seat 13. 2. Bearing 12, shaft sleeve 17, front-end coupling 2 is connected to the front roller pitch fine-tuning stepper motor 1, and rear-end coupling 2 is connected to the rear roller pitch fine-tuning stepper motor 25.

[0042] In order to improve the smoothness of the operation of the ball screw in the fine adjustment unit of the gap between the sorting rollers, the screw 14 is provided with a bearing 12, a sleeve 17 and a bearing seat 13.

[0043] Eddy current detection unit:

[0044] The eddy current sensor 4, an electric capacitance three-point oscillator, a detection circuit 28 and an MCU microprocessor are included. The eddy current sensor 4 is mounted on a support plate 11 through an eddy current sensor support frame 10. The eddy current sensor 4 is provided with The two groups have the same performance and are arranged in pairs at both ends of the two sorting rollers, and the axis of the eddy current sensor 4 and the axis of the two sorting rollers are on the same plane;

[0045] The detection circuit 28 includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, a capacitor C6, a transistor BG1, a transistor BG2, and Inductor L1, where BG1, Cl, C2, and C3 form a capacitive three-point oscillator, which generates a sinusoidal carrier signal with a frequency of f. During the measurement, if the change in the position of the cable causes a few microfabric changes in the distributed capacitance, the frequency of the oscillation circuit will change by several kilohertz, which will seriously affect the measurement result. For this reason, the shunt capacitor and the coil of the eddy current sensor are often assembled together, so that the distributed capacitance of the cable in parallel to the large capacitors C2 and C3 can greatly reduce the effect of the distributed capacitance on the frequency of the oscillator.

[0046] The values of BG1, Cl, C2, and C3 directly determine the starting condition of the oscillation circuit and the frequency value of the oscillation circuit, and the frequency value directly affects the linearity and sensitivity of the entire circuit. The value of C2 / C3 can neither It is too large and not too small, and needs to be determined through debugging. The most influential factor in the circuit is the probe coil of the sensor that appears as an inductor in the circuit. If C2 and C3 are both lpF, when the probe coil changes about 0.04 OmH and O.OOlmH, the frequency value of the circuit will change by more than ten KHz, so when winding the coil and selecting the coil, in order to ensure the consistency of the eddy current sensors of the front and rear rollers and improve the linearity and sensitivity of the detection result, a probe coil with the same parameters should be selected as much as possible.

[0047] The debugging work of the variable frequency and amplitude modulation eddy current sensor is also focused on improving the linearity and sensitivity of the sensor. In the voltage adjustment circuit, the ratio of R1 and R2 directly affects the peak-to-peak value of the oscillating output voltage. If the ratio is too large or too small, it will seriously affect the sensitivity of the sensor. This requires experimental debugging, which can not make the output voltage too high. High, saturation phenomenon occurs, and the output voltage cannot be too low, which affects the voltage gradient.

[0048] For a two-way displacement detection circuit, the final differential output voltage is 4 to 9V in a linear range of 0.45 to 0.95mm, and the linear midpoint value is 6.5V. Therefore, the sensitivity of the radial circuit after differential is reached 10V / mm. Adjust R1, R2, R3, and R4 to make the output voltage in the linear range reach 4 ~ 9V. At this time, the output sensitivity of each channel reaches 5V / mm.

[0049] The eddy current sensor 4 and a capacitive three-point oscillator are connected in series at the input of the detection circuit 28, and the eddy current sensor 4 is used as an inductor. When the parameters measured by the eddy current sensor 4 (the eddy current sensor 4 and the measuring roller 6 are measured) When the pitch is changed, it causes the inductance or impedance of the sensor coil to change, thereby changing the frequency of the oscillator. The frequency value is used to express the parameter change. The frequency is output to A / D for analog-to-digital conversion, and the digital signal is processed by the MCU. After being processed, it is displayed on the LCD display.

[0050] Steel ball collection unit:

[0051] The receiving hopper 9 and the receiving drawer 8 are provided on the support plate 11. The feeding opening of the receiving hopper 9 is provided at the bottom of the two sorting rollers. .

[0052] It provides convenience for subsequent detection of steel balls. During the detection process, the driving unit drives the two sorting rollers of the steel ball sorting unit to rotate (the direction is shown in FIG. 3), and the fine-tuning unit of the sorting roller fine movements The roller support base 16 of the steel ball sorting unit is adjusted, and the eddy current detection unit is in a detection state.

[0053] When the device starts to work, the power is first turned on, the eddy current sensor 4 works, and the displacement LI, L2 between the two sorting rollers 6 at this moment is displayed on the PC host software interface, according to the steel balls to be inspected in this batch. Diameter, the upper computer calculates the optimal distance LI ', L2' between the front and rear ends of the two sorting rollers. If L1 '= L1 and L2' = L2, then the left, The stepping motor driven by the right sorting roller rotates according to the set speed of the sorting roller, and the direction is as shown in FIG. 3, and then the steel ball gently falls on the two sorting rollers in order, close to the side of the synchronous pulley 5, The gap between the sorting rollers is a small distance L1 ', and the gap between the two sorting rollers at the other end is a large distance L2'. The steel balls that meet the requirements of this batch fall into the collection drawer 8 in the middle of the sorting rollers. Sorting is completed. If L1YL1 and L2YL2, it can be divided into four cases. If L1 '> L1 and L2'> L2, the fuzzy PID controller structure in Fig. 7 is adopted to realize the right rotation of the stepper motor. To achieve the purpose of L1 '= L1 and L2' = L2; if Ll '<L1 and L2'<L2, use the fuzzy PID controller structure in Figure 7 to achieve fine adjustment of the front and back distance of the stepper motor to turn left to reach L1 ' = L1 and L2 '= L2 purpose; if Ll'> L1 and L2 '<L2, use the fuzzy PID controller structure in Figure 7 to achieve right-turn fine-tuning stepper motors, and left-turn fine-tuning stepper motors to turn left To reach Ll '=

The purpose of L1 and L2 '= L2; if Ll' <L1 and L2 '> L2, the fuzzy PID controller structure in Fig. 7 is adopted to realize the left-turn fine-tuning stepper motor and the rear distance fine-tuning stepper motor. Reach Ll '=

The purpose of L1 and L2 '= L2. Repeat the above sorting process.

[0054] The invention is particularly suitable for distance measurement with an eddy current sensor, and the sorting efficiency is higher and more accurate.

[0055] The spherical error of some steel ball sorting devices is 0.13pm, and the maximum efficiency is 8000 grains per hour. According to the present invention, the spherical error of the steel balls is 0.08pm, and the efficiency can reach 15000 grains per hour. Instead of the traditional manual sorting, the sorting efficiency is higher and the diameter error rate of the steel ball is more accurate.

[0056] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that It can still modify the technical solutions described in the foregoing embodiments. For example, the fuzzy PID controller can also adopt other methods, as long as the functions described in the present invention can be realized, or some of the technical features are equivalently replaced. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

Claim

[Claim 1] A steel ball adaptive sorting device based on eddy current detection, comprising: a steel ball sorting unit, comprising two sorting rollers arranged in parallel, and both sorting rollers are stepped Type

[Claim 2] The steel ball adaptive sorting device according to claim 1, wherein two ends of the two sorting rollers are respectively provided with a universal bearing (7), and the universal bearing (7) is provided at Sorting roller support (16).

[Claim 3] The steel ball adaptive sorting device according to claim 1, further comprising: a driving unit including a timing belt pulley (5) provided at the left ends of the two sorting rollers, respectively, Driven by a stepper motor driven by a timing belt (3).

[Claim 4] The steel ball adaptive sorting device according to claim 1, further comprising: a sorting roller gap fine adjustment unit, including guide rails (19 ), The screw (14), the guide rail (19) has a slider (20), the sorting roller support (16) is arranged on the slider (20).

[Claim 5] The steel ball adaptive sorting device according to claim 4, characterized in that the sorting roller support (16) of the two sorting rollers are respectively provided with a screw nut (15), and The lead screw nut (15) and the lead screw (14) are driven by threads.

[Claim 6] The steel ball adaptive sorting device according to claim 5, characterized in that the surface of the screw (14) matched with the two screw nuts (15) has threads of equal length and opposite rotation directions, A fine-tuning stepping motor is connected to the coupling (2) at the front end of the lead screw (14).

[Claim 7] The steel ball adaptive sorting device according to claim 1, further comprising: an eddy current detection unit, including an electrically connected eddy current sensor (4), a capacitive three-point oscillator, and a detection circuit (28) and MCU microprocessor;

The eddy current sensor (4) is provided in two groups, arranged in pairs at both ends of two sorting rollers, and the axis of the eddy current sensor (4) and the axis of the two sorting rollers are on the same plane.

[Claim 8] The steel ball adaptive sorting device according to claim 7, characterized in that the detection circuit (2

8) Including resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, power Capacitor Cl, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, transistor BG1, transistor BG2, and inductor Ll, among which BG1, Cl, C2, and C3 constitute a capacitor three-point oscillator.

[Claim 9] The steel ball adaptive sorting device according to claim 1, further comprising: a steel ball collection unit, comprising a receiving hopper (9) and a receiving material provided on the support plate (11). The drawer (8), the feeding opening of the receiving hopper (9) is set at the bottom of the two sorting rollers, and the receiving drawer (8) is set at the lower part of the discharging opening of the receiving hopper (9).